Merge changes I9731d978,I9e325782,I441a4d4d,I86a85e48,I9268fd66, ... am: aeb15e8592 am: 788f03de26

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1471565

Change-Id: I495aa0430b4ddd2137a8b07af7dbe56ffe9a49d3

api/current.txt

@@ -42742,6 +42742,12 @@ package android.security.identity {
 
 package android.security.keystore {
 
+  public class BackendBusyException extends java.security.ProviderException {
+    ctor public BackendBusyException();
+    ctor public BackendBusyException(@NonNull String);
+    ctor public BackendBusyException(@NonNull String, @NonNull Throwable);
+  }
+
   public class KeyExpiredException extends java.security.InvalidKeyException {
     ctor public KeyExpiredException();
     ctor public KeyExpiredException(String);

core/api/current.txt

@@ -40910,6 +40910,12 @@ package android.security.identity {
 
 package android.security.keystore {
 
+  public class BackendBusyException extends java.security.ProviderException {
+    ctor public BackendBusyException();
+    ctor public BackendBusyException(@NonNull String);
+    ctor public BackendBusyException(@NonNull String, @NonNull Throwable);
+  }
+
   public class KeyExpiredException extends java.security.InvalidKeyException {
     ctor public KeyExpiredException();
     ctor public KeyExpiredException(String);

core/java/com/android/internal/os/ZygoteInit.java

@@ -73,6 +73,7 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.security.Provider;
 import java.security.Security;
+import java.util.Optional;
 
 /**
  * Startup class for the zygote process.
@@ -225,7 +226,17 @@ public class ZygoteInit {
         // AndroidKeyStoreProvider.install() manipulates the list of JCA providers to insert
         // preferred providers. Note this is not done via security.properties as the JCA providers
         // are not on the classpath in the case of, for example, raw dalvikvm runtimes.
-        AndroidKeyStoreProvider.install();
+        // TODO b/171305684 This code is used to conditionally enable the installation of the
+        //      Keystore 2.0 provider to enable teams adjusting to Keystore 2.0 at their own
+        //      pace. This code will be removed when all calling code was adjusted to
+        //      Keystore 2.0.
+        Optional<Boolean> keystore2_enabled =
+                android.sysprop.Keystore2Properties.keystore2_enabled();
+        if (keystore2_enabled.isPresent() && keystore2_enabled.get()) {
+            android.security.keystore2.AndroidKeyStoreProvider.install();
+        } else {
+            AndroidKeyStoreProvider.install();
+        }
         Log.i(TAG, "Installed AndroidKeyStoreProvider in "
                 + (SystemClock.uptimeMillis() - startTime) + "ms.");
         Trace.traceEnd(Trace.TRACE_TAG_DALVIK);

keystore/java/android/security/CheckedRemoteRequest.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security;
+
+import android.os.RemoteException;
+
+/**
+ * This is a Producer of {@code R} that is expected to throw a {@link RemoteException}.
+ *
+ * It is used by Keystore2 service wrappers to handle and convert {@link RemoteException}
+ * and {@link android.os.ServiceSpecificException} into {@link KeyStoreException}.
+ *
+ * @hide
+ * @param <R>
+ */
+@FunctionalInterface
+interface CheckedRemoteRequest<R> {
+    R execute() throws RemoteException;
+}

keystore/java/android/security/KeyStore2.java

@@ -0,0 +1,277 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security;
+
+import android.annotation.NonNull;
+import android.compat.annotation.ChangeId;
+import android.compat.annotation.EnabledAfter;
+import android.os.Build;
+import android.os.RemoteException;
+import android.os.ServiceManager;
+import android.os.ServiceSpecificException;
+import android.system.keystore2.IKeystoreService;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyEntryResponse;
+import android.system.keystore2.ResponseCode;
+import android.util.Log;
+
+import java.util.Calendar;
+
+/**
+ * @hide This should not be made public in its present form because it
+ * assumes that private and secret key bytes are available and would
+ * preclude the use of hardware crypto.
+ */
+public class KeyStore2 {
+    private static final String TAG = "KeyStore";
+
+    private static final int RECOVERY_GRACE_PERIOD_MS = 50;
+
+    /**
+     * Keystore operation creation may fail
+     *
+     * Keystore used to work under the assumption that the creation of cryptographic operations
+     * always succeeds. However, the KeyMint backend has only a limited number of operation slots.
+     * In order to keep up the appearance of "infinite" operation slots, the Keystore daemon
+     * would prune least recently used operations if there is no available operation slot.
+     * As a result, good operations could be terminated prematurely.
+     *
+     * This opens AndroidKeystore up to denial-of-service and unintended livelock situations.
+     * E.g.: if multiple apps wake up at the same time, e.g., due to power management optimizations,
+     * and attempt to perform crypto operations, they start terminating each others operations
+     * without making any progress.
+     *
+     * To break out of livelocks and to discourage DoS attempts we have changed the pruning
+     * strategy such that it prefers clients that use few operation slots and only briefly.
+     * As a result we can, almost, guarantee that single operations that don't linger inactive
+     * for more than 5 seconds will conclude unhampered by the pruning strategy. "Almost",
+     * because there are operations related to file system encryption that can prune even
+     * these operations, but those are extremely rare.
+     *
+     * As a side effect of this new pruning strategy operation creation can now fail if the
+     * client has a lower pruning power than all of the existing operations.
+     *
+     * Pruning strategy
+     *
+     * To find a suitable candidate we compute the malus for the caller and each existing
+     * operation. The malus is the inverse of the pruning power (caller) or pruning
+     * resistance (existing operation). For the caller to be able to prune an operation it must
+     * find an operation with a malus higher than its own.
+     *
+     * For more detail on the pruning strategy consult the implementation at
+     * https://android.googlesource.com/platform/system/security/+/refs/heads/master/keystore2/src/operation.rs
+     *
+     * For older SDK version, KeyStore2 will poll the Keystore daemon for a free operation
+     * slot. So to applications, targeting earlier SDK versions, it will still look like cipher and
+     * signature object initialization always succeeds, however, it may take longer to get an
+     * operation.
+     *
+     * All SDK version benefit from fairer operation slot scheduling and a better chance to
+     * successfully conclude an operation.
+     */
+    @ChangeId
+    @EnabledAfter(targetSdkVersion = Build.VERSION_CODES.R)
+    static final long KEYSTORE_OPERATION_CREATION_MAY_FAIL = 169897160L;
+
+    // Never use mBinder directly, use KeyStore2.getService() instead or better yet
+    // handleRemoteExceptionWithRetry which retries connecting to Keystore once in case
+    // of a remote exception.
+    private IKeystoreService mBinder;
+
+
+    @FunctionalInterface
+    interface CheckedRemoteRequest<R> {
+        R execute(IKeystoreService service) throws RemoteException;
+    }
+
+    private <R> R handleRemoteExceptionWithRetry(@NonNull CheckedRemoteRequest<R> request)
+            throws KeyStoreException {
+        IKeystoreService service = getService(false /* retryLookup */);
+        boolean firstTry = true;
+        while (true) {
+            try {
+                return request.execute(service);
+            } catch (ServiceSpecificException e) {
+                Log.e(TAG, "KeyStore exception", e);
+                throw new KeyStoreException(e.errorCode, "");
+            } catch (RemoteException e) {
+                if (firstTry) {
+                    Log.w(TAG, "Looks like we may have lost connection to the Keystore "
+                            + "daemon.");
+                    Log.w(TAG, "Retrying after giving Keystore "
+                            + RECOVERY_GRACE_PERIOD_MS + "ms to recover.");
+                    interruptedPreservingSleep(RECOVERY_GRACE_PERIOD_MS);
+                    service = getService(true /* retry Lookup */);
+                    firstTry = false;
+                } else {
+                    Log.e(TAG, "Cannot connect to Keystore daemon.", e);
+                    throw new KeyStoreException(ResponseCode.SYSTEM_ERROR, "");
+                }
+            }
+        }
+    }
+
+
+    private KeyStore2() {
+        mBinder = null;
+    }
+
+    public static KeyStore2 getInstance() {
+        return new KeyStore2();
+    }
+
+    private synchronized IKeystoreService getService(boolean retryLookup) {
+        if (mBinder == null || retryLookup) {
+            mBinder = IKeystoreService.Stub.asInterface(ServiceManager
+                    .getService("android.system.keystore2"));
+        }
+        return mBinder;
+    }
+
+    void delete(KeyDescriptor descriptor) throws KeyStoreException {
+        handleRemoteExceptionWithRetry((service) -> {
+            service.deleteKey(descriptor);
+            return 0;
+        });
+    }
+
+    /**
+     * List all entries in the keystore for in the given namespace.
+     */
+    public KeyDescriptor[] list(int domain, long namespace) throws KeyStoreException {
+        return handleRemoteExceptionWithRetry((service) -> service.listEntries(domain, namespace));
+    }
+
+    /**
+     * Create a grant that allows the grantee identified by {@code granteeUid} to use
+     * the key specified by {@code descriptor} withint the restrictions given by
+     * {@code accessVectore}.
+     * @see IKeystoreService#grant(KeyDescriptor, int, int) for more details.
+     * @param descriptor
+     * @param granteeUid
+     * @param accessVector
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyDescriptor grant(KeyDescriptor descriptor, int granteeUid, int accessVector)
+            throws  KeyStoreException {
+        return handleRemoteExceptionWithRetry(
+                (service) -> service.grant(descriptor, granteeUid, accessVector)
+        );
+    }
+
+    /**
+     * Destroys a grant.
+     * @see IKeystoreService#ungrant(KeyDescriptor, int) for more details.
+     * @param descriptor
+     * @param granteeUid
+     * @throws KeyStoreException
+     * @hide
+     */
+    public void ungrant(KeyDescriptor descriptor, int granteeUid)
+            throws KeyStoreException {
+        handleRemoteExceptionWithRetry((service) -> {
+            service.ungrant(descriptor, granteeUid);
+            return 0;
+        });
+    }
+
+    /**
+     * Retrieves a key entry from the keystore backend.
+     * @see IKeystoreService#getKeyEntry(KeyDescriptor) for more details.
+     * @param descriptor
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyEntryResponse getKeyEntry(@NonNull KeyDescriptor descriptor)
+            throws KeyStoreException {
+        return handleRemoteExceptionWithRetry((service) -> service.getKeyEntry(descriptor));
+    }
+
+    /**
+     * Get the security level specific keystore interface from the keystore daemon.
+     * @see IKeystoreService#getSecurityLevel(int) for more details.
+     * @param securityLevel
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyStoreSecurityLevel getSecurityLevel(int securityLevel)
+            throws KeyStoreException {
+        return handleRemoteExceptionWithRetry((service) ->
+            new KeyStoreSecurityLevel(
+                    service.getSecurityLevel(securityLevel)
+            )
+        );
+    }
+
+    /**
+     * Update the subcomponents of a key entry designated by the key descriptor.
+     * @see IKeystoreService#updateSubcomponent(KeyDescriptor, byte[], byte[]) for more details.
+     * @param key
+     * @param publicCert
+     * @param publicCertChain
+     * @throws KeyStoreException
+     * @hide
+     */
+    public void updateSubcomponents(@NonNull KeyDescriptor key, byte[] publicCert,
+            byte[] publicCertChain) throws KeyStoreException {
+        handleRemoteExceptionWithRetry((service) -> {
+            service.updateSubcomponent(key, publicCert, publicCertChain);
+            return 0;
+        });
+    }
+
+    /**
+     * Delete the key designed by the key descriptor.
+     * @see IKeystoreService#deleteKey(KeyDescriptor) for more details.
+     * @param descriptor
+     * @throws KeyStoreException
+     * @hide
+     */
+    public void deleteKey(@NonNull KeyDescriptor descriptor)
+            throws KeyStoreException {
+        handleRemoteExceptionWithRetry((service) -> {
+            service.deleteKey(descriptor);
+            return 0;
+        });
+    }
+
+    protected static void interruptedPreservingSleep(long millis) {
+        boolean wasInterrupted = false;
+        Calendar calendar = Calendar.getInstance();
+        long target = calendar.getTimeInMillis() + millis;
+        while (true) {
+            try {
+                Thread.sleep(target - calendar.getTimeInMillis());
+                break;
+            } catch (InterruptedException e) {
+                wasInterrupted = true;
+            } catch (IllegalArgumentException e) {
+                // This means that the argument to sleep was negative.
+                // So we are done sleeping.
+                break;
+            }
+        }
+        if (wasInterrupted) {
+            Thread.currentThread().interrupt();
+        }
+    }
+
+}

keystore/java/android/security/KeyStoreOperation.java

@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security;
+
+import android.annotation.NonNull;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.security.keymaster.KeymasterDefs;
+import android.system.keystore2.IKeystoreOperation;
+import android.system.keystore2.KeyParameter;
+import android.system.keystore2.ResponseCode;
+import android.util.Log;
+
+/**
+ * @hide
+ */
+public class KeyStoreOperation {
+    static final String TAG = "KeyStoreOperation";
+    private final IKeystoreOperation mOperation;
+    private final Long mChallenge;
+    private final KeyParameter[] mParameters;
+
+    public KeyStoreOperation(
+            @NonNull IKeystoreOperation operation,
+            Long challenge,
+            KeyParameter[] parameters
+    ) {
+        this.mOperation = operation;
+        this.mChallenge = challenge;
+        this.mParameters = parameters;
+    }
+
+    /**
+     * Gets the challenge associated with this operation.
+     * @return null if the operation does not required authorization. A 64bit operation
+     *         challenge otherwise.
+     */
+    public Long getChallenge() {
+        return mChallenge;
+    }
+
+    /**
+     * Gets the parameters associated with this operation.
+     * @return
+     */
+    public KeyParameter[] getParameters() {
+        return mParameters;
+    }
+
+    private <R> R handleExceptions(@NonNull CheckedRemoteRequest<R> request)
+            throws KeyStoreException {
+        try {
+            return request.execute();
+        } catch (ServiceSpecificException e) {
+            switch(e.errorCode) {
+                case ResponseCode.OPERATION_BUSY: {
+                    throw new IllegalThreadStateException(
+                            "Cannot update the same operation concurrently."
+                    );
+                }
+                default:
+                    // TODO Human readable string. Use something like KeyStore.getKeyStoreException
+                    throw new KeyStoreException(e.errorCode, "");
+            }
+        } catch (RemoteException e) {
+            // Log exception and report invalid operation handle.
+            // This should prompt the caller drop the reference to this operation and retry.
+            Log.e(
+                    TAG,
+                    "Remote exception while advancing a KeyStoreOperation.",
+                    e
+            );
+            throw new KeyStoreException(KeymasterDefs.KM_ERROR_INVALID_OPERATION_HANDLE, "");
+        }
+    }
+
+    /**
+     * Updates the Keystore operation represented by this object with more associated data.
+     * @see IKeystoreOperation#updateAad(byte[]) for more details.
+     * @param input
+     * @throws KeyStoreException
+     */
+    public void updateAad(@NonNull byte[] input) throws KeyStoreException {
+        handleExceptions(() -> {
+            mOperation.updateAad(input);
+            return 0;
+        });
+    }
+
+    /**
+     * Updates the Keystore operation represented by this object.
+     * @see IKeystoreOperation#update(byte[]) for more details.
+     * @param input
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public byte[] update(@NonNull byte[] input) throws KeyStoreException {
+        return handleExceptions(() -> mOperation.update(input));
+    }
+
+    /**
+     * Finalizes the Keystore operation represented by this object.
+     * @see IKeystoreOperation#finish(byte[], byte[]) for more details.
+     * @param input
+     * @param signature
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public byte[] finish(byte[] input, byte[] signature) throws KeyStoreException {
+        return handleExceptions(() -> mOperation.finish(input, signature));
+    }
+
+    /**
+     * Aborts the Keystore operation represented by this object.
+     * @see IKeystoreOperation#abort() for more details.
+     * @throws KeyStoreException
+     * @hide
+     */
+    public void abort() throws KeyStoreException {
+        handleExceptions(() -> {
+            mOperation.abort();
+            return 0;
+        });
+    }
+}

keystore/java/android/security/KeyStoreSecurityLevel.java

@@ -0,0 +1,217 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security;
+
+import android.annotation.NonNull;
+import android.app.compat.CompatChanges;
+import android.os.RemoteException;
+import android.os.ServiceSpecificException;
+import android.security.keystore.BackendBusyException;
+import android.security.keystore.KeyStoreConnectException;
+import android.system.keystore2.AuthenticatorSpec;
+import android.system.keystore2.CreateOperationResponse;
+import android.system.keystore2.IKeystoreSecurityLevel;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+import android.system.keystore2.KeyParameter;
+import android.system.keystore2.ResponseCode;
+import android.util.Log;
+
+import java.util.Calendar;
+import java.util.Collection;
+
+/**
+ * This is a shim around the security level specific interface of Keystore 2.0. Services with
+ * this interface are instantiated per KeyMint backend, each having there own security level.
+ * Thus this object representation of a security level.
+ * @hide
+ */
+public class KeyStoreSecurityLevel {
+    private static final String TAG = "KeyStoreSecurityLevel";
+    private final IKeystoreSecurityLevel mSecurityLevel;
+
+    public KeyStoreSecurityLevel(IKeystoreSecurityLevel securityLevel) {
+        this.mSecurityLevel = securityLevel;
+    }
+
+    private <R> R handleExceptions(CheckedRemoteRequest<R> request) throws KeyStoreException {
+        try {
+            return request.execute();
+        } catch (ServiceSpecificException e) {
+            throw new KeyStoreException(e.errorCode, "");
+        } catch (RemoteException e) {
+            // Log exception and report invalid operation handle.
+            // This should prompt the caller drop the reference to this operation and retry.
+            Log.e(TAG, "Could not connect to Keystore.", e);
+            throw new KeyStoreException(ResponseCode.SYSTEM_ERROR, "");
+        }
+    }
+
+    /**
+     * Creates a new keystore operation.
+     * @see IKeystoreSecurityLevel#createOperation(KeyDescriptor, KeyParameter[], boolean) for more
+     * details.
+     * @param keyDescriptor
+     * @param args
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyStoreOperation createOperation(@NonNull KeyDescriptor keyDescriptor,
+            Collection<KeyParameter> args) throws KeyStoreException {
+        while (true) {
+            try {
+                CreateOperationResponse createOperationResponse =
+                        mSecurityLevel.createOperation(
+                                keyDescriptor,
+                                args.toArray(new KeyParameter[args.size()]),
+                                false /* forced */
+                        );
+                Long challenge = null;
+                if (createOperationResponse.operationChallenge != null) {
+                    challenge = createOperationResponse.operationChallenge.challenge;
+                }
+                KeyParameter[] parameters = null;
+                if (createOperationResponse.parameters != null) {
+                    parameters = createOperationResponse.parameters.keyParameter;
+                }
+                return new KeyStoreOperation(
+                        createOperationResponse.iOperation,
+                        challenge,
+                        parameters);
+            } catch (ServiceSpecificException e) {
+                switch (e.errorCode) {
+                    case ResponseCode.BACKEND_BUSY: {
+                        if (CompatChanges.isChangeEnabled(
+                                KeyStore2.KEYSTORE_OPERATION_CREATION_MAY_FAIL)) {
+                            // Starting with Android S we inform the caller about the
+                            // backend being busy.
+                            throw new BackendBusyException();
+                        } else {
+                            // Before Android S operation creation must always succeed. So we
+                            // just have to retry. We do so with a randomized back-off between
+                            // 50 and 250ms.
+                            // It is a little awkward that we cannot break out of this loop
+                            // by interrupting this thread. But that is the expected behavior.
+                            // There is some comfort in the fact that interrupting a thread
+                            // also does not unblock a thread waiting for a binder transaction.
+                            interruptedPreservingSleep((long) (Math.random() * 200 + 50));
+                        }
+                        break;
+                    }
+                    default:
+                        throw new KeyStoreException(e.errorCode, "");
+                }
+            } catch (RemoteException e) {
+                Log.w(TAG, "Cannot connect to keystore", e);
+                throw new KeyStoreConnectException();
+            }
+        }
+    }
+
+    /**
+     * Generates a new key in Keystore.
+     * @see IKeystoreSecurityLevel#generateKey(KeyDescriptor, KeyDescriptor, KeyParameter[], int,
+     * byte[]) for more details.
+     * @param descriptor
+     * @param attestationKey
+     * @param args
+     * @param flags
+     * @param entropy
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyMetadata generateKey(@NonNull KeyDescriptor descriptor, KeyDescriptor attestationKey,
+            Collection<KeyParameter> args, int flags, byte[] entropy)
+            throws KeyStoreException {
+        return handleExceptions(() -> mSecurityLevel.generateKey(
+                descriptor, attestationKey, args.toArray(new KeyParameter[args.size()]),
+                flags, entropy));
+    }
+
+    /**
+     * Imports a key into Keystore.
+     * @see IKeystoreSecurityLevel#importKey(KeyDescriptor, KeyDescriptor, KeyParameter[], int,
+     * byte[]) for more details.
+     * @param descriptor
+     * @param attestationKey
+     * @param args
+     * @param flags
+     * @param keyData
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyMetadata importKey(KeyDescriptor descriptor, KeyDescriptor attestationKey,
+            Collection<KeyParameter> args, int flags, byte[] keyData)
+            throws KeyStoreException {
+        return handleExceptions(() -> mSecurityLevel.importKey(descriptor, attestationKey,
+                args.toArray(new KeyParameter[args.size()]), flags, keyData));
+    }
+
+    /**
+     * Imports a wrapped key into Keystore.
+     * @see IKeystoreSecurityLevel#importWrappedKey(KeyDescriptor, KeyDescriptor, byte[],
+     * KeyParameter[], AuthenticatorSpec[]) for more details.
+     * @param wrappedKeyDescriptor
+     * @param wrappingKeyDescriptor
+     * @param wrappedKey
+     * @param maskingKey
+     * @param args
+     * @param authenticatorSpecs
+     * @return
+     * @throws KeyStoreException
+     * @hide
+     */
+    public KeyMetadata importWrappedKey(@NonNull KeyDescriptor wrappedKeyDescriptor,
+            @NonNull KeyDescriptor wrappingKeyDescriptor,
+            @NonNull byte[] wrappedKey, byte[] maskingKey,
+            Collection<KeyParameter> args, @NonNull AuthenticatorSpec[] authenticatorSpecs)
+            throws KeyStoreException {
+        KeyDescriptor keyDescriptor = new KeyDescriptor();
+        keyDescriptor.alias = wrappedKeyDescriptor.alias;
+        keyDescriptor.nspace = wrappedKeyDescriptor.nspace;
+        keyDescriptor.blob = wrappedKey;
+        keyDescriptor.domain = wrappedKeyDescriptor.domain;
+
+        return handleExceptions(() -> mSecurityLevel.importWrappedKey(wrappedKeyDescriptor,
+                wrappingKeyDescriptor, maskingKey,
+                args.toArray(new KeyParameter[args.size()]), authenticatorSpecs));
+    }
+
+    protected static void interruptedPreservingSleep(long millis) {
+        boolean wasInterrupted = false;
+        Calendar calendar = Calendar.getInstance();
+        long target = calendar.getTimeInMillis() + millis;
+        while (true) {
+            try {
+                Thread.sleep(target - calendar.getTimeInMillis());
+                break;
+            } catch (InterruptedException e) {
+                wasInterrupted = true;
+            } catch (IllegalArgumentException e) {
+                // This means that the argument to sleep was negative.
+                // So we are done sleeping.
+                break;
+            }
+        }
+        if (wasInterrupted) {
+            Thread.currentThread().interrupt();
+        }
+    }
+}

keystore/java/android/security/keystore/AndroidKeyStoreBCWorkaroundProvider.java

@@ -34,7 +34,7 @@ import java.security.Provider;
  *
  * @hide
  */
-class AndroidKeyStoreBCWorkaroundProvider extends Provider {
+public class AndroidKeyStoreBCWorkaroundProvider extends Provider {
 
     // IMPLEMENTATION NOTE: Class names are hard-coded in this provider to avoid loading these
     // classes when this provider is instantiated and installed early on during each app's
@@ -50,8 +50,14 @@ class AndroidKeyStoreBCWorkaroundProvider extends Provider {
 
     private static final String DESEDE_SYSTEM_PROPERTY = "ro.hardware.keystore_desede";
 
-    AndroidKeyStoreBCWorkaroundProvider() {
-        super("AndroidKeyStoreBCWorkaround",
+    /** @hide */
+    public AndroidKeyStoreBCWorkaroundProvider() {
+        this("AndroidKeyStoreBCWorkaround");
+    }
+
+    /** @hide **/
+    public AndroidKeyStoreBCWorkaroundProvider(String providerName) {
+        super(providerName,
                 1.0,
                 "Android KeyStore security provider to work around Bouncy Castle");
 

keystore/java/android/security/keystore/AndroidKeyStoreProvider.java

@@ -71,14 +71,20 @@ public class AndroidKeyStoreProvider extends Provider {
     private static final String DESEDE_SYSTEM_PROPERTY =
             "ro.hardware.keystore_desede";
 
-    /** @hide **/
+    /** @hide */
     public AndroidKeyStoreProvider() {
-        super(PROVIDER_NAME, 1.0, "Android KeyStore security provider");
+        this(PROVIDER_NAME);
+    }
+
+    /** @hide **/
+    public AndroidKeyStoreProvider(String providerName) {
+        super(providerName, 1.0, "Android KeyStore security provider");
 
         boolean supports3DES = "true".equals(android.os.SystemProperties.get(DESEDE_SYSTEM_PROPERTY));
 
         // java.security.KeyStore
         put("KeyStore.AndroidKeyStore", PACKAGE_NAME + ".AndroidKeyStoreSpi");
+        put("alg.alias.KeyStore.AndroidKeyStoreLegacy", "AndroidKeyStore");
 
         // java.security.KeyPairGenerator
         put("KeyPairGenerator.EC", PACKAGE_NAME + ".AndroidKeyStoreKeyPairGeneratorSpi$EC");
@@ -438,8 +444,12 @@ public class AndroidKeyStoreProvider extends Provider {
     @NonNull
     public static java.security.KeyStore getKeyStoreForUid(int uid)
             throws KeyStoreException, NoSuchProviderException {
+        String providerName = PROVIDER_NAME;
+        if (android.security.keystore2.AndroidKeyStoreProvider.isInstalled()) {
+            providerName = "AndroidKeyStoreLegacy";
+        }
         java.security.KeyStore result =
-                java.security.KeyStore.getInstance("AndroidKeyStore", PROVIDER_NAME);
+                java.security.KeyStore.getInstance(providerName);
         try {
             result.load(new AndroidKeyStoreLoadStoreParameter(uid));
         } catch (NoSuchAlgorithmException | CertificateException | IOException e) {

keystore/java/android/security/keystore/BackendBusyException.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore;
+
+import android.annotation.NonNull;
+
+import java.security.ProviderException;
+
+/**
+ * Indicates a transient error that prevented a key operation from being created.
+ * Callers should try again with a back-off period of 10-30 milliseconds.
+ */
+public class BackendBusyException extends ProviderException {
+
+    /**
+     * Constructs a new {@code BackendBusyException} without detail message and cause.
+     */
+    public BackendBusyException() {
+        super("The keystore backend has no operation slots available. Retry later.");
+    }
+
+    /**
+     * Constructs a new {@code BackendBusyException} with the provided detail message and
+     * no cause.
+     */
+    public BackendBusyException(@NonNull String message) {
+        super(message);
+    }
+
+    /**
+     * Constructs a new {@code BackendBusyException} with the provided detail message and
+     * cause.
+     */
+    public BackendBusyException(@NonNull String message, @NonNull Throwable cause) {
+        super(message, cause);
+    }
+
+}

keystore/java/android/security/keystore2/AndroidKeyStore3DESCipherSpi.java

@@ -0,0 +1,317 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.KeyParameter;
+
+import java.security.AlgorithmParameters;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.Key;
+import java.security.NoSuchAlgorithmException;
+import java.security.ProviderException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidParameterSpecException;
+import java.util.Arrays;
+import java.util.List;
+
+import javax.crypto.CipherSpi;
+import javax.crypto.spec.IvParameterSpec;
+
+/**
+ * Base class for Android Keystore 3DES {@link CipherSpi} implementations.
+ *
+ * @hide
+ */
+public class AndroidKeyStore3DESCipherSpi extends AndroidKeyStoreCipherSpiBase {
+
+    private static final int BLOCK_SIZE_BYTES = 8;
+
+    private final int mKeymasterBlockMode;
+    private final int mKeymasterPadding;
+    /** Whether this transformation requires an IV. */
+    private final boolean mIvRequired;
+
+    private byte[] mIv;
+
+    /** Whether the current {@code #mIv} has been used by the underlying crypto operation. */
+    private boolean mIvHasBeenUsed;
+
+    AndroidKeyStore3DESCipherSpi(
+            int keymasterBlockMode,
+            int keymasterPadding,
+            boolean ivRequired) {
+        mKeymasterBlockMode = keymasterBlockMode;
+        mKeymasterPadding = keymasterPadding;
+        mIvRequired = ivRequired;
+    }
+
+    abstract static class ECB extends AndroidKeyStore3DESCipherSpi {
+        protected ECB(int keymasterPadding) {
+            super(KeymasterDefs.KM_MODE_ECB, keymasterPadding, false);
+        }
+
+        public static class NoPadding extends ECB {
+            public NoPadding() {
+                super(KeymasterDefs.KM_PAD_NONE);
+            }
+        }
+
+        public static class PKCS7Padding extends ECB {
+            public PKCS7Padding() {
+                super(KeymasterDefs.KM_PAD_PKCS7);
+            }
+        }
+    }
+
+    abstract static class CBC extends AndroidKeyStore3DESCipherSpi {
+        protected CBC(int keymasterPadding) {
+            super(KeymasterDefs.KM_MODE_CBC, keymasterPadding, true);
+        }
+
+        public static class NoPadding extends CBC {
+            public NoPadding() {
+                super(KeymasterDefs.KM_PAD_NONE);
+            }
+        }
+
+        public static class PKCS7Padding extends CBC {
+            public PKCS7Padding() {
+                super(KeymasterDefs.KM_PAD_PKCS7);
+            }
+        }
+    }
+
+    @Override
+    protected void initKey(int i, Key key) throws InvalidKeyException {
+        if (!(key instanceof AndroidKeyStoreSecretKey)) {
+            throw new InvalidKeyException(
+                    "Unsupported key: " + ((key != null) ? key.getClass().getName() : "null"));
+        }
+        if (!KeyProperties.KEY_ALGORITHM_3DES.equalsIgnoreCase(key.getAlgorithm())) {
+            throw new InvalidKeyException(
+                    "Unsupported key algorithm: " + key.getAlgorithm() + ". Only " +
+                            KeyProperties.KEY_ALGORITHM_3DES + " supported");
+        }
+        setKey((AndroidKeyStoreSecretKey) key);
+    }
+
+    @Override
+    protected int engineGetBlockSize() {
+        return BLOCK_SIZE_BYTES;
+    }
+
+    @Override
+    protected int engineGetOutputSize(int inputLen) {
+        return inputLen + 3 * BLOCK_SIZE_BYTES;
+    }
+
+    @Override
+    protected final byte[] engineGetIV() {
+        return ArrayUtils.cloneIfNotEmpty(mIv);
+    }
+
+    @Override
+    protected AlgorithmParameters engineGetParameters() {
+        if (!mIvRequired) {
+            return null;
+        }
+        if ((mIv != null) && (mIv.length > 0)) {
+            try {
+                AlgorithmParameters params = AlgorithmParameters.getInstance("DESede");
+                params.init(new IvParameterSpec(mIv));
+                return params;
+            } catch (NoSuchAlgorithmException e) {
+                throw new ProviderException(
+                        "Failed to obtain 3DES AlgorithmParameters", e);
+            } catch (InvalidParameterSpecException e) {
+                throw new ProviderException(
+                        "Failed to initialize 3DES AlgorithmParameters with an IV",
+                        e);
+            }
+        }
+        return null;
+    }
+
+    @Override
+    protected void initAlgorithmSpecificParameters() throws InvalidKeyException {
+        if (!mIvRequired) {
+            return;
+        }
+
+        // IV is used
+        if (!isEncrypting()) {
+            throw new InvalidKeyException("IV required when decrypting"
+                    + ". Use IvParameterSpec or AlgorithmParameters to provide it.");
+        }
+    }
+
+    @Override
+    protected void initAlgorithmSpecificParameters(AlgorithmParameterSpec params)
+            throws InvalidAlgorithmParameterException {
+        if (!mIvRequired) {
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);
+            }
+            return;
+        }
+
+        // IV is used
+        if (params == null) {
+            if (!isEncrypting()) {
+                // IV must be provided by the caller
+                throw new InvalidAlgorithmParameterException(
+                        "IvParameterSpec must be provided when decrypting");
+            }
+            return;
+        }
+        if (!(params instanceof IvParameterSpec)) {
+            throw new InvalidAlgorithmParameterException("Only IvParameterSpec supported");
+        }
+        mIv = ((IvParameterSpec) params).getIV();
+        if (mIv == null) {
+            throw new InvalidAlgorithmParameterException("Null IV in IvParameterSpec");
+        }
+    }
+
+    @Override
+    protected void initAlgorithmSpecificParameters(AlgorithmParameters params)
+            throws InvalidAlgorithmParameterException {
+        if (!mIvRequired) {
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);
+            }
+            return;
+        }
+
+        // IV is used
+        if (params == null) {
+            if (!isEncrypting()) {
+                // IV must be provided by the caller
+                throw new InvalidAlgorithmParameterException("IV required when decrypting"
+                        + ". Use IvParameterSpec or AlgorithmParameters to provide it.");
+            }
+            return;
+        }
+
+        if (!"DESede".equalsIgnoreCase(params.getAlgorithm())) {
+            throw new InvalidAlgorithmParameterException(
+                    "Unsupported AlgorithmParameters algorithm: " + params.getAlgorithm()
+                            + ". Supported: DESede");
+        }
+
+        IvParameterSpec ivSpec;
+        try {
+            ivSpec = params.getParameterSpec(IvParameterSpec.class);
+        } catch (InvalidParameterSpecException e) {
+            if (!isEncrypting()) {
+                // IV must be provided by the caller
+                throw new InvalidAlgorithmParameterException("IV required when decrypting"
+                        + ", but not found in parameters: " + params, e);
+            }
+            mIv = null;
+            return;
+        }
+        mIv = ivSpec.getIV();
+        if (mIv == null) {
+            throw new InvalidAlgorithmParameterException("Null IV in AlgorithmParameters");
+        }
+    }
+
+    @Override
+    protected final int getAdditionalEntropyAmountForBegin() {
+        if ((mIvRequired) && (mIv == null) && (isEncrypting())) {
+            // IV will need to be generated
+            return BLOCK_SIZE_BYTES;
+        }
+
+        return 0;
+    }
+
+    @Override
+    protected int getAdditionalEntropyAmountForFinish() {
+        return 0;
+    }
+
+    @Override
+    protected void addAlgorithmSpecificParametersToBegin(@NonNull List<KeyParameter> parameters) {
+        if ((isEncrypting()) && (mIvRequired) && (mIvHasBeenUsed)) {
+            // IV is being reused for encryption: this violates security best practices.
+            throw new IllegalStateException(
+                    "IV has already been used. Reusing IV in encryption mode violates security best"
+                            + " practices.");
+        }
+
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM,
+                KeymasterDefs.KM_ALGORITHM_3DES
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_BLOCK_MODE,
+                mKeymasterBlockMode
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_PADDING,
+                mKeymasterPadding
+        ));
+
+        if (mIvRequired && (mIv != null)) {
+            parameters.add(KeyStore2ParameterUtils.makeBytes(KeymasterDefs.KM_TAG_NONCE, mIv));
+        }
+    }
+
+    @Override
+    protected void loadAlgorithmSpecificParametersFromBeginResult(
+            KeyParameter[] parameters) {
+        mIvHasBeenUsed = true;
+
+        // NOTE: Keymaster doesn't always return an IV, even if it's used.
+        byte[] returnedIv = null;
+        if (parameters != null) {
+            for (KeyParameter p : parameters) {
+                if (p.tag == KeymasterDefs.KM_TAG_NONCE) {
+                    returnedIv = p.blob;
+                    break;
+                }
+            }
+        }
+
+        if (mIvRequired) {
+            if (mIv == null) {
+                mIv = returnedIv;
+            } else if ((returnedIv != null) && (!Arrays.equals(returnedIv, mIv))) {
+                throw new ProviderException("IV in use differs from provided IV");
+            }
+        } else {
+            if (returnedIv != null) {
+                throw new ProviderException(
+                        "IV in use despite IV not being used by this transformation");
+            }
+        }
+    }
+
+    @Override
+    protected final void resetAll() {
+        mIv = null;
+        mIvHasBeenUsed = false;
+        super.resetAll();
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreAuthenticatedAESCipherSpi.java

@@ -0,0 +1,439 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+import android.security.keystore.KeyProperties;
+import android.security.keystore2.KeyStoreCryptoOperationChunkedStreamer.Stream;
+import android.system.keystore2.KeyParameter;
+
+import libcore.util.EmptyArray;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.security.AlgorithmParameters;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.Key;
+import java.security.NoSuchAlgorithmException;
+import java.security.ProviderException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidParameterSpecException;
+import java.util.Arrays;
+import java.util.List;
+
+import javax.crypto.CipherSpi;
+import javax.crypto.spec.GCMParameterSpec;
+
+/**
+ * Base class for Android Keystore authenticated AES {@link CipherSpi} implementations.
+ *
+ * @hide
+ */
+abstract class AndroidKeyStoreAuthenticatedAESCipherSpi extends AndroidKeyStoreCipherSpiBase {
+
+    abstract static class GCM extends AndroidKeyStoreAuthenticatedAESCipherSpi {
+        static final int MIN_SUPPORTED_TAG_LENGTH_BITS = 96;
+        private static final int MAX_SUPPORTED_TAG_LENGTH_BITS = 128;
+        private static final int DEFAULT_TAG_LENGTH_BITS = 128;
+        private static final int IV_LENGTH_BYTES = 12;
+
+        private int mTagLengthBits = DEFAULT_TAG_LENGTH_BITS;
+
+        GCM(int keymasterPadding) {
+            super(KeymasterDefs.KM_MODE_GCM, keymasterPadding);
+        }
+
+        @Override
+        protected final void resetAll() {
+            mTagLengthBits = DEFAULT_TAG_LENGTH_BITS;
+            super.resetAll();
+        }
+
+        @Override
+        protected final void resetWhilePreservingInitState() {
+            super.resetWhilePreservingInitState();
+        }
+
+        @Override
+        protected final void initAlgorithmSpecificParameters() throws InvalidKeyException {
+            if (!isEncrypting()) {
+                throw new InvalidKeyException("IV required when decrypting"
+                        + ". Use IvParameterSpec or AlgorithmParameters to provide it.");
+            }
+        }
+
+        @Override
+        protected final void initAlgorithmSpecificParameters(AlgorithmParameterSpec params)
+                throws InvalidAlgorithmParameterException {
+            // IV is used
+            if (params == null) {
+                if (!isEncrypting()) {
+                    // IV must be provided by the caller
+                    throw new InvalidAlgorithmParameterException(
+                            "GCMParameterSpec must be provided when decrypting");
+                }
+                return;
+            }
+            if (!(params instanceof GCMParameterSpec)) {
+                throw new InvalidAlgorithmParameterException("Only GCMParameterSpec supported");
+            }
+            GCMParameterSpec spec = (GCMParameterSpec) params;
+            byte[] iv = spec.getIV();
+            if (iv == null) {
+                throw new InvalidAlgorithmParameterException("Null IV in GCMParameterSpec");
+            } else if (iv.length != IV_LENGTH_BYTES) {
+                throw new InvalidAlgorithmParameterException("Unsupported IV length: "
+                        + iv.length + " bytes. Only " + IV_LENGTH_BYTES
+                        + " bytes long IV supported");
+            }
+            int tagLengthBits = spec.getTLen();
+            if ((tagLengthBits < MIN_SUPPORTED_TAG_LENGTH_BITS)
+                    || (tagLengthBits > MAX_SUPPORTED_TAG_LENGTH_BITS)
+                    || ((tagLengthBits % 8) != 0)) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported tag length: " + tagLengthBits + " bits"
+                        + ". Supported lengths: 96, 104, 112, 120, 128");
+            }
+            setIv(iv);
+            mTagLengthBits = tagLengthBits;
+        }
+
+        @Override
+        protected final void initAlgorithmSpecificParameters(AlgorithmParameters params)
+                throws InvalidAlgorithmParameterException {
+            if (params == null) {
+                if (!isEncrypting()) {
+                    // IV must be provided by the caller
+                    throw new InvalidAlgorithmParameterException("IV required when decrypting"
+                            + ". Use GCMParameterSpec or GCM AlgorithmParameters to provide it.");
+                }
+                return;
+            }
+
+            if (!"GCM".equalsIgnoreCase(params.getAlgorithm())) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported AlgorithmParameters algorithm: " + params.getAlgorithm()
+                        + ". Supported: GCM");
+            }
+
+            GCMParameterSpec spec;
+            try {
+                spec = params.getParameterSpec(GCMParameterSpec.class);
+            } catch (InvalidParameterSpecException e) {
+                if (!isEncrypting()) {
+                    // IV must be provided by the caller
+                    throw new InvalidAlgorithmParameterException("IV and tag length required when"
+                            + " decrypting, but not found in parameters: " + params, e);
+                }
+                setIv(null);
+                return;
+            }
+            initAlgorithmSpecificParameters(spec);
+        }
+
+        @Nullable
+        @Override
+        protected final AlgorithmParameters engineGetParameters() {
+            byte[] iv = getIv();
+            if ((iv != null) && (iv.length > 0)) {
+                try {
+                    AlgorithmParameters params = AlgorithmParameters.getInstance("GCM");
+                    params.init(new GCMParameterSpec(mTagLengthBits, iv));
+                    return params;
+                } catch (NoSuchAlgorithmException e) {
+                    throw new ProviderException(
+                            "Failed to obtain GCM AlgorithmParameters", e);
+                } catch (InvalidParameterSpecException e) {
+                    throw new ProviderException(
+                            "Failed to initialize GCM AlgorithmParameters", e);
+                }
+            }
+            return null;
+        }
+
+        @NonNull
+        @Override
+        protected KeyStoreCryptoOperationStreamer createMainDataStreamer(
+                KeyStoreOperation operation) {
+            KeyStoreCryptoOperationStreamer streamer = new KeyStoreCryptoOperationChunkedStreamer(
+                    new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(
+                            operation), 0);
+            if (isEncrypting()) {
+                return streamer;
+            } else {
+                // When decrypting, to avoid leaking unauthenticated plaintext, do not return any
+                // plaintext before ciphertext is authenticated by KeyStore.finish.
+                return new BufferAllOutputUntilDoFinalStreamer(streamer);
+            }
+        }
+
+        @NonNull
+        @Override
+        protected final KeyStoreCryptoOperationStreamer createAdditionalAuthenticationDataStreamer(
+                KeyStoreOperation operation) {
+            return new KeyStoreCryptoOperationChunkedStreamer(
+                    new AdditionalAuthenticationDataStream(operation), 0);
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForBegin() {
+            if ((getIv() == null) && (isEncrypting())) {
+                // IV will need to be generated
+                return IV_LENGTH_BYTES;
+            }
+
+            return 0;
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForFinish() {
+            return 0;
+        }
+
+        @Override
+        protected final void addAlgorithmSpecificParametersToBegin(
+                @NonNull List<KeyParameter> parameters) {
+            super.addAlgorithmSpecificParametersToBegin(parameters);
+            parameters.add(KeyStore2ParameterUtils.makeInt(
+                    KeymasterDefs.KM_TAG_MAC_LENGTH,
+                    mTagLengthBits
+            ));
+        }
+
+        protected final int getTagLengthBits() {
+            return mTagLengthBits;
+        }
+
+        public static final class NoPadding extends GCM {
+            public NoPadding() {
+                super(KeymasterDefs.KM_PAD_NONE);
+            }
+
+            @Override
+            protected final int engineGetOutputSize(int inputLen) {
+                int tagLengthBytes = (getTagLengthBits() + 7) / 8;
+                long result;
+                if (isEncrypting()) {
+                    result = getConsumedInputSizeBytes() - getProducedOutputSizeBytes() + inputLen
+                            + tagLengthBytes;
+                } else {
+                    result = getConsumedInputSizeBytes() - getProducedOutputSizeBytes() + inputLen
+                            - tagLengthBytes;
+                }
+                if (result < 0) {
+                    return 0;
+                } else if (result > Integer.MAX_VALUE) {
+                    return Integer.MAX_VALUE;
+                }
+                return (int) result;
+            }
+        }
+    }
+
+    private static final int BLOCK_SIZE_BYTES = 16;
+
+    private final int mKeymasterBlockMode;
+    private final int mKeymasterPadding;
+
+    private byte[] mIv;
+
+    /** Whether the current {@code #mIv} has been used by the underlying crypto operation. */
+    private boolean mIvHasBeenUsed;
+
+    AndroidKeyStoreAuthenticatedAESCipherSpi(
+            int keymasterBlockMode,
+            int keymasterPadding) {
+        mKeymasterBlockMode = keymasterBlockMode;
+        mKeymasterPadding = keymasterPadding;
+    }
+
+    @Override
+    protected void resetAll() {
+        mIv = null;
+        mIvHasBeenUsed = false;
+        super.resetAll();
+    }
+
+    @Override
+    protected final void initKey(int opmode, Key key) throws InvalidKeyException {
+        if (!(key instanceof AndroidKeyStoreSecretKey)) {
+            throw new InvalidKeyException(
+                    "Unsupported key: " + ((key != null) ? key.getClass().getName() : "null"));
+        }
+        if (!KeyProperties.KEY_ALGORITHM_AES.equalsIgnoreCase(key.getAlgorithm())) {
+            throw new InvalidKeyException(
+                    "Unsupported key algorithm: " + key.getAlgorithm() + ". Only " +
+                    KeyProperties.KEY_ALGORITHM_AES + " supported");
+        }
+        setKey((AndroidKeyStoreSecretKey) key);
+    }
+
+    @Override
+    protected void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters) {
+        if ((isEncrypting()) && (mIvHasBeenUsed)) {
+            // IV is being reused for encryption: this violates security best practices.
+            throw new IllegalStateException(
+                    "IV has already been used. Reusing IV in encryption mode violates security best"
+                    + " practices.");
+        }
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM,
+                KeymasterDefs.KM_ALGORITHM_AES
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_BLOCK_MODE,
+                mKeymasterBlockMode
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_PADDING,
+                mKeymasterPadding
+        ));
+
+        if (mIv != null) {
+            parameters.add(KeyStore2ParameterUtils.makeBytes(KeymasterDefs.KM_TAG_NONCE, mIv));
+        }
+    }
+
+    @Override
+    protected final void loadAlgorithmSpecificParametersFromBeginResult(
+            KeyParameter[] parameters) {
+        mIvHasBeenUsed = true;
+
+        // NOTE: Keymaster doesn't always return an IV, even if it's used.
+        byte[] returnedIv = null;
+        if (parameters != null) {
+            for (KeyParameter p : parameters) {
+                if (p.tag == KeymasterDefs.KM_TAG_NONCE) {
+                    returnedIv = p.blob;
+                    break;
+                }
+            }
+        }
+
+        if (mIv == null) {
+            mIv = returnedIv;
+        } else if ((returnedIv != null) && (!Arrays.equals(returnedIv, mIv))) {
+            throw new ProviderException("IV in use differs from provided IV");
+        }
+    }
+
+    @Override
+    protected final int engineGetBlockSize() {
+        return BLOCK_SIZE_BYTES;
+    }
+
+    @Override
+    protected final byte[] engineGetIV() {
+        return ArrayUtils.cloneIfNotEmpty(mIv);
+    }
+
+    protected void setIv(byte[] iv) {
+        mIv = iv;
+    }
+
+    protected byte[] getIv() {
+        return mIv;
+    }
+
+    /**
+     * {@link KeyStoreCryptoOperationStreamer} which buffers all output until {@code doFinal} from
+     * which it returns all output in one go, provided {@code doFinal} succeeds.
+     */
+    private static class BufferAllOutputUntilDoFinalStreamer
+        implements KeyStoreCryptoOperationStreamer {
+
+        private final KeyStoreCryptoOperationStreamer mDelegate;
+        private ByteArrayOutputStream mBufferedOutput = new ByteArrayOutputStream();
+        private long mProducedOutputSizeBytes;
+
+        private BufferAllOutputUntilDoFinalStreamer(KeyStoreCryptoOperationStreamer delegate) {
+            mDelegate = delegate;
+        }
+
+        @Override
+        public byte[] update(byte[] input, int inputOffset, int inputLength)
+                throws KeyStoreException {
+            byte[] output = mDelegate.update(input, inputOffset, inputLength);
+            if (output != null) {
+                try {
+                    mBufferedOutput.write(output);
+                } catch (IOException e) {
+                    throw new ProviderException("Failed to buffer output", e);
+                }
+            }
+            return EmptyArray.BYTE;
+        }
+
+        @Override
+        public byte[] doFinal(byte[] input, int inputOffset, int inputLength,
+                byte[] signature) throws KeyStoreException {
+            byte[] output = mDelegate.doFinal(input, inputOffset, inputLength, signature);
+            if (output != null) {
+                try {
+                    mBufferedOutput.write(output);
+                } catch (IOException e) {
+                    throw new ProviderException("Failed to buffer output", e);
+                }
+            }
+            byte[] result = mBufferedOutput.toByteArray();
+            mBufferedOutput.reset();
+            mProducedOutputSizeBytes += result.length;
+            return result;
+        }
+
+        @Override
+        public long getConsumedInputSizeBytes() {
+            return mDelegate.getConsumedInputSizeBytes();
+        }
+
+        @Override
+        public long getProducedOutputSizeBytes() {
+            return mProducedOutputSizeBytes;
+        }
+    }
+
+    /**
+     * Additional Authentication Data (AAD) stream via a KeyStore streaming operation. This stream
+     * sends AAD into the KeyStore.
+     */
+    private static class AdditionalAuthenticationDataStream implements Stream {
+
+        private final KeyStoreOperation mOperation;
+
+        private AdditionalAuthenticationDataStream(KeyStoreOperation operation) {
+            mOperation = operation;
+        }
+
+        @Override
+        public byte[] update(byte[] input) throws KeyStoreException {
+            mOperation.updateAad(input);
+            return null;
+        }
+
+        @Override
+        public byte[] finish(byte[] input, byte[] signature) {
+            return null;
+        }
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreBCWorkaroundProvider.java

@@ -0,0 +1,273 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import java.security.Provider;
+
+/**
+ * {@link Provider} of JCA crypto operations operating on Android KeyStore keys.
+ *
+ * <p>This provider was separated out of {@link AndroidKeyStoreProvider} to work around the issue
+ * that Bouncy Castle provider incorrectly declares that it accepts arbitrary keys (incl. Android
+ * KeyStore ones). This causes JCA to select the Bouncy Castle's implementation of JCA crypto
+ * operations for Android KeyStore keys unless Android KeyStore's own implementations are installed
+ * as higher-priority than Bouncy Castle ones. The purpose of this provider is to do just that: to
+ * offer crypto operations operating on Android KeyStore keys and to be installed at higher priority
+ * than the Bouncy Castle provider.
+ *
+ * <p>Once Bouncy Castle provider is fixed, this provider can be merged into the
+ * {@code AndroidKeyStoreProvider}.
+ *
+ * @hide
+ */
+class AndroidKeyStoreBCWorkaroundProvider extends Provider {
+
+    // IMPLEMENTATION NOTE: Class names are hard-coded in this provider to avoid loading these
+    // classes when this provider is instantiated and installed early on during each app's
+    // initialization process.
+
+    private static final String PACKAGE_NAME = "android.security.keystore2";
+    private static final String KEYSTORE_SECRET_KEY_CLASS_NAME =
+            PACKAGE_NAME + ".AndroidKeyStoreSecretKey";
+    private static final String KEYSTORE_PRIVATE_KEY_CLASS_NAME =
+            PACKAGE_NAME + ".AndroidKeyStorePrivateKey";
+    private static final String KEYSTORE_PUBLIC_KEY_CLASS_NAME =
+            PACKAGE_NAME + ".AndroidKeyStorePublicKey";
+
+    private static final String DESEDE_SYSTEM_PROPERTY = "ro.hardware.keystore_desede";
+
+    AndroidKeyStoreBCWorkaroundProvider() {
+        super("AndroidKeyStoreBCWorkaround",
+                1.0,
+                "Android KeyStore security provider to work around Bouncy Castle");
+
+        // --------------------- javax.crypto.Mac
+        putMacImpl("HmacSHA1", PACKAGE_NAME + ".AndroidKeyStoreHmacSpi$HmacSHA1");
+        put("Alg.Alias.Mac.1.2.840.113549.2.7", "HmacSHA1");
+        put("Alg.Alias.Mac.HMAC-SHA1", "HmacSHA1");
+        put("Alg.Alias.Mac.HMAC/SHA1", "HmacSHA1");
+
+        putMacImpl("HmacSHA224", PACKAGE_NAME + ".AndroidKeyStoreHmacSpi$HmacSHA224");
+        put("Alg.Alias.Mac.1.2.840.113549.2.9", "HmacSHA224");
+        put("Alg.Alias.Mac.HMAC-SHA224", "HmacSHA224");
+        put("Alg.Alias.Mac.HMAC/SHA224", "HmacSHA224");
+
+        putMacImpl("HmacSHA256", PACKAGE_NAME + ".AndroidKeyStoreHmacSpi$HmacSHA256");
+        put("Alg.Alias.Mac.1.2.840.113549.2.9", "HmacSHA256");
+        put("Alg.Alias.Mac.HMAC-SHA256", "HmacSHA256");
+        put("Alg.Alias.Mac.HMAC/SHA256", "HmacSHA256");
+
+        putMacImpl("HmacSHA384", PACKAGE_NAME + ".AndroidKeyStoreHmacSpi$HmacSHA384");
+        put("Alg.Alias.Mac.1.2.840.113549.2.10", "HmacSHA384");
+        put("Alg.Alias.Mac.HMAC-SHA384", "HmacSHA384");
+        put("Alg.Alias.Mac.HMAC/SHA384", "HmacSHA384");
+
+        putMacImpl("HmacSHA512", PACKAGE_NAME + ".AndroidKeyStoreHmacSpi$HmacSHA512");
+        put("Alg.Alias.Mac.1.2.840.113549.2.11", "HmacSHA512");
+        put("Alg.Alias.Mac.HMAC-SHA512", "HmacSHA512");
+        put("Alg.Alias.Mac.HMAC/SHA512", "HmacSHA512");
+
+        // --------------------- javax.crypto.Cipher
+        putSymmetricCipherImpl("AES/ECB/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStoreUnauthenticatedAESCipherSpi$ECB$NoPadding");
+        putSymmetricCipherImpl("AES/ECB/PKCS7Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreUnauthenticatedAESCipherSpi$ECB$PKCS7Padding");
+
+        putSymmetricCipherImpl("AES/CBC/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStoreUnauthenticatedAESCipherSpi$CBC$NoPadding");
+        putSymmetricCipherImpl("AES/CBC/PKCS7Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreUnauthenticatedAESCipherSpi$CBC$PKCS7Padding");
+
+        putSymmetricCipherImpl("AES/CTR/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStoreUnauthenticatedAESCipherSpi$CTR$NoPadding");
+
+        if ("true".equals(android.os.SystemProperties.get(DESEDE_SYSTEM_PROPERTY))) {
+            putSymmetricCipherImpl("DESede/CBC/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$CBC$NoPadding");
+            putSymmetricCipherImpl("DESede/CBC/PKCS7Padding",
+                PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$CBC$PKCS7Padding");
+
+            putSymmetricCipherImpl("DESede/ECB/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$ECB$NoPadding");
+            putSymmetricCipherImpl("DESede/ECB/PKCS7Padding",
+                PACKAGE_NAME + ".AndroidKeyStore3DESCipherSpi$ECB$PKCS7Padding");
+        }
+
+        putSymmetricCipherImpl("AES/GCM/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStoreAuthenticatedAESCipherSpi$GCM$NoPadding");
+
+        putAsymmetricCipherImpl("RSA/ECB/NoPadding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$NoPadding");
+        put("Alg.Alias.Cipher.RSA/None/NoPadding", "RSA/ECB/NoPadding");
+        putAsymmetricCipherImpl("RSA/ECB/PKCS1Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$PKCS1Padding");
+        put("Alg.Alias.Cipher.RSA/None/PKCS1Padding", "RSA/ECB/PKCS1Padding");
+        putAsymmetricCipherImpl("RSA/ECB/OAEPPadding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$OAEPWithSHA1AndMGF1Padding");
+        put("Alg.Alias.Cipher.RSA/None/OAEPPadding", "RSA/ECB/OAEPPadding");
+        putAsymmetricCipherImpl("RSA/ECB/OAEPWithSHA-1AndMGF1Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$OAEPWithSHA1AndMGF1Padding");
+        put("Alg.Alias.Cipher.RSA/None/OAEPWithSHA-1AndMGF1Padding",
+                "RSA/ECB/OAEPWithSHA-1AndMGF1Padding");
+        putAsymmetricCipherImpl("RSA/ECB/OAEPWithSHA-224AndMGF1Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$OAEPWithSHA224AndMGF1Padding");
+        put("Alg.Alias.Cipher.RSA/None/OAEPWithSHA-224AndMGF1Padding",
+                "RSA/ECB/OAEPWithSHA-256AndMGF1Padding");
+        putAsymmetricCipherImpl("RSA/ECB/OAEPWithSHA-256AndMGF1Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$OAEPWithSHA256AndMGF1Padding");
+        put("Alg.Alias.Cipher.RSA/None/OAEPWithSHA-256AndMGF1Padding",
+                "RSA/ECB/OAEPWithSHA-256AndMGF1Padding");
+        putAsymmetricCipherImpl("RSA/ECB/OAEPWithSHA-384AndMGF1Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$OAEPWithSHA384AndMGF1Padding");
+        put("Alg.Alias.Cipher.RSA/None/OAEPWithSHA-384AndMGF1Padding",
+                "RSA/ECB/OAEPWithSHA-384AndMGF1Padding");
+        putAsymmetricCipherImpl("RSA/ECB/OAEPWithSHA-512AndMGF1Padding",
+                PACKAGE_NAME + ".AndroidKeyStoreRSACipherSpi$OAEPWithSHA512AndMGF1Padding");
+        put("Alg.Alias.Cipher.RSA/None/OAEPWithSHA-512AndMGF1Padding",
+                "RSA/ECB/OAEPWithSHA-512AndMGF1Padding");
+
+        // --------------------- java.security.Signature
+        putSignatureImpl("NONEwithRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$NONEWithPKCS1Padding");
+
+        putSignatureImpl("MD5withRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$MD5WithPKCS1Padding");
+        put("Alg.Alias.Signature.MD5WithRSAEncryption", "MD5withRSA");
+        put("Alg.Alias.Signature.MD5/RSA", "MD5withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.1.1.4", "MD5withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.2.5with1.2.840.113549.1.1.1", "MD5withRSA");
+
+        putSignatureImpl("SHA1withRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA1WithPKCS1Padding");
+        put("Alg.Alias.Signature.SHA1WithRSAEncryption", "SHA1withRSA");
+        put("Alg.Alias.Signature.SHA1/RSA", "SHA1withRSA");
+        put("Alg.Alias.Signature.SHA-1/RSA", "SHA1withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.1.1.5", "SHA1withRSA");
+        put("Alg.Alias.Signature.1.3.14.3.2.26with1.2.840.113549.1.1.1", "SHA1withRSA");
+        put("Alg.Alias.Signature.1.3.14.3.2.26with1.2.840.113549.1.1.5", "SHA1withRSA");
+        put("Alg.Alias.Signature.1.3.14.3.2.29", "SHA1withRSA");
+
+        putSignatureImpl("SHA224withRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA224WithPKCS1Padding");
+        put("Alg.Alias.Signature.SHA224WithRSAEncryption", "SHA224withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.1.1.11", "SHA224withRSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.4with1.2.840.113549.1.1.1",
+                "SHA224withRSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.4with1.2.840.113549.1.1.11",
+                "SHA224withRSA");
+
+        putSignatureImpl("SHA256withRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA256WithPKCS1Padding");
+        put("Alg.Alias.Signature.SHA256WithRSAEncryption", "SHA256withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.1.1.11", "SHA256withRSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.1with1.2.840.113549.1.1.1",
+                "SHA256withRSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.1with1.2.840.113549.1.1.11",
+                "SHA256withRSA");
+
+        putSignatureImpl("SHA384withRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA384WithPKCS1Padding");
+        put("Alg.Alias.Signature.SHA384WithRSAEncryption", "SHA384withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.1.1.12", "SHA384withRSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.2with1.2.840.113549.1.1.1",
+                "SHA384withRSA");
+
+        putSignatureImpl("SHA512withRSA",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA512WithPKCS1Padding");
+        put("Alg.Alias.Signature.SHA512WithRSAEncryption", "SHA512withRSA");
+        put("Alg.Alias.Signature.1.2.840.113549.1.1.13", "SHA512withRSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.3with1.2.840.113549.1.1.1",
+                "SHA512withRSA");
+
+        putSignatureImpl("SHA1withRSA/PSS",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA1WithPSSPadding");
+        putSignatureImpl("SHA224withRSA/PSS",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA224WithPSSPadding");
+        putSignatureImpl("SHA256withRSA/PSS",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA256WithPSSPadding");
+        putSignatureImpl("SHA384withRSA/PSS",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA384WithPSSPadding");
+        putSignatureImpl("SHA512withRSA/PSS",
+                PACKAGE_NAME + ".AndroidKeyStoreRSASignatureSpi$SHA512WithPSSPadding");
+
+        putSignatureImpl("NONEwithECDSA",
+                PACKAGE_NAME + ".AndroidKeyStoreECDSASignatureSpi$NONE");
+
+        putSignatureImpl("SHA1withECDSA", PACKAGE_NAME + ".AndroidKeyStoreECDSASignatureSpi$SHA1");
+        put("Alg.Alias.Signature.ECDSA", "SHA1withECDSA");
+        put("Alg.Alias.Signature.ECDSAwithSHA1", "SHA1withECDSA");
+        // iso(1) member-body(2) us(840) ansi-x962(10045) signatures(4) ecdsa-with-SHA1(1)
+        put("Alg.Alias.Signature.1.2.840.10045.4.1", "SHA1withECDSA");
+        put("Alg.Alias.Signature.1.3.14.3.2.26with1.2.840.10045.2.1", "SHA1withECDSA");
+
+        // iso(1) member-body(2) us(840) ansi-x962(10045) signatures(4) ecdsa-with-SHA2(3)
+        putSignatureImpl("SHA224withECDSA",
+                PACKAGE_NAME + ".AndroidKeyStoreECDSASignatureSpi$SHA224");
+        // ecdsa-with-SHA224(1)
+        put("Alg.Alias.Signature.1.2.840.10045.4.3.1", "SHA224withECDSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.4with1.2.840.10045.2.1", "SHA224withECDSA");
+
+        // iso(1) member-body(2) us(840) ansi-x962(10045) signatures(4) ecdsa-with-SHA2(3)
+        putSignatureImpl("SHA256withECDSA",
+                PACKAGE_NAME + ".AndroidKeyStoreECDSASignatureSpi$SHA256");
+        // ecdsa-with-SHA256(2)
+        put("Alg.Alias.Signature.1.2.840.10045.4.3.2", "SHA256withECDSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.1with1.2.840.10045.2.1", "SHA256withECDSA");
+
+        putSignatureImpl("SHA384withECDSA",
+                PACKAGE_NAME + ".AndroidKeyStoreECDSASignatureSpi$SHA384");
+        // ecdsa-with-SHA384(3)
+        put("Alg.Alias.Signature.1.2.840.10045.4.3.3", "SHA384withECDSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.2with1.2.840.10045.2.1", "SHA384withECDSA");
+
+        putSignatureImpl("SHA512withECDSA",
+                PACKAGE_NAME + ".AndroidKeyStoreECDSASignatureSpi$SHA512");
+        // ecdsa-with-SHA512(4)
+        put("Alg.Alias.Signature.1.2.840.10045.4.3.4", "SHA512withECDSA");
+        put("Alg.Alias.Signature.2.16.840.1.101.3.4.2.3with1.2.840.10045.2.1", "SHA512withECDSA");
+    }
+
+    private void putMacImpl(String algorithm, String implClass) {
+        put("Mac." + algorithm, implClass);
+        put("Mac." + algorithm + " SupportedKeyClasses", KEYSTORE_SECRET_KEY_CLASS_NAME);
+    }
+
+    private void putSymmetricCipherImpl(String transformation, String implClass) {
+        put("Cipher." + transformation, implClass);
+        put("Cipher." + transformation + " SupportedKeyClasses", KEYSTORE_SECRET_KEY_CLASS_NAME);
+    }
+
+    private void putAsymmetricCipherImpl(String transformation, String implClass) {
+        put("Cipher." + transformation, implClass);
+        put("Cipher." + transformation + " SupportedKeyClasses",
+                KEYSTORE_PRIVATE_KEY_CLASS_NAME + "|" + KEYSTORE_PUBLIC_KEY_CLASS_NAME);
+    }
+
+    private void putSignatureImpl(String algorithm, String implClass) {
+        put("Signature." + algorithm, implClass);
+        put("Signature." + algorithm + " SupportedKeyClasses",
+                KEYSTORE_PRIVATE_KEY_CLASS_NAME + "|" + KEYSTORE_PUBLIC_KEY_CLASS_NAME);
+    }
+
+    public static String[] getSupportedEcdsaSignatureDigests() {
+        return new String[] {"NONE", "SHA-1", "SHA-224", "SHA-256", "SHA-384", "SHA-512"};
+    }
+
+    public static String[] getSupportedRsaSignatureWithPkcs1PaddingDigests() {
+        return new String[] {"NONE", "MD5", "SHA-1", "SHA-224", "SHA-256", "SHA-384", "SHA-512"};
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreCipherSpiBase.java

@@ -0,0 +1,905 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.CallSuper;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyStoreCryptoOperation;
+import android.system.keystore2.KeyParameter;
+
+import libcore.util.EmptyArray;
+
+import java.nio.BufferOverflowException;
+import java.nio.ByteBuffer;
+import java.security.AlgorithmParameters;
+import java.security.GeneralSecurityException;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.InvalidParameterException;
+import java.security.Key;
+import java.security.KeyFactory;
+import java.security.NoSuchAlgorithmException;
+import java.security.PrivateKey;
+import java.security.ProviderException;
+import java.security.PublicKey;
+import java.security.SecureRandom;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.PKCS8EncodedKeySpec;
+import java.security.spec.X509EncodedKeySpec;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.crypto.AEADBadTagException;
+import javax.crypto.BadPaddingException;
+import javax.crypto.Cipher;
+import javax.crypto.CipherSpi;
+import javax.crypto.IllegalBlockSizeException;
+import javax.crypto.NoSuchPaddingException;
+import javax.crypto.SecretKey;
+import javax.crypto.SecretKeyFactory;
+import javax.crypto.ShortBufferException;
+import javax.crypto.spec.SecretKeySpec;
+
+/**
+ * Base class for {@link CipherSpi} implementations of Android KeyStore backed ciphers.
+ *
+ * @hide
+ */
+abstract class AndroidKeyStoreCipherSpiBase extends CipherSpi implements KeyStoreCryptoOperation {
+    private static final String TAG = "AndroidKeyStoreCipherSpiBase";
+
+    // Fields below are populated by Cipher.init and KeyStore.begin and should be preserved after
+    // doFinal finishes.
+    private boolean mEncrypting;
+    private int mKeymasterPurposeOverride = -1;
+    private AndroidKeyStoreKey mKey;
+    private SecureRandom mRng;
+
+    /**
+     * Object representing this operation inside keystore service. It is initialized
+     * by {@code engineInit} and is invalidated when {@code engineDoFinal} succeeds and on some
+     * error conditions in between.
+     */
+    private KeyStoreOperation mOperation;
+    /**
+     * The operation challenge is required when an operation needs user authorization.
+     * The challenge is subjected to an authenticator, e.g., Gatekeeper or a biometric
+     * authenticator, and included in the authentication token minted by this authenticator.
+     * It may be null, if the operation does not require authorization.
+     */
+    private long mOperationChallenge;
+    private KeyStoreCryptoOperationStreamer mMainDataStreamer;
+    private KeyStoreCryptoOperationStreamer mAdditionalAuthenticationDataStreamer;
+    private boolean mAdditionalAuthenticationDataStreamerClosed;
+
+    /**
+     * Encountered exception which could not be immediately thrown because it was encountered inside
+     * a method that does not throw checked exception. This exception will be thrown from
+     * {@code engineDoFinal}. Once such an exception is encountered, {@code engineUpdate} and
+     * {@code engineDoFinal} start ignoring input data.
+     */
+    private Exception mCachedException;
+
+    AndroidKeyStoreCipherSpiBase() {
+        mOperation = null;
+        mEncrypting = false;
+        mKeymasterPurposeOverride = -1;
+        mKey = null;
+        mRng = null;
+        mOperationChallenge = 0;
+        mMainDataStreamer = null;
+        mAdditionalAuthenticationDataStreamer = null;
+        mAdditionalAuthenticationDataStreamerClosed = false;
+        mCachedException = null;
+    }
+
+    @Override
+    protected final void engineInit(int opmode, Key key, SecureRandom random)
+            throws InvalidKeyException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            init(opmode, key, random);
+            initAlgorithmSpecificParameters();
+            try {
+                ensureKeystoreOperationInitialized();
+            } catch (InvalidAlgorithmParameterException e) {
+                throw new InvalidKeyException(e);
+            }
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    @Override
+    protected final void engineInit(int opmode, Key key, AlgorithmParameters params,
+            SecureRandom random) throws InvalidKeyException, InvalidAlgorithmParameterException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            init(opmode, key, random);
+            initAlgorithmSpecificParameters(params);
+            ensureKeystoreOperationInitialized();
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    @Override
+    protected final void engineInit(int opmode, Key key, AlgorithmParameterSpec params,
+            SecureRandom random) throws InvalidKeyException, InvalidAlgorithmParameterException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            init(opmode, key, random);
+            initAlgorithmSpecificParameters(params);
+            ensureKeystoreOperationInitialized();
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    private void init(int opmode, Key key, SecureRandom random) throws InvalidKeyException {
+        switch (opmode) {
+            case Cipher.ENCRYPT_MODE:
+            case Cipher.WRAP_MODE:
+                mEncrypting = true;
+                break;
+            case Cipher.DECRYPT_MODE:
+            case Cipher.UNWRAP_MODE:
+                mEncrypting = false;
+                break;
+            default:
+                throw new InvalidParameterException("Unsupported opmode: " + opmode);
+        }
+        initKey(opmode, key);
+        if (mKey == null) {
+            throw new ProviderException("initKey did not initialize the key");
+        }
+        mRng = random;
+    }
+
+    private void abortOperation() {
+        KeyStoreCryptoOperationUtils.abortOperation(mOperation);
+        mOperation = null;
+    }
+
+    /**
+     * Resets this cipher to its pristine pre-init state. This must be equivalent to obtaining a new
+     * cipher instance.
+     *
+     * <p>Subclasses storing additional state should override this method, reset the additional
+     * state, and then chain to superclass.
+     */
+    @CallSuper
+    protected void resetAll() {
+        abortOperation();
+        mEncrypting = false;
+        mKeymasterPurposeOverride = -1;
+        mKey = null;
+        mRng = null;
+        mOperationChallenge = 0;
+        mMainDataStreamer = null;
+        mAdditionalAuthenticationDataStreamer = null;
+        mAdditionalAuthenticationDataStreamerClosed = false;
+        mCachedException = null;
+    }
+
+    /**
+     * Resets this cipher while preserving the initialized state. This must be equivalent to
+     * rolling back the cipher's state to just after the most recent {@code engineInit} completed
+     * successfully.
+     *
+     * <p>Subclasses storing additional post-init state should override this method, reset the
+     * additional state, and then chain to superclass.
+     */
+    @CallSuper
+    protected void resetWhilePreservingInitState() {
+        abortOperation();
+        mOperationChallenge = 0;
+        mMainDataStreamer = null;
+        mAdditionalAuthenticationDataStreamer = null;
+        mAdditionalAuthenticationDataStreamerClosed = false;
+        mCachedException = null;
+    }
+
+    private void ensureKeystoreOperationInitialized() throws InvalidKeyException,
+            InvalidAlgorithmParameterException {
+        if (mMainDataStreamer != null) {
+            return;
+        }
+        if (mCachedException != null) {
+            return;
+        }
+        if (mKey == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+
+        List<KeyParameter> parameters = new ArrayList<>();
+        addAlgorithmSpecificParametersToBegin(parameters);
+
+        int purpose;
+        if (mKeymasterPurposeOverride != -1) {
+            purpose = mKeymasterPurposeOverride;
+        } else {
+            purpose = mEncrypting
+                    ? KeymasterDefs.KM_PURPOSE_ENCRYPT : KeymasterDefs.KM_PURPOSE_DECRYPT;
+        }
+
+        parameters.add(KeyStore2ParameterUtils.makeEnum(KeymasterDefs.KM_TAG_PURPOSE, purpose));
+
+        try {
+            mOperation = mKey.getSecurityLevel().createOperation(
+                    mKey.getKeyIdDescriptor(),
+                    parameters
+            );
+        } catch (KeyStoreException keyStoreException) {
+            GeneralSecurityException e = KeyStoreCryptoOperationUtils.getExceptionForCipherInit(
+                    mKey, keyStoreException);
+            if (e != null) {
+                if (e instanceof InvalidKeyException) {
+                    throw (InvalidKeyException) e;
+                } else if (e instanceof InvalidAlgorithmParameterException) {
+                    throw (InvalidAlgorithmParameterException) e;
+                } else {
+                    throw new ProviderException("Unexpected exception type", e);
+                }
+            }
+        }
+
+        // Now we check if we got an operation challenge. This indicates that user authorization
+        // is required. And if we got a challenge we check if the authorization can possibly
+        // succeed.
+        mOperationChallenge = KeyStoreCryptoOperationUtils.getOrMakeOperationChallenge(
+                mOperation, mKey);
+
+        loadAlgorithmSpecificParametersFromBeginResult(mOperation.getParameters());
+        mMainDataStreamer = createMainDataStreamer(mOperation);
+        mAdditionalAuthenticationDataStreamer =
+                createAdditionalAuthenticationDataStreamer(mOperation);
+        mAdditionalAuthenticationDataStreamerClosed = false;
+    }
+
+    /**
+     * Creates a streamer which sends plaintext/ciphertext into the provided KeyStore and receives
+     * the corresponding ciphertext/plaintext from the KeyStore.
+     *
+     * <p>This implementation returns a working streamer.
+     */
+    @NonNull
+    protected KeyStoreCryptoOperationStreamer createMainDataStreamer(
+            KeyStoreOperation operation) {
+        return new KeyStoreCryptoOperationChunkedStreamer(
+                new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(
+                        operation), 0);
+    }
+
+    /**
+     * Creates a streamer which sends Additional Authentication Data (AAD) into the KeyStore.
+     *
+     * <p>This implementation returns {@code null}.
+     *
+     * @return stream or {@code null} if AAD is not supported by this cipher.
+     */
+    @Nullable
+    protected KeyStoreCryptoOperationStreamer createAdditionalAuthenticationDataStreamer(
+            @SuppressWarnings("unused") KeyStoreOperation operation) {
+        return null;
+    }
+
+    @Override
+    protected final byte[] engineUpdate(byte[] input, int inputOffset, int inputLen) {
+        if (mCachedException != null) {
+            return null;
+        }
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException | InvalidAlgorithmParameterException e) {
+            mCachedException = e;
+            return null;
+        }
+
+        if (inputLen == 0) {
+            return null;
+        }
+
+        byte[] output;
+        try {
+            flushAAD();
+            output = mMainDataStreamer.update(input, inputOffset, inputLen);
+        } catch (KeyStoreException e) {
+            mCachedException = e;
+            return null;
+        }
+
+        if (output.length == 0) {
+            return null;
+        }
+
+        return output;
+    }
+
+    private void flushAAD() throws KeyStoreException {
+        if ((mAdditionalAuthenticationDataStreamer != null)
+                && (!mAdditionalAuthenticationDataStreamerClosed)) {
+            byte[] output;
+            try {
+                output = mAdditionalAuthenticationDataStreamer.doFinal(
+                        EmptyArray.BYTE, 0, 0,
+                        null); // no signature
+            } finally {
+                mAdditionalAuthenticationDataStreamerClosed = true;
+            }
+            if ((output != null) && (output.length > 0)) {
+                throw new ProviderException(
+                        "AAD update unexpectedly returned data: " + output.length + " bytes");
+            }
+        }
+    }
+
+    @Override
+    protected final int engineUpdate(byte[] input, int inputOffset, int inputLen, byte[] output,
+            int outputOffset) throws ShortBufferException {
+        byte[] outputCopy = engineUpdate(input, inputOffset, inputLen);
+        if (outputCopy == null) {
+            return 0;
+        }
+        int outputAvailable = output.length - outputOffset;
+        if (outputCopy.length > outputAvailable) {
+            throw new ShortBufferException("Output buffer too short. Produced: "
+                    + outputCopy.length + ", available: " + outputAvailable);
+        }
+        System.arraycopy(outputCopy, 0, output, outputOffset, outputCopy.length);
+        return outputCopy.length;
+    }
+
+    @Override
+    protected final int engineUpdate(ByteBuffer input, ByteBuffer output)
+            throws ShortBufferException {
+        if (input == null) {
+            throw new NullPointerException("input == null");
+        }
+        if (output == null) {
+            throw new NullPointerException("output == null");
+        }
+
+        int inputSize = input.remaining();
+        byte[] outputArray;
+        if (input.hasArray()) {
+            outputArray =
+                    engineUpdate(
+                            input.array(), input.arrayOffset() + input.position(), inputSize);
+            input.position(input.position() + inputSize);
+        } else {
+            byte[] inputArray = new byte[inputSize];
+            input.get(inputArray);
+            outputArray = engineUpdate(inputArray, 0, inputSize);
+        }
+
+        int outputSize = (outputArray != null) ? outputArray.length : 0;
+        if (outputSize > 0) {
+            int outputBufferAvailable = output.remaining();
+            try {
+                output.put(outputArray);
+            } catch (BufferOverflowException e) {
+                throw new ShortBufferException(
+                        "Output buffer too small. Produced: " + outputSize + ", available: "
+                                + outputBufferAvailable);
+            }
+        }
+        return outputSize;
+    }
+
+    @Override
+    protected final void engineUpdateAAD(byte[] input, int inputOffset, int inputLen) {
+        if (mCachedException != null) {
+            return;
+        }
+
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException | InvalidAlgorithmParameterException e) {
+            mCachedException = e;
+            return;
+        }
+
+        if (mAdditionalAuthenticationDataStreamerClosed) {
+            throw new IllegalStateException(
+                    "AAD can only be provided before Cipher.update is invoked");
+        }
+
+        if (mAdditionalAuthenticationDataStreamer == null) {
+            throw new IllegalStateException("This cipher does not support AAD");
+        }
+
+        byte[] output;
+        try {
+            output = mAdditionalAuthenticationDataStreamer.update(input, inputOffset, inputLen);
+        } catch (KeyStoreException e) {
+            mCachedException = e;
+            return;
+        }
+
+        if ((output != null) && (output.length > 0)) {
+            throw new ProviderException("AAD update unexpectedly produced output: "
+                    + output.length + " bytes");
+        }
+    }
+
+    @Override
+    protected final void engineUpdateAAD(ByteBuffer src) {
+        if (src == null) {
+            throw new IllegalArgumentException("src == null");
+        }
+        if (!src.hasRemaining()) {
+            return;
+        }
+
+        byte[] input;
+        int inputOffset;
+        int inputLen;
+        if (src.hasArray()) {
+            input = src.array();
+            inputOffset = src.arrayOffset() + src.position();
+            inputLen = src.remaining();
+            src.position(src.limit());
+        } else {
+            input = new byte[src.remaining()];
+            inputOffset = 0;
+            inputLen = input.length;
+            src.get(input);
+        }
+        engineUpdateAAD(input, inputOffset, inputLen);
+    }
+
+    @Override
+    protected final byte[] engineDoFinal(byte[] input, int inputOffset, int inputLen)
+            throws IllegalBlockSizeException, BadPaddingException {
+        if (mCachedException != null) {
+            throw (IllegalBlockSizeException)
+                    new IllegalBlockSizeException().initCause(mCachedException);
+        }
+
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException | InvalidAlgorithmParameterException e) {
+            throw (IllegalBlockSizeException) new IllegalBlockSizeException().initCause(e);
+        }
+
+        byte[] output;
+        try {
+            flushAAD();
+            output = mMainDataStreamer.doFinal(
+                    input, inputOffset, inputLen,
+                    null); // no signature involved
+        } catch (KeyStoreException e) {
+            switch (e.getErrorCode()) {
+                case KeymasterDefs.KM_ERROR_INVALID_ARGUMENT:
+                    throw (BadPaddingException) new BadPaddingException().initCause(e);
+                case KeymasterDefs.KM_ERROR_VERIFICATION_FAILED:
+                    throw (AEADBadTagException) new AEADBadTagException().initCause(e);
+                default:
+                    throw (IllegalBlockSizeException) new IllegalBlockSizeException().initCause(e);
+            }
+        }
+
+        resetWhilePreservingInitState();
+        return output;
+    }
+
+    @Override
+    protected final int engineDoFinal(byte[] input, int inputOffset, int inputLen, byte[] output,
+            int outputOffset) throws ShortBufferException, IllegalBlockSizeException,
+            BadPaddingException {
+        byte[] outputCopy = engineDoFinal(input, inputOffset, inputLen);
+        if (outputCopy == null) {
+            return 0;
+        }
+        int outputAvailable = output.length - outputOffset;
+        if (outputCopy.length > outputAvailable) {
+            throw new ShortBufferException("Output buffer too short. Produced: "
+                    + outputCopy.length + ", available: " + outputAvailable);
+        }
+        System.arraycopy(outputCopy, 0, output, outputOffset, outputCopy.length);
+        return outputCopy.length;
+    }
+
+    @Override
+    protected final int engineDoFinal(ByteBuffer input, ByteBuffer output)
+            throws ShortBufferException, IllegalBlockSizeException, BadPaddingException {
+        if (input == null) {
+            throw new NullPointerException("input == null");
+        }
+        if (output == null) {
+            throw new NullPointerException("output == null");
+        }
+
+        int inputSize = input.remaining();
+        byte[] outputArray;
+        if (input.hasArray()) {
+            outputArray =
+                    engineDoFinal(
+                            input.array(), input.arrayOffset() + input.position(), inputSize);
+            input.position(input.position() + inputSize);
+        } else {
+            byte[] inputArray = new byte[inputSize];
+            input.get(inputArray);
+            outputArray = engineDoFinal(inputArray, 0, inputSize);
+        }
+
+        int outputSize = (outputArray != null) ? outputArray.length : 0;
+        if (outputSize > 0) {
+            int outputBufferAvailable = output.remaining();
+            try {
+                output.put(outputArray);
+            } catch (BufferOverflowException e) {
+                throw new ShortBufferException(
+                        "Output buffer too small. Produced: " + outputSize + ", available: "
+                                + outputBufferAvailable);
+            }
+        }
+        return outputSize;
+    }
+
+    @Override
+    protected final byte[] engineWrap(Key key)
+            throws IllegalBlockSizeException, InvalidKeyException {
+        if (mKey == null) {
+            throw new IllegalStateException("Not initilized");
+        }
+
+        if (!isEncrypting()) {
+            throw new IllegalStateException(
+                    "Cipher must be initialized in Cipher.WRAP_MODE to wrap keys");
+        }
+
+        if (key == null) {
+            throw new NullPointerException("key == null");
+        }
+        byte[] encoded = null;
+        if (key instanceof SecretKey) {
+            if ("RAW".equalsIgnoreCase(key.getFormat())) {
+                encoded = key.getEncoded();
+            }
+            if (encoded == null) {
+                try {
+                    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(key.getAlgorithm());
+                    SecretKeySpec spec =
+                            (SecretKeySpec) keyFactory.getKeySpec(
+                                    (SecretKey) key, SecretKeySpec.class);
+                    encoded = spec.getEncoded();
+                } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
+                    throw new InvalidKeyException(
+                            "Failed to wrap key because it does not export its key material",
+                            e);
+                }
+            }
+        } else if (key instanceof PrivateKey) {
+            if ("PKCS8".equalsIgnoreCase(key.getFormat())) {
+                encoded = key.getEncoded();
+            }
+            if (encoded == null) {
+                try {
+                    KeyFactory keyFactory = KeyFactory.getInstance(key.getAlgorithm());
+                    PKCS8EncodedKeySpec spec =
+                            keyFactory.getKeySpec(key, PKCS8EncodedKeySpec.class);
+                    encoded = spec.getEncoded();
+                } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
+                    throw new InvalidKeyException(
+                            "Failed to wrap key because it does not export its key material",
+                            e);
+                }
+            }
+        } else if (key instanceof PublicKey) {
+            if ("X.509".equalsIgnoreCase(key.getFormat())) {
+                encoded = key.getEncoded();
+            }
+            if (encoded == null) {
+                try {
+                    KeyFactory keyFactory = KeyFactory.getInstance(key.getAlgorithm());
+                    X509EncodedKeySpec spec =
+                            keyFactory.getKeySpec(key, X509EncodedKeySpec.class);
+                    encoded = spec.getEncoded();
+                } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
+                    throw new InvalidKeyException(
+                            "Failed to wrap key because it does not export its key material",
+                            e);
+                }
+            }
+        } else {
+            throw new InvalidKeyException("Unsupported key type: " + key.getClass().getName());
+        }
+
+        if (encoded == null) {
+            throw new InvalidKeyException(
+                    "Failed to wrap key because it does not export its key material");
+        }
+
+        try {
+            return engineDoFinal(encoded, 0, encoded.length);
+        } catch (BadPaddingException e) {
+            throw (IllegalBlockSizeException) new IllegalBlockSizeException().initCause(e);
+        }
+    }
+
+    @Override
+    protected final Key engineUnwrap(byte[] wrappedKey, String wrappedKeyAlgorithm,
+            int wrappedKeyType) throws InvalidKeyException, NoSuchAlgorithmException {
+        if (mKey == null) {
+            throw new IllegalStateException("Not initilized");
+        }
+
+        if (isEncrypting()) {
+            throw new IllegalStateException(
+                    "Cipher must be initialized in Cipher.WRAP_MODE to wrap keys");
+        }
+
+        if (wrappedKey == null) {
+            throw new NullPointerException("wrappedKey == null");
+        }
+
+        byte[] encoded;
+        try {
+            encoded = engineDoFinal(wrappedKey, 0, wrappedKey.length);
+        } catch (IllegalBlockSizeException | BadPaddingException e) {
+            throw new InvalidKeyException("Failed to unwrap key", e);
+        }
+
+        switch (wrappedKeyType) {
+            case Cipher.SECRET_KEY:
+            {
+                return new SecretKeySpec(encoded, wrappedKeyAlgorithm);
+                // break;
+            }
+            case Cipher.PRIVATE_KEY:
+            {
+                KeyFactory keyFactory = KeyFactory.getInstance(wrappedKeyAlgorithm);
+                try {
+                    return keyFactory.generatePrivate(new PKCS8EncodedKeySpec(encoded));
+                } catch (InvalidKeySpecException e) {
+                    throw new InvalidKeyException(
+                            "Failed to create private key from its PKCS#8 encoded form", e);
+                }
+                // break;
+            }
+            case Cipher.PUBLIC_KEY:
+            {
+                KeyFactory keyFactory = KeyFactory.getInstance(wrappedKeyAlgorithm);
+                try {
+                    return keyFactory.generatePublic(new X509EncodedKeySpec(encoded));
+                } catch (InvalidKeySpecException e) {
+                    throw new InvalidKeyException(
+                            "Failed to create public key from its X.509 encoded form", e);
+                }
+                // break;
+            }
+            default:
+                throw new InvalidParameterException(
+                        "Unsupported wrappedKeyType: " + wrappedKeyType);
+        }
+    }
+
+    @Override
+    protected final void engineSetMode(String mode) throws NoSuchAlgorithmException {
+        // This should never be invoked because all algorithms registered with the AndroidKeyStore
+        // provide explicitly specify block mode.
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    protected final void engineSetPadding(String arg0) throws NoSuchPaddingException {
+        // This should never be invoked because all algorithms registered with the AndroidKeyStore
+        // provide explicitly specify padding mode.
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    protected final int engineGetKeySize(Key key) throws InvalidKeyException {
+        throw new UnsupportedOperationException();
+    }
+
+    @CallSuper
+    @Override
+    public void finalize() throws Throwable {
+        try {
+            abortOperation();
+        } finally {
+            super.finalize();
+        }
+    }
+
+    @Override
+    public final long getOperationHandle() {
+        return mOperationChallenge;
+    }
+
+    protected final void setKey(@NonNull AndroidKeyStoreKey key) {
+        mKey = key;
+    }
+
+    /**
+     * Overrides the default purpose/type of the crypto operation.
+     */
+    protected final void setKeymasterPurposeOverride(int keymasterPurpose) {
+        mKeymasterPurposeOverride = keymasterPurpose;
+    }
+
+    protected final int getKeymasterPurposeOverride() {
+        return mKeymasterPurposeOverride;
+    }
+
+    /**
+     * Returns {@code true} if this cipher is initialized for encryption, {@code false} if this
+     * cipher is initialized for decryption.
+     */
+    protected final boolean isEncrypting() {
+        return mEncrypting;
+    }
+
+    protected final long getConsumedInputSizeBytes() {
+        if (mMainDataStreamer == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+        return mMainDataStreamer.getConsumedInputSizeBytes();
+    }
+
+    protected final long getProducedOutputSizeBytes() {
+        if (mMainDataStreamer == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+        return mMainDataStreamer.getProducedOutputSizeBytes();
+    }
+
+    static String opmodeToString(int opmode) {
+        switch (opmode) {
+            case Cipher.ENCRYPT_MODE:
+                return "ENCRYPT_MODE";
+            case Cipher.DECRYPT_MODE:
+                return "DECRYPT_MODE";
+            case Cipher.WRAP_MODE:
+                return "WRAP_MODE";
+            case Cipher.UNWRAP_MODE:
+                return "UNWRAP_MODE";
+            default:
+                return String.valueOf(opmode);
+        }
+    }
+
+    // The methods below need to be implemented by subclasses.
+
+    /**
+     * Initializes this cipher with the provided key.
+     *
+     * @throws InvalidKeyException if the {@code key} is not suitable for this cipher in the
+     *         specified {@code opmode}.
+     *
+     * @see #setKey(AndroidKeyStoreKey)
+     */
+    protected abstract void initKey(int opmode, @Nullable Key key) throws InvalidKeyException;
+
+    /**
+     * Returns algorithm-specific parameters used by this cipher or {@code null} if no
+     * algorithm-specific parameters are used.
+     */
+    @Nullable
+    @Override
+    protected abstract AlgorithmParameters engineGetParameters();
+
+    /**
+     * Invoked by {@code engineInit} to initialize algorithm-specific parameters when no additional
+     * initialization parameters were provided.
+     *
+     * @throws InvalidKeyException if this cipher cannot be configured based purely on the provided
+     *         key and needs additional parameters to be provided to {@code Cipher.init}.
+     */
+    protected abstract void initAlgorithmSpecificParameters() throws InvalidKeyException;
+
+    /**
+     * Invoked by {@code engineInit} to initialize algorithm-specific parameters when additional
+     * parameters were provided.
+     *
+     * @param params additional algorithm parameters or {@code null} if not specified.
+     *
+     * @throws InvalidAlgorithmParameterException if there is insufficient information to configure
+     *         this cipher or if the provided parameters are not suitable for this cipher.
+     */
+    protected abstract void initAlgorithmSpecificParameters(
+            @Nullable AlgorithmParameterSpec params) throws InvalidAlgorithmParameterException;
+
+    /**
+     * Invoked by {@code engineInit} to initialize algorithm-specific parameters when additional
+     * parameters were provided.
+     *
+     * @param params additional algorithm parameters or {@code null} if not specified.
+     *
+     * @throws InvalidAlgorithmParameterException if there is insufficient information to configure
+     *         this cipher or if the provided parameters are not suitable for this cipher.
+     */
+    protected abstract void initAlgorithmSpecificParameters(@Nullable AlgorithmParameters params)
+            throws InvalidAlgorithmParameterException;
+
+    /**
+     * Returns the amount of additional entropy (in bytes) to be provided to the KeyStore's
+     * {@code begin} operation. This amount of entropy is typically what's consumed to generate
+     * random parameters, such as IV.
+     *
+     * <p>For decryption, the return value should be {@code 0} because decryption should not be
+     * consuming any entropy. For encryption, the value combined with
+     * {@link #getAdditionalEntropyAmountForFinish()} should match (or exceed) the amount of Shannon
+     * entropy of the ciphertext produced by this cipher assuming the key, the plaintext, and all
+     * explicitly provided parameters to {@code Cipher.init} are known. For example, for AES CBC
+     * encryption with an explicitly provided IV the return value should be {@code 0}, whereas for
+     * the case where IV is generated by the KeyStore's {@code begin} operation it should be
+     * {@code 16}.
+     */
+    protected abstract int getAdditionalEntropyAmountForBegin();
+
+    /**
+     * Returns the amount of additional entropy (in bytes) to be provided to the KeyStore's
+     * {@code finish} operation. This amount of entropy is typically what's consumed by encryption
+     * padding scheme.
+     *
+     * <p>For decryption, the return value should be {@code 0} because decryption should not be
+     * consuming any entropy. For encryption, the value combined with
+     * {@link #getAdditionalEntropyAmountForBegin()} should match (or exceed) the amount of Shannon
+     * entropy of the ciphertext produced by this cipher assuming the key, the plaintext, and all
+     * explicitly provided parameters to {@code Cipher.init} are known. For example, for RSA with
+     * OAEP the return value should be the size of the OAEP hash output. For RSA with PKCS#1 padding
+     * the return value should be the size of the padding string or could be raised (for simplicity)
+     * to the size of the modulus.
+     */
+    protected abstract int getAdditionalEntropyAmountForFinish();
+
+    /**
+     * Invoked to add algorithm-specific parameters for the KeyStore's {@code begin} operation.
+     *
+     * @param parameters keystore/keymaster arguments to be populated with algorithm-specific
+     *        parameters.
+     */
+    protected abstract void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters);
+
+    /**
+     * Invoked to obtain algorithm-specific parameters from the result of the KeyStore's
+     * {@code begin} operation.
+     *
+     * <p>Some parameters, such as IV, are not required to be provided to {@code Cipher.init}. Such
+     * parameters, if not provided, must be generated by KeyStore and returned to the user of
+     * {@code Cipher} and potentially reused after {@code doFinal}.
+     *
+     * @param parameters keystore/keymaster arguments returned by KeyStore {@code createOperation}.
+     */
+    protected abstract void loadAlgorithmSpecificParametersFromBeginResult(
+            KeyParameter[] parameters);
+}

keystore/java/android/security/keystore2/AndroidKeyStoreECDSASignatureSpi.java

@@ -0,0 +1,207 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.KeyParameter;
+
+import libcore.util.EmptyArray;
+
+import java.io.ByteArrayOutputStream;
+import java.security.InvalidKeyException;
+import java.security.SignatureSpi;
+import java.util.List;
+
+/**
+ * Base class for {@link SignatureSpi} providing Android KeyStore backed ECDSA signatures.
+ *
+ * @hide
+ */
+abstract class AndroidKeyStoreECDSASignatureSpi extends AndroidKeyStoreSignatureSpiBase {
+
+    public final static class NONE extends AndroidKeyStoreECDSASignatureSpi {
+        public NONE() {
+            super(KeymasterDefs.KM_DIGEST_NONE);
+        }
+
+        @Override
+        protected KeyStoreCryptoOperationStreamer createMainDataStreamer(
+                KeyStoreOperation operation) {
+            return new TruncateToFieldSizeMessageStreamer(
+                    super.createMainDataStreamer(operation),
+                    getGroupSizeBits());
+        }
+
+        /**
+         * Streamer which buffers all input, then truncates it to field size, and then sends it into
+         * KeyStore via the provided delegate streamer.
+         */
+        private static class TruncateToFieldSizeMessageStreamer
+                implements KeyStoreCryptoOperationStreamer {
+
+            private final KeyStoreCryptoOperationStreamer mDelegate;
+            private final int mGroupSizeBits;
+            private final ByteArrayOutputStream mInputBuffer = new ByteArrayOutputStream();
+            private long mConsumedInputSizeBytes;
+
+            private TruncateToFieldSizeMessageStreamer(
+                    KeyStoreCryptoOperationStreamer delegate,
+                    int groupSizeBits) {
+                mDelegate = delegate;
+                mGroupSizeBits = groupSizeBits;
+            }
+
+            @Override
+            public byte[] update(byte[] input, int inputOffset, int inputLength)
+                    throws KeyStoreException {
+                if (inputLength > 0) {
+                    mInputBuffer.write(input, inputOffset, inputLength);
+                    mConsumedInputSizeBytes += inputLength;
+                }
+                return EmptyArray.BYTE;
+            }
+
+            @Override
+            public byte[] doFinal(byte[] input, int inputOffset, int inputLength, byte[] signature)
+                    throws KeyStoreException {
+                if (inputLength > 0) {
+                    mConsumedInputSizeBytes += inputLength;
+                    mInputBuffer.write(input, inputOffset, inputLength);
+                }
+
+                byte[] bufferedInput = mInputBuffer.toByteArray();
+                mInputBuffer.reset();
+                // Truncate input at field size (bytes)
+                return mDelegate.doFinal(bufferedInput,
+                        0,
+                        Math.min(bufferedInput.length, ((mGroupSizeBits + 7) / 8)),
+                        signature);
+            }
+
+            @Override
+            public long getConsumedInputSizeBytes() {
+                return mConsumedInputSizeBytes;
+            }
+
+            @Override
+            public long getProducedOutputSizeBytes() {
+                return mDelegate.getProducedOutputSizeBytes();
+            }
+        }
+    }
+
+    public final static class SHA1 extends AndroidKeyStoreECDSASignatureSpi {
+        public SHA1() {
+            super(KeymasterDefs.KM_DIGEST_SHA1);
+        }
+    }
+
+    public final static class SHA224 extends AndroidKeyStoreECDSASignatureSpi {
+        public SHA224() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_224);
+        }
+    }
+
+    public final static class SHA256 extends AndroidKeyStoreECDSASignatureSpi {
+        public SHA256() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_256);
+        }
+    }
+
+    public final static class SHA384 extends AndroidKeyStoreECDSASignatureSpi {
+        public SHA384() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_384);
+        }
+    }
+
+    public final static class SHA512 extends AndroidKeyStoreECDSASignatureSpi {
+        public SHA512() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_512);
+        }
+    }
+
+    private final int mKeymasterDigest;
+
+    private int mGroupSizeBits = -1;
+
+    AndroidKeyStoreECDSASignatureSpi(int keymasterDigest) {
+        mKeymasterDigest = keymasterDigest;
+    }
+
+    @Override
+    protected final void initKey(AndroidKeyStoreKey key) throws InvalidKeyException {
+        if (!KeyProperties.KEY_ALGORITHM_EC.equalsIgnoreCase(key.getAlgorithm())) {
+            throw new InvalidKeyException("Unsupported key algorithm: " + key.getAlgorithm()
+                    + ". Only" + KeyProperties.KEY_ALGORITHM_EC + " supported");
+        }
+
+        long keySizeBits = -1;
+        for (Authorization a : key.getAuthorizations()) {
+            if (a.keyParameter.tag == KeymasterDefs.KM_TAG_KEY_SIZE) {
+                keySizeBits = KeyStore2ParameterUtils.getUnsignedInt(a);
+            }
+        }
+
+        if (keySizeBits == -1) {
+            throw new InvalidKeyException("Size of key not known");
+        } else if (keySizeBits > Integer.MAX_VALUE) {
+            throw new InvalidKeyException("Key too large: " + keySizeBits + " bits");
+        }
+        mGroupSizeBits = (int) keySizeBits;
+
+        super.initKey(key);
+    }
+
+    @Override
+    protected final void resetAll() {
+        mGroupSizeBits = -1;
+        super.resetAll();
+    }
+
+    @Override
+    protected final void resetWhilePreservingInitState() {
+        super.resetWhilePreservingInitState();
+    }
+
+    @Override
+    protected final void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters) {
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, KeymasterDefs.KM_ALGORITHM_EC
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_DIGEST, mKeymasterDigest
+        ));
+    }
+
+    @Override
+    protected final int getAdditionalEntropyAmountForSign() {
+        return (mGroupSizeBits + 7) / 8;
+    }
+
+    protected final int getGroupSizeBits() {
+        if (mGroupSizeBits == -1) {
+            throw new IllegalStateException("Not initialized");
+        }
+        return mGroupSizeBits;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreECPrivateKey.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.KeyDescriptor;
+
+import java.security.PrivateKey;
+import java.security.interfaces.ECKey;
+import java.security.spec.ECParameterSpec;
+
+/**
+ * EC private key (instance of {@link PrivateKey} and {@link ECKey}) backed by keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreECPrivateKey extends AndroidKeyStorePrivateKey implements ECKey {
+    private final ECParameterSpec mParams;
+
+    public AndroidKeyStoreECPrivateKey(@NonNull KeyDescriptor descriptor,
+            long keyId,
+            Authorization[] authorizations,
+            @NonNull KeyStoreSecurityLevel securityLevel,
+            @NonNull ECParameterSpec params) {
+        super(descriptor, keyId, authorizations, KeyProperties.KEY_ALGORITHM_EC, securityLevel);
+        mParams = params;
+    }
+
+    @Override
+    public ECParameterSpec getParams() {
+        return mParams;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreECPublicKey.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+
+import java.security.interfaces.ECPublicKey;
+import java.security.spec.ECParameterSpec;
+import java.security.spec.ECPoint;
+
+/**
+ * {@link ECPublicKey} backed by keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreECPublicKey extends AndroidKeyStorePublicKey implements ECPublicKey {
+
+    private final ECParameterSpec mParams;
+    private final ECPoint mW;
+
+    public AndroidKeyStoreECPublicKey(@NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata,
+            @NonNull KeyStoreSecurityLevel securityLevel,
+            @NonNull ECParameterSpec params, @NonNull ECPoint w) {
+        super(descriptor, metadata, KeyProperties.KEY_ALGORITHM_EC, securityLevel);
+        mParams = params;
+        mW = w;
+    }
+
+    public AndroidKeyStoreECPublicKey(@NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata,
+            @NonNull KeyStoreSecurityLevel securityLevel, @NonNull ECPublicKey info) {
+        this(descriptor, metadata, securityLevel, info.getParams(), info.getW());
+        if (!"X.509".equalsIgnoreCase(info.getFormat())) {
+            throw new IllegalArgumentException(
+                    "Unsupported key export format: " + info.getFormat());
+        }
+    }
+
+    @Override
+    public AndroidKeyStorePrivateKey getPrivateKey() {
+        return new AndroidKeyStoreECPrivateKey(
+                getUserKeyDescriptor(), getKeyIdDescriptor().nspace, getAuthorizations(),
+                getSecurityLevel(), mParams);
+    }
+
+    @Override
+    public ECParameterSpec getParams() {
+        return mParams;
+    }
+
+    @Override
+    public ECPoint getW() {
+        return mW;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreHmacSpi.java

@@ -0,0 +1,259 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyStoreCryptoOperation;
+import android.security.keystore.KeymasterUtils;
+import android.system.keystore2.KeyParameter;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.Key;
+import java.security.ProviderException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.crypto.MacSpi;
+
+/**
+ * {@link MacSpi} which provides HMAC implementations backed by Android KeyStore.
+ *
+ * @hide
+ */
+public abstract class AndroidKeyStoreHmacSpi extends MacSpi implements KeyStoreCryptoOperation {
+
+    private static final String TAG = "AndroidKeyStoreHmacSpi";
+
+    public static class HmacSHA1 extends AndroidKeyStoreHmacSpi {
+        public HmacSHA1() {
+            super(KeymasterDefs.KM_DIGEST_SHA1);
+        }
+    }
+
+    public static class HmacSHA224 extends AndroidKeyStoreHmacSpi {
+        public HmacSHA224() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_224);
+        }
+    }
+
+    public static class HmacSHA256 extends AndroidKeyStoreHmacSpi {
+        public HmacSHA256() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_256);
+        }
+    }
+
+    public static class HmacSHA384 extends AndroidKeyStoreHmacSpi {
+        public HmacSHA384() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_384);
+        }
+    }
+
+    public static class HmacSHA512 extends AndroidKeyStoreHmacSpi {
+        public HmacSHA512() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_512);
+        }
+    }
+
+    private final int mKeymasterDigest;
+    private final int mMacSizeBits;
+
+    // Fields below are populated by engineInit and should be preserved after engineDoFinal.
+    private AndroidKeyStoreSecretKey mKey;
+
+    // Fields below are reset when engineDoFinal succeeds.
+    private KeyStoreCryptoOperationChunkedStreamer mChunkedStreamer;
+    private KeyStoreOperation mOperation;
+    private long mOperationChallenge;
+
+    protected AndroidKeyStoreHmacSpi(int keymasterDigest) {
+        mKeymasterDigest = keymasterDigest;
+        mMacSizeBits = KeymasterUtils.getDigestOutputSizeBits(keymasterDigest);
+        mOperation = null;
+        mOperationChallenge = 0;
+        mKey = null;
+        mChunkedStreamer = null;
+    }
+
+    @Override
+    protected int engineGetMacLength() {
+        return (mMacSizeBits + 7) / 8;
+    }
+
+    @Override
+    protected void engineInit(Key key, AlgorithmParameterSpec params) throws InvalidKeyException,
+            InvalidAlgorithmParameterException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            init(key, params);
+            ensureKeystoreOperationInitialized();
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    private void init(Key key, AlgorithmParameterSpec params) throws InvalidKeyException,
+        InvalidAlgorithmParameterException {
+        if (key == null) {
+            throw new InvalidKeyException("key == null");
+        } else if (!(key instanceof AndroidKeyStoreSecretKey)) {
+            throw new InvalidKeyException(
+                    "Only Android KeyStore secret keys supported. Key: " + key);
+        }
+        mKey = (AndroidKeyStoreSecretKey) key;
+
+        if (params != null) {
+            throw new InvalidAlgorithmParameterException(
+                    "Unsupported algorithm parameters: " + params);
+        }
+
+    }
+
+    private void abortOperation() {
+        KeyStoreCryptoOperationUtils.abortOperation(mOperation);
+        mOperation = null;
+    }
+
+    private void resetAll() {
+        abortOperation();
+        mOperationChallenge = 0;
+        mKey = null;
+        mChunkedStreamer = null;
+    }
+
+    private void resetWhilePreservingInitState() {
+        abortOperation();
+        mOperationChallenge = 0;
+        mChunkedStreamer = null;
+    }
+
+    @Override
+    protected void engineReset() {
+        resetWhilePreservingInitState();
+    }
+
+    private void ensureKeystoreOperationInitialized() throws InvalidKeyException {
+        if (mChunkedStreamer != null) {
+            return;
+        }
+        if (mKey == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+
+        List<KeyParameter> parameters = new ArrayList<>();
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, KeymasterDefs.KM_ALGORITHM_HMAC
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_DIGEST, mKeymasterDigest
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeInt(
+                KeymasterDefs.KM_TAG_MAC_LENGTH, mMacSizeBits
+        ));
+
+        try {
+            mOperation = mKey.getSecurityLevel().createOperation(
+                    mKey.getKeyIdDescriptor(),
+                    parameters
+            );
+        } catch (KeyStoreException keyStoreException) {
+            // If necessary, throw an exception due to KeyStore operation having failed.
+            InvalidKeyException e = KeyStoreCryptoOperationUtils.getInvalidKeyException(
+                    mKey, keyStoreException);
+            if (e != null) {
+                throw e;
+            }
+        }
+
+        // Now we check if we got an operation challenge. This indicates that user authorization
+        // is required. And if we got a challenge we check if the authorization can possibly
+        // succeed.
+        mOperationChallenge = KeyStoreCryptoOperationUtils.getOrMakeOperationChallenge(
+                mOperation, mKey);
+
+        mChunkedStreamer = new KeyStoreCryptoOperationChunkedStreamer(
+                new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(
+                        mOperation));
+    }
+
+    @Override
+    protected void engineUpdate(byte input) {
+        engineUpdate(new byte[] {input}, 0, 1);
+    }
+
+    @Override
+    protected void engineUpdate(byte[] input, int offset, int len) {
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException e) {
+            throw new ProviderException("Failed to reinitialize MAC", e);
+        }
+
+        byte[] output;
+        try {
+            output = mChunkedStreamer.update(input, offset, len);
+        } catch (KeyStoreException e) {
+            throw new ProviderException("Keystore operation failed", e);
+        }
+        if ((output != null) && (output.length != 0)) {
+            throw new ProviderException("Update operation unexpectedly produced output");
+        }
+    }
+
+    @Override
+    protected byte[] engineDoFinal() {
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException e) {
+            throw new ProviderException("Failed to reinitialize MAC", e);
+        }
+
+        byte[] result;
+        try {
+            result = mChunkedStreamer.doFinal(
+                    null, 0, 0,
+                    null); // no signature provided -- this invocation will generate one
+        } catch (KeyStoreException e) {
+            throw new ProviderException("Keystore operation failed", e);
+        }
+
+        resetWhilePreservingInitState();
+        return result;
+    }
+
+    @Override
+    public void finalize() throws Throwable {
+        try {
+            abortOperation();
+        } finally {
+            super.finalize();
+        }
+    }
+
+    @Override
+    public long getOperationHandle() {
+        return mOperationChallenge;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreKey.java

@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.Domain;
+import android.system.keystore2.KeyDescriptor;
+import android.util.Log;
+
+import java.security.Key;
+
+/**
+ * {@link Key} backed by Android Keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreKey implements Key {
+    // This is the original KeyDescriptor by which the key was loaded from
+    // with alias and domain.
+    private final KeyDescriptor mDescriptor;
+    // The key id can be used make certain manipulations to the keystore database
+    // assuring that the manipulation is made to the exact key that was loaded
+    // from the database. Alias based manipulations can not assure this, because
+    // aliases can be rebound to other keys at any time.
+    private final long mKeyId;
+    private final Authorization[] mAuthorizations;
+    // TODO extract algorithm string from metadata.
+    private final String mAlgorithm;
+
+    // This is the security level interface, that this key is associated with.
+    // We do not include this member in comparisons.
+    private final KeyStoreSecurityLevel mSecurityLevel;
+
+    AndroidKeyStoreKey(@NonNull KeyDescriptor descriptor,
+            long keyId,
+            @NonNull Authorization[] authorizations,
+            @NonNull String algorithm,
+            @NonNull KeyStoreSecurityLevel securityLevel) {
+        mDescriptor = descriptor;
+        mKeyId = keyId;
+        mAuthorizations = authorizations;
+        mAlgorithm = algorithm;
+        mSecurityLevel = securityLevel;
+    }
+
+    KeyDescriptor getUserKeyDescriptor() {
+        return mDescriptor;
+    }
+
+    KeyDescriptor getKeyIdDescriptor() {
+        KeyDescriptor descriptor = new KeyDescriptor();
+        descriptor.nspace = mKeyId;
+        descriptor.domain = Domain.KEY_ID;
+        descriptor.alias = null;
+        descriptor.blob = null;
+        return descriptor;
+    }
+
+    Authorization[] getAuthorizations() {
+        return mAuthorizations;
+    }
+
+    KeyStoreSecurityLevel getSecurityLevel() {
+        return mSecurityLevel;
+    }
+
+
+    @Override
+    public String getAlgorithm() {
+        return mAlgorithm;
+    }
+
+    @Override
+    public String getFormat() {
+        // This key does not export its key material
+        return null;
+    }
+
+    @Override
+    public byte[] getEncoded() {
+        // This key does not export its key material
+        return null;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+
+        result = prime * result + ((mDescriptor == null) ? 0 : mDescriptor.hashCode());
+        result = prime * result + (int) (mKeyId >>> 32);
+        result = prime * result + (int) (mKeyId & 0xffffffff);
+        result = prime * result + ((mAuthorizations == null) ? 0 : mAuthorizations.hashCode());
+        result = prime * result + ((mAlgorithm == null) ? 0 : mAlgorithm.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        AndroidKeyStoreKey other = (AndroidKeyStoreKey) obj;
+        if (mKeyId != other.mKeyId) {
+            return false;
+        }
+
+        // If the key ids are equal and the class matches all the other fields cannot differ
+        // unless we have a bug.
+        if (!mAlgorithm.equals(other.mAlgorithm)
+                || !mAuthorizations.equals(other.mAuthorizations)
+                || !mDescriptor.equals(other.mDescriptor)) {
+            Log.e("AndroidKeyStoreKey", "Bug: key ids are identical, but key metadata"
+                    + "differs.");
+            return false;
+        }
+        return true;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreKeyFactorySpi.java

@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.security.KeyStore;
+import android.security.keystore.KeyGenParameterSpec;
+import android.security.keystore.KeyInfo;
+
+import java.security.InvalidKeyException;
+import java.security.Key;
+import java.security.KeyFactorySpi;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+import java.security.spec.ECPublicKeySpec;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.KeySpec;
+import java.security.spec.PKCS8EncodedKeySpec;
+import java.security.spec.RSAPublicKeySpec;
+import java.security.spec.X509EncodedKeySpec;
+
+/**
+ * {@link KeyFactorySpi} backed by Android KeyStore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreKeyFactorySpi extends KeyFactorySpi {
+
+    private final KeyStore mKeyStore = KeyStore.getInstance();
+
+    @Override
+    protected <T extends KeySpec> T engineGetKeySpec(Key key, Class<T> keySpecClass)
+            throws InvalidKeySpecException {
+        if (key == null) {
+            throw new InvalidKeySpecException("key == null");
+        } else if ((!(key instanceof AndroidKeyStorePrivateKey))
+            && (!(key instanceof AndroidKeyStorePublicKey))) {
+            throw new InvalidKeySpecException(
+                    "Unsupported key type: " + key.getClass().getName()
+                    + ". This KeyFactory supports only Android Keystore asymmetric keys");
+        }
+
+        // key is an Android Keystore private or public key
+
+        if (keySpecClass == null) {
+            throw new InvalidKeySpecException("keySpecClass == null");
+        } else if (KeyInfo.class.equals(keySpecClass)) {
+            if (!(key instanceof AndroidKeyStorePrivateKey)) {
+                throw new InvalidKeySpecException(
+                        "Unsupported key type: " + key.getClass().getName()
+                        + ". KeyInfo can be obtained only for Android Keystore private keys");
+            }
+            AndroidKeyStorePrivateKey keystorePrivateKey = (AndroidKeyStorePrivateKey) key;
+            @SuppressWarnings("unchecked")
+            T result = (T) AndroidKeyStoreSecretKeyFactorySpi.getKeyInfo(keystorePrivateKey);
+            return result;
+        } else if (X509EncodedKeySpec.class.equals(keySpecClass)) {
+            if (!(key instanceof AndroidKeyStorePublicKey)) {
+                throw new InvalidKeySpecException(
+                        "Unsupported key type: " + key.getClass().getName()
+                        + ". X509EncodedKeySpec can be obtained only for Android Keystore public"
+                        + " keys");
+            }
+            @SuppressWarnings("unchecked")
+            T result = (T) new X509EncodedKeySpec(((AndroidKeyStorePublicKey) key).getEncoded());
+            return result;
+        } else if (PKCS8EncodedKeySpec.class.equals(keySpecClass)) {
+            if (key instanceof AndroidKeyStorePrivateKey) {
+                throw new InvalidKeySpecException(
+                        "Key material export of Android Keystore private keys is not supported");
+            } else {
+                throw new InvalidKeySpecException(
+                        "Cannot export key material of public key in PKCS#8 format."
+                        + " Only X.509 format (X509EncodedKeySpec) supported for public keys.");
+            }
+        } else if (RSAPublicKeySpec.class.equals(keySpecClass)) {
+            if (key instanceof AndroidKeyStoreRSAPublicKey) {
+                AndroidKeyStoreRSAPublicKey rsaKey = (AndroidKeyStoreRSAPublicKey) key;
+                @SuppressWarnings("unchecked")
+                T result =
+                        (T) new RSAPublicKeySpec(rsaKey.getModulus(), rsaKey.getPublicExponent());
+                return result;
+            } else {
+                throw new InvalidKeySpecException(
+                        "Obtaining RSAPublicKeySpec not supported for " + key.getAlgorithm() + " "
+                        + ((key instanceof AndroidKeyStorePrivateKey) ? "private" : "public")
+                        + " key");
+            }
+        } else if (ECPublicKeySpec.class.equals(keySpecClass)) {
+            if (key instanceof AndroidKeyStoreECPublicKey) {
+                AndroidKeyStoreECPublicKey ecKey = (AndroidKeyStoreECPublicKey) key;
+                @SuppressWarnings("unchecked")
+                T result = (T) new ECPublicKeySpec(ecKey.getW(), ecKey.getParams());
+                return result;
+            } else {
+                throw new InvalidKeySpecException(
+                        "Obtaining ECPublicKeySpec not supported for " + key.getAlgorithm() + " "
+                        + ((key instanceof AndroidKeyStorePrivateKey) ? "private" : "public")
+                        + " key");
+            }
+        } else {
+            throw new InvalidKeySpecException("Unsupported key spec: " + keySpecClass.getName());
+        }
+    }
+
+    @Override
+    protected PrivateKey engineGeneratePrivate(KeySpec spec) throws InvalidKeySpecException {
+        throw new InvalidKeySpecException(
+                "To generate a key pair in Android Keystore, use KeyPairGenerator initialized with"
+                + " " + KeyGenParameterSpec.class.getName());
+    }
+
+    @Override
+    protected PublicKey engineGeneratePublic(KeySpec spec) throws InvalidKeySpecException {
+        throw new InvalidKeySpecException(
+                "To generate a key pair in Android Keystore, use KeyPairGenerator initialized with"
+                + " " + KeyGenParameterSpec.class.getName());
+    }
+
+    @Override
+    protected Key engineTranslateKey(Key key) throws InvalidKeyException {
+        if (key == null) {
+            throw new InvalidKeyException("key == null");
+        } else if ((!(key instanceof AndroidKeyStorePrivateKey))
+                && (!(key instanceof AndroidKeyStorePublicKey))) {
+            throw new InvalidKeyException(
+                    "To import a key into Android Keystore, use KeyStore.setEntry");
+        }
+        return key;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreKeyGeneratorSpi.java

@@ -0,0 +1,428 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.security.KeyStore2;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keymaster.KeymasterArguments;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+import android.security.keystore.KeyGenParameterSpec;
+import android.security.keystore.KeyProperties;
+import android.security.keystore.KeymasterUtils;
+import android.security.keystore.StrongBoxUnavailableException;
+import android.system.keystore2.Domain;
+import android.system.keystore2.IKeystoreSecurityLevel;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+import android.system.keystore2.KeyParameter;
+import android.system.keystore2.SecurityLevel;
+import android.util.Log;
+
+import libcore.util.EmptyArray;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.ProviderException;
+import java.security.SecureRandom;
+import java.security.spec.AlgorithmParameterSpec;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import javax.crypto.KeyGeneratorSpi;
+import javax.crypto.SecretKey;
+
+/**
+ * {@link KeyGeneratorSpi} backed by Android KeyStore.
+ *
+ * @hide
+ */
+public abstract class AndroidKeyStoreKeyGeneratorSpi extends KeyGeneratorSpi {
+    private static final String TAG = "AndroidKeyStoreKeyGeneratorSpi";
+
+    public static class AES extends AndroidKeyStoreKeyGeneratorSpi {
+        public AES() {
+            super(KeymasterDefs.KM_ALGORITHM_AES, 128);
+        }
+
+        @Override
+        protected void engineInit(AlgorithmParameterSpec params, SecureRandom random)
+                throws InvalidAlgorithmParameterException {
+            super.engineInit(params, random);
+            if ((mKeySizeBits != 128) && (mKeySizeBits != 192) && (mKeySizeBits != 256)) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported key size: " + mKeySizeBits
+                        + ". Supported: 128, 192, 256.");
+            }
+        }
+    }
+
+    public static class DESede extends AndroidKeyStoreKeyGeneratorSpi {
+        public DESede() {
+            super(KeymasterDefs.KM_ALGORITHM_3DES, 168);
+        }
+    }
+
+    protected static abstract class HmacBase extends AndroidKeyStoreKeyGeneratorSpi {
+        protected HmacBase(int keymasterDigest) {
+            super(KeymasterDefs.KM_ALGORITHM_HMAC,
+                    keymasterDigest,
+                    KeymasterUtils.getDigestOutputSizeBits(keymasterDigest));
+        }
+    }
+
+    public static class HmacSHA1 extends HmacBase {
+        public HmacSHA1() {
+            super(KeymasterDefs.KM_DIGEST_SHA1);
+        }
+    }
+
+    public static class HmacSHA224 extends HmacBase {
+        public HmacSHA224() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_224);
+        }
+    }
+
+    public static class HmacSHA256 extends HmacBase {
+        public HmacSHA256() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_256);
+        }
+    }
+
+    public static class HmacSHA384 extends HmacBase {
+        public HmacSHA384() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_384);
+        }
+    }
+
+    public static class HmacSHA512 extends HmacBase {
+        public HmacSHA512() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_512);
+        }
+    }
+
+    private final KeyStore2 mKeyStore = KeyStore2.getInstance();
+    private final int mKeymasterAlgorithm;
+    private final int mKeymasterDigest;
+    private final int mDefaultKeySizeBits;
+
+    private KeyGenParameterSpec mSpec;
+    private SecureRandom mRng;
+
+    protected int mKeySizeBits;
+    private int[] mKeymasterPurposes;
+    private int[] mKeymasterBlockModes;
+    private int[] mKeymasterPaddings;
+    private int[] mKeymasterDigests;
+
+    protected AndroidKeyStoreKeyGeneratorSpi(
+            int keymasterAlgorithm,
+            int defaultKeySizeBits) {
+        this(keymasterAlgorithm, -1, defaultKeySizeBits);
+    }
+
+    protected AndroidKeyStoreKeyGeneratorSpi(
+            int keymasterAlgorithm,
+            int keymasterDigest,
+            int defaultKeySizeBits) {
+        mKeymasterAlgorithm = keymasterAlgorithm;
+        mKeymasterDigest = keymasterDigest;
+        mDefaultKeySizeBits = defaultKeySizeBits;
+        if (mDefaultKeySizeBits <= 0) {
+            throw new IllegalArgumentException("Default key size must be positive");
+        }
+
+        if ((mKeymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_HMAC) && (mKeymasterDigest == -1)) {
+            throw new IllegalArgumentException(
+                    "Digest algorithm must be specified for HMAC key");
+        }
+    }
+
+    @Override
+    protected void engineInit(SecureRandom random) {
+        throw new UnsupportedOperationException("Cannot initialize without a "
+                + KeyGenParameterSpec.class.getName() + " parameter");
+    }
+
+    @Override
+    protected void engineInit(int keySize, SecureRandom random) {
+        throw new UnsupportedOperationException("Cannot initialize without a "
+                + KeyGenParameterSpec.class.getName() + " parameter");
+    }
+
+    @Override
+    protected void engineInit(AlgorithmParameterSpec params, SecureRandom random)
+            throws InvalidAlgorithmParameterException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            if ((params == null) || (!(params instanceof KeyGenParameterSpec))) {
+                throw new InvalidAlgorithmParameterException("Cannot initialize without a "
+                        + KeyGenParameterSpec.class.getName() + " parameter");
+            }
+            KeyGenParameterSpec spec = (KeyGenParameterSpec) params;
+            if (spec.getKeystoreAlias() == null) {
+                throw new InvalidAlgorithmParameterException("KeyStore entry alias not provided");
+            }
+
+            mRng = random;
+            mSpec = spec;
+
+            mKeySizeBits = (spec.getKeySize() != -1) ? spec.getKeySize() : mDefaultKeySizeBits;
+            if (mKeySizeBits <= 0) {
+                throw new InvalidAlgorithmParameterException(
+                        "Key size must be positive: " + mKeySizeBits);
+            } else if ((mKeySizeBits % 8) != 0) {
+                throw new InvalidAlgorithmParameterException(
+                        "Key size must be a multiple of 8: " + mKeySizeBits);
+            }
+
+            try {
+                mKeymasterPurposes = KeyProperties.Purpose.allToKeymaster(spec.getPurposes());
+                mKeymasterPaddings = KeyProperties.EncryptionPadding.allToKeymaster(
+                        spec.getEncryptionPaddings());
+                if (spec.getSignaturePaddings().length > 0) {
+                    throw new InvalidAlgorithmParameterException(
+                            "Signature paddings not supported for symmetric key algorithms");
+                }
+                mKeymasterBlockModes = KeyProperties.BlockMode.allToKeymaster(spec.getBlockModes());
+                if (((spec.getPurposes() & KeyProperties.PURPOSE_ENCRYPT) != 0)
+                        && (spec.isRandomizedEncryptionRequired())) {
+                    for (int keymasterBlockMode : mKeymasterBlockModes) {
+                        if (!KeymasterUtils.isKeymasterBlockModeIndCpaCompatibleWithSymmetricCrypto(
+                                keymasterBlockMode)) {
+                            throw new InvalidAlgorithmParameterException(
+                                    "Randomized encryption (IND-CPA) required but may be violated"
+                                    + " by block mode: "
+                                    + KeyProperties.BlockMode.fromKeymaster(keymasterBlockMode)
+                                    + ". See " + KeyGenParameterSpec.class.getName()
+                                    + " documentation.");
+                        }
+                    }
+                }
+                if (mKeymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_3DES) {
+                    if (mKeySizeBits != 168) {
+                        throw new InvalidAlgorithmParameterException(
+                            "3DES key size must be 168 bits.");
+                    }
+                }
+                if (mKeymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_HMAC) {
+                    if (mKeySizeBits < 64 || mKeySizeBits > 512) {
+                        throw new InvalidAlgorithmParameterException(
+                            "HMAC key sizes must be within 64-512 bits, inclusive.");
+                    }
+
+                    // JCA HMAC key algorithm implies a digest (e.g., HmacSHA256 key algorithm
+                    // implies SHA-256 digest). Because keymaster HMAC key is authorized only for
+                    // one digest, we don't let algorithm parameter spec override the digest implied
+                    // by the key. If the spec specifies digests at all, it must specify only one
+                    // digest, the only implied by key algorithm.
+                    mKeymasterDigests = new int[] {mKeymasterDigest};
+                    if (spec.isDigestsSpecified()) {
+                        // Digest(s) explicitly specified in the spec. Check that the list
+                        // consists of exactly one digest, the one implied by key algorithm.
+                        int[] keymasterDigestsFromSpec =
+                                KeyProperties.Digest.allToKeymaster(spec.getDigests());
+                        if ((keymasterDigestsFromSpec.length != 1)
+                                || (keymasterDigestsFromSpec[0] != mKeymasterDigest)) {
+                            throw new InvalidAlgorithmParameterException(
+                                    "Unsupported digests specification: "
+                                    + Arrays.asList(spec.getDigests()) + ". Only "
+                                    + KeyProperties.Digest.fromKeymaster(mKeymasterDigest)
+                                    + " supported for this HMAC key algorithm");
+                        }
+                    }
+                } else {
+                    // Key algorithm does not imply a digest.
+                    if (spec.isDigestsSpecified()) {
+                        mKeymasterDigests = KeyProperties.Digest.allToKeymaster(spec.getDigests());
+                    } else {
+                        mKeymasterDigests = EmptyArray.INT;
+                    }
+                }
+
+                // Check that user authentication related parameters are acceptable. This method
+                // will throw an IllegalStateException if there are issues (e.g., secure lock screen
+                // not set up).
+                KeymasterUtils.addUserAuthArgs(new KeymasterArguments(), spec);
+            } catch (IllegalStateException | IllegalArgumentException e) {
+                throw new InvalidAlgorithmParameterException(e);
+            }
+
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    private void resetAll() {
+        mSpec = null;
+        mRng = null;
+        mKeySizeBits = -1;
+        mKeymasterPurposes = null;
+        mKeymasterPaddings = null;
+        mKeymasterBlockModes = null;
+    }
+
+    @Override
+    protected SecretKey engineGenerateKey() {
+        KeyGenParameterSpec spec = mSpec;
+        if (spec == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+
+        List<KeyParameter> params = new ArrayList<>();
+
+        params.add(KeyStore2ParameterUtils.makeInt(
+                KeymasterDefs.KM_TAG_KEY_SIZE, mKeySizeBits
+        ));
+        params.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, mKeymasterAlgorithm
+        ));
+        ArrayUtils.forEach(mKeymasterPurposes, (purpose) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_PURPOSE, purpose
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterBlockModes, (blockMode) -> {
+            if (blockMode == KeymasterDefs.KM_MODE_GCM
+                    && mKeymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_AES) {
+                params.add(KeyStore2ParameterUtils.makeInt(
+                        KeymasterDefs.KM_TAG_MIN_MAC_LENGTH,
+                        AndroidKeyStoreAuthenticatedAESCipherSpi.GCM
+                                .MIN_SUPPORTED_TAG_LENGTH_BITS
+                ));
+            }
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_BLOCK_MODE, blockMode
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterPaddings, (padding) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_PADDING, padding
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterDigests, (digest) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_DIGEST, digest
+            ));
+        });
+
+        if (mKeymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_HMAC
+                && mKeymasterDigests.length != 0) {
+            int digestOutputSizeBits = KeymasterUtils.getDigestOutputSizeBits(mKeymasterDigests[0]);
+            if (digestOutputSizeBits == -1) {
+                throw new ProviderException(
+                        "HMAC key authorized for unsupported digest: "
+                                + KeyProperties.Digest.fromKeymaster(mKeymasterDigests[0]));
+            }
+            params.add(KeyStore2ParameterUtils.makeInt(
+                    KeymasterDefs.KM_TAG_MIN_MAC_LENGTH, digestOutputSizeBits
+            ));
+        }
+
+        KeyStore2ParameterUtils.addUserAuthArgs(params, spec);
+
+        if (spec.getKeyValidityStart() != null) {
+            params.add(KeyStore2ParameterUtils.makeDate(
+                    KeymasterDefs.KM_TAG_ACTIVE_DATETIME, spec.getKeyValidityStart()
+            ));
+        }
+        if (spec.getKeyValidityForOriginationEnd() != null) {
+            params.add(KeyStore2ParameterUtils.makeDate(
+                    KeymasterDefs.KM_TAG_ORIGINATION_EXPIRE_DATETIME,
+                    spec.getKeyValidityForOriginationEnd()
+            ));
+        }
+        if (spec.getKeyValidityForConsumptionEnd() != null) {
+            params.add(KeyStore2ParameterUtils.makeDate(
+                    KeymasterDefs.KM_TAG_USAGE_EXPIRE_DATETIME,
+                    spec.getKeyValidityForConsumptionEnd()
+            ));
+        }
+
+        if (((spec.getPurposes() & KeyProperties.PURPOSE_ENCRYPT) != 0)
+                && (!spec.isRandomizedEncryptionRequired())) {
+            // Permit caller-provided IV when encrypting with this key
+            params.add(KeyStore2ParameterUtils.makeBool(
+                    KeymasterDefs.KM_TAG_CALLER_NONCE
+            ));
+        }
+
+        byte[] additionalEntropy =
+                KeyStoreCryptoOperationUtils.getRandomBytesToMixIntoKeystoreRng(
+                        mRng, (mKeySizeBits + 7) / 8);
+
+        @SecurityLevel int securityLevel = SecurityLevel.TRUSTED_ENVIRONMENT;
+        if (spec.isStrongBoxBacked()) {
+            securityLevel = SecurityLevel.STRONGBOX;
+        }
+
+        int flags = 0;
+        if (spec.isCriticalToDeviceEncryption()) {
+            flags |= IKeystoreSecurityLevel.KEY_FLAG_AUTH_BOUND_WITHOUT_CRYPTOGRAPHIC_LSKF_BINDING;
+        }
+
+        KeyDescriptor descriptor = new KeyDescriptor();
+        descriptor.alias = spec.getKeystoreAlias();
+        descriptor.nspace = spec.getNamespace();
+        descriptor.domain = descriptor.nspace == KeyProperties.NAMESPACE_APPLICATION
+                ? Domain.APP
+                : Domain.SELINUX;
+        descriptor.blob = null;
+
+        KeyMetadata metadata = null;
+        KeyStoreSecurityLevel iSecurityLevel = null;
+        try {
+            iSecurityLevel = mKeyStore.getSecurityLevel(securityLevel);
+            metadata = iSecurityLevel.generateKey(
+                    descriptor,
+                    null, /* Attestation key not applicable to symmetric keys. */
+                    params,
+                    flags,
+                    additionalEntropy);
+        } catch (android.security.KeyStoreException e) {
+            switch (e.getErrorCode()) {
+                // TODO replace with ErrorCode.HARDWARE_TYPE_UNAVAILABLE when KeyMint spec
+                //      becomes available.
+                case KeymasterDefs.KM_ERROR_HARDWARE_TYPE_UNAVAILABLE:
+                    throw new StrongBoxUnavailableException("Failed to generate key");
+                default:
+                    throw new ProviderException("Keystore key generation failed", e);
+            }
+        }
+        @KeyProperties.KeyAlgorithmEnum String keyAlgorithmJCA;
+        try {
+            keyAlgorithmJCA = KeyProperties.KeyAlgorithm.fromKeymasterSecretKeyAlgorithm(
+                    mKeymasterAlgorithm, mKeymasterDigest);
+        } catch (IllegalArgumentException e) {
+            try {
+                mKeyStore.deleteKey(descriptor);
+            } catch (android.security.KeyStoreException kse) {
+                Log.e(TAG, "Failed to delete key after generating successfully but"
+                        + " failed to get the algorithm string.", kse);
+            }
+            throw new ProviderException("Failed to obtain JCA secret key algorithm name", e);
+        }
+        SecretKey result = new AndroidKeyStoreSecretKey(descriptor, metadata, keyAlgorithmJCA,
+                iSecurityLevel);
+        return result;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreKeyPairGeneratorSpi.java

@@ -0,0 +1,804 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.os.Build;
+import android.security.KeyPairGeneratorSpec;
+import android.security.KeyStore2;
+import android.security.KeyStoreException;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keymaster.KeymasterArguments;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+import android.security.keystore.KeyGenParameterSpec;
+import android.security.keystore.KeyProperties;
+import android.security.keystore.KeymasterUtils;
+import android.security.keystore.SecureKeyImportUnavailableException;
+import android.security.keystore.StrongBoxUnavailableException;
+import android.system.keystore2.Domain;
+import android.system.keystore2.IKeystoreSecurityLevel;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+import android.system.keystore2.KeyParameter;
+import android.system.keystore2.ResponseCode;
+import android.system.keystore2.SecurityLevel;
+import android.util.Log;
+
+import libcore.util.EmptyArray;
+
+import java.math.BigInteger;
+import java.nio.charset.StandardCharsets;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.KeyPairGeneratorSpi;
+import java.security.ProviderException;
+import java.security.SecureRandom;
+import java.security.UnrecoverableKeyException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.ECGenParameterSpec;
+import java.security.spec.RSAKeyGenParameterSpec;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Provides a way to create instances of a KeyPair which will be placed in the
+ * Android keystore service usable only by the application that called it. This
+ * can be used in conjunction with
+ * {@link java.security.KeyStore#getInstance(String)} using the
+ * {@code "AndroidKeyStore"} type.
+ * <p>
+ * This class can not be directly instantiated and must instead be used via the
+ * {@link KeyPairGenerator#getInstance(String)
+ * KeyPairGenerator.getInstance("AndroidKeyStore")} API.
+ *
+ * @hide
+ */
+public abstract class AndroidKeyStoreKeyPairGeneratorSpi extends KeyPairGeneratorSpi {
+    private static final String TAG = "AndroidKeyStoreKeyPairGeneratorSpi";
+
+    public static class RSA extends AndroidKeyStoreKeyPairGeneratorSpi {
+        public RSA() {
+            super(KeymasterDefs.KM_ALGORITHM_RSA);
+        }
+    }
+
+    public static class EC extends AndroidKeyStoreKeyPairGeneratorSpi {
+        public EC() {
+            super(KeymasterDefs.KM_ALGORITHM_EC);
+        }
+    }
+
+    /*
+     * These must be kept in sync with system/security/keystore/defaults.h
+     */
+
+    /* EC */
+    private static final int EC_DEFAULT_KEY_SIZE = 256;
+
+    /* RSA */
+    private static final int RSA_DEFAULT_KEY_SIZE = 2048;
+    private static final int RSA_MIN_KEY_SIZE = 512;
+    private static final int RSA_MAX_KEY_SIZE = 8192;
+
+    private static final Map<String, Integer> SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE =
+            new HashMap<String, Integer>();
+    private static final List<String> SUPPORTED_EC_NIST_CURVE_NAMES = new ArrayList<String>();
+    private static final List<Integer> SUPPORTED_EC_NIST_CURVE_SIZES = new ArrayList<Integer>();
+    static {
+        // Aliases for NIST P-224
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("p-224", 224);
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("secp224r1", 224);
+
+
+        // Aliases for NIST P-256
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("p-256", 256);
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("secp256r1", 256);
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("prime256v1", 256);
+
+        // Aliases for NIST P-384
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("p-384", 384);
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("secp384r1", 384);
+
+        // Aliases for NIST P-521
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("p-521", 521);
+        SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.put("secp521r1", 521);
+
+        SUPPORTED_EC_NIST_CURVE_NAMES.addAll(SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.keySet());
+        Collections.sort(SUPPORTED_EC_NIST_CURVE_NAMES);
+
+        SUPPORTED_EC_NIST_CURVE_SIZES.addAll(
+                new HashSet<Integer>(SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.values()));
+        Collections.sort(SUPPORTED_EC_NIST_CURVE_SIZES);
+    }
+
+    private final int mOriginalKeymasterAlgorithm;
+
+    private KeyStore2 mKeyStore;
+
+    private KeyGenParameterSpec mSpec;
+
+    private String mEntryAlias;
+    private int mEntryUid;
+    private @KeyProperties.KeyAlgorithmEnum String mJcaKeyAlgorithm;
+    private int mKeymasterAlgorithm = -1;
+    private int mKeySizeBits;
+    private SecureRandom mRng;
+
+    private int[] mKeymasterPurposes;
+    private int[] mKeymasterBlockModes;
+    private int[] mKeymasterEncryptionPaddings;
+    private int[] mKeymasterSignaturePaddings;
+    private int[] mKeymasterDigests;
+
+    private Long mRSAPublicExponent;
+
+    protected AndroidKeyStoreKeyPairGeneratorSpi(int keymasterAlgorithm) {
+        mOriginalKeymasterAlgorithm = keymasterAlgorithm;
+    }
+
+    @SuppressWarnings("deprecation")
+    @Override
+    public void initialize(int keysize, SecureRandom random) {
+        throw new IllegalArgumentException(
+                KeyGenParameterSpec.class.getName() + " or " + KeyPairGeneratorSpec.class.getName()
+                + " required to initialize this KeyPairGenerator");
+    }
+
+    @SuppressWarnings("deprecation")
+    @Override
+    public void initialize(AlgorithmParameterSpec params, SecureRandom random)
+            throws InvalidAlgorithmParameterException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            if (params == null) {
+                throw new InvalidAlgorithmParameterException(
+                        "Must supply params of type " + KeyGenParameterSpec.class.getName()
+                        + " or " + KeyPairGeneratorSpec.class.getName());
+            }
+
+            KeyGenParameterSpec spec;
+            boolean encryptionAtRestRequired = false;
+            int keymasterAlgorithm = mOriginalKeymasterAlgorithm;
+            if (params instanceof KeyGenParameterSpec) {
+                spec = (KeyGenParameterSpec) params;
+            } else if (params instanceof KeyPairGeneratorSpec) {
+                // Legacy/deprecated spec
+                KeyPairGeneratorSpec legacySpec = (KeyPairGeneratorSpec) params;
+                try {
+                    KeyGenParameterSpec.Builder specBuilder;
+                    String specKeyAlgorithm = legacySpec.getKeyType();
+                    if (specKeyAlgorithm != null) {
+                        // Spec overrides the generator's default key algorithm
+                        try {
+                            keymasterAlgorithm =
+                                    KeyProperties.KeyAlgorithm.toKeymasterAsymmetricKeyAlgorithm(
+                                            specKeyAlgorithm);
+                        } catch (IllegalArgumentException e) {
+                            throw new InvalidAlgorithmParameterException(
+                                    "Invalid key type in parameters", e);
+                        }
+                    }
+                    switch (keymasterAlgorithm) {
+                        case KeymasterDefs.KM_ALGORITHM_EC:
+                            specBuilder = new KeyGenParameterSpec.Builder(
+                                    legacySpec.getKeystoreAlias(),
+                                    KeyProperties.PURPOSE_SIGN
+                                    | KeyProperties.PURPOSE_VERIFY);
+                            // Authorized to be used with any digest (including no digest).
+                            // MD5 was never offered for Android Keystore for ECDSA.
+                            specBuilder.setDigests(
+                                    KeyProperties.DIGEST_NONE,
+                                    KeyProperties.DIGEST_SHA1,
+                                    KeyProperties.DIGEST_SHA224,
+                                    KeyProperties.DIGEST_SHA256,
+                                    KeyProperties.DIGEST_SHA384,
+                                    KeyProperties.DIGEST_SHA512);
+                            break;
+                        case KeymasterDefs.KM_ALGORITHM_RSA:
+                            specBuilder = new KeyGenParameterSpec.Builder(
+                                    legacySpec.getKeystoreAlias(),
+                                    KeyProperties.PURPOSE_ENCRYPT
+                                    | KeyProperties.PURPOSE_DECRYPT
+                                    | KeyProperties.PURPOSE_SIGN
+                                    | KeyProperties.PURPOSE_VERIFY);
+                            // Authorized to be used with any digest (including no digest).
+                            specBuilder.setDigests(
+                                    KeyProperties.DIGEST_NONE,
+                                    KeyProperties.DIGEST_MD5,
+                                    KeyProperties.DIGEST_SHA1,
+                                    KeyProperties.DIGEST_SHA224,
+                                    KeyProperties.DIGEST_SHA256,
+                                    KeyProperties.DIGEST_SHA384,
+                                    KeyProperties.DIGEST_SHA512);
+                            // Authorized to be used with any encryption and signature padding
+                            // schemes (including no padding).
+                            specBuilder.setEncryptionPaddings(
+                                    KeyProperties.ENCRYPTION_PADDING_NONE,
+                                    KeyProperties.ENCRYPTION_PADDING_RSA_PKCS1,
+                                    KeyProperties.ENCRYPTION_PADDING_RSA_OAEP);
+                            specBuilder.setSignaturePaddings(
+                                    KeyProperties.SIGNATURE_PADDING_RSA_PKCS1,
+                                    KeyProperties.SIGNATURE_PADDING_RSA_PSS);
+                            // Disable randomized encryption requirement to support encryption
+                            // padding NONE above.
+                            specBuilder.setRandomizedEncryptionRequired(false);
+                            break;
+                        default:
+                            throw new ProviderException(
+                                    "Unsupported algorithm: " + mKeymasterAlgorithm);
+                    }
+
+                    if (legacySpec.getKeySize() != -1) {
+                        specBuilder.setKeySize(legacySpec.getKeySize());
+                    }
+                    if (legacySpec.getAlgorithmParameterSpec() != null) {
+                        specBuilder.setAlgorithmParameterSpec(
+                                legacySpec.getAlgorithmParameterSpec());
+                    }
+                    specBuilder.setCertificateSubject(legacySpec.getSubjectDN());
+                    specBuilder.setCertificateSerialNumber(legacySpec.getSerialNumber());
+                    specBuilder.setCertificateNotBefore(legacySpec.getStartDate());
+                    specBuilder.setCertificateNotAfter(legacySpec.getEndDate());
+                    specBuilder.setUserAuthenticationRequired(false);
+
+                    spec = specBuilder.build();
+                } catch (NullPointerException | IllegalArgumentException e) {
+                    throw new InvalidAlgorithmParameterException(e);
+                }
+            } else {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported params class: " + params.getClass().getName()
+                        + ". Supported: " + KeyGenParameterSpec.class.getName()
+                        + ", " + KeyPairGeneratorSpec.class.getName());
+            }
+
+            mEntryAlias = spec.getKeystoreAlias();
+            mEntryUid = spec.getUid();
+            mSpec = spec;
+            mKeymasterAlgorithm = keymasterAlgorithm;
+            mKeySizeBits = spec.getKeySize();
+            initAlgorithmSpecificParameters();
+            if (mKeySizeBits == -1) {
+                mKeySizeBits = getDefaultKeySize(keymasterAlgorithm);
+            }
+            checkValidKeySize(keymasterAlgorithm, mKeySizeBits, mSpec.isStrongBoxBacked());
+
+            if (spec.getKeystoreAlias() == null) {
+                throw new InvalidAlgorithmParameterException("KeyStore entry alias not provided");
+            }
+
+            String jcaKeyAlgorithm;
+            try {
+                jcaKeyAlgorithm = KeyProperties.KeyAlgorithm.fromKeymasterAsymmetricKeyAlgorithm(
+                        keymasterAlgorithm);
+                mKeymasterPurposes = KeyProperties.Purpose.allToKeymaster(spec.getPurposes());
+                mKeymasterBlockModes = KeyProperties.BlockMode.allToKeymaster(spec.getBlockModes());
+                mKeymasterEncryptionPaddings = KeyProperties.EncryptionPadding.allToKeymaster(
+                        spec.getEncryptionPaddings());
+                if (((spec.getPurposes() & KeyProperties.PURPOSE_ENCRYPT) != 0)
+                        && (spec.isRandomizedEncryptionRequired())) {
+                    for (int keymasterPadding : mKeymasterEncryptionPaddings) {
+                        if (!KeymasterUtils
+                                .isKeymasterPaddingSchemeIndCpaCompatibleWithAsymmetricCrypto(
+                                        keymasterPadding)) {
+                            throw new InvalidAlgorithmParameterException(
+                                    "Randomized encryption (IND-CPA) required but may be violated"
+                                    + " by padding scheme: "
+                                    + KeyProperties.EncryptionPadding.fromKeymaster(
+                                            keymasterPadding)
+                                    + ". See " + KeyGenParameterSpec.class.getName()
+                                    + " documentation.");
+                        }
+                    }
+                }
+                mKeymasterSignaturePaddings = KeyProperties.SignaturePadding.allToKeymaster(
+                        spec.getSignaturePaddings());
+                if (spec.isDigestsSpecified()) {
+                    mKeymasterDigests = KeyProperties.Digest.allToKeymaster(spec.getDigests());
+                } else {
+                    mKeymasterDigests = EmptyArray.INT;
+                }
+
+                // Check that user authentication related parameters are acceptable. This method
+                // will throw an IllegalStateException if there are issues (e.g., secure lock screen
+                // not set up).
+                KeymasterUtils.addUserAuthArgs(new KeymasterArguments(), mSpec);
+            } catch (IllegalArgumentException | IllegalStateException e) {
+                throw new InvalidAlgorithmParameterException(e);
+            }
+
+            mJcaKeyAlgorithm = jcaKeyAlgorithm;
+            mRng = random;
+            mKeyStore = KeyStore2.getInstance();
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    private void resetAll() {
+        mEntryAlias = null;
+        mEntryUid = KeyProperties.NAMESPACE_APPLICATION;
+        mJcaKeyAlgorithm = null;
+        mKeymasterAlgorithm = -1;
+        mKeymasterPurposes = null;
+        mKeymasterBlockModes = null;
+        mKeymasterEncryptionPaddings = null;
+        mKeymasterSignaturePaddings = null;
+        mKeymasterDigests = null;
+        mKeySizeBits = 0;
+        mSpec = null;
+        mRSAPublicExponent = null;
+        mRng = null;
+        mKeyStore = null;
+    }
+
+    private void initAlgorithmSpecificParameters() throws InvalidAlgorithmParameterException {
+        AlgorithmParameterSpec algSpecificSpec = mSpec.getAlgorithmParameterSpec();
+        switch (mKeymasterAlgorithm) {
+            case KeymasterDefs.KM_ALGORITHM_RSA:
+            {
+                BigInteger publicExponent = null;
+                if (algSpecificSpec instanceof RSAKeyGenParameterSpec) {
+                    RSAKeyGenParameterSpec rsaSpec = (RSAKeyGenParameterSpec) algSpecificSpec;
+                    if (mKeySizeBits == -1) {
+                        mKeySizeBits = rsaSpec.getKeysize();
+                    } else if (mKeySizeBits != rsaSpec.getKeysize()) {
+                        throw new InvalidAlgorithmParameterException("RSA key size must match "
+                                + " between " + mSpec + " and " + algSpecificSpec
+                                + ": " + mKeySizeBits + " vs " + rsaSpec.getKeysize());
+                    }
+                    publicExponent = rsaSpec.getPublicExponent();
+                } else if (algSpecificSpec != null) {
+                    throw new InvalidAlgorithmParameterException(
+                        "RSA may only use RSAKeyGenParameterSpec");
+                }
+                if (publicExponent == null) {
+                    publicExponent = RSAKeyGenParameterSpec.F4;
+                }
+                if (publicExponent.compareTo(BigInteger.ZERO) < 1) {
+                    throw new InvalidAlgorithmParameterException(
+                            "RSA public exponent must be positive: " + publicExponent);
+                }
+                if ((publicExponent.signum() == -1)
+                        || (publicExponent.compareTo(KeymasterArguments.UINT64_MAX_VALUE) > 0)) {
+                    throw new InvalidAlgorithmParameterException(
+                            "Unsupported RSA public exponent: " + publicExponent
+                            + ". Maximum supported value: " + KeymasterArguments.UINT64_MAX_VALUE);
+                }
+                mRSAPublicExponent = publicExponent.longValue();
+                break;
+            }
+            case KeymasterDefs.KM_ALGORITHM_EC:
+                if (algSpecificSpec instanceof ECGenParameterSpec) {
+                    ECGenParameterSpec ecSpec = (ECGenParameterSpec) algSpecificSpec;
+                    String curveName = ecSpec.getName();
+                    Integer ecSpecKeySizeBits = SUPPORTED_EC_NIST_CURVE_NAME_TO_SIZE.get(
+                            curveName.toLowerCase(Locale.US));
+                    if (ecSpecKeySizeBits == null) {
+                        throw new InvalidAlgorithmParameterException(
+                                "Unsupported EC curve name: " + curveName
+                                + ". Supported: " + SUPPORTED_EC_NIST_CURVE_NAMES);
+                    }
+                    if (mKeySizeBits == -1) {
+                        mKeySizeBits = ecSpecKeySizeBits;
+                    } else if (mKeySizeBits != ecSpecKeySizeBits) {
+                        throw new InvalidAlgorithmParameterException("EC key size must match "
+                                + " between " + mSpec + " and " + algSpecificSpec
+                                + ": " + mKeySizeBits + " vs " + ecSpecKeySizeBits);
+                    }
+                } else if (algSpecificSpec != null) {
+                    throw new InvalidAlgorithmParameterException(
+                        "EC may only use ECGenParameterSpec");
+                }
+                break;
+            default:
+                throw new ProviderException("Unsupported algorithm: " + mKeymasterAlgorithm);
+        }
+    }
+
+    @Override
+    public KeyPair generateKeyPair() {
+        if (mKeyStore == null || mSpec == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+
+        final @SecurityLevel int securityLevel =
+                mSpec.isStrongBoxBacked()
+                        ? SecurityLevel.STRONGBOX
+                        : SecurityLevel.TRUSTED_ENVIRONMENT;
+
+        final int flags =
+                mSpec.isCriticalToDeviceEncryption()
+                        ? IKeystoreSecurityLevel
+                                .KEY_FLAG_AUTH_BOUND_WITHOUT_CRYPTOGRAPHIC_LSKF_BINDING
+                        : 0;
+
+        byte[] additionalEntropy =
+                KeyStoreCryptoOperationUtils.getRandomBytesToMixIntoKeystoreRng(
+                        mRng, (mKeySizeBits + 7) / 8);
+
+        KeyDescriptor descriptor = new KeyDescriptor();
+        descriptor.alias = mEntryAlias;
+        descriptor.domain = mEntryUid == KeyProperties.NAMESPACE_APPLICATION
+                ? Domain.APP
+                : Domain.SELINUX;
+        descriptor.nspace = mEntryUid;
+        descriptor.blob = null;
+
+        boolean success = false;
+        try {
+            KeyStoreSecurityLevel iSecurityLevel = mKeyStore.getSecurityLevel(securityLevel);
+
+            KeyMetadata metadata = iSecurityLevel.generateKey(descriptor, null,
+                    constructKeyGenerationArguments(), flags, additionalEntropy);
+
+            AndroidKeyStorePublicKey publicKey =
+                    AndroidKeyStoreProvider.makeAndroidKeyStorePublicKeyFromKeyEntryResponse(
+                            descriptor, metadata, iSecurityLevel, mKeymasterAlgorithm);
+
+            success = true;
+            return new KeyPair(publicKey, publicKey.getPrivateKey());
+        } catch (android.security.KeyStoreException e) {
+            switch(e.getErrorCode()) {
+                case KeymasterDefs.KM_ERROR_HARDWARE_TYPE_UNAVAILABLE:
+                    throw new StrongBoxUnavailableException("Failed to generated key pair.", e);
+                default:
+                    ProviderException p = new ProviderException("Failed to generate key pair.", e);
+                    if ((mSpec.getPurposes() & KeyProperties.PURPOSE_WRAP_KEY) != 0) {
+                        throw new SecureKeyImportUnavailableException(p);
+                    }
+                    throw p;
+            }
+        } catch (UnrecoverableKeyException e) {
+            throw new ProviderException(
+                    "Failed to construct key object from newly generated key pair.", e);
+        } finally {
+            if (!success) {
+                try {
+                    mKeyStore.deleteKey(descriptor);
+                } catch (KeyStoreException e) {
+                    if (e.getErrorCode() != ResponseCode.KEY_NOT_FOUND) {
+                        Log.e(TAG, "Failed to delete newly generated key after "
+                                + "generation failed unexpectedly.", e);
+                    }
+                }
+            }
+        }
+    }
+
+    private void addAttestationParameters(@NonNull List<KeyParameter> params)
+            throws ProviderException {
+        byte[] challenge = mSpec.getAttestationChallenge();
+
+        if (challenge != null) {
+            params.add(KeyStore2ParameterUtils.makeBytes(
+                    KeymasterDefs.KM_TAG_ATTESTATION_CHALLENGE, challenge
+            ));
+
+            if (mSpec.isDevicePropertiesAttestationIncluded()) {
+                params.add(KeyStore2ParameterUtils.makeBytes(
+                        KeymasterDefs.KM_TAG_ATTESTATION_ID_BRAND,
+                        Build.BRAND.getBytes(StandardCharsets.UTF_8)
+                ));
+                params.add(KeyStore2ParameterUtils.makeBytes(
+                        KeymasterDefs.KM_TAG_ATTESTATION_ID_DEVICE,
+                        Build.DEVICE.getBytes(StandardCharsets.UTF_8)
+                ));
+                params.add(KeyStore2ParameterUtils.makeBytes(
+                        KeymasterDefs.KM_TAG_ATTESTATION_ID_PRODUCT,
+                        Build.PRODUCT.getBytes(StandardCharsets.UTF_8)
+                ));
+                params.add(KeyStore2ParameterUtils.makeBytes(
+                        KeymasterDefs.KM_TAG_ATTESTATION_ID_MANUFACTURER,
+                        Build.MANUFACTURER.getBytes(StandardCharsets.UTF_8)
+                ));
+                params.add(KeyStore2ParameterUtils.makeBytes(
+                        KeymasterDefs.KM_TAG_ATTESTATION_ID_MODEL,
+                        Build.MODEL.getBytes(StandardCharsets.UTF_8)
+                ));
+            }
+        } else {
+            if (mSpec.isDevicePropertiesAttestationIncluded()) {
+                throw new ProviderException("An attestation challenge must be provided when "
+                        + "requesting device properties attestation.");
+            }
+        }
+    }
+
+    private Collection<KeyParameter> constructKeyGenerationArguments() {
+        List<KeyParameter> params = new ArrayList<>();
+        params.add(KeyStore2ParameterUtils.makeInt(KeymasterDefs.KM_TAG_KEY_SIZE, mKeySizeBits));
+        params.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, mKeymasterAlgorithm
+        ));
+        ArrayUtils.forEach(mKeymasterPurposes, (purpose) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_PURPOSE, purpose
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterBlockModes, (blockMode) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_BLOCK_MODE, blockMode
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterEncryptionPaddings, (padding) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_PADDING, padding
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterSignaturePaddings, (padding) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_PADDING, padding
+            ));
+        });
+        ArrayUtils.forEach(mKeymasterDigests, (digest) -> {
+            params.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_DIGEST, digest
+            ));
+        });
+
+        KeyStore2ParameterUtils.addUserAuthArgs(params, mSpec);
+
+        if (mSpec.getKeyValidityStart() != null) {
+            params.add(KeyStore2ParameterUtils.makeDate(
+                    KeymasterDefs.KM_TAG_ACTIVE_DATETIME, mSpec.getKeyValidityStart()
+            ));
+        }
+        if (mSpec.getKeyValidityForOriginationEnd() != null) {
+            params.add(KeyStore2ParameterUtils.makeDate(
+                    KeymasterDefs.KM_TAG_ORIGINATION_EXPIRE_DATETIME,
+                    mSpec.getKeyValidityForOriginationEnd()
+            ));
+        }
+        if (mSpec.getKeyValidityForConsumptionEnd() != null) {
+            params.add(KeyStore2ParameterUtils.makeDate(
+                    KeymasterDefs.KM_TAG_USAGE_EXPIRE_DATETIME,
+                    mSpec.getKeyValidityForConsumptionEnd()
+            ));
+        }
+
+        addAlgorithmSpecificParameters(params);
+
+        if (mSpec.isUniqueIdIncluded()) {
+            params.add(KeyStore2ParameterUtils.makeBool(KeymasterDefs.KM_TAG_INCLUDE_UNIQUE_ID));
+        }
+
+        addAttestationParameters(params);
+
+        return params;
+    }
+
+    private void addAlgorithmSpecificParameters(List<KeyParameter> params) {
+        switch (mKeymasterAlgorithm) {
+            case KeymasterDefs.KM_ALGORITHM_RSA:
+                params.add(KeyStore2ParameterUtils.makeLong(
+                        KeymasterDefs.KM_TAG_RSA_PUBLIC_EXPONENT, mRSAPublicExponent
+                ));
+                break;
+            case KeymasterDefs.KM_ALGORITHM_EC:
+                break;
+            default:
+                throw new ProviderException("Unsupported algorithm: " + mKeymasterAlgorithm);
+        }
+    }
+
+    private static int getDefaultKeySize(int keymasterAlgorithm) {
+        switch (keymasterAlgorithm) {
+            case KeymasterDefs.KM_ALGORITHM_EC:
+                return EC_DEFAULT_KEY_SIZE;
+            case KeymasterDefs.KM_ALGORITHM_RSA:
+                return RSA_DEFAULT_KEY_SIZE;
+            default:
+                throw new ProviderException("Unsupported algorithm: " + keymasterAlgorithm);
+        }
+    }
+
+    private static void checkValidKeySize(
+            int keymasterAlgorithm,
+            int keySize,
+            boolean isStrongBoxBacked)
+            throws InvalidAlgorithmParameterException {
+        switch (keymasterAlgorithm) {
+            case KeymasterDefs.KM_ALGORITHM_EC:
+                if (isStrongBoxBacked && keySize != 256) {
+                    throw new InvalidAlgorithmParameterException(
+                            "Unsupported StrongBox EC key size: "
+                            + keySize + " bits. Supported: 256");
+                }
+                if (!SUPPORTED_EC_NIST_CURVE_SIZES.contains(keySize)) {
+                    throw new InvalidAlgorithmParameterException("Unsupported EC key size: "
+                            + keySize + " bits. Supported: " + SUPPORTED_EC_NIST_CURVE_SIZES);
+                }
+                break;
+            case KeymasterDefs.KM_ALGORITHM_RSA:
+                if (keySize < RSA_MIN_KEY_SIZE || keySize > RSA_MAX_KEY_SIZE) {
+                    throw new InvalidAlgorithmParameterException("RSA key size must be >= "
+                            + RSA_MIN_KEY_SIZE + " and <= " + RSA_MAX_KEY_SIZE);
+                }
+                break;
+            default:
+                throw new ProviderException("Unsupported algorithm: " + keymasterAlgorithm);
+        }
+    }
+
+    /**
+     * Returns the {@code Signature} algorithm to be used for signing a certificate using the
+     * specified key or {@code null} if the key cannot be used for signing a certificate.
+     */
+    @Nullable
+    private static String getCertificateSignatureAlgorithm(
+            int keymasterAlgorithm,
+            int keySizeBits,
+            KeyGenParameterSpec spec) {
+        // Constraints:
+        // 1. Key must be authorized for signing without user authentication.
+        // 2. Signature digest must be one of key's authorized digests.
+        // 3. For RSA keys, the digest output size must not exceed modulus size minus space overhead
+        //    of RSA PKCS#1 signature padding scheme (about 30 bytes).
+        // 4. For EC keys, the there is no point in using a digest whose output size is longer than
+        //    key/field size because the digest will be truncated to that size.
+
+        if ((spec.getPurposes() & KeyProperties.PURPOSE_SIGN) == 0) {
+            // Key not authorized for signing
+            return null;
+        }
+        if (spec.isUserAuthenticationRequired()) {
+            // Key not authorized for use without user authentication
+            return null;
+        }
+        if (!spec.isDigestsSpecified()) {
+            // Key not authorized for any digests -- can't sign
+            return null;
+        }
+        switch (keymasterAlgorithm) {
+            case KeymasterDefs.KM_ALGORITHM_EC:
+            {
+                Set<Integer> availableKeymasterDigests = getAvailableKeymasterSignatureDigests(
+                        spec.getDigests(),
+                        AndroidKeyStoreBCWorkaroundProvider.getSupportedEcdsaSignatureDigests());
+
+                int bestKeymasterDigest = -1;
+                int bestDigestOutputSizeBits = -1;
+                for (int keymasterDigest : availableKeymasterDigests) {
+                    int outputSizeBits = KeymasterUtils.getDigestOutputSizeBits(keymasterDigest);
+                    if (outputSizeBits == keySizeBits) {
+                        // Perfect match -- use this digest
+                        bestKeymasterDigest = keymasterDigest;
+                        bestDigestOutputSizeBits = outputSizeBits;
+                        break;
+                    }
+                    // Not a perfect match -- check against the best digest so far
+                    if (bestKeymasterDigest == -1) {
+                        // First digest tested -- definitely the best so far
+                        bestKeymasterDigest = keymasterDigest;
+                        bestDigestOutputSizeBits = outputSizeBits;
+                    } else {
+                        // Prefer output size to be as close to key size as possible, with output
+                        // sizes larger than key size preferred to those smaller than key size.
+                        if (bestDigestOutputSizeBits < keySizeBits) {
+                            // Output size of the best digest so far is smaller than key size.
+                            // Anything larger is a win.
+                            if (outputSizeBits > bestDigestOutputSizeBits) {
+                                bestKeymasterDigest = keymasterDigest;
+                                bestDigestOutputSizeBits = outputSizeBits;
+                            }
+                        } else {
+                            // Output size of the best digest so far is larger than key size.
+                            // Anything smaller is a win, as long as it's not smaller than key size.
+                            if ((outputSizeBits < bestDigestOutputSizeBits)
+                                    && (outputSizeBits >= keySizeBits)) {
+                                bestKeymasterDigest = keymasterDigest;
+                                bestDigestOutputSizeBits = outputSizeBits;
+                            }
+                        }
+                    }
+                }
+                if (bestKeymasterDigest == -1) {
+                    return null;
+                }
+                return KeyProperties.Digest.fromKeymasterToSignatureAlgorithmDigest(
+                        bestKeymasterDigest) + "WithECDSA";
+            }
+            case KeymasterDefs.KM_ALGORITHM_RSA:
+            {
+                // Check whether this key is authorized for PKCS#1 signature padding.
+                // We use Bouncy Castle to generate self-signed RSA certificates. Bouncy Castle
+                // only supports RSA certificates signed using PKCS#1 padding scheme. The key needs
+                // to be authorized for PKCS#1 padding or padding NONE which means any padding.
+                boolean pkcs1SignaturePaddingSupported =
+                        com.android.internal.util.ArrayUtils.contains(
+                                KeyProperties.SignaturePadding.allToKeymaster(
+                                        spec.getSignaturePaddings()),
+                                KeymasterDefs.KM_PAD_RSA_PKCS1_1_5_SIGN);
+                if (!pkcs1SignaturePaddingSupported) {
+                    // Key not authorized for PKCS#1 signature padding -- can't sign
+                    return null;
+                }
+
+                Set<Integer> availableKeymasterDigests = getAvailableKeymasterSignatureDigests(
+                        spec.getDigests(),
+                        AndroidKeyStoreBCWorkaroundProvider.getSupportedEcdsaSignatureDigests());
+
+                // The amount of space available for the digest is less than modulus size by about
+                // 30 bytes because padding must be at least 11 bytes long (00 || 01 || PS || 00,
+                // where PS must be at least 8 bytes long), and then there's also the 15--19 bytes
+                // overhead (depending the on chosen digest) for encoding digest OID and digest
+                // value in DER.
+                int maxDigestOutputSizeBits = keySizeBits - 30 * 8;
+                int bestKeymasterDigest = -1;
+                int bestDigestOutputSizeBits = -1;
+                for (int keymasterDigest : availableKeymasterDigests) {
+                    int outputSizeBits = KeymasterUtils.getDigestOutputSizeBits(keymasterDigest);
+                    if (outputSizeBits > maxDigestOutputSizeBits) {
+                        // Digest too long (signature generation will fail) -- skip
+                        continue;
+                    }
+                    if (bestKeymasterDigest == -1) {
+                        // First digest tested -- definitely the best so far
+                        bestKeymasterDigest = keymasterDigest;
+                        bestDigestOutputSizeBits = outputSizeBits;
+                    } else {
+                        // The longer the better
+                        if (outputSizeBits > bestDigestOutputSizeBits) {
+                            bestKeymasterDigest = keymasterDigest;
+                            bestDigestOutputSizeBits = outputSizeBits;
+                        }
+                    }
+                }
+                if (bestKeymasterDigest == -1) {
+                    return null;
+                }
+                return KeyProperties.Digest.fromKeymasterToSignatureAlgorithmDigest(
+                        bestKeymasterDigest) + "WithRSA";
+            }
+            default:
+                throw new ProviderException("Unsupported algorithm: " + keymasterAlgorithm);
+        }
+    }
+
+    private static Set<Integer> getAvailableKeymasterSignatureDigests(
+            @KeyProperties.DigestEnum String[] authorizedKeyDigests,
+            @KeyProperties.DigestEnum String[] supportedSignatureDigests) {
+        Set<Integer> authorizedKeymasterKeyDigests = new HashSet<Integer>();
+        for (int keymasterDigest : KeyProperties.Digest.allToKeymaster(authorizedKeyDigests)) {
+            authorizedKeymasterKeyDigests.add(keymasterDigest);
+        }
+        Set<Integer> supportedKeymasterSignatureDigests = new HashSet<Integer>();
+        for (int keymasterDigest
+                : KeyProperties.Digest.allToKeymaster(supportedSignatureDigests)) {
+            supportedKeymasterSignatureDigests.add(keymasterDigest);
+        }
+        Set<Integer> result = new HashSet<Integer>(supportedKeymasterSignatureDigests);
+        result.retainAll(authorizedKeymasterKeyDigests);
+        return result;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreLoadStoreParameter.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import java.security.KeyStore;
+import java.security.KeyStore.ProtectionParameter;
+
+/**
+ * @hide
+ */
+class AndroidKeyStoreLoadStoreParameter implements KeyStore.LoadStoreParameter {
+
+    private final int mNamespace;
+
+    AndroidKeyStoreLoadStoreParameter(int namespace) {
+        mNamespace = namespace;
+    }
+
+    @Override
+    public ProtectionParameter getProtectionParameter() {
+        return null;
+    }
+
+    int getNamespace() {
+        return mNamespace;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStorePrivateKey.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.KeyDescriptor;
+
+import java.security.PrivateKey;
+
+/**
+ * {@link PrivateKey} backed by Android Keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStorePrivateKey extends AndroidKeyStoreKey implements PrivateKey {
+
+    public AndroidKeyStorePrivateKey(@NonNull KeyDescriptor descriptor,
+            long keyId, @NonNull Authorization[] authorizations, @NonNull String algorithm,
+            @NonNull KeyStoreSecurityLevel securityLevel) {
+        super(descriptor, keyId, authorizations, algorithm, securityLevel);
+    }
+
+}

keystore/java/android/security/keystore2/AndroidKeyStoreProvider.java

@@ -0,0 +1,415 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStore;
+import android.security.KeyStore2;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyPermanentlyInvalidatedException;
+import android.security.keystore.KeyProperties;
+import android.security.keystore.KeyStoreCryptoOperation;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.Domain;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyEntryResponse;
+import android.system.keystore2.KeyMetadata;
+import android.system.keystore2.ResponseCode;
+
+import java.security.KeyFactory;
+import java.security.KeyPair;
+import java.security.NoSuchAlgorithmException;
+import java.security.Provider;
+import java.security.ProviderException;
+import java.security.PublicKey;
+import java.security.Security;
+import java.security.Signature;
+import java.security.UnrecoverableKeyException;
+import java.security.interfaces.ECPublicKey;
+import java.security.interfaces.RSAPublicKey;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.X509EncodedKeySpec;
+
+import javax.crypto.Cipher;
+import javax.crypto.Mac;
+
+/**
+ * A provider focused on providing JCA interfaces for the Android KeyStore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreProvider extends Provider {
+    private static final String PROVIDER_NAME = "AndroidKeyStore";
+
+    // IMPLEMENTATION NOTE: Class names are hard-coded in this provider to avoid loading these
+    // classes when this provider is instantiated and installed early on during each app's
+    // initialization process.
+    //
+    // Crypto operations operating on the AndroidKeyStore keys must not be offered by this provider.
+    // Instead, they need to be offered by AndroidKeyStoreBCWorkaroundProvider. See its Javadoc
+    // for details.
+
+    private static final String PACKAGE_NAME = "android.security.keystore2";
+
+    private static final String DESEDE_SYSTEM_PROPERTY =
+            "ro.hardware.keystore_desede";
+
+    /** @hide **/
+    public AndroidKeyStoreProvider() {
+        super(PROVIDER_NAME, 1.0, "Android KeyStore security provider");
+
+        boolean supports3DES = "true".equals(android.os.SystemProperties.get(DESEDE_SYSTEM_PROPERTY));
+
+        // java.security.KeyStore
+        put("KeyStore.AndroidKeyStore", PACKAGE_NAME + ".AndroidKeyStoreSpi");
+
+        // java.security.KeyPairGenerator
+        put("KeyPairGenerator.EC", PACKAGE_NAME + ".AndroidKeyStoreKeyPairGeneratorSpi$EC");
+        put("KeyPairGenerator.RSA", PACKAGE_NAME +  ".AndroidKeyStoreKeyPairGeneratorSpi$RSA");
+
+        // java.security.KeyFactory
+        putKeyFactoryImpl("EC");
+        putKeyFactoryImpl("RSA");
+
+        // javax.crypto.KeyGenerator
+        put("KeyGenerator.AES", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$AES");
+        put("KeyGenerator.HmacSHA1", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA1");
+        put("KeyGenerator.HmacSHA224", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA224");
+        put("KeyGenerator.HmacSHA256", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA256");
+        put("KeyGenerator.HmacSHA384", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA384");
+        put("KeyGenerator.HmacSHA512", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$HmacSHA512");
+
+        if (supports3DES) {
+            put("KeyGenerator.DESede", PACKAGE_NAME + ".AndroidKeyStoreKeyGeneratorSpi$DESede");
+        }
+
+        // java.security.SecretKeyFactory
+        putSecretKeyFactoryImpl("AES");
+        if (supports3DES) {
+            putSecretKeyFactoryImpl("DESede");
+        }
+        putSecretKeyFactoryImpl("HmacSHA1");
+        putSecretKeyFactoryImpl("HmacSHA224");
+        putSecretKeyFactoryImpl("HmacSHA256");
+        putSecretKeyFactoryImpl("HmacSHA384");
+        putSecretKeyFactoryImpl("HmacSHA512");
+    }
+
+    private static boolean sInstalled = false;
+
+    /**
+     * This function indicates whether or not this provider was installed. This is manly used
+     * as indicator for
+     * {@link android.security.keystore.AndroidKeyStoreProvider#getKeyStoreForUid(int)}
+     * to whether or not to retrieve the Keystore provider by "AndroidKeyStoreLegacy".
+     * This function can be removed once the transition to Keystore 2.0 is complete.
+     * b/171305684
+     *
+     * @return true if this provider was installed.
+     * @hide
+     */
+    public static boolean isInstalled() {
+        return sInstalled;
+    }
+
+    /**
+     * Installs a new instance of this provider (and the
+     * {@link AndroidKeyStoreBCWorkaroundProvider}).
+     * @hide
+     */
+    public static void install() {
+        Provider[] providers = Security.getProviders();
+        int bcProviderIndex = -1;
+        for (int i = 0; i < providers.length; i++) {
+            Provider provider = providers[i];
+            if ("BC".equals(provider.getName())) {
+                bcProviderIndex = i;
+                break;
+            }
+        }
+        sInstalled = true;
+
+        Security.addProvider(new AndroidKeyStoreProvider());
+        Security.addProvider(
+                new android.security.keystore.AndroidKeyStoreProvider(
+                        "AndroidKeyStoreLegacy"));
+        Provider workaroundProvider = new AndroidKeyStoreBCWorkaroundProvider();
+        Provider legacyWorkaroundProvider =
+                new android.security.keystore.AndroidKeyStoreBCWorkaroundProvider(
+                        "AndroidKeyStoreBCWorkaroundLegacy");
+        if (bcProviderIndex != -1) {
+            // Bouncy Castle provider found -- install the workaround provider above it.
+            // insertProviderAt uses 1-based positions.
+            Security.insertProviderAt(legacyWorkaroundProvider, bcProviderIndex + 1);
+            Security.insertProviderAt(workaroundProvider, bcProviderIndex + 1);
+        } else {
+            // Bouncy Castle provider not found -- install the workaround provider at lowest
+            // priority.
+            Security.addProvider(workaroundProvider);
+            Security.addProvider(legacyWorkaroundProvider);
+        }
+    }
+
+    private void putSecretKeyFactoryImpl(String algorithm) {
+        put("SecretKeyFactory." + algorithm, PACKAGE_NAME + ".AndroidKeyStoreSecretKeyFactorySpi");
+    }
+
+    private void putKeyFactoryImpl(String algorithm) {
+        put("KeyFactory." + algorithm, PACKAGE_NAME + ".AndroidKeyStoreKeyFactorySpi");
+    }
+
+    /**
+     * Gets the {@link KeyStore} operation handle corresponding to the provided JCA crypto
+     * primitive.
+     *
+     * <p>The following primitives are supported: {@link Cipher} and {@link Mac}.
+     *
+     * @return KeyStore operation handle or {@code 0} if the provided primitive's KeyStore operation
+     *         is not in progress.
+     *
+     * @throws IllegalArgumentException if the provided primitive is not supported or is not backed
+     *         by AndroidKeyStore provider.
+     * @throws IllegalStateException if the provided primitive is not initialized.
+     * @hide
+     */
+    public static long getKeyStoreOperationHandle(Object cryptoPrimitive) {
+        if (cryptoPrimitive == null) {
+            throw new NullPointerException();
+        }
+        Object spi;
+        if (cryptoPrimitive instanceof Signature) {
+            spi = ((Signature) cryptoPrimitive).getCurrentSpi();
+        } else if (cryptoPrimitive instanceof Mac) {
+            spi = ((Mac) cryptoPrimitive).getCurrentSpi();
+        } else if (cryptoPrimitive instanceof Cipher) {
+            spi = ((Cipher) cryptoPrimitive).getCurrentSpi();
+        } else {
+            throw new IllegalArgumentException("Unsupported crypto primitive: " + cryptoPrimitive
+                    + ". Supported: Signature, Mac, Cipher");
+        }
+        if (spi == null) {
+            throw new IllegalStateException("Crypto primitive not initialized");
+        } else if (!(spi instanceof KeyStoreCryptoOperation)) {
+            throw new IllegalArgumentException(
+                    "Crypto primitive not backed by AndroidKeyStore provider: " + cryptoPrimitive
+                    + ", spi: " + spi);
+        }
+        return ((KeyStoreCryptoOperation) spi).getOperationHandle();
+    }
+
+    /**
+     * This helper function gets called if the key loaded from the keystore daemon
+     * is for an asymmetric algorithm. It constructs an instance of {@link AndroidKeyStorePublicKey}
+     * which implements {@link PublicKey}.
+     *
+     * @param descriptor The original key descriptor that was used to load the key.
+     *
+     * @param metadata The key metadata which includes the public key material, a reference to the
+     *                 stored private key material, the key characteristics.
+     * @param iSecurityLevel A binder interface that allows using the private key.
+     * @param algorithm Must indicate EC or RSA.
+     * @return AndroidKeyStorePublicKey
+     * @throws UnrecoverableKeyException
+     * @hide
+     */
+    @NonNull
+    static AndroidKeyStorePublicKey makeAndroidKeyStorePublicKeyFromKeyEntryResponse(
+            @NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata,
+            @NonNull KeyStoreSecurityLevel iSecurityLevel, int algorithm)
+            throws UnrecoverableKeyException {
+        if (metadata.certificate == null) {
+            throw new UnrecoverableKeyException("Failed to obtain X.509 form of public key."
+                    + " Keystore has no public certificate stored.");
+        }
+        final byte[] x509EncodedPublicKey = metadata.certificate;
+
+        String jcaKeyAlgorithm;
+        try {
+            jcaKeyAlgorithm = KeyProperties.KeyAlgorithm.fromKeymasterAsymmetricKeyAlgorithm(
+                    algorithm);
+        } catch (IllegalArgumentException e) {
+            throw (UnrecoverableKeyException)
+                    new UnrecoverableKeyException("Failed to load private key")
+                            .initCause(e);
+        }
+
+        PublicKey publicKey;
+        try {
+            KeyFactory keyFactory = KeyFactory.getInstance(jcaKeyAlgorithm);
+            publicKey = keyFactory.generatePublic(new X509EncodedKeySpec(x509EncodedPublicKey));
+        } catch (NoSuchAlgorithmException e) {
+            throw new ProviderException(
+                    "Failed to obtain " + jcaKeyAlgorithm + " KeyFactory", e);
+        } catch (InvalidKeySpecException e) {
+            throw new ProviderException("Invalid X.509 encoding of public key", e);
+        }
+
+        KeyStoreSecurityLevel securityLevel = iSecurityLevel;
+        if (KeyProperties.KEY_ALGORITHM_EC.equalsIgnoreCase(jcaKeyAlgorithm)) {
+
+            return new AndroidKeyStoreECPublicKey(descriptor, metadata,
+                    iSecurityLevel, (ECPublicKey) publicKey);
+        } else if (KeyProperties.KEY_ALGORITHM_RSA.equalsIgnoreCase(jcaKeyAlgorithm)) {
+            return new AndroidKeyStoreRSAPublicKey(descriptor, metadata,
+                    iSecurityLevel, (RSAPublicKey) publicKey);
+        } else {
+            throw new ProviderException("Unsupported Android Keystore public key algorithm: "
+                    + jcaKeyAlgorithm);
+        }
+    }
+
+    /** @hide **/
+    @NonNull
+    public static AndroidKeyStorePublicKey loadAndroidKeyStorePublicKeyFromKeystore(
+            @NonNull KeyStore2 keyStore, @NonNull String privateKeyAlias, int namespace)
+            throws UnrecoverableKeyException, KeyPermanentlyInvalidatedException {
+        AndroidKeyStoreKey key =
+                loadAndroidKeyStoreKeyFromKeystore(keyStore, privateKeyAlias, namespace);
+        if (key instanceof AndroidKeyStorePublicKey) {
+            return (AndroidKeyStorePublicKey) key;
+        } else {
+            throw new UnrecoverableKeyException("No asymmetric key found by the given alias.");
+        }
+    }
+
+    /** @hide **/
+    @NonNull
+    public static KeyPair loadAndroidKeyStoreKeyPairFromKeystore(
+            @NonNull KeyStore2 keyStore, @NonNull String privateKeyAlias, int namespace)
+            throws UnrecoverableKeyException, KeyPermanentlyInvalidatedException {
+        AndroidKeyStoreKey key =
+                loadAndroidKeyStoreKeyFromKeystore(keyStore, privateKeyAlias, namespace);
+        if (key instanceof AndroidKeyStorePublicKey) {
+            AndroidKeyStorePublicKey publicKey = (AndroidKeyStorePublicKey) key;
+            return new KeyPair(publicKey, publicKey.getPrivateKey());
+        } else {
+            throw new UnrecoverableKeyException("No asymmetric key found by the given alias.");
+        }
+    }
+
+    /** @hide **/
+    @NonNull
+    public static AndroidKeyStorePrivateKey loadAndroidKeyStorePrivateKeyFromKeystore(
+            @NonNull KeyStore2 keyStore, @NonNull String privateKeyAlias, int namespace)
+            throws UnrecoverableKeyException, KeyPermanentlyInvalidatedException {
+        AndroidKeyStoreKey key =
+                loadAndroidKeyStoreKeyFromKeystore(keyStore, privateKeyAlias, namespace);
+        if (key instanceof AndroidKeyStorePublicKey) {
+            return ((AndroidKeyStorePublicKey) key).getPrivateKey();
+        } else {
+            throw new UnrecoverableKeyException("No asymmetric key found by the given alias.");
+        }
+    }
+
+
+    @NonNull
+    private static AndroidKeyStoreSecretKey makeAndroidKeyStoreSecretKeyFromKeyEntryResponse(
+            @NonNull KeyDescriptor descriptor,
+            @NonNull KeyEntryResponse response, int algorithm, int digest)
+            throws UnrecoverableKeyException {
+
+        @KeyProperties.KeyAlgorithmEnum String keyAlgorithmString;
+        try {
+            keyAlgorithmString = KeyProperties.KeyAlgorithm.fromKeymasterSecretKeyAlgorithm(
+                    algorithm, digest);
+        } catch (IllegalArgumentException e) {
+            throw (UnrecoverableKeyException)
+                    new UnrecoverableKeyException("Unsupported secret key type").initCause(e);
+        }
+
+        return new AndroidKeyStoreSecretKey(descriptor,
+                response.metadata, keyAlgorithmString,
+                new KeyStoreSecurityLevel(response.iSecurityLevel));
+    }
+
+    /**
+     * Loads an an AndroidKeyStoreKey from the AndroidKeyStore backend.
+     *
+     * @param keyStore The keystore2 backend.
+     * @param alias The alias of the key in the Keystore database.
+     * @param namespace The a Keystore namespace. This is used by system api only to request
+     *                  Android system specific keystore namespace, which can be configured
+     *                  in the device's SEPolicy. Third party apps and most system components
+     *                  set this parameter to -1 to indicate their application specific namespace.
+     *                  TODO b/171806779 link to public Keystore 2.0 documentation.
+     *                       See bug for more details for now.
+     * @hide
+     **/
+    @NonNull
+    public static AndroidKeyStoreKey loadAndroidKeyStoreKeyFromKeystore(
+            @NonNull KeyStore2 keyStore, @NonNull String alias, int namespace)
+            throws UnrecoverableKeyException, KeyPermanentlyInvalidatedException  {
+
+        KeyDescriptor descriptor = new KeyDescriptor();
+        if (namespace == KeyProperties.NAMESPACE_APPLICATION) {
+            descriptor.nspace = 0; // ignored;
+            descriptor.domain = Domain.APP;
+        } else {
+            descriptor.nspace = namespace;
+            descriptor.domain = Domain.SELINUX;
+        }
+        descriptor.alias = alias;
+        descriptor.blob = null;
+        KeyEntryResponse response = null;
+        try {
+            response = keyStore.getKeyEntry(descriptor);
+        } catch (android.security.KeyStoreException e) {
+            if (e.getErrorCode() == ResponseCode.KEY_PERMANENTLY_INVALIDATED) {
+                throw new KeyPermanentlyInvalidatedException(
+                        "User changed or deleted their auth credentials",
+                        e);
+            } else {
+                throw (UnrecoverableKeyException)
+                        new UnrecoverableKeyException("Failed to obtain information about key")
+                                .initCause(e);
+            }
+        }
+
+        Integer keymasterAlgorithm = null;
+        // We just need one digest for the algorithm name
+        int keymasterDigest = -1;
+        for (Authorization a : response.metadata.authorizations) {
+            switch (a.keyParameter.tag) {
+                case KeymasterDefs.KM_TAG_ALGORITHM:
+                    keymasterAlgorithm = a.keyParameter.integer;
+                    break;
+                case KeymasterDefs.KM_TAG_DIGEST:
+                    if (keymasterDigest == -1) keymasterDigest = a.keyParameter.integer;
+                    break;
+            }
+        }
+        if (keymasterAlgorithm == null) {
+            throw new UnrecoverableKeyException("Key algorithm unknown");
+        }
+
+        if (keymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_HMAC ||
+                keymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_AES ||
+                keymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_3DES) {
+            return makeAndroidKeyStoreSecretKeyFromKeyEntryResponse(descriptor, response,
+                    keymasterAlgorithm, keymasterDigest);
+        } else if (keymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_RSA ||
+                keymasterAlgorithm == KeymasterDefs.KM_ALGORITHM_EC) {
+            return makeAndroidKeyStorePublicKeyFromKeyEntryResponse(descriptor, response.metadata,
+                    new KeyStoreSecurityLevel(response.iSecurityLevel),
+                    keymasterAlgorithm);
+        } else {
+            throw new UnrecoverableKeyException("Key algorithm unknown");
+        }
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStorePublicKey.java

@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keystore.ArrayUtils;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+
+import java.security.PublicKey;
+
+/**
+ * {@link PublicKey} backed by Android Keystore.
+ *
+ * @hide
+ */
+public abstract class AndroidKeyStorePublicKey extends AndroidKeyStoreKey implements PublicKey {
+    private final byte[] mCertificate;
+    private final byte[] mCertificateChain;
+
+    public AndroidKeyStorePublicKey(@NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata, @NonNull String algorithm,
+            @NonNull KeyStoreSecurityLevel securityLevel) {
+        super(descriptor, metadata.key.nspace, metadata.authorizations, algorithm, securityLevel);
+        mCertificate = metadata.certificate;
+        mCertificateChain = metadata.certificateChain;
+    }
+
+    abstract AndroidKeyStorePrivateKey getPrivateKey();
+
+    @Override
+    public String getFormat() {
+        return "X.509";
+    }
+
+    @Override
+    public byte[] getEncoded() {
+        return ArrayUtils.cloneIfNotEmpty(mCertificate);
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+
+        result = prime * result + super.hashCode();
+        result = prime * result + ((mCertificate == null) ? 0 : mCertificate.hashCode());
+        result = prime * result + ((mCertificateChain == null) ? 0 : mCertificateChain.hashCode());
+
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (!super.equals(obj)) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        return true;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreRSACipherSpi.java

@@ -0,0 +1,525 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyProperties;
+import android.security.keystore.KeymasterUtils;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.KeyParameter;
+
+import java.security.AlgorithmParameters;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.Key;
+import java.security.NoSuchAlgorithmException;
+import java.security.PrivateKey;
+import java.security.ProviderException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidParameterSpecException;
+import java.security.spec.MGF1ParameterSpec;
+import java.util.List;
+
+import javax.crypto.Cipher;
+import javax.crypto.CipherSpi;
+import javax.crypto.spec.OAEPParameterSpec;
+import javax.crypto.spec.PSource;
+
+/**
+ * Base class for {@link CipherSpi} providing Android KeyStore backed RSA encryption/decryption.
+ *
+ * @hide
+ */
+abstract class AndroidKeyStoreRSACipherSpi extends AndroidKeyStoreCipherSpiBase {
+
+    /**
+     * Raw RSA cipher without any padding.
+     */
+    public static final class NoPadding extends AndroidKeyStoreRSACipherSpi {
+        public NoPadding() {
+            super(KeymasterDefs.KM_PAD_NONE);
+        }
+
+        @Override
+        protected boolean adjustConfigForEncryptingWithPrivateKey() {
+            // RSA encryption with no padding using private key is a way to implement raw RSA
+            // signatures which JCA does not expose via Signature. We thus have to support this.
+            setKeymasterPurposeOverride(KeymasterDefs.KM_PURPOSE_SIGN);
+            return true;
+        }
+
+        @Override
+        protected void initAlgorithmSpecificParameters() throws InvalidKeyException {}
+
+        @Override
+        protected void initAlgorithmSpecificParameters(@Nullable AlgorithmParameterSpec params)
+                throws InvalidAlgorithmParameterException {
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unexpected parameters: " + params + ". No parameters supported");
+            }
+        }
+
+        @Override
+        protected void initAlgorithmSpecificParameters(@Nullable AlgorithmParameters params)
+                throws InvalidAlgorithmParameterException {
+
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unexpected parameters: " + params + ". No parameters supported");
+            }
+        }
+
+        @Override
+        protected AlgorithmParameters engineGetParameters() {
+            return null;
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForBegin() {
+            return 0;
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForFinish() {
+            return 0;
+        }
+    }
+
+    /**
+     * RSA cipher with PKCS#1 v1.5 encryption padding.
+     */
+    public static final class PKCS1Padding extends AndroidKeyStoreRSACipherSpi {
+        public PKCS1Padding() {
+            super(KeymasterDefs.KM_PAD_RSA_PKCS1_1_5_ENCRYPT);
+        }
+
+        @Override
+        protected boolean adjustConfigForEncryptingWithPrivateKey() {
+            // RSA encryption with PCKS#1 padding using private key is a way to implement RSA
+            // signatures with PKCS#1 padding. We have to support this for legacy reasons.
+            setKeymasterPurposeOverride(KeymasterDefs.KM_PURPOSE_SIGN);
+            setKeymasterPaddingOverride(KeymasterDefs.KM_PAD_RSA_PKCS1_1_5_SIGN);
+            return true;
+        }
+
+        @Override
+        protected void initAlgorithmSpecificParameters() throws InvalidKeyException {}
+
+        @Override
+        protected void initAlgorithmSpecificParameters(@Nullable AlgorithmParameterSpec params)
+                throws InvalidAlgorithmParameterException {
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unexpected parameters: " + params + ". No parameters supported");
+            }
+        }
+
+        @Override
+        protected void initAlgorithmSpecificParameters(@Nullable AlgorithmParameters params)
+                throws InvalidAlgorithmParameterException {
+
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unexpected parameters: " + params + ". No parameters supported");
+            }
+        }
+
+        @Override
+        protected AlgorithmParameters engineGetParameters() {
+            return null;
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForBegin() {
+            return 0;
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForFinish() {
+            return (isEncrypting()) ? getModulusSizeBytes() : 0;
+        }
+    }
+
+    /**
+     * RSA cipher with OAEP encryption padding. Only SHA-1 based MGF1 is supported as MGF.
+     */
+    abstract static class OAEPWithMGF1Padding extends AndroidKeyStoreRSACipherSpi {
+
+        private static final String MGF_ALGORITGM_MGF1 = "MGF1";
+
+        private int mKeymasterDigest = -1;
+        private int mDigestOutputSizeBytes;
+
+        OAEPWithMGF1Padding(int keymasterDigest) {
+            super(KeymasterDefs.KM_PAD_RSA_OAEP);
+            mKeymasterDigest = keymasterDigest;
+            mDigestOutputSizeBytes =
+                    (KeymasterUtils.getDigestOutputSizeBits(keymasterDigest) + 7) / 8;
+        }
+
+        @Override
+        protected final void initAlgorithmSpecificParameters() throws InvalidKeyException {}
+
+        @Override
+        protected final void initAlgorithmSpecificParameters(
+                @Nullable AlgorithmParameterSpec params) throws InvalidAlgorithmParameterException {
+            if (params == null) {
+                return;
+            }
+
+            if (!(params instanceof OAEPParameterSpec)) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported parameter spec: " + params
+                        + ". Only OAEPParameterSpec supported");
+            }
+            OAEPParameterSpec spec = (OAEPParameterSpec) params;
+            if (!MGF_ALGORITGM_MGF1.equalsIgnoreCase(spec.getMGFAlgorithm())) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported MGF: " + spec.getMGFAlgorithm()
+                        + ". Only " + MGF_ALGORITGM_MGF1 + " supported");
+            }
+            String jcaDigest = spec.getDigestAlgorithm();
+            int keymasterDigest;
+            try {
+                keymasterDigest = KeyProperties.Digest.toKeymaster(jcaDigest);
+            } catch (IllegalArgumentException e) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported digest: " + jcaDigest, e);
+            }
+            switch (keymasterDigest) {
+                case KeymasterDefs.KM_DIGEST_SHA1:
+                case KeymasterDefs.KM_DIGEST_SHA_2_224:
+                case KeymasterDefs.KM_DIGEST_SHA_2_256:
+                case KeymasterDefs.KM_DIGEST_SHA_2_384:
+                case KeymasterDefs.KM_DIGEST_SHA_2_512:
+                    // Permitted.
+                    break;
+                default:
+                    throw new InvalidAlgorithmParameterException(
+                            "Unsupported digest: " + jcaDigest);
+            }
+            AlgorithmParameterSpec mgfParams = spec.getMGFParameters();
+            if (mgfParams == null) {
+                throw new InvalidAlgorithmParameterException("MGF parameters must be provided");
+            }
+            // Check whether MGF parameters match the OAEPParameterSpec
+            if (!(mgfParams instanceof MGF1ParameterSpec)) {
+                throw new InvalidAlgorithmParameterException("Unsupported MGF parameters"
+                        + ": " + mgfParams + ". Only MGF1ParameterSpec supported");
+            }
+            MGF1ParameterSpec mgfSpec = (MGF1ParameterSpec) mgfParams;
+            String mgf1JcaDigest = mgfSpec.getDigestAlgorithm();
+            if (!KeyProperties.DIGEST_SHA1.equalsIgnoreCase(mgf1JcaDigest)) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported MGF1 digest: " + mgf1JcaDigest
+                        + ". Only " + KeyProperties.DIGEST_SHA1 + " supported");
+            }
+            PSource pSource = spec.getPSource();
+            if (!(pSource instanceof PSource.PSpecified)) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported source of encoding input P: " + pSource
+                        + ". Only pSpecifiedEmpty (PSource.PSpecified.DEFAULT) supported");
+            }
+            PSource.PSpecified pSourceSpecified = (PSource.PSpecified) pSource;
+            byte[] pSourceValue = pSourceSpecified.getValue();
+            if ((pSourceValue != null) && (pSourceValue.length > 0)) {
+                throw new InvalidAlgorithmParameterException(
+                        "Unsupported source of encoding input P: " + pSource
+                        + ". Only pSpecifiedEmpty (PSource.PSpecified.DEFAULT) supported");
+            }
+            mKeymasterDigest = keymasterDigest;
+            mDigestOutputSizeBytes =
+                    (KeymasterUtils.getDigestOutputSizeBits(keymasterDigest) + 7) / 8;
+        }
+
+        @Override
+        protected final void initAlgorithmSpecificParameters(@Nullable AlgorithmParameters params)
+                throws InvalidAlgorithmParameterException {
+            if (params == null) {
+                return;
+            }
+
+            OAEPParameterSpec spec;
+            try {
+                spec = params.getParameterSpec(OAEPParameterSpec.class);
+            } catch (InvalidParameterSpecException e) {
+                throw new InvalidAlgorithmParameterException("OAEP parameters required"
+                        + ", but not found in parameters: " + params, e);
+            }
+            if (spec == null) {
+                throw new InvalidAlgorithmParameterException("OAEP parameters required"
+                        + ", but not provided in parameters: " + params);
+            }
+            initAlgorithmSpecificParameters(spec);
+        }
+
+        @Override
+        protected final AlgorithmParameters engineGetParameters() {
+            OAEPParameterSpec spec =
+                    new OAEPParameterSpec(
+                            KeyProperties.Digest.fromKeymaster(mKeymasterDigest),
+                            MGF_ALGORITGM_MGF1,
+                            MGF1ParameterSpec.SHA1,
+                            PSource.PSpecified.DEFAULT);
+            try {
+                AlgorithmParameters params = AlgorithmParameters.getInstance("OAEP");
+                params.init(spec);
+                return params;
+            } catch (NoSuchAlgorithmException e) {
+                throw new ProviderException(
+                        "Failed to obtain OAEP AlgorithmParameters", e);
+            } catch (InvalidParameterSpecException e) {
+                throw new ProviderException(
+                        "Failed to initialize OAEP AlgorithmParameters with an IV",
+                        e);
+            }
+        }
+
+        @Override
+        protected final void addAlgorithmSpecificParametersToBegin(
+                @NonNull List<KeyParameter> parameters) {
+            super.addAlgorithmSpecificParametersToBegin(parameters);
+            parameters.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_DIGEST, mKeymasterDigest
+            ));
+        }
+
+        @Override
+        protected final void loadAlgorithmSpecificParametersFromBeginResult(
+                KeyParameter[] parameters) {
+            super.loadAlgorithmSpecificParametersFromBeginResult(parameters);
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForBegin() {
+            return 0;
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForFinish() {
+            return (isEncrypting()) ? mDigestOutputSizeBytes : 0;
+        }
+    }
+
+    public static class OAEPWithSHA1AndMGF1Padding extends OAEPWithMGF1Padding {
+        public OAEPWithSHA1AndMGF1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA1);
+        }
+    }
+
+    public static class OAEPWithSHA224AndMGF1Padding extends OAEPWithMGF1Padding {
+        public OAEPWithSHA224AndMGF1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_224);
+        }
+    }
+
+    public static class OAEPWithSHA256AndMGF1Padding extends OAEPWithMGF1Padding {
+        public OAEPWithSHA256AndMGF1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_256);
+        }
+    }
+
+    public static class OAEPWithSHA384AndMGF1Padding extends OAEPWithMGF1Padding {
+        public OAEPWithSHA384AndMGF1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_384);
+        }
+    }
+
+    public static class OAEPWithSHA512AndMGF1Padding extends OAEPWithMGF1Padding {
+        public OAEPWithSHA512AndMGF1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_512);
+        }
+    }
+
+    private final int mKeymasterPadding;
+    private int mKeymasterPaddingOverride;
+
+    private int mModulusSizeBytes = -1;
+
+    AndroidKeyStoreRSACipherSpi(int keymasterPadding) {
+        mKeymasterPadding = keymasterPadding;
+    }
+
+    @Override
+    protected final void initKey(int opmode, Key key) throws InvalidKeyException {
+        if (key == null) {
+            throw new InvalidKeyException("Unsupported key: null");
+        }
+        if (!KeyProperties.KEY_ALGORITHM_RSA.equalsIgnoreCase(key.getAlgorithm())) {
+            throw new InvalidKeyException("Unsupported key algorithm: " + key.getAlgorithm()
+                    + ". Only " + KeyProperties.KEY_ALGORITHM_RSA + " supported");
+        }
+        AndroidKeyStoreKey keystoreKey;
+        if (key instanceof AndroidKeyStorePrivateKey) {
+            keystoreKey = (AndroidKeyStoreKey) key;
+        } else if (key instanceof AndroidKeyStorePublicKey) {
+            keystoreKey = (AndroidKeyStoreKey) key;
+        } else {
+            throw new InvalidKeyException("Unsupported key type: " + key);
+        }
+
+        if (keystoreKey instanceof PrivateKey) {
+            // Private key
+            switch (opmode) {
+                case Cipher.DECRYPT_MODE:
+                case Cipher.UNWRAP_MODE:
+                    // Permitted
+                    break;
+                case Cipher.ENCRYPT_MODE:
+                case Cipher.WRAP_MODE:
+                    if (!adjustConfigForEncryptingWithPrivateKey()) {
+                        throw new InvalidKeyException(
+                                "RSA private keys cannot be used with " + opmodeToString(opmode)
+                                + " and padding "
+                                + KeyProperties.EncryptionPadding.fromKeymaster(mKeymasterPadding)
+                                + ". Only RSA public keys supported for this mode");
+                    }
+                    break;
+                default:
+                    throw new InvalidKeyException(
+                            "RSA private keys cannot be used with opmode: " + opmode);
+            }
+        } else {
+            // Public key
+            switch (opmode) {
+                case Cipher.ENCRYPT_MODE:
+                case Cipher.WRAP_MODE:
+                    // Permitted
+                    break;
+                case Cipher.DECRYPT_MODE:
+                case Cipher.UNWRAP_MODE:
+                    throw new InvalidKeyException(
+                            "RSA public keys cannot be used with " + opmodeToString(opmode)
+                            + " and padding "
+                            + KeyProperties.EncryptionPadding.fromKeymaster(mKeymasterPadding)
+                            + ". Only RSA private keys supported for this opmode.");
+                    // break;
+                default:
+                    throw new InvalidKeyException(
+                            "RSA public keys cannot be used with " + opmodeToString(opmode));
+            }
+        }
+
+        long keySizeBits = -1;
+        for (Authorization a : keystoreKey.getAuthorizations()) {
+            if (a.keyParameter.tag == KeymasterDefs.KM_TAG_KEY_SIZE) {
+                keySizeBits = KeyStore2ParameterUtils.getUnsignedInt(a);
+            }
+        }
+
+        if (keySizeBits == -1) {
+            throw new InvalidKeyException("Size of key not known");
+        } else if (keySizeBits > Integer.MAX_VALUE) {
+            throw new InvalidKeyException("Key too large: " + keySizeBits + " bits");
+        }
+        mModulusSizeBytes = (int) ((keySizeBits + 7) / 8);
+
+        setKey(keystoreKey);
+    }
+
+    /**
+     * Adjusts the configuration of this cipher for encrypting using the private key.
+     *
+     * <p>The default implementation does nothing and refuses to adjust the configuration.
+     *
+     * @return {@code true} if the configuration has been adjusted, {@code false} if encrypting
+     *         using private key is not permitted for this cipher.
+     */
+    protected boolean adjustConfigForEncryptingWithPrivateKey() {
+        return false;
+    }
+
+    @Override
+    protected final void resetAll() {
+        mModulusSizeBytes = -1;
+        mKeymasterPaddingOverride = -1;
+        super.resetAll();
+    }
+
+    @Override
+    protected final void resetWhilePreservingInitState() {
+        super.resetWhilePreservingInitState();
+    }
+
+    @Override
+    protected void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters) {
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, KeymasterDefs.KM_ALGORITHM_RSA
+        ));
+        int keymasterPadding = getKeymasterPaddingOverride();
+        if (keymasterPadding == -1) {
+            keymasterPadding = mKeymasterPadding;
+        }
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_PADDING, keymasterPadding
+        ));
+        int purposeOverride = getKeymasterPurposeOverride();
+        if ((purposeOverride != -1)
+                && ((purposeOverride == KeymasterDefs.KM_PURPOSE_SIGN)
+                || (purposeOverride == KeymasterDefs.KM_PURPOSE_VERIFY))) {
+            // Keymaster sign/verify requires digest to be specified.
+            // For raw sign/verify it's NONE.
+            parameters.add(KeyStore2ParameterUtils.makeEnum(
+                    KeymasterDefs.KM_TAG_DIGEST, KeymasterDefs.KM_DIGEST_NONE
+            ));
+        }
+    }
+
+    @Override
+    protected void loadAlgorithmSpecificParametersFromBeginResult(
+            KeyParameter[] parameters) {
+    }
+
+    @Override
+    protected final int engineGetBlockSize() {
+        // Not a block cipher, according to the RI
+        return 0;
+    }
+
+    @Override
+    protected final byte[] engineGetIV() {
+        // IV never used
+        return null;
+    }
+
+    @Override
+    protected final int engineGetOutputSize(int inputLen) {
+        return getModulusSizeBytes();
+    }
+
+    protected final int getModulusSizeBytes() {
+        if (mModulusSizeBytes == -1) {
+            throw new IllegalStateException("Not initialized");
+        }
+        return mModulusSizeBytes;
+    }
+
+    /**
+     * Overrides the default padding of the crypto operation.
+     */
+    protected final void setKeymasterPaddingOverride(int keymasterPadding) {
+        mKeymasterPaddingOverride = keymasterPadding;
+    }
+
+    protected final int getKeymasterPaddingOverride() {
+        return mKeymasterPaddingOverride;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreRSAPrivateKey.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.KeyDescriptor;
+
+import java.math.BigInteger;
+import java.security.PrivateKey;
+import java.security.interfaces.RSAKey;
+
+/**
+ * RSA private key (instance of {@link PrivateKey} and {@link RSAKey}) backed by keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreRSAPrivateKey extends AndroidKeyStorePrivateKey implements RSAKey {
+
+    private final BigInteger mModulus;
+
+
+    public AndroidKeyStoreRSAPrivateKey(@NonNull KeyDescriptor descriptor,
+            long keyId,
+            @NonNull Authorization[] authorizations,
+            @NonNull KeyStoreSecurityLevel securityLevel, @NonNull BigInteger modulus) {
+        super(descriptor, keyId, authorizations, KeyProperties.KEY_ALGORITHM_RSA, securityLevel);
+        mModulus = modulus;
+    }
+
+    @Override
+    public BigInteger getModulus() {
+        return mModulus;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreRSAPublicKey.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+
+import java.math.BigInteger;
+import java.security.interfaces.RSAPublicKey;
+
+/**
+ * {@link RSAPublicKey} backed by Android Keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreRSAPublicKey extends AndroidKeyStorePublicKey implements RSAPublicKey {
+    private final BigInteger mModulus;
+    private final BigInteger mPublicExponent;
+
+    public AndroidKeyStoreRSAPublicKey(@NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata,
+            @NonNull KeyStoreSecurityLevel securityLevel, @NonNull BigInteger modulus,
+            @NonNull BigInteger publicExponent) {
+        super(descriptor, metadata, KeyProperties.KEY_ALGORITHM_RSA, securityLevel);
+        mModulus = modulus;
+        mPublicExponent = publicExponent;
+    }
+
+    public AndroidKeyStoreRSAPublicKey(@NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata,
+            @NonNull KeyStoreSecurityLevel securityLevel, @NonNull RSAPublicKey info) {
+        this(descriptor, metadata, securityLevel, info.getModulus(), info.getPublicExponent());
+        if (!"X.509".equalsIgnoreCase(info.getFormat())) {
+            throw new IllegalArgumentException(
+                    "Unsupported key export format: " + info.getFormat());
+        }
+    }
+
+    @Override
+    public AndroidKeyStorePrivateKey getPrivateKey() {
+        return new AndroidKeyStoreRSAPrivateKey(getUserKeyDescriptor(), getKeyIdDescriptor().nspace,
+                getAuthorizations(), getSecurityLevel(), mModulus);
+    }
+
+    @Override
+    public BigInteger getModulus() {
+        return mModulus;
+    }
+
+    @Override
+    public BigInteger getPublicExponent() {
+        return mPublicExponent;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreRSASignatureSpi.java

@@ -0,0 +1,172 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.KeyParameter;
+
+import java.security.InvalidKeyException;
+import java.security.SignatureSpi;
+import java.util.List;
+
+/**
+ * Base class for {@link SignatureSpi} providing Android KeyStore backed RSA signatures.
+ *
+ * @hide
+ */
+abstract class AndroidKeyStoreRSASignatureSpi extends AndroidKeyStoreSignatureSpiBase {
+
+    abstract static class PKCS1Padding extends AndroidKeyStoreRSASignatureSpi {
+        PKCS1Padding(int keymasterDigest) {
+            super(keymasterDigest, KeymasterDefs.KM_PAD_RSA_PKCS1_1_5_SIGN);
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForSign() {
+            // No entropy required for this deterministic signature scheme.
+            return 0;
+        }
+    }
+
+    public static final class NONEWithPKCS1Padding extends PKCS1Padding {
+        public NONEWithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_NONE);
+        }
+    }
+
+    public static final class MD5WithPKCS1Padding extends PKCS1Padding {
+        public MD5WithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_MD5);
+        }
+    }
+
+    public static final class SHA1WithPKCS1Padding extends PKCS1Padding {
+        public SHA1WithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA1);
+        }
+    }
+
+    public static final class SHA224WithPKCS1Padding extends PKCS1Padding {
+        public SHA224WithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_224);
+        }
+    }
+
+    public static final class SHA256WithPKCS1Padding extends PKCS1Padding {
+        public SHA256WithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_256);
+        }
+    }
+
+    public static final class SHA384WithPKCS1Padding extends PKCS1Padding {
+        public SHA384WithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_384);
+        }
+    }
+
+    public static final class SHA512WithPKCS1Padding extends PKCS1Padding {
+        public SHA512WithPKCS1Padding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_512);
+        }
+    }
+
+    abstract static class PSSPadding extends AndroidKeyStoreRSASignatureSpi {
+        private static final int SALT_LENGTH_BYTES = 20;
+
+        PSSPadding(int keymasterDigest) {
+            super(keymasterDigest, KeymasterDefs.KM_PAD_RSA_PSS);
+        }
+
+        @Override
+        protected final int getAdditionalEntropyAmountForSign() {
+            return SALT_LENGTH_BYTES;
+        }
+    }
+
+    public static final class SHA1WithPSSPadding extends PSSPadding {
+        public SHA1WithPSSPadding() {
+            super(KeymasterDefs.KM_DIGEST_SHA1);
+        }
+    }
+
+    public static final class SHA224WithPSSPadding extends PSSPadding {
+        public SHA224WithPSSPadding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_224);
+        }
+    }
+
+    public static final class SHA256WithPSSPadding extends PSSPadding {
+        public SHA256WithPSSPadding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_256);
+        }
+    }
+
+    public static final class SHA384WithPSSPadding extends PSSPadding {
+        public SHA384WithPSSPadding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_384);
+        }
+    }
+
+    public static final class SHA512WithPSSPadding extends PSSPadding {
+        public SHA512WithPSSPadding() {
+            super(KeymasterDefs.KM_DIGEST_SHA_2_512);
+        }
+    }
+
+    private final int mKeymasterDigest;
+    private final int mKeymasterPadding;
+
+    AndroidKeyStoreRSASignatureSpi(int keymasterDigest, int keymasterPadding) {
+        mKeymasterDigest = keymasterDigest;
+        mKeymasterPadding = keymasterPadding;
+    }
+
+    @Override
+    protected final void initKey(AndroidKeyStoreKey key) throws InvalidKeyException {
+        if (!KeyProperties.KEY_ALGORITHM_RSA.equalsIgnoreCase(key.getAlgorithm())) {
+            throw new InvalidKeyException("Unsupported key algorithm: " + key.getAlgorithm()
+                    + ". Only" + KeyProperties.KEY_ALGORITHM_RSA + " supported");
+        }
+        super.initKey(key);
+    }
+
+    @Override
+    protected final void resetAll() {
+        super.resetAll();
+    }
+
+    @Override
+    protected final void resetWhilePreservingInitState() {
+        super.resetWhilePreservingInitState();
+    }
+
+    @Override
+    protected final void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters) {
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, KeymasterDefs.KM_ALGORITHM_RSA
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_DIGEST, mKeymasterDigest
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_PADDING, mKeymasterPadding
+        ));
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreSecretKey.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreSecurityLevel;
+import android.system.keystore2.KeyDescriptor;
+import android.system.keystore2.KeyMetadata;
+
+import javax.crypto.SecretKey;
+
+/**
+ * {@link SecretKey} backed by Android Keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreSecretKey extends AndroidKeyStoreKey implements SecretKey {
+
+    public AndroidKeyStoreSecretKey(@NonNull KeyDescriptor descriptor,
+            @NonNull KeyMetadata metadata, @NonNull String algorithm,
+            @NonNull KeyStoreSecurityLevel securityLevel) {
+        super(descriptor, metadata.key.nspace, metadata.authorizations, algorithm, securityLevel);
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreSecretKeyFactorySpi.java

@@ -0,0 +1,272 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.GateKeeper;
+import android.security.KeyStore;
+import android.security.keymaster.KeymasterArguments;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyGenParameterSpec;
+import android.security.keystore.KeyInfo;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.Authorization;
+
+import java.math.BigInteger;
+import java.security.InvalidKeyException;
+import java.security.ProviderException;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.KeySpec;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+
+import javax.crypto.SecretKey;
+import javax.crypto.SecretKeyFactorySpi;
+import javax.crypto.spec.SecretKeySpec;
+
+/**
+ * {@link SecretKeyFactorySpi} backed by Android Keystore.
+ *
+ * @hide
+ */
+public class AndroidKeyStoreSecretKeyFactorySpi extends SecretKeyFactorySpi {
+
+    private final KeyStore mKeyStore = KeyStore.getInstance();
+
+    @Override
+    protected KeySpec engineGetKeySpec(SecretKey key,
+            @SuppressWarnings("rawtypes") Class keySpecClass) throws InvalidKeySpecException {
+        if (keySpecClass == null) {
+            throw new InvalidKeySpecException("keySpecClass == null");
+        }
+        if (!(key instanceof AndroidKeyStoreSecretKey)) {
+            throw new InvalidKeySpecException("Only Android KeyStore secret keys supported: " +
+                    ((key != null) ? key.getClass().getName() : "null"));
+        }
+        if (SecretKeySpec.class.isAssignableFrom(keySpecClass)) {
+            throw new InvalidKeySpecException(
+                    "Key material export of Android KeyStore keys is not supported");
+        }
+        if (!KeyInfo.class.equals(keySpecClass)) {
+            throw new InvalidKeySpecException("Unsupported key spec: " + keySpecClass.getName());
+        }
+        AndroidKeyStoreKey keystoreKey = (AndroidKeyStoreKey) key;
+
+        return getKeyInfo(keystoreKey);
+    }
+
+    static @NonNull KeyInfo getKeyInfo(@NonNull AndroidKeyStoreKey key) {
+
+        @KeyProperties.SecurityLevelEnum int securityLevel =
+                KeyProperties.SECURITY_LEVEL_SOFTWARE;
+        boolean insideSecureHardware = false;
+        @KeyProperties.OriginEnum int origin = -1;
+        int keySize = -1;
+        @KeyProperties.PurposeEnum int purposes = 0;
+        String[] encryptionPaddings;
+        String[] signaturePaddings;
+        List<String> digestsList = new ArrayList<>();
+        List<String> blockModesList = new ArrayList<>();
+        int keymasterSwEnforcedUserAuthenticators = 0;
+        int keymasterHwEnforcedUserAuthenticators = 0;
+        List<BigInteger> keymasterSecureUserIds = new ArrayList<BigInteger>();
+        List<String> encryptionPaddingsList = new ArrayList<String>();
+        List<String> signaturePaddingsList = new ArrayList<String>();
+        Date keyValidityStart = null;
+        Date keyValidityForOriginationEnd = null;
+        Date keyValidityForConsumptionEnd = null;
+        long userAuthenticationValidityDurationSeconds = 0;
+        boolean userAuthenticationRequired = true;
+        boolean userAuthenticationValidWhileOnBody = false;
+        boolean trustedUserPresenceRequired = false;
+        boolean trustedUserConfirmationRequired = false;
+        try {
+            for (Authorization a : key.getAuthorizations()) {
+                switch (a.keyParameter.tag) {
+                    case KeymasterDefs.KM_TAG_ORIGIN:
+                        insideSecureHardware =
+                                KeyStore2ParameterUtils.isSecureHardware(a.securityLevel);
+                        securityLevel = a.securityLevel;
+                        origin = KeyProperties.Origin.fromKeymaster(a.keyParameter.integer);
+                        break;
+                    case KeymasterDefs.KM_TAG_KEY_SIZE:
+                        long keySizeUnsigned = KeyStore2ParameterUtils.getUnsignedInt(a);
+                        if (keySizeUnsigned > Integer.MAX_VALUE) {
+                            throw new ProviderException(
+                                    "Key too large: " + keySizeUnsigned + " bits");
+                        }
+                        keySize = (int) keySizeUnsigned;
+                        break;
+                    case KeymasterDefs.KM_TAG_PURPOSE:
+                        purposes |= KeyProperties.Purpose.fromKeymaster(a.keyParameter.integer);
+                        break;
+                    case KeymasterDefs.KM_TAG_PADDING:
+                        try {
+                            if (a.keyParameter.integer == KeymasterDefs.KM_PAD_RSA_PKCS1_1_5_SIGN
+                                    || a.keyParameter.integer == KeymasterDefs.KM_PAD_RSA_PSS) {
+                                @KeyProperties.SignaturePaddingEnum String padding =
+                                        KeyProperties.SignaturePadding.fromKeymaster(
+                                                a.keyParameter.integer);
+                                signaturePaddingsList.add(padding);
+                            } else {
+                                @KeyProperties.EncryptionPaddingEnum String jcaPadding =
+                                        KeyProperties.EncryptionPadding.fromKeymaster(
+                                                a.keyParameter.integer);
+                                encryptionPaddingsList.add(jcaPadding);
+                            }
+                        } catch (IllegalArgumentException e) {
+                            throw new ProviderException("Unsupported padding: "
+                                                + a.keyParameter.integer);
+                        }
+                        break;
+                    case KeymasterDefs.KM_TAG_DIGEST:
+                        digestsList.add(KeyProperties.Digest.fromKeymaster(a.keyParameter.integer));
+                        break;
+                    case KeymasterDefs.KM_TAG_BLOCK_MODE:
+                        blockModesList.add(
+                                KeyProperties.BlockMode.fromKeymaster(a.keyParameter.integer)
+                        );
+                        break;
+                    case KeymasterDefs.KM_TAG_USER_AUTH_TYPE:
+                        if (KeyStore2ParameterUtils.isSecureHardware(a.securityLevel)) {
+                            keymasterHwEnforcedUserAuthenticators = a.keyParameter.integer;
+                        } else {
+                            keymasterSwEnforcedUserAuthenticators = a.keyParameter.integer;
+                        }
+                        break;
+                    case KeymasterDefs.KM_TAG_USER_SECURE_ID:
+                        keymasterSecureUserIds.add(
+                                KeymasterArguments.toUint64(a.keyParameter.longInteger));
+                        break;
+                    case KeymasterDefs.KM_TAG_ACTIVE_DATETIME:
+                        keyValidityStart = KeyStore2ParameterUtils.getDate(a);
+                        break;
+                    case KeymasterDefs.KM_TAG_ORIGINATION_EXPIRE_DATETIME:
+                        keyValidityForOriginationEnd =
+                                KeyStore2ParameterUtils.getDate(a);
+                        break;
+                    case KeymasterDefs.KM_TAG_USAGE_EXPIRE_DATETIME:
+                        keyValidityForConsumptionEnd =
+                                KeyStore2ParameterUtils.getDate(a);
+                        break;
+                    case KeymasterDefs.KM_TAG_NO_AUTH_REQUIRED:
+                        userAuthenticationRequired = false;
+                        break;
+                    case KeymasterDefs.KM_TAG_AUTH_TIMEOUT:
+                        userAuthenticationValidityDurationSeconds =
+                                KeyStore2ParameterUtils.getUnsignedInt(a);
+                        if (userAuthenticationValidityDurationSeconds > Integer.MAX_VALUE) {
+                            throw new ProviderException(
+                                    "User authentication timeout validity too long: "
+                                    + userAuthenticationValidityDurationSeconds + " seconds");
+                        }
+                        break;
+                    case KeymasterDefs.KM_TAG_ALLOW_WHILE_ON_BODY:
+                        userAuthenticationValidWhileOnBody =
+                                KeyStore2ParameterUtils.isSecureHardware(a.securityLevel);
+                        break;
+                    case KeymasterDefs.KM_TAG_TRUSTED_USER_PRESENCE_REQUIRED:
+                        trustedUserPresenceRequired =
+                                KeyStore2ParameterUtils.isSecureHardware(a.securityLevel);
+                        break;
+                    case KeymasterDefs.KM_TAG_TRUSTED_CONFIRMATION_REQUIRED:
+                        trustedUserConfirmationRequired =
+                                KeyStore2ParameterUtils.isSecureHardware(a.securityLevel);
+                        break;
+                }
+            }
+        } catch (IllegalArgumentException e) {
+            throw new ProviderException("Unsupported key characteristic", e);
+        }
+        if (keySize == -1) {
+            throw new ProviderException("Key size not available");
+        }
+        if (origin == -1) {
+            throw new ProviderException("Key origin not available");
+        }
+
+        encryptionPaddings =
+                encryptionPaddingsList.toArray(new String[0]);
+        signaturePaddings =
+                signaturePaddingsList.toArray(new String[0]);
+
+        boolean userAuthenticationRequirementEnforcedBySecureHardware = (userAuthenticationRequired)
+                && (keymasterHwEnforcedUserAuthenticators != 0)
+                && (keymasterSwEnforcedUserAuthenticators == 0);
+
+        String[] digests = digestsList.toArray(new String[0]);
+        String[] blockModes = blockModesList.toArray(new String[0]);
+
+        boolean invalidatedByBiometricEnrollment = false;
+        if (keymasterSwEnforcedUserAuthenticators == KeymasterDefs.HW_AUTH_BIOMETRIC
+            || keymasterHwEnforcedUserAuthenticators == KeymasterDefs.HW_AUTH_BIOMETRIC) {
+            // Fingerprint-only key; will be invalidated if the root SID isn't in the SID list.
+            invalidatedByBiometricEnrollment = !keymasterSecureUserIds.isEmpty()
+                    && !keymasterSecureUserIds.contains(getGateKeeperSecureUserId());
+        }
+
+        return new KeyInfo(key.getUserKeyDescriptor().alias,
+                insideSecureHardware,
+                origin,
+                keySize,
+                keyValidityStart,
+                keyValidityForOriginationEnd,
+                keyValidityForConsumptionEnd,
+                purposes,
+                encryptionPaddings,
+                signaturePaddings,
+                digests,
+                blockModes,
+                userAuthenticationRequired,
+                (int) userAuthenticationValidityDurationSeconds,
+                keymasterHwEnforcedUserAuthenticators,
+                userAuthenticationRequirementEnforcedBySecureHardware,
+                userAuthenticationValidWhileOnBody,
+                trustedUserPresenceRequired,
+                invalidatedByBiometricEnrollment,
+                trustedUserConfirmationRequired,
+                securityLevel);
+    }
+
+    private static BigInteger getGateKeeperSecureUserId() throws ProviderException {
+    	try {
+    		return BigInteger.valueOf(GateKeeper.getSecureUserId());
+    	} catch (IllegalStateException e) {
+    		throw new ProviderException("Failed to get GateKeeper secure user ID", e);
+    	}
+    }
+
+    @Override
+    protected SecretKey engineGenerateSecret(KeySpec keySpec) throws InvalidKeySpecException {
+        throw new InvalidKeySpecException(
+                "To generate secret key in Android Keystore, use KeyGenerator initialized with "
+                        + KeyGenParameterSpec.class.getName());
+    }
+
+    @Override
+    protected SecretKey engineTranslateKey(SecretKey key) throws InvalidKeyException {
+        if (key == null) {
+            throw new InvalidKeyException("key == null");
+        } else if (!(key instanceof AndroidKeyStoreSecretKey)) {
+            throw new InvalidKeyException(
+                    "To import a secret key into Android Keystore, use KeyStore.setEntry");
+        }
+
+        return key;
+    }
+}

keystore/java/android/security/keystore2/AndroidKeyStoreSignatureSpiBase.java

@@ -0,0 +1,423 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.CallSuper;
+import android.annotation.NonNull;
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+import android.security.keystore.KeyStoreCryptoOperation;
+import android.system.keystore2.KeyParameter;
+
+import libcore.util.EmptyArray;
+
+import java.nio.ByteBuffer;
+import java.security.InvalidKeyException;
+import java.security.InvalidParameterException;
+import java.security.PrivateKey;
+import java.security.ProviderException;
+import java.security.PublicKey;
+import java.security.SecureRandom;
+import java.security.SignatureException;
+import java.security.SignatureSpi;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Base class for {@link SignatureSpi} implementations of Android KeyStore backed ciphers.
+ *
+ * @hide
+ */
+abstract class AndroidKeyStoreSignatureSpiBase extends SignatureSpi
+        implements KeyStoreCryptoOperation {
+    private static final String TAG = "AndroidKeyStoreSignatureSpiBase";
+
+    // Fields below are populated by SignatureSpi.engineInitSign/engineInitVerify and KeyStore.begin
+    // and should be preserved after SignatureSpi.engineSign/engineVerify finishes.
+    private boolean mSigning;
+    private AndroidKeyStoreKey mKey;
+
+    /**
+     * Object representing this operation inside keystore service. It is initialized
+     * by {@code engineInit} and is invalidated when {@code engineDoFinal} succeeds and on some
+     * error conditions in between.
+     */
+    private KeyStoreOperation mOperation;
+    /**
+     * The operation challenge is required when an operation needs user authorization.
+     * The challenge is subjected to an authenticator, e.g., Gatekeeper or a biometric
+     * authenticator, and included in the authentication token minted by this authenticator.
+     * It may be null, if the operation does not require authorization.
+     */
+    private long mOperationChallenge;
+    private KeyStoreCryptoOperationStreamer mMessageStreamer;
+
+    /**
+     * Encountered exception which could not be immediately thrown because it was encountered inside
+     * a method that does not throw checked exception. This exception will be thrown from
+     * {@code engineSign} or {@code engineVerify}. Once such an exception is encountered,
+     * {@code engineUpdate} starts ignoring input data.
+     */
+    private Exception mCachedException;
+
+    AndroidKeyStoreSignatureSpiBase() {
+        mOperation = null;
+        mOperationChallenge = 0;
+        mSigning = false;
+        mKey = null;
+        appRandom = null;
+        mMessageStreamer = null;
+        mCachedException = null;
+    }
+
+    @Override
+    protected final void engineInitSign(PrivateKey key) throws InvalidKeyException {
+        engineInitSign(key, null);
+    }
+
+    @Override
+    protected final void engineInitSign(PrivateKey privateKey, SecureRandom random)
+            throws InvalidKeyException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            if (privateKey == null) {
+                throw new InvalidKeyException("Unsupported key: null");
+            }
+            AndroidKeyStoreKey keystoreKey;
+            if (privateKey instanceof AndroidKeyStorePrivateKey) {
+                keystoreKey = (AndroidKeyStoreKey) privateKey;
+            } else {
+                throw new InvalidKeyException("Unsupported private key type: " + privateKey);
+            }
+            mSigning = true;
+            initKey(keystoreKey);
+            appRandom = random;
+            ensureKeystoreOperationInitialized();
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    @Override
+    protected final void engineInitVerify(PublicKey publicKey) throws InvalidKeyException {
+        resetAll();
+
+        boolean success = false;
+        try {
+            if (publicKey == null) {
+                throw new InvalidKeyException("Unsupported key: null");
+            }
+            AndroidKeyStoreKey keystoreKey;
+            if (publicKey instanceof AndroidKeyStorePublicKey) {
+                keystoreKey = (AndroidKeyStorePublicKey) publicKey;
+            } else {
+                throw new InvalidKeyException("Unsupported public key type: " + publicKey);
+            }
+            mSigning = false;
+            initKey(keystoreKey);
+            appRandom = null;
+            ensureKeystoreOperationInitialized();
+            success = true;
+        } finally {
+            if (!success) {
+                resetAll();
+            }
+        }
+    }
+
+    /**
+     * Configures this signature instance to use the provided key.
+     *
+     * @throws InvalidKeyException if the {@code key} is not suitable.
+     */
+    @CallSuper
+    protected void initKey(AndroidKeyStoreKey key) throws InvalidKeyException {
+        mKey = key;
+    }
+
+    private void abortOperation() {
+        KeyStoreCryptoOperationUtils.abortOperation(mOperation);
+        mOperation = null;
+    }
+
+    /**
+     * Resets this cipher to its pristine pre-init state. This must be equivalent to obtaining a new
+     * cipher instance.
+     *
+     * <p>Subclasses storing additional state should override this method, reset the additional
+     * state, and then chain to superclass.
+     */
+    @CallSuper
+    protected void resetAll() {
+        abortOperation();
+        mOperationChallenge = 0;
+        mSigning = false;
+        mKey = null;
+        appRandom = null;
+        mMessageStreamer = null;
+        mCachedException = null;
+    }
+
+    /**
+     * Resets this cipher while preserving the initialized state. This must be equivalent to
+     * rolling back the cipher's state to just after the most recent {@code engineInit} completed
+     * successfully.
+     *
+     * <p>Subclasses storing additional post-init state should override this method, reset the
+     * additional state, and then chain to superclass.
+     */
+    @CallSuper
+    protected void resetWhilePreservingInitState() {
+        abortOperation();
+        mOperationChallenge = 0;
+        mMessageStreamer = null;
+        mCachedException = null;
+    }
+
+    private void ensureKeystoreOperationInitialized() throws InvalidKeyException {
+        if (mMessageStreamer != null) {
+            return;
+        }
+        if (mCachedException != null) {
+            return;
+        }
+        if (mKey == null) {
+            throw new IllegalStateException("Not initialized");
+        }
+
+        List<KeyParameter> parameters = new ArrayList<>();
+        addAlgorithmSpecificParametersToBegin(parameters);
+
+        int purpose = mSigning ? KeymasterDefs.KM_PURPOSE_SIGN : KeymasterDefs.KM_PURPOSE_VERIFY;
+
+        parameters.add(KeyStore2ParameterUtils.makeEnum(KeymasterDefs.KM_TAG_PURPOSE, purpose));
+
+        try {
+            mOperation = mKey.getSecurityLevel().createOperation(
+                    mKey.getKeyIdDescriptor(),
+                    parameters);
+        } catch (KeyStoreException keyStoreException) {
+            throw KeyStoreCryptoOperationUtils.getInvalidKeyException(
+                    mKey, keyStoreException);
+        }
+
+        // Now we check if we got an operation challenge. This indicates that user authorization
+        // is required. And if we got a challenge we check if the authorization can possibly
+        // succeed.
+        mOperationChallenge = KeyStoreCryptoOperationUtils.getOrMakeOperationChallenge(
+                mOperation, mKey);
+
+        mMessageStreamer = createMainDataStreamer(mOperation);
+    }
+
+    /**
+     * Creates a streamer which sends the message to be signed/verified into the provided KeyStore
+     *
+     * <p>This implementation returns a working streamer.
+     */
+    @NonNull
+    protected KeyStoreCryptoOperationStreamer createMainDataStreamer(
+            @NonNull KeyStoreOperation operation) {
+        return new KeyStoreCryptoOperationChunkedStreamer(
+                new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(
+                        operation));
+    }
+
+    @Override
+    public final long getOperationHandle() {
+        return mOperationChallenge;
+    }
+
+    @Override
+    protected final void engineUpdate(byte[] b, int off, int len) throws SignatureException {
+        if (mCachedException != null) {
+            throw new SignatureException(mCachedException);
+        }
+
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException e) {
+            throw new SignatureException(e);
+        }
+
+        if (len == 0) {
+            return;
+        }
+
+        byte[] output;
+        try {
+            output = mMessageStreamer.update(b, off, len);
+        } catch (KeyStoreException e) {
+            throw new SignatureException(e);
+        }
+
+        if (output.length != 0) {
+            throw new ProviderException(
+                    "Update operation unexpectedly produced output: " + output.length + " bytes");
+        }
+    }
+
+    @Override
+    protected final void engineUpdate(byte b) throws SignatureException {
+        engineUpdate(new byte[] {b}, 0, 1);
+    }
+
+    @Override
+    protected final void engineUpdate(ByteBuffer input) {
+        byte[] b;
+        int off;
+        int len = input.remaining();
+        if (input.hasArray()) {
+            b = input.array();
+            off = input.arrayOffset() + input.position();
+            input.position(input.limit());
+        } else {
+            b = new byte[len];
+            off = 0;
+            input.get(b);
+        }
+
+        try {
+            engineUpdate(b, off, len);
+        } catch (SignatureException e) {
+            mCachedException = e;
+        }
+    }
+
+    @Override
+    protected final int engineSign(byte[] out, int outOffset, int outLen)
+            throws SignatureException {
+        return super.engineSign(out, outOffset, outLen);
+    }
+
+    @Override
+    protected final byte[] engineSign() throws SignatureException {
+        if (mCachedException != null) {
+            throw new SignatureException(mCachedException);
+        }
+
+        byte[] signature;
+        try {
+            ensureKeystoreOperationInitialized();
+
+            byte[] additionalEntropy =
+                    KeyStoreCryptoOperationUtils.getRandomBytesToMixIntoKeystoreRng(
+                            appRandom, getAdditionalEntropyAmountForSign());
+            signature = mMessageStreamer.doFinal(
+                    EmptyArray.BYTE, 0, 0,
+                    null); // no signature provided -- it'll be generated by this invocation
+        } catch (InvalidKeyException | KeyStoreException e) {
+            throw new SignatureException(e);
+        }
+
+        resetWhilePreservingInitState();
+        return signature;
+    }
+
+    @Override
+    protected final boolean engineVerify(byte[] signature) throws SignatureException {
+        if (mCachedException != null) {
+            throw new SignatureException(mCachedException);
+        }
+
+        try {
+            ensureKeystoreOperationInitialized();
+        } catch (InvalidKeyException e) {
+            throw new SignatureException(e);
+        }
+
+        boolean verified;
+        try {
+            byte[] output = mMessageStreamer.doFinal(
+                    EmptyArray.BYTE, 0, 0,
+                    signature);
+            if (output.length != 0) {
+                throw new ProviderException(
+                        "Signature verification unexpected produced output: " + output.length
+                        + " bytes");
+            }
+            verified = true;
+        } catch (KeyStoreException e) {
+            switch (e.getErrorCode()) {
+                case KeymasterDefs.KM_ERROR_VERIFICATION_FAILED:
+                    verified = false;
+                    break;
+                default:
+                    throw new SignatureException(e);
+            }
+        }
+
+        resetWhilePreservingInitState();
+        return verified;
+    }
+
+    @Override
+    protected final boolean engineVerify(byte[] sigBytes, int offset, int len)
+            throws SignatureException {
+        return engineVerify(ArrayUtils.subarray(sigBytes, offset, len));
+    }
+
+    @Deprecated
+    @Override
+    protected final Object engineGetParameter(String param) throws InvalidParameterException {
+        throw new InvalidParameterException();
+    }
+
+    @Deprecated
+    @Override
+    protected final void engineSetParameter(String param, Object value)
+            throws InvalidParameterException {
+        throw new InvalidParameterException();
+    }
+
+    /**
+     * Returns {@code true} if this signature is initialized for signing, {@code false} if this
+     * signature is initialized for verification.
+     */
+    protected final boolean isSigning() {
+        return mSigning;
+    }
+
+    // The methods below need to be implemented by subclasses.
+
+    /**
+     * Returns the amount of additional entropy (in bytes) to be provided to the KeyStore's
+     * {@code finish} operation when generating a signature.
+     *
+     * <p>This value should match (or exceed) the amount of Shannon entropy of the produced
+     * signature assuming the key and the message are known. For example, for ECDSA signature this
+     * should be the size of {@code R}, whereas for the RSA signature with PKCS#1 padding this
+     * should be {@code 0}.
+     */
+    protected abstract int getAdditionalEntropyAmountForSign();
+
+    /**
+     * Invoked to add algorithm-specific parameters for the KeyStore's {@code begin} operation.
+     *
+     * @param parameters keystore/keymaster arguments to be populated with algorithm-specific
+     *        parameters.
+     */
+    protected abstract void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters);
+}

keystore/java/android/security/keystore2/AndroidKeyStoreUnauthenticatedAESCipherSpi.java

@@ -0,0 +1,335 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+import android.security.keystore.KeyProperties;
+import android.system.keystore2.KeyParameter;
+
+import java.security.AlgorithmParameters;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.Key;
+import java.security.NoSuchAlgorithmException;
+import java.security.ProviderException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidParameterSpecException;
+import java.util.Arrays;
+import java.util.List;
+
+import javax.crypto.CipherSpi;
+import javax.crypto.spec.IvParameterSpec;
+
+/**
+ * Base class for Android Keystore unauthenticated AES {@link CipherSpi} implementations.
+ *
+ * @hide
+ */
+class AndroidKeyStoreUnauthenticatedAESCipherSpi extends AndroidKeyStoreCipherSpiBase {
+
+    abstract static class ECB extends AndroidKeyStoreUnauthenticatedAESCipherSpi {
+        protected ECB(int keymasterPadding) {
+            super(KeymasterDefs.KM_MODE_ECB, keymasterPadding, false);
+        }
+
+        public static class NoPadding extends ECB {
+            public NoPadding() {
+                super(KeymasterDefs.KM_PAD_NONE);
+            }
+        }
+
+        public static class PKCS7Padding extends ECB {
+            public PKCS7Padding() {
+                super(KeymasterDefs.KM_PAD_PKCS7);
+            }
+        }
+    }
+
+    abstract static class CBC extends AndroidKeyStoreUnauthenticatedAESCipherSpi {
+        protected CBC(int keymasterPadding) {
+            super(KeymasterDefs.KM_MODE_CBC, keymasterPadding, true);
+        }
+
+        public static class NoPadding extends CBC {
+            public NoPadding() {
+                super(KeymasterDefs.KM_PAD_NONE);
+            }
+        }
+
+        public static class PKCS7Padding extends CBC {
+            public PKCS7Padding() {
+                super(KeymasterDefs.KM_PAD_PKCS7);
+            }
+        }
+    }
+
+    abstract static class CTR extends AndroidKeyStoreUnauthenticatedAESCipherSpi {
+        protected CTR(int keymasterPadding) {
+            super(KeymasterDefs.KM_MODE_CTR, keymasterPadding, true);
+        }
+
+        public static class NoPadding extends CTR {
+            public NoPadding() {
+                super(KeymasterDefs.KM_PAD_NONE);
+            }
+        }
+    }
+
+    private static final int BLOCK_SIZE_BYTES = 16;
+
+    private final int mKeymasterBlockMode;
+    private final int mKeymasterPadding;
+    /** Whether this transformation requires an IV. */
+    private final boolean mIvRequired;
+
+    private byte[] mIv;
+
+    /** Whether the current {@code #mIv} has been used by the underlying crypto operation. */
+    private boolean mIvHasBeenUsed;
+
+    AndroidKeyStoreUnauthenticatedAESCipherSpi(
+            int keymasterBlockMode,
+            int keymasterPadding,
+            boolean ivRequired) {
+        mKeymasterBlockMode = keymasterBlockMode;
+        mKeymasterPadding = keymasterPadding;
+        mIvRequired = ivRequired;
+    }
+
+    @Override
+    protected final void resetAll() {
+        mIv = null;
+        mIvHasBeenUsed = false;
+        super.resetAll();
+    }
+
+    @Override
+    protected final void resetWhilePreservingInitState() {
+        super.resetWhilePreservingInitState();
+    }
+
+    @Override
+    protected final void initKey(int opmode, Key key) throws InvalidKeyException {
+        if (!(key instanceof AndroidKeyStoreSecretKey)) {
+            throw new InvalidKeyException(
+                    "Unsupported key: " + ((key != null) ? key.getClass().getName() : "null"));
+        }
+        if (!KeyProperties.KEY_ALGORITHM_AES.equalsIgnoreCase(key.getAlgorithm())) {
+            throw new InvalidKeyException(
+                    "Unsupported key algorithm: " + key.getAlgorithm() + ". Only " +
+                    KeyProperties.KEY_ALGORITHM_AES + " supported");
+        }
+        setKey((AndroidKeyStoreSecretKey) key);
+    }
+
+    @Override
+    protected final void initAlgorithmSpecificParameters() throws InvalidKeyException {
+        if (!mIvRequired) {
+            return;
+        }
+
+        // IV is used
+        if (!isEncrypting()) {
+            throw new InvalidKeyException("IV required when decrypting"
+                    + ". Use IvParameterSpec or AlgorithmParameters to provide it.");
+        }
+    }
+
+    @Override
+    protected final void initAlgorithmSpecificParameters(AlgorithmParameterSpec params)
+            throws InvalidAlgorithmParameterException {
+        if (!mIvRequired) {
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);
+            }
+            return;
+        }
+
+        // IV is used
+        if (params == null) {
+            if (!isEncrypting()) {
+                // IV must be provided by the caller
+                throw new InvalidAlgorithmParameterException(
+                        "IvParameterSpec must be provided when decrypting");
+            }
+            return;
+        }
+        if (!(params instanceof IvParameterSpec)) {
+            throw new InvalidAlgorithmParameterException("Only IvParameterSpec supported");
+        }
+        mIv = ((IvParameterSpec) params).getIV();
+        if (mIv == null) {
+            throw new InvalidAlgorithmParameterException("Null IV in IvParameterSpec");
+        }
+    }
+
+    @Override
+    protected final void initAlgorithmSpecificParameters(AlgorithmParameters params)
+            throws InvalidAlgorithmParameterException {
+        if (!mIvRequired) {
+            if (params != null) {
+                throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);
+            }
+            return;
+        }
+
+        // IV is used
+        if (params == null) {
+            if (!isEncrypting()) {
+                // IV must be provided by the caller
+                throw new InvalidAlgorithmParameterException("IV required when decrypting"
+                        + ". Use IvParameterSpec or AlgorithmParameters to provide it.");
+            }
+            return;
+        }
+
+        if (!"AES".equalsIgnoreCase(params.getAlgorithm())) {
+            throw new InvalidAlgorithmParameterException(
+                    "Unsupported AlgorithmParameters algorithm: " + params.getAlgorithm()
+                    + ". Supported: AES");
+        }
+
+        IvParameterSpec ivSpec;
+        try {
+            ivSpec = params.getParameterSpec(IvParameterSpec.class);
+        } catch (InvalidParameterSpecException e) {
+            if (!isEncrypting()) {
+                // IV must be provided by the caller
+                throw new InvalidAlgorithmParameterException("IV required when decrypting"
+                        + ", but not found in parameters: " + params, e);
+            }
+            mIv = null;
+            return;
+        }
+        mIv = ivSpec.getIV();
+        if (mIv == null) {
+            throw new InvalidAlgorithmParameterException("Null IV in AlgorithmParameters");
+        }
+    }
+
+    @Override
+    protected final int getAdditionalEntropyAmountForBegin() {
+        if ((mIvRequired) && (mIv == null) && (isEncrypting())) {
+            // IV will need to be generated
+            return BLOCK_SIZE_BYTES;
+        }
+
+        return 0;
+    }
+
+    @Override
+    protected final int getAdditionalEntropyAmountForFinish() {
+        return 0;
+    }
+
+    @Override
+    protected final void addAlgorithmSpecificParametersToBegin(
+            @NonNull List<KeyParameter> parameters) {
+        if ((isEncrypting()) && (mIvRequired) && (mIvHasBeenUsed)) {
+            // IV is being reused for encryption: this violates security best practices.
+            throw new IllegalStateException(
+                    "IV has already been used. Reusing IV in encryption mode violates security best"
+                    + " practices.");
+        }
+
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_ALGORITHM, KeymasterDefs.KM_ALGORITHM_AES
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_BLOCK_MODE, mKeymasterBlockMode
+        ));
+        parameters.add(KeyStore2ParameterUtils.makeEnum(
+                KeymasterDefs.KM_TAG_PADDING, mKeymasterPadding
+        ));
+        if ((mIvRequired) && (mIv != null)) {
+            parameters.add(KeyStore2ParameterUtils.makeBytes(
+                    KeymasterDefs.KM_TAG_NONCE, mIv
+            ));
+        }
+    }
+
+    @Override
+    protected final void loadAlgorithmSpecificParametersFromBeginResult(
+            KeyParameter[] parameters) {
+        mIvHasBeenUsed = true;
+
+        // NOTE: Keymaster doesn't always return an IV, even if it's used.
+        byte[] returnedIv = null;
+        if (parameters != null) {
+            for (KeyParameter p : parameters) {
+                if (p.tag == KeymasterDefs.KM_TAG_NONCE) {
+                    returnedIv = p.blob;
+                    break;
+                }
+            }
+        }
+
+        if (mIvRequired) {
+            if (mIv == null) {
+                mIv = returnedIv;
+            } else if ((returnedIv != null) && (!Arrays.equals(returnedIv, mIv))) {
+                throw new ProviderException("IV in use differs from provided IV");
+            }
+        } else {
+            if (returnedIv != null) {
+                throw new ProviderException(
+                        "IV in use despite IV not being used by this transformation");
+            }
+        }
+    }
+
+    @Override
+    protected final int engineGetBlockSize() {
+        return BLOCK_SIZE_BYTES;
+    }
+
+    @Override
+    protected final int engineGetOutputSize(int inputLen) {
+        return inputLen + 3 * BLOCK_SIZE_BYTES;
+    }
+
+    @Override
+    protected final byte[] engineGetIV() {
+        return ArrayUtils.cloneIfNotEmpty(mIv);
+    }
+
+    @Nullable
+    @Override
+    protected final AlgorithmParameters engineGetParameters() {
+        if (!mIvRequired) {
+            return null;
+        }
+        if ((mIv != null) && (mIv.length > 0)) {
+            try {
+                AlgorithmParameters params = AlgorithmParameters.getInstance("AES");
+                params.init(new IvParameterSpec(mIv));
+                return params;
+            } catch (NoSuchAlgorithmException e) {
+                throw new ProviderException(
+                        "Failed to obtain AES AlgorithmParameters", e);
+            } catch (InvalidParameterSpecException e) {
+                throw new ProviderException(
+                        "Failed to initialize AES AlgorithmParameters with an IV",
+                        e);
+            }
+        }
+        return null;
+    }
+}

keystore/java/android/security/keystore2/KeyStore2ParameterUtils.java

@@ -0,0 +1,313 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.hardware.biometrics.BiometricManager;
+import android.security.GateKeeper;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyProperties;
+import android.security.keystore.UserAuthArgs;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.KeyParameter;
+import android.system.keystore2.SecurityLevel;
+
+import java.security.ProviderException;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.function.Consumer;
+
+/**
+ * @hide
+ */
+public abstract class KeyStore2ParameterUtils {
+
+    /**
+     * This function constructs a {@link KeyParameter} expressing a boolean value.
+     * @param tag Must be KeyMint tag with the associated type BOOL.
+     * @return An instance of {@link KeyParameter}.
+     * @hide
+     */
+    static @NonNull KeyParameter makeBool(int tag) {
+        int type = KeymasterDefs.getTagType(tag);
+        if (type != KeymasterDefs.KM_BOOL) {
+            throw new IllegalArgumentException("Not a boolean tag: " + tag);
+        }
+        KeyParameter p = new KeyParameter();
+        p.tag = tag;
+        p.boolValue = true;
+        return p;
+    }
+
+    /**
+     * This function constructs a {@link KeyParameter} expressing an enum value.
+     * @param tag Must be KeyMint tag with the associated type ENUM or ENUM_REP.
+     * @param v A 32bit integer.
+     * @return An instance of {@link KeyParameter}.
+     * @hide
+     */
+    static @NonNull KeyParameter makeEnum(int tag, int v) {
+        int type = KeymasterDefs.getTagType(tag);
+        if (type != KeymasterDefs.KM_ENUM && type != KeymasterDefs.KM_ENUM_REP) {
+            throw new IllegalArgumentException("Not an enum or repeatable enum tag: " + tag);
+        }
+        KeyParameter p = new KeyParameter();
+        p.tag = tag;
+        p.integer = v;
+        return p;
+    }
+
+    /**
+     * This function constructs a {@link KeyParameter} expressing an integer value.
+     * @param tag Must be KeyMint tag with the associated type UINT or UINT_REP.
+     * @param v A 32bit integer.
+     * @return An instance of {@link KeyParameter}.
+     * @hide
+     */
+    static @NonNull KeyParameter makeInt(int tag, int v) {
+        int type = KeymasterDefs.getTagType(tag);
+        if (type != KeymasterDefs.KM_UINT && type != KeymasterDefs.KM_UINT_REP) {
+            throw new IllegalArgumentException("Not an int or repeatable int tag: " + tag);
+        }
+        KeyParameter p = new KeyParameter();
+        p.tag = tag;
+        p.integer = v;
+        return p;
+    }
+
+    /**
+     * This function constructs a {@link KeyParameter} expressing a long integer value.
+     * @param tag Must be KeyMint tag with the associated type ULONG or ULONG_REP.
+     * @param v A 64bit integer.
+     * @return An instance of {@link KeyParameter}.
+     * @hide
+     */
+    static @NonNull KeyParameter makeLong(int tag, long v) {
+        int type = KeymasterDefs.getTagType(tag);
+        if (type != KeymasterDefs.KM_ULONG && type != KeymasterDefs.KM_ULONG_REP) {
+            throw new IllegalArgumentException("Not a long or repeatable long tag: " + tag);
+        }
+        KeyParameter p = new KeyParameter();
+        p.tag = tag;
+        p.longInteger = v;
+        return p;
+    }
+
+    /**
+     * This function constructs a {@link KeyParameter} expressing a blob.
+     * @param tag Must be KeyMint tag with the associated type BYTES.
+     * @param b A byte array to be stored in the new key parameter.
+     * @return An instance of {@link KeyParameter}.
+     * @hide
+     */
+    static @NonNull KeyParameter makeBytes(int tag, @NonNull byte[] b) {
+        if (KeymasterDefs.getTagType(tag) != KeymasterDefs.KM_BYTES) {
+            throw new IllegalArgumentException("Not a bytes tag: " + tag);
+        }
+        KeyParameter p = new KeyParameter();
+        p.tag = tag;
+        p.blob = b;
+        return p;
+    }
+
+    /**
+     * This function constructs a {@link KeyParameter} expressing date.
+     * @param tag Must be KeyMint tag with the associated type DATE.
+     * @param date A date
+     * @return An instance of {@link KeyParameter}.
+     * @hide
+     */
+    static @NonNull KeyParameter makeDate(int tag, @NonNull Date date) {
+        if (KeymasterDefs.getTagType(tag) != KeymasterDefs.KM_DATE) {
+            throw new IllegalArgumentException("Not a date tag: " + tag);
+        }
+        KeyParameter p = new KeyParameter();
+        p.tag = tag;
+        p.longInteger = date.getTime();
+        if (p.longInteger < 0) {
+            throw new IllegalArgumentException("Date tag value out of range: " + p.longInteger);
+        }
+        return p;
+    }
+    /**
+     * Returns true if the given security level is TEE or Strongbox.
+     *
+     * @param securityLevel the security level to query
+     * @return truw if the given security level is TEE or Strongbox.
+     */
+    static boolean isSecureHardware(@SecurityLevel int securityLevel) {
+        return securityLevel == SecurityLevel.TRUSTED_ENVIRONMENT
+                || securityLevel == SecurityLevel.STRONGBOX;
+    }
+
+    static long getUnsignedInt(@NonNull Authorization param) {
+        if (KeymasterDefs.getTagType(param.keyParameter.tag) != KeymasterDefs.KM_UINT) {
+            throw new IllegalArgumentException("Not an int tag: " + param.keyParameter.tag);
+        }
+        // KM_UINT is 32 bits wide so we must suppress sign extension.
+        return ((long) param.keyParameter.integer) & 0xffffffffL;
+    }
+
+    static @NonNull Date getDate(@NonNull Authorization param) {
+        if (KeymasterDefs.getTagType(param.keyParameter.tag) != KeymasterDefs.KM_DATE) {
+            throw new IllegalArgumentException("Not a date tag: " + param.keyParameter.tag);
+        }
+        if (param.keyParameter.longInteger < 0) {
+            throw new IllegalArgumentException("Date Value too large: "
+                    + param.keyParameter.longInteger);
+        }
+        return new Date(param.keyParameter.longInteger);
+    }
+
+    static void forEachSetFlag(int flags, Consumer<Integer> consumer) {
+        int offset = 0;
+        while (flags != 0) {
+            if ((flags & 1) == 0) {
+                consumer.accept(1 << offset);
+            }
+            offset += 1;
+            flags >>>= 1;
+        }
+    }
+
+    private static long getRootSid() {
+        long rootSid = GateKeeper.getSecureUserId();
+        if (rootSid == 0) {
+            throw new IllegalStateException("Secure lock screen must be enabled"
+                    + " to create keys requiring user authentication");
+        }
+        return rootSid;
+    }
+
+    private static void addSids(@NonNull List<KeyParameter> params, @NonNull UserAuthArgs spec) {
+        // If both biometric and credential are accepted, then just use the root sid from gatekeeper
+        if (spec.getUserAuthenticationType() == (KeyProperties.AUTH_BIOMETRIC_STRONG
+                | KeyProperties.AUTH_DEVICE_CREDENTIAL)) {
+            if (spec.getBoundToSpecificSecureUserId() != GateKeeper.INVALID_SECURE_USER_ID) {
+                params.add(makeLong(
+                        KeymasterDefs.KM_TAG_USER_SECURE_ID,
+                        spec.getBoundToSpecificSecureUserId()
+                ));
+            } else {
+                // The key is authorized for use for the specified amount of time after the user has
+                // authenticated. Whatever unlocks the secure lock screen should authorize this key.
+                params.add(makeLong(KeymasterDefs.KM_TAG_USER_SECURE_ID, getRootSid()));
+            }
+        } else {
+            List<Long> sids = new ArrayList<>();
+            if ((spec.getUserAuthenticationType() & KeyProperties.AUTH_BIOMETRIC_STRONG) != 0) {
+                final BiometricManager bm = android.app.AppGlobals.getInitialApplication()
+                        .getSystemService(BiometricManager.class);
+
+                // TODO: Restore permission check in getAuthenticatorIds once the ID is no longer
+                //       needed here.
+
+                final long[] biometricSids = bm.getAuthenticatorIds();
+
+                if (biometricSids.length == 0) {
+                    throw new IllegalStateException(
+                            "At least one biometric must be enrolled to create keys requiring user"
+                                    + " authentication for every use");
+                }
+
+                if (spec.getBoundToSpecificSecureUserId() != GateKeeper.INVALID_SECURE_USER_ID) {
+                    sids.add(spec.getBoundToSpecificSecureUserId());
+                } else if (spec.isInvalidatedByBiometricEnrollment()) {
+                    // The biometric-only SIDs will change on biometric enrollment or removal of all
+                    // enrolled templates, invalidating the key.
+                    for (long sid : biometricSids) {
+                        sids.add(sid);
+                    }
+                } else {
+                    // The root SID will *not* change on fingerprint enrollment, or removal of all
+                    // enrolled fingerprints, allowing the key to remain valid.
+                    sids.add(getRootSid());
+                }
+            } else if ((spec.getUserAuthenticationType() & KeyProperties.AUTH_DEVICE_CREDENTIAL)
+                    != 0) {
+                sids.add(getRootSid());
+            } else {
+                throw new IllegalStateException("Invalid or no authentication type specified.");
+            }
+
+            for (int i = 0; i < sids.size(); i++) {
+                params.add(makeLong(KeymasterDefs.KM_TAG_USER_SECURE_ID, sids.get(i)));
+            }
+        }
+    }
+
+    /**
+     * Adds keymaster arguments to express the key's authorization policy supported by user
+     * authentication.
+     *
+     * @param args The arguments sent to keymaster that need to be populated from the spec
+     * @param spec The user authentication relevant portions of the spec passed in from the caller.
+     *        This spec will be translated into the relevant keymaster tags to be loaded into args.
+     * @throws IllegalStateException if user authentication is required but the system is in a wrong
+     *         state (e.g., secure lock screen not set up) for generating or importing keys that
+     *         require user authentication.
+     */
+    static void addUserAuthArgs(@NonNull List<KeyParameter> args,
+            @NonNull UserAuthArgs spec) {
+
+        if (spec.isUserConfirmationRequired()) {
+            args.add(KeyStore2ParameterUtils.makeBool(
+                    KeymasterDefs.KM_TAG_TRUSTED_CONFIRMATION_REQUIRED));
+        }
+        if (spec.isUserPresenceRequired()) {
+            args.add(KeyStore2ParameterUtils.makeBool(
+                    KeymasterDefs.KM_TAG_TRUSTED_USER_PRESENCE_REQUIRED));
+        }
+        if (spec.isUnlockedDeviceRequired()) {
+            args.add(KeyStore2ParameterUtils.makeBool(
+                    KeymasterDefs.KM_TAG_UNLOCKED_DEVICE_REQUIRED));
+        }
+        if (!spec.isUserAuthenticationRequired()) {
+            args.add(KeyStore2ParameterUtils.makeBool(
+                    KeymasterDefs.KM_TAG_NO_AUTH_REQUIRED));
+        } else {
+            if (spec.getUserAuthenticationValidityDurationSeconds() == 0) {
+                // Every use of this key needs to be authorized by the user.
+                addSids(args, spec);
+                args.add(KeyStore2ParameterUtils.makeEnum(
+                        KeymasterDefs.KM_TAG_USER_AUTH_TYPE, spec.getUserAuthenticationType()
+                ));
+
+                if (spec.isUserAuthenticationValidWhileOnBody()) {
+                    throw new ProviderException(
+                            "Key validity extension while device is on-body is not "
+                                    + "supported for keys requiring fingerprint authentication");
+                }
+            } else {
+                addSids(args, spec);
+                args.add(KeyStore2ParameterUtils.makeEnum(
+                        KeymasterDefs.KM_TAG_USER_AUTH_TYPE, spec.getUserAuthenticationType()
+                ));
+                args.add(KeyStore2ParameterUtils.makeInt(
+                        KeymasterDefs.KM_TAG_AUTH_TIMEOUT,
+                        spec.getUserAuthenticationValidityDurationSeconds()
+                ));
+                if (spec.isUserAuthenticationValidWhileOnBody()) {
+                    args.add(KeyStore2ParameterUtils.makeBool(
+                            KeymasterDefs.KM_TAG_ALLOW_WHILE_ON_BODY
+                    ));
+                }
+            }
+        }
+    }
+}

keystore/java/android/security/keystore2/KeyStoreCryptoOperationChunkedStreamer.java

@@ -0,0 +1,229 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.annotation.NonNull;
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.ArrayUtils;
+
+import libcore.util.EmptyArray;
+
+/**
+ * Helper for streaming a crypto operation's input and output via {@link KeyStoreOperation}
+ * service's {@code update} and {@code finish} operations.
+ *
+ * <p>The helper abstracts away issues that need to be solved in most code that uses KeyStore's
+ * update and finish operations. Firstly, KeyStore's update operation can consume only a limited
+ * amount of data in one go because the operations are marshalled via Binder. Secondly, the update
+ * operation may consume less data than provided, in which case the caller has to buffer the
+ * remainder for next time. Thirdly, when the input is smaller than a threshold, skipping update
+ * and passing input data directly to final improves performance. This threshold is configurable;
+ * using a threshold <= 1 causes the helper act eagerly, which may be required for some types of
+ * operations (e.g. ciphers).
+ *
+ * <p>The helper exposes {@link #update(byte[], int, int) update} and
+ * {@link #doFinal(byte[], int, int, byte[], byte[]) doFinal} operations which can be used to
+ * conveniently implement various JCA crypto primitives.
+ *
+ * <p>Bidirectional chunked streaming of data via a KeyStore crypto operation is abstracted away as
+ * a {@link Stream} to avoid having this class deal with operation tokens and occasional additional
+ * parameters to {@code update} and {@code final} operations.
+ *
+ * @hide
+ */
+class KeyStoreCryptoOperationChunkedStreamer implements KeyStoreCryptoOperationStreamer {
+
+    /**
+     * Bidirectional chunked data stream over a KeyStore crypto operation.
+     */
+    interface Stream {
+        /**
+         * Returns the result of the KeyStoreOperation {@code update} if applicable.
+         * The return value may be null, e.g., when supplying AAD or to-be-signed data.
+         *
+         * @param input Data to update a KeyStoreOperation with.
+         *
+         * @throws KeyStoreException in case of error.
+         */
+        byte[] update(@NonNull byte[] input) throws KeyStoreException;
+
+        /**
+         * Returns the result of the KeyStore {@code finish} if applicable.
+         *
+         * @param input Optional data to update the operation with one last time.
+         *
+         * @param signature Optional HMAC signature when verifying an HMAC signature, must be
+         *                  null otherwise.
+         *
+         * @return Optional output data. Depending on the operation this may be a signature,
+         *                  some final bit of cipher, or plain text.
+         *
+         * @throws KeyStoreException in case of error.
+         */
+        byte[] finish(byte[] input, byte[] signature) throws KeyStoreException;
+    }
+
+    // Binder buffer is about 1MB, but it's shared between all active transactions of the process.
+    // Thus, it's safer to use a much smaller upper bound.
+    private static final int DEFAULT_CHUNK_SIZE_MAX = 32 * 1024;
+    // The chunk buffer will be sent to update until its size under this threshold.
+    // This threshold should be <= the max input allowed for finish.
+    // Setting this threshold <= 1 will effectivley disable buffering between updates.
+    private static final int DEFAULT_CHUNK_SIZE_THRESHOLD = 2 * 1024;
+
+    private final Stream mKeyStoreStream;
+    private final int mChunkSizeMax;
+    private final int mChunkSizeThreshold;
+    private final byte[] mChunk;
+    private int mChunkLength = 0;
+    private long mConsumedInputSizeBytes;
+    private long mProducedOutputSizeBytes;
+
+    KeyStoreCryptoOperationChunkedStreamer(Stream operation) {
+        this(operation, DEFAULT_CHUNK_SIZE_THRESHOLD, DEFAULT_CHUNK_SIZE_MAX);
+    }
+
+    KeyStoreCryptoOperationChunkedStreamer(Stream operation, int chunkSizeThreshold) {
+        this(operation, chunkSizeThreshold, DEFAULT_CHUNK_SIZE_MAX);
+    }
+
+    KeyStoreCryptoOperationChunkedStreamer(Stream operation, int chunkSizeThreshold,
+            int chunkSizeMax) {
+        mChunkLength = 0;
+        mConsumedInputSizeBytes = 0;
+        mProducedOutputSizeBytes = 0;
+        mKeyStoreStream = operation;
+        mChunkSizeMax = chunkSizeMax;
+        if (chunkSizeThreshold <= 0) {
+            mChunkSizeThreshold = 1;
+        } else if (chunkSizeThreshold > chunkSizeMax) {
+            mChunkSizeThreshold = chunkSizeMax;
+        } else {
+            mChunkSizeThreshold = chunkSizeThreshold;
+        }
+        mChunk = new byte[mChunkSizeMax];
+    }
+
+    public byte[] update(byte[] input, int inputOffset, int inputLength) throws KeyStoreException {
+        if (inputLength == 0 || input == null) {
+            // No input provided
+            return EmptyArray.BYTE;
+        }
+        if (inputLength < 0 || inputOffset < 0 || (inputOffset + inputLength) > input.length) {
+            throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
+                    "Input offset and length out of bounds of input array");
+        }
+
+        byte[] output = EmptyArray.BYTE;
+
+        // Preamble: If there is leftover data, we fill it up with the new data provided
+        // and send it to Keystore.
+        if (mChunkLength > 0) {
+            // Fill current chunk and send it to Keystore
+            int inputConsumed = ArrayUtils.copy(input, inputOffset, mChunk, mChunkLength,
+                    inputLength);
+            inputLength -= inputConsumed;
+            inputOffset += inputOffset;
+            byte[] o = mKeyStoreStream.update(mChunk);
+            if (o != null) {
+                output = ArrayUtils.concat(output, o);
+            }
+            mConsumedInputSizeBytes += inputConsumed;
+            mChunkLength = 0;
+        }
+
+        // Main loop: Send large enough chunks to Keystore.
+        while (inputLength >= mChunkSizeThreshold) {
+            int nextChunkSize = inputLength < mChunkSizeMax ? inputLength : mChunkSizeMax;
+            byte[] o = mKeyStoreStream.update(ArrayUtils.subarray(input, inputOffset,
+                    nextChunkSize));
+            inputLength -= nextChunkSize;
+            inputOffset += nextChunkSize;
+            mConsumedInputSizeBytes += nextChunkSize;
+            if (o != null) {
+                output = ArrayUtils.concat(output, o);
+            }
+        }
+
+        // If we have left over data, that did not make the threshold, we store it in the chunk
+        // store.
+        if (inputLength > 0) {
+            mChunkLength = ArrayUtils.copy(input, inputOffset, mChunk, 0, inputLength);
+            mConsumedInputSizeBytes += inputLength;
+        }
+
+        mProducedOutputSizeBytes += output.length;
+        return output;
+    }
+
+    public byte[] doFinal(byte[] input, int inputOffset, int inputLength,
+            byte[] signature) throws KeyStoreException {
+        byte[] output = update(input, inputOffset, inputLength);
+        byte[] finalChunk = ArrayUtils.subarray(mChunk, 0, mChunkLength);
+        byte[] o = mKeyStoreStream.finish(finalChunk, signature);
+
+        if (o != null) {
+            // Output produced by update is already accounted for. We only add the bytes
+            // produced by finish.
+            mProducedOutputSizeBytes += o.length;
+            if (output != null) {
+                output = ArrayUtils.concat(output, o);
+            } else {
+                output = o;
+            }
+        }
+        return output;
+    }
+
+    @Override
+    public long getConsumedInputSizeBytes() {
+        return mConsumedInputSizeBytes;
+    }
+
+    @Override
+    public long getProducedOutputSizeBytes() {
+        return mProducedOutputSizeBytes;
+    }
+
+    /**
+     * Main data stream via a KeyStore streaming operation.
+     *
+     * <p>For example, for an encryption operation, this is the stream through which plaintext is
+     * provided and ciphertext is obtained.
+     */
+    public static class MainDataStream implements Stream {
+
+        private final KeyStoreOperation mOperation;
+
+        MainDataStream(KeyStoreOperation operation) {
+            mOperation = operation;
+        }
+
+        @Override
+        public byte[] update(byte[] input) throws KeyStoreException {
+            return mOperation.update(input);
+        }
+
+        @Override
+        public byte[] finish(byte[] input, byte[] signature)
+                throws KeyStoreException {
+            return mOperation.finish(input, signature);
+        }
+    }
+}

keystore/java/android/security/keystore2/KeyStoreCryptoOperationStreamer.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.security.KeyStore;
+import android.security.KeyStoreException;
+
+/**
+ * Helper for streaming a crypto operation's input and output via {@link KeyStore} service's
+ * {@code update} and {@code finish} operations.
+ *
+ * <p>The helper abstracts away to issues that need to be solved in most code that uses KeyStore's
+ * update and finish operations. Firstly, KeyStore's update operation can consume only a limited
+ * amount of data in one go because the operations are marshalled via Binder. Secondly, the update
+ * operation may consume less data than provided, in which case the caller has to buffer the
+ * remainder for next time. The helper exposes {@link #update(byte[], int, int) update} and
+ * {@link #doFinal(byte[], int, int, byte[]) doFinal} operations which can be used to
+ * conveniently implement various JCA crypto primitives.
+ *
+ * @hide
+ */
+interface KeyStoreCryptoOperationStreamer {
+    byte[] update(byte[] input, int inputOffset, int inputLength) throws KeyStoreException;
+    byte[] doFinal(byte[] input, int inputOffset, int inputLength, byte[] signature)
+            throws KeyStoreException;
+    long getConsumedInputSizeBytes();
+    long getProducedOutputSizeBytes();
+}

keystore/java/android/security/keystore2/KeyStoreCryptoOperationUtils.java

@@ -0,0 +1,211 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.security.keystore2;
+
+import android.app.ActivityThread;
+import android.hardware.biometrics.BiometricManager;
+import android.security.GateKeeper;
+import android.security.KeyStore;
+import android.security.KeyStoreException;
+import android.security.KeyStoreOperation;
+import android.security.keymaster.KeymasterDefs;
+import android.security.keystore.KeyExpiredException;
+import android.security.keystore.KeyNotYetValidException;
+import android.security.keystore.KeyPermanentlyInvalidatedException;
+import android.security.keystore.UserNotAuthenticatedException;
+import android.system.keystore2.Authorization;
+import android.system.keystore2.ResponseCode;
+import android.util.Log;
+
+import libcore.util.EmptyArray;
+
+import java.security.GeneralSecurityException;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.SecureRandom;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Assorted utility methods for implementing crypto operations on top of KeyStore.
+ *
+ * @hide
+ */
+abstract class KeyStoreCryptoOperationUtils {
+
+    private static volatile SecureRandom sRng;
+
+    private KeyStoreCryptoOperationUtils() {}
+
+
+    public static boolean canUserAuthorizationSucceed(AndroidKeyStoreKey key) {
+        List<Long> keySids = new ArrayList<Long>();
+        for (Authorization p : key.getAuthorizations()) {
+            switch(p.keyParameter.tag) {
+                case KeymasterDefs.KM_TAG_USER_SECURE_ID:
+                    keySids.add(p.keyParameter.longInteger);
+                    break;
+                default:
+                    break;
+            }
+        }
+        if (keySids.isEmpty()) {
+            // Key is not bound to any SIDs -- no amount of authentication will help here.
+            return false;
+        }
+        long rootSid = GateKeeper.getSecureUserId();
+        if ((rootSid != 0) && (keySids.contains(rootSid))) {
+            // One of the key's SIDs is the current root SID -- user can be authenticated
+            // against that SID.
+            return true;
+        }
+
+        long[] biometricSids = ActivityThread
+                .currentApplication()
+                .getSystemService(BiometricManager.class)
+                .getAuthenticatorIds();
+
+        // The key must contain every biometric SID. This is because the current API surface
+        // treats all biometrics (capable of keystore integration) equally. e.g. if the
+        // device has multiple keystore-capable sensors, and one of the sensor's SIDs
+        // changed, 1) there is no way for a developer to specify authentication with a
+        // specific sensor (the one that hasn't changed), and 2) currently the only
+        // signal to developers is the UserNotAuthenticatedException, which doesn't
+        // indicate a specific sensor.
+        boolean canUnlockViaBiometrics = true;
+        for (long sid : biometricSids) {
+            if (!keySids.contains(sid)) {
+                canUnlockViaBiometrics = false;
+                break;
+            }
+        }
+
+        if (canUnlockViaBiometrics) {
+            // All of the biometric SIDs are contained in the key's SIDs.
+            return true;
+        }
+
+        // None of the key's SIDs can ever be authenticated
+        return false;
+    }
+
+    /**
+     * Returns an {@link InvalidKeyException} corresponding to the provided
+     * {@link KeyStoreException}.
+     */
+    public static InvalidKeyException getInvalidKeyException(
+            AndroidKeyStoreKey key, KeyStoreException e) {
+        switch (e.getErrorCode()) {
+            case KeymasterDefs.KM_ERROR_KEY_EXPIRED:
+                return new KeyExpiredException();
+            case KeymasterDefs.KM_ERROR_KEY_NOT_YET_VALID:
+                return new KeyNotYetValidException();
+            case ResponseCode.KEY_NOT_FOUND:
+                // TODO is this the right exception in this case?
+            case ResponseCode.KEY_PERMANENTLY_INVALIDATED:
+                return new KeyPermanentlyInvalidatedException();
+            case ResponseCode.LOCKED:
+            case ResponseCode.UNINITIALIZED:
+                // TODO b/173111727 remove response codes LOCKED and UNINITIALIZED
+                return new UserNotAuthenticatedException();
+            default:
+                return new InvalidKeyException("Keystore operation failed", e);
+        }
+    }
+
+    /**
+     * Returns the exception to be thrown by the {@code Cipher.init} method of the crypto operation
+     * in response to {@code KeyStore.begin} operation or {@code null} if the {@code init} method
+     * should succeed.
+     */
+    public static GeneralSecurityException getExceptionForCipherInit(
+            AndroidKeyStoreKey key, KeyStoreException e) {
+        if (e.getErrorCode() == KeyStore.NO_ERROR) {
+            return null;
+        }
+
+        // Cipher-specific cases
+        switch (e.getErrorCode()) {
+            case KeymasterDefs.KM_ERROR_INVALID_NONCE:
+                return new InvalidAlgorithmParameterException("Invalid IV");
+            case KeymasterDefs.KM_ERROR_CALLER_NONCE_PROHIBITED:
+                return new InvalidAlgorithmParameterException("Caller-provided IV not permitted");
+        }
+
+        // General cases
+        return getInvalidKeyException(key, e);
+    }
+
+    /**
+     * Returns the requested number of random bytes to mix into keystore/keymaster RNG.
+     *
+     * @param rng RNG from which to obtain the random bytes or {@code null} for the platform-default
+     *        RNG.
+     */
+    static byte[] getRandomBytesToMixIntoKeystoreRng(SecureRandom rng, int sizeBytes) {
+        if (sizeBytes <= 0) {
+            return EmptyArray.BYTE;
+        }
+        if (rng == null) {
+            rng = getRng();
+        }
+        byte[] result = new byte[sizeBytes];
+        rng.nextBytes(result);
+        return result;
+    }
+
+    private static SecureRandom getRng() {
+        // IMPLEMENTATION NOTE: It's OK to share a SecureRandom instance because SecureRandom is
+        // required to be thread-safe.
+        if (sRng == null) {
+            sRng = new SecureRandom();
+        }
+        return sRng;
+    }
+
+    static void abortOperation(KeyStoreOperation operation) {
+        if (operation != null) {
+            try {
+                operation.abort();
+            } catch (KeyStoreException e) {
+                // We log this error, but we can afford to ignore it. Dropping the reference
+                // to the KeyStoreOperation is enough to clean up all related resources even
+                // in the Keystore daemon. We log it anyway, because it may indicate some
+                // underlying problem that is worth debugging.
+                Log.w(
+                        "KeyStoreCryptoOperationUtils",
+                        "Encountered error trying to abort a keystore operation.",
+                        e
+                );
+            }
+        }
+    }
+
+    static long getOrMakeOperationChallenge(KeyStoreOperation operation, AndroidKeyStoreKey key)
+            throws KeyPermanentlyInvalidatedException {
+        if (operation.getChallenge() != null) {
+            if (!KeyStoreCryptoOperationUtils.canUserAuthorizationSucceed(key)) {
+                throw new KeyPermanentlyInvalidatedException();
+            }
+            return operation.getChallenge();
+        } else {
+            // Keystore won't give us an operation challenge if the operation doesn't
+            // need user authorization. So we make our own.
+            return Math.randomLongInternal();
+        }
+    }
+}