Files
frameworks_base/keystore/java/android/security/KeyStoreParameter.java
Alex Klyubin 1620a65d32 resolved conflicts for merge of 06adabdb to master
Change-Id: Ifb09e2e6242f79cabe76e95eacc982f6cc7e1a6c
2015-04-07 11:39:51 -07:00

474 lines
17 KiB
Java

/*
* Copyright (C) 2013 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.content.Context;
import java.security.Key;
import java.security.KeyPairGenerator;
import java.security.KeyStore.ProtectionParameter;
import java.util.Date;
/**
* This provides the optional parameters that can be specified for
* {@code KeyStore} entries that work with
* <a href="{@docRoot}training/articles/keystore.html">Android KeyStore
* facility</a>. The Android KeyStore facility is accessed through a
* {@link java.security.KeyStore} API using the {@code AndroidKeyStore}
* provider. The {@code context} passed in may be used to pop up some UI to ask
* the user to unlock or initialize the Android KeyStore facility.
* <p>
* Any entries placed in the {@code KeyStore} may be retrieved later. Note that
* there is only one logical instance of the {@code KeyStore} per application
* UID so apps using the {@code sharedUid} facility will also share a
* {@code KeyStore}.
* <p>
* Keys may be generated using the {@link KeyPairGenerator} facility with a
* {@link KeyPairGeneratorSpec} to specify the entry's {@code alias}. A
* self-signed X.509 certificate will be attached to generated entries, but that
* may be replaced at a later time by a certificate signed by a real Certificate
* Authority.
*/
public final class KeyStoreParameter implements ProtectionParameter {
private int mFlags;
private final Date mKeyValidityStart;
private final Date mKeyValidityForOriginationEnd;
private final Date mKeyValidityForConsumptionEnd;
private final @KeyStoreKeyConstraints.PurposeEnum int mPurposes;
private final @KeyStoreKeyConstraints.PaddingEnum int mPaddings;
private final @KeyStoreKeyConstraints.DigestEnum Integer mDigests;
private final @KeyStoreKeyConstraints.BlockModeEnum int mBlockModes;
private final @KeyStoreKeyConstraints.UserAuthenticatorEnum int mUserAuthenticators;
private final int mUserAuthenticationValidityDurationSeconds;
private final boolean mInvalidatedOnNewFingerprintEnrolled;
private KeyStoreParameter(int flags,
Date keyValidityStart,
Date keyValidityForOriginationEnd,
Date keyValidityForConsumptionEnd,
@KeyStoreKeyConstraints.PurposeEnum int purposes,
@KeyStoreKeyConstraints.PaddingEnum int paddings,
@KeyStoreKeyConstraints.DigestEnum Integer digests,
@KeyStoreKeyConstraints.BlockModeEnum int blockModes,
@KeyStoreKeyConstraints.UserAuthenticatorEnum int userAuthenticators,
int userAuthenticationValidityDurationSeconds,
boolean invalidatedOnNewFingerprintEnrolled) {
if ((userAuthenticationValidityDurationSeconds < 0)
&& (userAuthenticationValidityDurationSeconds != -1)) {
throw new IllegalArgumentException(
"userAuthenticationValidityDurationSeconds must not be negative");
}
mFlags = flags;
mKeyValidityStart = keyValidityStart;
mKeyValidityForOriginationEnd = keyValidityForOriginationEnd;
mKeyValidityForConsumptionEnd = keyValidityForConsumptionEnd;
mPurposes = purposes;
mPaddings = paddings;
mDigests = digests;
mBlockModes = blockModes;
mUserAuthenticators = userAuthenticators;
mUserAuthenticationValidityDurationSeconds = userAuthenticationValidityDurationSeconds;
mInvalidatedOnNewFingerprintEnrolled = invalidatedOnNewFingerprintEnrolled;
}
/**
* @hide
*/
public int getFlags() {
return mFlags;
}
/**
* Returns {@code true} if this parameter requires entries to be encrypted
* on the disk.
*/
public boolean isEncryptionRequired() {
return (mFlags & KeyStore.FLAG_ENCRYPTED) != 0;
}
/**
* Gets the time instant before which the key is not yet valid.
*
* @return instant or {@code null} if not restricted.
* @hide
*/
public Date getKeyValidityStart() {
return mKeyValidityStart;
}
/**
* Gets the time instant after which the key is no long valid for decryption and verification.
*
* @return instant or {@code null} if not restricted.
*
* @hide
*/
public Date getKeyValidityForConsumptionEnd() {
return mKeyValidityForConsumptionEnd;
}
/**
* Gets the time instant after which the key is no long valid for encryption and signing.
*
* @return instant or {@code null} if not restricted.
*
* @hide
*/
public Date getKeyValidityForOriginationEnd() {
return mKeyValidityForOriginationEnd;
}
/**
* Gets the set of purposes for which the key can be used.
*
* @hide
*/
public @KeyStoreKeyConstraints.PurposeEnum int getPurposes() {
return mPurposes;
}
/**
* Gets the set of padding schemes to which the key is restricted.
*
* @hide
*/
public @KeyStoreKeyConstraints.PaddingEnum int getPaddings() {
return mPaddings;
}
/**
* Gets the set of digests to which the key is restricted.
*
* @throws IllegalStateException if this restriction has not been specified.
*
* @see #isDigestsSpecified()
*
* @hide
*/
public @KeyStoreKeyConstraints.DigestEnum int getDigests() {
if (mDigests == null) {
throw new IllegalStateException("Digests not specified");
}
return mDigests;
}
/**
* Returns {@code true} if digest restrictions have been specified.
*
* @see #getDigests()
*
* @hide
*/
public boolean isDigestsSpecified() {
return mDigests != null;
}
/**
* Gets the set of block modes to which the key is restricted.
*
* @hide
*/
public @KeyStoreKeyConstraints.BlockModeEnum int getBlockModes() {
return mBlockModes;
}
/**
* Gets the set of user authenticators which protect access to this key. The key can only be
* used iff the user has authenticated to at least one of these user authenticators.
*
* @return user authenticators or {@code 0} if the key can be used without user authentication.
*
* @hide
*/
public @KeyStoreKeyConstraints.UserAuthenticatorEnum int getUserAuthenticators() {
return mUserAuthenticators;
}
/**
* Gets the duration of time (seconds) for which this key can be used after the user
* successfully authenticates to one of the associated user authenticators.
*
* @return duration in seconds or {@code -1} if not restricted. {@code 0} means authentication
* is required for every use of the key.
*
* @hide
*/
public int getUserAuthenticationValidityDurationSeconds() {
return mUserAuthenticationValidityDurationSeconds;
}
/**
* Returns {@code true} if this key must be permanently invalidated once a new fingerprint is
* enrolled. This constraint only has effect if fingerprint reader is one of the user
* authenticators protecting access to this key.
*
* @see #getUserAuthenticators()
*
* @hide
*/
public boolean isInvalidatedOnNewFingerprintEnrolled() {
return mInvalidatedOnNewFingerprintEnrolled;
}
/**
* Builder class for {@link KeyStoreParameter} objects.
* <p>
* This will build protection parameters for use with the
* <a href="{@docRoot}training/articles/keystore.html">Android KeyStore
* facility</a>.
* <p>
* This can be used to require that KeyStore entries be stored encrypted.
* <p>
* Example:
*
* <pre class="prettyprint">
* KeyStoreParameter params = new KeyStoreParameter.Builder(mContext)
* .setEncryptionRequired()
* .build();
* </pre>
*/
public final static class Builder {
private int mFlags;
private Date mKeyValidityStart;
private Date mKeyValidityForOriginationEnd;
private Date mKeyValidityForConsumptionEnd;
private @KeyStoreKeyConstraints.PurposeEnum int mPurposes;
private @KeyStoreKeyConstraints.PaddingEnum int mPaddings;
private @KeyStoreKeyConstraints.DigestEnum Integer mDigests;
private @KeyStoreKeyConstraints.BlockModeEnum int mBlockModes;
private @KeyStoreKeyConstraints.UserAuthenticatorEnum int mUserAuthenticators;
private int mUserAuthenticationValidityDurationSeconds = -1;
private boolean mInvalidatedOnNewFingerprintEnrolled;
/**
* Creates a new instance of the {@code Builder} with the given
* {@code context}. The {@code context} passed in may be used to pop up
* some UI to ask the user to unlock or initialize the Android KeyStore
* facility.
*/
public Builder(Context context) {
if (context == null) {
throw new NullPointerException("context == null");
}
// Context is currently not used, but will be in the future.
}
/**
* Indicates that this key must be encrypted at rest on storage. Note
* that enabling this will require that the user enable a strong lock
* screen (e.g., PIN, password) before creating or using the generated
* key is successful.
*/
public Builder setEncryptionRequired(boolean required) {
if (required) {
mFlags |= KeyStore.FLAG_ENCRYPTED;
} else {
mFlags &= ~KeyStore.FLAG_ENCRYPTED;
}
return this;
}
/**
* Sets the time instant before which the key is not yet valid.
*
* <b>By default, the key is valid at any instant.
*
* @see #setKeyValidityEnd(Date)
*
* @hide
*/
public Builder setKeyValidityStart(Date startDate) {
mKeyValidityStart = startDate;
return this;
}
/**
* Sets the time instant after which the key is no longer valid.
*
* <b>By default, the key is valid at any instant.
*
* @see #setKeyValidityStart(Date)
* @see #setKeyValidityForConsumptionEnd(Date)
* @see #setKeyValidityForOriginationEnd(Date)
*
* @hide
*/
public Builder setKeyValidityEnd(Date endDate) {
setKeyValidityForOriginationEnd(endDate);
setKeyValidityForConsumptionEnd(endDate);
return this;
}
/**
* Sets the time instant after which the key is no longer valid for encryption and signing.
*
* <b>By default, the key is valid at any instant.
*
* @see #setKeyValidityForConsumptionEnd(Date)
*
* @hide
*/
public Builder setKeyValidityForOriginationEnd(Date endDate) {
mKeyValidityForOriginationEnd = endDate;
return this;
}
/**
* Sets the time instant after which the key is no longer valid for decryption and
* verification.
*
* <b>By default, the key is valid at any instant.
*
* @see #setKeyValidityForOriginationEnd(Date)
*
* @hide
*/
public Builder setKeyValidityForConsumptionEnd(Date endDate) {
mKeyValidityForConsumptionEnd = endDate;
return this;
}
/**
* Restricts the key to being used only for the provided set of purposes.
*
* <p>This restriction must be specified. There is no default.
*
* @hide
*/
public Builder setPurposes(@KeyStoreKeyConstraints.PurposeEnum int purposes) {
mPurposes = purposes;
return this;
}
/**
* Restricts the key to being used only with the provided padding schemes. Attempts to use
* the key with any other padding will be rejected.
*
* <p>This restriction must be specified for keys which are used for encryption/decryption.
*
* @hide
*/
public Builder setPaddings(@KeyStoreKeyConstraints.PaddingEnum int paddings) {
mPaddings = paddings;
return this;
}
/**
* Restricts the key to being used only with the provided digests when generating signatures
* or HMACs. Attempts to use the key with any other digest will be rejected.
*
* <p>For HMAC keys, the default is to restrict to the digest specified in
* {@link Key#getAlgorithm()}. For asymmetric signing keys this constraint must be specified
* because there is no default.
*
* @hide
*/
public Builder setDigests(@KeyStoreKeyConstraints.DigestEnum int digests) {
mDigests = digests;
return this;
}
/**
* Restricts the key to being used only with the provided block modes. Attempts to use the
* key with any other block modes will be rejected.
*
* <p>This restriction must be specified for symmetric encryption/decryption keys.
*
* @hide
*/
public Builder setBlockModes(@KeyStoreKeyConstraints.BlockModeEnum int blockModes) {
mBlockModes = blockModes;
return this;
}
/**
* Sets the user authenticators which protect access to this key. The key can only be used
* iff the user has authenticated to at least one of these user authenticators.
*
* <p>By default, the key can be used without user authentication.
*
* @param userAuthenticators user authenticators or {@code 0} if this key can be accessed
* without user authentication.
*
* @see #setUserAuthenticationValidityDurationSeconds(int)
*
* @hide
*/
public Builder setUserAuthenticators(
@KeyStoreKeyConstraints.UserAuthenticatorEnum int userAuthenticators) {
mUserAuthenticators = userAuthenticators;
return this;
}
/**
* Sets the duration of time (seconds) for which this key can be used after the user
* successfully authenticates to one of the associated user authenticators.
*
* <p>By default, the user needs to authenticate for every use of the key.
*
* @param seconds duration in seconds or {@code 0} if the user needs to authenticate for
* every use of the key.
*
* @see #setUserAuthenticators(int)
*
* @hide
*/
public Builder setUserAuthenticationValidityDurationSeconds(int seconds) {
mUserAuthenticationValidityDurationSeconds = seconds;
return this;
}
/**
* Sets whether this key must be invalidated (permanently) whenever a new fingerprint is
* enrolled. This only has effect if fingerprint reader is one of the user authenticators
* protecting access to the key.
*
* <p>By default, enrolling a new fingerprint does not invalidate the key.
*
* @see #setUserAuthenticators(Set)
*
* @hide
*/
public Builder setInvalidatedOnNewFingerprintEnrolled(boolean invalidated) {
mInvalidatedOnNewFingerprintEnrolled = invalidated;
return this;
}
/**
* Builds the instance of the {@code KeyStoreParameter}.
*
* @throws IllegalArgumentException if a required field is missing
* @return built instance of {@code KeyStoreParameter}
*/
public KeyStoreParameter build() {
return new KeyStoreParameter(mFlags,
mKeyValidityStart,
mKeyValidityForOriginationEnd,
mKeyValidityForConsumptionEnd,
mPurposes,
mPaddings,
mDigests,
mBlockModes,
mUserAuthenticators,
mUserAuthenticationValidityDurationSeconds,
mInvalidatedOnNewFingerprintEnrolled);
}
}
}