Merge "Increase instant app privacy with dummy data"

core/java/android/content/pm/InstantAppRequest.java

@@ -18,12 +18,14 @@ package android.content.pm;
 
 import android.content.Intent;
 import android.os.Bundle;
+import android.text.TextUtils;
 
 /**
  * Information needed to make an instant application resolution request.
  * @hide
  */
 public final class InstantAppRequest {
+
     /** Response from the first phase of instant application resolution */
     public final AuxiliaryResolveInfo responseObj;
     /** The original intent that triggered instant application resolution */
@@ -40,6 +42,8 @@ public final class InstantAppRequest {
     public final Bundle verificationBundle;
     /** Whether resolution occurs because an application is starting */
     public final boolean resolveForStart;
+    /** The instant app digest for this request */
+    public final InstantAppResolveInfo.InstantAppDigest digest;
 
     public InstantAppRequest(AuxiliaryResolveInfo responseObj, Intent origIntent,
             String resolvedType, String callingPackage, int userId, Bundle verificationBundle,
@@ -51,5 +55,11 @@ public final class InstantAppRequest {
         this.userId = userId;
         this.verificationBundle = verificationBundle;
         this.resolveForStart = resolveForStart;
+        if (origIntent.getData() != null && !TextUtils.isEmpty(origIntent.getData().getHost())) {
+            digest = new InstantAppResolveInfo.InstantAppDigest(
+                    origIntent.getData().getHost(), 5 /*maxDigests*/);
+        } else {
+            digest = InstantAppResolveInfo.InstantAppDigest.UNDEFINED;
+        }
     }
 }

core/java/android/content/pm/InstantAppResolveInfo.java

@@ -26,10 +26,13 @@ import android.os.Parcelable;
 
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
+import java.util.Random;
 
 /**
  * Describes an externally resolvable instant application. There are three states that this class
@@ -227,14 +230,25 @@ public final class InstantAppResolveInfo implements Parcelable {
      */
     @SystemApi
     public static final class InstantAppDigest implements Parcelable {
-        private static final int DIGEST_MASK = 0xfffff000;
-
+        static final int DIGEST_MASK = 0xfffff000;
         public static final InstantAppDigest UNDEFINED =
                 new InstantAppDigest(new byte[][]{}, new int[]{});
+
+        private static Random sRandom = null;
+        static {
+            try {
+                sRandom = SecureRandom.getInstance("SHA1PRNG");
+            } catch (NoSuchAlgorithmException e) {
+                // oh well
+                sRandom = new Random();
+            }
+        }
         /** Full digest of the domain hashes */
         private final byte[][] mDigestBytes;
-        /** The first 4 bytes of the domain hashes */
+        /** The first 5 bytes of the domain hashes */
         private final int[] mDigestPrefix;
+        /** The first 5 bytes of the domain hashes interspersed with random data */
+        private int[] mDigestPrefixSecure;
 
         public InstantAppDigest(@NonNull String hostName) {
             this(hostName, -1 /*maxDigests*/);
@@ -306,6 +320,7 @@ public final class InstantAppResolveInfo implements Parcelable {
                 }
             }
             mDigestPrefix = in.createIntArray();
+            mDigestPrefixSecure = in.createIntArray();
         }
 
         public byte[][] getDigestBytes() {
@@ -316,6 +331,26 @@ public final class InstantAppResolveInfo implements Parcelable {
             return mDigestPrefix;
         }
 
+        /**
+         * Returns a digest prefix with additional random prefixes interspersed.
+         * @hide
+         */
+        public int[] getDigestPrefixSecure() {
+            if (this == InstantAppResolveInfo.InstantAppDigest.UNDEFINED) {
+                return getDigestPrefix();
+            } else if (mDigestPrefixSecure == null) {
+                // let's generate some random data to intersperse throughout the set of prefixes
+                final int realSize = getDigestPrefix().length;
+                final int manufacturedSize = realSize + 10 + sRandom.nextInt(10);
+                mDigestPrefixSecure = Arrays.copyOf(getDigestPrefix(), manufacturedSize);
+                for (int i = realSize; i < manufacturedSize; i++) {
+                    mDigestPrefixSecure[i] = sRandom.nextInt() & DIGEST_MASK;
+                }
+                Arrays.sort(mDigestPrefixSecure);
+            }
+            return mDigestPrefixSecure;
+        }
+
         @Override
         public int describeContents() {
             return 0;
@@ -323,6 +358,11 @@ public final class InstantAppResolveInfo implements Parcelable {
 
         @Override
         public void writeToParcel(Parcel out, int flags) {
+            final boolean isUndefined = this == UNDEFINED;
+            out.writeBoolean(isUndefined);
+            if (isUndefined) {
+                return;
+            }
             if (mDigestBytes == null) {
                 out.writeInt(-1);
             } else {
@@ -332,6 +372,7 @@ public final class InstantAppResolveInfo implements Parcelable {
                 }
             }
             out.writeIntArray(mDigestPrefix);
+            out.writeIntArray(mDigestPrefixSecure);
         }
 
         @SuppressWarnings("hiding")
@@ -339,6 +380,9 @@ public final class InstantAppResolveInfo implements Parcelable {
                 new Parcelable.Creator<InstantAppDigest>() {
             @Override
             public InstantAppDigest createFromParcel(Parcel in) {
+                if (in.readBoolean() /* is undefined */) {
+                    return UNDEFINED;
+                }
                 return new InstantAppDigest(in);
             }
             @Override

services/core/java/com/android/server/pm/InstantAppResolver.java

@@ -126,17 +126,16 @@ public abstract class InstantAppResolver {
         final Intent origIntent = requestObj.origIntent;
         final Intent sanitizedIntent = sanitizeIntent(origIntent);
 
-        final InstantAppDigest digest = getInstantAppDigest(origIntent);
-        final int[] shaPrefix = digest.getDigestPrefix();
         AuxiliaryResolveInfo resolveInfo = null;
         @ResolutionStatus int resolutionStatus = RESOLUTION_SUCCESS;
         try {
             final List<InstantAppResolveInfo> instantAppResolveInfoList =
-                    connection.getInstantAppResolveInfoList(sanitizedIntent, shaPrefix, token);
+                    connection.getInstantAppResolveInfoList(sanitizedIntent,
+                            requestObj.digest.getDigestPrefixSecure(), token);
             if (instantAppResolveInfoList != null && instantAppResolveInfoList.size() > 0) {
                 resolveInfo = InstantAppResolver.filterInstantAppIntent(
                         instantAppResolveInfoList, origIntent, requestObj.resolvedType,
-                        requestObj.userId, origIntent.getPackage(), digest, token);
+                        requestObj.userId, origIntent.getPackage(), requestObj.digest, token);
             }
         } catch (ConnectionException e) {
             if (e.failure == ConnectionException.FAILURE_BIND) {
@@ -166,12 +165,6 @@ public abstract class InstantAppResolver {
         return resolveInfo;
     }
 
-    private static InstantAppDigest getInstantAppDigest(Intent origIntent) {
-        return origIntent.getData() != null && !TextUtils.isEmpty(origIntent.getData().getHost())
-                ? new InstantAppDigest(origIntent.getData().getHost(), 5 /*maxDigests*/)
-                : InstantAppDigest.UNDEFINED;
-    }
-
     public static void doInstantAppResolutionPhaseTwo(Context context,
             InstantAppResolverConnection connection, InstantAppRequest requestObj,
             ActivityInfo instantAppInstaller, Handler callbackHandler) {
@@ -182,8 +175,6 @@ public abstract class InstantAppResolver {
         }
         final Intent origIntent = requestObj.origIntent;
         final Intent sanitizedIntent = sanitizeIntent(origIntent);
-        final InstantAppDigest digest = getInstantAppDigest(origIntent);
-        final int[] shaPrefix = digest.getDigestPrefix();
 
         final PhaseTwoCallback callback = new PhaseTwoCallback() {
             @Override
@@ -194,7 +185,8 @@ public abstract class InstantAppResolver {
                     final AuxiliaryResolveInfo instantAppIntentInfo =
                             InstantAppResolver.filterInstantAppIntent(
                                     instantAppResolveInfoList, origIntent, null /*resolvedType*/,
-                                    0 /*userId*/, origIntent.getPackage(), digest, token);
+                                    0 /*userId*/, origIntent.getPackage(), requestObj.digest,
+                                    token);
                     if (instantAppIntentInfo != null) {
                         failureIntent = instantAppIntentInfo.failureIntent;
                     } else {
@@ -225,8 +217,9 @@ public abstract class InstantAppResolver {
             }
         };
         try {
-            connection.getInstantAppIntentFilterList(sanitizedIntent, shaPrefix, token, callback,
-                    callbackHandler, startTime);
+            connection.getInstantAppIntentFilterList(sanitizedIntent,
+                    requestObj.digest.getDigestPrefixSecure(), token, callback, callbackHandler,
+                    startTime);
         } catch (ConnectionException e) {
             @ResolutionStatus int resolutionStatus = RESOLUTION_FAILURE;
             if (e.failure == ConnectionException.FAILURE_BIND) {