Keystore uses 0 for invalid operation handles.

This propagates the concept that 0 is an invalid crypto operation
handle to the outside of AndroidKeyStore abstraction.

Bug: 20864436
Change-Id: I1e5abb66c5d41d8fc32aac44372495a708c2b6e2

4 files changed, 19 insertions, 13 deletions

diff --git a/keystore/java/android/security/AndroidKeyStoreProvider.java b/keystore/java/android/security/AndroidKeyStoreProvider.java
index 518067b..257ab54 100644
--- a/keystore/java/android/security/AndroidKeyStoreProvider.java
+++ b/keystore/java/android/security/AndroidKeyStoreProvider.java
@@ -104,13 +104,13 @@ public class AndroidKeyStoreProvider extends Provider {
      *
      * <p>The following primitives are supported: {@link Cipher} and {@link Mac}.
      *
-     * @return KeyStore operation handle or {@code null} if the provided primitive's KeyStore
-     *         operation is not in progress.
+     * @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.
      */
-    public static Long getKeyStoreOperationHandle(Object cryptoPrimitive) {
+    public static long getKeyStoreOperationHandle(Object cryptoPrimitive) {
         if (cryptoPrimitive == null) {
             throw new NullPointerException();
         }
diff --git a/keystore/java/android/security/KeyStoreCipherSpi.java b/keystore/java/android/security/KeyStoreCipherSpi.java
index 20dd524..094aa75 100644
--- a/keystore/java/android/security/KeyStoreCipherSpi.java
+++ b/keystore/java/android/security/KeyStoreCipherSpi.java
@@ -134,7 +134,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
      * error conditions in between.
      */
     private IBinder mOperationToken;
-    private Long mOperationHandle;
+    private long mOperationHandle;
     private KeyStoreCryptoOperationChunkedStreamer mMainDataStreamer;
 
     /**
@@ -247,7 +247,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
         mIvHasBeenUsed = false;
         mAdditionalEntropyForBegin = null;
         mOperationToken = null;
-        mOperationHandle = null;
+        mOperationHandle = 0;
         mMainDataStreamer = null;
         mCachedException = null;
     }
@@ -258,7 +258,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
             mOperationToken = null;
             mKeyStore.abort(operationToken);
         }
-        mOperationHandle = null;
+        mOperationHandle = 0;
         mMainDataStreamer = null;
         mAdditionalEntropyForBegin = null;
         mCachedException = null;
@@ -322,6 +322,9 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
         if (mOperationToken == null) {
             throw new IllegalStateException("Keystore returned null operation token");
         }
+        if (mOperationHandle == 0) {
+            throw new IllegalStateException("Keystore returned invalid operation handle");
+        }
 
         loadAlgorithmSpecificParametersFromBeginResult(keymasterOutputArgs);
         mFirstOperationInitiated = true;
@@ -471,7 +474,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
     }
 
     @Override
-    public Long getOperationHandle() {
+    public long getOperationHandle() {
         return mOperationHandle;
     }
 
diff --git a/keystore/java/android/security/KeyStoreCryptoOperation.java b/keystore/java/android/security/KeyStoreCryptoOperation.java
index 19abd05..c5cf211 100644
--- a/keystore/java/android/security/KeyStoreCryptoOperation.java
+++ b/keystore/java/android/security/KeyStoreCryptoOperation.java
@@ -25,7 +25,7 @@ public interface KeyStoreCryptoOperation {
     /**
      * Gets the KeyStore operation handle of this crypto operation.
      *
-     * @return handle or {@code null} if the KeyStore operation is not in progress.
+     * @return handle or {@code 0} if the KeyStore operation is not in progress.
      */
-    Long getOperationHandle();
+    long getOperationHandle();
 }
diff --git a/keystore/java/android/security/KeyStoreHmacSpi.java b/keystore/java/android/security/KeyStoreHmacSpi.java
index e993b50..0dbe788 100644
--- a/keystore/java/android/security/KeyStoreHmacSpi.java
+++ b/keystore/java/android/security/KeyStoreHmacSpi.java
@@ -75,7 +75,7 @@ public abstract class KeyStoreHmacSpi extends MacSpi implements KeyStoreCryptoOp
     // Fields below are reset when engineDoFinal succeeds.
     private KeyStoreCryptoOperationChunkedStreamer mChunkedStreamer;
     private IBinder mOperationToken;
-    private Long mOperationHandle;
+    private long mOperationHandle;
 
     protected KeyStoreHmacSpi(int keymasterDigest) {
         mKeymasterDigest = keymasterDigest;
@@ -128,7 +128,7 @@ public abstract class KeyStoreHmacSpi extends MacSpi implements KeyStoreCryptoOp
             mOperationToken = null;
             mKeyStore.abort(operationToken);
         }
-        mOperationHandle = null;
+        mOperationHandle = 0;
         mChunkedStreamer = null;
     }
 
@@ -138,7 +138,7 @@ public abstract class KeyStoreHmacSpi extends MacSpi implements KeyStoreCryptoOp
             mOperationToken = null;
             mKeyStore.abort(operationToken);
         }
-        mOperationHandle = null;
+        mOperationHandle = 0;
         mChunkedStreamer = null;
     }
 
@@ -187,6 +187,9 @@ public abstract class KeyStoreHmacSpi extends MacSpi implements KeyStoreCryptoOp
         if (mOperationToken == null) {
             throw new IllegalStateException("Keystore returned null operation token");
         }
+        if (mOperationHandle == 0) {
+            throw new IllegalStateException("Keystore returned invalid operation handle");
+        }
 
         mChunkedStreamer = new KeyStoreCryptoOperationChunkedStreamer(
                 new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(
@@ -249,7 +252,7 @@ public abstract class KeyStoreHmacSpi extends MacSpi implements KeyStoreCryptoOp
     }
 
     @Override
-    public Long getOperationHandle() {
+    public long getOperationHandle() {
         return mOperationHandle;
     }
 }