am 9be1016b: am c48e8cf0: am edd0e6c0: Merge "Refuse to reuse IV in encryption... (7513d53c) · Commits · e / os / android_frameworks_base

keystore/java/android/security/KeyStoreCipherSpi.java

+44 −14

Original line number	Original line	Diff line number	Diff line
	@@ -111,7 +111,9 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	private final @KeyStoreKeyConstraints.BlockModeEnum int mBlockMode;		private final @KeyStoreKeyConstraints.BlockModeEnum int mBlockMode;
	private final @KeyStoreKeyConstraints.PaddingEnum int mPadding;		private final @KeyStoreKeyConstraints.PaddingEnum int mPadding;
	private final int mBlockSizeBytes;		private final int mBlockSizeBytes;
	private final boolean mIvUsed;
			/** Whether this transformation requires an IV. */
			private final boolean mIvRequired;

	// Fields below are populated by Cipher.init and KeyStore.begin and should be preserved after		// Fields below are populated by Cipher.init and KeyStore.begin and should be preserved after
	// doFinal finishes.		// doFinal finishes.
	@@ -119,10 +121,13 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	private KeyStoreSecretKey mKey;		private KeyStoreSecretKey mKey;
	private SecureRandom mRng;		private SecureRandom mRng;
	private boolean mFirstOperationInitiated;		private boolean mFirstOperationInitiated;
	byte[] mIv;		private byte[] mIv;
			/** Whether the current {@code #mIv} has been used by the underlying crypto operation. */
			private boolean mIvHasBeenUsed;

	// Fields below must be reset		// Fields below must be reset after doFinal
	private byte[] mAdditionalEntropyForBegin;		private byte[] mAdditionalEntropyForBegin;

	/**		/**
	* Token referencing this operation inside keystore service. It is initialized by		* Token referencing this operation inside keystore service. It is initialized by
	* {@code engineInit} and is invalidated when {@code engineDoFinal} succeeds and one some		* {@code engineInit} and is invalidated when {@code engineDoFinal} succeeds and one some
	@@ -143,7 +148,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	mBlockMode = blockMode;		mBlockMode = blockMode;
	mPadding = padding;		mPadding = padding;
	mBlockSizeBytes = blockSizeBytes;		mBlockSizeBytes = blockSizeBytes;
	mIvUsed = ivUsed;		mIvRequired = ivUsed;
	}		}

	@Override		@Override
	@@ -170,7 +175,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	}		}

	private void init(int opmode, Key key, SecureRandom random) throws InvalidKeyException {		private void init(int opmode, Key key, SecureRandom random) throws InvalidKeyException {
	reset();		resetAll();
	if (!(key instanceof KeyStoreSecretKey)) {		if (!(key instanceof KeyStoreSecretKey)) {
	throw new InvalidKeyException(		throw new InvalidKeyException(
	"Unsupported key: " + ((key != null) ? key.getClass().getName() : "null"));		"Unsupported key: " + ((key != null) ? key.getClass().getName() : "null"));
	@@ -187,7 +192,25 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	mEncrypting = opmode == Cipher.ENCRYPT_MODE;		mEncrypting = opmode == Cipher.ENCRYPT_MODE;
	}		}

	private void reset() {		private void resetAll() {
			IBinder operationToken = mOperationToken;
			if (operationToken != null) {
			mOperationToken = null;
			mKeyStore.abort(operationToken);
			}
			mEncrypting = false;
			mKey = null;
			mRng = null;
			mFirstOperationInitiated = false;
			mIv = null;
			mIvHasBeenUsed = false;
			mAdditionalEntropyForBegin = null;
			mOperationToken = null;
			mOperationHandle = null;
			mMainDataStreamer = null;
			}

			private void resetWhilePreservingInitState() {
	IBinder operationToken = mOperationToken;		IBinder operationToken = mOperationToken;
	if (operationToken != null) {		if (operationToken != null) {
	mOperationToken = null;		mOperationToken = null;
	@@ -205,6 +228,12 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	if (mKey == null) {		if (mKey == null) {
	throw new IllegalStateException("Not initialized");		throw new IllegalStateException("Not initialized");
	}		}
			if ((mEncrypting) && (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.");
			}

	KeymasterArguments keymasterInputArgs = new KeymasterArguments();		KeymasterArguments keymasterInputArgs = new KeymasterArguments();
	keymasterInputArgs.addInt(KeymasterDefs.KM_TAG_ALGORITHM, mAlgorithm);		keymasterInputArgs.addInt(KeymasterDefs.KM_TAG_ALGORITHM, mAlgorithm);
	@@ -234,6 +263,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	mOperationHandle = opResult.operationHandle;		mOperationHandle = opResult.operationHandle;
	loadAlgorithmSpecificParametersFromBeginResult(keymasterOutputArgs);		loadAlgorithmSpecificParametersFromBeginResult(keymasterOutputArgs);
	mFirstOperationInitiated = true;		mFirstOperationInitiated = true;
			mIvHasBeenUsed = true;
	mMainDataStreamer = new KeyStoreCryptoOperationChunkedStreamer(		mMainDataStreamer = new KeyStoreCryptoOperationChunkedStreamer(
	new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(		new KeyStoreCryptoOperationChunkedStreamer.MainDataStream(
	mKeyStore, opResult.token));		mKeyStore, opResult.token));
	@@ -298,7 +328,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	}		}
	}		}

	reset();		resetWhilePreservingInitState();
	return output;		return output;
	}		}

	@@ -376,7 +406,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	*/		*/
	@Override		@Override
	protected AlgorithmParameters engineGetParameters() {		protected AlgorithmParameters engineGetParameters() {
	if (!mIvUsed) {		if (!mIvRequired) {
	return null;		return null;
	}		}
	if ((mIv != null) && (mIv.length > 0)) {		if ((mIv != null) && (mIv.length > 0)) {
	@@ -408,7 +438,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	*/		*/
	protected void initAlgorithmSpecificParameters(AlgorithmParameterSpec params)		protected void initAlgorithmSpecificParameters(AlgorithmParameterSpec params)
	throws InvalidAlgorithmParameterException {		throws InvalidAlgorithmParameterException {
	if (!mIvUsed) {		if (!mIvRequired) {
	if (params != null) {		if (params != null) {
	throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);		throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);
	}		}
	@@ -447,7 +477,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	*/		*/
	protected void initAlgorithmSpecificParameters(AlgorithmParameters params)		protected void initAlgorithmSpecificParameters(AlgorithmParameters params)
	throws InvalidAlgorithmParameterException {		throws InvalidAlgorithmParameterException {
	if (!mIvUsed) {		if (!mIvRequired) {
	if (params != null) {		if (params != null) {
	throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);		throw new InvalidAlgorithmParameterException("Unsupported parameters: " + params);
	}		}
	@@ -492,7 +522,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	* and thus {@code Cipher.init} needs to be invoked with explicitly provided parameters.		* and thus {@code Cipher.init} needs to be invoked with explicitly provided parameters.
	*/		*/
	protected void initAlgorithmSpecificParameters() throws InvalidKeyException {		protected void initAlgorithmSpecificParameters() throws InvalidKeyException {
	if (!mIvUsed) {		if (!mIvRequired) {
	return;		return;
	}		}

	@@ -515,7 +545,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	if (!mFirstOperationInitiated) {		if (!mFirstOperationInitiated) {
	// First begin operation -- see if we need to provide additional entropy for IV		// First begin operation -- see if we need to provide additional entropy for IV
	// generation.		// generation.
	if (mIvUsed) {		if (mIvRequired) {
	// IV is needed		// IV is needed
	if ((mIv == null) && (mEncrypting)) {		if ((mIv == null) && (mEncrypting)) {
	// TODO: Switch to keymaster-generated IV code below once keymaster supports		// TODO: Switch to keymaster-generated IV code below once keymaster supports
	@@ -534,7 +564,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	}		}
	}		}

	if ((mIvUsed) && (mIv != null)) {		if ((mIvRequired) && (mIv != null)) {
	keymasterArgs.addBlob(KeymasterDefs.KM_TAG_NONCE, mIv);		keymasterArgs.addBlob(KeymasterDefs.KM_TAG_NONCE, mIv);
	}		}
	}		}
	@@ -557,7 +587,7 @@ public abstract class KeyStoreCipherSpi extends CipherSpi implements KeyStoreCry
	returnedIv = null;		returnedIv = null;
	}		}

	if (mIvUsed) {		if (mIvRequired) {
	if (mIv == null) {		if (mIv == null) {
	mIv = returnedIv;		mIv = returnedIv;
	} else if ((returnedIv != null) && (!Arrays.equals(returnedIv, mIv))) {		} else if ((returnedIv != null) && (!Arrays.equals(returnedIv, mIv))) {