android/security/keystore/KeyStoreCryptoOperationChunkedStreamer.java - platform/prebuilts/fullsdk/sources/android-29 - Git at Google

 /*
  * 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.keystore;

 import android.os.IBinder;
 import android.security.KeyStore;
 import android.security.KeyStoreException;
 import android.security.keymaster.KeymasterDefs;
 import android.security.keymaster.OperationResult;

 import libcore.util.EmptyArray;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.security.ProviderException;

 /**
  * 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[], 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 KeyStore {@code update} operation or null if keystore couldn't
          * be reached.
          */
         OperationResult update(byte[] input);

         /**
          * Returns the result of the KeyStore {@code finish} operation or null if keystore couldn't
          * be reached.
          */
         OperationResult finish(byte[] siganture, byte[] additionalEntropy);
     }

     // 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_MAX_CHUNK_SIZE = 64 * 1024;

     private final Stream mKeyStoreStream;
     private final int mMaxChunkSize;

     private byte[] mBuffered = EmptyArray.BYTE;
     private int mBufferedOffset;
     private int mBufferedLength;
     private long mConsumedInputSizeBytes;
     private long mProducedOutputSizeBytes;

     public KeyStoreCryptoOperationChunkedStreamer(Stream operation) {
         this(operation, DEFAULT_MAX_CHUNK_SIZE);
     }

     public KeyStoreCryptoOperationChunkedStreamer(Stream operation, int maxChunkSize) {
         mKeyStoreStream = operation;
         mMaxChunkSize = maxChunkSize;
     }

     @Override
     public byte[] update(byte[] input, int inputOffset, int inputLength) throws KeyStoreException {
         if (inputLength == 0) {
             // No input provided
             return EmptyArray.BYTE;
         }

         ByteArrayOutputStream bufferedOutput = null;

         while (inputLength > 0) {
             byte[] chunk;
             int inputBytesInChunk;
             if ((mBufferedLength + inputLength) > mMaxChunkSize) {
                 // Too much input for one chunk -- extract one max-sized chunk and feed it into the
                 // update operation.
                 inputBytesInChunk = mMaxChunkSize - mBufferedLength;
                 chunk = ArrayUtils.concat(mBuffered, mBufferedOffset, mBufferedLength,
                         input, inputOffset, inputBytesInChunk);
             } else {
                 // All of available input fits into one chunk.
                 if ((mBufferedLength == 0) && (inputOffset == 0)
                         && (inputLength == input.length)) {
                     // Nothing buffered and all of input array needs to be fed into the update
                     // operation.
                     chunk = input;
                     inputBytesInChunk = input.length;
                 } else {
                     // Need to combine buffered data with input data into one array.
                     inputBytesInChunk = inputLength;
                     chunk = ArrayUtils.concat(mBuffered, mBufferedOffset, mBufferedLength,
                             input, inputOffset, inputBytesInChunk);
                 }
             }
             // Update input array references to reflect that some of its bytes are now in mBuffered.
             inputOffset += inputBytesInChunk;
             inputLength -= inputBytesInChunk;
             mConsumedInputSizeBytes += inputBytesInChunk;

             OperationResult opResult = mKeyStoreStream.update(chunk);
             if (opResult == null) {
                 throw new KeyStoreConnectException();
             } else if (opResult.resultCode != KeyStore.NO_ERROR) {
                 throw KeyStore.getKeyStoreException(opResult.resultCode);
             }

             if (opResult.inputConsumed == chunk.length) {
                 // The whole chunk was consumed
                 mBuffered = EmptyArray.BYTE;
                 mBufferedOffset = 0;
                 mBufferedLength = 0;
             } else if (opResult.inputConsumed <= 0) {
                 // Nothing was consumed. More input needed.
                 if (inputLength > 0) {
                     // More input is available, but it wasn't included into the previous chunk
                     // because the chunk reached its maximum permitted size.
                     // Shouldn't have happened.
                     throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
                             "Keystore consumed nothing from max-sized chunk: " + chunk.length
                                     + " bytes");
                 }
                 mBuffered = chunk;
                 mBufferedOffset = 0;
                 mBufferedLength = chunk.length;
             } else if (opResult.inputConsumed < chunk.length) {
                 // The chunk was consumed only partially -- buffer the rest of the chunk
                 mBuffered = chunk;
                 mBufferedOffset = opResult.inputConsumed;
                 mBufferedLength = chunk.length - opResult.inputConsumed;
             } else {
                 throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
                         "Keystore consumed more input than provided. Provided: " + chunk.length
                                 + ", consumed: " + opResult.inputConsumed);
             }

             if ((opResult.output != null) && (opResult.output.length > 0)) {
                 if (inputLength + mBufferedLength > 0) {
                     // More output might be produced in this loop -- buffer the current output
                     if (bufferedOutput == null) {
                         bufferedOutput = new ByteArrayOutputStream();
                     }
                     try {
                         bufferedOutput.write(opResult.output);
                     } catch (IOException e) {
                         throw new ProviderException("Failed to buffer output", e);
                     }
                 } else {
                     // No more output will be produced in this loop
                     byte[] result;
                     if (bufferedOutput == null) {
                         // No previously buffered output
                         result = opResult.output;
                     } else {
                         // There was some previously buffered output
                         try {
                             bufferedOutput.write(opResult.output);
                         } catch (IOException e) {
                             throw new ProviderException("Failed to buffer output", e);
                         }
                         result = bufferedOutput.toByteArray();
                     }
                     mProducedOutputSizeBytes += result.length;
                     return result;
                 }
             }
         }

         byte[] result;
         if (bufferedOutput == null) {
             // No output produced
             result = EmptyArray.BYTE;
         } else {
             result = bufferedOutput.toByteArray();
         }
         mProducedOutputSizeBytes += result.length;
         return result;
     }

     @Override
     public byte[] doFinal(byte[] input, int inputOffset, int inputLength,
             byte[] signature, byte[] additionalEntropy) throws KeyStoreException {
         if (inputLength == 0) {
             // No input provided -- simplify the rest of the code
             input = EmptyArray.BYTE;
             inputOffset = 0;
         }

         // Flush all buffered input and provided input into keystore/keymaster.
         byte[] output = update(input, inputOffset, inputLength);
         output = ArrayUtils.concat(output, flush());

         OperationResult opResult = mKeyStoreStream.finish(signature, additionalEntropy);
         if (opResult == null) {
             throw new KeyStoreConnectException();
         } else if (opResult.resultCode != KeyStore.NO_ERROR) {
             throw KeyStore.getKeyStoreException(opResult.resultCode);
         }
         mProducedOutputSizeBytes += opResult.output.length;

         return ArrayUtils.concat(output, opResult.output);
     }

     public byte[] flush() throws KeyStoreException {
         if (mBufferedLength <= 0) {
             return EmptyArray.BYTE;
         }

         // Keep invoking the update operation with remaining buffered data until either all of the
         // buffered data is consumed or until update fails to consume anything.
         ByteArrayOutputStream bufferedOutput = null;
         while (mBufferedLength > 0) {
             byte[] chunk = ArrayUtils.subarray(mBuffered, mBufferedOffset, mBufferedLength);
             OperationResult opResult = mKeyStoreStream.update(chunk);
             if (opResult == null) {
                 throw new KeyStoreConnectException();
             } else if (opResult.resultCode != KeyStore.NO_ERROR) {
                 throw KeyStore.getKeyStoreException(opResult.resultCode);
             }

             if (opResult.inputConsumed <= 0) {
                 // Nothing was consumed. Break out of the loop to avoid an infinite loop.
                 break;
             }

             if (opResult.inputConsumed >= chunk.length) {
                 // All of the input was consumed
                 mBuffered = EmptyArray.BYTE;
                 mBufferedOffset = 0;
                 mBufferedLength = 0;
             } else {
                 // Some of the input was not consumed
                 mBuffered = chunk;
                 mBufferedOffset = opResult.inputConsumed;
                 mBufferedLength = chunk.length - opResult.inputConsumed;
             }

             if (opResult.inputConsumed > chunk.length) {
                 throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
                         "Keystore consumed more input than provided. Provided: "
                                 + chunk.length + ", consumed: " + opResult.inputConsumed);
             }

             if ((opResult.output != null) && (opResult.output.length > 0)) {
                 // Some output was produced by this update operation
                 if (bufferedOutput == null) {
                     // No output buffered yet.
                     if (mBufferedLength == 0) {
                         // No more output will be produced by this flush operation
                         mProducedOutputSizeBytes += opResult.output.length;
                         return opResult.output;
                     } else {
                         // More output might be produced by this flush operation -- buffer output.
                         bufferedOutput = new ByteArrayOutputStream();
                     }
                 }
                 // Buffer the output from this update operation
                 try {
                     bufferedOutput.write(opResult.output);
                 } catch (IOException e) {
                     throw new ProviderException("Failed to buffer output", e);
                 }
             }
         }

         if (mBufferedLength > 0) {
             throw new KeyStoreException(KeymasterDefs.KM_ERROR_INVALID_INPUT_LENGTH,
                     "Keystore failed to consume last "
                             + ((mBufferedLength != 1) ? (mBufferedLength + " bytes") : "byte")
                             + " of input");
         }

         byte[] result = (bufferedOutput != null) ? bufferedOutput.toByteArray() : EmptyArray.BYTE;
         mProducedOutputSizeBytes += result.length;
         return result;
     }

     @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 KeyStore mKeyStore;
         private final IBinder mOperationToken;

         public MainDataStream(KeyStore keyStore, IBinder operationToken) {
             mKeyStore = keyStore;
             mOperationToken = operationToken;
         }

         @Override
         public OperationResult update(byte[] input) {
             return mKeyStore.update(mOperationToken, null, input);
         }

         @Override
         public OperationResult finish(byte[] signature, byte[] additionalEntropy) {
             return mKeyStore.finish(mOperationToken, null, signature, additionalEntropy);
         }
     }
 }
	/*
	* 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.keystore;

	import android.os.IBinder;
	import android.security.KeyStore;
	import android.security.KeyStoreException;
	import android.security.keymaster.KeymasterDefs;
	import android.security.keymaster.OperationResult;

	import libcore.util.EmptyArray;

	import java.io.ByteArrayOutputStream;
	import java.io.IOException;
	import java.security.ProviderException;

	/**
	* 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[], 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 KeyStore {@code update} operation or null if keystore couldn't
	* be reached.
	*/
	OperationResult update(byte[] input);

	/**
	* Returns the result of the KeyStore {@code finish} operation or null if keystore couldn't
	* be reached.
	*/
	OperationResult finish(byte[] siganture, byte[] additionalEntropy);
	}

	// 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_MAX_CHUNK_SIZE = 64 * 1024;

	private final Stream mKeyStoreStream;
	private final int mMaxChunkSize;

	private byte[] mBuffered = EmptyArray.BYTE;
	private int mBufferedOffset;
	private int mBufferedLength;
	private long mConsumedInputSizeBytes;
	private long mProducedOutputSizeBytes;

	public KeyStoreCryptoOperationChunkedStreamer(Stream operation) {
	this(operation, DEFAULT_MAX_CHUNK_SIZE);
	}

	public KeyStoreCryptoOperationChunkedStreamer(Stream operation, int maxChunkSize) {
	mKeyStoreStream = operation;
	mMaxChunkSize = maxChunkSize;
	}

	@Override
	public byte[] update(byte[] input, int inputOffset, int inputLength) throws KeyStoreException {
	if (inputLength == 0) {
	// No input provided
	return EmptyArray.BYTE;
	}

	ByteArrayOutputStream bufferedOutput = null;

	while (inputLength > 0) {
	byte[] chunk;
	int inputBytesInChunk;
	if ((mBufferedLength + inputLength) > mMaxChunkSize) {
	// Too much input for one chunk -- extract one max-sized chunk and feed it into the
	// update operation.
	inputBytesInChunk = mMaxChunkSize - mBufferedLength;
	chunk = ArrayUtils.concat(mBuffered, mBufferedOffset, mBufferedLength,
	input, inputOffset, inputBytesInChunk);
	} else {
	// All of available input fits into one chunk.
	if ((mBufferedLength == 0) && (inputOffset == 0)
	&& (inputLength == input.length)) {
	// Nothing buffered and all of input array needs to be fed into the update
	// operation.
	chunk = input;
	inputBytesInChunk = input.length;
	} else {
	// Need to combine buffered data with input data into one array.
	inputBytesInChunk = inputLength;
	chunk = ArrayUtils.concat(mBuffered, mBufferedOffset, mBufferedLength,
	input, inputOffset, inputBytesInChunk);
	}
	}
	// Update input array references to reflect that some of its bytes are now in mBuffered.
	inputOffset += inputBytesInChunk;
	inputLength -= inputBytesInChunk;
	mConsumedInputSizeBytes += inputBytesInChunk;

	OperationResult opResult = mKeyStoreStream.update(chunk);
	if (opResult == null) {
	throw new KeyStoreConnectException();
	} else if (opResult.resultCode != KeyStore.NO_ERROR) {
	throw KeyStore.getKeyStoreException(opResult.resultCode);
	}

	if (opResult.inputConsumed == chunk.length) {
	// The whole chunk was consumed
	mBuffered = EmptyArray.BYTE;
	mBufferedOffset = 0;
	mBufferedLength = 0;
	} else if (opResult.inputConsumed <= 0) {
	// Nothing was consumed. More input needed.
	if (inputLength > 0) {
	// More input is available, but it wasn't included into the previous chunk
	// because the chunk reached its maximum permitted size.
	// Shouldn't have happened.
	throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
	"Keystore consumed nothing from max-sized chunk: " + chunk.length
	+ " bytes");
	}
	mBuffered = chunk;
	mBufferedOffset = 0;
	mBufferedLength = chunk.length;
	} else if (opResult.inputConsumed < chunk.length) {
	// The chunk was consumed only partially -- buffer the rest of the chunk
	mBuffered = chunk;
	mBufferedOffset = opResult.inputConsumed;
	mBufferedLength = chunk.length - opResult.inputConsumed;
	} else {
	throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
	"Keystore consumed more input than provided. Provided: " + chunk.length
	+ ", consumed: " + opResult.inputConsumed);
	}

	if ((opResult.output != null) && (opResult.output.length > 0)) {
	if (inputLength + mBufferedLength > 0) {
	// More output might be produced in this loop -- buffer the current output
	if (bufferedOutput == null) {
	bufferedOutput = new ByteArrayOutputStream();
	}
	try {
	bufferedOutput.write(opResult.output);
	} catch (IOException e) {
	throw new ProviderException("Failed to buffer output", e);
	}
	} else {
	// No more output will be produced in this loop
	byte[] result;
	if (bufferedOutput == null) {
	// No previously buffered output
	result = opResult.output;
	} else {
	// There was some previously buffered output
	try {
	bufferedOutput.write(opResult.output);
	} catch (IOException e) {
	throw new ProviderException("Failed to buffer output", e);
	}
	result = bufferedOutput.toByteArray();
	}
	mProducedOutputSizeBytes += result.length;
	return result;
	}
	}
	}

	byte[] result;
	if (bufferedOutput == null) {
	// No output produced
	result = EmptyArray.BYTE;
	} else {
	result = bufferedOutput.toByteArray();
	}
	mProducedOutputSizeBytes += result.length;
	return result;
	}

	@Override
	public byte[] doFinal(byte[] input, int inputOffset, int inputLength,
	byte[] signature, byte[] additionalEntropy) throws KeyStoreException {
	if (inputLength == 0) {
	// No input provided -- simplify the rest of the code
	input = EmptyArray.BYTE;
	inputOffset = 0;
	}

	// Flush all buffered input and provided input into keystore/keymaster.
	byte[] output = update(input, inputOffset, inputLength);
	output = ArrayUtils.concat(output, flush());

	OperationResult opResult = mKeyStoreStream.finish(signature, additionalEntropy);
	if (opResult == null) {
	throw new KeyStoreConnectException();
	} else if (opResult.resultCode != KeyStore.NO_ERROR) {
	throw KeyStore.getKeyStoreException(opResult.resultCode);
	}
	mProducedOutputSizeBytes += opResult.output.length;

	return ArrayUtils.concat(output, opResult.output);
	}

	public byte[] flush() throws KeyStoreException {
	if (mBufferedLength <= 0) {
	return EmptyArray.BYTE;
	}

	// Keep invoking the update operation with remaining buffered data until either all of the
	// buffered data is consumed or until update fails to consume anything.
	ByteArrayOutputStream bufferedOutput = null;
	while (mBufferedLength > 0) {
	byte[] chunk = ArrayUtils.subarray(mBuffered, mBufferedOffset, mBufferedLength);
	OperationResult opResult = mKeyStoreStream.update(chunk);
	if (opResult == null) {
	throw new KeyStoreConnectException();
	} else if (opResult.resultCode != KeyStore.NO_ERROR) {
	throw KeyStore.getKeyStoreException(opResult.resultCode);
	}

	if (opResult.inputConsumed <= 0) {
	// Nothing was consumed. Break out of the loop to avoid an infinite loop.
	break;
	}

	if (opResult.inputConsumed >= chunk.length) {
	// All of the input was consumed
	mBuffered = EmptyArray.BYTE;
	mBufferedOffset = 0;
	mBufferedLength = 0;
	} else {
	// Some of the input was not consumed
	mBuffered = chunk;
	mBufferedOffset = opResult.inputConsumed;
	mBufferedLength = chunk.length - opResult.inputConsumed;
	}

	if (opResult.inputConsumed > chunk.length) {
	throw new KeyStoreException(KeymasterDefs.KM_ERROR_UNKNOWN_ERROR,
	"Keystore consumed more input than provided. Provided: "
	+ chunk.length + ", consumed: " + opResult.inputConsumed);
	}

	if ((opResult.output != null) && (opResult.output.length > 0)) {
	// Some output was produced by this update operation
	if (bufferedOutput == null) {
	// No output buffered yet.
	if (mBufferedLength == 0) {
	// No more output will be produced by this flush operation
	mProducedOutputSizeBytes += opResult.output.length;
	return opResult.output;
	} else {
	// More output might be produced by this flush operation -- buffer output.
	bufferedOutput = new ByteArrayOutputStream();
	}
	}
	// Buffer the output from this update operation
	try {
	bufferedOutput.write(opResult.output);
	} catch (IOException e) {
	throw new ProviderException("Failed to buffer output", e);
	}
	}
	}

	if (mBufferedLength > 0) {
	throw new KeyStoreException(KeymasterDefs.KM_ERROR_INVALID_INPUT_LENGTH,
	"Keystore failed to consume last "
	+ ((mBufferedLength != 1) ? (mBufferedLength + " bytes") : "byte")
	+ " of input");
	}

	byte[] result = (bufferedOutput != null) ? bufferedOutput.toByteArray() : EmptyArray.BYTE;
	mProducedOutputSizeBytes += result.length;
	return result;
	}

	@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 KeyStore mKeyStore;
	private final IBinder mOperationToken;

	public MainDataStream(KeyStore keyStore, IBinder operationToken) {
	mKeyStore = keyStore;
	mOperationToken = operationToken;
	}

	@Override
	public OperationResult update(byte[] input) {
	return mKeyStore.update(mOperationToken, null, input);
	}

	@Override
	public OperationResult finish(byte[] signature, byte[] additionalEntropy) {
	return mKeyStore.finish(mOperationToken, null, signature, additionalEntropy);
	}
	}
	}