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8253821: Improve ByteBuffer performance with GCM
Reviewed-by: xuelei, valeriep
This commit is contained in:
parent
3da30e991a
commit
cc1915b3b3
15 changed files with 2135 additions and 158 deletions
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@ -25,13 +25,21 @@
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package com.sun.crypto.provider;
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import java.util.Arrays;
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import java.io.*;
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import java.security.*;
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import javax.crypto.*;
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import static com.sun.crypto.provider.AESConstants.AES_BLOCK_SIZE;
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import sun.nio.ch.DirectBuffer;
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import sun.security.util.ArrayUtil;
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import javax.crypto.AEADBadTagException;
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import javax.crypto.IllegalBlockSizeException;
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import javax.crypto.ShortBufferException;
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import java.io.ByteArrayOutputStream;
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import java.io.IOException;
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import java.nio.ByteBuffer;
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import java.security.InvalidAlgorithmParameterException;
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import java.security.InvalidKeyException;
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import java.security.ProviderException;
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import static com.sun.crypto.provider.AESConstants.AES_BLOCK_SIZE;
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/**
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* This class represents ciphers in GaloisCounter (GCM) mode.
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@ -68,9 +76,12 @@ final class GaloisCounterMode extends FeedbackCipher {
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private ByteArrayOutputStream aadBuffer = new ByteArrayOutputStream();
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private int sizeOfAAD = 0;
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// buffer for storing input in decryption, not used for encryption
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// buffer data for crypto operation
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private ByteArrayOutputStream ibuffer = null;
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// Original dst buffer if there was an overlap situation
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private ByteBuffer originalDst = null;
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// in bytes; need to convert to bits (default value 128) when needed
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private int tagLenBytes = DEFAULT_TAG_LEN;
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@ -177,8 +188,17 @@ final class GaloisCounterMode extends FeedbackCipher {
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return j0;
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}
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private static void checkDataLength(int processed, int len) {
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if (processed > MAX_BUF_SIZE - len) {
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/**
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* Calculate if the given data lengths and the already processed data
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* exceeds the maximum allowed processed data by GCM.
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* @param lengths lengths of unprocessed data.
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*/
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private void checkDataLength(int ... lengths) {
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int max = MAX_BUF_SIZE;
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for (int len : lengths) {
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max = Math.subtractExact(max, len);
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}
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if (processed > max) {
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throw new ProviderException("SunJCE provider only supports " +
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"input size up to " + MAX_BUF_SIZE + " bytes");
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}
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@ -426,6 +446,64 @@ final class GaloisCounterMode extends FeedbackCipher {
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}
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}
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// Process en/decryption all the way to the last block. It takes both
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// For input it takes the ibuffer which is wrapped in 'buffer' and 'src'
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// from doFinal.
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void doLastBlock(ByteBuffer buffer, ByteBuffer src, ByteBuffer dst)
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throws IllegalBlockSizeException {
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if (buffer != null && buffer.remaining() > 0) {
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// en/decrypt on how much buffer there is in AES_BLOCK_SIZE
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processed += gctrPAndC.update(buffer, dst);
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// Process the remainder in the buffer
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if (buffer.remaining() > 0) {
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// Copy the remainder of the buffer into the extra block
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byte[] block = new byte[AES_BLOCK_SIZE];
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int over = buffer.remaining();
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int len = over; // how much is processed by in the extra block
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buffer.get(block, 0, over);
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// if src is empty, update the final block and wait for later
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// to finalize operation
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if (src.remaining() > 0) {
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// Fill out block with what is in data
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if (src.remaining() > AES_BLOCK_SIZE - over) {
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src.get(block, over, AES_BLOCK_SIZE - over);
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len += AES_BLOCK_SIZE - over;
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} else {
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// If the remaining in buffer + data does not fill a
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// block, complete the ghash operation
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int l = src.remaining();
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src.get(block, over, l);
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len += l;
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}
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}
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gctrPAndC.update(block, 0, AES_BLOCK_SIZE, dst);
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processed += len;
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}
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}
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// en/decrypt whatever remains in src.
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// If src has been consumed, this will be a no-op
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processed += gctrPAndC.doFinal(src, dst);
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}
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/*
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* This method is for CipherCore to insert the remainder of its buffer
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* into the ibuffer before a doFinal(ByteBuffer, ByteBuffer) operation
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*/
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int encrypt(byte[] in, int inOfs, int len) {
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if (len > 0) {
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// store internally until encryptFinal
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ArrayUtil.nullAndBoundsCheck(in, inOfs, len);
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if (ibuffer == null) {
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ibuffer = new ByteArrayOutputStream();
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}
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ibuffer.write(in, inOfs, len);
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}
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return len;
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}
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/**
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* Performs encryption operation.
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@ -436,32 +514,93 @@ final class GaloisCounterMode extends FeedbackCipher {
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*
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* @param in the buffer with the input data to be encrypted
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* @param inOfs the offset in <code>in</code>
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* @param len the length of the input data
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* @param inLen the length of the input data
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* @param out the buffer for the result
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* @param outOfs the offset in <code>out</code>
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* @exception ProviderException if <code>len</code> is not
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* a multiple of the block size
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* @return the number of bytes placed into the <code>out</code> buffer
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*/
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int encrypt(byte[] in, int inOfs, int len, byte[] out, int outOfs) {
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ArrayUtil.blockSizeCheck(len, blockSize);
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checkDataLength(processed, len);
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int encrypt(byte[] in, int inOfs, int inLen, byte[] out, int outOfs) {
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checkDataLength(inLen, getBufferedLength());
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ArrayUtil.nullAndBoundsCheck(in, inOfs, inLen);
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ArrayUtil.nullAndBoundsCheck(out, outOfs, inLen);
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processAAD();
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// 'inLen' stores the length to use with buffer 'in'.
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// 'len' stores the length returned by the method.
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int len = inLen;
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if (len > 0) {
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ArrayUtil.nullAndBoundsCheck(in, inOfs, len);
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ArrayUtil.nullAndBoundsCheck(out, outOfs, len);
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// if there is enough data in the ibuffer and 'in', encrypt it.
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if (ibuffer != null && ibuffer.size() > 0) {
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byte[] buffer = ibuffer.toByteArray();
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// number of bytes not filling a block
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int remainder = ibuffer.size() % blockSize;
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// number of bytes along block boundary
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int blen = ibuffer.size() - remainder;
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gctrPAndC.update(in, inOfs, len, out, outOfs);
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processed += len;
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ghashAllToS.update(out, outOfs, len);
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// If there is enough bytes in ibuffer for a block or more,
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// encrypt that first.
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if (blen > 0) {
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encryptBlocks(buffer, 0, blen, out, outOfs);
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outOfs += blen;
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}
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// blen is now the offset for 'buffer'
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// Construct and encrypt a block if there is enough 'buffer' and
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// 'in' to make one
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if ((inLen + remainder) >= blockSize) {
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byte[] block = new byte[blockSize];
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System.arraycopy(buffer, blen, block, 0, remainder);
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int inLenUsed = blockSize - remainder;
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System.arraycopy(in, inOfs, block, remainder, inLenUsed);
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encryptBlocks(block, 0, blockSize, out, outOfs);
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inOfs += inLenUsed;
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inLen -= inLenUsed;
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len += (blockSize - inLenUsed);
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outOfs += blockSize;
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ibuffer.reset();
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// Code below will write the remainder from 'in' to ibuffer
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} else if (remainder > 0) {
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// If a block or more was encrypted from 'buffer' only, but the
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// rest of 'buffer' with 'in' could not construct a block, then
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// put the rest of 'buffer' back into ibuffer.
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ibuffer.reset();
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ibuffer.write(buffer, blen, remainder);
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// Code below will write the remainder from 'in' to ibuffer
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}
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// If blen == 0 and there was not enough to construct a block
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// from 'buffer' and 'in', then let the below code append 'in' to
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// the ibuffer.
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}
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// Write any remaining bytes outside the blockSize into ibuffer.
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int remainder = inLen % blockSize;
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if (remainder > 0) {
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if (ibuffer == null) {
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ibuffer = new ByteArrayOutputStream(inLen % blockSize);
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}
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len -= remainder;
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inLen -= remainder;
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// remainder offset is based on original buffer length
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ibuffer.write(in, inOfs + inLen, remainder);
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}
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// Encrypt the remaining blocks inside of 'in'
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if (inLen > 0) {
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encryptBlocks(in, inOfs, inLen, out, outOfs);
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}
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return len;
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}
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void encryptBlocks(byte[] in, int inOfs, int len, byte[] out, int outOfs) {
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gctrPAndC.update(in, inOfs, len, out, outOfs);
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processed += len;
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ghashAllToS.update(out, outOfs, len);
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}
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/**
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* Performs encryption operation for the last time.
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*
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*/
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int encryptFinal(byte[] in, int inOfs, int len, byte[] out, int outOfs)
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throws IllegalBlockSizeException, ShortBufferException {
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if (len > MAX_BUF_SIZE - tagLenBytes) {
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throw new ShortBufferException
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("Can't fit both data and tag into one buffer");
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}
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checkDataLength(len, getBufferedLength(), tagLenBytes);
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try {
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ArrayUtil.nullAndBoundsCheck(out, outOfs,
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(len + tagLenBytes));
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throw new ShortBufferException("Output buffer too small");
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}
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checkDataLength(processed, len);
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processAAD();
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if (len > 0) {
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ArrayUtil.nullAndBoundsCheck(in, inOfs, len);
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doLastBlock(in, inOfs, len, out, outOfs, true);
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}
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byte[] lengthBlock =
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getLengthBlock(sizeOfAAD, processed);
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ghashAllToS.update(lengthBlock);
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byte[] s = ghashAllToS.digest();
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byte[] sOut = new byte[s.length];
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byte[] block = getLengthBlock(sizeOfAAD, processed);
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ghashAllToS.update(block);
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block = ghashAllToS.digest();
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GCTR gctrForSToTag = new GCTR(embeddedCipher, this.preCounterBlock);
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gctrForSToTag.doFinal(s, 0, s.length, sOut, 0);
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gctrForSToTag.doFinal(block, 0, tagLenBytes, block, 0);
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System.arraycopy(block, 0, out, (outOfs + len), tagLenBytes);
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return (len + tagLenBytes);
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}
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int encryptFinal(ByteBuffer src, ByteBuffer dst)
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throws IllegalBlockSizeException, ShortBufferException {
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dst = overlapDetection(src, dst);
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int len = src.remaining();
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len += getBufferedLength();
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// 'len' includes ibuffer data
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checkDataLength(len, tagLenBytes);
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dst.mark();
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if (dst.remaining() < len + tagLenBytes) {
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throw new ShortBufferException("Output buffer too small");
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}
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processAAD();
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if (len > 0) {
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doLastBlock((ibuffer == null || ibuffer.size() == 0) ?
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null : ByteBuffer.wrap(ibuffer.toByteArray()), src, dst);
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dst.reset();
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ghashAllToS.doLastBlock(dst, len);
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}
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byte[] block = getLengthBlock(sizeOfAAD, processed);
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ghashAllToS.update(block);
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block = ghashAllToS.digest();
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GCTR gctrForSToTag = new GCTR(embeddedCipher, this.preCounterBlock);
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gctrForSToTag.doFinal(block, 0, tagLenBytes, block, 0);
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dst.put(block, 0, tagLenBytes);
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restoreDst(dst);
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System.arraycopy(sOut, 0, out, (outOfs + len), tagLenBytes);
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return (len + tagLenBytes);
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}
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* @return the number of bytes placed into the <code>out</code> buffer
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*/
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int decrypt(byte[] in, int inOfs, int len, byte[] out, int outOfs) {
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ArrayUtil.blockSizeCheck(len, blockSize);
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checkDataLength(ibuffer.size(), len);
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processAAD();
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if (len > 0) {
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return 0;
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}
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int decrypt(ByteBuffer src, ByteBuffer dst) {
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if (src.remaining() > 0) {
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byte[] b = new byte[src.remaining()];
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src.get(b);
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try {
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ibuffer.write(b);
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} catch (IOException e) {
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throw new ProviderException("Unable to add remaining input to the buffer", e);
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}
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}
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return 0;
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}
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/**
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* Performs decryption operation for the last time.
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*
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// do this check here can also catch the potential integer overflow
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// scenario for the subsequent output buffer capacity check.
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checkDataLength(ibuffer.size(), (len - tagLenBytes));
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checkDataLength(getBufferedLength(), (len - tagLenBytes));
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try {
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ArrayUtil.nullAndBoundsCheck(out, outOfs,
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(ibuffer.size() + len) - tagLenBytes);
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(getBufferedLength() + len) - tagLenBytes);
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} catch (ArrayIndexOutOfBoundsException aiobe) {
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throw new ShortBufferException("Output buffer too small");
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}
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// If decryption is in-place or there is buffered "ibuffer" data, copy
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// the "in" byte array into the ibuffer before proceeding.
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if (in == out || ibuffer.size() > 0) {
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if (in == out || getBufferedLength() > 0) {
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if (len > 0) {
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ibuffer.write(in, inOfs, len);
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}
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doLastBlock(in, inOfs, len, out, outOfs, false);
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}
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byte[] lengthBlock =
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getLengthBlock(sizeOfAAD, processed);
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ghashAllToS.update(lengthBlock);
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byte[] s = ghashAllToS.digest();
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byte[] sOut = new byte[s.length];
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byte[] block = getLengthBlock(sizeOfAAD, processed);
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ghashAllToS.update(block);
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block = ghashAllToS.digest();
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GCTR gctrForSToTag = new GCTR(embeddedCipher, this.preCounterBlock);
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gctrForSToTag.doFinal(s, 0, s.length, sOut, 0);
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gctrForSToTag.doFinal(block, 0, tagLenBytes, block, 0);
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// check entire authentication tag for time-consistency
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int mismatch = 0;
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for (int i = 0; i < tagLenBytes; i++) {
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mismatch |= tag[i] ^ sOut[i];
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mismatch |= tag[i] ^ block[i];
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}
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if (mismatch != 0) {
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@ -624,6 +795,122 @@ final class GaloisCounterMode extends FeedbackCipher {
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return len;
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}
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// Note: In-place operations do not need an intermediary copy because
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// the GHASH check was performed before the decryption.
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int decryptFinal(ByteBuffer src, ByteBuffer dst)
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throws IllegalBlockSizeException, AEADBadTagException,
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ShortBufferException {
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dst = overlapDetection(src, dst);
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// Length of the input
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ByteBuffer tag;
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ByteBuffer ct = src.duplicate();
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ByteBuffer buffer = ((ibuffer == null || ibuffer.size() == 0) ? null :
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ByteBuffer.wrap(ibuffer.toByteArray()));
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int len;
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if (ct.remaining() >= tagLenBytes) {
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tag = src.duplicate();
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tag.position(ct.limit() - tagLenBytes);
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ct.limit(ct.limit() - tagLenBytes);
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len = ct.remaining();
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if (buffer != null) {
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len += buffer.remaining();
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}
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} else if (buffer != null && ct.remaining() < tagLenBytes) {
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// It's unlikely the tag will be between the buffer and data
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tag = ByteBuffer.allocate(tagLenBytes);
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int limit = buffer.remaining() - (tagLenBytes - ct.remaining());
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buffer.mark();
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buffer.position(limit);
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// Read from "new" limit to buffer's end
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tag.put(buffer);
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// reset buffer to data only
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buffer.reset();
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buffer.limit(limit);
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tag.put(ct);
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tag.flip();
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// Limit is how much of the ibuffer has been chopped off.
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len = buffer.remaining();
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} else {
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throw new AEADBadTagException("Input too short - need tag");
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}
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// 'len' contains the length in ibuffer and src
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checkDataLength(len);
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if (len > dst.remaining()) {
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throw new ShortBufferException("Output buffer too small");
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}
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processAAD();
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// Set the mark for a later reset. Either it will be zero, or the tag
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// buffer creation above will have consume some or all of it.
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ct.mark();
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// If there is data stored in the buffer
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if (buffer != null && buffer.remaining() > 0) {
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ghashAllToS.update(buffer, buffer.remaining());
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// Process the overage
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if (buffer.remaining() > 0) {
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// Fill out block between two buffers
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if (ct.remaining() > 0) {
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int over = buffer.remaining();
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byte[] block = new byte[AES_BLOCK_SIZE];
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// Copy the remainder of the buffer into the extra block
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buffer.get(block, 0, over);
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||||
|
||||
// Fill out block with what is in data
|
||||
if (ct.remaining() > AES_BLOCK_SIZE - over) {
|
||||
ct.get(block, over, AES_BLOCK_SIZE - over);
|
||||
ghashAllToS.update(block, 0, AES_BLOCK_SIZE);
|
||||
} else {
|
||||
// If the remaining in buffer + data does not fill a
|
||||
// block, complete the ghash operation
|
||||
int l = ct.remaining();
|
||||
ct.get(block, over, l);
|
||||
ghashAllToS.doLastBlock(ByteBuffer.wrap(block), over + l);
|
||||
}
|
||||
} else {
|
||||
// data is empty, so complete the ghash op with the
|
||||
// remaining buffer
|
||||
ghashAllToS.doLastBlock(buffer, buffer.remaining());
|
||||
}
|
||||
}
|
||||
// Prepare buffer for decryption
|
||||
buffer.flip();
|
||||
}
|
||||
|
||||
if (ct.remaining() > 0) {
|
||||
ghashAllToS.doLastBlock(ct, ct.remaining());
|
||||
}
|
||||
// Prepare buffer for decryption if available
|
||||
ct.reset();
|
||||
|
||||
byte[] block = getLengthBlock(sizeOfAAD, len);
|
||||
ghashAllToS.update(block);
|
||||
block = ghashAllToS.digest();
|
||||
GCTR gctrForSToTag = new GCTR(embeddedCipher, this.preCounterBlock);
|
||||
gctrForSToTag.doFinal(block, 0, tagLenBytes, block, 0);
|
||||
|
||||
// check entire authentication tag for time-consistency
|
||||
int mismatch = 0;
|
||||
for (int i = 0; i < tagLenBytes; i++) {
|
||||
mismatch |= tag.get() ^ block[i];
|
||||
}
|
||||
|
||||
if (mismatch != 0) {
|
||||
throw new AEADBadTagException("Tag mismatch!");
|
||||
}
|
||||
|
||||
// Decrypt the all the input data and put it into dst
|
||||
doLastBlock(buffer, ct, dst);
|
||||
restoreDst(dst);
|
||||
// 'processed' from the gctr decryption operation, not ghash
|
||||
return processed;
|
||||
}
|
||||
|
||||
// return tag length in bytes
|
||||
int getTagLen() {
|
||||
return this.tagLenBytes;
|
||||
|
@ -636,4 +923,94 @@ final class GaloisCounterMode extends FeedbackCipher {
|
|||
return ibuffer.size();
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Check for overlap. If the src and dst buffers are using shared data and
|
||||
* if dst will overwrite src data before src can be processed. If so, make
|
||||
* a copy to put the dst data in.
|
||||
*/
|
||||
ByteBuffer overlapDetection(ByteBuffer src, ByteBuffer dst) {
|
||||
if (src.isDirect() && dst.isDirect()) {
|
||||
DirectBuffer dsrc = (DirectBuffer) src;
|
||||
DirectBuffer ddst = (DirectBuffer) dst;
|
||||
|
||||
// Get the current memory address for the given ByteBuffers
|
||||
long srcaddr = dsrc.address();
|
||||
long dstaddr = ddst.address();
|
||||
|
||||
// Find the lowest attachment that is the base memory address of the
|
||||
// shared memory for the src object
|
||||
while (dsrc.attachment() != null) {
|
||||
srcaddr = ((DirectBuffer) dsrc.attachment()).address();
|
||||
dsrc = (DirectBuffer) dsrc.attachment();
|
||||
}
|
||||
|
||||
// Find the lowest attachment that is the base memory address of the
|
||||
// shared memory for the dst object
|
||||
while (ddst.attachment() != null) {
|
||||
dstaddr = ((DirectBuffer) ddst.attachment()).address();
|
||||
ddst = (DirectBuffer) ddst.attachment();
|
||||
}
|
||||
|
||||
// If the base addresses are not the same, there is no overlap
|
||||
if (srcaddr != dstaddr) {
|
||||
return dst;
|
||||
}
|
||||
// At this point we know these objects share the same memory.
|
||||
// This checks the starting position of the src and dst address for
|
||||
// overlap.
|
||||
// It uses the base address minus the passed object's address to get
|
||||
// the offset from the base address, then add the position() from
|
||||
// the passed object. That gives up the true offset from the base
|
||||
// address. As long as the src side is >= the dst side, we are not
|
||||
// in overlap.
|
||||
if (((DirectBuffer) src).address() - srcaddr + src.position() >=
|
||||
((DirectBuffer) dst).address() - dstaddr + dst.position()) {
|
||||
return dst;
|
||||
}
|
||||
|
||||
} else if (!src.isDirect() && !dst.isDirect()) {
|
||||
if (!src.isReadOnly()) {
|
||||
// If using the heap, check underlying byte[] address.
|
||||
if (!src.array().equals(dst.array()) ) {
|
||||
return dst;
|
||||
}
|
||||
|
||||
// Position plus arrayOffset() will give us the true offset from
|
||||
// the underlying byte[] address.
|
||||
if (src.position() + src.arrayOffset() >=
|
||||
dst.position() + dst.arrayOffset()) {
|
||||
return dst;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
// buffer types aren't the same
|
||||
return dst;
|
||||
}
|
||||
|
||||
// Create a copy
|
||||
ByteBuffer tmp = dst.duplicate();
|
||||
// We can use a heap buffer for internal use, save on alloc cost
|
||||
ByteBuffer bb = ByteBuffer.allocate(dst.remaining());
|
||||
tmp.limit(dst.limit());
|
||||
tmp.position(dst.position());
|
||||
bb.put(tmp);
|
||||
bb.flip();
|
||||
originalDst = dst;
|
||||
return bb;
|
||||
}
|
||||
|
||||
/**
|
||||
* If originalDst exists, dst is an internal dst buffer, then copy the data
|
||||
* into the original dst buffer
|
||||
*/
|
||||
void restoreDst(ByteBuffer dst) {
|
||||
if (originalDst == null) {
|
||||
return;
|
||||
}
|
||||
|
||||
dst.flip();
|
||||
originalDst.put(dst);
|
||||
originalDst = null;
|
||||
}
|
||||
}
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue