// Sebastien Pouliot (sebastien@ximian.com)
//
// Portions (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
-// (C) 2004 Novell (http://www.novell.com)
+// Copyright (C) 2004-2005, 2007 Novell, Inc (http://www.novell.com)
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
-using System;
using System.Globalization;
using System.IO;
using System.Runtime.InteropServices;
namespace System.Security.Cryptography {
+ [ComVisible (true)]
public class CryptoStream : Stream {
private Stream _stream;
private ICryptoTransform _transform;
private CryptoStreamMode _mode;
- private byte[] _previousBlock;
private byte[] _currentBlock;
private bool _disposed;
private bool _flushedFinalBlock;
- private int _blockSize;
private int _partialCount;
private bool _endOfStream;
-
+
private byte[] _waitingBlock;
private int _waitingCount;
-
+
private byte[] _transformedBlock;
private int _transformedPos;
private int _transformedCount;
-
+
private byte[] _workingBlock;
private int _workingCount;
public CryptoStream (Stream stream, ICryptoTransform transform, CryptoStreamMode mode)
{
- if ((mode == CryptoStreamMode.Read) && (!stream.CanRead)) {
- throw new ArgumentException (
- Locale.GetText ("Can't read on stream"));
- }
- if ((mode == CryptoStreamMode.Write) && (!stream.CanWrite)) {
- throw new ArgumentException (
- Locale.GetText ("Can't write on stream"));
+ if (mode == CryptoStreamMode.Read) {
+ if (!stream.CanRead)
+ throw new ArgumentException (Locale.GetText ("Can't read on stream"));
+ } else if (mode == CryptoStreamMode.Write) {
+ if (!stream.CanWrite)
+ throw new ArgumentException (Locale.GetText ("Can't write on stream"));
+ } else {
+ throw new ArgumentException ("mode");
}
_stream = stream;
_transform = transform;
_mode = mode;
_disposed = false;
if (transform != null) {
- if (mode == CryptoStreamMode.Read)
- _blockSize = transform.InputBlockSize;
- else if (mode == CryptoStreamMode.Write)
- _blockSize = transform.OutputBlockSize;
- _workingBlock = new byte [_blockSize];
- _currentBlock = new byte [_blockSize];
+ if (mode == CryptoStreamMode.Read) {
+ _currentBlock = new byte [transform.InputBlockSize];
+ _workingBlock = new byte [transform.InputBlockSize];
+ }
+ else if (mode == CryptoStreamMode.Write) {
+ _currentBlock = new byte [transform.OutputBlockSize];
+ _workingBlock = new byte [transform.OutputBlockSize];
+ }
}
}
-
+
~CryptoStream ()
{
Dispose (false);
public override bool CanRead {
get { return (_mode == CryptoStreamMode.Read); }
}
-
+
public override bool CanSeek {
get { return false; }
}
-
+
public override bool CanWrite {
get { return (_mode == CryptoStreamMode.Write); }
}
public override long Length {
get { throw new NotSupportedException ("Length"); }
}
-
+
public override long Position {
get { throw new NotSupportedException ("Position"); }
set { throw new NotSupportedException ("Position"); }
}
-
+
public void Clear ()
{
- Dispose (true);
- GC.SuppressFinalize (this); // not called in Stream.Dispose
+ Close ();
}
-
+
// LAMESPEC: A CryptoStream can be close in read mode
public override void Close ()
{
- // only flush in write mode (bugzilla 46143)
- if ((!_flushedFinalBlock) && (_mode == CryptoStreamMode.Write))
- FlushFinalBlock ();
-
- if (_stream != null)
- _stream.Close ();
+ base.Close ();
}
-
+
public override int Read ([In,Out] byte[] buffer, int offset, int count)
{
if (_mode != CryptoStreamMode.Read) {
}
// yes - buffer.Length will throw a NullReferenceException if buffer is null
// but by doing so we match MS implementation
- if (offset + count > buffer.Length) {
+ // re-ordered to avoid integer overflow
+ if (offset > buffer.Length - count) {
throw new ArgumentException ("(offset+count)",
Locale.GetText ("buffer overflow"));
}
- // for some strange reason Object_disposedException isn't throw
- // instead we get a ArgumentNullException (probably from an internal method)
+ // for some strange reason ObjectDisposedException isn't throw
if (_workingBlock == null) {
- throw new ArgumentNullException (
- Locale.GetText ("object _disposed"));
+ return 0;
}
-
+
int result = 0;
if ((count == 0) || ((_transformedPos == _transformedCount) && (_endOfStream)))
return result;
-
+
if (_waitingBlock == null) {
- _transformedBlock = new byte [_blockSize << 2];
+ _transformedBlock = new byte [_transform.OutputBlockSize << 2];
_transformedPos = 0;
_transformedCount = 0;
- _waitingBlock = new byte [_blockSize];
+ _waitingBlock = new byte [_transform.InputBlockSize];
_waitingCount = _stream.Read (_waitingBlock, 0, _waitingBlock.Length);
}
while (count > 0) {
// transformed but not yet returned
int length = (_transformedCount - _transformedPos);
-
+
// need more data - at least one full block must be available if we haven't reach the end of the stream
- if (length < _blockSize) {
+ if (length < _transform.InputBlockSize) {
int transformed = 0;
-
+
// load a new block
- _workingCount = _stream.Read (_workingBlock, 0, _workingBlock.Length);
- _endOfStream = (_workingCount < _blockSize);
-
+ _workingCount = _stream.Read (_workingBlock, 0, _transform.InputBlockSize);
+ _endOfStream = (_workingCount < _transform.InputBlockSize);
+
if (!_endOfStream) {
// transform the waiting block
transformed = _transform.TransformBlock (_waitingBlock, 0, _waitingBlock.Length, _transformedBlock, _transformedCount);
-
+
// transfer temporary to waiting
Buffer.BlockCopy (_workingBlock, 0, _waitingBlock, 0, _workingCount);
_waitingCount = _workingCount;
if (_workingCount > 0) {
// transform the waiting block
transformed = _transform.TransformBlock (_waitingBlock, 0, _waitingBlock.Length, _transformedBlock, _transformedCount);
-
+
// transfer temporary to waiting
Buffer.BlockCopy (_workingBlock, 0, _waitingBlock, 0, _workingCount);
_waitingCount = _workingCount;
-
+
length += transformed;
_transformedCount += transformed;
}
- byte[] input = _transform.TransformFinalBlock (_waitingBlock, 0, _waitingCount);
- transformed = input.Length;
- Array.Copy (input, 0, _transformedBlock, _transformedCount, input.Length);
- // zeroize this last block
- Array.Clear (input, 0, input.Length);
+ if (!_flushedFinalBlock) {
+ byte[] input = _transform.TransformFinalBlock (_waitingBlock, 0, _waitingCount);
+ transformed = input.Length;
+ Buffer.BlockCopy (input, 0, _transformedBlock, _transformedCount, input.Length);
+ // zeroize this last block
+ Array.Clear (input, 0, input.Length);
+ _flushedFinalBlock = true;
+ }
}
-
+
length += transformed;
_transformedCount += transformed;
}
// compaction
- if (_transformedPos > _blockSize) {
+ if (_transformedPos > _transform.OutputBlockSize) {
Buffer.BlockCopy (_transformedBlock, _transformedPos, _transformedBlock, 0, length);
_transformedCount -= _transformedPos;
_transformedPos = 0;
}
-
+
length = ((count < length) ? count : length);
- Buffer.BlockCopy (_transformedBlock, _transformedPos, buffer, offset, length);
- _transformedPos += length;
-
- result += length;
- offset += length;
- count -= length;
-
+ if (length > 0) {
+ Buffer.BlockCopy (_transformedBlock, _transformedPos, buffer, offset, length);
+ _transformedPos += length;
+
+ result += length;
+ offset += length;
+ count -= length;
+ }
+
// there may not be enough data in the stream for a
// complete block
- if ((length != _blockSize) || (_endOfStream)) {
+ if (((length != _transform.InputBlockSize) && (_waitingCount != _transform.InputBlockSize)) || (_endOfStream)) {
count = 0; // no more data can be read
}
}
return result;
}
-
+
public override void Write (byte[] buffer, int offset, int count)
{
if (_mode != CryptoStreamMode.Write) {
throw new ArgumentOutOfRangeException ("count",
Locale.GetText ("negative"));
}
- if (offset + count > buffer.Length) {
+ // re-ordered to avoid integer overflow
+ if (offset > buffer.Length - count) {
throw new ArgumentException ("(offset+count)",
Locale.GetText ("buffer overflow"));
}
-
+
+ if (_stream == null)
+ throw new ArgumentNullException ("inner stream was diposed");
+
+ int buffer_length = count;
+
// partial block (in progress)
- if ((_partialCount > 0) && (_partialCount != _blockSize)) {
- int remainder = _blockSize - _partialCount;
+ if ((_partialCount > 0) && (_partialCount != _transform.InputBlockSize)) {
+ int remainder = _transform.InputBlockSize - _partialCount;
remainder = ((count < remainder) ? count : remainder);
Buffer.BlockCopy (buffer, offset, _workingBlock, _partialCount, remainder);
_partialCount += remainder;
offset += remainder;
count -= remainder;
}
-
+
int bufferPos = offset;
while (count > 0) {
- if (_partialCount == _blockSize) {
- _partialCount = 0;
+ if (_partialCount == _transform.InputBlockSize) {
// use partial block to avoid (re)allocation
- _transform.TransformBlock (_workingBlock, 0, _blockSize, _currentBlock, 0);
- _stream.Write (_currentBlock, 0, _currentBlock.Length);
+ int len = _transform.TransformBlock (_workingBlock, 0, _partialCount, _currentBlock, 0);
+ _stream.Write (_currentBlock, 0, len);
+ // reset
+ _partialCount = 0;
}
-
+
if (_transform.CanTransformMultipleBlocks) {
- // transform all except the last block (which may be the last block
- // of the stream and require TransformFinalBlock)
- int numBlock = ((_partialCount + count) / _blockSize);
- if (((_partialCount + count) % _blockSize) == 0) // partial block ?
- numBlock--; // no then reduce
- int multiSize = (numBlock * _blockSize);
- if (numBlock > 0) {
- byte[] multiBlocks = new byte [multiSize];
- _transform.TransformBlock (buffer, offset, multiSize, multiBlocks, 0);
- _stream.Write (multiBlocks, 0, multiSize);
- // copy last block into _currentBlock
- _partialCount = count - multiSize;
- Array.Copy (buffer, offset + multiSize, _workingBlock, 0, _partialCount);
+ // get the biggest multiple of InputBlockSize in count (without mul or div)
+ int size = (count & ~(_transform.InputBlockSize - 1));
+ int rem = (count & (_transform.InputBlockSize - 1));
+ // avoid reallocating memory at each call (reuse same buffer whenever possible)
+ int sizeWorkingBlock = (1 + size / _transform.InputBlockSize) * _transform.OutputBlockSize;
+ if (_workingBlock.Length < sizeWorkingBlock) {
+ Array.Clear (_workingBlock, 0, _workingBlock.Length);
+ _workingBlock = new byte [sizeWorkingBlock];
}
- else {
- Array.Copy (buffer, offset, _workingBlock, _partialCount, count);
- _partialCount += count;
+
+ if (size > 0) {
+ int len = _transform.TransformBlock (buffer, offset, size, _workingBlock, 0);
+ _stream.Write (_workingBlock, 0, len);
}
+
+ if (rem > 0)
+ Buffer.BlockCopy (buffer, buffer_length - rem, _workingBlock, 0, rem);
+ _partialCount = rem;
count = 0; // the last block, if any, is in _workingBlock
- }
- else {
- int len = Math.Min (_blockSize - _partialCount, count);
- Array.Copy (buffer, bufferPos, _workingBlock, _partialCount, len);
+ } else {
+ int len = Math.Min (_transform.InputBlockSize - _partialCount, count);
+ Buffer.BlockCopy (buffer, bufferPos, _workingBlock, _partialCount, len);
bufferPos += len;
_partialCount += len;
count -= len;
}
}
}
-
+
public override void Flush ()
{
- if (_stream != null)
- _stream.Flush ();
}
-
+
public void FlushFinalBlock ()
{
- if (_flushedFinalBlock) {
- throw new NotSupportedException (
- Locale.GetText ("This method cannot be called twice."));
- }
- if (_mode != CryptoStreamMode.Write) {
- throw new NotSupportedException (
- Locale.GetText ("cannot flush a non-writeable CryptoStream"));
- }
-
+ if (_flushedFinalBlock)
+ throw new NotSupportedException (Locale.GetText ("This method cannot be called twice."));
+ if (_disposed)
+ throw new NotSupportedException (Locale.GetText ("CryptoStream was disposed."));
+
_flushedFinalBlock = true;
byte[] finalBuffer = _transform.TransformFinalBlock (_workingBlock, 0, _partialCount);
- if (_stream != null) {
+ if (_stream != null && _mode == CryptoStreamMode.Write) {
_stream.Write (finalBuffer, 0, finalBuffer.Length);
+ }
+ if (_stream is CryptoStream) {
+ // for cascading crypto streams
+ (_stream as CryptoStream).FlushFinalBlock ();
+ } else {
_stream.Flush ();
}
// zeroize
Array.Clear (finalBuffer, 0, finalBuffer.Length);
}
-
+
public override long Seek (long offset, SeekOrigin origin)
{
throw new NotSupportedException ("Seek");
{
throw new NotSupportedException ("SetLength");
}
-
- protected virtual void Dispose (bool disposing)
+
+ protected override void Dispose (bool disposing)
{
if (!_disposed) {
+ if (disposing) {
+ if (!_flushedFinalBlock) {
+ FlushFinalBlock ();
+ }
+
+ if (_stream != null)
+ _stream.Close ();
+ }
_disposed = true;
// always cleared for security reason
if (_workingBlock != null)
Array.Clear (_workingBlock, 0, _workingBlock.Length);
if (_currentBlock != null)
Array.Clear (_currentBlock, 0, _currentBlock.Length);
- if (_previousBlock != null)
- Array.Clear (_previousBlock, 0, _previousBlock.Length);
if (disposing) {
_stream = null;
_workingBlock = null;
_currentBlock = null;
- _previousBlock = null;
}
}
}
projects / mono.git / blobdiff