// DeflaterOutputStream.cs
//
// Copyright (C) 2001 Mike Krueger
//
// This file was translated from java, it was part of the GNU Classpath
// Copyright (C) 2001 Free Software Foundation, Inc.
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// Linking this library statically or dynamically with other modules is
// making a combined work based on this library. Thus, the terms and
// conditions of the GNU General Public License cover the whole
// combination.
//
// As a special exception, the copyright holders of this library give you
// permission to link this library with independent modules to produce an
// executable, regardless of the license terms of these independent
// modules, and to copy and distribute the resulting executable under
// terms of your choice, provided that you also meet, for each linked
// independent module, the terms and conditions of the license of that
// module. An independent module is a module which is not derived from
// or based on this library. If you modify this library, you may extend
// this exception to your version of the library, but you are not
// obligated to do so. If you do not wish to do so, delete this
// exception statement from your version.
// HISTORY
// 22-12-2009 DavidPierson Added AES support
using System;
using System.IO;
#if !NETCF_1_0
using System.Security.Cryptography;
using CommonMPQ.SharpZipLib.Encryption;
#endif
namespace CommonMPQ.SharpZipLib.Zip.Compression.Streams
{
/// <summary>
/// A special stream deflating or compressing the bytes that are
/// written to it. It uses a Deflater to perform actual deflating.<br/>
/// Authors of the original java version : Tom Tromey, Jochen Hoenicke
/// </summary>
public class DeflaterOutputStream : Stream
{
#region Constructors
/// <summary>
/// Creates a new DeflaterOutputStream with a default Deflater and default buffer size.
/// </summary>
/// <param name="baseOutputStream">
/// the output stream where deflated output should be written.
/// </param>
public DeflaterOutputStream(Stream baseOutputStream)
: this(baseOutputStream, new Deflater(), 512)
{
}
/// <summary>
/// Creates a new DeflaterOutputStream with the given Deflater and
/// default buffer size.
/// </summary>
/// <param name="baseOutputStream">
/// the output stream where deflated output should be written.
/// </param>
/// <param name="deflater">
/// the underlying deflater.
/// </param>
public DeflaterOutputStream(Stream baseOutputStream, Deflater deflater)
: this(baseOutputStream, deflater, 512)
{
}
/// <summary>
/// Creates a new DeflaterOutputStream with the given Deflater and
/// buffer size.
/// </summary>
/// <param name="baseOutputStream">
/// The output stream where deflated output is written.
/// </param>
/// <param name="deflater">
/// The underlying deflater to use
/// </param>
/// <param name="bufferSize">
/// The buffer size in bytes to use when deflating (minimum value 512)
/// </param>
/// <exception cref="ArgumentOutOfRangeException">
/// bufsize is less than or equal to zero.
/// </exception>
/// <exception cref="ArgumentException">
/// baseOutputStream does not support writing
/// </exception>
/// <exception cref="ArgumentNullException">
/// deflater instance is null
/// </exception>
public DeflaterOutputStream(Stream baseOutputStream, Deflater deflater, int bufferSize)
{
if ( baseOutputStream == null ) {
throw new ArgumentNullException("baseOutputStream");
}
if (baseOutputStream.CanWrite == false) {
throw new ArgumentException("Must support writing", "baseOutputStream");
}
if (deflater == null) {
throw new ArgumentNullException("deflater");
}
if (bufferSize < 512) {
throw new ArgumentOutOfRangeException("bufferSize");
}
baseOutputStream_ = baseOutputStream;
buffer_ = new byte[bufferSize];
deflater_ = deflater;
}
#endregion
#region Public API
/// <summary>
/// Finishes the stream by calling finish() on the deflater.
/// </summary>
/// <exception cref="SharpZipBaseException">
/// Not all input is deflated
/// </exception>
public virtual void Finish()
{
deflater_.Finish();
while (!deflater_.IsFinished) {
int len = deflater_.Deflate(buffer_, 0, buffer_.Length);
if (len <= 0) {
break;
}
#if NETCF_1_0
if ( keys != null ) {
#else
if (cryptoTransform_ != null) {
#endif
EncryptBlock(buffer_, 0, len);
}
baseOutputStream_.Write(buffer_, 0, len);
}
if (!deflater_.IsFinished) {
throw new SharpZipBaseException("Can't deflate all input?");
}
baseOutputStream_.Flush();
#if NETCF_1_0
if ( keys != null ) {
keys = null;
}
#else
if (cryptoTransform_ != null) {
#if !NET_1_1 && !NETCF_2_0
if (cryptoTransform_ is ZipAESTransform) {
AESAuthCode = ((ZipAESTransform)cryptoTransform_).GetAuthCode();
}
#endif
cryptoTransform_.Dispose();
cryptoTransform_ = null;
}
#endif
}
/// <summary>
/// Get/set flag indicating ownership of the underlying stream.
/// When the flag is true <see cref="Close"></see> will close the underlying stream also.
/// </summary>
public bool IsStreamOwner
{
get { return isStreamOwner_; }
set { isStreamOwner_ = value; }
}
/// <summary>
/// Allows client to determine if an entry can be patched after its added
/// </summary>
public bool CanPatchEntries {
get {
return baseOutputStream_.CanSeek;
}
}
#endregion
#region Encryption
string password;
#if NETCF_1_0
uint[] keys;
#else
ICryptoTransform cryptoTransform_;
/// <summary>
/// Returns the 10 byte AUTH CODE to be appended immediately following the AES data stream.
/// </summary>
protected byte[] AESAuthCode;
#endif
/// <summary>
/// Get/set the password used for encryption.
/// </summary>
/// <remarks>When set to null or if the password is empty no encryption is performed</remarks>
public string Password {
get {
return password;
}
set {
if ( (value != null) && (value.Length == 0) ) {
password = null;
} else {
password = value;
}
}
}
/// <summary>
/// Encrypt a block of data
/// </summary>
/// <param name="buffer">
/// Data to encrypt. NOTE the original contents of the buffer are lost
/// </param>
/// <param name="offset">
/// Offset of first byte in buffer to encrypt
/// </param>
/// <param name="length">
/// Number of bytes in buffer to encrypt
/// </param>
protected void EncryptBlock(byte[] buffer, int offset, int length)
{
#if NETCF_1_0
for (int i = offset; i < offset + length; ++i) {
byte oldbyte = buffer[i];
buffer[i] ^= EncryptByte();
UpdateKeys(oldbyte);
}
#else
cryptoTransform_.TransformBlock(buffer, 0, length, buffer, 0);
#endif
}
/// <summary>
/// Initializes encryption keys based on given <paramref name="password"/>.
/// </summary>
/// <param name="password">The password.</param>
protected void InitializePassword(string password)
{
#if NETCF_1_0
keys = new uint[] {
0x12345678,
0x23456789,
0x34567890
};
byte[] rawPassword = ZipConstants.ConvertToArray(password);
for (int i = 0; i < rawPassword.Length; ++i) {
UpdateKeys((byte)rawPassword[i]);
}
#else
PkzipClassicManaged pkManaged = new PkzipClassicManaged();
byte[] key = PkzipClassic.GenerateKeys(ZipConstants.ConvertToArray(password));
cryptoTransform_ = pkManaged.CreateEncryptor(key, null);
#endif
}
#if !NET_1_1 && !NETCF_2_0
/// <summary>
/// Initializes encryption keys based on given password.
/// </summary>
protected void InitializeAESPassword(ZipEntry entry, string rawPassword,
out byte[] salt, out byte[] pwdVerifier) {
salt = new byte[entry.AESSaltLen];
// Salt needs to be cryptographically random, and unique per file
if (_aesRnd == null)
_aesRnd = new RNGCryptoServiceProvider();
_aesRnd.GetBytes(salt);
int blockSize = entry.AESKeySize / 8; // bits to bytes
cryptoTransform_ = new ZipAESTransform(rawPassword, salt, blockSize, true);
pwdVerifier = ((ZipAESTransform)cryptoTransform_).PwdVerifier;
}
#endif
#if NETCF_1_0
/// <summary>
/// Encrypt a single byte
/// </summary>
/// <returns>
/// The encrypted value
/// </returns>
protected byte EncryptByte()
{
uint temp = ((keys[2] & 0xFFFF) | 2);
return (byte)((temp * (temp ^ 1)) >> 8);
}
/// <summary>
/// Update encryption keys
/// </summary>
protected void UpdateKeys(byte ch)
{
keys[0] = Crc32.ComputeCrc32(keys[0], ch);
keys[1] = keys[1] + (byte)keys[0];
keys[1] = keys[1] * 134775813 + 1;
keys[2] = Crc32.ComputeCrc32(keys[2], (byte)(keys[1] >> 24));
}
#endif
#endregion
#region Deflation Support
/// <summary>
/// Deflates everything in the input buffers. This will call
/// <code>def.deflate()</code> until all bytes from the input buffers
/// are processed.
/// </summary>
protected void Deflate()
{
while (!deflater_.IsNeedingInput)
{
int deflateCount = deflater_.Deflate(buffer_, 0, buffer_.Length);
if (deflateCount <= 0) {
break;
}
#if NETCF_1_0
if (keys != null)
#else
if (cryptoTransform_ != null)
#endif
{
EncryptBlock(buffer_, 0, deflateCount);
}
baseOutputStream_.Write(buffer_, 0, deflateCount);
}
if (!deflater_.IsNeedingInput) {
throw new SharpZipBaseException("DeflaterOutputStream can't deflate all input?");
}
}
#endregion
#region Stream Overrides
/// <summary>
/// Gets value indicating stream can be read from
/// </summary>
public override bool CanRead
{
get {
return false;
}
}
/// <summary>
/// Gets a value indicating if seeking is supported for this stream
/// This property always returns false
/// </summary>
public override bool CanSeek {
get {
return false;
}
}
/// <summary>
/// Get value indicating if this stream supports writing
/// </summary>
public override bool CanWrite {
get {
return baseOutputStream_.CanWrite;
}
}
/// <summary>
/// Get current length of stream
/// </summary>
public override long Length {
get {
return baseOutputStream_.Length;
}
}
/// <summary>
/// Gets the current position within the stream.
/// </summary>
/// <exception cref="NotSupportedException">Any attempt to set position</exception>
public override long Position {
get {
return baseOutputStream_.Position;
}
set {
throw new NotSupportedException("Position property not supported");
}
}
/// <summary>
/// Sets the current position of this stream to the given value. Not supported by this class!
/// </summary>
/// <param name="offset">The offset relative to the <paramref name="origin"/> to seek.</param>
/// <param name="origin">The <see cref="SeekOrigin"/> to seek from.</param>
/// <returns>The new position in the stream.</returns>
/// <exception cref="NotSupportedException">Any access</exception>
public override long Seek(long offset, SeekOrigin origin)
{
throw new NotSupportedException("DeflaterOutputStream Seek not supported");
}
/// <summary>
/// Sets the length of this stream to the given value. Not supported by this class!
/// </summary>
/// <param name="value">The new stream length.</param>
/// <exception cref="NotSupportedException">Any access</exception>
public override void SetLength(long value)
{
throw new NotSupportedException("DeflaterOutputStream SetLength not supported");
}
/// <summary>
/// Read a byte from stream advancing position by one
/// </summary>
/// <returns>The byte read cast to an int. THe value is -1 if at the end of the stream.</returns>
/// <exception cref="NotSupportedException">Any access</exception>
public override int ReadByte()
{
throw new NotSupportedException("DeflaterOutputStream ReadByte not supported");
}
/// <summary>
/// Read a block of bytes from stream
/// </summary>
/// <param name="buffer">The buffer to store read data in.</param>
/// <param name="offset">The offset to start storing at.</param>
/// <param name="count">The maximum number of bytes to read.</param>
/// <returns>The actual number of bytes read. Zero if end of stream is detected.</returns>
/// <exception cref="NotSupportedException">Any access</exception>
public override int Read(byte[] buffer, int offset, int count)
{
throw new NotSupportedException("DeflaterOutputStream Read not supported");
}
/// <summary>
/// Asynchronous reads are not supported a NotSupportedException is always thrown
/// </summary>
/// <param name="buffer">The buffer to read into.</param>
/// <param name="offset">The offset to start storing data at.</param>
/// <param name="count">The number of bytes to read</param>
/// <param name="callback">The async callback to use.</param>
/// <param name="state">The state to use.</param>
/// <returns>Returns an <see cref="IAsyncResult"/></returns>
/// <exception cref="NotSupportedException">Any access</exception>
public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, object state)
{
throw new NotSupportedException("DeflaterOutputStream BeginRead not currently supported");
}
/// <summary>
/// Asynchronous writes arent supported, a NotSupportedException is always thrown
/// </summary>
/// <param name="buffer">The buffer to write.</param>
/// <param name="offset">The offset to begin writing at.</param>
/// <param name="count">The number of bytes to write.</param>
/// <param name="callback">The <see cref="AsyncCallback"/> to use.</param>
/// <param name="state">The state object.</param>
/// <returns>Returns an IAsyncResult.</returns>
/// <exception cref="NotSupportedException">Any access</exception>
public override IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback callback, object state)
{
throw new NotSupportedException("BeginWrite is not supported");
}
/// <summary>
/// Flushes the stream by calling <see cref="DeflaterOutputStream.Flush">Flush</see> on the deflater and then
/// on the underlying stream. This ensures that all bytes are flushed.
/// </summary>
public override void Flush()
{
deflater_.Flush();
Deflate();
baseOutputStream_.Flush();
}
/// <summary>
/// Calls <see cref="Finish"/> and closes the underlying
/// stream when <see cref="IsStreamOwner"></see> is true.
/// </summary>
public override void Close()
{
if ( !isClosed_ ) {
isClosed_ = true;
try {
Finish();
#if NETCF_1_0
keys=null;
#else
if ( cryptoTransform_ != null ) {
GetAuthCodeIfAES();
cryptoTransform_.Dispose();
cryptoTransform_ = null;
}
#endif
}
finally {
if( isStreamOwner_ ) {
baseOutputStream_.Close();
}
}
}
}
private void GetAuthCodeIfAES() {
#if !NET_1_1 && !NETCF_2_0
if (cryptoTransform_ is ZipAESTransform) {
AESAuthCode = ((ZipAESTransform)cryptoTransform_).GetAuthCode();
}
#endif
}
/// <summary>
/// Writes a single byte to the compressed output stream.
/// </summary>
/// <param name="value">
/// The byte value.
/// </param>
public override void WriteByte(byte value)
{
byte[] b = new byte[1];
b[0] = value;
Write(b, 0, 1);
}
/// <summary>
/// Writes bytes from an array to the compressed stream.
/// </summary>
/// <param name="buffer">
/// The byte array
/// </param>
/// <param name="offset">
/// The offset into the byte array where to start.
/// </param>
/// <param name="count">
/// The number of bytes to write.
/// </param>
public override void Write(byte[] buffer, int offset, int count)
{
deflater_.SetInput(buffer, offset, count);
Deflate();
}
#endregion
#region Instance Fields
/// <summary>
/// This buffer is used temporarily to retrieve the bytes from the
/// deflater and write them to the underlying output stream.
/// </summary>
byte[] buffer_;
/// <summary>
/// The deflater which is used to deflate the stream.
/// </summary>
protected Deflater deflater_;
/// <summary>
/// Base stream the deflater depends on.
/// </summary>
protected Stream baseOutputStream_;
bool isClosed_;
bool isStreamOwner_ = true;
#endregion
#region Static Fields
#if !NET_1_1 && !NETCF_2_0
// Static to help ensure that multiple files within a zip will get different random salt
private static RNGCryptoServiceProvider _aesRnd;
#endif
#endregion
}
}