//#define Trace
// ZipEntry.Write.cs
// ------------------------------------------------------------------
//
// Copyright (c) 2009-2010 Dino Chiesa
// All rights reserved.
//
// This code module is part of DotNetZip, a zipfile class library.
//
// ------------------------------------------------------------------
//
// This code is licensed under the Microsoft Public License.
// See the file License.txt for the license details.
// More info on: http://dotnetzip.codeplex.com
//
// ------------------------------------------------------------------
//
// last saved (in emacs):
// Time-stamp: <2010-February-24 22:34:42>
//
// ------------------------------------------------------------------
//
// This module defines logic for writing (saving) the ZipEntry into a
// zip file.
//
//
// ------------------------------------------------------------------
using System;
using System.IO;
using RE = System.Text.RegularExpressions;
namespace Ionic.Zip
{
public partial class ZipEntry
{
internal void WriteCentralDirectoryEntry(Stream s)
{
_ConsAndWriteCentralDirectoryEntry(s);
}
private void _ConsAndWriteCentralDirectoryEntry(Stream s)
{
byte[] bytes = new byte[4096];
int i = 0;
// signature
bytes[i++] = (byte)(ZipConstants.ZipDirEntrySignature & 0x000000FF);
bytes[i++] = (byte)((ZipConstants.ZipDirEntrySignature & 0x0000FF00) >> 8);
bytes[i++] = (byte)((ZipConstants.ZipDirEntrySignature & 0x00FF0000) >> 16);
bytes[i++] = (byte)((ZipConstants.ZipDirEntrySignature & 0xFF000000) >> 24);
// Version Made By
// workitem 7071
// We must not overwrite the VersionMadeBy field when writing out a zip archive.
// The VersionMadeBy tells the zip reader the meaning of the File attributes.
// Overwriting the VersionMadeBy will result in inconsistent metadata.
// Consider the scenario where the application opens and reads a zip file that had been created
// on Linux. Then the app adds one file to the Zip archive, and saves it.
// The file attributes for all the entries added on Linux will be significant
// for Linux. Therefore the VersionMadeBy for those entries must not be changed.
// Only the entries that are actually created on Windows NTFS should get the
// VersionMadeBy indicating Windows/NTFS.
bytes[i++] = (byte)(_VersionMadeBy & 0x00FF);
bytes[i++] = (byte)((_VersionMadeBy & 0xFF00) >> 8);
// Apparently we want to duplicate the extra field here; we cannot
// simply zero it out and assume tools and apps will use the right one.
////Int16 extraFieldLengthSave = (short)(_EntryHeader[28] + _EntryHeader[29] * 256);
////_EntryHeader[28] = 0;
////_EntryHeader[29] = 0;
// Version Needed, Bitfield, compression method, lastmod,
// crc, compressed and uncompressed sizes, filename length and extra field length.
// These are all present in the local file header, but they may be zero values there.
// So we cannot just copy them.
Int16 versionNeededToExtract = (Int16)(_OutputUsesZip64.Value ? 45 : 20);
bytes[i++] = (byte)(versionNeededToExtract & 0x00FF);
bytes[i++] = (byte)((versionNeededToExtract & 0xFF00) >> 8);
bytes[i++] = (byte)(_BitField & 0x00FF);
bytes[i++] = (byte)((_BitField & 0xFF00) >> 8);
bytes[i++] = (byte)(_CompressionMethod & 0x00FF);
bytes[i++] = (byte)((_CompressionMethod & 0xFF00) >> 8);
#if AESCRYPTO
if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
i -= 2;
bytes[i++] = 0x63;
bytes[i++] = 0;
}
#endif
bytes[i++] = (byte)(_TimeBlob & 0x000000FF);
bytes[i++] = (byte)((_TimeBlob & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_TimeBlob & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_TimeBlob & 0xFF000000) >> 24);
bytes[i++] = (byte)(_Crc32 & 0x000000FF);
bytes[i++] = (byte)((_Crc32 & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_Crc32 & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_Crc32 & 0xFF000000) >> 24);
int j = 0;
if (_OutputUsesZip64.Value)
{
// CompressedSize (Int32) and UncompressedSize - all 0xFF
for (j = 0; j < 8; j++)
bytes[i++] = 0xFF;
}
else
{
bytes[i++] = (byte)(_CompressedSize & 0x000000FF);
bytes[i++] = (byte)((_CompressedSize & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_CompressedSize & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_CompressedSize & 0xFF000000) >> 24);
bytes[i++] = (byte)(_UncompressedSize & 0x000000FF);
bytes[i++] = (byte)((_UncompressedSize & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_UncompressedSize & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_UncompressedSize & 0xFF000000) >> 24);
}
byte[] FileNameBytes = _GetEncodedFileNameBytes();
Int16 filenameLength = (Int16)FileNameBytes.Length;
bytes[i++] = (byte)(filenameLength & 0x00FF);
bytes[i++] = (byte)((filenameLength & 0xFF00) >> 8);
// do this again because now we have real data
_presumeZip64 = _OutputUsesZip64.Value;
_Extra = ConstructExtraField(true);
Int16 extraFieldLength = (Int16)((_Extra == null) ? 0 : _Extra.Length);
bytes[i++] = (byte)(extraFieldLength & 0x00FF);
bytes[i++] = (byte)((extraFieldLength & 0xFF00) >> 8);
// File (entry) Comment Length
// the _CommentBytes private field was set during WriteHeader()
int commentLength = (_CommentBytes == null) ? 0 : _CommentBytes.Length;
// the size of our buffer defines the max length of the comment we can write
if (commentLength + i > bytes.Length) commentLength = bytes.Length - i;
bytes[i++] = (byte)(commentLength & 0x00FF);
bytes[i++] = (byte)((commentLength & 0xFF00) >> 8);
// Disk number start
bytes[i++] = (byte)(_diskNumber & 0x00FF);
bytes[i++] = (byte)((_diskNumber & 0xFF00) >> 8);
// internal file attrs
// workitem 7801
bytes[i++] = (byte)((_IsText) ? 1 : 0); // lo bit: filetype hint. 0=bin, 1=txt.
bytes[i++] = 0;
// external file attrs
// workitem 7071
bytes[i++] = (byte)(_ExternalFileAttrs & 0x000000FF);
bytes[i++] = (byte)((_ExternalFileAttrs & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_ExternalFileAttrs & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_ExternalFileAttrs & 0xFF000000) >> 24);
// relative offset of local header
if (_OutputUsesZip64.Value)
{
// Value==true means it used Zip64.
for (j = 0; j < 4; j++) bytes[i++] = 0xFF;
}
else
{
bytes[i++] = (byte)(_RelativeOffsetOfLocalHeader & 0x000000FF);
bytes[i++] = (byte)((_RelativeOffsetOfLocalHeader & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_RelativeOffsetOfLocalHeader & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_RelativeOffsetOfLocalHeader & 0xFF000000) >> 24);
}
// actual filename
for (j = 0; j < filenameLength; j++)
bytes[i + j] = FileNameBytes[j];
i += j;
// "Extra field"
if (_Extra != null)
{
for (j = 0; j < extraFieldLength; j++)
bytes[i + j] = _Extra[j];
i += j;
}
// file (entry) comment
if (commentLength != 0)
{
// now actually write the comment itself into the byte buffer
for (j = 0; (j < commentLength) && (i + j < bytes.Length); j++)
bytes[i + j] = _CommentBytes[j];
i += j;
}
s.Write(bytes, 0, i);
}
#if INFOZIP_UTF8
static private bool FileNameIsUtf8(char[] FileNameChars)
{
bool isUTF8 = false;
bool isUnicode = false;
for (int j = 0; j < FileNameChars.Length; j++)
{
byte[] b = System.BitConverter.GetBytes(FileNameChars[j]);
isUnicode |= (b.Length != 2);
isUnicode |= (b[1] != 0);
isUTF8 |= ((b[0] & 0x80) != 0);
}
return isUTF8;
}
#endif
private byte[] ConstructExtraField(bool forCentralDirectory)
{
var listOfBlocks = new System.Collections.Generic.List<byte[]>();
byte[] block;
// Conditionally emit an extra field with Zip64 information.
// If the Zip64 option is Always, we emit the field, before knowing that it's necessary.
// Later, if it turns out this entry does not need zip64, we'll set the header ID to rubbish and
// the data will be ignored. This results in additional overhead metadata
// in the zip file, but it will be small in comparison to the entry data.
//
// On the other hand if the Zip64 option is AsNecessary and it's NOT for the central
// directory, then we do the same thing. Or, if the Zip64 option is AsNecessary and
// it IS for the central directory, and the entry requires zip64, then emit the
// header.
if (_container.Zip64 == Zip64Option.Always ||
(_container.Zip64 == Zip64Option.AsNecessary &&
(!forCentralDirectory || _entryRequiresZip64.Value)))
{
// add extra field for zip64 here
// workitem 7924
int sz = 4 + (forCentralDirectory ? 28 : 16);
block = new byte[sz];
int i = 0;
if (_presumeZip64 || forCentralDirectory)
{
// HeaderId = always use zip64 extensions.
block[i++] = 0x01;
block[i++] = 0x00;
}
else
{
// HeaderId = dummy data now, maybe set to 0x0001 (ZIP64) later.
block[i++] = 0x99;
block[i++] = 0x99;
}
// DataSize
block[i++] = (byte)(sz - 4); // decimal 28 or 16 (workitem 7924)
block[i++] = 0x00;
// The actual metadata - we may or may not have real values yet...
// uncompressed size
Array.Copy(BitConverter.GetBytes(_UncompressedSize), 0, block, i, 8);
i += 8;
// compressed size
Array.Copy(BitConverter.GetBytes(_CompressedSize), 0, block, i, 8);
// workitem 7924 - only include this if the "extra" field is for use in the central directory.
// It is unnecessary and not useful for local header; makes WinZip choke.
if (forCentralDirectory)
{
i += 8;
// relative offset
Array.Copy(BitConverter.GetBytes(_RelativeOffsetOfLocalHeader), 0, block, i, 8);
i += 8;
// starting disk number
Array.Copy(BitConverter.GetBytes(0), 0, block, i, 4);
}
listOfBlocks.Add(block);
}
#if AESCRYPTO
if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
block = new byte[4 + 7];
int i = 0;
// extra field for WinZip AES
// header id
block[i++] = 0x01;
block[i++] = 0x99;
// data size
block[i++] = 0x07;
block[i++] = 0x00;
// vendor number
block[i++] = 0x01; // AE-1 - means "Verify CRC"
block[i++] = 0x00;
// vendor id "AE"
block[i++] = 0x41;
block[i++] = 0x45;
// key strength
block[i] = 0xFF;
int keystrength = GetKeyStrengthInBits(Encryption);
if (keystrength == 128)
block[i] = 1;
if (keystrength == 256)
block[i] = 3;
i++;
// actual compression method
block[i++] = (byte)(_CompressionMethod & 0x00FF);
block[i++] = (byte)(_CompressionMethod & 0xFF00);
listOfBlocks.Add(block);
}
#endif
if (_ntfsTimesAreSet && _emitNtfsTimes)
{
block = new byte[32 + 4];
// HeaderId 2 bytes 0x000a == NTFS times
// Datasize 2 bytes 32
// reserved 4 bytes ?? don't care
// timetag 2 bytes 0x0001 == NTFS time
// size 2 bytes 24 == 8 bytes each for ctime, mtime, atime
// mtime 8 bytes win32 ticks since win32epoch
// atime 8 bytes win32 ticks since win32epoch
// ctime 8 bytes win32 ticks since win32epoch
int i = 0;
// extra field for NTFS times
// header id
block[i++] = 0x0a;
block[i++] = 0x00;
// data size
block[i++] = 32;
block[i++] = 0;
i += 4; // reserved
// time tag
block[i++] = 0x01;
block[i++] = 0x00;
// data size (again)
block[i++] = 24;
block[i++] = 0;
Int64 z = _Mtime.ToFileTime();
Array.Copy(BitConverter.GetBytes(z), 0, block, i, 8);
i += 8;
z = _Atime.ToFileTime();
Array.Copy(BitConverter.GetBytes(z), 0, block, i, 8);
i += 8;
z = _Ctime.ToFileTime();
Array.Copy(BitConverter.GetBytes(z), 0, block, i, 8);
i += 8;
listOfBlocks.Add(block);
}
if (_ntfsTimesAreSet && _emitUnixTimes)
{
int len = 5 + 4;
if (!forCentralDirectory) len += 8;
block = new byte[len];
// local form:
// --------------
// HeaderId 2 bytes 0x5455 == unix timestamp
// Datasize 2 bytes 13
// flags 1 byte 7 (low three bits all set)
// mtime 4 bytes seconds since unix epoch
// atime 4 bytes seconds since unix epoch
// ctime 4 bytes seconds since unix epoch
//
// central directory form:
//---------------------------------
// HeaderId 2 bytes 0x5455 == unix timestamp
// Datasize 2 bytes 5
// flags 1 byte 7 (low three bits all set)
// mtime 4 bytes seconds since unix epoch
//
int i = 0;
// extra field for "unix" times
// header id
block[i++] = 0x55;
block[i++] = 0x54;
// data size
block[i++] = unchecked((byte)(len - 4));
block[i++] = 0;
// flags
block[i++] = 0x07;
Int32 z = unchecked((int)((_Mtime - _unixEpoch).TotalSeconds));
Array.Copy(BitConverter.GetBytes(z), 0, block, i, 4);
i += 4;
if (!forCentralDirectory)
{
z = unchecked((int)((_Atime - _unixEpoch).TotalSeconds));
Array.Copy(BitConverter.GetBytes(z), 0, block, i, 4);
i += 4;
z = unchecked((int)((_Ctime - _unixEpoch).TotalSeconds));
Array.Copy(BitConverter.GetBytes(z), 0, block, i, 4);
i += 4;
}
listOfBlocks.Add(block);
}
// inject other blocks here...
// concatenate any blocks we've got:
byte[] aggregateBlock = null;
if (listOfBlocks.Count > 0)
{
int totalLength = 0;
int i, current = 0;
for (i = 0; i < listOfBlocks.Count; i++)
totalLength += listOfBlocks[i].Length;
aggregateBlock = new byte[totalLength];
for (i = 0; i < listOfBlocks.Count; i++)
{
System.Array.Copy(listOfBlocks[i], 0, aggregateBlock, current, listOfBlocks[i].Length);
current += listOfBlocks[i].Length;
}
}
return aggregateBlock;
}
// workitem 6513: when writing, use alt encoding only when ibm437 will not do
private System.Text.Encoding GenerateCommentBytes()
{
_CommentBytes = ibm437.GetBytes(_Comment);
// need to use this form of GetString() for .NET CF
string s1 = ibm437.GetString(_CommentBytes, 0, _CommentBytes.Length);
if (s1 == _Comment)
return ibm437;
else
{
_CommentBytes = _provisionalAlternateEncoding.GetBytes(_Comment);
return _provisionalAlternateEncoding;
}
}
// workitem 6513
private byte[] _GetEncodedFileNameBytes()
{
// here, we need to flip the backslashes to forward-slashes,
// also, we need to trim the \\server\share syntax from any UNC path.
// and finally, we need to remove any leading .\
string SlashFixed = FileName.Replace("\\", "/");
string s1 = null;
if ((_TrimVolumeFromFullyQualifiedPaths) && (FileName.Length >= 3)
&& (FileName[1] == ':') && (SlashFixed[2] == '/'))
{
// trim off volume letter, colon, and slash
s1 = SlashFixed.Substring(3);
}
else if ((FileName.Length >= 4)
&& ((SlashFixed[0] == '/') && (SlashFixed[1] == '/')))
{
int n = SlashFixed.IndexOf('/', 2);
if (n == -1)
throw new ArgumentException("The path for that entry appears to be badly formatted");
s1 = SlashFixed.Substring(n + 1);
}
else if ((FileName.Length >= 3)
&& ((SlashFixed[0] == '.') && (SlashFixed[1] == '/')))
{
// trim off dot and slash
s1 = SlashFixed.Substring(2);
}
else
{
s1 = SlashFixed;
}
// workitem 6513: when writing, use the alternative encoding only when ibm437 will not do.
byte[] result = ibm437.GetBytes(s1);
// need to use this form of GetString() for .NET CF
string s2 = ibm437.GetString(result, 0, result.Length);
_CommentBytes = null;
if (s2 == s1)
{
// file can be encoded with ibm437, now try comment
// case 1: no comment. use ibm437
if (_Comment == null || _Comment.Length == 0)
{
_actualEncoding = ibm437;
return result;
}
// there is a comment. Get the encoded form.
System.Text.Encoding commentEncoding = GenerateCommentBytes();
// case 2: if the comment also uses 437, we're good.
if (commentEncoding.CodePage == 437)
{
_actualEncoding = ibm437;
return result;
}
// case 3: comment requires non-437 code page. Use the same
// code page for the filename.
_actualEncoding = commentEncoding;
result = commentEncoding.GetBytes(s1);
return result;
}
else
{
// Cannot encode with ibm437 safely.
// Therefore, use the provisional encoding
result = _provisionalAlternateEncoding.GetBytes(s1);
if (_Comment != null && _Comment.Length != 0)
{
_CommentBytes = _provisionalAlternateEncoding.GetBytes(_Comment);
}
_actualEncoding = _provisionalAlternateEncoding;
return result;
}
}
private bool WantReadAgain()
{
if (_UncompressedSize < 0x10) return false;
if (_CompressionMethod == 0x00) return false;
if (CompressionLevel == Ionic.Zlib.CompressionLevel.None) return false;
if (_CompressedSize < _UncompressedSize) return false;
if (this._Source == ZipEntrySource.Stream && !this._sourceStream.CanSeek) return false;
#if AESCRYPTO
if (_aesCrypto_forWrite != null && (CompressedSize - _aesCrypto_forWrite.SizeOfEncryptionMetadata) <= UncompressedSize + 0x10) return false;
#endif
if (_zipCrypto_forWrite != null && (CompressedSize - 12) <= UncompressedSize) return false;
return true;
}
private void FigureCompressionMethodForWriting(int cycle)
{
// if we've already tried with compression... turn it off this time
if (cycle > 1)
{
_CompressionMethod = 0x0;
return;
}
// compression for directories = 0x00 (No Compression)
if (IsDirectory)
{
_CompressionMethod = 0x0;
return;
}
// if (__FileDataPosition != -1)
// {
// // If at this point, __FileDataPosition is non-zero, that means we've read this
// // entry from an existing zip archive.
// //
// // In this case, we just keep the existing file data and metadata (including
// // CompressionMethod, CRC, compressed size, uncompressed size, etc).
// //
// // All those member variables have been set during read!
// //
// return;
// }
if (this._Source == ZipEntrySource.ZipFile)
{
return;
}
// If __FileDataPosition is zero, then that means we will get the data
// from a file or stream.
// It is never possible to compress a zero-length file, so we check for
// this condition.
if (this._Source == ZipEntrySource.Stream)
{
// workitem 7742
if (_sourceStream != null && _sourceStream.CanSeek)
{
// Length prop will throw if CanSeek is false
long fileLength = _sourceStream.Length;
if (fileLength == 0)
{
_CompressionMethod = 0x00;
return;
}
}
}
else if ((this._Source == ZipEntrySource.FileSystem) && (SharedUtilities.GetFileLength(LocalFileName) == 0L))
{
_CompressionMethod = 0x00;
return;
}
// Ok, we're getting the data to be compressed from a
// non-zero-length file or stream, or a file or stream of
// unknown length, and we presume that it is non-zero. In
// that case we check the callback to see if the app wants
// to tell us whether to compress or not.
if (SetCompression != null)
CompressionLevel = SetCompression(LocalFileName, _FileNameInArchive);
_CompressionMethod = (short)((CompressionLevel == Ionic.Zlib.CompressionLevel.None)
? 0x00
: 0x08);
return;
}
// write the header info for an entry
internal void WriteHeader(Stream s, int cycle)
{
// Must remember the offset, within the output stream, of this particular
// entry header.
//
// This is for 2 reasons:
//
// 1. so we can determine the RelativeOffsetOfLocalHeader (ROLH) for use in the
// central directory.
// 2. so we can seek backward in case there is an error opening or reading
// the file, and the application decides to skip the file. In this case,
// we need to seek backward in the output stream to allow the next entry
// to be added to the zipfile output stream.
//
// Normally you would just store the offset before writing to the output
// stream and be done with it. But the possibility to use split archives
// makes this approach ineffective. In split archives, each file or segment
// is bound to a max size limit, and each local file header must not span a
// segment boundary; it must be written contiguously. If it will fit in the
// current segment, then the ROLH is just the current Position in the output
// stream. If it won't fit, then we need a new file (segment) and the ROLH
// is zero.
//
// But we only can know if it is possible to write a header contiguously
// after we know the size of the local header, a size that varies with
// things like filename length, comments, and extra fields. We have to
// compute the header fully before knowing whether it will fit.
//
// That takes care of item #1 above. Now, regarding #2. If an error occurs
// while computing the local header, we want to just seek backward. The
// exception handling logic (in the caller of WriteHeader) uses ROLH to
// scroll back.
//
// All this means we have to preserve the starting offset before computing
// the header, and also we have to compute the offset later, to handle the
// case of split archives.
var counter = s as CountingStream;
// workitem 8098: ok (output)
// This may change later, for split archives
// Don't set _RelativeOffsetOfLocalHeader. Instead, set a temp variable.
// This allows for re-streaming, where a zip entry might be read from a
// zip archive (and maybe decrypted, and maybe decompressed) and then
// written to another zip archive, with different settings for
// compression method, compression level, or encryption algorithm.
_future_ROLH = (counter != null)
? counter.ComputedPosition
: s.Position;
int j = 0;
int i = 0;
byte[] bytes = new byte[512]; // large enough for looooong filenames (MAX_PATH == 260)
// signature
bytes[i++] = (byte)(ZipConstants.ZipEntrySignature & 0x000000FF);
bytes[i++] = (byte)((ZipConstants.ZipEntrySignature & 0x0000FF00) >> 8);
bytes[i++] = (byte)((ZipConstants.ZipEntrySignature & 0x00FF0000) >> 16);
bytes[i++] = (byte)((ZipConstants.ZipEntrySignature & 0xFF000000) >> 24);
// Design notes for ZIP64:
// The specification says that the header must include the Compressed and
// Uncompressed sizes, as well as the CRC32 value. When creating a zip via
// streamed processing, these quantities are not known until after the compression
// is done. Thus, a typical way to do it is to insert zeroes for these quantities,
// then do the compression, then seek back to insert the appropriate values, then
// seek forward to the end of the file data.
// There is also the option of using bit 3 in the GP bitfield - to specify that
// there is a data descriptor after the file data containing these three
// quantities.
// This works when the size of the quantities is known, either 32-bits or 64 bits as
// with the ZIP64 extensions.
// With Zip64, the 4-byte fields are set to 0xffffffff, and there is a
// corresponding data block in the "extra field" that contains the actual
// Compressed, uncompressed sizes. (As well as an additional field, the "Relative
// Offset of Local Header")
// The problem is when the app desires to use ZIP64 extensions optionally, only
// when necessary. Suppose the library assumes no zip64 extensions when writing
// the header, then after compression finds that the size of the data requires
// zip64. At this point, the header, already written to the file, won't have the
// necessary data block in the "extra field". The size of the entry header is
// fixed, so it is not possible to just "add on" the zip64 data block after
// compressing the file. On the other hand, always using zip64 will break
// interoperability with many other systems and apps.
// The approach we take is to insert a 32-byte dummy data block in the extra field,
// whenever zip64 is to be used "as necessary". This data block will get the actual
// zip64 HeaderId and zip64 metadata if necessary. If not necessary, the data
// block will get a meaningless HeaderId (0x1111), and will be filled with zeroes.
// When zip64 is actually in use, we also need to set the VersionNeededToExtract
// field to 45.
// There is one additional wrinkle: using zip64 as necessary conflicts with output
// to non-seekable devices. The header is emitted and must indicate whether zip64
// is in use, before we know if zip64 is necessary. Because there is no seeking,
// the header can never be changed. Therefore, on non-seekable devices,
// Zip64Option.AsNecessary is the same as Zip64Option.Always.
// version needed- see AppNote.txt.
// need v5.1 for PKZIP strong encryption, or v2.0 for no encryption or for PK
// encryption, 4.5 for zip64. We may reset this later, as necessary or zip64.
_presumeZip64 = (_container.Zip64 == Zip64Option.Always || (_container.Zip64 == Zip64Option.AsNecessary && !s.CanSeek));
Int16 VersionNeededToExtract = (Int16)(_presumeZip64 ? 45 : 20);
// (i==4)
bytes[i++] = (byte)(VersionNeededToExtract & 0x00FF);
bytes[i++] = (byte)((VersionNeededToExtract & 0xFF00) >> 8);
// get byte array including any encoding
// workitem 6513
byte[] FileNameBytes = _GetEncodedFileNameBytes();
Int16 filenameLength = (Int16)FileNameBytes.Length;
// general purpose bitfield
// In the current implementation, this library uses only these bits
// in the GP bitfield:
// bit 0 = if set, indicates the entry is encrypted
// bit 3 = if set, indicates the CRC, C and UC sizes follow the file data.
// bit 6 = strong encryption - for pkware's meaning of strong encryption
// bit 11 = UTF-8 encoding is used in the comment and filename
// Here we set or unset the encryption bit.
// _BitField may already be set, as with a ZipEntry added into ZipOutputStream, which
// has bit 3 always set. We only want to set one bit
if (_Encryption == EncryptionAlgorithm.None)
_BitField &= ~1; // encryption bit OFF
else
_BitField |= 1; // encryption bit ON
// workitem 7941: WinZip does not the "strong encryption" bit when using AES.
// This "Strong Encryption" is a PKWare Strong encryption thing.
// _BitField |= 0x0020;
// set the UTF8 bit if necessary
if (ActualEncoding.CodePage == System.Text.Encoding.UTF8.CodePage) _BitField |= 0x0800;
// The PKZIP spec says that if bit 3 is set (0x0008) in the General Purpose BitField,
// then the CRC, Compressed size, and uncompressed size are written directly after the
// file data.
//
// These 3 quantities are normally present in the regular zip entry header. But, they
// are not knowable until after the compression is done. So, in the normal case, we
// - write the header, using zeros for these quantities
// - compress the data, and incidentally compute these quantities.
// - seek back and write the correct values them into the header.
//
// This is nice because, while it is more complicated to write the zip file, it is
// simpler and less error prone to read the zip file, and as a result more
// applications can read zip files produced this way, with those 3 quantities in the
// header.
//
// But if seeking in the output stream is not possible, then we need to set the
// appropriate bitfield and emit these quantities after the compressed file data in
// the output.
//
// workitem 7216 - having trouble formatting a zip64 file that is readable by WinZip.
// not sure why! What I found is that setting bit 3 and following all the implications,
// the zip64 file is readable by WinZip 12. and Perl's IO::Compress::Zip .
// Perl takes an interesting approach - it always sets bit 3 if ZIP64 in use.
// DotNetZip now does the same; this gives better compatibility with WinZip 12.
if (IsDirectory || cycle == 99)
{
// (cycle == 99) indicates a zero-length entry written by ZipOutputStream
_BitField &= ~0x0008; // unset bit 3 - no "data descriptor" - ever
_BitField &= ~0x0001; // unset bit 1 - no encryption - ever
Encryption = EncryptionAlgorithm.None;
Password = null;
}
else if (!s.CanSeek)
_BitField |= 0x0008;
#if DONT_GO_THERE
else if (this.Encryption == EncryptionAlgorithm.PkzipWeak &&
this._Source != ZipEntrySource.ZipFile)
{
// Set bit 3 to avoid the double-read perf issue.
//
// When PKZIP encryption is used, byte 11 of the encryption header is
// used as a consistency check. It is normally set to the MSByte of the
// CRC. But this means the cRC must be known ebfore compression and
// encryption, which means the entire stream has to be read twice. To
// avoid that, the high-byte of the time blob (when in DOS format) can
// be used for the consistency check (byte 11 in the encryption header).
// But this means the entry must have bit 3 set.
//
// Previously I used a more complex arrangement - using the methods like
// FigureCrc32(), PrepOutputStream() and others, in order to manage the
// seek-back in the source stream. Why? Because bit 3 is not always
// friendly with third-party zip tools, like those on the Mac.
//
// This is why this code is still ifdef'd out.
//
// Might consider making this yet another programmable option -
// AlwaysUseBit3ForPkzip. But that's for another day.
//
_BitField |= 0x0008;
}
#endif
// (i==6)
bytes[i++] = (byte)(_BitField & 0x00FF);
bytes[i++] = (byte)((_BitField & 0xFF00) >> 8);
// Here, we want to set values for Compressed Size, Uncompressed Size, and CRC. If
// we have __FileDataPosition as not -1 (zero is a valid FDP), then that means we
// are reading this zip entry from a zip file, and we have good values for those
// quantities.
//
// If _FileDataPosition is -1, then we are constructing this Entry from nothing. We
// zero those quantities now, and we will compute actual values for the three
// quantities later, when we do the compression, and then seek back to write them
// into the appropriate place in the header.
if (this.__FileDataPosition == -1)
{
//_UncompressedSize = 0; // do not unset - may need this value for restream
// _Crc32 = 0; // ditto
_CompressedSize = 0;
_crcCalculated = false;
}
// set compression method here
FigureCompressionMethodForWriting(cycle);
// (i==8) compression method
bytes[i++] = (byte)(_CompressionMethod & 0x00FF);
bytes[i++] = (byte)((_CompressionMethod & 0xFF00) >> 8);
if (cycle == 99)
{
// (cycle == 99) indicates a zero-length entry written by ZipOutputStream
SetZip64Flags();
}
#if AESCRYPTO
else if (Encryption == EncryptionAlgorithm.WinZipAes128 || Encryption == EncryptionAlgorithm.WinZipAes256)
{
i -= 2;
bytes[i++] = 0x63;
bytes[i++] = 0;
}
#endif
// LastMod
_TimeBlob = Ionic.Zip.SharedUtilities.DateTimeToPacked(LastModified);
// (i==10) time blob
bytes[i++] = (byte)(_TimeBlob & 0x000000FF);
bytes[i++] = (byte)((_TimeBlob & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_TimeBlob & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_TimeBlob & 0xFF000000) >> 24);
// (i==14) CRC - if source==filesystem, this is zero now, actual value will be calculated later.
// if source==archive, this is a bonafide value.
bytes[i++] = (byte)(_Crc32 & 0x000000FF);
bytes[i++] = (byte)((_Crc32 & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_Crc32 & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_Crc32 & 0xFF000000) >> 24);
if (_presumeZip64)
{
// (i==18) CompressedSize (Int32) and UncompressedSize - all 0xFF for now
for (j = 0; j < 8; j++)
bytes[i++] = 0xFF;
}
else
{
// (i==18) CompressedSize (Int32) - this value may or may not be bonafide.
// if source == filesystem, then it is zero, and we'll learn it after we compress.
// if source == archive, then it is bonafide data.
bytes[i++] = (byte)(_CompressedSize & 0x000000FF);
bytes[i++] = (byte)((_CompressedSize & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_CompressedSize & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_CompressedSize & 0xFF000000) >> 24);
// (i==22) UncompressedSize (Int32) - this value may or may not be bonafide.
bytes[i++] = (byte)(_UncompressedSize & 0x000000FF);
bytes[i++] = (byte)((_UncompressedSize & 0x0000FF00) >> 8);
bytes[i++] = (byte)((_UncompressedSize & 0x00FF0000) >> 16);
bytes[i++] = (byte)((_UncompressedSize & 0xFF000000) >> 24);
}
// (i==26) filename length (Int16)
bytes[i++] = (byte)(filenameLength & 0x00FF);
bytes[i++] = (byte)((filenameLength & 0xFF00) >> 8);
_Extra = ConstructExtraField(false);
// (i==28) extra field length (short)
Int16 ExtraFieldLength = (Int16)((_Extra == null) ? 0 : _Extra.Length);
bytes[i++] = (byte)(ExtraFieldLength & 0x00FF);
bytes[i++] = (byte)((ExtraFieldLength & 0xFF00) >> 8);
// The filename written to the archive.
// The buffer is already encoded; we just copy across the bytes.
for (j = 0; (j < FileNameBytes.Length) && (i + j < bytes.Length); j++)
bytes[i + j] = FileNameBytes[j];
i += j;
// "Extra field"
if (_Extra != null)
{
for (j = 0; j < _Extra.Length; j++)
bytes[i + j] = _Extra[j];
i += j;
}
_LengthOfHeader = i;
// handle split archives
var zss = s as ZipSegmentedStream;
if (zss != null)
{
zss.ContiguousWrite = true;
UInt32 requiredSegment = zss.ComputeSegment(i);
if (requiredSegment != zss.CurrentSegment)
_future_ROLH = 0; // rollover!
else
_future_ROLH = zss.Position;
_diskNumber = requiredSegment;
}
// validate the ZIP64 usage
if (_container.Zip64 == Zip64Option.Never && (uint)_RelativeOffsetOfLocalHeader >= 0xFFFFFFFF)
throw new ZipException("Offset within the zip archive exceeds 0xFFFFFFFF. Consider setting the UseZip64WhenSaving property on the ZipFile instance.");
// finally, write the header to the stream
s.Write(bytes, 0, i);
// now that the header is written, we can turn off the contiguous write restriction.
if (zss != null)
zss.ContiguousWrite = false;
// preserve this header data, we'll use it again later.
// ..when seeking backward, to write again, after we have the Crc, compressed
// and uncompressed sizes.
// ..and when writing the central directory structure.
_EntryHeader = new byte[i];
for (j = 0; j < i; j++)
_EntryHeader[j] = bytes[j];
}
private Int32 FigureCrc32()
{
if (_crcCalculated == false)
{
Stream input = null;
// get the original stream:
if (this._Source == ZipEntrySource.WriteDelegate)
{
var output = new Ionic.Zlib.CrcCalculatorStream(Stream.Null);
// allow the application to write the data
this._WriteDelegate(this.FileName, output);
_Crc32 = output.Crc;
}
else if (this._Source == ZipEntrySource.ZipFile)
{
// nothing to do - the CRC is already set
}
else
{
if (this._Source == ZipEntrySource.Stream)
{
PrepSourceStream();
input = _sourceStream;
}
else if (this._Source == ZipEntrySource.JitStream)
{
// allow the application to open the stream
if (this._sourceStream == null) _sourceStream = this._OpenDelegate(this.FileName);
PrepSourceStream();
input = this._sourceStream;
}
else if (this._Source == ZipEntrySource.ZipOutputStream)
{
//throw new InvalidOperationException("you cannot use PKZIP encryption with a ZipOutputStream.");
}
else
{
//input = File.OpenRead(LocalFileName);
input = File.Open(LocalFileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
}
var crc32 = new Ionic.Zlib.CRC32();
_Crc32 = crc32.GetCrc32(input);
if (_sourceStream == null)
{
input.Close();
#if !NETCF
input.Dispose();
#endif
}
}
_crcCalculated = true;
}
return _Crc32;
}
/// <summary>
/// Stores the position of the entry source stream, or, if the position is
/// already stored, seeks to that position.
/// </summary>
///
/// <remarks>
/// <para>
/// This method is called in prep for reading the source stream. If PKZIP
/// encryption is used, then we need to calc the CRC32 before doing the
/// encryption, because the CRC is used in the 12th byte of the PKZIP
/// encryption header. So, we need to be able to seek backward in the source
/// when saving the ZipEntry. This method is called from the place that
/// calculates the CRC, and also from the method that does the encryption of
/// the file data.
/// </para>
///
/// <para>
/// The first time through, this method sets the _sourceStreamOriginalPosition
/// field. Subsequent calls to this method seek to that position.
/// </para>
/// </remarks>
private void PrepSourceStream()
{
if (_sourceStream == null)
throw new ZipException(String.Format("The input stream is null for entry '{0}'.", FileName));
if (this._sourceStreamOriginalPosition != null)
{
// this will happen the 2nd cycle through, if the stream is seekable
this._sourceStream.Position = this._sourceStreamOriginalPosition.Value;
}
else if (this._sourceStream.CanSeek)
{
// this will happen the first cycle through, if seekable
this._sourceStreamOriginalPosition = new Nullable<Int64>(this._sourceStream.Position);
}
else if (this.Encryption == EncryptionAlgorithm.PkzipWeak)
{
// In general, using PKZIP encryption on a a zip entry whose input
// comes from a non-seekable stream, is tricky. Here's why:
//
// Byte 11 of the PKZIP encryption header is used for password
// validation and consistency checknig.
//
// Normally, the highest byte of the CRC is used as the 11th (last) byte
// in the PKZIP encryption header. This means the CRC must be known
// before encryption is performed. Normally that means we read the full
// data stream, compute the CRC, then seek back and read it again for
// the compression+encryption phase. Obviously this is bad for
// performance with a large input file.
//
// There's a twist in the ZIP spec (actually documented only in infozip
// code, not in the spec itself) that allows the high-order byte of the
// last modified time for the entry, when the lastmod time is in packed
// (DOS) format, to be used for Byte 11 in the encryption header. In
// this case, the bit 3 "data descriptor" must be used.
//
// An intelligent implementation would therefore force the use of the
// bit 3 data descriptor when PKZIP encryption is in use, regardless.
// This avoids the double-read of the stream to be encrypted. So far,
// DotNetZip doesn't do that; it just punts when the input stream is
// non-seekable, and the output does not use Bit 3.
//
// The other option is to use the CRC when it is already available, eg,
// when the source for the data is a ZipEntry (when the zip file is
// being updated). In this case we already know the CRC and can just use
// what we know.
if (this._Source != ZipEntrySource.ZipFile && ((this._BitField & 0x0008) != 0x0008))
throw new ZipException("It is not possible to use PKZIP encryption on a non-seekable input stream");
}
}
/// <summary>
/// Copy metadata that may have been changed by the app. We do this when
/// resetting the zipFile instance. If the app calls Save() on a ZipFile, then
/// tries to party on that file some more, we may need to Reset() it , which
/// means re-reading the entries and then copying the metadata. I think.
/// </summary>
internal void CopyMetaData(ZipEntry source)
{
this.__FileDataPosition = source.__FileDataPosition;
this.CompressionMethod = source.CompressionMethod;
this._CompressionMethod_FromZipFile = source._CompressionMethod_FromZipFile;
this._CompressedFileDataSize = source._CompressedFileDataSize;
this._UncompressedSize = source._UncompressedSize;
this._BitField = source._BitField;
this._Source = source._Source;
this._LastModified = source._LastModified;
this._Mtime = source._Mtime;
this._Atime = source._Atime;
this._Ctime = source._Ctime;
this._ntfsTimesAreSet = source._ntfsTimesAreSet;
this._emitUnixTimes = source._emitUnixTimes;
this._emitNtfsTimes = source._emitNtfsTimes;
}
private void OnWriteBlock(Int64 bytesXferred, Int64 totalBytesToXfer)
{
if (_container.ZipFile != null)
_ioOperationCanceled = _container.ZipFile.OnSaveBlock(this, bytesXferred, totalBytesToXfer);
}
private void _WriteEntryData(Stream s)
{
// Read in the data from the input stream (often a file in the filesystem),
// and write it to the output stream, calculating a CRC on it as we go.
// We will also deflate and encrypt as necessary.
Stream input = null;
long fdp = -1L;
try
{
// Want to record the position in the zip file of the zip entry data (as opposed to the metadata).
// s.Position may fail on some write-only streams, eg stdout or
// System.Web.HttpResponseStream.
// We swallow that exception, because we don't care, in that case.
// But, don't set __FileDataPosition directly. It may be needed to READ
// the zip entry from the zip file, if this is a "re-stream" situation. In other words
// if the zip entry has changed compression level, or compression method, or
// (maybe?) encryption algorithm.
// In that case if the original entry is encrypted, we need __FileDataPosition to be
// the value for the input zip file. This s.Position is for the output zipfile.
// So we copy fdp to __FileDataPosition after this entry has been (maybe) restreamed.
fdp = s.Position;
}
catch { }
try
{
// Use fileLength for progress updates, and to decide whether
// we can skip encryption and deflation altogether (in case of length==zero)
long fileLength = SetInputAndFigureFileLength(ref input);
CountingStream entryCounter; // counts bytes written for this entry
Stream encryptor;
Stream deflater;
Ionic.Zlib.CrcCalculatorStream output;
PrepOutputStream(s, fileLength, out entryCounter, out encryptor, out deflater, out output);
// as we emit the file, the flow is:
// calc-crc -> deflate -> encrypt -> count -> actually write
if (this._Source == ZipEntrySource.WriteDelegate)
{
// allow the application to write the data
this._WriteDelegate(this.FileName, output);
}
else
{
// synchronously copy the input stream to the output stream-chain
byte[] buffer = new byte[BufferSize];
int n;
while ((n = SharedUtilities.ReadWithRetry(input, buffer, 0, buffer.Length, FileName)) != 0)
{
output.Write(buffer, 0, n);
OnWriteBlock(output.TotalBytesSlurped, fileLength);
if (_ioOperationCanceled)
break;
}
}
FinishOutputStream(s, entryCounter, encryptor, deflater, output);
}
finally
{
if (this._Source == ZipEntrySource.JitStream)
{
// allow the application to open the stream
if (this._CloseDelegate != null)
this._CloseDelegate(this.FileName, input);
}
else if ((input as FileStream) != null)
{
input.Close();
#if !NETCF
input.Dispose();
#endif
}
}
if (_ioOperationCanceled)
return;
// set FDP now, to allow for re-streaming
this.__FileDataPosition = fdp;
PostProcessOutput(s);
}
/// <summary>
/// Set the input stream and get its length, if possible. The
/// length is used for progress updates, AND, to allow an
/// optimization in case of a stream/file of zero length. In
/// that case we skip the Encrypt and DeflateStream.
/// </summary>
private long SetInputAndFigureFileLength(ref Stream input)
{
long fileLength = -1L;
// get the original stream:
if (this._Source == ZipEntrySource.Stream)
{
PrepSourceStream();
input = this._sourceStream;
// Try to get the length, no big deal if not available.
try { fileLength = this._sourceStream.Length; }
catch (NotSupportedException) { }
}
else if (this._Source == ZipEntrySource.ZipFile)
{
// we are "re-streaming" the zip entry.
string pwd = (_Encryption_FromZipFile == EncryptionAlgorithm.None) ? null : (this._Password ?? this._container.Password);
this._sourceStream = InternalOpenReader(pwd);
PrepSourceStream();
input = this._sourceStream;
fileLength = this._sourceStream.Length;
}
else if (this._Source == ZipEntrySource.JitStream)
{
// allow the application to open the stream
if (this._sourceStream == null) _sourceStream = this._OpenDelegate(this.FileName);
PrepSourceStream();
input = this._sourceStream;
try { fileLength = this._sourceStream.Length; }
catch (NotSupportedException) { }
}
else if (this._Source == ZipEntrySource.FileSystem)
{
// workitem 7145
FileShare fs = FileShare.ReadWrite;
#if !NETCF
// FileShare.Delete is not defined for the Compact Framework
fs |= FileShare.Delete;
#endif
// workitem 8423
input = File.Open(LocalFileName, FileMode.Open, FileAccess.Read, fs);
fileLength = input.Length;
}
return fileLength;
}
internal void FinishOutputStream(Stream s,
CountingStream entryCounter,
Stream encryptor,
Stream deflater,
Ionic.Zlib.CrcCalculatorStream output)
{
if (output == null) return;
output.Close();
// by calling Close() on the deflate stream, we write the footer bytes, as necessary.
if ((deflater as Ionic.Zlib.DeflateStream) != null)
deflater.Close();
#if !NETCF
else if ((deflater as Ionic.Zlib.ParallelDeflateOutputStream) != null)
deflater.Close();
#endif
encryptor.Flush();
encryptor.Close();
_LengthOfTrailer = 0;
_UncompressedSize = output.TotalBytesSlurped;
#if AESCRYPTO
WinZipAesCipherStream wzacs = encryptor as WinZipAesCipherStream;
if (wzacs != null && _UncompressedSize > 0)
{
s.Write(wzacs.FinalAuthentication, 0, 10);
_LengthOfTrailer += 10;
}
#endif
_CompressedFileDataSize = entryCounter.BytesWritten;
_CompressedSize = _CompressedFileDataSize; // may be adjusted
_Crc32 = output.Crc;
// Set _RelativeOffsetOfLocalHeader now, to allow for re-streaming
StoreRelativeOffset();
}
internal void PostProcessOutput(Stream s)
{
// workitem 8931 - for WriteDelegate.
// The WriteDelegate changes things because there can be a zero-byte stream
// written. In all other cases DotNetZip knows the length of the stream
// before compressing and encrypting. In this case we have to circle back,
// and omit all the crypto stuff - the GP bitfield, and the crypto header.
if (_UncompressedSize == 0 && _CompressedSize == 0)
{
if (this._Source == ZipEntrySource.ZipOutputStream) return; // nothing to do...
if (_Password != null)
{
int headerBytesToRetract = 0;
if (Encryption == EncryptionAlgorithm.PkzipWeak)
headerBytesToRetract = 12;
#if AESCRYPTO
else if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
headerBytesToRetract = _aesCrypto_forWrite._Salt.Length + _aesCrypto_forWrite.GeneratedPV.Length;
}
#endif
if (this._Source == ZipEntrySource.ZipOutputStream && !s.CanSeek)
throw new ZipException("Zero bytes written, encryption in use, and non-seekable output.");
if (Encryption != EncryptionAlgorithm.None)
{
// seek back in the stream to un-output the security metadata
s.Seek(-1 * headerBytesToRetract, SeekOrigin.Current);
s.SetLength(s.Position);
// workitem 10178
Ionic.Zip.SharedUtilities.Workaround_Ladybug318918(s);
// subtract the size of the security header from the _LengthOfHeader
_LengthOfHeader -= headerBytesToRetract;
}
_Password = null;
// turn off the encryption bit
_BitField &= ~(0x0001);
int j = 6;
_EntryHeader[j++] = (byte)(_BitField & 0x00FF);
_EntryHeader[j++] = (byte)((_BitField & 0xFF00) >> 8);
}
CompressionMethod = 0;
Encryption = EncryptionAlgorithm.None;
}
else if (_zipCrypto_forWrite != null
#if AESCRYPTO
|| _aesCrypto_forWrite != null
#endif
)
{
if (Encryption == EncryptionAlgorithm.PkzipWeak)
{
_CompressedSize += 12; // 12 extra bytes for the encryption header
}
#if AESCRYPTO
else if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
// adjust the compressed size to include the variable (salt+pv)
// security header and 10-byte trailer. According to the winzip AES
// spec, that metadata is included in the "Compressed Size" figure
// when encoding the zip archive.
_CompressedSize += _aesCrypto_forWrite.SizeOfEncryptionMetadata;
}
#endif
}
int i = 8;
_EntryHeader[i++] = (byte)(_CompressionMethod & 0x00FF);
_EntryHeader[i++] = (byte)((_CompressionMethod & 0xFF00) >> 8);
i = 14;
// CRC - the correct value now
_EntryHeader[i++] = (byte)(_Crc32 & 0x000000FF);
_EntryHeader[i++] = (byte)((_Crc32 & 0x0000FF00) >> 8);
_EntryHeader[i++] = (byte)((_Crc32 & 0x00FF0000) >> 16);
_EntryHeader[i++] = (byte)((_Crc32 & 0xFF000000) >> 24);
SetZip64Flags();
// (i==26) filename length (Int16)
Int16 filenameLength = (short)(_EntryHeader[26] + _EntryHeader[27] * 256);
Int16 extraFieldLength = (short)(_EntryHeader[28] + _EntryHeader[29] * 256);
if (_OutputUsesZip64.Value)
{
// VersionNeededToExtract - set to 45 to indicate zip64
_EntryHeader[4] = (byte)(45 & 0x00FF);
_EntryHeader[5] = 0x00;
// workitem 7924 - don't need bit 3
// // workitem 7917
// // set bit 3 for ZIP64 compatibility with WinZip12
// _BitField |= 0x0008;
// _EntryHeader[6] = (byte)(_BitField & 0x00FF);
// CompressedSize and UncompressedSize - 0xFF
for (int j = 0; j < 8; j++)
_EntryHeader[i++] = 0xff;
// At this point we need to find the "Extra field" that
// follows the filename. We had already emitted it, but
// the data (uncomp, comp, Relative Offset of Local
// Header) was not available at the time we did so.
// Here, we emit it again, with final values.
i = 30 + filenameLength;
_EntryHeader[i++] = 0x01; // zip64
_EntryHeader[i++] = 0x00;
i += 2; // skip over data size, which is 16+4
Array.Copy(BitConverter.GetBytes(_UncompressedSize), 0, _EntryHeader, i, 8);
i += 8;
Array.Copy(BitConverter.GetBytes(_CompressedSize), 0, _EntryHeader, i, 8);
}
else
{
// VersionNeededToExtract - reset to 20 since no zip64
_EntryHeader[4] = (byte)(20 & 0x00FF);
_EntryHeader[5] = 0x00;
// CompressedSize - the correct value now
i = 18;
_EntryHeader[i++] = (byte)(_CompressedSize & 0x000000FF);
_EntryHeader[i++] = (byte)((_CompressedSize & 0x0000FF00) >> 8);
_EntryHeader[i++] = (byte)((_CompressedSize & 0x00FF0000) >> 16);
_EntryHeader[i++] = (byte)((_CompressedSize & 0xFF000000) >> 24);
// UncompressedSize - the correct value now
_EntryHeader[i++] = (byte)(_UncompressedSize & 0x000000FF);
_EntryHeader[i++] = (byte)((_UncompressedSize & 0x0000FF00) >> 8);
_EntryHeader[i++] = (byte)((_UncompressedSize & 0x00FF0000) >> 16);
_EntryHeader[i++] = (byte)((_UncompressedSize & 0xFF000000) >> 24);
// The HeaderId in the extra field header, is already dummied out.
if (extraFieldLength != 0)
{
i = 30 + filenameLength;
// For zip archives written by this library, if the zip64 header exists,
// it is the first header. Because of the logic used when first writing the
// _EntryHeader bytes, the HeaderId is not guaranteed to be any
// particular value. So we determine if the first header is a putative zip64
// header by examining the datasize.
//UInt16 HeaderId = (UInt16)(_EntryHeader[i] + _EntryHeader[i + 1] * 256);
Int16 DataSize = (short)(_EntryHeader[i + 2] + _EntryHeader[i + 3] * 256);
if (DataSize == 16)
{
// reset to Header Id to dummy value, effectively dummy-ing out the zip64 metadata
_EntryHeader[i++] = 0x99;
_EntryHeader[i++] = 0x99;
}
}
}
#if AESCRYPTO
if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
// Must set compressionmethod to 0x0063 (decimal 99)
// and then set the compression method bytes inside the extra field to the actual
// compression method value.
i = 8;
_EntryHeader[i++] = 0x63;
_EntryHeader[i++] = 0;
i = 30 + filenameLength;
do
{
UInt16 HeaderId = (UInt16)(_EntryHeader[i] + _EntryHeader[i + 1] * 256);
Int16 DataSize = (short)(_EntryHeader[i + 2] + _EntryHeader[i + 3] * 256);
if (HeaderId != 0x9901)
{
// skip this header
i += DataSize + 4;
}
else
{
i += 9;
// actual compression method
_EntryHeader[i++] = (byte)(_CompressionMethod & 0x00FF);
_EntryHeader[i++] = (byte)(_CompressionMethod & 0xFF00);
}
} while (i < (extraFieldLength - 30 - filenameLength));
}
#endif
// finally, write the data.
// workitem 7216 - sometimes we don't seek even if we CAN. ASP.NET
// Response.OutputStream, or stdout are non-seekable. But we may also want
// to NOT seek in other cases, eg zip64. For all cases, we just check bit 3
// to see if we want to seek. There's one exception - if using a
// ZipOutputStream, and PKZip encryption is in use, then we set bit 3 even
// if the out is seekable. This is so the check on the last byte of the
// PKZip Encryption Header can be done on the current time, as opposed to
// the CRC, to prevent streaming the file twice. So, test for
// ZipOutputStream and seekable, and if so, seek back, even if bit 3 is set.
if ((_BitField & 0x0008) != 0x0008 ||
(this._Source == ZipEntrySource.ZipOutputStream && s.CanSeek))
{
// seek back and rewrite the entry header
var zss = s as ZipSegmentedStream;
if (zss != null && _diskNumber != zss.CurrentSegment)
{
// in this case the entry header is in a different file
using (Stream firstSeg = ZipSegmentedStream.ForUpdate(this._container.ZipFile.Name, _diskNumber))
{
firstSeg.Seek(this._RelativeOffsetOfLocalHeader, SeekOrigin.Begin);
// write the updated header to the output stream
firstSeg.Write(_EntryHeader, 0, _EntryHeader.Length);
}
}
else
{
// seek in the raw output stream, to the beginning of the header for
// this entry.
// workitem 8098: ok (output)
s.Seek(this._RelativeOffsetOfLocalHeader, SeekOrigin.Begin);
// write the updated header to the output stream
s.Write(_EntryHeader, 0, _EntryHeader.Length);
// adjust the count on the CountingStream as necessary
var s1 = s as CountingStream;
if (s1 != null) s1.Adjust(_EntryHeader.Length);
// seek in the raw output stream, to the end of the file data for this entry
s.Seek(_CompressedSize, SeekOrigin.Current);
}
}
// emit the descriptor - only if not a directory.
if (((_BitField & 0x0008) == 0x0008) && !IsDirectory)
{
byte[] Descriptor = new byte[16 + (_OutputUsesZip64.Value ? 8 : 0)];
i = 0;
// signature
Array.Copy(BitConverter.GetBytes(ZipConstants.ZipEntryDataDescriptorSignature), 0, Descriptor, i, 4);
i += 4;
// CRC - the correct value now
Array.Copy(BitConverter.GetBytes(_Crc32), 0, Descriptor, i, 4);
i += 4;
// workitem 7917
if (_OutputUsesZip64.Value)
{
// CompressedSize - the correct value now
Array.Copy(BitConverter.GetBytes(_CompressedSize), 0, Descriptor, i, 8);
i += 8;
// UncompressedSize - the correct value now
Array.Copy(BitConverter.GetBytes(_UncompressedSize), 0, Descriptor, i, 8);
i += 8;
}
else
{
// CompressedSize - (lower 32 bits) the correct value now
Descriptor[i++] = (byte)(_CompressedSize & 0x000000FF);
Descriptor[i++] = (byte)((_CompressedSize & 0x0000FF00) >> 8);
Descriptor[i++] = (byte)((_CompressedSize & 0x00FF0000) >> 16);
Descriptor[i++] = (byte)((_CompressedSize & 0xFF000000) >> 24);
// UncompressedSize - (lower 32 bits) the correct value now
Descriptor[i++] = (byte)(_UncompressedSize & 0x000000FF);
Descriptor[i++] = (byte)((_UncompressedSize & 0x0000FF00) >> 8);
Descriptor[i++] = (byte)((_UncompressedSize & 0x00FF0000) >> 16);
Descriptor[i++] = (byte)((_UncompressedSize & 0xFF000000) >> 24);
}
// finally, write the trailing descriptor to the output stream
s.Write(Descriptor, 0, Descriptor.Length);
_LengthOfTrailer += Descriptor.Length;
}
}
private void SetZip64Flags()
{
// zip64 housekeeping
_entryRequiresZip64 = new Nullable<bool>
(_CompressedSize >= 0xFFFFFFFF || _UncompressedSize >= 0xFFFFFFFF || _RelativeOffsetOfLocalHeader >= 0xFFFFFFFF);
// validate the ZIP64 usage
if (_container.Zip64 == Zip64Option.Never && _entryRequiresZip64.Value)
throw new ZipException("Compressed or Uncompressed size, or offset exceeds the maximum value. Consider setting the UseZip64WhenSaving property on the ZipFile instance.");
_OutputUsesZip64 = new Nullable<bool>(_container.Zip64 == Zip64Option.Always || _entryRequiresZip64.Value);
}
internal void PrepOutputStream(Stream s,
long streamLength,
out CountingStream outputCounter,
out Stream encryptor,
out Stream deflater,
out Ionic.Zlib.CrcCalculatorStream output)
{
TraceWriteLine("PrepOutputStream: e({0}) comp({1}) crypto({2}) zf({3})", FileName, CompressionLevel, Encryption, (_container).Name);
// Wrap a counting stream around the raw output stream:
// This is the last thing that happens before the bits go to the
// application-provided stream.
outputCounter = new CountingStream(s);
// Sometimes the incoming "raw" output stream is already a CountingStream.
// Doesn't matter. Wrap it with a counter anyway. We need to count at both levels.
if (streamLength != 0L)
{
// Maybe wrap an encrypting stream around that:
// This will happen BEFORE output counting, and AFTER deflation, if encryption
// is used.
encryptor = MaybeApplyEncryption(outputCounter);
// Maybe wrap a DeflateStream around that.
// This will happen BEFORE encryption (if any) as we write data out.
deflater = MaybeApplyDeflation(encryptor, streamLength);
}
else
{
encryptor = deflater = outputCounter;
}
// Wrap a CrcCalculatorStream around that.
// This will happen BEFORE deflation (if any) as we write data out.
output = new Ionic.Zlib.CrcCalculatorStream(deflater, true);
}
private Stream MaybeApplyDeflation(Stream s, long streamLength)
{
if (_CompressionMethod == 0x08 && CompressionLevel != Ionic.Zlib.CompressionLevel.None)
{
#if !NETCF
// ParallelDeflateThreshold == 0 means ALWAYS use parallel deflate
// ParallelDeflateThreshold == -1L means NEVER use parallel deflate
// Other values specify the
if (_container.ParallelDeflateThreshold == 0L ||
(streamLength > _container.ParallelDeflateThreshold &&
_container.ParallelDeflateThreshold > 0L))
{
// This is sort of hacky.
//
// It's expensive to create a ParallelDeflateOutputStream, because
// of the large memory buffers. But the class is unlike most Stream
// classes in that it can be re-used, so the caller can compress
// multiple files with it, one file at a time. The key is to call
// Reset() on it, in between uses.
//
// The ParallelDeflateOutputStream is attached to the container
// itself - there is just one for the entire ZipFile or
// ZipOutputStream. So it gets created once, per save, and then
// re-used many times.
//
// This approach will break when we go to a "paral1lel save"
// approach, where multiple entries within the zip file are being
// compressed and saved at the same time. But for now it's ok.
//
// instantiate the ParallelDeflateOutputStream
if (_container.ParallelDeflater == null)
{
_container.ParallelDeflater =
new Ionic.Zlib.ParallelDeflateOutputStream(s,
CompressionLevel,
_container.Strategy,
true);
// can set the codec buffer size only before the first call to Write().
if (_container.CodecBufferSize > 0)
_container.ParallelDeflater.BufferSize = _container.CodecBufferSize;
}
// reset it with the new stream
Ionic.Zlib.ParallelDeflateOutputStream o1 = _container.ParallelDeflater;
o1.Reset(s);
return o1;
}
#endif
var o = new Ionic.Zlib.DeflateStream(s, Ionic.Zlib.CompressionMode.Compress,
CompressionLevel,
true);
if (_container.CodecBufferSize > 0)
o.BufferSize = _container.CodecBufferSize;
o.Strategy = _container.Strategy;
return o;
}
return s;
}
private Stream MaybeApplyEncryption(Stream s)
{
if (Encryption == EncryptionAlgorithm.PkzipWeak)
{
TraceWriteLine("MaybeApplyEncryption: e({0}) PKZIP", FileName);
return new ZipCipherStream(s, _zipCrypto_forWrite, CryptoMode.Encrypt);
}
#if AESCRYPTO
if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
TraceWriteLine("MaybeApplyEncryption: e({0}) AES", FileName);
return new WinZipAesCipherStream(s, _aesCrypto_forWrite, CryptoMode.Encrypt);
}
#endif
TraceWriteLine("MaybeApplyEncryption: e({0}) None", FileName);
return s;
}
private void OnZipErrorWhileSaving(Exception e)
{
if (_container.ZipFile != null)
_ioOperationCanceled = _container.ZipFile.OnZipErrorSaving(this, e);
}
internal void Write(Stream s)
{
bool done = false;
do
{
// In some cases the source for the zip entry data is a zip file
// (the app is updating a zip file). In some of those cases, some
// of the zip entries may be modified. Changes to the FileName,
// CompressionMethod CompressionLevel, and so on. Some of these
// changes require a "re-stream" - the old entry data must be
// maybe decrypted, maybe decompressed, then maybe re-compressed
// and maybe re-encrypted. This is true for changes in
// CompressionMethod or CompressionLevel. Some changes though,
// require an update only to metadata. A change in the entry
// name, or a new comment are examples of the latter. In some
// cases, the entry hasn't changed at all and can be simply copied
// as a block.
// This test checks if the source for the entry data is a zip file, and
// if a restream is necessary. If NOT, then it just copies through
// one entry, potentially changing the metadata.
if (_Source == ZipEntrySource.ZipFile && !_restreamRequiredOnSave)
{
CopyThroughOneEntry(s);
return;
}
// Ok, the source for this entry is not a previously created zip file, or
// the settings whave changed in important ways and therefore we will need to
// process the bytestream (compute crc, maybe compress, maybe encrypt) in
// order to create the zip.
//
// We do this in potentially 2 passes: The first time we do it as requested, maybe
// with compression and maybe encryption. If that causes the bytestream to inflate
// in size, and if compression was on, then we turn off compression and do it again.
try
{
if (IsDirectory)
{
WriteHeader(s, 1);
// nothing more to write
StoreRelativeOffset();
_entryRequiresZip64 = new Nullable<bool>(_RelativeOffsetOfLocalHeader >= 0xFFFFFFFF);
_OutputUsesZip64 = new Nullable<bool>(_container.Zip64 == Zip64Option.Always || _entryRequiresZip64.Value);
// handle case for split archives
var zss = s as ZipSegmentedStream;
if (zss != null)
_diskNumber = zss.CurrentSegment;
return;
}
bool readAgain = true;
int nCycles = 0;
do
{
nCycles++;
WriteHeader(s, nCycles);
// now, write the actual file data. (incl the encrypted header)
_EmitOne(s);
// The file data has now been written to the stream, and
// the file pointer is positioned directly after file data.
if (nCycles > 1) readAgain = false;
else if (!s.CanSeek) readAgain = false;
else readAgain = WantReadAgain();
if (readAgain)
{
// Seek back in the raw output stream, to the beginning of the file
// data for this entry.
// handle case for split archives
var zss = s as ZipSegmentedStream;
if (zss != null)
{
// Console.WriteLine("***_diskNumber/first: {0}", _diskNumber);
// Console.WriteLine("***_diskNumber/current: {0}", zss.CurrentSegment);
zss.TruncateBackward(_diskNumber, _RelativeOffsetOfLocalHeader);
}
else
// workitem 8098: ok (output).
s.Seek(_RelativeOffsetOfLocalHeader, SeekOrigin.Begin);
// If the last entry expands, we read again; but here, we must
// truncate the stream to prevent garbage data after the
// end-of-central-directory.
// workitem 8098: ok (output).
s.SetLength(s.Position);
// Adjust the count on the CountingStream as necessary.
var s1 = s as CountingStream;
if (s1 != null) s1.Adjust(_TotalEntrySize);
}
}
while (readAgain);
_skippedDuringSave = false;
done = true;
}
catch (System.Exception exc1)
{
ZipErrorAction orig = this.ZipErrorAction;
int loop = 0;
do
{
if (ZipErrorAction == ZipErrorAction.Throw)
throw;
if (ZipErrorAction == ZipErrorAction.Skip ||
ZipErrorAction == ZipErrorAction.Retry)
{
// must reset file pointer here.
if (!s.CanSeek) throw;
long p1 = s.Position;
s.Seek(_future_ROLH, SeekOrigin.Begin);
long p2 = s.Position;
s.SetLength(s.Position); // to prevent garbage if this is the last entry
var s1 = s as CountingStream;
if (s1 != null) s1.Adjust(p1 - p2);
if (ZipErrorAction == ZipErrorAction.Skip)
{
WriteStatus("Skipping file {0} (exception: {1})", LocalFileName, exc1.ToString());
_skippedDuringSave = true;
done = true;
}
else
this.ZipErrorAction = orig;
break;
}
if (loop > 0) throw;
if (ZipErrorAction == ZipErrorAction.InvokeErrorEvent)
{
OnZipErrorWhileSaving(exc1);
if (_ioOperationCanceled)
{
done = true;
break;
}
}
loop++;
}
while (true);
}
}
while (!done);
}
internal void StoreRelativeOffset()
{
_RelativeOffsetOfLocalHeader = _future_ROLH;
}
internal void NotifySaveComplete()
{
// When updating a zip file, there are two contexts for properties
// like Encryption or CompressionMethod - the values read from the
// original zip file, and the values used in the updated zip file.
// The _FromZipFile versions are the originals. At the end of a save,
// these values are the same. So we need to update them. This takes
// care of the boundary case where a single zipfile instance can be
// saved multiple times, with distinct changes to the properties on
// the entries, in between each Save(). Obviously an edge case, but
// it's good to take care of it.
_Encryption_FromZipFile = _Encryption;
_CompressionMethod_FromZipFile = _CompressionMethod;
_restreamRequiredOnSave = false;
_metadataChanged = false;
_Source = ZipEntrySource.None;
}
private void _EmitOne(Stream outstream)
{
WriteSecurityMetadata(outstream);
// write the (potentially compressed, potentially encrypted) file data
_WriteEntryData(outstream);
// track total entry size (including the trailing descriptor and MAC)
_TotalEntrySize = _LengthOfHeader + _CompressedFileDataSize + _LengthOfTrailer;
}
internal void WriteSecurityMetadata(Stream outstream)
{
string pwd = this._Password;
// special handling for source == ZipFile.
// Want to support the case where we re-stream an encrypted entry. This will involve,
// at runtime, reading, decrypting, and decompressing from the original zip file, then
// compressing, encrypting, and writing to the output zip file.
// If that's what we're doing, and the password hasn't been set on the entry,
// we use the container (ZipFile/ZipOutputStream) password to decrypt.
// This test here says to use the container password to re-encrypt, as well,
// with that password, if the entry password is null.
if (this._Source == ZipEntrySource.ZipFile && pwd == null)
pwd = this._container.Password;
if (pwd == null)
{
_zipCrypto_forWrite = null;
#if AESCRYPTO
_aesCrypto_forWrite = null;
#endif
return;
}
TraceWriteLine("WriteSecurityMetadata: e({0}) crypto({1}) pw({2})",
FileName, Encryption.ToString(), pwd);
if (Encryption == EncryptionAlgorithm.PkzipWeak)
{
// If PKZip (weak) encryption is in use, then the encrypted entry data
// is preceded by 12-byte "encryption header" for the entry.
_zipCrypto_forWrite = ZipCrypto.ForWrite(pwd);
// generate the random 12-byte header:
var rnd = new System.Random();
byte[] encryptionHeader = new byte[12];
rnd.NextBytes(encryptionHeader);
// workitem 8271
if ((this._BitField & 0x0008) == 0x0008)
{
// In the case that bit 3 of the general purpose bit flag is set to
// indicate the presence of a 'data descriptor' (signature
// 0x08074b50), the last byte of the decrypted header is sometimes
// compared with the high-order byte of the lastmodified time,
// rather than the high-order byte of the CRC, to verify the
// password.
//
// This is not documented in the PKWare Appnote.txt.
// This was discovered this by analysis of the Crypt.c source file in the
// InfoZip library
// http://www.info-zip.org/pub/infozip/
// Also, winzip insists on this!
_TimeBlob = Ionic.Zip.SharedUtilities.DateTimeToPacked(LastModified);
encryptionHeader[11] = (byte)((this._TimeBlob >> 8) & 0xff);
}
else
{
// When bit 3 is not set, the CRC value is required before
// encryption of the file data begins. In this case there is no way
// around it: must read the stream in its entirety to compute the
// actual CRC before proceeding.
FigureCrc32();
encryptionHeader[11] = (byte)((this._Crc32 >> 24) & 0xff);
}
// Encrypt the random header, INCLUDING the final byte which is either
// the high-order byte of the CRC32, or the high-order byte of the
// _TimeBlob. Must do this BEFORE encrypting the file data. This
// step changes the state of the cipher, or in the words of the PKZIP
// spec, it "further initializes" the cipher keys.
byte[] cipherText = _zipCrypto_forWrite.EncryptMessage(encryptionHeader, encryptionHeader.Length);
// Write the ciphered bonafide encryption header.
outstream.Write(cipherText, 0, cipherText.Length);
_LengthOfHeader += cipherText.Length; // 12 bytes
}
#if AESCRYPTO
else if (Encryption == EncryptionAlgorithm.WinZipAes128 ||
Encryption == EncryptionAlgorithm.WinZipAes256)
{
// If WinZip AES encryption is in use, then the encrypted entry data is
// preceded by a variable-sized Salt and a 2-byte "password
// verification" value for the entry.
int keystrength = GetKeyStrengthInBits(Encryption);
_aesCrypto_forWrite = WinZipAesCrypto.Generate(pwd, keystrength);
outstream.Write(_aesCrypto_forWrite.Salt, 0, _aesCrypto_forWrite._Salt.Length);
outstream.Write(_aesCrypto_forWrite.GeneratedPV, 0, _aesCrypto_forWrite.GeneratedPV.Length);
_LengthOfHeader += _aesCrypto_forWrite._Salt.Length + _aesCrypto_forWrite.GeneratedPV.Length;
TraceWriteLine("WriteSecurityMetadata: AES e({0}) keybits({1}) _LOH({2})",
FileName, keystrength, _LengthOfHeader);
}
#endif
}
private void CopyThroughOneEntry(Stream outstream)
{
// Just read the entry from the existing input zipfile and write to the output.
// But, if metadata has changed (like file times or attributes), or if the ZIP64
// option has changed, we can re-stream the entry data but must recompute the
// metadata.
if (this.LengthOfHeader == 0)
throw new BadStateException("Bad header length.");
// is it necessaty to re-constitute new metadata for this entry?
bool needRecompute = _metadataChanged ||
(_InputUsesZip64 && _container.UseZip64WhenSaving == Zip64Option.Never) ||
(!_InputUsesZip64 && _container.UseZip64WhenSaving == Zip64Option.Always);
if (needRecompute)
CopyThroughWithRecompute(outstream);
else
CopyThroughWithNoChange(outstream);
// zip64 housekeeping
_entryRequiresZip64 = new Nullable<bool>
(_CompressedSize >= 0xFFFFFFFF || _UncompressedSize >= 0xFFFFFFFF ||
_RelativeOffsetOfLocalHeader >= 0xFFFFFFFF
);
_OutputUsesZip64 = new Nullable<bool>(_container.Zip64 == Zip64Option.Always || _entryRequiresZip64.Value);
}
private void CopyThroughWithRecompute(Stream outstream)
{
int n;
byte[] bytes = new byte[BufferSize];
var input = new CountingStream(this.ArchiveStream);
long origRelativeOffsetOfHeader = _RelativeOffsetOfLocalHeader;
// The header length may change due to rename of file, add a comment, etc.
// We need to retain the original.
int origLengthOfHeader = LengthOfHeader; // including crypto bytes!
// WriteHeader() has the side effect of changing _RelativeOffsetOfLocalHeader
// and setting _LengthOfHeader. While ReadHeader() reads the crypto header if
// present, WriteHeader() does not write the crypto header.
WriteHeader(outstream, 0);
StoreRelativeOffset();
if (!this.FileName.EndsWith("/"))
{
// Not a directory; there is file data.
// Seek to the beginning of the entry data in the input stream.
long pos = origRelativeOffsetOfHeader + origLengthOfHeader;
int len = GetLengthOfCryptoHeaderBytes(_Encryption_FromZipFile);
pos -= len; // want to keep the crypto header
_LengthOfHeader += len;
input.Seek(pos, SeekOrigin.Begin);
// copy through everything after the header to the output stream
long remaining = this._CompressedSize;
while (remaining > 0)
{
len = (remaining > bytes.Length) ? bytes.Length : (int)remaining;
// read
n = input.Read(bytes, 0, len);
//_CheckRead(n);
// write
outstream.Write(bytes, 0, n);
remaining -= n;
OnWriteBlock(input.BytesRead, this._CompressedSize);
if (_ioOperationCanceled)
break;
}
// bit 3 descriptor
if ((this._BitField & 0x0008) == 0x0008)
{
int size = 16;
if (_InputUsesZip64) size += 8;
byte[] Descriptor = new byte[size];
input.Read(Descriptor, 0, size);
if (_InputUsesZip64 && _container.UseZip64WhenSaving == Zip64Option.Never)
{
// original descriptor was 24 bytes, now we need 16.
// Must check for underflow here.
// signature + CRC.
outstream.Write(Descriptor, 0, 8);
// Compressed
if (_CompressedSize > 0xFFFFFFFF)
throw new InvalidOperationException("ZIP64 is required");
outstream.Write(Descriptor, 8, 4);
// UnCompressed
if (_UncompressedSize > 0xFFFFFFFF)
throw new InvalidOperationException("ZIP64 is required");
outstream.Write(Descriptor, 16, 4);
_LengthOfTrailer -= 8;
}
else if (!_InputUsesZip64 && _container.UseZip64WhenSaving == Zip64Option.Always)
{
// original descriptor was 16 bytes, now we need 24
// signature + CRC
byte[] pad = new byte[4];
outstream.Write(Descriptor, 0, 8);
// Compressed
outstream.Write(Descriptor, 8, 4);
outstream.Write(pad, 0, 4);
// UnCompressed
outstream.Write(Descriptor, 12, 4);
outstream.Write(pad, 0, 4);
_LengthOfTrailer += 8;
}
else
{
// same descriptor on input and output. Copy it through.
outstream.Write(Descriptor, 0, size);
//_LengthOfTrailer += size;
}
}
}
_TotalEntrySize = _LengthOfHeader + _CompressedFileDataSize + _LengthOfTrailer;
}
private void CopyThroughWithNoChange(Stream outstream)
{
int n;
byte[] bytes = new byte[BufferSize];
var input = new CountingStream(this.ArchiveStream);
// seek to the beginning of the entry data in the input stream
input.Seek(this._RelativeOffsetOfLocalHeader, SeekOrigin.Begin);
if (this._TotalEntrySize == 0)
{
// We've never set the length of the entry.
// Set it here.
this._TotalEntrySize = this._LengthOfHeader + this._CompressedFileDataSize + _LengthOfTrailer;
// The CompressedSize includes all the leading metadata associated
// to encryption, if any, as well as the compressed data, or
// compressed-then-encrypted data, and the trailer in case of AES.
// The CompressedFileData size is the same, less the encryption
// framing data (12 bytes header for PKZip; 10/18 bytes header and
// 10 byte trailer for AES).
// The _LengthOfHeader includes all the zip entry header plus the
// crypto header, if any. The _LengthOfTrailer includes the
// 10-byte MAC for AES, where appropriate, and the bit-3
// Descriptor, where applicable.
}
// workitem 5616
// remember the offset, within the output stream, of this particular entry header.
// This may have changed if any of the other entries changed (eg, if a different
// entry was removed or added.)
var counter = outstream as CountingStream;
_RelativeOffsetOfLocalHeader = (counter != null)
? counter.ComputedPosition
: outstream.Position; // BytesWritten
// copy through the header, filedata, trailer, everything...
long remaining = this._TotalEntrySize;
while (remaining > 0)
{
int len = (remaining > bytes.Length) ? bytes.Length : (int)remaining;
// read
n = input.Read(bytes, 0, len);
//_CheckRead(n);
// write
outstream.Write(bytes, 0, n);
remaining -= n;
OnWriteBlock(input.BytesRead, this._TotalEntrySize);
if (_ioOperationCanceled)
break;
}
}
[System.Diagnostics.ConditionalAttribute("Trace")]
private void TraceWriteLine(string format, params object[] varParams)
{
lock (_outputLock)
{
int tid = System.Threading.Thread.CurrentThread.GetHashCode();
#if !NETCF
Console.ForegroundColor = (ConsoleColor)(tid % 8 + 8);
#endif
Console.Write("{0:000} ZipEntry.Write ", tid);
Console.WriteLine(format, varParams);
#if !NETCF
Console.ResetColor();
#endif
}
}
private object _outputLock = new Object();
}
}
Submit an article or tip