/// <summary> /// Process extra data fields updating the entry based on the contents. /// </summary> /// <param name="localHeader">True if the extra data fields should be handled /// for a local header, rather than for a central header. /// </param> internal void ProcessExtraData(bool localHeader) { var extraData = new ZipExtraData(this.extra); if (extraData.Find(0x0001)) { // Version required to extract is ignored here as some archivers dont set it correctly // in theory it should be version 45 or higher // The recorded size will change but remember that this is zip64. forceZip64_ = true; if (extraData.ValueLength < 4) { throw new ZipException("Extra data extended Zip64 information length is invalid"); } // (localHeader ||) was deleted, because actually there is no specific difference with reading sizes between local header & central directory // https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT // ... // 4.4 Explanation of fields // ... // 4.4.8 compressed size: (4 bytes) // 4.4.9 uncompressed size: (4 bytes) // // The size of the file compressed (4.4.8) and uncompressed, // (4.4.9) respectively. When a decryption header is present it // will be placed in front of the file data and the value of the // compressed file size will include the bytes of the decryption // header. If bit 3 of the general purpose bit flag is set, // these fields are set to zero in the local header and the // correct values are put in the data descriptor and // in the central directory. If an archive is in ZIP64 format // and the value in this field is 0xFFFFFFFF, the size will be // in the corresponding 8 byte ZIP64 extended information // extra field. When encrypting the central directory, if the // local header is not in ZIP64 format and general purpose bit // flag 13 is set indicating masking, the value stored for the // uncompressed size in the Local Header will be zero. // // Othewise there is problem with minizip implementation if (size == uint.MaxValue) { size = (ulong)extraData.ReadLong(); } if (compressedSize == uint.MaxValue) { compressedSize = (ulong)extraData.ReadLong(); } if (!localHeader && (offset == uint.MaxValue)) { offset = extraData.ReadLong(); } // Disk number on which file starts is ignored } else { if ( ((versionToExtract & 0xff) >= ZipConstants.VersionZip64) && ((size == uint.MaxValue) || (compressedSize == uint.MaxValue)) ) { throw new ZipException("Zip64 Extended information required but is missing."); } } DateTime = GetDateTime(extraData); if (method == CompressionMethod.WinZipAES) { ProcessAESExtraData(extraData); } }
/// <summary> /// Finishes the stream. This will write the central directory at the /// end of the zip file and flush the stream. /// </summary> /// <remarks> /// This is automatically called when the stream is closed. /// </remarks> /// <exception cref="System.IO.IOException"> /// An I/O error occurs. /// </exception> /// <exception cref="ZipException"> /// Comment exceeds the maximum length<br/> /// Entry name exceeds the maximum length /// </exception> public override void Finish() { if (entries == null) { return; } if (curEntry != null) { CloseEntry(); } long numEntries = entries.Count; long sizeEntries = 0; foreach (ZipEntry entry in entries) { WriteLeInt(ZipConstants.CentralHeaderSignature); WriteLeShort(ZipConstants.VersionMadeBy); WriteLeShort(entry.Version); WriteLeShort(entry.Flags); WriteLeShort((short)entry.CompressionMethodForHeader); WriteLeInt((int)entry.DosTime); WriteLeInt((int)entry.Crc); if (entry.IsZip64Forced() || (entry.CompressedSize >= uint.MaxValue)) { WriteLeInt(-1); } else { WriteLeInt((int)entry.CompressedSize); } if (entry.IsZip64Forced() || (entry.Size >= uint.MaxValue)) { WriteLeInt(-1); } else { WriteLeInt((int)entry.Size); } byte[] name = ZipStrings.ConvertToArray(entry.Flags, entry.Name); if (name.Length > 0xffff) { throw new ZipException("Name too long."); } var ed = new ZipExtraData(entry.ExtraData); if (entry.CentralHeaderRequiresZip64) { ed.StartNewEntry(); if (entry.IsZip64Forced() || (entry.Size >= 0xffffffff)) { ed.AddLeLong(entry.Size); } if (entry.IsZip64Forced() || (entry.CompressedSize >= 0xffffffff)) { ed.AddLeLong(entry.CompressedSize); } if (entry.Offset >= 0xffffffff) { ed.AddLeLong(entry.Offset); } ed.AddNewEntry(1); } else { ed.Delete(1); } if (entry.AESKeySize > 0) { AddExtraDataAES(entry, ed); } byte[] extra = ed.GetEntryData(); byte[] entryComment = (entry.Comment != null) ? ZipStrings.ConvertToArray(entry.Flags, entry.Comment) : new byte[0]; if (entryComment.Length > 0xffff) { throw new ZipException("Comment too long."); } WriteLeShort(name.Length); WriteLeShort(extra.Length); WriteLeShort(entryComment.Length); WriteLeShort(0); // disk number WriteLeShort(0); // internal file attributes // external file attributes if (entry.ExternalFileAttributes != -1) { WriteLeInt(entry.ExternalFileAttributes); } else { if (entry.IsDirectory) // mark entry as directory (from nikolam.AT.perfectinfo.com) { WriteLeInt(16); } else { WriteLeInt(0); } } if (entry.Offset >= uint.MaxValue) { WriteLeInt(-1); } else { WriteLeInt((int)entry.Offset); } if (name.Length > 0) { BaseOutputStream.Write(name, 0, name.Length); } if (extra.Length > 0) { BaseOutputStream.Write(extra, 0, extra.Length); } if (entryComment.Length > 0) { BaseOutputStream.Write(entryComment, 0, entryComment.Length); } sizeEntries += ZipConstants.CentralHeaderBaseSize + name.Length + extra.Length + entryComment.Length; } using (ZipHelperStream zhs = new ZipHelperStream(BaseOutputStream)) { zhs.WriteEndOfCentralDirectory(numEntries, sizeEntries, offset, zipComment); } entries = null; }
// Write the local file header // TODO: ZipHelperStream.WriteLocalHeader is not yet used and needs checking for ZipFile and ZipOuptutStream usage void WriteLocalHeader(ZipEntry entry, EntryPatchData patchData) { CompressionMethod method = entry.CompressionMethod; bool headerInfoAvailable = true; // How to get this? bool patchEntryHeader = false; WriteLEInt(ZipConstants.LocalHeaderSignature); WriteLEShort(entry.Version); WriteLEShort(entry.Flags); WriteLEShort((byte)method); WriteLEInt((int)entry.DosTime); if (headerInfoAvailable == true) { WriteLEInt((int)entry.Crc); if (entry.LocalHeaderRequiresZip64) { WriteLEInt(-1); WriteLEInt(-1); } else { WriteLEInt(entry.IsCrypted ? (int)entry.CompressedSize + ZipConstants.CryptoHeaderSize : (int)entry.CompressedSize); WriteLEInt((int)entry.Size); } } else { if (patchData != null) { patchData.CrcPatchOffset = stream_.Position; } WriteLEInt(0); // Crc if (patchData != null) { patchData.SizePatchOffset = stream_.Position; } // For local header both sizes appear in Zip64 Extended Information if (entry.LocalHeaderRequiresZip64 && patchEntryHeader) { WriteLEInt(-1); WriteLEInt(-1); } else { WriteLEInt(0); // Compressed size WriteLEInt(0); // Uncompressed size } } byte[] name = ZipConstants.ConvertToArray(entry.Flags, entry.Name); if (name.Length > 0xFFFF) { throw new ZipException("Entry name too long."); } var ed = new ZipExtraData(entry.ExtraData); if (entry.LocalHeaderRequiresZip64 && (headerInfoAvailable || patchEntryHeader)) { ed.StartNewEntry(); if (headerInfoAvailable) { ed.AddLeLong(entry.Size); ed.AddLeLong(entry.CompressedSize); } else { ed.AddLeLong(-1); ed.AddLeLong(-1); } ed.AddNewEntry(1); if (!ed.Find(1)) { throw new ZipException("Internal error cant find extra data"); } if (patchData != null) { patchData.SizePatchOffset = ed.CurrentReadIndex; } } else { ed.Delete(1); } byte[] extra = ed.GetEntryData(); WriteLEShort(name.Length); WriteLEShort(extra.Length); if (name.Length > 0) { stream_.Write(name, 0, name.Length); } if (entry.LocalHeaderRequiresZip64 && patchEntryHeader) { patchData.SizePatchOffset += stream_.Position; } if (extra.Length > 0) { stream_.Write(extra, 0, extra.Length); } }
/// <summary> /// Starts a new Zip entry. It automatically closes the previous /// entry if present. /// All entry elements bar name are optional, but must be correct if present. /// If the compression method is stored and the output is not patchable /// the compression for that entry is automatically changed to deflate level 0 /// </summary> /// <param name="entry"> /// the entry. /// </param> /// <exception cref="System.ArgumentNullException"> /// if entry passed is null. /// </exception> /// <exception cref="System.IO.IOException"> /// if an I/O error occured. /// </exception> /// <exception cref="System.InvalidOperationException"> /// if stream was finished /// </exception> /// <exception cref="ZipException"> /// Too many entries in the Zip file<br/> /// Entry name is too long<br/> /// Finish has already been called<br/> /// </exception> public void PutNextEntry(ZipEntry entry) { if (entry == null) { throw new ArgumentNullException(nameof(entry)); } if (entries == null) { throw new InvalidOperationException("ZipOutputStream was finished"); } if (curEntry != null) { CloseEntry(); } if (entries.Count == int.MaxValue) { throw new ZipException("Too many entries for Zip file"); } CompressionMethod method = entry.CompressionMethod; int compressionLevel = defaultCompressionLevel; // Clear flags that the library manages internally entry.Flags &= (int)GeneralBitFlags.UnicodeText; patchEntryHeader = false; bool headerInfoAvailable; // No need to compress - definitely no data. if (entry.Size == 0) { entry.CompressedSize = entry.Size; entry.Crc = 0; method = CompressionMethod.Stored; headerInfoAvailable = true; } else { headerInfoAvailable = (entry.Size >= 0) && entry.HasCrc && entry.CompressedSize >= 0; // Switch to deflation if storing isnt possible. if (method == CompressionMethod.Stored) { if (!headerInfoAvailable) { if (!CanPatchEntries) { // Can't patch entries so storing is not possible. method = CompressionMethod.Deflated; compressionLevel = 0; } } else // entry.size must be > 0 { entry.CompressedSize = entry.Size; headerInfoAvailable = entry.HasCrc; } } } if (headerInfoAvailable == false) { if (CanPatchEntries == false) { // Only way to record size and compressed size is to append a data descriptor // after compressed data. // Stored entries of this form have already been converted to deflating. entry.Flags |= 8; } else { patchEntryHeader = true; } } entry.Offset = offset; entry.CompressionMethod = (CompressionMethod)method; curMethod = method; sizePatchPos = -1; if ((useZip64_ == UseZip64.On) || ((entry.Size < 0) && (useZip64_ == UseZip64.Dynamic))) { entry.ForceZip64(); } // Write the local file header WriteLeInt(ZipConstants.LocalHeaderSignature); WriteLeShort(entry.Version); WriteLeShort(entry.Flags); WriteLeShort((byte)entry.CompressionMethodForHeader); WriteLeInt((int)entry.DosTime); // TODO: Refactor header writing. Its done in several places. if (headerInfoAvailable) { WriteLeInt((int)entry.Crc); if (entry.LocalHeaderRequiresZip64) { WriteLeInt(-1); WriteLeInt(-1); } else { WriteLeInt(entry.IsCrypted ? (int)entry.CompressedSize + ZipConstants.CryptoHeaderSize : (int)entry.CompressedSize); WriteLeInt((int)entry.Size); } } else { if (patchEntryHeader) { crcPatchPos = BaseOutputStream.Position; } WriteLeInt(0); // Crc if (patchEntryHeader) { sizePatchPos = BaseOutputStream.Position; } // For local header both sizes appear in Zip64 Extended Information if (entry.LocalHeaderRequiresZip64 || patchEntryHeader) { WriteLeInt(-1); WriteLeInt(-1); } else { WriteLeInt(0); // Compressed size WriteLeInt(0); // Uncompressed size } } byte[] name = ZipStrings.ConvertToArray(entry.Flags, entry.Name); if (name.Length > 0xFFFF) { throw new ZipException("Entry name too long."); } var ed = new ZipExtraData(entry.ExtraData); if (entry.LocalHeaderRequiresZip64) { ed.StartNewEntry(); if (headerInfoAvailable) { ed.AddLeLong(entry.Size); ed.AddLeLong(entry.CompressedSize); } else { ed.AddLeLong(-1); ed.AddLeLong(-1); } ed.AddNewEntry(1); if (!ed.Find(1)) { throw new ZipException("Internal error cant find extra data"); } if (patchEntryHeader) { sizePatchPos = ed.CurrentReadIndex; } } else { ed.Delete(1); } if (entry.AESKeySize > 0) { AddExtraDataAES(entry, ed); } byte[] extra = ed.GetEntryData(); WriteLeShort(name.Length); WriteLeShort(extra.Length); if (name.Length > 0) { BaseOutputStream.Write(name, 0, name.Length); } if (entry.LocalHeaderRequiresZip64 && patchEntryHeader) { sizePatchPos += BaseOutputStream.Position; } if (extra.Length > 0) { BaseOutputStream.Write(extra, 0, extra.Length); } offset += ZipConstants.LocalHeaderBaseSize + name.Length + extra.Length; // Fix offsetOfCentraldir for AES if (entry.AESKeySize > 0) { offset += entry.AESOverheadSize; } // Activate the entry. curEntry = entry; crc.Reset(); if (method == CompressionMethod.Deflated) { Deflater.Reset(); Deflater.SetLevel(compressionLevel); } size = 0; }