// There is a small chance that something very weird could happen here. The code calling into this function
// will ask for a value from the extra field if the field was masked with FF's. It's theoretically possible
// that a field was FF's legitimately, and the writer didn't decide to write the corresponding extra field.
// Also, at the same time, other fields were masked with FF's to indicate looking in the zip64 record.
// Then, the search for the zip64 record will fail because the expected size is wrong,
// and a nulled out Zip64ExtraField will be returned. Thus, even though there was Zip64 data,
// it will not be used. It is questionable whether this situation is possible to detect
// unlike the other functions that have try-pattern semantics, these functions always return a
// Zip64ExtraField. If a Zip64 extra field actually doesn't exist, all of the fields in the
// returned struct will be null
//
// If there are more than one Zip64 extra fields, we take the first one that has the expected size
//
public static Zip64ExtraField GetJustZip64Block(Stream extraFieldStream,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64Field;
using (BinaryReader reader = new BinaryReader(extraFieldStream))
{
ZipGenericExtraField currentExtraField;
while (ZipGenericExtraField.TryReadBlock(reader, extraFieldStream.Length, out currentExtraField))
{
if (TryGetZip64BlockFromGenericExtraField(currentExtraField, readUncompressedSize,
readCompressedSize, readLocalHeaderOffset, readStartDiskNumber, out zip64Field))
{
return(zip64Field);
}
}
}
zip64Field = new Zip64ExtraField();
zip64Field._compressedSize = null;
zip64Field._uncompressedSize = null;
zip64Field._localHeaderOffset = null;
zip64Field._startDiskNumber = null;
return(zip64Field);
}
public static Zip64ExtraField GetAndRemoveZip64Block(List <ZipGenericExtraField> extraFields, bool readUncompressedSize, bool readCompressedSize, bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64ExtraField = new Zip64ExtraField()
{
_compressedSize = null,
_uncompressedSize = null,
_localHeaderOffset = null,
_startDiskNumber = null
};
List <ZipGenericExtraField> zipGenericExtraFields = new List <ZipGenericExtraField>();
bool flag = false;
foreach (ZipGenericExtraField extraField in extraFields)
{
if (extraField.Tag != 1)
{
continue;
}
zipGenericExtraFields.Add(extraField);
if (flag || !Zip64ExtraField.TryGetZip64BlockFromGenericExtraField(extraField, readUncompressedSize, readCompressedSize, readLocalHeaderOffset, readStartDiskNumber, out zip64ExtraField))
{
continue;
}
flag = true;
}
foreach (ZipGenericExtraField zipGenericExtraField in zipGenericExtraFields)
{
extraFields.Remove(zipGenericExtraField);
}
return(zip64ExtraField);
}
public static Zip64ExtraField GetJustZip64Block(Stream extraFieldStream, bool readUncompressedSize, bool readCompressedSize, bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64ExtraField;
ZipGenericExtraField zipGenericExtraField;
Zip64ExtraField zip64ExtraField1;
using (BinaryReader binaryReader = new BinaryReader(extraFieldStream))
{
while (ZipGenericExtraField.TryReadBlock(binaryReader, extraFieldStream.Length, out zipGenericExtraField))
{
if (!Zip64ExtraField.TryGetZip64BlockFromGenericExtraField(zipGenericExtraField, readUncompressedSize, readCompressedSize, readLocalHeaderOffset, readStartDiskNumber, out zip64ExtraField))
{
continue;
}
zip64ExtraField1 = zip64ExtraField;
return(zip64ExtraField1);
}
zip64ExtraField = new Zip64ExtraField()
{
_compressedSize = null,
_uncompressedSize = null,
_localHeaderOffset = null,
_startDiskNumber = null
};
return(zip64ExtraField);
}
return(zip64ExtraField1);
}
public static List <ZipGenericExtraField> GetExtraFields(BinaryReader reader)
{
List <ZipGenericExtraField> zipGenericExtraFields;
reader.BaseStream.Seek((long)26, SeekOrigin.Current);
ushort num = reader.ReadUInt16();
ushort num1 = reader.ReadUInt16();
reader.BaseStream.Seek((long)num, SeekOrigin.Current);
using (Stream subReadStream = new SubReadStream(reader.BaseStream, reader.BaseStream.Position, (long)num1))
{
zipGenericExtraFields = ZipGenericExtraField.ParseExtraField(subReadStream);
}
Zip64ExtraField.RemoveZip64Blocks(zipGenericExtraFields);
return(zipGenericExtraFields);
}
public static Zip64ExtraField GetAndRemoveZip64Block(List <ZipGenericExtraField> extraFields,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64Field = new Zip64ExtraField();
zip64Field._compressedSize = null;
zip64Field._uncompressedSize = null;
zip64Field._localHeaderOffset = null;
zip64Field._startDiskNumber = null;
List <ZipGenericExtraField> markedForDelete = new List <ZipGenericExtraField>();
bool zip64FieldFound = false;
foreach (ZipGenericExtraField ef in extraFields)
{
if (ef.Tag == TagConstant)
{
markedForDelete.Add(ef);
if (!zip64FieldFound)
{
if (TryGetZip64BlockFromGenericExtraField(ef, readUncompressedSize, readCompressedSize,
readLocalHeaderOffset, readStartDiskNumber, out zip64Field))
{
zip64FieldFound = true;
}
}
}
}
foreach (ZipGenericExtraField ef in markedForDelete)
{
extraFields.Remove(ef);
}
return(zip64Field);
}
public static List <ZipGenericExtraField> GetExtraFields(BinaryReader reader)
{
// assumes that TrySkipBlock has already been called, so we don't have to validate twice
List <ZipGenericExtraField> result;
const int OffsetToFilenameLength = 26; // from the point before the signature
reader.BaseStream.Seek(OffsetToFilenameLength, SeekOrigin.Current);
ushort filenameLength = reader.ReadUInt16();
ushort extraFieldLength = reader.ReadUInt16();
reader.BaseStream.Seek(filenameLength, SeekOrigin.Current);
using (Stream str = new SubReadStream(reader.BaseStream, reader.BaseStream.Position, extraFieldLength))
{
result = ZipGenericExtraField.ParseExtraField(str);
}
Zip64ExtraField.RemoveZip64Blocks(result);
return(result);
}
// return value is true if we allocated an extra field for 64 bit headers, un/compressed size
private bool WriteLocalFileHeader(bool isEmptyFile)
{
BinaryWriter writer = new BinaryWriter(_archive.ArchiveStream);
// _entryname only gets set when we read in or call moveTo. MoveTo does a check, and
// reading in should not be able to produce an entryname longer than ushort.MaxValue
Debug.Assert(_storedEntryNameBytes.Length <= ushort.MaxValue);
// decide if we need the Zip64 extra field:
Zip64ExtraField zip64ExtraField = new Zip64ExtraField();
bool zip64Used = false;
uint compressedSizeTruncated, uncompressedSizeTruncated;
// if we already know that we have an empty file don't worry about anything, just do a straight shot of the header
if (isEmptyFile)
{
CompressionMethod = CompressionMethodValues.Stored;
compressedSizeTruncated = 0;
uncompressedSizeTruncated = 0;
Debug.Assert(_compressedSize == 0);
Debug.Assert(_uncompressedSize == 0);
Debug.Assert(_crc32 == 0);
}
else
{
// if we have a non-seekable stream, don't worry about sizes at all, and just set the right bit
// if we are using the data descriptor, then sizes and crc should be set to 0 in the header
if (_archive.Mode == ZipArchiveMode.Create && _archive.ArchiveStream.CanSeek == false && !isEmptyFile)
{
_generalPurposeBitFlag |= BitFlagValues.DataDescriptor;
zip64Used = false;
compressedSizeTruncated = 0;
uncompressedSizeTruncated = 0;
// the crc should not have been set if we are in create mode, but clear it just to be sure
Debug.Assert(_crc32 == 0);
}
else // if we are not in streaming mode, we have to decide if we want to write zip64 headers
{
if (SizesTooLarge()
#if DEBUG_FORCE_ZIP64
|| (_archive._forceZip64 && _archive.Mode == ZipArchiveMode.Update)
#endif
)
{
zip64Used = true;
compressedSizeTruncated = ZipHelper.Mask32Bit;
uncompressedSizeTruncated = ZipHelper.Mask32Bit;
// prepare Zip64 extra field object. If we have one of the sizes, the other must go in there
zip64ExtraField.CompressedSize = _compressedSize;
zip64ExtraField.UncompressedSize = _uncompressedSize;
VersionToExtractAtLeast(ZipVersionNeededValues.Zip64);
}
else
{
zip64Used = false;
compressedSizeTruncated = (uint)_compressedSize;
uncompressedSizeTruncated = (uint)_uncompressedSize;
}
}
}
// save offset
_offsetOfLocalHeader = writer.BaseStream.Position;
// calculate extra field. if zip64 stuff + original extraField aren't going to fit, dump the original extraField, because this is more important
int bigExtraFieldLength = (zip64Used ? zip64ExtraField.TotalSize : 0)
+ (_lhUnknownExtraFields != null ? ZipGenericExtraField.TotalSize(_lhUnknownExtraFields) : 0);
ushort extraFieldLength;
if (bigExtraFieldLength > ushort.MaxValue)
{
extraFieldLength = (ushort)(zip64Used ? zip64ExtraField.TotalSize : 0);
_lhUnknownExtraFields = null;
}
else
{
extraFieldLength = (ushort)bigExtraFieldLength;
}
// write header
writer.Write(ZipLocalFileHeader.SignatureConstant);
writer.Write((ushort)_versionToExtract);
writer.Write((ushort)_generalPurposeBitFlag);
writer.Write((ushort)CompressionMethod);
writer.Write(ZipHelper.DateTimeToDosTime(_lastModified.DateTime)); // uint
writer.Write(_crc32); // uint
writer.Write(compressedSizeTruncated); // uint
writer.Write(uncompressedSizeTruncated); // uint
writer.Write((ushort)_storedEntryNameBytes.Length);
writer.Write(extraFieldLength); // ushort
writer.Write(_storedEntryNameBytes);
if (zip64Used)
{
zip64ExtraField.WriteBlock(_archive.ArchiveStream);
}
if (_lhUnknownExtraFields != null)
{
ZipGenericExtraField.WriteAllBlocks(_lhUnknownExtraFields, _archive.ArchiveStream);
}
return(zip64Used);
}
private static bool TryGetZip64BlockFromGenericExtraField(ZipGenericExtraField extraField,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber,
out Zip64ExtraField zip64Block)
{
zip64Block = new Zip64ExtraField();
zip64Block._compressedSize = null;
zip64Block._uncompressedSize = null;
zip64Block._localHeaderOffset = null;
zip64Block._startDiskNumber = null;
if (extraField.Tag != TagConstant)
{
return(false);
}
// this pattern needed because nested using blocks trigger CA2202
MemoryStream?ms = null;
try
{
ms = new MemoryStream(extraField.Data);
using (BinaryReader reader = new BinaryReader(ms))
{
ms = null;
zip64Block._size = extraField.Size;
ushort expectedSize = 0;
if (readUncompressedSize)
{
expectedSize += 8;
}
if (readCompressedSize)
{
expectedSize += 8;
}
if (readLocalHeaderOffset)
{
expectedSize += 8;
}
if (readStartDiskNumber)
{
expectedSize += 4;
}
// if it is not the expected size, perhaps there is another extra field that matches
if (expectedSize != zip64Block._size)
{
return(false);
}
if (readUncompressedSize)
{
zip64Block._uncompressedSize = reader.ReadInt64();
}
if (readCompressedSize)
{
zip64Block._compressedSize = reader.ReadInt64();
}
if (readLocalHeaderOffset)
{
zip64Block._localHeaderOffset = reader.ReadInt64();
}
if (readStartDiskNumber)
{
zip64Block._startDiskNumber = reader.ReadInt32();
}
// original values are unsigned, so implies value is too big to fit in signed integer
if (zip64Block._uncompressedSize < 0)
{
throw new InvalidDataException(SR.FieldTooBigUncompressedSize);
}
if (zip64Block._compressedSize < 0)
{
throw new InvalidDataException(SR.FieldTooBigCompressedSize);
}
if (zip64Block._localHeaderOffset < 0)
{
throw new InvalidDataException(SR.FieldTooBigLocalHeaderOffset);
}
if (zip64Block._startDiskNumber < 0)
{
throw new InvalidDataException(SR.FieldTooBigStartDiskNumber);
}
return(true);
}
}
finally
{
if (ms != null)
{
ms.Dispose();
}
}
}
//if saveExtraFieldsAndComments is false, FileComment and ExtraFields will be null
//in either case, the zip64 extra field info will be incorporated into other fields
static public Boolean TryReadBlock(BinaryReader reader, Boolean saveExtraFieldsAndComments, out ZipCentralDirectoryFileHeader header)
{
header = new ZipCentralDirectoryFileHeader();
if (reader.ReadUInt32() != SignatureConstant)
{
return(false);
}
header.VersionMadeBy = reader.ReadUInt16();
header.VersionNeededToExtract = reader.ReadUInt16();
header.GeneralPurposeBitFlag = reader.ReadUInt16();
header.CompressionMethod = reader.ReadUInt16();
header.LastModified = reader.ReadUInt32();
header.Crc32 = reader.ReadUInt32();
UInt32 compressedSizeSmall = reader.ReadUInt32();
UInt32 uncompressedSizeSmall = reader.ReadUInt32();
header.FilenameLength = reader.ReadUInt16();
header.ExtraFieldLength = reader.ReadUInt16();
header.FileCommentLength = reader.ReadUInt16();
UInt16 diskNumberStartSmall = reader.ReadUInt16();
header.InternalFileAttributes = reader.ReadUInt16();
header.ExternalFileAttributes = reader.ReadUInt32();
UInt32 relativeOffsetOfLocalHeaderSmall = reader.ReadUInt32();
header.Filename = reader.ReadBytes(header.FilenameLength);
Boolean uncompressedSizeInZip64 = uncompressedSizeSmall == ZipHelper.Mask32Bit;
Boolean compressedSizeInZip64 = compressedSizeSmall == ZipHelper.Mask32Bit;
Boolean relativeOffsetInZip64 = relativeOffsetOfLocalHeaderSmall == ZipHelper.Mask32Bit;
Boolean diskNumberStartInZip64 = diskNumberStartSmall == ZipHelper.Mask16Bit;
Zip64ExtraField zip64;
using (Stream str = new SubReadStream(reader.BaseStream, reader.BaseStream.Position, header.ExtraFieldLength))
{
if (saveExtraFieldsAndComments)
{
header.ExtraFields = ZipGenericExtraField.ParseExtraField(str);
zip64 = Zip64ExtraField.GetAndRemoveZip64Block(header.ExtraFields,
uncompressedSizeInZip64, compressedSizeInZip64,
relativeOffsetInZip64, diskNumberStartInZip64);
}
else
{
header.ExtraFields = null;
zip64 = Zip64ExtraField.GetJustZip64Block(str,
uncompressedSizeInZip64, compressedSizeInZip64,
relativeOffsetInZip64, diskNumberStartInZip64);
}
}
if (saveExtraFieldsAndComments)
{
header.FileComment = reader.ReadBytes(header.FileCommentLength);
}
else
{
reader.BaseStream.Position += header.FileCommentLength;
header.FileComment = null;
}
header.UncompressedSize = zip64.UncompressedSize == null
? uncompressedSizeSmall
: zip64.UncompressedSize.Value;
header.CompressedSize = zip64.CompressedSize == null
? compressedSizeSmall
: zip64.CompressedSize.Value;
header.RelativeOffsetOfLocalHeader = zip64.LocalHeaderOffset == null
? relativeOffsetOfLocalHeaderSmall
: zip64.LocalHeaderOffset.Value;
header.DiskNumberStart = zip64.StartDiskNumber == null
? diskNumberStartSmall
: zip64.StartDiskNumber.Value;
return(true);
}
private bool WriteLocalFileHeader(bool isEmptyFile)
{
uint num;
uint num1;
ushort num2;
ushort totalSize;
ushort num3;
object obj;
BinaryWriter binaryWriter = new BinaryWriter(this._archive.ArchiveStream);
Zip64ExtraField nullable = new Zip64ExtraField();
bool flag = false;
if (isEmptyFile)
{
this.CompressionMethod = ZipArchiveEntry.CompressionMethodValues.Stored;
num = 0;
num1 = 0;
}
else if (this._archive.Mode == ZipArchiveMode.Create && !this._archive.ArchiveStream.CanSeek && !isEmptyFile)
{
this._generalPurposeBitFlag |= ZipArchiveEntry.BitFlagValues.DataDescriptor;
flag = false;
num = 0;
num1 = 0;
}
else if (!this.SizesTooLarge())
{
flag = false;
num = (uint)this._compressedSize;
num1 = (uint)this._uncompressedSize;
}
else
{
flag = true;
num = -1;
num1 = -1;
nullable.CompressedSize = new long?(this._compressedSize);
nullable.UncompressedSize = new long?(this._uncompressedSize);
this.VersionToExtractAtLeast(ZipVersionNeededValues.Zip64);
}
this._offsetOfLocalHeader = binaryWriter.BaseStream.Position;
if (flag)
{
totalSize = nullable.TotalSize;
}
else
{
totalSize = 0;
}
if (this._lhUnknownExtraFields != null)
{
num3 = (ushort)ZipGenericExtraField.TotalSize(this._lhUnknownExtraFields);
}
else
{
num3 = 0;
}
int num4 = totalSize + num3;
if (num4 <= 65535)
{
num2 = (ushort)num4;
}
else
{
if (flag)
{
obj = nullable.TotalSize;
}
else
{
obj = null;
}
num2 = (ushort)obj;
this._lhUnknownExtraFields = null;
}
binaryWriter.Write((uint)67324752);
binaryWriter.Write((ushort)this._versionToExtract);
binaryWriter.Write((ushort)this._generalPurposeBitFlag);
binaryWriter.Write((ushort)this.CompressionMethod);
binaryWriter.Write(ZipHelper.DateTimeToDosTime(this._lastModified.DateTime));
binaryWriter.Write(this._crc32);
binaryWriter.Write(num);
binaryWriter.Write(num1);
binaryWriter.Write((ushort)((int)this._storedEntryNameBytes.Length));
binaryWriter.Write(num2);
binaryWriter.Write(this._storedEntryNameBytes);
if (flag)
{
nullable.WriteBlock(this._archive.ArchiveStream);
}
if (this._lhUnknownExtraFields != null)
{
ZipGenericExtraField.WriteAllBlocks(this._lhUnknownExtraFields, this._archive.ArchiveStream);
}
return(flag);
}
/* There is a small chance that something very weird could happen here. The code calling into this function
* will ask for a value from the extra field if the field was masked with FF's. It's theoretically possible
* that a field was FF's legitimately, and the writer didn't decide to write the corresponding extra field.
* Also, at the same time, other fields were masked with FF's to indicate looking in the zip64 record.
* Then, the search for the zip64 record will fail because the expected size is wrong,
* and a nulled out Zip64ExtraField will be returned. Thus, even though there was Zip64 data,
* it will not be used. It is questionable whether this situation is possible to detect
*/
/* unlike the other functions that have try-pattern semantics, these functions always return a
* Zip64ExtraField. If a Zip64 extra field actually doesn't exist, all of the fields in the
* returned struct will be null
*
* If there are more than one Zip64 extra fields, we take the first one that has the expected size
*/
public static Zip64ExtraField GetJustZip64Block(Stream extraFieldStream,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64Field;
using (BinaryReader reader = new BinaryReader(extraFieldStream))
{
ZipGenericExtraField currentExtraField;
while (ZipGenericExtraField.TryReadBlock(reader, extraFieldStream.Length, out currentExtraField))
{
if (TryGetZip64BlockFromGenericExtraField(currentExtraField, readUncompressedSize,
readCompressedSize, readLocalHeaderOffset, readStartDiskNumber, out zip64Field))
{
return zip64Field;
}
}
}
zip64Field = new Zip64ExtraField();
zip64Field._compressedSize = null;
zip64Field._uncompressedSize = null;
zip64Field._localHeaderOffset = null;
zip64Field._startDiskNumber = null;
return zip64Field;
}
//return value is true if we allocated an extra field for 64 bit headers, un/compressed size
private Boolean WriteLocalFileHeader(Boolean isEmptyFile)
{
BinaryWriter writer = new BinaryWriter(_archive.ArchiveStream);
//_entryname only gets set when we read in or call moveTo. MoveTo does a check, and
//reading in should not be able to produce a entryname longer than UInt16.MaxValue
Debug.Assert(_storedEntryNameBytes.Length <= UInt16.MaxValue);
//decide if we need the Zip64 extra field:
Zip64ExtraField zip64ExtraField = new Zip64ExtraField();
Boolean zip64Used = false;
UInt32 compressedSizeTruncated, uncompressedSizeTruncated;
//if we already know that we have an empty file don't worry about anything, just do a straight shot of the header
if (isEmptyFile)
{
CompressionMethod = CompressionMethodValues.Stored;
compressedSizeTruncated = 0;
uncompressedSizeTruncated = 0;
Debug.Assert(_compressedSize == 0);
Debug.Assert(_uncompressedSize == 0);
Debug.Assert(_crc32 == 0);
}
else
{
//if we have a non-seekable stream, don't worry about sizes at all, and just set the right bit
//if we are using the data descriptor, then sizes and crc should be set to 0 in the header
if (_archive.Mode == ZipArchiveMode.Create && _archive.ArchiveStream.CanSeek == false && !isEmptyFile)
{
_generalPurposeBitFlag |= BitFlagValues.DataDescriptor;
zip64Used = false;
compressedSizeTruncated = 0;
uncompressedSizeTruncated = 0;
//the crc should not have been set if we are in create mode, but clear it just to be sure
Debug.Assert(_crc32 == 0);
}
else //if we are not in streaming mode, we have to decide if we want to write zip64 headers
{
if (SizesTooLarge()
#if DEBUG_FORCE_ZIP64
|| (_archive._forceZip64 && _archive.Mode == ZipArchiveMode.Update)
#endif
)
{
zip64Used = true;
compressedSizeTruncated = ZipHelper.Mask32Bit;
uncompressedSizeTruncated = ZipHelper.Mask32Bit;
//prepare Zip64 extra field object. If we have one of the sizes, the other must go in there
zip64ExtraField.CompressedSize = _compressedSize;
zip64ExtraField.UncompressedSize = _uncompressedSize;
VersionToExtractAtLeast(ZipVersionNeededValues.Zip64);
}
else
{
zip64Used = false;
compressedSizeTruncated = (UInt32)_compressedSize;
uncompressedSizeTruncated = (UInt32)_uncompressedSize;
}
}
}
//save offset
_offsetOfLocalHeader = writer.BaseStream.Position;
//calculate extra field. if zip64 stuff + original extraField aren't going to fit, dump the original extraField, because this is more important
Int32 bigExtraFieldLength = (zip64Used ? zip64ExtraField.TotalSize : 0)
+ (_lhUnknownExtraFields != null ? ZipGenericExtraField.TotalSize(_lhUnknownExtraFields) : 0);
UInt16 extraFieldLength;
if (bigExtraFieldLength > UInt16.MaxValue)
{
extraFieldLength = (UInt16)(zip64Used ? zip64ExtraField.TotalSize : 0);
_lhUnknownExtraFields = null;
}
else
{
extraFieldLength = (UInt16)bigExtraFieldLength;
}
//write header
writer.Write(ZipLocalFileHeader.SignatureConstant);
writer.Write((UInt16)_versionToExtract);
writer.Write((UInt16)_generalPurposeBitFlag);
writer.Write((UInt16)CompressionMethod);
writer.Write(ZipHelper.DateTimeToDosTime(_lastModified.DateTime)); //UInt32
writer.Write(_crc32); //UInt32
writer.Write(compressedSizeTruncated); //UInt32
writer.Write(uncompressedSizeTruncated); //UInt32
writer.Write((UInt16)_storedEntryNameBytes.Length);
writer.Write(extraFieldLength); //UInt16
writer.Write(_storedEntryNameBytes);
if (zip64Used)
zip64ExtraField.WriteBlock(_archive.ArchiveStream);
if (_lhUnknownExtraFields != null)
ZipGenericExtraField.WriteAllBlocks(_lhUnknownExtraFields, _archive.ArchiveStream);
return zip64Used;
}
internal void WriteCentralDirectoryFileHeader()
{
uint num;
uint num1;
uint num2;
ushort num3;
ushort totalSize;
ushort num4;
ushort length;
object obj;
BinaryWriter binaryWriter = new BinaryWriter(this._archive.ArchiveStream);
Zip64ExtraField nullable = new Zip64ExtraField();
bool flag = false;
if (!this.SizesTooLarge())
{
num = (uint)this._compressedSize;
num1 = (uint)this._uncompressedSize;
}
else
{
flag = true;
num = -1;
num1 = -1;
nullable.CompressedSize = new long?(this._compressedSize);
nullable.UncompressedSize = new long?(this._uncompressedSize);
}
if (this._offsetOfLocalHeader <= (ulong)-1)
{
num2 = (uint)this._offsetOfLocalHeader;
}
else
{
flag = true;
num2 = -1;
nullable.LocalHeaderOffset = new long?(this._offsetOfLocalHeader);
}
if (flag)
{
this.VersionToExtractAtLeast(ZipVersionNeededValues.Zip64);
}
if (flag)
{
totalSize = nullable.TotalSize;
}
else
{
totalSize = 0;
}
if (this._cdUnknownExtraFields != null)
{
num4 = (ushort)ZipGenericExtraField.TotalSize(this._cdUnknownExtraFields);
}
else
{
num4 = 0;
}
int num5 = totalSize + num4;
if (num5 <= 65535)
{
num3 = (ushort)num5;
}
else
{
if (flag)
{
obj = nullable.TotalSize;
}
else
{
obj = null;
}
num3 = (ushort)obj;
this._cdUnknownExtraFields = null;
}
binaryWriter.Write((uint)33639248);
binaryWriter.Write((ushort)this._versionToExtract);
binaryWriter.Write((ushort)this._versionToExtract);
binaryWriter.Write((ushort)this._generalPurposeBitFlag);
binaryWriter.Write((ushort)this.CompressionMethod);
binaryWriter.Write(ZipHelper.DateTimeToDosTime(this._lastModified.DateTime));
binaryWriter.Write(this._crc32);
binaryWriter.Write(num);
binaryWriter.Write(num1);
binaryWriter.Write((ushort)((int)this._storedEntryNameBytes.Length));
binaryWriter.Write(num3);
BinaryWriter binaryWriter1 = binaryWriter;
if (this._fileComment != null)
{
length = (ushort)((int)this._fileComment.Length);
}
else
{
length = 0;
}
binaryWriter1.Write(length);
binaryWriter.Write((ushort)0);
binaryWriter.Write((ushort)0);
binaryWriter.Write(this._externalFileAttr);
binaryWriter.Write(num2);
binaryWriter.Write(this._storedEntryNameBytes);
if (flag)
{
nullable.WriteBlock(this._archive.ArchiveStream);
}
if (this._cdUnknownExtraFields != null)
{
ZipGenericExtraField.WriteAllBlocks(this._cdUnknownExtraFields, this._archive.ArchiveStream);
}
if (this._fileComment != null)
{
binaryWriter.Write(this._fileComment);
}
}
private static bool TryGetZip64BlockFromGenericExtraField(ZipGenericExtraField extraField, bool readUncompressedSize, bool readCompressedSize, bool readLocalHeaderOffset, bool readStartDiskNumber, out Zip64ExtraField zip64Block)
{
bool flag;
zip64Block = new Zip64ExtraField()
{
_compressedSize = null,
_uncompressedSize = null,
_localHeaderOffset = null,
_startDiskNumber = null
};
if (extraField.Tag != 1)
{
return(false);
}
MemoryStream memoryStream = null;
try
{
memoryStream = new MemoryStream(extraField.Data);
using (BinaryReader binaryReader = new BinaryReader(memoryStream))
{
memoryStream = null;
zip64Block._size = extraField.Size;
ushort num = 0;
if (readUncompressedSize)
{
num = (ushort)(num + 8);
}
if (readCompressedSize)
{
num = (ushort)(num + 8);
}
if (readLocalHeaderOffset)
{
num = (ushort)(num + 8);
}
if (readStartDiskNumber)
{
num = (ushort)(num + 4);
}
if (num == zip64Block._size)
{
if (readUncompressedSize)
{
zip64Block._uncompressedSize = new long?(binaryReader.ReadInt64());
}
if (readCompressedSize)
{
zip64Block._compressedSize = new long?(binaryReader.ReadInt64());
}
if (readLocalHeaderOffset)
{
zip64Block._localHeaderOffset = new long?(binaryReader.ReadInt64());
}
if (readStartDiskNumber)
{
zip64Block._startDiskNumber = new int?(binaryReader.ReadInt32());
}
long?nullable = zip64Block._uncompressedSize;
long num1 = (long)0;
if ((nullable.GetValueOrDefault() < num1 ? nullable.HasValue : false))
{
throw new InvalidDataException(Messages.FieldTooBigUncompressedSize);
}
nullable = zip64Block._compressedSize;
num1 = (long)0;
if ((nullable.GetValueOrDefault() < num1 ? nullable.HasValue : false))
{
throw new InvalidDataException(Messages.FieldTooBigCompressedSize);
}
nullable = zip64Block._localHeaderOffset;
num1 = (long)0;
if ((nullable.GetValueOrDefault() < num1 ? nullable.HasValue : false))
{
throw new InvalidDataException(Messages.FieldTooBigLocalHeaderOffset);
}
int?nullable1 = zip64Block._startDiskNumber;
if ((nullable1.GetValueOrDefault() < 0 ? nullable1.HasValue : false))
{
throw new InvalidDataException(Messages.FieldTooBigStartDiskNumber);
}
flag = true;
}
else
{
flag = false;
}
}
}
finally
{
if (memoryStream != null)
{
memoryStream.Close();
}
}
return(flag);
}
//should only throw an exception in extremely exceptional cases because it is called from dispose
internal void WriteCentralDirectoryFileHeader()
{
//This part is simple, because we should definitely know the sizes by this time
BinaryWriter writer = new BinaryWriter(_archive.ArchiveStream);
//_entryname only gets set when we read in or call moveTo. MoveTo does a check, and
//reading in should not be able to produce a entryname longer than UInt16.MaxValue
Debug.Assert(_storedEntryNameBytes.Length <= UInt16.MaxValue);
//decide if we need the Zip64 extra field:
Zip64ExtraField zip64ExtraField = new Zip64ExtraField();
UInt32 compressedSizeTruncated, uncompressedSizeTruncated, offsetOfLocalHeaderTruncated;
Boolean zip64Needed = false;
if (SizesTooLarge()
#if DEBUG_FORCE_ZIP64
|| _archive._forceZip64
#endif
)
{
zip64Needed = true;
compressedSizeTruncated = ZipHelper.Mask32Bit;
uncompressedSizeTruncated = ZipHelper.Mask32Bit;
//If we have one of the sizes, the other must go in there as speced for LH, but not necessarily for CH, but we do it anyways
zip64ExtraField.CompressedSize = _compressedSize;
zip64ExtraField.UncompressedSize = _uncompressedSize;
}
else
{
compressedSizeTruncated = (UInt32)_compressedSize;
uncompressedSizeTruncated = (UInt32)_uncompressedSize;
}
if (_offsetOfLocalHeader > UInt32.MaxValue
#if DEBUG_FORCE_ZIP64
|| _archive._forceZip64
#endif
)
{
zip64Needed = true;
offsetOfLocalHeaderTruncated = ZipHelper.Mask32Bit;
//If we have one of the sizes, the other must go in there as speced for LH, but not necessarily for CH, but we do it anyways
zip64ExtraField.LocalHeaderOffset = _offsetOfLocalHeader;
}
else
{
offsetOfLocalHeaderTruncated = (UInt32)_offsetOfLocalHeader;
}
if (zip64Needed)
VersionToExtractAtLeast(ZipVersionNeededValues.Zip64);
//determine if we can fit zip64 extra field and original extra fields all in
Int32 bigExtraFieldLength = (zip64Needed ? zip64ExtraField.TotalSize : 0)
+ (_cdUnknownExtraFields != null ? ZipGenericExtraField.TotalSize(_cdUnknownExtraFields) : 0);
UInt16 extraFieldLength;
if (bigExtraFieldLength > UInt16.MaxValue)
{
extraFieldLength = (UInt16)(zip64Needed ? zip64ExtraField.TotalSize : 0);
_cdUnknownExtraFields = null;
}
else
{
extraFieldLength = (UInt16)bigExtraFieldLength;
}
writer.Write(ZipCentralDirectoryFileHeader.SignatureConstant); // Central directory file header signature (4 bytes)
writer.Write((byte)_versionMadeBySpecification); // Version made by Specification (version) (1 byte)
writer.Write((byte)CurrentZipPlatform); // Version made by Compatibility (type) (1 byte)
writer.Write((UInt16)_versionToExtract); // Minimum version needed to extract (2 bytes)
writer.Write((UInt16)_generalPurposeBitFlag); // General Purpose bit flag (2 bytes)
writer.Write((UInt16)CompressionMethod); // The Compression method (2 bytes)
writer.Write(ZipHelper.DateTimeToDosTime(_lastModified.DateTime)); // File last modification time and date (4 bytes)
writer.Write(_crc32); // CRC-32 (4 bytes)
writer.Write(compressedSizeTruncated); // Compressed Size (4 bytes)
writer.Write(uncompressedSizeTruncated); // Uncompressed Size (4 bytes)
writer.Write((UInt16)_storedEntryNameBytes.Length); // File Name Length (2 bytes)
writer.Write(extraFieldLength); // Extra Field Length (2 bytes)
// This should hold because of how we read it originally in ZipCentralDirectoryFileHeader:
Debug.Assert((_fileComment == null) || (_fileComment.Length <= UInt16.MaxValue));
writer.Write(_fileComment != null ? (UInt16)_fileComment.Length : (UInt16)0); //file comment length
writer.Write((UInt16)0); //disk number start
writer.Write((UInt16)0); //internal file attributes
writer.Write((UInt32)0); //external file attributes
writer.Write(offsetOfLocalHeaderTruncated); //offset of local header
writer.Write(_storedEntryNameBytes);
//write extra fields
if (zip64Needed)
zip64ExtraField.WriteBlock(_archive.ArchiveStream);
if (_cdUnknownExtraFields != null)
ZipGenericExtraField.WriteAllBlocks(_cdUnknownExtraFields, _archive.ArchiveStream);
if (_fileComment != null)
writer.Write(_fileComment);
}
public static bool TryValidateBlock(BinaryReader reader, ZipArchiveEntry entry)
{
const int OffsetToFilename = 26; // from the point after the signature
if (reader.ReadUInt32() != SignatureConstant)
{
return(false);
}
if (reader.BaseStream.Length < reader.BaseStream.Position + OffsetToFilename)
{
return(false);
}
reader.BaseStream.Seek(2, SeekOrigin.Current); // skipping minimum version (using min version from central directory header)
uint dataDescriptorBit = reader.ReadUInt16() & (uint)ZipArchiveEntry.BitFlagValues.DataDescriptor;
reader.BaseStream.Seek(10, SeekOrigin.Current); // skipping bytes used for Compression method (2 bytes), last modification time and date (4 bytes) and CRC (4 bytes)
long compressedSize = reader.ReadUInt32();
long uncompressedSize = reader.ReadUInt32();
int filenameLength = reader.ReadUInt16();
uint extraFieldLength = reader.ReadUInt16();
if (reader.BaseStream.Length < reader.BaseStream.Position + filenameLength + extraFieldLength)
{
return(false);
}
reader.BaseStream.Seek(filenameLength, SeekOrigin.Current); // skipping Filename
long endExtraFields = reader.BaseStream.Position + extraFieldLength;
if (dataDescriptorBit == 0)
{
bool isUncompressedSizeInZip64 = uncompressedSize == ZipHelper.Mask32Bit;
bool isCompressedSizeInZip64 = compressedSize == ZipHelper.Mask32Bit;
Zip64ExtraField zip64;
// Ideally we should also check if the minimumVersion is 64 bit or above, but there could zip files for which this version is not set correctly
if (isUncompressedSizeInZip64 || isCompressedSizeInZip64)
{
zip64 = Zip64ExtraField.GetJustZip64Block(new SubReadStream(reader.BaseStream, reader.BaseStream.Position, extraFieldLength), isUncompressedSizeInZip64, isCompressedSizeInZip64, false, false);
if (zip64.UncompressedSize != null)
{
uncompressedSize = zip64.UncompressedSize.Value;
}
if (zip64.CompressedSize != null)
{
compressedSize = zip64.CompressedSize.Value;
}
}
reader.BaseStream.AdvanceToPosition(endExtraFields);
}
else
{
if (reader.BaseStream.Length < reader.BaseStream.Position + extraFieldLength + entry.CompressedLength + 4)
{
return(false);
}
reader.BaseStream.Seek(extraFieldLength + entry.CompressedLength, SeekOrigin.Current); // seek to end of compressed file from which Data descriptor starts
uint dataDescriptorSignature = reader.ReadUInt32();
bool wasDataDescriptorSignatureRead = false;
int seekSize = 0;
if (dataDescriptorSignature == DataDescriptorSignature)
{
wasDataDescriptorSignatureRead = true;
seekSize = 4;
}
bool is64bit = entry._versionToExtract >= ZipVersionNeededValues.Zip64;
seekSize += (is64bit ? 8 : 4) * 2; // if Zip64 read by 8 bytes else 4 bytes 2 times (compressed and uncompressed size)
if (reader.BaseStream.Length < reader.BaseStream.Position + seekSize)
{
return(false);
}
// dataDescriptorSignature is optional, if it was the DataDescriptorSignature we need to skip CRC 4 bytes else we can assume CRC is alreadyskipped
if (wasDataDescriptorSignatureRead)
{
reader.BaseStream.Seek(4, SeekOrigin.Current);
}
if (is64bit)
{
compressedSize = reader.ReadInt64();
uncompressedSize = reader.ReadInt64();
}
else
{
compressedSize = reader.ReadInt32();
uncompressedSize = reader.ReadInt32();
}
reader.BaseStream.Seek(-seekSize - entry.CompressedLength - 4, SeekOrigin.Current); // Seek back to the beginning of compressed stream
}
if (entry.CompressedLength != compressedSize)
{
return(false);
}
if (entry.Length != uncompressedSize)
{
return(false);
}
return(true);
}
// should only throw an exception in extremely exceptional cases because it is called from dispose
internal void WriteCentralDirectoryFileHeader()
{
// This part is simple, because we should definitely know the sizes by this time
BinaryWriter writer = new BinaryWriter(_archive.ArchiveStream);
// _entryname only gets set when we read in or call moveTo. MoveTo does a check, and
// reading in should not be able to produce an entryname longer than ushort.MaxValue
Debug.Assert(_storedEntryNameBytes.Length <= ushort.MaxValue);
// decide if we need the Zip64 extra field:
Zip64ExtraField zip64ExtraField = new Zip64ExtraField();
uint compressedSizeTruncated, uncompressedSizeTruncated, offsetOfLocalHeaderTruncated;
bool zip64Needed = false;
if (SizesTooLarge()
#if DEBUG_FORCE_ZIP64
|| _archive._forceZip64
#endif
)
{
zip64Needed = true;
compressedSizeTruncated = ZipHelper.Mask32Bit;
uncompressedSizeTruncated = ZipHelper.Mask32Bit;
// If we have one of the sizes, the other must go in there as speced for LH, but not necessarily for CH, but we do it anyways
zip64ExtraField.CompressedSize = _compressedSize;
zip64ExtraField.UncompressedSize = _uncompressedSize;
}
else
{
compressedSizeTruncated = (uint)_compressedSize;
uncompressedSizeTruncated = (uint)_uncompressedSize;
}
if (_offsetOfLocalHeader > uint.MaxValue
#if DEBUG_FORCE_ZIP64
|| _archive._forceZip64
#endif
)
{
zip64Needed = true;
offsetOfLocalHeaderTruncated = ZipHelper.Mask32Bit;
// If we have one of the sizes, the other must go in there as speced for LH, but not necessarily for CH, but we do it anyways
zip64ExtraField.LocalHeaderOffset = _offsetOfLocalHeader;
}
else
{
offsetOfLocalHeaderTruncated = (uint)_offsetOfLocalHeader;
}
if (zip64Needed)
{
VersionToExtractAtLeast(ZipVersionNeededValues.Zip64);
}
// determine if we can fit zip64 extra field and original extra fields all in
int bigExtraFieldLength = (zip64Needed ? zip64ExtraField.TotalSize : 0)
+ (_cdUnknownExtraFields != null ? ZipGenericExtraField.TotalSize(_cdUnknownExtraFields) : 0);
ushort extraFieldLength;
if (bigExtraFieldLength > ushort.MaxValue)
{
extraFieldLength = (ushort)(zip64Needed ? zip64ExtraField.TotalSize : 0);
_cdUnknownExtraFields = null;
}
else
{
extraFieldLength = (ushort)bigExtraFieldLength;
}
writer.Write(ZipCentralDirectoryFileHeader.SignatureConstant); // Central directory file header signature (4 bytes)
writer.Write((byte)_versionMadeBySpecification); // Version made by Specification (version) (1 byte)
writer.Write((byte)CurrentZipPlatform); // Version made by Compatibility (type) (1 byte)
writer.Write((ushort)_versionToExtract); // Minimum version needed to extract (2 bytes)
writer.Write((ushort)_generalPurposeBitFlag); // General Purpose bit flag (2 bytes)
writer.Write((ushort)CompressionMethod); // The Compression method (2 bytes)
writer.Write(ZipHelper.DateTimeToDosTime(_lastModified.DateTime)); // File last modification time and date (4 bytes)
writer.Write(_crc32); // CRC-32 (4 bytes)
writer.Write(compressedSizeTruncated); // Compressed Size (4 bytes)
writer.Write(uncompressedSizeTruncated); // Uncompressed Size (4 bytes)
writer.Write((ushort)_storedEntryNameBytes.Length); // File Name Length (2 bytes)
writer.Write(extraFieldLength); // Extra Field Length (2 bytes)
// This should hold because of how we read it originally in ZipCentralDirectoryFileHeader:
Debug.Assert((_fileComment == null) || (_fileComment.Length <= ushort.MaxValue));
writer.Write(_fileComment != null ? (ushort)_fileComment.Length : (ushort)0); // file comment length
writer.Write((ushort)0); // disk number start
writer.Write((ushort)0); // internal file attributes
writer.Write(_externalFileAttr); // external file attributes
writer.Write(offsetOfLocalHeaderTruncated); // offset of local header
writer.Write(_storedEntryNameBytes);
// write extra fields
if (zip64Needed)
{
zip64ExtraField.WriteBlock(_archive.ArchiveStream);
}
if (_cdUnknownExtraFields != null)
{
ZipGenericExtraField.WriteAllBlocks(_cdUnknownExtraFields, _archive.ArchiveStream);
}
if (_fileComment != null)
{
writer.Write(_fileComment);
}
}
private static bool TryGetZip64BlockFromGenericExtraField(ZipGenericExtraField extraField,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber,
out Zip64ExtraField zip64Block)
{
zip64Block = default;
zip64Block._compressedSize = null;
zip64Block._uncompressedSize = null;
zip64Block._localHeaderOffset = null;
zip64Block._startDiskNumber = null;
if (extraField.Tag != TagConstant)
{
return(false);
}
zip64Block._size = extraField.Size;
using (MemoryStream ms = new MemoryStream(extraField.Data))
using (BinaryReader reader = new BinaryReader(ms))
{
// The spec section 4.5.3:
// The order of the fields in the zip64 extended
// information record is fixed, but the fields MUST
// only appear if the corresponding Local or Central
// directory record field is set to 0xFFFF or 0xFFFFFFFF.
// However tools commonly write the fields anyway; the prevailing convention
// is to respect the size, but only actually use the values if their 32 bit
// values were all 0xFF.
if (extraField.Size < sizeof(long))
{
return(true);
}
long value64 = reader.ReadInt64();
if (readUncompressedSize)
{
zip64Block._uncompressedSize = value64;
}
if (ms.Position > extraField.Size - sizeof(long))
{
return(true);
}
value64 = reader.ReadInt64();
if (readCompressedSize)
{
zip64Block._compressedSize = value64;
}
if (ms.Position > extraField.Size - sizeof(long))
{
return(true);
}
value64 = reader.ReadInt64();
if (readLocalHeaderOffset)
{
zip64Block._localHeaderOffset = value64;
}
if (ms.Position > extraField.Size - sizeof(int))
{
return(true);
}
int value32 = reader.ReadInt32();
if (readStartDiskNumber)
{
zip64Block._startDiskNumber = value32;
}
// original values are unsigned, so implies value is too big to fit in signed integer
if (zip64Block._uncompressedSize < 0)
{
throw new InvalidDataException(SR.FieldTooBigUncompressedSize);
}
if (zip64Block._compressedSize < 0)
{
throw new InvalidDataException(SR.FieldTooBigCompressedSize);
}
if (zip64Block._localHeaderOffset < 0)
{
throw new InvalidDataException(SR.FieldTooBigLocalHeaderOffset);
}
if (zip64Block._startDiskNumber < 0)
{
throw new InvalidDataException(SR.FieldTooBigStartDiskNumber);
}
return(true);
}
}
private static bool TryGetZip64BlockFromGenericExtraField(ZipGenericExtraField extraField,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber,
out Zip64ExtraField zip64Block)
{
zip64Block = new Zip64ExtraField();
zip64Block._compressedSize = null;
zip64Block._uncompressedSize = null;
zip64Block._localHeaderOffset = null;
zip64Block._startDiskNumber = null;
if (extraField.Tag != TagConstant)
return false;
//this pattern needed because nested using blocks trigger CA2202
MemoryStream ms = null;
try
{
ms = new MemoryStream(extraField.Data);
using (BinaryReader reader = new BinaryReader(ms))
{
ms = null;
zip64Block._size = extraField.Size;
ushort expectedSize = 0;
if (readUncompressedSize) expectedSize += 8;
if (readCompressedSize) expectedSize += 8;
if (readLocalHeaderOffset) expectedSize += 8;
if (readStartDiskNumber) expectedSize += 4;
//if it is not the expected size, perhaps there is another extra field that matches
if (expectedSize != zip64Block._size)
return false;
if (readUncompressedSize) zip64Block._uncompressedSize = reader.ReadInt64();
if (readCompressedSize) zip64Block._compressedSize = reader.ReadInt64();
if (readLocalHeaderOffset) zip64Block._localHeaderOffset = reader.ReadInt64();
if (readStartDiskNumber) zip64Block._startDiskNumber = reader.ReadInt32();
//original values are unsigned, so implies value is too big to fit in signed integer
if (zip64Block._uncompressedSize < 0) throw new InvalidDataException(SR.FieldTooBigUncompressedSize);
if (zip64Block._compressedSize < 0) throw new InvalidDataException(SR.FieldTooBigCompressedSize);
if (zip64Block._localHeaderOffset < 0) throw new InvalidDataException(SR.FieldTooBigLocalHeaderOffset);
if (zip64Block._startDiskNumber < 0) throw new InvalidDataException(SR.FieldTooBigStartDiskNumber);
return true;
}
}
finally
{
if (ms != null)
ms.Dispose();
}
}
public static Zip64ExtraField GetAndRemoveZip64Block(List<ZipGenericExtraField> extraFields,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64Field = new Zip64ExtraField();
zip64Field._compressedSize = null;
zip64Field._uncompressedSize = null;
zip64Field._localHeaderOffset = null;
zip64Field._startDiskNumber = null;
List<ZipGenericExtraField> markedForDelete = new List<ZipGenericExtraField>();
bool zip64FieldFound = false;
foreach (ZipGenericExtraField ef in extraFields)
{
if (ef.Tag == TagConstant)
{
markedForDelete.Add(ef);
if (!zip64FieldFound)
{
if (TryGetZip64BlockFromGenericExtraField(ef, readUncompressedSize, readCompressedSize,
readLocalHeaderOffset, readStartDiskNumber, out zip64Field))
{
zip64FieldFound = true;
}
}
}
}
foreach (ZipGenericExtraField ef in markedForDelete)
extraFields.Remove(ef);
return zip64Field;
}
// if saveExtraFieldsAndComments is false, FileComment and ExtraFields will be null
// in either case, the zip64 extra field info will be incorporated into other fields
public static bool TryReadBlock(BinaryReader reader, bool saveExtraFieldsAndComments, out ZipCentralDirectoryFileHeader header)
{
header = new ZipCentralDirectoryFileHeader();
if (reader.ReadUInt32() != SignatureConstant)
{
return(false);
}
header.VersionMadeBySpecification = reader.ReadByte();
header.VersionMadeByCompatibility = reader.ReadByte();
header.VersionNeededToExtract = reader.ReadUInt16();
header.GeneralPurposeBitFlag = reader.ReadUInt16();
header.CompressionMethod = reader.ReadUInt16();
header.LastModified = reader.ReadUInt32();
header.Crc32 = reader.ReadUInt32();
uint compressedSizeSmall = reader.ReadUInt32();
uint uncompressedSizeSmall = reader.ReadUInt32();
header.FilenameLength = reader.ReadUInt16();
header.ExtraFieldLength = reader.ReadUInt16();
header.FileCommentLength = reader.ReadUInt16();
ushort diskNumberStartSmall = reader.ReadUInt16();
header.InternalFileAttributes = reader.ReadUInt16();
header.ExternalFileAttributes = reader.ReadUInt32();
uint relativeOffsetOfLocalHeaderSmall = reader.ReadUInt32();
header.Filename = reader.ReadBytes(header.FilenameLength);
bool uncompressedSizeInZip64 = uncompressedSizeSmall == ZipHelper.Mask32Bit;
bool compressedSizeInZip64 = compressedSizeSmall == ZipHelper.Mask32Bit;
bool relativeOffsetInZip64 = relativeOffsetOfLocalHeaderSmall == ZipHelper.Mask32Bit;
bool diskNumberStartInZip64 = diskNumberStartSmall == ZipHelper.Mask16Bit;
Zip64ExtraField zip64;
long endExtraFields = reader.BaseStream.Position + header.ExtraFieldLength;
using (Stream str = new SubReadStream(reader.BaseStream, reader.BaseStream.Position, header.ExtraFieldLength))
{
if (saveExtraFieldsAndComments)
{
header.ExtraFields = ZipGenericExtraField.ParseExtraField(str);
zip64 = Zip64ExtraField.GetAndRemoveZip64Block(header.ExtraFields,
uncompressedSizeInZip64, compressedSizeInZip64,
relativeOffsetInZip64, diskNumberStartInZip64);
}
else
{
header.ExtraFields = null;
zip64 = Zip64ExtraField.GetJustZip64Block(str,
uncompressedSizeInZip64, compressedSizeInZip64,
relativeOffsetInZip64, diskNumberStartInZip64);
}
}
// There are zip files that have malformed ExtraField blocks in which GetJustZip64Block() silently bails out without reading all the way to the end
// of the ExtraField block. Thus we must force the stream's position to the proper place.
reader.BaseStream.AdvanceToPosition(endExtraFields);
if (saveExtraFieldsAndComments)
{
header.FileComment = reader.ReadBytes(header.FileCommentLength);
}
else
{
reader.BaseStream.Position += header.FileCommentLength;
header.FileComment = null;
}
header.UncompressedSize = zip64.UncompressedSize == null
? uncompressedSizeSmall
: zip64.UncompressedSize.Value;
header.CompressedSize = zip64.CompressedSize == null
? compressedSizeSmall
: zip64.CompressedSize.Value;
header.RelativeOffsetOfLocalHeader = zip64.LocalHeaderOffset == null
? relativeOffsetOfLocalHeaderSmall
: zip64.LocalHeaderOffset.Value;
header.DiskNumberStart = zip64.StartDiskNumber == null
? diskNumberStartSmall
: zip64.StartDiskNumber.Value;
return(true);
}
public static bool TryReadBlock(BinaryReader reader, bool saveExtraFieldsAndComments, out ZipCentralDirectoryFileHeader header)
{
Zip64ExtraField justZip64Block;
long? uncompressedSize;
long value;
long num;
long value1;
header = new ZipCentralDirectoryFileHeader();
if (reader.ReadUInt32() != 33639248)
{
return(false);
}
header.VersionMadeBy = reader.ReadUInt16();
header.VersionNeededToExtract = reader.ReadUInt16();
header.GeneralPurposeBitFlag = reader.ReadUInt16();
header.CompressionMethod = reader.ReadUInt16();
header.LastModified = reader.ReadUInt32();
header.Crc32 = reader.ReadUInt32();
uint num1 = reader.ReadUInt32();
uint num2 = reader.ReadUInt32();
header.FilenameLength = reader.ReadUInt16();
header.ExtraFieldLength = reader.ReadUInt16();
header.FileCommentLength = reader.ReadUInt16();
ushort num3 = reader.ReadUInt16();
header.InternalFileAttributes = reader.ReadUInt16();
header.ExternalFileAttributes = reader.ReadUInt32();
uint num4 = reader.ReadUInt32();
header.Filename = reader.ReadBytes((int)header.FilenameLength);
bool flag = num2 == -1;
bool flag1 = num1 == -1;
bool flag2 = num4 == -1;
bool flag3 = num3 == 65535;
long position = (long)(reader.BaseStream.Position + (ulong)header.ExtraFieldLength);
using (Stream subReadStream = new SubReadStream(reader.BaseStream, reader.BaseStream.Position, (long)header.ExtraFieldLength))
{
if (!saveExtraFieldsAndComments)
{
header.ExtraFields = null;
justZip64Block = Zip64ExtraField.GetJustZip64Block(subReadStream, flag, flag1, flag2, flag3);
}
else
{
header.ExtraFields = ZipGenericExtraField.ParseExtraField(subReadStream);
justZip64Block = Zip64ExtraField.GetAndRemoveZip64Block(header.ExtraFields, flag, flag1, flag2, flag3);
}
}
reader.BaseStream.AdvanceToPosition(position);
if (!saveExtraFieldsAndComments)
{
Stream baseStream = reader.BaseStream;
baseStream.Position = (long)(baseStream.Position + (ulong)header.FileCommentLength);
header.FileComment = null;
}
else
{
header.FileComment = reader.ReadBytes((int)header.FileCommentLength);
}
if (!justZip64Block.UncompressedSize.HasValue)
{
value = (long)((ulong)num2);
}
else
{
uncompressedSize = justZip64Block.UncompressedSize;
value = uncompressedSize.Value;
}
header.UncompressedSize = value;
if (!justZip64Block.CompressedSize.HasValue)
{
num = (long)((ulong)num1);
}
else
{
uncompressedSize = justZip64Block.CompressedSize;
num = uncompressedSize.Value;
}
header.CompressedSize = num;
if (!justZip64Block.LocalHeaderOffset.HasValue)
{
value1 = (long)((ulong)num4);
}
else
{
uncompressedSize = justZip64Block.LocalHeaderOffset;
value1 = uncompressedSize.Value;
}
header.RelativeOffsetOfLocalHeader = value1;
header.DiskNumberStart = (!justZip64Block.StartDiskNumber.HasValue ? (int)num3 : justZip64Block.StartDiskNumber.Value);
return(true);
}