SabreTools/SabreTools.Serialization
1
0
Fork 0
mirror of https://github.com/SabreTools/SabreTools.Serialization.git synced 2026-09-21 22:35:06 +00:00
Code Issues 56 Packages Projects Releases 20 Wiki Activity

Be more strictly correct about ZIP64 reading

Browse Source
This commit is contained in:
Matt Nadareski
2025-08-27 17:54:35 -04:00
parent 63f5566e65
commit dfbdce1dc8
1 changed files with 92 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files

130
SabreTools.Serialization/Deserializers/PKZIP.cs
View File

@@ -35,9 +35,6 @@ namespace SabreTools.Serialization.Deserializers
var zip64DataDescriptors = new List<DataDescriptor64>();
var cdrs = new List<CentralDirectoryFileHeader>();
// Flag if we have a ZIP64 archive
bool? zip64 = null;
// Read all blocks
do
{
@@ -64,7 +61,6 @@ namespace SabreTools.Serialization.Deserializers
// Local File
case LocalFileHeaderSignature:
if (!ParseLocalFile(data,
ref zip64,
out LocalFileHeader? localFileHeader,
out byte[]? encryptionHeader,
out byte[]? fileDatum,
@@ -106,7 +102,6 @@ namespace SabreTools.Serialization.Deserializers
return null;
// Assign the ZIP64 end of central directory record
zip64 = true;
validBlock = true;
archive.ZIP64EndOfCentralDirectoryRecord = eocdr64;
break;
@@ -118,7 +113,6 @@ namespace SabreTools.Serialization.Deserializers
return null;
// Assign the ZIP64 end of central directory record
zip64 = true;
validBlock = true;
archive.ZIP64EndOfCentralDirectoryLocator = eocdl64;
break;
@@ -265,10 +259,31 @@ namespace SabreTools.Serialization.Deserializers
{
var obj = new DataDescriptor();
// Signatures are expected but not required
obj.Signature = data.ReadUInt32LittleEndian();
if (obj.Signature != DataDescriptorSignature)
data.Seek(-4, SeekOrigin.Current);
// Cache the current position
long currentPosition = data.Position;
// Check if the block is a 12- or 16-byte
bool isShort = false;
if (data.Position + 12 == data.Length)
{
isShort = true;
}
else
{
data.Seek(12, SeekOrigin.Current);
byte[] nextBlock = data.ReadBytes(2);
data.Seek(currentPosition, SeekOrigin.Begin);
if (nextBlock.EqualsExactly([0x50, 0x4B]))
isShort = true;
}
// If the 16-byte variant
if (!isShort)
{
obj.Signature = data.ReadUInt32LittleEndian();
if (obj.Signature != DataDescriptorSignature)
return null;
}
obj.CRC32 = data.ReadUInt32LittleEndian();
obj.CompressedSize = data.ReadUInt32LittleEndian();
@@ -286,10 +301,31 @@ namespace SabreTools.Serialization.Deserializers
{
var obj = new DataDescriptor64();
// Signatures are expected but not required
obj.Signature = data.ReadUInt32LittleEndian();
if (obj.Signature != DataDescriptorSignature)
data.Seek(-4, SeekOrigin.Current);
// Cache the current position
long currentPosition = data.Position;
// Check if the block is a 20- or 24-byte
bool isShort = false;
if (data.Position + 20 == data.Length)
{
isShort = true;
}
else
{
data.Seek(20, SeekOrigin.Current);
byte[] nextBlock = data.ReadBytes(2);
data.Seek(currentPosition, SeekOrigin.Begin);
if (nextBlock.EqualsExactly([0x50, 0x4B]))
isShort = true;
}
// If the 24-byte variant
if (!isShort)
{
obj.Signature = data.ReadUInt32LittleEndian();
if (obj.Signature != DataDescriptorSignature)
return null;
}
obj.CRC32 = data.ReadUInt32LittleEndian();
obj.CompressedSize = data.ReadUInt64LittleEndian();
@@ -386,7 +422,6 @@ namespace SabreTools.Serialization.Deserializers
/// <param name="data">Stream to parse</param>
/// <returns>Filled local file on success, null on error</returns>
public static bool ParseLocalFile(Stream data,
ref bool? zip64,
out LocalFileHeader? localFileHeader,
out byte[]? encryptionHeader,
out byte[]? fileData,
@@ -466,30 +501,12 @@ namespace SabreTools.Serialization.Deserializers
return true;
}
if (zip64 == null)
{
if (data.Position + 16 == data.Length)
{
zip64 = false;
}
else if (data.Position + 24 == data.Length)
{
zip64 = true;
}
else
{
long beforeCheck = data.Position;
data.Seek(16, SeekOrigin.Current);
byte[] nextBlock = data.ReadBytes(2);
data.Seek(beforeCheck, SeekOrigin.Begin);
// Determine if the entry is ZIP64
bool zip64 = IsZip64Descriptor(data);
zip64 = !nextBlock.EqualsExactly([0x50, 0x4B]);
}
}
if (zip64 == true)
// Try to parse the correct data descriptor
if (zip64)
{
// Try to parse the data descriptor
dataDescriptor = new DataDescriptor();
dataDescriptor64 = ParseDataDescriptor64(data);
if (dataDescriptor64 == null)
@@ -497,7 +514,6 @@ namespace SabreTools.Serialization.Deserializers
}
else
{
// Try to parse the data descriptor
dataDescriptor = ParseDataDescriptor(data);
dataDescriptor64 = new DataDescriptor64();
if (dataDescriptor == null)
@@ -552,5 +568,43 @@ namespace SabreTools.Serialization.Deserializers
return obj;
}
/// <summary>
/// Determine if a data descriptor is 64-bit
/// </summary>
/// <param name="data">Stream to parse</param>
/// <returns>True if the descriptor is 64-bit, false otherwise</returns>
private static bool IsZip64Descriptor(Stream data)
{
// Last item in the stream
if (data.Position + 12 == data.Length) // Short 32-bit
return false;
else if (data.Position + 16 == data.Length) // Long 32-bit
return false;
else if (data.Position + 20 == data.Length) // Short 64-bit
return true;
else if (data.Position + 24 == data.Length) // Long 64-bit
return true;
// Cache the current position
long currentPosition = data.Position;
// Short 32-bit
data.Seek(12, SeekOrigin.Current);
byte[] nextBlock = data.ReadBytes(2);
data.Seek(currentPosition, SeekOrigin.Begin);
if (nextBlock.EqualsExactly([0x50, 0x4B]))
return false;
// Long 32-bit
data.Seek(16, SeekOrigin.Current);
nextBlock = data.ReadBytes(2);
data.Seek(currentPosition, SeekOrigin.Begin);
if (nextBlock.EqualsExactly([0x50, 0x4B]))
return false;
// Assume 64-bit otherwise
return true;
}
}
}