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mirror of https://github.com/OpenDiablo2/OpenDiablo2 synced 2024-11-05 09:47:18 -05:00
OpenDiablo2/OpenDiablo2.Common/Models/MPQ.cs

367 lines
14 KiB
C#

using OpenDiablo2.Common.Enums;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace OpenDiablo2.Common.Models
{
public sealed class MPQ : IDisposable
{
private const string HEADER_SIGNATURE = "MPQ\x1A";
private const string USERDATA_SIGNATURE = "MPQ\x1B";
private const string LISTFILE_NAME = "(listfile)";
private const int MPQ_HASH_FILE_KEY = 3;
private const int MPQ_HASH_TABLE_OFFSET = 0;
private const int MPQ_HASH_NAME_A = 1;
private const int MPQ_HASH_NAME_B = 2;
private const UInt32 MPQ_HASH_ENTRY_EMPTY = 0xFFFFFFFF;
private const UInt32 MPQ_HASH_ENTRY_DELETED = 0xFFFFFFFE;
internal struct HeaderRecord
{
public UInt32 HeaderSize;
public UInt32 ArchiveSize;
public UInt16 FormatVersion;
public Byte BlockSize;
public UInt32 HashTablePos;
public UInt32 BlockTablePos;
public UInt32 HashTableSize;
public UInt32 BlockTableSize;
// Other properties are for >0 MPQ version
}
[Flags]
internal enum eBlockRecordFlags : UInt32
{
IsFile = 0x80000000, // Block is a file, and follows the file data format; otherwise, block is free space or unused. If the block is not a file, all other flags should be cleared, and FileSize should be 0.
SingleUnit = 0x01000000, // File is stored as a single unit, rather than split into sectors.
KeyAdjusted = 0x00020000, // The file's encryption key is adjusted by the block offset and file size (explained in detail in the File Data section). File must be encrypted.
IsEncrypted = 0x00010000, // File is encrypted.
IsCompressed = 0x00000200, // File is compressed. File cannot be imploded.
IsImploded = 0x00000100 // File is imploded. File cannot be compressed.
}
internal struct BlockRecord
{
public UInt32 BlockOffset;
public UInt32 BlockSize;
public UInt32 FileSize;
public UInt32 Flags;
public uint EncryptionSeed { get; set; }
public string FileName { get; internal set; }
public bool IsFile => (Flags & (UInt32)eBlockRecordFlags.IsFile) != 0;
public bool SingleUnit => (Flags & (UInt32)eBlockRecordFlags.SingleUnit) != 0;
public bool KeyAdjusted => (Flags & (UInt32)eBlockRecordFlags.KeyAdjusted) != 0;
public bool IsEncrypted => (Flags & (UInt32)eBlockRecordFlags.IsEncrypted) != 0;
public bool IsCompressed => (Flags & (UInt32)eBlockRecordFlags.IsCompressed) != 0;
public bool IsImploded => (Flags & (UInt32)eBlockRecordFlags.IsImploded) != 0;
}
internal struct HashRecord
{
public UInt32 FilePathHashA;
public UInt32 FilePathHashB;
public UInt16 Language;
public UInt16 Platform;
public UInt32 FileBlockIndex;
}
internal static UInt32[] cryptTable = new UInt32[0x500];
internal HeaderRecord Header;
private List<BlockRecord> blockTable = new List<BlockRecord>();
private List<HashRecord> hashTable = new List<HashRecord>();
internal Stream fileStream;
public UInt16 LanguageId = 0;
public const byte Platform = 0;
public string Path { get; private set; }
public eMPQFormatVersion FormatVersion => (eMPQFormatVersion)Header.FormatVersion;
public List<string> Files => GetFilePaths();
private List<string> GetFilePaths()
{
using (var stream = OpenFile("(listfile)"))
{
if (stream == null)
{
return new List<string>();
}
var sr = new StreamReader(stream);
var text = sr.ReadToEnd();
return text.Split('\n').Where(x => !String.IsNullOrWhiteSpace(x)).Select(x => x.Trim()).ToList();
}
}
static MPQ()
{
InitializeCryptTable();
}
public MPQ(string path)
{
this.Path = path;
fileStream = new FileStream(path, FileMode.Open);
using (var br = new BinaryReader(fileStream, Encoding.Default, true))
{
var header = Encoding.ASCII.GetString(br.ReadBytes(4));
if (header != HEADER_SIGNATURE)
throw new ApplicationException($"Unknown header signature '{header}' detected while processing '{Path}'!");
ParseMPQHeader(br);
}
}
private static void InitializeCryptTable()
{
UInt32 seed = 0x00100001;
UInt32 index1 = 0;
UInt32 index2 = 0;
int i;
for (index1 = 0; index1 < 0x100; index1++)
{
for (index2 = index1, i = 0; i < 5; i++, index2 += 0x100)
{
seed = (seed * 125 + 3) % 0x2AAAAB;
var temp = (seed & 0xFFFF) << 0x10;
seed = (seed * 125 + 3) % 0x2AAAAB;
cryptTable[index2] = (temp | (seed & 0xFFFF));
}
}
}
internal static void DecryptBlock(uint[] data, uint seed1)
{
uint seed2 = 0xeeeeeeee;
for (int i = 0; i < data.Length; i++)
{
seed2 += cryptTable[0x400 + (seed1 & 0xff)];
uint result = data[i];
result ^= seed1 + seed2;
seed1 = ((~seed1 << 21) + 0x11111111) | (seed1 >> 11);
seed2 = result + seed2 + (seed2 << 5) + 3;
data[i] = result;
}
}
internal static void DecryptBlock(byte[] data, uint seed1)
{
uint seed2 = 0xeeeeeeee;
// NB: If the block is not an even multiple of 4,
// the remainder is not encrypted
for (int i = 0; i < data.Length - 3; i += 4)
{
seed2 += cryptTable[(int)(0x400 + (seed1 & 0xff))];
uint result = BitConverter.ToUInt32(data, i);
result ^= (seed1 + seed2);
seed1 = ((~seed1 << 21) + 0x11111111) | (seed1 >> 11);
seed2 = result + seed2 + (seed2 << 5) + 3;
data[i + 0] = ((byte)(result & 0xff));
data[i + 1] = ((byte)((result >> 8) & 0xff));
data[i + 2] = ((byte)((result >> 16) & 0xff));
data[i + 3] = ((byte)((result >> 24) & 0xff));
}
}
private void ParseMPQHeader(BinaryReader br)
{
Header = new HeaderRecord
{
HeaderSize = br.ReadUInt32(),
ArchiveSize = br.ReadUInt32(),
FormatVersion = br.ReadUInt16(),
BlockSize = (byte)br.ReadInt16(),
HashTablePos = br.ReadUInt32(),
BlockTablePos = br.ReadUInt32(),
HashTableSize = br.ReadUInt32(),
BlockTableSize = br.ReadUInt32()
};
if (FormatVersion != eMPQFormatVersion.Format1)
throw new ApplicationException($"Unsupported MPQ format version of {Header.FormatVersion} detected for '{Path}'!");
if (br.BaseStream.Position != Header.HeaderSize)
throw new ApplicationException($"Invalid header size detected for '{Path}'. Expected to be at offset {Header.HeaderSize} but we are at offset {br.BaseStream.Position} instead!");
br.BaseStream.Seek(Header.BlockTablePos, SeekOrigin.Begin);
// Process the block table
var bData = br.ReadBytes((int)(16 * Header.BlockTableSize));
DecryptBlock(bData, HashString("(block table)", MPQ_HASH_FILE_KEY));
using (var ms = new MemoryStream(bData))
using (var dr = new BinaryReader(new MemoryStream(bData)))
for (var index = 0; index < Header.BlockTableSize; index++)
{
blockTable.Add(new BlockRecord
{
BlockOffset = dr.ReadUInt32(),
BlockSize = dr.ReadUInt32(),
FileSize = dr.ReadUInt32(),
Flags = dr.ReadUInt32()
});
}
// Process the hash table
br.BaseStream.Seek(Header.HashTablePos, SeekOrigin.Begin);
bData = br.ReadBytes((int)(16 * Header.HashTableSize));
DecryptBlock(bData, HashString("(hash table)", MPQ_HASH_FILE_KEY));
using (var ms = new MemoryStream(bData))
using (var dr = new BinaryReader(new MemoryStream(bData)))
for (var index = 0; index < Header.HashTableSize; index++)
{
hashTable.Add(new HashRecord
{
FilePathHashA = dr.ReadUInt32(),
FilePathHashB = dr.ReadUInt32(),
Language = dr.ReadUInt16(),
Platform = dr.ReadUInt16(),
FileBlockIndex = dr.ReadUInt32()
});
}
}
private uint CalculateEncryptionSeed(BlockRecord record)
{
if (record.FileName == null) return 0;
uint seed = HashString(System.IO.Path.GetFileName(record.FileName), MPQ_HASH_FILE_KEY);
if (record.KeyAdjusted)
seed = (seed + record.BlockOffset) ^ record.FileSize;
return seed;
}
private static UInt32 HashString(string inputString, UInt32 hashType)
{
if (hashType > MPQ_HASH_FILE_KEY)
throw new ApplicationException($"Unknown hash type {hashType} for input string {inputString}");
UInt32 seed1 = 0x7FED7FED;
UInt32 seed2 = 0xEEEEEEEE;
foreach (var ch in inputString)
{
var chInt = (UInt32)char.ToUpper(ch);
seed1 = cryptTable[(hashType * 0x100) + chInt] ^ (seed1 + seed2);
seed2 = chInt + seed1 + seed2 + (seed2 << 5) + 3;
}
return seed1;
}
private static UInt32 ComputeFileKey(string filePath, BlockRecord blockRecord, UInt32 archiveOffset)
{
var fileName = filePath.Split('\\').Last();
// Hash the name to get the base key
var fileKey = HashString(fileName, MPQ_HASH_FILE_KEY);
// Offset-adjust the key if necessary
if (blockRecord.KeyAdjusted)
fileKey = (fileKey + blockRecord.BlockOffset) ^ blockRecord.FileSize;
return fileKey;
}
private bool FindFileInHashTable(string filePath, out UInt32 fileHashEntry)
{
fileHashEntry = 0;
// Find the home entry in the hash table for the file
UInt32 initEntry = HashString(filePath, MPQ_HASH_TABLE_OFFSET) & (UInt32)(Header.HashTableSize - 1);
// Is there anything there at all?
if (hashTable[(int)initEntry].FileBlockIndex == MPQ_HASH_ENTRY_EMPTY)
return false;
// Compute the hashes to compare the hash table entry against
var nNameHashA = HashString(filePath, MPQ_HASH_NAME_A);
var nNameHashB = HashString(filePath, MPQ_HASH_NAME_B);
var iCurEntry = initEntry;
// Check each entry in the hash table till a termination point is reached
do
{
if (hashTable[(int)iCurEntry].FileBlockIndex != MPQ_HASH_ENTRY_DELETED)
{
if (hashTable[(int)iCurEntry].FilePathHashA == nNameHashA
&& hashTable[(int)iCurEntry].FilePathHashB == nNameHashB
&& hashTable[(int)iCurEntry].Language == LanguageId
&& hashTable[(int)iCurEntry].Platform == (UInt16)PlatformID.Win32S)
{
fileHashEntry = iCurEntry;
return true;
}
}
iCurEntry = (iCurEntry + 1) & (UInt32)(Header.HashTableSize - 1);
} while (iCurEntry != initEntry && hashTable[(int)iCurEntry].FileBlockIndex != MPQ_HASH_ENTRY_EMPTY);
return false;
}
private bool GetHashRecord(string fileName, out HashRecord hash)
{
uint index = HashString(fileName, 0);
index &= Header.HashTableSize - 1;
uint name1 = HashString(fileName, MPQ_HASH_NAME_A);
uint name2 = HashString(fileName, MPQ_HASH_NAME_B);
for (uint i = index; i < hashTable.Count(); ++i)
{
hash = hashTable[(int)i];
if (hash.FilePathHashA == name1 && hash.FilePathHashB == name2)
return true;
}
for (uint i = 0; i < index; i++)
{
hash = hashTable[(int)i];
if (hash.FilePathHashA == name1 && hash.FilePathHashB == name2)
return true;
}
hash = new HashRecord();
return false;
}
public MPQStream OpenFile(string filename)
{
HashRecord hash;
BlockRecord block;
if (!GetHashRecord(filename, out hash))
throw new FileNotFoundException("File not found: " + filename);
block = blockTable[(int)hash.FileBlockIndex];
block.FileName = filename.ToLower();
block.EncryptionSeed = CalculateEncryptionSeed(block);
return new MPQStream(this, block);
}
public void Dispose()
{
fileStream?.Dispose();
}
}
}