2016-10-16 09:22:53 +04:00

454 lines
16 KiB
C#

//! \file ArcDX.cs
//! \date Thu Oct 08 00:18:56 2015
//! \brief DxLib engine archives with 'DX' signature.
//
// Copyright (C) 2015-2016 by morkt
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//
using System;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using System.IO;
using System.Linq;
using GameRes.Utility;
namespace GameRes.Formats.DxLib
{
internal class DxArchive : ArcFile
{
public readonly byte[] Key;
public DxArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, byte[] key)
: base (arc, impl, dir)
{
Key = key;
}
}
[Serializable]
public class DxScheme : ResourceScheme
{
public IList<byte[]> KnownKeys;
}
[Export(typeof(ArchiveFormat))]
public class DxOpener : ArchiveFormat
{
public override string Tag { get { return "DXA"; } }
public override string Description { get { return "DxLib engine resource archive"; } }
public override uint Signature { get { return 0; } }
public override bool IsHierarchic { get { return true; } }
public override bool CanWrite { get { return false; } }
public DxOpener ()
{
Extensions = new string[] { "dxa", "hud", "usi", "med", "dat" };
Signatures = new uint[] { 0x19EF8ED4, 0xA9FCCEDD, 0x0AEE0FD3, 0x5523F211, 0x5524F211, 0 };
}
public static IList<byte[]> KnownKeys = new List<byte[]>();
public override ArcFile TryOpen (ArcView file)
{
if (file.MaxOffset < 0x1C)
return null;
uint signature = file.View.ReadUInt32 (0);
foreach (var key in KnownKeys)
{
uint sig_key = LittleEndian.ToUInt32 (key, 0);
uint sig_test = signature ^ sig_key;
int version = (int)(sig_test >> 16);
if (0x5844 == (sig_test & 0xFFFF) && version <= 4) // 'DX'
{
var dir = ReadIndex (file, version, key);
if (null != dir)
{
if (KnownKeys[0] != key)
{
// move last used key to the top of the known keys list
KnownKeys.Remove (key);
KnownKeys.Insert (0, key);
}
return new DxArchive (file, this, dir, key);
}
return null;
}
}
return GuessKey (file);
}
ArcFile GuessKey (ArcView file)
{
if (file.MaxOffset > uint.MaxValue)
return null;
var key = new byte[12];
for (short version = 4; version >= 1; --version)
{
file.View.Read (0, key, 0, 12);
key[0] ^= (byte)'D';
key[1] ^= (byte)'X';
key[2] ^= (byte)version;
int base_offset = version > 3 ? 0x1C : 0x18;
key[8] ^= (byte)base_offset;
uint key0 = LittleEndian.ToUInt32 (key, 0);
uint index_offset = file.View.ReadUInt32 (12) ^ key0;
if (index_offset <= base_offset || index_offset >= file.MaxOffset)
continue;
uint index_size = (uint)(file.MaxOffset - index_offset);
if (index_size > 0xFFFFFF)
continue;
key[4] ^= (byte)index_size;
key[5] ^= (byte)(index_size >> 8);
key[6] ^= (byte)(index_size >> 16);
try
{
var dir = ReadIndex (file, version, key);
if (null != dir)
{
KnownKeys.Insert (0, key);
return new DxArchive (file, this, dir, key);
}
}
catch { /* ignore parse errors */ }
}
return null;
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
Stream input = arc.File.CreateStream (entry.Offset, entry.Size);
var dx_arc = arc as DxArchive;
if (null == dx_arc)
return input;
input = new EncryptedStream (input, entry.Offset, dx_arc.Key);
var dx_ent = entry as PackedEntry;
if (null == dx_ent || !dx_ent.IsPacked)
return input;
using (input)
{
var data = Unpack (input);
return new BinMemoryStream (data, entry.Name);
}
}
byte[] Unpack (Stream stream)
{
using (var input = new ArcView.Reader (stream))
{
uint unpacked_size = input.ReadUInt32();
int remaining = input.ReadInt32() - 9;
var output = new byte[unpacked_size];
byte control_code = input.ReadByte();
int dst = 0;
while (remaining > 0)
{
byte b = input.ReadByte();
--remaining;
if (b != control_code)
{
output[dst++] = b;
continue;
}
b = input.ReadByte();
--remaining;
if (b == control_code)
{
output[dst++] = b;
continue;
}
if (b > control_code)
--b;
int count = b >> 3;
if (0 != (b & 4))
{
count |= input.ReadByte() << 5;
--remaining;
}
count += 4;
int offset;
switch (b & 3)
{
case 0:
offset = input.ReadByte();
--remaining;
break;
case 1:
offset = input.ReadUInt16();
remaining -= 2;
break;
case 2:
offset = input.ReadUInt16();
offset |= input.ReadByte() << 16;
remaining -= 3;
break;
default:
throw new InvalidFormatException ("DX decompression failed");
}
++offset;
Binary.CopyOverlapped (output, dst - offset, dst, count);
dst += count;
}
return output;
}
}
List<Entry> ReadIndex (ArcView file, int version, byte[] key)
{
var header = file.View.ReadBytes (4, 0x18);
if (0x18 != header.Length)
return null;
Decrypt (header, 0, header.Length, 4, key);
var dx = new DxHeader {
IndexSize = LittleEndian.ToUInt32 (header, 0),
BaseOffset = LittleEndian.ToUInt32 (header, 4),
IndexOffset = LittleEndian.ToUInt32 (header, 8),
FileTable = LittleEndian.ToUInt32 (header, 0x0c),
DirTable = LittleEndian.ToUInt32 (header, 0x10),
};
if (dx.DirTable >= dx.IndexSize || dx.FileTable >= dx.IndexSize)
return null;
using (var encrypted = file.CreateStream (dx.IndexOffset, dx.IndexSize))
using (var index = new EncryptedStream (encrypted, dx.IndexOffset, key))
using (var reader = new IndexReader (dx, version, index))
{
return reader.Read();
}
}
internal static void Decrypt (byte[] data, int index, int count, long offset, byte[] key)
{
int key_pos = (int)(offset % key.Length);
for (int i = 0; i < count; ++i)
{
data[index+i] ^= key[key_pos++];
if (key.Length == key_pos)
key_pos = 0;
}
}
public static byte[] CreateKey (string keyword)
{
byte[] key;
if (string.IsNullOrEmpty (keyword))
{
key = Enumerable.Repeat<byte> (0xAA, 12).ToArray();
}
else
{
key = new byte[12];
int char_count = Math.Min (keyword.Length, 12);
int length = Encodings.cp932.GetBytes (keyword, 0, char_count, key, 0);
if (length < 12)
Binary.CopyOverlapped (key, 0, length, 12-length);
}
key[0] ^= 0xFF;
key[1] = Binary.RotByteR (key[1], 4);
key[2] ^= 0x8A;
key[3] = (byte)~Binary.RotByteR (key[3], 4);
key[4] ^= 0xFF;
key[5] ^= 0xAC;
key[6] ^= 0xFF;
key[7] = (byte)~Binary.RotByteR (key[7], 3);
key[8] = Binary.RotByteL (key[8], 3);
key[9] ^= 0x7F;
key[10] = (byte)(Binary.RotByteR (key[10], 4) ^ 0xD6);
key[11] ^= 0xCC;
return key;
}
public override ResourceScheme Scheme
{
get { return new DxScheme { KnownKeys = KnownKeys }; }
set { KnownKeys = ((DxScheme)value).KnownKeys; }
}
}
internal class DxHeader
{
public long BaseOffset;
public long IndexOffset;
public uint IndexSize;
public uint FileTable;
public uint DirTable;
}
internal class DxDirectory
{
public int DirOffset;
public int ParentDirOffset;
public int FileCount;
public int FileTable;
}
internal sealed class IndexReader : IDisposable
{
readonly int m_version;
readonly int m_entry_size;
DxHeader m_header;
BinaryReader m_input;
List<Entry> m_dir = new List<Entry>();
public List<Entry> Dir { get { return m_dir; } }
public IndexReader (DxHeader header, int version, Stream input)
{
m_version = version;
m_entry_size = m_version >= 2 ? 0x2C : 0x28;
m_header = header;
m_input = new ArcView.Reader (input);
}
public List<Entry> Read ()
{
ReadFileTable ("", 0);
return m_dir;
}
DxDirectory ReadDirEntry ()
{
var dir = new DxDirectory();
dir.DirOffset = m_input.ReadInt32();
dir.ParentDirOffset = m_input.ReadInt32();
dir.FileCount = m_input.ReadInt32();
dir.FileTable = m_input.ReadInt32();
return dir;
}
void ReadFileTable (string root, uint table_offset)
{
m_input.BaseStream.Position = m_header.DirTable + table_offset;
var dir = ReadDirEntry();
if (dir.DirOffset != -1 && dir.ParentDirOffset != -1)
{
m_input.BaseStream.Position = m_header.FileTable + dir.DirOffset;
root = Path.Combine (root, ExtractFileName (m_input.ReadUInt32()));
}
long current_pos = m_header.FileTable + dir.FileTable;
for (int i = 0; i < dir.FileCount; ++i)
{
m_input.BaseStream.Position = current_pos;
uint name_offset = m_input.ReadUInt32();
uint attr = m_input.ReadUInt32();
m_input.BaseStream.Seek (0x18, SeekOrigin.Current);
uint offset = m_input.ReadUInt32();
if (0 != (attr & 0x10)) // FILE_ATTRIBUTE_DIRECTORY
{
if (0 == offset || table_offset == offset)
throw new InvalidFormatException ("Infinite recursion in DXA directory index");
ReadFileTable (root, offset);
}
else
{
uint size = m_input.ReadUInt32();
int packed_size = -1;
if (m_version >= 2)
packed_size = m_input.ReadInt32();
var entry = FormatCatalog.Instance.Create<PackedEntry> (Path.Combine (root, ExtractFileName (name_offset)));
entry.Offset = m_header.BaseOffset + offset;
entry.UnpackedSize = size;
entry.IsPacked = -1 != packed_size;
if (entry.IsPacked)
entry.Size = (uint)packed_size;
else
entry.Size = size;
m_dir.Add (entry);
}
current_pos += m_entry_size;
}
}
string ExtractFileName (uint table_offset)
{
m_input.BaseStream.Position = table_offset;
int name_offset = m_input.ReadUInt16() * 4 + 4;
m_input.BaseStream.Position = table_offset + name_offset;
return m_input.BaseStream.ReadCString();
}
#region IDisposable Members
bool disposed = false;
public void Dispose ()
{
if (!disposed)
{
m_input.Dispose();
disposed = true;
}
}
#endregion
}
internal class EncryptedStream : ProxyStream
{
private int m_base_pos;
private byte[] m_key;
public EncryptedStream (Stream stream, long base_position, byte[] key, bool leave_open = false)
: base (stream, leave_open)
{
m_key = key;
m_base_pos = (int)(base_position % m_key.Length);
}
public override int Read (byte[] buffer, int offset, int count)
{
var key_pos = m_base_pos + Position;
int read = BaseStream.Read (buffer, offset, count);
if (read > 0)
DxOpener.Decrypt (buffer, offset, count, key_pos, m_key);
return read;
}
public override int ReadByte ()
{
int key_pos = (int)((m_base_pos + Position) % m_key.Length);
int b = BaseStream.ReadByte();
if (-1 != b)
{
b ^= m_key[key_pos];
}
return b;
}
public override void Write (byte[] buffer, int offset, int count)
{
int key_pos = (int)((m_base_pos + Position) % m_key.Length);
byte[] write_buf = new byte[count];
for (int i = 0; i < count; ++i)
{
write_buf[i] = (byte)(buffer[offset+i] ^ m_key[key_pos++]);
if (m_key.Length == key_pos)
key_pos = 0;
}
BaseStream.Write (write_buf, 0, count);
}
public override void WriteByte (byte value)
{
int key_pos = (int)((m_base_pos + Position) % m_key.Length);
BaseStream.WriteByte ((byte)(value ^ m_key[key_pos]));
}
}
}