2023-08-24 01:33:50 +04:00

777 lines
30 KiB
C#

//! \file ArcCPZ.cs
//! \date Tue Nov 24 11:27:23 2015
//! \brief Purple Software resource archive.
//
// Copyright (C) 2015-2019 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.Formats.Cmvs;
using GameRes.Utility;
namespace GameRes.Formats.Purple
{
[Serializable]
public class CmvsScheme
{
public int Version;
public uint[] Cpz5Secret;
public Cmvs.Md5Variant Md5Variant;
public uint DecoderFactor;
public uint EntryInitKey;
public uint EntrySubKey = 0x5C29E87B;
public byte EntryTailKey;
public byte EntryKeyPos = 9;
public uint IndexSeed = 0x2A65CB4E;
public uint IndexAddend = 0x784C5962;
public uint IndexSubtrahend = 0x79;
public uint[] DirKeyAddend = DefaultDirKeyAddend;
static readonly uint[] DefaultDirKeyAddend = { 0, 0x00112233, 0, 0x34258765 };
}
internal class CpzEntry : Entry
{
public uint CheckSum;
public uint Key;
}
internal class CpzArchive : ArcFile
{
public CpzHeader Header;
public Cpz5Decoder Decoder;
public ArchiveKey Key;
public CpzArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, CpzHeader header, Cpz5Decoder decoder, ArchiveKey key)
: base (arc, impl, dir)
{
Header = header;
Decoder = decoder;
Key = key;
}
}
[Serializable]
public class CpzScheme : ResourceScheme
{
public Dictionary<string, CmvsScheme> KnownSchemes;
}
[Export(typeof(ArchiveFormat))]
public class CpzOpener : ArchiveFormat
{
public override string Tag { get { return "CPZ"; } }
public override string Description { get { return "CMVS engine resource archive"; } }
public override uint Signature { get { return 0x355A5043; } } // 'CPZ5'
public override bool IsHierarchic { get { return true; } }
public override bool CanWrite { get { return false; } }
public CpzOpener ()
{
Signatures = new uint[] { 0x355A5043, 0x365A5043, 0x375A5043 };
}
static CpzScheme DefaultScheme = new CpzScheme();
internal Dictionary<string, CmvsScheme> KnownSchemes { get { return DefaultScheme.KnownSchemes; } }
public override ResourceScheme Scheme
{
get { return DefaultScheme; }
set { DefaultScheme = (CpzScheme)value; }
}
public override ArcFile TryOpen (ArcView file)
{
if (null == KnownSchemes)
throw new OperationCanceledException ("Outdated encryption schemes database");
var cpz = CpzHeader.Parse (file);
if (null == cpz)
return null;
var index = file.View.ReadBytes (cpz.IndexOffset, cpz.IndexSize);
if (!cpz.VerifyIndex (index))
return null;
int file_table_size = cpz.DirEntriesSize + cpz.FileEntriesSize;
if (cpz.IndexKeySize > 24)
{
var index_key = UnpackIndexKey (index, file_table_size, cpz.IndexKeySize);
for (int i = 0; i < file_table_size; ++i)
{
index[i] ^= index_key[(i + 3) % 0x3FF];
}
}
ArchiveKey arc_key = null;
if (cpz.Version > 6)
arc_key = FindArchiveKey (file.Name);
if (null == arc_key)
arc_key = new ArchiveKey();
var index_copy = new CowArray<byte> (index, 0, file_table_size).ToArray();
var cmvs_md5 = cpz.CmvsMd5.Clone() as uint[];
var scheme = CreateCpz5Scheme(Md5Variant.Mirai);
// foreach (var scheme in KnownSchemes.Values.Where (s => s.Version == cpz.Version))
{
var arc = ReadIndex (file, scheme, cpz, index, arc_key);
if (null != arc)
return arc;
// both CmvsMd5 and index was altered by ReadIndex in decryption attempt
Array.Copy (cmvs_md5, cpz.CmvsMd5, 4);
Array.Copy (index_copy, index, file_table_size);
}
throw new UnknownEncryptionScheme();
}
static uint[] DefaultCpz5Secret = {
0xCD90F089, 0xE982B782, 0xA282AB88, 0xCD82718E, 0x52838A83, 0xA882AA82, 0x7592648E, 0xB582AB82,
0xE182BF82, 0xDC82A282, 0x4281B782, 0xED82F48E, 0xBF82EA82, 0xA282E182, 0xB782DC82, 0x6081E682,
0xC6824181, 0xA482A282, 0xE082A982, 0xF48EA482, 0xBF82C182, 0xA282E182, 0xB582DC82, 0xF481BD82,
};
static CmvsScheme CreateCpz5Scheme(Md5Variant md5)
{
return new CmvsScheme
{
Version = 5,
Cpz5Secret = DefaultCpz5Secret,
Md5Variant = md5,
DecoderFactor = 0x1A743125,
EntryInitKey = 0x2547A39E,
EntryTailKey = 0xBC,
};
}
internal ArcFile ReadIndex (ArcView file, CmvsScheme scheme, CpzHeader cpz, byte[] index, ArchiveKey arc_key)
{
var cmvs_md5 = Cmvs.MD5.Create (scheme.Md5Variant);
cmvs_md5.Compute (cpz.CmvsMd5);
DecryptIndexStage1 (index, cpz.MasterKey ^ 0x3795B39A, scheme);
var decoder = new Cpz5Decoder (scheme, cpz.MasterKey, cpz.CmvsMd5[1]);
decoder.Decode (index, 0, cpz.DirEntriesSize, 0x3A);
var key = new uint[4];
key[0] = cpz.CmvsMd5[0] ^ (cpz.MasterKey + 0x76A3BF29);
key[1] = cpz.CmvsMd5[1] ^ cpz.MasterKey;
key[2] = cpz.CmvsMd5[2] ^ (cpz.MasterKey + 0x10000000);
key[3] = cpz.CmvsMd5[3] ^ cpz.MasterKey;
DecryptIndexDirectory (index, cpz.DirEntriesSize, key, arc_key.IndexDirKey);
decoder.Init (cpz.MasterKey, cpz.CmvsMd5[2]);
uint base_offset = cpz.IndexOffset + cpz.IndexSize;
int dir_offset = 0;
var dir = new List<Entry>();
for (int i = 0; i < cpz.DirCount; ++i)
{
int dir_size = LittleEndian.ToInt32 (index, dir_offset);
if (dir_size <= 0x10 || dir_size > index.Length)
return null;
int file_count = LittleEndian.ToInt32 (index, dir_offset+4);
if (file_count >= 0x10000)
return null;
int entries_offset = LittleEndian.ToInt32 (index, dir_offset+8);
uint dir_key = LittleEndian.ToUInt32 (index, dir_offset+0xC);
var dir_name = Binary.GetCString (index, dir_offset+0x10, dir_size-0x10);
int next_entries_offset;
if (i + 1 == cpz.DirCount)
next_entries_offset = cpz.FileEntriesSize;
else
next_entries_offset = LittleEndian.ToInt32 (index, dir_offset + dir_size + 8);
int cur_entries_size = next_entries_offset - entries_offset;
if (cur_entries_size <= 0)
return null;
int cur_offset = cpz.DirEntriesSize + entries_offset;
int cur_entries_end = cur_offset + cur_entries_size;
decoder.Decode (index, cur_offset, cur_entries_size, 0x7E);
for (int j = 0; j < 4; ++j)
key[j] = cpz.CmvsMd5[j] ^ (dir_key + scheme.DirKeyAddend[j]);
DecryptIndexEntry (index, cur_offset, cur_entries_size, key, scheme.IndexSeed, arc_key.IndexEntryKey);
bool is_root_dir = dir_name == "root";
dir.Capacity = dir.Count + file_count;
for (int j = 0; j < file_count; ++j)
{
int entry_size = LittleEndian.ToInt32 (index, cur_offset);
if (entry_size > index.Length || entry_size <= cpz.EntryNameOffset)
return null;
int name_offset = cur_offset + cpz.EntryNameOffset;
var name = Binary.GetCString (index, name_offset, cur_entries_end - name_offset);
if (!is_root_dir)
name = Path.Combine (dir_name, name);
var entry = FormatCatalog.Instance.Create<CpzEntry> (name);
entry.Offset = LittleEndian.ToInt64 (index, cur_offset+4) + base_offset;
entry.Size = LittleEndian.ToUInt32 (index, cur_offset+0xC);
int key_offset = cur_offset + 0x10;
if (cpz.IsLongSize)
key_offset += 4;
entry.CheckSum = LittleEndian.ToUInt32 (index, key_offset);
entry.Key = LittleEndian.ToUInt32 (index, key_offset+4) + dir_key;
if (!entry.CheckPlacement (file.MaxOffset))
return null;
dir.Add (entry);
cur_offset += entry_size;
}
dir_offset += dir_size;
}
if (cpz.IsEncrypted)
decoder.Init (cpz.CmvsMd5[3], cpz.MasterKey);
return new CpzArchive (file, this, dir, cpz, decoder, arc_key);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var carc = arc as CpzArchive;
var cent = entry as CpzEntry;
if (null == carc || null == cent)
return base.OpenEntry (arc, entry);
var data = carc.File.View.ReadBytes (entry.Offset, entry.Size);
if (carc.Header.IsEncrypted)
{
uint key = (carc.Header.MasterKey ^ cent.Key) + (uint)carc.Header.DirCount;
key ^= carc.Key.EntryDataKey2;
key -= carc.Decoder.Scheme.EntrySubKey;
key ^= carc.Header.EntryKey + carc.Key.EntryDataKey1;
carc.Decoder.DecryptEntry (data, carc.Header.CmvsMd5, key);
}
if (data.Length > 0x30 && Binary.AsciiEqual (data, 0, "PS2A"))
data = UnpackPs2 (data);
else if (data.Length > 0x40 && Binary.AsciiEqual (data, 0, "PB3B"))
DecryptPb3 (data);
return new BinMemoryStream (data, entry.Name);
}
internal byte[] UnpackIndexKey (byte[] data, int offset, int length)
{
int key_offset = offset + 20;
int packed_offset = offset + 24;
int packed_length = length - 24;
for (int i = 0; i < packed_length; ++i)
{
data[packed_offset + i] ^= data[key_offset + (i & 3)];
}
int unpacked_length = data.ToInt32 (offset + 16);
var output = new byte[unpacked_length];
var decoder = new HuffmanDecoder (data, packed_offset, packed_length, output);
return decoder.Unpack();
}
void DecryptIndexStage1 (byte[] data, uint key, CmvsScheme scheme)
{
var secret = scheme.Cpz5Secret;
var secret_key = new uint[24];
int secret_length = Math.Min (24, secret.Length);
for (int i = 0; i < secret_length; ++i)
secret_key[i] = secret[i] - key;
int shift = (int)(((key >> 24) ^ (key >> 16) ^ (key >> 8) ^ key ^ 0xB) & 0xF) + 7;
unsafe
{
fixed (byte* raw = data)
{
uint* data32 = (uint*)raw;
int i = 5;
for (int n = data.Length / 4; n > 0; --n)
{
*data32 = Binary.RotR ((secret_key[i] ^ *data32) + scheme.IndexAddend, shift) + 0x01010101;
++data32;
i = (i + 1) % 24;
}
byte* data8 = (byte*)data32;
for (int n = data.Length & 3; n > 0; --n)
{
*data8 = (byte)((*data8 ^ (secret_key[i] >> (n * 4))) - scheme.IndexSubtrahend);
++data8;
i = (i + 1) % 24;
}
}
}
}
void EncryptIndexStage1 (byte[] data, uint key, CmvsScheme scheme)
{
var secret = scheme.Cpz5Secret;
var secret_key = new uint[24];
int secret_length = Math.Min(24, secret.Length);
for (int i = 0; i < secret_length; ++i)
secret_key[i] = secret[i] - key;
int shift = (int)(((key >> 24) ^ (key >> 16) ^ (key >> 8) ^ key ^ 0xB) & 0xF) + 7;
unsafe
{
fixed (byte* raw = data)
{
uint* data32 = (uint*)raw;
int i = 5;
for (int n = data.Length / 4; n > 0; --n)
{
*data32 = (Binary.RotL((*data32 - 0x01010101), shift) - scheme.IndexAddend) ^ secret_key[i];
++data32;
i = (i + 1) % 24;
}
byte* data8 = (byte*)data32;
for (int n = data.Length & 3; n > 0; --n)
{
*data8 = (byte)((*data8 + scheme.IndexSubtrahend) ^ (secret_key[i] >> (n * 4)));
++data8;
i = (i + 1) % 24;
}
}
}
}
void DecryptIndexDirectory (byte[] data, int length, uint[] key, uint arc_key)
{
uint seed = 0x76548AEF;
unsafe
{
fixed (byte* raw = data)
{
uint* data32 = (uint*)raw;
int i;
for (i = 0; i < length / 4; ++i)
{
*data32 = Binary.RotL ((*data32 ^ key[i & 3]) - 0x4A91C262, 3) - seed;
++data32;
seed += 0x10FB562Au ^ arc_key;
}
byte* data8 = (byte*)data32;
for (int j = length & 3; j > 0; --j)
{
*data8 = (byte)((*data8 ^ (key[i++ & 3] >> 6)) + 0x37);
++data8;
}
}
}
}
void EncryptIndexDirectory (byte[] data, int length, uint[] key)
{
uint seed = 0x76548AEF;
unsafe
{
fixed (byte* raw = data)
{
uint* data32 = (uint*)raw;
int i;
for (i = 0; i < length / 4; ++i)
{
*data32 = (Binary.RotR(*data32 + seed, 3) + 0x4A91C262) ^ key[i & 3];
++data32;
seed += 0x10FB562A;
}
byte* data8 = (byte*)data32;
for (int j = length & 3; j > 0; --j)
{
*data8 = (byte)((*data8 - 0x37) ^ (key[i++ & 3] >> 6));
++data8;
}
}
}
}
void DecryptIndexEntry (byte[] data, int offset, int length, uint[] key, uint seed, uint arc_key)
{
if (offset < 0 || offset > data.Length)
throw new ArgumentOutOfRangeException ("offset");
if (length < 0 || length > data.Length || length > data.Length-offset)
throw new ArgumentException ("length");
unsafe
{
fixed (byte* raw = &data[offset])
{
uint* data32 = (uint*)raw;
int i;
for (i = 0; i < length / 4; ++i)
{
*data32 = Binary.RotL ((*data32 ^ key[i & 3]) - seed, 2) + 0x37A19E8B;
++data32;
seed -= 0x139FA9B ^ arc_key;
}
byte* data8 = (byte*)data32;
for (int j = length & 3; j > 0; --j)
{
*data8 = (byte)((*data8 ^ (key[i++ & 3] >> 4)) + 5);
++data8;
}
}
}
}
void EncryptIndexEntry (byte[] data, int offset, int length, uint[] key, uint seed)
{
if (offset < 0 || offset > data.Length)
throw new ArgumentOutOfRangeException("offset");
if (length < 0 || length > data.Length || length > data.Length - offset)
throw new ArgumentException("length");
unsafe
{
fixed (byte* raw = &data[offset])
{
uint* data32 = (uint*)raw;
int i;
for (i = 0; i < length / 4; ++i)
{
*data32 = (Binary.RotR((*data32 - 0x37A19E8B), 2) + seed) ^ key[i & 3];
++data32;
seed -= 0x139FA9B;
}
byte* data8 = (byte*)data32;
for (int j = length & 3; j > 0; --j)
{
*data8 = (byte)((*data8 - 5) ^ (key[i++ & 3] >> 4));
++data8;
}
}
}
}
byte[] UnpackPs2 (byte[] data)
{
DecryptPs2 (data);
return UnpackLzss (data);
}
internal static byte[] UnpackLzss (byte[] data)
{
byte[] frame = new byte[0x800];
int frame_pos = 0x7DF;
int unpacked_size = LittleEndian.ToInt32 (data, 0x28);
byte[] output = new byte[0x30+unpacked_size];
Buffer.BlockCopy (data, 0, output, 0, 0x30);
int src = 0x30;
int dst = 0x30;
int ctl = 1;
while (dst < output.Length && src < data.Length)
{
if (1 == ctl)
ctl = data[src++] | 0x100;
if (0 != (ctl & 1))
{
byte b = data[src++];
output[dst++] = b;
frame[frame_pos++] = b;
frame_pos &= 0x7FF;
}
else
{
int lo = data[src++];
int hi = data[src++];
int offset = lo | (hi & 0xE0) << 3;
int count = (hi & 0x1F) + 2;
for (int i = 0; i < count; ++i)
{
byte b = frame[(offset + i) & 0x7FF];
output[dst++] = b;
frame[frame_pos++] = b;
frame_pos &= 0x7FF;
}
}
ctl >>= 1;
}
return output;
}
void DecryptPs2 (byte[] data)
{
uint key = LittleEndian.ToUInt32 (data, 12);
int shift = (int)(key >> 20) % 5 + 1;
key = (key >> 24) + (key >> 3);
for (int i = 0x30; i < data.Length; ++i)
{
data[i] = Binary.RotByteR ((byte)(key ^ (data[i] - 0x7Cu)), shift);
}
}
void DecryptPb3 (byte[] data)
{
byte key1 = data[data.Length-3];
byte key2 = data[data.Length-2];
int src = data.Length - 0x2F;
for (int i = 8; i < 0x34; i += 2)
{
data[i ] ^= key1;
data[i ] -= data[src++];
data[i+1] ^= key2;
data[i+1] -= data[src++];
}
}
void EncryptPb3 (byte[] data)
{
byte key1 = data[data.Length - 3];
byte key2 = data[data.Length - 2];
int src = data.Length - 0x2F;
for (int i = 8; i < 0x34; i += 2)
{
data[i] += data[src++];
data[i] ^= key1;
data[i + 1] += data[src++];
data[i + 1] ^= key2;
}
}
ArchiveKey FindArchiveKey (string arc_name)
{
// look for "start.ps3" in the same directory as an archive
var start_name = VFS.ChangeFileName (arc_name, "start.ps3");
if (!VFS.FileExists (start_name))
return null;
byte[] start_data;
using (var start = VFS.OpenView (start_name))
{
if (!start.View.AsciiEqual (0, "PS2A"))
return null;
start_data = start.View.ReadBytes (0, (uint)start.MaxOffset);
}
arc_name = Path.GetFileName (arc_name);
start_data = UnpackPs2 (start_data);
int table_count = start_data.ToInt32 (0x10);
int strings_offset = 0x30 + table_count * 4 + start_data.ToInt32 (0x14);
int strings_size = start_data.ToInt32 (0x1C);
if (strings_offset < 0x30 || strings_offset + strings_size > start_data.Length)
return null;
// search strings table for archive name
int string_pos = strings_offset;
int strings_end = strings_offset + strings_size;
int arc_id = -1;
while (string_pos < strings_end)
{
int end_pos = Array.IndexOf<byte> (start_data, 0, string_pos);
if (-1 == end_pos)
end_pos = strings_offset + strings_size;
if (end_pos != string_pos)
{
var text = Encodings.cp932.GetString (start_data, string_pos, end_pos - string_pos);
if (VFS.IsPathEqualsToFileName (text, arc_name))
{
arc_id = string_pos - strings_offset;
break;
}
}
string_pos = end_pos + 1;
}
if (-1 == arc_id)
return null;
// search bytecode for a reference to archive name found above
var id_bytes = new byte[4];
LittleEndian.Pack (arc_id, id_bytes, 0);
for (int data_pos = 0x30 + table_count * 4; data_pos + 4 <= strings_offset; ++data_pos)
{
if (start_data[data_pos+0] == id_bytes[0] && start_data[data_pos+1] == id_bytes[1] &&
start_data[data_pos+2] == id_bytes[2] && start_data[data_pos+3] == id_bytes[3])
{
if (start_data[data_pos-0x33] == 2 && start_data[data_pos-0x32] == 0 &&
start_data[data_pos-0x31] == 1)
{
return new ArchiveKey {
IndexDirKey = start_data.ToUInt32 (data_pos-0x0C),
IndexEntryKey = start_data.ToUInt32 (data_pos-0x18),
EntryDataKey1 = start_data.ToUInt32 (data_pos-0x24),
EntryDataKey2 = start_data.ToUInt32 (data_pos-0x30),
};
}
}
}
return null;
}
}
internal class Cpz5Decoder
{
protected byte[] m_decode_table = new byte[0x100];
protected CmvsScheme m_scheme;
public CmvsScheme Scheme { get { return m_scheme; } }
public Cpz5Decoder (CmvsScheme scheme, uint key, uint summand)
{
m_scheme = scheme;
Init (key, summand);
}
public void Init (uint key, uint summand)
{
for (int i = 0; i < 0x100; ++i)
m_decode_table[i] = (byte)i;
for (int i = 0; i < 0x100; ++i)
{
uint i0 = (key >> 16) & 0xFF;
uint i1 = key & 0xFF;
var tmp = m_decode_table[i0];
m_decode_table[i0] = m_decode_table[i1];
m_decode_table[i1] = tmp;
i0 = (key >> 8) & 0xFF;
i1 = key >> 24;
tmp = m_decode_table[i0];
m_decode_table[i0] = m_decode_table[i1];
m_decode_table[i1] = tmp;
key = summand + m_scheme.DecoderFactor * Binary.RotR (key, 2);
}
}
public void Decode (byte[] data, int offset, int length, byte key)
{
for (int i = 0; i < length; ++i)
data[offset+i] = m_decode_table[key ^ data[offset+i]];
}
public void Encode (byte[] data, int offset, int length, byte key)
{
for (int i = 0; i < length; ++i)
{
for (int s = 0; s < m_decode_table.Length; s++)
{
if (data[offset+i] == m_decode_table[s])
{
data[offset+i] = (byte)(key ^ s);
break;
}
}
}
}
public void DecryptEntry (byte[] data, uint[] cmvs_md5, uint seed)
{
if (null == data)
throw new ArgumentNullException ("data");
if (null == cmvs_md5 || cmvs_md5.Length < 4)
throw new ArgumentException ("cmvs_md5");
int secret_length = Math.Min (m_scheme.Cpz5Secret.Length, 0x10) * sizeof(uint);
byte[] key_bytes = new byte[secret_length];
uint key = cmvs_md5[1] >> 2;
Buffer.BlockCopy (m_scheme.Cpz5Secret, 0, key_bytes, 0, secret_length);
for (int i = 0; i < secret_length; ++i)
key_bytes[i] = (byte)(key ^ m_decode_table[key_bytes[i]]);
uint[] secret_key = new uint[0x10];
Buffer.BlockCopy (key_bytes, 0, secret_key, 0, secret_length);
for (int i = 0; i < secret_key.Length; ++i)
secret_key[i] ^= seed;
unsafe
{
fixed (byte* raw = data)
{
uint* data32 = (uint*)raw;
key = m_scheme.EntryInitKey;
int k = m_scheme.EntryKeyPos;
for (int i = data.Length / 4; i > 0; --i)
{
*data32 = cmvs_md5[key & 3] ^ ((*data32 ^ secret_key[(key >> 6) & 0xf] ^ (secret_key[k] >> 1)) - seed);
k = (k + 1) & 0xf;
key += seed + *data32++;
}
byte* data8 = (byte*)data32;
for (int i = data.Length & 3; i > 0; --i)
{
*data8 = m_decode_table[*data8 ^ m_scheme.EntryTailKey];
++data8;
}
}
}
}
public void EncryptEntry (byte[] data, uint[] cmvs_md5, uint seed)
{
if (null == data)
throw new ArgumentNullException("data");
if (null == cmvs_md5 || cmvs_md5.Length < 4)
throw new ArgumentException("cmvs_md5");
int secret_length = Math.Min(m_scheme.Cpz5Secret.Length, 0x10) * sizeof(uint);
byte[] key_bytes = new byte[secret_length];
uint key = cmvs_md5[1] >> 2;
Buffer.BlockCopy(m_scheme.Cpz5Secret, 0, key_bytes, 0, secret_length);
for (int i = 0; i < secret_length; ++i)
key_bytes[i] = (byte)(key ^ m_decode_table[key_bytes[i]]);
uint[] secret_key = new uint[0x10];
Buffer.BlockCopy(key_bytes, 0, secret_key, 0, secret_length);
for (int i = 0; i < secret_key.Length; ++i)
secret_key[i] ^= seed;
unsafe
{
fixed (byte* raw = data)
{
uint* data32 = (uint*)raw;
key = m_scheme.EntryInitKey;
int k = m_scheme.EntryKeyPos;
for (int i = data.Length / 4; i > 0; --i)
{
uint backup = *data32;
*data32 = (((cmvs_md5[key & 3] ^ *data32) + seed) ^ (secret_key[k] >> 1)) ^ secret_key[(key >> 6) & 0xf];
k = (k + 1) & 0xf;
key += seed + backup;
++data32;
}
byte* data8 = (byte*)data32;
for (int i = data.Length & 3; i > 0; --i)
{
for (int s = 0; s < m_decode_table.Length; s++)
{
if (*data8 == m_decode_table[s])
{
*data8 = (byte)(s ^ m_scheme.EntryTailKey);
break;
}
}
++data8;
}
}
}
}
}
[Serializable]
public class ArchiveKey
{
public uint IndexDirKey;
public uint IndexEntryKey;
public uint EntryDataKey1;
public uint EntryDataKey2;
}
}