2020-03-30 17:38:58 +04:00

276 lines
9.7 KiB
C#

//! \file ArcPCK.cs
//! \date 2020 Mar 29
//! \brief Strikes resource archive.
//
// Copyright (C) 2020 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 GameRes.Compression;
using GameRes.Utility;
namespace GameRes.Formats.Strikes
{
internal class PckEntry : PackedEntry
{
public bool IsEncrypted { get; set; }
}
[Export(typeof(ArchiveFormat))]
public class PckOpener : ArchiveFormat
{
public override string Tag { get { return "PCK/AVG"; } }
public override string Description { get { return "Strikes resource archive"; } }
public override uint Signature { get { return 0; } }
public override bool IsHierarchic { get { return true; } }
public override bool CanWrite { get { return false; } }
public PckOpener ()
{
ContainedFormats = new[] { "LAG", "BMP", "OGG", "WAV", "TXT" };
}
public override ArcFile TryOpen (ArcView file)
{
if (!VFS.IsPathEqualsToFileName (file.Name, "AVGDatas.pck"))
return null;
int seed = Binary.BigEndian (file.View.ReadInt32 (file.MaxOffset - 104));
var header = file.View.ReadBytes (file.MaxOffset - 100, 100);
var rnd = new RandomGenerator();
rnd.Init (seed);
rnd.Decrypt (header, 0, header.Length);
uint checksum = (uint)(header[1] | header[2] << 8 | header[0] << 16 | header[3] << 24) ^ 0xDEFD32D3;
uint length = BigEndian.ToUInt32 (header, 24);
if (checksum != length)
return null;
uint idx_pos = BigEndian.ToUInt32 (header, 28);
uint idx_size = Binary.BigEndian (file.View.ReadUInt32 (idx_pos));
uint index_size;
var index = ReadChunk (file, 8, idx_pos + 4, out index_size);
if (index_size >= 0x80000000)
{
index_size &= 0x7FFFFFFF;
var unpacked = new byte[idx_size];
LzssUnpack (index, index.Length, unpacked);
index = unpacked;
}
using (var input = new BinMemoryStream (index))
{
var dir = new List<Entry>();
int dir_count = 0;
while (input.PeekByte() != -1)
{
input.ReadInt32();
input.ReadInt32();
input.ReadInt32();
int count = Binary.BigEndian (input.ReadInt32());
var dir_name = dir_count.ToString ("X4");
for (int i = 0; i < count; ++i)
{
var name = input.ReadCString (0x28);
name = Path.Combine (dir_name, name);
var entry = Create<PckEntry> (name);
entry.Offset = Binary.BigEndian (input.ReadUInt32());
entry.Size = Binary.BigEndian (input.ReadUInt32());
entry.IsEncrypted = input.ReadInt32() != 0;
entry.UnpackedSize = input.ReadUInt32();
entry.IsPacked = entry.Size != entry.UnpackedSize;
if (!entry.CheckPlacement (file.MaxOffset))
return null;
dir.Add (entry);
}
++dir_count;
}
return new ArcFile (file, this, dir);
}
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var pent = entry as PckEntry;
if (null == pent || !(pent.IsEncrypted || pent.IsPacked))
return base.OpenEntry (arc, entry);
arc.File.View.Reserve (pent.Offset, pent.Size);
int skip_size = 8;
do
{
uint test_size = Binary.BigEndian (arc.File.View.ReadUInt32 (pent.Offset + skip_size * 4));
if (test_size + 4 == pent.Size)
break;
}
while (--skip_size > 0);
byte[] data;
uint data_size = pent.Size;
if (0 == skip_size)
{
data = arc.File.View.ReadBytes (pent.Offset, pent.Size);
}
else
{
data = ReadChunk (arc.File, skip_size, pent.Offset, out data_size);
}
if (pent.IsEncrypted)
{
if (data_size >= 0x10)
DecryptData (data, 0x10, 0xC53A9A6C);
else
DecryptData (data, data.Length, 0x6C9A3AC5);
}
Stream input = new BinMemoryStream (data, pent.Name);
if (pent.IsPacked)
input = new LzssStream (input);
return input;
}
void DecryptData (byte[] data, int length, uint key)
{
for (int i = 0; i < length; ++i)
{
data[i] ^= (byte)(key >> ((i & 3) << 3));
}
}
byte[] ReadChunk (ArcView file, int skipSize, long offset, out uint chunkSize)
{
skipSize *= 4;
var header = file.View.ReadUInt32 (offset);
chunkSize = Binary.BigEndian (file.View.ReadUInt32 (offset + skipSize));
uint size = chunkSize & 0x7FFFFFFF;
var chunk = file.View.ReadBytes (offset + 4, size);
if (skipSize > 0)
{
System.Buffer.BlockCopy (chunk, 0, chunk, 4, skipSize - 4);
LittleEndian.Pack (header, chunk, 0);
}
return chunk;
}
static internal int LzssUnpack (byte[] input, int in_length, byte[] output)
{
var frame = new byte[0x1000];
int frame_pos = 0xFEE;
int src = 0;
int dst = 0;
while (src < in_length)
{
int ctl = input[src++];
for (int bit = 1; bit != 0x100; bit <<= 1)
{
if (0 != (ctl & bit))
{
if (src >= in_length)
return dst;
byte b = input[src++];
frame[frame_pos++ & 0xFFF] = b;
output[dst++] = b;
}
else
{
if (src + 2 > in_length)
return dst;
int lo = input[src++];
int hi = input[src++];
int offset = (hi & 0xF0) << 4 | lo;
int count = Math.Min (3 + (hi & 0xF), output.Length - dst);
while (count --> 0)
{
byte b = frame[offset++ & 0xFFF];
frame[frame_pos++ & 0xFFF] = b;
output[dst++] = b;
}
}
}
}
return dst;
}
}
internal class RandomGenerator
{
int m_count;
int[] m_state = new int[56];
public void Init (int seed)
{
int n = 1;
m_state[55] = seed;
for (int i = 1; i <= 54; ++i)
{
int pos = 21 * i % 55;
m_state[pos] = n;
n = seed - n;
if (n < 0)
n += 1000000000;
seed = m_state[pos];
}
Shuffle();
Shuffle();
Shuffle();
m_count = 55;
}
public uint Rand ()
{
if (++m_count > 55)
{
Shuffle();
m_count = 1;
}
return (uint)m_state[m_count];
}
private void Shuffle ()
{
for (int i = 1; i <= 24; ++i)
{
m_state[i] = m_state[i] - m_state[i+31];
if (m_state[i] < 0)
m_state[i] += 1000000000;
}
for (int i = 25; i <= 55; ++i)
{
m_state[i] = m_state[i] - m_state[i-24];
if (m_state[i] < 0)
m_state[i] += 1000000000;
}
}
public void Decrypt (byte[] input, int src, int length)
{
for (int i = src; i < length; i += 4)
{
uint key = Rand();
input[i ] ^= (byte)(key >> 24);
input[i+1] ^= (byte)(key >> 16);
input[i+2] ^= (byte)(key >> 8);
input[i+3] ^= (byte)(key);
}
}
}
}