GARbro-mirror/ArcFormats/ArcAVC.cs

204 lines
7.7 KiB
C#

//! \file ArcAVC.cs
//! \date Sun Mar 15 20:41:17 2015
//! \brief AVC engine resource archive.
//
// Copyright (C) 2015 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.Utility;
namespace GameRes.Formats.AVC
{
public class ArchiveFile : ArcFile
{
public readonly byte[] Key;
public readonly int HeaderOffset;
public ArchiveFile (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, int offset, byte[] key)
: base (arc, impl, dir)
{
HeaderOffset = offset;
Key = key;
}
}
[Serializable]
public class ArchiveScheme
{
public string Password;
public int KeyOffset;
public int HeaderOffset;
};
[Serializable]
public class AvcScheme : ResourceScheme
{
public ArchiveScheme[] KnownSchemes;
}
[Export(typeof(ArchiveFormat))]
public class DatOpener : ArchiveFormat
{
public override string Tag { get { return "AVC"; } }
public override string Description { get { return "AVC engine resource archive"; } }
public override uint Signature { get { return 0; } }
public override bool IsHierarchic { get { return false; } }
public override bool CanCreate { get { return false; } }
public DatOpener ()
{
Extensions = new string[] { "dat" };
}
public override ArcFile TryOpen (ArcView file)
{
var reader = new AdvReader (file);
var dir = reader.GetIndex();
if (null == dir)
return null;
return new ArchiveFile (file, this, dir, reader.HeaderOffset, reader.Key);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var arcf = arc as ArchiveFile;
if (null == arcf)
return arc.File.CreateStream (entry.Offset, entry.Size);
var data = new byte[entry.Size];
arc.File.View.Read (entry.Offset, data, 0, entry.Size);
int base_offset = (int)(entry.Offset-arcf.HeaderOffset);
for (int i = 0; i < data.Length; ++i)
data[i] ^= arcf.Key[((base_offset+i)&7)];
return new MemoryStream (data, false);
}
internal class AdvReader
{
ArcView m_file;
byte[] m_input = new byte[0x80];
byte[] m_header = new byte[0x24];
byte[] m_key = new byte[8];
byte[] m_index;
int m_index_offset;
int m_count;
int m_header_offset;
public byte[] Key { get { return m_key; } }
public int HeaderOffset { get { return m_header_offset; } }
public AdvReader (ArcView file)
{
m_file = file;
}
public List<Entry> GetIndex ()
{
if (m_input.Length != m_file.View.Read (0, m_input, 0, (uint)m_input.Length))
return null;
foreach (var scheme in KnownSchemes)
{
if (!ReadIndex (scheme.KeyOffset, scheme.HeaderOffset))
continue;
try
{
var dir = ParseIndex();
if (null != dir)
return dir;
}
catch { /* ignore parse errors */ }
}
return null;
}
bool ReadIndex (int key_offset, int header_offset)
{
// placing predefined string into XORed file is a very smart move
for (int i = 0; i < 8; ++i)
{
var symbol = m_input[header_offset+i] ^ "ARCHIVE\0"[i];
var check = m_input[key_offset+i] ^ symbol;
if (check < 0x20 || check > 0x7e)
return false;
Key[i] = (byte)symbol;
}
for (int i = 0x10; i < 0x24; ++i)
m_header[i] = (byte)(m_input[header_offset+i] ^ Key[i&7]);
int entry_size = LittleEndian.ToInt32 (m_header, 0x14);
if (0x114 != entry_size)
return false;
m_index_offset = LittleEndian.ToInt32 (m_header, 0x10);
m_count = LittleEndian.ToInt32 (m_header, 0x20);
if (m_index_offset < 0x24 || (long)m_index_offset+header_offset >= m_file.MaxOffset
|| m_count <= 0 || m_count > 0xffff)
return false;
int index_size = entry_size * m_count;
if (null == m_index || m_index.Length < index_size)
m_index = new byte[index_size];
if (index_size != m_file.View.Read (m_index_offset+header_offset, m_index, 0, (uint)index_size))
return false;
m_header_offset = header_offset;
return true;
}
List<Entry> ParseIndex()
{
for (int i = 0; i < 0x114 * m_count; ++i)
m_index[i] ^= Key[(m_index_offset+i)&7];
var dir = new List<Entry> (m_count);
int index_offset = 0;
for (int i = 0; i < m_count; ++i)
{
if (0 != m_index[index_offset++])
return null;
int name_length = 0;
while (name_length < 0x100 && 0 != m_index[index_offset+name_length])
name_length++;
if (0 == name_length)
{
index_offset += 0x113;
continue;
}
var name = Encodings.cp932.GetString (m_index, index_offset, name_length);
var entry = FormatCatalog.Instance.Create<Entry> (name);
index_offset += 0x107;
entry.Offset = m_header_offset + LittleEndian.ToUInt32 (m_index, index_offset);
entry.Size = LittleEndian.ToUInt32 (m_index, index_offset+4);
index_offset += 0x0c;
dir.Add (entry);
}
return dir;
}
internal static ArchiveScheme[] KnownSchemes = new ArchiveScheme[0];
}
public override ResourceScheme Scheme
{
get { return new AvcScheme { KnownSchemes = AdvReader.KnownSchemes }; }
set { AdvReader.KnownSchemes = ((AvcScheme)value).KnownSchemes; }
}
}
}