339 lines
12 KiB
C#

//! \file ArcDRS.cs
//! \date Thu Aug 21 06:11:09 2014
//! \brief Digital Romance System archive implementation.
//
// Copyright (C) 2014-2016 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.IO;
using System.Linq;
using System.Text;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using GameRes.Utility;
using GameRes.Formats.Strings;
namespace GameRes.Formats.Ikura
{
[Export(typeof(ArchiveFormat))]
public class DrsOpener : ArchiveFormat
{
public override string Tag { get { return "DRS"; } }
public override string Description { get { return "Digital Romance System resource archive"; } }
public override uint Signature { get { return 0; } }
public override bool IsHierarchic { get { return false; } }
public override bool CanWrite { get { return false; } }
public DrsOpener ()
{
Extensions = new string[] { "", "dat", "snr" };
}
public override ArcFile TryOpen (ArcView file)
{
if (file.MaxOffset > uint.MaxValue)
return null;
int dir_size = file.View.ReadUInt16 (0);
if (dir_size < 0x20 || 0 != (dir_size & 0xf) || dir_size + 2 >= file.MaxOffset)
return null;
byte first = file.View.ReadByte (2);
if (first <= 0x20)
return null;
file.View.Reserve (0, (uint)dir_size + 2);
int dir_offset = 2;
uint next_offset = file.View.ReadUInt32 (dir_offset+12);
if (next_offset > file.MaxOffset || next_offset < dir_size+2)
return null;
int count = dir_size / 0x10 - 1;
var dir = new List<Entry> (count);
for (int i = 0; i < count; ++i)
{
var name = file.View.ReadString (dir_offset, 12);
if (string.IsNullOrEmpty (name))
return null;
uint offset = next_offset;
dir_offset += 0x10;
next_offset = file.View.ReadUInt32 (dir_offset+12);
if (next_offset > file.MaxOffset || next_offset < offset)
return null;
var entry = FormatCatalog.Instance.Create<Entry> (name);
entry.Offset = offset;
entry.Size = next_offset - offset;
dir.Add (entry);
}
return new ArcFile (file, this, dir);
}
}
[Serializable]
public class IsfScheme : ResourceScheme
{
public Dictionary<string, byte[]> KnownSecrets;
}
internal class IsfOptions : ResourceOptions
{
public byte[] Secret;
}
internal class IsfArchive : ArcFile
{
public byte[] Secret;
public IsfArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, byte[] secret = null)
: base (arc, impl, dir)
{
Secret = secret;
}
}
[Export(typeof(ArchiveFormat))]
public class MpxOpener : ArchiveFormat
{
public override string Tag { get { return "IKURA/GDL"; } }
public override string Description { get { return "IKURA GDL resource archive"; } }
public override uint Signature { get { return 0x4d324d53; } } // 'SM2M'
public override bool IsHierarchic { get { return false; } }
public override bool CanWrite { get { return false; } }
public MpxOpener ()
{
Extensions = Enumerable.Empty<string>(); // DRS archives have no extensions
}
public override ArcFile TryOpen (ArcView file)
{
if (!file.View.AsciiEqual (4, "PX10") || file.MaxOffset > uint.MaxValue)
return null;
int count = file.View.ReadInt32 (8);
if (count <= 0 || count > 0xfffff)
return null;
uint index_size = file.View.ReadUInt32 (12);
if (index_size > file.MaxOffset)
return null;
long dir_offset = 0x20;
var dir = new List<Entry> (count);
bool has_scripts = false;
for (int i = 0; i < count; ++i)
{
var name = file.View.ReadString (dir_offset, 12);
if (string.IsNullOrEmpty (name))
return null;
name = name.ToLowerInvariant();
Entry entry;
if (name.EndsWith (".isf") || name.EndsWith (".snr"))
{
entry = new Entry { Name = name, Type = "script" };
has_scripts = true;
}
else if (name.EndsWith (".bin"))
entry = new ImageEntry { Name = name };
else
entry = FormatCatalog.Instance.Create<Entry> (name);
entry.Offset = file.View.ReadUInt32 (dir_offset+12);
entry.Size = file.View.ReadUInt32 (dir_offset+16);
if (!entry.CheckPlacement (file.MaxOffset))
return null;
dir.Add (entry);
dir_offset += 0x14;
}
if (has_scripts)
return new IsfArchive (file, this, dir);
else
return new ArcFile (file, this, dir);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var isf = arc as IsfArchive;
if (null == isf || entry.Type != "script" || entry.Size <= 0x10)
return arc.File.CreateStream (entry.Offset, entry.Size);
bool encoded = arc.File.View.AsciiEqual (entry.Offset+entry.Size-0x10, "SECRETFILTER100a");
uint entry_size = entry.Size;
if (encoded)
{
entry_size -= 0x10;
if (null == isf.Secret)
isf.Secret = QuerySecret();
if (null == isf.Secret || 0 == isf.Secret.Length)
return arc.File.CreateStream (entry.Offset, entry.Size);
}
var data = new byte[entry_size];
arc.File.View.Read (entry.Offset, data, 0, entry_size);
if (encoded)
{
var decoder = new IsfDecoder (isf.Secret);
decoder.Decode (data);
}
int signature = LittleEndian.ToUInt16 (data, 4);
if (0x9795 == signature)
{
ApplyTransformation (data, 8, x => x >> 2 | x << 6);
}
else if (0xd197 == signature)
{
ApplyTransformation (data, 8, x => ~x);
}
else if (0xce89 == signature && 0 != data[6])
{
byte key = data[6];
ApplyTransformation (data, 8, x => x ^ key);
}
return new BinMemoryStream (data, entry.Name);
}
public override ResourceOptions GetDefaultOptions ()
{
return new IsfOptions {
Secret = GetSecret (Properties.Settings.Default.ISFScheme) ?? new byte[0]
};
}
public override object GetAccessWidget ()
{
return new GUI.WidgetISF();
}
private byte[] QuerySecret ()
{
var options = Query<IsfOptions> (arcStrings.ArcEncryptedNotice);
return options.Secret;
}
private static byte[] GetSecret (string scheme)
{
byte[] secret;
if (KnownSecrets.TryGetValue (scheme, out secret))
return secret;
return null;
}
private static void ApplyTransformation (byte[] data, int offset, Func<byte, int> method)
{
for (int i = offset; i < data.Length; ++i)
data[i] = (byte)method (data[i]);
}
public static Dictionary<string, byte[]> KnownSecrets = new Dictionary<string, byte[]>();
public override ResourceScheme Scheme
{
get { return new IsfScheme { KnownSecrets = KnownSecrets }; }
set { KnownSecrets = ((IsfScheme)value).KnownSecrets; }
}
}
internal class IsfDecoder
{
byte[] m_secret;
public IsfDecoder (byte[] secret)
{
m_secret = secret;
}
public void Decode (byte[] data)
{
var key_string = CreateKeyString();
int n = 0;
for (int i = 0; i < data.Length; )
{
DecodePrepare (n++, key_string);
for (int j = 0; j < key_string.Length && i < data.Length; )
{
data[i++] ^= key_string[j++];
}
}
}
private byte[] CreateKeyString ()
{
byte[] len_str = new byte[2];
for (int i = 0; i < 2; i++)
len_str[i] = EncodeHex ((byte)(Chr2HexCode (m_secret[0x500 + i]) - Chr2HexCode (m_secret[0x100 + i])));
byte[] key_string = new byte[Str2Hex (len_str)];
for (int i = 0; i < key_string.Length; i++)
key_string[i] = EncodeHex ((byte)(Chr2HexCode (m_secret[0x510 + i]) - Chr2HexCode (m_secret[0x110 + i])));
return key_string;
}
private void DecodePrepare (int index, byte[] key_string)
{
int p = (index & 0x3f) * 16; // index within SecretTable
for (int i = 0; i < key_string.Length; i++)
key_string[i] = EncodeHex ((byte)(Chr2HexCode (key_string[i]) + Chr2HexCode (m_secret[p+i])));
}
private static byte EncodeHex (byte symbol)
{
if (symbol < 0x80)
return HexEncodeMap[symbol % 36];
symbol = (byte)(-(sbyte)symbol % 36);
if (0 == symbol)
return HexEncodeMap[0];
return HexEncodeMap[36 - symbol];
}
private static byte Chr2HexCode (byte chr)
{
return HexTable[Chr2Hex (chr)];
}
private static byte Chr2Hex (byte chr)
{
byte code;
if (chr >= '0' && chr <= '9')
code = (byte)(chr - '0');
else if (chr >= 'a' && chr <= 'z')
code = (byte)(chr - 'a' + 10);
else if (chr >= 'A' && chr <= 'Z')
code = (byte)(chr - 'A' + 10);
else
code = 0;
return code;
}
private static int Str2Hex (byte[] shex)
{
int idec = 0;
for (int i = 0; i < shex.Length; ++i)
{
int mid = Chr2Hex (shex[i]);
mid <<= ((shex.Length - i - 1) << 2);
idec |= mid;
}
return idec;
}
static readonly byte[] HexEncodeMap = Encoding.ASCII.GetBytes("G5FXIL094MPRKWCJ3OEBVA7HQ2SU8Y6TZ1ND");
static readonly byte[] HexTable = new byte[] {
0x06, 0x21, 0x19, 0x10, 0x08, 0x01, 0x1E, 0x16, 0x1C, 0x07, 0x15, 0x13, 0x0E, 0x23, 0x12, 0x02,
0x00, 0x17, 0x04, 0x0F, 0x0C, 0x05, 0x09, 0x22, 0x11, 0x0A, 0x18, 0x0B, 0x1A, 0x1F, 0x1B, 0x14,
0x0D, 0x03, 0x1D, 0x20,
};
}
}