GARbro-mirror/ArcFormats/NSystem/ArcFJSYS.cs

215 lines
7.9 KiB
C#

//! \file ArcFJSYS.cs
//! \date Thu Nov 24 14:00:07 2016
//! \brief NSystem engine resource archive.
//
// Copyright (C) 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.Security.Cryptography;
using System.Text;
using GameRes.Formats.Strings;
using GameRes.Utility;
namespace GameRes.Formats.NSystem
{
internal class MsdArchive : ArcFile
{
public readonly string Key;
public MsdArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, string key)
: base (arc, impl, dir)
{
Key = key;
}
}
[Export(typeof(ArchiveFormat))]
public class FjsysOpener : ArchiveFormat
{
public override string Tag { get { return "FJSYS"; } }
public override string Description { get { return "NSystem engine resource archive"; } }
public override uint Signature { get { return 0x59534A46; } } // 'FJSY'
public override bool IsHierarchic { get { return false; } }
public override bool CanWrite { get { return false; } }
public FjsysOpener ()
{
Extensions = new string[] { "" };
}
public override ArcFile TryOpen (ArcView file)
{
if (file.View.ReadByte (4) != 'S')
return null;
uint names_size = file.View.ReadUInt32 (0xC);
int count = file.View.ReadInt32 (0x10);
if (!IsSaneCount (count))
return null;
uint index_offset = 0x54;
uint index_size = (uint)count * 0x10;
var names = file.View.ReadBytes (index_offset + index_size, names_size);
var dir = new List<Entry> (count);
bool has_scripts = false;
for (int i = 0; i < count; ++i)
{
var name_offset = file.View.ReadInt32 (index_offset);
var name = Binary.GetCString (names, name_offset);
var entry = FormatCatalog.Instance.Create<Entry> (name);
entry.Size = file.View.ReadUInt32 (index_offset+4);
entry.Offset = file.View.ReadInt64 (index_offset+8);
if (!entry.CheckPlacement (file.MaxOffset))
return null;
has_scripts = has_scripts || name.HasExtension (".msd");
dir.Add (entry);
index_offset += 0x10;
}
if (has_scripts)
{
var password = QueryPassword (file.Name);
if (!string.IsNullOrEmpty (password))
return new MsdArchive (file, this, dir, password);
}
return new ArcFile (file, this, dir);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var msarc = arc as MsdArchive;
if (null == msarc || string.IsNullOrEmpty (msarc.Key)
|| !entry.Name.HasExtension (".msd")
|| arc.File.View.AsciiEqual (entry.Offset, "MSCENARIO FILE "))
return base.OpenEntry (arc, entry);
var input = arc.File.CreateStream (entry.Offset, entry.Size);
return new InputCryptoStream (input, new MsdTransform (msarc.Key));
}
string QueryPassword (string arc_name)
{
var title = FormatCatalog.Instance.LookupGame (arc_name);
if (!string.IsNullOrEmpty (title) && KnownPasswords.ContainsKey (title))
return KnownPasswords[title];
var options = Query<FjsysOptions> (arcStrings.FJSYSNotice);
return options.MsdPassword;
}
public override ResourceOptions GetDefaultOptions ()
{
return new FjsysOptions { MsdPassword = Properties.Settings.Default.FJSYSPassword };
}
public override object GetAccessWidget ()
{
return new GUI.WidgetMSD();
}
public static Dictionary<string, string> KnownPasswords = new Dictionary<string, string>();
public override ResourceScheme Scheme
{
get { return new FjsysScheme { MsdPasswords = KnownPasswords }; }
set { KnownPasswords = ((FjsysScheme)value).MsdPasswords; }
}
}
internal sealed class MsdTransform : ICryptoTransform
{
const int BlockSize = 0x20;
string m_key;
MD5 m_md5;
StringBuilder m_hash_str;
int m_block_num;
public bool CanReuseTransform { get { return false; } }
public bool CanTransformMultipleBlocks { get { return true; } }
public int InputBlockSize { get { return BlockSize; } }
public int OutputBlockSize { get { return BlockSize; } }
public MsdTransform (string key)
{
m_key = key;
m_md5 = MD5.Create();
m_hash_str = new StringBuilder (BlockSize);
m_block_num = 0;
}
public int TransformBlock (byte[] inputBuffer, int inputOffset, int inputCount,
byte[] outputBuffer, int outputOffset)
{
int block_count = inputCount / BlockSize;
for (int i = 0; i < block_count; ++i)
{
DoTransform (inputBuffer, inputOffset, BlockSize, outputBuffer, outputOffset);
inputOffset += BlockSize;
outputOffset += BlockSize;
}
return inputCount;
}
public byte[] TransformFinalBlock (byte[] inputBuffer, int inputOffset, int inputCount)
{
byte[] outputBuffer = new byte[inputCount];
DoTransform (inputBuffer, inputOffset, inputCount, outputBuffer, 0);
return outputBuffer;
}
void DoTransform (byte[] input, int src, int count, byte[] output, int dst)
{
string chunk_key_str = m_key + m_block_num.ToString();
++m_block_num;
var chunk_key = Encodings.cp932.GetBytes (chunk_key_str);
var hash = m_md5.ComputeHash (chunk_key);
m_hash_str.Clear();
for (int j = 0; j < hash.Length; ++j)
m_hash_str.AppendFormat ("{0:x2}", hash[j]);
count = Math.Min (m_hash_str.Length, count);
for (int k = 0; k < count; ++k)
output[dst++] = (byte)(input[src++] ^ m_hash_str[k]);
}
bool _disposed = false;
public void Dispose ()
{
if (!_disposed)
{
m_md5.Dispose();
_disposed = true;
}
GC.SuppressFinalize (this);
}
}
[Serializable]
public class FjsysScheme : ResourceScheme
{
public Dictionary<string, string> MsdPasswords;
}
public class FjsysOptions : ResourceOptions
{
public string MsdPassword;
}
}