2018-11-23 06:16:26 +04:00

268 lines
10 KiB
C#

//! \file ArcFPK.cs
//! \date Fri Sep 16 04:23:31 2016
//! \brief MoonhirGames resources 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.Diagnostics;
using System.IO;
using System.Linq;
using GameRes.Utility;
namespace GameRes.Formats.MoonhirGames
{
internal class FpkEntry : Entry
{
public bool IsEncrypted;
}
internal class FpkArchive : ArcFile
{
public readonly uint Key;
public FpkArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, uint key)
: base (arc, impl, dir)
{
Key = key;
}
}
[Serializable]
public class Fpk0100Scheme : ResourceScheme
{
public uint[] KnownKeys;
}
[Export(typeof(ArchiveFormat))]
public class FpkOpener : ArchiveFormat
{
public override string Tag { get { return "FPK/MOONHIR"; } }
public override string Description { get { return "MoonhirGames engine resource archive"; } }
public override uint Signature { get { return 0x4B5046; } } // 'FPK'
public override bool IsHierarchic { get { return false; } }
public override bool CanWrite { get { return false; } }
public static uint[] KnownKeys = { 0 };
public override ResourceScheme Scheme
{
get { return new Fpk0100Scheme { KnownKeys = KnownKeys }; }
set { KnownKeys = ((Fpk0100Scheme)value).KnownKeys; }
}
public override ArcFile TryOpen (ArcView file)
{
if (!file.View.AsciiEqual (4, "0100"))
return null;
int count = file.View.ReadInt32 (0xC);
if (!IsSaneCount (count))
return null;
uint index_offset = file.View.ReadUInt32 (8);
var arc_name = Path.GetFileName (file.Name);
var fbx_type = arc_name.StartsWith ("scr", StringComparison.OrdinalIgnoreCase) ? "" : "image";
var dir = new List<Entry> (count);
bool has_encrypted = false;
for (int i = 0; i < count; ++i)
{
var name = file.View.ReadString (index_offset+12, 12);
var entry = Create<FpkEntry> (name);
entry.IsEncrypted = 0 != file.View.ReadUInt32 (index_offset);
entry.Offset = file.View.ReadUInt32 (index_offset+4);
entry.Size = file.View.ReadUInt32 (index_offset+8);
if (!entry.CheckPlacement (file.MaxOffset))
return null;
if (name.HasExtension (".fbx"))
entry.Type = fbx_type;
has_encrypted = has_encrypted || entry.IsEncrypted;
dir.Add (entry);
index_offset += 0x18;
}
if (!has_encrypted)
return new ArcFile (file, this, dir);
var enc_entry = dir.Cast<FpkEntry>().FirstOrDefault (e => e.IsEncrypted && e.Size > 8);
if (null == enc_entry)
return new ArcFile (file, this, dir);
var key = FindKey (file, enc_entry);
if (null == key)
{
Trace.WriteLine (string.Format ("{0}: unknown encryption key", file.Name), "[FPK]");
return new ArcFile (file, this, dir);
}
return new FpkArchive (file, this, dir, key.Value);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var farc = arc as FpkArchive;
var fent = entry as FpkEntry;
Stream input;
byte[] header;
if (null == farc || null == fent || !fent.IsEncrypted)
{
if (fent != null && fent.IsEncrypted)
throw new UnknownEncryptionScheme();
input = arc.File.CreateStream (entry.Offset, entry.Size);
header = new byte[0x10];
input.Read (header, 0, 0x10);
input.Position = 0;
}
else
{
var data = arc.File.View.ReadBytes (entry.Offset, entry.Size);
Decrypt (data, 0, data.Length, farc.Key);
int length = LittleEndian.ToInt32 (data, data.Length-8);
input = new BinMemoryStream (data, 0, length, entry.Name);
header = data;
}
if (!Binary.AsciiEqual (header, "FBX\x01"))
return input;
using (input)
{
int packed_size = LittleEndian.ToInt32 (header, 8);
int unpacked_size = LittleEndian.ToInt32 (header, 0xC);
input.Position = header[7];
var unpacked = UnpackFbx (input, packed_size, unpacked_size);
return new BinMemoryStream (unpacked, entry.Name);
}
}
uint? FindKey (ArcView file, Entry entry)
{
if (entry.Size < 8)
return null;
var offset = entry.Offset + entry.Size - 8;
uint t1 = file.View.ReadUInt32 (offset+4);
uint t0 = file.View.ReadUInt32 (offset);
// l = (a - x - m + 7) ^ ((x - ((b - x - m + 4) ^ x)) >> 7) ^ ((x * 2 + m - 4) << 7);
foreach (uint key in KnownKeys)
{
uint k1 = key + entry.Size - 4;
uint k2 = ((key - ((t1 - k1) ^ key)) >> 7) ^ ((k1 + key) << 7);
uint test_length = ((((t0 - (k1 - 3)) ^ k2) + 3) & ~3u) + 8;
if (entry.Size == test_length)
return key;
}
return null;
}
unsafe void Decrypt (byte[] data, int index, int length, uint key)
{
if (length < 8)
return;
fixed (byte* data8 = &data[index])
{
uint* data32 = (uint*)data8;
uint* dptr = data32 + length / 4 - 1;
uint k1 = key + (uint)length - 4;
uint k2 = key;
while (dptr >= data32)
{
*dptr = (*dptr - k1) ^ k2;
k2 = ((k2 - *dptr) >> 7) ^ ((k1 + k2) << 7);
k1 -= 3;
--dptr;
}
}
}
byte[] UnpackFbx (Stream input, int packed_size, int unpacked_size)
{
var output = new byte[unpacked_size];
int dst = 0;
int ctl = 1;
while (dst < output.Length)
{
if (1 == ctl)
{
ctl = input.ReadByte();
if (-1 == ctl)
break;
ctl |= 0x100;
}
int count, offset;
switch (ctl & 3)
{
case 0:
output[dst++] = (byte)input.ReadByte();
break;
case 1:
count = input.ReadByte();
if (-1 == count)
return output;
count = Math.Min (count + 2, output.Length - dst);
input.Read (output, dst, count);
dst += count;
break;
case 2:
offset = input.ReadByte() << 8;
offset |= input.ReadByte();
if (-1 == offset)
return output;
count = Math.Min ((offset & 0x1F) + 4, output.Length - dst);
offset >>= 5;
Binary.CopyOverlapped (output, dst - offset - 1, dst, count);
dst += count;
break;
case 3:
int exctl = input.ReadByte();
if (-1 == exctl)
return output;
count = exctl & 0x3F;
switch (exctl >> 6)
{
case 0:
count = count << 8 | input.ReadByte();
if (-1 == count)
return output;
count = Math.Min (count + 0x102, output.Length - dst);
input.Read (output, dst, count);
dst += count;
break;
case 1:
offset = input.ReadByte() << 8;
offset |= input.ReadByte();
count = count << 5 | offset & 0x1F;
count = Math.Min (count + 0x24, output.Length - dst);
offset >>= 5;
Binary.CopyOverlapped (output, dst - offset - 1, dst, count);
dst += count;
break;
case 3:
input.Seek (count, SeekOrigin.Current);
ctl = 1 << 2;
break;
default:
break;
}
break;
}
ctl >>= 2;
}
return output;
}
}
}