486 lines
19 KiB
C#

//! \file ArcLPK.cs
//! \date Mon Feb 16 17:21:47 2015
//! \brief Lucifen Easy Game System archive implementation.
//
// Copyright (C) 2015-2017 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.Linq;
using System.Text;
using GameRes.Compression;
using GameRes.Formats.Strings;
using GameRes.Utility;
namespace GameRes.Formats.Lucifen
{
internal class LuciEntry : PackedEntry
{
public byte Flag;
}
internal class LuciArchive : ArcFile
{
public LpkInfo Info;
public EncryptionScheme Scheme;
public LuciArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, EncryptionScheme scheme, LpkInfo info)
: base (arc, impl, dir)
{
Info = info;
Scheme = scheme;
}
}
[Serializable]
public class EncryptionScheme
{
public LpkOpener.Key BaseKey;
public byte ContentXor;
public uint RotatePattern;
public bool ImportGameInit;
internal void DecryptContent (byte[] data)
{
for (int i = 0; i < data.Length; ++i)
{
int v = data[i] ^ ContentXor;
data[i] = Binary.RotByteR ((byte)v, 4);
}
}
internal unsafe void DecryptEntry (byte[] data, int length, uint key)
{
uint pattern = RotatePattern;
fixed (byte* buf_raw = data)
{
uint* encoded = (uint*)buf_raw;
length /= 4;
for (int i = 0; i < length; ++i)
{
encoded[i] ^= key;
pattern = Binary.RotR (pattern, 4);
key = Binary.RotL (key, (int)pattern);
}
}
}
internal unsafe void DecryptIndex (byte[] data, int length, uint key)
{
uint pattern = RotatePattern;
fixed (byte* buf_raw = data)
{
uint* encoded = (uint*)buf_raw;
length /= 4;
for (int i = 0; i < length; ++i)
{
encoded[i] ^= key;
pattern = Binary.RotL (pattern, 4);
key = Binary.RotR (key, (int)pattern);
}
}
}
}
[Serializable]
public class LpkScheme : ResourceScheme
{
public Dictionary<string, EncryptionScheme> KnownSchemes;
public Dictionary<string, Dictionary<string, LpkOpener.Key>> KnownKeys;
}
internal class LuciOptions : ResourceOptions
{
public string Scheme;
}
internal class LpkInfo
{
public bool AlignedOffset;
public bool Flag1;
public bool IsEncrypted;
public bool PackedEntries;
public bool WholeCrypt;
public uint Key;
public byte[] Prefix;
}
[Export(typeof(ArchiveFormat))]
public class LpkOpener : ArchiveFormat
{
public override string Tag { get { return "LPK"; } }
public override string Description { get { return "Lucifen system resource archive"; } }
public override uint Signature { get { return 0x314b504c; } } // 'LPK1'
public override bool IsHierarchic { get { return true; } }
public override bool CanWrite { get { return false; } }
[Serializable]
public class Key
{
public uint Key1, Key2;
public Key (uint k1, uint k2)
{
Key1 = k1;
Key2 = k2;
}
}
static readonly EncryptionScheme DefaultScheme = new EncryptionScheme {
BaseKey = new Key (0xA5B9AC6B, 0x9A639DE5), ContentXor = 0x5d, RotatePattern = 0x31746285,
ImportGameInit = true
};
public static Dictionary<string, EncryptionScheme> KnownSchemes = new Dictionary<string, EncryptionScheme> { { "Default", DefaultScheme } };
static Dictionary<string, Dictionary<string, Key>> KnownKeys = new Dictionary<string, Dictionary<string, Key>>();
EncryptionScheme CurrentScheme = DefaultScheme;
Dictionary<string, Key> CurrentFileMap = new Dictionary<string, Key>();
public override ArcFile TryOpen (ArcView file)
{
string name = Path.GetFileName (file.Name).ToUpperInvariant();
if (string.IsNullOrEmpty (name))
return null;
Key file_key = null;
var basename = Encodings.cp932.GetBytes (Path.GetFileNameWithoutExtension (name));
if (name != "SCRIPT.LPK")
CurrentFileMap.TryGetValue (name, out file_key);
try
{
var arc = Open (basename, file, CurrentScheme, file_key);
if (null != arc)
return arc;
}
catch { /* unknown encryption, ignore parse errors */ }
var new_scheme = QueryEncryptionScheme (file.Name);
if (new_scheme == CurrentScheme && !CurrentScheme.ImportGameInit)
return null;
CurrentScheme = new_scheme;
if (name != "SCRIPT.LPK" && CurrentScheme.ImportGameInit)
{
if (0 == CurrentFileMap.Count)
ImportKeys (file.Name);
}
if (CurrentFileMap.Count > 0 && !CurrentFileMap.TryGetValue (name, out file_key))
return null;
return Open (basename, file, CurrentScheme, file_key);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
if (0 == entry.Size)
return Stream.Null;
var lent = entry as LuciEntry;
Stream input = arc.File.CreateStream (entry.Offset, entry.Size);
if (null == lent)
return input;
if (lent.IsPacked)
{
input = new LzssStream (input);
}
var larc = arc as LuciArchive;
if (null == larc)
return input;
var data = new byte[lent.UnpackedSize];
using (input)
{
input.Read (data, 0, data.Length);
}
if (larc.Info.WholeCrypt)
{
larc.Scheme.DecryptContent (data);
}
if (larc.Info.IsEncrypted)
{
int count = Math.Min (data.Length, 0x100);
if (count != 0)
larc.Scheme.DecryptEntry (data, count, larc.Info.Key);
}
input = new BinMemoryStream (data, entry.Name);
if (null != larc.Info.Prefix)
return new PrefixStream (larc.Info.Prefix, input);
else
return input;
}
ArcFile Open (byte[] basename, ArcView file, EncryptionScheme scheme, Key key)
{
uint key1 = scheme.BaseKey.Key1;
uint key2 = scheme.BaseKey.Key2;
for (int b = 0, e = basename.Length-1; e >= 0; ++b, --e)
{
key1 ^= basename[e];
key2 ^= basename[b];
key1 = Binary.RotR (key1, 7);
key2 = Binary.RotL (key2, 7);
}
if (null != key)
{
key1 ^= key.Key1;
key2 ^= key.Key2;
}
uint code = file.View.ReadUInt32 (4) ^ key2;
int index_size = (int)(code & 0xffffff);
byte flags = (byte)(code >> 24);
if (0 != (flags & 1))
index_size = (index_size << 11) - 8;
if (index_size < 5 || index_size >= file.MaxOffset)
return null;
var index = new byte[index_size];
if (index_size != file.View.Read (8, index, 0, (uint)index_size))
return null;
scheme.DecryptIndex (index, index_size, key2);
var lpk_info = new LpkInfo
{
AlignedOffset = 0 != (flags & 1),
Flag1 = 0 != (flags & 2),
IsEncrypted = 0 != (flags & 4),
PackedEntries = 0 != (flags & 8),
WholeCrypt = 0 != (flags & 0x10),
Key = key1
};
var reader = new IndexReader (lpk_info);
var dir = reader.Read (index);
if (null == dir)
return null;
// this condition is fishy, probably patch files have additional bitflag set
if (lpk_info.WholeCrypt && Binary.AsciiEqual (basename, "PATCH"))
lpk_info.WholeCrypt = false;
return new LuciArchive (file, this, dir, scheme, reader.Info);
}
static readonly byte[] ScriptName = Encoding.ASCII.GetBytes ("SCRIPT");
void ImportKeys (string source_name)
{
var script_lpk = VFS.CombinePath (Path.GetDirectoryName (source_name), "SCRIPT.LPK");
using (var script_file = VFS.OpenView (script_lpk))
using (var script_arc = Open (ScriptName, script_file, CurrentScheme, null))
{
if (null == script_arc)
throw new UnknownEncryptionScheme();
var entry = script_arc.Dir.FirstOrDefault (e => e.Name.Equals ("gameinit.sob", StringComparison.InvariantCultureIgnoreCase));
if (null == entry)
throw new FileNotFoundException ("Missing 'gameinit.sob' entry in SCRIPT.LPK");
using (var gameinit = script_arc.OpenEntry (entry))
{
var init_data = new byte[gameinit.Length];
gameinit.Read (init_data, 0, init_data.Length);
if (!ParseGameInit (init_data))
throw new UnknownEncryptionScheme();
}
}
}
bool ParseGameInit (byte[] sob)
{
CurrentFileMap.Clear();
if (!Binary.AsciiEqual (sob, "SOB0"))
return false;
int offset = LittleEndian.ToInt32 (sob, 4) + 8;
if (offset <= 0 || offset >= sob.Length)
return false;
unsafe
{
fixed (byte* buf_raw = sob)
{
uint* p = (uint*)(buf_raw + offset);
uint index_len = *p;
if (offset+8+(int)index_len >= sob.Length)
return false;
p += 2;
uint* last = p + index_len / 4 - 28;
while (p < last)
{
if (p[0] == 0x28 && p[1] == 0 && p[2] != 0 && p[3] == 8 &&
p[4] == 1 && p[5] == 8 && p[6] == 1 && p[7] == 8 &&
p[8] != 0 && p[9] == 8 && p[10] != 0 && p[11] == 5 &&
p[17] == 0x28 && p[18] == 0 && p[19] != 0 && p[20] == 8 &&
p[21] != 0 && p[22] == 8 && p[23] == 0xffffffff && p[24] == 8 &&
p[25] == 1 && p[26] == 8 && p[27] == 1 && p[28] == 5)
{
byte* lpk = (byte*)p + p[21] - p[2] + 0x34;
int name_index = (int)(lpk - buf_raw);
if (name_index < 0 || name_index >= sob.Length)
{
++p;
continue;
}
string name = Binary.GetCString (sob, name_index, sob.Length-name_index);
name = name.ToUpperInvariant();
CurrentFileMap[name] = new Key (p[8], p[10]);
p += 0x22;
} else
++p;
}
return CurrentFileMap.Count > 0;
}
}
}
public override ResourceOptions GetDefaultOptions ()
{
return new LuciOptions { Scheme = Properties.Settings.Default.LPKScheme };
}
public override object GetAccessWidget ()
{
return new GUI.WidgetLPK();
}
EncryptionScheme QueryEncryptionScheme (string arc_name)
{
CurrentFileMap.Clear();
string title = FormatCatalog.Instance.LookupGame (arc_name);
Dictionary<string, Key> file_map;
if (!string.IsNullOrEmpty (title) && KnownSchemes.ContainsKey (title))
{
if (KnownKeys.TryGetValue (title, out file_map))
CurrentFileMap = new Dictionary<string, Key> (file_map);
return KnownSchemes[title];
}
var options = Query<LuciOptions> (arcStrings.ArcEncryptedNotice);
if (null == options)
return DefaultScheme;
title = options.Scheme;
if (KnownKeys.TryGetValue (title, out file_map))
CurrentFileMap = new Dictionary<string, Key> (file_map);
return KnownSchemes[title];
}
public override ResourceScheme Scheme
{
get { return new LpkScheme { KnownSchemes = KnownSchemes, KnownKeys = KnownKeys }; }
set
{
var scheme = (LpkScheme)value;
KnownSchemes = scheme.KnownSchemes;
KnownKeys = scheme.KnownKeys;
foreach (var key in KnownSchemes.Keys.Where (x => null == KnownSchemes[x]).ToArray())
{
KnownSchemes[key] = DefaultScheme;
}
}
}
}
internal class IndexReader
{
byte[] m_index;
LpkInfo m_info;
List<Entry> m_dir;
byte[] m_name;
int m_index_width;
int m_entries_offset;
public LpkInfo Info { get { return m_info; } }
public int EntrySize { get; private set; }
public IndexReader (LpkInfo info)
{
if (!info.Flag1)
throw new NotSupportedException ("Not supported LPK index format");
m_info = info;
EntrySize = m_info.PackedEntries ? 13 : 9;
}
public List<Entry> Read (byte[] index)
{
m_index = index;
int count = LittleEndian.ToInt32 (m_index, 0);
if (!ArchiveFormat.IsSaneCount (count))
return null;
int index_offset = 4;
int prefix_length = m_index[index_offset++];
if (0 != prefix_length)
{
m_info.Prefix = new byte[prefix_length];
Buffer.BlockCopy (m_index, index_offset, m_info.Prefix, 0, prefix_length);
index_offset += prefix_length;
}
m_index_width = 0 != m_index[index_offset++] ? 4 : 2;
int letter_table_length = LittleEndian.ToInt32 (m_index, index_offset);
index_offset += 4;
m_entries_offset = index_offset + letter_table_length;
if (m_entries_offset >= m_index.Length)
return null;
if ((m_index.Length - m_entries_offset) / EntrySize < count)
EntrySize = (m_index.Length - m_entries_offset) / count;
if (EntrySize < 8 || m_info.PackedEntries && EntrySize < 12)
return null;
m_dir = new List<Entry> (count);
m_name = new byte[260];
TraverseIndex (index_offset, 0);
return m_dir.Count == count ? m_dir : null;
}
void TraverseIndex (int index_offset, int name_length)
{
if (index_offset < 0 || index_offset >= m_index.Length)
throw new InvalidFormatException ("Error parsing LPK index");
if (name_length >= m_name.Length)
throw new InvalidFormatException ("Entry filename is too long");
int entries = m_index[index_offset++];
for (int i = 0; i < entries; ++i)
{
byte next_letter = m_index[index_offset++];
int next_offset = 4 == m_index_width ? LittleEndian.ToInt32 (m_index, index_offset)
: (int)LittleEndian.ToUInt16 (m_index, index_offset);
m_name[name_length] = next_letter;
index_offset += m_index_width;;
if (0 != next_letter)
TraverseIndex (index_offset+next_offset, name_length+1);
else
AddEntry (name_length, next_offset);
}
}
void AddEntry (int name_length, int entry_num)
{
if (name_length < 1)
throw new InvalidFormatException ("Invalid LPK entry name");
string name = Encodings.cp932.GetString (m_name, 0, name_length);
var entry = FormatCatalog.Instance.Create<LuciEntry> (name);
int entry_pos = m_entries_offset + EntrySize * entry_num;
if (entry_pos+EntrySize > m_index.Length)
throw new InvalidFormatException ("Invalid LPK entry index");
if (0 != (EntrySize & 1))
entry.Flag = m_index[entry_pos++];
long offset = LittleEndian.ToUInt32 (m_index, entry_pos);
entry.Offset = m_info.AlignedOffset ? offset << 11 : offset;
entry.Size = LittleEndian.ToUInt32 (m_index, entry_pos+4);
entry.UnpackedSize = entry.Size;
if (m_info.PackedEntries)
{
uint unpacked_size = LittleEndian.ToUInt32 (m_index, entry_pos+8);
entry.IsPacked = unpacked_size != 0;
if (entry.IsPacked)
entry.UnpackedSize = unpacked_size;
}
m_dir.Add (entry);
}
}
}