Public-Mirror/GARbro-mirror
1
0
Fork 0
mirror of https://github.com/crskycode/GARbro.git synced 2024-10-22 23:28:16 +08:00
Code Issues Projects Releases Wiki Activity

(PCF): alternative encryption scheme.

Browse Source
This commit is contained in:
morkt 2017-07-15 06:03:04 +04:00
parent 37539cc083
commit cbab8b200a
1 changed files with 116 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

156
ArcFormats/Primel/ArcPCF.cs
View File

@ -2,7 +2,7 @@
//! \date Fri Sep 30 10:37:28 2016
//! \brief Primel the Adventure System resource archive.
//
// Copyright (C) 2016 by morkt
// Copyright (C) 2016-2017 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
@ -35,8 +35,19 @@ namespace GameRes.Formats.Primel
{
internal class PcfEntry : PackedEntry
{
public uint Flags;
public IEnumerable<byte> Key;
public uint Flags;
public byte[] Key;
}
internal class PcfArchive : ArcFile
{
public readonly PrimelScheme Scheme;
public PcfArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, PrimelScheme scheme)
: base (arc, impl, dir)
{
Scheme = scheme;
}
}
[Export(typeof(ArchiveFormat))]
@ -55,49 +66,23 @@ namespace GameRes.Formats.Primel
int count = file.View.ReadInt32 (8);
if (!IsSaneCount (count))
return null;
long data_size = file.View.ReadInt64 (0x10);
long index_offset = file.View.ReadInt64 (0x28);
if (data_size >= file.MaxOffset || index_offset >= file.MaxOffset)
var reader = new PcfIndexReader (file, count);
var dir = reader.Read();
if (null == dir)
return null;
uint index_size = file.View.ReadUInt32 (0x30);
uint flags = file.View.ReadUInt32 (0x38);
var key = file.View.ReadBytes (0x58, 8);
long base_offset = file.MaxOffset - data_size;
using (var stream = file.CreateStream (base_offset + index_offset, index_size))
using (var index = ReadFile (stream, key, flags))
{
var buffer = new byte[0x80];
var dir = new List<Entry> (count);
for (int i = 0; i < count; ++i)
{
if (buffer.Length != index.Read (buffer, 0, buffer.Length))
break;
var name = Binary.GetCString (buffer, 0, 0x50);
var entry = FormatCatalog.Instance.Create<PcfEntry> (name);
entry.Offset = LittleEndian.ToInt64 (buffer, 0x50) + base_offset;
entry.UnpackedSize = LittleEndian.ToUInt32 (buffer, 0x58);
entry.Size = LittleEndian.ToUInt32 (buffer, 0x60);
if (!entry.CheckPlacement (file.MaxOffset))
return null;
entry.Flags = LittleEndian.ToUInt32 (buffer, 0x68);
entry.Key = new ArraySegment<byte> (buffer, 0x78, 8).ToArray();
entry.IsPacked = entry.UnpackedSize != entry.Size;
dir.Add (entry);
}
return new ArcFile (file, this, dir);
}
return new PcfArchive (file, this, dir, reader.Scheme);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var parc = arc as PcfArchive;
var pent = entry as PcfEntry;
if (null == pent)
if (null == pent || null == parc)
return base.OpenEntry (arc, entry);
Stream input = arc.File.CreateStream (entry.Offset, entry.Size);
try
{
input = ReadFile (input, pent.Key, pent.Flags);
input = parc.Scheme.TransformStream (input, pent.Key, pent.Flags);
if (pent.IsPacked)
input = new LimitStream (input, pent.UnpackedSize);
return input;
@ -108,8 +93,85 @@ namespace GameRes.Formats.Primel
throw;
}
}
}
Stream ReadFile (Stream input, IEnumerable<byte> key, uint flags)
internal sealed class PcfIndexReader
{
ArcView m_file;
int m_count;
long m_base_offset;
List<Entry> m_dir;
public PrimelScheme Scheme { get; set; }
public PcfIndexReader (ArcView file, int count)
{
m_file = file;
m_count = count;
m_dir = new List<Entry> (m_count);
}
static readonly PrimelScheme[] KnownSchemes = {
new PrimelScheme(), new PrimelSchemeV2()
};
public List<Entry> Read ()
{
long data_size = m_file.View.ReadInt64 (0x10);
long index_offset = m_file.View.ReadInt64 (0x28);
if (data_size >= m_file.MaxOffset || index_offset >= m_file.MaxOffset)
return null;
uint index_size = m_file.View.ReadUInt32 (0x30);
uint flags = m_file.View.ReadUInt32 (0x38);
var key = m_file.View.ReadBytes (0x58, 8);
m_base_offset = m_file.MaxOffset - data_size;
foreach (var scheme in KnownSchemes)
{
m_dir.Clear();
try
{
using (var stream = m_file.CreateStream (m_base_offset + index_offset, index_size))
using (var index = scheme.TransformStream (stream, key, flags))
{
if (ReadIndex (index))
{
this.Scheme = scheme;
return m_dir;
}
}
}
catch { /* invalid scheme, retry */ }
}
return null;
}
byte[] m_buffer = new byte[0x80];
bool ReadIndex (Stream index)
{
for (int i = 0; i < m_count; ++i)
{
if (m_buffer.Length != index.Read (m_buffer, 0, m_buffer.Length))
break;
var name = Binary.GetCString (m_buffer, 0, 0x50);
var entry = FormatCatalog.Instance.Create<PcfEntry> (name);
entry.Offset = LittleEndian.ToInt64 (m_buffer, 0x50) + m_base_offset;
entry.UnpackedSize = LittleEndian.ToUInt32 (m_buffer, 0x58);
entry.Size = LittleEndian.ToUInt32 (m_buffer, 0x60);
if (!entry.CheckPlacement (m_file.MaxOffset))
return false;
entry.Flags = LittleEndian.ToUInt32 (m_buffer, 0x68);
entry.Key = new ArraySegment<byte> (m_buffer, 0x78, 8).ToArray();
entry.IsPacked = entry.UnpackedSize != entry.Size;
m_dir.Add (entry);
}
return m_dir.Count > 0;
}
}
internal class PrimelScheme
{
public Stream TransformStream (Stream input, byte[] key, uint flags)
{
var key1 = GenerateKey (key);
var iv = GenerateKey (key1);
@ -168,10 +230,9 @@ namespace GameRes.Formats.Primel
}
}
byte[] GenerateKey (IEnumerable<byte> seed)
byte[] GenerateKey (byte[] seed)
{
var sha = new Primel.SHA256();
var hash = sha.ComputeHash (seed.ToArray());
var hash = ComputeHash (seed);
var key = new byte[0x10];
for (int i = 0; i < hash.Length; ++i)
{
@ -179,5 +240,20 @@ namespace GameRes.Formats.Primel
}
return key;
}
protected virtual byte[] ComputeHash (byte[] seed)
{
var sha = new Primel.SHA256();
return sha.ComputeHash (seed);
}
}
internal class PrimelSchemeV2 : PrimelScheme
{
protected override byte[] ComputeHash (byte[] seed)
{
using (var sha = System.Security.Cryptography.SHA256.Create())
return sha.ComputeHash (seed);
}
}
}