GARbro-mirror/ArcFormats/Kaguya/ArcLINK.cs

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//! \file ArcLINK.cs
//! \date Fri Jan 22 18:44:56 2016
//! \brief KaGuYa archive format.
//
// 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
// 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;
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using System.Text;
namespace GameRes.Formats.Kaguya
{
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internal class LinkEntry : PackedEntry
{
public bool IsEncrypted;
}
internal class LinkArchive : ArcFile
{
public readonly LinkEncryption Encryption;
public LinkArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, LinkEncryption enc)
: base (arc, impl, dir)
{
Encryption = enc;
}
}
[Export(typeof(ArchiveFormat))]
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public class LinkOpener : ArchiveFormat
{
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public override string Tag { get { return "ARC/LINK"; } }
public override string Description { get { return "KaGuYa script engine resource archive"; } }
public override uint Signature { get { return 0x4B4E494C; } } // 'LINK'
public override bool IsHierarchic { get { return false; } }
public override bool CanWrite { get { return false; } }
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public LinkOpener ()
{
Extensions = new string[] { "arc" };
}
public override ArcFile TryOpen (ArcView file)
{
int version = file.View.ReadByte (4) - '0';
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if (version < 3 || version > 6)
return ReadOldIndex (file);
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using (var reader = LinkReader.Create (file, version))
{
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var dir = reader.ReadIndex();
if (null == dir)
return null;
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if (reader.HasEncrypted)
{
var enc = reader.GetEncryption();
if (enc != null)
return new LinkArchive (file, this, dir, enc);
}
return new ArcFile (file, this, dir);
}
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
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var lent = entry as LinkEntry;
if (null == lent || (!lent.IsPacked && !lent.IsEncrypted))
{
if (entry.Size > 8)
{
uint unpacked_size = arc.File.View.ReadUInt32 (entry.Offset);
int id = arc.File.View.ReadUInt16 (entry.Offset+5);
if (id == 0x4D42) // 'BM'
{
using (var input = arc.File.CreateStream (entry.Offset+4, entry.Size-4, entry.Name))
{
var data = Lin2Opener.UnpackLzss (input, unpacked_size);
return new BinMemoryStream (data, entry.Name);
}
}
}
return base.OpenEntry (arc, entry);
}
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if (lent.IsEncrypted)
{
var larc = arc as LinkArchive;
if (null == larc)
return base.OpenEntry (arc, entry);
return larc.Encryption.DecryptEntry (larc, lent);
}
using (var input = arc.File.CreateStream (entry.Offset, entry.Size))
using (var bmr = new BmrDecoder (input))
{
bmr.Unpack();
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return new BinMemoryStream (bmr.Data, entry.Name);
}
}
internal ArcFile ReadOldIndex (ArcView file)
{
int count = file.View.ReadInt32 (4);
if (!IsSaneCount (count))
return null;
var dir = new List<Entry> (count);
using (var index = file.CreateStream())
{
index.Position = 8;
uint names_size = index.ReadUInt32();
for (int i = 0; i < count; ++i)
{
var name = index.ReadCString();
var entry = FormatCatalog.Instance.Create<Entry> (name);
dir.Add (entry);
}
index.Position = 12 + names_size;
foreach (var entry in dir)
{
entry.Offset = index.ReadUInt32();
entry.Size = index.ReadUInt32();
if (!entry.CheckPlacement (file.MaxOffset))
return null;
}
}
return new ArcFile (file, this, dir);
}
}
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internal class LinkReader : IDisposable
{
IBinaryStream m_input;
readonly long m_max_offset;
bool m_has_encrypted;
protected LinkReader (ArcView file)
{
m_input = file.CreateStream();
m_max_offset = file.MaxOffset;
m_has_encrypted = false;
}
public IBinaryStream Input { get { return m_input; } }
public bool HasEncrypted { get { return m_has_encrypted; } }
public static LinkReader Create (ArcView file, int version)
{
if (version < 4)
return new LinkReader (file);
else if (version < 6)
return new Link4Reader (file);
else
return new Link6Reader (file);
}
protected virtual long GetDataOffset ()
{
return 8;
}
protected virtual string ReadName ()
{
int name_length = m_input.ReadUInt8();
Skip (2);
return m_input.ReadCString (name_length);
}
public List<Entry> ReadIndex ()
{
m_input.Position = GetDataOffset();
var header = new byte[4];
var dir = new List<Entry>();
while (m_input.Position + 4 < m_max_offset)
{
long base_offset = m_input.Position;
uint size = m_input.ReadUInt32();
if (0 == size)
break;
if (size < 0x10)
return null;
int flags = m_input.ReadUInt16 ();
bool is_compressed = (flags & 3) != 0;
Skip (7);
var name = ReadName();
if (string.IsNullOrEmpty (name))
return null;
var entry = FormatCatalog.Instance.Create<LinkEntry> (name);
entry.Offset = m_input.Position;
entry.Size = size - (uint)(entry.Offset - base_offset);
if (is_compressed)
{
m_input.Read (header, 0, 4);
if (header.AsciiEqual ("BMR"))
{
entry.IsPacked = true;
entry.UnpackedSize = m_input.ReadUInt32();
}
}
entry.IsEncrypted = (flags & 4) != 0;
m_has_encrypted = m_has_encrypted || entry.IsEncrypted;
dir.Add (entry);
m_input.Position = entry.Offset + entry.Size;
}
return dir;
}
public virtual LinkEncryption GetEncryption ()
{
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var params_dat = VFS.ChangeFileName (m_input.Name, "params.dat");
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if (!VFS.FileExists (params_dat))
return null;
using (var input = VFS.OpenBinaryStream (params_dat))
{
var param = ParamsDeserializer.Create (input);
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return param.GetEncryption();
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}
}
protected void Skip (int amount)
{
m_input.Seek (amount, SeekOrigin.Current);
}
#region IDisposable Members
public void Dispose ()
{
Dispose (true);
GC.SuppressFinalize (this);
}
bool _disposed = false;
protected virtual void Dispose (bool disposing)
{
if (!_disposed)
{
if (disposing)
m_input.Dispose();
_disposed = true;
}
}
#endregion
}
internal class Link4Reader : LinkReader
{
public Link4Reader (ArcView file) : base (file)
{
}
protected override long GetDataOffset ()
{
return 0xA;
}
}
internal class Link6Reader : LinkReader
{
public Link6Reader (ArcView file) : base (file)
{
}
protected override long GetDataOffset ()
{
Input.Position = 7;
return 8 + Input.ReadUInt8();
}
byte[] name_buffer = new byte[0x100];
protected override string ReadName ()
{
int name_length = Input.ReadUInt16();
if (name_length > 0x400)
throw new InvalidFormatException();
if (name_length > name_buffer.Length)
name_buffer = new byte[name_length];
Input.Read (name_buffer, 0, name_length);
return Encoding.Unicode.GetString (name_buffer, 0, name_length);
}
}
internal class BmrDecoder : IDisposable
{
byte[] m_output;
MsbBitStream m_input;
int m_final_size;
int m_step;
int m_key;
public byte[] Data { get { return m_output; } }
public BmrDecoder (IBinaryStream input)
{
input.Position = 3;
m_step = input.ReadUInt8();
m_final_size = input.ReadInt32();
m_key = input.ReadInt32();
int unpacked_size = input.ReadInt32();
m_output = new byte[unpacked_size];
m_input = new MsbBitStream (input.AsStream, true);
}
public void Unpack ()
{
m_input.Input.Position = 0x14;
UnpackHuffman();
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UndoMoveToFront();
m_output = Decode (m_output, m_key);
if (m_step != 0)
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m_output = DecompressRLE (m_output);
}
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byte[] DecompressRLE (byte[] input)
{
var result = new byte[m_final_size];
int src = 0;
for (int i = 0; i < m_step; ++i)
{
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byte v1 = input[src++];
result[i] = v1;
int dst = i + m_step;
while (dst < result.Length)
{
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byte v2 = input[src++];
result[dst] = v2;
dst += m_step;
if (v2 == v1)
{
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int count = input[src++];
if (0 != (count & 0x80))
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count = input[src++] + ((count & 0x7F) << 8) + 128;
while (count --> 0 && dst < result.Length)
{
result[dst] = v2;
dst += m_step;
}
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if (dst < result.Length)
{
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v2 = input[src++];
result[dst] = v2;
dst += m_step;
}
}
v1 = v2;
}
}
return result;
}
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void UndoMoveToFront ()
{
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var dict = new byte[256];
for (int i = 0; i < 256; ++i)
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dict[i] = (byte)i;
for (int i = 0; i < m_output.Length; ++i)
{
byte v = m_output[i];
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m_output[i] = dict[v];
for (int j = v; j > 0; --j)
{
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dict[j] = dict[j-1];
}
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dict[0] = m_output[i];
}
}
byte[] Decode (byte[] input, int key)
{
var freq_table = new int[256];
for (int i = 0; i < input.Length; ++i)
{
++freq_table[input[i]];
}
for (int i = 1; i < 256; ++i)
{
freq_table[i] += freq_table[i-1];
}
var distrib_table = new int[input.Length];
for (int i = input.Length-1; i >= 0; --i)
{
int v = input[i];
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int freq = --freq_table[v];
distrib_table[freq] = i;
}
int pos = key;
var copy_out = new byte[input.Length];
for (int i = 0; i < copy_out.Length; ++i)
{
pos = distrib_table[pos];
copy_out[i] = input[pos];
}
return copy_out;
}
ushort m_token;
ushort[,] m_tree = new ushort[2,256];
void UnpackHuffman ()
{
m_token = 256;
ushort root = CreateHuffmanTree();
int dst = 0;
while (dst < m_output.Length)
{
ushort symbol = root;
while (symbol >= 0x100)
{
int bit = m_input.GetNextBit();
if (-1 == bit)
throw new EndOfStreamException();
symbol = m_tree[bit,symbol-256];
}
m_output[dst++] = (byte)symbol;
}
}
ushort CreateHuffmanTree ()
{
if (0 != m_input.GetNextBit())
{
ushort v = m_token++;
m_tree[0,v-256] = CreateHuffmanTree();
m_tree[1,v-256] = CreateHuffmanTree();
return v;
}
else
{
return (ushort)m_input.GetBits (8);
}
}
#region IDisposable Members
bool _disposed = false;
public void Dispose ()
{
if (!_disposed)
{
m_input.Dispose();
_disposed = true;
}
}
#endregion
}
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internal abstract class ParamsDeserializer
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{
protected IBinaryStream m_input;
protected string m_title;
protected Version m_version;
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protected ParamsDeserializer (IBinaryStream input, Version version)
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{
m_input = input;
m_version = version;
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}
public static ParamsDeserializer Create (IBinaryStream input)
{
var header = input.ReadHeader (0x11);
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if (header.AsciiEqual ("[SCR-PARAMS]v0"))
{
Version version;
if ('.' == header[15])
version = Version.Parse (header.GetCString (13, 4));
else
version = new Version (header[14] - '0', 0);
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if (2 == version.Major)
return new ParamsV2Deserializer (input, version);
else if (version.Major < 5)
return new ParamsV4Deserializer (input, version);
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else if (5 == version.Major && (version.Minor >= 4 && version.Minor <= 7))
return new ParamsV5Deserializer (input, version);
}
throw new UnknownEncryptionScheme();
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}
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public virtual LinkEncryption GetEncryption ()
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{
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return new LinkEncryption (GetKey());
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}
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public abstract byte[] GetKey ();
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protected byte[] ReadKey ()
{
int key_length = m_input.ReadInt32();
return m_input.ReadBytes (key_length);
}
protected virtual string ReadString ()
{
int length = m_input.ReadUInt8();
return m_input.ReadCString (length);
}
protected virtual void SkipString ()
{
SkipChunk();
}
protected void Skip (int amount)
{
m_input.Seek (amount, SeekOrigin.Current);
}
protected void SkipChunk ()
{
Skip (m_input.ReadUInt8());
}
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protected void SkipArray ()
{
int count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
SkipChunk();
}
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protected void SkipDict ()
{
int count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
{
SkipString();
SkipString();
}
}
protected void ReadHeader (int start)
{
m_input.Position = start;
SkipChunk();
m_title = ReadString();
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if (m_version.Major < 2)
m_input.ReadCString();
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// else
// SkipString();
SkipString();
SkipString();
m_input.ReadByte();
SkipString();
SkipString();
SkipDict();
m_input.ReadByte();
}
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}
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internal class ParamsV2Deserializer : ParamsDeserializer
{
public ParamsV2Deserializer (IBinaryStream input, Version version) : base (input, version)
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{
}
public override LinkEncryption GetEncryption ()
{
var key = GetKey();
return new LinkEncryption (key, m_title != "幼なじみと甘~くエッチに過ごす方法");
}
public override byte[] GetKey ()
{
ReadHeader (0x17);
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if ("幼なじみと甘~くエッチに過ごす方法" == m_title || "艶女医" == m_title)
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{
int count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
{
m_input.ReadByte();
SkipChunk();
SkipArray();
SkipChunk();
}
SkipArray();
SkipArray();
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if ("幼なじみと甘~くエッチに過ごす方法" == m_title)
{
m_input.ReadInt32();
return m_input.ReadBytes (240000);
}
else
{
return ReadKey();
}
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}
else // 毎日がM!
{
int count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
{
m_input.ReadByte();
SkipChunk();
SkipArray();
SkipArray();
}
SkipDict();
count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
{
SkipChunk();
SkipArray();
SkipArray();
}
return ReadKey();
}
}
}
internal class ParamsV4Deserializer : ParamsDeserializer
{
public ParamsV4Deserializer (IBinaryStream input, Version version) : base (input, version)
{
}
public override byte[] GetKey ()
{
ReadHeader (0x19);
Skip (m_version.Major < 5 ? 12 : 11);
int count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
{
m_input.ReadByte();
SkipChunk();
SkipArray();
SkipArray();
}
SkipDict();
count = m_input.ReadUInt8();
for (int i = 0; i < count; ++i)
{
SkipChunk();
SkipArray();
SkipArray();
}
return ReadKey();
}
}
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internal class ParamsV5Deserializer : ParamsDeserializer
{
public ParamsV5Deserializer (IBinaryStream input, Version version) : base (input, version)
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{
}
public override byte[] GetKey ()
{
ReadHeader (0x1B);
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Skip (m_version.Minor <= 4 ? 15 : 16);
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for (int i = 0; i < 3; ++i)
{
if (0 != m_input.ReadUInt8())
SkipTree();
}
Skip (m_input.ReadInt32() * 0xC);
return ReadKey();
}
protected override void SkipString ()
{
int length = m_input.ReadUInt16();
Skip (length);
}
byte[] name_buffer = new byte[0x100];
protected override string ReadString ()
{
int length = m_input.ReadUInt16();
if (length > name_buffer.Length)
name_buffer = new byte[length];
m_input.Read (name_buffer, 0, length);
return Encoding.Unicode.GetString (name_buffer, 0, length);
}
protected void SkipTree ()
{
SkipString();
int count = m_input.ReadInt32();
while (count --> 0)
{
SkipString();
SkipString();
}
count = m_input.ReadInt32();
while (count --> 0)
SkipTree();
}
}
internal class LinkEncryption
{
byte[] m_key;
Tuple<string, Decryptor>[] m_type_table;
delegate Stream Decryptor (LinkArchive arc, LinkEntry entry);
static readonly ResourceInstance<AnmOpener> An00 = new ResourceInstance<AnmOpener> ("ANM/KAGUYA");
static readonly ResourceInstance<An10Opener> An10 = new ResourceInstance<An10Opener> ("AN10/KAGUYA");
static readonly ResourceInstance<An20Opener> An20 = new ResourceInstance<An20Opener> ("AN20/KAGUYA");
static readonly ResourceInstance<Pl00Opener> Pl00 = new ResourceInstance<Pl00Opener> ("PLT/KAGUYA");
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public LinkEncryption (byte[] key, bool anm_encrypted = true)
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{
if (null == key || 0 == key.Length)
throw new ArgumentException ("Invalid encryption key");
m_key = key;
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var table = new List<Tuple<string, Decryptor>>
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{
new Tuple<string, Decryptor> ("BM", (a, e) => DecryptImage (a, e, 0x36)),
new Tuple<string, Decryptor> ("AP-2", (a, e) => DecryptImage (a, e, 0x18)),
new Tuple<string, Decryptor> ("AP-3", (a, e) => DecryptImage (a, e, 0x18)),
new Tuple<string, Decryptor> ("AP", (a, e) => DecryptImage (a, e, 0xC)),
};
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if (anm_encrypted)
{
table.Add (new Tuple<string, Decryptor> ("AN00", (a, e) => DecryptAnm (a, e, An00.Value)));
table.Add (new Tuple<string, Decryptor> ("AN10", (a, e) => DecryptAnm (a, e, An10.Value)));
table.Add (new Tuple<string, Decryptor> ("AN20", (a, e) => DecryptAnm (a, e, An20.Value)));
table.Add (new Tuple<string, Decryptor> ("AN21", (a, e) => DecryptAn21 (a, e)));
table.Add (new Tuple<string, Decryptor> ("PL00", (a, e) => DecryptAnm (a, e, Pl00.Value)));
table.Add (new Tuple<string, Decryptor> ("PL10", (a, e) => DecryptPl10 (a, e)));
}
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m_type_table = table.ToArray();
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}
public Stream DecryptEntry (LinkArchive arc, LinkEntry entry)
{
var header = arc.File.View.ReadBytes (entry.Offset, 4);
foreach (var type in m_type_table)
{
if (header.AsciiEqual (type.Item1))
return type.Item2 (arc, entry);
}
return arc.File.CreateStream (entry.Offset, entry.Size);
}
Stream DecryptImage (LinkArchive arc, LinkEntry entry, uint data_offset)
{
var header = arc.File.View.ReadBytes (entry.Offset, data_offset);
Stream body = arc.File.CreateStream (entry.Offset+data_offset, entry.Size-data_offset);
body = new ByteStringEncryptedStream (body, m_key);
return new PrefixStream (header, body);
}
Stream DecryptAnm (LinkArchive arc, LinkEntry entry, IAnmReader reader)
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{
var data = arc.File.View.ReadBytes (entry.Offset, entry.Size);
var input = new BinMemoryStream (data, entry.Name);
var dir = reader.GetFramesList (input);
if (dir != null)
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{
foreach (AnmEntry frame in dir)
{
DecryptData (data, (int)frame.ImageDataOffset, (int)frame.ImageDataSize);
}
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}
input.Position = 0;
return input;
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}
Stream DecryptAn21 (LinkArchive arc, LinkEntry entry)
{
var data = arc.File.View.ReadBytes (entry.Offset, entry.Size);
int count = data.ToUInt16 (4);
int offset = 8;
for (int i = 0; i < count; ++i)
{
switch (data[offset++])
{
case 0: break;
case 1: offset += 8; break;
case 2:
case 3:
case 4:
case 5: offset += 4; break;
default: return new BinMemoryStream (data, entry.Name);
}
}
count = data.ToUInt16 (offset);
offset += 2 + count * 8 + 0x21;
int w = data.ToInt32 (offset);
int h = data.ToInt32 (offset+4);
int channels = data.ToInt32 (offset+8);
offset += 12;
DecryptData (data, offset, channels * w * h);
return new BinMemoryStream (data, entry.Name);
}
Stream DecryptPl10 (LinkArchive arc, LinkEntry entry)
{
var data = arc.File.View.ReadBytes (entry.Offset, entry.Size);
int offset = 30;
int w = data.ToInt32 (offset);
int h = data.ToInt32 (offset+4);
int channels = data.ToInt32 (offset+8);
offset += 12;
DecryptData (data, offset, channels * w * h);
return new BinMemoryStream (data, entry.Name);
}
2016-10-22 18:22:14 +08:00
void DecryptData (byte[] data, int index, int length)
{
while (length > 0)
{
int count = Math.Min (length, m_key.Length);
for (int i = 0; i < count; ++i)
{
data[index++] ^= m_key[i];
}
length -= count;
}
}
}
}