public override Stream OpenEntry(ArcFile arc, Entry entry)
{
var mca = arc as McaArchive;
int method = arc.File.View.ReadInt32(entry.Offset);
if (null == mca || method < 0 || method > 1)
{
return(base.OpenEntry(arc, entry));
}
uint width = arc.File.View.ReadUInt32(entry.Offset + 0xC);
uint height = arc.File.View.ReadUInt32(entry.Offset + 0x10);
uint packed_size = arc.File.View.ReadUInt32(entry.Offset + 0x14);
int unpacked_size = arc.File.View.ReadInt32(entry.Offset + 0x18);
var data = arc.File.View.ReadBytes(entry.Offset + 0x20, packed_size);
MrgOpener.Decrypt(data, 0, data.Length, mca.Key);
if (method > 0)
{
using (var input = new MemoryStream(data))
using (var lzss = new MrgLzssReader(input, data.Length, unpacked_size))
{
lzss.Unpack();
data = lzss.Data;
}
}
int stride = ((int)width * 3 + 3) & ~3;
var info = new ImageMetaData {
Width = width, Height = height, BPP = 24
};
return(TgaStream.Create(info, stride, data));
}
protected override ImageData GetImageData()
{
m_input.Position = 0x20;
var data = m_input.ReadBytes(m_packed_size);
MrgOpener.Decrypt(data, 0, data.Length, m_key);
if (m_compressed)
{
using (var input = new BinMemoryStream(data))
using (var lzss = new MrgLzssReader(input, data.Length, m_unpacked_size))
{
lzss.Unpack();
data = lzss.Data;
}
}
int stride = ((int)Info.Width * Info.BPP / 8 + 3) & ~3;
var format = 8 == Info.BPP ? PixelFormats.Indexed8 : PixelFormats.Bgr24;
return(ImageData.Create(Info, format, m_palette, data, stride));
}
void UnpackV101()
{
if (m_key != 0)
{
MrgOpener.Decrypt(m_input, 0, m_input.Length - 1, m_key);
}
#if DEBUG
else // bruteforce key *in debug build only*
{
var copy = new byte[m_input.Length];
for (int key = 1; key < 256; ++key)
{
Buffer.BlockCopy(m_input, 0, copy, 0, m_input.Length);
MrgOpener.Decrypt(copy, 0, copy.Length - 1, (byte)key);
using (var input = new BinMemoryStream(copy))
using (var lzss = new MrgLzssReader(input, copy.Length, Stride * m_height))
{
lzss.Unpack();
if (input.Length - input.Position <= 1)
{
Trace.WriteLine(string.Format("Found matching key {0:X2}", key), "[MCG]");
m_output = lzss.Data;
m_key = (byte)key;
return;
}
}
}
}
#endif
using (var input = new BinMemoryStream(m_input))
using (var lzss = new MrgLzssReader(input, m_input.Length, Stride * m_height))
{
lzss.Unpack();
// data remaining within input stream indicates invalid encryption key
if (input.Length - input.Position > 1)
{
m_key = 0;
}
m_output = lzss.Data;
}
}
void UnpackV101()
{
if (m_key != 0)
{
MrgOpener.Decrypt(m_input, 0, m_input.Length - 1, m_key);
}
#if DEBUG
else // bruteforce key *in debug build only*
{
for (int key = 1; key < 256; ++key)
{
var copy = m_input.Clone() as byte[];
MrgOpener.Decrypt(copy, 0, copy.Length - 1, (byte)key);
using (var input = new BinMemoryStream(copy))
using (var lzss = new MrgLzssReader(input, m_input.Length, Stride * m_height))
{
lzss.Unpack();
if (input.Length - input.Position <= 1)
{
m_output = lzss.Data;
m_key = (byte)key;
return;
}
}
}
}
#endif
using (var input = new BinMemoryStream(m_input))
using (var lzss = new MrgLzssReader(input, m_input.Length, Stride * m_height))
{
lzss.Unpack();
// data remaining within input stream indicates invalid encryption key
if (input.Length - input.Position > 1)
{
m_key = 0;
}
m_output = lzss.Data;
}
}
