Public-Mirror/GARbro-mirror
1
0
Fork 0
mirror of https://github.com/crskycode/GARbro.git synced 2024-12-23 19:34:15 +08:00
Code Issues Projects Releases Wiki Activity

(XP3): added optional AES decryption.

Browse Source
This commit is contained in:
morkt 2017-09-27 15:42:53 +04:00
parent 99ab258678
commit b713a01031
1 changed files with 82 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

82
ArcFormats/KiriKiri/ArcXP3.cs
View File

@ -354,6 +354,10 @@ NextEntry:
// assume no scripts are compressed using LZ4, return decompressed stream right away
return DecompressLz4 (xp3_entry, header, input);
}
else if (0xA590D7FD == header.ToUInt32 (0)) // cZLIB magic
{
return DecompressCz (xp3_entry, header, input);
}
if (0xFE == header[0] && 0xFE == header[1] && header[2] < 3 && 0xFF == header[3] && 0xFE == header[4])
return DecryptScript (header[2], input, xp3_entry.UnpackedSize);
@ -389,6 +393,84 @@ NextEntry:
return new Lz4Stream (input, info);
}
Stream DecompressCz (Xp3Entry entry, byte[] src_header, Stream input)
{
var header = new byte[15];
Buffer.BlockCopy (src_header, 0, header, 0, Math.Min (header.Length, src_header.Length));
if (header.Length > src_header.Length)
input.Read (header, src_header.Length, header.Length - src_header.Length);
header[4] ^= 0x11;
header[5] ^= 0x7F;
header[6] ^= 0x9A;
byte key = header[4];
int unpacked_size = CzDecryptInt (header, 7, key);
int packed_size = CzDecryptInt (header, 11, key);
var data = new byte[packed_size];
input.Read (data, 0, packed_size);
input.Dispose();
data = CzDecryptData (data);
input = new BinMemoryStream (data);
if ('C' == header[4])
input = new ZLibStream (input, CompressionMode.Decompress);
return input;
}
static int CzDecryptInt (byte[] data, int offset, byte key)
{
for (int i = 0; i < 4; ++i)
{
data[offset+i] ^= (byte)(key ^ CzHeaderKey[i]);
}
return data.ToInt32 (offset);
}
static byte[] CzDecryptData (byte[] data)
{
int padded_size = data.Length - 5;
int original_size = padded_size - (data[padded_size+1] ^ data[padded_size]);
uint iv_seed = data.ToUInt32 (padded_size+1) ^ 0xBFBFBFBFu;
using (var aes = Aes.Create())
{
aes.Mode = CipherMode.CBC;
aes.Padding = PaddingMode.Zeros;
aes.Key = CzDefaultKey;
aes.IV = CzCreateIV (iv_seed);
using (var enc = new MemoryStream (data, 0, padded_size))
using (var dec = new InputCryptoStream (enc, aes.CreateDecryptor()))
{
var original = new byte[original_size];
dec.Read (original, 0, original_size);
return original;
}
}
}
static byte[] CzCreateIV (uint seed)
{
var state = new uint[4];
state[0] = 123456789; // field_0
state[1] = 972436830; // field_4
state[2] = 524018621; // field_8
state[3] = seed; // field_C
var iv = new byte[16];
for (int i = 0; i < 16; ++i)
{
uint a = state[3];
uint b = state[0] ^ (state[0] << 11);
state[0] = state[1];
state[1] = state[2];
state[2] = a;
state[3] = b ^ a ^ ((b ^ (a >> 11)) >> 8);
iv[i] = (byte)state[3];
}
return iv;
}
static readonly byte[] CzHeaderKey = { 0x9D, 0x1D, 0x9A, 0xF2 };
static readonly byte[] CzDefaultKey = {
0x91, 0x10, 0xFC, 0x75, 0x45, 0x8F, 0xB5, 0xE6, 0xFE, 0xAC, 0xBA, 0x44, 0x76, 0x58, 0xC2, 0x1A
};
Stream DecryptScript (int enc_type, Stream input, uint unpacked_size)
{
using (var reader = new BinaryReader (input, Encoding.Unicode, true))