public override void DecryptEntry(byte[] data, int offset, int length, QlieEntry entry)
{
var key_file = entry.KeyFile;
if (null == key_file)
{
base.DecryptEntry(data, offset, length, entry);
return;
}
// play it safe with 'unsafe' sections
if (offset < 0)
{
throw new ArgumentOutOfRangeException("offset");
}
if (length > data.Length || offset > data.Length - length)
{
throw new ArgumentOutOfRangeException("length");
}
if (length < 8)
{
return;
}
var file_name = entry.RawName;
uint hash = 0x85F532;
uint seed = 0x33F641;
for (uint i = 0; i < file_name.Length; i++)
{
hash += (i & 0xFF) * file_name[i];
seed ^= hash;
}
seed += ArcKey ^ (7 * ((uint)length & 0xFFFFFF) + (uint)length
+ hash + (hash ^ (uint)length ^ 0x8F32DCu));
seed = 9 * (seed & 0xFFFFFF);
if (GameKeyData != null)
{
seed ^= 0x453A;
}
var mt = new QlieMersenneTwister(seed);
if (key_file != null)
{
mt.XorState(key_file);
}
if (GameKeyData != null)
{
mt.XorState(GameKeyData);
}
// game code fills dword[41] table, but only the first 16 qwords are used
ulong[] table = new ulong[16];
for (int i = 0; i < table.Length; ++i)
{
table[i] = mt.Rand64();
}
// compensate for 9 discarded dwords
for (int i = 0; i < 9; ++i)
{
mt.Rand();
}
ulong hash64 = mt.Rand64();
uint t = mt.Rand() & 0xF;
unsafe
{
fixed(byte *raw_data = &data[offset])
{
ulong *data64 = (ulong *)raw_data;
int qword_length = length / 8;
for (int i = 0; i < qword_length; ++i)
{
hash64 = MMX.PAddD(hash64 ^ table[t], table[t]);
ulong d = data64[i] ^ hash64;
data64[i] = d;
hash64 = MMX.PAddB(hash64, d) ^ d;
hash64 = MMX.PAddW(MMX.PSllD(hash64, 1), d);
t++;
t &= 0xF;
}
}
}
}
private void DecryptV3(byte[] data, int offset, int length, byte[] file_name,
uint arc_hash, byte[] key_file, byte[] game_key)
{
// play it safe with 'unsafe' sections
if (offset < 0)
throw new ArgumentOutOfRangeException ("offset");
if (length > data.Length || offset > data.Length - length)
throw new ArgumentOutOfRangeException ("length");
if (length < 8)
return;
uint hash = 0x85F532;
uint seed = 0x33F641;
for (uint i = 0; i < file_name.Length; i++)
{
hash += (i & 0xFF) * file_name[i];
seed ^= hash;
}
seed += arc_hash ^ (7 * ((uint)data.Length & 0xFFFFFF) + (uint)data.Length
+ hash + (hash ^ (uint)data.Length ^ 0x8F32DCu));
seed = 9 * (seed & 0xFFFFFF);
if (game_key != null)
seed ^= 0x453A;
var mt = new QlieMersenneTwister (seed);
if (key_file != null)
mt.XorState (key_file);
if (game_key != null)
mt.XorState (game_key);
// game code fills dword[41] table, but only the first 16 qwords are used
ulong[] table = new ulong[16];
for (int i = 0; i < table.Length; ++i)
table[i] = mt.Rand64();
// compensate for 9 discarded dwords
for (int i = 0; i < 9; ++i)
mt.Rand();
ulong hash64 = mt.Rand64();
uint t = mt.Rand() & 0xF;
unsafe
{
fixed (byte* raw_data = &data[offset])
{
ulong* data64 = (ulong*)raw_data;
int qword_length = length / 8;
for (int i = 0; i < qword_length; ++i)
{
hash64 = MMX.PAddD (hash64 ^ table[t], table[t]);
ulong d = data64[i] ^ hash64;
data64[i] = d;
hash64 = MMX.PAddB (hash64, d) ^ d;
hash64 = MMX.PAddW (MMX.PSllD (hash64, 1), d);
t++;
t &= 0xF;
}
}
}
}
