/*
* GOST Decryption
*/
void GOST_28147_89::decrypt_n(const byte in[], byte out[], size_t blocks) const
{
for(size_t i = 0; i != blocks; ++i)
{
u32bit N1 = load_le<u32bit>(in, 0);
u32bit N2 = load_le<u32bit>(in, 1);
GOST_2ROUND(N1, N2, 0, 1);
GOST_2ROUND(N1, N2, 2, 3);
GOST_2ROUND(N1, N2, 4, 5);
GOST_2ROUND(N1, N2, 6, 7);
for(size_t j = 0; j != 3; ++j)
{
GOST_2ROUND(N1, N2, 7, 6);
GOST_2ROUND(N1, N2, 5, 4);
GOST_2ROUND(N1, N2, 3, 2);
GOST_2ROUND(N1, N2, 1, 0);
}
store_le(out, N2, N1);
in += BLOCK_SIZE;
out += BLOCK_SIZE;
}
}
/*
* GOST Encryption
*/
void GOST_28147_89::enc(const byte in[], byte out[]) const
{
u32bit N1 = load_le<u32bit>(in, 0), N2 = load_le<u32bit>(in, 1);
for(size_t i = 0; i != 3; ++i)
{
GOST_2ROUND(N1, N2, 0, 1);
GOST_2ROUND(N1, N2, 2, 3);
GOST_2ROUND(N1, N2, 4, 5);
GOST_2ROUND(N1, N2, 6, 7);
}
GOST_2ROUND(N1, N2, 7, 6);
GOST_2ROUND(N1, N2, 5, 4);
GOST_2ROUND(N1, N2, 3, 2);
GOST_2ROUND(N1, N2, 1, 0);
store_le(out, N2, N1);
}