diff options
| -rw-r--r-- | src/add_developedtweakey/tweakey.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/src/add_developedtweakey/tweakey.c b/src/add_developedtweakey/tweakey.c index 98484bc..a602191 100644 --- a/src/add_developedtweakey/tweakey.c +++ b/src/add_developedtweakey/tweakey.c @@ -53,6 +53,11 @@ static uint8_t _M2(uint8_t x) return x<<6 ^ (x & 0xf8) ^ x>>6; } +static uint8_t _M3(uint8_t x) +{ + return x & 0x1f; +} + static void _multiply_M(const uint8_t X[LANE_BYTES], uint8_t Y[LANE_BYTES]) { Y[7] = X[6]; @@ -103,9 +108,14 @@ static void _multiply_MR(const uint8_t X[LANE_BYTES], uint8_t Y[LANE_BYTES]) static void _multiply_MR2(const uint8_t X[LANE_BYTES], uint8_t Y[LANE_BYTES]) { - uint8_t MR_X[LANE_BYTES]; - _multiply_MR(X, MR_X); - _multiply_MR(MR_X, Y); + Y[0] = X[2]; + Y[1] = X[3] ^ X[4]>>3; + Y[2] = X[4] ^ X[5]>>3 ^ _M3(X[6]); + Y[3] = X[5] ^ X[6]<<3; + Y[4] = X[3]<<2 ^ X[6] ^ X[7]<<3; + Y[5] = X[4]<<2 ^ X[7]; + Y[6] = X[0]; + Y[7] = X[1]; } static void _multiply_MR3(const uint8_t X[LANE_BYTES], uint8_t Y[LANE_BYTES]) |