diff options
| -rw-r--r-- | aes.c | 35 |
1 files changed, 17 insertions, 18 deletions
@@ -412,23 +412,23 @@ static void Cipher(state_t* state, const uint8_t* RoundKey) uint8_t round = 0; // Add the First round key to the state before starting the rounds. - AddRoundKey(0, state, RoundKey); - + AddRoundKey(0, state, RoundKey); + // There will be Nr rounds. // The first Nr-1 rounds are identical. - // These Nr-1 rounds are executed in the loop below. - for (round = 1; round < Nr; ++round) + // These Nr rounds are executed in the loop below. + // Last one without MixColumns() + for (round = 1; ; ++round) { SubBytes(state); ShiftRows(state); + if (round == Nr) { + break; + } MixColumns(state); AddRoundKey(round, state, RoundKey); } - - // The last round is given below. - // The MixColumns function is not here in the last round. - SubBytes(state); - ShiftRows(state); + // Add round key to last round AddRoundKey(Nr, state, RoundKey); } @@ -438,24 +438,23 @@ static void InvCipher(state_t* state, const uint8_t* RoundKey) uint8_t round = 0; // Add the First round key to the state before starting the rounds. - AddRoundKey(Nr, state, RoundKey); + AddRoundKey(Nr, state, RoundKey); // There will be Nr rounds. // The first Nr-1 rounds are identical. - // These Nr-1 rounds are executed in the loop below. - for (round = (Nr - 1); round > 0; --round) + // These Nr rounds are executed in the loop below. + // Last one without InvMixColumn() + for (round = (Nr - 1); ; --round) { InvShiftRows(state); InvSubBytes(state); AddRoundKey(round, state, RoundKey); + if (round == 0) { + break; + } InvMixColumns(state); } - - // The last round is given below. - // The MixColumns function is not here in the last round. - InvShiftRows(state); - InvSubBytes(state); - AddRoundKey(0, state, RoundKey); + } #endif // #if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1) |