diff options
Diffstat (limited to 'third_party/bearssl/src/aes_ct_enc.c')
| -rw-r--r-- | third_party/bearssl/src/aes_ct_enc.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/third_party/bearssl/src/aes_ct_enc.c b/third_party/bearssl/src/aes_ct_enc.c new file mode 100644 index 0000000..089bf35 --- /dev/null +++ b/third_party/bearssl/src/aes_ct_enc.c @@ -0,0 +1,112 @@ +/* + * Copyright (c) 2016 Thomas Pornin <[email protected]> + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "inner.h" + +static inline void +add_round_key(uint32_t *q, const uint32_t *sk) +{ + q[0] ^= sk[0]; + q[1] ^= sk[1]; + q[2] ^= sk[2]; + q[3] ^= sk[3]; + q[4] ^= sk[4]; + q[5] ^= sk[5]; + q[6] ^= sk[6]; + q[7] ^= sk[7]; +} + +static inline void +shift_rows(uint32_t *q) +{ + int i; + + for (i = 0; i < 8; i ++) { + uint32_t x; + + x = q[i]; + q[i] = (x & 0x000000FF) + | ((x & 0x0000FC00) >> 2) | ((x & 0x00000300) << 6) + | ((x & 0x00F00000) >> 4) | ((x & 0x000F0000) << 4) + | ((x & 0xC0000000) >> 6) | ((x & 0x3F000000) << 2); + } +} + +static inline uint32_t +rotr16(uint32_t x) +{ + return (x << 16) | (x >> 16); +} + +static inline void +mix_columns(uint32_t *q) +{ + uint32_t q0, q1, q2, q3, q4, q5, q6, q7; + uint32_t r0, r1, r2, r3, r4, r5, r6, r7; + + q0 = q[0]; + q1 = q[1]; + q2 = q[2]; + q3 = q[3]; + q4 = q[4]; + q5 = q[5]; + q6 = q[6]; + q7 = q[7]; + r0 = (q0 >> 8) | (q0 << 24); + r1 = (q1 >> 8) | (q1 << 24); + r2 = (q2 >> 8) | (q2 << 24); + r3 = (q3 >> 8) | (q3 << 24); + r4 = (q4 >> 8) | (q4 << 24); + r5 = (q5 >> 8) | (q5 << 24); + r6 = (q6 >> 8) | (q6 << 24); + r7 = (q7 >> 8) | (q7 << 24); + + q[0] = q7 ^ r7 ^ r0 ^ rotr16(q0 ^ r0); + q[1] = q0 ^ r0 ^ q7 ^ r7 ^ r1 ^ rotr16(q1 ^ r1); + q[2] = q1 ^ r1 ^ r2 ^ rotr16(q2 ^ r2); + q[3] = q2 ^ r2 ^ q7 ^ r7 ^ r3 ^ rotr16(q3 ^ r3); + q[4] = q3 ^ r3 ^ q7 ^ r7 ^ r4 ^ rotr16(q4 ^ r4); + q[5] = q4 ^ r4 ^ r5 ^ rotr16(q5 ^ r5); + q[6] = q5 ^ r5 ^ r6 ^ rotr16(q6 ^ r6); + q[7] = q6 ^ r6 ^ r7 ^ rotr16(q7 ^ r7); +} + +/* see inner.h */ +void +br_aes_ct_bitslice_encrypt(unsigned num_rounds, + const uint32_t *skey, uint32_t *q) +{ + unsigned u; + + add_round_key(q, skey); + for (u = 1; u < num_rounds; u ++) { + br_aes_ct_bitslice_Sbox(q); + shift_rows(q); + mix_columns(q); + add_round_key(q, skey + (u << 3)); + } + br_aes_ct_bitslice_Sbox(q); + shift_rows(q); + add_round_key(q, skey + (num_rounds << 3)); +} |