1*0957b409SSimon J. Gerraty /* 2*0957b409SSimon J. Gerraty * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org> 3*0957b409SSimon J. Gerraty * 4*0957b409SSimon J. Gerraty * Permission is hereby granted, free of charge, to any person obtaining 5*0957b409SSimon J. Gerraty * a copy of this software and associated documentation files (the 6*0957b409SSimon J. Gerraty * "Software"), to deal in the Software without restriction, including 7*0957b409SSimon J. Gerraty * without limitation the rights to use, copy, modify, merge, publish, 8*0957b409SSimon J. Gerraty * distribute, sublicense, and/or sell copies of the Software, and to 9*0957b409SSimon J. Gerraty * permit persons to whom the Software is furnished to do so, subject to 10*0957b409SSimon J. Gerraty * the following conditions: 11*0957b409SSimon J. Gerraty * 12*0957b409SSimon J. Gerraty * The above copyright notice and this permission notice shall be 13*0957b409SSimon J. Gerraty * included in all copies or substantial portions of the Software. 14*0957b409SSimon J. Gerraty * 15*0957b409SSimon J. Gerraty * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16*0957b409SSimon J. Gerraty * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17*0957b409SSimon J. Gerraty * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18*0957b409SSimon J. Gerraty * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 19*0957b409SSimon J. Gerraty * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20*0957b409SSimon J. Gerraty * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 21*0957b409SSimon J. Gerraty * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22*0957b409SSimon J. Gerraty * SOFTWARE. 23*0957b409SSimon J. Gerraty */ 24*0957b409SSimon J. Gerraty 25*0957b409SSimon J. Gerraty #include "inner.h" 26*0957b409SSimon J. Gerraty 27*0957b409SSimon J. Gerraty #define S br_aes_S 28*0957b409SSimon J. Gerraty 29*0957b409SSimon J. Gerraty static void 30*0957b409SSimon J. Gerraty add_round_key(unsigned *state, const uint32_t *skeys) 31*0957b409SSimon J. Gerraty { 32*0957b409SSimon J. Gerraty int i; 33*0957b409SSimon J. Gerraty 34*0957b409SSimon J. Gerraty for (i = 0; i < 16; i += 4) { 35*0957b409SSimon J. Gerraty uint32_t k; 36*0957b409SSimon J. Gerraty 37*0957b409SSimon J. Gerraty k = *skeys ++; 38*0957b409SSimon J. Gerraty state[i + 0] ^= (unsigned)(k >> 24); 39*0957b409SSimon J. Gerraty state[i + 1] ^= (unsigned)(k >> 16) & 0xFF; 40*0957b409SSimon J. Gerraty state[i + 2] ^= (unsigned)(k >> 8) & 0xFF; 41*0957b409SSimon J. Gerraty state[i + 3] ^= (unsigned)k & 0xFF; 42*0957b409SSimon J. Gerraty } 43*0957b409SSimon J. Gerraty } 44*0957b409SSimon J. Gerraty 45*0957b409SSimon J. Gerraty static void 46*0957b409SSimon J. Gerraty sub_bytes(unsigned *state) 47*0957b409SSimon J. Gerraty { 48*0957b409SSimon J. Gerraty int i; 49*0957b409SSimon J. Gerraty 50*0957b409SSimon J. Gerraty for (i = 0; i < 16; i ++) { 51*0957b409SSimon J. Gerraty state[i] = S[state[i]]; 52*0957b409SSimon J. Gerraty } 53*0957b409SSimon J. Gerraty } 54*0957b409SSimon J. Gerraty 55*0957b409SSimon J. Gerraty static void 56*0957b409SSimon J. Gerraty shift_rows(unsigned *state) 57*0957b409SSimon J. Gerraty { 58*0957b409SSimon J. Gerraty unsigned tmp; 59*0957b409SSimon J. Gerraty 60*0957b409SSimon J. Gerraty tmp = state[1]; 61*0957b409SSimon J. Gerraty state[1] = state[5]; 62*0957b409SSimon J. Gerraty state[5] = state[9]; 63*0957b409SSimon J. Gerraty state[9] = state[13]; 64*0957b409SSimon J. Gerraty state[13] = tmp; 65*0957b409SSimon J. Gerraty 66*0957b409SSimon J. Gerraty tmp = state[2]; 67*0957b409SSimon J. Gerraty state[2] = state[10]; 68*0957b409SSimon J. Gerraty state[10] = tmp; 69*0957b409SSimon J. Gerraty tmp = state[6]; 70*0957b409SSimon J. Gerraty state[6] = state[14]; 71*0957b409SSimon J. Gerraty state[14] = tmp; 72*0957b409SSimon J. Gerraty 73*0957b409SSimon J. Gerraty tmp = state[15]; 74*0957b409SSimon J. Gerraty state[15] = state[11]; 75*0957b409SSimon J. Gerraty state[11] = state[7]; 76*0957b409SSimon J. Gerraty state[7] = state[3]; 77*0957b409SSimon J. Gerraty state[3] = tmp; 78*0957b409SSimon J. Gerraty } 79*0957b409SSimon J. Gerraty 80*0957b409SSimon J. Gerraty static void 81*0957b409SSimon J. Gerraty mix_columns(unsigned *state) 82*0957b409SSimon J. Gerraty { 83*0957b409SSimon J. Gerraty int i; 84*0957b409SSimon J. Gerraty 85*0957b409SSimon J. Gerraty for (i = 0; i < 16; i += 4) { 86*0957b409SSimon J. Gerraty unsigned s0, s1, s2, s3; 87*0957b409SSimon J. Gerraty unsigned t0, t1, t2, t3; 88*0957b409SSimon J. Gerraty 89*0957b409SSimon J. Gerraty s0 = state[i + 0]; 90*0957b409SSimon J. Gerraty s1 = state[i + 1]; 91*0957b409SSimon J. Gerraty s2 = state[i + 2]; 92*0957b409SSimon J. Gerraty s3 = state[i + 3]; 93*0957b409SSimon J. Gerraty t0 = (s0 << 1) ^ s1 ^ (s1 << 1) ^ s2 ^ s3; 94*0957b409SSimon J. Gerraty t1 = s0 ^ (s1 << 1) ^ s2 ^ (s2 << 1) ^ s3; 95*0957b409SSimon J. Gerraty t2 = s0 ^ s1 ^ (s2 << 1) ^ s3 ^ (s3 << 1); 96*0957b409SSimon J. Gerraty t3 = s0 ^ (s0 << 1) ^ s1 ^ s2 ^ (s3 << 1); 97*0957b409SSimon J. Gerraty state[i + 0] = t0 ^ ((unsigned)(-(int)(t0 >> 8)) & 0x11B); 98*0957b409SSimon J. Gerraty state[i + 1] = t1 ^ ((unsigned)(-(int)(t1 >> 8)) & 0x11B); 99*0957b409SSimon J. Gerraty state[i + 2] = t2 ^ ((unsigned)(-(int)(t2 >> 8)) & 0x11B); 100*0957b409SSimon J. Gerraty state[i + 3] = t3 ^ ((unsigned)(-(int)(t3 >> 8)) & 0x11B); 101*0957b409SSimon J. Gerraty } 102*0957b409SSimon J. Gerraty } 103*0957b409SSimon J. Gerraty 104*0957b409SSimon J. Gerraty /* see inner.h */ 105*0957b409SSimon J. Gerraty void 106*0957b409SSimon J. Gerraty br_aes_small_encrypt(unsigned num_rounds, const uint32_t *skey, void *data) 107*0957b409SSimon J. Gerraty { 108*0957b409SSimon J. Gerraty unsigned char *buf; 109*0957b409SSimon J. Gerraty unsigned state[16]; 110*0957b409SSimon J. Gerraty unsigned u; 111*0957b409SSimon J. Gerraty 112*0957b409SSimon J. Gerraty buf = data; 113*0957b409SSimon J. Gerraty for (u = 0; u < 16; u ++) { 114*0957b409SSimon J. Gerraty state[u] = buf[u]; 115*0957b409SSimon J. Gerraty } 116*0957b409SSimon J. Gerraty add_round_key(state, skey); 117*0957b409SSimon J. Gerraty for (u = 1; u < num_rounds; u ++) { 118*0957b409SSimon J. Gerraty sub_bytes(state); 119*0957b409SSimon J. Gerraty shift_rows(state); 120*0957b409SSimon J. Gerraty mix_columns(state); 121*0957b409SSimon J. Gerraty add_round_key(state, skey + (u << 2)); 122*0957b409SSimon J. Gerraty } 123*0957b409SSimon J. Gerraty sub_bytes(state); 124*0957b409SSimon J. Gerraty shift_rows(state); 125*0957b409SSimon J. Gerraty add_round_key(state, skey + (num_rounds << 2)); 126*0957b409SSimon J. Gerraty for (u = 0; u < 16; u ++) { 127*0957b409SSimon J. Gerraty buf[u] = state[u]; 128*0957b409SSimon J. Gerraty } 129*0957b409SSimon J. Gerraty } 130