1 /* 2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org> 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining 5 * a copy of this software and associated documentation files (the 6 * "Software"), to deal in the Software without restriction, including 7 * without limitation the rights to use, copy, modify, merge, publish, 8 * distribute, sublicense, and/or sell copies of the Software, and to 9 * permit persons to whom the Software is furnished to do so, subject to 10 * the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be 13 * included in all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 * SOFTWARE. 23 */ 24 25 #include "inner.h" 26 27 static inline void 28 add_round_key(uint32_t *q, const uint32_t *sk) 29 { 30 q[0] ^= sk[0]; 31 q[1] ^= sk[1]; 32 q[2] ^= sk[2]; 33 q[3] ^= sk[3]; 34 q[4] ^= sk[4]; 35 q[5] ^= sk[5]; 36 q[6] ^= sk[6]; 37 q[7] ^= sk[7]; 38 } 39 40 static inline void 41 shift_rows(uint32_t *q) 42 { 43 int i; 44 45 for (i = 0; i < 8; i ++) { 46 uint32_t x; 47 48 x = q[i]; 49 q[i] = (x & 0x000000FF) 50 | ((x & 0x0000FC00) >> 2) | ((x & 0x00000300) << 6) 51 | ((x & 0x00F00000) >> 4) | ((x & 0x000F0000) << 4) 52 | ((x & 0xC0000000) >> 6) | ((x & 0x3F000000) << 2); 53 } 54 } 55 56 static inline uint32_t 57 rotr16(uint32_t x) 58 { 59 return (x << 16) | (x >> 16); 60 } 61 62 static inline void 63 mix_columns(uint32_t *q) 64 { 65 uint32_t q0, q1, q2, q3, q4, q5, q6, q7; 66 uint32_t r0, r1, r2, r3, r4, r5, r6, r7; 67 68 q0 = q[0]; 69 q1 = q[1]; 70 q2 = q[2]; 71 q3 = q[3]; 72 q4 = q[4]; 73 q5 = q[5]; 74 q6 = q[6]; 75 q7 = q[7]; 76 r0 = (q0 >> 8) | (q0 << 24); 77 r1 = (q1 >> 8) | (q1 << 24); 78 r2 = (q2 >> 8) | (q2 << 24); 79 r3 = (q3 >> 8) | (q3 << 24); 80 r4 = (q4 >> 8) | (q4 << 24); 81 r5 = (q5 >> 8) | (q5 << 24); 82 r6 = (q6 >> 8) | (q6 << 24); 83 r7 = (q7 >> 8) | (q7 << 24); 84 85 q[0] = q7 ^ r7 ^ r0 ^ rotr16(q0 ^ r0); 86 q[1] = q0 ^ r0 ^ q7 ^ r7 ^ r1 ^ rotr16(q1 ^ r1); 87 q[2] = q1 ^ r1 ^ r2 ^ rotr16(q2 ^ r2); 88 q[3] = q2 ^ r2 ^ q7 ^ r7 ^ r3 ^ rotr16(q3 ^ r3); 89 q[4] = q3 ^ r3 ^ q7 ^ r7 ^ r4 ^ rotr16(q4 ^ r4); 90 q[5] = q4 ^ r4 ^ r5 ^ rotr16(q5 ^ r5); 91 q[6] = q5 ^ r5 ^ r6 ^ rotr16(q6 ^ r6); 92 q[7] = q6 ^ r6 ^ r7 ^ rotr16(q7 ^ r7); 93 } 94 95 /* see inner.h */ 96 void 97 br_aes_ct_bitslice_encrypt(unsigned num_rounds, 98 const uint32_t *skey, uint32_t *q) 99 { 100 unsigned u; 101 102 add_round_key(q, skey); 103 for (u = 1; u < num_rounds; u ++) { 104 br_aes_ct_bitslice_Sbox(q); 105 shift_rows(q); 106 mix_columns(q); 107 add_round_key(q, skey + (u << 3)); 108 } 109 br_aes_ct_bitslice_Sbox(q); 110 shift_rows(q); 111 add_round_key(q, skey + (num_rounds << 3)); 112 } 113