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 /* see bearssl_block.h */ 28 void 29 br_aes_ct_cbcenc_init(br_aes_ct_cbcenc_keys *ctx, 30 const void *key, size_t len) 31 { 32 ctx->vtable = &br_aes_ct_cbcenc_vtable; 33 ctx->num_rounds = br_aes_ct_keysched(ctx->skey, key, len); 34 } 35 36 /* see bearssl_block.h */ 37 void 38 br_aes_ct_cbcenc_run(const br_aes_ct_cbcenc_keys *ctx, 39 void *iv, void *data, size_t len) 40 { 41 unsigned char *buf, *ivbuf; 42 uint32_t q[8]; 43 uint32_t iv0, iv1, iv2, iv3; 44 uint32_t sk_exp[120]; 45 46 q[1] = 0; 47 q[3] = 0; 48 q[5] = 0; 49 q[7] = 0; 50 br_aes_ct_skey_expand(sk_exp, ctx->num_rounds, ctx->skey); 51 ivbuf = iv; 52 iv0 = br_dec32le(ivbuf); 53 iv1 = br_dec32le(ivbuf + 4); 54 iv2 = br_dec32le(ivbuf + 8); 55 iv3 = br_dec32le(ivbuf + 12); 56 buf = data; 57 while (len > 0) { 58 q[0] = iv0 ^ br_dec32le(buf); 59 q[2] = iv1 ^ br_dec32le(buf + 4); 60 q[4] = iv2 ^ br_dec32le(buf + 8); 61 q[6] = iv3 ^ br_dec32le(buf + 12); 62 br_aes_ct_ortho(q); 63 br_aes_ct_bitslice_encrypt(ctx->num_rounds, sk_exp, q); 64 br_aes_ct_ortho(q); 65 iv0 = q[0]; 66 iv1 = q[2]; 67 iv2 = q[4]; 68 iv3 = q[6]; 69 br_enc32le(buf, iv0); 70 br_enc32le(buf + 4, iv1); 71 br_enc32le(buf + 8, iv2); 72 br_enc32le(buf + 12, iv3); 73 buf += 16; 74 len -= 16; 75 } 76 br_enc32le(ivbuf, iv0); 77 br_enc32le(ivbuf + 4, iv1); 78 br_enc32le(ivbuf + 8, iv2); 79 br_enc32le(ivbuf + 12, iv3); 80 } 81 82 /* see bearssl_block.h */ 83 const br_block_cbcenc_class br_aes_ct_cbcenc_vtable = { 84 sizeof(br_aes_ct_cbcenc_keys), 85 16, 86 4, 87 (void (*)(const br_block_cbcenc_class **, const void *, size_t)) 88 &br_aes_ct_cbcenc_init, 89 (void (*)(const br_block_cbcenc_class *const *, void *, void *, size_t)) 90 &br_aes_ct_cbcenc_run 91 }; 92