Added detection for MIPS64 with n32 ABI.
[BearSSL] / src / symcipher / aes_small_ctr.c
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_small_ctr_init(br_aes_small_ctr_keys *ctx,
30 const void *key, size_t len)
31 {
32 ctx->vtable = &br_aes_small_ctr_vtable;
33 ctx->num_rounds = br_aes_keysched(ctx->skey, key, len);
34 }
35
36 static void
37 xorbuf(void *dst, const void *src, size_t len)
38 {
39 unsigned char *d;
40 const unsigned char *s;
41
42 d = dst;
43 s = src;
44 while (len -- > 0) {
45 *d ++ ^= *s ++;
46 }
47 }
48
49 /* see bearssl_block.h */
50 uint32_t
51 br_aes_small_ctr_run(const br_aes_small_ctr_keys *ctx,
52 const void *iv, uint32_t cc, void *data, size_t len)
53 {
54 unsigned char *buf;
55
56 buf = data;
57 while (len > 0) {
58 unsigned char tmp[16];
59
60 memcpy(tmp, iv, 12);
61 br_enc32be(tmp + 12, cc ++);
62 br_aes_small_encrypt(ctx->num_rounds, ctx->skey, tmp);
63 if (len <= 16) {
64 xorbuf(buf, tmp, len);
65 break;
66 }
67 xorbuf(buf, tmp, 16);
68 buf += 16;
69 len -= 16;
70 }
71 return cc;
72 }
73
74 /* see bearssl_block.h */
75 const br_block_ctr_class br_aes_small_ctr_vtable = {
76 sizeof(br_aes_small_ctr_keys),
77 16,
78 4,
79 (void (*)(const br_block_ctr_class **, const void *, size_t))
80 &br_aes_small_ctr_init,
81 (uint32_t (*)(const br_block_ctr_class *const *,
82 const void *, uint32_t, void *, size_t))
83 &br_aes_small_ctr_run
84 };