xref: /freebsd/contrib/bearssl/src/symcipher/aes_ct64_cbcenc.c (revision 2aaf9152a852aba9eb2036b95f4948ee77988826)
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
br_aes_ct64_cbcenc_init(br_aes_ct64_cbcenc_keys * ctx,const void * key,size_t len)29 br_aes_ct64_cbcenc_init(br_aes_ct64_cbcenc_keys *ctx,
30 	const void *key, size_t len)
31 {
32 	ctx->vtable = &br_aes_ct64_cbcenc_vtable;
33 	ctx->num_rounds = br_aes_ct64_keysched(ctx->skey, key, len);
34 }
35 
36 /* see bearssl_block.h */
37 void
br_aes_ct64_cbcenc_run(const br_aes_ct64_cbcenc_keys * ctx,void * iv,void * data,size_t len)38 br_aes_ct64_cbcenc_run(const br_aes_ct64_cbcenc_keys *ctx,
39 	void *iv, void *data, size_t len)
40 {
41 	unsigned char *buf;
42 	uint64_t sk_exp[120];
43 	uint32_t ivw[4];
44 
45 	br_aes_ct64_skey_expand(sk_exp, ctx->num_rounds, ctx->skey);
46 	br_range_dec32le(ivw, 4, iv);
47 	buf = data;
48 	while (len > 0) {
49 		uint32_t w[4];
50 		uint64_t q[8];
51 
52 		w[0] = ivw[0] ^ br_dec32le(buf);
53 		w[1] = ivw[1] ^ br_dec32le(buf + 4);
54 		w[2] = ivw[2] ^ br_dec32le(buf + 8);
55 		w[3] = ivw[3] ^ br_dec32le(buf + 12);
56 		br_aes_ct64_interleave_in(&q[0], &q[4], w);
57 		br_aes_ct64_ortho(q);
58 		br_aes_ct64_bitslice_encrypt(ctx->num_rounds, sk_exp, q);
59 		br_aes_ct64_ortho(q);
60 		br_aes_ct64_interleave_out(w, q[0], q[4]);
61 		memcpy(ivw, w, sizeof w);
62 		br_enc32le(buf, w[0]);
63 		br_enc32le(buf + 4, w[1]);
64 		br_enc32le(buf + 8, w[2]);
65 		br_enc32le(buf + 12, w[3]);
66 		buf += 16;
67 		len -= 16;
68 	}
69 	br_range_enc32le(iv, ivw, 4);
70 }
71 
72 /* see bearssl_block.h */
73 const br_block_cbcenc_class br_aes_ct64_cbcenc_vtable = {
74 	sizeof(br_aes_ct64_cbcenc_keys),
75 	16,
76 	4,
77 	(void (*)(const br_block_cbcenc_class **, const void *, size_t))
78 		&br_aes_ct64_cbcenc_init,
79 	(void (*)(const br_block_cbcenc_class *const *, void *, void *, size_t))
80 		&br_aes_ct64_cbcenc_run
81 };
82