xref: /freebsd/contrib/bearssl/src/symcipher/des_ct_cbcenc.c (revision 2a58b312b62f908ec92311d1bd8536dbaeb8e55b)
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_des_ct_cbcenc_init(br_des_ct_cbcenc_keys *ctx,
30 	const void *key, size_t len)
31 {
32 	ctx->vtable = &br_des_ct_cbcenc_vtable;
33 	ctx->num_rounds = br_des_ct_keysched(ctx->skey, key, len);
34 }
35 
36 /* see bearssl_block.h */
37 void
38 br_des_ct_cbcenc_run(const br_des_ct_cbcenc_keys *ctx,
39 	void *iv, void *data, size_t len)
40 {
41 	unsigned char *buf, *ivbuf;
42 	uint32_t sk_exp[288];
43 
44 	br_des_ct_skey_expand(sk_exp, ctx->num_rounds, ctx->skey);
45 	ivbuf = iv;
46 	buf = data;
47 	while (len > 0) {
48 		int i;
49 
50 		for (i = 0; i < 8; i ++) {
51 			buf[i] ^= ivbuf[i];
52 		}
53 		br_des_ct_process_block(ctx->num_rounds, sk_exp, buf);
54 		memcpy(ivbuf, buf, 8);
55 		buf += 8;
56 		len -= 8;
57 	}
58 }
59 
60 /* see bearssl_block.h */
61 const br_block_cbcenc_class br_des_ct_cbcenc_vtable = {
62 	sizeof(br_des_ct_cbcenc_keys),
63 	8,
64 	3,
65 	(void (*)(const br_block_cbcenc_class **, const void *, size_t))
66 		&br_des_ct_cbcenc_init,
67 	(void (*)(const br_block_cbcenc_class *const *, void *, void *, size_t))
68 		&br_des_ct_cbcenc_run
69 };
70