xref: /freebsd/contrib/bearssl/src/symcipher/aes_ct64_ctr.c (revision 2aaf9152a852aba9eb2036b95f4948ee77988826)
1*0957b409SSimon J. Gerraty /*
2*0957b409SSimon J. Gerraty  * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
3*0957b409SSimon J. Gerraty  *
4*0957b409SSimon J. Gerraty  * Permission is hereby granted, free of charge, to any person obtaining
5*0957b409SSimon J. Gerraty  * a copy of this software and associated documentation files (the
6*0957b409SSimon J. Gerraty  * "Software"), to deal in the Software without restriction, including
7*0957b409SSimon J. Gerraty  * without limitation the rights to use, copy, modify, merge, publish,
8*0957b409SSimon J. Gerraty  * distribute, sublicense, and/or sell copies of the Software, and to
9*0957b409SSimon J. Gerraty  * permit persons to whom the Software is furnished to do so, subject to
10*0957b409SSimon J. Gerraty  * the following conditions:
11*0957b409SSimon J. Gerraty  *
12*0957b409SSimon J. Gerraty  * The above copyright notice and this permission notice shall be
13*0957b409SSimon J. Gerraty  * included in all copies or substantial portions of the Software.
14*0957b409SSimon J. Gerraty  *
15*0957b409SSimon J. Gerraty  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*0957b409SSimon J. Gerraty  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*0957b409SSimon J. Gerraty  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18*0957b409SSimon J. Gerraty  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19*0957b409SSimon J. Gerraty  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20*0957b409SSimon J. Gerraty  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21*0957b409SSimon J. Gerraty  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22*0957b409SSimon J. Gerraty  * SOFTWARE.
23*0957b409SSimon J. Gerraty  */
24*0957b409SSimon J. Gerraty 
25*0957b409SSimon J. Gerraty #include "inner.h"
26*0957b409SSimon J. Gerraty 
27*0957b409SSimon J. Gerraty /* see bearssl_block.h */
28*0957b409SSimon J. Gerraty void
br_aes_ct64_ctr_init(br_aes_ct64_ctr_keys * ctx,const void * key,size_t len)29*0957b409SSimon J. Gerraty br_aes_ct64_ctr_init(br_aes_ct64_ctr_keys *ctx,
30*0957b409SSimon J. Gerraty 	const void *key, size_t len)
31*0957b409SSimon J. Gerraty {
32*0957b409SSimon J. Gerraty 	ctx->vtable = &br_aes_ct64_ctr_vtable;
33*0957b409SSimon J. Gerraty 	ctx->num_rounds = br_aes_ct64_keysched(ctx->skey, key, len);
34*0957b409SSimon J. Gerraty }
35*0957b409SSimon J. Gerraty 
36*0957b409SSimon J. Gerraty static void
xorbuf(void * dst,const void * src,size_t len)37*0957b409SSimon J. Gerraty xorbuf(void *dst, const void *src, size_t len)
38*0957b409SSimon J. Gerraty {
39*0957b409SSimon J. Gerraty 	unsigned char *d;
40*0957b409SSimon J. Gerraty 	const unsigned char *s;
41*0957b409SSimon J. Gerraty 
42*0957b409SSimon J. Gerraty 	d = dst;
43*0957b409SSimon J. Gerraty 	s = src;
44*0957b409SSimon J. Gerraty 	while (len -- > 0) {
45*0957b409SSimon J. Gerraty 		*d ++ ^= *s ++;
46*0957b409SSimon J. Gerraty 	}
47*0957b409SSimon J. Gerraty }
48*0957b409SSimon J. Gerraty 
49*0957b409SSimon J. Gerraty /* see bearssl_block.h */
50*0957b409SSimon J. Gerraty uint32_t
br_aes_ct64_ctr_run(const br_aes_ct64_ctr_keys * ctx,const void * iv,uint32_t cc,void * data,size_t len)51*0957b409SSimon J. Gerraty br_aes_ct64_ctr_run(const br_aes_ct64_ctr_keys *ctx,
52*0957b409SSimon J. Gerraty 	const void *iv, uint32_t cc, void *data, size_t len)
53*0957b409SSimon J. Gerraty {
54*0957b409SSimon J. Gerraty 	unsigned char *buf;
55*0957b409SSimon J. Gerraty 	uint32_t ivw[16];
56*0957b409SSimon J. Gerraty 	uint64_t sk_exp[120];
57*0957b409SSimon J. Gerraty 
58*0957b409SSimon J. Gerraty 	br_aes_ct64_skey_expand(sk_exp, ctx->num_rounds, ctx->skey);
59*0957b409SSimon J. Gerraty 	br_range_dec32le(ivw, 3, iv);
60*0957b409SSimon J. Gerraty 	memcpy(ivw + 4, ivw, 3 * sizeof(uint32_t));
61*0957b409SSimon J. Gerraty 	memcpy(ivw + 8, ivw, 3 * sizeof(uint32_t));
62*0957b409SSimon J. Gerraty 	memcpy(ivw + 12, ivw, 3 * sizeof(uint32_t));
63*0957b409SSimon J. Gerraty 	buf = data;
64*0957b409SSimon J. Gerraty 	while (len > 0) {
65*0957b409SSimon J. Gerraty 		uint64_t q[8];
66*0957b409SSimon J. Gerraty 		uint32_t w[16];
67*0957b409SSimon J. Gerraty 		unsigned char tmp[64];
68*0957b409SSimon J. Gerraty 		int i;
69*0957b409SSimon J. Gerraty 
70*0957b409SSimon J. Gerraty 		/*
71*0957b409SSimon J. Gerraty 		 * TODO: see if we can save on the first br_aes_ct64_ortho()
72*0957b409SSimon J. Gerraty 		 * call, since iv0/iv1/iv2 are constant for the whole run.
73*0957b409SSimon J. Gerraty 		 */
74*0957b409SSimon J. Gerraty 		memcpy(w, ivw, sizeof ivw);
75*0957b409SSimon J. Gerraty 		w[3] = br_swap32(cc);
76*0957b409SSimon J. Gerraty 		w[7] = br_swap32(cc + 1);
77*0957b409SSimon J. Gerraty 		w[11] = br_swap32(cc + 2);
78*0957b409SSimon J. Gerraty 		w[15] = br_swap32(cc + 3);
79*0957b409SSimon J. Gerraty 		for (i = 0; i < 4; i ++) {
80*0957b409SSimon J. Gerraty 			br_aes_ct64_interleave_in(
81*0957b409SSimon J. Gerraty 				&q[i], &q[i + 4], w + (i << 2));
82*0957b409SSimon J. Gerraty 		}
83*0957b409SSimon J. Gerraty 		br_aes_ct64_ortho(q);
84*0957b409SSimon J. Gerraty 		br_aes_ct64_bitslice_encrypt(ctx->num_rounds, sk_exp, q);
85*0957b409SSimon J. Gerraty 		br_aes_ct64_ortho(q);
86*0957b409SSimon J. Gerraty 		for (i = 0; i < 4; i ++) {
87*0957b409SSimon J. Gerraty 			br_aes_ct64_interleave_out(
88*0957b409SSimon J. Gerraty 				w + (i << 2), q[i], q[i + 4]);
89*0957b409SSimon J. Gerraty 		}
90*0957b409SSimon J. Gerraty 		br_range_enc32le(tmp, w, 16);
91*0957b409SSimon J. Gerraty 		if (len <= 64) {
92*0957b409SSimon J. Gerraty 			xorbuf(buf, tmp, len);
93*0957b409SSimon J. Gerraty 			cc += (uint32_t)len >> 4;
94*0957b409SSimon J. Gerraty 			break;
95*0957b409SSimon J. Gerraty 		}
96*0957b409SSimon J. Gerraty 		xorbuf(buf, tmp, 64);
97*0957b409SSimon J. Gerraty 		buf += 64;
98*0957b409SSimon J. Gerraty 		len -= 64;
99*0957b409SSimon J. Gerraty 		cc += 4;
100*0957b409SSimon J. Gerraty 	}
101*0957b409SSimon J. Gerraty 	return cc;
102*0957b409SSimon J. Gerraty }
103*0957b409SSimon J. Gerraty 
104*0957b409SSimon J. Gerraty /* see bearssl_block.h */
105*0957b409SSimon J. Gerraty const br_block_ctr_class br_aes_ct64_ctr_vtable = {
106*0957b409SSimon J. Gerraty 	sizeof(br_aes_ct64_ctr_keys),
107*0957b409SSimon J. Gerraty 	16,
108*0957b409SSimon J. Gerraty 	4,
109*0957b409SSimon J. Gerraty 	(void (*)(const br_block_ctr_class **, const void *, size_t))
110*0957b409SSimon J. Gerraty 		&br_aes_ct64_ctr_init,
111*0957b409SSimon J. Gerraty 	(uint32_t (*)(const br_block_ctr_class *const *,
112*0957b409SSimon J. Gerraty 		const void *, uint32_t, void *, size_t))
113*0957b409SSimon J. Gerraty 		&br_aes_ct64_ctr_run
114*0957b409SSimon J. Gerraty };
115