1*0957b409SSimon J. Gerraty /*
2*0957b409SSimon J. Gerraty * Copyright (c) 2017 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_small_ctrcbc_init(br_aes_small_ctrcbc_keys * ctx,const void * key,size_t len)29*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_init(br_aes_small_ctrcbc_keys *ctx,
30*0957b409SSimon J. Gerraty const void *key, size_t len)
31*0957b409SSimon J. Gerraty {
32*0957b409SSimon J. Gerraty ctx->vtable = &br_aes_small_ctrcbc_vtable;
33*0957b409SSimon J. Gerraty ctx->num_rounds = br_aes_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 void
br_aes_small_ctrcbc_ctr(const br_aes_small_ctrcbc_keys * ctx,void * ctr,void * data,size_t len)51*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_ctr(const br_aes_small_ctrcbc_keys *ctx,
52*0957b409SSimon J. Gerraty void *ctr, void *data, size_t len)
53*0957b409SSimon J. Gerraty {
54*0957b409SSimon J. Gerraty unsigned char *buf, *bctr;
55*0957b409SSimon J. Gerraty uint32_t cc0, cc1, cc2, cc3;
56*0957b409SSimon J. Gerraty
57*0957b409SSimon J. Gerraty buf = data;
58*0957b409SSimon J. Gerraty bctr = ctr;
59*0957b409SSimon J. Gerraty cc3 = br_dec32be(bctr + 0);
60*0957b409SSimon J. Gerraty cc2 = br_dec32be(bctr + 4);
61*0957b409SSimon J. Gerraty cc1 = br_dec32be(bctr + 8);
62*0957b409SSimon J. Gerraty cc0 = br_dec32be(bctr + 12);
63*0957b409SSimon J. Gerraty while (len > 0) {
64*0957b409SSimon J. Gerraty unsigned char tmp[16];
65*0957b409SSimon J. Gerraty uint32_t carry;
66*0957b409SSimon J. Gerraty
67*0957b409SSimon J. Gerraty br_enc32be(tmp + 0, cc3);
68*0957b409SSimon J. Gerraty br_enc32be(tmp + 4, cc2);
69*0957b409SSimon J. Gerraty br_enc32be(tmp + 8, cc1);
70*0957b409SSimon J. Gerraty br_enc32be(tmp + 12, cc0);
71*0957b409SSimon J. Gerraty br_aes_small_encrypt(ctx->num_rounds, ctx->skey, tmp);
72*0957b409SSimon J. Gerraty xorbuf(buf, tmp, 16);
73*0957b409SSimon J. Gerraty buf += 16;
74*0957b409SSimon J. Gerraty len -= 16;
75*0957b409SSimon J. Gerraty cc0 ++;
76*0957b409SSimon J. Gerraty carry = (~(cc0 | -cc0)) >> 31;
77*0957b409SSimon J. Gerraty cc1 += carry;
78*0957b409SSimon J. Gerraty carry &= (~(cc1 | -cc1)) >> 31;
79*0957b409SSimon J. Gerraty cc2 += carry;
80*0957b409SSimon J. Gerraty carry &= (~(cc2 | -cc2)) >> 31;
81*0957b409SSimon J. Gerraty cc3 += carry;
82*0957b409SSimon J. Gerraty }
83*0957b409SSimon J. Gerraty br_enc32be(bctr + 0, cc3);
84*0957b409SSimon J. Gerraty br_enc32be(bctr + 4, cc2);
85*0957b409SSimon J. Gerraty br_enc32be(bctr + 8, cc1);
86*0957b409SSimon J. Gerraty br_enc32be(bctr + 12, cc0);
87*0957b409SSimon J. Gerraty }
88*0957b409SSimon J. Gerraty
89*0957b409SSimon J. Gerraty /* see bearssl_block.h */
90*0957b409SSimon J. Gerraty void
br_aes_small_ctrcbc_mac(const br_aes_small_ctrcbc_keys * ctx,void * cbcmac,const void * data,size_t len)91*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_mac(const br_aes_small_ctrcbc_keys *ctx,
92*0957b409SSimon J. Gerraty void *cbcmac, const void *data, size_t len)
93*0957b409SSimon J. Gerraty {
94*0957b409SSimon J. Gerraty const unsigned char *buf;
95*0957b409SSimon J. Gerraty
96*0957b409SSimon J. Gerraty buf = data;
97*0957b409SSimon J. Gerraty while (len > 0) {
98*0957b409SSimon J. Gerraty xorbuf(cbcmac, buf, 16);
99*0957b409SSimon J. Gerraty br_aes_small_encrypt(ctx->num_rounds, ctx->skey, cbcmac);
100*0957b409SSimon J. Gerraty buf += 16;
101*0957b409SSimon J. Gerraty len -= 16;
102*0957b409SSimon J. Gerraty }
103*0957b409SSimon J. Gerraty }
104*0957b409SSimon J. Gerraty
105*0957b409SSimon J. Gerraty /* see bearssl_block.h */
106*0957b409SSimon J. Gerraty void
br_aes_small_ctrcbc_encrypt(const br_aes_small_ctrcbc_keys * ctx,void * ctr,void * cbcmac,void * data,size_t len)107*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_encrypt(const br_aes_small_ctrcbc_keys *ctx,
108*0957b409SSimon J. Gerraty void *ctr, void *cbcmac, void *data, size_t len)
109*0957b409SSimon J. Gerraty {
110*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_ctr(ctx, ctr, data, len);
111*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_mac(ctx, cbcmac, data, len);
112*0957b409SSimon J. Gerraty }
113*0957b409SSimon J. Gerraty
114*0957b409SSimon J. Gerraty /* see bearssl_block.h */
115*0957b409SSimon J. Gerraty void
br_aes_small_ctrcbc_decrypt(const br_aes_small_ctrcbc_keys * ctx,void * ctr,void * cbcmac,void * data,size_t len)116*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_decrypt(const br_aes_small_ctrcbc_keys *ctx,
117*0957b409SSimon J. Gerraty void *ctr, void *cbcmac, void *data, size_t len)
118*0957b409SSimon J. Gerraty {
119*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_mac(ctx, cbcmac, data, len);
120*0957b409SSimon J. Gerraty br_aes_small_ctrcbc_ctr(ctx, ctr, data, len);
121*0957b409SSimon J. Gerraty }
122*0957b409SSimon J. Gerraty
123*0957b409SSimon J. Gerraty /* see bearssl_block.h */
124*0957b409SSimon J. Gerraty const br_block_ctrcbc_class br_aes_small_ctrcbc_vtable = {
125*0957b409SSimon J. Gerraty sizeof(br_aes_small_ctrcbc_keys),
126*0957b409SSimon J. Gerraty 16,
127*0957b409SSimon J. Gerraty 4,
128*0957b409SSimon J. Gerraty (void (*)(const br_block_ctrcbc_class **, const void *, size_t))
129*0957b409SSimon J. Gerraty &br_aes_small_ctrcbc_init,
130*0957b409SSimon J. Gerraty (void (*)(const br_block_ctrcbc_class *const *,
131*0957b409SSimon J. Gerraty void *, void *, void *, size_t))
132*0957b409SSimon J. Gerraty &br_aes_small_ctrcbc_encrypt,
133*0957b409SSimon J. Gerraty (void (*)(const br_block_ctrcbc_class *const *,
134*0957b409SSimon J. Gerraty void *, void *, void *, size_t))
135*0957b409SSimon J. Gerraty &br_aes_small_ctrcbc_decrypt,
136*0957b409SSimon J. Gerraty (void (*)(const br_block_ctrcbc_class *const *,
137*0957b409SSimon J. Gerraty void *, void *, size_t))
138*0957b409SSimon J. Gerraty &br_aes_small_ctrcbc_ctr,
139*0957b409SSimon J. Gerraty (void (*)(const br_block_ctrcbc_class *const *,
140*0957b409SSimon J. Gerraty void *, const void *, size_t))
141*0957b409SSimon J. Gerraty &br_aes_small_ctrcbc_mac
142*0957b409SSimon J. Gerraty };
143