xref: /freebsd/contrib/bearssl/src/ssl/ssl_scert_single_ec.c (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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 static int
28 se_choose(const br_ssl_server_policy_class **pctx,
29 	const br_ssl_server_context *cc,
30 	br_ssl_server_choices *choices)
31 {
32 	br_ssl_server_policy_ec_context *pc;
33 	const br_suite_translated *st;
34 	size_t u, st_num;
35 	unsigned hash_id;
36 
37 	pc = (br_ssl_server_policy_ec_context *)pctx;
38 	st = br_ssl_server_get_client_suites(cc, &st_num);
39 	hash_id = br_ssl_choose_hash(br_ssl_server_get_client_hashes(cc) >> 8);
40 	if (cc->eng.session.version < BR_TLS12) {
41 		hash_id = br_sha1_ID;
42 	}
43 	choices->chain = pc->chain;
44 	choices->chain_len = pc->chain_len;
45 	for (u = 0; u < st_num; u ++) {
46 		unsigned tt;
47 
48 		tt = st[u][1];
49 		switch (tt >> 12) {
50 		case BR_SSLKEYX_ECDH_RSA:
51 			if ((pc->allowed_usages & BR_KEYTYPE_KEYX) != 0
52 				&& pc->cert_issuer_key_type == BR_KEYTYPE_RSA)
53 			{
54 				choices->cipher_suite = st[u][0];
55 				return 1;
56 			}
57 			break;
58 		case BR_SSLKEYX_ECDH_ECDSA:
59 			if ((pc->allowed_usages & BR_KEYTYPE_KEYX) != 0
60 				&& pc->cert_issuer_key_type == BR_KEYTYPE_EC)
61 			{
62 				choices->cipher_suite = st[u][0];
63 				return 1;
64 			}
65 			break;
66 		case BR_SSLKEYX_ECDHE_ECDSA:
67 			if ((pc->allowed_usages & BR_KEYTYPE_SIGN) != 0
68 				&& hash_id != 0)
69 			{
70 				choices->cipher_suite = st[u][0];
71 				choices->algo_id = hash_id + 0xFF00;
72 				return 1;
73 			}
74 			break;
75 		}
76 	}
77 	return 0;
78 }
79 
80 static uint32_t
81 se_do_keyx(const br_ssl_server_policy_class **pctx,
82 	unsigned char *data, size_t *len)
83 {
84 	br_ssl_server_policy_ec_context *pc;
85 	uint32_t r;
86 	size_t xoff, xlen;
87 
88 	pc = (br_ssl_server_policy_ec_context *)pctx;
89 	r = pc->iec->mul(data, *len, pc->sk->x, pc->sk->xlen, pc->sk->curve);
90 	xoff = pc->iec->xoff(pc->sk->curve, &xlen);
91 	memmove(data, data + xoff, xlen);
92 	*len = xlen;
93 	return r;
94 }
95 
96 static size_t
97 se_do_sign(const br_ssl_server_policy_class **pctx,
98 	unsigned algo_id, unsigned char *data, size_t hv_len, size_t len)
99 {
100 	br_ssl_server_policy_ec_context *pc;
101 	unsigned char hv[64];
102 	const br_hash_class *hc;
103 
104 	algo_id &= 0xFF;
105 	pc = (br_ssl_server_policy_ec_context *)pctx;
106 	hc = br_multihash_getimpl(pc->mhash, algo_id);
107 	if (hc == NULL) {
108 		return 0;
109 	}
110 	memcpy(hv, data, hv_len);
111 	if (len < 139) {
112 		return 0;
113 	}
114 	return pc->iecdsa(pc->iec, hc, hv, pc->sk, data);
115 }
116 
117 static const br_ssl_server_policy_class se_policy_vtable = {
118 	sizeof(br_ssl_server_policy_ec_context),
119 	se_choose,
120 	se_do_keyx,
121 	se_do_sign
122 };
123 
124 /* see bearssl_ssl.h */
125 void
126 br_ssl_server_set_single_ec(br_ssl_server_context *cc,
127 	const br_x509_certificate *chain, size_t chain_len,
128 	const br_ec_private_key *sk, unsigned allowed_usages,
129 	unsigned cert_issuer_key_type,
130 	const br_ec_impl *iec, br_ecdsa_sign iecdsa)
131 {
132 	cc->chain_handler.single_ec.vtable = &se_policy_vtable;
133 	cc->chain_handler.single_ec.chain = chain;
134 	cc->chain_handler.single_ec.chain_len = chain_len;
135 	cc->chain_handler.single_ec.sk = sk;
136 	cc->chain_handler.single_ec.allowed_usages = allowed_usages;
137 	cc->chain_handler.single_ec.cert_issuer_key_type = cert_issuer_key_type;
138 	cc->chain_handler.single_ec.mhash = &cc->eng.mhash;
139 	cc->chain_handler.single_ec.iec = iec;
140 	cc->chain_handler.single_ec.iecdsa = iecdsa;
141 	cc->policy_vtable = &cc->chain_handler.single_ec.vtable;
142 }
143