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
27static int
28sr_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_rsa_context *pc;
33	const br_suite_translated *st;
34	size_t u, st_num;
35	unsigned hash_id;
36	int fh;
37
38	pc = (br_ssl_server_policy_rsa_context *)pctx;
39	st = br_ssl_server_get_client_suites(cc, &st_num);
40	if (cc->eng.session.version < BR_TLS12) {
41		hash_id = 0;
42		fh = 1;
43	} else {
44		hash_id = br_ssl_choose_hash(
45			br_ssl_server_get_client_hashes(cc));
46		fh = (hash_id != 0);
47	}
48	choices->chain = pc->chain;
49	choices->chain_len = pc->chain_len;
50	for (u = 0; u < st_num; u ++) {
51		unsigned tt;
52
53		tt = st[u][1];
54		switch (tt >> 12) {
55		case BR_SSLKEYX_RSA:
56			if ((pc->allowed_usages & BR_KEYTYPE_KEYX) != 0) {
57				choices->cipher_suite = st[u][0];
58				return 1;
59			}
60			break;
61		case BR_SSLKEYX_ECDHE_RSA:
62			if ((pc->allowed_usages & BR_KEYTYPE_SIGN) != 0 && fh) {
63				choices->cipher_suite = st[u][0];
64				choices->algo_id = hash_id + 0xFF00;
65				return 1;
66			}
67			break;
68		}
69	}
70	return 0;
71}
72
73static uint32_t
74sr_do_keyx(const br_ssl_server_policy_class **pctx,
75	unsigned char *data, size_t *len)
76{
77	br_ssl_server_policy_rsa_context *pc;
78
79	pc = (br_ssl_server_policy_rsa_context *)pctx;
80	return br_rsa_ssl_decrypt(pc->irsacore, pc->sk, data, *len);
81}
82
83/*
84 * OID for hash functions in RSA signatures.
85 */
86static const unsigned char HASH_OID_SHA1[] = {
87	0x05, 0x2B, 0x0E, 0x03, 0x02, 0x1A
88};
89
90static const unsigned char HASH_OID_SHA224[] = {
91	0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04
92};
93
94static const unsigned char HASH_OID_SHA256[] = {
95	0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01
96};
97
98static const unsigned char HASH_OID_SHA384[] = {
99	0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02
100};
101
102static const unsigned char HASH_OID_SHA512[] = {
103	0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03
104};
105
106static const unsigned char *HASH_OID[] = {
107	HASH_OID_SHA1,
108	HASH_OID_SHA224,
109	HASH_OID_SHA256,
110	HASH_OID_SHA384,
111	HASH_OID_SHA512
112};
113
114static size_t
115sr_do_sign(const br_ssl_server_policy_class **pctx,
116	unsigned algo_id, unsigned char *data, size_t hv_len, size_t len)
117{
118	br_ssl_server_policy_rsa_context *pc;
119	unsigned char hv[64];
120	size_t sig_len;
121	const unsigned char *hash_oid;
122
123	pc = (br_ssl_server_policy_rsa_context *)pctx;
124	memcpy(hv, data, hv_len);
125	algo_id &= 0xFF;
126	if (algo_id == 0) {
127		hash_oid = NULL;
128	} else if (algo_id >= 2 && algo_id <= 6) {
129		hash_oid = HASH_OID[algo_id - 2];
130	} else {
131		return 0;
132	}
133	sig_len = (pc->sk->n_bitlen + 7) >> 3;
134	if (len < sig_len) {
135		return 0;
136	}
137	return pc->irsasign(hash_oid, hv, hv_len, pc->sk, data) ? sig_len : 0;
138}
139
140static const br_ssl_server_policy_class sr_policy_vtable = {
141	sizeof(br_ssl_server_policy_rsa_context),
142	sr_choose,
143	sr_do_keyx,
144	sr_do_sign
145};
146
147/* see bearssl_ssl.h */
148void
149br_ssl_server_set_single_rsa(br_ssl_server_context *cc,
150	const br_x509_certificate *chain, size_t chain_len,
151	const br_rsa_private_key *sk, unsigned allowed_usages,
152	br_rsa_private irsacore, br_rsa_pkcs1_sign irsasign)
153{
154	cc->chain_handler.single_rsa.vtable = &sr_policy_vtable;
155	cc->chain_handler.single_rsa.chain = chain;
156	cc->chain_handler.single_rsa.chain_len = chain_len;
157	cc->chain_handler.single_rsa.sk = sk;
158	cc->chain_handler.single_rsa.allowed_usages = allowed_usages;
159	cc->chain_handler.single_rsa.irsacore = irsacore;
160	cc->chain_handler.single_rsa.irsasign = irsasign;
161	cc->policy_vtable = &cc->chain_handler.single_rsa.vtable;
162}
163