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_ssl.h */
28void
29br_ssl_client_init_full(br_ssl_client_context *cc,
30	br_x509_minimal_context *xc,
31	const br_x509_trust_anchor *trust_anchors, size_t trust_anchors_num)
32{
33	/*
34	 * The "full" profile supports all implemented cipher suites.
35	 *
36	 * Rationale for suite order, from most important to least
37	 * important rule:
38	 *
39	 * -- Don't use 3DES if AES or ChaCha20 is available.
40	 * -- Try to have Forward Secrecy (ECDHE suite) if possible.
41	 * -- When not using Forward Secrecy, ECDH key exchange is
42	 *    better than RSA key exchange (slightly more expensive on the
43	 *    client, but much cheaper on the server, and it implies smaller
44	 *    messages).
45	 * -- ChaCha20+Poly1305 is better than AES/GCM (faster, smaller code).
46	 * -- GCM is better than CCM and CBC. CCM is better than CBC.
47	 * -- CCM is preferable over CCM_8 (with CCM_8, forgeries may succeed
48	 *    with probability 2^(-64)).
49	 * -- AES-128 is preferred over AES-256 (AES-128 is already
50	 *    strong enough, and AES-256 is 40% more expensive).
51	 */
52	static const uint16_t suites[] = {
53		BR_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
54		BR_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
55		BR_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
56		BR_TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
57		BR_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
58		BR_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
59		BR_TLS_ECDHE_ECDSA_WITH_AES_128_CCM,
60		BR_TLS_ECDHE_ECDSA_WITH_AES_256_CCM,
61		BR_TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8,
62		BR_TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8,
63		BR_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
64		BR_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
65		BR_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
66		BR_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
67		BR_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
68		BR_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
69		BR_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
70		BR_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
71		BR_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
72		BR_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
73		BR_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
74		BR_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
75		BR_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
76		BR_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
77		BR_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
78		BR_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
79		BR_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
80		BR_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
81		BR_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
82		BR_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
83		BR_TLS_RSA_WITH_AES_128_GCM_SHA256,
84		BR_TLS_RSA_WITH_AES_256_GCM_SHA384,
85		BR_TLS_RSA_WITH_AES_128_CCM,
86		BR_TLS_RSA_WITH_AES_256_CCM,
87		BR_TLS_RSA_WITH_AES_128_CCM_8,
88		BR_TLS_RSA_WITH_AES_256_CCM_8,
89		BR_TLS_RSA_WITH_AES_128_CBC_SHA256,
90		BR_TLS_RSA_WITH_AES_256_CBC_SHA256,
91		BR_TLS_RSA_WITH_AES_128_CBC_SHA,
92		BR_TLS_RSA_WITH_AES_256_CBC_SHA,
93		BR_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
94		BR_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
95		BR_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
96		BR_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
97		BR_TLS_RSA_WITH_3DES_EDE_CBC_SHA
98	};
99
100	/*
101	 * All hash functions are activated.
102	 * Note: the X.509 validation engine will nonetheless refuse to
103	 * validate signatures that use MD5 as hash function.
104	 */
105	static const br_hash_class *hashes[] = {
106		&br_md5_vtable,
107		&br_sha1_vtable,
108		&br_sha224_vtable,
109		&br_sha256_vtable,
110		&br_sha384_vtable,
111		&br_sha512_vtable
112	};
113
114	int id;
115
116	/*
117	 * Reset client context and set supported versions from TLS-1.0
118	 * to TLS-1.2 (inclusive).
119	 */
120	br_ssl_client_zero(cc);
121	br_ssl_engine_set_versions(&cc->eng, BR_TLS10, BR_TLS12);
122
123	/*
124	 * X.509 engine uses SHA-256 to hash certificate DN (for
125	 * comparisons).
126	 */
127	br_x509_minimal_init(xc, &br_sha256_vtable,
128		trust_anchors, trust_anchors_num);
129
130	/*
131	 * Set suites and asymmetric crypto implementations. We use the
132	 * "i31" code for RSA (it is somewhat faster than the "i32"
133	 * implementation).
134	 * TODO: change that when better implementations are made available.
135	 */
136	br_ssl_engine_set_suites(&cc->eng, suites,
137		(sizeof suites) / (sizeof suites[0]));
138	br_ssl_client_set_default_rsapub(cc);
139	br_ssl_engine_set_default_rsavrfy(&cc->eng);
140	br_ssl_engine_set_default_ecdsa(&cc->eng);
141	br_x509_minimal_set_rsa(xc, br_ssl_engine_get_rsavrfy(&cc->eng));
142	br_x509_minimal_set_ecdsa(xc,
143		br_ssl_engine_get_ec(&cc->eng),
144		br_ssl_engine_get_ecdsa(&cc->eng));
145
146	/*
147	 * Set supported hash functions, for the SSL engine and for the
148	 * X.509 engine.
149	 */
150	for (id = br_md5_ID; id <= br_sha512_ID; id ++) {
151		const br_hash_class *hc;
152
153		hc = hashes[id - 1];
154		br_ssl_engine_set_hash(&cc->eng, id, hc);
155		br_x509_minimal_set_hash(xc, id, hc);
156	}
157
158	/*
159	 * Link the X.509 engine in the SSL engine.
160	 */
161	br_ssl_engine_set_x509(&cc->eng, &xc->vtable);
162
163	/*
164	 * Set the PRF implementations.
165	 */
166	br_ssl_engine_set_prf10(&cc->eng, &br_tls10_prf);
167	br_ssl_engine_set_prf_sha256(&cc->eng, &br_tls12_sha256_prf);
168	br_ssl_engine_set_prf_sha384(&cc->eng, &br_tls12_sha384_prf);
169
170	/*
171	 * Symmetric encryption. We use the "default" implementations
172	 * (fastest among constant-time implementations).
173	 */
174	br_ssl_engine_set_default_aes_cbc(&cc->eng);
175	br_ssl_engine_set_default_aes_ccm(&cc->eng);
176	br_ssl_engine_set_default_aes_gcm(&cc->eng);
177	br_ssl_engine_set_default_des_cbc(&cc->eng);
178	br_ssl_engine_set_default_chapol(&cc->eng);
179}
180