_ Git - BearSSL/blob - src/ssl/ssl_client_full.c

   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 */
  28 void
  29 br_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 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          * -- GCM is better than CBC.
  46          * -- AES-128 is preferred over AES-256 (AES-128 is already
  47          *    strong enough, and AES-256 is 40% more expensive).
  48          */
  49         static const uint16_t suites[] = {
  50                 BR_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
  51                 BR_TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
  52                 BR_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
  53                 BR_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
  54                 BR_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
  55                 BR_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
  56                 BR_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
  57                 BR_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
  58                 BR_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
  59                 BR_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
  60                 BR_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
  61                 BR_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
  62                 BR_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
  63                 BR_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
  64                 BR_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
  65                 BR_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
  66                 BR_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
  67                 BR_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
  68                 BR_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
  69                 BR_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
  70                 BR_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
  71                 BR_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
  72                 BR_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
  73                 BR_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
  74                 BR_TLS_RSA_WITH_AES_128_GCM_SHA256,
  75                 BR_TLS_RSA_WITH_AES_256_GCM_SHA384,
  76                 BR_TLS_RSA_WITH_AES_128_CBC_SHA256,
  77                 BR_TLS_RSA_WITH_AES_256_CBC_SHA256,
  78                 BR_TLS_RSA_WITH_AES_128_CBC_SHA,
  79                 BR_TLS_RSA_WITH_AES_256_CBC_SHA,
  80                 BR_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
  81                 BR_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
  82                 BR_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
  83                 BR_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
  84                 BR_TLS_RSA_WITH_3DES_EDE_CBC_SHA
  85         };
  86
  87         /*
  88          * All hash functions are activated.
  89          * Note: the X.509 validation engine will nonetheless refuse to
  90          * validate signatures that use MD5 as hash function.
  91          */
  92         static const br_hash_class *hashes[] = {
  93                 &br_md5_vtable,
  94                 &br_sha1_vtable,
  95                 &br_sha224_vtable,
  96                 &br_sha256_vtable,
  97                 &br_sha384_vtable,
  98                 &br_sha512_vtable
  99         };
 100
 101         int id;
 102
 103         /*
 104          * Reset client context and set supported versions from TLS-1.0
 105          * to TLS-1.2 (inclusive).
 106          */
 107         br_ssl_client_zero(cc);
 108         br_ssl_engine_set_versions(&cc->eng, BR_TLS10, BR_TLS12);
 109
 110         /*
 111          * X.509 engine uses SHA-256 to hash certificate DN (for
 112          * comparisons).
 113          */
 114         br_x509_minimal_init(xc, &br_sha256_vtable,
 115                 trust_anchors, trust_anchors_num);
 116
 117         /*
 118          * Set suites and asymmetric crypto implementations. We use the
 119          * "i31" code for RSA (it is somewhat faster than the "i32"
 120          * implementation).
 121          * TODO: change that when better implementations are made available.
 122          */
 123         br_ssl_engine_set_suites(&cc->eng, suites,
 124                 (sizeof suites) / (sizeof suites[0]));
 125         br_ssl_client_set_rsapub(cc, &br_rsa_i31_public);
 126         br_ssl_engine_set_rsavrfy(&cc->eng, &br_rsa_i31_pkcs1_vrfy);
 127         br_ssl_engine_set_ec(&cc->eng, &br_ec_prime_i31);
 128         br_ssl_engine_set_ecdsa(&cc->eng, &br_ecdsa_i31_vrfy_asn1);
 129         br_x509_minimal_set_rsa(xc, &br_rsa_i31_pkcs1_vrfy);
 130         br_x509_minimal_set_ecdsa(xc,
 131                 &br_ec_prime_i31, &br_ecdsa_i31_vrfy_asn1);
 132
 133         /*
 134          * Set supported hash functions, for the SSL engine and for the
 135          * X.509 engine.
 136          */
 137         for (id = br_md5_ID; id <= br_sha512_ID; id ++) {
 138                 const br_hash_class *hc;
 139
 140                 hc = hashes[id - 1];
 141                 br_ssl_engine_set_hash(&cc->eng, id, hc);
 142                 br_x509_minimal_set_hash(xc, id, hc);
 143         }
 144
 145         /*
 146          * Link the X.509 engine in the SSL engine.
 147          */
 148         br_ssl_engine_set_x509(&cc->eng, &xc->vtable);
 149
 150         /*
 151          * Set the PRF implementations.
 152          */
 153         br_ssl_engine_set_prf10(&cc->eng, &br_tls10_prf);
 154         br_ssl_engine_set_prf_sha256(&cc->eng, &br_tls12_sha256_prf);
 155         br_ssl_engine_set_prf_sha384(&cc->eng, &br_tls12_sha384_prf);
 156
 157         /*
 158          * Symmetric encryption. We use the "constant-time"
 159          * implementations, which are the safest.
 160          *
 161          * On architectures detected as "64-bit", use the 64-bit
 162          * versions (aes_ct64, ghash_ctmul64).
 163          */
 164 #if BR_64
 165         br_ssl_engine_set_aes_cbc(&cc->eng,
 166                 &br_aes_ct64_cbcenc_vtable,
 167                 &br_aes_ct64_cbcdec_vtable);
 168         br_ssl_engine_set_aes_ctr(&cc->eng,
 169                 &br_aes_ct64_ctr_vtable);
 170         br_ssl_engine_set_ghash(&cc->eng,
 171                 &br_ghash_ctmul64);
 172 #else
 173         br_ssl_engine_set_aes_cbc(&cc->eng,
 174                 &br_aes_ct_cbcenc_vtable,
 175                 &br_aes_ct_cbcdec_vtable);
 176         br_ssl_engine_set_aes_ctr(&cc->eng,
 177                 &br_aes_ct_ctr_vtable);
 178         br_ssl_engine_set_ghash(&cc->eng,
 179                 &br_ghash_ctmul);
 180 #endif
 181         br_ssl_engine_set_des_cbc(&cc->eng,
 182                 &br_des_ct_cbcenc_vtable,
 183                 &br_des_ct_cbcdec_vtable);
 184
 185         /*
 186          * Set the SSL record engines (CBC, GCM).
 187          */
 188         br_ssl_engine_set_cbc(&cc->eng,
 189                 &br_sslrec_in_cbc_vtable,
 190                 &br_sslrec_out_cbc_vtable);
 191         br_ssl_engine_set_gcm(&cc->eng,
 192                 &br_sslrec_in_gcm_vtable,
 193                 &br_sslrec_out_gcm_vtable);
 194 }