_ Git - BearSSL/blob - src/ssl/ssl_single_ec.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 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         int 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));
  40         choices->chain = pc->chain;
  41         choices->chain_len = pc->chain_len;
  42         for (u = 0; u < st_num; u ++) {
  43                 unsigned tt;
  44
  45                 tt = st[u][1];
  46                 switch (tt >> 12) {
  47                 case BR_SSLKEYX_ECDH_RSA:
  48                         if ((pc->allowed_usages & BR_KEYTYPE_KEYX) != 0
  49                                 && pc->cert_issuer_key_type == BR_KEYTYPE_RSA)
  50                         {
  51                                 choices->cipher_suite = st[u][0];
  52                                 return 1;
  53                         }
  54                         break;
  55                 case BR_SSLKEYX_ECDH_ECDSA:
  56                         if ((pc->allowed_usages & BR_KEYTYPE_KEYX) != 0
  57                                 && pc->cert_issuer_key_type == BR_KEYTYPE_EC)
  58                         {
  59                                 choices->cipher_suite = st[u][0];
  60                                 return 1;
  61                         }
  62                         break;
  63                 case BR_SSLKEYX_ECDHE_ECDSA:
  64                         if ((pc->allowed_usages & BR_KEYTYPE_SIGN) != 0
  65                                 && hash_id != 0)
  66                         {
  67                                 choices->cipher_suite = st[u][0];
  68                                 choices->hash_id = hash_id;
  69                                 return 1;
  70                         }
  71                         break;
  72                 }
  73         }
  74         return 0;
  75 }
  76
  77 static uint32_t
  78 se_do_keyx(const br_ssl_server_policy_class **pctx,
  79         unsigned char *data, size_t len)
  80 {
  81         br_ssl_server_policy_ec_context *pc;
  82
  83         pc = (br_ssl_server_policy_ec_context *)pctx;
  84         return pc->iec->mul(data, len, pc->sk->x, pc->sk->xlen, pc->sk->curve);
  85 }
  86
  87 static size_t
  88 se_do_sign(const br_ssl_server_policy_class **pctx,
  89         int hash_id, size_t hv_len, unsigned char *data, size_t len)
  90 {
  91         br_ssl_server_policy_ec_context *pc;
  92         unsigned char hv[64];
  93         const br_hash_class *hc;
  94
  95         pc = (br_ssl_server_policy_ec_context *)pctx;
  96         hc = br_multihash_getimpl(pc->mhash, hash_id);
  97         if (hc == NULL) {
  98                 return 0;
  99         }
 100         memcpy(hv, data, hv_len);
 101         if (len < 139) {
 102                 return 0;
 103         }
 104         return pc->iecdsa(pc->iec, hc, hv, pc->sk, data);
 105 }
 106
 107 static const br_ssl_server_policy_class se_policy_vtable = {
 108         sizeof(br_ssl_server_policy_ec_context),
 109         se_choose,
 110         se_do_keyx,
 111         se_do_sign
 112 };
 113
 114 /* see bearssl_ssl.h */
 115 void
 116 br_ssl_server_set_single_ec(br_ssl_server_context *cc,
 117         const br_x509_certificate *chain, size_t chain_len,
 118         const br_ec_private_key *sk, unsigned allowed_usages,
 119         unsigned cert_issuer_key_type,
 120         const br_ec_impl *iec, br_ecdsa_sign iecdsa)
 121 {
 122         cc->chain_handler.single_ec.vtable = &se_policy_vtable;
 123         cc->chain_handler.single_ec.chain = chain;
 124         cc->chain_handler.single_ec.chain_len = chain_len;
 125         cc->chain_handler.single_ec.sk = sk;
 126         cc->chain_handler.single_ec.allowed_usages = allowed_usages;
 127         cc->chain_handler.single_ec.cert_issuer_key_type = cert_issuer_key_type;
 128         cc->chain_handler.single_ec.mhash = &cc->eng.mhash;
 129         cc->chain_handler.single_ec.iec = iec;
 130         cc->chain_handler.single_ec.iecdsa = iecdsa;
 131         cc->policy_vtable = &cc->chain_handler.single_ec.vtable;
 132 }