lib/libtls/tls_conninfo.c

   1 /* $OpenBSD: tls_conninfo.c,v 1.16 2017/08/27 01:39:26 beck Exp $ */
   2 /*
   3  * Copyright (c) 2015 Joel Sing <jsing@openbsd.org>
   4  * Copyright (c) 2015 Bob Beck <beck@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <stdio.h>
  20
  21 #include <openssl/x509.h>
  22
  23 #include <tls.h>
  24 #include "tls_internal.h"
  25
  26 int ASN1_time_tm_clamp_notafter(struct tm *tm);
  27
  28 int
  29 tls_hex_string(const unsigned char *in, size_t inlen, char **out,
  30     size_t *outlen)
  31 {
  32         static const char hex[] = "0123456789abcdef";
  33         size_t i, len;
  34         char *p;
  35
  36         if (outlen != NULL)
  37                 *outlen = 0;
  38
  39         if (inlen >= SIZE_MAX)
  40                 return (-1);
  41         if ((*out = reallocarray(NULL, inlen + 1, 2)) == NULL)
  42                 return (-1);
  43
  44         p = *out;
  45         len = 0;
  46         for (i = 0; i < inlen; i++) {
  47                 p[len++] = hex[(in[i] >> 4) & 0x0f];
  48                 p[len++] = hex[in[i] & 0x0f];
  49         }
  50         p[len++] = 0;
  51
  52         if (outlen != NULL)
  53                 *outlen = len;
  54
  55         return (0);
  56 }
  57
  58 static int
  59 tls_get_peer_cert_hash(struct tls *ctx, char **hash)
  60 {
  61         *hash = NULL;
  62         if (ctx->ssl_peer_cert == NULL)
  63                 return (0);
  64
  65         if (tls_cert_hash(ctx->ssl_peer_cert, hash) == -1) {
  66                 tls_set_errorx(ctx, "unable to compute peer certificate hash - out of memory");
  67                 *hash = NULL;
  68                 return -1;
  69         }
  70         return 0;
  71 }
  72
  73 static int
  74 tls_get_peer_cert_issuer(struct tls *ctx,  char **issuer)
  75 {
  76         X509_NAME *name = NULL;
  77
  78         *issuer = NULL;
  79         if (ctx->ssl_peer_cert == NULL)
  80                 return (-1);
  81         if ((name = X509_get_issuer_name(ctx->ssl_peer_cert)) == NULL)
  82                 return (-1);
  83         *issuer = X509_NAME_oneline(name, 0, 0);
  84         if (*issuer == NULL)
  85                 return (-1);
  86         return (0);
  87 }
  88
  89 static int
  90 tls_get_peer_cert_subject(struct tls *ctx, char **subject)
  91 {
  92         X509_NAME *name = NULL;
  93
  94         *subject = NULL;
  95         if (ctx->ssl_peer_cert == NULL)
  96                 return (-1);
  97         if ((name = X509_get_subject_name(ctx->ssl_peer_cert)) == NULL)
  98                 return (-1);
  99         *subject = X509_NAME_oneline(name, 0, 0);
 100         if (*subject == NULL)
 101                 return (-1);
 102         return (0);
 103 }
 104
 105 static int
 106 tls_get_peer_cert_times(struct tls *ctx, time_t *notbefore,
 107     time_t *notafter)
 108 {
 109         struct tm before_tm, after_tm;
 110         ASN1_TIME *before, *after;
 111
 112         if (ctx->ssl_peer_cert == NULL)
 113                 return (-1);
 114
 115         memset(&before_tm, 0, sizeof(before_tm));
 116         memset(&after_tm, 0, sizeof(after_tm));
 117
 118         if ((before = X509_get_notBefore(ctx->ssl_peer_cert)) == NULL)
 119                 goto err;
 120         if ((after = X509_get_notAfter(ctx->ssl_peer_cert)) == NULL)
 121                 goto err;
 122         if (ASN1_time_parse(before->data, before->length, &before_tm, 0) == -1)
 123                 goto err;
 124         if (ASN1_time_parse(after->data, after->length, &after_tm, 0) == -1)
 125                 goto err;
 126         if (!ASN1_time_tm_clamp_notafter(&after_tm))
 127                 goto err;
 128         if ((*notbefore = timegm(&before_tm)) == -1)
 129                 goto err;
 130         if ((*notafter = timegm(&after_tm)) == -1)
 131                 goto err;
 132
 133         return (0);
 134
 135  err:
 136         return (-1);
 137 }
 138
 139 static int
 140 tls_get_peer_cert_info(struct tls *ctx)
 141 {
 142         if (ctx->ssl_peer_cert == NULL)
 143                 return (0);
 144
 145         if (tls_get_peer_cert_hash(ctx, &ctx->conninfo->hash) == -1)
 146                 goto err;
 147         if (tls_get_peer_cert_subject(ctx, &ctx->conninfo->subject) == -1)
 148                 goto err;
 149         if (tls_get_peer_cert_issuer(ctx, &ctx->conninfo->issuer) == -1)
 150                 goto err;
 151         if (tls_get_peer_cert_times(ctx, &ctx->conninfo->notbefore,
 152             &ctx->conninfo->notafter) == -1)
 153                 goto err;
 154
 155         return (0);
 156
 157  err:
 158         return (-1);
 159 }
 160
 161 static int
 162 tls_conninfo_alpn_proto(struct tls *ctx)
 163 {
 164         const unsigned char *p;
 165         unsigned int len;
 166
 167         free(ctx->conninfo->alpn);
 168         ctx->conninfo->alpn = NULL;
 169
 170         SSL_get0_alpn_selected(ctx->ssl_conn, &p, &len);
 171         if (len > 0) {
 172                 if ((ctx->conninfo->alpn = malloc(len + 1)) == NULL)
 173                         return (-1);
 174                 memcpy(ctx->conninfo->alpn, p, len);
 175                 ctx->conninfo->alpn[len] = '\0';
 176         }
 177
 178         return (0);
 179 }
 180
 181 static int
 182 tls_conninfo_cert_pem(struct tls *ctx)
 183 {
 184         int i, rv = -1;
 185         BIO *membio = NULL;
 186         BUF_MEM *bptr = NULL;
 187
 188         if (ctx->conninfo == NULL)
 189                 goto err;
 190         if (ctx->ssl_peer_cert == NULL)
 191                 return 0;
 192         if ((membio = BIO_new(BIO_s_mem()))== NULL)
 193                 goto err;
 194
 195         /*
 196          * We have to write the peer cert out separately, because
 197          * the certificate chain may or may not contain it.
 198          */
 199         if (!PEM_write_bio_X509(membio, ctx->ssl_peer_cert))
 200                 goto err;
 201         for (i = 0; i < sk_X509_num(ctx->ssl_peer_chain); i++) {
 202                 X509 *chaincert = sk_X509_value(ctx->ssl_peer_chain, i);
 203                 if (chaincert != ctx->ssl_peer_cert &&
 204                     !PEM_write_bio_X509(membio, chaincert))
 205                         goto err;
 206         }
 207
 208         BIO_get_mem_ptr(membio, &bptr);
 209         free(ctx->conninfo->peer_cert);
 210         ctx->conninfo->peer_cert_len = 0;
 211         if ((ctx->conninfo->peer_cert = malloc(bptr->length)) == NULL)
 212                 goto err;
 213         ctx->conninfo->peer_cert_len = bptr->length;
 214         memcpy(ctx->conninfo->peer_cert, bptr->data,
 215             ctx->conninfo->peer_cert_len);
 216
 217         /* BIO_free() will kill BUF_MEM - because we have not set BIO_NOCLOSE */
 218         rv = 0;
 219  err:
 220         BIO_free(membio);
 221         return rv;
 222 }
 223
 224 int
 225 tls_conninfo_populate(struct tls *ctx)
 226 {
 227         const char *tmp;
 228
 229         tls_conninfo_free(ctx->conninfo);
 230
 231         if ((ctx->conninfo = calloc(1, sizeof(struct tls_conninfo))) == NULL) {
 232                 tls_set_errorx(ctx, "out of memory");
 233                 goto err;
 234         }
 235
 236         if (tls_conninfo_alpn_proto(ctx) == -1)
 237                 goto err;
 238
 239         if ((tmp = SSL_get_cipher(ctx->ssl_conn)) == NULL)
 240                 goto err;
 241         ctx->conninfo->cipher = strdup(tmp);
 242         if (ctx->conninfo->cipher == NULL)
 243                 goto err;
 244
 245         if (ctx->servername != NULL) {
 246                 if ((ctx->conninfo->servername =
 247                     strdup(ctx->servername)) == NULL)
 248                         goto err;
 249         }
 250
 251         if ((tmp = SSL_get_version(ctx->ssl_conn)) == NULL)
 252                 goto err;
 253         ctx->conninfo->version = strdup(tmp);
 254         if (ctx->conninfo->version == NULL)
 255                 goto err;
 256
 257         if (tls_get_peer_cert_info(ctx) == -1)
 258                 goto err;
 259
 260         if (tls_conninfo_cert_pem(ctx) == -1)
 261                 goto err;
 262
 263         return (0);
 264
 265  err:
 266         tls_conninfo_free(ctx->conninfo);
 267         ctx->conninfo = NULL;
 268
 269         return (-1);
 270 }
 271
 272 void
 273 tls_conninfo_free(struct tls_conninfo *conninfo)
 274 {
 275         if (conninfo == NULL)
 276                 return;
 277
 278         free(conninfo->alpn);
 279         conninfo->alpn = NULL;
 280         free(conninfo->cipher);
 281         conninfo->cipher = NULL;
 282         free(conninfo->servername);
 283         conninfo->servername = NULL;
 284         free(conninfo->version);
 285         conninfo->version = NULL;
 286
 287         free(conninfo->hash);
 288         conninfo->hash = NULL;
 289         free(conninfo->issuer);
 290         conninfo->issuer = NULL;
 291         free(conninfo->subject);
 292         conninfo->subject = NULL;
 293
 294         free(conninfo->peer_cert);
 295         conninfo->peer_cert = NULL;
 296         conninfo->peer_cert_len = 0;
 297
 298         free(conninfo);
 299 }
 300
 301 const char *
 302 tls_conn_alpn_selected(struct tls *ctx)
 303 {
 304         if (ctx->conninfo == NULL)
 305                 return (NULL);
 306         return (ctx->conninfo->alpn);
 307 }
 308
 309 const char *
 310 tls_conn_cipher(struct tls *ctx)
 311 {
 312         if (ctx->conninfo == NULL)
 313                 return (NULL);
 314         return (ctx->conninfo->cipher);
 315 }
 316
 317 const char *
 318 tls_conn_servername(struct tls *ctx)
 319 {
 320         if (ctx->conninfo == NULL)
 321                 return (NULL);
 322         return (ctx->conninfo->servername);
 323 }
 324
 325 const char *
 326 tls_conn_version(struct tls *ctx)
 327 {
 328         if (ctx->conninfo == NULL)
 329                 return (NULL);
 330         return (ctx->conninfo->version);
 331 }
 332