1 /* $OpenBSD: tls_conninfo.c,v 1.22 2021/01/05 15:57:38 tb 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 if ((before = X509_get_notBefore(ctx->ssl_peer_cert)) == NULL) 116 goto err; 117 if ((after = X509_get_notAfter(ctx->ssl_peer_cert)) == NULL) 118 goto err; 119 if (ASN1_time_parse(before->data, before->length, &before_tm, 0) == -1) 120 goto err; 121 if (ASN1_time_parse(after->data, after->length, &after_tm, 0) == -1) 122 goto err; 123 if (!ASN1_time_tm_clamp_notafter(&after_tm)) 124 goto err; 125 if ((*notbefore = timegm(&before_tm)) == -1) 126 goto err; 127 if ((*notafter = timegm(&after_tm)) == -1) 128 goto err; 129 130 return (0); 131 132 err: 133 return (-1); 134 } 135 136 static int 137 tls_get_peer_cert_info(struct tls *ctx) 138 { 139 if (ctx->ssl_peer_cert == NULL) 140 return (0); 141 142 if (tls_get_peer_cert_hash(ctx, &ctx->conninfo->hash) == -1) 143 goto err; 144 if (tls_get_peer_cert_subject(ctx, &ctx->conninfo->subject) == -1) 145 goto err; 146 if (tls_get_peer_cert_issuer(ctx, &ctx->conninfo->issuer) == -1) 147 goto err; 148 if (tls_get_peer_cert_times(ctx, &ctx->conninfo->notbefore, 149 &ctx->conninfo->notafter) == -1) 150 goto err; 151 152 return (0); 153 154 err: 155 return (-1); 156 } 157 158 static int 159 tls_conninfo_alpn_proto(struct tls *ctx) 160 { 161 const unsigned char *p; 162 unsigned int len; 163 164 free(ctx->conninfo->alpn); 165 ctx->conninfo->alpn = NULL; 166 167 SSL_get0_alpn_selected(ctx->ssl_conn, &p, &len); 168 if (len > 0) { 169 if ((ctx->conninfo->alpn = malloc(len + 1)) == NULL) 170 return (-1); 171 memcpy(ctx->conninfo->alpn, p, len); 172 ctx->conninfo->alpn[len] = '\0'; 173 } 174 175 return (0); 176 } 177 178 static int 179 tls_conninfo_cert_pem(struct tls *ctx) 180 { 181 int i, rv = -1; 182 BIO *membio = NULL; 183 BUF_MEM *bptr = NULL; 184 185 if (ctx->ssl_peer_cert == NULL) 186 return 0; 187 if ((membio = BIO_new(BIO_s_mem()))== NULL) 188 goto err; 189 190 /* 191 * We have to write the peer cert out separately, because 192 * the certificate chain may or may not contain it. 193 */ 194 if (!PEM_write_bio_X509(membio, ctx->ssl_peer_cert)) 195 goto err; 196 for (i = 0; i < sk_X509_num(ctx->ssl_peer_chain); i++) { 197 X509 *chaincert = sk_X509_value(ctx->ssl_peer_chain, i); 198 if (chaincert != ctx->ssl_peer_cert && 199 !PEM_write_bio_X509(membio, chaincert)) 200 goto err; 201 } 202 203 BIO_get_mem_ptr(membio, &bptr); 204 free(ctx->conninfo->peer_cert); 205 ctx->conninfo->peer_cert_len = 0; 206 if ((ctx->conninfo->peer_cert = malloc(bptr->length)) == NULL) 207 goto err; 208 ctx->conninfo->peer_cert_len = bptr->length; 209 memcpy(ctx->conninfo->peer_cert, bptr->data, 210 ctx->conninfo->peer_cert_len); 211 212 /* BIO_free() will kill BUF_MEM - because we have not set BIO_NOCLOSE */ 213 rv = 0; 214 err: 215 BIO_free(membio); 216 return rv; 217 } 218 219 static int 220 tls_conninfo_session(struct tls *ctx) 221 { 222 ctx->conninfo->session_resumed = SSL_session_reused(ctx->ssl_conn); 223 224 return 0; 225 } 226 227 int 228 tls_conninfo_populate(struct tls *ctx) 229 { 230 const char *tmp; 231 232 tls_conninfo_free(ctx->conninfo); 233 234 if ((ctx->conninfo = calloc(1, sizeof(struct tls_conninfo))) == NULL) { 235 tls_set_errorx(ctx, "out of memory"); 236 goto err; 237 } 238 239 if (tls_conninfo_alpn_proto(ctx) == -1) 240 goto err; 241 242 if ((tmp = SSL_get_cipher(ctx->ssl_conn)) == NULL) 243 goto err; 244 if ((ctx->conninfo->cipher = strdup(tmp)) == NULL) 245 goto err; 246 ctx->conninfo->cipher_strength = SSL_get_cipher_bits(ctx->ssl_conn, NULL); 247 248 if (ctx->servername != NULL) { 249 if ((ctx->conninfo->servername = 250 strdup(ctx->servername)) == NULL) 251 goto err; 252 } 253 254 if ((tmp = SSL_get_version(ctx->ssl_conn)) == NULL) 255 goto err; 256 if ((ctx->conninfo->version = strdup(tmp)) == NULL) 257 goto err; 258 259 if (tls_get_peer_cert_info(ctx) == -1) 260 goto err; 261 262 if (tls_conninfo_cert_pem(ctx) == -1) 263 goto err; 264 265 if (tls_conninfo_session(ctx) == -1) 266 goto err; 267 268 return (0); 269 270 err: 271 tls_conninfo_free(ctx->conninfo); 272 ctx->conninfo = NULL; 273 274 return (-1); 275 } 276 277 void 278 tls_conninfo_free(struct tls_conninfo *conninfo) 279 { 280 if (conninfo == NULL) 281 return; 282 283 free(conninfo->alpn); 284 free(conninfo->cipher); 285 free(conninfo->servername); 286 free(conninfo->version); 287 288 free(conninfo->hash); 289 free(conninfo->issuer); 290 free(conninfo->subject); 291 292 free(conninfo->peer_cert); 293 294 free(conninfo); 295 } 296 297 const char * 298 tls_conn_alpn_selected(struct tls *ctx) 299 { 300 if (ctx->conninfo == NULL) 301 return (NULL); 302 return (ctx->conninfo->alpn); 303 } 304 305 const char * 306 tls_conn_cipher(struct tls *ctx) 307 { 308 if (ctx->conninfo == NULL) 309 return (NULL); 310 return (ctx->conninfo->cipher); 311 } 312 313 int 314 tls_conn_cipher_strength(struct tls *ctx) 315 { 316 if (ctx->conninfo == NULL) 317 return (0); 318 return (ctx->conninfo->cipher_strength); 319 } 320 321 const char * 322 tls_conn_servername(struct tls *ctx) 323 { 324 if (ctx->conninfo == NULL) 325 return (NULL); 326 return (ctx->conninfo->servername); 327 } 328 329 int 330 tls_conn_session_resumed(struct tls *ctx) 331 { 332 if (ctx->conninfo == NULL) 333 return (0); 334 return (ctx->conninfo->session_resumed); 335 } 336 337 const char * 338 tls_conn_version(struct tls *ctx) 339 { 340 if (ctx->conninfo == NULL) 341 return (NULL); 342 return (ctx->conninfo->version); 343 } 344