1 /* $OpenBSD: ssl_asn1.c,v 1.69 2024/07/22 14:47:15 jsing Exp $ */ 2 /* 3 * Copyright (c) 2016 Joel Sing <jsing@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <limits.h> 19 20 #include <openssl/ssl.h> 21 #include <openssl/x509.h> 22 23 #include "bytestring.h" 24 #include "ssl_local.h" 25 26 #define SSLASN1_TAG (CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC) 27 #define SSLASN1_TIME_TAG (SSLASN1_TAG | 1) 28 #define SSLASN1_TIMEOUT_TAG (SSLASN1_TAG | 2) 29 #define SSLASN1_PEER_CERT_TAG (SSLASN1_TAG | 3) 30 #define SSLASN1_SESSION_ID_CTX_TAG (SSLASN1_TAG | 4) 31 #define SSLASN1_VERIFY_RESULT_TAG (SSLASN1_TAG | 5) 32 #define SSLASN1_HOSTNAME_TAG (SSLASN1_TAG | 6) 33 #define SSLASN1_LIFETIME_TAG (SSLASN1_TAG | 9) 34 #define SSLASN1_TICKET_TAG (SSLASN1_TAG | 10) 35 36 static uint64_t 37 time_max(void) 38 { 39 if (sizeof(time_t) == sizeof(int32_t)) 40 return INT32_MAX; 41 if (sizeof(time_t) == sizeof(int64_t)) 42 return INT64_MAX; 43 return 0; 44 } 45 46 static int 47 SSL_SESSION_encode(SSL_SESSION *s, unsigned char **out, size_t *out_len, 48 int ticket_encoding) 49 { 50 CBB cbb, session, cipher_suite, session_id, master_key, time, timeout; 51 CBB peer_cert, sidctx, verify_result, hostname, lifetime, ticket, value; 52 unsigned char *peer_cert_bytes = NULL; 53 int len, rv = 0; 54 55 if (!CBB_init(&cbb, 0)) 56 goto err; 57 58 if (!CBB_add_asn1(&cbb, &session, CBS_ASN1_SEQUENCE)) 59 goto err; 60 61 /* Session ASN1 version. */ 62 if (!CBB_add_asn1_uint64(&session, SSL_SESSION_ASN1_VERSION)) 63 goto err; 64 65 /* TLS/SSL protocol version. */ 66 if (s->ssl_version < 0) 67 goto err; 68 if (!CBB_add_asn1_uint64(&session, s->ssl_version)) 69 goto err; 70 71 /* Cipher suite value. */ 72 if (!CBB_add_asn1(&session, &cipher_suite, CBS_ASN1_OCTETSTRING)) 73 goto err; 74 if (!CBB_add_u16(&cipher_suite, s->cipher_value)) 75 goto err; 76 77 /* Session ID - zero length for a ticket. */ 78 if (!CBB_add_asn1(&session, &session_id, CBS_ASN1_OCTETSTRING)) 79 goto err; 80 if (!CBB_add_bytes(&session_id, s->session_id, 81 ticket_encoding ? 0 : s->session_id_length)) 82 goto err; 83 84 /* Master key. */ 85 if (!CBB_add_asn1(&session, &master_key, CBS_ASN1_OCTETSTRING)) 86 goto err; 87 if (!CBB_add_bytes(&master_key, s->master_key, s->master_key_length)) 88 goto err; 89 90 /* Time [1]. */ 91 if (s->time != 0) { 92 if (s->time < 0) 93 goto err; 94 if (!CBB_add_asn1(&session, &time, SSLASN1_TIME_TAG)) 95 goto err; 96 if (!CBB_add_asn1_uint64(&time, s->time)) 97 goto err; 98 } 99 100 /* Timeout [2]. */ 101 if (s->timeout != 0) { 102 if (s->timeout < 0) 103 goto err; 104 if (!CBB_add_asn1(&session, &timeout, SSLASN1_TIMEOUT_TAG)) 105 goto err; 106 if (!CBB_add_asn1_uint64(&timeout, s->timeout)) 107 goto err; 108 } 109 110 /* Peer certificate [3]. */ 111 if (s->peer_cert != NULL) { 112 if ((len = i2d_X509(s->peer_cert, &peer_cert_bytes)) <= 0) 113 goto err; 114 if (!CBB_add_asn1(&session, &peer_cert, SSLASN1_PEER_CERT_TAG)) 115 goto err; 116 if (!CBB_add_bytes(&peer_cert, peer_cert_bytes, len)) 117 goto err; 118 } 119 120 /* Session ID context [4]. */ 121 /* XXX - Actually handle this as optional? */ 122 if (!CBB_add_asn1(&session, &sidctx, SSLASN1_SESSION_ID_CTX_TAG)) 123 goto err; 124 if (!CBB_add_asn1(&sidctx, &value, CBS_ASN1_OCTETSTRING)) 125 goto err; 126 if (!CBB_add_bytes(&value, s->sid_ctx, s->sid_ctx_length)) 127 goto err; 128 129 /* Verify result [5]. */ 130 if (s->verify_result != X509_V_OK) { 131 if (s->verify_result < 0) 132 goto err; 133 if (!CBB_add_asn1(&session, &verify_result, 134 SSLASN1_VERIFY_RESULT_TAG)) 135 goto err; 136 if (!CBB_add_asn1_uint64(&verify_result, s->verify_result)) 137 goto err; 138 } 139 140 /* Hostname [6]. */ 141 if (s->tlsext_hostname != NULL) { 142 if (!CBB_add_asn1(&session, &hostname, SSLASN1_HOSTNAME_TAG)) 143 goto err; 144 if (!CBB_add_asn1(&hostname, &value, CBS_ASN1_OCTETSTRING)) 145 goto err; 146 if (!CBB_add_bytes(&value, (const uint8_t *)s->tlsext_hostname, 147 strlen(s->tlsext_hostname))) 148 goto err; 149 } 150 151 /* PSK identity hint [7]. */ 152 /* PSK identity [8]. */ 153 154 /* Ticket lifetime hint [9]. */ 155 if (s->tlsext_tick_lifetime_hint > 0) { 156 if (!CBB_add_asn1(&session, &lifetime, SSLASN1_LIFETIME_TAG)) 157 goto err; 158 if (!CBB_add_asn1_uint64(&lifetime, 159 s->tlsext_tick_lifetime_hint)) 160 goto err; 161 } 162 163 /* Ticket [10]. */ 164 if (s->tlsext_tick != NULL) { 165 if (!CBB_add_asn1(&session, &ticket, SSLASN1_TICKET_TAG)) 166 goto err; 167 if (!CBB_add_asn1(&ticket, &value, CBS_ASN1_OCTETSTRING)) 168 goto err; 169 if (!CBB_add_bytes(&value, s->tlsext_tick, s->tlsext_ticklen)) 170 goto err; 171 } 172 173 /* Compression method [11]. */ 174 /* SRP username [12]. */ 175 176 if (!CBB_finish(&cbb, out, out_len)) 177 goto err; 178 179 rv = 1; 180 181 err: 182 CBB_cleanup(&cbb); 183 free(peer_cert_bytes); 184 185 return rv; 186 } 187 188 int 189 SSL_SESSION_ticket(SSL_SESSION *ss, unsigned char **out, size_t *out_len) 190 { 191 if (ss == NULL) 192 return 0; 193 194 if (ss->cipher_value == 0) 195 return 0; 196 197 return SSL_SESSION_encode(ss, out, out_len, 1); 198 } 199 200 int 201 i2d_SSL_SESSION(SSL_SESSION *ss, unsigned char **pp) 202 { 203 unsigned char *data = NULL; 204 size_t data_len = 0; 205 int rv = -1; 206 207 if (ss == NULL) 208 return 0; 209 210 if (ss->cipher_value == 0) 211 return 0; 212 213 if (!SSL_SESSION_encode(ss, &data, &data_len, 0)) 214 goto err; 215 216 if (data_len > INT_MAX) 217 goto err; 218 219 if (pp != NULL) { 220 if (*pp == NULL) { 221 *pp = data; 222 data = NULL; 223 } else { 224 memcpy(*pp, data, data_len); 225 *pp += data_len; 226 } 227 } 228 229 rv = (int)data_len; 230 231 err: 232 freezero(data, data_len); 233 234 return rv; 235 } 236 LSSL_ALIAS(i2d_SSL_SESSION); 237 238 SSL_SESSION * 239 d2i_SSL_SESSION(SSL_SESSION **a, const unsigned char **pp, long length) 240 { 241 CBS cbs, session, cipher_suite, session_id, master_key, peer_cert; 242 CBS hostname, ticket; 243 uint64_t version, tls_version, stime, timeout, verify_result, lifetime; 244 const unsigned char *peer_cert_bytes; 245 SSL_SESSION *s = NULL; 246 size_t data_len; 247 int present; 248 249 if (a != NULL) 250 s = *a; 251 252 if (s == NULL) { 253 if ((s = SSL_SESSION_new()) == NULL) { 254 SSLerrorx(ERR_R_MALLOC_FAILURE); 255 return (NULL); 256 } 257 } 258 259 CBS_init(&cbs, *pp, length); 260 261 if (!CBS_get_asn1(&cbs, &session, CBS_ASN1_SEQUENCE)) 262 goto err; 263 264 /* Session ASN1 version. */ 265 if (!CBS_get_asn1_uint64(&session, &version)) 266 goto err; 267 if (version != SSL_SESSION_ASN1_VERSION) 268 goto err; 269 270 /* TLS/SSL Protocol Version. */ 271 if (!CBS_get_asn1_uint64(&session, &tls_version)) 272 goto err; 273 if (tls_version > INT_MAX) 274 goto err; 275 s->ssl_version = (int)tls_version; 276 277 /* Cipher suite value. */ 278 if (!CBS_get_asn1(&session, &cipher_suite, CBS_ASN1_OCTETSTRING)) 279 goto err; 280 if (!CBS_get_u16(&cipher_suite, &s->cipher_value)) 281 goto err; 282 if (CBS_len(&cipher_suite) != 0) 283 goto err; 284 285 /* Session ID. */ 286 if (!CBS_get_asn1(&session, &session_id, CBS_ASN1_OCTETSTRING)) 287 goto err; 288 if (!CBS_write_bytes(&session_id, s->session_id, sizeof(s->session_id), 289 &s->session_id_length)) 290 goto err; 291 292 /* Master key. */ 293 if (!CBS_get_asn1(&session, &master_key, CBS_ASN1_OCTETSTRING)) 294 goto err; 295 if (!CBS_write_bytes(&master_key, s->master_key, sizeof(s->master_key), 296 &s->master_key_length)) 297 goto err; 298 299 /* Time [1]. */ 300 s->time = time(NULL); 301 if (!CBS_get_optional_asn1_uint64(&session, &stime, SSLASN1_TIME_TAG, 302 0)) 303 goto err; 304 if (stime > time_max()) 305 goto err; 306 if (stime != 0) 307 s->time = (time_t)stime; 308 309 /* Timeout [2]. */ 310 s->timeout = 3; 311 if (!CBS_get_optional_asn1_uint64(&session, &timeout, 312 SSLASN1_TIMEOUT_TAG, 0)) 313 goto err; 314 if (timeout > LONG_MAX) 315 goto err; 316 if (timeout != 0) 317 s->timeout = (long)timeout; 318 319 /* Peer certificate [3]. */ 320 X509_free(s->peer_cert); 321 s->peer_cert = NULL; 322 if (!CBS_get_optional_asn1(&session, &peer_cert, &present, 323 SSLASN1_PEER_CERT_TAG)) 324 goto err; 325 if (present) { 326 data_len = CBS_len(&peer_cert); 327 if (data_len > LONG_MAX) 328 goto err; 329 peer_cert_bytes = CBS_data(&peer_cert); 330 if (d2i_X509(&s->peer_cert, &peer_cert_bytes, 331 (long)data_len) == NULL) 332 goto err; 333 } 334 335 /* Session ID context [4]. */ 336 s->sid_ctx_length = 0; 337 if (!CBS_get_optional_asn1_octet_string(&session, &session_id, &present, 338 SSLASN1_SESSION_ID_CTX_TAG)) 339 goto err; 340 if (present) { 341 if (!CBS_write_bytes(&session_id, (uint8_t *)&s->sid_ctx, 342 sizeof(s->sid_ctx), &s->sid_ctx_length)) 343 goto err; 344 } 345 346 /* Verify result [5]. */ 347 s->verify_result = X509_V_OK; 348 if (!CBS_get_optional_asn1_uint64(&session, &verify_result, 349 SSLASN1_VERIFY_RESULT_TAG, X509_V_OK)) 350 goto err; 351 if (verify_result > LONG_MAX) 352 goto err; 353 s->verify_result = (long)verify_result; 354 355 /* Hostname [6]. */ 356 free(s->tlsext_hostname); 357 s->tlsext_hostname = NULL; 358 if (!CBS_get_optional_asn1_octet_string(&session, &hostname, &present, 359 SSLASN1_HOSTNAME_TAG)) 360 goto err; 361 if (present) { 362 if (CBS_contains_zero_byte(&hostname)) 363 goto err; 364 if (!CBS_strdup(&hostname, &s->tlsext_hostname)) 365 goto err; 366 } 367 368 /* PSK identity hint [7]. */ 369 /* PSK identity [8]. */ 370 371 /* Ticket lifetime [9]. */ 372 s->tlsext_tick_lifetime_hint = 0; 373 if (!CBS_get_optional_asn1_uint64(&session, &lifetime, 374 SSLASN1_LIFETIME_TAG, 0)) 375 goto err; 376 if (lifetime > UINT32_MAX) 377 goto err; 378 if (lifetime > 0) 379 s->tlsext_tick_lifetime_hint = (uint32_t)lifetime; 380 381 /* Ticket [10]. */ 382 free(s->tlsext_tick); 383 s->tlsext_tick = NULL; 384 if (!CBS_get_optional_asn1_octet_string(&session, &ticket, &present, 385 SSLASN1_TICKET_TAG)) 386 goto err; 387 if (present) { 388 if (!CBS_stow(&ticket, &s->tlsext_tick, &s->tlsext_ticklen)) 389 goto err; 390 } 391 392 /* Compression method [11]. */ 393 /* SRP username [12]. */ 394 395 *pp = CBS_data(&cbs); 396 397 if (a != NULL) 398 *a = s; 399 400 return (s); 401 402 err: 403 ERR_asprintf_error_data("offset=%d", (int)(CBS_data(&cbs) - *pp)); 404 405 if (s != NULL && (a == NULL || *a != s)) 406 SSL_SESSION_free(s); 407 408 return (NULL); 409 } 410 LSSL_ALIAS(d2i_SSL_SESSION); 411