crypto/libressl/tls/tls.c

   1 /* $OpenBSD: tls.c,v 1.94 2022/02/08 19:13:50 tb Exp $ */
   2 /*
   3  * Copyright (c) 2014 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 <sys/socket.h>
  19
  20 #include <errno.h>
  21 #include <limits.h>
  22 #include <pthread.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25
  26 #include <openssl/bio.h>
  27 #include <openssl/err.h>
  28 #include <openssl/evp.h>
  29 #include <openssl/pem.h>
  30 #include <openssl/safestack.h>
  31 #include <openssl/ssl.h>
  32 #include <openssl/x509.h>
  33
  34 #include <tls.h>
  35 #include "tls_internal.h"
  36
  37 static struct tls_config *tls_config_default;
  38
  39 static int tls_init_rv = -1;
  40
  41 static void
  42 tls_do_init(void)
  43 {
  44         OPENSSL_init_ssl(OPENSSL_INIT_NO_LOAD_CONFIG, NULL);
  45
  46         if (BIO_sock_init() != 1)
  47                 return;
  48
  49         if ((tls_config_default = tls_config_new_internal()) == NULL)
  50                 return;
  51
  52         tls_config_default->refcount++;
  53
  54         tls_init_rv = 0;
  55 }
  56
  57 int
  58 tls_init(void)
  59 {
  60         static pthread_once_t once = PTHREAD_ONCE_INIT;
  61
  62         if (pthread_once(&once, tls_do_init) != 0)
  63                 return -1;
  64
  65         return tls_init_rv;
  66 }
  67
  68 const char *
  69 tls_error(struct tls *ctx)
  70 {
  71         return ctx->error.msg;
  72 }
  73
  74 void
  75 tls_error_clear(struct tls_error *error)
  76 {
  77         free(error->msg);
  78         error->msg = NULL;
  79         error->num = 0;
  80         error->tls = 0;
  81 }
  82
  83 static int
  84 tls_error_vset(struct tls_error *error, int errnum, const char *fmt, va_list ap)
  85 {
  86         char *errmsg = NULL;
  87         int rv = -1;
  88
  89         tls_error_clear(error);
  90
  91         error->num = errnum;
  92         error->tls = 1;
  93
  94         if (vasprintf(&errmsg, fmt, ap) == -1) {
  95                 errmsg = NULL;
  96                 goto err;
  97         }
  98
  99         if (errnum == -1) {
 100                 error->msg = errmsg;
 101                 return (0);
 102         }
 103
 104         if (asprintf(&error->msg, "%s: %s", errmsg, strerror(errnum)) == -1) {
 105                 error->msg = NULL;
 106                 goto err;
 107         }
 108         rv = 0;
 109
 110  err:
 111         free(errmsg);
 112
 113         return (rv);
 114 }
 115
 116 int
 117 tls_error_set(struct tls_error *error, const char *fmt, ...)
 118 {
 119         va_list ap;
 120         int errnum, rv;
 121
 122         errnum = errno;
 123
 124         va_start(ap, fmt);
 125         rv = tls_error_vset(error, errnum, fmt, ap);
 126         va_end(ap);
 127
 128         return (rv);
 129 }
 130
 131 int
 132 tls_error_setx(struct tls_error *error, const char *fmt, ...)
 133 {
 134         va_list ap;
 135         int rv;
 136
 137         va_start(ap, fmt);
 138         rv = tls_error_vset(error, -1, fmt, ap);
 139         va_end(ap);
 140
 141         return (rv);
 142 }
 143
 144 int
 145 tls_config_set_error(struct tls_config *config, const char *fmt, ...)
 146 {
 147         va_list ap;
 148         int errnum, rv;
 149
 150         errnum = errno;
 151
 152         va_start(ap, fmt);
 153         rv = tls_error_vset(&config->error, errnum, fmt, ap);
 154         va_end(ap);
 155
 156         return (rv);
 157 }
 158
 159 int
 160 tls_config_set_errorx(struct tls_config *config, const char *fmt, ...)
 161 {
 162         va_list ap;
 163         int rv;
 164
 165         va_start(ap, fmt);
 166         rv = tls_error_vset(&config->error, -1, fmt, ap);
 167         va_end(ap);
 168
 169         return (rv);
 170 }
 171
 172 int
 173 tls_set_error(struct tls *ctx, const char *fmt, ...)
 174 {
 175         va_list ap;
 176         int errnum, rv;
 177
 178         errnum = errno;
 179
 180         va_start(ap, fmt);
 181         rv = tls_error_vset(&ctx->error, errnum, fmt, ap);
 182         va_end(ap);
 183
 184         return (rv);
 185 }
 186
 187 int
 188 tls_set_errorx(struct tls *ctx, const char *fmt, ...)
 189 {
 190         va_list ap;
 191         int rv;
 192
 193         va_start(ap, fmt);
 194         rv = tls_error_vset(&ctx->error, -1, fmt, ap);
 195         va_end(ap);
 196
 197         return (rv);
 198 }
 199
 200 int
 201 tls_set_ssl_errorx(struct tls *ctx, const char *fmt, ...)
 202 {
 203         va_list ap;
 204         int rv;
 205
 206         /* Only set an error if a more specific one does not already exist. */
 207         if (ctx->error.tls != 0)
 208                 return (0);
 209
 210         va_start(ap, fmt);
 211         rv = tls_error_vset(&ctx->error, -1, fmt, ap);
 212         va_end(ap);
 213
 214         return (rv);
 215 }
 216
 217 struct tls_sni_ctx *
 218 tls_sni_ctx_new(void)
 219 {
 220         return (calloc(1, sizeof(struct tls_sni_ctx)));
 221 }
 222
 223 void
 224 tls_sni_ctx_free(struct tls_sni_ctx *sni_ctx)
 225 {
 226         if (sni_ctx == NULL)
 227                 return;
 228
 229         SSL_CTX_free(sni_ctx->ssl_ctx);
 230         X509_free(sni_ctx->ssl_cert);
 231
 232         free(sni_ctx);
 233 }
 234
 235 struct tls *
 236 tls_new(void)
 237 {
 238         struct tls *ctx;
 239
 240         if ((ctx = calloc(1, sizeof(*ctx))) == NULL)
 241                 return (NULL);
 242
 243         tls_reset(ctx);
 244
 245         if (tls_configure(ctx, tls_config_default) == -1) {
 246                 free(ctx);
 247                 return NULL;
 248         }
 249
 250         return (ctx);
 251 }
 252
 253 int
 254 tls_configure(struct tls *ctx, struct tls_config *config)
 255 {
 256         if (config == NULL)
 257                 config = tls_config_default;
 258
 259         pthread_mutex_lock(&config->mutex);
 260         config->refcount++;
 261         pthread_mutex_unlock(&config->mutex);
 262
 263         tls_config_free(ctx->config);
 264
 265         ctx->config = config;
 266         ctx->keypair = config->keypair;
 267
 268         if ((ctx->flags & TLS_SERVER) != 0)
 269                 return (tls_configure_server(ctx));
 270
 271         return (0);
 272 }
 273
 274 int
 275 tls_cert_hash(X509 *cert, char **hash)
 276 {
 277         char d[EVP_MAX_MD_SIZE], *dhex = NULL;
 278         int dlen, rv = -1;
 279
 280         free(*hash);
 281         *hash = NULL;
 282
 283         if (X509_digest(cert, EVP_sha256(), d, &dlen) != 1)
 284                 goto err;
 285
 286         if (tls_hex_string(d, dlen, &dhex, NULL) != 0)
 287                 goto err;
 288
 289         if (asprintf(hash, "SHA256:%s", dhex) == -1) {
 290                 *hash = NULL;
 291                 goto err;
 292         }
 293
 294         rv = 0;
 295  err:
 296         free(dhex);
 297
 298         return (rv);
 299 }
 300
 301 int
 302 tls_cert_pubkey_hash(X509 *cert, char **hash)
 303 {
 304         char d[EVP_MAX_MD_SIZE], *dhex = NULL;
 305         int dlen, rv = -1;
 306
 307         free(*hash);
 308         *hash = NULL;
 309
 310         if (X509_pubkey_digest(cert, EVP_sha256(), d, &dlen) != 1)
 311                 goto err;
 312
 313         if (tls_hex_string(d, dlen, &dhex, NULL) != 0)
 314                 goto err;
 315
 316         if (asprintf(hash, "SHA256:%s", dhex) == -1) {
 317                 *hash = NULL;
 318                 goto err;
 319         }
 320
 321         rv = 0;
 322
 323  err:
 324         free(dhex);
 325
 326         return (rv);
 327 }
 328
 329 static int
 330 tls_keypair_to_pkey(struct tls *ctx, struct tls_keypair *keypair, EVP_PKEY **pkey)
 331 {
 332         BIO *bio = NULL;
 333         X509 *x509 = NULL;
 334         char *mem;
 335         size_t len;
 336         int ret = -1;
 337
 338         *pkey = NULL;
 339
 340         if (ctx->config->use_fake_private_key) {
 341                 mem = keypair->cert_mem;
 342                 len = keypair->cert_len;
 343         } else {
 344                 mem = keypair->key_mem;
 345                 len = keypair->key_len;
 346         }
 347
 348         if (mem == NULL)
 349                 return (0);
 350
 351         if (len > INT_MAX) {
 352                 tls_set_errorx(ctx, ctx->config->use_fake_private_key ?
 353                     "cert too long" : "key too long");
 354                 goto err;
 355         }
 356
 357         if ((bio = BIO_new_mem_buf(mem, len)) == NULL) {
 358                 tls_set_errorx(ctx, "failed to create buffer");
 359                 goto err;
 360         }
 361
 362         if (ctx->config->use_fake_private_key) {
 363                 if ((x509 = PEM_read_bio_X509(bio, NULL, tls_password_cb,
 364                     NULL)) == NULL) {
 365                         tls_set_errorx(ctx, "failed to read X509 certificate");
 366                         goto err;
 367                 }
 368                 if ((*pkey = X509_get_pubkey(x509)) == NULL) {
 369                         tls_set_errorx(ctx, "failed to retrieve pubkey");
 370                         goto err;
 371                 }
 372         } else {
 373                 if ((*pkey = PEM_read_bio_PrivateKey(bio, NULL, tls_password_cb,
 374                     NULL)) ==  NULL) {
 375                         tls_set_errorx(ctx, "failed to read private key");
 376                         goto err;
 377                 }
 378         }
 379
 380         ret = 0;
 381  err:
 382         BIO_free(bio);
 383         X509_free(x509);
 384         return (ret);
 385 }
 386
 387 static int
 388 tls_keypair_setup_pkey(struct tls *ctx, struct tls_keypair *keypair, EVP_PKEY *pkey)
 389 {
 390         RSA_METHOD *rsa_method;
 391         ECDSA_METHOD *ecdsa_method;
 392         RSA *rsa = NULL;
 393         EC_KEY *eckey = NULL;
 394         int ret = -1;
 395
 396         /* Only install the pubkey hash if fake private keys are used. */
 397         if (!ctx->config->skip_private_key_check)
 398                 return (0);
 399
 400         if (keypair->pubkey_hash == NULL) {
 401                 tls_set_errorx(ctx, "public key hash not set");
 402                 goto err;
 403         }
 404
 405         switch (EVP_PKEY_id(pkey)) {
 406         case EVP_PKEY_RSA:
 407                 if ((rsa = EVP_PKEY_get1_RSA(pkey)) == NULL ||
 408                     RSA_set_ex_data(rsa, 0, keypair->pubkey_hash) == 0) {
 409                         tls_set_errorx(ctx, "RSA key setup failure");
 410                         goto err;
 411                 }
 412                 if (ctx->config->sign_cb == NULL)
 413                         break;
 414                 if ((rsa_method = tls_signer_rsa_method()) == NULL ||
 415                     RSA_set_ex_data(rsa, 1, ctx->config) == 0 ||
 416                     RSA_set_method(rsa, rsa_method) == 0) {
 417                         tls_set_errorx(ctx, "failed to setup RSA key");
 418                         goto err;
 419                 }
 420                 break;
 421         case EVP_PKEY_EC:
 422                 if ((eckey = EVP_PKEY_get1_EC_KEY(pkey)) == NULL ||
 423                     ECDSA_set_ex_data(eckey, 0, keypair->pubkey_hash) == 0) {
 424                         tls_set_errorx(ctx, "EC key setup failure");
 425                         goto err;
 426                 }
 427                 if (ctx->config->sign_cb == NULL)
 428                         break;
 429                 if ((ecdsa_method = tls_signer_ecdsa_method()) == NULL ||
 430                     ECDSA_set_ex_data(eckey, 1, ctx->config) == 0 ||
 431                     ECDSA_set_method(eckey, ecdsa_method) == 0) {
 432                         tls_set_errorx(ctx, "failed to setup EC key");
 433                         goto err;
 434                 }
 435                 break;
 436         default:
 437                 tls_set_errorx(ctx, "incorrect key type");
 438                 goto err;
 439         }
 440
 441         ret = 0;
 442
 443  err:
 444         RSA_free(rsa);
 445         EC_KEY_free(eckey);
 446         return (ret);
 447 }
 448
 449 int
 450 tls_configure_ssl_keypair(struct tls *ctx, SSL_CTX *ssl_ctx,
 451     struct tls_keypair *keypair, int required)
 452 {
 453         EVP_PKEY *pkey = NULL;
 454
 455         if (!required &&
 456             keypair->cert_mem == NULL &&
 457             keypair->key_mem == NULL)
 458                 return(0);
 459
 460         if (keypair->cert_mem != NULL) {
 461                 if (keypair->cert_len > INT_MAX) {
 462                         tls_set_errorx(ctx, "certificate too long");
 463                         goto err;
 464                 }
 465
 466                 if (SSL_CTX_use_certificate_chain_mem(ssl_ctx,
 467                     keypair->cert_mem, keypair->cert_len) != 1) {
 468                         tls_set_errorx(ctx, "failed to load certificate");
 469                         goto err;
 470                 }
 471         }
 472
 473         if (tls_keypair_to_pkey(ctx, keypair, &pkey) == -1)
 474                 goto err;
 475         if (pkey != NULL) {
 476                 if (tls_keypair_setup_pkey(ctx, keypair, pkey) == -1)
 477                         goto err;
 478                 if (SSL_CTX_use_PrivateKey(ssl_ctx, pkey) != 1) {
 479                         tls_set_errorx(ctx, "failed to load private key");
 480                         goto err;
 481                 }
 482                 EVP_PKEY_free(pkey);
 483                 pkey = NULL;
 484         }
 485
 486         if (!ctx->config->skip_private_key_check &&
 487             SSL_CTX_check_private_key(ssl_ctx) != 1) {
 488                 tls_set_errorx(ctx, "private/public key mismatch");
 489                 goto err;
 490         }
 491
 492         return (0);
 493
 494  err:
 495         EVP_PKEY_free(pkey);
 496
 497         return (-1);
 498 }
 499
 500 int
 501 tls_configure_ssl(struct tls *ctx, SSL_CTX *ssl_ctx)
 502 {
 503         SSL_CTX_clear_mode(ssl_ctx, SSL_MODE_AUTO_RETRY);
 504
 505         SSL_CTX_set_mode(ssl_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
 506         SSL_CTX_set_mode(ssl_ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 507
 508         SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_SSLv2);
 509         SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_SSLv3);
 510
 511         SSL_CTX_clear_options(ssl_ctx, SSL_OP_NO_TLSv1);
 512         SSL_CTX_clear_options(ssl_ctx, SSL_OP_NO_TLSv1_1);
 513         SSL_CTX_clear_options(ssl_ctx, SSL_OP_NO_TLSv1_2);
 514         SSL_CTX_clear_options(ssl_ctx, SSL_OP_NO_TLSv1_3);
 515
 516         if ((ctx->config->protocols & TLS_PROTOCOL_TLSv1_0) == 0)
 517                 SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_TLSv1);
 518         if ((ctx->config->protocols & TLS_PROTOCOL_TLSv1_1) == 0)
 519                 SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_TLSv1_1);
 520         if ((ctx->config->protocols & TLS_PROTOCOL_TLSv1_2) == 0)
 521                 SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_TLSv1_2);
 522         if ((ctx->config->protocols & TLS_PROTOCOL_TLSv1_3) == 0)
 523                 SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_TLSv1_3);
 524
 525         if (ctx->config->alpn != NULL) {
 526                 if (SSL_CTX_set_alpn_protos(ssl_ctx, ctx->config->alpn,
 527                     ctx->config->alpn_len) != 0) {
 528                         tls_set_errorx(ctx, "failed to set alpn");
 529                         goto err;
 530                 }
 531         }
 532
 533         if (ctx->config->ciphers != NULL) {
 534                 if (SSL_CTX_set_cipher_list(ssl_ctx,
 535                     ctx->config->ciphers) != 1) {
 536                         tls_set_errorx(ctx, "failed to set ciphers");
 537                         goto err;
 538                 }
 539         }
 540
 541         if (ctx->config->verify_time == 0) {
 542                 X509_VERIFY_PARAM_set_flags(SSL_CTX_get0_param(ssl_ctx),
 543                     X509_V_FLAG_NO_CHECK_TIME);
 544         }
 545
 546         /* Disable any form of session caching by default */
 547         SSL_CTX_set_session_cache_mode(ssl_ctx, SSL_SESS_CACHE_OFF);
 548         SSL_CTX_set_options(ssl_ctx, SSL_OP_NO_TICKET);
 549
 550         return (0);
 551
 552  err:
 553         return (-1);
 554 }
 555
 556 static int
 557 tls_ssl_cert_verify_cb(X509_STORE_CTX *x509_ctx, void *arg)
 558 {
 559         struct tls *ctx = arg;
 560         int x509_err;
 561
 562         if (ctx->config->verify_cert == 0)
 563                 return (1);
 564
 565         if ((X509_verify_cert(x509_ctx)) < 0) {
 566                 tls_set_errorx(ctx, "X509 verify cert failed");
 567                 return (0);
 568         }
 569
 570         x509_err = X509_STORE_CTX_get_error(x509_ctx);
 571         if (x509_err == X509_V_OK)
 572                 return (1);
 573
 574         tls_set_errorx(ctx, "certificate verification failed: %s",
 575             X509_verify_cert_error_string(x509_err));
 576
 577         return (0);
 578 }
 579
 580 int
 581 tls_configure_ssl_verify(struct tls *ctx, SSL_CTX *ssl_ctx, int verify)
 582 {
 583         size_t ca_len = ctx->config->ca_len;
 584         char *ca_mem = ctx->config->ca_mem;
 585         char *crl_mem = ctx->config->crl_mem;
 586         size_t crl_len = ctx->config->crl_len;
 587         char *ca_free = NULL;
 588         STACK_OF(X509_INFO) *xis = NULL;
 589         X509_STORE *store;
 590         X509_INFO *xi;
 591         BIO *bio = NULL;
 592         int rv = -1;
 593         int i;
 594
 595         SSL_CTX_set_verify(ssl_ctx, verify, NULL);
 596         SSL_CTX_set_cert_verify_callback(ssl_ctx, tls_ssl_cert_verify_cb, ctx);
 597
 598         if (ctx->config->verify_depth >= 0)
 599                 SSL_CTX_set_verify_depth(ssl_ctx, ctx->config->verify_depth);
 600
 601         if (ctx->config->verify_cert == 0)
 602                 goto done;
 603
 604         /* If no CA has been specified, attempt to load the default. */
 605         if (ctx->config->ca_mem == NULL && ctx->config->ca_path == NULL) {
 606                 if (tls_config_load_file(&ctx->error, "CA", tls_default_ca_cert_file(),
 607                     &ca_mem, &ca_len) != 0)
 608                         goto err;
 609                 ca_free = ca_mem;
 610         }
 611
 612         if (ca_mem != NULL) {
 613                 if (ca_len > INT_MAX) {
 614                         tls_set_errorx(ctx, "ca too long");
 615                         goto err;
 616                 }
 617                 if (SSL_CTX_load_verify_mem(ssl_ctx, ca_mem, ca_len) != 1) {
 618                         tls_set_errorx(ctx, "ssl verify memory setup failure");
 619                         goto err;
 620                 }
 621         } else if (SSL_CTX_load_verify_locations(ssl_ctx, NULL,
 622             ctx->config->ca_path) != 1) {
 623                 tls_set_errorx(ctx, "ssl verify locations failure");
 624                 goto err;
 625         }
 626
 627         if (crl_mem != NULL) {
 628                 if (crl_len > INT_MAX) {
 629                         tls_set_errorx(ctx, "crl too long");
 630                         goto err;
 631                 }
 632                 if ((bio = BIO_new_mem_buf(crl_mem, crl_len)) == NULL) {
 633                         tls_set_errorx(ctx, "failed to create buffer");
 634                         goto err;
 635                 }
 636                 if ((xis = PEM_X509_INFO_read_bio(bio, NULL, tls_password_cb,
 637                     NULL)) == NULL) {
 638                         tls_set_errorx(ctx, "failed to parse crl");
 639                         goto err;
 640                 }
 641                 store = SSL_CTX_get_cert_store(ssl_ctx);
 642                 for (i = 0; i < sk_X509_INFO_num(xis); i++) {
 643                         xi = sk_X509_INFO_value(xis, i);
 644                         if (xi->crl == NULL)
 645                                 continue;
 646                         if (!X509_STORE_add_crl(store, xi->crl)) {
 647                                 tls_set_error(ctx, "failed to add crl");
 648                                 goto err;
 649                         }
 650                 }
 651                 X509_STORE_set_flags(store,
 652                     X509_V_FLAG_CRL_CHECK | X509_V_FLAG_CRL_CHECK_ALL);
 653         }
 654
 655  done:
 656         rv = 0;
 657
 658  err:
 659         sk_X509_INFO_pop_free(xis, X509_INFO_free);
 660         BIO_free(bio);
 661         free(ca_free);
 662
 663         return (rv);
 664 }
 665
 666 void
 667 tls_free(struct tls *ctx)
 668 {
 669         if (ctx == NULL)
 670                 return;
 671
 672         tls_reset(ctx);
 673
 674         free(ctx);
 675 }
 676
 677 void
 678 tls_reset(struct tls *ctx)
 679 {
 680         struct tls_sni_ctx *sni, *nsni;
 681
 682         tls_config_free(ctx->config);
 683         ctx->config = NULL;
 684
 685         SSL_CTX_free(ctx->ssl_ctx);
 686         SSL_free(ctx->ssl_conn);
 687         X509_free(ctx->ssl_peer_cert);
 688
 689         ctx->ssl_conn = NULL;
 690         ctx->ssl_ctx = NULL;
 691         ctx->ssl_peer_cert = NULL;
 692         /* X509 objects in chain are freed with the SSL */
 693         ctx->ssl_peer_chain = NULL;
 694
 695         ctx->socket = -1;
 696         ctx->state = 0;
 697
 698         free(ctx->servername);
 699         ctx->servername = NULL;
 700
 701         free(ctx->error.msg);
 702         ctx->error.msg = NULL;
 703         ctx->error.num = -1;
 704
 705         tls_conninfo_free(ctx->conninfo);
 706         ctx->conninfo = NULL;
 707
 708         tls_ocsp_free(ctx->ocsp);
 709         ctx->ocsp = NULL;
 710
 711         for (sni = ctx->sni_ctx; sni != NULL; sni = nsni) {
 712                 nsni = sni->next;
 713                 tls_sni_ctx_free(sni);
 714         }
 715         ctx->sni_ctx = NULL;
 716
 717         ctx->read_cb = NULL;
 718         ctx->write_cb = NULL;
 719         ctx->cb_arg = NULL;
 720 }
 721
 722 int
 723 tls_ssl_error(struct tls *ctx, SSL *ssl_conn, int ssl_ret, const char *prefix)
 724 {
 725         const char *errstr = "unknown error";
 726         unsigned long err;
 727         int ssl_err;
 728
 729         ssl_err = SSL_get_error(ssl_conn, ssl_ret);
 730         switch (ssl_err) {
 731         case SSL_ERROR_NONE:
 732         case SSL_ERROR_ZERO_RETURN:
 733                 return (0);
 734
 735         case SSL_ERROR_WANT_READ:
 736                 return (TLS_WANT_POLLIN);
 737
 738         case SSL_ERROR_WANT_WRITE:
 739                 return (TLS_WANT_POLLOUT);
 740
 741         case SSL_ERROR_SYSCALL:
 742                 if ((err = ERR_peek_error()) != 0) {
 743                         errstr = ERR_error_string(err, NULL);
 744                 } else if (ssl_ret == 0) {
 745                         if ((ctx->state & TLS_HANDSHAKE_COMPLETE) != 0) {
 746                                 ctx->state |= TLS_EOF_NO_CLOSE_NOTIFY;
 747                                 return (0);
 748                         }
 749                         errstr = "unexpected EOF";
 750                 } else if (ssl_ret == -1) {
 751                         errstr = strerror(errno);
 752                 }
 753                 tls_set_ssl_errorx(ctx, "%s failed: %s", prefix, errstr);
 754                 return (-1);
 755
 756         case SSL_ERROR_SSL:
 757                 if ((err = ERR_peek_error()) != 0) {
 758                         errstr = ERR_error_string(err, NULL);
 759                 }
 760                 tls_set_ssl_errorx(ctx, "%s failed: %s", prefix, errstr);
 761                 return (-1);
 762
 763         case SSL_ERROR_WANT_CONNECT:
 764         case SSL_ERROR_WANT_ACCEPT:
 765         case SSL_ERROR_WANT_X509_LOOKUP:
 766         default:
 767                 tls_set_ssl_errorx(ctx, "%s failed (%d)", prefix, ssl_err);
 768                 return (-1);
 769         }
 770 }
 771
 772 int
 773 tls_handshake(struct tls *ctx)
 774 {
 775         int rv = -1;
 776
 777         tls_error_clear(&ctx->error);
 778
 779         if ((ctx->flags & (TLS_CLIENT | TLS_SERVER_CONN)) == 0) {
 780                 tls_set_errorx(ctx, "invalid operation for context");
 781                 goto out;
 782         }
 783
 784         if ((ctx->state & TLS_HANDSHAKE_COMPLETE) != 0) {
 785                 tls_set_errorx(ctx, "handshake already completed");
 786                 goto out;
 787         }
 788
 789         if ((ctx->flags & TLS_CLIENT) != 0)
 790                 rv = tls_handshake_client(ctx);
 791         else if ((ctx->flags & TLS_SERVER_CONN) != 0)
 792                 rv = tls_handshake_server(ctx);
 793
 794         if (rv == 0) {
 795                 ctx->ssl_peer_cert = SSL_get_peer_certificate(ctx->ssl_conn);
 796                 ctx->ssl_peer_chain = SSL_get_peer_cert_chain(ctx->ssl_conn);
 797                 if (tls_conninfo_populate(ctx) == -1)
 798                         rv = -1;
 799                 if (ctx->ocsp == NULL)
 800                         ctx->ocsp = tls_ocsp_setup_from_peer(ctx);
 801         }
 802  out:
 803         /* Prevent callers from performing incorrect error handling */
 804         errno = 0;
 805         return (rv);
 806 }
 807
 808 ssize_t
 809 tls_read(struct tls *ctx, void *buf, size_t buflen)
 810 {
 811         ssize_t rv = -1;
 812         int ssl_ret;
 813
 814         tls_error_clear(&ctx->error);
 815
 816         if ((ctx->state & TLS_HANDSHAKE_COMPLETE) == 0) {
 817                 if ((rv = tls_handshake(ctx)) != 0)
 818                         goto out;
 819         }
 820
 821         if (buflen > INT_MAX) {
 822                 tls_set_errorx(ctx, "buflen too long");
 823                 goto out;
 824         }
 825
 826         ERR_clear_error();
 827         if ((ssl_ret = SSL_read(ctx->ssl_conn, buf, buflen)) > 0) {
 828                 rv = (ssize_t)ssl_ret;
 829                 goto out;
 830         }
 831         rv = (ssize_t)tls_ssl_error(ctx, ctx->ssl_conn, ssl_ret, "read");
 832
 833  out:
 834         /* Prevent callers from performing incorrect error handling */
 835         errno = 0;
 836         return (rv);
 837 }
 838
 839 ssize_t
 840 tls_write(struct tls *ctx, const void *buf, size_t buflen)
 841 {
 842         ssize_t rv = -1;
 843         int ssl_ret;
 844
 845         tls_error_clear(&ctx->error);
 846
 847         if ((ctx->state & TLS_HANDSHAKE_COMPLETE) == 0) {
 848                 if ((rv = tls_handshake(ctx)) != 0)
 849                         goto out;
 850         }
 851
 852         if (buflen > INT_MAX) {
 853                 tls_set_errorx(ctx, "buflen too long");
 854                 goto out;
 855         }
 856
 857         ERR_clear_error();
 858         if ((ssl_ret = SSL_write(ctx->ssl_conn, buf, buflen)) > 0) {
 859                 rv = (ssize_t)ssl_ret;
 860                 goto out;
 861         }
 862         rv = (ssize_t)tls_ssl_error(ctx, ctx->ssl_conn, ssl_ret, "write");
 863
 864  out:
 865         /* Prevent callers from performing incorrect error handling */
 866         errno = 0;
 867         return (rv);
 868 }
 869
 870 int
 871 tls_close(struct tls *ctx)
 872 {
 873         int ssl_ret;
 874         int rv = 0;
 875
 876         tls_error_clear(&ctx->error);
 877
 878         if ((ctx->flags & (TLS_CLIENT | TLS_SERVER_CONN)) == 0) {
 879                 tls_set_errorx(ctx, "invalid operation for context");
 880                 rv = -1;
 881                 goto out;
 882         }
 883
 884         if (ctx->state & TLS_SSL_NEEDS_SHUTDOWN) {
 885                 ERR_clear_error();
 886                 ssl_ret = SSL_shutdown(ctx->ssl_conn);
 887                 if (ssl_ret < 0) {
 888                         rv = tls_ssl_error(ctx, ctx->ssl_conn, ssl_ret,
 889                             "shutdown");
 890                         if (rv == TLS_WANT_POLLIN || rv == TLS_WANT_POLLOUT)
 891                                 goto out;
 892                 }
 893                 ctx->state &= ~TLS_SSL_NEEDS_SHUTDOWN;
 894         }
 895
 896         if (ctx->socket != -1) {
 897                 if (shutdown(ctx->socket, SHUT_RDWR) != 0) {
 898                         if (rv == 0 &&
 899                             errno != ENOTCONN && errno != ECONNRESET) {
 900                                 tls_set_error(ctx, "shutdown");
 901                                 rv = -1;
 902                         }
 903                 }
 904                 if (close(ctx->socket) != 0) {
 905                         if (rv == 0) {
 906                                 tls_set_error(ctx, "close");
 907                                 rv = -1;
 908                         }
 909                 }
 910                 ctx->socket = -1;
 911         }
 912
 913         if ((ctx->state & TLS_EOF_NO_CLOSE_NOTIFY) != 0) {
 914                 tls_set_errorx(ctx, "EOF without close notify");
 915                 rv = -1;
 916         }
 917
 918  out:
 919         /* Prevent callers from performing incorrect error handling */
 920         errno = 0;
 921         return (rv);
 922 }