main/tcptls.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2007 - 2008, Digium, Inc.
   5  *
   6  * Luigi Rizzo (TCP and TLS server code)
   7  * Brett Bryant <brettbryant@gmail.com> (updated for client support)
   8  *
   9  * See http://www.asterisk.org for more information about
  10  * the Asterisk project. Please do not directly contact
  11  * any of the maintainers of this project for assistance;
  12  * the project provides a web site, mailing lists and IRC
  13  * channels for your use.
  14  *
  15  * This program is free software, distributed under the terms of
  16  * the GNU General Public License Version 2. See the LICENSE file
  17  * at the top of the source tree.
  18  */
  19
  20 /*!
  21  * \file
  22  * \brief Code to support TCP and TLS server/client
  23  *
  24  * \author Luigi Rizzo
  25  * \author Brett Bryant <brettbryant@gmail.com>
  26  */
  27
  28 #include "asterisk.h"
  29
  30 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  31
  32 #ifdef HAVE_FCNTL_H
  33 #include <fcntl.h>
  34 #endif
  35
  36 #include <signal.h>
  37 #include <sys/signal.h>
  38
  39 #include "asterisk/compat.h"
  40 #include "asterisk/tcptls.h"
  41 #include "asterisk/http.h"
  42 #include "asterisk/utils.h"
  43 #include "asterisk/strings.h"
  44 #include "asterisk/options.h"
  45 #include "asterisk/manager.h"
  46 #include "asterisk/astobj2.h"
  47
  48 /*! \brief
  49  * replacement read/write functions for SSL support.
  50  * We use wrappers rather than SSL_read/SSL_write directly so
  51  * we can put in some debugging.
  52  */
  53
  54 #ifdef DO_SSL
  55 static HOOK_T ssl_read(void *cookie, char *buf, LEN_T len)
  56 {
  57         int i = SSL_read(cookie, buf, len-1);
  58 #if 0
  59         if (i >= 0)
  60                 buf[i] = '\0';
  61         ast_verb(0, "ssl read size %d returns %d <%s>\n", (int)len, i, buf);
  62 #endif
  63         return i;
  64 }
  65
  66 static HOOK_T ssl_write(void *cookie, const char *buf, LEN_T len)
  67 {
  68 #if 0
  69         char *s = alloca(len+1);
  70         strncpy(s, buf, len);
  71         s[len] = '\0';
  72         ast_verb(0, "ssl write size %d <%s>\n", (int)len, s);
  73 #endif
  74         return SSL_write(cookie, buf, len);
  75 }
  76
  77 static int ssl_close(void *cookie)
  78 {
  79         close(SSL_get_fd(cookie));
  80         SSL_shutdown(cookie);
  81         SSL_free(cookie);
  82         return 0;
  83 }
  84 #endif  /* DO_SSL */
  85
  86 HOOK_T ast_tcptls_server_read(struct ast_tcptls_session_instance *tcptls_session, void *buf, size_t count)
  87 {
  88         if (tcptls_session->fd == -1) {
  89                 ast_log(LOG_ERROR, "server_read called with an fd of -1\n");
  90                 errno = EIO;
  91                 return -1;
  92         }
  93
  94 #ifdef DO_SSL
  95         if (tcptls_session->ssl)
  96                 return ssl_read(tcptls_session->ssl, buf, count);
  97 #endif
  98         return read(tcptls_session->fd, buf, count);
  99 }
 100
 101 HOOK_T ast_tcptls_server_write(struct ast_tcptls_session_instance *tcptls_session, const void *buf, size_t count)
 102 {
 103         if (tcptls_session->fd == -1) {
 104                 ast_log(LOG_ERROR, "server_write called with an fd of -1\n");
 105                 errno = EIO;
 106                 return -1;
 107         }
 108
 109 #ifdef DO_SSL
 110         if (tcptls_session->ssl)
 111                 return ssl_write(tcptls_session->ssl, buf, count);
 112 #endif
 113         return write(tcptls_session->fd, buf, count);
 114 }
 115
 116 static void session_instance_destructor(void *obj)
 117 {
 118         struct ast_tcptls_session_instance *i = obj;
 119         ast_mutex_destroy(&i->lock);
 120 }
 121
 122 /*! \brief
 123 * creates a FILE * from the fd passed by the accept thread.
 124 * This operation is potentially expensive (certificate verification),
 125 * so we do it in the child thread context.
 126 *
 127 * \note must decrement ref count before returning NULL on error
 128 */
 129 static void *handle_tcptls_connection(void *data)
 130 {
 131         struct ast_tcptls_session_instance *tcptls_session = data;
 132 #ifdef DO_SSL
 133         int (*ssl_setup)(SSL *) = (tcptls_session->client) ? SSL_connect : SSL_accept;
 134         int ret;
 135         char err[256];
 136 #endif
 137
 138         /*
 139         * open a FILE * as appropriate.
 140         */
 141         if (!tcptls_session->parent->tls_cfg) {
 142                 tcptls_session->f = fdopen(tcptls_session->fd, "w+");
 143                 setvbuf(tcptls_session->f, NULL, _IONBF, 0);
 144         }
 145 #ifdef DO_SSL
 146         else if ( (tcptls_session->ssl = SSL_new(tcptls_session->parent->tls_cfg->ssl_ctx)) ) {
 147                 SSL_set_fd(tcptls_session->ssl, tcptls_session->fd);
 148                 if ((ret = ssl_setup(tcptls_session->ssl)) <= 0) {
 149                         ast_verb(2, "Problem setting up ssl connection: %s\n", ERR_error_string(ERR_get_error(), err));
 150                 } else {
 151 #if defined(HAVE_FUNOPEN)       /* the BSD interface */
 152                         tcptls_session->f = funopen(tcptls_session->ssl, ssl_read, ssl_write, NULL, ssl_close);
 153
 154 #elif defined(HAVE_FOPENCOOKIE) /* the glibc/linux interface */
 155                         static const cookie_io_functions_t cookie_funcs = {
 156                                 ssl_read, ssl_write, NULL, ssl_close
 157                         };
 158                         tcptls_session->f = fopencookie(tcptls_session->ssl, "w+", cookie_funcs);
 159 #else
 160                         /* could add other methods here */
 161                         ast_debug(2, "no tcptls_session->f methods attempted!");
 162 #endif
 163                         if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
 164                                 || (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
 165                                 X509 *peer;
 166                                 long res;
 167                                 peer = SSL_get_peer_certificate(tcptls_session->ssl);
 168                                 if (!peer)
 169                                         ast_log(LOG_WARNING, "No peer SSL certificate\n");
 170                                 res = SSL_get_verify_result(tcptls_session->ssl);
 171                                 if (res != X509_V_OK)
 172                                         ast_log(LOG_ERROR, "Certificate did not verify: %s\n", X509_verify_cert_error_string(res));
 173                                 if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
 174                                         ASN1_STRING *str;
 175                                         unsigned char *str2;
 176                                         X509_NAME *name = X509_get_subject_name(peer);
 177                                         int pos = -1;
 178                                         int found = 0;
 179
 180                                         for (;;) {
 181                                                 /* Walk the certificate to check all available "Common Name" */
 182                                                 /* XXX Probably should do a gethostbyname on the hostname and compare that as well */
 183                                                 pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
 184                                                 if (pos < 0)
 185                                                         break;
 186                                                 str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
 187                                                 ASN1_STRING_to_UTF8(&str2, str);
 188                                                 if (str2) {
 189                                                         if (!strcasecmp(tcptls_session->parent->hostname, (char *) str2))
 190                                                                 found = 1;
 191                                                         ast_debug(3, "SSL Common Name compare s1='%s' s2='%s'\n", tcptls_session->parent->hostname, str2);
 192                                                         OPENSSL_free(str2);
 193                                                 }
 194                                                 if (found)
 195                                                         break;
 196                                         }
 197                                         if (!found) {
 198                                                 ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
 199                                                 if (peer)
 200                                                         X509_free(peer);
 201                                                 close(tcptls_session->fd);
 202                                                 fclose(tcptls_session->f);
 203                                                 ao2_ref(tcptls_session, -1);
 204                                                 return NULL;
 205                                         }
 206                                 }
 207                                 if (peer)
 208                                         X509_free(peer);
 209                         }
 210                 }
 211                 if (!tcptls_session->f) /* no success opening descriptor stacking */
 212                         SSL_free(tcptls_session->ssl);
 213    }
 214 #endif /* DO_SSL */
 215
 216         if (!tcptls_session->f) {
 217                 close(tcptls_session->fd);
 218                 ast_log(LOG_WARNING, "FILE * open failed!\n");
 219 #ifndef DO_SSL
 220                 if (tcptls_session->parent->tls_cfg) {
 221                         ast_log(LOG_WARNING, "Attempted a TLS connection without OpenSSL support.  This will not work!\n");
 222                 }
 223 #endif
 224                 ao2_ref(tcptls_session, -1);
 225                 return NULL;
 226         }
 227
 228         if (tcptls_session && tcptls_session->parent->worker_fn)
 229                 return tcptls_session->parent->worker_fn(tcptls_session);
 230         else
 231                 return tcptls_session;
 232 }
 233
 234 void *ast_tcptls_server_root(void *data)
 235 {
 236         struct ast_tcptls_session_args *desc = data;
 237         int fd;
 238         struct sockaddr_in sin;
 239         socklen_t sinlen;
 240         struct ast_tcptls_session_instance *tcptls_session;
 241         pthread_t launched;
 242
 243         for (;;) {
 244                 int i, flags;
 245
 246                 if (desc->periodic_fn)
 247                         desc->periodic_fn(desc);
 248                 i = ast_wait_for_input(desc->accept_fd, desc->poll_timeout);
 249                 if (i <= 0)
 250                         continue;
 251                 sinlen = sizeof(sin);
 252                 fd = accept(desc->accept_fd, (struct sockaddr *) &sin, &sinlen);
 253                 if (fd < 0) {
 254                         if ((errno != EAGAIN) && (errno != EINTR))
 255                                 ast_log(LOG_WARNING, "Accept failed: %s\n", strerror(errno));
 256                         continue;
 257                 }
 258                 tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor);
 259                 if (!tcptls_session) {
 260                         ast_log(LOG_WARNING, "No memory for new session: %s\n", strerror(errno));
 261                         close(fd);
 262                         continue;
 263                 }
 264
 265                 ast_mutex_init(&tcptls_session->lock);
 266
 267                 flags = fcntl(fd, F_GETFL);
 268                 fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
 269                 tcptls_session->fd = fd;
 270                 tcptls_session->parent = desc;
 271                 memcpy(&tcptls_session->remote_address, &sin, sizeof(tcptls_session->remote_address));
 272
 273                 tcptls_session->client = 0;
 274
 275                 /* This thread is now the only place that controls the single ref to tcptls_session */
 276                 if (ast_pthread_create_detached_background(&launched, NULL, handle_tcptls_connection, tcptls_session)) {
 277                         ast_log(LOG_WARNING, "Unable to launch helper thread: %s\n", strerror(errno));
 278                         close(tcptls_session->fd);
 279                         ao2_ref(tcptls_session, -1);
 280                 }
 281         }
 282         return NULL;
 283 }
 284
 285 static int __ssl_setup(struct ast_tls_config *cfg, int client)
 286 {
 287 #ifndef DO_SSL
 288         cfg->enabled = 0;
 289         return 0;
 290 #else
 291         if (!cfg->enabled)
 292                 return 0;
 293
 294         SSL_load_error_strings();
 295         SSLeay_add_ssl_algorithms();
 296
 297         if (client) {
 298                 if (ast_test_flag(&cfg->flags, AST_SSL_SSLV2_CLIENT)) {
 299                         cfg->ssl_ctx = SSL_CTX_new(SSLv2_client_method());
 300                 } else if (ast_test_flag(&cfg->flags, AST_SSL_SSLV3_CLIENT)) {
 301                         cfg->ssl_ctx = SSL_CTX_new(SSLv3_client_method());
 302                 } else if (ast_test_flag(&cfg->flags, AST_SSL_TLSV1_CLIENT)) {
 303                         cfg->ssl_ctx = SSL_CTX_new(TLSv1_client_method());
 304                 } else {
 305                         /* SSLv23_client_method() sends SSLv2, this was the original
 306                          * default for ssl clients before the option was given to
 307                          * pick what protocol a client should use.  In order not
 308                          * to break expected behavior it remains the default. */
 309                         cfg->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
 310                 }
 311         } else {
 312                 /* SSLv23_server_method() supports TLSv1, SSLv2, and SSLv3 inbound connections. */
 313                 cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());
 314         }
 315
 316         if (!cfg->ssl_ctx) {
 317                 ast_debug(1, "Sorry, SSL_CTX_new call returned null...\n");
 318                 cfg->enabled = 0;
 319                 return 0;
 320         }
 321         if (!ast_strlen_zero(cfg->certfile)) {
 322                 char *tmpprivate = ast_strlen_zero(cfg->pvtfile) ? cfg->certfile : cfg->pvtfile;
 323                 if (SSL_CTX_use_certificate_file(cfg->ssl_ctx, cfg->certfile, SSL_FILETYPE_PEM) == 0) {
 324                         if (!client) {
 325                                 /* Clients don't need a certificate, but if its setup we can use it */
 326                                 ast_verb(0, "SSL error loading cert file. <%s>", cfg->certfile);
 327                                 sleep(2);
 328                                 cfg->enabled = 0;
 329                                 return 0;
 330                         }
 331                 }
 332                 if ((SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, tmpprivate, SSL_FILETYPE_PEM) == 0) || (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0 )) {
 333                         if (!client) {
 334                                 /* Clients don't need a private key, but if its setup we can use it */
 335                                 ast_verb(0, "SSL error loading private key file. <%s>", tmpprivate);
 336                                 sleep(2);
 337                                 cfg->enabled = 0;
 338                                 return 0;
 339                         }
 340                 }
 341         }
 342         if (!ast_strlen_zero(cfg->cipher)) {
 343                 if (SSL_CTX_set_cipher_list(cfg->ssl_ctx, cfg->cipher) == 0 ) {
 344                         if (!client) {
 345                                 ast_verb(0, "SSL cipher error <%s>", cfg->cipher);
 346                                 sleep(2);
 347                                 cfg->enabled = 0;
 348                                 return 0;
 349                         }
 350                 }
 351         }
 352         if (!ast_strlen_zero(cfg->cafile) || !ast_strlen_zero(cfg->capath)) {
 353                 if (SSL_CTX_load_verify_locations(cfg->ssl_ctx, S_OR(cfg->cafile, NULL), S_OR(cfg->capath,NULL)) == 0)
 354                         ast_verb(0, "SSL CA file(%s)/path(%s) error\n", cfg->cafile, cfg->capath);
 355         }
 356
 357         ast_verb(0, "SSL certificate ok\n");
 358         return 1;
 359 #endif
 360 }
 361
 362 int ast_ssl_setup(struct ast_tls_config *cfg)
 363 {
 364         return __ssl_setup(cfg, 0);
 365 }
 366
 367 struct ast_tcptls_session_instance *ast_tcptls_client_start(struct ast_tcptls_session_instance *tcptls_session)
 368 {
 369         struct ast_tcptls_session_args *desc;
 370         int flags;
 371
 372         if (!(desc = tcptls_session->parent)) {
 373                 goto client_start_error;
 374         }
 375
 376         if (connect(desc->accept_fd, (const struct sockaddr *) &desc->remote_address, sizeof(desc->remote_address))) {
 377                 ast_log(LOG_ERROR, "Unable to connect %s to %s:%d: %s\n",
 378                         desc->name,
 379                         ast_inet_ntoa(desc->remote_address.sin_addr), ntohs(desc->remote_address.sin_port),
 380                         strerror(errno));
 381                 goto client_start_error;
 382         }
 383
 384         flags = fcntl(desc->accept_fd, F_GETFL);
 385         fcntl(desc->accept_fd, F_SETFL, flags & ~O_NONBLOCK);
 386
 387         if (desc->tls_cfg) {
 388                 desc->tls_cfg->enabled = 1;
 389                 __ssl_setup(desc->tls_cfg, 1);
 390         }
 391
 392         return handle_tcptls_connection(tcptls_session);
 393
 394 client_start_error:
 395         close(desc->accept_fd);
 396         desc->accept_fd = -1;
 397         if (tcptls_session) {
 398                 ao2_ref(tcptls_session, -1);
 399         }
 400         return NULL;
 401
 402 }
 403
 404 struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_session_args *desc)
 405 {
 406         int x = 1;
 407         struct ast_tcptls_session_instance *tcptls_session = NULL;
 408
 409         /* Do nothing if nothing has changed */
 410         if (!memcmp(&desc->old_address, &desc->remote_address, sizeof(desc->old_address))) {
 411                 ast_debug(1, "Nothing changed in %s\n", desc->name);
 412                 return NULL;
 413         }
 414
 415         desc->old_address = desc->remote_address;
 416
 417         if (desc->accept_fd != -1)
 418                 close(desc->accept_fd);
 419
 420         desc->accept_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 421         if (desc->accept_fd < 0) {
 422                 ast_log(LOG_WARNING, "Unable to allocate socket for %s: %s\n",
 423                         desc->name, strerror(errno));
 424                 return NULL;
 425         }
 426
 427         /* if a local address was specified, bind to it so the connection will
 428            originate from the desired address */
 429         if (desc->local_address.sin_family != 0) {
 430                 setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
 431                 if (bind(desc->accept_fd, (struct sockaddr *) &desc->local_address, sizeof(desc->local_address))) {
 432                         ast_log(LOG_ERROR, "Unable to bind %s to %s:%d: %s\n",
 433                         desc->name,
 434                                 ast_inet_ntoa(desc->local_address.sin_addr), ntohs(desc->local_address.sin_port),
 435                                 strerror(errno));
 436                         goto error;
 437                 }
 438         }
 439
 440         if (!(tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor)))
 441                 goto error;
 442
 443         ast_mutex_init(&tcptls_session->lock);
 444         tcptls_session->client = 1;
 445         tcptls_session->fd = desc->accept_fd;
 446         tcptls_session->parent = desc;
 447         tcptls_session->parent->worker_fn = NULL;
 448         memcpy(&tcptls_session->remote_address, &desc->remote_address, sizeof(tcptls_session->remote_address));
 449
 450         return tcptls_session;
 451
 452 error:
 453         close(desc->accept_fd);
 454         desc->accept_fd = -1;
 455         if (tcptls_session)
 456                 ao2_ref(tcptls_session, -1);
 457         return NULL;
 458 }
 459
 460 void ast_tcptls_server_start(struct ast_tcptls_session_args *desc)
 461 {
 462         int flags;
 463         int x = 1;
 464
 465         /* Do nothing if nothing has changed */
 466         if (!memcmp(&desc->old_address, &desc->local_address, sizeof(desc->old_address))) {
 467                 ast_debug(1, "Nothing changed in %s\n", desc->name);
 468                 return;
 469         }
 470
 471         desc->old_address = desc->local_address;
 472
 473         /* Shutdown a running server if there is one */
 474         if (desc->master != AST_PTHREADT_NULL) {
 475                 pthread_cancel(desc->master);
 476                 pthread_kill(desc->master, SIGURG);
 477                 pthread_join(desc->master, NULL);
 478         }
 479
 480         if (desc->accept_fd != -1)
 481                 close(desc->accept_fd);
 482
 483         /* If there's no new server, stop here */
 484         if (desc->local_address.sin_family == 0) {
 485                 ast_debug(2, "Server disabled:  %s\n", desc->name);
 486                 return;
 487         }
 488
 489         desc->accept_fd = socket(AF_INET, SOCK_STREAM, 0);
 490         if (desc->accept_fd < 0) {
 491                 ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n", desc->name, strerror(errno));
 492                 return;
 493         }
 494
 495         setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
 496         if (bind(desc->accept_fd, (struct sockaddr *) &desc->local_address, sizeof(desc->local_address))) {
 497                 ast_log(LOG_ERROR, "Unable to bind %s to %s:%d: %s\n",
 498                         desc->name,
 499                         ast_inet_ntoa(desc->local_address.sin_addr), ntohs(desc->local_address.sin_port),
 500                         strerror(errno));
 501                 goto error;
 502         }
 503         if (listen(desc->accept_fd, 10)) {
 504                 ast_log(LOG_ERROR, "Unable to listen for %s!\n", desc->name);
 505                 goto error;
 506         }
 507         flags = fcntl(desc->accept_fd, F_GETFL);
 508         fcntl(desc->accept_fd, F_SETFL, flags | O_NONBLOCK);
 509         if (ast_pthread_create_background(&desc->master, NULL, desc->accept_fn, desc)) {
 510                 ast_log(LOG_ERROR, "Unable to launch thread for %s on %s:%d: %s\n",
 511                         desc->name,
 512                         ast_inet_ntoa(desc->local_address.sin_addr), ntohs(desc->local_address.sin_port),
 513                         strerror(errno));
 514                 goto error;
 515         }
 516         return;
 517
 518 error:
 519         close(desc->accept_fd);
 520         desc->accept_fd = -1;
 521 }
 522
 523 void ast_tcptls_server_stop(struct ast_tcptls_session_args *desc)
 524 {
 525         if (desc->master != AST_PTHREADT_NULL) {
 526                 pthread_cancel(desc->master);
 527                 pthread_kill(desc->master, SIGURG);
 528                 pthread_join(desc->master, NULL);
 529         }
 530         if (desc->accept_fd != -1)
 531                 close(desc->accept_fd);
 532         desc->accept_fd = -1;
 533         ast_debug(2, "Stopped server :: %s\n", desc->name);
 534 }
 535
 536 int ast_tls_read_conf(struct ast_tls_config *tls_cfg, struct ast_tcptls_session_args *tls_desc, const char *varname, const char *value)
 537 {
 538         if (!strcasecmp(varname, "tlsenable") || !strcasecmp(varname, "sslenable")) {
 539                 tls_cfg->enabled = ast_true(value) ? 1 : 0;
 540                 tls_desc->local_address.sin_family = AF_INET;
 541         } else if (!strcasecmp(varname, "tlscertfile") || !strcasecmp(varname, "sslcert") || !strcasecmp(varname, "tlscert")) {
 542                 ast_free(tls_cfg->certfile);
 543                 tls_cfg->certfile = ast_strdup(value);
 544         } else if (!strcasecmp(varname, "tlsprivatekey") || !strcasecmp(varname, "sslprivatekey")) {
 545                 ast_free(tls_cfg->pvtfile);
 546                 tls_cfg->pvtfile = ast_strdup(value);
 547         } else if (!strcasecmp(varname, "tlscipher") || !strcasecmp(varname, "sslcipher")) {
 548                 ast_free(tls_cfg->cipher);
 549                 tls_cfg->cipher = ast_strdup(value);
 550         } else if (!strcasecmp(varname, "tlscafile")) {
 551                 ast_free(tls_cfg->cafile);
 552                 tls_cfg->cafile = ast_strdup(value);
 553         } else if (!strcasecmp(varname, "tlscapath")) {
 554                 ast_free(tls_cfg->capath);
 555                 tls_cfg->capath = ast_strdup(value);
 556         } else if (!strcasecmp(varname, "tlsverifyclient")) {
 557                 ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_VERIFY_CLIENT);
 558         } else if (!strcasecmp(varname, "tlsdontverifyserver")) {
 559                 ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DONT_VERIFY_SERVER);
 560         } else if (!strcasecmp(varname, "tlsbindaddr") || !strcasecmp(varname, "sslbindaddr")) {
 561                 if (ast_parse_arg(value, PARSE_INADDR, &tls_desc->local_address))
 562                         ast_log(LOG_WARNING, "Invalid %s '%s'\n", varname, value);
 563         } else if (!strcasecmp(varname, "tlsbindport") || !strcasecmp(varname, "sslbindport")) {
 564                 tls_desc->local_address.sin_port = htons(atoi(value));
 565         } else if (!strcasecmp(varname, "tlsclientmethod") || !strcasecmp(varname, "sslclientmethod")) {
 566                 if (!strcasecmp(value, "tlsv1")) {
 567                         ast_set_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
 568                         ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
 569                         ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
 570                 } else if (!strcasecmp(value, "sslv3")) {
 571                         ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
 572                         ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
 573                         ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
 574                 } else if (!strcasecmp(value, "sslv2")) {
 575                         ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
 576                         ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
 577                         ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
 578                 }
 579         } else {
 580                 return -1;
 581         }
 582
 583         return 0;
 584 }