2 * Asterisk -- An open source telephony toolkit.
4 * Copyright (C) 2007 - 2008, Digium, Inc.
6 * Luigi Rizzo (TCP and TLS server code)
7 * Brett Bryant <brettbryant@gmail.com> (updated for client support)
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.
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.
22 * \brief Code to support TCP and TLS server/client
25 * \author Brett Bryant <brettbryant@gmail.com>
30 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
37 #include <sys/signal.h>
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"
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.
55 static HOOK_T ssl_read(void *cookie, char *buf, LEN_T len)
57 int i = SSL_read(cookie, buf, len-1);
61 ast_verb(0, "ssl read size %d returns %d <%s>\n", (int)len, i, buf);
66 static HOOK_T ssl_write(void *cookie, const char *buf, LEN_T len)
69 char *s = alloca(len+1);
72 ast_verb(0, "ssl write size %d <%s>\n", (int)len, s);
74 return SSL_write(cookie, buf, len);
77 static int ssl_close(void *cookie)
79 close(SSL_get_fd(cookie));
86 HOOK_T ast_tcptls_server_read(struct ast_tcptls_session_instance *tcptls_session, void *buf, size_t count)
88 if (tcptls_session->fd == -1) {
89 ast_log(LOG_ERROR, "server_read called with an fd of -1\n");
95 if (tcptls_session->ssl)
96 return ssl_read(tcptls_session->ssl, buf, count);
98 return read(tcptls_session->fd, buf, count);
101 HOOK_T ast_tcptls_server_write(struct ast_tcptls_session_instance *tcptls_session, const void *buf, size_t count)
103 if (tcptls_session->fd == -1) {
104 ast_log(LOG_ERROR, "server_write called with an fd of -1\n");
110 if (tcptls_session->ssl)
111 return ssl_write(tcptls_session->ssl, buf, count);
113 return write(tcptls_session->fd, buf, count);
116 static void session_instance_destructor(void *obj)
118 struct ast_tcptls_session_instance *i = obj;
119 ast_mutex_destroy(&i->lock);
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.
127 * \note must decrement ref count before returning NULL on error
129 static void *handle_tcptls_connection(void *data)
131 struct ast_tcptls_session_instance *tcptls_session = data;
133 int (*ssl_setup)(SSL *) = (tcptls_session->client) ? SSL_connect : SSL_accept;
139 * open a FILE * as appropriate.
141 if (!tcptls_session->parent->tls_cfg) {
142 if ((tcptls_session->f = fdopen(tcptls_session->fd, "w+"))) {
143 if(setvbuf(tcptls_session->f, NULL, _IONBF, 0)) {
144 fclose(tcptls_session->f);
145 tcptls_session->f = NULL;
150 else if ( (tcptls_session->ssl = SSL_new(tcptls_session->parent->tls_cfg->ssl_ctx)) ) {
151 SSL_set_fd(tcptls_session->ssl, tcptls_session->fd);
152 if ((ret = ssl_setup(tcptls_session->ssl)) <= 0) {
153 ast_verb(2, "Problem setting up ssl connection: %s\n", ERR_error_string(ERR_get_error(), err));
155 #if defined(HAVE_FUNOPEN) /* the BSD interface */
156 tcptls_session->f = funopen(tcptls_session->ssl, ssl_read, ssl_write, NULL, ssl_close);
158 #elif defined(HAVE_FOPENCOOKIE) /* the glibc/linux interface */
159 static const cookie_io_functions_t cookie_funcs = {
160 ssl_read, ssl_write, NULL, ssl_close
162 tcptls_session->f = fopencookie(tcptls_session->ssl, "w+", cookie_funcs);
164 /* could add other methods here */
165 ast_debug(2, "no tcptls_session->f methods attempted!");
167 if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
168 || (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
171 peer = SSL_get_peer_certificate(tcptls_session->ssl);
173 ast_log(LOG_WARNING, "No peer SSL certificate\n");
174 res = SSL_get_verify_result(tcptls_session->ssl);
175 if (res != X509_V_OK)
176 ast_log(LOG_ERROR, "Certificate did not verify: %s\n", X509_verify_cert_error_string(res));
177 if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
180 X509_NAME *name = X509_get_subject_name(peer);
185 /* Walk the certificate to check all available "Common Name" */
186 /* XXX Probably should do a gethostbyname on the hostname and compare that as well */
187 pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
190 str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
191 ASN1_STRING_to_UTF8(&str2, str);
193 if (!strcasecmp(tcptls_session->parent->hostname, (char *) str2))
195 ast_debug(3, "SSL Common Name compare s1='%s' s2='%s'\n", tcptls_session->parent->hostname, str2);
202 ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
205 close(tcptls_session->fd);
206 fclose(tcptls_session->f);
207 ao2_ref(tcptls_session, -1);
215 if (!tcptls_session->f) /* no success opening descriptor stacking */
216 SSL_free(tcptls_session->ssl);
220 if (!tcptls_session->f) {
221 close(tcptls_session->fd);
222 ast_log(LOG_WARNING, "FILE * open failed!\n");
224 if (tcptls_session->parent->tls_cfg) {
225 ast_log(LOG_WARNING, "Attempted a TLS connection without OpenSSL support. This will not work!\n");
228 ao2_ref(tcptls_session, -1);
232 if (tcptls_session && tcptls_session->parent->worker_fn)
233 return tcptls_session->parent->worker_fn(tcptls_session);
235 return tcptls_session;
238 void *ast_tcptls_server_root(void *data)
240 struct ast_tcptls_session_args *desc = data;
242 struct ast_sockaddr addr;
243 struct ast_tcptls_session_instance *tcptls_session;
249 if (desc->periodic_fn)
250 desc->periodic_fn(desc);
251 i = ast_wait_for_input(desc->accept_fd, desc->poll_timeout);
254 fd = ast_accept(desc->accept_fd, &addr);
256 if ((errno != EAGAIN) && (errno != EINTR))
257 ast_log(LOG_WARNING, "Accept failed: %s\n", strerror(errno));
260 tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor);
261 if (!tcptls_session) {
262 ast_log(LOG_WARNING, "No memory for new session: %s\n", strerror(errno));
267 ast_mutex_init(&tcptls_session->lock);
269 flags = fcntl(fd, F_GETFL);
270 fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
271 tcptls_session->fd = fd;
272 tcptls_session->parent = desc;
273 ast_sockaddr_copy(&tcptls_session->remote_address, &addr);
275 tcptls_session->client = 0;
277 /* This thread is now the only place that controls the single ref to tcptls_session */
278 if (ast_pthread_create_detached_background(&launched, NULL, handle_tcptls_connection, tcptls_session)) {
279 ast_log(LOG_WARNING, "Unable to launch helper thread: %s\n", strerror(errno));
280 close(tcptls_session->fd);
281 ao2_ref(tcptls_session, -1);
287 static int __ssl_setup(struct ast_tls_config *cfg, int client)
296 SSL_load_error_strings();
297 SSLeay_add_ssl_algorithms();
300 #ifndef OPENSSL_NO_SSL2
301 if (ast_test_flag(&cfg->flags, AST_SSL_SSLV2_CLIENT)) {
302 cfg->ssl_ctx = SSL_CTX_new(SSLv2_client_method());
305 if (ast_test_flag(&cfg->flags, AST_SSL_SSLV3_CLIENT)) {
306 cfg->ssl_ctx = SSL_CTX_new(SSLv3_client_method());
307 } else if (ast_test_flag(&cfg->flags, AST_SSL_TLSV1_CLIENT)) {
308 cfg->ssl_ctx = SSL_CTX_new(TLSv1_client_method());
310 /* SSLv23_client_method() sends SSLv2, this was the original
311 * default for ssl clients before the option was given to
312 * pick what protocol a client should use. In order not
313 * to break expected behavior it remains the default. */
314 cfg->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
317 /* SSLv23_server_method() supports TLSv1, SSLv2, and SSLv3 inbound connections. */
318 cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());
322 ast_debug(1, "Sorry, SSL_CTX_new call returned null...\n");
326 if (!ast_strlen_zero(cfg->certfile)) {
327 char *tmpprivate = ast_strlen_zero(cfg->pvtfile) ? cfg->certfile : cfg->pvtfile;
328 if (SSL_CTX_use_certificate_file(cfg->ssl_ctx, cfg->certfile, SSL_FILETYPE_PEM) == 0) {
330 /* Clients don't need a certificate, but if its setup we can use it */
331 ast_verb(0, "SSL error loading cert file. <%s>", cfg->certfile);
337 if ((SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, tmpprivate, SSL_FILETYPE_PEM) == 0) || (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0 )) {
339 /* Clients don't need a private key, but if its setup we can use it */
340 ast_verb(0, "SSL error loading private key file. <%s>", tmpprivate);
347 if (!ast_strlen_zero(cfg->cipher)) {
348 if (SSL_CTX_set_cipher_list(cfg->ssl_ctx, cfg->cipher) == 0 ) {
350 ast_verb(0, "SSL cipher error <%s>", cfg->cipher);
357 if (!ast_strlen_zero(cfg->cafile) || !ast_strlen_zero(cfg->capath)) {
358 if (SSL_CTX_load_verify_locations(cfg->ssl_ctx, S_OR(cfg->cafile, NULL), S_OR(cfg->capath,NULL)) == 0)
359 ast_verb(0, "SSL CA file(%s)/path(%s) error\n", cfg->cafile, cfg->capath);
362 ast_verb(0, "SSL certificate ok\n");
367 int ast_ssl_setup(struct ast_tls_config *cfg)
369 return __ssl_setup(cfg, 0);
372 struct ast_tcptls_session_instance *ast_tcptls_client_start(struct ast_tcptls_session_instance *tcptls_session)
374 struct ast_tcptls_session_args *desc;
377 if (!(desc = tcptls_session->parent)) {
378 goto client_start_error;
381 if (ast_connect(desc->accept_fd, &desc->remote_address)) {
382 ast_log(LOG_ERROR, "Unable to connect %s to %s: %s\n",
384 ast_sockaddr_stringify(&desc->remote_address),
386 goto client_start_error;
389 flags = fcntl(desc->accept_fd, F_GETFL);
390 fcntl(desc->accept_fd, F_SETFL, flags & ~O_NONBLOCK);
393 desc->tls_cfg->enabled = 1;
394 __ssl_setup(desc->tls_cfg, 1);
397 return handle_tcptls_connection(tcptls_session);
400 close(desc->accept_fd);
401 desc->accept_fd = -1;
402 if (tcptls_session) {
403 ao2_ref(tcptls_session, -1);
409 struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_session_args *desc)
412 struct ast_tcptls_session_instance *tcptls_session = NULL;
414 /* Do nothing if nothing has changed */
415 if (!ast_sockaddr_cmp(&desc->old_address, &desc->remote_address)) {
416 ast_debug(1, "Nothing changed in %s\n", desc->name);
420 /* If we return early, there is no connection */
421 ast_sockaddr_setnull(&desc->old_address);
423 if (desc->accept_fd != -1)
424 close(desc->accept_fd);
426 desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->remote_address) ?
427 AF_INET6 : AF_INET, SOCK_STREAM, IPPROTO_TCP);
428 if (desc->accept_fd < 0) {
429 ast_log(LOG_WARNING, "Unable to allocate socket for %s: %s\n",
430 desc->name, strerror(errno));
434 /* if a local address was specified, bind to it so the connection will
435 originate from the desired address */
436 if (!ast_sockaddr_isnull(&desc->local_address)) {
437 setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
438 if (ast_bind(desc->accept_fd, &desc->local_address)) {
439 ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
441 ast_sockaddr_stringify(&desc->local_address),
447 if (!(tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor)))
450 ast_mutex_init(&tcptls_session->lock);
451 tcptls_session->client = 1;
452 tcptls_session->fd = desc->accept_fd;
453 tcptls_session->parent = desc;
454 tcptls_session->parent->worker_fn = NULL;
455 ast_sockaddr_copy(&tcptls_session->remote_address,
456 &desc->remote_address);
458 /* Set current info */
459 ast_sockaddr_copy(&desc->old_address, &desc->remote_address);
460 return tcptls_session;
463 close(desc->accept_fd);
464 desc->accept_fd = -1;
466 ao2_ref(tcptls_session, -1);
470 void ast_tcptls_server_start(struct ast_tcptls_session_args *desc)
475 /* Do nothing if nothing has changed */
476 if (!ast_sockaddr_cmp(&desc->old_address, &desc->local_address)) {
477 ast_debug(1, "Nothing changed in %s\n", desc->name);
481 /* If we return early, there is no one listening */
482 ast_sockaddr_setnull(&desc->old_address);
484 /* Shutdown a running server if there is one */
485 if (desc->master != AST_PTHREADT_NULL) {
486 pthread_cancel(desc->master);
487 pthread_kill(desc->master, SIGURG);
488 pthread_join(desc->master, NULL);
491 if (desc->accept_fd != -1)
492 close(desc->accept_fd);
494 /* If there's no new server, stop here */
495 if (ast_sockaddr_isnull(&desc->local_address)) {
496 ast_debug(2, "Server disabled: %s\n", desc->name);
500 desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->local_address) ?
501 AF_INET6 : AF_INET, SOCK_STREAM, 0);
502 if (desc->accept_fd < 0) {
503 ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n", desc->name, strerror(errno));
507 setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
508 if (ast_bind(desc->accept_fd, &desc->local_address)) {
509 ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
511 ast_sockaddr_stringify(&desc->local_address),
515 if (listen(desc->accept_fd, 10)) {
516 ast_log(LOG_ERROR, "Unable to listen for %s!\n", desc->name);
519 flags = fcntl(desc->accept_fd, F_GETFL);
520 fcntl(desc->accept_fd, F_SETFL, flags | O_NONBLOCK);
521 if (ast_pthread_create_background(&desc->master, NULL, desc->accept_fn, desc)) {
522 ast_log(LOG_ERROR, "Unable to launch thread for %s on %s: %s\n",
524 ast_sockaddr_stringify(&desc->local_address),
529 /* Set current info */
530 ast_sockaddr_copy(&desc->old_address, &desc->local_address);
535 close(desc->accept_fd);
536 desc->accept_fd = -1;
539 void ast_tcptls_server_stop(struct ast_tcptls_session_args *desc)
541 if (desc->master != AST_PTHREADT_NULL) {
542 pthread_cancel(desc->master);
543 pthread_kill(desc->master, SIGURG);
544 pthread_join(desc->master, NULL);
545 desc->master = AST_PTHREADT_NULL;
547 if (desc->accept_fd != -1)
548 close(desc->accept_fd);
549 desc->accept_fd = -1;
550 ast_debug(2, "Stopped server :: %s\n", desc->name);
553 int ast_tls_read_conf(struct ast_tls_config *tls_cfg, struct ast_tcptls_session_args *tls_desc, const char *varname, const char *value)
555 if (!strcasecmp(varname, "tlsenable") || !strcasecmp(varname, "sslenable")) {
556 tls_cfg->enabled = ast_true(value) ? 1 : 0;
557 } else if (!strcasecmp(varname, "tlscertfile") || !strcasecmp(varname, "sslcert") || !strcasecmp(varname, "tlscert")) {
558 ast_free(tls_cfg->certfile);
559 tls_cfg->certfile = ast_strdup(value);
560 } else if (!strcasecmp(varname, "tlsprivatekey") || !strcasecmp(varname, "sslprivatekey")) {
561 ast_free(tls_cfg->pvtfile);
562 tls_cfg->pvtfile = ast_strdup(value);
563 } else if (!strcasecmp(varname, "tlscipher") || !strcasecmp(varname, "sslcipher")) {
564 ast_free(tls_cfg->cipher);
565 tls_cfg->cipher = ast_strdup(value);
566 } else if (!strcasecmp(varname, "tlscafile")) {
567 ast_free(tls_cfg->cafile);
568 tls_cfg->cafile = ast_strdup(value);
569 } else if (!strcasecmp(varname, "tlscapath") || !strcasecmp(varname, "tlscadir")) {
570 ast_free(tls_cfg->capath);
571 tls_cfg->capath = ast_strdup(value);
572 } else if (!strcasecmp(varname, "tlsverifyclient")) {
573 ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_VERIFY_CLIENT);
574 } else if (!strcasecmp(varname, "tlsdontverifyserver")) {
575 ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DONT_VERIFY_SERVER);
576 } else if (!strcasecmp(varname, "tlsbindaddr") || !strcasecmp(varname, "sslbindaddr")) {
577 if (ast_parse_arg(value, PARSE_ADDR, &tls_desc->local_address))
578 ast_log(LOG_WARNING, "Invalid %s '%s'\n", varname, value);
579 } else if (!strcasecmp(varname, "tlsclientmethod") || !strcasecmp(varname, "sslclientmethod")) {
580 if (!strcasecmp(value, "tlsv1")) {
581 ast_set_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
582 ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
583 ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
584 } else if (!strcasecmp(value, "sslv3")) {
585 ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
586 ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
587 ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
588 } else if (!strcasecmp(value, "sslv2")) {
589 ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
590 ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
591 ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);