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 tcptls_session->f = fdopen(tcptls_session->fd, "w+");
143 setvbuf(tcptls_session->f, NULL, _IONBF, 0);
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));
151 #if defined(HAVE_FUNOPEN) /* the BSD interface */
152 tcptls_session->f = funopen(tcptls_session->ssl, ssl_read, ssl_write, NULL, ssl_close);
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
158 tcptls_session->f = fopencookie(tcptls_session->ssl, "w+", cookie_funcs);
160 /* could add other methods here */
161 ast_debug(2, "no tcptls_session->f methods attempted!");
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))) {
167 peer = SSL_get_peer_certificate(tcptls_session->ssl);
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)) {
176 X509_NAME *name = X509_get_subject_name(peer);
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);
186 str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
187 ASN1_STRING_to_UTF8(&str2, str);
189 if (!strcasecmp(tcptls_session->parent->hostname, (char *) str2))
191 ast_debug(3, "SSL Common Name compare s1='%s' s2='%s'\n", tcptls_session->parent->hostname, str2);
198 ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
201 close(tcptls_session->fd);
202 fclose(tcptls_session->f);
203 ao2_ref(tcptls_session, -1);
211 if (!tcptls_session->f) /* no success opening descriptor stacking */
212 SSL_free(tcptls_session->ssl);
216 if (!tcptls_session->f) {
217 close(tcptls_session->fd);
218 ast_log(LOG_WARNING, "FILE * open failed!\n");
220 if (tcptls_session->parent->tls_cfg) {
221 ast_log(LOG_WARNING, "Attempted a TLS connection without OpenSSL support. This will not work!\n");
224 ao2_ref(tcptls_session, -1);
228 if (tcptls_session && tcptls_session->parent->worker_fn)
229 return tcptls_session->parent->worker_fn(tcptls_session);
231 return tcptls_session;
234 void *ast_tcptls_server_root(void *data)
236 struct ast_tcptls_session_args *desc = data;
238 struct sockaddr_in sin;
240 struct ast_tcptls_session_instance *tcptls_session;
246 if (desc->periodic_fn)
247 desc->periodic_fn(desc);
248 i = ast_wait_for_input(desc->accept_fd, desc->poll_timeout);
251 sinlen = sizeof(sin);
252 fd = accept(desc->accept_fd, (struct sockaddr *) &sin, &sinlen);
254 if ((errno != EAGAIN) && (errno != EINTR))
255 ast_log(LOG_WARNING, "Accept failed: %s\n", strerror(errno));
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));
265 ast_mutex_init(&tcptls_session->lock);
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));
273 tcptls_session->client = 0;
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);
285 static int __ssl_setup(struct ast_tls_config *cfg, int client)
294 SSL_load_error_strings();
295 SSLeay_add_ssl_algorithms();
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());
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());
312 /* SSLv23_server_method() supports TLSv1, SSLv2, and SSLv3 inbound connections. */
313 cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());
317 ast_debug(1, "Sorry, SSL_CTX_new call returned null...\n");
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) {
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);
332 if ((SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, tmpprivate, SSL_FILETYPE_PEM) == 0) || (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0 )) {
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);
342 if (!ast_strlen_zero(cfg->cipher)) {
343 if (SSL_CTX_set_cipher_list(cfg->ssl_ctx, cfg->cipher) == 0 ) {
345 ast_verb(0, "SSL cipher error <%s>", cfg->cipher);
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);
357 ast_verb(0, "SSL certificate ok\n");
362 int ast_ssl_setup(struct ast_tls_config *cfg)
364 return __ssl_setup(cfg, 0);
367 struct ast_tcptls_session_instance *ast_tcptls_client_start(struct ast_tcptls_session_instance *tcptls_session)
369 struct ast_tcptls_session_args *desc;
372 if (!(desc = tcptls_session->parent)) {
373 goto client_start_error;
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",
379 ast_inet_ntoa(desc->remote_address.sin_addr), ntohs(desc->remote_address.sin_port),
381 goto client_start_error;
384 flags = fcntl(desc->accept_fd, F_GETFL);
385 fcntl(desc->accept_fd, F_SETFL, flags & ~O_NONBLOCK);
388 desc->tls_cfg->enabled = 1;
389 __ssl_setup(desc->tls_cfg, 1);
392 return handle_tcptls_connection(tcptls_session);
395 close(desc->accept_fd);
396 desc->accept_fd = -1;
397 if (tcptls_session) {
398 ao2_ref(tcptls_session, -1);
404 struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_session_args *desc)
407 struct ast_tcptls_session_instance *tcptls_session = NULL;
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);
415 desc->old_address = desc->remote_address;
417 if (desc->accept_fd != -1)
418 close(desc->accept_fd);
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));
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",
434 ast_inet_ntoa(desc->local_address.sin_addr), ntohs(desc->local_address.sin_port),
440 if (!(tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor)))
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));
450 return tcptls_session;
453 close(desc->accept_fd);
454 desc->accept_fd = -1;
456 ao2_ref(tcptls_session, -1);
460 void ast_tcptls_server_start(struct ast_tcptls_session_args *desc)
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);
471 desc->old_address = desc->local_address;
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);
480 if (desc->accept_fd != -1)
481 close(desc->accept_fd);
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);
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));
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",
499 ast_inet_ntoa(desc->local_address.sin_addr), ntohs(desc->local_address.sin_port),
503 if (listen(desc->accept_fd, 10)) {
504 ast_log(LOG_ERROR, "Unable to listen for %s!\n", desc->name);
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",
512 ast_inet_ntoa(desc->local_address.sin_addr), ntohs(desc->local_address.sin_port),
519 close(desc->accept_fd);
520 desc->accept_fd = -1;
523 void ast_tcptls_server_stop(struct ast_tcptls_session_args *desc)
525 if (desc->master != AST_PTHREADT_NULL) {
526 pthread_cancel(desc->master);
527 pthread_kill(desc->master, SIGURG);
528 pthread_join(desc->master, NULL);
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);
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)
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);