1 /*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25 #include "private-lib-core.h"
26 #include "private-lib-tls-openssl.h"
27
28 int openssl_websocket_private_data_index,
29 openssl_SSL_CTX_private_data_index;
30
31 /*
32 * Care: many openssl apis return 1 for success. These are translated to the
33 * lws convention of 0 for success.
34 */
35
lws_openssl_describe_cipher(struct lws * wsi)36 int lws_openssl_describe_cipher(struct lws *wsi)
37 {
38 #if !defined(LWS_WITH_NO_LOGS) && !defined(USE_WOLFSSL)
39 int np = -1;
40 SSL *s = wsi->tls.ssl;
41
42 SSL_get_cipher_bits(s, &np);
43 lwsl_info("%s: %s: %s, %s, %d bits, %s\n", __func__, lws_wsi_tag(wsi),
44 SSL_get_cipher_name(s), SSL_get_cipher(s), np,
45 SSL_get_cipher_version(s));
46 #endif
47
48 return 0;
49 }
50
lws_ssl_get_error(struct lws * wsi,int n)51 int lws_ssl_get_error(struct lws *wsi, int n)
52 {
53 int m;
54
55 if (!wsi->tls.ssl)
56 return 99;
57
58 m = SSL_get_error(wsi->tls.ssl, n);
59 lwsl_debug("%s: %p %d -> %d (errno %d)\n", __func__, wsi->tls.ssl, n, m, LWS_ERRNO);
60
61 // assert (LWS_ERRNO != 9);
62
63 return m;
64 }
65
66 #if defined(LWS_WITH_SERVER)
67 static int
lws_context_init_ssl_pem_passwd_cb(char * buf,int size,int rwflag,void * userdata)68 lws_context_init_ssl_pem_passwd_cb(char *buf, int size, int rwflag,
69 void *userdata)
70 {
71 struct lws_context_creation_info * info =
72 (struct lws_context_creation_info *)userdata;
73
74 strncpy(buf, info->ssl_private_key_password, (unsigned int)size);
75 buf[size - 1] = '\0';
76
77 return (int)strlen(buf);
78 }
79 #endif
80
81 #if defined(LWS_WITH_CLIENT)
82 static int
lws_context_init_ssl_pem_passwd_client_cb(char * buf,int size,int rwflag,void * userdata)83 lws_context_init_ssl_pem_passwd_client_cb(char *buf, int size, int rwflag,
84 void *userdata)
85 {
86 struct lws_context_creation_info * info =
87 (struct lws_context_creation_info *)userdata;
88 const char *p = info->ssl_private_key_password;
89
90 if (info->client_ssl_private_key_password)
91 p = info->client_ssl_private_key_password;
92
93 strncpy(buf, p, (unsigned int)size);
94 buf[size - 1] = '\0';
95
96 return (int)strlen(buf);
97 }
98 #endif
99
100 void
lws_ssl_bind_passphrase(SSL_CTX * ssl_ctx,int is_client,const struct lws_context_creation_info * info)101 lws_ssl_bind_passphrase(SSL_CTX *ssl_ctx, int is_client,
102 const struct lws_context_creation_info *info)
103 {
104 if (
105 #if defined(LWS_WITH_SERVER)
106 !info->ssl_private_key_password
107 #endif
108 #if defined(LWS_WITH_SERVER) && defined(LWS_WITH_CLIENT)
109 &&
110 #endif
111 #if defined(LWS_WITH_CLIENT)
112 !info->client_ssl_private_key_password
113 #endif
114 )
115 return;
116 /*
117 * password provided, set ssl callback and user data
118 * for checking password which will be trigered during
119 * SSL_CTX_use_PrivateKey_file function
120 */
121 SSL_CTX_set_default_passwd_cb_userdata(ssl_ctx, (void *)info);
122 SSL_CTX_set_default_passwd_cb(ssl_ctx, is_client ?
123 #if defined(LWS_WITH_CLIENT)
124 lws_context_init_ssl_pem_passwd_client_cb:
125 #else
126 NULL:
127 #endif
128 #if defined(LWS_WITH_SERVER)
129 lws_context_init_ssl_pem_passwd_cb
130 #else
131 NULL
132 #endif
133 );
134 }
135
136 #if defined(LWS_WITH_CLIENT)
137 static void
lws_ssl_destroy_client_ctx(struct lws_vhost * vhost)138 lws_ssl_destroy_client_ctx(struct lws_vhost *vhost)
139 {
140 if (vhost->tls.user_supplied_ssl_ctx || !vhost->tls.ssl_client_ctx)
141 return;
142
143 if (vhost->tls.tcr && --vhost->tls.tcr->refcount)
144 return;
145
146 SSL_CTX_free(vhost->tls.ssl_client_ctx);
147 vhost->tls.ssl_client_ctx = NULL;
148
149 vhost->context->tls.count_client_contexts--;
150
151 if (vhost->tls.tcr) {
152 lws_dll2_remove(&vhost->tls.tcr->cc_list);
153 lws_free(vhost->tls.tcr);
154 vhost->tls.tcr = NULL;
155 }
156 }
157 #endif
158 void
lws_ssl_destroy(struct lws_vhost * vhost)159 lws_ssl_destroy(struct lws_vhost *vhost)
160 {
161 if (!lws_check_opt(vhost->context->options,
162 LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT))
163 return;
164
165 if (vhost->tls.ssl_ctx)
166 SSL_CTX_free(vhost->tls.ssl_ctx);
167 #if defined(LWS_WITH_CLIENT)
168 lws_ssl_destroy_client_ctx(vhost);
169 #endif
170
171 // after 1.1.0 no need
172 #if (OPENSSL_VERSION_NUMBER < 0x10100000)
173 // <= 1.0.1f = old api, 1.0.1g+ = new api
174 #if (OPENSSL_VERSION_NUMBER <= 0x1000106f) || defined(USE_WOLFSSL)
175 ERR_remove_state(0);
176 #else
177 #if OPENSSL_VERSION_NUMBER >= 0x1010005f && \
178 !defined(LIBRESSL_VERSION_NUMBER) && \
179 !defined(OPENSSL_IS_BORINGSSL)
180 ERR_remove_thread_state();
181 #else
182 ERR_remove_thread_state(NULL);
183 #endif
184 #endif
185 /* not needed after 1.1.0 */
186 #if (OPENSSL_VERSION_NUMBER >= 0x10002000) && \
187 (OPENSSL_VERSION_NUMBER <= 0x10100000)
188 SSL_COMP_free_compression_methods();
189 #endif
190 ERR_free_strings();
191 EVP_cleanup();
192 CRYPTO_cleanup_all_ex_data();
193 #endif
194 }
195
196 int
lws_ssl_capable_read(struct lws * wsi,unsigned char * buf,size_t len)197 lws_ssl_capable_read(struct lws *wsi, unsigned char *buf, size_t len)
198 {
199 struct lws_context *context = wsi->a.context;
200 struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
201 int n = 0, m;
202
203 if (!wsi->tls.ssl)
204 return lws_ssl_capable_read_no_ssl(wsi, buf, len);
205
206 #ifndef WIN32
207 errno = 0;
208 #else
209 WSASetLastError(0);
210 #endif
211 ERR_clear_error();
212 n = SSL_read(wsi->tls.ssl, buf, (int)(ssize_t)len);
213 #if defined(LWS_PLAT_FREERTOS)
214 if (!n && errno == LWS_ENOTCONN) {
215 lwsl_debug("%s: SSL_read ENOTCONN\n", lws_wsi_tag(wsi));
216 return LWS_SSL_CAPABLE_ERROR;
217 }
218 #endif
219
220 lwsl_debug("%s: SSL_read says %d\n", lws_wsi_tag(wsi), n);
221 /* manpage: returning 0 means connection shut down
222 *
223 * 2018-09-10: https://github.com/openssl/openssl/issues/1903
224 *
225 * So, in summary, if you get a 0 or -1 return from SSL_read() /
226 * SSL_write(), you should call SSL_get_error():
227 *
228 * - If you get back SSL_ERROR_RETURN_ZERO then you know the connection
229 * has been cleanly shutdown by the peer. To fully close the
230 * connection you may choose to call SSL_shutdown() to send a
231 * close_notify back.
232 *
233 * - If you get back SSL_ERROR_SSL then some kind of internal or
234 * protocol error has occurred. More details will be on the SSL error
235 * queue. You can also call SSL_get_shutdown(). If this indicates a
236 * state of SSL_RECEIVED_SHUTDOWN then you know a fatal alert has
237 * been received from the peer (if it had been a close_notify then
238 * SSL_get_error() would have returned SSL_ERROR_RETURN_ZERO).
239 * SSL_ERROR_SSL is considered fatal - you should not call
240 * SSL_shutdown() in this case.
241 *
242 * - If you get back SSL_ERROR_SYSCALL then some kind of fatal (i.e.
243 * non-retryable) error has occurred in a system call.
244 */
245 if (n <= 0) {
246 m = lws_ssl_get_error(wsi, n);
247 lwsl_debug("%s: ssl err %d errno %d\n", lws_wsi_tag(wsi), m, LWS_ERRNO);
248 if (m == SSL_ERROR_ZERO_RETURN) /* cleanly shut down */
249 goto do_err;
250
251 if (m == SSL_ERROR_SSL)
252 lws_tls_err_describe_clear();
253
254 /* hm not retryable.. could be 0 size pkt or error */
255
256 if (m == SSL_ERROR_SSL || m == SSL_ERROR_SYSCALL ||
257 LWS_ERRNO == LWS_ENOTCONN) {
258
259 /* unclean, eg closed conn */
260
261 wsi->socket_is_permanently_unusable = 1;
262 do_err:
263 #if defined(LWS_WITH_SYS_METRICS)
264 if (wsi->a.vhost)
265 lws_metric_event(wsi->a.vhost->mt_traffic_rx,
266 METRES_NOGO, 0);
267 #endif
268 return LWS_SSL_CAPABLE_ERROR;
269 }
270
271 /* retryable? */
272
273 if (SSL_want_read(wsi->tls.ssl)) {
274 lwsl_debug("%s: WANT_READ\n", __func__);
275 lwsl_debug("%s: LWS_SSL_CAPABLE_MORE_SERVICE\n", lws_wsi_tag(wsi));
276 return LWS_SSL_CAPABLE_MORE_SERVICE;
277 }
278 if (SSL_want_write(wsi->tls.ssl)) {
279 lwsl_info("%s: WANT_WRITE\n", __func__);
280 lwsl_debug("%s: LWS_SSL_CAPABLE_MORE_SERVICE\n", lws_wsi_tag(wsi));
281 wsi->tls_read_wanted_write = 1;
282 lws_callback_on_writable(wsi);
283 return LWS_SSL_CAPABLE_MORE_SERVICE;
284 }
285
286 /* keep on trucking it seems */
287 }
288
289 #if defined(LWS_TLS_LOG_PLAINTEXT_RX)
290 /*
291 * If using openssl type tls library, this is the earliest point for all
292 * paths to dump what was received as decrypted data from the tls tunnel
293 */
294 lwsl_notice("%s: len %d\n", __func__, n);
295 lwsl_hexdump_notice(buf, (unsigned int)n);
296 #endif
297
298 #if defined(LWS_WITH_SYS_METRICS)
299 if (wsi->a.vhost)
300 lws_metric_event(wsi->a.vhost->mt_traffic_rx, METRES_GO, (u_mt_t)n);
301 #endif
302
303 /*
304 * if it was our buffer that limited what we read,
305 * check if SSL has additional data pending inside SSL buffers.
306 *
307 * Because these won't signal at the network layer with POLLIN
308 * and if we don't realize, this data will sit there forever
309 */
310 if (n != (int)(ssize_t)len)
311 goto bail;
312 if (!wsi->tls.ssl)
313 goto bail;
314
315 if (SSL_pending(wsi->tls.ssl)) {
316 if (lws_dll2_is_detached(&wsi->tls.dll_pending_tls))
317 lws_dll2_add_head(&wsi->tls.dll_pending_tls,
318 &pt->tls.dll_pending_tls_owner);
319 } else
320 __lws_ssl_remove_wsi_from_buffered_list(wsi);
321
322 return n;
323 bail:
324 lws_ssl_remove_wsi_from_buffered_list(wsi);
325
326 return n;
327 }
328
329 int
lws_ssl_pending(struct lws * wsi)330 lws_ssl_pending(struct lws *wsi)
331 {
332 if (!wsi->tls.ssl)
333 return 0;
334
335 return SSL_pending(wsi->tls.ssl);
336 }
337
338 int
lws_ssl_capable_write(struct lws * wsi,unsigned char * buf,size_t len)339 lws_ssl_capable_write(struct lws *wsi, unsigned char *buf, size_t len)
340 {
341 int n, m;
342
343
344 #if defined(LWS_TLS_LOG_PLAINTEXT_TX)
345 /*
346 * If using OpenSSL type tls library, this is the last point for all
347 * paths before sending data into the tls tunnel, where you can dump it
348 * and see what is being sent.
349 */
350 lwsl_notice("%s: len %u\n", __func__, (unsigned int)len);
351 lwsl_hexdump_notice(buf, len);
352 #endif
353
354 if (!wsi->tls.ssl)
355 return lws_ssl_capable_write_no_ssl(wsi, buf, len);
356
357 errno = 0;
358 ERR_clear_error();
359 n = SSL_write(wsi->tls.ssl, buf, (int)(ssize_t)len);
360 if (n > 0) {
361 #if defined(LWS_WITH_SYS_METRICS)
362 if (wsi->a.vhost)
363 lws_metric_event(wsi->a.vhost->mt_traffic_tx,
364 METRES_GO, (u_mt_t)n);
365 #endif
366 return n;
367 }
368
369 m = lws_ssl_get_error(wsi, n);
370 if (m != SSL_ERROR_SYSCALL) {
371 if (m == SSL_ERROR_WANT_READ || SSL_want_read(wsi->tls.ssl)) {
372 lwsl_notice("%s: want read\n", __func__);
373
374 return LWS_SSL_CAPABLE_MORE_SERVICE;
375 }
376
377 if (m == SSL_ERROR_WANT_WRITE || SSL_want_write(wsi->tls.ssl)) {
378 lws_set_blocking_send(wsi);
379
380 lwsl_debug("%s: want write\n", __func__);
381
382 return LWS_SSL_CAPABLE_MORE_SERVICE;
383 }
384 }
385
386 lwsl_debug("%s failed: %s\n",__func__, ERR_error_string((unsigned int)m, NULL));
387 lws_tls_err_describe_clear();
388
389 wsi->socket_is_permanently_unusable = 1;
390
391 #if defined(LWS_WITH_SYS_METRICS)
392 if (wsi->a.vhost)
393 lws_metric_event(wsi->a.vhost->mt_traffic_tx,
394 METRES_NOGO, 0);
395 #endif
396
397 return LWS_SSL_CAPABLE_ERROR;
398 }
399
400 void
lws_ssl_info_callback(const SSL * ssl,int where,int ret)401 lws_ssl_info_callback(const SSL *ssl, int where, int ret)
402 {
403 struct lws *wsi;
404 struct lws_context *context;
405 struct lws_ssl_info si;
406 int fd;
407
408 #ifndef USE_WOLFSSL
409 context = (struct lws_context *)SSL_CTX_get_ex_data(
410 SSL_get_SSL_CTX(ssl),
411 openssl_SSL_CTX_private_data_index);
412 #else
413 context = (struct lws_context *)SSL_CTX_get_ex_data(
414 SSL_get_SSL_CTX((SSL*) ssl),
415 openssl_SSL_CTX_private_data_index);
416 #endif
417 if (!context)
418 return;
419
420 fd = SSL_get_fd(ssl);
421 if (fd < 0 || (fd - lws_plat_socket_offset()) < 0)
422 return;
423
424 wsi = wsi_from_fd(context, fd);
425 if (!wsi)
426 return;
427
428 if (!(where & wsi->a.vhost->tls.ssl_info_event_mask))
429 return;
430
431 si.where = where;
432 si.ret = ret;
433
434 if (user_callback_handle_rxflow(wsi->a.protocol->callback,
435 wsi, LWS_CALLBACK_SSL_INFO,
436 wsi->user_space, &si, 0))
437 lws_set_timeout(wsi, PENDING_TIMEOUT_KILLED_BY_SSL_INFO, -1);
438 }
439
440
441 int
lws_ssl_close(struct lws * wsi)442 lws_ssl_close(struct lws *wsi)
443 {
444 lws_sockfd_type n;
445
446 if (!wsi->tls.ssl)
447 return 0; /* not handled */
448
449 #if defined (LWS_HAVE_SSL_SET_INFO_CALLBACK)
450 /* kill ssl callbacks, because we will remove the fd from the
451 * table linking it to the wsi
452 */
453 if (wsi->a.vhost->tls.ssl_info_event_mask)
454 SSL_set_info_callback(wsi->tls.ssl, NULL);
455 #endif
456
457 #if defined(LWS_TLS_SYNTHESIZE_CB)
458 lws_sul_cancel(&wsi->tls.sul_cb_synth);
459 /*
460 * ... check the session in case it did not live long enough to get
461 * the scheduled callback to sample it
462 */
463 lws_sess_cache_synth_cb(&wsi->tls.sul_cb_synth);
464 #endif
465
466 n = SSL_get_fd(wsi->tls.ssl);
467 if (!wsi->socket_is_permanently_unusable)
468 SSL_shutdown(wsi->tls.ssl);
469 compatible_close(n);
470 SSL_free(wsi->tls.ssl);
471 wsi->tls.ssl = NULL;
472
473 lws_tls_restrict_return(wsi);
474
475 // lwsl_notice("%s: ssl restr %d, simul %d\n", __func__,
476 // wsi->a.context->simultaneous_ssl_restriction,
477 // wsi->a.context->simultaneous_ssl);
478
479 return 1; /* handled */
480 }
481
482 void
lws_ssl_SSL_CTX_destroy(struct lws_vhost * vhost)483 lws_ssl_SSL_CTX_destroy(struct lws_vhost *vhost)
484 {
485 if (vhost->tls.ssl_ctx)
486 SSL_CTX_free(vhost->tls.ssl_ctx);
487
488 #if defined(LWS_WITH_CLIENT)
489 lws_ssl_destroy_client_ctx(vhost);
490 #endif
491
492 #if defined(LWS_WITH_ACME)
493 lws_tls_acme_sni_cert_destroy(vhost);
494 #endif
495 }
496
497 void
lws_ssl_context_destroy(struct lws_context * context)498 lws_ssl_context_destroy(struct lws_context *context)
499 {
500 // after 1.1.0 no need
501 #if (OPENSSL_VERSION_NUMBER < 0x10100000)
502 // <= 1.0.1f = old api, 1.0.1g+ = new api
503 #if (OPENSSL_VERSION_NUMBER <= 0x1000106f) || defined(USE_WOLFSSL)
504 ERR_remove_state(0);
505 #else
506 #if OPENSSL_VERSION_NUMBER >= 0x1010005f && \
507 !defined(LIBRESSL_VERSION_NUMBER) && \
508 !defined(OPENSSL_IS_BORINGSSL)
509 ERR_remove_thread_state();
510 #else
511 ERR_remove_thread_state(NULL);
512 #endif
513 #endif
514 // after 1.1.0 no need
515 #if (OPENSSL_VERSION_NUMBER >= 0x10002000) && (OPENSSL_VERSION_NUMBER <= 0x10100000)
516 SSL_COMP_free_compression_methods();
517 #endif
518 ERR_free_strings();
519 EVP_cleanup();
520 CRYPTO_cleanup_all_ex_data();
521 #endif
522 }
523
524 lws_tls_ctx *
lws_tls_ctx_from_wsi(struct lws * wsi)525 lws_tls_ctx_from_wsi(struct lws *wsi)
526 {
527 if (!wsi->tls.ssl)
528 return NULL;
529
530 return SSL_get_SSL_CTX(wsi->tls.ssl);
531 }
532
533 enum lws_ssl_capable_status
__lws_tls_shutdown(struct lws * wsi)534 __lws_tls_shutdown(struct lws *wsi)
535 {
536 int n;
537
538 #ifndef WIN32
539 errno = 0;
540 #else
541 WSASetLastError(0);
542 #endif
543 ERR_clear_error();
544 n = SSL_shutdown(wsi->tls.ssl);
545 lwsl_debug("SSL_shutdown=%d for fd %d\n", n, wsi->desc.sockfd);
546 switch (n) {
547 case 1: /* successful completion */
548 n = shutdown(wsi->desc.sockfd, SHUT_WR);
549 return LWS_SSL_CAPABLE_DONE;
550
551 case 0: /* needs a retry */
552 __lws_change_pollfd(wsi, 0, LWS_POLLIN);
553 return LWS_SSL_CAPABLE_MORE_SERVICE;
554
555 default: /* fatal error, or WANT */
556 n = SSL_get_error(wsi->tls.ssl, n);
557 if (n != SSL_ERROR_SYSCALL && n != SSL_ERROR_SSL) {
558 if (SSL_want_read(wsi->tls.ssl)) {
559 lwsl_debug("(wants read)\n");
560 __lws_change_pollfd(wsi, 0, LWS_POLLIN);
561 return LWS_SSL_CAPABLE_MORE_SERVICE_READ;
562 }
563 if (SSL_want_write(wsi->tls.ssl)) {
564 lwsl_debug("(wants write)\n");
565 __lws_change_pollfd(wsi, 0, LWS_POLLOUT);
566 return LWS_SSL_CAPABLE_MORE_SERVICE_WRITE;
567 }
568 }
569 return LWS_SSL_CAPABLE_ERROR;
570 }
571 }
572
573
574 static int
tops_fake_POLLIN_for_buffered_openssl(struct lws_context_per_thread * pt)575 tops_fake_POLLIN_for_buffered_openssl(struct lws_context_per_thread *pt)
576 {
577 return lws_tls_fake_POLLIN_for_buffered(pt);
578 }
579
580 const struct lws_tls_ops tls_ops_openssl = {
581 /* fake_POLLIN_for_buffered */ tops_fake_POLLIN_for_buffered_openssl,
582 };
583