FreeRDP
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libfreerdp/crypto/tls.c
1
22#include <freerdp/config.h>
23
24#include "../core/settings.h"
25
26#include <winpr/assert.h>
27#include <string.h>
28#include <errno.h>
29
30#include <winpr/crt.h>
31#include <winpr/winpr.h>
32#include <winpr/string.h>
33#include <winpr/sspi.h>
34#include <winpr/ssl.h>
35#include <winpr/json.h>
36
37#include <winpr/stream.h>
38#include <freerdp/utils/ringbuffer.h>
39
40#include <freerdp/crypto/certificate.h>
41#include <freerdp/crypto/certificate_data.h>
42#include <freerdp/utils/helpers.h>
43
44#include <freerdp/log.h>
45#include "../crypto/tls.h"
46#include "../core/tcp.h"
47
48#include "opensslcompat.h"
49#include "certificate.h"
50#include "privatekey.h"
51#include "../core/utils.h"
52
53#ifdef WINPR_HAVE_POLL_H
54#include <poll.h>
55#endif
56
57#ifdef FREERDP_HAVE_VALGRIND_MEMCHECK_H
58#include <valgrind/memcheck.h>
59#endif
60
61#define TAG FREERDP_TAG("crypto")
62
85typedef struct
86{
87 SSL* ssl;
89#ifdef WITH_TLS_DATA_LIMIT
90 UINT64 rxBytes; /* plaintext bytes read since the last rekey */
91 UINT64 txBytes; /* plaintext bytes written since the last rekey */
92 BOOL rekeyAvailable; /* FALSE once we learn the connection is not TLS 1.3 */
93 BOOL cutPending; /* TRUE once a TLS 1.3 rekey failed; tear the connection down */
94#endif
95} BIO_RDP_TLS;
96
97#ifdef WITH_TLS_DATA_LIMIT
98/* Per-direction plaintext byte threshold before refreshing the TLS traffic keys,
99 * to stay within AEAD cryptographic limits. RFC 8446 (TLS 1.3) ยง5.5 bounds
100 * AES-GCM at 2^24.5 records (2^14 B) (~362 GiB). OpenSSL does not enforce this itself
101 * (https://github.com/openssl/openssl/issues/23566). On TLS 1.3 the keys are
102 * rekeyed in place (SSL_key_update); on other protocols a rekey is not possible. */
103static const UINT64 TLS_DATA_LIMIT_BYTES = 388736063996ULL;
104#endif
105
106static INIT_ONCE g_BioMethodsOnce = INIT_ONCE_STATIC_INIT;
107static BIO_METHOD* g_BioMethods = nullptr;
108
109static INIT_ONCE secrets_file_idx_once = INIT_ONCE_STATIC_INIT;
110static int secrets_file_idx = -1;
111
112WINPR_ATTR_NODISCARD
113static int tls_verify_certificate(rdpTls* tls, const rdpCertificate* cert, const char* hostname,
114 UINT16 port);
115
116static void tls_print_certificate_name_mismatch_error(const rdpCertificate* cert,
117 const char* hostname, UINT16 port);
118
119static void tls_print_new_certificate_warn(rdpCertificateStore* store, const char* hostname,
120 UINT16 port, const char* type, const char* fingerprint);
121
122static void tls_print_certificate_error(rdpCertificateStore* store, rdpCertificateData* stored_data,
123 const char* hostname, UINT16 port, const char* fingerprint);
124
125static void free_tls_public_key(rdpTls* tls)
126{
127 WINPR_ASSERT(tls);
128 free(tls->PublicKey);
129 tls->PublicKey = nullptr;
130 tls->PublicKeyLength = 0;
131}
132
133static void free_tls_bindings(SecPkgContext_Bindings* bindings)
134{
135 if (!bindings)
136 return;
137
138 free(bindings->Bindings);
139 free(bindings);
140}
141
142#ifdef WITH_TLS_DATA_LIMIT
143/* Must be called with tls->lock held, after a successful SSL_read/SSL_write of
144 * `count` bytes in the given direction. Once a per-direction byte threshold is
145 * crossed, refreshes the TLS 1.3 traffic keys in place; on a non-TLS-1.3
146 * connection a rekey is not possible so it is disabled (the connection is kept).
147 * If a TLS 1.3 rekey fails, flags the connection to be cut. */
148static void bio_rdp_tls_account(BIO_RDP_TLS* tls, BOOL read, int count)
149{
150 UINT64* counter = read ? &tls->rxBytes : &tls->txBytes;
151
152 if (!tls->rekeyAvailable || tls->cutPending)
153 return;
154
155 *counter += (UINT64)count;
156 if (*counter < TLS_DATA_LIMIT_BYTES)
157 return;
158
159 if (SSL_version(tls->ssl) != TLS1_3_VERSION)
160 {
161 WLog_DBG(TAG, "TLS data limit reached but connection is not TLS 1.3; "
162 "rekey unavailable, keeping connection");
163 tls->rekeyAvailable = FALSE;
164 return;
165 }
166
167 if (SSL_key_update(tls->ssl, SSL_KEY_UPDATE_REQUESTED) != 1)
168 {
169 WLog_ERR(TAG, "SSL_key_update failed at TLS data limit; cutting connection");
170 tls->cutPending = TRUE;
171 return;
172 }
173
174 WLog_INFO(TAG, "TLS 1.3 key update requested at data limit (%" PRIu64 " bytes %s)", *counter,
175 read ? "read" : "written");
176 *counter = 0;
177}
178
179static void bio_rdp_tls_read_account(BIO_RDP_TLS* tls, int count)
180{
181 bio_rdp_tls_account(tls, TRUE, count);
182}
183
184static void bio_rdp_tls_write_account(BIO_RDP_TLS* tls, int count)
185{
186 bio_rdp_tls_account(tls, FALSE, count);
187}
188#endif
189
190WINPR_ATTR_NODISCARD
191static int bio_rdp_tls_write(BIO* bio, const char* buf, int size)
192{
193 int error = 0;
194 int status = 0;
195 BIO_RDP_TLS* tls = (BIO_RDP_TLS*)BIO_get_data(bio);
196
197 if (!buf || !tls)
198 return 0;
199
200#ifdef WITH_TLS_DATA_LIMIT
201 if (tls->cutPending)
202 {
203 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
204 return -1;
205 }
206#endif
207
208 BIO_clear_flags(bio, BIO_FLAGS_WRITE | BIO_FLAGS_READ | BIO_FLAGS_IO_SPECIAL);
209 BIO_clear_retry_flags(bio);
210 EnterCriticalSection(&tls->lock);
211 status = SSL_write(tls->ssl, buf, size);
212 error = SSL_get_error(tls->ssl, status);
213#ifdef WITH_TLS_DATA_LIMIT
214 if (status > 0)
215 bio_rdp_tls_write_account(tls, status);
216#endif
217 LeaveCriticalSection(&tls->lock);
218
219 if (status <= 0)
220 {
221 switch (error)
222 {
223 case SSL_ERROR_NONE:
224 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
225 break;
226
227 case SSL_ERROR_WANT_WRITE:
228 BIO_set_flags(bio, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
229 break;
230
231 case SSL_ERROR_WANT_READ:
232 BIO_set_flags(bio, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
233 break;
234
235 case SSL_ERROR_WANT_X509_LOOKUP:
236 BIO_set_flags(bio, BIO_FLAGS_IO_SPECIAL);
237 BIO_set_retry_reason(bio, BIO_RR_SSL_X509_LOOKUP);
238 break;
239
240 case SSL_ERROR_WANT_CONNECT:
241 BIO_set_flags(bio, BIO_FLAGS_IO_SPECIAL);
242 BIO_set_retry_reason(bio, BIO_RR_CONNECT);
243 break;
244
245 case SSL_ERROR_SYSCALL:
246 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
247 break;
248
249 case SSL_ERROR_SSL:
250 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
251 break;
252 default:
253 break;
254 }
255 }
256
257 return status;
258}
259
260WINPR_ATTR_NODISCARD
261static int bio_rdp_tls_read(BIO* bio, char* buf, int size)
262{
263 int error = 0;
264 int status = 0;
265 BIO_RDP_TLS* tls = (BIO_RDP_TLS*)BIO_get_data(bio);
266
267 if (!buf || !tls)
268 return 0;
269
270#ifdef WITH_TLS_DATA_LIMIT
271 if (tls->cutPending)
272 {
273 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
274 return -1;
275 }
276#endif
277
278 BIO_clear_flags(bio, BIO_FLAGS_WRITE | BIO_FLAGS_READ | BIO_FLAGS_IO_SPECIAL);
279 BIO_clear_retry_flags(bio);
280 EnterCriticalSection(&tls->lock);
281 status = SSL_read(tls->ssl, buf, size);
282 error = SSL_get_error(tls->ssl, status);
283#ifdef WITH_TLS_DATA_LIMIT
284 if (status > 0)
285 bio_rdp_tls_read_account(tls, status);
286#endif
287 LeaveCriticalSection(&tls->lock);
288
289 if (status <= 0)
290 {
291
292 switch (error)
293 {
294 case SSL_ERROR_NONE:
295 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
296 break;
297
298 case SSL_ERROR_WANT_READ:
299 BIO_set_flags(bio, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
300 break;
301
302 case SSL_ERROR_WANT_WRITE:
303 BIO_set_flags(bio, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
304 break;
305
306 case SSL_ERROR_WANT_X509_LOOKUP:
307 BIO_set_flags(bio, BIO_FLAGS_IO_SPECIAL);
308 BIO_set_retry_reason(bio, BIO_RR_SSL_X509_LOOKUP);
309 break;
310
311 case SSL_ERROR_WANT_ACCEPT:
312 BIO_set_flags(bio, BIO_FLAGS_IO_SPECIAL);
313 BIO_set_retry_reason(bio, BIO_RR_ACCEPT);
314 break;
315
316 case SSL_ERROR_WANT_CONNECT:
317 BIO_set_flags(bio, BIO_FLAGS_IO_SPECIAL);
318 BIO_set_retry_reason(bio, BIO_RR_CONNECT);
319 break;
320
321 case SSL_ERROR_SSL:
322 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
323 break;
324
325 case SSL_ERROR_ZERO_RETURN:
326 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
327 break;
328
329 case SSL_ERROR_SYSCALL:
330 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
331 break;
332 default:
333 break;
334 }
335 }
336
337#ifdef FREERDP_HAVE_VALGRIND_MEMCHECK_H
338
339 if (status > 0)
340 {
341 VALGRIND_MAKE_MEM_DEFINED(buf, status);
342 }
343
344#endif
345 return status;
346}
347
348WINPR_ATTR_NODISCARD
349static int bio_rdp_tls_puts(BIO* bio, const char* str)
350{
351 if (!str)
352 return 0;
353
354 const size_t max = (INT_MAX > SIZE_MAX) ? SIZE_MAX : INT_MAX;
355 const size_t size = strnlen(str, max);
356 if (size >= max)
357 return -1;
358 ERR_clear_error();
359 return BIO_write(bio, str, (int)size);
360}
361
362WINPR_ATTR_NODISCARD
363static int bio_rdp_tls_gets(WINPR_ATTR_UNUSED BIO* bio, WINPR_ATTR_UNUSED char* str,
364 WINPR_ATTR_UNUSED int size)
365{
366 return 1;
367}
368
369WINPR_ATTR_NODISCARD
370static long bio_rdp_tls_ctrl(BIO* bio, int cmd, long num, void* ptr)
371{
372 BIO* ssl_rbio = nullptr;
373 BIO* ssl_wbio = nullptr;
374 BIO* next_bio = nullptr;
375 long status = -1;
376 BIO_RDP_TLS* tls = (BIO_RDP_TLS*)BIO_get_data(bio);
377
378 if (!tls)
379 return 0;
380
381 if (!tls->ssl && (cmd != BIO_C_SET_SSL))
382 return 0;
383
384 next_bio = BIO_next(bio);
385 ssl_rbio = tls->ssl ? SSL_get_rbio(tls->ssl) : nullptr;
386 ssl_wbio = tls->ssl ? SSL_get_wbio(tls->ssl) : nullptr;
387
388 switch (cmd)
389 {
390 case BIO_CTRL_RESET:
391 SSL_shutdown(tls->ssl);
392
393 if (SSL_in_connect_init(tls->ssl))
394 SSL_set_connect_state(tls->ssl);
395 else if (SSL_in_accept_init(tls->ssl))
396 SSL_set_accept_state(tls->ssl);
397
398 SSL_clear(tls->ssl);
399
400 if (next_bio)
401 status = BIO_ctrl(next_bio, cmd, num, ptr);
402 else if (ssl_rbio)
403 status = BIO_ctrl(ssl_rbio, cmd, num, ptr);
404 else
405 status = 1;
406
407 break;
408
409 case BIO_C_GET_FD:
410 status = BIO_ctrl(ssl_rbio, cmd, num, ptr);
411 break;
412
413 case BIO_CTRL_INFO:
414 status = 0;
415 break;
416
417 case BIO_CTRL_SET_CALLBACK:
418 status = 0;
419 break;
420
421 case BIO_CTRL_GET_CALLBACK:
422 /* The OpenSSL API is horrible here:
423 * we get a function pointer returned and have to cast it to ULONG_PTR
424 * to return the value to the caller.
425 *
426 * This, of course, is something compilers warn about. So silence it by casting */
427 {
428 void* vptr = WINPR_FUNC_PTR_CAST(SSL_get_info_callback(tls->ssl), void*);
429 *((void**)ptr) = vptr;
430 status = 1;
431 }
432 break;
433
434 case BIO_C_SSL_MODE:
435 if (num)
436 SSL_set_connect_state(tls->ssl);
437 else
438 SSL_set_accept_state(tls->ssl);
439
440 status = 1;
441 break;
442
443 case BIO_CTRL_GET_CLOSE:
444 status = BIO_get_shutdown(bio);
445 break;
446
447 case BIO_CTRL_SET_CLOSE:
448 BIO_set_shutdown(bio, (int)num);
449 status = 1;
450 break;
451
452 case BIO_CTRL_WPENDING:
453 EnterCriticalSection(&tls->lock);
454 status = BIO_ctrl(ssl_wbio, cmd, num, ptr);
455 LeaveCriticalSection(&tls->lock);
456 break;
457
458 case BIO_CTRL_PENDING:
459 status = SSL_pending(tls->ssl);
460
461 if (status == 0)
462 status = BIO_pending(ssl_rbio);
463
464 break;
465
466 case BIO_CTRL_FLUSH:
467 BIO_clear_retry_flags(bio);
468 /* A flush writes out the BIO below, just like SSL_write and SSL_read do,
469 * so it must be serialized with them by the same lock. */
470 EnterCriticalSection(&tls->lock);
471 status = BIO_ctrl(ssl_wbio, cmd, num, ptr);
472 LeaveCriticalSection(&tls->lock);
473 if (status != 1)
474 WLog_DBG(TAG, "BIO_ctrl returned %ld", status);
475 BIO_copy_next_retry(bio);
476 status = 1;
477 break;
478
479 case BIO_CTRL_PUSH:
480 if (next_bio && (next_bio != ssl_rbio))
481 {
482#if OPENSSL_VERSION_NUMBER < 0x10100000L || \
483 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x2070000fL)
484 SSL_set_bio(tls->ssl, next_bio, next_bio);
485 CRYPTO_add(&(bio->next_bio->references), 1, CRYPTO_LOCK_BIO);
486#else
487 /*
488 * We are going to pass ownership of next to the SSL object...but
489 * we don't own a reference to pass yet - so up ref
490 */
491 BIO_up_ref(next_bio);
492 SSL_set_bio(tls->ssl, next_bio, next_bio);
493#endif
494 }
495
496 status = 1;
497 break;
498
499 case BIO_CTRL_POP:
500
501 /* Only detach if we are the BIO explicitly being popped */
502 if (bio == ptr)
503 {
504 if (ssl_rbio != ssl_wbio)
505 BIO_free_all(ssl_wbio);
506
507#if OPENSSL_VERSION_NUMBER < 0x10100000L || \
508 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x2070000fL)
509
510 if (next_bio)
511 CRYPTO_add(&(bio->next_bio->references), -1, CRYPTO_LOCK_BIO);
512
513 tls->ssl->wbio = tls->ssl->rbio = nullptr;
514#else
515 /* OpenSSL 1.1: This will also clear the reference we obtained during push */
516 SSL_set_bio(tls->ssl, nullptr, nullptr);
517#endif
518 }
519
520 status = 1;
521 break;
522
523 case BIO_C_GET_SSL:
524 if (ptr)
525 {
526 *((SSL**)ptr) = tls->ssl;
527 status = 1;
528 }
529
530 break;
531
532 case BIO_C_SET_SSL:
533 BIO_set_shutdown(bio, (int)num);
534
535 if (ptr)
536 {
537 tls->ssl = (SSL*)ptr;
538 ssl_rbio = SSL_get_rbio(tls->ssl);
539 }
540
541 if (ssl_rbio)
542 {
543 if (next_bio)
544 BIO_push(ssl_rbio, next_bio);
545
546 BIO_set_next(bio, ssl_rbio);
547#if OPENSSL_VERSION_NUMBER < 0x10100000L || \
548 (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x2070000fL)
549 CRYPTO_add(&(ssl_rbio->references), 1, CRYPTO_LOCK_BIO);
550#else
551 BIO_up_ref(ssl_rbio);
552#endif
553 }
554
555 BIO_set_init(bio, 1);
556 status = 1;
557 break;
558
559 case BIO_C_DO_STATE_MACHINE:
560 BIO_clear_flags(bio, BIO_FLAGS_READ | BIO_FLAGS_WRITE | BIO_FLAGS_IO_SPECIAL);
561 BIO_set_retry_reason(bio, 0);
562 status = SSL_do_handshake(tls->ssl);
563
564 if (status <= 0)
565 {
566 const int err = (status < INT32_MIN) ? INT32_MIN : (int)status;
567 switch (SSL_get_error(tls->ssl, err))
568 {
569 case SSL_ERROR_WANT_READ:
570 BIO_set_flags(bio, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
571 break;
572
573 case SSL_ERROR_WANT_WRITE:
574 BIO_set_flags(bio, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
575 break;
576
577 case SSL_ERROR_WANT_CONNECT:
578 BIO_set_flags(bio, BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY);
579 BIO_set_retry_reason(bio, BIO_get_retry_reason(next_bio));
580 break;
581
582 default:
583 BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
584 break;
585 }
586 }
587
588 break;
589
590 default:
591 status = BIO_ctrl(ssl_rbio, cmd, num, ptr);
592 break;
593 }
594
595 return status;
596}
597
598WINPR_ATTR_NODISCARD
599static int bio_rdp_tls_new(BIO* bio)
600{
601 BIO_RDP_TLS* tls = nullptr;
602 BIO_set_flags(bio, BIO_FLAGS_SHOULD_RETRY);
603
604 if (!(tls = calloc(1, sizeof(BIO_RDP_TLS))))
605 return 0;
606
607 if (!InitializeCriticalSectionAndSpinCount(&tls->lock, 4000))
608 {
609 free(tls);
610 return -1;
611 }
612
613#ifdef WITH_TLS_DATA_LIMIT
614 /* counters/cutPending zeroed by calloc; rekey is assumed possible until we
615 * observe a non-TLS-1.3 connection at the data limit. */
616 tls->rekeyAvailable = TRUE;
617#endif
618
619 BIO_set_data(bio, (void*)tls);
620 return 1;
621}
622
623WINPR_ATTR_NODISCARD
624static int bio_rdp_tls_free(BIO* bio)
625{
626 BIO_RDP_TLS* tls = nullptr;
627
628 if (!bio)
629 return 0;
630
631 tls = (BIO_RDP_TLS*)BIO_get_data(bio);
632
633 if (!tls)
634 return 0;
635
636 BIO_set_data(bio, nullptr);
637 if (BIO_get_shutdown(bio))
638 {
639 if (BIO_get_init(bio) && tls->ssl)
640 {
641 SSL_shutdown(tls->ssl);
642 SSL_free(tls->ssl);
643 }
644
645 BIO_set_init(bio, 0);
646 BIO_set_flags(bio, 0);
647 }
648
649 DeleteCriticalSection(&tls->lock);
650 free(tls);
651
652 return 1;
653}
654
655WINPR_ATTR_NODISCARD
656static long bio_rdp_tls_callback_ctrl(BIO* bio, int cmd, bio_info_cb* fp)
657{
658 long status = 0;
659
660 if (!bio)
661 return 0;
662
663 BIO_RDP_TLS* tls = (BIO_RDP_TLS*)BIO_get_data(bio);
664
665 if (!tls)
666 return 0;
667
668 switch (cmd)
669 {
670 case BIO_CTRL_SET_CALLBACK:
671 {
672 typedef void (*fkt_t)(const SSL*, int, int);
673
674 /* Documented since https://www.openssl.org/docs/man1.1.1/man3/BIO_set_callback.html
675 * the argument is not really of type bio_info_cb* and must be cast
676 * to the required type */
677
678 fkt_t fkt = WINPR_FUNC_PTR_CAST(fp, fkt_t);
679 SSL_set_info_callback(tls->ssl, fkt);
680 status = 1;
681 }
682 break;
683
684 default:
685 status = BIO_callback_ctrl(SSL_get_rbio(tls->ssl), cmd, fp);
686 break;
687 }
688
689 return status;
690}
691
692#define BIO_TYPE_RDP_TLS 68
693
694WINPR_ATTR_NODISCARD
695static BOOL CALLBACK bio_rdp_tls_init_once(WINPR_ATTR_UNUSED PINIT_ONCE once,
696 WINPR_ATTR_UNUSED PVOID param,
697 WINPR_ATTR_UNUSED PVOID* context)
698{
699 g_BioMethods = BIO_meth_new(BIO_TYPE_RDP_TLS, "RdpTls");
700 if (!g_BioMethods)
701 return FALSE;
702
703 if (BIO_meth_set_write(g_BioMethods, bio_rdp_tls_write) != 1)
704 return FALSE;
705 if (BIO_meth_set_read(g_BioMethods, bio_rdp_tls_read) != 1)
706 return FALSE;
707 if (BIO_meth_set_puts(g_BioMethods, bio_rdp_tls_puts) != 1)
708 return FALSE;
709 if (BIO_meth_set_gets(g_BioMethods, bio_rdp_tls_gets) != 1)
710 return FALSE;
711 if (BIO_meth_set_ctrl(g_BioMethods, bio_rdp_tls_ctrl) != 1)
712 return FALSE;
713 if (BIO_meth_set_create(g_BioMethods, bio_rdp_tls_new) != 1)
714 return FALSE;
715 if (BIO_meth_set_destroy(g_BioMethods, bio_rdp_tls_free) != 1)
716 return FALSE;
717 if (BIO_meth_set_callback_ctrl(g_BioMethods, bio_rdp_tls_callback_ctrl) != 1)
718 return FALSE;
719
720 return TRUE;
721}
722
723WINPR_ATTR_NODISCARD
724static BIO_METHOD* BIO_s_rdp_tls(void)
725{
726 if (!InitOnceExecuteOnce(&g_BioMethodsOnce, bio_rdp_tls_init_once, nullptr, nullptr))
727 return nullptr;
728 return g_BioMethods;
729}
730
731WINPR_ATTR_MALLOC(BIO_free, 1)
732static BIO* BIO_new_rdp_tls(SSL_CTX* ctx, int client)
733{
734 BIO* bio = BIO_new(BIO_s_rdp_tls());
735
736 if (!bio)
737 return nullptr;
738
739 SSL* ssl = SSL_new(ctx);
740
741 if (!ssl)
742 {
743 BIO_free_all(bio);
744 return nullptr;
745 }
746
747 if (client)
748 SSL_set_connect_state(ssl);
749 else
750 SSL_set_accept_state(ssl);
751
752 BIO_set_ssl(bio, ssl, BIO_CLOSE);
753 return bio;
754}
755
756WINPR_ATTR_MALLOC(freerdp_certificate_free, 1)
757static rdpCertificate* tls_get_certificate(rdpTls* tls, BOOL peer)
758{
759 X509* remote_cert = nullptr;
760
761 if (peer)
762 remote_cert = SSL_get_peer_certificate(tls->ssl);
763 else
764 remote_cert = X509_dup(SSL_get_certificate(tls->ssl));
765
766 if (!remote_cert)
767 {
768 WLog_ERR(TAG, "failed to get the server TLS certificate");
769 return nullptr;
770 }
771
772 /* Get the peer's chain. If it does not exist, we're setting nullptr (clean data either way) */
773 STACK_OF(X509)* chain = SSL_get_peer_cert_chain(tls->ssl);
774 rdpCertificate* cert = freerdp_certificate_new_from_x509(remote_cert, chain);
775 X509_free(remote_cert);
776
777 return cert;
778}
779
780WINPR_ATTR_NODISCARD
781static const char* tls_get_server_name(rdpTls* tls)
782{
783 return tls->serverName ? tls->serverName : tls->hostname;
784}
785
786#define TLS_SERVER_END_POINT "tls-server-end-point:"
787
788WINPR_ATTR_MALLOC(free_tls_bindings, 1)
789static SecPkgContext_Bindings* tls_get_channel_bindings(const rdpCertificate* cert)
790{
791 size_t CertificateHashLength = 0;
792 BYTE* ChannelBindingToken = nullptr;
793 SEC_CHANNEL_BINDINGS* ChannelBindings = nullptr;
794 const size_t PrefixLength = strnlen(TLS_SERVER_END_POINT, ARRAYSIZE(TLS_SERVER_END_POINT));
795
796 WINPR_ASSERT(cert);
797
798 /* See https://www.rfc-editor.org/rfc/rfc5929 for details about hashes */
799 WINPR_MD_TYPE alg = freerdp_certificate_get_signature_alg(cert);
800 const char* hash = nullptr;
801 switch (alg)
802 {
803
804 case WINPR_MD_MD5:
805 case WINPR_MD_SHA1:
806 hash = winpr_md_type_to_string(WINPR_MD_SHA256);
807 break;
808 default:
809 hash = winpr_md_type_to_string(alg);
810 break;
811 }
812 if (!hash)
813 return nullptr;
814
815 char* CertificateHash = freerdp_certificate_get_hash(cert, hash, &CertificateHashLength);
816 if (!CertificateHash)
817 return nullptr;
818
819 const size_t ChannelBindingTokenLength = PrefixLength + CertificateHashLength;
820 SecPkgContext_Bindings* ContextBindings = calloc(1, sizeof(SecPkgContext_Bindings));
821
822 if (!ContextBindings)
823 goto out_free;
824
825 {
826 const size_t slen = sizeof(SEC_CHANNEL_BINDINGS) + ChannelBindingTokenLength;
827 if (slen > UINT32_MAX)
828 goto out_free;
829
830 ContextBindings->BindingsLength = (UINT32)slen;
831 }
832 ChannelBindings = (SEC_CHANNEL_BINDINGS*)calloc(1, ContextBindings->BindingsLength);
833
834 if (!ChannelBindings)
835 goto out_free;
836
837 ContextBindings->Bindings = ChannelBindings;
838 ChannelBindings->cbApplicationDataLength = (UINT32)ChannelBindingTokenLength;
839 ChannelBindings->dwApplicationDataOffset = sizeof(SEC_CHANNEL_BINDINGS);
840 ChannelBindingToken = &((BYTE*)ChannelBindings)[ChannelBindings->dwApplicationDataOffset];
841 memcpy(ChannelBindingToken, TLS_SERVER_END_POINT, PrefixLength);
842 memcpy(ChannelBindingToken + PrefixLength, CertificateHash, CertificateHashLength);
843 free(CertificateHash);
844 return ContextBindings;
845out_free:
846 free(CertificateHash);
847 free(ContextBindings);
848 return nullptr;
849}
850
851WINPR_ATTR_NODISCARD
852static BOOL CALLBACK secrets_file_init_cb(WINPR_ATTR_UNUSED PINIT_ONCE once,
853 WINPR_ATTR_UNUSED PVOID param,
854 WINPR_ATTR_UNUSED PVOID* context)
855{
856 secrets_file_idx = SSL_get_ex_new_index(0, nullptr, nullptr, nullptr, nullptr);
857
858 return (secrets_file_idx != -1);
859}
860
861static void SSLCTX_keylog_cb(const SSL* ssl, const char* line)
862{
863 char* dfile = nullptr;
864
865 if (secrets_file_idx == -1)
866 return;
867
868 dfile = SSL_get_ex_data(ssl, secrets_file_idx);
869 if (dfile)
870 {
871 FILE* f = winpr_fopen(dfile, "a+");
872 if (f)
873 {
874 (void)fwrite(line, strlen(line), 1, f);
875 (void)fwrite("\n", 1, 1, f);
876 (void)fclose(f);
877 }
878 }
879}
880
881static void tls_reset(rdpTls* tls)
882{
883 WINPR_ASSERT(tls);
884
885 if (tls->ctx)
886 {
887 SSL_CTX_free(tls->ctx);
888 tls->ctx = nullptr;
889 }
890
891 /* tls->underlying is a stacked BIO under tls->bio.
892 * BIO_free_all will free recursively. */
893 if (tls->bio)
894 BIO_free_all(tls->bio);
895 else if (tls->underlying)
896 BIO_free_all(tls->underlying);
897 tls->bio = nullptr;
898 tls->underlying = nullptr;
899
900 free_tls_public_key(tls);
901 free_tls_bindings(tls->Bindings);
902 tls->Bindings = nullptr;
903}
904
905#if OPENSSL_VERSION_NUMBER >= 0x010000000L
906WINPR_ATTR_NODISCARD
907static BOOL tls_prepare(rdpTls* tls, BIO* underlying, const SSL_METHOD* method, int options,
908 BOOL clientMode)
909#else
910WINPR_ATTR_NODISCARD
911static BOOL tls_prepare(rdpTls* tls, BIO* underlying, SSL_METHOD* method, int options,
912 BOOL clientMode)
913#endif
914{
915 WINPR_ASSERT(tls);
916
917 rdpSettings* settings = tls->context->settings;
918 WINPR_ASSERT(settings);
919
920 tls_reset(tls);
921 tls->ctx = SSL_CTX_new(method);
922
923 tls->underlying = underlying;
924
925 if (!tls->ctx)
926 {
927 WLog_ERR(TAG, "SSL_CTX_new failed");
928 return FALSE;
929 }
930
931 SSL_CTX_set_mode(tls->ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | SSL_MODE_ENABLE_PARTIAL_WRITE);
932 SSL_CTX_set_options(tls->ctx, WINPR_ASSERTING_INT_CAST(uint64_t, options));
933 SSL_CTX_set_read_ahead(tls->ctx, 1);
934#if OPENSSL_VERSION_NUMBER >= 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
935 UINT16 version = freerdp_settings_get_uint16(settings, FreeRDP_TLSMinVersion);
936 if (!SSL_CTX_set_min_proto_version(tls->ctx, version))
937 {
938 WLog_ERR(TAG, "SSL_CTX_set_min_proto_version %" PRIu16 " failed", version);
939 return FALSE;
940 }
941 version = freerdp_settings_get_uint16(settings, FreeRDP_TLSMaxVersion);
942 if (!SSL_CTX_set_max_proto_version(tls->ctx, version))
943 {
944 WLog_ERR(TAG, "SSL_CTX_set_max_proto_version %" PRIu16 " failed", version);
945 return FALSE;
946 }
947#endif
948#if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
949 SSL_CTX_set_security_level(tls->ctx, WINPR_ASSERTING_INT_CAST(int, settings->TlsSecLevel));
950#endif
951
952 if (settings->AllowedTlsCiphers)
953 {
954 if (!SSL_CTX_set_cipher_list(tls->ctx, settings->AllowedTlsCiphers))
955 {
956 WLog_ERR(TAG, "SSL_CTX_set_cipher_list %s failed", settings->AllowedTlsCiphers);
957 return FALSE;
958 }
959 }
960
961 tls->bio = BIO_new_rdp_tls(tls->ctx, clientMode);
962
963 if (!tls->bio)
964 {
965 WLog_ERR(TAG, "unable to create TLS BIO");
966 return FALSE;
967 }
968
969 if (BIO_get_ssl(tls->bio, &tls->ssl) < 0 || !tls->ssl)
970 {
971 WLog_ERR(TAG, "unable to retrieve the SSL of the connection");
972 return FALSE;
973 }
974
975 if (settings->TlsSecretsFile)
976 {
977#if OPENSSL_VERSION_NUMBER >= 0x10101000L
978 if (!InitOnceExecuteOnce(&secrets_file_idx_once, secrets_file_init_cb, nullptr, nullptr))
979 return FALSE;
980
981 if (secrets_file_idx != -1)
982 {
983 SSL_set_ex_data(tls->ssl, secrets_file_idx, settings->TlsSecretsFile);
984 SSL_CTX_set_keylog_callback(tls->ctx, SSLCTX_keylog_cb);
985 }
986#else
987 WLog_WARN(TAG, "Key-Logging not available - requires OpenSSL 1.1.1 or higher");
988#endif
989 }
990
991 BIO_push(tls->bio, underlying);
992 return TRUE;
993}
994
995static void
996adjustSslOptions(WINPR_ATTR_UNUSED int* options) // NOLINT(readability-non-const-parameter)
997{
998 WINPR_ASSERT(options);
999#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
1000 *options |= SSL_OP_NO_SSLv2;
1001 *options |= SSL_OP_NO_SSLv3;
1002#endif
1003}
1004
1005const SSL_METHOD* freerdp_tls_get_ssl_method(BOOL isDtls, BOOL isClient)
1006{
1007 if (isClient)
1008 {
1009 if (isDtls)
1010 return DTLS_client_method();
1011#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
1012 return SSLv23_client_method();
1013#else
1014 return TLS_client_method();
1015#endif
1016 }
1017
1018 if (isDtls)
1019 return DTLS_server_method();
1020
1021#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
1022 return SSLv23_server_method();
1023#else
1024 return TLS_server_method();
1025#endif
1026}
1027
1028TlsHandshakeResult freerdp_tls_connect_ex(rdpTls* tls, BIO* underlying, const SSL_METHOD* methods)
1029{
1030 WINPR_ASSERT(tls);
1031
1032 int options = 0;
1042#ifdef SSL_OP_NO_COMPRESSION
1043 options |= SSL_OP_NO_COMPRESSION;
1044#endif
1051 options |= SSL_OP_TLS_BLOCK_PADDING_BUG;
1058 options |= SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS;
1059
1060 tls->isClientMode = TRUE;
1061 adjustSslOptions(&options);
1062
1063 if (!tls_prepare(tls, underlying, methods, options, TRUE))
1064 return TLS_HANDSHAKE_ERROR;
1065
1066#if !defined(OPENSSL_NO_TLSEXT)
1067 const char* str = tls_get_server_name(tls);
1068 void* ptr = WINPR_CAST_CONST_PTR_AWAY(str, void*);
1069 SSL_set_tlsext_host_name(tls->ssl, ptr);
1070#endif
1071
1072 return freerdp_tls_handshake(tls);
1073}
1074
1075static int bio_err_print(const char* str, size_t len, void* u)
1076{
1077 wLog* log = u;
1078 WLog_Print(log, WLOG_ERROR, "[BIO_do_handshake] %s [%" PRIuz "]", str, len);
1079 return 0;
1080}
1081
1082TlsHandshakeResult freerdp_tls_handshake(rdpTls* tls)
1083{
1084 TlsHandshakeResult ret = TLS_HANDSHAKE_ERROR;
1085
1086 WINPR_ASSERT(tls);
1087 const long status = BIO_do_handshake(tls->bio);
1088 if (status != 1)
1089 {
1090 if (!BIO_should_retry(tls->bio))
1091 {
1092 wLog* log = WLog_Get(TAG);
1093 WLog_Print(log, WLOG_ERROR, "BIO_do_handshake failed");
1094 ERR_print_errors_cb(bio_err_print, log);
1095 return TLS_HANDSHAKE_ERROR;
1096 }
1097
1098 return TLS_HANDSHAKE_CONTINUE;
1099 }
1100
1101 int verify_status = 0;
1102 rdpCertificate* cert = tls_get_certificate(tls, tls->isClientMode);
1103
1104 if (!cert)
1105 {
1106 WLog_ERR(TAG, "tls_get_certificate failed to return the server certificate.");
1107 return TLS_HANDSHAKE_ERROR;
1108 }
1109
1110 do
1111 {
1112 free_tls_bindings(tls->Bindings);
1113 tls->Bindings = tls_get_channel_bindings(cert);
1114 if (!tls->Bindings)
1115 {
1116 WLog_ERR(TAG, "unable to retrieve bindings");
1117 break;
1118 }
1119
1120 free_tls_public_key(tls);
1121 if (!freerdp_certificate_get_public_key(cert, &tls->PublicKey, &tls->PublicKeyLength))
1122 {
1123 WLog_ERR(TAG,
1124 "freerdp_certificate_get_public_key failed to return the server public key.");
1125 break;
1126 }
1127
1128 /* server-side NLA needs public keys (keys from us, the server) but no certificate verify */
1129 ret = TLS_HANDSHAKE_SUCCESS;
1130
1131 if (tls->isClientMode)
1132 {
1133 WINPR_ASSERT(tls->port <= UINT16_MAX);
1134 verify_status =
1135 tls_verify_certificate(tls, cert, tls_get_server_name(tls), (UINT16)tls->port);
1136
1137 if (verify_status < 1)
1138 {
1139 WLog_ERR(TAG, "certificate not trusted, aborting.");
1140 freerdp_tls_send_alert(tls);
1141 ret = TLS_HANDSHAKE_VERIFY_ERROR;
1142 }
1143 }
1144 } while (0);
1145
1146 freerdp_certificate_free(cert);
1147 return ret;
1148}
1149
1150static int pollAndHandshake(rdpTls* tls)
1151{
1152 WINPR_ASSERT(tls);
1153
1154 do
1155 {
1156 HANDLE events[] = { freerdp_abort_event(tls->context), nullptr };
1157 DWORD status = 0;
1158 if (BIO_get_event(tls->bio, &events[1]) < 0)
1159 {
1160 WLog_ERR(TAG, "unable to retrieve BIO associated event");
1161 return -1;
1162 }
1163
1164 if (!events[1])
1165 {
1166 WLog_ERR(TAG, "unable to retrieve BIO event");
1167 return -1;
1168 }
1169
1170 status = WaitForMultipleObjectsEx(ARRAYSIZE(events), events, FALSE, INFINITE, TRUE);
1171 switch (status)
1172 {
1173 case WAIT_OBJECT_0 + 1:
1174 break;
1175 case WAIT_OBJECT_0:
1176 WLog_DBG(TAG, "Abort event set, cancel connect");
1177 return -1;
1178 case WAIT_TIMEOUT:
1179 case WAIT_IO_COMPLETION:
1180 continue;
1181 default:
1182 WLog_ERR(TAG, "error during WaitForSingleObject(): 0x%08" PRIX32 "", status);
1183 return -1;
1184 }
1185
1186 TlsHandshakeResult result = freerdp_tls_handshake(tls);
1187 switch (result)
1188 {
1189 case TLS_HANDSHAKE_CONTINUE:
1190 break;
1191 case TLS_HANDSHAKE_SUCCESS:
1192 return 1;
1193 case TLS_HANDSHAKE_ERROR:
1194 case TLS_HANDSHAKE_VERIFY_ERROR:
1195 default:
1196 return -1;
1197 }
1198 } while (TRUE);
1199}
1200
1201int freerdp_tls_connect(rdpTls* tls, BIO* underlying)
1202{
1203 const SSL_METHOD* method = freerdp_tls_get_ssl_method(FALSE, TRUE);
1204
1205 WINPR_ASSERT(tls);
1206 TlsHandshakeResult result = freerdp_tls_connect_ex(tls, underlying, method);
1207 switch (result)
1208 {
1209 case TLS_HANDSHAKE_SUCCESS:
1210 return 1;
1211 case TLS_HANDSHAKE_CONTINUE:
1212 break;
1213 case TLS_HANDSHAKE_ERROR:
1214 case TLS_HANDSHAKE_VERIFY_ERROR:
1215 return -1;
1216 default:
1217 return -1;
1218 }
1219
1220 return pollAndHandshake(tls);
1221}
1222
1223#if defined(MICROSOFT_IOS_SNI_BUG) && !defined(OPENSSL_NO_TLSEXT) && \
1224 !defined(LIBRESSL_VERSION_NUMBER)
1225static void tls_openssl_tlsext_debug_callback(SSL* s, int client_server, int type,
1226 unsigned char* data, int len, void* arg)
1227{
1228 if (type == TLSEXT_TYPE_server_name)
1229 {
1230 WLog_DBG(TAG, "Client uses SNI (extension disabled)");
1231 s->servername_done = 2;
1232 }
1233}
1234#endif
1235
1236BOOL freerdp_tls_accept(rdpTls* tls, BIO* underlying, rdpSettings* settings)
1237{
1238 WINPR_ASSERT(tls);
1239 TlsHandshakeResult res =
1240 freerdp_tls_accept_ex(tls, underlying, settings, freerdp_tls_get_ssl_method(FALSE, FALSE));
1241 switch (res)
1242 {
1243 case TLS_HANDSHAKE_SUCCESS:
1244 return TRUE;
1245 case TLS_HANDSHAKE_CONTINUE:
1246 break;
1247 case TLS_HANDSHAKE_ERROR:
1248 case TLS_HANDSHAKE_VERIFY_ERROR:
1249 default:
1250 return FALSE;
1251 }
1252
1253 return pollAndHandshake(tls) > 0;
1254}
1255
1256TlsHandshakeResult freerdp_tls_accept_ex(rdpTls* tls, BIO* underlying, rdpSettings* settings,
1257 const SSL_METHOD* methods)
1258{
1259 WINPR_ASSERT(tls);
1260
1261 int options = 0;
1262 int status = 0;
1263
1270 options |= SSL_OP_NO_SSLv2;
1280#ifdef SSL_OP_NO_COMPRESSION
1281 options |= SSL_OP_NO_COMPRESSION;
1282#endif
1289 options |= SSL_OP_TLS_BLOCK_PADDING_BUG;
1296 options |= SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS;
1297
1304#if (OPENSSL_VERSION_NUMBER >= 0x10101000L) && (OPENSSL_VERSION_NUMBER < 0x30000000L) && \
1305 !defined(LIBRESSL_VERSION_NUMBER)
1306 options |= SSL_OP_NO_RENEGOTIATION;
1307#endif
1308
1309 if (!tls_prepare(tls, underlying, methods, options, FALSE))
1310 return TLS_HANDSHAKE_ERROR;
1311
1312 const rdpPrivateKey* key = freerdp_settings_get_pointer(settings, FreeRDP_RdpServerRsaKey);
1313 if (!key)
1314 {
1315 WLog_ERR(TAG, "invalid private key");
1316 return TLS_HANDSHAKE_ERROR;
1317 }
1318
1319 EVP_PKEY* privkey = freerdp_key_get_evp_pkey(key);
1320 if (!privkey)
1321 {
1322 WLog_ERR(TAG, "invalid private key");
1323 return TLS_HANDSHAKE_ERROR;
1324 }
1325
1326 status = SSL_use_PrivateKey(tls->ssl, privkey);
1327 /* The local reference to the private key will anyway go out of
1328 * scope; so the reference count should be decremented whether
1329 * SSL_use_PrivateKey succeeds or fails.
1330 */
1331 EVP_PKEY_free(privkey);
1332
1333 if (status <= 0)
1334 {
1335 WLog_ERR(TAG, "SSL_CTX_use_PrivateKey_file failed");
1336 return TLS_HANDSHAKE_ERROR;
1337 }
1338
1339 rdpCertificate* cert =
1340 freerdp_settings_get_pointer_writable(settings, FreeRDP_RdpServerCertificate);
1341 if (!cert)
1342 {
1343 WLog_ERR(TAG, "invalid certificate");
1344 return TLS_HANDSHAKE_ERROR;
1345 }
1346
1347 status = SSL_use_certificate(tls->ssl, freerdp_certificate_get_x509(cert));
1348
1349 if (status <= 0)
1350 {
1351 WLog_ERR(TAG, "SSL_use_certificate_file failed");
1352 return TLS_HANDSHAKE_ERROR;
1353 }
1354
1355 const size_t cnt = freerdp_certificate_get_chain_len(cert);
1356 for (size_t x = 0; x < cnt; x++)
1357 {
1358 X509* xcert = freerdp_certificate_get_chain_at(cert, x);
1359 WINPR_ASSERT(xcert);
1360 const long rc = SSL_add1_chain_cert(tls->ssl, xcert);
1361 if (rc != 1)
1362 {
1363 WLog_ERR(TAG, "SSL_add1_chain_cert failed");
1364 return TLS_HANDSHAKE_ERROR;
1365 }
1366 }
1367
1368#if defined(MICROSOFT_IOS_SNI_BUG) && !defined(OPENSSL_NO_TLSEXT) && \
1369 !defined(LIBRESSL_VERSION_NUMBER)
1370 SSL_set_tlsext_debug_callback(tls->ssl, tls_openssl_tlsext_debug_callback);
1371#endif
1372
1373 return freerdp_tls_handshake(tls);
1374}
1375
1376BOOL freerdp_tls_send_alert(rdpTls* tls)
1377{
1378 WINPR_ASSERT(tls);
1379
1380 if (!tls)
1381 return FALSE;
1382
1383 if (!tls->ssl)
1384 return TRUE;
1385
1390#if (!defined(LIBRESSL_VERSION_NUMBER) && (OPENSSL_VERSION_NUMBER < 0x10100000L)) || \
1391 (defined(LIBRESSL_VERSION_NUMBER) && (LIBRESSL_VERSION_NUMBER <= 0x2080300fL))
1392
1393 if (tls->alertDescription != TLS_ALERT_DESCRIPTION_CLOSE_NOTIFY)
1394 {
1404 SSL_SESSION* ssl_session = SSL_get_session(tls->ssl);
1405 SSL_CTX* ssl_ctx = SSL_get_SSL_CTX(tls->ssl);
1406 SSL_set_quiet_shutdown(tls->ssl, 1);
1407
1408 if ((tls->alertLevel == TLS_ALERT_LEVEL_FATAL) && (ssl_session))
1409 SSL_CTX_remove_session(ssl_ctx, ssl_session);
1410
1411 tls->ssl->s3->alert_dispatch = 1;
1412 tls->ssl->s3->send_alert[0] = tls->alertLevel;
1413 tls->ssl->s3->send_alert[1] = tls->alertDescription;
1414
1415 if (tls->ssl->s3->wbuf.left == 0)
1416 tls->ssl->method->ssl_dispatch_alert(tls->ssl);
1417 }
1418
1419#endif
1420 return TRUE;
1421}
1422
1423int freerdp_tls_write_all(rdpTls* tls, const BYTE* data, size_t length)
1424{
1425 WINPR_ASSERT(tls);
1426 size_t offset = 0;
1427 BIO* bio = tls->bio;
1428
1429 if (length > INT32_MAX)
1430 return -1;
1431
1432 while (offset < length)
1433 {
1434 ERR_clear_error();
1435 const int status = BIO_write(bio, &data[offset], (int)(length - offset));
1436
1437 if (status > 0)
1438 offset += (size_t)status;
1439 else
1440 {
1441 if (!BIO_should_retry(bio))
1442 return -1;
1443
1444 if (BIO_write_blocked(bio))
1445 {
1446 const long rc = BIO_wait_write(bio, 100);
1447 if (rc < 0)
1448 return -1;
1449 }
1450 else if (BIO_read_blocked(bio))
1451 return -2; /* Abort write, there is data that must be read */
1452 else
1453 USleep(100);
1454 }
1455 }
1456
1457 return (int)length;
1458}
1459
1460int freerdp_tls_set_alert_code(rdpTls* tls, int level, int description)
1461{
1462 WINPR_ASSERT(tls);
1463 tls->alertLevel = level;
1464 tls->alertDescription = description;
1465 return 0;
1466}
1467
1468WINPR_ATTR_NODISCARD
1469static BOOL is_redirected(rdpTls* tls)
1470{
1471 rdpSettings* settings = tls->context->settings;
1472
1473 if (settings->GatewayArmTransport)
1474 return TRUE;
1475
1476 if (LB_NOREDIRECT & settings->RedirectionFlags)
1477 return FALSE;
1478
1479 return settings->RedirectionFlags != 0;
1480}
1481
1482WINPR_ATTR_NODISCARD
1483static BOOL is_accepted(rdpTls* tls, const rdpCertificate* cert)
1484{
1485 WINPR_ASSERT(tls);
1486 WINPR_ASSERT(tls->context);
1487 WINPR_ASSERT(cert);
1488 rdpSettings* settings = tls->context->settings;
1489 WINPR_ASSERT(settings);
1490
1491 FreeRDP_Settings_Keys_String keyAccepted = FreeRDP_AcceptedCert;
1492 FreeRDP_Settings_Keys_UInt32 keyLength = FreeRDP_AcceptedCertLength;
1493
1494 if (tls->isGatewayTransport)
1495 {
1496 keyAccepted = FreeRDP_GatewayAcceptedCert;
1497 keyLength = FreeRDP_GatewayAcceptedCertLength;
1498 }
1499 else if (is_redirected(tls))
1500 {
1501 keyAccepted = FreeRDP_RedirectionAcceptedCert;
1502 keyLength = FreeRDP_RedirectionAcceptedCertLength;
1503 }
1504
1505 const char* AcceptedKey = freerdp_settings_get_string(settings, keyAccepted);
1506 const UINT32 AcceptedKeyLength = freerdp_settings_get_uint32(settings, keyLength);
1507
1508 if ((AcceptedKeyLength > 0) && AcceptedKey)
1509 {
1510 BOOL accepted = FALSE;
1511 size_t pemLength = 0;
1512 char* pem = freerdp_certificate_get_pem_ex(cert, &pemLength, FALSE);
1513 if (pem && (AcceptedKeyLength == pemLength))
1514 {
1515 if (memcmp(AcceptedKey, pem, AcceptedKeyLength) == 0)
1516 accepted = TRUE;
1517 }
1518 free(pem);
1519 if (accepted)
1520 return TRUE;
1521 }
1522
1523 if (!freerdp_settings_set_string(settings, keyAccepted, nullptr))
1524 WLog_WARN(TAG, "freerdp_settings_set_string(settings, keyAccepted=%d, nullptr) failed",
1525 keyAccepted);
1526 if (!freerdp_settings_set_uint32(settings, keyLength, 0))
1527 WLog_WARN(TAG, "freerdp_settings_set_uint32(settings, keyLength=%d, 0) failed", keyLength);
1528
1529 return FALSE;
1530}
1531
1532WINPR_ATTR_NODISCARD
1533static BOOL compare_fingerprint(const char* fp, const char* hash, const rdpCertificate* cert,
1534 BOOL separator)
1535{
1536 BOOL equal = 0;
1537 char* strhash = nullptr;
1538
1539 WINPR_ASSERT(fp);
1540 WINPR_ASSERT(hash);
1541 WINPR_ASSERT(cert);
1542
1543 strhash = freerdp_certificate_get_fingerprint_by_hash_ex(cert, hash, separator);
1544 if (!strhash)
1545 return FALSE;
1546
1547 equal = (_stricmp(strhash, fp) == 0);
1548 free(strhash);
1549 return equal;
1550}
1551
1552WINPR_ATTR_NODISCARD
1553static BOOL compare_fingerprint_all(const char* fp, const char* hash, const rdpCertificate* cert)
1554{
1555 WINPR_ASSERT(fp);
1556 WINPR_ASSERT(hash);
1557 WINPR_ASSERT(cert);
1558 if (compare_fingerprint(fp, hash, cert, FALSE))
1559 return TRUE;
1560 if (compare_fingerprint(fp, hash, cert, TRUE))
1561 return TRUE;
1562 return FALSE;
1563}
1564
1565WINPR_ATTR_NODISCARD
1566static BOOL is_accepted_fingerprint(const rdpCertificate* cert,
1567 const char* CertificateAcceptedFingerprints)
1568{
1569 WINPR_ASSERT(cert);
1570
1571 BOOL rc = FALSE;
1572 if (CertificateAcceptedFingerprints)
1573 {
1574 char* context = nullptr;
1575 char* copy = _strdup(CertificateAcceptedFingerprints);
1576 char* cur = strtok_s(copy, ",", &context);
1577 while (cur)
1578 {
1579 char* subcontext = nullptr;
1580 const char* h = strtok_s(cur, ":", &subcontext);
1581
1582 if (!h)
1583 goto next;
1584
1585 {
1586 const char* fp = h + strlen(h) + 1;
1587 if (compare_fingerprint_all(fp, h, cert))
1588 {
1589 rc = TRUE;
1590 break;
1591 }
1592 }
1593 next:
1594 cur = strtok_s(nullptr, ",", &context);
1595 }
1596 free(copy);
1597 }
1598
1599 return rc;
1600}
1601
1602WINPR_ATTR_NODISCARD
1603static BOOL accept_cert(rdpTls* tls, const rdpCertificate* cert)
1604{
1605 WINPR_ASSERT(tls);
1606 WINPR_ASSERT(tls->context);
1607 WINPR_ASSERT(cert);
1608
1609 FreeRDP_Settings_Keys_String id = FreeRDP_AcceptedCert;
1610 FreeRDP_Settings_Keys_UInt32 lid = FreeRDP_AcceptedCertLength;
1611
1612 rdpSettings* settings = tls->context->settings;
1613 WINPR_ASSERT(settings);
1614
1615 if (tls->isGatewayTransport)
1616 {
1617 id = FreeRDP_GatewayAcceptedCert;
1618 lid = FreeRDP_GatewayAcceptedCertLength;
1619 }
1620 else if (is_redirected(tls))
1621 {
1622 id = FreeRDP_RedirectionAcceptedCert;
1623 lid = FreeRDP_RedirectionAcceptedCertLength;
1624 }
1625
1626 size_t pemLength = 0;
1627 char* pem = freerdp_certificate_get_pem_ex(cert, &pemLength, FALSE);
1628 BOOL rc = FALSE;
1629 if (pemLength <= UINT32_MAX)
1630 {
1631 if (freerdp_settings_set_string_len(settings, id, pem, pemLength))
1632 rc = freerdp_settings_set_uint32(settings, lid, (UINT32)pemLength);
1633 }
1634 free(pem);
1635 return rc;
1636}
1637
1638WINPR_ATTR_NODISCARD
1639static BOOL tls_extract_full_pem(const rdpCertificate* cert, BYTE** PublicKey,
1640 size_t* PublicKeyLength)
1641{
1642 if (!cert || !PublicKey)
1643 return FALSE;
1644 *PublicKey = (BYTE*)freerdp_certificate_get_pem(cert, PublicKeyLength);
1645 return *PublicKey != nullptr;
1646}
1647
1648WINPR_ATTR_NODISCARD
1649static int tls_config_parse_bool(WINPR_JSON* json, const char* opt)
1650{
1651 WINPR_JSON* val = WINPR_JSON_GetObjectItemCaseSensitive(json, opt);
1652 if (!val || !WINPR_JSON_IsBool(val))
1653 return -1;
1654
1655 if (WINPR_JSON_IsTrue(val))
1656 return 1;
1657 return 0;
1658}
1659
1660WINPR_ATTR_NODISCARD
1661static int tls_config_check_allowed_hashed(const char* configfile, const rdpCertificate* cert,
1662 WINPR_JSON* json)
1663{
1664 WINPR_ASSERT(configfile);
1665 WINPR_ASSERT(cert);
1666 WINPR_ASSERT(json);
1667
1668 WINPR_JSON* db = WINPR_JSON_GetObjectItemCaseSensitive(json, "certificate-db");
1669 if (!db || !WINPR_JSON_IsArray(db))
1670 return 0;
1671
1672 for (size_t x = 0; x < WINPR_JSON_GetArraySize(db); x++)
1673 {
1674 WINPR_JSON* cur = WINPR_JSON_GetArrayItem(db, x);
1675 if (!cur || !WINPR_JSON_IsObject(cur))
1676 {
1677 WLog_WARN(TAG,
1678 "[%s] invalid certificate-db entry at position %" PRIuz ": not a JSON object",
1679 configfile, x);
1680 continue;
1681 }
1682
1683 WINPR_JSON* key = WINPR_JSON_GetObjectItemCaseSensitive(cur, "type");
1684 if (!key || !WINPR_JSON_IsString(key))
1685 {
1686 WLog_WARN(TAG,
1687 "[%s] invalid certificate-db entry at position %" PRIuz
1688 ": invalid 'type' element, expected type string",
1689 configfile, x);
1690 continue;
1691 }
1692 WINPR_JSON* val = WINPR_JSON_GetObjectItemCaseSensitive(cur, "hash");
1693 if (!val || !WINPR_JSON_IsString(val))
1694 {
1695 WLog_WARN(TAG,
1696 "[%s] invalid certificate-db entry at position %" PRIuz
1697 ": invalid 'hash' element, expected type string",
1698 configfile, x);
1699 continue;
1700 }
1701
1702 const char* skey = WINPR_JSON_GetStringValue(key);
1703 const char* sval = WINPR_JSON_GetStringValue(val);
1704
1705 char* hash = freerdp_certificate_get_fingerprint_by_hash_ex(cert, skey, FALSE);
1706 if (!hash)
1707 {
1708 WLog_WARN(TAG,
1709 "[%s] invalid certificate-db entry at position %" PRIuz
1710 ": hash type '%s' not supported by certificate",
1711 configfile, x, skey);
1712 continue;
1713 }
1714
1715 const int cmp = _stricmp(hash, sval);
1716 free(hash);
1717
1718 if (cmp == 0)
1719 return 1;
1720 }
1721
1722 return 0;
1723}
1724
1725WINPR_ATTR_NODISCARD
1726static int tls_config_check_certificate(const rdpCertificate* cert, BOOL* pAllowUserconfig)
1727{
1728 WINPR_ASSERT(cert);
1729 WINPR_ASSERT(pAllowUserconfig);
1730
1731 int rc = 0;
1732 const char configfile[] = "certificates.json";
1733 WINPR_JSON* json = freerdp_GetJSONConfigFile(TRUE, configfile);
1734
1735 if (!json)
1736 {
1737 WLog_DBG(TAG, "No or no valid configuration file for certificate handling, asking user");
1738 goto fail;
1739 }
1740
1741 if (tls_config_parse_bool(json, "deny") > 0)
1742 {
1743 WLog_WARN(TAG, "[%s] certificate denied by configuration", configfile);
1744 rc = -1;
1745 goto fail;
1746 }
1747
1748 if (tls_config_parse_bool(json, "ignore") > 0)
1749 {
1750 WLog_WARN(TAG, "[%s] certificate ignored by configuration", configfile);
1751 rc = 1;
1752 goto fail;
1753 }
1754
1755 if (tls_config_check_allowed_hashed(configfile, cert, json) > 0)
1756 {
1757 WLog_WARN(TAG, "[%s] certificate manually accepted by configuration", configfile);
1758 rc = 1;
1759 goto fail;
1760 }
1761
1762 if (tls_config_parse_bool(json, "deny-userconfig") > 0)
1763 {
1764 WLog_WARN(TAG, "[%s] configuration denies user to accept certificates", configfile);
1765 rc = -1;
1766 goto fail;
1767 }
1768
1769fail:
1770
1771 *pAllowUserconfig = (rc == 0);
1772 WINPR_JSON_Delete(json);
1773 return rc;
1774}
1775
1776int tls_verify_certificate(rdpTls* tls, const rdpCertificate* cert, const char* hostname,
1777 UINT16 port)
1778{
1779 int match = 0;
1780 size_t length = 0;
1781 BOOL certificate_status = 0;
1782 char* common_name = nullptr;
1783 size_t common_name_length = 0;
1784 int verification_status = -1;
1785 BOOL hostname_match = FALSE;
1786 rdpCertificateData* certificate_data = nullptr;
1787 BYTE* pemCert = nullptr;
1788 DWORD flags = VERIFY_CERT_FLAG_NONE;
1789
1790 WINPR_ASSERT(tls);
1791
1792 rdpContext* context = tls->context;
1793 WINPR_ASSERT(context);
1794
1795 freerdp* instance = context->instance;
1796 WINPR_ASSERT(instance);
1797
1798 const rdpSettings* settings = context->settings;
1799 WINPR_ASSERT(settings);
1800
1801 if (freerdp_shall_disconnect_context(context))
1802 return -1;
1803
1804 if (!tls_extract_full_pem(cert, &pemCert, &length))
1805 goto end;
1806
1807 /* Check, if we already accepted this key. */
1808 if (is_accepted(tls, cert))
1809 {
1810 verification_status = 1;
1811 goto end;
1812 }
1813
1814 if (is_accepted_fingerprint(cert, settings->CertificateAcceptedFingerprints))
1815 {
1816 verification_status = 1;
1817 goto end;
1818 }
1819
1820 if (tls->isGatewayTransport || is_redirected(tls))
1821 flags |= VERIFY_CERT_FLAG_LEGACY;
1822
1823 if (tls->isGatewayTransport)
1824 flags |= VERIFY_CERT_FLAG_GATEWAY;
1825
1826 if (is_redirected(tls))
1827 flags |= VERIFY_CERT_FLAG_REDIRECT;
1828
1829 /* Certificate management is done by the application */
1830 if (settings->ExternalCertificateManagement)
1831 {
1832 if (instance->VerifyX509Certificate)
1833 verification_status =
1834 instance->VerifyX509Certificate(instance, pemCert, length, hostname, port, flags);
1835 else
1836 WLog_ERR(TAG, "No VerifyX509Certificate callback registered!");
1837
1838 if (verification_status > 0)
1839 {
1840 if (!accept_cert(tls, cert))
1841 goto end;
1842 }
1843 else if (verification_status < 0)
1844 {
1845 WLog_ERR(TAG, "VerifyX509Certificate failed: (length = %" PRIuz ") status: [%d] %s",
1846 length, verification_status, pemCert);
1847 goto end;
1848 }
1849 }
1850 /* ignore certificate verification if user explicitly required it (discouraged) */
1851 else if (freerdp_settings_get_bool(settings, FreeRDP_IgnoreCertificate))
1852 {
1853 WLog_WARN(TAG, "[DANGER] Certificate not checked, /cert:ignore in use.");
1854 WLog_WARN(TAG, "[DANGER] This prevents MITM attacks from being detected!");
1855 WLog_WARN(TAG,
1856 "[DANGER] Avoid using this unless in a secure LAN (=no internet) environment");
1857 verification_status = 1; /* success! */
1858 }
1859 else if (!tls->isGatewayTransport && (settings->AuthenticationLevel == 0))
1860 verification_status = 1; /* success! */
1861 else
1862 {
1863 /* if user explicitly specified a certificate name, use it instead of the hostname */
1864 if (!tls->isGatewayTransport && settings->CertificateName)
1865 hostname = settings->CertificateName;
1866
1867 /* attempt verification using OpenSSL and the ~/.freerdp/certs certificate store */
1868 certificate_status = freerdp_certificate_verify(
1869 cert, freerdp_certificate_store_get_certs_path(tls->certificate_store));
1870 /* verify certificate name match */
1871 certificate_data = freerdp_certificate_data_new(hostname, port, cert);
1872 if (!certificate_data)
1873 goto end;
1874 /* extra common name and alternative names */
1875 common_name = freerdp_certificate_get_common_name(cert, &common_name_length);
1876
1877 const size_t hostlen = strlen(hostname);
1878 if (freerdp_certificate_matches_hostname(cert, hostname, hostlen))
1879 hostname_match = TRUE;
1880
1881 /* if the certificate is valid and the certificate name matches, verification succeeds
1882 */
1883 if (certificate_status && hostname_match)
1884 verification_status = 1; /* success! */
1885
1886 if (!hostname_match)
1887 flags |= VERIFY_CERT_FLAG_MISMATCH;
1888
1889 BOOL allowUserconfig = TRUE;
1890 if (!certificate_status || !hostname_match)
1891 verification_status = tls_config_check_certificate(cert, &allowUserconfig);
1892
1893 /* verification could not succeed with OpenSSL, use known_hosts file and prompt user for
1894 * manual verification */
1895 if (allowUserconfig && (!certificate_status || !hostname_match))
1896 {
1897 DWORD accept_certificate = 0;
1898 size_t pem_length = 0;
1899 char* issuer = freerdp_certificate_get_issuer(cert);
1900 char* subject = freerdp_certificate_get_subject(cert);
1901 char* pem = freerdp_certificate_get_pem(cert, &pem_length);
1902
1903 if (!pem)
1904 goto end;
1905
1906 /* search for matching entry in known_hosts file */
1907 match =
1908 freerdp_certificate_store_contains_data(tls->certificate_store, certificate_data);
1909
1910 if (match == 1)
1911 {
1912 /* no entry was found in known_hosts file, prompt user for manual verification
1913 */
1914 if (!hostname_match)
1915 tls_print_certificate_name_mismatch_error(cert, hostname, port);
1916
1917 {
1918 const char* type = "";
1919 if (freerdp_settings_get_bool(settings, FreeRDP_AutoAcceptCertificate))
1920 type = "tofo (auto-accept)";
1921
1922 if (freerdp_settings_get_bool(settings, FreeRDP_AutoDenyCertificate))
1923 type = "strict (auto-deny)";
1924
1925 if (freerdp_settings_get_bool(settings, FreeRDP_IgnoreCertificate))
1926 type = "ignore (no check)";
1927
1928 char* efp = freerdp_certificate_get_fingerprint(cert);
1929 tls_print_new_certificate_warn(tls->certificate_store, hostname, port, type,
1930 efp);
1931 free(efp);
1932 }
1933
1934#if !defined(WITHOUT_FREERDP_3x_DEPRECATED)
1935 WINPR_PRAGMA_DIAG_PUSH
1936 WINPR_PRAGMA_DIAG_IGNORED_DEPRECATED_DECL
1937#endif
1938
1939 /* Automatically accept certificate on first use */
1940 if (settings->AutoAcceptCertificate)
1941 {
1942 WLog_INFO(TAG, "No certificate stored, automatically accepting.");
1943 accept_certificate = 1;
1944 }
1945 else if (settings->AutoDenyCertificate)
1946 {
1947 WLog_INFO(TAG, "No certificate stored, automatically denying.");
1948 accept_certificate = 0;
1949 }
1950 else if (instance->VerifyX509Certificate)
1951 {
1952 int rc = instance->VerifyX509Certificate(instance, pemCert, pem_length,
1953 hostname, port, flags);
1954
1955 if (rc == 1)
1956 accept_certificate = 1;
1957 else if (rc > 1)
1958 accept_certificate = 2;
1959 else
1960 accept_certificate = 0;
1961 }
1962 else if (instance->VerifyCertificateEx)
1963 {
1964 const BOOL use_pem =
1965 freerdp_settings_get_bool(settings, FreeRDP_CertificateCallbackPreferPEM);
1966 char* fp = nullptr;
1967 DWORD cflags = flags;
1968 if (use_pem)
1969 {
1970 cflags |= VERIFY_CERT_FLAG_FP_IS_PEM;
1971 fp = pem;
1972 }
1973 else
1974 fp = freerdp_certificate_get_fingerprint(cert);
1975 accept_certificate = instance->VerifyCertificateEx(
1976 instance, hostname, port, common_name, subject, issuer, fp, cflags);
1977 if (!use_pem)
1978 free(fp);
1979 }
1980#if !defined(WITHOUT_FREERDP_3x_DEPRECATED)
1981 else if (instance->VerifyCertificate)
1982 {
1983 char* fp = freerdp_certificate_get_fingerprint(cert);
1984
1985 WLog_WARN(TAG, "The VerifyCertificate callback is deprecated, migrate your "
1986 "application to VerifyCertificateEx");
1987 accept_certificate = instance->VerifyCertificate(instance, common_name, subject,
1988 issuer, fp, !hostname_match);
1989 free(fp);
1990 }
1991#endif
1992 }
1993 else if (match == -1)
1994 {
1995 rdpCertificateData* stored_data =
1996 freerdp_certificate_store_load_data(tls->certificate_store, hostname, port);
1997 /* entry was found in known_hosts file, but fingerprint does not match. ask user
1998 * to use it */
1999 {
2000 char* efp = freerdp_certificate_get_fingerprint(cert);
2001 tls_print_certificate_error(tls->certificate_store, stored_data, hostname, port,
2002 efp);
2003 free(efp);
2004 }
2005
2006 if (!stored_data)
2007 WLog_WARN(TAG, "Failed to get certificate entry for %s:%" PRIu16 "", hostname,
2008 port);
2009
2010 if (settings->AutoDenyCertificate)
2011 {
2012 WLog_INFO(TAG, "No certificate stored, automatically denying.");
2013 accept_certificate = 0;
2014 }
2015 else if (instance->VerifyX509Certificate)
2016 {
2017 const int rc =
2018 instance->VerifyX509Certificate(instance, pemCert, pem_length, hostname,
2019 port, flags | VERIFY_CERT_FLAG_CHANGED);
2020
2021 if (rc == 1)
2022 accept_certificate = 1;
2023 else if (rc > 1)
2024 accept_certificate = 2;
2025 else
2026 accept_certificate = 0;
2027 }
2028 else if (instance->VerifyChangedCertificateEx)
2029 {
2030 DWORD cflags = flags | VERIFY_CERT_FLAG_CHANGED;
2031 const char* old_subject = freerdp_certificate_data_get_subject(stored_data);
2032 const char* old_issuer = freerdp_certificate_data_get_issuer(stored_data);
2033 const char* old_fp = freerdp_certificate_data_get_fingerprint(stored_data);
2034 const char* old_pem = freerdp_certificate_data_get_pem(stored_data);
2035 const BOOL fpIsAllocated =
2036 !old_pem ||
2037 !freerdp_settings_get_bool(settings, FreeRDP_CertificateCallbackPreferPEM);
2038 char* fp = nullptr;
2039 if (!fpIsAllocated)
2040 {
2041 cflags |= VERIFY_CERT_FLAG_FP_IS_PEM;
2042 fp = pem;
2043 old_fp = old_pem;
2044 }
2045 else
2046 {
2047 fp = freerdp_certificate_get_fingerprint(cert);
2048 }
2049 accept_certificate = instance->VerifyChangedCertificateEx(
2050 instance, hostname, port, common_name, subject, issuer, fp, old_subject,
2051 old_issuer, old_fp, cflags);
2052 if (fpIsAllocated)
2053 free(fp);
2054 }
2055#if !defined(WITHOUT_FREERDP_3x_DEPRECATED)
2056 else if (instance->VerifyChangedCertificate)
2057 {
2058 char* fp = freerdp_certificate_get_fingerprint(cert);
2059 const char* old_subject = freerdp_certificate_data_get_subject(stored_data);
2060 const char* old_issuer = freerdp_certificate_data_get_issuer(stored_data);
2061 const char* old_fingerprint =
2062 freerdp_certificate_data_get_fingerprint(stored_data);
2063
2064 WLog_WARN(TAG, "The VerifyChangedCertificate callback is deprecated, migrate "
2065 "your application to VerifyChangedCertificateEx");
2066 accept_certificate = instance->VerifyChangedCertificate(
2067 instance, common_name, subject, issuer, fp, old_subject, old_issuer,
2068 old_fingerprint);
2069 free(fp);
2070 }
2071#endif
2072
2073 freerdp_certificate_data_free(stored_data);
2074 }
2075 else if (match == 0)
2076 accept_certificate = 2; /* success! */
2077
2078#if !defined(WITHOUT_FREERDP_3x_DEPRECATED)
2079 WINPR_PRAGMA_DIAG_POP
2080#endif
2081
2082 /* Save certificate or do a simple accept / reject */
2083 switch (accept_certificate)
2084 {
2085 case 1:
2086
2087 /* user accepted certificate, add entry in known_hosts file */
2088 verification_status = freerdp_certificate_store_save_data(
2089 tls->certificate_store, certificate_data)
2090 ? 1
2091 : -1;
2092 break;
2093
2094 case 2:
2095 /* user did accept temporary, do not add to known hosts file */
2096 verification_status = 1;
2097 break;
2098
2099 default:
2100 /* user did not accept, abort and do not add entry in known_hosts file */
2101 verification_status = -1; /* failure! */
2102 break;
2103 }
2104
2105 free(issuer);
2106 free(subject);
2107 free(pem);
2108 }
2109
2110 if (verification_status > 0)
2111 {
2112 if (!accept_cert(tls, cert))
2113 goto end;
2114 }
2115 }
2116
2117end:
2118 freerdp_certificate_data_free(certificate_data);
2119 free(common_name);
2120 free(pemCert);
2121 return verification_status;
2122}
2123
2124void tls_print_new_certificate_warn(rdpCertificateStore* store, const char* hostname, UINT16 port,
2125 const char* type, const char* fingerprint)
2126{
2127 char* path = freerdp_certificate_store_get_cert_path(store, hostname, port);
2128
2129 WLog_ERR(TAG, "The host key for %s:%" PRIu16 " has changed", hostname, port);
2130 WLog_ERR(TAG, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
2131 WLog_ERR(TAG, "@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
2132 WLog_ERR(TAG, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
2133 WLog_ERR(TAG, "IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
2134 WLog_ERR(TAG, "Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
2135 WLog_ERR(TAG, "It is also possible that a host key has just been changed.");
2136 WLog_ERR(TAG, "The fingerprint for the host key sent by the remote host is %s", fingerprint);
2137 WLog_ERR(TAG, "Please contact your system administrator.");
2138 WLog_ERR(TAG, "Add correct host key in %s to get rid of this message.", path);
2139 WLog_ERR(TAG, "Host key for %s has changed and you have requested %s checking.", hostname,
2140 type);
2141 WLog_ERR(TAG, "Host key verification failed.");
2142
2143 free(path);
2144}
2145
2146void tls_print_certificate_error(rdpCertificateStore* store,
2147 WINPR_ATTR_UNUSED rdpCertificateData* stored_data,
2148 const char* hostname, UINT16 port, const char* fingerprint)
2149{
2150 char* path = freerdp_certificate_store_get_cert_path(store, hostname, port);
2151
2152 WLog_ERR(TAG, "New host key for %s:%" PRIu16, hostname, port);
2153 WLog_ERR(TAG, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
2154 WLog_ERR(TAG, "@ WARNING: NEW HOST IDENTIFICATION! @");
2155 WLog_ERR(TAG, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
2156
2157 WLog_ERR(TAG, "The fingerprint for the host key sent by the remote host is %s", fingerprint);
2158 WLog_ERR(TAG, "Please contact your system administrator.");
2159 WLog_ERR(TAG, "Add correct host key in %s to get rid of this message.", path);
2160
2161 free(path);
2162}
2163
2164void tls_print_certificate_name_mismatch_error(const rdpCertificate* cert, const char* hostname,
2165 UINT16 port)
2166{
2167 WINPR_ASSERT(nullptr != hostname);
2168 WINPR_ASSERT(cert);
2169
2170 size_t common_name_length = 0;
2171 char* common_name = freerdp_certificate_get_common_name(cert, &common_name_length);
2172
2173 size_t dnscount = 0;
2174 size_t* dnslengths = nullptr;
2175 char** dnsnames = freerdp_certificate_get_dns_names(cert, &dnscount, &dnslengths);
2176
2177 size_t ipcount = 0;
2178 size_t* iplengths = nullptr;
2179 char** ipnames = freerdp_certificate_get_ip_names(cert, &ipcount, &iplengths);
2180
2181 size_t count = dnscount;
2182 char** names = dnsnames;
2183 const BOOL isIP = utils_is_valid_ip(hostname);
2184 if (isIP)
2185 {
2186 count = ipcount;
2187 names = ipnames;
2188 }
2189
2190 WLog_ERR(TAG, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
2191 WLog_ERR(TAG, "@ WARNING: CERTIFICATE NAME MISMATCH! @");
2192 WLog_ERR(TAG, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
2193 WLog_ERR(TAG, "The hostname used for this connection (%s:%" PRIu16 ") ", hostname, port);
2194 WLog_ERR(TAG, "does not match %s given in the certificate:",
2195 count < 1 ? "the name" : "any of the names");
2196 WLog_ERR(TAG, "Common Name (CN):");
2197 WLog_ERR(TAG, "\t%s", common_name ? common_name : "no CN found in certificate");
2198
2199 if (count > 0)
2200 {
2201 WINPR_ASSERT(nullptr != names);
2202 WLog_ERR(TAG, "Alternative names:");
2203
2204 for (size_t index = 0; index < count; index++)
2205 {
2206 WINPR_ASSERT(names[index]);
2207 WLog_ERR(TAG, "\t %s", names[index]);
2208 }
2209 }
2210
2211 WLog_ERR(TAG, "A valid certificate for the wrong name should NOT be trusted!");
2212
2213 freerdp_certificate_free_dns_names(dnscount, dnslengths, dnsnames);
2214 freerdp_certificate_free_ip_names(ipcount, iplengths, ipnames);
2215 winpr_znfree(common_name, common_name_length);
2216}
2217
2218rdpTls* freerdp_tls_new(rdpContext* context)
2219{
2220 rdpTls* tls = nullptr;
2221 tls = (rdpTls*)calloc(1, sizeof(rdpTls));
2222
2223 if (!tls)
2224 return nullptr;
2225
2226 tls->context = context;
2227
2228 if (!freerdp_settings_get_bool(tls->context->settings, FreeRDP_ServerMode))
2229 {
2230 tls->certificate_store = freerdp_certificate_store_new(tls->context->settings);
2231
2232 if (!tls->certificate_store)
2233 goto out_free;
2234 }
2235
2236 tls->alertLevel = TLS_ALERT_LEVEL_WARNING;
2237 tls->alertDescription = TLS_ALERT_DESCRIPTION_CLOSE_NOTIFY;
2238 return tls;
2239out_free:
2240 free(tls);
2241 return nullptr;
2242}
2243
2244void freerdp_tls_free(rdpTls* tls)
2245{
2246 if (!tls)
2247 return;
2248
2249 tls_reset(tls);
2250
2251 if (tls->certificate_store)
2252 {
2253 freerdp_certificate_store_free(tls->certificate_store);
2254 tls->certificate_store = nullptr;
2255 }
2256
2257 free(tls);
2258}
WINPR_ATTR_NODISCARD WINPR_API BOOL WINPR_JSON_IsBool(const WINPR_JSON *item)
Check if JSON item is of type BOOL.
Definition c-json.c:167
WINPR_ATTR_NODISCARD WINPR_API size_t WINPR_JSON_GetArraySize(const WINPR_JSON *array)
Get the number of arrayitems from an array.
Definition c-json.c:114
WINPR_ATTR_NODISCARD WINPR_API BOOL WINPR_JSON_IsTrue(const WINPR_JSON *item)
Check if JSON item is BOOL value True.
Definition c-json.c:162
WINPR_ATTR_NODISCARD WINPR_API WINPR_JSON * WINPR_JSON_GetObjectItemCaseSensitive(const WINPR_JSON *object, const char *string)
Same as WINPR_JSON_GetObjectItem but with case sensitive matching.
Definition c-json.c:127
WINPR_ATTR_NODISCARD WINPR_API BOOL WINPR_JSON_IsString(const WINPR_JSON *item)
Check if JSON item is of type String.
Definition c-json.c:182
WINPR_ATTR_NODISCARD WINPR_API WINPR_JSON * WINPR_JSON_GetArrayItem(const WINPR_JSON *array, size_t index)
Return a pointer to an item in the array.
Definition c-json.c:108
WINPR_ATTR_NODISCARD WINPR_API BOOL WINPR_JSON_IsArray(const WINPR_JSON *item)
Check if JSON item is of type Array.
Definition c-json.c:187
WINPR_ATTR_NODISCARD WINPR_API BOOL WINPR_JSON_IsObject(const WINPR_JSON *item)
Check if JSON item is of type Object.
Definition c-json.c:192
WINPR_API void WINPR_JSON_Delete(WINPR_JSON *item)
Delete a WinPR JSON wrapper object.
Definition c-json.c:103
WINPR_ATTR_NODISCARD WINPR_API const char * WINPR_JSON_GetStringValue(WINPR_JSON *item)
Return the String value of a JSON item.
Definition c-json.c:142
WINPR_ATTR_NODISCARD FREERDP_API const void * freerdp_settings_get_pointer(const rdpSettings *settings, FreeRDP_Settings_Keys_Pointer id)
Returns a immutable pointer settings value.
WINPR_ATTR_NODISCARD FREERDP_API const char * freerdp_settings_get_string(const rdpSettings *settings, FreeRDP_Settings_Keys_String id)
Returns a immutable string settings value.
WINPR_ATTR_NODISCARD FREERDP_API BOOL freerdp_settings_set_string_len(rdpSettings *settings, FreeRDP_Settings_Keys_String id, const char *val, size_t len)
Sets a string settings value. The val is copied.
WINPR_ATTR_NODISCARD FREERDP_API void * freerdp_settings_get_pointer_writable(rdpSettings *settings, FreeRDP_Settings_Keys_Pointer id)
Returns a mutable pointer settings value.
WINPR_ATTR_NODISCARD FREERDP_API UINT16 freerdp_settings_get_uint16(const rdpSettings *settings, FreeRDP_Settings_Keys_UInt16 id)
Returns a UINT16 settings value.
WINPR_ATTR_NODISCARD FREERDP_API BOOL freerdp_settings_set_uint32(rdpSettings *settings, FreeRDP_Settings_Keys_UInt32 id, UINT32 val)
Sets a UINT32 settings value.
WINPR_ATTR_NODISCARD FREERDP_API UINT32 freerdp_settings_get_uint32(const rdpSettings *settings, FreeRDP_Settings_Keys_UInt32 id)
Returns a UINT32 settings value.
WINPR_ATTR_NODISCARD FREERDP_API BOOL freerdp_settings_set_string(rdpSettings *settings, FreeRDP_Settings_Keys_String id, const char *val)
Sets a string settings value. The param is copied.
WINPR_ATTR_NODISCARD FREERDP_API BOOL freerdp_settings_get_bool(const rdpSettings *settings, FreeRDP_Settings_Keys_Bool id)
Returns a boolean settings value.