-
Notifications
You must be signed in to change notification settings - Fork 6.5k
/
sockets_tls.c
3889 lines (3151 loc) · 85.2 KB
/
sockets_tls.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Copyright (c) 2018 Intel Corporation
* Copyright (c) 2018 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdbool.h>
#include <zephyr/posix/fcntl.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(net_sock_tls, CONFIG_NET_SOCKETS_LOG_LEVEL);
#include <zephyr/init.h>
#include <zephyr/sys/util.h>
#include <zephyr/net/socket.h>
#include <zephyr/random/random.h>
#include <zephyr/internal/syscall_handler.h>
#include <zephyr/sys/fdtable.h>
/* TODO: Remove all direct access to private fields.
* According with Mbed TLS migration guide:
*
* Direct access to fields of structures
* (`struct` types) declared in public headers is no longer
* supported. In Mbed TLS 3, the layout of structures is not
* considered part of the stable API, and minor versions (3.1, 3.2,
* etc.) may add, remove, rename, reorder or change the type of
* structure fields.
*/
#if !defined(MBEDTLS_ALLOW_PRIVATE_ACCESS)
#define MBEDTLS_ALLOW_PRIVATE_ACCESS
#endif
#if defined(CONFIG_MBEDTLS)
#if !defined(CONFIG_MBEDTLS_CFG_FILE)
#include "mbedtls/config.h"
#else
#include CONFIG_MBEDTLS_CFG_FILE
#endif /* CONFIG_MBEDTLS_CFG_FILE */
#include <mbedtls/net_sockets.h>
#include <mbedtls/x509.h>
#include <mbedtls/x509_crt.h>
#include <mbedtls/ssl.h>
#include <mbedtls/ssl_cookie.h>
#include <mbedtls/error.h>
#include <mbedtls/platform.h>
#include <mbedtls/ssl_cache.h>
#endif /* CONFIG_MBEDTLS */
#include "sockets_internal.h"
#include "tls_internal.h"
#if defined(CONFIG_MBEDTLS_DEBUG)
#include <zephyr_mbedtls_priv.h>
#endif
#if defined(CONFIG_NET_SOCKETS_TLS_MAX_APP_PROTOCOLS)
#define ALPN_MAX_PROTOCOLS (CONFIG_NET_SOCKETS_TLS_MAX_APP_PROTOCOLS + 1)
#else
#define ALPN_MAX_PROTOCOLS 0
#endif /* CONFIG_NET_SOCKETS_TLS_MAX_APP_PROTOCOLS */
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
#define DTLS_SENDMSG_BUF_SIZE (CONFIG_NET_SOCKETS_DTLS_SENDMSG_BUF_SIZE)
#else
#define DTLS_SENDMSG_BUF_SIZE 0
#endif /* CONFIG_NET_SOCKETS_ENABLE_DTLS */
static const struct socket_op_vtable tls_sock_fd_op_vtable;
#ifndef MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED
#define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE
#endif
/** A list of secure tags that TLS context should use. */
struct sec_tag_list {
/** An array of secure tags referencing TLS credentials. */
sec_tag_t sec_tags[CONFIG_NET_SOCKETS_TLS_MAX_CREDENTIALS];
/** Number of configured secure tags. */
int sec_tag_count;
};
/** Timer context for DTLS. */
struct dtls_timing_context {
/** Current time, stored during timer set. */
uint32_t snapshot;
/** Intermediate delay value. For details, refer to mbedTLS API
* documentation (mbedtls_ssl_set_timer_t).
*/
uint32_t int_ms;
/** Final delay value. For details, refer to mbedTLS API documentation
* (mbedtls_ssl_set_timer_t).
*/
uint32_t fin_ms;
};
/** TLS peer address/session ID mapping. */
struct tls_session_cache {
/** Creation time. */
int64_t timestamp;
/** Peer address. */
struct sockaddr peer_addr;
/** Session buffer. */
uint8_t *session;
/** Session length. */
size_t session_len;
};
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
struct tls_dtls_cid {
bool enabled;
unsigned char cid[MAX(MBEDTLS_SSL_CID_OUT_LEN_MAX,
MBEDTLS_SSL_CID_IN_LEN_MAX)];
size_t cid_len;
};
#endif
/** TLS context information. */
__net_socket struct tls_context {
/** Underlying TCP/UDP socket. */
int sock;
/** Information whether TLS context is used. */
bool is_used : 1;
/** Information whether TLS context was initialized. */
bool is_initialized : 1;
/** Information whether underlying socket is listening. */
bool is_listening : 1;
/** Information whether TLS handshake is currently in progress. */
bool handshake_in_progress : 1;
/** Session ended at the TLS/DTLS level. */
bool session_closed : 1;
/** Socket type. */
enum net_sock_type type;
/** Secure protocol version running on TLS context. */
enum net_ip_protocol_secure tls_version;
/** Socket flags passed to a socket call. */
int flags;
/* Indicates whether socket is in error state at TLS/DTLS level. */
int error;
/** Information whether TLS handshake is complete or not. */
struct k_sem tls_established;
/* TLS socket mutex lock. */
struct k_mutex *lock;
/** TLS specific option values. */
struct {
/** Select which credentials to use with TLS. */
struct sec_tag_list sec_tag_list;
/** 0-terminated list of allowed ciphersuites (mbedTLS format).
*/
int ciphersuites[CONFIG_NET_SOCKETS_TLS_MAX_CIPHERSUITES + 1];
/** Information if hostname was explicitly set on a socket. */
bool is_hostname_set;
/** Peer verification level. */
int8_t verify_level;
/** Indicating on whether DER certificates should not be copied
* to the heap.
*/
int8_t cert_nocopy;
/** DTLS role, client by default. */
int8_t role;
/** NULL-terminated list of allowed application layer
* protocols.
*/
const char *alpn_list[ALPN_MAX_PROTOCOLS];
/** Session cache enabled on a socket. */
bool cache_enabled;
/** Socket TX timeout */
k_timeout_t timeout_tx;
/** Socket RX timeout */
k_timeout_t timeout_rx;
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
/* DTLS handshake timeout */
uint32_t dtls_handshake_timeout_min;
uint32_t dtls_handshake_timeout_max;
struct tls_dtls_cid dtls_cid;
bool dtls_handshake_on_connect;
#endif /* CONFIG_NET_SOCKETS_ENABLE_DTLS */
} options;
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
/** Context information for DTLS timing. */
struct dtls_timing_context dtls_timing;
/** mbedTLS cookie context for DTLS */
mbedtls_ssl_cookie_ctx cookie;
/** DTLS peer address. */
struct sockaddr dtls_peer_addr;
/** DTLS peer address length. */
socklen_t dtls_peer_addrlen;
#endif /* CONFIG_NET_SOCKETS_ENABLE_DTLS */
#if defined(CONFIG_MBEDTLS)
/** mbedTLS context. */
mbedtls_ssl_context ssl;
/** mbedTLS configuration. */
mbedtls_ssl_config config;
#if defined(MBEDTLS_X509_CRT_PARSE_C)
/** mbedTLS structure for CA chain. */
mbedtls_x509_crt ca_chain;
/** mbedTLS structure for own certificate. */
mbedtls_x509_crt own_cert;
/** mbedTLS structure for own private key. */
mbedtls_pk_context priv_key;
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#endif /* CONFIG_MBEDTLS */
};
/* A global pool of TLS contexts. */
static struct tls_context tls_contexts[CONFIG_NET_SOCKETS_TLS_MAX_CONTEXTS];
static struct tls_session_cache client_cache[CONFIG_NET_SOCKETS_TLS_MAX_CLIENT_SESSION_COUNT];
#if defined(MBEDTLS_SSL_CACHE_C)
static mbedtls_ssl_cache_context server_cache;
#endif
/* A mutex for protecting TLS context allocation. */
static struct k_mutex context_lock;
/* Arbitrary delay value to wait if mbedTLS reports it cannot proceed for
* reasons other than TX/RX block.
*/
#define TLS_WAIT_MS 100
static void tls_session_cache_reset(void)
{
for (int i = 0; i < ARRAY_SIZE(client_cache); i++) {
if (client_cache[i].session != NULL) {
mbedtls_free(client_cache[i].session);
}
}
(void)memset(client_cache, 0, sizeof(client_cache));
}
bool net_socket_is_tls(void *obj)
{
return PART_OF_ARRAY(tls_contexts, (struct tls_context *)obj);
}
static int tls_ctr_drbg_random(void *ctx, unsigned char *buf, size_t len)
{
ARG_UNUSED(ctx);
#if defined(CONFIG_CSPRNG_ENABLED)
return sys_csrand_get(buf, len);
#else
sys_rand_get(buf, len);
return 0;
#endif
}
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
/* mbedTLS-defined function for setting timer. */
static void dtls_timing_set_delay(void *data, uint32_t int_ms, uint32_t fin_ms)
{
struct dtls_timing_context *ctx = data;
ctx->int_ms = int_ms;
ctx->fin_ms = fin_ms;
if (fin_ms != 0U) {
ctx->snapshot = k_uptime_get_32();
}
}
/* mbedTLS-defined function for getting timer status.
* The return values are specified by mbedTLS. The callback must return:
* -1 if cancelled (fin_ms == 0),
* 0 if none of the delays have passed,
* 1 if only the intermediate delay has passed,
* 2 if the final delay has passed.
*/
static int dtls_timing_get_delay(void *data)
{
struct dtls_timing_context *timing = data;
unsigned long elapsed_ms;
NET_ASSERT(timing);
if (timing->fin_ms == 0U) {
return -1;
}
elapsed_ms = k_uptime_get_32() - timing->snapshot;
if (elapsed_ms >= timing->fin_ms) {
return 2;
}
if (elapsed_ms >= timing->int_ms) {
return 1;
}
return 0;
}
static int dtls_get_remaining_timeout(struct tls_context *ctx)
{
struct dtls_timing_context *timing = &ctx->dtls_timing;
uint32_t elapsed_ms;
elapsed_ms = k_uptime_get_32() - timing->snapshot;
if (timing->fin_ms == 0U) {
return SYS_FOREVER_MS;
}
if (elapsed_ms >= timing->fin_ms) {
return 0;
}
return timing->fin_ms - elapsed_ms;
}
#endif /* CONFIG_NET_SOCKETS_ENABLE_DTLS */
/* Initialize TLS internals. */
static int tls_init(void)
{
#if !defined(CONFIG_ENTROPY_HAS_DRIVER)
NET_WARN("No entropy device on the system, "
"TLS communication is insecure!");
#endif
(void)memset(tls_contexts, 0, sizeof(tls_contexts));
(void)memset(client_cache, 0, sizeof(client_cache));
k_mutex_init(&context_lock);
#if defined(MBEDTLS_SSL_CACHE_C)
mbedtls_ssl_cache_init(&server_cache);
#endif
return 0;
}
SYS_INIT(tls_init, APPLICATION, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
static inline bool is_handshake_complete(struct tls_context *ctx)
{
return k_sem_count_get(&ctx->tls_established) != 0;
}
/*
* Copied from include/mbedtls/ssl_internal.h
*
* Maximum length we can advertise as our max content length for
* RFC 6066 max_fragment_length extension negotiation purposes
* (the lesser of both sizes, if they are unequal.)
*/
#define MBEDTLS_TLS_EXT_ADV_CONTENT_LEN ( \
(MBEDTLS_SSL_IN_CONTENT_LEN > MBEDTLS_SSL_OUT_CONTENT_LEN) \
? (MBEDTLS_SSL_OUT_CONTENT_LEN) \
: (MBEDTLS_SSL_IN_CONTENT_LEN) \
)
#if defined(CONFIG_NET_SOCKETS_TLS_SET_MAX_FRAGMENT_LENGTH) && \
defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) && \
(MBEDTLS_TLS_EXT_ADV_CONTENT_LEN < 16384)
BUILD_ASSERT(MBEDTLS_TLS_EXT_ADV_CONTENT_LEN >= 512,
"Too small content length!");
static inline unsigned char tls_mfl_code_from_content_len(size_t len)
{
if (len >= 4096) {
return MBEDTLS_SSL_MAX_FRAG_LEN_4096;
} else if (len >= 2048) {
return MBEDTLS_SSL_MAX_FRAG_LEN_2048;
} else if (len >= 1024) {
return MBEDTLS_SSL_MAX_FRAG_LEN_1024;
} else if (len >= 512) {
return MBEDTLS_SSL_MAX_FRAG_LEN_512;
} else {
return MBEDTLS_SSL_MAX_FRAG_LEN_INVALID;
}
}
static inline void tls_set_max_frag_len(mbedtls_ssl_config *config, enum net_sock_type type)
{
unsigned char mfl_code;
size_t len = MBEDTLS_TLS_EXT_ADV_CONTENT_LEN;
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
if (type == SOCK_DGRAM && len > CONFIG_NET_SOCKETS_DTLS_MAX_FRAGMENT_LENGTH) {
len = CONFIG_NET_SOCKETS_DTLS_MAX_FRAGMENT_LENGTH;
}
#endif
mfl_code = tls_mfl_code_from_content_len(len);
mbedtls_ssl_conf_max_frag_len(config, mfl_code);
}
#else
static inline void tls_set_max_frag_len(mbedtls_ssl_config *config, enum net_sock_type type) {}
#endif
/* Allocate TLS context. */
static struct tls_context *tls_alloc(void)
{
int i;
struct tls_context *tls = NULL;
k_mutex_lock(&context_lock, K_FOREVER);
for (i = 0; i < ARRAY_SIZE(tls_contexts); i++) {
if (!tls_contexts[i].is_used) {
tls = &tls_contexts[i];
(void)memset(tls, 0, sizeof(*tls));
tls->is_used = true;
tls->options.verify_level = -1;
tls->options.timeout_tx = K_FOREVER;
tls->options.timeout_rx = K_FOREVER;
tls->sock = -1;
NET_DBG("Allocated TLS context, %p", tls);
break;
}
}
k_mutex_unlock(&context_lock);
if (tls) {
k_sem_init(&tls->tls_established, 0, 1);
mbedtls_ssl_init(&tls->ssl);
mbedtls_ssl_config_init(&tls->config);
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
mbedtls_ssl_cookie_init(&tls->cookie);
tls->options.dtls_handshake_timeout_min =
MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN;
tls->options.dtls_handshake_timeout_max =
MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX;
tls->options.dtls_cid.cid_len = 0;
tls->options.dtls_cid.enabled = false;
tls->options.dtls_handshake_on_connect = true;
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C)
mbedtls_x509_crt_init(&tls->ca_chain);
mbedtls_x509_crt_init(&tls->own_cert);
mbedtls_pk_init(&tls->priv_key);
#endif
#if defined(CONFIG_MBEDTLS_DEBUG)
mbedtls_ssl_conf_dbg(&tls->config, zephyr_mbedtls_debug, NULL);
#endif
} else {
NET_WARN("Failed to allocate TLS context");
}
return tls;
}
/* Allocate new TLS context and copy the content from the source context. */
static struct tls_context *tls_clone(struct tls_context *source_tls)
{
struct tls_context *target_tls;
target_tls = tls_alloc();
if (!target_tls) {
return NULL;
}
target_tls->tls_version = source_tls->tls_version;
target_tls->type = source_tls->type;
memcpy(&target_tls->options, &source_tls->options,
sizeof(target_tls->options));
#if defined(MBEDTLS_X509_CRT_PARSE_C)
if (target_tls->options.is_hostname_set) {
mbedtls_ssl_set_hostname(&target_tls->ssl,
source_tls->ssl.hostname);
}
#endif
return target_tls;
}
/* Release TLS context. */
static int tls_release(struct tls_context *tls)
{
if (!PART_OF_ARRAY(tls_contexts, tls)) {
NET_ERR("Invalid TLS context");
return -EBADF;
}
if (!tls->is_used) {
NET_ERR("Deallocating unused TLS context");
return -EBADF;
}
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
mbedtls_ssl_cookie_free(&tls->cookie);
#endif
mbedtls_ssl_config_free(&tls->config);
mbedtls_ssl_free(&tls->ssl);
#if defined(MBEDTLS_X509_CRT_PARSE_C)
mbedtls_x509_crt_free(&tls->ca_chain);
mbedtls_x509_crt_free(&tls->own_cert);
mbedtls_pk_free(&tls->priv_key);
#endif
tls->is_used = false;
return 0;
}
static bool peer_addr_cmp(const struct sockaddr *addr,
const struct sockaddr *peer_addr)
{
if (addr->sa_family != peer_addr->sa_family) {
return false;
}
if (IS_ENABLED(CONFIG_NET_IPV6) && peer_addr->sa_family == AF_INET6) {
struct sockaddr_in6 *addr1 = net_sin6(peer_addr);
struct sockaddr_in6 *addr2 = net_sin6(addr);
return (addr1->sin6_port == addr2->sin6_port) &&
net_ipv6_addr_cmp(&addr1->sin6_addr, &addr2->sin6_addr);
} else if (IS_ENABLED(CONFIG_NET_IPV4) && peer_addr->sa_family == AF_INET) {
struct sockaddr_in *addr1 = net_sin(peer_addr);
struct sockaddr_in *addr2 = net_sin(addr);
return (addr1->sin_port == addr2->sin_port) &&
net_ipv4_addr_cmp(&addr1->sin_addr, &addr2->sin_addr);
}
return false;
}
static int tls_session_save(const struct sockaddr *peer_addr,
mbedtls_ssl_session *session)
{
struct tls_session_cache *entry = NULL;
size_t session_len;
int ret;
for (int i = 0; i < ARRAY_SIZE(client_cache); i++) {
if (client_cache[i].session == NULL) {
/* New entry. */
if (entry == NULL || entry->session != NULL) {
entry = &client_cache[i];
}
} else {
if (peer_addr_cmp(&client_cache[i].peer_addr, peer_addr)) {
/* Reuse old entry for given address. */
entry = &client_cache[i];
break;
}
/* Remember the oldest entry and reuse if needed. */
if (entry == NULL ||
(entry->session != NULL &&
entry->timestamp < client_cache[i].timestamp)) {
entry = &client_cache[i];
}
}
}
/* Allocate session and save */
if (entry->session != NULL) {
mbedtls_free(entry->session);
entry->session = NULL;
}
(void)mbedtls_ssl_session_save(session, NULL, 0, &session_len);
entry->session = mbedtls_calloc(1, session_len);
if (entry->session == NULL) {
NET_ERR("Failed to allocate session buffer.");
return -ENOMEM;
}
ret = mbedtls_ssl_session_save(session, entry->session, session_len,
&session_len);
if (ret < 0) {
NET_ERR("Failed to serialize session, err: -0x%x.", -ret);
mbedtls_free(entry->session);
entry->session = NULL;
return -ENOMEM;
}
entry->session_len = session_len;
entry->timestamp = k_uptime_get();
memcpy(&entry->peer_addr, peer_addr, sizeof(*peer_addr));
return 0;
}
static int tls_session_get(const struct sockaddr *peer_addr,
mbedtls_ssl_session *session)
{
struct tls_session_cache *entry = NULL;
int ret;
for (int i = 0; i < ARRAY_SIZE(client_cache); i++) {
if (client_cache[i].session != NULL &&
peer_addr_cmp(&client_cache[i].peer_addr, peer_addr)) {
entry = &client_cache[i];
break;
}
}
if (entry == NULL) {
return -ENOENT;
}
ret = mbedtls_ssl_session_load(session, entry->session,
entry->session_len);
if (ret < 0) {
/* Discard corrupted session data. */
mbedtls_free(entry->session);
entry->session = NULL;
NET_ERR("Failed to load TLS session %d", ret);
return -EIO;
}
return 0;
}
static void tls_session_store(struct tls_context *context,
const struct sockaddr *addr,
socklen_t addrlen)
{
mbedtls_ssl_session session;
struct sockaddr peer_addr = { 0 };
int ret;
if (!context->options.cache_enabled) {
return;
}
memcpy(&peer_addr, addr, addrlen);
mbedtls_ssl_session_init(&session);
ret = mbedtls_ssl_get_session(&context->ssl, &session);
if (ret < 0) {
NET_ERR("Failed to obtain session for %p", context);
goto exit;
}
ret = tls_session_save(&peer_addr, &session);
if (ret < 0) {
NET_ERR("Failed to save session for %p", context);
}
exit:
mbedtls_ssl_session_free(&session);
}
static void tls_session_restore(struct tls_context *context,
const struct sockaddr *addr,
socklen_t addrlen)
{
mbedtls_ssl_session session;
struct sockaddr peer_addr = { 0 };
int ret;
if (!context->options.cache_enabled) {
return;
}
memcpy(&peer_addr, addr, addrlen);
mbedtls_ssl_session_init(&session);
ret = tls_session_get(&peer_addr, &session);
if (ret < 0) {
NET_DBG("Session not found for %p", context);
goto exit;
}
ret = mbedtls_ssl_set_session(&context->ssl, &session);
if (ret < 0) {
NET_ERR("Failed to set session for %p", context);
}
exit:
mbedtls_ssl_session_free(&session);
}
static void tls_session_purge(void)
{
tls_session_cache_reset();
#if defined(MBEDTLS_SSL_CACHE_C)
mbedtls_ssl_cache_free(&server_cache);
mbedtls_ssl_cache_init(&server_cache);
#endif
}
static inline int time_left(uint32_t start, uint32_t timeout)
{
uint32_t elapsed = k_uptime_get_32() - start;
return timeout - elapsed;
}
static int wait(int sock, int timeout, int event)
{
struct zsock_pollfd fds = {
.fd = sock,
.events = event,
};
int ret;
ret = zsock_poll(&fds, 1, timeout);
if (ret < 0) {
return ret;
}
if (ret == 1) {
if (fds.revents & ZSOCK_POLLNVAL) {
return -EBADF;
}
if (fds.revents & ZSOCK_POLLERR) {
int optval;
socklen_t optlen = sizeof(optval);
if (zsock_getsockopt(fds.fd, SOL_SOCKET, SO_ERROR,
&optval, &optlen) == 0) {
NET_ERR("TLS underlying socket poll error %d",
-optval);
return -optval;
}
return -EIO;
}
}
return 0;
}
static int wait_for_reason(int sock, int timeout, int reason)
{
if (reason == MBEDTLS_ERR_SSL_WANT_READ) {
return wait(sock, timeout, ZSOCK_POLLIN);
}
if (reason == MBEDTLS_ERR_SSL_WANT_WRITE) {
return wait(sock, timeout, ZSOCK_POLLOUT);
}
/* Any other reason - no way to monitor, just wait for some time. */
k_msleep(TLS_WAIT_MS);
return 0;
}
static bool is_blocking(int sock, int flags)
{
int sock_flags = zsock_fcntl(sock, F_GETFL, 0);
if (sock_flags == -1) {
return false;
}
return !((flags & ZSOCK_MSG_DONTWAIT) || (sock_flags & O_NONBLOCK));
}
static int timeout_to_ms(k_timeout_t *timeout)
{
if (K_TIMEOUT_EQ(*timeout, K_NO_WAIT)) {
return 0;
} else if (K_TIMEOUT_EQ(*timeout, K_FOREVER)) {
return SYS_FOREVER_MS;
} else {
return k_ticks_to_ms_floor32(timeout->ticks);
}
}
static void ctx_set_lock(struct tls_context *ctx, struct k_mutex *lock)
{
ctx->lock = lock;
}
#if defined(CONFIG_NET_SOCKETS_ENABLE_DTLS)
static bool dtls_is_peer_addr_valid(struct tls_context *context,
const struct sockaddr *peer_addr,
socklen_t addrlen)
{
if (context->dtls_peer_addrlen != addrlen) {
return false;
}
return peer_addr_cmp(&context->dtls_peer_addr, peer_addr);
}
static void dtls_peer_address_set(struct tls_context *context,
const struct sockaddr *peer_addr,
socklen_t addrlen)
{
if (addrlen <= sizeof(context->dtls_peer_addr)) {
memcpy(&context->dtls_peer_addr, peer_addr, addrlen);
context->dtls_peer_addrlen = addrlen;
}
}
static void dtls_peer_address_get(struct tls_context *context,
struct sockaddr *peer_addr,
socklen_t *addrlen)
{
socklen_t len = MIN(context->dtls_peer_addrlen, *addrlen);
memcpy(peer_addr, &context->dtls_peer_addr, len);
*addrlen = len;
}
static int dtls_tx(void *ctx, const unsigned char *buf, size_t len)
{
struct tls_context *tls_ctx = ctx;
ssize_t sent;
sent = zsock_sendto(tls_ctx->sock, buf, len, ZSOCK_MSG_DONTWAIT,
&tls_ctx->dtls_peer_addr,
tls_ctx->dtls_peer_addrlen);
if (sent < 0) {
if (errno == EAGAIN) {
return MBEDTLS_ERR_SSL_WANT_WRITE;
}
return MBEDTLS_ERR_NET_SEND_FAILED;
}
return sent;
}
static int dtls_rx(void *ctx, unsigned char *buf, size_t len)
{
struct tls_context *tls_ctx = ctx;
socklen_t addrlen = sizeof(struct sockaddr);
struct sockaddr addr;
int err;
ssize_t received;
received = zsock_recvfrom(tls_ctx->sock, buf, len,
ZSOCK_MSG_DONTWAIT, &addr, &addrlen);
if (received < 0) {
if (errno == EAGAIN) {
return MBEDTLS_ERR_SSL_WANT_READ;
}
return MBEDTLS_ERR_NET_RECV_FAILED;
}
if (tls_ctx->dtls_peer_addrlen == 0) {
/* Only allow to store peer address for DTLS servers. */
if (tls_ctx->options.role == MBEDTLS_SSL_IS_SERVER) {
dtls_peer_address_set(tls_ctx, &addr, addrlen);
err = mbedtls_ssl_set_client_transport_id(
&tls_ctx->ssl,
(const unsigned char *)&addr, addrlen);
if (err < 0) {
return err;
}
} else {
/* For clients it's incorrect to receive when
* no peer has been set up.
*/
return MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED;
}
} else if (!dtls_is_peer_addr_valid(tls_ctx, &addr, addrlen)) {
return MBEDTLS_ERR_SSL_WANT_READ;
}
return received;
}
#endif /* CONFIG_NET_SOCKETS_ENABLE_DTLS */
static int tls_tx(void *ctx, const unsigned char *buf, size_t len)
{
struct tls_context *tls_ctx = ctx;
ssize_t sent;
sent = zsock_sendto(tls_ctx->sock, buf, len,
ZSOCK_MSG_DONTWAIT, NULL, 0);
if (sent < 0) {
if (errno == EAGAIN) {
return MBEDTLS_ERR_SSL_WANT_WRITE;
}
return MBEDTLS_ERR_NET_SEND_FAILED;
}
return sent;
}
static int tls_rx(void *ctx, unsigned char *buf, size_t len)
{
struct tls_context *tls_ctx = ctx;
ssize_t received;
received = zsock_recvfrom(tls_ctx->sock, buf, len,
ZSOCK_MSG_DONTWAIT, NULL, 0);
if (received < 0) {
if (errno == EAGAIN) {
return MBEDTLS_ERR_SSL_WANT_READ;
}
return MBEDTLS_ERR_NET_RECV_FAILED;
}
return received;
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
static bool crt_is_pem(const unsigned char *buf, size_t buflen)
{
return (buflen != 0 && buf[buflen - 1] == '\0' &&
strstr((const char *)buf, "-----BEGIN CERTIFICATE-----") != NULL);
}
#endif
static int tls_add_ca_certificate(struct tls_context *tls,
struct tls_credential *ca_cert)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
int err;
if (tls->options.cert_nocopy == TLS_CERT_NOCOPY_NONE ||
crt_is_pem(ca_cert->buf, ca_cert->len)) {
err = mbedtls_x509_crt_parse(&tls->ca_chain, ca_cert->buf,
ca_cert->len);
} else {
err = mbedtls_x509_crt_parse_der_nocopy(&tls->ca_chain,
ca_cert->buf,
ca_cert->len);
}
if (err != 0) {
NET_ERR("Failed to parse CA certificate, err: -0x%x", -err);
return -EINVAL;
}
return 0;
#endif /* MBEDTLS_X509_CRT_PARSE_C */
return -ENOTSUP;
}
static void tls_set_ca_chain(struct tls_context *tls)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
mbedtls_ssl_conf_ca_chain(&tls->config, &tls->ca_chain, NULL);
mbedtls_ssl_conf_cert_profile(&tls->config,
&mbedtls_x509_crt_profile_default);
#endif /* MBEDTLS_X509_CRT_PARSE_C */
}
static int tls_add_own_cert(struct tls_context *tls,
struct tls_credential *own_cert)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
int err;