/
openssl.c
2163 lines (1860 loc) · 54.4 KB
/
openssl.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
/*
* OpenConnect (SSL + DTLS) VPN client
*
* Copyright © 2008-2015 Intel Corporation.
*
* Author: David Woodhouse <dwmw2@infradead.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* version 2.1, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
#include <config.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <ctype.h>
#include "openconnect-internal.h"
#include <openssl/crypto.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/engine.h>
#include <openssl/evp.h>
#include <openssl/rand.h>
#include <openssl/pkcs12.h>
#include <openssl/x509v3.h>
#include <openssl/x509.h>
#include <openssl/bio.h>
#include <openssl/ui.h>
#include <openssl/rsa.h>
#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
#define X509_up_ref(x) CRYPTO_add(&(x)->references, 1, CRYPTO_LOCK_X509)
#define X509_get0_notAfter(x) X509_get_notAfter(x)
#define EVP_MD_CTX_new EVP_MD_CTX_create
#define EVP_MD_CTX_free EVP_MD_CTX_destroy
#define X509_STORE_CTX_get0_chain(ctx) ((ctx)->chain)
#define X509_STORE_CTX_get0_untrusted(ctx) ((ctx)->untrusted)
#define X509_STORE_CTX_get0_cert(ctx) ((ctx)->cert)
typedef int (*X509_STORE_CTX_get_issuer_fn)(X509 **issuer,
X509_STORE_CTX *ctx, X509 *x);
#define X509_STORE_CTX_get_get_issuer(ctx) ((ctx)->get_issuer)
#endif
static char tls_library_version[32] = "";
const char *openconnect_get_tls_library_version()
{
if (!*tls_library_version) {
strncpy(tls_library_version, SSLeay_version(SSLEAY_VERSION), sizeof(tls_library_version));
tls_library_version[sizeof(tls_library_version)-1]='\0';
}
return tls_library_version;
}
int can_enable_insecure_crypto()
{
if (EVP_des_ede3_cbc() == NULL ||
EVP_rc4() == NULL)
return -ENOENT;
return 0;
}
int openconnect_sha1(unsigned char *result, void *data, int len)
{
EVP_MD_CTX *c = EVP_MD_CTX_new();
if (!c)
return -ENOMEM;
EVP_Digest(data, len, result, NULL, EVP_sha1(), NULL);
EVP_MD_CTX_free(c);
return 0;
}
int openconnect_sha256(unsigned char *result, void *data, int len)
{
EVP_MD_CTX *c = EVP_MD_CTX_new();
if (!c)
return -ENOMEM;
EVP_Digest(data, len, result, NULL, EVP_sha256(), NULL);
EVP_MD_CTX_free(c);
return 0;
}
int openconnect_md5(unsigned char *result, void *data, int len)
{
EVP_MD_CTX *c = EVP_MD_CTX_new();
if (!c)
return -ENOMEM;
EVP_Digest(data, len, result, NULL, EVP_md5(), NULL);
EVP_MD_CTX_free(c);
return 0;
}
int openconnect_get_peer_cert_DER(struct openconnect_info *vpninfo,
unsigned char **buf)
{
BIO *bp = BIO_new(BIO_s_mem());
BUF_MEM *certinfo;
size_t l;
if (!i2d_X509_bio(bp, vpninfo->peer_cert)) {
BIO_free(bp);
return -EIO;
}
BIO_get_mem_ptr(bp, &certinfo);
l = certinfo->length;
*buf = malloc(l);
if (!*buf) {
BIO_free(bp);
return -ENOMEM;
}
memcpy(*buf, certinfo->data, l);
BIO_free(bp);
return l;
}
int openconnect_random(void *bytes, int len)
{
if (RAND_bytes(bytes, len) != 1)
return -EIO;
return 0;
}
/* Helper functions for reading/writing lines over TLS/DTLS.
We could use cURL for the HTTP stuff, but it's overkill */
static int _openconnect_openssl_write(SSL *ssl, int fd, struct openconnect_info *vpninfo, char *buf, size_t len)
{
size_t orig_len = len;
while (len) {
int done = SSL_write(ssl, buf, len);
if (done > 0)
len -= done;
else {
int err = SSL_get_error(ssl, done);
fd_set wr_set, rd_set;
int maxfd = fd;
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (err == SSL_ERROR_WANT_READ)
FD_SET(fd, &rd_set);
else if (err == SSL_ERROR_WANT_WRITE)
FD_SET(fd, &wr_set);
else {
vpn_progress(vpninfo, PRG_ERR, _("Failed to write to TLS/DTLS socket\n"));
openconnect_report_ssl_errors(vpninfo);
return -EIO;
}
cmd_fd_set(vpninfo, &rd_set, &maxfd);
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (is_cancel_pending(vpninfo, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("TLS/DTLS write cancelled\n"));
return -EINTR;
}
}
}
return orig_len;
}
static int openconnect_openssl_write(struct openconnect_info *vpninfo, char *buf, size_t len)
{
return _openconnect_openssl_write(vpninfo->https_ssl, vpninfo->ssl_fd, vpninfo, buf, len);
}
int openconnect_dtls_write(struct openconnect_info *vpninfo, void *buf, size_t len)
{
return _openconnect_openssl_write(vpninfo->dtls_ssl, vpninfo->dtls_fd, vpninfo, buf, len);
}
/* set ms to zero for no timeout */
static int _openconnect_openssl_read(SSL *ssl, int fd, struct openconnect_info *vpninfo, char *buf, size_t len, unsigned ms)
{
int done, ret;
struct timeval timeout, *tv = NULL;
if (ms) {
timeout.tv_sec = ms/1000;
timeout.tv_usec = (ms%1000)*1000;
tv = &timeout;
}
while ((done = SSL_read(ssl, buf, len)) == -1) {
int err = SSL_get_error(ssl, done);
fd_set wr_set, rd_set;
int maxfd = fd;
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (err == SSL_ERROR_WANT_READ)
FD_SET(fd, &rd_set);
else if (err == SSL_ERROR_WANT_WRITE)
FD_SET(fd, &wr_set);
else {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from TLS/DTLS socket\n"));
openconnect_report_ssl_errors(vpninfo);
return -EIO;
}
cmd_fd_set(vpninfo, &rd_set, &maxfd);
ret = select(maxfd + 1, &rd_set, &wr_set, NULL, tv);
if (is_cancel_pending(vpninfo, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("TLS/DTLS read cancelled\n"));
return -EINTR;
}
if (ret == 0) {
return -ETIMEDOUT;
}
}
return done;
}
static int openconnect_openssl_read(struct openconnect_info *vpninfo, char *buf, size_t len)
{
return _openconnect_openssl_read(vpninfo->https_ssl, vpninfo->ssl_fd, vpninfo, buf, len, 0);
}
int openconnect_dtls_read(struct openconnect_info *vpninfo, void *buf, size_t len, unsigned ms)
{
return _openconnect_openssl_read(vpninfo->dtls_ssl, vpninfo->dtls_fd, vpninfo, buf, len, ms);
}
static int openconnect_openssl_gets(struct openconnect_info *vpninfo, char *buf, size_t len)
{
int i = 0;
int ret;
if (len < 2)
return -EINVAL;
while (1) {
ret = SSL_read(vpninfo->https_ssl, buf + i, 1);
if (ret == 1) {
if (buf[i] == '\n') {
buf[i] = 0;
if (i && buf[i-1] == '\r') {
buf[i-1] = 0;
i--;
}
return i;
}
i++;
if (i >= len - 1) {
buf[i] = 0;
return i;
}
} else {
fd_set rd_set, wr_set;
int maxfd = vpninfo->ssl_fd;
FD_ZERO(&rd_set);
FD_ZERO(&wr_set);
ret = SSL_get_error(vpninfo->https_ssl, ret);
if (ret == SSL_ERROR_WANT_READ)
FD_SET(vpninfo->ssl_fd, &rd_set);
else if (ret == SSL_ERROR_WANT_WRITE)
FD_SET(vpninfo->ssl_fd, &wr_set);
else {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from TLS/DTLS socket\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EIO;
break;
}
cmd_fd_set(vpninfo, &rd_set, &maxfd);
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (is_cancel_pending(vpninfo, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("TLS/DTLS read cancelled\n"));
ret = -EINTR;
break;
}
}
}
buf[i] = 0;
return i ?: ret;
}
int ssl_nonblock_read(struct openconnect_info *vpninfo, void *buf, int maxlen)
{
int len, ret;
len = SSL_read(vpninfo->https_ssl, buf, maxlen);
if (len > 0)
return len;
ret = SSL_get_error(vpninfo->https_ssl, len);
if (ret == SSL_ERROR_SYSCALL || ret == SSL_ERROR_ZERO_RETURN) {
vpn_progress(vpninfo, PRG_ERR,
_("SSL read error %d (server probably closed connection); reconnecting.\n"),
ret);
return -EIO;
}
return 0;
}
int ssl_nonblock_write(struct openconnect_info *vpninfo, void *buf, int buflen)
{
int ret;
ret = SSL_write(vpninfo->https_ssl, buf, buflen);
if (ret > 0)
return ret;
ret = SSL_get_error(vpninfo->https_ssl, ret);
switch (ret) {
case SSL_ERROR_WANT_WRITE:
/* Waiting for the socket to become writable -- it's
probably stalled, and/or the buffers are full */
monitor_write_fd(vpninfo, ssl);
case SSL_ERROR_WANT_READ:
return 0;
default:
vpn_progress(vpninfo, PRG_ERR, _("SSL_write failed: %d\n"), ret);
openconnect_report_ssl_errors(vpninfo);
return -1;
}
}
/* UI handling. All this just to handle the PIN callback from the TPM ENGINE,
and turn it into a call to our ->process_auth_form function */
struct ui_data {
struct openconnect_info *vpninfo;
struct oc_form_opt **last_opt;
struct oc_auth_form form;
};
struct ui_form_opt {
struct oc_form_opt opt;
UI_STRING *uis;
};
#ifdef HAVE_ENGINE
static int ui_open(UI *ui)
{
struct openconnect_info *vpninfo = UI_get0_user_data(ui);
struct ui_data *ui_data;
if (!vpninfo || !vpninfo->process_auth_form)
return 0;
ui_data = malloc(sizeof(*ui_data));
if (!ui_data)
return 0;
memset(ui_data, 0, sizeof(*ui_data));
ui_data->last_opt = &ui_data->form.opts;
ui_data->vpninfo = vpninfo;
ui_data->form.auth_id = (char *)"openssl_ui";
UI_add_user_data(ui, ui_data);
return 1;
}
static int ui_write(UI *ui, UI_STRING *uis)
{
struct ui_data *ui_data = UI_get0_user_data(ui);
struct ui_form_opt *opt;
switch (UI_get_string_type(uis)) {
case UIT_ERROR:
ui_data->form.error = (char *)UI_get0_output_string(uis);
break;
case UIT_INFO:
ui_data->form.message = (char *)UI_get0_output_string(uis);
break;
case UIT_PROMPT:
opt = malloc(sizeof(*opt));
if (!opt)
return 1;
memset(opt, 0, sizeof(*opt));
opt->uis = uis;
opt->opt.label = opt->opt.name = (char *)UI_get0_output_string(uis);
if (UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO)
opt->opt.type = OC_FORM_OPT_TEXT;
else
opt->opt.type = OC_FORM_OPT_PASSWORD;
*(ui_data->last_opt) = &opt->opt;
ui_data->last_opt = &opt->opt.next;
break;
default:
vpn_progress(ui_data->vpninfo, PRG_ERR,
_("Unhandled SSL UI request type %d\n"),
UI_get_string_type(uis));
return 0;
}
return 1;
}
static int ui_flush(UI *ui)
{
struct ui_data *ui_data = UI_get0_user_data(ui);
struct openconnect_info *vpninfo = ui_data->vpninfo;
struct ui_form_opt *opt;
int ret;
ret = process_auth_form(vpninfo, &ui_data->form);
if (ret)
return 0;
for (opt = (struct ui_form_opt *)ui_data->form.opts; opt;
opt = (struct ui_form_opt *)opt->opt.next) {
if (opt->opt._value && opt->uis)
UI_set_result(ui, opt->uis, opt->opt._value);
}
return 1;
}
static int ui_close(UI *ui)
{
struct ui_data *ui_data = UI_get0_user_data(ui);
struct ui_form_opt *opt, *next_opt;
opt = (struct ui_form_opt *)ui_data->form.opts;
while (opt) {
next_opt = (struct ui_form_opt *)opt->opt.next;
if (opt->opt._value)
free(opt->opt._value);
free(opt);
opt = next_opt;
}
free(ui_data);
UI_add_user_data(ui, NULL);
return 1;
}
static UI_METHOD *create_openssl_ui(void)
{
UI_METHOD *ui_method = UI_create_method((char *)"AnyConnect VPN UI");
/* Set up a UI method of our own for password/passphrase requests */
UI_method_set_opener(ui_method, ui_open);
UI_method_set_writer(ui_method, ui_write);
UI_method_set_flusher(ui_method, ui_flush);
UI_method_set_closer(ui_method, ui_close);
return ui_method;
}
#endif
static int pem_pw_cb(char *buf, int len, int w, void *v)
{
struct openconnect_info *vpninfo = v;
char *pass = NULL;
int plen;
if (vpninfo->cert_password) {
pass = vpninfo->cert_password;
vpninfo->cert_password = NULL;
} else if (request_passphrase(vpninfo, "openconnect_pem",
&pass, _("Enter PEM pass phrase:")))
return -1;
plen = strlen(pass);
if (len <= plen) {
vpn_progress(vpninfo, PRG_ERR,
_("PEM password too long (%d >= %d)\n"),
plen, len);
free_pass(&pass);
return -1;
}
memcpy(buf, pass, plen+1);
free_pass(&pass);
return plen;
}
static int install_extra_certs(struct openconnect_info *vpninfo, const char *source,
STACK_OF(X509) *ca)
{
X509 *cert = vpninfo->cert_x509;
int i;
if (!cert)
return -EINVAL;
next:
for (i = 0; i < sk_X509_num(ca); i++) {
X509 *cert2 = sk_X509_value(ca, i);
if (X509_check_issued(cert2, cert) == X509_V_OK) {
char buf[200];
if (cert2 == cert)
break;
if (X509_check_issued(cert2, cert2) == X509_V_OK)
break;
X509_NAME_oneline(X509_get_subject_name(cert2),
buf, sizeof(buf));
vpn_progress(vpninfo, PRG_DEBUG,
_("Extra cert from %s: '%s'\n"), source, buf);
X509_up_ref(cert2);
SSL_CTX_add_extra_chain_cert(vpninfo->https_ctx, cert2);
cert = cert2;
goto next;
}
}
sk_X509_pop_free(ca, X509_free);
return 0;
}
static int load_pkcs12_certificate(struct openconnect_info *vpninfo, PKCS12 *p12)
{
EVP_PKEY *pkey = NULL;
X509 *cert = NULL;
STACK_OF(X509) *ca;
int ret = 0;
char *pass;
pass = vpninfo->cert_password;
vpninfo->cert_password = NULL;
retrypass:
/* We do this every time round the loop, to work around a bug in
OpenSSL < 1.0.0-beta2 -- where the stack at *ca will be freed
when PKCS12_parse() returns an error, but *ca is left pointing
to the freed memory. */
ca = NULL;
if (!PKCS12_parse(p12, pass, &pkey, &cert, &ca)) {
unsigned long err = ERR_peek_error();
if (ERR_GET_LIB(err) == ERR_LIB_PKCS12 &&
ERR_GET_FUNC(err) == PKCS12_F_PKCS12_PARSE &&
ERR_GET_REASON(err) == PKCS12_R_MAC_VERIFY_FAILURE) {
if (pass)
vpn_progress(vpninfo, PRG_ERR,
_("Failed to decrypt PKCS#12 certificate file\n"));
free_pass(&pass);
if (request_passphrase(vpninfo, "openconnect_pkcs12", &pass,
_("Enter PKCS#12 pass phrase:")) < 0) {
PKCS12_free(p12);
return -EINVAL;
}
goto retrypass;
}
openconnect_report_ssl_errors(vpninfo);
vpn_progress(vpninfo, PRG_ERR,
_("Parse PKCS#12 failed (see above errors)\n"));
PKCS12_free(p12);
free_pass(&pass);
return -EINVAL;
}
free_pass(&pass);
if (cert) {
char buf[200];
vpninfo->cert_x509 = cert;
SSL_CTX_use_certificate(vpninfo->https_ctx, cert);
X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
vpn_progress(vpninfo, PRG_INFO,
_("Using client certificate '%s'\n"), buf);
} else {
vpn_progress(vpninfo, PRG_ERR,
_("PKCS#12 contained no certificate!\n"));
ret = -EINVAL;
}
if (pkey) {
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, pkey)) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
EVP_PKEY_free(pkey);
} else {
vpn_progress(vpninfo, PRG_ERR,
_("PKCS#12 contained no private key!\n"));
ret = -EINVAL;
}
if (ca)
install_extra_certs(vpninfo, _("PKCS#12"), ca);
PKCS12_free(p12);
return ret;
}
#ifdef HAVE_ENGINE
static int load_tpm_certificate(struct openconnect_info *vpninfo,
const char *engine)
{
ENGINE *e;
EVP_PKEY *key;
UI_METHOD *meth = NULL;
int ret = 0;
ENGINE_load_builtin_engines();
e = ENGINE_by_id(engine);
if (!e && !strcmp(engine, "tpm2")) {
ERR_clear_error();
e = ENGINE_by_id("tpm2tss");
}
if (!e) {
vpn_progress(vpninfo, PRG_ERR, _("Can't load TPM engine.\n"));
openconnect_report_ssl_errors(vpninfo);
return -EINVAL;
}
if (!ENGINE_init(e) || !ENGINE_set_default_RSA(e) ||
!ENGINE_set_default_RAND(e)) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to init TPM engine\n"));
openconnect_report_ssl_errors(vpninfo);
ENGINE_free(e);
return -EINVAL;
}
if (vpninfo->cert_password) {
if (!ENGINE_ctrl_cmd(e, "PIN", strlen(vpninfo->cert_password),
vpninfo->cert_password, NULL, 0)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to set TPM SRK password\n"));
openconnect_report_ssl_errors(vpninfo);
}
free_pass(&vpninfo->cert_password);
}
/* Provide our own UI method to handle the PIN callback. */
meth = create_openssl_ui();
key = ENGINE_load_private_key(e, vpninfo->sslkey, meth, vpninfo);
if (meth)
UI_destroy_method(meth);
if (!key) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load TPM private key\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
goto out;
}
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR, _("Add key from TPM failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
EVP_PKEY_free(key);
out:
ENGINE_finish(e);
ENGINE_free(e);
return ret;
}
#else
static int load_tpm_certificate(struct openconnect_info *vpninfo,
const char *engine)
{
vpn_progress(vpninfo, PRG_ERR,
_("This version of OpenConnect was built without TPM support\n"));
return -EINVAL;
}
#endif
/* This is a reimplementation of SSL_CTX_use_certificate_chain_file().
* We do this for three reasons:
*
* - Firstly, we have no way to obtain the primary X509 certificate
* after SSL_CTX_use_certificate_chain_file() has loaded it, and we
* need to inspect it to check for expiry and report its name etc.
* So in the past we've opened the cert file again and read the cert
* again in a reload_pem_cert() function which was a partial
* reimplementation anyway.
*
* - Secondly, on Windows, OpenSSL only partially handles UTF-8 filenames.
* Specifically, BIO_new_file() will convert UTF-8 to UTF-16 and attempt
* to use _wfopen() to open the file, but BIO_read_filename() will not.
* It is BIO_read_filename() which the SSL_CTX_*_file functions use, and
* thus they don't work with UTF-8 file names. This is filed as RT#3479:
* http://rt.openssl.org/Ticket/Display.html?id=3479
*
* - Finally, and least importantly, it does actually matter which supporting
* certs we offer on the wire because of RT#1942. Doing this for ourselves
* allows us to explicitly print the supporting certs that we're using,
* which may assist in diagnosing problems.
*/
static int load_cert_chain_file(struct openconnect_info *vpninfo)
{
BIO *b;
FILE *f = openconnect_fopen_utf8(vpninfo, vpninfo->cert, "rb");
STACK_OF(X509) *extra_certs = NULL;
char buf[200];
if (!f) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open certificate file %s: %s\n"),
vpninfo->cert, strerror(errno));
return -ENOENT;
}
b = BIO_new_fp(f, 1);
if (!b) {
fclose(f);
err:
vpn_progress(vpninfo, PRG_ERR,
_("Loading certificate failed\n"));
openconnect_report_ssl_errors(vpninfo);
return -EIO;
}
vpninfo->cert_x509 = PEM_read_bio_X509_AUX(b, NULL, NULL, NULL);
if (!vpninfo->cert_x509) {
BIO_free(b);
goto err;
}
X509_NAME_oneline(X509_get_subject_name(vpninfo->cert_x509), buf, sizeof(buf));
vpn_progress(vpninfo, PRG_INFO,
_("Using client certificate '%s'\n"), buf);
if (!SSL_CTX_use_certificate(vpninfo->https_ctx, vpninfo->cert_x509)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to install certificate in OpenSSL context\n"));
openconnect_report_ssl_errors(vpninfo);
BIO_free(b);
return -EIO;
}
while (1) {
X509 *x = PEM_read_bio_X509(b, NULL, NULL, NULL);
if (!x) {
unsigned long err = ERR_peek_last_error();
if (ERR_GET_LIB(err) == ERR_LIB_PEM &&
ERR_GET_REASON(err) == PEM_R_NO_START_LINE)
ERR_clear_error();
else
goto err_extra;
break;
}
if (!extra_certs)
extra_certs = sk_X509_new_null();
if (!extra_certs) {
err_extra:
vpn_progress(vpninfo, PRG_ERR,
_("Failed to process all supporting certs. Trying anyway...\n"));
openconnect_report_ssl_errors(vpninfo);
X509_free(x);
/* It might work without... */
break;
}
if (!sk_X509_push(extra_certs, x))
goto err_extra;
}
BIO_free(b);
if (extra_certs)
install_extra_certs(vpninfo, _("PEM file"), extra_certs);
return 0;
}
#ifdef ANDROID_KEYSTORE
static BIO *BIO_from_keystore(struct openconnect_info *vpninfo, const char *item)
{
unsigned char *content;
BIO *b;
int len;
const char *p = item + 9;
/* Skip first two slashes if the user has given it as
keystore://foo ... */
if (*p == '/')
p++;
if (*p == '/')
p++;
len = keystore_fetch(p, &content);
if (len < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load item '%s' from keystore: %s\n"),
p, keystore_strerror(len));
return NULL;
}
if (!(b = BIO_new(BIO_s_mem())) || BIO_write(b, content, len) != len) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to create BIO for keystore item '%s'\n"),
p);
free(content);
BIO_free(b);
return NULL;
}
free(content);
return b;
}
#endif
static int is_pem_password_error(struct openconnect_info *vpninfo)
{
unsigned long err = ERR_peek_error();
openconnect_report_ssl_errors(vpninfo);
#ifndef EVP_F_EVP_DECRYPTFINAL_EX
#define EVP_F_EVP_DECRYPTFINAL_EX EVP_F_EVP_DECRYPTFINAL
#endif
/* If the user fat-fingered the passphrase, try again */
if (ERR_GET_LIB(err) == ERR_LIB_EVP &&
ERR_GET_FUNC(err) == EVP_F_EVP_DECRYPTFINAL_EX &&
ERR_GET_REASON(err) == EVP_R_BAD_DECRYPT) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed (wrong passphrase?)\n"));
ERR_clear_error();
return 1;
}
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed (see above errors)\n"));
return 0;
}
static int load_certificate(struct openconnect_info *vpninfo)
{
EVP_PKEY *key;
FILE *f;
char buf[256];
int ret;
if (!strncmp(vpninfo->cert, "pkcs11:", 7)) {
int ret = load_pkcs11_certificate(vpninfo);
if (ret)
return ret;
goto got_cert;
}
vpn_progress(vpninfo, PRG_DEBUG,
_("Using certificate file %s\n"), vpninfo->cert);
if (strncmp(vpninfo->cert, "keystore:", 9)) {
PKCS12 *p12;
f = openconnect_fopen_utf8(vpninfo, vpninfo->cert, "rb");
if (!f) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open certificate file %s: %s\n"),
vpninfo->cert, strerror(errno));
return -ENOENT;
}
p12 = d2i_PKCS12_fp(f, NULL);
fclose(f);
if (p12)
return load_pkcs12_certificate(vpninfo, p12);
/* Not PKCS#12. Clear error and fall through to see if it's a PEM file... */
ERR_clear_error();
}
/* It's PEM or TPM now, and either way we need to load the plain cert: */
#ifdef ANDROID_KEYSTORE
if (!strncmp(vpninfo->cert, "keystore:", 9)) {
BIO *b = BIO_from_keystore(vpninfo, vpninfo->cert);
if (!b)
return -EINVAL;
vpninfo->cert_x509 = PEM_read_bio_X509_AUX(b, NULL, pem_pw_cb, vpninfo);
BIO_free(b);
if (!vpninfo->cert_x509) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load X509 certificate from keystore\n"));
openconnect_report_ssl_errors(vpninfo);
return -EINVAL;
}
if (!SSL_CTX_use_certificate(vpninfo->https_ctx, vpninfo->cert_x509)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to use X509 certificate from keystore\n"));
openconnect_report_ssl_errors(vpninfo);
X509_free(vpninfo->cert_x509);
vpninfo->cert_x509 = NULL;
return -EINVAL;
}
} else
#endif /* ANDROID_KEYSTORE */
{
int ret = load_cert_chain_file(vpninfo);
if (ret)
return ret;
}
got_cert:
#ifdef ANDROID_KEYSTORE
if (!strncmp(vpninfo->sslkey, "keystore:", 9)) {
BIO *b;
again_android:
b = BIO_from_keystore(vpninfo, vpninfo->sslkey);
if (!b)
return -EINVAL;
key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, vpninfo);
BIO_free(b);
if (!key) {
if (is_pem_password_error(vpninfo))
goto again_android;
return -EINVAL;
}
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to use private key from keystore\n"));
EVP_PKEY_free(key);
X509_free(vpninfo->cert_x509);
vpninfo->cert_x509 = NULL;
return -EINVAL;
}
EVP_PKEY_free(key);
return 0;
}
#endif /* ANDROID_KEYSTORE */
if (!strncmp(vpninfo->sslkey, "pkcs11:", 7))
return load_pkcs11_key(vpninfo);
f = openconnect_fopen_utf8(vpninfo, vpninfo->sslkey, "rb");
if (!f) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open private key file %s: %s\n"),
vpninfo->sslkey, strerror(errno));
return -ENOENT;
}
buf[255] = 0;
while (fgets(buf, 255, f)) {
if (!strcmp(buf, "-----BEGIN TSS KEY BLOB-----\n")) {
fclose(f);
return load_tpm_certificate(vpninfo, "tpm");
} else if (!strcmp(buf, "-----BEGIN TSS2 KEY BLOB-----\n") ||
!strcmp(buf, "-----BEGIN TSS2 PRIVATE KEY-----\n")) {
fclose(f);
return load_tpm_certificate(vpninfo, "tpm2");
} else if (!strcmp(buf, "-----BEGIN RSA PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN DSA PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN EC PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN ENCRYPTED PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN PRIVATE KEY-----\n")) {
BIO *b = BIO_new_fp(f, BIO_CLOSE);
if (!b) {
fclose(f);
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
return -EINVAL;
}
again:
fseek(f, 0, SEEK_SET);
key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, vpninfo);
if (!key) {
if (is_pem_password_error(vpninfo))
goto again;
BIO_free(b);
return -EINVAL;
}
ret = 0;
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
EVP_PKEY_free(key);
BIO_free(b);
return ret;
}
}
/* Not PEM? Try DER... */
fseek(f, 0, SEEK_SET);
/* This will catch PKCS#1 and unencrypted PKCS#8
* (except in OpenSSL 0.9.8 where it doesn't handle
* the latter but nobody cares about 0.9.8 any more. */
key = d2i_PrivateKey_fp(f, NULL);
if (key) {
ret = 0;
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;