/
gnutls.c
1620 lines (1423 loc) · 44 KB
/
gnutls.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 © 2008-2012 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.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to:
*
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netdb.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <ctype.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdarg.h>
#include <stdlib.h>
#include <gnutls/gnutls.h>
#include <gnutls/x509.h>
#include <gnutls/crypto.h>
#include <gnutls/pkcs12.h>
#include <gnutls/abstract.h>
#ifdef HAVE_TROUSERS
#include <trousers/tss.h>
#include <trousers/trousers.h>
#endif
#ifdef HAVE_P11KIT
#include <p11-kit/p11-kit.h>
#include <p11-kit/pkcs11.h>
#include <p11-kit/pin.h>
static P11KitPin *pin_callback(const char *pin_source, P11KitUri *pin_uri,
const char *pin_description,
P11KitPinFlags flags,
void *_vpninfo);
#endif
#include "openconnect-internal.h"
/* Helper functions for reading/writing lines over SSL.
We could use cURL for the HTTP stuff, but it's overkill */
int openconnect_SSL_write(struct openconnect_info *vpninfo, char *buf, size_t len)
{
size_t orig_len = len;
while (len) {
int done = gnutls_record_send(vpninfo->https_sess, buf, len);
if (done > 0)
len -= done;
else if (done != GNUTLS_E_AGAIN) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to write to SSL socket: %s"),
gnutls_strerror(done));
return -EIO;
} else {
fd_set wr_set, rd_set;
int maxfd = vpninfo->ssl_fd;
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (gnutls_record_get_direction(vpninfo->https_sess))
FD_SET(vpninfo->ssl_fd, &wr_set);
else
FD_SET(vpninfo->ssl_fd, &rd_set);
if (vpninfo->cancel_fd != -1) {
FD_SET(vpninfo->cancel_fd, &rd_set);
if (vpninfo->cancel_fd > vpninfo->ssl_fd)
maxfd = vpninfo->cancel_fd;
}
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (vpninfo->cancel_fd != -1 &&
FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL write cancelled\n"));
return -EINTR;
}
}
}
return orig_len;
}
int openconnect_SSL_read(struct openconnect_info *vpninfo, char *buf, size_t len)
{
int done;
while ((done = gnutls_record_recv(vpninfo->https_sess, buf, len)) < 0) {
fd_set wr_set, rd_set;
int maxfd = vpninfo->ssl_fd;
if (done != GNUTLS_E_AGAIN) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from SSL socket: %s"),
gnutls_strerror(done));
return -EIO;
} else {
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (gnutls_record_get_direction(vpninfo->https_sess))
FD_SET(vpninfo->ssl_fd, &wr_set);
else
FD_SET(vpninfo->ssl_fd, &rd_set);
if (vpninfo->cancel_fd != -1) {
FD_SET(vpninfo->cancel_fd, &rd_set);
if (vpninfo->cancel_fd > vpninfo->ssl_fd)
maxfd = vpninfo->cancel_fd;
}
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (vpninfo->cancel_fd != -1 &&
FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL read cancelled\n"));
return -EINTR;
}
}
}
return done;
}
int openconnect_SSL_gets(struct openconnect_info *vpninfo, char *buf, size_t len)
{
int i = 0;
int ret;
if (len < 2)
return -EINVAL;
while (1) {
ret = gnutls_record_recv(vpninfo->https_sess, 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 if (ret != GNUTLS_E_AGAIN) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from SSL socket: %s\n"),
gnutls_strerror(ret));
ret = -EIO;
break;
} else {
fd_set rd_set, wr_set;
int maxfd = vpninfo->ssl_fd;
FD_ZERO(&rd_set);
FD_ZERO(&wr_set);
if (gnutls_record_get_direction(vpninfo->https_sess))
FD_SET(vpninfo->ssl_fd, &wr_set);
else
FD_SET(vpninfo->ssl_fd, &rd_set);
if (vpninfo->cancel_fd != -1) {
FD_SET(vpninfo->cancel_fd, &rd_set);
if (vpninfo->cancel_fd > vpninfo->ssl_fd)
maxfd = vpninfo->cancel_fd;
}
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (vpninfo->cancel_fd != -1 &&
FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL read cancelled\n"));
ret = -EINTR;
break;
}
}
}
buf[i] = 0;
return i ?: ret;
}
static int check_certificate_expiry(struct openconnect_info *vpninfo, gnutls_x509_crt_t cert)
{
const char *reason = NULL;
time_t expires = gnutls_x509_crt_get_expiration_time(cert);
time_t now = time(NULL);
if (expires == -1) {
vpn_progress(vpninfo, PRG_ERR,
_("Could not extract expiration time of certificate\n"));
return -EINVAL;
}
if (expires < now)
reason = _("Client certificate has expired at");
else if (expires < now + vpninfo->cert_expire_warning)
reason = _("Client certificate expires soon at");
if (reason) {
struct tm tm;
char buf[80];
gmtime_r(&expires, &tm);
strftime(buf, 80, "%a, %d %b %Y %T %Z", &tm);
vpn_progress(vpninfo, PRG_ERR, "%s: %s\n", reason, buf);
}
return 0;
}
/* For systems that don't support O_CLOEXEC, just don't bother.
It's not open for long anyway. */
#ifndef O_CLOEXEC
#define O_CLOEXEC
#endif
static int load_datum(struct openconnect_info *vpninfo,
gnutls_datum_t *datum, const char *fname)
{
struct stat st;
int fd, err;
fd = open(fname, O_RDONLY|O_CLOEXEC);
if (fd == -1) {
err = errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open key/certificate file %s: %s\n"),
fname, strerror(err));
return -ENOENT;
}
if (fstat(fd, &st)) {
err = errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to stat key/certificate file %s: %s\n"),
fname, strerror(err));
close(fd);
return -EIO;
}
datum->size = st.st_size;
datum->data = gnutls_malloc(st.st_size + 1);
if (!datum->data) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to allocate certificate buffer\n"));
close(fd);
return -ENOMEM;
}
errno = EAGAIN;
if (read(fd, datum->data, datum->size) != datum->size) {
err = errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to read certificate into memory: %s\n"),
strerror(err));
close(fd);
gnutls_free(datum->data);
return -EIO;
}
datum->data[st.st_size] = 0;
close(fd);
return 0;
}
#ifndef HAVE_GNUTLS_PKCS12_SIMPLE_PARSE
/* If we're using a version of GnuTLS from before this was
exported, pull in our local copy. */
#include "gnutls_pkcs12.c"
#endif
/* A non-zero, non-error return to make load_certificate() continue and
interpreting the file as other types */
#define NOT_PKCS12 1
static int load_pkcs12_certificate(struct openconnect_info *vpninfo,
gnutls_datum_t *datum,
gnutls_x509_privkey_t *key,
gnutls_x509_crt_t **chain,
unsigned int *chain_len,
gnutls_x509_crt_t **extra_certs,
unsigned int *extra_certs_len,
gnutls_x509_crl_t *crl)
{
gnutls_pkcs12_t p12;
char *pass;
int err;
err = gnutls_pkcs12_init(&p12);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to setup PKCS#12 data structure: %s\n"),
gnutls_strerror(err));
return -EIO;
}
err = gnutls_pkcs12_import(p12, datum, GNUTLS_X509_FMT_DER, 0);
if (err) {
gnutls_pkcs12_deinit(p12);
if (vpninfo->cert_type == CERT_TYPE_UNKNOWN)
return NOT_PKCS12;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to import PKCS#12 file: %s\n"),
gnutls_strerror(err));
return -EINVAL;
}
pass = vpninfo->cert_password;
while ((err = gnutls_pkcs12_verify_mac(p12, pass)) == GNUTLS_E_MAC_VERIFY_FAILED) {
if (pass)
vpn_progress(vpninfo, PRG_ERR,
_("Failed to decrypt PKCS#12 certificate file\n"));
free(pass);
vpninfo->cert_password = NULL;
err = request_passphrase(vpninfo, &pass,
_("Enter PKCS#12 pass phrase:"));
if (err) {
gnutls_pkcs12_deinit(p12);
return -EINVAL;
}
}
/* If it wasn't GNUTLS_E_MAC_VERIFY_FAILED, then the problem wasn't just a
bad password. Give up. */
if (err) {
int level = PRG_ERR;
int ret = -EINVAL;
gnutls_pkcs12_deinit(p12);
/* If the first attempt, and we didn't know for sure it was PKCS#12
anyway, bail out and try loading it as something different. */
if (pass == vpninfo->cert_password &&
vpninfo->cert_type == CERT_TYPE_UNKNOWN) {
/* Make it non-fatal... */
level = PRG_TRACE;
ret = NOT_PKCS12;
}
vpn_progress(vpninfo, level,
_("Failed to process PKCS#12 file: %s\n"),
gnutls_strerror(err));
return ret;
}
err = gnutls_pkcs12_simple_parse(p12, pass, key, chain, chain_len,
extra_certs, extra_certs_len, crl, 0);
free(pass);
vpninfo->cert_password = NULL;
gnutls_pkcs12_deinit(p12);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load PKCS#12 certificate: %s\n"),
gnutls_strerror(err));
return -EINVAL;
}
return 0;
}
/* Older versions of GnuTLS didn't actually bother to check this, so we'll
do it for them. */
static int check_issuer_sanity(gnutls_x509_crt_t cert, gnutls_x509_crt_t issuer)
{
#if GNUTLS_VERSION_NUMBER > 0x300014
return 0;
#else
unsigned char id1[512], id2[512];
size_t id1_size = 512, id2_size = 512;
int err;
err = gnutls_x509_crt_get_authority_key_id(cert, id1, &id1_size, NULL);
if (err)
return 0;
err = gnutls_x509_crt_get_subject_key_id(issuer, id2, &id2_size, NULL);
if (err)
return 0;
if (id1_size == id2_size && !memcmp(id1, id2, id1_size))
return 0;
/* EEP! */
return -EIO;
#endif
}
static int count_x509_certificates(gnutls_datum_t *datum)
{
int count = 0;
char *p = (char *)datum->data;
while (p) {
p = strstr(p, "-----BEGIN ");
if (!p)
break;
p += 11;
if (!strncmp(p, "CERTIFICATE", 11) ||
!strncmp(p, "X509 CERTIFICATE", 16))
count++;
}
return count;
}
static int get_cert_name(gnutls_x509_crt_t cert, char *name, size_t namelen)
{
if (gnutls_x509_crt_get_dn_by_oid(cert, GNUTLS_OID_X520_COMMON_NAME,
0, 0, name, &namelen) &&
gnutls_x509_crt_get_dn(cert, name, &namelen)) {
name[namelen-1] = 0;
snprintf(name, namelen-1, "<unknown>");
return -EINVAL;
}
return 0;
}
#ifdef HAVE_TROUSERS
/* TPM code based on client-tpm.c from Carolin Latze <latze@angry-red-pla.net>
and Tobias Soder */
static int tpm_sign_fn(gnutls_privkey_t key, void *_vpninfo,
const gnutls_datum_t *data, gnutls_datum_t *sig)
{
struct openconnect_info *vpninfo = _vpninfo;
TSS_HHASH hash;
int err;
vpn_progress(vpninfo, PRG_TRACE,
_("TPM sign function called for %d bytes.\n"),
data->size);
err = Tspi_Context_CreateObject(vpninfo->tpm_context, TSS_OBJECT_TYPE_HASH,
TSS_HASH_OTHER, &hash);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to create TPM hash object.\n"));
return GNUTLS_E_PK_SIGN_FAILED;
}
err = Tspi_Hash_SetHashValue(hash, data->size, data->data);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to set value in TPM hash object.\n"));
Tspi_Context_CloseObject(vpninfo->tpm_context, hash);
return GNUTLS_E_PK_SIGN_FAILED;
}
err = Tspi_Hash_Sign(hash, vpninfo->tpm_key, &sig->size, &sig->data);
Tspi_Context_CloseObject(vpninfo->tpm_context, hash);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("TPM hash signature failed\n"));
return GNUTLS_E_PK_SIGN_FAILED;
}
return 0;
}
static int load_tpm_key(struct openconnect_info *vpninfo, gnutls_datum_t *fdata, gnutls_privkey_t *pkey)
{
static const TSS_UUID SRK_UUID = TSS_UUID_SRK;
gnutls_datum_t asn1;
unsigned int tss_len;
char *pass;
int ofs, err;
err = gnutls_pem_base64_decode_alloc("TSS KEY BLOB", fdata, &asn1);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error decoding TSS key blob: %s\n"),
gnutls_strerror(err));
return -EINVAL;
}
/* Ick. We have to parse the ASN1 OCTET_STRING for ourselves. */
if (asn1.size < 2 || asn1.data[0] != 0x04 /* OCTET_STRING */) {
vpn_progress(vpninfo, PRG_ERR,
_("Error in TSS key blob\n"));
goto out_blob;
}
tss_len = asn1.data[1];
ofs = 2;
if (tss_len & 0x80) {
int lenlen = tss_len & 0x7f;
if (asn1.size < 2 + lenlen || lenlen > 3) {
vpn_progress(vpninfo, PRG_ERR,
_("Error in TSS key blob\n"));
goto out_blob;
}
tss_len = 0;
while (lenlen) {
tss_len <<= 8;
tss_len |= asn1.data[ofs++];
lenlen--;
}
}
if (tss_len + ofs != asn1.size) {
vpn_progress(vpninfo, PRG_ERR,
_("Error in TSS key blob\n"));
goto out_blob;
}
err = Tspi_Context_Create(&vpninfo->tpm_context);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to create TPM context: %s\n"),
Trspi_Error_String(err));
goto out_blob;
}
err = Tspi_Context_Connect(vpninfo->tpm_context, NULL);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to connect TPM context: %s\n"),
Trspi_Error_String(err));
goto out_context;
}
err = Tspi_Context_LoadKeyByUUID(vpninfo->tpm_context, TSS_PS_TYPE_SYSTEM,
SRK_UUID, &vpninfo->srk);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load TPM SRK key: %s\n"),
Trspi_Error_String(err));
goto out_context;
}
err = Tspi_GetPolicyObject(vpninfo->srk, TSS_POLICY_USAGE, &vpninfo->srk_policy);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load TPM SRK policy object: %s\n"),
Trspi_Error_String(err));
goto out_srk;
}
pass = vpninfo->cert_password;
vpninfo->cert_password = NULL;
while (1) {
if (!pass) {
err = request_passphrase(vpninfo, &pass, _("Enter TPM SRK PIN:"));
if (err)
goto out_srkpol;
}
/* We don't seem to get the error here... */
err = Tspi_Policy_SetSecret(vpninfo->srk_policy, TSS_SECRET_MODE_PLAIN,
strlen(pass), (void *)pass);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to set TPM PIN: %s\n"),
Trspi_Error_String(err));
goto out_srkpol;
}
free(pass);
pass = NULL;
/* ... we get it here instead. */
err = Tspi_Context_LoadKeyByBlob(vpninfo->tpm_context, vpninfo->srk,
tss_len, asn1.data + ofs, &vpninfo->tpm_key);
if (!err)
break;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load TPM key blob: %s\n"),
Trspi_Error_String(err));
if (err != TPM_E_AUTHFAIL)
goto out_srkpol;
}
gnutls_privkey_init(pkey);
/* This would be nicer if there was a destructor callback. I could
allocate a data structure with the TPM handles and the vpninfo
pointer, and destroy that properly when the key is destroyed. */
gnutls_privkey_import_ext(*pkey, GNUTLS_PK_RSA, vpninfo, tpm_sign_fn, NULL, 0);
/* FIXME: Get key id using TSS_TSPATTRIB_KEYINFO_RSA_MODULUS etc. so
that we can ensure we have a matching cert. */
free (asn1.data);
return 0;
out_srkpol:
Tspi_Context_CloseObject(vpninfo->tpm_context, vpninfo->srk_policy);
vpninfo->srk_policy = 0;
out_srk:
Tspi_Context_CloseObject(vpninfo->tpm_context, vpninfo->srk);
vpninfo->srk = 0;
out_context:
Tspi_Context_Close(vpninfo->tpm_context);
vpninfo->tpm_context = 0;
out_blob:
free (asn1.data);
return -EIO;
}
#endif /* HAVE_TROUSERS */
static int load_certificate(struct openconnect_info *vpninfo)
{
gnutls_datum_t fdata;
gnutls_x509_privkey_t key = NULL;
#ifdef HAVE_GNUTLS_CERTIFICATE_SET_KEY
gnutls_privkey_t pkey = NULL;
#endif
#ifdef HAVE_P11KIT
char *cert_url = (char *)vpninfo->cert;
char *key_url = (char *)vpninfo->sslkey;
#endif
gnutls_x509_crl_t crl = NULL;
gnutls_x509_crt_t last_cert, cert = NULL;
gnutls_x509_crt_t *extra_certs = NULL, *supporting_certs = NULL;
unsigned int nr_supporting_certs = 0, nr_extra_certs = 0;
unsigned int certs_to_free = 0; /* How many of supporting_certs */
int err; /* GnuTLS error */
int ret = 0; /* our error (zero or -errno) */
int i;
int cert_is_p11 = 0, key_is_p11 = 0;
unsigned char key_id[20];
size_t key_id_size = sizeof(key_id);
char name[80];
fdata.data = NULL;
key_is_p11 = !strncmp(vpninfo->sslkey, "pkcs11:", 7);
cert_is_p11 = !strncmp(vpninfo->cert, "pkcs11:", 7);
/* Install PIN handler if either certificate or key are coming from PKCS#11 */
if (key_is_p11 || cert_is_p11) {
#ifdef HAVE_P11KIT
CK_OBJECT_CLASS class;
CK_ATTRIBUTE attr;
char pin_source[40];
P11KitUri *uri;
sprintf(pin_source, "openconnect:%p", vpninfo);
p11_kit_pin_register_callback(pin_source, pin_callback, vpninfo, NULL);
uri = p11_kit_uri_new();
attr.type = CKA_CLASS;
attr.pValue = &class;
attr.ulValueLen = sizeof(class);
/* Add appropriate pin-source and object-type attributes to
both certificate and key URLs, unless they already exist. */
if (cert_is_p11 &&
!p11_kit_uri_parse(cert_url, P11_KIT_URI_FOR_OBJECT, uri)) {
if (!p11_kit_uri_get_pin_source(uri))
p11_kit_uri_set_pin_source(uri, pin_source);
if (!p11_kit_uri_get_attribute(uri, CKA_CLASS)) {
class = CKO_CERTIFICATE;
p11_kit_uri_set_attribute(uri, &attr);
}
p11_kit_uri_format(uri, P11_KIT_URI_FOR_OBJECT, &cert_url);
}
if (key_is_p11 &&
!p11_kit_uri_parse(key_url, P11_KIT_URI_FOR_OBJECT, uri)) {
if (!p11_kit_uri_get_pin_source(uri))
p11_kit_uri_set_pin_source(uri, pin_source);
if (!p11_kit_uri_get_attribute(uri, CKA_CLASS)) {
class = CKO_PRIVATE_KEY;
p11_kit_uri_set_attribute(uri, &attr);
}
p11_kit_uri_format(uri, P11_KIT_URI_FOR_OBJECT, &key_url);
}
p11_kit_uri_free(uri);
#else
vpn_progress(vpninfo, PRG_ERR,
_("This binary built without PKCS#11 support\n"));
return -EINVAL;
#endif
}
/* Load certificate(s) first... */
#ifdef HAVE_P11KIT
#ifndef HAVE_GNUTLS_CERTIFICATE_SET_KEY
if (key_is_p11) {
/* With GnuTLS 2.12 we can't *see* the key so we can't
do the expiry check or fill in intermediate CAs. */
err = gnutls_certificate_set_x509_key_file(vpninfo->https_cred,
cert_url, key_url,
GNUTLS_X509_FMT_PEM);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error loading PKCS#11 certificate: %s\n"),
gnutls_strerror(err));
ret = -EIO;
goto out;
}
ret = 0;
goto out;
}
#endif /* PKCS#11 for GnuTLS v2.12 */
/* GnuTLS 2.12 *can* handle the cert being in PKCS#11, if the key
isn't. Although it's not clear why anyone would ever do that. */
if (cert_is_p11) {
vpn_progress(vpninfo, PRG_TRACE,
_("Using PKCS#11 certificate %s\n"), cert_url);
err = gnutls_x509_crt_init(&cert);
if (err) {
ret = -ENOMEM;
goto out;
}
err = gnutls_x509_crt_import_pkcs11_url(cert, cert_url, 0);
if (err == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE)
err = gnutls_x509_crt_import_pkcs11_url(cert, cert_url,
GNUTLS_PKCS11_OBJ_FLAG_LOGIN);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error loading certificate from PKCS#11: %s\n"),
gnutls_strerror(err));
ret = -EIO;
goto out;
}
goto got_certs;
}
#endif /* HAVE_P11KIT */
vpn_progress(vpninfo, PRG_TRACE,
_("Using certificate file %s\n"), vpninfo->cert);
ret = load_datum(vpninfo, &fdata, vpninfo->cert);
if (ret)
return ret;
if (!key_is_p11 && (vpninfo->cert_type == CERT_TYPE_PKCS12 ||
vpninfo->cert_type == CERT_TYPE_UNKNOWN)) {
/* PKCS#12 should actually contain certificates *and* private key */
ret = load_pkcs12_certificate(vpninfo, &fdata, &key,
&supporting_certs, &nr_supporting_certs,
&extra_certs, &nr_extra_certs,
&crl);
if (ret < 0)
goto out;
else if (!ret) {
if (nr_supporting_certs) {
cert = supporting_certs[0];
goto got_key;
}
vpn_progress(vpninfo, PRG_ERR,
_("PKCS#11 file contained no certificate\n"));
ret = -EINVAL;
goto out;
}
/* It returned NOT_PKCS12.
Fall through to try PEM formats. */
}
/* We need to know how many there are in *advance*; it won't just allocate
the array for us :( */
nr_extra_certs = count_x509_certificates(&fdata);
if (!nr_extra_certs)
nr_extra_certs = 1; /* wtf? Oh well, we'll fail later... */
extra_certs = calloc(nr_extra_certs, sizeof(cert));
if (!extra_certs) {
nr_extra_certs = 0;
ret = -ENOMEM;
goto out;
}
err = gnutls_x509_crt_list_import(extra_certs, &nr_extra_certs, &fdata,
GNUTLS_X509_FMT_PEM, 0);
if (err <= 0) {
const char *reason;
if (!err || err == GNUTLS_E_NO_CERTIFICATE_FOUND)
reason = _("No certificate found in file");
else
reason = gnutls_strerror(err);
vpn_progress(vpninfo, PRG_ERR,
_("Loading certificate failed: %s\n"),
reason);
ret = -EINVAL;
goto out;
}
nr_extra_certs = err;
err = 0;
goto got_certs;
got_certs:
/* Now we have the certificate(s) and we're looking for the private key... */
#if defined (HAVE_P11KIT) && defined (HAVE_GNUTLS_CERTIFICATE_SET_KEY)
if (key_is_p11) {
gnutls_pkcs11_privkey_t p11key = NULL;
vpn_progress(vpninfo, PRG_TRACE,
_("Using PKCS#11 key %s\n"), key_url);
err = gnutls_pkcs11_privkey_init(&p11key);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error initialising PKCS#11 key structure: %s\n"),
gnutls_strerror(err));
ret = -EIO;
goto out;
}
err = gnutls_pkcs11_privkey_import_url(p11key, key_url, 0);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error importing PKCS#11 URL %s: %s\n"),
key_url, gnutls_strerror(err));
gnutls_pkcs11_privkey_deinit(p11key);
ret = -EIO;
goto out;
}
err = gnutls_privkey_init(&pkey);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error initialising private key structure: %s\n"),
gnutls_strerror(err));
gnutls_pkcs11_privkey_deinit(p11key);
ret = -EIO;
goto out;
}
err = gnutls_privkey_import_pkcs11(pkey, p11key, GNUTLS_PRIVKEY_IMPORT_AUTO_RELEASE);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error importing PKCS#11 key into private key structure: %s\n"),
gnutls_strerror(err));
gnutls_pkcs11_privkey_deinit(p11key);
ret = -EIO;
goto out;
}
goto match_cert;
}
#endif
/* We're loading the private key from a file. Load the file into memory
unless it's the same as the certificate and we already loaded that. */
if (!fdata.data || vpninfo->sslkey != vpninfo->cert) {
gnutls_free(fdata.data);
fdata.data = NULL;
vpn_progress(vpninfo, PRG_TRACE,
_("Using private key file %s\n"), vpninfo->sslkey);
ret = load_datum(vpninfo, &fdata, vpninfo->sslkey);
if (ret)
goto out;
}
if (vpninfo->cert_type == CERT_TYPE_TPM ||
(vpninfo->cert_type == CERT_TYPE_UNKNOWN &&
strstr((char *)fdata.data, "-----BEGIN TSS KEY BLOB-----"))) {
#ifndef HAVE_TROUSERS
vpn_progress(vpninfo, PRG_ERR,
_("This version of OpenConnect was built without TPM support\n"));
return -EINVAL;
#else
ret = load_tpm_key(vpninfo, &fdata, &pkey);
if (ret)
goto out;
goto match_cert;
#endif
}
gnutls_x509_privkey_init(&key);
/* Try PKCS#1 (and PKCS#8 without password) first. GnuTLS doesn't
support OpenSSL's old PKCS#1-based encrypted format. We should
probably check for it and give a more coherent failure mode. */
err = gnutls_x509_privkey_import(key, &fdata, GNUTLS_X509_FMT_PEM);
if (err) {
/* If that fails, try PKCS#8 */
char *pass = vpninfo->cert_password;
/* Yay, just for fun this is *different* to PKCS#12. Where we could
try an empty password there, in this case the empty-password case
has already been *tried* by gnutls_x509_privkey_import(). If we
just call gnutls_x509_privkey_import_pkcs8() with a NULL password,
it'll SEGV. You have to set the GNUTLS_PKCS_PLAIN flag if you want
to try without a password. Passing NULL evidently isn't enough of
a hint. And in GnuTLS 3.1 where that crash has been fixed, passing
NULL will cause it to return GNUTLS_E_ENCRYPTED_STRUCTURE (a new
error code) rather than GNUTLS_E_DECRYPTION_FAILED. So just pass ""
instead of NULL, and don't worry about either case. */
while ((err = gnutls_x509_privkey_import_pkcs8(key, &fdata,
GNUTLS_X509_FMT_PEM,
pass?pass:"", 0))) {
if (err != GNUTLS_E_DECRYPTION_FAILED) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load private key as PKCS#8: %s\n"),
gnutls_strerror(err));
ret = -EINVAL;
goto out;
}
vpninfo->cert_password = NULL;
if (pass) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to decrypt PKCS#8 certificate file\n"));
free(pass);
}
err = request_passphrase(vpninfo, &pass,
_("Enter PEM pass phrase:"));
if (err) {
ret = -EINVAL;
goto out;
}
}
free(pass);
vpninfo->cert_password = NULL;
}
/* Now attempt to make sure we use the *correct* certificate, to match the key */
err = gnutls_x509_privkey_get_key_id(key, 0, key_id, &key_id_size);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to get key ID: %s\n"),
gnutls_strerror(err));
goto out;
}
for (i = 0; i < (extra_certs?nr_extra_certs:1); i++) {
unsigned char cert_id[20];
size_t cert_id_size = sizeof(cert_id);
err = gnutls_x509_crt_get_key_id(extra_certs?extra_certs[i]:cert, 0, cert_id, &cert_id_size);
if (err)
continue;
if (cert_id_size == key_id_size && !memcmp(cert_id, key_id, key_id_size)) {
if (extra_certs) {
cert = extra_certs[i];
/* Move the rest of the array down */
for (; i < nr_extra_certs - 1; i++)
extra_certs[i] = extra_certs[i+1];
nr_extra_certs--;
}
goto got_key;
}
}
/* We shouldn't reach this. It means that we didn't find *any* matching cert */
vpn_progress(vpninfo, PRG_ERR,
_("No SSL certificate found to match private key\n"));
ret = -EINVAL;
goto out;
#ifdef HAVE_GNUTLS_CERTIFICATE_SET_KEY
match_cert:
if (!cert) {
/* FIXME: How do we check which cert matches the pkey?
For now we just assume that the first one in the list is the right one. */
cert = extra_certs[0];
/* Move the rest of the array down */
for (i = 0; i < nr_extra_certs - 1; i++)
extra_certs[i] = extra_certs[i+1];
nr_extra_certs--;
}
#endif
got_key:
/* Now we have both cert(s) and key, and we should be ready to go. */
check_certificate_expiry(vpninfo, cert);
get_cert_name(cert, name, sizeof(name));
vpn_progress(vpninfo, PRG_INFO, _("Using client certificate '%s'\n"),
name);
if (crl) {
err = gnutls_certificate_set_x509_crl(vpninfo->https_cred, &crl, 1);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Setting certificate recovation list failed: %s\n"),
gnutls_strerror(err));
goto out;
}
}
/* OpenSSL has problems with certificate chains — if there are
multiple certs with the same name, it doesn't necessarily
choose the _right_ one. (RT#1942)
Pick the right ones for ourselves and add them manually. */
if (nr_supporting_certs) {
/* We already got a bunch of certs from PKCS#12 file.
Remember how many need to be freed when we're done,
since we'll expand the supporting_certs array with
more from the cafile if we can. */
last_cert = supporting_certs[nr_supporting_certs-1];
certs_to_free = nr_supporting_certs;