/
http.c
1470 lines (1282 loc) · 36.3 KB
/
http.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.
* Copyright © 2008 Nick Andrew <nick@nick-andrew.net>
*
* 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 <netdb.h>
#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#include <string.h>
#include <ctype.h>
#include <pwd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include "openconnect-internal.h"
static int proxy_write(struct openconnect_info *vpninfo, int fd,
unsigned char *buf, size_t len);
static int proxy_read(struct openconnect_info *vpninfo, int fd,
unsigned char *buf, size_t len);
#define MAX_BUF_LEN 131072
#define BUF_CHUNK_SIZE 4096
struct oc_text_buf {
char *data;
int pos;
int buf_len;
int error;
};
static struct oc_text_buf *buf_alloc(void)
{
return calloc(1, sizeof(struct oc_text_buf));
}
static void buf_append(struct oc_text_buf *buf, const char *fmt, ...)
{
va_list ap;
if (!buf || buf->error)
return;
if (!buf->data) {
buf->data = malloc(BUF_CHUNK_SIZE);
if (!buf->data) {
buf->error = -ENOMEM;
return;
}
buf->buf_len = BUF_CHUNK_SIZE;
}
while (1) {
int max_len = buf->buf_len - buf->pos, ret;
va_start(ap, fmt);
ret = vsnprintf(buf->data + buf->pos, max_len, fmt, ap);
va_end(ap);
if (ret < 0) {
buf->error = -EIO;
break;
} else if (ret < max_len) {
buf->pos += ret;
break;
} else {
int new_buf_len = buf->buf_len + BUF_CHUNK_SIZE;
if (new_buf_len > MAX_BUF_LEN) {
/* probably means somebody is messing with us */
buf->error = -E2BIG;
break;
}
realloc_inplace(buf->data, new_buf_len);
if (!buf->data) {
buf->error = -ENOMEM;
break;
}
buf->buf_len = new_buf_len;
}
}
}
static int buf_error(struct oc_text_buf *buf)
{
return buf ? buf->error : -ENOMEM;
}
static int buf_free(struct oc_text_buf *buf)
{
int error = buf_error(buf);
if (buf) {
if (buf->data)
free(buf->data);
free(buf);
}
return error;
}
/*
* We didn't really want to have to do this for ourselves -- one might have
* thought that it would be available in a library somewhere. But neither
* cURL nor Neon have reliable cross-platform ways of either using a cert
* from the TPM, or just reading from / writing to a transport which is
* provided by their caller.
*/
static int http_add_cookie(struct openconnect_info *vpninfo,
const char *option, const char *value)
{
struct vpn_option *new, **this;
if (*value) {
new = malloc(sizeof(*new));
if (!new) {
vpn_progress(vpninfo, PRG_ERR,
_("No memory for allocating cookies\n"));
return -ENOMEM;
}
new->next = NULL;
new->option = strdup(option);
new->value = strdup(value);
if (!new->option || !new->value) {
free(new->option);
free(new->value);
free(new);
return -ENOMEM;
}
} else {
/* Kill cookie; don't replace it */
new = NULL;
}
for (this = &vpninfo->cookies; *this; this = &(*this)->next) {
if (!strcmp(option, (*this)->option)) {
/* Replace existing cookie */
if (new)
new->next = (*this)->next;
else
new = (*this)->next;
free((*this)->option);
free((*this)->value);
free(*this);
*this = new;
break;
}
}
if (new && !*this) {
*this = new;
new->next = NULL;
}
return 0;
}
#define BODY_HTTP10 -1
#define BODY_CHUNKED -2
static int process_http_response(struct openconnect_info *vpninfo, int *result,
int (*header_cb)(struct openconnect_info *, char *, char *),
char **body_ret)
{
char buf[MAX_BUF_LEN];
char *body = NULL;
int bodylen = BODY_HTTP10;
int done = 0;
int closeconn = 0;
int i;
cont:
if (openconnect_SSL_gets(vpninfo, buf, sizeof(buf)) < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Error fetching HTTPS response\n"));
return -EINVAL;
}
if (!strncmp(buf, "HTTP/1.0 ", 9))
closeconn = 1;
if ((!closeconn && strncmp(buf, "HTTP/1.1 ", 9)) || !(*result = atoi(buf+9))) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to parse HTTP response '%s'\n"), buf);
return -EINVAL;
}
vpn_progress(vpninfo, (*result==200)?PRG_TRACE:PRG_INFO,
_("Got HTTP response: %s\n"), buf);
/* Eat headers... */
while ((i = openconnect_SSL_gets(vpninfo, buf, sizeof(buf)))) {
char *colon;
if (i < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Error processing HTTP response\n"));
return -EINVAL;
}
colon = strchr(buf, ':');
if (!colon) {
vpn_progress(vpninfo, PRG_ERR,
_("Ignoring unknown HTTP response line '%s'\n"), buf);
continue;
}
*(colon++) = 0;
if (*colon == ' ')
colon++;
/* Handle Set-Cookie first so that we can avoid printing the
webvpn cookie in the verbose debug output */
if (!strcasecmp(buf, "Set-Cookie")) {
char *semicolon = strchr(colon, ';');
const char *print_equals;
char *equals = strchr(colon, '=');
int ret;
if (semicolon)
*semicolon = 0;
if (!equals) {
vpn_progress(vpninfo, PRG_ERR,
_("Invalid cookie offered: %s\n"), buf);
return -EINVAL;
}
*(equals++) = 0;
print_equals = equals;
/* Don't print the webvpn cookie unless it's empty; we don't
want people posting it in public with debugging output */
if (!strcmp(colon, "webvpn") && *equals)
print_equals = _("<elided>");
vpn_progress(vpninfo, PRG_TRACE, "%s: %s=%s%s%s\n",
buf, colon, print_equals, semicolon?";":"",
semicolon?(semicolon+1):"");
/* The server tends to ask for the username and password as
usual, even if we've already failed because it didn't like
our cert. Thankfully it does give us this hint... */
if (!strcmp(colon, "ClientCertAuthFailed"))
vpn_progress(vpninfo, PRG_ERR,
_("SSL certificate authentication failed\n"));
ret = http_add_cookie(vpninfo, colon, equals);
if (ret)
return ret;
} else {
vpn_progress(vpninfo, PRG_TRACE, "%s: %s\n", buf, colon);
}
if (!strcasecmp(buf, "Connection")) {
if (!strcasecmp(colon, "Close"))
closeconn = 1;
#if 0
/* This might seem reasonable, but in fact it breaks
certificate authentication with some servers. If
they give an HTTP/1.0 response, even if they
explicitly give a Connection: Keep-Alive header,
just close the connection. */
else if (!strcasecmp(colon, "Keep-Alive"))
closeconn = 0;
#endif
}
if (!strcasecmp(buf, "Location")) {
vpninfo->redirect_url = strdup(colon);
if (!vpninfo->redirect_url)
return -ENOMEM;
}
if (!strcasecmp(buf, "Content-Length")) {
bodylen = atoi(colon);
if (bodylen < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Response body has negative size (%d)\n"),
bodylen);
return -EINVAL;
}
}
if (!strcasecmp(buf, "Transfer-Encoding")) {
if (!strcasecmp(colon, "chunked"))
bodylen = BODY_CHUNKED;
else {
vpn_progress(vpninfo, PRG_ERR,
_("Unknown Transfer-Encoding: %s\n"),
colon);
return -EINVAL;
}
}
if (header_cb && !strncmp(buf, "X-", 2))
header_cb(vpninfo, buf, colon);
}
/* Handle 'HTTP/1.1 100 Continue'. Not that we should ever see it */
if (*result == 100)
goto cont;
/* Now the body, if there is one */
vpn_progress(vpninfo, PRG_TRACE, _("HTTP body %s (%d)\n"),
bodylen==BODY_HTTP10?"http 1.0" :
bodylen==BODY_CHUNKED?"chunked" : "length: ",
bodylen);
/* If we were given Content-Length, it's nice and easy... */
if (bodylen > 0) {
body = malloc(bodylen + 1);
if (!body)
return -ENOMEM;
while (done < bodylen) {
i = openconnect_SSL_read(vpninfo, body + done, bodylen - done);
if (i < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Error reading HTTP response body\n"));
free(body);
return -EINVAL;
}
done += i;
}
} else if (bodylen == BODY_CHUNKED) {
/* ... else, chunked */
while ((i = openconnect_SSL_gets(vpninfo, buf, sizeof(buf)))) {
int chunklen, lastchunk = 0;
if (i < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Error fetching chunk header\n"));
return i;
}
chunklen = strtol(buf, NULL, 16);
if (!chunklen) {
lastchunk = 1;
goto skip;
}
realloc_inplace(body, done + chunklen + 1);
if (!body)
return -ENOMEM;
while (chunklen) {
i = openconnect_SSL_read(vpninfo, body + done, chunklen);
if (i < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Error reading HTTP response body\n"));
free(body);
return -EINVAL;
}
chunklen -= i;
done += i;
}
skip:
if ((i = openconnect_SSL_gets(vpninfo, buf, sizeof(buf)))) {
if (i < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Error fetching HTTP response body\n"));
} else {
vpn_progress(vpninfo, PRG_ERR,
_("Error in chunked decoding. Expected '', got: '%s'"),
buf);
}
free(body);
return -EINVAL;
}
if (lastchunk)
break;
}
} else if (bodylen == BODY_HTTP10) {
if (!closeconn) {
vpn_progress(vpninfo, PRG_ERR,
_("Cannot receive HTTP 1.0 body without closing connection\n"));
openconnect_close_https(vpninfo, 0);
return -EINVAL;
}
/* HTTP 1.0 response. Just eat all we can in 16KiB chunks */
while (1) {
realloc_inplace(body, done + 16384);
if (!body)
return -ENOMEM;
i = openconnect_SSL_read(vpninfo, body + done, 16384);
if (i > 0) {
/* Got more data */
done += i;
} else if (i < 0) {
/* Error */
free(body);
return i;
} else {
/* Connection closed. Reduce allocation to just what we need */
realloc_inplace(body, done + 1);
if (!body)
return -ENOMEM;
break;
}
}
}
if (closeconn || vpninfo->no_http_keepalive)
openconnect_close_https(vpninfo, 0);
if (body)
body[done] = 0;
*body_ret = body;
return done;
}
static void add_common_headers(struct openconnect_info *vpninfo, struct oc_text_buf *buf)
{
struct vpn_option *opt;
buf_append(buf, "Host: %s\r\n", vpninfo->hostname);
buf_append(buf, "User-Agent: %s\r\n", vpninfo->useragent);
buf_append(buf, "Accept: */*\r\n");
buf_append(buf, "Accept-Encoding: identity\r\n");
if (vpninfo->cookies) {
buf_append(buf, "Cookie: ");
for (opt = vpninfo->cookies; opt; opt = opt->next)
buf_append(buf, "%s=%s%s", opt->option,
opt->value, opt->next ? "; " : "\r\n");
}
buf_append(buf, "X-Transcend-Version: 1\r\n");
buf_append(buf, "X-Aggregate-Auth: 1\r\n");
buf_append(buf, "X-AnyConnect-Platform: %s\r\n", vpninfo->platname);
}
static int fetch_config(struct openconnect_info *vpninfo, char *fu, char *bu,
char *server_sha1)
{
struct oc_text_buf *buf;
char *config_buf = NULL;
int result, buflen;
unsigned char local_sha1_bin[SHA1_SIZE];
char local_sha1_ascii[(SHA1_SIZE * 2)+1];
int i;
if (openconnect_open_https(vpninfo)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open HTTPS connection to %s\n"),
vpninfo->hostname);
return -EINVAL;
}
buf = buf_alloc();
buf_append(buf, "GET %s%s HTTP/1.1\r\n", fu, bu);
add_common_headers(vpninfo, buf);
buf_append(buf, "\r\n");
if (buf_error(buf))
return buf_free(buf);
if (openconnect_SSL_write(vpninfo, buf->data, buf->pos) != buf->pos) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to send GET request for new config\n"));
buf_free(buf);
return -EIO;
}
buf_free(buf);
buflen = process_http_response(vpninfo, &result, NULL, &config_buf);
if (buflen < 0) {
/* We'll already have complained about whatever offended us */
return -EINVAL;
}
if (result != 200) {
free(config_buf);
return -EINVAL;
}
openconnect_sha1(local_sha1_bin, config_buf, buflen);
for (i = 0; i < SHA1_SIZE; i++)
sprintf(&local_sha1_ascii[i*2], "%02x", local_sha1_bin[i]);
if (strcasecmp(server_sha1, local_sha1_ascii)) {
vpn_progress(vpninfo, PRG_ERR,
_("Downloaded config file did not match intended SHA1\n"));
free(config_buf);
return -EINVAL;
}
result = vpninfo->write_new_config(vpninfo->cbdata, config_buf, buflen);
free(config_buf);
return result;
}
static int run_csd_script(struct openconnect_info *vpninfo, char *buf, int buflen)
{
char fname[16];
int fd, ret;
if (!vpninfo->uid_csd_given && !vpninfo->csd_wrapper) {
vpn_progress(vpninfo, PRG_ERR,
_("Error: Server asked us to download and run a 'Cisco Secure Desktop' trojan.\n"
"This facility is disabled by default for security reasons, so you may wish to enable it."));
return -EPERM;
}
#ifndef __linux__
vpn_progress(vpninfo, PRG_INFO,
_("Trying to run Linux CSD trojan script."));
#endif
sprintf(fname, "/tmp/csdXXXXXX");
fd = mkstemp(fname);
if (fd < 0) {
int err = -errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open temporary CSD script file: %s\n"),
strerror(errno));
return err;
}
ret = proxy_write(vpninfo, fd, (void *)buf, buflen);
if (ret) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to write temporary CSD script file: %s\n"),
strerror(-ret));
return ret;
}
fchmod(fd, 0755);
close(fd);
if (!fork()) {
char scertbuf[MD5_SIZE * 2 + 1];
char ccertbuf[MD5_SIZE * 2 + 1];
char *csd_argv[32];
int i = 0;
if (vpninfo->uid_csd_given && vpninfo->uid_csd != getuid()) {
struct passwd *pw;
if (setuid(vpninfo->uid_csd)) {
fprintf(stderr, _("Failed to set uid %ld\n"),
(long)vpninfo->uid_csd);
exit(1);
}
if (!(pw = getpwuid(vpninfo->uid_csd))) {
fprintf(stderr, _("Invalid user uid=%ld\n"),
(long)vpninfo->uid_csd);
exit(1);
}
setenv("HOME", pw->pw_dir, 1);
if (chdir(pw->pw_dir)) {
fprintf(stderr, _("Failed to change to CSD home directory '%s': %s\n"),
pw->pw_dir, strerror(errno));
exit(1);
}
}
if (getuid() == 0 && !vpninfo->csd_wrapper) {
fprintf(stderr, _("Warning: you are running insecure "
"CSD code with root privileges\n"
"\t Use command line option \"--csd-user\"\n"));
}
if (vpninfo->uid_csd_given == 2) {
/* The NM tool really needs not to get spurious output
on stdout, which the CSD trojan spews. */
dup2(2, 1);
}
if (vpninfo->csd_wrapper)
csd_argv[i++] = vpninfo->csd_wrapper;
csd_argv[i++] = fname;
csd_argv[i++]= (char *)"-ticket";
if (asprintf(&csd_argv[i++], "\"%s\"", vpninfo->csd_ticket) == -1)
goto out;
csd_argv[i++]= (char *)"-stub";
csd_argv[i++]= (char *)"\"0\"";
csd_argv[i++]= (char *)"-group";
if (asprintf(&csd_argv[i++], "\"%s\"", vpninfo->authgroup?:"") == -1)
goto out;
openconnect_local_cert_md5(vpninfo, ccertbuf);
scertbuf[0] = 0;
get_cert_md5_fingerprint(vpninfo, vpninfo->peer_cert, scertbuf);
csd_argv[i++]= (char *)"-certhash";
if (asprintf(&csd_argv[i++], "\"%s:%s\"", scertbuf, ccertbuf) == -1)
goto out;
csd_argv[i++]= (char *)"-url";
if (asprintf(&csd_argv[i++], "\"https://%s%s\"", vpninfo->hostname, vpninfo->csd_starturl) == -1)
goto out;
csd_argv[i++]= (char *)"-langselen";
csd_argv[i++] = NULL;
if (setenv("CSD_TOKEN", vpninfo->csd_token, 1))
goto out;
if (setenv("CSD_HOSTNAME", vpninfo->hostname, 1))
goto out;
execv(csd_argv[0], csd_argv);
out:
vpn_progress(vpninfo, PRG_ERR,
_("Failed to exec CSD script %s\n"), csd_argv[0]);
exit(1);
}
free(vpninfo->csd_stuburl);
vpninfo->csd_stuburl = NULL;
free(vpninfo->urlpath);
vpninfo->urlpath = strdup(vpninfo->csd_waiturl +
(vpninfo->csd_waiturl[0] == '/' ? 1 : 0));
free(vpninfo->csd_waiturl);
vpninfo->csd_waiturl = NULL;
vpninfo->csd_scriptname = strdup(fname);
http_add_cookie(vpninfo, "sdesktop", vpninfo->csd_token);
return 0;
}
int internal_parse_url(char *url, char **res_proto, char **res_host,
int *res_port, char **res_path, int default_port)
{
char *proto = url;
char *host, *path, *port_str;
int port;
host = strstr(url, "://");
if (host) {
*host = 0;
host += 3;
if (!strcasecmp(proto, "https"))
port = 443;
else if (!strcasecmp(proto, "http"))
port = 80;
else if (!strcasecmp(proto, "socks") ||
!strcasecmp(proto, "socks4") ||
!strcasecmp(proto, "socks5"))
port = 1080;
else
return -EPROTONOSUPPORT;
} else {
if (default_port) {
proto = NULL;
port = default_port;
host = url;
} else
return -EINVAL;
}
path = strchr(host, '/');
if (path)
*(path++) = 0;
port_str = strrchr(host, ':');
if (port_str) {
char *end;
int new_port = strtol(port_str + 1, &end, 10);
if (!*end) {
*port_str = 0;
port = new_port;
}
}
if (res_proto)
*res_proto = proto ? strdup(proto) : NULL;
if (res_host)
*res_host = strdup(host);
if (res_port)
*res_port = port;
if (res_path)
*res_path = (path && *path) ? strdup(path) : NULL;
/* Undo the damage we did to the original string */
if (port_str)
*(port_str) = ':';
if (path)
*(path - 1) = '/';
if (proto)
*(host - 3) = ':';
return 0;
}
static void clear_cookies(struct openconnect_info *vpninfo)
{
struct vpn_option *opt, *next;
for (opt = vpninfo->cookies; opt; opt = next) {
next = opt->next;
free(opt->option);
free(opt->value);
free(opt);
}
vpninfo->cookies = NULL;
}
/* Return value:
* < 0, on error
* = 0, on success (go ahead and retry with the latest vpninfo->{hostname,urlpath,port,...})
*/
static int handle_redirect(struct openconnect_info *vpninfo)
{
vpninfo->redirect_type = REDIR_TYPE_LOCAL;
if (!strncmp(vpninfo->redirect_url, "https://", 8)) {
/* New host. Tear down the existing connection and make a new one */
char *host;
int port;
int ret;
free(vpninfo->urlpath);
vpninfo->urlpath = NULL;
ret = internal_parse_url(vpninfo->redirect_url, NULL, &host, &port, &vpninfo->urlpath, 0);
if (ret) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to parse redirected URL '%s': %s\n"),
vpninfo->redirect_url, strerror(-ret));
free(vpninfo->redirect_url);
vpninfo->redirect_url = NULL;
return ret;
}
if (strcasecmp(vpninfo->hostname, host) || port != vpninfo->port) {
free(vpninfo->unique_hostname);
vpninfo->unique_hostname = NULL;
free(vpninfo->hostname);
vpninfo->hostname = host;
vpninfo->port = port;
/* Kill the existing connection, and a new one will happen */
free(vpninfo->peer_addr);
vpninfo->peer_addr = NULL;
openconnect_close_https(vpninfo, 0);
clear_cookies(vpninfo);
vpninfo->redirect_type = REDIR_TYPE_NEWHOST;
} else
free(host);
free(vpninfo->redirect_url);
vpninfo->redirect_url = NULL;
return 0;
} else if (strstr(vpninfo->redirect_url, "://")) {
vpn_progress(vpninfo, PRG_ERR,
_("Cannot follow redirection to non-https URL '%s'\n"),
vpninfo->redirect_url);
free(vpninfo->redirect_url);
vpninfo->redirect_url = NULL;
return -EINVAL;
} else if (vpninfo->redirect_url[0] == '/') {
/* Absolute redirect within same host */
free(vpninfo->urlpath);
vpninfo->urlpath = strdup(vpninfo->redirect_url + 1);
free(vpninfo->redirect_url);
vpninfo->redirect_url = NULL;
return 0;
} else {
char *lastslash = NULL;
if (vpninfo->urlpath)
lastslash = strrchr(vpninfo->urlpath, '/');
if (!lastslash) {
free(vpninfo->urlpath);
vpninfo->urlpath = vpninfo->redirect_url;
vpninfo->redirect_url = NULL;
} else {
char *oldurl = vpninfo->urlpath;
*lastslash = 0;
vpninfo->urlpath = NULL;
if (asprintf(&vpninfo->urlpath, "%s/%s",
oldurl, vpninfo->redirect_url) == -1) {
int err = -errno;
vpn_progress(vpninfo, PRG_ERR,
_("Allocating new path for relative redirect failed: %s\n"),
strerror(-err));
return err;
}
free(oldurl);
free(vpninfo->redirect_url);
vpninfo->redirect_url = NULL;
}
return 0;
}
}
/* Inputs:
* method: GET or POST
* vpninfo->hostname: Host DNS name
* vpninfo->port: TCP port, typically 443
* vpninfo->urlpath: Relative path, e.g. /+webvpn+/foo.html
* request_body_type: Content type for a POST (e.g. text/html). Can be NULL.
* request_body: POST content
* form_buf: Callee-allocated buffer for server content
*
* Return value:
* < 0, on error
* >=0, on success, indicating the length of the data in *form_buf
*/
static int do_https_request(struct openconnect_info *vpninfo, const char *method,
const char *request_body_type, const char *request_body,
char **form_buf, int fetch_redirect)
{
struct oc_text_buf *buf;
int result, buflen;
retry:
vpninfo->redirect_type = REDIR_TYPE_NONE;
if (*form_buf) {
free(*form_buf);
*form_buf = NULL;
}
if (openconnect_open_https(vpninfo)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open HTTPS connection to %s\n"),
vpninfo->hostname);
return -EINVAL;
}
/*
* It would be nice to use cURL for this, but we really need to guarantee
* that we'll be using OpenSSL (for the TPM stuff), and it doesn't seem
* to have any way to let us provide our own socket read/write functions.
* We can only provide a socket _open_ function. Which would require having
* a socketpair() and servicing the "other" end of it.
*
* So we process the HTTP for ourselves...
*/
buf = buf_alloc();
buf_append(buf, "%s /%s HTTP/1.1\r\n", method, vpninfo->urlpath ?: "");
add_common_headers(vpninfo, buf);
if (request_body_type) {
buf_append(buf, "Content-Type: %s\r\n", request_body_type);
buf_append(buf, "Content-Length: %zd\r\n", strlen(request_body));
}
buf_append(buf, "\r\n");
if (request_body_type)
buf_append(buf, "%s", request_body);
if (vpninfo->port == 443)
vpn_progress(vpninfo, PRG_INFO, "%s https://%s/%s\n",
method, vpninfo->hostname,
vpninfo->urlpath ?: "");
else
vpn_progress(vpninfo, PRG_INFO, "%s https://%s:%d/%s\n",
method, vpninfo->hostname, vpninfo->port,
vpninfo->urlpath ?: "");
if (buf_error(buf))
return buf_free(buf);
result = openconnect_SSL_write(vpninfo, buf->data, buf->pos);
buf_free(buf);
if (result < 0)
return result;
buflen = process_http_response(vpninfo, &result, NULL, form_buf);
if (buflen < 0) {
/* We'll already have complained about whatever offended us */
return buflen;
}
if (result != 200 && vpninfo->redirect_url) {
result = handle_redirect(vpninfo);
if (result == 0) {
if (!fetch_redirect)
return 0;
goto retry;
}
goto out;
}
if (!*form_buf || result != 200) {
vpn_progress(vpninfo, PRG_ERR,
_("Unexpected %d result from server\n"),
result);
result = -EINVAL;
goto out;
}
return buflen;
out:
free(*form_buf);
*form_buf = NULL;
return result;
}
/* Return value:
* < 0, if the data is unrecognized
* = 0, if the page contains an XML document
* = 1, if the page is a wait/refresh HTML page
*/
static int check_response_type(struct openconnect_info *vpninfo, char *form_buf)
{
if (strncmp(form_buf, "<?xml", 5)) {
/* Not XML? Perhaps it's HTML with a refresh... */
if (strcasestr(form_buf, "http-equiv=\"refresh\""))
return 1;
vpn_progress(vpninfo, PRG_ERR,
_("Unknown response from server\n"));
return -EINVAL;
}
return 0;
}
/* Return value:
* < 0, on error
* > 0, no cookie (user cancel)
* = 0, obtained cookie
*/
int openconnect_obtain_cookie(struct openconnect_info *vpninfo)
{
struct vpn_option *opt;
char *form_buf = NULL;
struct oc_auth_form *form = NULL;
int result, buflen, tries;
char request_body[2048];
const char *request_body_type = "application/x-www-form-urlencoded";
const char *method = "POST";
int xmlpost = 1;
/* Step 1: Unlock software token (if applicable) */
if (vpninfo->use_stoken) {
result = prepare_stoken(vpninfo);
if (result)
return result;
}
/*
* Step 2: Probe for XML POST compatibility
*
* This can get stuck in a redirect loop, so give up after any of:
*
* a) HTTP error (e.g. 400 Bad Request)
* b) Same-host redirect (e.g. Location: /foo/bar)
* c) Three redirects without seeing a plausible login form
*/
result = xmlpost_initial_req(vpninfo, request_body, sizeof(request_body));
if (result < 0)
return result;
for (tries = 0; ; tries++) {
if (tries == 3) {
fail:
if (xmlpost) {
/* Try without XML POST this time... */
tries = 0;
xmlpost = 0;
request_body_type = NULL;
request_body[0] = 0;
method = "GET";
} else {
return -EIO;
}
}
buflen = do_https_request(vpninfo, method, request_body_type, request_body,
&form_buf, 0);
if (buflen == -EINVAL)
goto fail;
if (buflen < 0)
return buflen;
/* XML POST does not allow local redirects, but GET does. */
if (xmlpost && vpninfo->redirect_type == REDIR_TYPE_LOCAL)
goto fail;
else if (vpninfo->redirect_type != REDIR_TYPE_NONE)
continue;
result = parse_xml_response(vpninfo, form_buf, &form);
if (result < 0)
goto fail;
if (form->action) {
vpninfo->redirect_url = strdup(form->action);
handle_redirect(vpninfo);
}
break;
}
if (xmlpost)
vpn_progress(vpninfo, PRG_INFO, _("XML POST enabled\n"));