forked from rdesktop/rdesktop
-
Notifications
You must be signed in to change notification settings - Fork 0
/
utils.c
1060 lines (885 loc) · 22.9 KB
/
utils.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
/* -*- c-basic-offset: 8 -*-
rdesktop: A Remote Desktop Protocol client.
Generic utility functions
Copyright 2013-2019 Henrik Andersson <hean01@cendio.se> for Cendio AB
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <errno.h>
#include <iconv.h>
#include <stdarg.h>
#include <assert.h>
#include "rdesktop.h"
#include "utils.h"
extern char g_codepage[16];
static RD_BOOL g_iconv_works = True;
uint32
utils_djb2_hash(const char *str)
{
uint8 c;
uint8 *pstr;
uint32 hash = 5381;
pstr = (uint8 *) str;
while ((c = *pstr++))
{
hash = ((hash << 5) + hash) + c;
}
return hash;
}
char *
utils_string_escape(const char *str)
{
const char *p;
char *pe, *e, esc[4];
size_t es;
int cnt;
/* count indices */
cnt = 0;
p = str;
while (*(p++) != '\0')
if ((unsigned char) *p < 32 || *p == '%')
cnt++;
/* if no characters needs escaping return copy of str */
if (cnt == 0)
return strdup(str);
/* allocate new mem for result */
es = strlen(str) + (cnt * 3) + 1;
pe = e = xmalloc(es);
memset(e, 0, es);
p = str;
while (*p != '\0')
{
if ((unsigned char) *p < 32 || *p == '%')
{
snprintf(esc, 4, "%%%02X", *p);
memcpy(pe, esc, 3);
pe += 3;
}
else
{
*pe = *p;
pe++;
}
p++;
}
return e;
}
char *
utils_string_unescape(const char *str)
{
char *ns, *ps, *pd;
unsigned char c;
ns = xmalloc(strlen(str) + 1);
memcpy(ns, str, strlen(str) + 1);
ps = pd = ns;
while (*ps != '\0')
{
/* check if found escaped character */
if (ps[0] == '%')
{
if (sscanf(ps, "%%%2hhX", &c) == 1)
{
pd[0] = (char) c;
ps += 3;
pd++;
continue;
}
}
/* just copy over the char */
*pd = *ps;
ps++;
pd++;
}
pd[0] = '\0';
return ns;
}
int
utils_mkdir_safe(const char *path, int mask)
{
int res = 0;
struct stat st;
res = stat(path, &st);
if (res == -1)
return mkdir(path, mask);
if (!S_ISDIR(st.st_mode))
{
errno = EEXIST;
return -1;
}
return 0;
}
int
utils_mkdir_p(const char *path, int mask)
{
int res;
char *ptok;
char pt[PATH_MAX];
char bp[PATH_MAX];
if (!path || strlen(path) == 0)
{
errno = EINVAL;
return -1;
}
if (strlen(path) > PATH_MAX)
{
errno = E2BIG;
return -1;
}
res = 0;
pt[0] = bp[0] = '\0';
strcpy(bp, path);
ptok = strtok(bp, "/");
if (ptok == NULL)
return utils_mkdir_safe(path, mask);
do
{
if (ptok != bp)
strcat(pt, "/");
strcat(pt, ptok);
res = utils_mkdir_safe(pt, mask);
if (res != 0)
return res;
}
while ((ptok = strtok(NULL, "/")) != NULL);
return 0;
}
/* Convert from system locale string to UTF-8 */
int
utils_locale_to_utf8(const char *src, size_t is, char *dest, size_t os)
{
static iconv_t *iconv_h = (iconv_t) - 1;
if (strncmp(g_codepage, "UTF-8", strlen("UTF-8")) == 0)
goto pass_trough_as_is;
if (g_iconv_works == False)
goto pass_trough_as_is;
/* if not already initialize */
if (iconv_h == (iconv_t) - 1)
{
if ((iconv_h = iconv_open("UTF-8", g_codepage)) == (iconv_t) - 1)
{
logger(Core, Warning,
"utils_string_to_utf8(), iconv_open[%s -> %s] fail %p", g_codepage,
"UTF-8", iconv_h);
g_iconv_works = False;
goto pass_trough_as_is;
}
}
/* convert string */
if (iconv(iconv_h, (char **) &src, &is, &dest, &os) == (size_t) - 1)
{
iconv_close(iconv_h);
iconv_h = (iconv_t) - 1;
logger(Core, Warning, "utils_string_to_utf8, iconv(1) fail, errno %d", errno);
g_iconv_works = False;
goto pass_trough_as_is;
}
/* Out couldn't hold the entire conversion */
if (is != 0)
return -1;
pass_trough_as_is:
/* can dest hold strcpy of src */
if (os < (strlen(src) + 1))
return -1;
memcpy(dest, src, strlen(src) + 1);
return 0;
}
void
utils_calculate_dpi_scale_factors(uint32 width, uint32 height, uint32 dpi,
uint32 * physwidth, uint32 * physheight,
uint32 * desktopscale, uint32 * devicescale)
{
*physwidth = *physheight = *desktopscale = *devicescale = 0;
if (dpi > 0)
{
*physwidth = width * 254 / (dpi * 10);
*physheight = height * 254 / (dpi * 10);
/* the spec calls this out as being valid for range
100-500 but I doubt the upper range is accurate */
*desktopscale = dpi < 96 ? 100 : (dpi * 100 + 48) / 96;
/* the only allowed values for device scale factor are
100, 140, and 180. */
*devicescale = dpi < 134 ? 100 : (dpi < 173 ? 140 : 180);
}
}
void
utils_apply_session_size_limitations(uint32 * width, uint32 * height)
{
/* width MUST be even number */
*width -= (*width) % 2;
if (*width > 8192)
*width = 8192;
else if (*width < 200)
*width = 200;
if (*height > 8192)
*height = 8192;
else if (*height < 200)
*height = 200;
}
#define MAX_CHOICES 10
const char *
util_dialog_choice(const char *message, ...)
{
int i;
va_list ap;
char *p;
const char *choice;
char response[512];
const char *choices[MAX_CHOICES] = {0};
/* gather choices into array */
va_start(ap, message);
for (i = 0; i < MAX_CHOICES; i++)
{
choices[i] = va_arg(ap, const char *);
if (choices[i] == NULL)
break;
}
va_end(ap);
choice = NULL;
while (choice == NULL)
{
/* display message */
fprintf(stderr,"\n%s", message);
/* read input */
if (fgets(response, sizeof(response), stdin) != NULL)
{
/* strip final newline */
p = strchr(response, '\n');
if (p != NULL)
*p = 0;
for (i = 0; i < MAX_CHOICES; i++)
{
if (choices[i] == NULL)
break;
if (strcmp(response, choices[i]) == 0)
{
choice = choices[i];
break;
}
}
}
else
{
logger(Core, Error, "Failed to read response from stdin");
break;
}
}
return choice;
}
/*
* component logging
*
*/
static char *level[] = {
"debug",
"verbose", /* Verbose message for end user, no prefixed lines */
"warning",
"error",
"notice" /* Normal messages for end user, no prefixed lines */
};
static char *subject[] = {
"UI",
"Keyboard",
"Clipboard",
"Sound",
"Protocol",
"Graphics",
"Core",
"SmartCard",
"Disk"
};
static log_level_t _logger_level = Warning;
#define DEFAULT_LOGGER_SUBJECTS (1 << Core)
#define ALL_LOGGER_SUBJECTS \
(1 << GUI) \
| (1 << Keyboard) \
| (1 << Clipboard) \
| (1 << Sound) \
| (1 << Protocol) \
| (1 << Graphics) \
| (1 << Core) \
| (1 << SmartCard) \
| (1 << Disk)
static int _logger_subjects = DEFAULT_LOGGER_SUBJECTS;
void
logger(log_subject_t s, log_level_t lvl, char *format, ...)
{
va_list ap;
char buf[1024];
// Do not log if message is below global log level
if (_logger_level > lvl)
return;
// Skip debug logging for non specified subjects
if (lvl < Verbose && !(_logger_subjects & (1 << s)))
return;
va_start(ap, format);
vsnprintf(buf, sizeof(buf), format, ap);
// Notice and Verbose messages goes without prefix
if (lvl == Notice || lvl == Verbose)
fprintf(stdout, "%s\n", buf);
else
fprintf(stderr, "%s(%s): %s\n", subject[s], level[lvl], buf);
fflush(stdout);
va_end(ap);
}
void
logger_set_verbose(int verbose)
{
if (_logger_level < Verbose)
return;
if (verbose)
_logger_level = Verbose;
else
_logger_level = Warning;
}
void
logger_set_subjects(char *subjects)
{
int clear;
int bit;
char *pcs;
char *token;
if (!subjects || !strlen(subjects))
return;
pcs = strdup(subjects);
token = strtok(pcs, ",");
if (token == NULL)
{
free(pcs);
return;
}
_logger_subjects = 0;
do
{
if (token == NULL)
break;
bit = 0;
clear = (token[0] == '-') ? 1 : 0;
if (clear == 1)
token++;
if (strcmp(token, "All") == 0)
_logger_subjects |= ALL_LOGGER_SUBJECTS;
else if (strcmp(token, "UI") == 0)
bit = (1 << GUI);
else if (strcmp(token, "Keyboard") == 0)
bit = (1 << Keyboard);
else if (strcmp(token, "Clipboard") == 0)
bit = (1 << Clipboard);
else if (strcmp(token, "Sound") == 0)
bit = (1 << Sound);
else if (strcmp(token, "Protocol") == 0)
bit = (1 << Protocol);
else if (strcmp(token, "Graphics") == 0)
bit = (1 << Graphics);
else if (strcmp(token, "Core") == 0)
bit = (1 << Core);
else if (strcmp(token, "SmartCard") == 0)
bit = (1 << SmartCard);
else if (strcmp(token, "Disk") == 0)
bit = (1 << Disk);
else
continue;
// set or clear logger subject bit
if (clear)
_logger_subjects &= ~bit;
else
_logger_subjects |= bit;
}
while ((token = strtok(NULL, ",")) != NULL);
_logger_level = Debug;
free(pcs);
}
static size_t
_utils_data_to_hex(uint8 *data, size_t len, char *out, size_t size)
{
size_t i;
char hex[4];
assert((len * 2) < size);
memset(out, 0, size);
for (i = 0; i < len; i++)
{
snprintf(hex, sizeof(hex), "%.2x", data[i]);
strcat(out, hex);
}
return (len*2);
}
static size_t
_utils_oid_to_string(const char *oid, char *out, size_t size)
{
memset(out, 0, size);
if (strcmp(oid, "0.9.2342.19200300.100.1.25") == 0) {
snprintf(out, size, "%s", "DC");
}
else if (strcmp(oid, "2.5.4.3") == 0) {
snprintf(out, size, "%s", "CN");
}
else if (strcmp(oid, "1.2.840.113549.1.1.13") == 0)
{
snprintf(out, size, "%s", "sha512WithRSAEncryption");
}
else
{
snprintf(out, size, "%s", oid);
}
return strlen(out);
}
static int
_utils_dn_to_string(gnutls_x509_dn_t dn, RD_BOOL exclude_oid,
char *out, size_t size)
{
int i, j;
char buf[128] = {0};
char name[64] = {0};
char result[1024] = {0};
size_t left;
gnutls_x509_ava_st ava;
left = sizeof(result);
for (j = 0; j < 100; j++)
{
for (i = 0; i < 100; i++)
{
if (gnutls_x509_dn_get_rdn_ava(dn, j, i, &ava) != 0)
{
break;
}
if (exclude_oid)
{
snprintf(buf, sizeof(buf), "%.*s", ava.value.size, ava.value.data);
strncat(result, buf, left);
left -= strlen(buf);
}
else
{
_utils_oid_to_string((char *)ava.oid.data, name, sizeof(name));
snprintf(buf, sizeof(buf), "%s%s=%.*s",
(j > 0)?", ":"", name, ava.value.size, ava.value.data);
strncat(result, buf, left);
left -= strlen(buf);
}
}
if (i == 0)
{
break;
}
}
snprintf(out, size, "%s", result);
return 0;
}
static void
_utils_cert_get_info(gnutls_x509_crt_t cert, char *out, size_t size)
{
char buf[128];
size_t buf_size;
char digest[128];
gnutls_x509_dn_t dn;
time_t expire_ts, activated_ts;
char subject[256];
char issuer[256];
char valid_from[256];
char valid_to[256];
char sha1[256];
char sha256[256];
/* get subject */
gnutls_x509_crt_get_subject(cert, &dn);
if (_utils_dn_to_string(dn, False, buf, sizeof(buf)) == 0)
{
snprintf(subject, sizeof(subject), " Subject: %s", buf);
}
/* get issuer */
gnutls_x509_crt_get_issuer(cert, &dn);
if (_utils_dn_to_string(dn, False, buf, sizeof(buf)) == 0)
{
snprintf(issuer, sizeof(issuer), " Issuer: %s", buf);
}
/* get activation / expiration time */
activated_ts = gnutls_x509_crt_get_activation_time(cert);
snprintf(valid_from, sizeof(valid_from), " Valid From: %s", ctime(&activated_ts));
expire_ts = gnutls_x509_crt_get_expiration_time(cert);
snprintf(valid_to, sizeof(valid_to), " To: %s", ctime(&expire_ts));
/* get sha1 / sha256 fingerprint */
buf_size = sizeof(buf);
gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA1, buf, &buf_size);
_utils_data_to_hex((uint8 *)buf, buf_size, digest, sizeof(digest));
snprintf(sha1, sizeof(sha1), " sha1: %s", digest);
buf_size = sizeof(buf);
gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA256, buf, &buf_size);
_utils_data_to_hex((uint8 *)buf, buf_size, digest, sizeof(digest));
snprintf(sha256, sizeof(sha256), " sha256: %s", digest);
/* render cert info into out */
snprintf(out, size,
"%s\n"
"%s\n"
"%s"
"%s"
"\n"
" Certificate fingerprints:\n\n"
"%s\n"
"%s\n", subject, issuer, valid_from, valid_to, sha1, sha256);
}
static int
_utils_cert_san_to_string(gnutls_x509_crt_t cert, char *out, size_t size)
{
int i, res;
char entries[1024] = {0};
char san[128] = {0};
ssize_t left;
size_t san_size;
unsigned int san_type, critical;
left = sizeof(entries);
for(i = 0; i < 50; i++)
{
san_size = sizeof(san);
res = gnutls_x509_crt_get_subject_alt_name2(cert, i, san, &san_size, &san_type, &critical);
/* break if there are no more SAN entries */
if (res <= 0)
break;
/* log if we cant handle more san entires in buffer */
if (left <= 0)
{
logger(Core, Warning, "%s(), buffer is full, at least one SAN entry is missing from list", __func__);
break;
}
/* add SAN entry to list */
switch(san_type)
{
case GNUTLS_SAN_IPADDRESS:
case GNUTLS_SAN_DNSNAME:
if (left < (ssize_t)sizeof(entries))
{
strncat(entries, ", ", left);
left -= 2;
}
strncat(entries, san, left);
left -= strlen(san);
break;
}
}
if (strlen(entries) == 0)
{
return 1;
}
snprintf(out, size, "%s", entries);
return 0;
}
static void
_utils_cert_get_status_report(gnutls_x509_crt_t cert, unsigned int status,
RD_BOOL hostname_mismatch, const char *hostname,
char *out, size_t size)
{
int i;
char buf[1024];
char str[1024 + 64];
i = 1;
if (hostname_mismatch == True)
{
snprintf(buf, sizeof(buf),
" %d. The hostname used for this connection does not match any of the names\n"
" given in the certificate.\n\n"
" Hostname: %s\n"
, i++, hostname);
strncat(out, buf, size - 1);
size -= strlen(buf);
/* parse subject dn */
gnutls_x509_dn_t dn;
gnutls_x509_crt_get_subject(cert, &dn);
memset(buf, 0, sizeof(buf));
if (_utils_dn_to_string(dn, True, buf, sizeof(buf)) == 0)
{
snprintf(str, sizeof(str), " Common Name: %s\n", buf);
strncat(out, str, size);
size -= strlen(str);
}
/* get SAN entries */
if (_utils_cert_san_to_string(cert, buf, sizeof(buf)) == 0)
{
snprintf(str, sizeof(str), " Alternate names: %s\n", buf);
strncat(out, str, size);
size -= strlen(str);
}
strcat(out, "\n");
size -= 1;
}
if (status & GNUTLS_CERT_REVOKED) {
snprintf(buf, sizeof(buf),
" %d. Certificate is revoked by its authority\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_SIGNER_NOT_FOUND) {
snprintf(buf, sizeof(buf),
" %d. Certificate issuer is not trusted by this system.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
/* parse subject dn */
gnutls_x509_dn_t dn;
gnutls_x509_crt_get_issuer(cert, &dn);
memset(buf, 0, sizeof(buf));
if (_utils_dn_to_string(dn, False, buf, sizeof(buf)) == 0)
{
snprintf(str, sizeof(str), " Issuer: %s\n\n", buf);
strncat(out, str, size);
size -= strlen(str);
}
}
if (status & GNUTLS_CERT_SIGNER_NOT_CA) {
snprintf(buf, sizeof(buf),
" %d. Certificate signer is not a CA.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_INSECURE_ALGORITHM) {
snprintf(buf, sizeof(buf),
" %d. Certificate was signed using an insecure algorithm.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
/* TODO: print algorithm*/
}
if (status & GNUTLS_CERT_NOT_ACTIVATED) {
snprintf(buf, sizeof(buf),
" %d. Certificate is not yet activated.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
time_t ts = gnutls_x509_crt_get_activation_time(cert);
snprintf(buf, sizeof(buf), " Valid From: %s\n\n", ctime(&ts));
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_EXPIRED) {
snprintf(buf, sizeof(buf),
" %d. Certificate has expired.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
time_t ts = gnutls_x509_crt_get_expiration_time(cert);
snprintf(buf, sizeof(buf), " Valid to: %s\n\n", ctime(&ts));
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_SIGNATURE_FAILURE) {
snprintf(buf, sizeof(buf),
" %d. Failed to verify the signature of the certificate.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_REVOCATION_DATA_SUPERSEDED) {
snprintf(buf, sizeof(buf),
" %d. Revocation data are old and have been superseded.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_UNEXPECTED_OWNER) {
snprintf(buf, sizeof(buf),
" %d. The owner is not the expected one.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_REVOCATION_DATA_ISSUED_IN_FUTURE) {
snprintf(buf, sizeof(buf),
" %d. The revocation data have a future issue date.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_SIGNER_CONSTRAINTS_FAILURE) {
snprintf(buf, sizeof(buf),
" %d. The certificate's signer constraints were violated.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_MISMATCH) {
snprintf(buf, sizeof(buf),
" %d. The certificate presented isn't the expected one (TOFU)\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
#if GNUTLS_VERSION_NUMBER >= 0x030400
if (status & GNUTLS_CERT_PURPOSE_MISMATCH) {
snprintf(buf, sizeof(buf),
" %d. The certificate or an intermediate does not match the\n"
" intended purpose (extended key usage).\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
#endif
#if GNUTLS_VERSION_NUMBER >= 0x030501
if (status & GNUTLS_CERT_MISSING_OCSP_STATUS) {
snprintf(buf, sizeof(buf),
" %d. The certificate requires the server to send the certifiate\n"
" status, but no status was received.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
if (status & GNUTLS_CERT_INVALID_OCSP_STATUS) {
snprintf(buf, sizeof(buf),
" %d. The received OCSP status response is invalid.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
#endif
#if GNUTLS_VERSION_NUMBER >= 0x030600
if (status & GNUTLS_CERT_UNKNOWN_CRIT_EXTENSIONS) {
snprintf(buf, sizeof(buf),
" %d. The certificate has extensions marked as critical which are\n"
" not supported.\n\n", i++);
strncat(out, buf, size);
size -= strlen(buf);
}
#endif
}
static int
_utils_cert_store_get_filename(char *out, size_t size)
{
int rv;
char *home;
char dir[PATH_MAX - 12];
struct stat sb;
home = getenv("HOME");
if (home == NULL)
return 1;
if (snprintf(dir, sizeof(dir) - 1, "%s/%s", home, ".local/share/rdesktop/certs/") > (int)sizeof(dir))
{
logger(Core, Error, "%s(), certificate store directory is truncated", __func__);
return 1;
}
if ((rv = stat(dir, &sb)) == -1)
{
if (errno == ENOENT)
{
if (rd_certcache_mkdir() == False) {
logger(Core, Error, "%s(), failed to create directory '%s'", __func__, dir);
return 1;
}
}
}
else
{
if ((sb.st_mode & S_IFMT) != S_IFDIR)
{
logger(Core, Error, "%s(), %s exists but it's not a directory",
__func__, dir);
return 1;
}
}
if (snprintf(out, size, "%s/known_certs", dir) > (int)size)
{
logger(Core, Error, "%s(), certificate store filename is truncated", __func__);
return 1;
}
return 0;
}
#define TRUST_CERT_PROMPT_TEXT "Do you trust this certificate (yes/no)? "
#define REVIEW_CERT_TEXT \
"Review the following certificate info before you trust it to be added as an exception.\n" \
"If you do not trust the certificate the connection atempt will be aborted:"
int
utils_cert_handle_exception(gnutls_session_t session, unsigned int status,
RD_BOOL hostname_mismatch, const char *hostname)
{
int rv;
int type;
time_t exp_time;
gnutls_x509_crt_t cert;
const gnutls_datum_t *cert_list;
unsigned int cert_list_size = 0;
char certcache_fn[PATH_MAX];
char cert_info[2048] = {0};
char cert_invalid_reasons[2048] = {0};
char message[8192] = {0};
const char *response;
/* get filename for certificate exception store */
if (_utils_cert_store_get_filename(certcache_fn, sizeof(certcache_fn)) != 0)
{
logger(Core, Error, "%s(), Failed to get certificate store file, "
"disabling exception handling.", __func__);
return 1;
}
type = gnutls_certificate_type_get(session);
if (type != GNUTLS_CRT_X509)
{
logger(Core, Error, "%s(), Certificate for session is not an x509 certificate, "
"disabling exception handling.", __func__);
return 1;
}
cert_list = gnutls_certificate_get_peers(session, &cert_list_size);
if (cert_list_size == 0)
{
logger(Core, Error, "%s(), Failed to get certificate, "
"disabling exception handling.", __func__);
return 1;
}
rv = gnutls_verify_stored_pubkey(certcache_fn, NULL, hostname, "rdesktop", type, &cert_list[0], 0);
if (rv == GNUTLS_E_SUCCESS)
{
/* Certificate found in store and matches server */
logger(Core, Warning, "Certificate received from server is NOT trusted by this system, "
"an exception has been added by the user to trust this specific certificate.");
return 0;
}
else if (rv != GNUTLS_E_CERTIFICATE_KEY_MISMATCH && rv != GNUTLS_E_NO_CERTIFICATE_FOUND)
{
/* Unhandled errors */
logger(Core, Error, "%s(), verification for host '%s' certificate failed. Error = 0x%x (%s)",
__func__, hostname, rv, gnutls_strerror(rv));
return 1;
}
/*
* Give user possibility to add / update certificate to store