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- Committer: Teddy Hogeborn
- Date: 2018-02-10 21:07:42 UTC
- mfrom: (237.4.94 release)
- Revision ID: teddy@recompile.se-20180210210742-v7hu1g3x5jpix3zx
Merge from release branch
added
removed
plugins.d/mandos-client.c
9
9
* "browse_callback", and parts of "main".
10
10
*
11
11
* Everything else is
12
* Copyright © 2008-2012 Teddy Hogeborn
13
* Copyright © 2008-2012 Björn Påhlsson
14
*
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
19
*
20
* This program is distributed in the hope that it will be useful, but
12
* Copyright © 2008-2018 Teddy Hogeborn
13
* Copyright © 2008-2018 Björn Påhlsson
14
*
15
* This file is part of Mandos.
16
*
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
21
*
22
* Mandos is distributed in the hope that it will be useful, but
21
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
25
* General Public License for more details.
24
26
*
25
27
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
28
29
*
29
30
* Contact the authors at <mandos@recompile.se>.
30
31
*/
32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
33
34
#ifndef _LARGEFILE_SOURCE
34
35
#define _LARGEFILE_SOURCE
35
#endif
36
#endif /* not _LARGEFILE_SOURCE */
36
37
#ifndef _FILE_OFFSET_BITS
37
38
#define _FILE_OFFSET_BITS 64
38
#endif
39
#endif /* not _FILE_OFFSET_BITS */
39
40
40
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
42
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
stdout, ferror() */
44
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
46
#include <stddef.h> /* NULL, size_t, ssize_t */
46
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
48
strtof(), abort() */
48
49
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
52
*/
51
53
#include <sys/ioctl.h> /* ioctl */
52
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
55
sockaddr_in6, PF_INET6,
55
57
opendir(), DIR */
56
58
#include <sys/stat.h> /* open(), S_ISREG */
57
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
61
getnameinfo() */
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
64
*/
62
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
66
strtoimax() */
64
#include <errno.h> /* perror(), errno,
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
68
EAI_SYSTEM, ENETUNREACH,
69
EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
71
ENOTEMPTY,
65
72
program_invocation_short_name */
66
73
#include <time.h> /* nanosleep(), time(), sleep() */
67
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
72
79
*/
73
80
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
81
getuid(), getgid(), seteuid(),
75
setgid(), pause(), _exit() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
82
setgid(), pause(), _exit(),
83
unlinkat() */
84
#include <arpa/inet.h> /* inet_pton(), htons() */
77
85
#include <iso646.h> /* not, or, and */
78
86
#include <argp.h> /* struct argp_option, error_t, struct
79
87
argp_state, struct argp,
91
99
argz_delete(), argz_append(),
92
100
argz_stringify(), argz_add(),
93
101
argz_count() */
102
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
103
EAI_SYSTEM, gai_strerror() */
94
104
95
105
#ifdef __linux__
96
106
#include <sys/klog.h> /* klogctl() */
138
148
static const char sys_class_net[] = "/sys/class/net";
139
149
char *connect_to = NULL;
140
150
const char *hookdir = HOOKDIR;
151
int hookdir_fd = -1;
141
152
uid_t uid = 65534;
142
153
gid_t gid = 65534;
143
154
154
165
155
166
/* Used for passing in values through the Avahi callback functions */
156
167
typedef struct {
157
AvahiSimplePoll *simple_poll;
158
168
AvahiServer *server;
159
169
gnutls_certificate_credentials_t cred;
160
170
unsigned int dh_bits;
162
172
const char *priority;
163
173
gpgme_ctx_t ctx;
164
174
server *current_server;
175
char *interfaces;
176
size_t interfaces_size;
165
177
} mandos_context;
166
178
167
/* global context so signal handler can reach it*/
168
mandos_context mc = { .simple_poll = NULL, .server = NULL,
169
.dh_bits = 1024, .priority = "SECURE256"
170
":!CTYPE-X.509:+CTYPE-OPENPGP",
171
.current_server = NULL };
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
172
181
173
182
sig_atomic_t quit_now = 0;
174
183
int signal_received = 0;
182
191
perror(print_text);
183
192
}
184
193
185
__attribute__((format (gnu_printf, 2, 3)))
194
__attribute__((format (gnu_printf, 2, 3), nonnull))
186
195
int fprintf_plus(FILE *stream, const char *format, ...){
187
196
va_list ap;
188
197
va_start (ap, format);
189
198
190
199
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
191
200
program_invocation_short_name));
192
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
201
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
193
202
}
194
203
195
204
/*
197
206
* bytes. "buffer_capacity" is how much is currently allocated,
198
207
* "buffer_length" is how much is already used.
199
208
*/
209
__attribute__((nonnull, warn_unused_result))
200
210
size_t incbuffer(char **buffer, size_t buffer_length,
201
211
size_t buffer_capacity){
202
212
if(buffer_length + BUFFER_SIZE > buffer_capacity){
203
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
204
if(buffer == NULL){
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
214
if(new_buf == NULL){
215
int old_errno = errno;
216
free(*buffer);
217
errno = old_errno;
218
*buffer = NULL;
205
219
return 0;
206
220
}
221
*buffer = new_buf;
207
222
buffer_capacity += BUFFER_SIZE;
208
223
}
209
224
return buffer_capacity;
210
225
}
211
226
212
227
/* Add server to set of servers to retry periodically */
228
__attribute__((nonnull, warn_unused_result))
213
229
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
214
int af){
230
int af, server **current_server){
215
231
int ret;
216
232
server *new_server = malloc(sizeof(server));
217
233
if(new_server == NULL){
224
240
.af = af };
225
241
if(new_server->ip == NULL){
226
242
perror_plus("strdup");
243
free(new_server);
244
return false;
245
}
246
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
247
if(ret == -1){
248
perror_plus("clock_gettime");
249
#ifdef __GNUC__
250
#pragma GCC diagnostic push
251
#pragma GCC diagnostic ignored "-Wcast-qual"
252
#endif
253
free((char *)(new_server->ip));
254
#ifdef __GNUC__
255
#pragma GCC diagnostic pop
256
#endif
257
free(new_server);
227
258
return false;
228
259
}
229
260
/* Special case of first server */
230
if (mc.current_server == NULL){
261
if(*current_server == NULL){
231
262
new_server->next = new_server;
232
263
new_server->prev = new_server;
233
mc.current_server = new_server;
234
/* Place the new server last in the list */
264
*current_server = new_server;
235
265
} else {
236
new_server->next = mc.current_server;
237
new_server->prev = mc.current_server->prev;
266
/* Place the new server last in the list */
267
new_server->next = *current_server;
268
new_server->prev = (*current_server)->prev;
238
269
new_server->prev->next = new_server;
239
mc.current_server->prev = new_server;
240
}
241
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
242
if(ret == -1){
243
perror_plus("clock_gettime");
244
return false;
270
(*current_server)->prev = new_server;
245
271
}
246
272
return true;
247
273
}
249
275
/*
250
276
* Initialize GPGME.
251
277
*/
252
static bool init_gpgme(const char *seckey, const char *pubkey,
253
const char *tempdir){
278
__attribute__((nonnull, warn_unused_result))
279
static bool init_gpgme(const char * const seckey,
280
const char * const pubkey,
281
const char * const tempdir,
282
mandos_context *mc){
254
283
gpgme_error_t rc;
255
284
gpgme_engine_info_t engine_info;
256
285
257
258
286
/*
259
287
* Helper function to insert pub and seckey to the engine keyring.
260
288
*/
261
bool import_key(const char *filename){
289
bool import_key(const char * const filename){
262
290
int ret;
263
291
int fd;
264
292
gpgme_data_t pgp_data;
276
304
return false;
277
305
}
278
306
279
rc = gpgme_op_import(mc.ctx, pgp_data);
307
rc = gpgme_op_import(mc->ctx, pgp_data);
280
308
if(rc != GPG_ERR_NO_ERROR){
281
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
282
310
gpgme_strsource(rc), gpgme_strerror(rc));
283
311
return false;
284
312
}
285
313
286
ret = (int)TEMP_FAILURE_RETRY(close(fd));
314
ret = close(fd);
287
315
if(ret == -1){
288
316
perror_plus("close");
289
317
}
326
354
}
327
355
328
356
/* Create new GPGME "context" */
329
rc = gpgme_new(&(mc.ctx));
357
rc = gpgme_new(&(mc->ctx));
330
358
if(rc != GPG_ERR_NO_ERROR){
331
359
fprintf_plus(stderr, "Mandos plugin mandos-client: "
332
360
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
345
373
* Decrypt OpenPGP data.
346
374
* Returns -1 on error
347
375
*/
376
__attribute__((nonnull, warn_unused_result))
348
377
static ssize_t pgp_packet_decrypt(const char *cryptotext,
349
378
size_t crypto_size,
350
char **plaintext){
379
char **plaintext,
380
mandos_context *mc){
351
381
gpgme_data_t dh_crypto, dh_plain;
352
382
gpgme_error_t rc;
353
383
ssize_t ret;
379
409
380
410
/* Decrypt data from the cryptotext data buffer to the plaintext
381
411
data buffer */
382
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
412
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
383
413
if(rc != GPG_ERR_NO_ERROR){
384
414
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
385
415
gpgme_strsource(rc), gpgme_strerror(rc));
386
416
plaintext_length = -1;
387
417
if(debug){
388
418
gpgme_decrypt_result_t result;
389
result = gpgme_op_decrypt_result(mc.ctx);
419
result = gpgme_op_decrypt_result(mc->ctx);
390
420
if(result == NULL){
391
421
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
392
422
} else {
469
499
return plaintext_length;
470
500
}
471
501
472
static const char * safer_gnutls_strerror(int value){
502
__attribute__((warn_unused_result, const))
503
static const char *safe_string(const char *str){
504
if(str == NULL)
505
return "(unknown)";
506
return str;
507
}
508
509
__attribute__((warn_unused_result))
510
static const char *safer_gnutls_strerror(int value){
473
511
const char *ret = gnutls_strerror(value);
474
if(ret == NULL)
475
ret = "(unknown)";
476
return ret;
512
return safe_string(ret);
477
513
}
478
514
479
515
/* GnuTLS log function callback */
516
__attribute__((nonnull))
480
517
static void debuggnutls(__attribute__((unused)) int level,
481
518
const char* string){
482
519
fprintf_plus(stderr, "GnuTLS: %s", string);
483
520
}
484
521
522
__attribute__((nonnull(1, 2, 4), warn_unused_result))
485
523
static int init_gnutls_global(const char *pubkeyfilename,
486
const char *seckeyfilename){
524
const char *seckeyfilename,
525
const char *dhparamsfilename,
526
mandos_context *mc){
487
527
int ret;
528
unsigned int uret;
488
529
489
530
if(debug){
490
531
fprintf_plus(stderr, "Initializing GnuTLS\n");
491
532
}
492
533
493
ret = gnutls_global_init();
494
if(ret != GNUTLS_E_SUCCESS){
495
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
496
safer_gnutls_strerror(ret));
497
return -1;
498
}
499
500
534
if(debug){
501
535
/* "Use a log level over 10 to enable all debugging options."
502
536
* - GnuTLS manual
506
540
}
507
541
508
542
/* OpenPGP credentials */
509
ret = gnutls_certificate_allocate_credentials(&mc.cred);
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
510
544
if(ret != GNUTLS_E_SUCCESS){
511
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
512
546
safer_gnutls_strerror(ret));
513
gnutls_global_deinit();
514
547
return -1;
515
548
}
516
549
522
555
}
523
556
524
557
ret = gnutls_certificate_set_openpgp_key_file
525
(mc.cred, pubkeyfilename, seckeyfilename,
558
(mc->cred, pubkeyfilename, seckeyfilename,
526
559
GNUTLS_OPENPGP_FMT_BASE64);
527
560
if(ret != GNUTLS_E_SUCCESS){
528
561
fprintf_plus(stderr,
534
567
}
535
568
536
569
/* GnuTLS server initialization */
537
ret = gnutls_dh_params_init(&mc.dh_params);
570
ret = gnutls_dh_params_init(&mc->dh_params);
538
571
if(ret != GNUTLS_E_SUCCESS){
539
572
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
540
573
" initialization: %s\n",
541
574
safer_gnutls_strerror(ret));
542
575
goto globalfail;
543
576
}
544
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
545
if(ret != GNUTLS_E_SUCCESS){
546
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
547
safer_gnutls_strerror(ret));
548
goto globalfail;
549
}
550
551
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
577
/* If a Diffie-Hellman parameters file was given, try to use it */
578
if(dhparamsfilename != NULL){
579
gnutls_datum_t params = { .data = NULL, .size = 0 };
580
do {
581
int dhpfile = open(dhparamsfilename, O_RDONLY);
582
if(dhpfile == -1){
583
perror_plus("open");
584
dhparamsfilename = NULL;
585
break;
586
}
587
size_t params_capacity = 0;
588
while(true){
589
params_capacity = incbuffer((char **)¶ms.data,
590
(size_t)params.size,
591
(size_t)params_capacity);
592
if(params_capacity == 0){
593
perror_plus("incbuffer");
594
free(params.data);
595
params.data = NULL;
596
dhparamsfilename = NULL;
597
break;
598
}
599
ssize_t bytes_read = read(dhpfile,
600
params.data + params.size,
601
BUFFER_SIZE);
602
/* EOF */
603
if(bytes_read == 0){
604
break;
605
}
606
/* check bytes_read for failure */
607
if(bytes_read < 0){
608
perror_plus("read");
609
free(params.data);
610
params.data = NULL;
611
dhparamsfilename = NULL;
612
break;
613
}
614
params.size += (unsigned int)bytes_read;
615
}
616
if(params.data == NULL){
617
dhparamsfilename = NULL;
618
}
619
if(dhparamsfilename == NULL){
620
break;
621
}
622
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
623
GNUTLS_X509_FMT_PEM);
624
if(ret != GNUTLS_E_SUCCESS){
625
fprintf_plus(stderr, "Failed to parse DH parameters in file"
626
" \"%s\": %s\n", dhparamsfilename,
627
safer_gnutls_strerror(ret));
628
dhparamsfilename = NULL;
629
}
630
free(params.data);
631
} while(false);
632
}
633
if(dhparamsfilename == NULL){
634
if(mc->dh_bits == 0){
635
/* Find out the optimal number of DH bits */
636
/* Try to read the private key file */
637
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
638
do {
639
int secfile = open(seckeyfilename, O_RDONLY);
640
if(secfile == -1){
641
perror_plus("open");
642
break;
643
}
644
size_t buffer_capacity = 0;
645
while(true){
646
buffer_capacity = incbuffer((char **)&buffer.data,
647
(size_t)buffer.size,
648
(size_t)buffer_capacity);
649
if(buffer_capacity == 0){
650
perror_plus("incbuffer");
651
free(buffer.data);
652
buffer.data = NULL;
653
break;
654
}
655
ssize_t bytes_read = read(secfile,
656
buffer.data + buffer.size,
657
BUFFER_SIZE);
658
/* EOF */
659
if(bytes_read == 0){
660
break;
661
}
662
/* check bytes_read for failure */
663
if(bytes_read < 0){
664
perror_plus("read");
665
free(buffer.data);
666
buffer.data = NULL;
667
break;
668
}
669
buffer.size += (unsigned int)bytes_read;
670
}
671
close(secfile);
672
} while(false);
673
/* If successful, use buffer to parse private key */
674
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
675
if(buffer.data != NULL){
676
{
677
gnutls_openpgp_privkey_t privkey = NULL;
678
ret = gnutls_openpgp_privkey_init(&privkey);
679
if(ret != GNUTLS_E_SUCCESS){
680
fprintf_plus(stderr, "Error initializing OpenPGP key"
681
" structure: %s",
682
safer_gnutls_strerror(ret));
683
free(buffer.data);
684
buffer.data = NULL;
685
} else {
686
ret = gnutls_openpgp_privkey_import
687
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
688
if(ret != GNUTLS_E_SUCCESS){
689
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
690
safer_gnutls_strerror(ret));
691
privkey = NULL;
692
}
693
free(buffer.data);
694
buffer.data = NULL;
695
if(privkey != NULL){
696
/* Use private key to suggest an appropriate
697
sec_param */
698
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
699
gnutls_openpgp_privkey_deinit(privkey);
700
if(debug){
701
fprintf_plus(stderr, "This OpenPGP key implies using"
702
" a GnuTLS security parameter \"%s\".\n",
703
safe_string(gnutls_sec_param_get_name
704
(sec_param)));
705
}
706
}
707
}
708
}
709
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
710
/* Err on the side of caution */
711
sec_param = GNUTLS_SEC_PARAM_ULTRA;
712
if(debug){
713
fprintf_plus(stderr, "Falling back to security parameter"
714
" \"%s\"\n",
715
safe_string(gnutls_sec_param_get_name
716
(sec_param)));
717
}
718
}
719
}
720
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
721
if(uret != 0){
722
mc->dh_bits = uret;
723
if(debug){
724
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
725
" implies %u DH bits; using that.\n",
726
safe_string(gnutls_sec_param_get_name
727
(sec_param)),
728
mc->dh_bits);
729
}
730
} else {
731
fprintf_plus(stderr, "Failed to get implied number of DH"
732
" bits for security parameter \"%s\"): %s\n",
733
safe_string(gnutls_sec_param_get_name
734
(sec_param)),
735
safer_gnutls_strerror(ret));
736
goto globalfail;
737
}
738
} else if(debug){
739
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
740
mc->dh_bits);
741
}
742
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
743
if(ret != GNUTLS_E_SUCCESS){
744
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
745
" bits): %s\n", mc->dh_bits,
746
safer_gnutls_strerror(ret));
747
goto globalfail;
748
}
749
}
750
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
552
751
553
752
return 0;
554
753
555
754
globalfail:
556
755
557
gnutls_certificate_free_credentials(mc.cred);
558
gnutls_global_deinit();
559
gnutls_dh_params_deinit(mc.dh_params);
756
gnutls_certificate_free_credentials(mc->cred);
757
gnutls_dh_params_deinit(mc->dh_params);
560
758
return -1;
561
759
}
562
760
563
static int init_gnutls_session(gnutls_session_t *session){
761
__attribute__((nonnull, warn_unused_result))
762
static int init_gnutls_session(gnutls_session_t *session,
763
mandos_context *mc){
564
764
int ret;
565
765
/* GnuTLS session creation */
566
766
do {
578
778
{
579
779
const char *err;
580
780
do {
581
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
781
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
582
782
if(quit_now){
583
783
gnutls_deinit(*session);
584
784
return -1;
595
795
596
796
do {
597
797
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
598
mc.cred);
798
mc->cred);
599
799
if(quit_now){
600
800
gnutls_deinit(*session);
601
801
return -1;
611
811
/* ignore client certificate if any. */
612
812
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
613
813
614
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
615
616
814
return 0;
617
815
}
618
816
620
818
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
621
819
__attribute__((unused)) const char *txt){}
622
820
821
/* Set effective uid to 0, return errno */
822
__attribute__((warn_unused_result))
823
int raise_privileges(void){
824
int old_errno = errno;
825
int ret = 0;
826
if(seteuid(0) == -1){
827
ret = errno;
828
}
829
errno = old_errno;
830
return ret;
831
}
832
833
/* Set effective and real user ID to 0. Return errno. */
834
__attribute__((warn_unused_result))
835
int raise_privileges_permanently(void){
836
int old_errno = errno;
837
int ret = raise_privileges();
838
if(ret != 0){
839
errno = old_errno;
840
return ret;
841
}
842
if(setuid(0) == -1){
843
ret = errno;
844
}
845
errno = old_errno;
846
return ret;
847
}
848
849
/* Set effective user ID to unprivileged saved user ID */
850
__attribute__((warn_unused_result))
851
int lower_privileges(void){
852
int old_errno = errno;
853
int ret = 0;
854
if(seteuid(uid) == -1){
855
ret = errno;
856
}
857
errno = old_errno;
858
return ret;
859
}
860
861
/* Lower privileges permanently */
862
__attribute__((warn_unused_result))
863
int lower_privileges_permanently(void){
864
int old_errno = errno;
865
int ret = 0;
866
if(setuid(uid) == -1){
867
ret = errno;
868
}
869
errno = old_errno;
870
return ret;
871
}
872
873
/* Helper function to add_local_route() and delete_local_route() */
874
__attribute__((nonnull, warn_unused_result))
875
static bool add_delete_local_route(const bool add,
876
const char *address,
877
AvahiIfIndex if_index){
878
int ret;
879
char helper[] = "mandos-client-iprouteadddel";
880
char add_arg[] = "add";
881
char delete_arg[] = "delete";
882
char debug_flag[] = "--debug";
883
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
884
if(pluginhelperdir == NULL){
885
if(debug){
886
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
887
" variable not set; cannot run helper\n");
888
}
889
return false;
890
}
891
892
char interface[IF_NAMESIZE];
893
if(if_indextoname((unsigned int)if_index, interface) == NULL){
894
perror_plus("if_indextoname");
895
return false;
896
}
897
898
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
899
if(devnull == -1){
900
perror_plus("open(\"/dev/null\", O_RDONLY)");
901
return false;
902
}
903
pid_t pid = fork();
904
if(pid == 0){
905
/* Child */
906
/* Raise privileges */
907
errno = raise_privileges_permanently();
908
if(errno != 0){
909
perror_plus("Failed to raise privileges");
910
/* _exit(EX_NOPERM); */
911
} else {
912
/* Set group */
913
errno = 0;
914
ret = setgid(0);
915
if(ret == -1){
916
perror_plus("setgid");
917
_exit(EX_NOPERM);
918
}
919
/* Reset supplementary groups */
920
errno = 0;
921
ret = setgroups(0, NULL);
922
if(ret == -1){
923
perror_plus("setgroups");
924
_exit(EX_NOPERM);
925
}
926
}
927
ret = dup2(devnull, STDIN_FILENO);
928
if(ret == -1){
929
perror_plus("dup2(devnull, STDIN_FILENO)");
930
_exit(EX_OSERR);
931
}
932
ret = close(devnull);
933
if(ret == -1){
934
perror_plus("close");
935
_exit(EX_OSERR);
936
}
937
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
938
if(ret == -1){
939
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
940
_exit(EX_OSERR);
941
}
942
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
943
O_RDONLY
944
| O_DIRECTORY
945
| O_PATH
946
| O_CLOEXEC));
947
if(helperdir_fd == -1){
948
perror_plus("open");
949
_exit(EX_UNAVAILABLE);
950
}
951
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
952
helper, O_RDONLY));
953
if(helper_fd == -1){
954
perror_plus("openat");
955
close(helperdir_fd);
956
_exit(EX_UNAVAILABLE);
957
}
958
close(helperdir_fd);
959
#ifdef __GNUC__
960
#pragma GCC diagnostic push
961
#pragma GCC diagnostic ignored "-Wcast-qual"
962
#endif
963
if(fexecve(helper_fd, (char *const [])
964
{ helper, add ? add_arg : delete_arg, (char *)address,
965
interface, debug ? debug_flag : NULL, NULL },
966
environ) == -1){
967
#ifdef __GNUC__
968
#pragma GCC diagnostic pop
969
#endif
970
perror_plus("fexecve");
971
_exit(EXIT_FAILURE);
972
}
973
}
974
if(pid == -1){
975
perror_plus("fork");
976
return false;
977
}
978
int status;
979
pid_t pret = -1;
980
errno = 0;
981
do {
982
pret = waitpid(pid, &status, 0);
983
if(pret == -1 and errno == EINTR and quit_now){
984
int errno_raising = 0;
985
if((errno = raise_privileges()) != 0){
986
errno_raising = errno;
987
perror_plus("Failed to raise privileges in order to"
988
" kill helper program");
989
}
990
if(kill(pid, SIGTERM) == -1){
991
perror_plus("kill");
992
}
993
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
994
perror_plus("Failed to lower privileges after killing"
995
" helper program");
996
}
997
return false;
998
}
999
} while(pret == -1 and errno == EINTR);
1000
if(pret == -1){
1001
perror_plus("waitpid");
1002
return false;
1003
}
1004
if(WIFEXITED(status)){
1005
if(WEXITSTATUS(status) != 0){
1006
fprintf_plus(stderr, "Error: iprouteadddel exited"
1007
" with status %d\n", WEXITSTATUS(status));
1008
return false;
1009
}
1010
return true;
1011
}
1012
if(WIFSIGNALED(status)){
1013
fprintf_plus(stderr, "Error: iprouteadddel died by"
1014
" signal %d\n", WTERMSIG(status));
1015
return false;
1016
}
1017
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1018
return false;
1019
}
1020
1021
__attribute__((nonnull, warn_unused_result))
1022
static bool add_local_route(const char *address,
1023
AvahiIfIndex if_index){
1024
if(debug){
1025
fprintf_plus(stderr, "Adding route to %s\n", address);
1026
}
1027
return add_delete_local_route(true, address, if_index);
1028
}
1029
1030
__attribute__((nonnull, warn_unused_result))
1031
static bool delete_local_route(const char *address,
1032
AvahiIfIndex if_index){
1033
if(debug){
1034
fprintf_plus(stderr, "Removing route to %s\n", address);
1035
}
1036
return add_delete_local_route(false, address, if_index);
1037
}
1038
623
1039
/* Called when a Mandos server is found */
1040
__attribute__((nonnull, warn_unused_result))
624
1041
static int start_mandos_communication(const char *ip, in_port_t port,
625
1042
AvahiIfIndex if_index,
626
int af){
1043
int af, mandos_context *mc){
627
1044
int ret, tcp_sd = -1;
628
1045
ssize_t sret;
629
union {
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
632
} to;
1046
struct sockaddr_storage to;
633
1047
char *buffer = NULL;
634
1048
char *decrypted_buffer = NULL;
635
1049
size_t buffer_length = 0;
638
1052
int retval = -1;
639
1053
gnutls_session_t session;
640
1054
int pf; /* Protocol family */
1055
bool route_added = false;
641
1056
642
1057
errno = 0;
643
1058
659
1074
return -1;
660
1075
}
661
1076
662
ret = init_gnutls_session(&session);
1077
/* If the interface is specified and we have a list of interfaces */
1078
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1079
/* Check if the interface is one of the interfaces we are using */
1080
bool match = false;
1081
{
1082
char *interface = NULL;
1083
while((interface = argz_next(mc->interfaces,
1084
mc->interfaces_size,
1085
interface))){
1086
if(if_nametoindex(interface) == (unsigned int)if_index){
1087
match = true;
1088
break;
1089
}
1090
}
1091
}
1092
if(not match){
1093
/* This interface does not match any in the list, so we don't
1094
connect to the server */
1095
if(debug){
1096
char interface[IF_NAMESIZE];
1097
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1098
perror_plus("if_indextoname");
1099
} else {
1100
fprintf_plus(stderr, "Skipping server on non-used interface"
1101
" \"%s\"\n",
1102
if_indextoname((unsigned int)if_index,
1103
interface));
1104
}
1105
}
1106
return -1;
1107
}
1108
}
1109
1110
ret = init_gnutls_session(&session, mc);
663
1111
if(ret != 0){
664
1112
return -1;
665
1113
}
669
1117
PRIuMAX "\n", ip, (uintmax_t)port);
670
1118
}
671
1119
672
tcp_sd = socket(pf, SOCK_STREAM, 0);
1120
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
673
1121
if(tcp_sd < 0){
674
1122
int e = errno;
675
1123
perror_plus("socket");
682
1130
goto mandos_end;
683
1131
}
684
1132
685
memset(&to, 0, sizeof(to));
686
1133
if(af == AF_INET6){
687
to.in6.sin6_family = (sa_family_t)af;
688
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1134
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1135
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to6->sin6_addr);
689
1137
} else { /* IPv4 */
690
to.in.sin_family = (sa_family_t)af;
691
ret = inet_pton(af, ip, &to.in.sin_addr);
1138
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1139
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1140
ret = inet_pton(af, ip, &to4->sin_addr);
692
1141
}
693
1142
if(ret < 0 ){
694
1143
int e = errno;
703
1152
goto mandos_end;
704
1153
}
705
1154
if(af == AF_INET6){
706
to.in6.sin6_port = htons(port);
707
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
708
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
709
-Wunreachable-code*/
1155
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1156
if(IN6_IS_ADDR_LINKLOCAL
1157
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
710
1158
if(if_index == AVAHI_IF_UNSPEC){
711
1159
fprintf_plus(stderr, "An IPv6 link-local address is"
712
1160
" incomplete without a network interface\n");
714
1162
goto mandos_end;
715
1163
}
716
1164
/* Set the network interface number as scope */
717
to.in6.sin6_scope_id = (uint32_t)if_index;
1165
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
718
1166
}
719
1167
} else {
720
to.in.sin_port = htons(port); /* Spurious warnings from
721
-Wconversion and
722
-Wunreachable-code */
1168
((struct sockaddr_in *)&to)->sin_port = htons(port);
723
1169
}
724
1170
725
1171
if(quit_now){
742
1188
}
743
1189
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
744
1190
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
745
const char *pcret;
746
if(af == AF_INET6){
747
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
748
sizeof(addrstr));
749
} else {
750
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
751
sizeof(addrstr));
752
}
753
if(pcret == NULL){
754
perror_plus("inet_ntop");
755
} else {
756
if(strcmp(addrstr, ip) != 0){
757
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
758
}
759
}
760
}
761
762
if(quit_now){
763
errno = EINTR;
764
goto mandos_end;
765
}
766
767
if(af == AF_INET6){
768
ret = connect(tcp_sd, &to.in6, sizeof(to));
769
} else {
770
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
771
}
772
if(ret < 0){
773
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
774
int e = errno;
775
perror_plus("connect");
776
errno = e;
777
}
778
goto mandos_end;
779
}
780
781
if(quit_now){
782
errno = EINTR;
783
goto mandos_end;
1191
if(af == AF_INET6){
1192
ret = getnameinfo((struct sockaddr *)&to,
1193
sizeof(struct sockaddr_in6),
1194
addrstr, sizeof(addrstr), NULL, 0,
1195
NI_NUMERICHOST);
1196
} else {
1197
ret = getnameinfo((struct sockaddr *)&to,
1198
sizeof(struct sockaddr_in),
1199
addrstr, sizeof(addrstr), NULL, 0,
1200
NI_NUMERICHOST);
1201
}
1202
if(ret == EAI_SYSTEM){
1203
perror_plus("getnameinfo");
1204
} else if(ret != 0) {
1205
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1206
} else if(strcmp(addrstr, ip) != 0){
1207
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1208
}
1209
}
1210
1211
if(quit_now){
1212
errno = EINTR;
1213
goto mandos_end;
1214
}
1215
1216
while(true){
1217
if(af == AF_INET6){
1218
ret = connect(tcp_sd, (struct sockaddr *)&to,
1219
sizeof(struct sockaddr_in6));
1220
} else {
1221
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1222
sizeof(struct sockaddr_in));
1223
}
1224
if(ret < 0){
1225
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1226
and if_index != AVAHI_IF_UNSPEC
1227
and connect_to == NULL
1228
and not route_added and
1229
((af == AF_INET6 and not
1230
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1231
&to)->sin6_addr)))
1232
or (af == AF_INET and
1233
/* Not a a IPv4LL address */
1234
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1235
& 0xFFFF0000L) != 0xA9FE0000L))){
1236
/* Work around Avahi bug - Avahi does not announce link-local
1237
addresses if it has a global address, so local hosts with
1238
*only* a link-local address (e.g. Mandos clients) cannot
1239
connect to a Mandos server announced by Avahi on a server
1240
host with a global address. Work around this by retrying
1241
with an explicit route added with the server's address.
1242
1243
Avahi bug reference:
1244
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1245
https://bugs.debian.org/587961
1246
*/
1247
if(debug){
1248
fprintf_plus(stderr, "Mandos server unreachable, trying"
1249
" direct route\n");
1250
}
1251
int e = errno;
1252
route_added = add_local_route(ip, if_index);
1253
if(route_added){
1254
continue;
1255
}
1256
errno = e;
1257
}
1258
if(errno != ECONNREFUSED or debug){
1259
int e = errno;
1260
perror_plus("connect");
1261
errno = e;
1262
}
1263
goto mandos_end;
1264
}
1265
1266
if(quit_now){
1267
errno = EINTR;
1268
goto mandos_end;
1269
}
1270
break;
784
1271
}
785
1272
786
1273
const char *out = mandos_protocol_version;
937
1424
if(buffer_length > 0){
938
1425
ssize_t decrypted_buffer_size;
939
1426
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
940
&decrypted_buffer);
1427
&decrypted_buffer, mc);
941
1428
if(decrypted_buffer_size >= 0){
942
1429
1430
clearerr(stdout);
943
1431
written = 0;
944
1432
while(written < (size_t) decrypted_buffer_size){
945
1433
if(quit_now){
961
1449
}
962
1450
written += (size_t)ret;
963
1451
}
1452
ret = fflush(stdout);
1453
if(ret != 0){
1454
int e = errno;
1455
if(debug){
1456
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1457
strerror(errno));
1458
}
1459
errno = e;
1460
goto mandos_end;
1461
}
964
1462
retval = 0;
965
1463
}
966
1464
}
969
1467
970
1468
mandos_end:
971
1469
{
1470
if(route_added){
1471
if(not delete_local_route(ip, if_index)){
1472
fprintf_plus(stderr, "Failed to delete local route to %s on"
1473
" interface %d", ip, if_index);
1474
}
1475
}
972
1476
int e = errno;
973
1477
free(decrypted_buffer);
974
1478
free(buffer);
975
1479
if(tcp_sd >= 0){
976
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1480
ret = close(tcp_sd);
977
1481
}
978
1482
if(ret == -1){
979
1483
if(e == 0){
1004
1508
AVAHI_GCC_UNUSED AvahiStringList *txt,
1005
1509
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1006
1510
flags,
1007
AVAHI_GCC_UNUSED void* userdata){
1511
void *mc){
1008
1512
if(r == NULL){
1009
1513
return;
1010
1514
}
1013
1517
timed out */
1014
1518
1015
1519
if(quit_now){
1520
avahi_s_service_resolver_free(r);
1016
1521
return;
1017
1522
}
1018
1523
1022
1527
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1023
1528
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1024
1529
domain,
1025
avahi_strerror(avahi_server_errno(mc.server)));
1530
avahi_strerror(avahi_server_errno
1531
(((mandos_context*)mc)->server)));
1026
1532
break;
1027
1533
1028
1534
case AVAHI_RESOLVER_FOUND:
1036
1542
}
1037
1543
int ret = start_mandos_communication(ip, (in_port_t)port,
1038
1544
interface,
1039
avahi_proto_to_af(proto));
1545
avahi_proto_to_af(proto),
1546
mc);
1040
1547
if(ret == 0){
1041
avahi_simple_poll_quit(mc.simple_poll);
1548
avahi_simple_poll_quit(simple_poll);
1042
1549
} else {
1043
1550
if(not add_server(ip, (in_port_t)port, interface,
1044
avahi_proto_to_af(proto))){
1551
avahi_proto_to_af(proto),
1552
&((mandos_context*)mc)->current_server)){
1045
1553
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1046
1554
" list\n", name);
1047
1555
}
1060
1568
const char *domain,
1061
1569
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1062
1570
flags,
1063
AVAHI_GCC_UNUSED void* userdata){
1571
void *mc){
1064
1572
if(b == NULL){
1065
1573
return;
1066
1574
}
1077
1585
case AVAHI_BROWSER_FAILURE:
1078
1586
1079
1587
fprintf_plus(stderr, "(Avahi browser) %s\n",
1080
avahi_strerror(avahi_server_errno(mc.server)));
1081
avahi_simple_poll_quit(mc.simple_poll);
1588
avahi_strerror(avahi_server_errno
1589
(((mandos_context*)mc)->server)));
1590
avahi_simple_poll_quit(simple_poll);
1082
1591
return;
1083
1592
1084
1593
case AVAHI_BROWSER_NEW:
1087
1596
the callback function is called the Avahi server will free the
1088
1597
resolver for us. */
1089
1598
1090
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1091
name, type, domain, protocol, 0,
1092
resolve_callback, NULL) == NULL)
1599
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1600
interface, protocol, name, type,
1601
domain, protocol, 0,
1602
resolve_callback, mc) == NULL)
1093
1603
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1094
1604
" %s\n", name,
1095
avahi_strerror(avahi_server_errno(mc.server)));
1605
avahi_strerror(avahi_server_errno
1606
(((mandos_context*)mc)->server)));
1096
1607
break;
1097
1608
1098
1609
case AVAHI_BROWSER_REMOVE:
1117
1628
signal_received = sig;
1118
1629
int old_errno = errno;
1119
1630
/* set main loop to exit */
1120
if(mc.simple_poll != NULL){
1121
avahi_simple_poll_quit(mc.simple_poll);
1631
if(simple_poll != NULL){
1632
avahi_simple_poll_quit(simple_poll);
1122
1633
}
1123
1634
errno = old_errno;
1124
1635
}
1125
1636
1637
__attribute__((nonnull, warn_unused_result))
1126
1638
bool get_flags(const char *ifname, struct ifreq *ifr){
1127
1639
int ret;
1128
error_t ret_errno;
1640
int old_errno;
1129
1641
1130
1642
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1131
1643
if(s < 0){
1132
ret_errno = errno;
1644
old_errno = errno;
1133
1645
perror_plus("socket");
1134
errno = ret_errno;
1646
errno = old_errno;
1135
1647
return false;
1136
1648
}
1137
strcpy(ifr->ifr_name, ifname);
1649
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1650
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1138
1651
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1139
1652
if(ret == -1){
1140
1653
if(debug){
1141
ret_errno = errno;
1654
old_errno = errno;
1142
1655
perror_plus("ioctl SIOCGIFFLAGS");
1143
errno = ret_errno;
1656
errno = old_errno;
1144
1657
}
1145
1658
return false;
1146
1659
}
1147
1660
return true;
1148
1661
}
1149
1662
1663
__attribute__((nonnull, warn_unused_result))
1150
1664
bool good_flags(const char *ifname, const struct ifreq *ifr){
1151
1665
1152
1666
/* Reject the loopback device */
1194
1708
* corresponds to an acceptable network device.
1195
1709
* (This function is passed to scandir(3) as a filter function.)
1196
1710
*/
1711
__attribute__((nonnull, warn_unused_result))
1197
1712
int good_interface(const struct dirent *if_entry){
1198
1713
if(if_entry->d_name[0] == '.'){
1199
1714
return 0;
1217
1732
/*
1218
1733
* This function determines if a network interface is up.
1219
1734
*/
1735
__attribute__((nonnull, warn_unused_result))
1220
1736
bool interface_is_up(const char *interface){
1221
1737
struct ifreq ifr;
1222
1738
if(not get_flags(interface, &ifr)){
1233
1749
/*
1234
1750
* This function determines if a network interface is running
1235
1751
*/
1752
__attribute__((nonnull, warn_unused_result))
1236
1753
bool interface_is_running(const char *interface){
1237
1754
struct ifreq ifr;
1238
1755
if(not get_flags(interface, &ifr)){
1246
1763
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1247
1764
}
1248
1765
1766
__attribute__((nonnull, pure, warn_unused_result))
1249
1767
int notdotentries(const struct dirent *direntry){
1250
1768
/* Skip "." and ".." */
1251
1769
if(direntry->d_name[0] == '.'
1258
1776
}
1259
1777
1260
1778
/* Is this directory entry a runnable program? */
1779
__attribute__((nonnull, warn_unused_result))
1261
1780
int runnable_hook(const struct dirent *direntry){
1262
1781
int ret;
1263
1782
size_t sret;
1271
1790
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1272
1791
"abcdefghijklmnopqrstuvwxyz"
1273
1792
"0123456789"
1274
"_-");
1793
"_.-");
1275
1794
if((direntry->d_name)[sret] != '\0'){
1276
1795
/* Contains non-allowed characters */
1277
1796
if(debug){
1281
1800
return 0;
1282
1801
}
1283
1802
1284
char *fullname = NULL;
1285
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1286
if(ret < 0){
1287
perror_plus("asprintf");
1288
return 0;
1289
}
1290
1291
ret = stat(fullname, &st);
1803
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1292
1804
if(ret == -1){
1293
1805
if(debug){
1294
1806
perror_plus("Could not stat hook");
1318
1830
return 1;
1319
1831
}
1320
1832
1321
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1833
__attribute__((nonnull, warn_unused_result))
1834
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1835
mandos_context *mc){
1322
1836
int ret;
1323
1837
struct timespec now;
1324
1838
struct timespec waited_time;
1325
1839
intmax_t block_time;
1326
1840
1327
1841
while(true){
1328
if(mc.current_server == NULL){
1329
if (debug){
1842
if(mc->current_server == NULL){
1843
if(debug){
1330
1844
fprintf_plus(stderr, "Wait until first server is found."
1331
1845
" No timeout!\n");
1332
1846
}
1333
1847
ret = avahi_simple_poll_iterate(s, -1);
1334
1848
} else {
1335
if (debug){
1849
if(debug){
1336
1850
fprintf_plus(stderr, "Check current_server if we should run"
1337
1851
" it, or wait\n");
1338
1852
}
1345
1859
/* Calculating in ms how long time between now and server
1346
1860
who we visted longest time ago. Now - last seen. */
1347
1861
waited_time.tv_sec = (now.tv_sec
1348
- mc.current_server->last_seen.tv_sec);
1862
- mc->current_server->last_seen.tv_sec);
1349
1863
waited_time.tv_nsec = (now.tv_nsec
1350
- mc.current_server->last_seen.tv_nsec);
1864
- mc->current_server->last_seen.tv_nsec);
1351
1865
/* total time is 10s/10,000ms.
1352
1866
Converting to s from ms by dividing by 1,000,
1353
1867
and ns to ms by dividing by 1,000,000. */
1355
1869
- ((intmax_t)waited_time.tv_sec * 1000))
1356
1870
- ((intmax_t)waited_time.tv_nsec / 1000000));
1357
1871
1358
if (debug){
1872
if(debug){
1359
1873
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1360
1874
block_time);
1361
1875
}
1362
1876
1363
1877
if(block_time <= 0){
1364
ret = start_mandos_communication(mc.current_server->ip,
1365
mc.current_server->port,
1366
mc.current_server->if_index,
1367
mc.current_server->af);
1878
ret = start_mandos_communication(mc->current_server->ip,
1879
mc->current_server->port,
1880
mc->current_server->if_index,
1881
mc->current_server->af, mc);
1368
1882
if(ret == 0){
1369
avahi_simple_poll_quit(mc.simple_poll);
1883
avahi_simple_poll_quit(s);
1370
1884
return 0;
1371
1885
}
1372
1886
ret = clock_gettime(CLOCK_MONOTONIC,
1373
&mc.current_server->last_seen);
1887
&mc->current_server->last_seen);
1374
1888
if(ret == -1){
1375
1889
perror_plus("clock_gettime");
1376
1890
return -1;
1377
1891
}
1378
mc.current_server = mc.current_server->next;
1892
mc->current_server = mc->current_server->next;
1379
1893
block_time = 0; /* Call avahi to find new Mandos
1380
1894
servers, but don't block */
1381
1895
}
1383
1897
ret = avahi_simple_poll_iterate(s, (int)block_time);
1384
1898
}
1385
1899
if(ret != 0){
1386
if (ret > 0 or errno != EINTR){
1900
if(ret > 0 or errno != EINTR){
1387
1901
return (ret != 1) ? ret : 0;
1388
1902
}
1389
1903
}
1390
1904
}
1391
1905
}
1392
1906
1393
/* Set effective uid to 0, return errno */
1394
error_t raise_privileges(void){
1395
error_t old_errno = errno;
1396
error_t ret_errno = 0;
1397
if(seteuid(0) == -1){
1398
ret_errno = errno;
1399
perror_plus("seteuid");
1400
}
1401
errno = old_errno;
1402
return ret_errno;
1403
}
1404
1405
/* Set effective and real user ID to 0. Return errno. */
1406
error_t raise_privileges_permanently(void){
1407
error_t old_errno = errno;
1408
error_t ret_errno = raise_privileges();
1409
if(ret_errno != 0){
1410
errno = old_errno;
1411
return ret_errno;
1412
}
1413
if(setuid(0) == -1){
1414
ret_errno = errno;
1415
perror_plus("seteuid");
1416
}
1417
errno = old_errno;
1418
return ret_errno;
1419
}
1420
1421
/* Set effective user ID to unprivileged saved user ID */
1422
error_t lower_privileges(void){
1423
error_t old_errno = errno;
1424
error_t ret_errno = 0;
1425
if(seteuid(uid) == -1){
1426
ret_errno = errno;
1427
perror_plus("seteuid");
1428
}
1429
errno = old_errno;
1430
return ret_errno;
1431
}
1432
1433
/* Lower privileges permanently */
1434
error_t lower_privileges_permanently(void){
1435
error_t old_errno = errno;
1436
error_t ret_errno = 0;
1437
if(setuid(uid) == -1){
1438
ret_errno = errno;
1439
perror_plus("setuid");
1440
}
1441
errno = old_errno;
1442
return ret_errno;
1443
}
1444
1445
bool run_network_hooks(const char *mode, const char *interface,
1907
__attribute__((nonnull))
1908
void run_network_hooks(const char *mode, const char *interface,
1446
1909
const float delay){
1447
struct dirent **direntries;
1448
struct dirent *direntry;
1449
int ret;
1450
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1451
alphasort);
1910
struct dirent **direntries = NULL;
1911
if(hookdir_fd == -1){
1912
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1913
| O_CLOEXEC);
1914
if(hookdir_fd == -1){
1915
if(errno == ENOENT){
1916
if(debug){
1917
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1918
" found\n", hookdir);
1919
}
1920
} else {
1921
perror_plus("open");
1922
}
1923
return;
1924
}
1925
}
1926
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1927
runnable_hook, alphasort);
1452
1928
if(numhooks == -1){
1453
1929
perror_plus("scandir");
1454
} else {
1455
int devnull = open("/dev/null", O_RDONLY);
1456
for(int i = 0; i < numhooks; i++){
1457
direntry = direntries[i];
1458
char *fullname = NULL;
1459
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1460
if(ret < 0){
1930
return;
1931
}
1932
struct dirent *direntry;
1933
int ret;
1934
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1935
if(devnull == -1){
1936
perror_plus("open(\"/dev/null\", O_RDONLY)");
1937
return;
1938
}
1939
for(int i = 0; i < numhooks; i++){
1940
direntry = direntries[i];
1941
if(debug){
1942
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1943
direntry->d_name);
1944
}
1945
pid_t hook_pid = fork();
1946
if(hook_pid == 0){
1947
/* Child */
1948
/* Raise privileges */
1949
errno = raise_privileges_permanently();
1950
if(errno != 0){
1951
perror_plus("Failed to raise privileges");
1952
_exit(EX_NOPERM);
1953
}
1954
/* Set group */
1955
errno = 0;
1956
ret = setgid(0);
1957
if(ret == -1){
1958
perror_plus("setgid");
1959
_exit(EX_NOPERM);
1960
}
1961
/* Reset supplementary groups */
1962
errno = 0;
1963
ret = setgroups(0, NULL);
1964
if(ret == -1){
1965
perror_plus("setgroups");
1966
_exit(EX_NOPERM);
1967
}
1968
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1969
if(ret == -1){
1970
perror_plus("setenv");
1971
_exit(EX_OSERR);
1972
}
1973
ret = setenv("DEVICE", interface, 1);
1974
if(ret == -1){
1975
perror_plus("setenv");
1976
_exit(EX_OSERR);
1977
}
1978
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1979
if(ret == -1){
1980
perror_plus("setenv");
1981
_exit(EX_OSERR);
1982
}
1983
ret = setenv("MODE", mode, 1);
1984
if(ret == -1){
1985
perror_plus("setenv");
1986
_exit(EX_OSERR);
1987
}
1988
char *delaystring;
1989
ret = asprintf(&delaystring, "%f", (double)delay);
1990
if(ret == -1){
1461
1991
perror_plus("asprintf");
1462
continue;
1463
}
1464
if(debug){
1465
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1466
direntry->d_name);
1467
}
1468
pid_t hook_pid = fork();
1469
if(hook_pid == 0){
1470
/* Child */
1471
/* Raise privileges */
1472
raise_privileges_permanently();
1473
/* Set group */
1474
errno = 0;
1475
ret = setgid(0);
1476
if(ret == -1){
1477
perror_plus("setgid");
1478
}
1479
/* Reset supplementary groups */
1480
errno = 0;
1481
ret = setgroups(0, NULL);
1482
if(ret == -1){
1483
perror_plus("setgroups");
1484
}
1485
dup2(devnull, STDIN_FILENO);
1486
close(devnull);
1487
dup2(STDERR_FILENO, STDOUT_FILENO);
1488
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1489
if(ret == -1){
1490
perror_plus("setenv");
1491
_exit(EX_OSERR);
1492
}
1493
ret = setenv("DEVICE", interface, 1);
1494
if(ret == -1){
1495
perror_plus("setenv");
1496
_exit(EX_OSERR);
1497
}
1498
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1499
if(ret == -1){
1500
perror_plus("setenv");
1501
_exit(EX_OSERR);
1502
}
1503
ret = setenv("MODE", mode, 1);
1504
if(ret == -1){
1505
perror_plus("setenv");
1506
_exit(EX_OSERR);
1507
}
1508
char *delaystring;
1509
ret = asprintf(&delaystring, "%f", delay);
1510
if(ret == -1){
1511
perror_plus("asprintf");
1512
_exit(EX_OSERR);
1513
}
1514
ret = setenv("DELAY", delaystring, 1);
1515
if(ret == -1){
1516
free(delaystring);
1517
perror_plus("setenv");
1518
_exit(EX_OSERR);
1519
}
1992
_exit(EX_OSERR);
1993
}
1994
ret = setenv("DELAY", delaystring, 1);
1995
if(ret == -1){
1520
1996
free(delaystring);
1521
if(connect_to != NULL){
1522
ret = setenv("CONNECT", connect_to, 1);
1523
if(ret == -1){
1524
perror_plus("setenv");
1525
_exit(EX_OSERR);
1526
}
1527
}
1528
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1529
perror_plus("execl");
1530
_exit(EXIT_FAILURE);
1531
}
1997
perror_plus("setenv");
1998
_exit(EX_OSERR);
1999
}
2000
free(delaystring);
2001
if(connect_to != NULL){
2002
ret = setenv("CONNECT", connect_to, 1);
2003
if(ret == -1){
2004
perror_plus("setenv");
2005
_exit(EX_OSERR);
2006
}
2007
}
2008
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2009
direntry->d_name,
2010
O_RDONLY));
2011
if(hook_fd == -1){
2012
perror_plus("openat");
2013
_exit(EXIT_FAILURE);
2014
}
2015
if(close(hookdir_fd) == -1){
2016
perror_plus("close");
2017
_exit(EXIT_FAILURE);
2018
}
2019
ret = dup2(devnull, STDIN_FILENO);
2020
if(ret == -1){
2021
perror_plus("dup2(devnull, STDIN_FILENO)");
2022
_exit(EX_OSERR);
2023
}
2024
ret = close(devnull);
2025
if(ret == -1){
2026
perror_plus("close");
2027
_exit(EX_OSERR);
2028
}
2029
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2030
if(ret == -1){
2031
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2032
_exit(EX_OSERR);
2033
}
2034
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2035
environ) == -1){
2036
perror_plus("fexecve");
2037
_exit(EXIT_FAILURE);
2038
}
2039
} else {
2040
if(hook_pid == -1){
2041
perror_plus("fork");
2042
free(direntry);
2043
continue;
2044
}
2045
int status;
2046
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2047
perror_plus("waitpid");
2048
free(direntry);
2049
continue;
2050
}
2051
if(WIFEXITED(status)){
2052
if(WEXITSTATUS(status) != 0){
2053
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2054
" with status %d\n", direntry->d_name,
2055
WEXITSTATUS(status));
2056
free(direntry);
2057
continue;
2058
}
2059
} else if(WIFSIGNALED(status)){
2060
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2061
" signal %d\n", direntry->d_name,
2062
WTERMSIG(status));
2063
free(direntry);
2064
continue;
1532
2065
} else {
1533
int status;
1534
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1535
perror_plus("waitpid");
1536
free(fullname);
1537
continue;
1538
}
1539
if(WIFEXITED(status)){
1540
if(WEXITSTATUS(status) != 0){
1541
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1542
" with status %d\n", direntry->d_name,
1543
WEXITSTATUS(status));
1544
free(fullname);
1545
continue;
1546
}
1547
} else if(WIFSIGNALED(status)){
1548
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1549
" signal %d\n", direntry->d_name,
1550
WTERMSIG(status));
1551
free(fullname);
1552
continue;
1553
} else {
1554
fprintf_plus(stderr, "Warning: network hook \"%s\""
1555
" crashed\n", direntry->d_name);
1556
free(fullname);
1557
continue;
1558
}
1559
}
1560
free(fullname);
1561
if(debug){
1562
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1563
direntry->d_name);
1564
}
1565
}
1566
close(devnull);
1567
}
1568
return true;
2066
fprintf_plus(stderr, "Warning: network hook \"%s\""
2067
" crashed\n", direntry->d_name);
2068
free(direntry);
2069
continue;
2070
}
2071
}
2072
if(debug){
2073
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2074
direntry->d_name);
2075
}
2076
free(direntry);
2077
}
2078
free(direntries);
2079
if(close(hookdir_fd) == -1){
2080
perror_plus("close");
2081
} else {
2082
hookdir_fd = -1;
2083
}
2084
close(devnull);
1569
2085
}
1570
2086
1571
error_t bring_up_interface(const char *const interface,
1572
const float delay){
1573
int sd = -1;
1574
error_t old_errno = errno;
1575
error_t ret_errno = 0;
1576
int ret, ret_setflags;
2087
__attribute__((nonnull, warn_unused_result))
2088
int bring_up_interface(const char *const interface,
2089
const float delay){
2090
int old_errno = errno;
2091
int ret;
1577
2092
struct ifreq network;
1578
2093
unsigned int if_index = if_nametoindex(interface);
1579
2094
if(if_index == 0){
1588
2103
}
1589
2104
1590
2105
if(not interface_is_up(interface)){
1591
if(not get_flags(interface, &network) and debug){
2106
int ret_errno = 0;
2107
int ioctl_errno = 0;
2108
if(not get_flags(interface, &network)){
1592
2109
ret_errno = errno;
1593
2110
fprintf_plus(stderr, "Failed to get flags for interface "
1594
2111
"\"%s\"\n", interface);
2112
errno = old_errno;
1595
2113
return ret_errno;
1596
2114
}
1597
network.ifr_flags |= IFF_UP;
2115
network.ifr_flags |= IFF_UP; /* set flag */
1598
2116
1599
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1600
if(sd < 0){
2117
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2118
if(sd == -1){
1601
2119
ret_errno = errno;
1602
2120
perror_plus("socket");
1603
2121
errno = old_errno;
1604
2122
return ret_errno;
1605
2123
}
1606
2124
1607
2125
if(quit_now){
1608
close(sd);
2126
ret = close(sd);
2127
if(ret == -1){
2128
perror_plus("close");
2129
}
1609
2130
errno = old_errno;
1610
2131
return EINTR;
1611
2132
}
1615
2136
interface);
1616
2137
}
1617
2138
1618
/* Raise priviliges */
1619
raise_privileges();
2139
/* Raise privileges */
2140
ret_errno = raise_privileges();
2141
if(ret_errno != 0){
2142
errno = ret_errno;
2143
perror_plus("Failed to raise privileges");
2144
}
1620
2145
1621
2146
#ifdef __linux__
1622
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1623
messages about the network interface to mess up the prompt */
1624
int ret_linux = klogctl(8, NULL, 5);
1625
bool restore_loglevel = true;
1626
if(ret_linux == -1){
1627
restore_loglevel = false;
1628
perror_plus("klogctl");
2147
int ret_linux;
2148
bool restore_loglevel = false;
2149
if(ret_errno == 0){
2150
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2151
messages about the network interface to mess up the prompt */
2152
ret_linux = klogctl(8, NULL, 5);
2153
if(ret_linux == -1){
2154
perror_plus("klogctl");
2155
} else {
2156
restore_loglevel = true;
2157
}
1629
2158
}
1630
2159
#endif /* __linux__ */
1631
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1632
ret_errno = errno;
2160
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2161
ioctl_errno = errno;
1633
2162
#ifdef __linux__
1634
2163
if(restore_loglevel){
1635
2164
ret_linux = klogctl(7, NULL, 0);
1639
2168
}
1640
2169
#endif /* __linux__ */
1641
2170
1642
/* Lower privileges */
1643
lower_privileges();
2171
/* If raise_privileges() succeeded above */
2172
if(ret_errno == 0){
2173
/* Lower privileges */
2174
ret_errno = lower_privileges();
2175
if(ret_errno != 0){
2176
errno = ret_errno;
2177
perror_plus("Failed to lower privileges");
2178
}
2179
}
1644
2180
1645
2181
/* Close the socket */
1646
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2182
ret = close(sd);
1647
2183
if(ret == -1){
1648
2184
perror_plus("close");
1649
2185
}
1650
2186
1651
2187
if(ret_setflags == -1){
1652
errno = ret_errno;
2188
errno = ioctl_errno;
1653
2189
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1654
2190
errno = old_errno;
1655
return ret_errno;
2191
return ioctl_errno;
1656
2192
}
1657
2193
} else if(debug){
1658
2194
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1661
2197
1662
2198
/* Sleep checking until interface is running.
1663
2199
Check every 0.25s, up to total time of delay */
1664
for(int i=0; i < delay * 4; i++){
2200
for(int i = 0; i < delay * 4; i++){
1665
2201
if(interface_is_running(interface)){
1666
2202
break;
1667
2203
}
1676
2212
return 0;
1677
2213
}
1678
2214
1679
error_t take_down_interface(const char *const interface){
1680
int sd = -1;
1681
error_t old_errno = errno;
1682
error_t ret_errno = 0;
1683
int ret, ret_setflags;
2215
__attribute__((nonnull, warn_unused_result))
2216
int take_down_interface(const char *const interface){
2217
int old_errno = errno;
1684
2218
struct ifreq network;
1685
2219
unsigned int if_index = if_nametoindex(interface);
1686
2220
if(if_index == 0){
1689
2223
return ENXIO;
1690
2224
}
1691
2225
if(interface_is_up(interface)){
2226
int ret_errno = 0;
2227
int ioctl_errno = 0;
1692
2228
if(not get_flags(interface, &network) and debug){
1693
2229
ret_errno = errno;
1694
2230
fprintf_plus(stderr, "Failed to get flags for interface "
1695
2231
"\"%s\"\n", interface);
2232
errno = old_errno;
1696
2233
return ret_errno;
1697
2234
}
1698
2235
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1699
2236
1700
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1701
if(sd < 0){
2237
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2238
if(sd == -1){
1702
2239
ret_errno = errno;
1703
2240
perror_plus("socket");
1704
2241
errno = old_errno;
1710
2247
interface);
1711
2248
}
1712
2249
1713
/* Raise priviliges */
1714
raise_privileges();
1715
1716
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1717
ret_errno = errno;
1718
1719
/* Lower privileges */
1720
lower_privileges();
2250
/* Raise privileges */
2251
ret_errno = raise_privileges();
2252
if(ret_errno != 0){
2253
errno = ret_errno;
2254
perror_plus("Failed to raise privileges");
2255
}
2256
2257
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2258
ioctl_errno = errno;
2259
2260
/* If raise_privileges() succeeded above */
2261
if(ret_errno == 0){
2262
/* Lower privileges */
2263
ret_errno = lower_privileges();
2264
if(ret_errno != 0){
2265
errno = ret_errno;
2266
perror_plus("Failed to lower privileges");
2267
}
2268
}
1721
2269
1722
2270
/* Close the socket */
1723
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2271
int ret = close(sd);
1724
2272
if(ret == -1){
1725
2273
perror_plus("close");
1726
2274
}
1727
2275
1728
2276
if(ret_setflags == -1){
1729
errno = ret_errno;
2277
errno = ioctl_errno;
1730
2278
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1731
2279
errno = old_errno;
1732
return ret_errno;
2280
return ioctl_errno;
1733
2281
}
1734
2282
} else if(debug){
1735
2283
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1741
2289
}
1742
2290
1743
2291
int main(int argc, char *argv[]){
2292
mandos_context mc = { .server = NULL, .dh_bits = 0,
2293
.priority = "SECURE256:!CTYPE-X.509"
2294
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2295
.current_server = NULL, .interfaces = NULL,
2296
.interfaces_size = 0 };
1744
2297
AvahiSServiceBrowser *sb = NULL;
1745
2298
error_t ret_errno;
1746
2299
int ret;
1747
2300
intmax_t tmpmax;
1748
2301
char *tmp;
1749
2302
int exitcode = EXIT_SUCCESS;
1750
char *interfaces = NULL;
1751
size_t interfaces_size = 0;
1752
2303
char *interfaces_to_take_down = NULL;
1753
2304
size_t interfaces_to_take_down_size = 0;
1754
char tempdir[] = "/tmp/mandosXXXXXX";
1755
bool tempdir_created = false;
2305
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2306
char old_tempdir[] = "/tmp/mandosXXXXXX";
2307
char *tempdir = NULL;
1756
2308
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1757
2309
const char *seckey = PATHDIR "/" SECKEY;
1758
2310
const char *pubkey = PATHDIR "/" PUBKEY;
2311
const char *dh_params_file = NULL;
1759
2312
char *interfaces_hooks = NULL;
1760
size_t interfaces_hooks_size = 0;
1761
2313
1762
2314
bool gnutls_initialized = false;
1763
2315
bool gpgme_initialized = false;
1815
2367
.doc = "Bit length of the prime number used in the"
1816
2368
" Diffie-Hellman key exchange",
1817
2369
.group = 2 },
2370
{ .name = "dh-params", .key = 134,
2371
.arg = "FILE",
2372
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2373
" for the Diffie-Hellman key exchange",
2374
.group = 2 },
1818
2375
{ .name = "priority", .key = 130,
1819
2376
.arg = "STRING",
1820
2377
.doc = "GnuTLS priority string for the TLS handshake",
1854
2411
connect_to = arg;
1855
2412
break;
1856
2413
case 'i': /* --interface */
1857
ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,
1858
(int)',');
2414
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2415
arg, (int)',');
1859
2416
if(ret_errno != 0){
1860
2417
argp_error(state, "%s", strerror(ret_errno));
1861
2418
}
1875
2432
}
1876
2433
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1877
2434
break;
2435
case 134: /* --dh-params */
2436
dh_params_file = arg;
2437
break;
1878
2438
case 130: /* --priority */
1879
2439
mc.priority = arg;
1880
2440
break;
1920
2480
.args_doc = "",
1921
2481
.doc = "Mandos client -- Get and decrypt"
1922
2482
" passwords from a Mandos server" };
1923
ret = argp_parse(&argp, argc, argv,
1924
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1925
switch(ret){
2483
ret_errno = argp_parse(&argp, argc, argv,
2484
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2485
switch(ret_errno){
1926
2486
case 0:
1927
2487
break;
1928
2488
case ENOMEM:
1929
2489
default:
1930
errno = ret;
2490
errno = ret_errno;
1931
2491
perror_plus("argp_parse");
1932
2492
exitcode = EX_OSERR;
1933
2493
goto end;
1936
2496
goto end;
1937
2497
}
1938
2498
}
1939
2499
1940
2500
{
1941
2501
/* Work around Debian bug #633582:
1942
<http://bugs.debian.org/633582> */
2502
<https://bugs.debian.org/633582> */
1943
2503
1944
/* Re-raise priviliges */
1945
if(raise_privileges() == 0){
2504
/* Re-raise privileges */
2505
ret = raise_privileges();
2506
if(ret != 0){
2507
errno = ret;
2508
perror_plus("Failed to raise privileges");
2509
} else {
1946
2510
struct stat st;
1947
2511
1948
2512
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1962
2526
}
1963
2527
}
1964
2528
}
1965
TEMP_FAILURE_RETRY(close(seckey_fd));
2529
close(seckey_fd);
1966
2530
}
1967
2531
}
1968
2532
1969
2533
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1970
2534
int pubkey_fd = open(pubkey, O_RDONLY);
1971
2535
if(pubkey_fd == -1){
1983
2547
}
1984
2548
}
1985
2549
}
1986
TEMP_FAILURE_RETRY(close(pubkey_fd));
1987
}
1988
}
1989
2550
close(pubkey_fd);
2551
}
2552
}
2553
2554
if(dh_params_file != NULL
2555
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2556
int dhparams_fd = open(dh_params_file, O_RDONLY);
2557
if(dhparams_fd == -1){
2558
perror_plus("open");
2559
} else {
2560
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2561
if(ret == -1){
2562
perror_plus("fstat");
2563
} else {
2564
if(S_ISREG(st.st_mode)
2565
and st.st_uid == 0 and st.st_gid == 0){
2566
ret = fchown(dhparams_fd, uid, gid);
2567
if(ret == -1){
2568
perror_plus("fchown");
2569
}
2570
}
2571
}
2572
close(dhparams_fd);
2573
}
2574
}
2575
1990
2576
/* Lower privileges */
1991
errno = 0;
1992
ret = seteuid(uid);
1993
if(ret == -1){
1994
perror_plus("seteuid");
2577
ret = lower_privileges();
2578
if(ret != 0){
2579
errno = ret;
2580
perror_plus("Failed to lower privileges");
1995
2581
}
1996
2582
}
1997
2583
}
1998
2584
1999
/* Remove empty interface names */
2585
/* Remove invalid interface names (except "none") */
2000
2586
{
2001
2587
char *interface = NULL;
2002
while((interface = argz_next(interfaces, interfaces_size,
2588
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2003
2589
interface))){
2004
if(if_nametoindex(interface) == 0){
2005
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2590
if(strcmp(interface, "none") != 0
2591
and if_nametoindex(interface) == 0){
2592
if(interface[0] != '\0'){
2006
2593
fprintf_plus(stderr, "Not using nonexisting interface"
2007
2594
" \"%s\"\n", interface);
2008
2595
}
2009
argz_delete(&interfaces, &interfaces_size, interface);
2596
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2010
2597
interface = NULL;
2011
2598
}
2012
2599
}
2014
2601
2015
2602
/* Run network hooks */
2016
2603
{
2017
ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,
2018
interfaces, interfaces_size);
2019
if(ret_errno != 0){
2020
errno = ret_errno;
2021
perror_plus("argz_append");
2022
goto end;
2023
}
2024
argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');
2025
if(not run_network_hooks("start", interfaces_hooks, delay)){
2026
goto end;
2027
}
2604
if(mc.interfaces != NULL){
2605
interfaces_hooks = malloc(mc.interfaces_size);
2606
if(interfaces_hooks == NULL){
2607
perror_plus("malloc");
2608
goto end;
2609
}
2610
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2611
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2612
}
2613
run_network_hooks("start", interfaces_hooks != NULL ?
2614
interfaces_hooks : "", delay);
2028
2615
}
2029
2616
2030
2617
if(not debug){
2035
2622
from the signal handler */
2036
2623
/* Initialize the pseudo-RNG for Avahi */
2037
2624
srand((unsigned int) time(NULL));
2038
mc.simple_poll = avahi_simple_poll_new();
2039
if(mc.simple_poll == NULL){
2625
simple_poll = avahi_simple_poll_new();
2626
if(simple_poll == NULL){
2040
2627
fprintf_plus(stderr,
2041
2628
"Avahi: Failed to create simple poll object.\n");
2042
2629
exitcode = EX_UNAVAILABLE;
2107
2694
}
2108
2695
2109
2696
/* If no interfaces were specified, make a list */
2110
if(interfaces == NULL){
2111
struct dirent **direntries;
2697
if(mc.interfaces == NULL){
2698
struct dirent **direntries = NULL;
2112
2699
/* Look for any good interfaces */
2113
2700
ret = scandir(sys_class_net, &direntries, good_interface,
2114
2701
alphasort);
2115
2702
if(ret >= 1){
2116
2703
/* Add all found interfaces to interfaces list */
2117
2704
for(int i = 0; i < ret; ++i){
2118
ret_errno = argz_add(&interfaces, &interfaces_size,
2705
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2119
2706
direntries[i]->d_name);
2120
2707
if(ret_errno != 0){
2708
errno = ret_errno;
2121
2709
perror_plus("argz_add");
2710
free(direntries[i]);
2122
2711
continue;
2123
2712
}
2124
2713
if(debug){
2125
2714
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2126
2715
direntries[i]->d_name);
2127
2716
}
2717
free(direntries[i]);
2128
2718
}
2129
2719
free(direntries);
2130
2720
} else {
2131
free(direntries);
2721
if(ret == 0){
2722
free(direntries);
2723
}
2132
2724
fprintf_plus(stderr, "Could not find a network interface\n");
2133
2725
exitcode = EXIT_FAILURE;
2134
2726
goto end;
2135
2727
}
2136
2728
}
2137
2729
2138
/* If we only got one interface, explicitly use only that one */
2139
if(argz_count(interfaces, interfaces_size) == 1){
2140
if(debug){
2141
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2142
interfaces);
2143
}
2144
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2145
}
2146
2147
/* Bring up interfaces which are down */
2148
if(not (argz_count(interfaces, interfaces_size) == 1
2149
and strcmp(interfaces, "none") == 0)){
2730
/* Bring up interfaces which are down, and remove any "none"s */
2731
{
2150
2732
char *interface = NULL;
2151
while((interface = argz_next(interfaces, interfaces_size,
2733
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2152
2734
interface))){
2735
/* If interface name is "none", stop bringing up interfaces.
2736
Also remove all instances of "none" from the list */
2737
if(strcmp(interface, "none") == 0){
2738
argz_delete(&mc.interfaces, &mc.interfaces_size,
2739
interface);
2740
interface = NULL;
2741
while((interface = argz_next(mc.interfaces,
2742
mc.interfaces_size, interface))){
2743
if(strcmp(interface, "none") == 0){
2744
argz_delete(&mc.interfaces, &mc.interfaces_size,
2745
interface);
2746
interface = NULL;
2747
}
2748
}
2749
break;
2750
}
2153
2751
bool interface_was_up = interface_is_up(interface);
2154
ret = bring_up_interface(interface, delay);
2752
errno = bring_up_interface(interface, delay);
2155
2753
if(not interface_was_up){
2156
if(ret != 0){
2157
errno = ret;
2158
perror_plus("Failed to bring up interface");
2754
if(errno != 0){
2755
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2756
" %s\n", interface, strerror(errno));
2159
2757
} else {
2160
ret_errno = argz_add(&interfaces_to_take_down,
2161
&interfaces_to_take_down_size,
2162
interface);
2758
errno = argz_add(&interfaces_to_take_down,
2759
&interfaces_to_take_down_size,
2760
interface);
2761
if(errno != 0){
2762
perror_plus("argz_add");
2763
}
2163
2764
}
2164
2765
}
2165
2766
}
2166
free(interfaces);
2167
interfaces = NULL;
2168
interfaces_size = 0;
2169
2767
if(debug and (interfaces_to_take_down == NULL)){
2170
2768
fprintf_plus(stderr, "No interfaces were brought up\n");
2171
2769
}
2172
2770
}
2173
2771
2772
/* If we only got one interface, explicitly use only that one */
2773
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2774
if(debug){
2775
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2776
mc.interfaces);
2777
}
2778
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2779
}
2780
2174
2781
if(quit_now){
2175
2782
goto end;
2176
2783
}
2177
2784
2178
ret = init_gnutls_global(pubkey, seckey);
2785
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2179
2786
if(ret == -1){
2180
2787
fprintf_plus(stderr, "init_gnutls_global failed\n");
2181
2788
exitcode = EX_UNAVAILABLE;
2188
2795
goto end;
2189
2796
}
2190
2797
2191
if(mkdtemp(tempdir) == NULL){
2798
/* Try /run/tmp before /tmp */
2799
tempdir = mkdtemp(run_tempdir);
2800
if(tempdir == NULL and errno == ENOENT){
2801
if(debug){
2802
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2803
run_tempdir, old_tempdir);
2804
}
2805
tempdir = mkdtemp(old_tempdir);
2806
}
2807
if(tempdir == NULL){
2192
2808
perror_plus("mkdtemp");
2193
2809
goto end;
2194
2810
}
2195
tempdir_created = true;
2196
2811
2197
2812
if(quit_now){
2198
2813
goto end;
2199
2814
}
2200
2815
2201
if(not init_gpgme(pubkey, seckey, tempdir)){
2816
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2202
2817
fprintf_plus(stderr, "init_gpgme failed\n");
2203
2818
exitcode = EX_UNAVAILABLE;
2204
2819
goto end;
2234
2849
exitcode = EX_USAGE;
2235
2850
goto end;
2236
2851
}
2237
2852
2238
2853
if(quit_now){
2239
2854
goto end;
2240
2855
}
2261
2876
}
2262
2877
2263
2878
while(not quit_now){
2264
ret = start_mandos_communication(address, port, if_index, af);
2879
ret = start_mandos_communication(address, port, if_index, af,
2880
&mc);
2265
2881
if(quit_now or ret == 0){
2266
2882
break;
2267
2883
}
2269
2885
fprintf_plus(stderr, "Retrying in %d seconds\n",
2270
2886
(int)retry_interval);
2271
2887
}
2272
sleep((int)retry_interval);
2888
sleep((unsigned int)retry_interval);
2273
2889
}
2274
2890
2275
if (not quit_now){
2891
if(not quit_now){
2276
2892
exitcode = EXIT_SUCCESS;
2277
2893
}
2278
2894
2293
2909
config.publish_domain = 0;
2294
2910
2295
2911
/* Allocate a new server */
2296
mc.server = avahi_server_new(avahi_simple_poll_get
2297
(mc.simple_poll), &config, NULL,
2298
NULL, &ret_errno);
2912
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2913
&config, NULL, NULL, &ret);
2299
2914
2300
2915
/* Free the Avahi configuration data */
2301
2916
avahi_server_config_free(&config);
2304
2919
/* Check if creating the Avahi server object succeeded */
2305
2920
if(mc.server == NULL){
2306
2921
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2307
avahi_strerror(ret_errno));
2922
avahi_strerror(ret));
2308
2923
exitcode = EX_UNAVAILABLE;
2309
2924
goto end;
2310
2925
}
2316
2931
/* Create the Avahi service browser */
2317
2932
sb = avahi_s_service_browser_new(mc.server, if_index,
2318
2933
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2319
NULL, 0, browse_callback, NULL);
2934
NULL, 0, browse_callback,
2935
(void *)&mc);
2320
2936
if(sb == NULL){
2321
2937
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2322
2938
avahi_strerror(avahi_server_errno(mc.server)));
2333
2949
if(debug){
2334
2950
fprintf_plus(stderr, "Starting Avahi loop search\n");
2335
2951
}
2336
2337
ret = avahi_loop_with_timeout(mc.simple_poll,
2338
(int)(retry_interval * 1000));
2952
2953
ret = avahi_loop_with_timeout(simple_poll,
2954
(int)(retry_interval * 1000), &mc);
2339
2955
if(debug){
2340
2956
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2341
2957
(ret == 0) ? "successfully" : "with error");
2344
2960
end:
2345
2961
2346
2962
if(debug){
2347
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2963
if(signal_received){
2964
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
2965
argv[0], signal_received,
2966
strsignal(signal_received));
2967
} else {
2968
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2969
}
2348
2970
}
2349
2971
2350
2972
/* Cleanup things */
2973
free(mc.interfaces);
2974
2351
2975
if(sb != NULL)
2352
2976
avahi_s_service_browser_free(sb);
2353
2977
2354
2978
if(mc.server != NULL)
2355
2979
avahi_server_free(mc.server);
2356
2980
2357
if(mc.simple_poll != NULL)
2358
avahi_simple_poll_free(mc.simple_poll);
2981
if(simple_poll != NULL)
2982
avahi_simple_poll_free(simple_poll);
2359
2983
2360
2984
if(gnutls_initialized){
2361
2985
gnutls_certificate_free_credentials(mc.cred);
2362
gnutls_global_deinit();
2363
2986
gnutls_dh_params_deinit(mc.dh_params);
2364
2987
}
2365
2988
2373
2996
mc.current_server->prev->next = NULL;
2374
2997
while(mc.current_server != NULL){
2375
2998
server *next = mc.current_server->next;
2999
#ifdef __GNUC__
3000
#pragma GCC diagnostic push
3001
#pragma GCC diagnostic ignored "-Wcast-qual"
3002
#endif
3003
free((char *)(mc.current_server->ip));
3004
#ifdef __GNUC__
3005
#pragma GCC diagnostic pop
3006
#endif
2376
3007
free(mc.current_server);
2377
3008
mc.current_server = next;
2378
3009
}
2379
3010
}
2380
3011
2381
/* Re-raise priviliges */
3012
/* Re-raise privileges */
2382
3013
{
2383
raise_privileges();
2384
2385
/* Run network hooks */
2386
run_network_hooks("stop", interfaces_hooks, delay);
2387
2388
/* Take down the network interfaces which were brought up */
2389
{
2390
char *interface = NULL;
2391
while((interface=argz_next(interfaces_to_take_down,
2392
interfaces_to_take_down_size,
2393
interface))){
2394
ret_errno = take_down_interface(interface);
2395
if(ret_errno != 0){
2396
errno = ret_errno;
2397
perror_plus("Failed to take down interface");
2398
}
2399
}
2400
if(debug and (interfaces_to_take_down == NULL)){
2401
fprintf_plus(stderr, "No interfaces needed to be taken"
2402
" down\n");
2403
}
2404
}
2405
2406
lower_privileges_permanently();
3014
ret = raise_privileges();
3015
if(ret != 0){
3016
errno = ret;
3017
perror_plus("Failed to raise privileges");
3018
} else {
3019
3020
/* Run network hooks */
3021
run_network_hooks("stop", interfaces_hooks != NULL ?
3022
interfaces_hooks : "", delay);
3023
3024
/* Take down the network interfaces which were brought up */
3025
{
3026
char *interface = NULL;
3027
while((interface = argz_next(interfaces_to_take_down,
3028
interfaces_to_take_down_size,
3029
interface))){
3030
ret = take_down_interface(interface);
3031
if(ret != 0){
3032
errno = ret;
3033
perror_plus("Failed to take down interface");
3034
}
3035
}
3036
if(debug and (interfaces_to_take_down == NULL)){
3037
fprintf_plus(stderr, "No interfaces needed to be taken"
3038
" down\n");
3039
}
3040
}
3041
}
3042
3043
ret = lower_privileges_permanently();
3044
if(ret != 0){
3045
errno = ret;
3046
perror_plus("Failed to lower privileges permanently");
3047
}
2407
3048
}
2408
3049
2409
3050
free(interfaces_to_take_down);
2410
3051
free(interfaces_hooks);
2411
3052
3053
void clean_dir_at(int base, const char * const dirname,
3054
uintmax_t level){
3055
struct dirent **direntries = NULL;
3056
int dret;
3057
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3058
O_RDONLY
3059
| O_NOFOLLOW
3060
| O_DIRECTORY
3061
| O_PATH));
3062
if(dir_fd == -1){
3063
perror_plus("open");
3064
}
3065
int numentries = scandirat(dir_fd, ".", &direntries,
3066
notdotentries, alphasort);
3067
if(numentries >= 0){
3068
for(int i = 0; i < numentries; i++){
3069
if(debug){
3070
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3071
dirname, direntries[i]->d_name);
3072
}
3073
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3074
if(dret == -1){
3075
if(errno == EISDIR){
3076
dret = unlinkat(dir_fd, direntries[i]->d_name,
3077
AT_REMOVEDIR);
3078
}
3079
if((dret == -1) and (errno == ENOTEMPTY)
3080
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3081
== 0) and (level == 0)){
3082
/* Recurse only in this special case */
3083
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3084
dret = 0;
3085
}
3086
if(dret == -1){
3087
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3088
direntries[i]->d_name, strerror(errno));
3089
}
3090
}
3091
free(direntries[i]);
3092
}
3093
3094
/* need to clean even if 0 because man page doesn't specify */
3095
free(direntries);
3096
if(numentries == -1){
3097
perror_plus("scandirat");
3098
}
3099
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3100
if(dret == -1 and errno != ENOENT){
3101
perror_plus("rmdir");
3102
}
3103
} else {
3104
perror_plus("scandirat");
3105
}
3106
close(dir_fd);
3107
}
3108
2412
3109
/* Removes the GPGME temp directory and all files inside */
2413
if(tempdir_created){
2414
struct dirent **direntries = NULL;
2415
struct dirent *direntry = NULL;
2416
int numentries = scandir(tempdir, &direntries, notdotentries,
2417
alphasort);
2418
if (numentries > 0){
2419
for(int i = 0; i < numentries; i++){
2420
direntry = direntries[i];
2421
char *fullname = NULL;
2422
ret = asprintf(&fullname, "%s/%s", tempdir,
2423
direntry->d_name);
2424
if(ret < 0){
2425
perror_plus("asprintf");
2426
continue;
2427
}
2428
ret = remove(fullname);
2429
if(ret == -1){
2430
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2431
strerror(errno));
2432
}
2433
free(fullname);
2434
}
2435
}
2436
2437
/* need to clean even if 0 because man page doesn't specify */
2438
free(direntries);
2439
if (numentries == -1){
2440
perror_plus("scandir");
2441
}
2442
ret = rmdir(tempdir);
2443
if(ret == -1 and errno != ENOENT){
2444
perror_plus("rmdir");
2445
}
3110
if(tempdir != NULL){
3111
clean_dir_at(-1, tempdir, 0);
2446
3112
}
2447
3113
2448
3114
if(quit_now){
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0