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237.7.432
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: plugins.d/mandos-client.c
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- Committer: Teddy Hogeborn
- Date: 2016-10-29 13:44:49 UTC
- mto: (237.7.594 trunk)
- mto: This revision was merged to the branch mainline in revision 356.
- Revision ID: teddy@recompile.se-20161029134449-imf8eidhzwfnax9w
mandos: Use "self" instead of class name "GnuTLS" in __init__.
* mandos (GnuTLS.__init__): Use "self" instead of class name "GnuTLS".
* mandos (GnuTLS.__init__): Use "self" instead of class name "GnuTLS".
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
12
* Copyright © 2008-2016 Teddy Hogeborn
13
* Copyright © 2008-2016 Björn Påhlsson
14
14
*
15
15
* This program is free software: you can redistribute it and/or
16
16
* modify it under the terms of the GNU General Public License as
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
33
#ifndef _LARGEFILE_SOURCE
34
34
#define _LARGEFILE_SOURCE
35
#endif
35
#endif /* not _LARGEFILE_SOURCE */
36
36
#ifndef _FILE_OFFSET_BITS
37
37
#define _FILE_OFFSET_BITS 64
38
#endif
38
#endif /* not _FILE_OFFSET_BITS */
39
39
40
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
41
42
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
43
stdout, ferror() */
44
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
47
strtof(), abort() */
48
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
49
#include <string.h> /* strcmp(), strlen(), strerror(),
50
asprintf(), strncpy(), strsignal()
51
*/
51
52
#include <sys/ioctl.h> /* ioctl */
52
53
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
54
sockaddr_in6, PF_INET6,
55
56
opendir(), DIR */
56
57
#include <sys/stat.h> /* open(), S_ISREG */
57
58
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
59
inet_pton(), connect(),
60
getnameinfo() */
61
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
62
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
63
*/
62
64
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
65
strtoimax() */
64
#include <errno.h> /* perror(), errno,
66
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
67
EAI_SYSTEM, ENETUNREACH,
68
EHOSTUNREACH, ECONNREFUSED, EPROTO,
69
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
70
ENOTEMPTY,
65
71
program_invocation_short_name */
66
72
#include <time.h> /* nanosleep(), time(), sleep() */
67
73
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
72
78
*/
73
79
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
80
getuid(), getgid(), seteuid(),
75
setgid(), pause(), _exit() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
81
setgid(), pause(), _exit(),
82
unlinkat() */
83
#include <arpa/inet.h> /* inet_pton(), htons() */
77
84
#include <iso646.h> /* not, or, and */
78
85
#include <argp.h> /* struct argp_option, error_t, struct
79
86
argp_state, struct argp,
91
98
argz_delete(), argz_append(),
92
99
argz_stringify(), argz_add(),
93
100
argz_count() */
101
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
102
EAI_SYSTEM, gai_strerror() */
94
103
95
104
#ifdef __linux__
96
105
#include <sys/klog.h> /* klogctl() */
138
147
static const char sys_class_net[] = "/sys/class/net";
139
148
char *connect_to = NULL;
140
149
const char *hookdir = HOOKDIR;
150
int hookdir_fd = -1;
141
151
uid_t uid = 65534;
142
152
gid_t gid = 65534;
143
153
154
164
155
165
/* Used for passing in values through the Avahi callback functions */
156
166
typedef struct {
157
AvahiSimplePoll *simple_poll;
158
167
AvahiServer *server;
159
168
gnutls_certificate_credentials_t cred;
160
169
unsigned int dh_bits;
162
171
const char *priority;
163
172
gpgme_ctx_t ctx;
164
173
server *current_server;
174
char *interfaces;
175
size_t interfaces_size;
165
176
} mandos_context;
166
177
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 };
178
/* global so signal handler can reach it*/
179
AvahiSimplePoll *simple_poll;
172
180
173
181
sig_atomic_t quit_now = 0;
174
182
int signal_received = 0;
182
190
perror(print_text);
183
191
}
184
192
185
__attribute__((format (gnu_printf, 2, 3)))
193
__attribute__((format (gnu_printf, 2, 3), nonnull))
186
194
int fprintf_plus(FILE *stream, const char *format, ...){
187
195
va_list ap;
188
196
va_start (ap, format);
189
197
190
198
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
191
199
program_invocation_short_name));
192
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
200
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
193
201
}
194
202
195
203
/*
197
205
* bytes. "buffer_capacity" is how much is currently allocated,
198
206
* "buffer_length" is how much is already used.
199
207
*/
208
__attribute__((nonnull, warn_unused_result))
200
209
size_t incbuffer(char **buffer, size_t buffer_length,
201
210
size_t buffer_capacity){
202
211
if(buffer_length + BUFFER_SIZE > buffer_capacity){
203
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
204
if(buffer == NULL){
212
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
if(new_buf == NULL){
214
int old_errno = errno;
215
free(*buffer);
216
errno = old_errno;
217
*buffer = NULL;
205
218
return 0;
206
219
}
220
*buffer = new_buf;
207
221
buffer_capacity += BUFFER_SIZE;
208
222
}
209
223
return buffer_capacity;
210
224
}
211
225
212
226
/* Add server to set of servers to retry periodically */
227
__attribute__((nonnull, warn_unused_result))
213
228
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
214
int af){
229
int af, server **current_server){
215
230
int ret;
216
231
server *new_server = malloc(sizeof(server));
217
232
if(new_server == NULL){
224
239
.af = af };
225
240
if(new_server->ip == NULL){
226
241
perror_plus("strdup");
242
free(new_server);
243
return false;
244
}
245
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
246
if(ret == -1){
247
perror_plus("clock_gettime");
248
#ifdef __GNUC__
249
#pragma GCC diagnostic push
250
#pragma GCC diagnostic ignored "-Wcast-qual"
251
#endif
252
free((char *)(new_server->ip));
253
#ifdef __GNUC__
254
#pragma GCC diagnostic pop
255
#endif
256
free(new_server);
227
257
return false;
228
258
}
229
259
/* Special case of first server */
230
if (mc.current_server == NULL){
260
if(*current_server == NULL){
231
261
new_server->next = new_server;
232
262
new_server->prev = new_server;
233
mc.current_server = new_server;
234
/* Place the new server last in the list */
263
*current_server = new_server;
235
264
} else {
236
new_server->next = mc.current_server;
237
new_server->prev = mc.current_server->prev;
265
/* Place the new server last in the list */
266
new_server->next = *current_server;
267
new_server->prev = (*current_server)->prev;
238
268
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;
269
(*current_server)->prev = new_server;
245
270
}
246
271
return true;
247
272
}
249
274
/*
250
275
* Initialize GPGME.
251
276
*/
252
static bool init_gpgme(const char *seckey, const char *pubkey,
253
const char *tempdir){
277
__attribute__((nonnull, warn_unused_result))
278
static bool init_gpgme(const char * const seckey,
279
const char * const pubkey,
280
const char * const tempdir,
281
mandos_context *mc){
254
282
gpgme_error_t rc;
255
283
gpgme_engine_info_t engine_info;
256
284
257
258
285
/*
259
286
* Helper function to insert pub and seckey to the engine keyring.
260
287
*/
261
bool import_key(const char *filename){
288
bool import_key(const char * const filename){
262
289
int ret;
263
290
int fd;
264
291
gpgme_data_t pgp_data;
276
303
return false;
277
304
}
278
305
279
rc = gpgme_op_import(mc.ctx, pgp_data);
306
rc = gpgme_op_import(mc->ctx, pgp_data);
280
307
if(rc != GPG_ERR_NO_ERROR){
281
308
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
282
309
gpgme_strsource(rc), gpgme_strerror(rc));
283
310
return false;
284
311
}
285
312
286
ret = (int)TEMP_FAILURE_RETRY(close(fd));
313
ret = close(fd);
287
314
if(ret == -1){
288
315
perror_plus("close");
289
316
}
326
353
}
327
354
328
355
/* Create new GPGME "context" */
329
rc = gpgme_new(&(mc.ctx));
356
rc = gpgme_new(&(mc->ctx));
330
357
if(rc != GPG_ERR_NO_ERROR){
331
358
fprintf_plus(stderr, "Mandos plugin mandos-client: "
332
359
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
345
372
* Decrypt OpenPGP data.
346
373
* Returns -1 on error
347
374
*/
375
__attribute__((nonnull, warn_unused_result))
348
376
static ssize_t pgp_packet_decrypt(const char *cryptotext,
349
377
size_t crypto_size,
350
char **plaintext){
378
char **plaintext,
379
mandos_context *mc){
351
380
gpgme_data_t dh_crypto, dh_plain;
352
381
gpgme_error_t rc;
353
382
ssize_t ret;
379
408
380
409
/* Decrypt data from the cryptotext data buffer to the plaintext
381
410
data buffer */
382
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
411
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
383
412
if(rc != GPG_ERR_NO_ERROR){
384
413
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
385
414
gpgme_strsource(rc), gpgme_strerror(rc));
386
415
plaintext_length = -1;
387
416
if(debug){
388
417
gpgme_decrypt_result_t result;
389
result = gpgme_op_decrypt_result(mc.ctx);
418
result = gpgme_op_decrypt_result(mc->ctx);
390
419
if(result == NULL){
391
420
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
392
421
} else {
469
498
return plaintext_length;
470
499
}
471
500
472
static const char * safer_gnutls_strerror(int value){
501
__attribute__((warn_unused_result, const))
502
static const char *safe_string(const char *str){
503
if(str == NULL)
504
return "(unknown)";
505
return str;
506
}
507
508
__attribute__((warn_unused_result))
509
static const char *safer_gnutls_strerror(int value){
473
510
const char *ret = gnutls_strerror(value);
474
if(ret == NULL)
475
ret = "(unknown)";
476
return ret;
511
return safe_string(ret);
477
512
}
478
513
479
514
/* GnuTLS log function callback */
515
__attribute__((nonnull))
480
516
static void debuggnutls(__attribute__((unused)) int level,
481
517
const char* string){
482
518
fprintf_plus(stderr, "GnuTLS: %s", string);
483
519
}
484
520
521
__attribute__((nonnull(1, 2, 4), warn_unused_result))
485
522
static int init_gnutls_global(const char *pubkeyfilename,
486
const char *seckeyfilename){
523
const char *seckeyfilename,
524
const char *dhparamsfilename,
525
mandos_context *mc){
487
526
int ret;
527
unsigned int uret;
488
528
489
529
if(debug){
490
530
fprintf_plus(stderr, "Initializing GnuTLS\n");
491
531
}
492
532
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
533
if(debug){
501
534
/* "Use a log level over 10 to enable all debugging options."
502
535
* - GnuTLS manual
506
539
}
507
540
508
541
/* OpenPGP credentials */
509
ret = gnutls_certificate_allocate_credentials(&mc.cred);
542
ret = gnutls_certificate_allocate_credentials(&mc->cred);
510
543
if(ret != GNUTLS_E_SUCCESS){
511
544
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
512
545
safer_gnutls_strerror(ret));
513
gnutls_global_deinit();
514
546
return -1;
515
547
}
516
548
522
554
}
523
555
524
556
ret = gnutls_certificate_set_openpgp_key_file
525
(mc.cred, pubkeyfilename, seckeyfilename,
557
(mc->cred, pubkeyfilename, seckeyfilename,
526
558
GNUTLS_OPENPGP_FMT_BASE64);
527
559
if(ret != GNUTLS_E_SUCCESS){
528
560
fprintf_plus(stderr,
534
566
}
535
567
536
568
/* GnuTLS server initialization */
537
ret = gnutls_dh_params_init(&mc.dh_params);
569
ret = gnutls_dh_params_init(&mc->dh_params);
538
570
if(ret != GNUTLS_E_SUCCESS){
539
571
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
540
572
" initialization: %s\n",
541
573
safer_gnutls_strerror(ret));
542
574
goto globalfail;
543
575
}
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);
576
/* If a Diffie-Hellman parameters file was given, try to use it */
577
if(dhparamsfilename != NULL){
578
gnutls_datum_t params = { .data = NULL, .size = 0 };
579
do {
580
int dhpfile = open(dhparamsfilename, O_RDONLY);
581
if(dhpfile == -1){
582
perror_plus("open");
583
dhparamsfilename = NULL;
584
break;
585
}
586
size_t params_capacity = 0;
587
while(true){
588
params_capacity = incbuffer((char **)¶ms.data,
589
(size_t)params.size,
590
(size_t)params_capacity);
591
if(params_capacity == 0){
592
perror_plus("incbuffer");
593
free(params.data);
594
params.data = NULL;
595
dhparamsfilename = NULL;
596
break;
597
}
598
ssize_t bytes_read = read(dhpfile,
599
params.data + params.size,
600
BUFFER_SIZE);
601
/* EOF */
602
if(bytes_read == 0){
603
break;
604
}
605
/* check bytes_read for failure */
606
if(bytes_read < 0){
607
perror_plus("read");
608
free(params.data);
609
params.data = NULL;
610
dhparamsfilename = NULL;
611
break;
612
}
613
params.size += (unsigned int)bytes_read;
614
}
615
if(params.data == NULL){
616
dhparamsfilename = NULL;
617
}
618
if(dhparamsfilename == NULL){
619
break;
620
}
621
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
622
GNUTLS_X509_FMT_PEM);
623
if(ret != GNUTLS_E_SUCCESS){
624
fprintf_plus(stderr, "Failed to parse DH parameters in file"
625
" \"%s\": %s\n", dhparamsfilename,
626
safer_gnutls_strerror(ret));
627
dhparamsfilename = NULL;
628
}
629
free(params.data);
630
} while(false);
631
}
632
if(dhparamsfilename == NULL){
633
if(mc->dh_bits == 0){
634
/* Find out the optimal number of DH bits */
635
/* Try to read the private key file */
636
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
637
do {
638
int secfile = open(seckeyfilename, O_RDONLY);
639
if(secfile == -1){
640
perror_plus("open");
641
break;
642
}
643
size_t buffer_capacity = 0;
644
while(true){
645
buffer_capacity = incbuffer((char **)&buffer.data,
646
(size_t)buffer.size,
647
(size_t)buffer_capacity);
648
if(buffer_capacity == 0){
649
perror_plus("incbuffer");
650
free(buffer.data);
651
buffer.data = NULL;
652
break;
653
}
654
ssize_t bytes_read = read(secfile,
655
buffer.data + buffer.size,
656
BUFFER_SIZE);
657
/* EOF */
658
if(bytes_read == 0){
659
break;
660
}
661
/* check bytes_read for failure */
662
if(bytes_read < 0){
663
perror_plus("read");
664
free(buffer.data);
665
buffer.data = NULL;
666
break;
667
}
668
buffer.size += (unsigned int)bytes_read;
669
}
670
close(secfile);
671
} while(false);
672
/* If successful, use buffer to parse private key */
673
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
674
if(buffer.data != NULL){
675
{
676
gnutls_openpgp_privkey_t privkey = NULL;
677
ret = gnutls_openpgp_privkey_init(&privkey);
678
if(ret != GNUTLS_E_SUCCESS){
679
fprintf_plus(stderr, "Error initializing OpenPGP key"
680
" structure: %s",
681
safer_gnutls_strerror(ret));
682
free(buffer.data);
683
buffer.data = NULL;
684
} else {
685
ret = gnutls_openpgp_privkey_import
686
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
687
if(ret != GNUTLS_E_SUCCESS){
688
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
689
safer_gnutls_strerror(ret));
690
privkey = NULL;
691
}
692
free(buffer.data);
693
buffer.data = NULL;
694
if(privkey != NULL){
695
/* Use private key to suggest an appropriate
696
sec_param */
697
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
698
gnutls_openpgp_privkey_deinit(privkey);
699
if(debug){
700
fprintf_plus(stderr, "This OpenPGP key implies using"
701
" a GnuTLS security parameter \"%s\".\n",
702
safe_string(gnutls_sec_param_get_name
703
(sec_param)));
704
}
705
}
706
}
707
}
708
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
709
/* Err on the side of caution */
710
sec_param = GNUTLS_SEC_PARAM_ULTRA;
711
if(debug){
712
fprintf_plus(stderr, "Falling back to security parameter"
713
" \"%s\"\n",
714
safe_string(gnutls_sec_param_get_name
715
(sec_param)));
716
}
717
}
718
}
719
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
720
if(uret != 0){
721
mc->dh_bits = uret;
722
if(debug){
723
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
724
" implies %u DH bits; using that.\n",
725
safe_string(gnutls_sec_param_get_name
726
(sec_param)),
727
mc->dh_bits);
728
}
729
} else {
730
fprintf_plus(stderr, "Failed to get implied number of DH"
731
" bits for security parameter \"%s\"): %s\n",
732
safe_string(gnutls_sec_param_get_name
733
(sec_param)),
734
safer_gnutls_strerror(ret));
735
goto globalfail;
736
}
737
} else if(debug){
738
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
739
mc->dh_bits);
740
}
741
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
742
if(ret != GNUTLS_E_SUCCESS){
743
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
744
" bits): %s\n", mc->dh_bits,
745
safer_gnutls_strerror(ret));
746
goto globalfail;
747
}
748
}
749
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
552
750
553
751
return 0;
554
752
555
753
globalfail:
556
754
557
gnutls_certificate_free_credentials(mc.cred);
558
gnutls_global_deinit();
559
gnutls_dh_params_deinit(mc.dh_params);
755
gnutls_certificate_free_credentials(mc->cred);
756
gnutls_dh_params_deinit(mc->dh_params);
560
757
return -1;
561
758
}
562
759
563
static int init_gnutls_session(gnutls_session_t *session){
760
__attribute__((nonnull, warn_unused_result))
761
static int init_gnutls_session(gnutls_session_t *session,
762
mandos_context *mc){
564
763
int ret;
565
764
/* GnuTLS session creation */
566
765
do {
578
777
{
579
778
const char *err;
580
779
do {
581
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
780
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
582
781
if(quit_now){
583
782
gnutls_deinit(*session);
584
783
return -1;
595
794
596
795
do {
597
796
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
598
mc.cred);
797
mc->cred);
599
798
if(quit_now){
600
799
gnutls_deinit(*session);
601
800
return -1;
611
810
/* ignore client certificate if any. */
612
811
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
613
812
614
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
615
616
813
return 0;
617
814
}
618
815
620
817
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
621
818
__attribute__((unused)) const char *txt){}
622
819
820
/* Set effective uid to 0, return errno */
821
__attribute__((warn_unused_result))
822
int raise_privileges(void){
823
int old_errno = errno;
824
int ret = 0;
825
if(seteuid(0) == -1){
826
ret = errno;
827
}
828
errno = old_errno;
829
return ret;
830
}
831
832
/* Set effective and real user ID to 0. Return errno. */
833
__attribute__((warn_unused_result))
834
int raise_privileges_permanently(void){
835
int old_errno = errno;
836
int ret = raise_privileges();
837
if(ret != 0){
838
errno = old_errno;
839
return ret;
840
}
841
if(setuid(0) == -1){
842
ret = errno;
843
}
844
errno = old_errno;
845
return ret;
846
}
847
848
/* Set effective user ID to unprivileged saved user ID */
849
__attribute__((warn_unused_result))
850
int lower_privileges(void){
851
int old_errno = errno;
852
int ret = 0;
853
if(seteuid(uid) == -1){
854
ret = errno;
855
}
856
errno = old_errno;
857
return ret;
858
}
859
860
/* Lower privileges permanently */
861
__attribute__((warn_unused_result))
862
int lower_privileges_permanently(void){
863
int old_errno = errno;
864
int ret = 0;
865
if(setuid(uid) == -1){
866
ret = errno;
867
}
868
errno = old_errno;
869
return ret;
870
}
871
872
/* Helper function to add_local_route() and delete_local_route() */
873
__attribute__((nonnull, warn_unused_result))
874
static bool add_delete_local_route(const bool add,
875
const char *address,
876
AvahiIfIndex if_index){
877
int ret;
878
char helper[] = "mandos-client-iprouteadddel";
879
char add_arg[] = "add";
880
char delete_arg[] = "delete";
881
char debug_flag[] = "--debug";
882
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
883
if(pluginhelperdir == NULL){
884
if(debug){
885
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
886
" variable not set; cannot run helper\n");
887
}
888
return false;
889
}
890
891
char interface[IF_NAMESIZE];
892
if(if_indextoname((unsigned int)if_index, interface) == NULL){
893
perror_plus("if_indextoname");
894
return false;
895
}
896
897
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
898
if(devnull == -1){
899
perror_plus("open(\"/dev/null\", O_RDONLY)");
900
return false;
901
}
902
pid_t pid = fork();
903
if(pid == 0){
904
/* Child */
905
/* Raise privileges */
906
errno = raise_privileges_permanently();
907
if(errno != 0){
908
perror_plus("Failed to raise privileges");
909
/* _exit(EX_NOPERM); */
910
} else {
911
/* Set group */
912
errno = 0;
913
ret = setgid(0);
914
if(ret == -1){
915
perror_plus("setgid");
916
_exit(EX_NOPERM);
917
}
918
/* Reset supplementary groups */
919
errno = 0;
920
ret = setgroups(0, NULL);
921
if(ret == -1){
922
perror_plus("setgroups");
923
_exit(EX_NOPERM);
924
}
925
}
926
ret = dup2(devnull, STDIN_FILENO);
927
if(ret == -1){
928
perror_plus("dup2(devnull, STDIN_FILENO)");
929
_exit(EX_OSERR);
930
}
931
ret = close(devnull);
932
if(ret == -1){
933
perror_plus("close");
934
_exit(EX_OSERR);
935
}
936
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
937
if(ret == -1){
938
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
939
_exit(EX_OSERR);
940
}
941
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
942
O_RDONLY
943
| O_DIRECTORY
944
| O_PATH
945
| O_CLOEXEC));
946
if(helperdir_fd == -1){
947
perror_plus("open");
948
_exit(EX_UNAVAILABLE);
949
}
950
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
951
helper, O_RDONLY));
952
if(helper_fd == -1){
953
perror_plus("openat");
954
close(helperdir_fd);
955
_exit(EX_UNAVAILABLE);
956
}
957
close(helperdir_fd);
958
#ifdef __GNUC__
959
#pragma GCC diagnostic push
960
#pragma GCC diagnostic ignored "-Wcast-qual"
961
#endif
962
if(fexecve(helper_fd, (char *const [])
963
{ helper, add ? add_arg : delete_arg, (char *)address,
964
interface, debug ? debug_flag : NULL, NULL },
965
environ) == -1){
966
#ifdef __GNUC__
967
#pragma GCC diagnostic pop
968
#endif
969
perror_plus("fexecve");
970
_exit(EXIT_FAILURE);
971
}
972
}
973
if(pid == -1){
974
perror_plus("fork");
975
return false;
976
}
977
int status;
978
pid_t pret = -1;
979
errno = 0;
980
do {
981
pret = waitpid(pid, &status, 0);
982
if(pret == -1 and errno == EINTR and quit_now){
983
int errno_raising = 0;
984
if((errno = raise_privileges()) != 0){
985
errno_raising = errno;
986
perror_plus("Failed to raise privileges in order to"
987
" kill helper program");
988
}
989
if(kill(pid, SIGTERM) == -1){
990
perror_plus("kill");
991
}
992
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
993
perror_plus("Failed to lower privileges after killing"
994
" helper program");
995
}
996
return false;
997
}
998
} while(pret == -1 and errno == EINTR);
999
if(pret == -1){
1000
perror_plus("waitpid");
1001
return false;
1002
}
1003
if(WIFEXITED(status)){
1004
if(WEXITSTATUS(status) != 0){
1005
fprintf_plus(stderr, "Error: iprouteadddel exited"
1006
" with status %d\n", WEXITSTATUS(status));
1007
return false;
1008
}
1009
return true;
1010
}
1011
if(WIFSIGNALED(status)){
1012
fprintf_plus(stderr, "Error: iprouteadddel died by"
1013
" signal %d\n", WTERMSIG(status));
1014
return false;
1015
}
1016
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1017
return false;
1018
}
1019
1020
__attribute__((nonnull, warn_unused_result))
1021
static bool add_local_route(const char *address,
1022
AvahiIfIndex if_index){
1023
if(debug){
1024
fprintf_plus(stderr, "Adding route to %s\n", address);
1025
}
1026
return add_delete_local_route(true, address, if_index);
1027
}
1028
1029
__attribute__((nonnull, warn_unused_result))
1030
static bool delete_local_route(const char *address,
1031
AvahiIfIndex if_index){
1032
if(debug){
1033
fprintf_plus(stderr, "Removing route to %s\n", address);
1034
}
1035
return add_delete_local_route(false, address, if_index);
1036
}
1037
623
1038
/* Called when a Mandos server is found */
1039
__attribute__((nonnull, warn_unused_result))
624
1040
static int start_mandos_communication(const char *ip, in_port_t port,
625
1041
AvahiIfIndex if_index,
626
int af){
1042
int af, mandos_context *mc){
627
1043
int ret, tcp_sd = -1;
628
1044
ssize_t sret;
629
union {
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
632
} to;
1045
struct sockaddr_storage to;
633
1046
char *buffer = NULL;
634
1047
char *decrypted_buffer = NULL;
635
1048
size_t buffer_length = 0;
638
1051
int retval = -1;
639
1052
gnutls_session_t session;
640
1053
int pf; /* Protocol family */
1054
bool route_added = false;
641
1055
642
1056
errno = 0;
643
1057
659
1073
return -1;
660
1074
}
661
1075
662
ret = init_gnutls_session(&session);
1076
/* If the interface is specified and we have a list of interfaces */
1077
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1078
/* Check if the interface is one of the interfaces we are using */
1079
bool match = false;
1080
{
1081
char *interface = NULL;
1082
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1083
interface))){
1084
if(if_nametoindex(interface) == (unsigned int)if_index){
1085
match = true;
1086
break;
1087
}
1088
}
1089
}
1090
if(not match){
1091
/* This interface does not match any in the list, so we don't
1092
connect to the server */
1093
if(debug){
1094
char interface[IF_NAMESIZE];
1095
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1096
perror_plus("if_indextoname");
1097
} else {
1098
fprintf_plus(stderr, "Skipping server on non-used interface"
1099
" \"%s\"\n",
1100
if_indextoname((unsigned int)if_index,
1101
interface));
1102
}
1103
}
1104
return -1;
1105
}
1106
}
1107
1108
ret = init_gnutls_session(&session, mc);
663
1109
if(ret != 0){
664
1110
return -1;
665
1111
}
669
1115
PRIuMAX "\n", ip, (uintmax_t)port);
670
1116
}
671
1117
672
tcp_sd = socket(pf, SOCK_STREAM, 0);
1118
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
673
1119
if(tcp_sd < 0){
674
1120
int e = errno;
675
1121
perror_plus("socket");
682
1128
goto mandos_end;
683
1129
}
684
1130
685
memset(&to, 0, sizeof(to));
686
1131
if(af == AF_INET6){
687
to.in6.sin6_family = (sa_family_t)af;
688
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1132
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1133
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1134
ret = inet_pton(af, ip, &to6->sin6_addr);
689
1135
} else { /* IPv4 */
690
to.in.sin_family = (sa_family_t)af;
691
ret = inet_pton(af, ip, &to.in.sin_addr);
1136
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1137
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1138
ret = inet_pton(af, ip, &to4->sin_addr);
692
1139
}
693
1140
if(ret < 0 ){
694
1141
int e = errno;
703
1150
goto mandos_end;
704
1151
}
705
1152
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*/
1153
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1154
if(IN6_IS_ADDR_LINKLOCAL
1155
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
710
1156
if(if_index == AVAHI_IF_UNSPEC){
711
1157
fprintf_plus(stderr, "An IPv6 link-local address is"
712
1158
" incomplete without a network interface\n");
714
1160
goto mandos_end;
715
1161
}
716
1162
/* Set the network interface number as scope */
717
to.in6.sin6_scope_id = (uint32_t)if_index;
1163
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
718
1164
}
719
1165
} else {
720
to.in.sin_port = htons(port); /* Spurious warnings from
721
-Wconversion and
722
-Wunreachable-code */
1166
((struct sockaddr_in *)&to)->sin_port = htons(port);
723
1167
}
724
1168
725
1169
if(quit_now){
742
1186
}
743
1187
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
744
1188
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;
1189
if(af == AF_INET6){
1190
ret = getnameinfo((struct sockaddr *)&to,
1191
sizeof(struct sockaddr_in6),
1192
addrstr, sizeof(addrstr), NULL, 0,
1193
NI_NUMERICHOST);
1194
} else {
1195
ret = getnameinfo((struct sockaddr *)&to,
1196
sizeof(struct sockaddr_in),
1197
addrstr, sizeof(addrstr), NULL, 0,
1198
NI_NUMERICHOST);
1199
}
1200
if(ret == EAI_SYSTEM){
1201
perror_plus("getnameinfo");
1202
} else if(ret != 0) {
1203
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1204
} else if(strcmp(addrstr, ip) != 0){
1205
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1206
}
1207
}
1208
1209
if(quit_now){
1210
errno = EINTR;
1211
goto mandos_end;
1212
}
1213
1214
while(true){
1215
if(af == AF_INET6){
1216
ret = connect(tcp_sd, (struct sockaddr *)&to,
1217
sizeof(struct sockaddr_in6));
1218
} else {
1219
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1220
sizeof(struct sockaddr_in));
1221
}
1222
if(ret < 0){
1223
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1224
and if_index != AVAHI_IF_UNSPEC
1225
and connect_to == NULL
1226
and not route_added and
1227
((af == AF_INET6 and not
1228
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1229
&to)->sin6_addr)))
1230
or (af == AF_INET and
1231
/* Not a a IPv4LL address */
1232
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1233
& 0xFFFF0000L) != 0xA9FE0000L))){
1234
/* Work around Avahi bug - Avahi does not announce link-local
1235
addresses if it has a global address, so local hosts with
1236
*only* a link-local address (e.g. Mandos clients) cannot
1237
connect to a Mandos server announced by Avahi on a server
1238
host with a global address. Work around this by retrying
1239
with an explicit route added with the server's address.
1240
1241
Avahi bug reference:
1242
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1243
https://bugs.debian.org/587961
1244
*/
1245
if(debug){
1246
fprintf_plus(stderr, "Mandos server unreachable, trying"
1247
" direct route\n");
1248
}
1249
int e = errno;
1250
route_added = add_local_route(ip, if_index);
1251
if(route_added){
1252
continue;
1253
}
1254
errno = e;
1255
}
1256
if(errno != ECONNREFUSED or debug){
1257
int e = errno;
1258
perror_plus("connect");
1259
errno = e;
1260
}
1261
goto mandos_end;
1262
}
1263
1264
if(quit_now){
1265
errno = EINTR;
1266
goto mandos_end;
1267
}
1268
break;
784
1269
}
785
1270
786
1271
const char *out = mandos_protocol_version;
937
1422
if(buffer_length > 0){
938
1423
ssize_t decrypted_buffer_size;
939
1424
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
940
&decrypted_buffer);
1425
&decrypted_buffer, mc);
941
1426
if(decrypted_buffer_size >= 0){
942
1427
1428
clearerr(stdout);
943
1429
written = 0;
944
1430
while(written < (size_t) decrypted_buffer_size){
945
1431
if(quit_now){
961
1447
}
962
1448
written += (size_t)ret;
963
1449
}
1450
ret = fflush(stdout);
1451
if(ret != 0){
1452
int e = errno;
1453
if(debug){
1454
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1455
strerror(errno));
1456
}
1457
errno = e;
1458
goto mandos_end;
1459
}
964
1460
retval = 0;
965
1461
}
966
1462
}
969
1465
970
1466
mandos_end:
971
1467
{
1468
if(route_added){
1469
if(not delete_local_route(ip, if_index)){
1470
fprintf_plus(stderr, "Failed to delete local route to %s on"
1471
" interface %d", ip, if_index);
1472
}
1473
}
972
1474
int e = errno;
973
1475
free(decrypted_buffer);
974
1476
free(buffer);
975
1477
if(tcp_sd >= 0){
976
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1478
ret = close(tcp_sd);
977
1479
}
978
1480
if(ret == -1){
979
1481
if(e == 0){
991
1493
return retval;
992
1494
}
993
1495
1496
__attribute__((nonnull))
994
1497
static void resolve_callback(AvahiSServiceResolver *r,
995
1498
AvahiIfIndex interface,
996
1499
AvahiProtocol proto,
1004
1507
AVAHI_GCC_UNUSED AvahiStringList *txt,
1005
1508
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1006
1509
flags,
1007
AVAHI_GCC_UNUSED void* userdata){
1510
void *mc){
1008
1511
if(r == NULL){
1009
1512
return;
1010
1513
}
1013
1516
timed out */
1014
1517
1015
1518
if(quit_now){
1519
avahi_s_service_resolver_free(r);
1016
1520
return;
1017
1521
}
1018
1522
1022
1526
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1023
1527
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1024
1528
domain,
1025
avahi_strerror(avahi_server_errno(mc.server)));
1529
avahi_strerror(avahi_server_errno
1530
(((mandos_context*)mc)->server)));
1026
1531
break;
1027
1532
1028
1533
case AVAHI_RESOLVER_FOUND:
1036
1541
}
1037
1542
int ret = start_mandos_communication(ip, (in_port_t)port,
1038
1543
interface,
1039
avahi_proto_to_af(proto));
1544
avahi_proto_to_af(proto),
1545
mc);
1040
1546
if(ret == 0){
1041
avahi_simple_poll_quit(mc.simple_poll);
1547
avahi_simple_poll_quit(simple_poll);
1042
1548
} else {
1043
1549
if(not add_server(ip, (in_port_t)port, interface,
1044
avahi_proto_to_af(proto))){
1550
avahi_proto_to_af(proto),
1551
&((mandos_context*)mc)->current_server)){
1045
1552
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1046
1553
" list\n", name);
1047
1554
}
1060
1567
const char *domain,
1061
1568
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1062
1569
flags,
1063
AVAHI_GCC_UNUSED void* userdata){
1570
void *mc){
1064
1571
if(b == NULL){
1065
1572
return;
1066
1573
}
1077
1584
case AVAHI_BROWSER_FAILURE:
1078
1585
1079
1586
fprintf_plus(stderr, "(Avahi browser) %s\n",
1080
avahi_strerror(avahi_server_errno(mc.server)));
1081
avahi_simple_poll_quit(mc.simple_poll);
1587
avahi_strerror(avahi_server_errno
1588
(((mandos_context*)mc)->server)));
1589
avahi_simple_poll_quit(simple_poll);
1082
1590
return;
1083
1591
1084
1592
case AVAHI_BROWSER_NEW:
1087
1595
the callback function is called the Avahi server will free the
1088
1596
resolver for us. */
1089
1597
1090
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1091
name, type, domain, protocol, 0,
1092
resolve_callback, NULL) == NULL)
1598
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1599
interface, protocol, name, type,
1600
domain, protocol, 0,
1601
resolve_callback, mc) == NULL)
1093
1602
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1094
1603
" %s\n", name,
1095
avahi_strerror(avahi_server_errno(mc.server)));
1604
avahi_strerror(avahi_server_errno
1605
(((mandos_context*)mc)->server)));
1096
1606
break;
1097
1607
1098
1608
case AVAHI_BROWSER_REMOVE:
1117
1627
signal_received = sig;
1118
1628
int old_errno = errno;
1119
1629
/* set main loop to exit */
1120
if(mc.simple_poll != NULL){
1121
avahi_simple_poll_quit(mc.simple_poll);
1630
if(simple_poll != NULL){
1631
avahi_simple_poll_quit(simple_poll);
1122
1632
}
1123
1633
errno = old_errno;
1124
1634
}
1125
1635
1636
__attribute__((nonnull, warn_unused_result))
1126
1637
bool get_flags(const char *ifname, struct ifreq *ifr){
1127
1638
int ret;
1128
error_t ret_errno;
1639
int old_errno;
1129
1640
1130
1641
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1131
1642
if(s < 0){
1132
ret_errno = errno;
1643
old_errno = errno;
1133
1644
perror_plus("socket");
1134
errno = ret_errno;
1645
errno = old_errno;
1135
1646
return false;
1136
1647
}
1137
strcpy(ifr->ifr_name, ifname);
1648
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1649
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1138
1650
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1139
1651
if(ret == -1){
1140
1652
if(debug){
1141
ret_errno = errno;
1653
old_errno = errno;
1142
1654
perror_plus("ioctl SIOCGIFFLAGS");
1143
errno = ret_errno;
1655
errno = old_errno;
1144
1656
}
1145
1657
return false;
1146
1658
}
1147
1659
return true;
1148
1660
}
1149
1661
1662
__attribute__((nonnull, warn_unused_result))
1150
1663
bool good_flags(const char *ifname, const struct ifreq *ifr){
1151
1664
1152
1665
/* Reject the loopback device */
1194
1707
* corresponds to an acceptable network device.
1195
1708
* (This function is passed to scandir(3) as a filter function.)
1196
1709
*/
1710
__attribute__((nonnull, warn_unused_result))
1197
1711
int good_interface(const struct dirent *if_entry){
1198
1712
if(if_entry->d_name[0] == '.'){
1199
1713
return 0;
1217
1731
/*
1218
1732
* This function determines if a network interface is up.
1219
1733
*/
1734
__attribute__((nonnull, warn_unused_result))
1220
1735
bool interface_is_up(const char *interface){
1221
1736
struct ifreq ifr;
1222
1737
if(not get_flags(interface, &ifr)){
1233
1748
/*
1234
1749
* This function determines if a network interface is running
1235
1750
*/
1751
__attribute__((nonnull, warn_unused_result))
1236
1752
bool interface_is_running(const char *interface){
1237
1753
struct ifreq ifr;
1238
1754
if(not get_flags(interface, &ifr)){
1246
1762
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1247
1763
}
1248
1764
1765
__attribute__((nonnull, pure, warn_unused_result))
1249
1766
int notdotentries(const struct dirent *direntry){
1250
1767
/* Skip "." and ".." */
1251
1768
if(direntry->d_name[0] == '.'
1258
1775
}
1259
1776
1260
1777
/* Is this directory entry a runnable program? */
1778
__attribute__((nonnull, warn_unused_result))
1261
1779
int runnable_hook(const struct dirent *direntry){
1262
1780
int ret;
1263
1781
size_t sret;
1271
1789
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1272
1790
"abcdefghijklmnopqrstuvwxyz"
1273
1791
"0123456789"
1274
"_-");
1792
"_.-");
1275
1793
if((direntry->d_name)[sret] != '\0'){
1276
1794
/* Contains non-allowed characters */
1277
1795
if(debug){
1281
1799
return 0;
1282
1800
}
1283
1801
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);
1802
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1292
1803
if(ret == -1){
1293
1804
if(debug){
1294
1805
perror_plus("Could not stat hook");
1318
1829
return 1;
1319
1830
}
1320
1831
1321
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1832
__attribute__((nonnull, warn_unused_result))
1833
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1834
mandos_context *mc){
1322
1835
int ret;
1323
1836
struct timespec now;
1324
1837
struct timespec waited_time;
1325
1838
intmax_t block_time;
1326
1839
1327
1840
while(true){
1328
if(mc.current_server == NULL){
1329
if (debug){
1841
if(mc->current_server == NULL){
1842
if(debug){
1330
1843
fprintf_plus(stderr, "Wait until first server is found."
1331
1844
" No timeout!\n");
1332
1845
}
1333
1846
ret = avahi_simple_poll_iterate(s, -1);
1334
1847
} else {
1335
if (debug){
1848
if(debug){
1336
1849
fprintf_plus(stderr, "Check current_server if we should run"
1337
1850
" it, or wait\n");
1338
1851
}
1345
1858
/* Calculating in ms how long time between now and server
1346
1859
who we visted longest time ago. Now - last seen. */
1347
1860
waited_time.tv_sec = (now.tv_sec
1348
- mc.current_server->last_seen.tv_sec);
1861
- mc->current_server->last_seen.tv_sec);
1349
1862
waited_time.tv_nsec = (now.tv_nsec
1350
- mc.current_server->last_seen.tv_nsec);
1863
- mc->current_server->last_seen.tv_nsec);
1351
1864
/* total time is 10s/10,000ms.
1352
1865
Converting to s from ms by dividing by 1,000,
1353
1866
and ns to ms by dividing by 1,000,000. */
1355
1868
- ((intmax_t)waited_time.tv_sec * 1000))
1356
1869
- ((intmax_t)waited_time.tv_nsec / 1000000));
1357
1870
1358
if (debug){
1871
if(debug){
1359
1872
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1360
1873
block_time);
1361
1874
}
1362
1875
1363
1876
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);
1877
ret = start_mandos_communication(mc->current_server->ip,
1878
mc->current_server->port,
1879
mc->current_server->if_index,
1880
mc->current_server->af, mc);
1368
1881
if(ret == 0){
1369
avahi_simple_poll_quit(mc.simple_poll);
1882
avahi_simple_poll_quit(s);
1370
1883
return 0;
1371
1884
}
1372
1885
ret = clock_gettime(CLOCK_MONOTONIC,
1373
&mc.current_server->last_seen);
1886
&mc->current_server->last_seen);
1374
1887
if(ret == -1){
1375
1888
perror_plus("clock_gettime");
1376
1889
return -1;
1377
1890
}
1378
mc.current_server = mc.current_server->next;
1891
mc->current_server = mc->current_server->next;
1379
1892
block_time = 0; /* Call avahi to find new Mandos
1380
1893
servers, but don't block */
1381
1894
}
1383
1896
ret = avahi_simple_poll_iterate(s, (int)block_time);
1384
1897
}
1385
1898
if(ret != 0){
1386
if (ret > 0 or errno != EINTR){
1899
if(ret > 0 or errno != EINTR){
1387
1900
return (ret != 1) ? ret : 0;
1388
1901
}
1389
1902
}
1390
1903
}
1391
1904
}
1392
1905
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,
1906
__attribute__((nonnull))
1907
void run_network_hooks(const char *mode, const char *interface,
1446
1908
const float delay){
1447
struct dirent **direntries;
1909
struct dirent **direntries = NULL;
1910
if(hookdir_fd == -1){
1911
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1912
| O_CLOEXEC);
1913
if(hookdir_fd == -1){
1914
if(errno == ENOENT){
1915
if(debug){
1916
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1917
" found\n", hookdir);
1918
}
1919
} else {
1920
perror_plus("open");
1921
}
1922
return;
1923
}
1924
}
1925
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1926
runnable_hook, alphasort);
1927
if(numhooks == -1){
1928
perror_plus("scandir");
1929
return;
1930
}
1448
1931
struct dirent *direntry;
1449
1932
int ret;
1450
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1451
alphasort);
1452
if(numhooks == -1){
1453
if(errno == ENOENT){
1454
if(debug){
1455
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1456
" found\n", hookdir);
1457
}
1458
} else {
1459
perror_plus("scandir");
1933
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1934
if(devnull == -1){
1935
perror_plus("open(\"/dev/null\", O_RDONLY)");
1936
return;
1937
}
1938
for(int i = 0; i < numhooks; i++){
1939
direntry = direntries[i];
1940
if(debug){
1941
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1942
direntry->d_name);
1460
1943
}
1461
} else {
1462
int devnull = open("/dev/null", O_RDONLY);
1463
for(int i = 0; i < numhooks; i++){
1464
direntry = direntries[i];
1465
char *fullname = NULL;
1466
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1467
if(ret < 0){
1944
pid_t hook_pid = fork();
1945
if(hook_pid == 0){
1946
/* Child */
1947
/* Raise privileges */
1948
errno = raise_privileges_permanently();
1949
if(errno != 0){
1950
perror_plus("Failed to raise privileges");
1951
_exit(EX_NOPERM);
1952
}
1953
/* Set group */
1954
errno = 0;
1955
ret = setgid(0);
1956
if(ret == -1){
1957
perror_plus("setgid");
1958
_exit(EX_NOPERM);
1959
}
1960
/* Reset supplementary groups */
1961
errno = 0;
1962
ret = setgroups(0, NULL);
1963
if(ret == -1){
1964
perror_plus("setgroups");
1965
_exit(EX_NOPERM);
1966
}
1967
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1968
if(ret == -1){
1969
perror_plus("setenv");
1970
_exit(EX_OSERR);
1971
}
1972
ret = setenv("DEVICE", interface, 1);
1973
if(ret == -1){
1974
perror_plus("setenv");
1975
_exit(EX_OSERR);
1976
}
1977
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1978
if(ret == -1){
1979
perror_plus("setenv");
1980
_exit(EX_OSERR);
1981
}
1982
ret = setenv("MODE", mode, 1);
1983
if(ret == -1){
1984
perror_plus("setenv");
1985
_exit(EX_OSERR);
1986
}
1987
char *delaystring;
1988
ret = asprintf(&delaystring, "%f", (double)delay);
1989
if(ret == -1){
1468
1990
perror_plus("asprintf");
1469
continue;
1470
}
1471
if(debug){
1472
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1473
direntry->d_name);
1474
}
1475
pid_t hook_pid = fork();
1476
if(hook_pid == 0){
1477
/* Child */
1478
/* Raise privileges */
1479
raise_privileges_permanently();
1480
/* Set group */
1481
errno = 0;
1482
ret = setgid(0);
1483
if(ret == -1){
1484
perror_plus("setgid");
1485
}
1486
/* Reset supplementary groups */
1487
errno = 0;
1488
ret = setgroups(0, NULL);
1489
if(ret == -1){
1490
perror_plus("setgroups");
1491
}
1492
dup2(devnull, STDIN_FILENO);
1493
close(devnull);
1494
dup2(STDERR_FILENO, STDOUT_FILENO);
1495
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1496
if(ret == -1){
1497
perror_plus("setenv");
1498
_exit(EX_OSERR);
1499
}
1500
ret = setenv("DEVICE", interface, 1);
1501
if(ret == -1){
1502
perror_plus("setenv");
1503
_exit(EX_OSERR);
1504
}
1505
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1506
if(ret == -1){
1507
perror_plus("setenv");
1508
_exit(EX_OSERR);
1509
}
1510
ret = setenv("MODE", mode, 1);
1511
if(ret == -1){
1512
perror_plus("setenv");
1513
_exit(EX_OSERR);
1514
}
1515
char *delaystring;
1516
ret = asprintf(&delaystring, "%f", delay);
1517
if(ret == -1){
1518
perror_plus("asprintf");
1519
_exit(EX_OSERR);
1520
}
1521
ret = setenv("DELAY", delaystring, 1);
1522
if(ret == -1){
1523
free(delaystring);
1524
perror_plus("setenv");
1525
_exit(EX_OSERR);
1526
}
1991
_exit(EX_OSERR);
1992
}
1993
ret = setenv("DELAY", delaystring, 1);
1994
if(ret == -1){
1527
1995
free(delaystring);
1528
if(connect_to != NULL){
1529
ret = setenv("CONNECT", connect_to, 1);
1530
if(ret == -1){
1531
perror_plus("setenv");
1532
_exit(EX_OSERR);
1533
}
1534
}
1535
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1536
perror_plus("execl");
1537
_exit(EXIT_FAILURE);
1538
}
1996
perror_plus("setenv");
1997
_exit(EX_OSERR);
1998
}
1999
free(delaystring);
2000
if(connect_to != NULL){
2001
ret = setenv("CONNECT", connect_to, 1);
2002
if(ret == -1){
2003
perror_plus("setenv");
2004
_exit(EX_OSERR);
2005
}
2006
}
2007
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2008
direntry->d_name,
2009
O_RDONLY));
2010
if(hook_fd == -1){
2011
perror_plus("openat");
2012
_exit(EXIT_FAILURE);
2013
}
2014
if(close(hookdir_fd) == -1){
2015
perror_plus("close");
2016
_exit(EXIT_FAILURE);
2017
}
2018
ret = dup2(devnull, STDIN_FILENO);
2019
if(ret == -1){
2020
perror_plus("dup2(devnull, STDIN_FILENO)");
2021
_exit(EX_OSERR);
2022
}
2023
ret = close(devnull);
2024
if(ret == -1){
2025
perror_plus("close");
2026
_exit(EX_OSERR);
2027
}
2028
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2029
if(ret == -1){
2030
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2031
_exit(EX_OSERR);
2032
}
2033
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2034
environ) == -1){
2035
perror_plus("fexecve");
2036
_exit(EXIT_FAILURE);
2037
}
2038
} else {
2039
if(hook_pid == -1){
2040
perror_plus("fork");
2041
free(direntry);
2042
continue;
2043
}
2044
int status;
2045
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2046
perror_plus("waitpid");
2047
free(direntry);
2048
continue;
2049
}
2050
if(WIFEXITED(status)){
2051
if(WEXITSTATUS(status) != 0){
2052
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2053
" with status %d\n", direntry->d_name,
2054
WEXITSTATUS(status));
2055
free(direntry);
2056
continue;
2057
}
2058
} else if(WIFSIGNALED(status)){
2059
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2060
" signal %d\n", direntry->d_name,
2061
WTERMSIG(status));
2062
free(direntry);
2063
continue;
1539
2064
} else {
1540
int status;
1541
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1542
perror_plus("waitpid");
1543
free(fullname);
1544
continue;
1545
}
1546
if(WIFEXITED(status)){
1547
if(WEXITSTATUS(status) != 0){
1548
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1549
" with status %d\n", direntry->d_name,
1550
WEXITSTATUS(status));
1551
free(fullname);
1552
continue;
1553
}
1554
} else if(WIFSIGNALED(status)){
1555
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1556
" signal %d\n", direntry->d_name,
1557
WTERMSIG(status));
1558
free(fullname);
1559
continue;
1560
} else {
1561
fprintf_plus(stderr, "Warning: network hook \"%s\""
1562
" crashed\n", direntry->d_name);
1563
free(fullname);
1564
continue;
1565
}
1566
}
1567
free(fullname);
1568
if(debug){
1569
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1570
direntry->d_name);
1571
}
1572
}
1573
close(devnull);
1574
}
1575
return true;
2065
fprintf_plus(stderr, "Warning: network hook \"%s\""
2066
" crashed\n", direntry->d_name);
2067
free(direntry);
2068
continue;
2069
}
2070
}
2071
if(debug){
2072
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2073
direntry->d_name);
2074
}
2075
free(direntry);
2076
}
2077
free(direntries);
2078
if(close(hookdir_fd) == -1){
2079
perror_plus("close");
2080
} else {
2081
hookdir_fd = -1;
2082
}
2083
close(devnull);
1576
2084
}
1577
2085
1578
error_t bring_up_interface(const char *const interface,
1579
const float delay){
1580
int sd = -1;
1581
error_t old_errno = errno;
1582
error_t ret_errno = 0;
1583
int ret, ret_setflags;
2086
__attribute__((nonnull, warn_unused_result))
2087
int bring_up_interface(const char *const interface,
2088
const float delay){
2089
int old_errno = errno;
2090
int ret;
1584
2091
struct ifreq network;
1585
2092
unsigned int if_index = if_nametoindex(interface);
1586
2093
if(if_index == 0){
1595
2102
}
1596
2103
1597
2104
if(not interface_is_up(interface)){
1598
if(not get_flags(interface, &network) and debug){
2105
int ret_errno = 0;
2106
int ioctl_errno = 0;
2107
if(not get_flags(interface, &network)){
1599
2108
ret_errno = errno;
1600
2109
fprintf_plus(stderr, "Failed to get flags for interface "
1601
2110
"\"%s\"\n", interface);
2111
errno = old_errno;
1602
2112
return ret_errno;
1603
2113
}
1604
network.ifr_flags |= IFF_UP;
2114
network.ifr_flags |= IFF_UP; /* set flag */
1605
2115
1606
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1607
if(sd < 0){
2116
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2117
if(sd == -1){
1608
2118
ret_errno = errno;
1609
2119
perror_plus("socket");
1610
2120
errno = old_errno;
1611
2121
return ret_errno;
1612
2122
}
1613
2123
1614
2124
if(quit_now){
1615
close(sd);
2125
ret = close(sd);
2126
if(ret == -1){
2127
perror_plus("close");
2128
}
1616
2129
errno = old_errno;
1617
2130
return EINTR;
1618
2131
}
1622
2135
interface);
1623
2136
}
1624
2137
1625
/* Raise priviliges */
1626
raise_privileges();
2138
/* Raise privileges */
2139
ret_errno = raise_privileges();
2140
if(ret_errno != 0){
2141
errno = ret_errno;
2142
perror_plus("Failed to raise privileges");
2143
}
1627
2144
1628
2145
#ifdef __linux__
1629
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1630
messages about the network interface to mess up the prompt */
1631
int ret_linux = klogctl(8, NULL, 5);
1632
bool restore_loglevel = true;
1633
if(ret_linux == -1){
1634
restore_loglevel = false;
1635
perror_plus("klogctl");
2146
int ret_linux;
2147
bool restore_loglevel = false;
2148
if(ret_errno == 0){
2149
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2150
messages about the network interface to mess up the prompt */
2151
ret_linux = klogctl(8, NULL, 5);
2152
if(ret_linux == -1){
2153
perror_plus("klogctl");
2154
} else {
2155
restore_loglevel = true;
2156
}
1636
2157
}
1637
2158
#endif /* __linux__ */
1638
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1639
ret_errno = errno;
2159
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2160
ioctl_errno = errno;
1640
2161
#ifdef __linux__
1641
2162
if(restore_loglevel){
1642
2163
ret_linux = klogctl(7, NULL, 0);
1646
2167
}
1647
2168
#endif /* __linux__ */
1648
2169
1649
/* Lower privileges */
1650
lower_privileges();
2170
/* If raise_privileges() succeeded above */
2171
if(ret_errno == 0){
2172
/* Lower privileges */
2173
ret_errno = lower_privileges();
2174
if(ret_errno != 0){
2175
errno = ret_errno;
2176
perror_plus("Failed to lower privileges");
2177
}
2178
}
1651
2179
1652
2180
/* Close the socket */
1653
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2181
ret = close(sd);
1654
2182
if(ret == -1){
1655
2183
perror_plus("close");
1656
2184
}
1657
2185
1658
2186
if(ret_setflags == -1){
1659
errno = ret_errno;
2187
errno = ioctl_errno;
1660
2188
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1661
2189
errno = old_errno;
1662
return ret_errno;
2190
return ioctl_errno;
1663
2191
}
1664
2192
} else if(debug){
1665
2193
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1683
2211
return 0;
1684
2212
}
1685
2213
1686
error_t take_down_interface(const char *const interface){
1687
int sd = -1;
1688
error_t old_errno = errno;
1689
error_t ret_errno = 0;
1690
int ret, ret_setflags;
2214
__attribute__((nonnull, warn_unused_result))
2215
int take_down_interface(const char *const interface){
2216
int old_errno = errno;
1691
2217
struct ifreq network;
1692
2218
unsigned int if_index = if_nametoindex(interface);
1693
2219
if(if_index == 0){
1696
2222
return ENXIO;
1697
2223
}
1698
2224
if(interface_is_up(interface)){
2225
int ret_errno = 0;
2226
int ioctl_errno = 0;
1699
2227
if(not get_flags(interface, &network) and debug){
1700
2228
ret_errno = errno;
1701
2229
fprintf_plus(stderr, "Failed to get flags for interface "
1702
2230
"\"%s\"\n", interface);
2231
errno = old_errno;
1703
2232
return ret_errno;
1704
2233
}
1705
2234
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1706
2235
1707
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1708
if(sd < 0){
2236
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2237
if(sd == -1){
1709
2238
ret_errno = errno;
1710
2239
perror_plus("socket");
1711
2240
errno = old_errno;
1717
2246
interface);
1718
2247
}
1719
2248
1720
/* Raise priviliges */
1721
raise_privileges();
1722
1723
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1724
ret_errno = errno;
1725
1726
/* Lower privileges */
1727
lower_privileges();
2249
/* Raise privileges */
2250
ret_errno = raise_privileges();
2251
if(ret_errno != 0){
2252
errno = ret_errno;
2253
perror_plus("Failed to raise privileges");
2254
}
2255
2256
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2257
ioctl_errno = errno;
2258
2259
/* If raise_privileges() succeeded above */
2260
if(ret_errno == 0){
2261
/* Lower privileges */
2262
ret_errno = lower_privileges();
2263
if(ret_errno != 0){
2264
errno = ret_errno;
2265
perror_plus("Failed to lower privileges");
2266
}
2267
}
1728
2268
1729
2269
/* Close the socket */
1730
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2270
int ret = close(sd);
1731
2271
if(ret == -1){
1732
2272
perror_plus("close");
1733
2273
}
1734
2274
1735
2275
if(ret_setflags == -1){
1736
errno = ret_errno;
2276
errno = ioctl_errno;
1737
2277
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1738
2278
errno = old_errno;
1739
return ret_errno;
2279
return ioctl_errno;
1740
2280
}
1741
2281
} else if(debug){
1742
2282
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1748
2288
}
1749
2289
1750
2290
int main(int argc, char *argv[]){
2291
mandos_context mc = { .server = NULL, .dh_bits = 0,
2292
.priority = "SECURE256:!CTYPE-X.509"
2293
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2294
.current_server = NULL, .interfaces = NULL,
2295
.interfaces_size = 0 };
1751
2296
AvahiSServiceBrowser *sb = NULL;
1752
2297
error_t ret_errno;
1753
2298
int ret;
1754
2299
intmax_t tmpmax;
1755
2300
char *tmp;
1756
2301
int exitcode = EXIT_SUCCESS;
1757
char *interfaces = NULL;
1758
size_t interfaces_size = 0;
1759
2302
char *interfaces_to_take_down = NULL;
1760
2303
size_t interfaces_to_take_down_size = 0;
1761
char tempdir[] = "/tmp/mandosXXXXXX";
1762
bool tempdir_created = false;
2304
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2305
char old_tempdir[] = "/tmp/mandosXXXXXX";
2306
char *tempdir = NULL;
1763
2307
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1764
2308
const char *seckey = PATHDIR "/" SECKEY;
1765
2309
const char *pubkey = PATHDIR "/" PUBKEY;
2310
const char *dh_params_file = NULL;
1766
2311
char *interfaces_hooks = NULL;
1767
size_t interfaces_hooks_size = 0;
1768
2312
1769
2313
bool gnutls_initialized = false;
1770
2314
bool gpgme_initialized = false;
1822
2366
.doc = "Bit length of the prime number used in the"
1823
2367
" Diffie-Hellman key exchange",
1824
2368
.group = 2 },
2369
{ .name = "dh-params", .key = 134,
2370
.arg = "FILE",
2371
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2372
" for the Diffie-Hellman key exchange",
2373
.group = 2 },
1825
2374
{ .name = "priority", .key = 130,
1826
2375
.arg = "STRING",
1827
2376
.doc = "GnuTLS priority string for the TLS handshake",
1861
2410
connect_to = arg;
1862
2411
break;
1863
2412
case 'i': /* --interface */
1864
ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,
1865
(int)',');
2413
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2414
arg, (int)',');
1866
2415
if(ret_errno != 0){
1867
2416
argp_error(state, "%s", strerror(ret_errno));
1868
2417
}
1882
2431
}
1883
2432
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1884
2433
break;
2434
case 134: /* --dh-params */
2435
dh_params_file = arg;
2436
break;
1885
2437
case 130: /* --priority */
1886
2438
mc.priority = arg;
1887
2439
break;
1927
2479
.args_doc = "",
1928
2480
.doc = "Mandos client -- Get and decrypt"
1929
2481
" passwords from a Mandos server" };
1930
ret = argp_parse(&argp, argc, argv,
1931
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1932
switch(ret){
2482
ret_errno = argp_parse(&argp, argc, argv,
2483
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2484
switch(ret_errno){
1933
2485
case 0:
1934
2486
break;
1935
2487
case ENOMEM:
1936
2488
default:
1937
errno = ret;
2489
errno = ret_errno;
1938
2490
perror_plus("argp_parse");
1939
2491
exitcode = EX_OSERR;
1940
2492
goto end;
1943
2495
goto end;
1944
2496
}
1945
2497
}
1946
2498
1947
2499
{
1948
2500
/* Work around Debian bug #633582:
1949
<http://bugs.debian.org/633582> */
2501
<https://bugs.debian.org/633582> */
1950
2502
1951
/* Re-raise priviliges */
1952
if(raise_privileges() == 0){
2503
/* Re-raise privileges */
2504
ret = raise_privileges();
2505
if(ret != 0){
2506
errno = ret;
2507
perror_plus("Failed to raise privileges");
2508
} else {
1953
2509
struct stat st;
1954
2510
1955
2511
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1969
2525
}
1970
2526
}
1971
2527
}
1972
TEMP_FAILURE_RETRY(close(seckey_fd));
2528
close(seckey_fd);
1973
2529
}
1974
2530
}
1975
2531
1976
2532
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1977
2533
int pubkey_fd = open(pubkey, O_RDONLY);
1978
2534
if(pubkey_fd == -1){
1990
2546
}
1991
2547
}
1992
2548
}
1993
TEMP_FAILURE_RETRY(close(pubkey_fd));
1994
}
1995
}
1996
2549
close(pubkey_fd);
2550
}
2551
}
2552
2553
if(dh_params_file != NULL
2554
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2555
int dhparams_fd = open(dh_params_file, O_RDONLY);
2556
if(dhparams_fd == -1){
2557
perror_plus("open");
2558
} else {
2559
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2560
if(ret == -1){
2561
perror_plus("fstat");
2562
} else {
2563
if(S_ISREG(st.st_mode)
2564
and st.st_uid == 0 and st.st_gid == 0){
2565
ret = fchown(dhparams_fd, uid, gid);
2566
if(ret == -1){
2567
perror_plus("fchown");
2568
}
2569
}
2570
}
2571
close(dhparams_fd);
2572
}
2573
}
2574
1997
2575
/* Lower privileges */
1998
errno = 0;
1999
ret = seteuid(uid);
2000
if(ret == -1){
2001
perror_plus("seteuid");
2576
ret = lower_privileges();
2577
if(ret != 0){
2578
errno = ret;
2579
perror_plus("Failed to lower privileges");
2002
2580
}
2003
2581
}
2004
2582
}
2005
2583
2006
/* Remove empty interface names */
2584
/* Remove invalid interface names (except "none") */
2007
2585
{
2008
2586
char *interface = NULL;
2009
while((interface = argz_next(interfaces, interfaces_size,
2587
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2010
2588
interface))){
2011
if(if_nametoindex(interface) == 0){
2012
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2589
if(strcmp(interface, "none") != 0
2590
and if_nametoindex(interface) == 0){
2591
if(interface[0] != '\0'){
2013
2592
fprintf_plus(stderr, "Not using nonexisting interface"
2014
2593
" \"%s\"\n", interface);
2015
2594
}
2016
argz_delete(&interfaces, &interfaces_size, interface);
2595
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2017
2596
interface = NULL;
2018
2597
}
2019
2598
}
2021
2600
2022
2601
/* Run network hooks */
2023
2602
{
2024
2025
if(interfaces != NULL){
2026
interfaces_hooks = malloc(interfaces_size);
2603
if(mc.interfaces != NULL){
2604
interfaces_hooks = malloc(mc.interfaces_size);
2027
2605
if(interfaces_hooks == NULL){
2028
2606
perror_plus("malloc");
2029
2607
goto end;
2030
2608
}
2031
memcpy(interfaces_hooks, interfaces, interfaces_size);
2032
interfaces_hooks_size = interfaces_size;
2033
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2034
(int)',');
2035
}
2036
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2037
interfaces_hooks : "", delay)){
2038
goto end;
2039
}
2609
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2610
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2611
}
2612
run_network_hooks("start", interfaces_hooks != NULL ?
2613
interfaces_hooks : "", delay);
2040
2614
}
2041
2615
2042
2616
if(not debug){
2047
2621
from the signal handler */
2048
2622
/* Initialize the pseudo-RNG for Avahi */
2049
2623
srand((unsigned int) time(NULL));
2050
mc.simple_poll = avahi_simple_poll_new();
2051
if(mc.simple_poll == NULL){
2624
simple_poll = avahi_simple_poll_new();
2625
if(simple_poll == NULL){
2052
2626
fprintf_plus(stderr,
2053
2627
"Avahi: Failed to create simple poll object.\n");
2054
2628
exitcode = EX_UNAVAILABLE;
2119
2693
}
2120
2694
2121
2695
/* If no interfaces were specified, make a list */
2122
if(interfaces == NULL){
2123
struct dirent **direntries;
2696
if(mc.interfaces == NULL){
2697
struct dirent **direntries = NULL;
2124
2698
/* Look for any good interfaces */
2125
2699
ret = scandir(sys_class_net, &direntries, good_interface,
2126
2700
alphasort);
2127
2701
if(ret >= 1){
2128
2702
/* Add all found interfaces to interfaces list */
2129
2703
for(int i = 0; i < ret; ++i){
2130
ret_errno = argz_add(&interfaces, &interfaces_size,
2704
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2131
2705
direntries[i]->d_name);
2132
2706
if(ret_errno != 0){
2707
errno = ret_errno;
2133
2708
perror_plus("argz_add");
2709
free(direntries[i]);
2134
2710
continue;
2135
2711
}
2136
2712
if(debug){
2137
2713
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2138
2714
direntries[i]->d_name);
2139
2715
}
2716
free(direntries[i]);
2140
2717
}
2141
2718
free(direntries);
2142
2719
} else {
2143
free(direntries);
2720
if(ret == 0){
2721
free(direntries);
2722
}
2144
2723
fprintf_plus(stderr, "Could not find a network interface\n");
2145
2724
exitcode = EXIT_FAILURE;
2146
2725
goto end;
2147
2726
}
2148
2727
}
2149
2728
2150
/* If we only got one interface, explicitly use only that one */
2151
if(argz_count(interfaces, interfaces_size) == 1){
2152
if(debug){
2153
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2154
interfaces);
2155
}
2156
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2157
}
2158
2159
/* Bring up interfaces which are down */
2160
if(not (argz_count(interfaces, interfaces_size) == 1
2161
and strcmp(interfaces, "none") == 0)){
2729
/* Bring up interfaces which are down, and remove any "none"s */
2730
{
2162
2731
char *interface = NULL;
2163
while((interface = argz_next(interfaces, interfaces_size,
2732
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2164
2733
interface))){
2734
/* If interface name is "none", stop bringing up interfaces.
2735
Also remove all instances of "none" from the list */
2736
if(strcmp(interface, "none") == 0){
2737
argz_delete(&mc.interfaces, &mc.interfaces_size,
2738
interface);
2739
interface = NULL;
2740
while((interface = argz_next(mc.interfaces,
2741
mc.interfaces_size, interface))){
2742
if(strcmp(interface, "none") == 0){
2743
argz_delete(&mc.interfaces, &mc.interfaces_size,
2744
interface);
2745
interface = NULL;
2746
}
2747
}
2748
break;
2749
}
2165
2750
bool interface_was_up = interface_is_up(interface);
2166
ret = bring_up_interface(interface, delay);
2751
errno = bring_up_interface(interface, delay);
2167
2752
if(not interface_was_up){
2168
if(ret != 0){
2169
errno = ret;
2170
perror_plus("Failed to bring up interface");
2753
if(errno != 0){
2754
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2755
" %s\n", interface, strerror(errno));
2171
2756
} else {
2172
ret_errno = argz_add(&interfaces_to_take_down,
2173
&interfaces_to_take_down_size,
2174
interface);
2757
errno = argz_add(&interfaces_to_take_down,
2758
&interfaces_to_take_down_size,
2759
interface);
2760
if(errno != 0){
2761
perror_plus("argz_add");
2762
}
2175
2763
}
2176
2764
}
2177
2765
}
2178
free(interfaces);
2179
interfaces = NULL;
2180
interfaces_size = 0;
2181
2766
if(debug and (interfaces_to_take_down == NULL)){
2182
2767
fprintf_plus(stderr, "No interfaces were brought up\n");
2183
2768
}
2184
2769
}
2185
2770
2771
/* If we only got one interface, explicitly use only that one */
2772
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2773
if(debug){
2774
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2775
mc.interfaces);
2776
}
2777
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2778
}
2779
2186
2780
if(quit_now){
2187
2781
goto end;
2188
2782
}
2189
2783
2190
ret = init_gnutls_global(pubkey, seckey);
2784
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2191
2785
if(ret == -1){
2192
2786
fprintf_plus(stderr, "init_gnutls_global failed\n");
2193
2787
exitcode = EX_UNAVAILABLE;
2200
2794
goto end;
2201
2795
}
2202
2796
2203
if(mkdtemp(tempdir) == NULL){
2797
/* Try /run/tmp before /tmp */
2798
tempdir = mkdtemp(run_tempdir);
2799
if(tempdir == NULL and errno == ENOENT){
2800
if(debug){
2801
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2802
run_tempdir, old_tempdir);
2803
}
2804
tempdir = mkdtemp(old_tempdir);
2805
}
2806
if(tempdir == NULL){
2204
2807
perror_plus("mkdtemp");
2205
2808
goto end;
2206
2809
}
2207
tempdir_created = true;
2208
2810
2209
2811
if(quit_now){
2210
2812
goto end;
2211
2813
}
2212
2814
2213
if(not init_gpgme(pubkey, seckey, tempdir)){
2815
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2214
2816
fprintf_plus(stderr, "init_gpgme failed\n");
2215
2817
exitcode = EX_UNAVAILABLE;
2216
2818
goto end;
2246
2848
exitcode = EX_USAGE;
2247
2849
goto end;
2248
2850
}
2249
2851
2250
2852
if(quit_now){
2251
2853
goto end;
2252
2854
}
2273
2875
}
2274
2876
2275
2877
while(not quit_now){
2276
ret = start_mandos_communication(address, port, if_index, af);
2878
ret = start_mandos_communication(address, port, if_index, af,
2879
&mc);
2277
2880
if(quit_now or ret == 0){
2278
2881
break;
2279
2882
}
2281
2884
fprintf_plus(stderr, "Retrying in %d seconds\n",
2282
2885
(int)retry_interval);
2283
2886
}
2284
sleep((int)retry_interval);
2887
sleep((unsigned int)retry_interval);
2285
2888
}
2286
2889
2287
if (not quit_now){
2890
if(not quit_now){
2288
2891
exitcode = EXIT_SUCCESS;
2289
2892
}
2290
2893
2305
2908
config.publish_domain = 0;
2306
2909
2307
2910
/* Allocate a new server */
2308
mc.server = avahi_server_new(avahi_simple_poll_get
2309
(mc.simple_poll), &config, NULL,
2310
NULL, &ret_errno);
2911
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2912
&config, NULL, NULL, &ret);
2311
2913
2312
2914
/* Free the Avahi configuration data */
2313
2915
avahi_server_config_free(&config);
2316
2918
/* Check if creating the Avahi server object succeeded */
2317
2919
if(mc.server == NULL){
2318
2920
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2319
avahi_strerror(ret_errno));
2921
avahi_strerror(ret));
2320
2922
exitcode = EX_UNAVAILABLE;
2321
2923
goto end;
2322
2924
}
2328
2930
/* Create the Avahi service browser */
2329
2931
sb = avahi_s_service_browser_new(mc.server, if_index,
2330
2932
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2331
NULL, 0, browse_callback, NULL);
2933
NULL, 0, browse_callback,
2934
(void *)&mc);
2332
2935
if(sb == NULL){
2333
2936
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2334
2937
avahi_strerror(avahi_server_errno(mc.server)));
2345
2948
if(debug){
2346
2949
fprintf_plus(stderr, "Starting Avahi loop search\n");
2347
2950
}
2348
2349
ret = avahi_loop_with_timeout(mc.simple_poll,
2350
(int)(retry_interval * 1000));
2951
2952
ret = avahi_loop_with_timeout(simple_poll,
2953
(int)(retry_interval * 1000), &mc);
2351
2954
if(debug){
2352
2955
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2353
2956
(ret == 0) ? "successfully" : "with error");
2356
2959
end:
2357
2960
2358
2961
if(debug){
2359
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2962
if(signal_received){
2963
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
2964
argv[0], signal_received,
2965
strsignal(signal_received));
2966
} else {
2967
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2968
}
2360
2969
}
2361
2970
2362
2971
/* Cleanup things */
2972
free(mc.interfaces);
2973
2363
2974
if(sb != NULL)
2364
2975
avahi_s_service_browser_free(sb);
2365
2976
2366
2977
if(mc.server != NULL)
2367
2978
avahi_server_free(mc.server);
2368
2979
2369
if(mc.simple_poll != NULL)
2370
avahi_simple_poll_free(mc.simple_poll);
2980
if(simple_poll != NULL)
2981
avahi_simple_poll_free(simple_poll);
2371
2982
2372
2983
if(gnutls_initialized){
2373
2984
gnutls_certificate_free_credentials(mc.cred);
2374
gnutls_global_deinit();
2375
2985
gnutls_dh_params_deinit(mc.dh_params);
2376
2986
}
2377
2987
2385
2995
mc.current_server->prev->next = NULL;
2386
2996
while(mc.current_server != NULL){
2387
2997
server *next = mc.current_server->next;
2998
#ifdef __GNUC__
2999
#pragma GCC diagnostic push
3000
#pragma GCC diagnostic ignored "-Wcast-qual"
3001
#endif
3002
free((char *)(mc.current_server->ip));
3003
#ifdef __GNUC__
3004
#pragma GCC diagnostic pop
3005
#endif
2388
3006
free(mc.current_server);
2389
3007
mc.current_server = next;
2390
3008
}
2391
3009
}
2392
3010
2393
/* Re-raise priviliges */
3011
/* Re-raise privileges */
2394
3012
{
2395
raise_privileges();
2396
2397
/* Run network hooks */
2398
run_network_hooks("stop", interfaces_hooks != NULL ?
2399
interfaces_hooks : "", delay);
2400
2401
/* Take down the network interfaces which were brought up */
2402
{
2403
char *interface = NULL;
2404
while((interface=argz_next(interfaces_to_take_down,
2405
interfaces_to_take_down_size,
2406
interface))){
2407
ret_errno = take_down_interface(interface);
2408
if(ret_errno != 0){
2409
errno = ret_errno;
2410
perror_plus("Failed to take down interface");
2411
}
2412
}
2413
if(debug and (interfaces_to_take_down == NULL)){
2414
fprintf_plus(stderr, "No interfaces needed to be taken"
2415
" down\n");
2416
}
2417
}
2418
2419
lower_privileges_permanently();
3013
ret = raise_privileges();
3014
if(ret != 0){
3015
errno = ret;
3016
perror_plus("Failed to raise privileges");
3017
} else {
3018
3019
/* Run network hooks */
3020
run_network_hooks("stop", interfaces_hooks != NULL ?
3021
interfaces_hooks : "", delay);
3022
3023
/* Take down the network interfaces which were brought up */
3024
{
3025
char *interface = NULL;
3026
while((interface=argz_next(interfaces_to_take_down,
3027
interfaces_to_take_down_size,
3028
interface))){
3029
ret = take_down_interface(interface);
3030
if(ret != 0){
3031
errno = ret;
3032
perror_plus("Failed to take down interface");
3033
}
3034
}
3035
if(debug and (interfaces_to_take_down == NULL)){
3036
fprintf_plus(stderr, "No interfaces needed to be taken"
3037
" down\n");
3038
}
3039
}
3040
}
3041
3042
ret = lower_privileges_permanently();
3043
if(ret != 0){
3044
errno = ret;
3045
perror_plus("Failed to lower privileges permanently");
3046
}
2420
3047
}
2421
3048
2422
3049
free(interfaces_to_take_down);
2423
3050
free(interfaces_hooks);
2424
3051
3052
void clean_dir_at(int base, const char * const dirname,
3053
uintmax_t level){
3054
struct dirent **direntries = NULL;
3055
int dret;
3056
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3057
O_RDONLY
3058
| O_NOFOLLOW
3059
| O_DIRECTORY
3060
| O_PATH));
3061
if(dir_fd == -1){
3062
perror_plus("open");
3063
}
3064
int numentries = scandirat(dir_fd, ".", &direntries,
3065
notdotentries, alphasort);
3066
if(numentries >= 0){
3067
for(int i = 0; i < numentries; i++){
3068
if(debug){
3069
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3070
dirname, direntries[i]->d_name);
3071
}
3072
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3073
if(dret == -1){
3074
if(errno == EISDIR){
3075
dret = unlinkat(dir_fd, direntries[i]->d_name,
3076
AT_REMOVEDIR);
3077
}
3078
if((dret == -1) and (errno == ENOTEMPTY)
3079
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3080
== 0) and (level == 0)){
3081
/* Recurse only in this special case */
3082
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3083
dret = 0;
3084
}
3085
if(dret == -1){
3086
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3087
direntries[i]->d_name, strerror(errno));
3088
}
3089
}
3090
free(direntries[i]);
3091
}
3092
3093
/* need to clean even if 0 because man page doesn't specify */
3094
free(direntries);
3095
if(numentries == -1){
3096
perror_plus("scandirat");
3097
}
3098
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3099
if(dret == -1 and errno != ENOENT){
3100
perror_plus("rmdir");
3101
}
3102
} else {
3103
perror_plus("scandirat");
3104
}
3105
close(dir_fd);
3106
}
3107
2425
3108
/* Removes the GPGME temp directory and all files inside */
2426
if(tempdir_created){
2427
struct dirent **direntries = NULL;
2428
struct dirent *direntry = NULL;
2429
int numentries = scandir(tempdir, &direntries, notdotentries,
2430
alphasort);
2431
if (numentries > 0){
2432
for(int i = 0; i < numentries; i++){
2433
direntry = direntries[i];
2434
char *fullname = NULL;
2435
ret = asprintf(&fullname, "%s/%s", tempdir,
2436
direntry->d_name);
2437
if(ret < 0){
2438
perror_plus("asprintf");
2439
continue;
2440
}
2441
ret = remove(fullname);
2442
if(ret == -1){
2443
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2444
strerror(errno));
2445
}
2446
free(fullname);
2447
}
2448
}
2449
2450
/* need to clean even if 0 because man page doesn't specify */
2451
free(direntries);
2452
if (numentries == -1){
2453
perror_plus("scandir");
2454
}
2455
ret = rmdir(tempdir);
2456
if(ret == -1 and errno != ENOENT){
2457
perror_plus("rmdir");
2458
}
3109
if(tempdir != NULL){
3110
clean_dir_at(-1, tempdir, 0);
2459
3111
}
2460
3112
2461
3113
if(quit_now){
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0