To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/trunk
« back to all changes in this revision
Viewing changes to plugins.d/mandos-client.c
- browse files at revision 690
- compare with another revision
- download diff
- download tarball
- view history from revision 690
- Committer: Teddy Hogeborn
- Date: 2014-06-07 20:29:36 UTC
- Revision ID: teddy@recompile.se-20140607202936-crh5fxrdd804oora
Fix typo in code comment.
* debian/mandos.postinst: Fix typo in comment.
* debian/mandos.postinst: Fix typo in comment.
- files removed:
- plugin-helpers
- files modified:
- DBUS-API
added
removed
plugins.d/mandos-client.c
9
9
* "browse_callback", and parts of "main".
10
10
*
11
11
* Everything else is
12
* Copyright © 2008-2015 Teddy Hogeborn
13
* Copyright © 2008-2015 Björn Påhlsson
12
* Copyright © 2008-2014 Teddy Hogeborn
13
* Copyright © 2008-2014 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 /* not _LARGEFILE_SOURCE */
35
#endif
36
36
#ifndef _FILE_OFFSET_BITS
37
37
#define _FILE_OFFSET_BITS 64
38
#endif /* not _FILE_OFFSET_BITS */
38
#endif
39
39
40
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
41
42
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror() */
43
stdout, ferror(), remove() */
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(),
57
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
58
inet_pton(), connect(),
59
59
getnameinfo() */
60
#include <fcntl.h> /* open(), unlinkat() */
60
#include <fcntl.h> /* open() */
61
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
62
*/
63
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
73
73
*/
74
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit(),
77
unlinkat() */
76
setgid(), pause(), _exit() */
78
77
#include <arpa/inet.h> /* inet_pton(), htons() */
79
78
#include <iso646.h> /* not, or, and */
80
79
#include <argp.h> /* struct argp_option, error_t, struct
142
141
static const char sys_class_net[] = "/sys/class/net";
143
142
char *connect_to = NULL;
144
143
const char *hookdir = HOOKDIR;
145
int hookdir_fd = -1;
146
144
uid_t uid = 65534;
147
145
gid_t gid = 65534;
148
146
234
232
.af = af };
235
233
if(new_server->ip == NULL){
236
234
perror_plus("strdup");
237
free(new_server);
238
235
return false;
239
236
}
240
237
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
241
238
if(ret == -1){
242
239
perror_plus("clock_gettime");
243
#ifdef __GNUC__
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
246
#endif
247
free((char *)(new_server->ip));
248
#ifdef __GNUC__
249
#pragma GCC diagnostic pop
250
#endif
251
free(new_server);
252
240
return false;
253
241
}
254
242
/* Special case of first server */
493
481
return plaintext_length;
494
482
}
495
483
496
__attribute__((warn_unused_result, const))
497
static const char *safe_string(const char *str){
498
if(str == NULL)
499
return "(unknown)";
500
return str;
501
}
502
503
484
__attribute__((warn_unused_result))
504
485
static const char *safer_gnutls_strerror(int value){
505
486
const char *ret = gnutls_strerror(value);
506
return safe_string(ret);
487
if(ret == NULL)
488
ret = "(unknown)";
489
return ret;
507
490
}
508
491
509
492
/* GnuTLS log function callback */
516
499
__attribute__((nonnull, warn_unused_result))
517
500
static int init_gnutls_global(const char *pubkeyfilename,
518
501
const char *seckeyfilename,
519
const char *dhparamsfilename,
520
502
mandos_context *mc){
521
503
int ret;
522
unsigned int uret;
523
504
524
505
if(debug){
525
506
fprintf_plus(stderr, "Initializing GnuTLS\n");
576
557
safer_gnutls_strerror(ret));
577
558
goto globalfail;
578
559
}
579
/* If a Diffie-Hellman parameters file was given, try to use it */
580
if(dhparamsfilename != NULL){
581
gnutls_datum_t params = { .data = NULL, .size = 0 };
582
do {
583
int dhpfile = open(dhparamsfilename, O_RDONLY);
584
if(dhpfile == -1){
585
perror_plus("open");
586
dhparamsfilename = NULL;
587
break;
588
}
589
size_t params_capacity = 0;
590
while(true){
591
params_capacity = incbuffer((char **)¶ms.data,
592
(size_t)params.size,
593
(size_t)params_capacity);
594
if(params_capacity == 0){
595
perror_plus("incbuffer");
596
free(params.data);
597
params.data = NULL;
598
dhparamsfilename = NULL;
599
break;
600
}
601
ssize_t bytes_read = read(dhpfile,
602
params.data + params.size,
603
BUFFER_SIZE);
604
/* EOF */
605
if(bytes_read == 0){
606
break;
607
}
608
/* check bytes_read for failure */
609
if(bytes_read < 0){
610
perror_plus("read");
611
free(params.data);
612
params.data = NULL;
613
dhparamsfilename = NULL;
614
break;
615
}
616
params.size += (unsigned int)bytes_read;
617
}
618
if(params.data == NULL){
619
dhparamsfilename = NULL;
620
}
621
if(dhparamsfilename == NULL){
622
break;
623
}
624
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
625
GNUTLS_X509_FMT_PEM);
626
if(ret != GNUTLS_E_SUCCESS){
627
fprintf_plus(stderr, "Failed to parse DH parameters in file"
628
" \"%s\": %s\n", dhparamsfilename,
629
safer_gnutls_strerror(ret));
630
dhparamsfilename = NULL;
631
}
632
} while(false);
633
}
634
if(dhparamsfilename == NULL){
635
if(mc->dh_bits == 0){
636
/* Find out the optimal number of DH bits */
637
/* Try to read the private key file */
638
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
639
do {
640
int secfile = open(seckeyfilename, O_RDONLY);
641
if(secfile == -1){
642
perror_plus("open");
643
break;
644
}
645
size_t buffer_capacity = 0;
646
while(true){
647
buffer_capacity = incbuffer((char **)&buffer.data,
648
(size_t)buffer.size,
649
(size_t)buffer_capacity);
650
if(buffer_capacity == 0){
651
perror_plus("incbuffer");
652
free(buffer.data);
653
buffer.data = NULL;
654
break;
655
}
656
ssize_t bytes_read = read(secfile,
657
buffer.data + buffer.size,
658
BUFFER_SIZE);
659
/* EOF */
660
if(bytes_read == 0){
661
break;
662
}
663
/* check bytes_read for failure */
664
if(bytes_read < 0){
665
perror_plus("read");
666
free(buffer.data);
667
buffer.data = NULL;
668
break;
669
}
670
buffer.size += (unsigned int)bytes_read;
671
}
672
close(secfile);
673
} while(false);
674
/* If successful, use buffer to parse private key */
675
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
676
if(buffer.data != NULL){
677
{
678
gnutls_openpgp_privkey_t privkey = NULL;
679
ret = gnutls_openpgp_privkey_init(&privkey);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error initializing OpenPGP key"
682
" structure: %s",
683
safer_gnutls_strerror(ret));
684
free(buffer.data);
685
buffer.data = NULL;
686
} else {
687
ret = gnutls_openpgp_privkey_import
688
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
689
if(ret != GNUTLS_E_SUCCESS){
690
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
691
safer_gnutls_strerror(ret));
692
privkey = NULL;
693
}
694
free(buffer.data);
695
buffer.data = NULL;
696
if(privkey != NULL){
697
/* Use private key to suggest an appropriate
698
sec_param */
699
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
700
gnutls_openpgp_privkey_deinit(privkey);
701
if(debug){
702
fprintf_plus(stderr, "This OpenPGP key implies using"
703
" a GnuTLS security parameter \"%s\".\n",
704
safe_string(gnutls_sec_param_get_name
705
(sec_param)));
706
}
707
}
708
}
709
}
710
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
711
/* Err on the side of caution */
712
sec_param = GNUTLS_SEC_PARAM_ULTRA;
713
if(debug){
714
fprintf_plus(stderr, "Falling back to security parameter"
715
" \"%s\"\n",
716
safe_string(gnutls_sec_param_get_name
717
(sec_param)));
718
}
719
}
720
}
721
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
722
if(uret != 0){
723
mc->dh_bits = uret;
724
if(debug){
725
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
726
" implies %u DH bits; using that.\n",
727
safe_string(gnutls_sec_param_get_name
728
(sec_param)),
729
mc->dh_bits);
730
}
731
} else {
732
fprintf_plus(stderr, "Failed to get implied number of DH"
733
" bits for security parameter \"%s\"): %s\n",
734
safe_string(gnutls_sec_param_get_name
735
(sec_param)),
736
safer_gnutls_strerror(ret));
737
goto globalfail;
738
}
739
} else if(debug){
740
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
741
mc->dh_bits);
742
}
743
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
744
if(ret != GNUTLS_E_SUCCESS){
745
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
746
" bits): %s\n", mc->dh_bits,
747
safer_gnutls_strerror(ret));
748
goto globalfail;
749
}
750
}
560
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
561
if(ret != GNUTLS_E_SUCCESS){
562
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
563
safer_gnutls_strerror(ret));
564
goto globalfail;
565
}
566
751
567
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
752
568
753
569
return 0;
813
629
/* ignore client certificate if any. */
814
630
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
815
631
632
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
633
816
634
return 0;
817
635
}
818
636
820
638
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
821
639
__attribute__((unused)) const char *txt){}
822
640
823
/* Set effective uid to 0, return errno */
824
__attribute__((warn_unused_result))
825
error_t raise_privileges(void){
826
error_t old_errno = errno;
827
error_t ret_errno = 0;
828
if(seteuid(0) == -1){
829
ret_errno = errno;
830
}
831
errno = old_errno;
832
return ret_errno;
833
}
834
835
/* Set effective and real user ID to 0. Return errno. */
836
__attribute__((warn_unused_result))
837
error_t raise_privileges_permanently(void){
838
error_t old_errno = errno;
839
error_t ret_errno = raise_privileges();
840
if(ret_errno != 0){
841
errno = old_errno;
842
return ret_errno;
843
}
844
if(setuid(0) == -1){
845
ret_errno = errno;
846
}
847
errno = old_errno;
848
return ret_errno;
849
}
850
851
/* Set effective user ID to unprivileged saved user ID */
852
__attribute__((warn_unused_result))
853
error_t lower_privileges(void){
854
error_t old_errno = errno;
855
error_t ret_errno = 0;
856
if(seteuid(uid) == -1){
857
ret_errno = errno;
858
}
859
errno = old_errno;
860
return ret_errno;
861
}
862
863
/* Lower privileges permanently */
864
__attribute__((warn_unused_result))
865
error_t lower_privileges_permanently(void){
866
error_t old_errno = errno;
867
error_t ret_errno = 0;
868
if(setuid(uid) == -1){
869
ret_errno = errno;
870
}
871
errno = old_errno;
872
return ret_errno;
873
}
874
875
/* Helper function to add_local_route() and delete_local_route() */
876
__attribute__((nonnull, warn_unused_result))
877
static bool add_delete_local_route(const bool add,
878
const char *address,
879
AvahiIfIndex if_index){
880
int ret;
881
char helper[] = "mandos-client-iprouteadddel";
882
char add_arg[] = "add";
883
char delete_arg[] = "delete";
884
char debug_flag[] = "--debug";
885
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
886
if(pluginhelperdir == NULL){
887
if(debug){
888
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
889
" variable not set; cannot run helper\n");
890
}
891
return false;
892
}
893
894
char interface[IF_NAMESIZE];
895
if(if_indextoname((unsigned int)if_index, interface) == NULL){
896
perror_plus("if_indextoname");
897
return false;
898
}
899
900
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
901
if(devnull == -1){
902
perror_plus("open(\"/dev/null\", O_RDONLY)");
903
return false;
904
}
905
pid_t pid = fork();
906
if(pid == 0){
907
/* Child */
908
/* Raise privileges */
909
errno = raise_privileges_permanently();
910
if(errno != 0){
911
perror_plus("Failed to raise privileges");
912
/* _exit(EX_NOPERM); */
913
} else {
914
/* Set group */
915
errno = 0;
916
ret = setgid(0);
917
if(ret == -1){
918
perror_plus("setgid");
919
_exit(EX_NOPERM);
920
}
921
/* Reset supplementary groups */
922
errno = 0;
923
ret = setgroups(0, NULL);
924
if(ret == -1){
925
perror_plus("setgroups");
926
_exit(EX_NOPERM);
927
}
928
}
929
ret = dup2(devnull, STDIN_FILENO);
930
if(ret == -1){
931
perror_plus("dup2(devnull, STDIN_FILENO)");
932
_exit(EX_OSERR);
933
}
934
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
935
if(ret == -1){
936
perror_plus("close");
937
_exit(EX_OSERR);
938
}
939
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
940
if(ret == -1){
941
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
942
_exit(EX_OSERR);
943
}
944
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
945
O_RDONLY
946
| O_DIRECTORY
947
| O_PATH
948
| O_CLOEXEC));
949
if(helperdir_fd == -1){
950
perror_plus("open");
951
_exit(EX_UNAVAILABLE);
952
}
953
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
954
helper, O_RDONLY));
955
if(helper_fd == -1){
956
perror_plus("openat");
957
_exit(EX_UNAVAILABLE);
958
}
959
TEMP_FAILURE_RETRY(close(helperdir_fd));
960
#ifdef __GNUC__
961
#pragma GCC diagnostic push
962
#pragma GCC diagnostic ignored "-Wcast-qual"
963
#endif
964
if(fexecve(helper_fd, (char *const [])
965
{ helper, add ? add_arg : delete_arg, (char *)address,
966
interface, debug ? debug_flag : NULL, NULL },
967
environ) == -1){
968
#ifdef __GNUC__
969
#pragma GCC diagnostic pop
970
#endif
971
perror_plus("fexecve");
972
_exit(EXIT_FAILURE);
973
}
974
}
975
if(pid == -1){
976
perror_plus("fork");
977
return false;
978
}
979
int status;
980
pid_t pret = -1;
981
errno = 0;
982
do {
983
pret = waitpid(pid, &status, 0);
984
if(pret == -1 and errno == EINTR and quit_now){
985
int errno_raising = 0;
986
if((errno = raise_privileges()) != 0){
987
errno_raising = errno;
988
perror_plus("Failed to raise privileges in order to"
989
" kill helper program");
990
}
991
if(kill(pid, SIGTERM) == -1){
992
perror_plus("kill");
993
}
994
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
995
perror_plus("Failed to lower privileges after killing"
996
" helper program");
997
}
998
return false;
999
}
1000
} while(pret == -1 and errno == EINTR);
1001
if(pret == -1){
1002
perror_plus("waitpid");
1003
return false;
1004
}
1005
if(WIFEXITED(status)){
1006
if(WEXITSTATUS(status) != 0){
1007
fprintf_plus(stderr, "Error: iprouteadddel exited"
1008
" with status %d\n", WEXITSTATUS(status));
1009
return false;
1010
}
1011
return true;
1012
}
1013
if(WIFSIGNALED(status)){
1014
fprintf_plus(stderr, "Error: iprouteadddel died by"
1015
" signal %d\n", WTERMSIG(status));
1016
return false;
1017
}
1018
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1019
return false;
1020
}
1021
1022
__attribute__((nonnull, warn_unused_result))
1023
static bool add_local_route(const char *address,
1024
AvahiIfIndex if_index){
1025
if(debug){
1026
fprintf_plus(stderr, "Adding route to %s\n", address);
1027
}
1028
return add_delete_local_route(true, address, if_index);
1029
}
1030
1031
__attribute__((nonnull, warn_unused_result))
1032
static bool delete_local_route(const char *address,
1033
AvahiIfIndex if_index){
1034
if(debug){
1035
fprintf_plus(stderr, "Removing route to %s\n", address);
1036
}
1037
return add_delete_local_route(false, address, if_index);
1038
}
1039
1040
641
/* Called when a Mandos server is found */
1041
642
__attribute__((nonnull, warn_unused_result))
1042
643
static int start_mandos_communication(const char *ip, in_port_t port,
1053
654
int retval = -1;
1054
655
gnutls_session_t session;
1055
656
int pf; /* Protocol family */
1056
bool route_added = false;
1057
657
1058
658
errno = 0;
1059
659
1117
717
PRIuMAX "\n", ip, (uintmax_t)port);
1118
718
}
1119
719
1120
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
720
tcp_sd = socket(pf, SOCK_STREAM, 0);
1121
721
if(tcp_sd < 0){
1122
722
int e = errno;
1123
723
perror_plus("socket");
1212
812
goto mandos_end;
1213
813
}
1214
814
1215
while(true){
1216
if(af == AF_INET6){
1217
ret = connect(tcp_sd, (struct sockaddr *)&to,
1218
sizeof(struct sockaddr_in6));
1219
} else {
1220
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1221
sizeof(struct sockaddr_in));
1222
}
1223
if(ret < 0){
1224
if(errno == ENETUNREACH
1225
and if_index != AVAHI_IF_UNSPEC
1226
and connect_to == NULL
1227
and not route_added and
1228
((af == AF_INET6 and not
1229
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1230
&to)->sin6_addr)))
1231
or (af == AF_INET and
1232
/* Not a a IPv4LL address */
1233
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1234
& 0xFFFF0000L) != 0xA9FE0000L))){
1235
/* Work around Avahi bug - Avahi does not announce link-local
1236
addresses if it has a global address, so local hosts with
1237
*only* a link-local address (e.g. Mandos clients) cannot
1238
connect to a Mandos server announced by Avahi on a server
1239
host with a global address. Work around this by retrying
1240
with an explicit route added with the server's address.
1241
1242
Avahi bug reference:
1243
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1244
https://bugs.debian.org/587961
1245
*/
1246
if(debug){
1247
fprintf_plus(stderr, "Mandos server unreachable, trying"
1248
" direct route\n");
1249
}
1250
int e = errno;
1251
route_added = add_local_route(ip, if_index);
1252
if(route_added){
1253
continue;
1254
}
1255
errno = e;
1256
}
1257
if(errno != ECONNREFUSED or debug){
1258
int e = errno;
1259
perror_plus("connect");
1260
errno = e;
1261
}
1262
goto mandos_end;
1263
}
1264
1265
if(quit_now){
1266
errno = EINTR;
1267
goto mandos_end;
1268
}
1269
break;
815
if(af == AF_INET6){
816
ret = connect(tcp_sd, (struct sockaddr *)&to,
817
sizeof(struct sockaddr_in6));
818
} else {
819
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
820
sizeof(struct sockaddr_in));
821
}
822
if(ret < 0){
823
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
824
int e = errno;
825
perror_plus("connect");
826
errno = e;
827
}
828
goto mandos_end;
829
}
830
831
if(quit_now){
832
errno = EINTR;
833
goto mandos_end;
1270
834
}
1271
835
1272
836
const char *out = mandos_protocol_version;
1455
1019
1456
1020
mandos_end:
1457
1021
{
1458
if(route_added){
1459
if(not delete_local_route(ip, if_index)){
1460
fprintf_plus(stderr, "Failed to delete local route to %s on"
1461
" interface %d", ip, if_index);
1462
}
1463
}
1464
1022
int e = errno;
1465
1023
free(decrypted_buffer);
1466
1024
free(buffer);
1506
1064
timed out */
1507
1065
1508
1066
if(quit_now){
1509
avahi_s_service_resolver_free(r);
1510
1067
return;
1511
1068
}
1512
1069
1788
1345
return 0;
1789
1346
}
1790
1347
1791
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1348
char *fullname = NULL;
1349
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1350
if(ret < 0){
1351
perror_plus("asprintf");
1352
return 0;
1353
}
1354
1355
ret = stat(fullname, &st);
1792
1356
if(ret == -1){
1793
1357
if(debug){
1794
1358
perror_plus("Could not stat hook");
1795
1359
}
1796
1360
return 0;
1797
1361
}
1362
free(fullname);
1798
1363
if(not (S_ISREG(st.st_mode))){
1799
1364
/* Not a regular file */
1800
1365
if(debug){
1892
1457
}
1893
1458
}
1894
1459
1460
/* Set effective uid to 0, return errno */
1461
__attribute__((warn_unused_result))
1462
error_t raise_privileges(void){
1463
error_t old_errno = errno;
1464
error_t ret_errno = 0;
1465
if(seteuid(0) == -1){
1466
ret_errno = errno;
1467
perror_plus("seteuid");
1468
}
1469
errno = old_errno;
1470
return ret_errno;
1471
}
1472
1473
/* Set effective and real user ID to 0. Return errno. */
1474
__attribute__((warn_unused_result))
1475
error_t raise_privileges_permanently(void){
1476
error_t old_errno = errno;
1477
error_t ret_errno = raise_privileges();
1478
if(ret_errno != 0){
1479
errno = old_errno;
1480
return ret_errno;
1481
}
1482
if(setuid(0) == -1){
1483
ret_errno = errno;
1484
perror_plus("seteuid");
1485
}
1486
errno = old_errno;
1487
return ret_errno;
1488
}
1489
1490
/* Set effective user ID to unprivileged saved user ID */
1491
__attribute__((warn_unused_result))
1492
error_t lower_privileges(void){
1493
error_t old_errno = errno;
1494
error_t ret_errno = 0;
1495
if(seteuid(uid) == -1){
1496
ret_errno = errno;
1497
perror_plus("seteuid");
1498
}
1499
errno = old_errno;
1500
return ret_errno;
1501
}
1502
1503
/* Lower privileges permanently */
1504
__attribute__((warn_unused_result))
1505
error_t lower_privileges_permanently(void){
1506
error_t old_errno = errno;
1507
error_t ret_errno = 0;
1508
if(setuid(uid) == -1){
1509
ret_errno = errno;
1510
perror_plus("setuid");
1511
}
1512
errno = old_errno;
1513
return ret_errno;
1514
}
1515
1895
1516
__attribute__((nonnull))
1896
1517
void run_network_hooks(const char *mode, const char *interface,
1897
1518
const float delay){
1898
struct dirent **direntries = NULL;
1899
if(hookdir_fd == -1){
1900
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1901
| O_CLOEXEC);
1902
if(hookdir_fd == -1){
1903
if(errno == ENOENT){
1904
if(debug){
1905
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1906
" found\n", hookdir);
1907
}
1908
} else {
1909
perror_plus("open");
1910
}
1911
return;
1912
}
1913
}
1914
#ifdef __GLIBC__
1915
#if __GLIBC_PREREQ(2, 15)
1916
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1917
runnable_hook, alphasort);
1918
#else /* not __GLIBC_PREREQ(2, 15) */
1919
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1920
alphasort);
1921
#endif /* not __GLIBC_PREREQ(2, 15) */
1922
#else /* not __GLIBC__ */
1923
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1924
alphasort);
1925
#endif /* not __GLIBC__ */
1519
struct dirent **direntries;
1520
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1521
alphasort);
1926
1522
if(numhooks == -1){
1927
perror_plus("scandir");
1928
return;
1929
}
1930
struct dirent *direntry;
1931
int ret;
1932
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1933
if(devnull == -1){
1934
perror_plus("open(\"/dev/null\", O_RDONLY)");
1935
return;
1936
}
1937
for(int i = 0; i < numhooks; i++){
1938
direntry = direntries[i];
1939
if(debug){
1940
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1941
direntry->d_name);
1523
if(errno == ENOENT){
1524
if(debug){
1525
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1526
" found\n", hookdir);
1527
}
1528
} else {
1529
perror_plus("scandir");
1942
1530
}
1943
pid_t hook_pid = fork();
1944
if(hook_pid == 0){
1945
/* Child */
1946
/* Raise privileges */
1947
errno = raise_privileges_permanently();
1948
if(errno != 0){
1949
perror_plus("Failed to raise privileges");
1950
_exit(EX_NOPERM);
1951
}
1952
/* Set group */
1953
errno = 0;
1954
ret = setgid(0);
1955
if(ret == -1){
1956
perror_plus("setgid");
1957
_exit(EX_NOPERM);
1958
}
1959
/* Reset supplementary groups */
1960
errno = 0;
1961
ret = setgroups(0, NULL);
1962
if(ret == -1){
1963
perror_plus("setgroups");
1964
_exit(EX_NOPERM);
1965
}
1966
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1967
if(ret == -1){
1968
perror_plus("setenv");
1969
_exit(EX_OSERR);
1970
}
1971
ret = setenv("DEVICE", interface, 1);
1972
if(ret == -1){
1973
perror_plus("setenv");
1974
_exit(EX_OSERR);
1975
}
1976
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1977
if(ret == -1){
1978
perror_plus("setenv");
1979
_exit(EX_OSERR);
1980
}
1981
ret = setenv("MODE", mode, 1);
1982
if(ret == -1){
1983
perror_plus("setenv");
1984
_exit(EX_OSERR);
1985
}
1986
char *delaystring;
1987
ret = asprintf(&delaystring, "%f", (double)delay);
1988
if(ret == -1){
1531
} else {
1532
struct dirent *direntry;
1533
int ret;
1534
int devnull = open("/dev/null", O_RDONLY);
1535
for(int i = 0; i < numhooks; i++){
1536
direntry = direntries[i];
1537
char *fullname = NULL;
1538
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1539
if(ret < 0){
1989
1540
perror_plus("asprintf");
1990
_exit(EX_OSERR);
1991
}
1992
ret = setenv("DELAY", delaystring, 1);
1993
if(ret == -1){
1541
continue;
1542
}
1543
if(debug){
1544
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1545
direntry->d_name);
1546
}
1547
pid_t hook_pid = fork();
1548
if(hook_pid == 0){
1549
/* Child */
1550
/* Raise privileges */
1551
if(raise_privileges_permanently() != 0){
1552
perror_plus("Failed to raise privileges");
1553
_exit(EX_NOPERM);
1554
}
1555
/* Set group */
1556
errno = 0;
1557
ret = setgid(0);
1558
if(ret == -1){
1559
perror_plus("setgid");
1560
_exit(EX_NOPERM);
1561
}
1562
/* Reset supplementary groups */
1563
errno = 0;
1564
ret = setgroups(0, NULL);
1565
if(ret == -1){
1566
perror_plus("setgroups");
1567
_exit(EX_NOPERM);
1568
}
1569
ret = dup2(devnull, STDIN_FILENO);
1570
if(ret == -1){
1571
perror_plus("dup2(devnull, STDIN_FILENO)");
1572
_exit(EX_OSERR);
1573
}
1574
ret = close(devnull);
1575
if(ret == -1){
1576
perror_plus("close");
1577
_exit(EX_OSERR);
1578
}
1579
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1580
if(ret == -1){
1581
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1582
_exit(EX_OSERR);
1583
}
1584
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1585
if(ret == -1){
1586
perror_plus("setenv");
1587
_exit(EX_OSERR);
1588
}
1589
ret = setenv("DEVICE", interface, 1);
1590
if(ret == -1){
1591
perror_plus("setenv");
1592
_exit(EX_OSERR);
1593
}
1594
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1595
if(ret == -1){
1596
perror_plus("setenv");
1597
_exit(EX_OSERR);
1598
}
1599
ret = setenv("MODE", mode, 1);
1600
if(ret == -1){
1601
perror_plus("setenv");
1602
_exit(EX_OSERR);
1603
}
1604
char *delaystring;
1605
ret = asprintf(&delaystring, "%f", (double)delay);
1606
if(ret == -1){
1607
perror_plus("asprintf");
1608
_exit(EX_OSERR);
1609
}
1610
ret = setenv("DELAY", delaystring, 1);
1611
if(ret == -1){
1612
free(delaystring);
1613
perror_plus("setenv");
1614
_exit(EX_OSERR);
1615
}
1994
1616
free(delaystring);
1995
perror_plus("setenv");
1996
_exit(EX_OSERR);
1997
}
1998
free(delaystring);
1999
if(connect_to != NULL){
2000
ret = setenv("CONNECT", connect_to, 1);
2001
if(ret == -1){
2002
perror_plus("setenv");
2003
_exit(EX_OSERR);
2004
}
2005
}
2006
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2007
direntry->d_name,
2008
O_RDONLY));
2009
if(hook_fd == -1){
2010
perror_plus("openat");
2011
_exit(EXIT_FAILURE);
2012
}
2013
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2014
perror_plus("close");
2015
_exit(EXIT_FAILURE);
2016
}
2017
ret = dup2(devnull, STDIN_FILENO);
2018
if(ret == -1){
2019
perror_plus("dup2(devnull, STDIN_FILENO)");
2020
_exit(EX_OSERR);
2021
}
2022
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
2023
if(ret == -1){
2024
perror_plus("close");
2025
_exit(EX_OSERR);
2026
}
2027
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2028
if(ret == -1){
2029
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2030
_exit(EX_OSERR);
2031
}
2032
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2033
environ) == -1){
2034
perror_plus("fexecve");
2035
_exit(EXIT_FAILURE);
2036
}
2037
} else {
2038
if(hook_pid == -1){
2039
perror_plus("fork");
2040
free(direntry);
2041
continue;
2042
}
2043
int status;
2044
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2045
perror_plus("waitpid");
2046
free(direntry);
2047
continue;
2048
}
2049
if(WIFEXITED(status)){
2050
if(WEXITSTATUS(status) != 0){
2051
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2052
" with status %d\n", direntry->d_name,
2053
WEXITSTATUS(status));
2054
free(direntry);
2055
continue;
2056
}
2057
} else if(WIFSIGNALED(status)){
2058
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2059
" signal %d\n", direntry->d_name,
2060
WTERMSIG(status));
2061
free(direntry);
2062
continue;
1617
if(connect_to != NULL){
1618
ret = setenv("CONNECT", connect_to, 1);
1619
if(ret == -1){
1620
perror_plus("setenv");
1621
_exit(EX_OSERR);
1622
}
1623
}
1624
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1625
perror_plus("execl");
1626
_exit(EXIT_FAILURE);
1627
}
2063
1628
} else {
2064
fprintf_plus(stderr, "Warning: network hook \"%s\""
2065
" crashed\n", direntry->d_name);
2066
free(direntry);
2067
continue;
2068
}
2069
}
2070
if(debug){
2071
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2072
direntry->d_name);
2073
}
2074
free(direntry);
2075
}
2076
free(direntries);
2077
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2078
perror_plus("close");
2079
} else {
2080
hookdir_fd = -1;
2081
}
2082
close(devnull);
1629
int status;
1630
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1631
perror_plus("waitpid");
1632
free(fullname);
1633
continue;
1634
}
1635
if(WIFEXITED(status)){
1636
if(WEXITSTATUS(status) != 0){
1637
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1638
" with status %d\n", direntry->d_name,
1639
WEXITSTATUS(status));
1640
free(fullname);
1641
continue;
1642
}
1643
} else if(WIFSIGNALED(status)){
1644
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1645
" signal %d\n", direntry->d_name,
1646
WTERMSIG(status));
1647
free(fullname);
1648
continue;
1649
} else {
1650
fprintf_plus(stderr, "Warning: network hook \"%s\""
1651
" crashed\n", direntry->d_name);
1652
free(fullname);
1653
continue;
1654
}
1655
}
1656
free(fullname);
1657
if(debug){
1658
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1659
direntry->d_name);
1660
}
1661
}
1662
close(devnull);
1663
}
2083
1664
}
2084
1665
2085
1666
__attribute__((nonnull, warn_unused_result))
2136
1717
/* Raise privileges */
2137
1718
ret_errno = raise_privileges();
2138
1719
if(ret_errno != 0){
2139
errno = ret_errno;
2140
1720
perror_plus("Failed to raise privileges");
2141
1721
}
2142
1722
2246
1826
/* Raise privileges */
2247
1827
ret_errno = raise_privileges();
2248
1828
if(ret_errno != 0){
2249
errno = ret_errno;
2250
1829
perror_plus("Failed to raise privileges");
2251
1830
}
2252
1831
2285
1864
}
2286
1865
2287
1866
int main(int argc, char *argv[]){
2288
mandos_context mc = { .server = NULL, .dh_bits = 0,
1867
mandos_context mc = { .server = NULL, .dh_bits = 1024,
2289
1868
.priority = "SECURE256:!CTYPE-X.509:"
2290
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
1869
"+CTYPE-OPENPGP", .current_server = NULL,
2291
1870
.interfaces = NULL, .interfaces_size = 0 };
2292
1871
AvahiSServiceBrowser *sb = NULL;
2293
1872
error_t ret_errno;
2303
1882
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2304
1883
const char *seckey = PATHDIR "/" SECKEY;
2305
1884
const char *pubkey = PATHDIR "/" PUBKEY;
2306
const char *dh_params_file = NULL;
2307
1885
char *interfaces_hooks = NULL;
2308
1886
2309
1887
bool gnutls_initialized = false;
2362
1940
.doc = "Bit length of the prime number used in the"
2363
1941
" Diffie-Hellman key exchange",
2364
1942
.group = 2 },
2365
{ .name = "dh-params", .key = 134,
2366
.arg = "FILE",
2367
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2368
" for the Diffie-Hellman key exchange",
2369
.group = 2 },
2370
1943
{ .name = "priority", .key = 130,
2371
1944
.arg = "STRING",
2372
1945
.doc = "GnuTLS priority string for the TLS handshake",
2427
2000
}
2428
2001
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2429
2002
break;
2430
case 134: /* --dh-params */
2431
dh_params_file = arg;
2432
break;
2433
2003
case 130: /* --priority */
2434
2004
mc.priority = arg;
2435
2005
break;
2491
2061
goto end;
2492
2062
}
2493
2063
}
2494
2064
2495
2065
{
2496
2066
/* Work around Debian bug #633582:
2497
2067
<http://bugs.debian.org/633582> */
2524
2094
TEMP_FAILURE_RETRY(close(seckey_fd));
2525
2095
}
2526
2096
}
2527
2097
2528
2098
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2529
2099
int pubkey_fd = open(pubkey, O_RDONLY);
2530
2100
if(pubkey_fd == -1){
2545
2115
TEMP_FAILURE_RETRY(close(pubkey_fd));
2546
2116
}
2547
2117
}
2548
2549
if(strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2550
int dhparams_fd = open(dh_params_file, O_RDONLY);
2551
if(dhparams_fd == -1){
2552
perror_plus("open");
2553
} else {
2554
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2555
if(ret == -1){
2556
perror_plus("fstat");
2557
} else {
2558
if(S_ISREG(st.st_mode)
2559
and st.st_uid == 0 and st.st_gid == 0){
2560
ret = fchown(dhparams_fd, uid, gid);
2561
if(ret == -1){
2562
perror_plus("fchown");
2563
}
2564
}
2565
}
2566
TEMP_FAILURE_RETRY(close(dhparams_fd));
2567
}
2568
}
2569
2118
2570
2119
/* Lower privileges */
2571
2120
ret_errno = lower_privileges();
2572
2121
if(ret_errno != 0){
2689
2238
2690
2239
/* If no interfaces were specified, make a list */
2691
2240
if(mc.interfaces == NULL){
2692
struct dirent **direntries = NULL;
2241
struct dirent **direntries;
2693
2242
/* Look for any good interfaces */
2694
2243
ret = scandir(sys_class_net, &direntries, good_interface,
2695
2244
alphasort);
2701
2250
if(ret_errno != 0){
2702
2251
errno = ret_errno;
2703
2252
perror_plus("argz_add");
2704
free(direntries[i]);
2705
2253
continue;
2706
2254
}
2707
2255
if(debug){
2708
2256
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2709
2257
direntries[i]->d_name);
2710
2258
}
2711
free(direntries[i]);
2712
2259
}
2713
2260
free(direntries);
2714
2261
} else {
2715
if(ret == 0){
2716
free(direntries);
2717
}
2262
free(direntries);
2718
2263
fprintf_plus(stderr, "Could not find a network interface\n");
2719
2264
exitcode = EXIT_FAILURE;
2720
2265
goto end;
2775
2320
goto end;
2776
2321
}
2777
2322
2778
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2323
ret = init_gnutls_global(pubkey, seckey, &mc);
2779
2324
if(ret == -1){
2780
2325
fprintf_plus(stderr, "init_gnutls_global failed\n");
2781
2326
exitcode = EX_UNAVAILABLE;
2984
2529
mc.current_server->prev->next = NULL;
2985
2530
while(mc.current_server != NULL){
2986
2531
server *next = mc.current_server->next;
2987
#ifdef __GNUC__
2988
#pragma GCC diagnostic push
2989
#pragma GCC diagnostic ignored "-Wcast-qual"
2990
#endif
2991
free((char *)(mc.current_server->ip));
2992
#ifdef __GNUC__
2993
#pragma GCC diagnostic pop
2994
#endif
2995
2532
free(mc.current_server);
2996
2533
mc.current_server = next;
2997
2534
}
3001
2538
{
3002
2539
ret_errno = raise_privileges();
3003
2540
if(ret_errno != 0){
3004
errno = ret_errno;
3005
2541
perror_plus("Failed to raise privileges");
3006
2542
} else {
3007
2543
3030
2566
3031
2567
ret_errno = lower_privileges_permanently();
3032
2568
if(ret_errno != 0){
3033
errno = ret_errno;
3034
2569
perror_plus("Failed to lower privileges permanently");
3035
2570
}
3036
2571
}
3041
2576
/* Removes the GPGME temp directory and all files inside */
3042
2577
if(tempdir != NULL){
3043
2578
struct dirent **direntries = NULL;
3044
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3045
| O_NOFOLLOW
3046
| O_DIRECTORY
3047
| O_PATH));
3048
if(tempdir_fd == -1){
3049
perror_plus("open");
3050
} else {
3051
#ifdef __GLIBC__
3052
#if __GLIBC_PREREQ(2, 15)
3053
int numentries = scandirat(tempdir_fd, ".", &direntries,
3054
notdotentries, alphasort);
3055
#else /* not __GLIBC_PREREQ(2, 15) */
3056
int numentries = scandir(tempdir, &direntries, notdotentries,
3057
alphasort);
3058
#endif /* not __GLIBC_PREREQ(2, 15) */
3059
#else /* not __GLIBC__ */
3060
int numentries = scandir(tempdir, &direntries, notdotentries,
3061
alphasort);
3062
#endif /* not __GLIBC__ */
3063
if(numentries >= 0){
3064
for(int i = 0; i < numentries; i++){
3065
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3066
if(ret == -1){
3067
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3068
" \"%s\", 0): %s\n", tempdir,
3069
direntries[i]->d_name, strerror(errno));
3070
}
3071
free(direntries[i]);
3072
}
3073
3074
/* need to clean even if 0 because man page doesn't specify */
3075
free(direntries);
3076
if(numentries == -1){
3077
perror_plus("scandir");
3078
}
3079
ret = rmdir(tempdir);
3080
if(ret == -1 and errno != ENOENT){
3081
perror_plus("rmdir");
3082
}
2579
struct dirent *direntry = NULL;
2580
int numentries = scandir(tempdir, &direntries, notdotentries,
2581
alphasort);
2582
if(numentries > 0){
2583
for(int i = 0; i < numentries; i++){
2584
direntry = direntries[i];
2585
char *fullname = NULL;
2586
ret = asprintf(&fullname, "%s/%s", tempdir,
2587
direntry->d_name);
2588
if(ret < 0){
2589
perror_plus("asprintf");
2590
continue;
2591
}
2592
ret = remove(fullname);
2593
if(ret == -1){
2594
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2595
strerror(errno));
2596
}
2597
free(fullname);
3083
2598
}
3084
TEMP_FAILURE_RETRY(close(tempdir_fd));
2599
}
2600
2601
/* need to clean even if 0 because man page doesn't specify */
2602
free(direntries);
2603
if(numentries == -1){
2604
perror_plus("scandir");
2605
}
2606
ret = rmdir(tempdir);
2607
if(ret == -1 and errno != ENOENT){
2608
perror_plus("rmdir");
3085
2609
}
3086
2610
}
3087
2611
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0