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- Committer: Teddy Hogeborn
- Date: 2015-05-23 12:07:07 UTC
- Revision ID: teddy@recompile.se-20150523120707-t5fq0brh2kxkvw8g
mandos: Some more minor changes to prepare for Python 3.
added
removed
plugins.d/mandos-client.c
9
9
* "browse_callback", and parts of "main".
10
10
*
11
11
* Everything else is
12
* Copyright © 2008-2016 Teddy Hogeborn
13
* Copyright © 2008-2016 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
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> /* strcmp(), strlen(), strerror(),
50
asprintf(), strncpy() */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
51
#include <sys/ioctl.h> /* ioctl */
52
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
53
sockaddr_in6, PF_INET6,
57
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
58
inet_pton(), connect(),
59
59
getnameinfo() */
60
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
#include <fcntl.h> /* open(), unlinkat() */
61
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
62
*/
63
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
64
strtoimax() */
65
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
66
EAI_SYSTEM, ENETUNREACH,
67
EHOSTUNREACH, ECONNREFUSED, EPROTO,
68
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
69
ENOTEMPTY,
65
#include <errno.h> /* perror(), errno,
70
66
program_invocation_short_name */
71
67
#include <time.h> /* nanosleep(), time(), sleep() */
72
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
309
305
return false;
310
306
}
311
307
312
ret = close(fd);
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
313
309
if(ret == -1){
314
310
perror_plus("close");
315
311
}
517
513
fprintf_plus(stderr, "GnuTLS: %s", string);
518
514
}
519
515
520
__attribute__((nonnull(1, 2, 4), warn_unused_result))
516
__attribute__((nonnull, warn_unused_result))
521
517
static int init_gnutls_global(const char *pubkeyfilename,
522
518
const char *seckeyfilename,
523
const char *dhparamsfilename,
524
519
mandos_context *mc){
525
520
int ret;
526
521
unsigned int uret;
529
524
fprintf_plus(stderr, "Initializing GnuTLS\n");
530
525
}
531
526
527
ret = gnutls_global_init();
528
if(ret != GNUTLS_E_SUCCESS){
529
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
530
safer_gnutls_strerror(ret));
531
return -1;
532
}
533
532
534
if(debug){
533
535
/* "Use a log level over 10 to enable all debugging options."
534
536
* - GnuTLS manual
542
544
if(ret != GNUTLS_E_SUCCESS){
543
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
544
546
safer_gnutls_strerror(ret));
547
gnutls_global_deinit();
545
548
return -1;
546
549
}
547
550
572
575
safer_gnutls_strerror(ret));
573
576
goto globalfail;
574
577
}
575
/* If a Diffie-Hellman parameters file was given, try to use it */
576
if(dhparamsfilename != NULL){
577
gnutls_datum_t params = { .data = NULL, .size = 0 };
578
do {
579
int dhpfile = open(dhparamsfilename, O_RDONLY);
580
if(dhpfile == -1){
581
perror_plus("open");
582
dhparamsfilename = NULL;
583
break;
584
}
585
size_t params_capacity = 0;
578
if(mc->dh_bits == 0){
579
/* Find out the optimal number of DH bits */
580
/* Try to read the private key file */
581
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
582
{
583
int secfile = open(seckeyfilename, O_RDONLY);
584
size_t buffer_capacity = 0;
586
585
while(true){
587
params_capacity = incbuffer((char **)¶ms.data,
588
(size_t)params.size,
589
(size_t)params_capacity);
590
if(params_capacity == 0){
586
buffer_capacity = incbuffer((char **)&buffer.data,
587
(size_t)buffer.size,
588
(size_t)buffer_capacity);
589
if(buffer_capacity == 0){
591
590
perror_plus("incbuffer");
592
free(params.data);
593
params.data = NULL;
594
dhparamsfilename = NULL;
591
free(buffer.data);
592
buffer.data = NULL;
595
593
break;
596
594
}
597
ssize_t bytes_read = read(dhpfile,
598
params.data + params.size,
595
ssize_t bytes_read = read(secfile, buffer.data + buffer.size,
599
596
BUFFER_SIZE);
600
597
/* EOF */
601
598
if(bytes_read == 0){
604
601
/* check bytes_read for failure */
605
602
if(bytes_read < 0){
606
603
perror_plus("read");
607
free(params.data);
608
params.data = NULL;
609
dhparamsfilename = NULL;
610
break;
611
}
612
params.size += (unsigned int)bytes_read;
613
}
614
if(params.data == NULL){
615
dhparamsfilename = NULL;
616
}
617
if(dhparamsfilename == NULL){
618
break;
619
}
620
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
621
GNUTLS_X509_FMT_PEM);
622
if(ret != GNUTLS_E_SUCCESS){
623
fprintf_plus(stderr, "Failed to parse DH parameters in file"
624
" \"%s\": %s\n", dhparamsfilename,
625
safer_gnutls_strerror(ret));
626
dhparamsfilename = NULL;
627
}
628
} while(false);
629
}
630
if(dhparamsfilename == NULL){
631
if(mc->dh_bits == 0){
632
/* Find out the optimal number of DH bits */
633
/* Try to read the private key file */
634
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
635
do {
636
int secfile = open(seckeyfilename, O_RDONLY);
637
if(secfile == -1){
638
perror_plus("open");
639
break;
640
}
641
size_t buffer_capacity = 0;
642
while(true){
643
buffer_capacity = incbuffer((char **)&buffer.data,
644
(size_t)buffer.size,
645
(size_t)buffer_capacity);
646
if(buffer_capacity == 0){
647
perror_plus("incbuffer");
648
free(buffer.data);
649
buffer.data = NULL;
650
break;
651
}
652
ssize_t bytes_read = read(secfile,
653
buffer.data + buffer.size,
654
BUFFER_SIZE);
655
/* EOF */
656
if(bytes_read == 0){
657
break;
658
}
659
/* check bytes_read for failure */
660
if(bytes_read < 0){
661
perror_plus("read");
662
free(buffer.data);
663
buffer.data = NULL;
664
break;
665
}
666
buffer.size += (unsigned int)bytes_read;
667
}
668
close(secfile);
669
} while(false);
670
/* If successful, use buffer to parse private key */
671
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
672
if(buffer.data != NULL){
673
{
674
gnutls_openpgp_privkey_t privkey = NULL;
675
ret = gnutls_openpgp_privkey_init(&privkey);
604
free(buffer.data);
605
buffer.data = NULL;
606
break;
607
}
608
buffer.size += (unsigned int)bytes_read;
609
}
610
close(secfile);
611
}
612
/* If successful, use buffer to parse private key */
613
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
614
if(buffer.data != NULL){
615
{
616
gnutls_openpgp_privkey_t privkey = NULL;
617
ret = gnutls_openpgp_privkey_init(&privkey);
618
if(ret != GNUTLS_E_SUCCESS){
619
fprintf_plus(stderr, "Error initializing OpenPGP key"
620
" structure: %s", safer_gnutls_strerror(ret));
621
free(buffer.data);
622
buffer.data = NULL;
623
} else {
624
ret = gnutls_openpgp_privkey_import(privkey, &buffer,
625
GNUTLS_OPENPGP_FMT_BASE64,
626
"", 0);
676
627
if(ret != GNUTLS_E_SUCCESS){
677
fprintf_plus(stderr, "Error initializing OpenPGP key"
678
" structure: %s",
628
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
679
629
safer_gnutls_strerror(ret));
680
free(buffer.data);
681
buffer.data = NULL;
682
} else {
683
ret = gnutls_openpgp_privkey_import
684
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
685
if(ret != GNUTLS_E_SUCCESS){
686
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
687
safer_gnutls_strerror(ret));
688
privkey = NULL;
689
}
690
free(buffer.data);
691
buffer.data = NULL;
692
if(privkey != NULL){
693
/* Use private key to suggest an appropriate
694
sec_param */
695
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
696
gnutls_openpgp_privkey_deinit(privkey);
697
if(debug){
698
fprintf_plus(stderr, "This OpenPGP key implies using"
699
" a GnuTLS security parameter \"%s\".\n",
700
safe_string(gnutls_sec_param_get_name
701
(sec_param)));
702
}
703
}
630
privkey = NULL;
704
631
}
705
}
706
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
707
/* Err on the side of caution */
708
sec_param = GNUTLS_SEC_PARAM_ULTRA;
709
if(debug){
710
fprintf_plus(stderr, "Falling back to security parameter"
711
" \"%s\"\n",
712
safe_string(gnutls_sec_param_get_name
713
(sec_param)));
632
free(buffer.data);
633
buffer.data = NULL;
634
if(privkey != NULL){
635
/* Use private key to suggest an appropriate sec_param */
636
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
637
gnutls_openpgp_privkey_deinit(privkey);
638
if(debug){
639
fprintf_plus(stderr, "This OpenPGP key implies using a"
640
" GnuTLS security parameter \"%s\".\n",
641
safe_string(gnutls_sec_param_get_name
642
(sec_param)));
643
}
714
644
}
715
645
}
716
646
}
717
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
718
if(uret != 0){
719
mc->dh_bits = uret;
647
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
648
/* Err on the side of caution */
649
sec_param = GNUTLS_SEC_PARAM_ULTRA;
720
650
if(debug){
721
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
722
" implies %u DH bits; using that.\n",
651
fprintf_plus(stderr, "Falling back to security parameter"
652
" \"%s\"\n",
723
653
safe_string(gnutls_sec_param_get_name
724
(sec_param)),
725
mc->dh_bits);
654
(sec_param)));
726
655
}
727
} else {
728
fprintf_plus(stderr, "Failed to get implied number of DH"
729
" bits for security parameter \"%s\"): %s\n",
656
}
657
}
658
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
659
if(uret != 0){
660
mc->dh_bits = uret;
661
if(debug){
662
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
663
" implies %u DH bits; using that.\n",
730
664
safe_string(gnutls_sec_param_get_name
731
665
(sec_param)),
732
safer_gnutls_strerror(ret));
733
goto globalfail;
666
mc->dh_bits);
734
667
}
735
} else if(debug){
736
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
737
mc->dh_bits);
738
}
739
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
740
if(ret != GNUTLS_E_SUCCESS){
741
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
742
" bits): %s\n", mc->dh_bits,
668
} else {
669
fprintf_plus(stderr, "Failed to get implied number of DH"
670
" bits for security parameter \"%s\"): %s\n",
671
safe_string(gnutls_sec_param_get_name(sec_param)),
743
672
safer_gnutls_strerror(ret));
744
673
goto globalfail;
745
674
}
746
}
675
} else if(debug){
676
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
677
mc->dh_bits);
678
}
679
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u bits):"
682
" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));
683
goto globalfail;
684
}
685
747
686
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
748
687
749
688
return 0;
751
690
globalfail:
752
691
753
692
gnutls_certificate_free_credentials(mc->cred);
693
gnutls_global_deinit();
754
694
gnutls_dh_params_deinit(mc->dh_params);
755
695
return -1;
756
696
}
808
748
/* ignore client certificate if any. */
809
749
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
810
750
751
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
752
811
753
return 0;
812
754
}
813
755
815
757
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
816
758
__attribute__((unused)) const char *txt){}
817
759
818
/* Set effective uid to 0, return errno */
819
__attribute__((warn_unused_result))
820
int raise_privileges(void){
821
int old_errno = errno;
822
int ret = 0;
823
if(seteuid(0) == -1){
824
ret = errno;
825
}
826
errno = old_errno;
827
return ret;
828
}
829
830
/* Set effective and real user ID to 0. Return errno. */
831
__attribute__((warn_unused_result))
832
int raise_privileges_permanently(void){
833
int old_errno = errno;
834
int ret = raise_privileges();
835
if(ret != 0){
836
errno = old_errno;
837
return ret;
838
}
839
if(setuid(0) == -1){
840
ret = errno;
841
}
842
errno = old_errno;
843
return ret;
844
}
845
846
/* Set effective user ID to unprivileged saved user ID */
847
__attribute__((warn_unused_result))
848
int lower_privileges(void){
849
int old_errno = errno;
850
int ret = 0;
851
if(seteuid(uid) == -1){
852
ret = errno;
853
}
854
errno = old_errno;
855
return ret;
856
}
857
858
/* Lower privileges permanently */
859
__attribute__((warn_unused_result))
860
int lower_privileges_permanently(void){
861
int old_errno = errno;
862
int ret = 0;
863
if(setuid(uid) == -1){
864
ret = errno;
865
}
866
errno = old_errno;
867
return ret;
868
}
869
870
/* Helper function to add_local_route() and delete_local_route() */
871
__attribute__((nonnull, warn_unused_result))
872
static bool add_delete_local_route(const bool add,
873
const char *address,
874
AvahiIfIndex if_index){
875
int ret;
876
char helper[] = "mandos-client-iprouteadddel";
877
char add_arg[] = "add";
878
char delete_arg[] = "delete";
879
char debug_flag[] = "--debug";
880
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
881
if(pluginhelperdir == NULL){
882
if(debug){
883
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
884
" variable not set; cannot run helper\n");
885
}
886
return false;
887
}
888
889
char interface[IF_NAMESIZE];
890
if(if_indextoname((unsigned int)if_index, interface) == NULL){
891
perror_plus("if_indextoname");
892
return false;
893
}
894
895
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
896
if(devnull == -1){
897
perror_plus("open(\"/dev/null\", O_RDONLY)");
898
return false;
899
}
900
pid_t pid = fork();
901
if(pid == 0){
902
/* Child */
903
/* Raise privileges */
904
errno = raise_privileges_permanently();
905
if(errno != 0){
906
perror_plus("Failed to raise privileges");
907
/* _exit(EX_NOPERM); */
908
} else {
909
/* Set group */
910
errno = 0;
911
ret = setgid(0);
912
if(ret == -1){
913
perror_plus("setgid");
914
_exit(EX_NOPERM);
915
}
916
/* Reset supplementary groups */
917
errno = 0;
918
ret = setgroups(0, NULL);
919
if(ret == -1){
920
perror_plus("setgroups");
921
_exit(EX_NOPERM);
922
}
923
}
924
ret = dup2(devnull, STDIN_FILENO);
925
if(ret == -1){
926
perror_plus("dup2(devnull, STDIN_FILENO)");
927
_exit(EX_OSERR);
928
}
929
ret = close(devnull);
930
if(ret == -1){
931
perror_plus("close");
932
_exit(EX_OSERR);
933
}
934
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
935
if(ret == -1){
936
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
937
_exit(EX_OSERR);
938
}
939
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
940
O_RDONLY
941
| O_DIRECTORY
942
| O_PATH
943
| O_CLOEXEC));
944
if(helperdir_fd == -1){
945
perror_plus("open");
946
_exit(EX_UNAVAILABLE);
947
}
948
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
949
helper, O_RDONLY));
950
if(helper_fd == -1){
951
perror_plus("openat");
952
close(helperdir_fd);
953
_exit(EX_UNAVAILABLE);
954
}
955
close(helperdir_fd);
956
#ifdef __GNUC__
957
#pragma GCC diagnostic push
958
#pragma GCC diagnostic ignored "-Wcast-qual"
959
#endif
960
if(fexecve(helper_fd, (char *const [])
961
{ helper, add ? add_arg : delete_arg, (char *)address,
962
interface, debug ? debug_flag : NULL, NULL },
963
environ) == -1){
964
#ifdef __GNUC__
965
#pragma GCC diagnostic pop
966
#endif
967
perror_plus("fexecve");
968
_exit(EXIT_FAILURE);
969
}
970
}
971
if(pid == -1){
972
perror_plus("fork");
973
return false;
974
}
975
int status;
976
pid_t pret = -1;
977
errno = 0;
978
do {
979
pret = waitpid(pid, &status, 0);
980
if(pret == -1 and errno == EINTR and quit_now){
981
int errno_raising = 0;
982
if((errno = raise_privileges()) != 0){
983
errno_raising = errno;
984
perror_plus("Failed to raise privileges in order to"
985
" kill helper program");
986
}
987
if(kill(pid, SIGTERM) == -1){
988
perror_plus("kill");
989
}
990
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
991
perror_plus("Failed to lower privileges after killing"
992
" helper program");
993
}
994
return false;
995
}
996
} while(pret == -1 and errno == EINTR);
997
if(pret == -1){
998
perror_plus("waitpid");
999
return false;
1000
}
1001
if(WIFEXITED(status)){
1002
if(WEXITSTATUS(status) != 0){
1003
fprintf_plus(stderr, "Error: iprouteadddel exited"
1004
" with status %d\n", WEXITSTATUS(status));
1005
return false;
1006
}
1007
return true;
1008
}
1009
if(WIFSIGNALED(status)){
1010
fprintf_plus(stderr, "Error: iprouteadddel died by"
1011
" signal %d\n", WTERMSIG(status));
1012
return false;
1013
}
1014
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1015
return false;
1016
}
1017
1018
__attribute__((nonnull, warn_unused_result))
1019
static bool add_local_route(const char *address,
1020
AvahiIfIndex if_index){
1021
if(debug){
1022
fprintf_plus(stderr, "Adding route to %s\n", address);
1023
}
1024
return add_delete_local_route(true, address, if_index);
1025
}
1026
1027
__attribute__((nonnull, warn_unused_result))
1028
static bool delete_local_route(const char *address,
1029
AvahiIfIndex if_index){
1030
if(debug){
1031
fprintf_plus(stderr, "Removing route to %s\n", address);
1032
}
1033
return add_delete_local_route(false, address, if_index);
1034
}
1035
1036
760
/* Called when a Mandos server is found */
1037
761
__attribute__((nonnull, warn_unused_result))
1038
762
static int start_mandos_communication(const char *ip, in_port_t port,
1049
773
int retval = -1;
1050
774
gnutls_session_t session;
1051
775
int pf; /* Protocol family */
1052
bool route_added = false;
1053
776
1054
777
errno = 0;
1055
778
1113
836
PRIuMAX "\n", ip, (uintmax_t)port);
1114
837
}
1115
838
1116
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
839
tcp_sd = socket(pf, SOCK_STREAM, 0);
1117
840
if(tcp_sd < 0){
1118
841
int e = errno;
1119
842
perror_plus("socket");
1126
849
goto mandos_end;
1127
850
}
1128
851
852
memset(&to, 0, sizeof(to));
1129
853
if(af == AF_INET6){
1130
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1131
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1132
ret = inet_pton(af, ip, &to6->sin6_addr);
854
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
855
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
1133
856
} else { /* IPv4 */
1134
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1135
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to4->sin_addr);
857
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
858
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
1137
859
}
1138
860
if(ret < 0 ){
1139
861
int e = errno;
1209
931
goto mandos_end;
1210
932
}
1211
933
1212
while(true){
1213
if(af == AF_INET6){
1214
ret = connect(tcp_sd, (struct sockaddr *)&to,
1215
sizeof(struct sockaddr_in6));
1216
} else {
1217
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1218
sizeof(struct sockaddr_in));
1219
}
1220
if(ret < 0){
1221
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1222
and if_index != AVAHI_IF_UNSPEC
1223
and connect_to == NULL
1224
and not route_added and
1225
((af == AF_INET6 and not
1226
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1227
&to)->sin6_addr)))
1228
or (af == AF_INET and
1229
/* Not a a IPv4LL address */
1230
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1231
& 0xFFFF0000L) != 0xA9FE0000L))){
1232
/* Work around Avahi bug - Avahi does not announce link-local
1233
addresses if it has a global address, so local hosts with
1234
*only* a link-local address (e.g. Mandos clients) cannot
1235
connect to a Mandos server announced by Avahi on a server
1236
host with a global address. Work around this by retrying
1237
with an explicit route added with the server's address.
1238
1239
Avahi bug reference:
1240
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1241
https://bugs.debian.org/587961
1242
*/
1243
if(debug){
1244
fprintf_plus(stderr, "Mandos server unreachable, trying"
1245
" direct route\n");
1246
}
1247
int e = errno;
1248
route_added = add_local_route(ip, if_index);
1249
if(route_added){
1250
continue;
1251
}
1252
errno = e;
1253
}
1254
if(errno != ECONNREFUSED or debug){
1255
int e = errno;
1256
perror_plus("connect");
1257
errno = e;
1258
}
1259
goto mandos_end;
1260
}
1261
1262
if(quit_now){
1263
errno = EINTR;
1264
goto mandos_end;
1265
}
1266
break;
934
if(af == AF_INET6){
935
ret = connect(tcp_sd, (struct sockaddr *)&to,
936
sizeof(struct sockaddr_in6));
937
} else {
938
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
939
sizeof(struct sockaddr_in));
940
}
941
if(ret < 0){
942
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
943
int e = errno;
944
perror_plus("connect");
945
errno = e;
946
}
947
goto mandos_end;
948
}
949
950
if(quit_now){
951
errno = EINTR;
952
goto mandos_end;
1267
953
}
1268
954
1269
955
const char *out = mandos_protocol_version;
1452
1138
1453
1139
mandos_end:
1454
1140
{
1455
if(route_added){
1456
if(not delete_local_route(ip, if_index)){
1457
fprintf_plus(stderr, "Failed to delete local route to %s on"
1458
" interface %d", ip, if_index);
1459
}
1460
}
1461
1141
int e = errno;
1462
1142
free(decrypted_buffer);
1463
1143
free(buffer);
1464
1144
if(tcp_sd >= 0){
1465
ret = close(tcp_sd);
1145
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1466
1146
}
1467
1147
if(ret == -1){
1468
1148
if(e == 0){
1623
1303
__attribute__((nonnull, warn_unused_result))
1624
1304
bool get_flags(const char *ifname, struct ifreq *ifr){
1625
1305
int ret;
1626
int old_errno;
1306
error_t ret_errno;
1627
1307
1628
1308
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1629
1309
if(s < 0){
1630
old_errno = errno;
1310
ret_errno = errno;
1631
1311
perror_plus("socket");
1632
errno = old_errno;
1312
errno = ret_errno;
1633
1313
return false;
1634
1314
}
1635
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1636
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1315
strcpy(ifr->ifr_name, ifname);
1637
1316
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1638
1317
if(ret == -1){
1639
1318
if(debug){
1640
old_errno = errno;
1319
ret_errno = errno;
1641
1320
perror_plus("ioctl SIOCGIFFLAGS");
1642
errno = old_errno;
1321
errno = ret_errno;
1643
1322
}
1644
1323
return false;
1645
1324
}
1890
1569
}
1891
1570
}
1892
1571
1572
/* Set effective uid to 0, return errno */
1573
__attribute__((warn_unused_result))
1574
error_t raise_privileges(void){
1575
error_t old_errno = errno;
1576
error_t ret_errno = 0;
1577
if(seteuid(0) == -1){
1578
ret_errno = errno;
1579
}
1580
errno = old_errno;
1581
return ret_errno;
1582
}
1583
1584
/* Set effective and real user ID to 0. Return errno. */
1585
__attribute__((warn_unused_result))
1586
error_t raise_privileges_permanently(void){
1587
error_t old_errno = errno;
1588
error_t ret_errno = raise_privileges();
1589
if(ret_errno != 0){
1590
errno = old_errno;
1591
return ret_errno;
1592
}
1593
if(setuid(0) == -1){
1594
ret_errno = errno;
1595
}
1596
errno = old_errno;
1597
return ret_errno;
1598
}
1599
1600
/* Set effective user ID to unprivileged saved user ID */
1601
__attribute__((warn_unused_result))
1602
error_t lower_privileges(void){
1603
error_t old_errno = errno;
1604
error_t ret_errno = 0;
1605
if(seteuid(uid) == -1){
1606
ret_errno = errno;
1607
}
1608
errno = old_errno;
1609
return ret_errno;
1610
}
1611
1612
/* Lower privileges permanently */
1613
__attribute__((warn_unused_result))
1614
error_t lower_privileges_permanently(void){
1615
error_t old_errno = errno;
1616
error_t ret_errno = 0;
1617
if(setuid(uid) == -1){
1618
ret_errno = errno;
1619
}
1620
errno = old_errno;
1621
return ret_errno;
1622
}
1623
1893
1624
__attribute__((nonnull))
1894
1625
void run_network_hooks(const char *mode, const char *interface,
1895
1626
const float delay){
1896
1627
struct dirent **direntries = NULL;
1897
1628
if(hookdir_fd == -1){
1898
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1899
| O_CLOEXEC);
1629
hookdir_fd = open(hookdir, O_RDONLY);
1900
1630
if(hookdir_fd == -1){
1901
1631
if(errno == ENOENT){
1902
1632
if(debug){
1909
1639
return;
1910
1640
}
1911
1641
}
1642
#ifdef __GLIBC__
1643
#if __GLIBC_PREREQ(2, 15)
1912
1644
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1913
1645
runnable_hook, alphasort);
1646
#else /* not __GLIBC_PREREQ(2, 15) */
1647
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1648
alphasort);
1649
#endif /* not __GLIBC_PREREQ(2, 15) */
1650
#else /* not __GLIBC__ */
1651
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1652
alphasort);
1653
#endif /* not __GLIBC__ */
1914
1654
if(numhooks == -1){
1915
1655
perror_plus("scandir");
1916
1656
return;
1917
1657
}
1918
1658
struct dirent *direntry;
1919
1659
int ret;
1920
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1921
if(devnull == -1){
1922
perror_plus("open(\"/dev/null\", O_RDONLY)");
1923
return;
1924
}
1660
int devnull = open("/dev/null", O_RDONLY);
1925
1661
for(int i = 0; i < numhooks; i++){
1926
1662
direntry = direntries[i];
1927
1663
if(debug){
1951
1687
perror_plus("setgroups");
1952
1688
_exit(EX_NOPERM);
1953
1689
}
1690
ret = dup2(devnull, STDIN_FILENO);
1691
if(ret == -1){
1692
perror_plus("dup2(devnull, STDIN_FILENO)");
1693
_exit(EX_OSERR);
1694
}
1695
ret = close(devnull);
1696
if(ret == -1){
1697
perror_plus("close");
1698
_exit(EX_OSERR);
1699
}
1700
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1701
if(ret == -1){
1702
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1703
_exit(EX_OSERR);
1704
}
1954
1705
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1955
1706
if(ret == -1){
1956
1707
perror_plus("setenv");
1991
1742
_exit(EX_OSERR);
1992
1743
}
1993
1744
}
1994
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
1995
direntry->d_name,
1996
O_RDONLY));
1745
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1997
1746
if(hook_fd == -1){
1998
1747
perror_plus("openat");
1999
1748
_exit(EXIT_FAILURE);
2000
1749
}
2001
if(close(hookdir_fd) == -1){
1750
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2002
1751
perror_plus("close");
2003
1752
_exit(EXIT_FAILURE);
2004
1753
}
2005
ret = dup2(devnull, STDIN_FILENO);
2006
if(ret == -1){
2007
perror_plus("dup2(devnull, STDIN_FILENO)");
2008
_exit(EX_OSERR);
2009
}
2010
ret = close(devnull);
2011
if(ret == -1){
2012
perror_plus("close");
2013
_exit(EX_OSERR);
2014
}
2015
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2016
if(ret == -1){
2017
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2018
_exit(EX_OSERR);
2019
}
2020
1754
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2021
1755
environ) == -1){
2022
1756
perror_plus("fexecve");
2062
1796
free(direntry);
2063
1797
}
2064
1798
free(direntries);
2065
if(close(hookdir_fd) == -1){
1799
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2066
1800
perror_plus("close");
2067
1801
} else {
2068
1802
hookdir_fd = -1;
2071
1805
}
2072
1806
2073
1807
__attribute__((nonnull, warn_unused_result))
2074
int bring_up_interface(const char *const interface,
2075
const float delay){
2076
int old_errno = errno;
1808
error_t bring_up_interface(const char *const interface,
1809
const float delay){
1810
error_t old_errno = errno;
2077
1811
int ret;
2078
1812
struct ifreq network;
2079
1813
unsigned int if_index = if_nametoindex(interface);
2089
1823
}
2090
1824
2091
1825
if(not interface_is_up(interface)){
2092
int ret_errno = 0;
2093
int ioctl_errno = 0;
1826
error_t ret_errno = 0, ioctl_errno = 0;
2094
1827
if(not get_flags(interface, &network)){
2095
1828
ret_errno = errno;
2096
1829
fprintf_plus(stderr, "Failed to get flags for interface "
2109
1842
}
2110
1843
2111
1844
if(quit_now){
2112
ret = close(sd);
1845
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2113
1846
if(ret == -1){
2114
1847
perror_plus("close");
2115
1848
}
2165
1898
}
2166
1899
2167
1900
/* Close the socket */
2168
ret = close(sd);
1901
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2169
1902
if(ret == -1){
2170
1903
perror_plus("close");
2171
1904
}
2199
1932
}
2200
1933
2201
1934
__attribute__((nonnull, warn_unused_result))
2202
int take_down_interface(const char *const interface){
2203
int old_errno = errno;
1935
error_t take_down_interface(const char *const interface){
1936
error_t old_errno = errno;
2204
1937
struct ifreq network;
2205
1938
unsigned int if_index = if_nametoindex(interface);
2206
1939
if(if_index == 0){
2209
1942
return ENXIO;
2210
1943
}
2211
1944
if(interface_is_up(interface)){
2212
int ret_errno = 0;
2213
int ioctl_errno = 0;
1945
error_t ret_errno = 0, ioctl_errno = 0;
2214
1946
if(not get_flags(interface, &network) and debug){
2215
1947
ret_errno = errno;
2216
1948
fprintf_plus(stderr, "Failed to get flags for interface "
2254
1986
}
2255
1987
2256
1988
/* Close the socket */
2257
int ret = close(sd);
1989
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
2258
1990
if(ret == -1){
2259
1991
perror_plus("close");
2260
1992
}
2276
2008
2277
2009
int main(int argc, char *argv[]){
2278
2010
mandos_context mc = { .server = NULL, .dh_bits = 0,
2279
.priority = "SECURE256:!CTYPE-X.509"
2280
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2281
.current_server = NULL, .interfaces = NULL,
2282
.interfaces_size = 0 };
2011
.priority = "SECURE256:!CTYPE-X.509:"
2012
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
2013
.interfaces = NULL, .interfaces_size = 0 };
2283
2014
AvahiSServiceBrowser *sb = NULL;
2284
2015
error_t ret_errno;
2285
2016
int ret;
2294
2025
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2295
2026
const char *seckey = PATHDIR "/" SECKEY;
2296
2027
const char *pubkey = PATHDIR "/" PUBKEY;
2297
const char *dh_params_file = NULL;
2298
2028
char *interfaces_hooks = NULL;
2299
2029
2300
2030
bool gnutls_initialized = false;
2353
2083
.doc = "Bit length of the prime number used in the"
2354
2084
" Diffie-Hellman key exchange",
2355
2085
.group = 2 },
2356
{ .name = "dh-params", .key = 134,
2357
.arg = "FILE",
2358
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2359
" for the Diffie-Hellman key exchange",
2360
.group = 2 },
2361
2086
{ .name = "priority", .key = 130,
2362
2087
.arg = "STRING",
2363
2088
.doc = "GnuTLS priority string for the TLS handshake",
2418
2143
}
2419
2144
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2420
2145
break;
2421
case 134: /* --dh-params */
2422
dh_params_file = arg;
2423
break;
2424
2146
case 130: /* --priority */
2425
2147
mc.priority = arg;
2426
2148
break;
2466
2188
.args_doc = "",
2467
2189
.doc = "Mandos client -- Get and decrypt"
2468
2190
" passwords from a Mandos server" };
2469
ret_errno = argp_parse(&argp, argc, argv,
2470
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2471
switch(ret_errno){
2191
ret = argp_parse(&argp, argc, argv,
2192
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2193
switch(ret){
2472
2194
case 0:
2473
2195
break;
2474
2196
case ENOMEM:
2475
2197
default:
2476
errno = ret_errno;
2198
errno = ret;
2477
2199
perror_plus("argp_parse");
2478
2200
exitcode = EX_OSERR;
2479
2201
goto end;
2482
2204
goto end;
2483
2205
}
2484
2206
}
2485
2207
2486
2208
{
2487
2209
/* Work around Debian bug #633582:
2488
2210
<http://bugs.debian.org/633582> */
2489
2211
2490
2212
/* Re-raise privileges */
2491
ret = raise_privileges();
2492
if(ret != 0){
2493
errno = ret;
2213
ret_errno = raise_privileges();
2214
if(ret_errno != 0){
2215
errno = ret_errno;
2494
2216
perror_plus("Failed to raise privileges");
2495
2217
} else {
2496
2218
struct stat st;
2512
2234
}
2513
2235
}
2514
2236
}
2515
close(seckey_fd);
2237
TEMP_FAILURE_RETRY(close(seckey_fd));
2516
2238
}
2517
2239
}
2518
2240
2519
2241
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2520
2242
int pubkey_fd = open(pubkey, O_RDONLY);
2521
2243
if(pubkey_fd == -1){
2533
2255
}
2534
2256
}
2535
2257
}
2536
close(pubkey_fd);
2537
}
2538
}
2539
2540
if(dh_params_file != NULL
2541
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2542
int dhparams_fd = open(dh_params_file, O_RDONLY);
2543
if(dhparams_fd == -1){
2544
perror_plus("open");
2545
} else {
2546
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2547
if(ret == -1){
2548
perror_plus("fstat");
2549
} else {
2550
if(S_ISREG(st.st_mode)
2551
and st.st_uid == 0 and st.st_gid == 0){
2552
ret = fchown(dhparams_fd, uid, gid);
2553
if(ret == -1){
2554
perror_plus("fchown");
2555
}
2556
}
2557
}
2558
close(dhparams_fd);
2559
}
2560
}
2561
2258
TEMP_FAILURE_RETRY(close(pubkey_fd));
2259
}
2260
}
2261
2562
2262
/* Lower privileges */
2563
ret = lower_privileges();
2564
if(ret != 0){
2565
errno = ret;
2263
ret_errno = lower_privileges();
2264
if(ret_errno != 0){
2265
errno = ret_errno;
2566
2266
perror_plus("Failed to lower privileges");
2567
2267
}
2568
2268
}
2738
2438
errno = bring_up_interface(interface, delay);
2739
2439
if(not interface_was_up){
2740
2440
if(errno != 0){
2741
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2742
" %s\n", interface, strerror(errno));
2441
perror_plus("Failed to bring up interface");
2743
2442
} else {
2744
2443
errno = argz_add(&interfaces_to_take_down,
2745
2444
&interfaces_to_take_down_size,
2768
2467
goto end;
2769
2468
}
2770
2469
2771
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2470
ret = init_gnutls_global(pubkey, seckey, &mc);
2772
2471
if(ret == -1){
2773
2472
fprintf_plus(stderr, "init_gnutls_global failed\n");
2774
2473
exitcode = EX_UNAVAILABLE;
2896
2595
2897
2596
/* Allocate a new server */
2898
2597
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2899
&config, NULL, NULL, &ret);
2598
&config, NULL, NULL, &ret_errno);
2900
2599
2901
2600
/* Free the Avahi configuration data */
2902
2601
avahi_server_config_free(&config);
2905
2604
/* Check if creating the Avahi server object succeeded */
2906
2605
if(mc.server == NULL){
2907
2606
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2908
avahi_strerror(ret));
2607
avahi_strerror(ret_errno));
2909
2608
exitcode = EX_UNAVAILABLE;
2910
2609
goto end;
2911
2610
}
2963
2662
2964
2663
if(gnutls_initialized){
2965
2664
gnutls_certificate_free_credentials(mc.cred);
2665
gnutls_global_deinit();
2966
2666
gnutls_dh_params_deinit(mc.dh_params);
2967
2667
}
2968
2668
2991
2691
2992
2692
/* Re-raise privileges */
2993
2693
{
2994
ret = raise_privileges();
2995
if(ret != 0){
2996
errno = ret;
2694
ret_errno = raise_privileges();
2695
if(ret_errno != 0){
2696
errno = ret_errno;
2997
2697
perror_plus("Failed to raise privileges");
2998
2698
} else {
2999
2699
3007
2707
while((interface=argz_next(interfaces_to_take_down,
3008
2708
interfaces_to_take_down_size,
3009
2709
interface))){
3010
ret = take_down_interface(interface);
3011
if(ret != 0){
3012
errno = ret;
2710
ret_errno = take_down_interface(interface);
2711
if(ret_errno != 0){
2712
errno = ret_errno;
3013
2713
perror_plus("Failed to take down interface");
3014
2714
}
3015
2715
}
3020
2720
}
3021
2721
}
3022
2722
3023
ret = lower_privileges_permanently();
3024
if(ret != 0){
3025
errno = ret;
2723
ret_errno = lower_privileges_permanently();
2724
if(ret_errno != 0){
2725
errno = ret_errno;
3026
2726
perror_plus("Failed to lower privileges permanently");
3027
2727
}
3028
2728
}
3030
2730
free(interfaces_to_take_down);
3031
2731
free(interfaces_hooks);
3032
2732
3033
void clean_dir_at(int base, const char * const dirname,
3034
uintmax_t level){
3035
struct dirent **direntries = NULL;
3036
int dret;
3037
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3038
O_RDONLY
3039
| O_NOFOLLOW
3040
| O_DIRECTORY
3041
| O_PATH));
3042
if(dir_fd == -1){
3043
perror_plus("open");
3044
}
3045
int numentries = scandirat(dir_fd, ".", &direntries,
3046
notdotentries, alphasort);
3047
if(numentries >= 0){
3048
for(int i = 0; i < numentries; i++){
3049
if(debug){
3050
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3051
dirname, direntries[i]->d_name);
3052
}
3053
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3054
if(dret == -1){
3055
if(errno == EISDIR){
3056
dret = unlinkat(dir_fd, direntries[i]->d_name,
3057
AT_REMOVEDIR);
3058
}
3059
if((dret == -1) and (errno == ENOTEMPTY)
3060
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3061
== 0) and (level == 0)){
3062
/* Recurse only in this special case */
3063
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3064
dret = 0;
3065
}
3066
if(dret == -1){
3067
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3068
direntries[i]->d_name, strerror(errno));
3069
}
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("scandirat");
3078
}
3079
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3080
if(dret == -1 and errno != ENOENT){
3081
perror_plus("rmdir");
3082
}
3083
} else {
3084
perror_plus("scandirat");
3085
}
3086
close(dir_fd);
3087
}
3088
3089
2733
/* Removes the GPGME temp directory and all files inside */
3090
2734
if(tempdir != NULL){
3091
clean_dir_at(-1, tempdir, 0);
2735
struct dirent **direntries = NULL;
2736
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2737
O_NOFOLLOW));
2738
if(tempdir_fd == -1){
2739
perror_plus("open");
2740
} else {
2741
#ifdef __GLIBC__
2742
#if __GLIBC_PREREQ(2, 15)
2743
int numentries = scandirat(tempdir_fd, ".", &direntries,
2744
notdotentries, alphasort);
2745
#else /* not __GLIBC_PREREQ(2, 15) */
2746
int numentries = scandir(tempdir, &direntries, notdotentries,
2747
alphasort);
2748
#endif /* not __GLIBC_PREREQ(2, 15) */
2749
#else /* not __GLIBC__ */
2750
int numentries = scandir(tempdir, &direntries, notdotentries,
2751
alphasort);
2752
#endif /* not __GLIBC__ */
2753
if(numentries >= 0){
2754
for(int i = 0; i < numentries; i++){
2755
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2756
if(ret == -1){
2757
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2758
" \"%s\", 0): %s\n", tempdir,
2759
direntries[i]->d_name, strerror(errno));
2760
}
2761
free(direntries[i]);
2762
}
2763
2764
/* need to clean even if 0 because man page doesn't specify */
2765
free(direntries);
2766
if(numentries == -1){
2767
perror_plus("scandir");
2768
}
2769
ret = rmdir(tempdir);
2770
if(ret == -1 and errno != ENOENT){
2771
perror_plus("rmdir");
2772
}
2773
}
2774
TEMP_FAILURE_RETRY(close(tempdir_fd));
2775
}
3092
2776
}
3093
2777
3094
2778
if(quit_now){
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0