621
501
/* Called when a Mandos server is found */
622
502
static int start_mandos_communication(const char *ip, uint16_t port,
623
503
AvahiIfIndex if_index,
625
int ret, tcp_sd = -1;
628
struct sockaddr_in in;
629
struct sockaddr_in6 in6;
506
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
631
507
char *buffer = NULL;
632
char *decrypted_buffer = NULL;
508
char *decrypted_buffer;
633
509
size_t buffer_length = 0;
634
510
size_t buffer_capacity = 0;
511
ssize_t decrypted_buffer_size;
514
char interface[IF_NAMESIZE];
637
515
gnutls_session_t session;
638
int pf; /* Protocol family */
655
fprintf_plus(stderr, "Bad address family: %d\n", af);
660
ret = init_gnutls_session(&session);
666
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
667
PRIu16 "\n", ip, port);
670
tcp_sd = socket(pf, SOCK_STREAM, 0);
673
perror_plus("socket");
517
ret = init_gnutls_session (mc, &session);
523
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
527
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
534
if(if_indextoname((unsigned int)if_index, interface) == NULL){
535
perror("if_indextoname");
538
fprintf(stderr, "Binding to interface %s\n", interface);
683
541
memset(&to, 0, sizeof(to));
685
to.in6.sin6_family = (sa_family_t)af;
686
ret = inet_pton(af, ip, &to.in6.sin6_addr);
688
to.in.sin_family = (sa_family_t)af;
689
ret = inet_pton(af, ip, &to.in.sin_addr);
693
perror_plus("inet_pton");
542
to.in6.sin6_family = AF_INET6;
543
/* It would be nice to have a way to detect if we were passed an
544
IPv4 address here. Now we assume an IPv6 address. */
545
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
699
fprintf_plus(stderr, "Bad address: %s\n", ip);
704
to.in6.sin6_port = htons(port); /* Spurious warnings from
706
-Wunreachable-code */
708
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
709
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
711
if(if_index == AVAHI_IF_UNSPEC){
712
fprintf_plus(stderr, "An IPv6 link-local address is"
713
" incomplete without a network interface\n");
717
/* Set the network interface number as scope */
718
to.in6.sin6_scope_id = (uint32_t)if_index;
721
to.in.sin_port = htons(port); /* Spurious warnings from
723
-Wunreachable-code */
551
fprintf(stderr, "Bad address: %s\n", ip);
554
to.in6.sin6_port = htons(port); /* Spurious warning */
556
to.in6.sin6_scope_id = (uint32_t)if_index;
732
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
733
char interface[IF_NAMESIZE];
734
if(if_indextoname((unsigned int)if_index, interface) == NULL){
735
perror_plus("if_indextoname");
737
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
738
"\n", ip, interface, port);
741
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
744
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
745
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
748
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
751
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
755
perror_plus("inet_ntop");
559
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
561
char addrstr[INET6_ADDRSTRLEN] = "";
562
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
563
sizeof(addrstr)) == NULL){
757
566
if(strcmp(addrstr, ip) != 0){
758
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
567
fprintf(stderr, "Canonical address form: %s\n", addrstr);
769
ret = connect(tcp_sd, &to.in6, sizeof(to));
771
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
774
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
776
perror_plus("connect");
572
ret = connect(tcp_sd, &to.in, sizeof(to));
787
578
const char *out = mandos_protocol_version;
790
581
size_t out_size = strlen(out);
791
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
792
out_size - written));
795
perror_plus("write");
582
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
583
out_size - written));
799
589
written += (size_t)ret;
800
590
if(written < out_size){
803
if(out == mandos_protocol_version){
593
if (out == mandos_protocol_version){
818
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
826
/* This casting via intptr_t is to eliminate warning about casting
827
an int to a pointer type. This is exactly how the GnuTLS Guile
828
function "set-session-transport-fd!" does it. */
829
gnutls_transport_set_ptr(session,
830
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
838
ret = gnutls_handshake(session);
603
fprintf(stderr, "Establishing TLS session with %s\n", ip);
606
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
609
ret = gnutls_handshake (session);
843
610
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
845
if(ret != GNUTLS_E_SUCCESS){
612
if (ret != GNUTLS_E_SUCCESS){
847
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
614
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
854
621
/* Read OpenPGP packet that contains the wanted password */
857
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
624
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
868
buffer_capacity = incbuffer(&buffer, buffer_length,
870
if(buffer_capacity == 0){
872
perror_plus("incbuffer");
882
sret = gnutls_record_recv(session, buffer+buffer_length,
629
buffer_capacity = adjustbuffer(&buffer, buffer_length,
631
if (buffer_capacity == 0){
632
perror("adjustbuffer");
637
ret = gnutls_record_recv(session, buffer+buffer_length,
889
644
case GNUTLS_E_INTERRUPTED:
890
645
case GNUTLS_E_AGAIN:
892
647
case GNUTLS_E_REHANDSHAKE:
894
ret = gnutls_handshake(session);
649
ret = gnutls_handshake (session);
900
650
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
902
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
652
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
910
fprintf_plus(stderr, "Unknown error while reading data from"
911
" encrypted session with Mandos server\n");
912
gnutls_bye(session, GNUTLS_SHUT_RDWR);
659
fprintf(stderr, "Unknown error while reading data from"
660
" encrypted session with Mandos server\n");
662
gnutls_bye (session, GNUTLS_SHUT_RDWR);
917
buffer_length += (size_t) sret;
666
buffer_length += (size_t) ret;
922
fprintf_plus(stderr, "Closing TLS session\n");
931
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
936
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
938
if(buffer_length > 0){
939
ssize_t decrypted_buffer_size;
940
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
671
fprintf(stderr, "Closing TLS session\n");
674
gnutls_bye (session, GNUTLS_SHUT_RDWR);
676
if (buffer_length > 0){
677
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
941
679
&decrypted_buffer);
942
if(decrypted_buffer_size >= 0){
680
if (decrypted_buffer_size >= 0){
945
682
while(written < (size_t) decrypted_buffer_size){
951
ret = (int)fwrite(decrypted_buffer + written, 1,
952
(size_t)decrypted_buffer_size - written,
683
ret = (int)fwrite (decrypted_buffer + written, 1,
684
(size_t)decrypted_buffer_size - written,
954
686
if(ret == 0 and ferror(stdout)){
957
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
688
fprintf(stderr, "Error writing encrypted data: %s\n",
963
694
written += (size_t)ret;
696
free(decrypted_buffer);
969
704
/* Shutdown procedure */
974
free(decrypted_buffer);
977
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
983
perror_plus("close");
985
gnutls_deinit(session);
708
ret = TEMP_FAILURE_RETRY(close(tcp_sd));
712
gnutls_deinit (session);
995
716
static void resolve_callback(AvahiSServiceResolver *r,
996
717
AvahiIfIndex interface,
718
AVAHI_GCC_UNUSED AvahiProtocol protocol,
998
719
AvahiResolverEvent event,
999
720
const char *name,
1000
721
const char *type,
1097
804
case AVAHI_BROWSER_ALL_FOR_NOW:
1098
805
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1100
fprintf_plus(stderr, "No Mandos server found, still"
807
fprintf(stderr, "No Mandos server found, still searching...\n");
1107
/* Signal handler that stops main loop after SIGTERM */
1108
static void handle_sigterm(int sig){
1113
signal_received = sig;
1114
int old_errno = errno;
1115
/* set main loop to exit */
1116
if(mc.simple_poll != NULL){
1117
avahi_simple_poll_quit(mc.simple_poll);
1122
bool get_flags(const char *ifname, struct ifreq *ifr){
1125
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1127
perror_plus("socket");
1130
strcpy(ifr->ifr_name, ifname);
1131
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1134
perror_plus("ioctl SIOCGIFFLAGS");
1141
bool good_flags(const char *ifname, const struct ifreq *ifr){
1143
/* Reject the loopback device */
1144
if(ifr->ifr_flags & IFF_LOOPBACK){
1146
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1151
/* Accept point-to-point devices only if connect_to is specified */
1152
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1154
fprintf_plus(stderr, "Accepting point-to-point interface"
1155
" \"%s\"\n", ifname);
1159
/* Otherwise, reject non-broadcast-capable devices */
1160
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1162
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1163
" \"%s\"\n", ifname);
1167
/* Reject non-ARP interfaces (including dummy interfaces) */
1168
if(ifr->ifr_flags & IFF_NOARP){
1170
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1176
/* Accept this device */
1178
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1184
* This function determines if a directory entry in /sys/class/net
1185
* corresponds to an acceptable network device.
1186
* (This function is passed to scandir(3) as a filter function.)
1188
int good_interface(const struct dirent *if_entry){
1189
if(if_entry->d_name[0] == '.'){
1194
if(not get_flags(if_entry->d_name, &ifr)){
1196
fprintf_plus(stderr, "Failed to get flags for interface "
1197
"\"%s\"\n", if_entry->d_name);
1202
if(not good_flags(if_entry->d_name, &ifr)){
1209
* This function determines if a directory entry in /sys/class/net
1210
* corresponds to an acceptable network device which is up.
1211
* (This function is passed to scandir(3) as a filter function.)
1213
int up_interface(const struct dirent *if_entry){
1214
if(if_entry->d_name[0] == '.'){
1219
if(not get_flags(if_entry->d_name, &ifr)){
1221
fprintf_plus(stderr, "Failed to get flags for interface "
1222
"\"%s\"\n", if_entry->d_name);
1227
/* Reject down interfaces */
1228
if(not (ifr.ifr_flags & IFF_UP)){
1230
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1236
/* Reject non-running interfaces */
1237
if(not (ifr.ifr_flags & IFF_RUNNING)){
1239
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1245
if(not good_flags(if_entry->d_name, &ifr)){
1251
int notdotentries(const struct dirent *direntry){
1252
/* Skip "." and ".." */
1253
if(direntry->d_name[0] == '.'
1254
and (direntry->d_name[1] == '\0'
1255
or (direntry->d_name[1] == '.'
1256
and direntry->d_name[2] == '\0'))){
1262
/* Is this directory entry a runnable program? */
1263
int runnable_hook(const struct dirent *direntry){
1268
if((direntry->d_name)[0] == '\0'){
1273
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1274
"abcdefghijklmnopqrstuvwxyz"
1277
if((direntry->d_name)[sret] != '\0'){
1278
/* Contains non-allowed characters */
1280
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1286
char *fullname = NULL;
1287
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1289
perror_plus("asprintf");
1293
ret = stat(fullname, &st);
1296
perror_plus("Could not stat hook");
1300
if(not (S_ISREG(st.st_mode))){
1301
/* Not a regular file */
1303
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1308
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1309
/* Not executable */
1311
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1317
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1323
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1325
struct timespec now;
1326
struct timespec waited_time;
1327
intmax_t block_time;
1330
if(mc.current_server == NULL){
1332
fprintf_plus(stderr, "Wait until first server is found."
1335
ret = avahi_simple_poll_iterate(s, -1);
1338
fprintf_plus(stderr, "Check current_server if we should run"
1341
/* the current time */
1342
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1344
perror_plus("clock_gettime");
1347
/* Calculating in ms how long time between now and server
1348
who we visted longest time ago. Now - last seen. */
1349
waited_time.tv_sec = (now.tv_sec
1350
- mc.current_server->last_seen.tv_sec);
1351
waited_time.tv_nsec = (now.tv_nsec
1352
- mc.current_server->last_seen.tv_nsec);
1353
/* total time is 10s/10,000ms.
1354
Converting to s from ms by dividing by 1,000,
1355
and ns to ms by dividing by 1,000,000. */
1356
block_time = ((retry_interval
1357
- ((intmax_t)waited_time.tv_sec * 1000))
1358
- ((intmax_t)waited_time.tv_nsec / 1000000));
1361
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1365
if(block_time <= 0){
1366
ret = start_mandos_communication(mc.current_server->ip,
1367
mc.current_server->port,
1368
mc.current_server->if_index,
1369
mc.current_server->af);
1371
avahi_simple_poll_quit(mc.simple_poll);
1374
ret = clock_gettime(CLOCK_MONOTONIC,
1375
&mc.current_server->last_seen);
1377
perror_plus("clock_gettime");
1380
mc.current_server = mc.current_server->next;
1381
block_time = 0; /* Call avahi to find new Mandos
1382
servers, but don't block */
1385
ret = avahi_simple_poll_iterate(s, (int)block_time);
1388
if (ret > 0 or errno != EINTR){
1389
return (ret != 1) ? ret : 0;
1395
/* Set effective uid to 0, return errno */
1396
int raise_privileges(void){
1397
int old_errno = errno;
1400
if(seteuid(0) == -1){
1401
perror_plus("seteuid");
1408
/* Set effective and real user ID to 0. Return errno. */
1409
int raise_privileges_permanently(void){
1410
int old_errno = errno;
1411
int ret_errno = raise_privileges();
1417
if(setuid(0) == -1){
1418
perror_plus("seteuid");
1425
/* Set effective user ID to unprivileged saved user ID */
1426
int lower_privileges(void){
1427
int old_errno = errno;
1430
if(seteuid(uid) == -1){
1431
perror_plus("seteuid");
1438
bool run_network_hooks(const char *mode, const char *interface,
1440
struct dirent **direntries;
1441
struct dirent *direntry;
1443
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1446
perror_plus("scandir");
1448
int devnull = open("/dev/null", O_RDONLY);
1449
for(int i = 0; i < numhooks; i++){
1450
direntry = direntries[i];
1451
char *fullname = NULL;
1452
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1454
perror_plus("asprintf");
1458
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1461
pid_t hook_pid = fork();
1464
/* Raise privileges */
1465
raise_privileges_permanently();
1470
perror_plus("setgid");
1472
/* Reset supplementary groups */
1474
ret = setgroups(0, NULL);
1476
perror_plus("setgroups");
1478
dup2(devnull, STDIN_FILENO);
1480
dup2(STDERR_FILENO, STDOUT_FILENO);
1481
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1483
perror_plus("setenv");
1486
ret = setenv("DEVICE", interface, 1);
1488
perror_plus("setenv");
1491
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1493
perror_plus("setenv");
1496
ret = setenv("MODE", mode, 1);
1498
perror_plus("setenv");
1502
ret = asprintf(&delaystring, "%f", delay);
1504
perror_plus("asprintf");
1507
ret = setenv("DELAY", delaystring, 1);
1510
perror_plus("setenv");
1514
if(connect_to != NULL){
1515
ret = setenv("CONNECT", connect_to, 1);
1517
perror_plus("setenv");
1521
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1522
perror_plus("execl");
1523
_exit(EXIT_FAILURE);
1527
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1528
perror_plus("waitpid");
1532
if(WIFEXITED(status)){
1533
if(WEXITSTATUS(status) != 0){
1534
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1535
" with status %d\n", direntry->d_name,
1536
WEXITSTATUS(status));
1540
} else if(WIFSIGNALED(status)){
1541
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1542
" signal %d\n", direntry->d_name,
1547
fprintf_plus(stderr, "Warning: network hook \"%s\""
1548
" crashed\n", direntry->d_name);
1555
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1564
int bring_up_interface(const char * const interface, const float delay){
1566
int old_errno = errno;
1569
struct ifreq network;
1570
AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);
1572
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1582
/* Re-raise priviliges */
1586
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1587
messages about the network interface to mess up the prompt */
1588
ret = klogctl(8, NULL, 5);
1589
bool restore_loglevel = true;
1591
restore_loglevel = false;
1592
perror_plus("klogctl");
1594
#endif /* __linux__ */
1596
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1599
perror_plus("socket");
1601
if(restore_loglevel){
1602
ret = klogctl(7, NULL, 0);
1604
perror_plus("klogctl");
1607
#endif /* __linux__ */
1608
/* Lower privileges */
1613
strcpy(network.ifr_name, interface);
1614
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1617
perror_plus("ioctl SIOCGIFFLAGS");
1619
if(restore_loglevel){
1620
ret = klogctl(7, NULL, 0);
1622
perror_plus("klogctl");
1625
#endif /* __linux__ */
1626
/* Lower privileges */
1631
if((network.ifr_flags & IFF_UP) == 0){
1632
network.ifr_flags |= IFF_UP;
1633
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1636
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1638
if(restore_loglevel){
1639
ret = klogctl(7, NULL, 0);
1641
perror_plus("klogctl");
1644
#endif /* __linux__ */
1645
/* Lower privileges */
1651
/* Sleep checking until interface is running.
1652
Check every 0.25s, up to total time of delay */
1653
for(int i=0; i < delay * 4; i++){
1654
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1656
perror_plus("ioctl SIOCGIFFLAGS");
1657
} else if(network.ifr_flags & IFF_RUNNING){
1660
struct timespec sleeptime = { .tv_nsec = 250000000 };
1661
ret = nanosleep(&sleeptime, NULL);
1662
if(ret == -1 and errno != EINTR){
1663
perror_plus("nanosleep");
1666
/* Close the socket */
1667
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1669
perror_plus("close");
1672
if(restore_loglevel){
1673
/* Restores kernel loglevel to default */
1674
ret = klogctl(7, NULL, 0);
1676
perror_plus("klogctl");
1679
#endif /* __linux__ */
1680
/* Lower privileges */
1686
813
int main(int argc, char *argv[]){
1687
AvahiSServiceBrowser *sb = NULL;
1692
int exitcode = EXIT_SUCCESS;
1693
const char *interface = "";
1694
struct ifreq network;
1696
bool take_down_interface = false;
1697
char tempdir[] = "/tmp/mandosXXXXXX";
1698
bool tempdir_created = false;
1699
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1700
const char *seckey = PATHDIR "/" SECKEY;
1701
const char *pubkey = PATHDIR "/" PUBKEY;
1703
bool gnutls_initialized = false;
1704
bool gpgme_initialized = false;
1706
double retry_interval = 10; /* 10s between trying a server and
1707
retrying the same server again */
1709
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1710
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1715
/* Lower any group privileges we might have, just to be safe */
1719
perror_plus("setgid");
1722
/* Lower user privileges (temporarily) */
1726
perror_plus("seteuid");
1734
struct argp_option options[] = {
1735
{ .name = "debug", .key = 128,
1736
.doc = "Debug mode", .group = 3 },
1737
{ .name = "connect", .key = 'c',
1738
.arg = "ADDRESS:PORT",
1739
.doc = "Connect directly to a specific Mandos server",
1741
{ .name = "interface", .key = 'i',
1743
.doc = "Network interface that will be used to search for"
1746
{ .name = "seckey", .key = 's',
1748
.doc = "OpenPGP secret key file base name",
1750
{ .name = "pubkey", .key = 'p',
1752
.doc = "OpenPGP public key file base name",
1754
{ .name = "dh-bits", .key = 129,
1756
.doc = "Bit length of the prime number used in the"
1757
" Diffie-Hellman key exchange",
1759
{ .name = "priority", .key = 130,
1761
.doc = "GnuTLS priority string for the TLS handshake",
1763
{ .name = "delay", .key = 131,
1765
.doc = "Maximum delay to wait for interface startup",
1767
{ .name = "retry", .key = 132,
1769
.doc = "Retry interval used when denied by the Mandos server",
1771
{ .name = "network-hook-dir", .key = 133,
1773
.doc = "Directory where network hooks are located",
1776
* These reproduce what we would get without ARGP_NO_HELP
1778
{ .name = "help", .key = '?',
1779
.doc = "Give this help list", .group = -1 },
1780
{ .name = "usage", .key = -3,
1781
.doc = "Give a short usage message", .group = -1 },
1782
{ .name = "version", .key = 'V',
1783
.doc = "Print program version", .group = -1 },
1787
error_t parse_opt(int key, char *arg,
1788
struct argp_state *state){
1791
case 128: /* --debug */
1794
case 'c': /* --connect */
1797
case 'i': /* --interface */
1800
case 's': /* --seckey */
1803
case 'p': /* --pubkey */
1806
case 129: /* --dh-bits */
1808
tmpmax = strtoimax(arg, &tmp, 10);
1809
if(errno != 0 or tmp == arg or *tmp != '\0'
1810
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1811
argp_error(state, "Bad number of DH bits");
1813
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1815
case 130: /* --priority */
1818
case 131: /* --delay */
1820
delay = strtof(arg, &tmp);
1821
if(errno != 0 or tmp == arg or *tmp != '\0'){
1822
argp_error(state, "Bad delay");
1824
case 132: /* --retry */
1826
retry_interval = strtod(arg, &tmp);
1827
if(errno != 0 or tmp == arg or *tmp != '\0'
1828
or (retry_interval * 1000) > INT_MAX
1829
or retry_interval < 0){
1830
argp_error(state, "Bad retry interval");
1833
case 133: /* --network-hook-dir */
1837
* These reproduce what we would get without ARGP_NO_HELP
1839
case '?': /* --help */
1840
argp_state_help(state, state->out_stream,
1841
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1842
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1843
case -3: /* --usage */
1844
argp_state_help(state, state->out_stream,
1845
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1846
case 'V': /* --version */
1847
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1848
exit(argp_err_exit_status);
1851
return ARGP_ERR_UNKNOWN;
1856
struct argp argp = { .options = options, .parser = parse_opt,
1858
.doc = "Mandos client -- Get and decrypt"
1859
" passwords from a Mandos server" };
1860
ret = argp_parse(&argp, argc, argv,
1861
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1868
perror_plus("argp_parse");
1869
exitcode = EX_OSERR;
1872
exitcode = EX_USAGE;
1878
/* Work around Debian bug #633582:
1879
<http://bugs.debian.org/633582> */
1881
/* Re-raise priviliges */
1882
if(raise_privileges() == 0){
1885
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1886
int seckey_fd = open(seckey, O_RDONLY);
1887
if(seckey_fd == -1){
1888
perror_plus("open");
1890
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1892
perror_plus("fstat");
1894
if(S_ISREG(st.st_mode)
1895
and st.st_uid == 0 and st.st_gid == 0){
1896
ret = fchown(seckey_fd, uid, gid);
1898
perror_plus("fchown");
1902
TEMP_FAILURE_RETRY(close(seckey_fd));
1906
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1907
int pubkey_fd = open(pubkey, O_RDONLY);
1908
if(pubkey_fd == -1){
1909
perror_plus("open");
1911
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1913
perror_plus("fstat");
1915
if(S_ISREG(st.st_mode)
1916
and st.st_uid == 0 and st.st_gid == 0){
1917
ret = fchown(pubkey_fd, uid, gid);
1919
perror_plus("fchown");
1923
TEMP_FAILURE_RETRY(close(pubkey_fd));
1927
/* Lower privileges */
1931
perror_plus("seteuid");
1936
/* Run network hooks */
1937
if(not run_network_hooks("start", interface, delay)){
1942
avahi_set_log_function(empty_log);
1945
if(interface[0] == '\0'){
1946
struct dirent **direntries;
1947
/* First look for interfaces that are up */
1948
ret = scandir(sys_class_net, &direntries, up_interface,
1951
/* No up interfaces, look for any good interfaces */
1953
ret = scandir(sys_class_net, &direntries, good_interface,
1957
/* Pick the first interface returned */
1958
interface = strdup(direntries[0]->d_name);
1960
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1962
if(interface == NULL){
1963
perror_plus("malloc");
814
AvahiSServiceBrowser *sb = NULL;
817
int exitcode = EXIT_SUCCESS;
818
const char *interface = "eth0";
819
struct ifreq network;
823
char *connect_to = NULL;
824
char tempdir[] = "/tmp/mandosXXXXXX";
825
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
826
const char *seckey = PATHDIR "/" SECKEY;
827
const char *pubkey = PATHDIR "/" PUBKEY;
829
mandos_context mc = { .simple_poll = NULL, .server = NULL,
830
.dh_bits = 1024, .priority = "SECURE256"
831
":!CTYPE-X.509:+CTYPE-OPENPGP" };
832
bool gnutls_initalized = false;
833
bool pgpme_initalized = false;
836
struct argp_option options[] = {
837
{ .name = "debug", .key = 128,
838
.doc = "Debug mode", .group = 3 },
839
{ .name = "connect", .key = 'c',
840
.arg = "ADDRESS:PORT",
841
.doc = "Connect directly to a specific Mandos server",
843
{ .name = "interface", .key = 'i',
845
.doc = "Interface that will be used to search for Mandos"
848
{ .name = "seckey", .key = 's',
850
.doc = "OpenPGP secret key file base name",
852
{ .name = "pubkey", .key = 'p',
854
.doc = "OpenPGP public key file base name",
856
{ .name = "dh-bits", .key = 129,
858
.doc = "Bit length of the prime number used in the"
859
" Diffie-Hellman key exchange",
861
{ .name = "priority", .key = 130,
863
.doc = "GnuTLS priority string for the TLS handshake",
868
error_t parse_opt (int key, char *arg,
869
struct argp_state *state) {
870
/* Get the INPUT argument from `argp_parse', which we know is
871
a pointer to our plugin list pointer. */
873
case 128: /* --debug */
876
case 'c': /* --connect */
879
case 'i': /* --interface */
882
case 's': /* --seckey */
885
case 'p': /* --pubkey */
888
case 129: /* --dh-bits */
890
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
896
case 130: /* --priority */
904
return ARGP_ERR_UNKNOWN;
909
struct argp argp = { .options = options, .parser = parse_opt,
911
.doc = "Mandos client -- Get and decrypt"
912
" passwords from a Mandos server" };
913
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
914
if (ret == ARGP_ERR_UNKNOWN){
915
fprintf(stderr, "Unknown error while parsing arguments\n");
1965
916
exitcode = EXIT_FAILURE;
1971
fprintf_plus(stderr, "Could not find a network interface\n");
921
ret = init_gnutls_global(&mc, pubkey, seckey);
923
fprintf(stderr, "init_gnutls_global failed\n");
1972
924
exitcode = EXIT_FAILURE;
1977
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1978
from the signal handler */
1979
/* Initialize the pseudo-RNG for Avahi */
1980
srand((unsigned int) time(NULL));
1981
mc.simple_poll = avahi_simple_poll_new();
1982
if(mc.simple_poll == NULL){
1983
fprintf_plus(stderr,
1984
"Avahi: Failed to create simple poll object.\n");
1985
exitcode = EX_UNAVAILABLE;
1989
sigemptyset(&sigterm_action.sa_mask);
1990
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1992
perror_plus("sigaddset");
1993
exitcode = EX_OSERR;
1996
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1998
perror_plus("sigaddset");
1999
exitcode = EX_OSERR;
2002
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2004
perror_plus("sigaddset");
2005
exitcode = EX_OSERR;
2008
/* Need to check if the handler is SIG_IGN before handling:
2009
| [[info:libc:Initial Signal Actions]] |
2010
| [[info:libc:Basic Signal Handling]] |
2012
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2014
perror_plus("sigaction");
2017
if(old_sigterm_action.sa_handler != SIG_IGN){
2018
ret = sigaction(SIGINT, &sigterm_action, NULL);
2020
perror_plus("sigaction");
2021
exitcode = EX_OSERR;
2025
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2027
perror_plus("sigaction");
2030
if(old_sigterm_action.sa_handler != SIG_IGN){
2031
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2033
perror_plus("sigaction");
2034
exitcode = EX_OSERR;
2038
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2040
perror_plus("sigaction");
2043
if(old_sigterm_action.sa_handler != SIG_IGN){
2044
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2046
perror_plus("sigaction");
2047
exitcode = EX_OSERR;
2052
/* If the interface is down, bring it up */
2053
if((interface[0] != '\0') and (strcmp(interface, "none") != 0)){
2054
ret = bring_up_interface(interface, delay);
2057
perror_plus("Failed to bring up interface");
2065
ret = init_gnutls_global(pubkey, seckey);
2067
fprintf_plus(stderr, "init_gnutls_global failed\n");
2068
exitcode = EX_UNAVAILABLE;
2071
gnutls_initialized = true;
2078
if(mkdtemp(tempdir) == NULL){
2079
perror_plus("mkdtemp");
2082
tempdir_created = true;
2088
if(not init_gpgme(pubkey, seckey, tempdir)){
2089
fprintf_plus(stderr, "init_gpgme failed\n");
2090
exitcode = EX_UNAVAILABLE;
2093
gpgme_initialized = true;
2100
if(connect_to != NULL){
2101
/* Connect directly, do not use Zeroconf */
2102
/* (Mainly meant for debugging) */
2103
char *address = strrchr(connect_to, ':');
2105
if(address == NULL){
2106
fprintf_plus(stderr, "No colon in address\n");
2107
exitcode = EX_USAGE;
2117
tmpmax = strtoimax(address+1, &tmp, 10);
2118
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2119
or tmpmax != (uint16_t)tmpmax){
2120
fprintf_plus(stderr, "Bad port number\n");
2121
exitcode = EX_USAGE;
2129
port = (uint16_t)tmpmax;
2131
/* Colon in address indicates IPv6 */
2133
if(strchr(connect_to, ':') != NULL){
2135
/* Accept [] around IPv6 address - see RFC 5952 */
2136
if(connect_to[0] == '[' and address[-1] == ']')
2144
address = connect_to;
2150
while(not quit_now){
2151
ret = start_mandos_communication(address, port, if_index, af);
2152
if(quit_now or ret == 0){
2156
fprintf_plus(stderr, "Retrying in %d seconds\n",
2157
(int)retry_interval);
2159
sleep((int)retry_interval);
2163
exitcode = EXIT_SUCCESS;
2174
AvahiServerConfig config;
2175
/* Do not publish any local Zeroconf records */
2176
avahi_server_config_init(&config);
2177
config.publish_hinfo = 0;
2178
config.publish_addresses = 0;
2179
config.publish_workstation = 0;
2180
config.publish_domain = 0;
2182
/* Allocate a new server */
2183
mc.server = avahi_server_new(avahi_simple_poll_get
2184
(mc.simple_poll), &config, NULL,
2187
/* Free the Avahi configuration data */
2188
avahi_server_config_free(&config);
2191
/* Check if creating the Avahi server object succeeded */
2192
if(mc.server == NULL){
2193
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2194
avahi_strerror(error));
2195
exitcode = EX_UNAVAILABLE;
2203
/* Create the Avahi service browser */
2204
sb = avahi_s_service_browser_new(mc.server, if_index,
2205
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2206
NULL, 0, browse_callback, NULL);
2208
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2209
avahi_strerror(avahi_server_errno(mc.server)));
2210
exitcode = EX_UNAVAILABLE;
2218
/* Run the main loop */
2221
fprintf_plus(stderr, "Starting Avahi loop search\n");
927
gnutls_initalized = true;
2224
ret = avahi_loop_with_timeout(mc.simple_poll,
2225
(int)(retry_interval * 1000));
2227
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2228
(ret == 0) ? "successfully" : "with error");
2234
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2237
/* Cleanup things */
2239
avahi_s_service_browser_free(sb);
2241
if(mc.server != NULL)
2242
avahi_server_free(mc.server);
2244
if(mc.simple_poll != NULL)
2245
avahi_simple_poll_free(mc.simple_poll);
2247
if(gnutls_initialized){
2248
gnutls_certificate_free_credentials(mc.cred);
2249
gnutls_global_deinit();
2250
gnutls_dh_params_deinit(mc.dh_params);
2253
if(gpgme_initialized){
2254
gpgme_release(mc.ctx);
2257
/* Cleans up the circular linked list of Mandos servers the client
2259
if(mc.current_server != NULL){
2260
mc.current_server->prev->next = NULL;
2261
while(mc.current_server != NULL){
2262
server *next = mc.current_server->next;
2263
free(mc.current_server);
2264
mc.current_server = next;
2268
/* Run network hooks */
2269
run_network_hooks("stop", interface, delay);
2271
/* Re-raise priviliges */
2275
/* Take down the network interface */
2276
if(take_down_interface and geteuid() == 0){
930
if(mkdtemp(tempdir) == NULL){
936
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
937
fprintf(stderr, "pgpme_initalized failed\n");
938
exitcode = EXIT_FAILURE;
941
pgpme_initalized = true;
944
/* If the interface is down, bring it up */
946
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
949
exitcode = EXIT_FAILURE;
952
strcpy(network.ifr_name, interface);
2277
953
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2279
perror_plus("ioctl SIOCGIFFLAGS");
2280
} else if(network.ifr_flags & IFF_UP){
2281
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
955
perror("ioctl SIOCGIFFLAGS");
956
exitcode = EXIT_FAILURE;
959
if((network.ifr_flags & IFF_UP) == 0){
960
network.ifr_flags |= IFF_UP;
2282
961
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2284
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2287
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2289
perror_plus("close");
2293
/* Lower privileges permanently */
2297
perror_plus("setuid");
2300
/* Removes the GPGME temp directory and all files inside */
2301
if(tempdir_created){
2302
struct dirent **direntries = NULL;
2303
struct dirent *direntry = NULL;
2304
int numentries = scandir(tempdir, &direntries, notdotentries,
2306
if (numentries > 0){
2307
for(int i = 0; i < numentries; i++){
2308
direntry = direntries[i];
2309
char *fullname = NULL;
2310
ret = asprintf(&fullname, "%s/%s", tempdir,
2313
perror_plus("asprintf");
2316
ret = remove(fullname);
2318
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2325
/* need to clean even if 0 because man page doesn't specify */
2327
if (numentries == -1){
2328
perror_plus("scandir");
2330
ret = rmdir(tempdir);
2331
if(ret == -1 and errno != ENOENT){
2332
perror_plus("rmdir");
2337
sigemptyset(&old_sigterm_action.sa_mask);
2338
old_sigterm_action.sa_handler = SIG_DFL;
2339
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2340
&old_sigterm_action,
2343
perror_plus("sigaction");
2346
ret = raise(signal_received);
2347
} while(ret != 0 and errno == EINTR);
2349
perror_plus("raise");
2352
TEMP_FAILURE_RETRY(pause());
963
perror("ioctl SIOCSIFFLAGS");
964
exitcode = EXIT_FAILURE;
968
ret = TEMP_FAILURE_RETRY(close(sd));
987
if_index = (AvahiIfIndex) if_nametoindex(interface);
989
fprintf(stderr, "No such interface: \"%s\"\n", interface);
993
if(connect_to != NULL){
994
/* Connect directly, do not use Zeroconf */
995
/* (Mainly meant for debugging) */
996
char *address = strrchr(connect_to, ':');
998
fprintf(stderr, "No colon in address\n");
999
exitcode = EXIT_FAILURE;
1003
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1005
perror("Bad port number");
1006
exitcode = EXIT_FAILURE;
1010
address = connect_to;
1011
ret = start_mandos_communication(address, port, if_index, &mc);
1013
exitcode = EXIT_FAILURE;
1015
exitcode = EXIT_SUCCESS;
1021
avahi_set_log_function(empty_log);
1024
/* Initialize the pseudo-RNG for Avahi */
1025
srand((unsigned int) time(NULL));
1027
/* Allocate main Avahi loop object */
1028
mc.simple_poll = avahi_simple_poll_new();
1029
if (mc.simple_poll == NULL) {
1030
fprintf(stderr, "Avahi: Failed to create simple poll"
1032
exitcode = EXIT_FAILURE;
1037
AvahiServerConfig config;
1038
/* Do not publish any local Zeroconf records */
1039
avahi_server_config_init(&config);
1040
config.publish_hinfo = 0;
1041
config.publish_addresses = 0;
1042
config.publish_workstation = 0;
1043
config.publish_domain = 0;
1045
/* Allocate a new server */
1046
mc.server = avahi_server_new(avahi_simple_poll_get
1047
(mc.simple_poll), &config, NULL,
1050
/* Free the Avahi configuration data */
1051
avahi_server_config_free(&config);
1054
/* Check if creating the Avahi server object succeeded */
1055
if (mc.server == NULL) {
1056
fprintf(stderr, "Failed to create Avahi server: %s\n",
1057
avahi_strerror(error));
1058
exitcode = EXIT_FAILURE;
1062
/* Create the Avahi service browser */
1063
sb = avahi_s_service_browser_new(mc.server, if_index,
1065
"_mandos._tcp", NULL, 0,
1066
browse_callback, &mc);
1068
fprintf(stderr, "Failed to create service browser: %s\n",
1069
avahi_strerror(avahi_server_errno(mc.server)));
1070
exitcode = EXIT_FAILURE;
1074
/* Run the main loop */
1077
fprintf(stderr, "Starting Avahi loop search\n");
1080
avahi_simple_poll_loop(mc.simple_poll);
1085
fprintf(stderr, "%s exiting\n", argv[0]);
1088
/* Cleanup things */
1090
avahi_s_service_browser_free(sb);
1092
if (mc.server != NULL)
1093
avahi_server_free(mc.server);
1095
if (mc.simple_poll != NULL)
1096
avahi_simple_poll_free(mc.simple_poll);
1098
if (gnutls_initalized){
1099
gnutls_certificate_free_credentials(mc.cred);
1100
gnutls_global_deinit ();
1103
if(pgpme_initalized){
1104
gpgme_release(mc.ctx);
1107
/* Removes the temp directory used by GPGME */
1108
if(tempdir[0] != '\0'){
1110
struct dirent *direntry;
1111
d = opendir(tempdir);
1116
direntry = readdir(d);
1117
if(direntry == NULL){
1120
if (direntry->d_type == DT_REG){
1121
char *fullname = NULL;
1122
ret = asprintf(&fullname, "%s/%s", tempdir,
1128
ret = unlink(fullname);
1130
fprintf(stderr, "unlink(\"%s\"): %s",
1131
fullname, strerror(errno));
1137
ret = rmdir(tempdir);