812
1171
case AVAHI_BROWSER_ALL_FOR_NOW:
813
1172
case AVAHI_BROWSER_CACHE_EXHAUSTED:
815
fprintf(stderr, "No Mandos server found, still searching...\n");
1174
fprintf_plus(stderr, "No Mandos server found, still"
1181
/* Signal handler that stops main loop after SIGTERM */
1182
static void handle_sigterm(int sig){
1187
signal_received = sig;
1188
int old_errno = errno;
1189
/* set main loop to exit */
1190
if(simple_poll != NULL){
1191
avahi_simple_poll_quit(simple_poll);
1196
__attribute__((nonnull, warn_unused_result))
1197
bool get_flags(const char *ifname, struct ifreq *ifr){
1201
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1204
perror_plus("socket");
1208
strcpy(ifr->ifr_name, ifname);
1209
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1213
perror_plus("ioctl SIOCGIFFLAGS");
1221
__attribute__((nonnull, warn_unused_result))
1222
bool good_flags(const char *ifname, const struct ifreq *ifr){
1224
/* Reject the loopback device */
1225
if(ifr->ifr_flags & IFF_LOOPBACK){
1227
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1232
/* Accept point-to-point devices only if connect_to is specified */
1233
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1235
fprintf_plus(stderr, "Accepting point-to-point interface"
1236
" \"%s\"\n", ifname);
1240
/* Otherwise, reject non-broadcast-capable devices */
1241
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1243
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1244
" \"%s\"\n", ifname);
1248
/* Reject non-ARP interfaces (including dummy interfaces) */
1249
if(ifr->ifr_flags & IFF_NOARP){
1251
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1257
/* Accept this device */
1259
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1265
* This function determines if a directory entry in /sys/class/net
1266
* corresponds to an acceptable network device.
1267
* (This function is passed to scandir(3) as a filter function.)
1269
__attribute__((nonnull, warn_unused_result))
1270
int good_interface(const struct dirent *if_entry){
1271
if(if_entry->d_name[0] == '.'){
1276
if(not get_flags(if_entry->d_name, &ifr)){
1278
fprintf_plus(stderr, "Failed to get flags for interface "
1279
"\"%s\"\n", if_entry->d_name);
1284
if(not good_flags(if_entry->d_name, &ifr)){
1291
* This function determines if a network interface is up.
1293
__attribute__((nonnull, warn_unused_result))
1294
bool interface_is_up(const char *interface){
1296
if(not get_flags(interface, &ifr)){
1298
fprintf_plus(stderr, "Failed to get flags for interface "
1299
"\"%s\"\n", interface);
1304
return (bool)(ifr.ifr_flags & IFF_UP);
1308
* This function determines if a network interface is running
1310
__attribute__((nonnull, warn_unused_result))
1311
bool interface_is_running(const char *interface){
1313
if(not get_flags(interface, &ifr)){
1315
fprintf_plus(stderr, "Failed to get flags for interface "
1316
"\"%s\"\n", interface);
1321
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1324
__attribute__((nonnull, pure, warn_unused_result))
1325
int notdotentries(const struct dirent *direntry){
1326
/* Skip "." and ".." */
1327
if(direntry->d_name[0] == '.'
1328
and (direntry->d_name[1] == '\0'
1329
or (direntry->d_name[1] == '.'
1330
and direntry->d_name[2] == '\0'))){
1336
/* Is this directory entry a runnable program? */
1337
__attribute__((nonnull, warn_unused_result))
1338
int runnable_hook(const struct dirent *direntry){
1343
if((direntry->d_name)[0] == '\0'){
1348
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1349
"abcdefghijklmnopqrstuvwxyz"
1352
if((direntry->d_name)[sret] != '\0'){
1353
/* Contains non-allowed characters */
1355
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1361
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1364
perror_plus("Could not stat hook");
1368
if(not (S_ISREG(st.st_mode))){
1369
/* Not a regular file */
1371
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1376
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1377
/* Not executable */
1379
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1385
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1391
__attribute__((nonnull, warn_unused_result))
1392
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1393
mandos_context *mc){
1395
struct timespec now;
1396
struct timespec waited_time;
1397
intmax_t block_time;
1400
if(mc->current_server == NULL){
1402
fprintf_plus(stderr, "Wait until first server is found."
1405
ret = avahi_simple_poll_iterate(s, -1);
1408
fprintf_plus(stderr, "Check current_server if we should run"
1411
/* the current time */
1412
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1414
perror_plus("clock_gettime");
1417
/* Calculating in ms how long time between now and server
1418
who we visted longest time ago. Now - last seen. */
1419
waited_time.tv_sec = (now.tv_sec
1420
- mc->current_server->last_seen.tv_sec);
1421
waited_time.tv_nsec = (now.tv_nsec
1422
- mc->current_server->last_seen.tv_nsec);
1423
/* total time is 10s/10,000ms.
1424
Converting to s from ms by dividing by 1,000,
1425
and ns to ms by dividing by 1,000,000. */
1426
block_time = ((retry_interval
1427
- ((intmax_t)waited_time.tv_sec * 1000))
1428
- ((intmax_t)waited_time.tv_nsec / 1000000));
1431
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1435
if(block_time <= 0){
1436
ret = start_mandos_communication(mc->current_server->ip,
1437
mc->current_server->port,
1438
mc->current_server->if_index,
1439
mc->current_server->af, mc);
1441
avahi_simple_poll_quit(s);
1444
ret = clock_gettime(CLOCK_MONOTONIC,
1445
&mc->current_server->last_seen);
1447
perror_plus("clock_gettime");
1450
mc->current_server = mc->current_server->next;
1451
block_time = 0; /* Call avahi to find new Mandos
1452
servers, but don't block */
1455
ret = avahi_simple_poll_iterate(s, (int)block_time);
1458
if(ret > 0 or errno != EINTR){
1459
return (ret != 1) ? ret : 0;
1465
/* Set effective uid to 0, return errno */
1466
__attribute__((warn_unused_result))
1467
error_t raise_privileges(void){
1468
error_t old_errno = errno;
1469
error_t ret_errno = 0;
1470
if(seteuid(0) == -1){
1477
/* Set effective and real user ID to 0. Return errno. */
1478
__attribute__((warn_unused_result))
1479
error_t raise_privileges_permanently(void){
1480
error_t old_errno = errno;
1481
error_t ret_errno = raise_privileges();
1486
if(setuid(0) == -1){
1493
/* Set effective user ID to unprivileged saved user ID */
1494
__attribute__((warn_unused_result))
1495
error_t lower_privileges(void){
1496
error_t old_errno = errno;
1497
error_t ret_errno = 0;
1498
if(seteuid(uid) == -1){
1505
/* Lower privileges permanently */
1506
__attribute__((warn_unused_result))
1507
error_t lower_privileges_permanently(void){
1508
error_t old_errno = errno;
1509
error_t ret_errno = 0;
1510
if(setuid(uid) == -1){
1517
__attribute__((nonnull))
1518
void run_network_hooks(const char *mode, const char *interface,
1520
struct dirent **direntries = NULL;
1521
if(hookdir_fd == -1){
1522
hookdir_fd = open(hookdir, O_RDONLY);
1523
if(hookdir_fd == -1){
1524
if(errno == ENOENT){
1526
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1527
" found\n", hookdir);
1530
perror_plus("open");
1536
#if __GLIBC_PREREQ(2, 15)
1537
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1538
runnable_hook, alphasort);
1539
#else /* not __GLIBC_PREREQ(2, 15) */
1540
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1542
#endif /* not __GLIBC_PREREQ(2, 15) */
1543
#else /* not __GLIBC__ */
1544
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1546
#endif /* not __GLIBC__ */
1548
perror_plus("scandir");
1551
struct dirent *direntry;
1553
int devnull = open("/dev/null", O_RDONLY);
1554
for(int i = 0; i < numhooks; i++){
1555
direntry = direntries[i];
1557
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1560
pid_t hook_pid = fork();
1563
/* Raise privileges */
1564
errno = raise_privileges_permanently();
1566
perror_plus("Failed to raise privileges");
1573
perror_plus("setgid");
1576
/* Reset supplementary groups */
1578
ret = setgroups(0, NULL);
1580
perror_plus("setgroups");
1583
ret = dup2(devnull, STDIN_FILENO);
1585
perror_plus("dup2(devnull, STDIN_FILENO)");
1588
ret = close(devnull);
1590
perror_plus("close");
1593
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1595
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1598
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1600
perror_plus("setenv");
1603
ret = setenv("DEVICE", interface, 1);
1605
perror_plus("setenv");
1608
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1610
perror_plus("setenv");
1613
ret = setenv("MODE", mode, 1);
1615
perror_plus("setenv");
1619
ret = asprintf(&delaystring, "%f", (double)delay);
1621
perror_plus("asprintf");
1624
ret = setenv("DELAY", delaystring, 1);
1627
perror_plus("setenv");
1631
if(connect_to != NULL){
1632
ret = setenv("CONNECT", connect_to, 1);
1634
perror_plus("setenv");
1638
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1640
perror_plus("openat");
1641
_exit(EXIT_FAILURE);
1643
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1644
perror_plus("close");
1645
_exit(EXIT_FAILURE);
1647
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1649
perror_plus("fexecve");
1650
_exit(EXIT_FAILURE);
1654
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1655
perror_plus("waitpid");
1659
if(WIFEXITED(status)){
1660
if(WEXITSTATUS(status) != 0){
1661
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1662
" with status %d\n", direntry->d_name,
1663
WEXITSTATUS(status));
1667
} else if(WIFSIGNALED(status)){
1668
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1669
" signal %d\n", direntry->d_name,
1674
fprintf_plus(stderr, "Warning: network hook \"%s\""
1675
" crashed\n", direntry->d_name);
1681
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1687
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1688
perror_plus("close");
1695
__attribute__((nonnull, warn_unused_result))
1696
error_t bring_up_interface(const char *const interface,
1698
error_t old_errno = errno;
1700
struct ifreq network;
1701
unsigned int if_index = if_nametoindex(interface);
1703
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1713
if(not interface_is_up(interface)){
1714
error_t ret_errno = 0, ioctl_errno = 0;
1715
if(not get_flags(interface, &network)){
1717
fprintf_plus(stderr, "Failed to get flags for interface "
1718
"\"%s\"\n", interface);
1722
network.ifr_flags |= IFF_UP; /* set flag */
1724
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1727
perror_plus("socket");
1733
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1735
perror_plus("close");
1742
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1746
/* Raise privileges */
1747
ret_errno = raise_privileges();
1750
perror_plus("Failed to raise privileges");
1755
bool restore_loglevel = false;
1757
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1758
messages about the network interface to mess up the prompt */
1759
ret_linux = klogctl(8, NULL, 5);
1760
if(ret_linux == -1){
1761
perror_plus("klogctl");
1763
restore_loglevel = true;
1766
#endif /* __linux__ */
1767
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1768
ioctl_errno = errno;
1770
if(restore_loglevel){
1771
ret_linux = klogctl(7, NULL, 0);
1772
if(ret_linux == -1){
1773
perror_plus("klogctl");
1776
#endif /* __linux__ */
1778
/* If raise_privileges() succeeded above */
1780
/* Lower privileges */
1781
ret_errno = lower_privileges();
1784
perror_plus("Failed to lower privileges");
1788
/* Close the socket */
1789
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1791
perror_plus("close");
1794
if(ret_setflags == -1){
1795
errno = ioctl_errno;
1796
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1801
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1805
/* Sleep checking until interface is running.
1806
Check every 0.25s, up to total time of delay */
1807
for(int i=0; i < delay * 4; i++){
1808
if(interface_is_running(interface)){
1811
struct timespec sleeptime = { .tv_nsec = 250000000 };
1812
ret = nanosleep(&sleeptime, NULL);
1813
if(ret == -1 and errno != EINTR){
1814
perror_plus("nanosleep");
1822
__attribute__((nonnull, warn_unused_result))
1823
error_t take_down_interface(const char *const interface){
1824
error_t old_errno = errno;
1825
struct ifreq network;
1826
unsigned int if_index = if_nametoindex(interface);
1828
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1832
if(interface_is_up(interface)){
1833
error_t ret_errno = 0, ioctl_errno = 0;
1834
if(not get_flags(interface, &network) and debug){
1836
fprintf_plus(stderr, "Failed to get flags for interface "
1837
"\"%s\"\n", interface);
1841
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1843
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1846
perror_plus("socket");
1852
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1856
/* Raise privileges */
1857
ret_errno = raise_privileges();
1860
perror_plus("Failed to raise privileges");
1863
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1864
ioctl_errno = errno;
1866
/* If raise_privileges() succeeded above */
1868
/* Lower privileges */
1869
ret_errno = lower_privileges();
1872
perror_plus("Failed to lower privileges");
1876
/* Close the socket */
1877
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1879
perror_plus("close");
1882
if(ret_setflags == -1){
1883
errno = ioctl_errno;
1884
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1889
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
821
1897
int main(int argc, char *argv[]){
822
AvahiSServiceBrowser *sb = NULL;
827
int exitcode = EXIT_SUCCESS;
828
const char *interface = "eth0";
829
struct ifreq network;
833
char *connect_to = NULL;
834
char tempdir[] = "/tmp/mandosXXXXXX";
835
bool tempdir_created = false;
836
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
837
const char *seckey = PATHDIR "/" SECKEY;
838
const char *pubkey = PATHDIR "/" PUBKEY;
840
mandos_context mc = { .simple_poll = NULL, .server = NULL,
841
.dh_bits = 1024, .priority = "SECURE256"
842
":!CTYPE-X.509:+CTYPE-OPENPGP" };
843
bool gnutls_initialized = false;
844
bool gpgme_initialized = false;
847
struct argp_option options[] = {
848
{ .name = "debug", .key = 128,
849
.doc = "Debug mode", .group = 3 },
850
{ .name = "connect", .key = 'c',
851
.arg = "ADDRESS:PORT",
852
.doc = "Connect directly to a specific Mandos server",
854
{ .name = "interface", .key = 'i',
856
.doc = "Interface that will be used to search for Mandos"
859
{ .name = "seckey", .key = 's',
861
.doc = "OpenPGP secret key file base name",
863
{ .name = "pubkey", .key = 'p',
865
.doc = "OpenPGP public key file base name",
867
{ .name = "dh-bits", .key = 129,
869
.doc = "Bit length of the prime number used in the"
870
" Diffie-Hellman key exchange",
872
{ .name = "priority", .key = 130,
874
.doc = "GnuTLS priority string for the TLS handshake",
879
error_t parse_opt(int key, char *arg,
880
struct argp_state *state) {
882
case 128: /* --debug */
885
case 'c': /* --connect */
888
case 'i': /* --interface */
891
case 's': /* --seckey */
894
case 'p': /* --pubkey */
897
case 129: /* --dh-bits */
898
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
899
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
900
or arg[numchars] != '\0'){
901
fprintf(stderr, "Bad number of DH bits\n");
904
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
906
case 130: /* --priority */
914
return ARGP_ERR_UNKNOWN;
919
struct argp argp = { .options = options, .parser = parse_opt,
921
.doc = "Mandos client -- Get and decrypt"
922
" passwords from a Mandos server" };
923
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
924
if(ret == ARGP_ERR_UNKNOWN){
925
fprintf(stderr, "Unknown error while parsing arguments\n");
926
exitcode = EXIT_FAILURE;
931
/* If the interface is down, bring it up */
933
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
936
exitcode = EXIT_FAILURE;
939
strcpy(network.ifr_name, interface);
940
ret = ioctl(sd, SIOCGIFFLAGS, &network);
942
perror("ioctl SIOCGIFFLAGS");
943
exitcode = EXIT_FAILURE;
946
if((network.ifr_flags & IFF_UP) == 0){
947
network.ifr_flags |= IFF_UP;
948
ret = ioctl(sd, SIOCSIFFLAGS, &network);
950
perror("ioctl SIOCSIFFLAGS");
951
exitcode = EXIT_FAILURE;
955
ret = (int)TEMP_FAILURE_RETRY(close(sd));
974
ret = init_gnutls_global(&mc, pubkey, seckey);
976
fprintf(stderr, "init_gnutls_global failed\n");
977
exitcode = EXIT_FAILURE;
980
gnutls_initialized = true;
983
if(mkdtemp(tempdir) == NULL){
987
tempdir_created = true;
989
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
990
fprintf(stderr, "init_gpgme failed\n");
991
exitcode = EXIT_FAILURE;
994
gpgme_initialized = true;
997
if_index = (AvahiIfIndex) if_nametoindex(interface);
999
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1000
exitcode = EXIT_FAILURE;
1004
if(connect_to != NULL){
1005
/* Connect directly, do not use Zeroconf */
1006
/* (Mainly meant for debugging) */
1007
char *address = strrchr(connect_to, ':');
1008
if(address == NULL){
1009
fprintf(stderr, "No colon in address\n");
1010
exitcode = EXIT_FAILURE;
1014
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1015
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1016
or address[numchars+1] != '\0'){
1017
fprintf(stderr, "Bad port number\n");
1018
exitcode = EXIT_FAILURE;
1021
port = (uint16_t)tmpmax;
1023
address = connect_to;
1024
ret = start_mandos_communication(address, port, if_index, &mc);
1026
exitcode = EXIT_FAILURE;
1028
exitcode = EXIT_SUCCESS;
1034
avahi_set_log_function(empty_log);
1037
/* Initialize the pseudo-RNG for Avahi */
1038
srand((unsigned int) time(NULL));
1040
/* Allocate main Avahi loop object */
1041
mc.simple_poll = avahi_simple_poll_new();
1042
if(mc.simple_poll == NULL) {
1043
fprintf(stderr, "Avahi: Failed to create simple poll"
1045
exitcode = EXIT_FAILURE;
1050
AvahiServerConfig config;
1051
/* Do not publish any local Zeroconf records */
1052
avahi_server_config_init(&config);
1053
config.publish_hinfo = 0;
1054
config.publish_addresses = 0;
1055
config.publish_workstation = 0;
1056
config.publish_domain = 0;
1058
/* Allocate a new server */
1059
mc.server = avahi_server_new(avahi_simple_poll_get
1060
(mc.simple_poll), &config, NULL,
1063
/* Free the Avahi configuration data */
1064
avahi_server_config_free(&config);
1067
/* Check if creating the Avahi server object succeeded */
1068
if(mc.server == NULL) {
1069
fprintf(stderr, "Failed to create Avahi server: %s\n",
1070
avahi_strerror(error));
1071
exitcode = EXIT_FAILURE;
1075
/* Create the Avahi service browser */
1076
sb = avahi_s_service_browser_new(mc.server, if_index,
1078
"_mandos._tcp", NULL, 0,
1079
browse_callback, &mc);
1081
fprintf(stderr, "Failed to create service browser: %s\n",
1082
avahi_strerror(avahi_server_errno(mc.server)));
1083
exitcode = EXIT_FAILURE;
1087
/* Run the main loop */
1898
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1899
.priority = "SECURE256:!CTYPE-X.509:"
1900
"+CTYPE-OPENPGP", .current_server = NULL,
1901
.interfaces = NULL, .interfaces_size = 0 };
1902
AvahiSServiceBrowser *sb = NULL;
1907
int exitcode = EXIT_SUCCESS;
1908
char *interfaces_to_take_down = NULL;
1909
size_t interfaces_to_take_down_size = 0;
1910
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1911
char old_tempdir[] = "/tmp/mandosXXXXXX";
1912
char *tempdir = NULL;
1913
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1914
const char *seckey = PATHDIR "/" SECKEY;
1915
const char *pubkey = PATHDIR "/" PUBKEY;
1916
char *interfaces_hooks = NULL;
1918
bool gnutls_initialized = false;
1919
bool gpgme_initialized = false;
1921
double retry_interval = 10; /* 10s between trying a server and
1922
retrying the same server again */
1924
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1925
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1930
/* Lower any group privileges we might have, just to be safe */
1934
perror_plus("setgid");
1937
/* Lower user privileges (temporarily) */
1941
perror_plus("seteuid");
1949
struct argp_option options[] = {
1950
{ .name = "debug", .key = 128,
1951
.doc = "Debug mode", .group = 3 },
1952
{ .name = "connect", .key = 'c',
1953
.arg = "ADDRESS:PORT",
1954
.doc = "Connect directly to a specific Mandos server",
1956
{ .name = "interface", .key = 'i',
1958
.doc = "Network interface that will be used to search for"
1961
{ .name = "seckey", .key = 's',
1963
.doc = "OpenPGP secret key file base name",
1965
{ .name = "pubkey", .key = 'p',
1967
.doc = "OpenPGP public key file base name",
1969
{ .name = "dh-bits", .key = 129,
1971
.doc = "Bit length of the prime number used in the"
1972
" Diffie-Hellman key exchange",
1974
{ .name = "priority", .key = 130,
1976
.doc = "GnuTLS priority string for the TLS handshake",
1978
{ .name = "delay", .key = 131,
1980
.doc = "Maximum delay to wait for interface startup",
1982
{ .name = "retry", .key = 132,
1984
.doc = "Retry interval used when denied by the Mandos server",
1986
{ .name = "network-hook-dir", .key = 133,
1988
.doc = "Directory where network hooks are located",
1991
* These reproduce what we would get without ARGP_NO_HELP
1993
{ .name = "help", .key = '?',
1994
.doc = "Give this help list", .group = -1 },
1995
{ .name = "usage", .key = -3,
1996
.doc = "Give a short usage message", .group = -1 },
1997
{ .name = "version", .key = 'V',
1998
.doc = "Print program version", .group = -1 },
2002
error_t parse_opt(int key, char *arg,
2003
struct argp_state *state){
2006
case 128: /* --debug */
2009
case 'c': /* --connect */
2012
case 'i': /* --interface */
2013
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2016
argp_error(state, "%s", strerror(ret_errno));
2019
case 's': /* --seckey */
2022
case 'p': /* --pubkey */
2025
case 129: /* --dh-bits */
2027
tmpmax = strtoimax(arg, &tmp, 10);
2028
if(errno != 0 or tmp == arg or *tmp != '\0'
2029
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2030
argp_error(state, "Bad number of DH bits");
2032
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2034
case 130: /* --priority */
2037
case 131: /* --delay */
2039
delay = strtof(arg, &tmp);
2040
if(errno != 0 or tmp == arg or *tmp != '\0'){
2041
argp_error(state, "Bad delay");
2043
case 132: /* --retry */
2045
retry_interval = strtod(arg, &tmp);
2046
if(errno != 0 or tmp == arg or *tmp != '\0'
2047
or (retry_interval * 1000) > INT_MAX
2048
or retry_interval < 0){
2049
argp_error(state, "Bad retry interval");
2052
case 133: /* --network-hook-dir */
2056
* These reproduce what we would get without ARGP_NO_HELP
2058
case '?': /* --help */
2059
argp_state_help(state, state->out_stream,
2060
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2061
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2062
case -3: /* --usage */
2063
argp_state_help(state, state->out_stream,
2064
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2065
case 'V': /* --version */
2066
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2067
exit(argp_err_exit_status);
2070
return ARGP_ERR_UNKNOWN;
2075
struct argp argp = { .options = options, .parser = parse_opt,
2077
.doc = "Mandos client -- Get and decrypt"
2078
" passwords from a Mandos server" };
2079
ret = argp_parse(&argp, argc, argv,
2080
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2087
perror_plus("argp_parse");
2088
exitcode = EX_OSERR;
2091
exitcode = EX_USAGE;
2097
/* Work around Debian bug #633582:
2098
<http://bugs.debian.org/633582> */
2100
/* Re-raise privileges */
2101
ret_errno = raise_privileges();
2104
perror_plus("Failed to raise privileges");
2108
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2109
int seckey_fd = open(seckey, O_RDONLY);
2110
if(seckey_fd == -1){
2111
perror_plus("open");
2113
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2115
perror_plus("fstat");
2117
if(S_ISREG(st.st_mode)
2118
and st.st_uid == 0 and st.st_gid == 0){
2119
ret = fchown(seckey_fd, uid, gid);
2121
perror_plus("fchown");
2125
TEMP_FAILURE_RETRY(close(seckey_fd));
2129
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2130
int pubkey_fd = open(pubkey, O_RDONLY);
2131
if(pubkey_fd == -1){
2132
perror_plus("open");
2134
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2136
perror_plus("fstat");
2138
if(S_ISREG(st.st_mode)
2139
and st.st_uid == 0 and st.st_gid == 0){
2140
ret = fchown(pubkey_fd, uid, gid);
2142
perror_plus("fchown");
2146
TEMP_FAILURE_RETRY(close(pubkey_fd));
2150
/* Lower privileges */
2151
ret_errno = lower_privileges();
2154
perror_plus("Failed to lower privileges");
2159
/* Remove invalid interface names (except "none") */
2161
char *interface = NULL;
2162
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2164
if(strcmp(interface, "none") != 0
2165
and if_nametoindex(interface) == 0){
2166
if(interface[0] != '\0'){
2167
fprintf_plus(stderr, "Not using nonexisting interface"
2168
" \"%s\"\n", interface);
2170
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2176
/* Run network hooks */
2178
if(mc.interfaces != NULL){
2179
interfaces_hooks = malloc(mc.interfaces_size);
2180
if(interfaces_hooks == NULL){
2181
perror_plus("malloc");
2184
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2185
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2187
run_network_hooks("start", interfaces_hooks != NULL ?
2188
interfaces_hooks : "", delay);
2192
avahi_set_log_function(empty_log);
2195
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2196
from the signal handler */
2197
/* Initialize the pseudo-RNG for Avahi */
2198
srand((unsigned int) time(NULL));
2199
simple_poll = avahi_simple_poll_new();
2200
if(simple_poll == NULL){
2201
fprintf_plus(stderr,
2202
"Avahi: Failed to create simple poll object.\n");
2203
exitcode = EX_UNAVAILABLE;
2207
sigemptyset(&sigterm_action.sa_mask);
2208
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2210
perror_plus("sigaddset");
2211
exitcode = EX_OSERR;
2214
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2216
perror_plus("sigaddset");
2217
exitcode = EX_OSERR;
2220
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2222
perror_plus("sigaddset");
2223
exitcode = EX_OSERR;
2226
/* Need to check if the handler is SIG_IGN before handling:
2227
| [[info:libc:Initial Signal Actions]] |
2228
| [[info:libc:Basic Signal Handling]] |
2230
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2232
perror_plus("sigaction");
2235
if(old_sigterm_action.sa_handler != SIG_IGN){
2236
ret = sigaction(SIGINT, &sigterm_action, NULL);
2238
perror_plus("sigaction");
2239
exitcode = EX_OSERR;
2243
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2245
perror_plus("sigaction");
2248
if(old_sigterm_action.sa_handler != SIG_IGN){
2249
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2251
perror_plus("sigaction");
2252
exitcode = EX_OSERR;
2256
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2258
perror_plus("sigaction");
2261
if(old_sigterm_action.sa_handler != SIG_IGN){
2262
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2264
perror_plus("sigaction");
2265
exitcode = EX_OSERR;
2270
/* If no interfaces were specified, make a list */
2271
if(mc.interfaces == NULL){
2272
struct dirent **direntries = NULL;
2273
/* Look for any good interfaces */
2274
ret = scandir(sys_class_net, &direntries, good_interface,
2277
/* Add all found interfaces to interfaces list */
2278
for(int i = 0; i < ret; ++i){
2279
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2280
direntries[i]->d_name);
2283
perror_plus("argz_add");
2284
free(direntries[i]);
2288
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2289
direntries[i]->d_name);
2291
free(direntries[i]);
2298
fprintf_plus(stderr, "Could not find a network interface\n");
2299
exitcode = EXIT_FAILURE;
2304
/* Bring up interfaces which are down, and remove any "none"s */
2306
char *interface = NULL;
2307
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2309
/* If interface name is "none", stop bringing up interfaces.
2310
Also remove all instances of "none" from the list */
2311
if(strcmp(interface, "none") == 0){
2312
argz_delete(&mc.interfaces, &mc.interfaces_size,
2315
while((interface = argz_next(mc.interfaces,
2316
mc.interfaces_size, interface))){
2317
if(strcmp(interface, "none") == 0){
2318
argz_delete(&mc.interfaces, &mc.interfaces_size,
2325
bool interface_was_up = interface_is_up(interface);
2326
errno = bring_up_interface(interface, delay);
2327
if(not interface_was_up){
2329
perror_plus("Failed to bring up interface");
2331
errno = argz_add(&interfaces_to_take_down,
2332
&interfaces_to_take_down_size,
2335
perror_plus("argz_add");
2340
if(debug and (interfaces_to_take_down == NULL)){
2341
fprintf_plus(stderr, "No interfaces were brought up\n");
2345
/* If we only got one interface, explicitly use only that one */
2346
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
1090
fprintf(stderr, "Starting Avahi loop search\n");
1093
avahi_simple_poll_loop(mc.simple_poll);
2348
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2351
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2358
ret = init_gnutls_global(pubkey, seckey, &mc);
2360
fprintf_plus(stderr, "init_gnutls_global failed\n");
2361
exitcode = EX_UNAVAILABLE;
2364
gnutls_initialized = true;
2371
/* Try /run/tmp before /tmp */
2372
tempdir = mkdtemp(run_tempdir);
2373
if(tempdir == NULL and errno == ENOENT){
2375
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2376
run_tempdir, old_tempdir);
2378
tempdir = mkdtemp(old_tempdir);
2380
if(tempdir == NULL){
2381
perror_plus("mkdtemp");
2389
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2390
fprintf_plus(stderr, "init_gpgme failed\n");
2391
exitcode = EX_UNAVAILABLE;
2394
gpgme_initialized = true;
2401
if(connect_to != NULL){
2402
/* Connect directly, do not use Zeroconf */
2403
/* (Mainly meant for debugging) */
2404
char *address = strrchr(connect_to, ':');
2406
if(address == NULL){
2407
fprintf_plus(stderr, "No colon in address\n");
2408
exitcode = EX_USAGE;
2418
tmpmax = strtoimax(address+1, &tmp, 10);
2419
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2420
or tmpmax != (in_port_t)tmpmax){
2421
fprintf_plus(stderr, "Bad port number\n");
2422
exitcode = EX_USAGE;
2430
port = (in_port_t)tmpmax;
2432
/* Colon in address indicates IPv6 */
2434
if(strchr(connect_to, ':') != NULL){
2436
/* Accept [] around IPv6 address - see RFC 5952 */
2437
if(connect_to[0] == '[' and address[-1] == ']')
2445
address = connect_to;
2451
while(not quit_now){
2452
ret = start_mandos_communication(address, port, if_index, af,
2454
if(quit_now or ret == 0){
2458
fprintf_plus(stderr, "Retrying in %d seconds\n",
2459
(int)retry_interval);
2461
sleep((unsigned int)retry_interval);
2465
exitcode = EXIT_SUCCESS;
2476
AvahiServerConfig config;
2477
/* Do not publish any local Zeroconf records */
2478
avahi_server_config_init(&config);
2479
config.publish_hinfo = 0;
2480
config.publish_addresses = 0;
2481
config.publish_workstation = 0;
2482
config.publish_domain = 0;
2484
/* Allocate a new server */
2485
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2486
&config, NULL, NULL, &ret_errno);
2488
/* Free the Avahi configuration data */
2489
avahi_server_config_free(&config);
2492
/* Check if creating the Avahi server object succeeded */
2493
if(mc.server == NULL){
2494
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2495
avahi_strerror(ret_errno));
2496
exitcode = EX_UNAVAILABLE;
2504
/* Create the Avahi service browser */
2505
sb = avahi_s_service_browser_new(mc.server, if_index,
2506
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2507
NULL, 0, browse_callback,
2510
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2511
avahi_strerror(avahi_server_errno(mc.server)));
2512
exitcode = EX_UNAVAILABLE;
2520
/* Run the main loop */
2523
fprintf_plus(stderr, "Starting Avahi loop search\n");
2526
ret = avahi_loop_with_timeout(simple_poll,
2527
(int)(retry_interval * 1000), &mc);
2529
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2530
(ret == 0) ? "successfully" : "with error");
1098
fprintf(stderr, "%s exiting\n", argv[0]);
1101
/* Cleanup things */
1103
avahi_s_service_browser_free(sb);
1105
if(mc.server != NULL)
1106
avahi_server_free(mc.server);
1108
if(mc.simple_poll != NULL)
1109
avahi_simple_poll_free(mc.simple_poll);
1111
if(gnutls_initialized){
1112
gnutls_certificate_free_credentials(mc.cred);
1113
gnutls_global_deinit();
1114
gnutls_dh_params_deinit(mc.dh_params);
1117
if(gpgme_initialized){
1118
gpgme_release(mc.ctx);
1121
/* Removes the temp directory used by GPGME */
1122
if(tempdir_created){
1124
struct dirent *direntry;
1125
d = opendir(tempdir);
1127
if(errno != ENOENT){
1132
direntry = readdir(d);
1133
if(direntry == NULL){
1136
/* Skip "." and ".." */
1137
if(direntry->d_name[0] == '.'
1138
and (direntry->d_name[1] == '\0'
1139
or (direntry->d_name[1] == '.'
1140
and direntry->d_name[2] == '\0'))){
1143
char *fullname = NULL;
1144
ret = asprintf(&fullname, "%s/%s", tempdir,
1150
ret = remove(fullname);
2536
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2539
/* Cleanup things */
2540
free(mc.interfaces);
2543
avahi_s_service_browser_free(sb);
2545
if(mc.server != NULL)
2546
avahi_server_free(mc.server);
2548
if(simple_poll != NULL)
2549
avahi_simple_poll_free(simple_poll);
2551
if(gnutls_initialized){
2552
gnutls_certificate_free_credentials(mc.cred);
2553
gnutls_global_deinit();
2554
gnutls_dh_params_deinit(mc.dh_params);
2557
if(gpgme_initialized){
2558
gpgme_release(mc.ctx);
2561
/* Cleans up the circular linked list of Mandos servers the client
2563
if(mc.current_server != NULL){
2564
mc.current_server->prev->next = NULL;
2565
while(mc.current_server != NULL){
2566
server *next = mc.current_server->next;
2568
#pragma GCC diagnostic push
2569
#pragma GCC diagnostic ignored "-Wcast-qual"
2571
free((char *)(mc.current_server->ip));
2573
#pragma GCC diagnostic pop
2575
free(mc.current_server);
2576
mc.current_server = next;
2580
/* Re-raise privileges */
2582
ret_errno = raise_privileges();
2585
perror_plus("Failed to raise privileges");
2588
/* Run network hooks */
2589
run_network_hooks("stop", interfaces_hooks != NULL ?
2590
interfaces_hooks : "", delay);
2592
/* Take down the network interfaces which were brought up */
2594
char *interface = NULL;
2595
while((interface=argz_next(interfaces_to_take_down,
2596
interfaces_to_take_down_size,
2598
ret_errno = take_down_interface(interface);
2601
perror_plus("Failed to take down interface");
2604
if(debug and (interfaces_to_take_down == NULL)){
2605
fprintf_plus(stderr, "No interfaces needed to be taken"
2611
ret_errno = lower_privileges_permanently();
2614
perror_plus("Failed to lower privileges permanently");
2618
free(interfaces_to_take_down);
2619
free(interfaces_hooks);
2621
/* Removes the GPGME temp directory and all files inside */
2622
if(tempdir != NULL){
2623
struct dirent **direntries = NULL;
2624
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2626
if(tempdir_fd == -1){
2627
perror_plus("open");
2630
#if __GLIBC_PREREQ(2, 15)
2631
int numentries = scandirat(tempdir_fd, ".", &direntries,
2632
notdotentries, alphasort);
2633
#else /* not __GLIBC_PREREQ(2, 15) */
2634
int numentries = scandir(tempdir, &direntries, notdotentries,
2636
#endif /* not __GLIBC_PREREQ(2, 15) */
2637
#else /* not __GLIBC__ */
2638
int numentries = scandir(tempdir, &direntries, notdotentries,
2640
#endif /* not __GLIBC__ */
2641
if(numentries >= 0){
2642
for(int i = 0; i < numentries; i++){
2643
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
1152
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2645
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2646
" \"%s\", 0): %s\n", tempdir,
2647
direntries[i]->d_name, strerror(errno));
1159
ret = rmdir(tempdir);
1160
if(ret == -1 and errno != ENOENT){
2649
free(direntries[i]);
2652
/* need to clean even if 0 because man page doesn't specify */
2654
if(numentries == -1){
2655
perror_plus("scandir");
2657
ret = rmdir(tempdir);
2658
if(ret == -1 and errno != ENOENT){
2659
perror_plus("rmdir");
2662
TEMP_FAILURE_RETRY(close(tempdir_fd));
2667
sigemptyset(&old_sigterm_action.sa_mask);
2668
old_sigterm_action.sa_handler = SIG_DFL;
2669
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2670
&old_sigterm_action,
2673
perror_plus("sigaction");
2676
ret = raise(signal_received);
2677
} while(ret != 0 and errno == EINTR);
2679
perror_plus("raise");
2682
TEMP_FAILURE_RETRY(pause());