811
1163
case AVAHI_BROWSER_ALL_FOR_NOW:
812
1164
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
fprintf(stderr, "No Mandos server found, still searching...\n");
1166
fprintf_plus(stderr, "No Mandos server found, still"
1173
/* Signal handler that stops main loop after SIGTERM */
1174
static void handle_sigterm(int sig){
1179
signal_received = sig;
1180
int old_errno = errno;
1181
/* set main loop to exit */
1182
if(simple_poll != NULL){
1183
avahi_simple_poll_quit(simple_poll);
1188
__attribute__((nonnull, warn_unused_result))
1189
bool get_flags(const char *ifname, struct ifreq *ifr){
1193
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1196
perror_plus("socket");
1200
strcpy(ifr->ifr_name, ifname);
1201
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1205
perror_plus("ioctl SIOCGIFFLAGS");
1213
__attribute__((nonnull, warn_unused_result))
1214
bool good_flags(const char *ifname, const struct ifreq *ifr){
1216
/* Reject the loopback device */
1217
if(ifr->ifr_flags & IFF_LOOPBACK){
1219
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1224
/* Accept point-to-point devices only if connect_to is specified */
1225
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1227
fprintf_plus(stderr, "Accepting point-to-point interface"
1228
" \"%s\"\n", ifname);
1232
/* Otherwise, reject non-broadcast-capable devices */
1233
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1235
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1236
" \"%s\"\n", ifname);
1240
/* Reject non-ARP interfaces (including dummy interfaces) */
1241
if(ifr->ifr_flags & IFF_NOARP){
1243
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1249
/* Accept this device */
1251
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1257
* This function determines if a directory entry in /sys/class/net
1258
* corresponds to an acceptable network device.
1259
* (This function is passed to scandir(3) as a filter function.)
1261
__attribute__((nonnull, warn_unused_result))
1262
int good_interface(const struct dirent *if_entry){
1263
if(if_entry->d_name[0] == '.'){
1268
if(not get_flags(if_entry->d_name, &ifr)){
1270
fprintf_plus(stderr, "Failed to get flags for interface "
1271
"\"%s\"\n", if_entry->d_name);
1276
if(not good_flags(if_entry->d_name, &ifr)){
1283
* This function determines if a network interface is up.
1285
__attribute__((nonnull, warn_unused_result))
1286
bool interface_is_up(const char *interface){
1288
if(not get_flags(interface, &ifr)){
1290
fprintf_plus(stderr, "Failed to get flags for interface "
1291
"\"%s\"\n", interface);
1296
return (bool)(ifr.ifr_flags & IFF_UP);
1300
* This function determines if a network interface is running
1302
__attribute__((nonnull, warn_unused_result))
1303
bool interface_is_running(const char *interface){
1305
if(not get_flags(interface, &ifr)){
1307
fprintf_plus(stderr, "Failed to get flags for interface "
1308
"\"%s\"\n", interface);
1313
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1316
__attribute__((nonnull, pure, warn_unused_result))
1317
int notdotentries(const struct dirent *direntry){
1318
/* Skip "." and ".." */
1319
if(direntry->d_name[0] == '.'
1320
and (direntry->d_name[1] == '\0'
1321
or (direntry->d_name[1] == '.'
1322
and direntry->d_name[2] == '\0'))){
1328
/* Is this directory entry a runnable program? */
1329
__attribute__((nonnull, warn_unused_result))
1330
int runnable_hook(const struct dirent *direntry){
1335
if((direntry->d_name)[0] == '\0'){
1340
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1341
"abcdefghijklmnopqrstuvwxyz"
1344
if((direntry->d_name)[sret] != '\0'){
1345
/* Contains non-allowed characters */
1347
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1353
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1356
perror_plus("Could not stat hook");
1360
if(not (S_ISREG(st.st_mode))){
1361
/* Not a regular file */
1363
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1368
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1369
/* Not executable */
1371
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1377
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1383
__attribute__((nonnull, warn_unused_result))
1384
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1385
mandos_context *mc){
1387
struct timespec now;
1388
struct timespec waited_time;
1389
intmax_t block_time;
1392
if(mc->current_server == NULL){
1394
fprintf_plus(stderr, "Wait until first server is found."
1397
ret = avahi_simple_poll_iterate(s, -1);
1400
fprintf_plus(stderr, "Check current_server if we should run"
1403
/* the current time */
1404
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1406
perror_plus("clock_gettime");
1409
/* Calculating in ms how long time between now and server
1410
who we visted longest time ago. Now - last seen. */
1411
waited_time.tv_sec = (now.tv_sec
1412
- mc->current_server->last_seen.tv_sec);
1413
waited_time.tv_nsec = (now.tv_nsec
1414
- mc->current_server->last_seen.tv_nsec);
1415
/* total time is 10s/10,000ms.
1416
Converting to s from ms by dividing by 1,000,
1417
and ns to ms by dividing by 1,000,000. */
1418
block_time = ((retry_interval
1419
- ((intmax_t)waited_time.tv_sec * 1000))
1420
- ((intmax_t)waited_time.tv_nsec / 1000000));
1423
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1427
if(block_time <= 0){
1428
ret = start_mandos_communication(mc->current_server->ip,
1429
mc->current_server->port,
1430
mc->current_server->if_index,
1431
mc->current_server->af, mc);
1433
avahi_simple_poll_quit(s);
1436
ret = clock_gettime(CLOCK_MONOTONIC,
1437
&mc->current_server->last_seen);
1439
perror_plus("clock_gettime");
1442
mc->current_server = mc->current_server->next;
1443
block_time = 0; /* Call avahi to find new Mandos
1444
servers, but don't block */
1447
ret = avahi_simple_poll_iterate(s, (int)block_time);
1450
if(ret > 0 or errno != EINTR){
1451
return (ret != 1) ? ret : 0;
1457
/* Set effective uid to 0, return errno */
1458
__attribute__((warn_unused_result))
1459
error_t raise_privileges(void){
1460
error_t old_errno = errno;
1461
error_t ret_errno = 0;
1462
if(seteuid(0) == -1){
1469
/* Set effective and real user ID to 0. Return errno. */
1470
__attribute__((warn_unused_result))
1471
error_t raise_privileges_permanently(void){
1472
error_t old_errno = errno;
1473
error_t ret_errno = raise_privileges();
1478
if(setuid(0) == -1){
1485
/* Set effective user ID to unprivileged saved user ID */
1486
__attribute__((warn_unused_result))
1487
error_t lower_privileges(void){
1488
error_t old_errno = errno;
1489
error_t ret_errno = 0;
1490
if(seteuid(uid) == -1){
1497
/* Lower privileges permanently */
1498
__attribute__((warn_unused_result))
1499
error_t lower_privileges_permanently(void){
1500
error_t old_errno = errno;
1501
error_t ret_errno = 0;
1502
if(setuid(uid) == -1){
1509
__attribute__((nonnull))
1510
void run_network_hooks(const char *mode, const char *interface,
1512
struct dirent **direntries = NULL;
1513
if(hookdir_fd == -1){
1514
hookdir_fd = open(hookdir, O_RDONLY);
1515
if(hookdir_fd == -1){
1516
if(errno == ENOENT){
1518
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1519
" found\n", hookdir);
1522
perror_plus("open");
1528
#if __GLIBC_PREREQ(2, 15)
1529
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1530
runnable_hook, alphasort);
1531
#else /* not __GLIBC_PREREQ(2, 15) */
1532
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1534
#endif /* not __GLIBC_PREREQ(2, 15) */
1535
#else /* not __GLIBC__ */
1536
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1538
#endif /* not __GLIBC__ */
1540
perror_plus("scandir");
1543
struct dirent *direntry;
1545
int devnull = open("/dev/null", O_RDONLY);
1546
for(int i = 0; i < numhooks; i++){
1547
direntry = direntries[i];
1549
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1552
pid_t hook_pid = fork();
1555
/* Raise privileges */
1556
errno = raise_privileges_permanently();
1558
perror_plus("Failed to raise privileges");
1565
perror_plus("setgid");
1568
/* Reset supplementary groups */
1570
ret = setgroups(0, NULL);
1572
perror_plus("setgroups");
1575
ret = dup2(devnull, STDIN_FILENO);
1577
perror_plus("dup2(devnull, STDIN_FILENO)");
1580
ret = close(devnull);
1582
perror_plus("close");
1585
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1587
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1590
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1592
perror_plus("setenv");
1595
ret = setenv("DEVICE", interface, 1);
1597
perror_plus("setenv");
1600
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1602
perror_plus("setenv");
1605
ret = setenv("MODE", mode, 1);
1607
perror_plus("setenv");
1611
ret = asprintf(&delaystring, "%f", (double)delay);
1613
perror_plus("asprintf");
1616
ret = setenv("DELAY", delaystring, 1);
1619
perror_plus("setenv");
1623
if(connect_to != NULL){
1624
ret = setenv("CONNECT", connect_to, 1);
1626
perror_plus("setenv");
1630
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1632
perror_plus("openat");
1633
_exit(EXIT_FAILURE);
1635
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1636
perror_plus("close");
1637
_exit(EXIT_FAILURE);
1639
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1641
perror_plus("fexecve");
1642
_exit(EXIT_FAILURE);
1646
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1647
perror_plus("waitpid");
1650
if(WIFEXITED(status)){
1651
if(WEXITSTATUS(status) != 0){
1652
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1653
" with status %d\n", direntry->d_name,
1654
WEXITSTATUS(status));
1657
} else if(WIFSIGNALED(status)){
1658
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1659
" signal %d\n", direntry->d_name,
1663
fprintf_plus(stderr, "Warning: network hook \"%s\""
1664
" crashed\n", direntry->d_name);
1669
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1674
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1675
perror_plus("close");
1682
__attribute__((nonnull, warn_unused_result))
1683
error_t bring_up_interface(const char *const interface,
1685
error_t old_errno = errno;
1687
struct ifreq network;
1688
unsigned int if_index = if_nametoindex(interface);
1690
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1700
if(not interface_is_up(interface)){
1701
error_t ret_errno = 0, ioctl_errno = 0;
1702
if(not get_flags(interface, &network)){
1704
fprintf_plus(stderr, "Failed to get flags for interface "
1705
"\"%s\"\n", interface);
1709
network.ifr_flags |= IFF_UP; /* set flag */
1711
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1714
perror_plus("socket");
1720
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1722
perror_plus("close");
1729
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1733
/* Raise privileges */
1734
ret_errno = raise_privileges();
1737
perror_plus("Failed to raise privileges");
1742
bool restore_loglevel = false;
1744
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1745
messages about the network interface to mess up the prompt */
1746
ret_linux = klogctl(8, NULL, 5);
1747
if(ret_linux == -1){
1748
perror_plus("klogctl");
1750
restore_loglevel = true;
1753
#endif /* __linux__ */
1754
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1755
ioctl_errno = errno;
1757
if(restore_loglevel){
1758
ret_linux = klogctl(7, NULL, 0);
1759
if(ret_linux == -1){
1760
perror_plus("klogctl");
1763
#endif /* __linux__ */
1765
/* If raise_privileges() succeeded above */
1767
/* Lower privileges */
1768
ret_errno = lower_privileges();
1771
perror_plus("Failed to lower privileges");
1775
/* Close the socket */
1776
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1778
perror_plus("close");
1781
if(ret_setflags == -1){
1782
errno = ioctl_errno;
1783
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1788
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1792
/* Sleep checking until interface is running.
1793
Check every 0.25s, up to total time of delay */
1794
for(int i=0; i < delay * 4; i++){
1795
if(interface_is_running(interface)){
1798
struct timespec sleeptime = { .tv_nsec = 250000000 };
1799
ret = nanosleep(&sleeptime, NULL);
1800
if(ret == -1 and errno != EINTR){
1801
perror_plus("nanosleep");
1809
__attribute__((nonnull, warn_unused_result))
1810
error_t take_down_interface(const char *const interface){
1811
error_t old_errno = errno;
1812
struct ifreq network;
1813
unsigned int if_index = if_nametoindex(interface);
1815
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1819
if(interface_is_up(interface)){
1820
error_t ret_errno = 0, ioctl_errno = 0;
1821
if(not get_flags(interface, &network) and debug){
1823
fprintf_plus(stderr, "Failed to get flags for interface "
1824
"\"%s\"\n", interface);
1828
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1830
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1833
perror_plus("socket");
1839
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1843
/* Raise privileges */
1844
ret_errno = raise_privileges();
1847
perror_plus("Failed to raise privileges");
1850
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1851
ioctl_errno = errno;
1853
/* If raise_privileges() succeeded above */
1855
/* Lower privileges */
1856
ret_errno = lower_privileges();
1859
perror_plus("Failed to lower privileges");
1863
/* Close the socket */
1864
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1866
perror_plus("close");
1869
if(ret_setflags == -1){
1870
errno = ioctl_errno;
1871
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1876
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
820
1884
int main(int argc, char *argv[]){
821
AvahiSServiceBrowser *sb = NULL;
826
int exitcode = EXIT_SUCCESS;
827
const char *interface = "eth0";
828
struct ifreq network;
832
char *connect_to = NULL;
833
char tempdir[] = "/tmp/mandosXXXXXX";
834
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
835
const char *seckey = PATHDIR "/" SECKEY;
836
const char *pubkey = PATHDIR "/" PUBKEY;
838
mandos_context mc = { .simple_poll = NULL, .server = NULL,
839
.dh_bits = 1024, .priority = "SECURE256"
840
":!CTYPE-X.509:+CTYPE-OPENPGP" };
841
bool gnutls_initialized = false;
842
bool gpgme_initialized = false;
845
struct argp_option options[] = {
846
{ .name = "debug", .key = 128,
847
.doc = "Debug mode", .group = 3 },
848
{ .name = "connect", .key = 'c',
849
.arg = "ADDRESS:PORT",
850
.doc = "Connect directly to a specific Mandos server",
852
{ .name = "interface", .key = 'i',
854
.doc = "Interface that will be used to search for Mandos"
857
{ .name = "seckey", .key = 's',
859
.doc = "OpenPGP secret key file base name",
861
{ .name = "pubkey", .key = 'p',
863
.doc = "OpenPGP public key file base name",
865
{ .name = "dh-bits", .key = 129,
867
.doc = "Bit length of the prime number used in the"
868
" Diffie-Hellman key exchange",
870
{ .name = "priority", .key = 130,
872
.doc = "GnuTLS priority string for the TLS handshake",
877
error_t parse_opt(int key, char *arg,
878
struct argp_state *state) {
880
case 128: /* --debug */
883
case 'c': /* --connect */
886
case 'i': /* --interface */
889
case 's': /* --seckey */
892
case 'p': /* --pubkey */
895
case 129: /* --dh-bits */
896
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
897
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
898
or arg[numchars] != '\0'){
899
fprintf(stderr, "Bad number of DH bits\n");
902
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
904
case 130: /* --priority */
912
return ARGP_ERR_UNKNOWN;
917
struct argp argp = { .options = options, .parser = parse_opt,
919
.doc = "Mandos client -- Get and decrypt"
920
" passwords from a Mandos server" };
921
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
922
if(ret == ARGP_ERR_UNKNOWN){
923
fprintf(stderr, "Unknown error while parsing arguments\n");
924
exitcode = EXIT_FAILURE;
929
/* If the interface is down, bring it up */
931
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
934
exitcode = EXIT_FAILURE;
937
strcpy(network.ifr_name, interface);
938
ret = ioctl(sd, SIOCGIFFLAGS, &network);
940
perror("ioctl SIOCGIFFLAGS");
941
exitcode = EXIT_FAILURE;
944
if((network.ifr_flags & IFF_UP) == 0){
945
network.ifr_flags |= IFF_UP;
946
ret = ioctl(sd, SIOCSIFFLAGS, &network);
948
perror("ioctl SIOCSIFFLAGS");
949
exitcode = EXIT_FAILURE;
953
ret = (int)TEMP_FAILURE_RETRY(close(sd));
972
ret = init_gnutls_global(&mc, pubkey, seckey);
974
fprintf(stderr, "init_gnutls_global failed\n");
975
exitcode = EXIT_FAILURE;
978
gnutls_initialized = true;
981
if(mkdtemp(tempdir) == NULL){
987
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
988
fprintf(stderr, "init_gpgme failed\n");
989
exitcode = EXIT_FAILURE;
992
gpgme_initialized = true;
995
if_index = (AvahiIfIndex) if_nametoindex(interface);
997
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1001
if(connect_to != NULL){
1002
/* Connect directly, do not use Zeroconf */
1003
/* (Mainly meant for debugging) */
1004
char *address = strrchr(connect_to, ':');
1005
if(address == NULL){
1006
fprintf(stderr, "No colon in address\n");
1007
exitcode = EXIT_FAILURE;
1011
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1012
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1013
or address[numchars+1] != '\0'){
1014
fprintf(stderr, "Bad port number\n");
1015
exitcode = EXIT_FAILURE;
1018
port = (uint16_t)tmpmax;
1020
address = connect_to;
1021
ret = start_mandos_communication(address, port, if_index, &mc);
1023
exitcode = EXIT_FAILURE;
1025
exitcode = EXIT_SUCCESS;
1031
avahi_set_log_function(empty_log);
1034
/* Initialize the pseudo-RNG for Avahi */
1035
srand((unsigned int) time(NULL));
1037
/* Allocate main Avahi loop object */
1038
mc.simple_poll = avahi_simple_poll_new();
1039
if(mc.simple_poll == NULL) {
1040
fprintf(stderr, "Avahi: Failed to create simple poll"
1042
exitcode = EXIT_FAILURE;
1047
AvahiServerConfig config;
1048
/* Do not publish any local Zeroconf records */
1049
avahi_server_config_init(&config);
1050
config.publish_hinfo = 0;
1051
config.publish_addresses = 0;
1052
config.publish_workstation = 0;
1053
config.publish_domain = 0;
1055
/* Allocate a new server */
1056
mc.server = avahi_server_new(avahi_simple_poll_get
1057
(mc.simple_poll), &config, NULL,
1060
/* Free the Avahi configuration data */
1061
avahi_server_config_free(&config);
1064
/* Check if creating the Avahi server object succeeded */
1065
if(mc.server == NULL) {
1066
fprintf(stderr, "Failed to create Avahi server: %s\n",
1067
avahi_strerror(error));
1068
exitcode = EXIT_FAILURE;
1072
/* Create the Avahi service browser */
1073
sb = avahi_s_service_browser_new(mc.server, if_index,
1075
"_mandos._tcp", NULL, 0,
1076
browse_callback, &mc);
1078
fprintf(stderr, "Failed to create service browser: %s\n",
1079
avahi_strerror(avahi_server_errno(mc.server)));
1080
exitcode = EXIT_FAILURE;
1084
/* Run the main loop */
1885
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1886
.priority = "SECURE256:!CTYPE-X.509:"
1887
"+CTYPE-OPENPGP", .current_server = NULL,
1888
.interfaces = NULL, .interfaces_size = 0 };
1889
AvahiSServiceBrowser *sb = NULL;
1894
int exitcode = EXIT_SUCCESS;
1895
char *interfaces_to_take_down = NULL;
1896
size_t interfaces_to_take_down_size = 0;
1897
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1898
char old_tempdir[] = "/tmp/mandosXXXXXX";
1899
char *tempdir = NULL;
1900
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1901
const char *seckey = PATHDIR "/" SECKEY;
1902
const char *pubkey = PATHDIR "/" PUBKEY;
1903
char *interfaces_hooks = NULL;
1905
bool gnutls_initialized = false;
1906
bool gpgme_initialized = false;
1908
double retry_interval = 10; /* 10s between trying a server and
1909
retrying the same server again */
1911
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1912
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1917
/* Lower any group privileges we might have, just to be safe */
1921
perror_plus("setgid");
1924
/* Lower user privileges (temporarily) */
1928
perror_plus("seteuid");
1936
struct argp_option options[] = {
1937
{ .name = "debug", .key = 128,
1938
.doc = "Debug mode", .group = 3 },
1939
{ .name = "connect", .key = 'c',
1940
.arg = "ADDRESS:PORT",
1941
.doc = "Connect directly to a specific Mandos server",
1943
{ .name = "interface", .key = 'i',
1945
.doc = "Network interface that will be used to search for"
1948
{ .name = "seckey", .key = 's',
1950
.doc = "OpenPGP secret key file base name",
1952
{ .name = "pubkey", .key = 'p',
1954
.doc = "OpenPGP public key file base name",
1956
{ .name = "dh-bits", .key = 129,
1958
.doc = "Bit length of the prime number used in the"
1959
" Diffie-Hellman key exchange",
1961
{ .name = "priority", .key = 130,
1963
.doc = "GnuTLS priority string for the TLS handshake",
1965
{ .name = "delay", .key = 131,
1967
.doc = "Maximum delay to wait for interface startup",
1969
{ .name = "retry", .key = 132,
1971
.doc = "Retry interval used when denied by the Mandos server",
1973
{ .name = "network-hook-dir", .key = 133,
1975
.doc = "Directory where network hooks are located",
1978
* These reproduce what we would get without ARGP_NO_HELP
1980
{ .name = "help", .key = '?',
1981
.doc = "Give this help list", .group = -1 },
1982
{ .name = "usage", .key = -3,
1983
.doc = "Give a short usage message", .group = -1 },
1984
{ .name = "version", .key = 'V',
1985
.doc = "Print program version", .group = -1 },
1989
error_t parse_opt(int key, char *arg,
1990
struct argp_state *state){
1993
case 128: /* --debug */
1996
case 'c': /* --connect */
1999
case 'i': /* --interface */
2000
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2003
argp_error(state, "%s", strerror(ret_errno));
2006
case 's': /* --seckey */
2009
case 'p': /* --pubkey */
2012
case 129: /* --dh-bits */
2014
tmpmax = strtoimax(arg, &tmp, 10);
2015
if(errno != 0 or tmp == arg or *tmp != '\0'
2016
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2017
argp_error(state, "Bad number of DH bits");
2019
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2021
case 130: /* --priority */
2024
case 131: /* --delay */
2026
delay = strtof(arg, &tmp);
2027
if(errno != 0 or tmp == arg or *tmp != '\0'){
2028
argp_error(state, "Bad delay");
2030
case 132: /* --retry */
2032
retry_interval = strtod(arg, &tmp);
2033
if(errno != 0 or tmp == arg or *tmp != '\0'
2034
or (retry_interval * 1000) > INT_MAX
2035
or retry_interval < 0){
2036
argp_error(state, "Bad retry interval");
2039
case 133: /* --network-hook-dir */
2043
* These reproduce what we would get without ARGP_NO_HELP
2045
case '?': /* --help */
2046
argp_state_help(state, state->out_stream,
2047
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2048
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2049
case -3: /* --usage */
2050
argp_state_help(state, state->out_stream,
2051
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2052
case 'V': /* --version */
2053
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2054
exit(argp_err_exit_status);
2057
return ARGP_ERR_UNKNOWN;
2062
struct argp argp = { .options = options, .parser = parse_opt,
2064
.doc = "Mandos client -- Get and decrypt"
2065
" passwords from a Mandos server" };
2066
ret = argp_parse(&argp, argc, argv,
2067
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2074
perror_plus("argp_parse");
2075
exitcode = EX_OSERR;
2078
exitcode = EX_USAGE;
2084
/* Work around Debian bug #633582:
2085
<http://bugs.debian.org/633582> */
2087
/* Re-raise privileges */
2088
ret_errno = raise_privileges();
2091
perror_plus("Failed to raise privileges");
2095
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2096
int seckey_fd = open(seckey, O_RDONLY);
2097
if(seckey_fd == -1){
2098
perror_plus("open");
2100
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2102
perror_plus("fstat");
2104
if(S_ISREG(st.st_mode)
2105
and st.st_uid == 0 and st.st_gid == 0){
2106
ret = fchown(seckey_fd, uid, gid);
2108
perror_plus("fchown");
2112
TEMP_FAILURE_RETRY(close(seckey_fd));
2116
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2117
int pubkey_fd = open(pubkey, O_RDONLY);
2118
if(pubkey_fd == -1){
2119
perror_plus("open");
2121
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2123
perror_plus("fstat");
2125
if(S_ISREG(st.st_mode)
2126
and st.st_uid == 0 and st.st_gid == 0){
2127
ret = fchown(pubkey_fd, uid, gid);
2129
perror_plus("fchown");
2133
TEMP_FAILURE_RETRY(close(pubkey_fd));
2137
/* Lower privileges */
2138
ret_errno = lower_privileges();
2141
perror_plus("Failed to lower privileges");
2146
/* Remove invalid interface names (except "none") */
2148
char *interface = NULL;
2149
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2151
if(strcmp(interface, "none") != 0
2152
and if_nametoindex(interface) == 0){
2153
if(interface[0] != '\0'){
2154
fprintf_plus(stderr, "Not using nonexisting interface"
2155
" \"%s\"\n", interface);
2157
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2163
/* Run network hooks */
2165
if(mc.interfaces != NULL){
2166
interfaces_hooks = malloc(mc.interfaces_size);
2167
if(interfaces_hooks == NULL){
2168
perror_plus("malloc");
2171
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2172
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2174
run_network_hooks("start", interfaces_hooks != NULL ?
2175
interfaces_hooks : "", delay);
2179
avahi_set_log_function(empty_log);
2182
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2183
from the signal handler */
2184
/* Initialize the pseudo-RNG for Avahi */
2185
srand((unsigned int) time(NULL));
2186
simple_poll = avahi_simple_poll_new();
2187
if(simple_poll == NULL){
2188
fprintf_plus(stderr,
2189
"Avahi: Failed to create simple poll object.\n");
2190
exitcode = EX_UNAVAILABLE;
2194
sigemptyset(&sigterm_action.sa_mask);
2195
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2197
perror_plus("sigaddset");
2198
exitcode = EX_OSERR;
2201
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2203
perror_plus("sigaddset");
2204
exitcode = EX_OSERR;
2207
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2209
perror_plus("sigaddset");
2210
exitcode = EX_OSERR;
2213
/* Need to check if the handler is SIG_IGN before handling:
2214
| [[info:libc:Initial Signal Actions]] |
2215
| [[info:libc:Basic Signal Handling]] |
2217
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2219
perror_plus("sigaction");
2222
if(old_sigterm_action.sa_handler != SIG_IGN){
2223
ret = sigaction(SIGINT, &sigterm_action, NULL);
2225
perror_plus("sigaction");
2226
exitcode = EX_OSERR;
2230
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2232
perror_plus("sigaction");
2235
if(old_sigterm_action.sa_handler != SIG_IGN){
2236
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2238
perror_plus("sigaction");
2239
exitcode = EX_OSERR;
2243
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2245
perror_plus("sigaction");
2248
if(old_sigterm_action.sa_handler != SIG_IGN){
2249
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2251
perror_plus("sigaction");
2252
exitcode = EX_OSERR;
2257
/* If no interfaces were specified, make a list */
2258
if(mc.interfaces == NULL){
2259
struct dirent **direntries = NULL;
2260
/* Look for any good interfaces */
2261
ret = scandir(sys_class_net, &direntries, good_interface,
2264
/* Add all found interfaces to interfaces list */
2265
for(int i = 0; i < ret; ++i){
2266
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2267
direntries[i]->d_name);
2270
perror_plus("argz_add");
2274
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2275
direntries[i]->d_name);
2283
fprintf_plus(stderr, "Could not find a network interface\n");
2284
exitcode = EXIT_FAILURE;
2289
/* Bring up interfaces which are down, and remove any "none"s */
2291
char *interface = NULL;
2292
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2294
/* If interface name is "none", stop bringing up interfaces.
2295
Also remove all instances of "none" from the list */
2296
if(strcmp(interface, "none") == 0){
2297
argz_delete(&mc.interfaces, &mc.interfaces_size,
2300
while((interface = argz_next(mc.interfaces,
2301
mc.interfaces_size, interface))){
2302
if(strcmp(interface, "none") == 0){
2303
argz_delete(&mc.interfaces, &mc.interfaces_size,
2310
bool interface_was_up = interface_is_up(interface);
2311
errno = bring_up_interface(interface, delay);
2312
if(not interface_was_up){
2314
perror_plus("Failed to bring up interface");
2316
errno = argz_add(&interfaces_to_take_down,
2317
&interfaces_to_take_down_size,
2320
perror_plus("argz_add");
2325
if(debug and (interfaces_to_take_down == NULL)){
2326
fprintf_plus(stderr, "No interfaces were brought up\n");
2330
/* If we only got one interface, explicitly use only that one */
2331
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
1087
fprintf(stderr, "Starting Avahi loop search\n");
1090
avahi_simple_poll_loop(mc.simple_poll);
2333
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2336
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2343
ret = init_gnutls_global(pubkey, seckey, &mc);
2345
fprintf_plus(stderr, "init_gnutls_global failed\n");
2346
exitcode = EX_UNAVAILABLE;
2349
gnutls_initialized = true;
2356
/* Try /run/tmp before /tmp */
2357
tempdir = mkdtemp(run_tempdir);
2358
if(tempdir == NULL and errno == ENOENT){
2360
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2361
run_tempdir, old_tempdir);
2363
tempdir = mkdtemp(old_tempdir);
2365
if(tempdir == NULL){
2366
perror_plus("mkdtemp");
2374
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2375
fprintf_plus(stderr, "init_gpgme failed\n");
2376
exitcode = EX_UNAVAILABLE;
2379
gpgme_initialized = true;
2386
if(connect_to != NULL){
2387
/* Connect directly, do not use Zeroconf */
2388
/* (Mainly meant for debugging) */
2389
char *address = strrchr(connect_to, ':');
2391
if(address == NULL){
2392
fprintf_plus(stderr, "No colon in address\n");
2393
exitcode = EX_USAGE;
2403
tmpmax = strtoimax(address+1, &tmp, 10);
2404
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2405
or tmpmax != (in_port_t)tmpmax){
2406
fprintf_plus(stderr, "Bad port number\n");
2407
exitcode = EX_USAGE;
2415
port = (in_port_t)tmpmax;
2417
/* Colon in address indicates IPv6 */
2419
if(strchr(connect_to, ':') != NULL){
2421
/* Accept [] around IPv6 address - see RFC 5952 */
2422
if(connect_to[0] == '[' and address[-1] == ']')
2430
address = connect_to;
2436
while(not quit_now){
2437
ret = start_mandos_communication(address, port, if_index, af,
2439
if(quit_now or ret == 0){
2443
fprintf_plus(stderr, "Retrying in %d seconds\n",
2444
(int)retry_interval);
2446
sleep((unsigned int)retry_interval);
2450
exitcode = EXIT_SUCCESS;
2461
AvahiServerConfig config;
2462
/* Do not publish any local Zeroconf records */
2463
avahi_server_config_init(&config);
2464
config.publish_hinfo = 0;
2465
config.publish_addresses = 0;
2466
config.publish_workstation = 0;
2467
config.publish_domain = 0;
2469
/* Allocate a new server */
2470
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2471
&config, NULL, NULL, &ret_errno);
2473
/* Free the Avahi configuration data */
2474
avahi_server_config_free(&config);
2477
/* Check if creating the Avahi server object succeeded */
2478
if(mc.server == NULL){
2479
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2480
avahi_strerror(ret_errno));
2481
exitcode = EX_UNAVAILABLE;
2489
/* Create the Avahi service browser */
2490
sb = avahi_s_service_browser_new(mc.server, if_index,
2491
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2492
NULL, 0, browse_callback,
2495
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2496
avahi_strerror(avahi_server_errno(mc.server)));
2497
exitcode = EX_UNAVAILABLE;
2505
/* Run the main loop */
2508
fprintf_plus(stderr, "Starting Avahi loop search\n");
2511
ret = avahi_loop_with_timeout(simple_poll,
2512
(int)(retry_interval * 1000), &mc);
2514
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2515
(ret == 0) ? "successfully" : "with error");
1095
fprintf(stderr, "%s exiting\n", argv[0]);
1098
/* Cleanup things */
1100
avahi_s_service_browser_free(sb);
1102
if(mc.server != NULL)
1103
avahi_server_free(mc.server);
1105
if(mc.simple_poll != NULL)
1106
avahi_simple_poll_free(mc.simple_poll);
1108
if(gnutls_initialized){
1109
gnutls_certificate_free_credentials(mc.cred);
1110
gnutls_global_deinit();
1111
gnutls_dh_params_deinit(mc.dh_params);
1114
if(gpgme_initialized){
1115
gpgme_release(mc.ctx);
1118
/* Removes the temp directory used by GPGME */
1119
if(tempdir[0] != '\0'){
1121
struct dirent *direntry;
1122
d = opendir(tempdir);
1124
if(errno != ENOENT){
1129
direntry = readdir(d);
1130
if(direntry == NULL){
1133
if(direntry->d_type == DT_REG){
1134
char *fullname = NULL;
1135
ret = asprintf(&fullname, "%s/%s", tempdir,
1141
ret = unlink(fullname);
1143
fprintf(stderr, "unlink(\"%s\"): %s",
1144
fullname, strerror(errno));
1151
ret = rmdir(tempdir);
1152
if(ret == -1 and errno != ENOENT){
2521
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2524
/* Cleanup things */
2525
free(mc.interfaces);
2528
avahi_s_service_browser_free(sb);
2530
if(mc.server != NULL)
2531
avahi_server_free(mc.server);
2533
if(simple_poll != NULL)
2534
avahi_simple_poll_free(simple_poll);
2536
if(gnutls_initialized){
2537
gnutls_certificate_free_credentials(mc.cred);
2538
gnutls_global_deinit();
2539
gnutls_dh_params_deinit(mc.dh_params);
2542
if(gpgme_initialized){
2543
gpgme_release(mc.ctx);
2546
/* Cleans up the circular linked list of Mandos servers the client
2548
if(mc.current_server != NULL){
2549
mc.current_server->prev->next = NULL;
2550
while(mc.current_server != NULL){
2551
server *next = mc.current_server->next;
2552
free(mc.current_server);
2553
mc.current_server = next;
2557
/* Re-raise privileges */
2559
ret_errno = raise_privileges();
2562
perror_plus("Failed to raise privileges");
2565
/* Run network hooks */
2566
run_network_hooks("stop", interfaces_hooks != NULL ?
2567
interfaces_hooks : "", delay);
2569
/* Take down the network interfaces which were brought up */
2571
char *interface = NULL;
2572
while((interface=argz_next(interfaces_to_take_down,
2573
interfaces_to_take_down_size,
2575
ret_errno = take_down_interface(interface);
2578
perror_plus("Failed to take down interface");
2581
if(debug and (interfaces_to_take_down == NULL)){
2582
fprintf_plus(stderr, "No interfaces needed to be taken"
2588
ret_errno = lower_privileges_permanently();
2591
perror_plus("Failed to lower privileges permanently");
2595
free(interfaces_to_take_down);
2596
free(interfaces_hooks);
2598
/* Removes the GPGME temp directory and all files inside */
2599
if(tempdir != NULL){
2600
struct dirent **direntries = NULL;
2601
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2603
if(tempdir_fd == -1){
2604
perror_plus("open");
2607
#if __GLIBC_PREREQ(2, 15)
2608
int numentries = scandirat(tempdir_fd, ".", &direntries,
2609
notdotentries, alphasort);
2610
#else /* not __GLIBC_PREREQ(2, 15) */
2611
int numentries = scandir(tempdir, &direntries, notdotentries,
2613
#endif /* not __GLIBC_PREREQ(2, 15) */
2614
#else /* not __GLIBC__ */
2615
int numentries = scandir(tempdir, &direntries, notdotentries,
2617
#endif /* not __GLIBC__ */
2618
if(numentries >= 0){
2619
for(int i = 0; i < numentries; i++){
2620
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2622
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2623
" \"%s\", 0): %s\n", tempdir,
2624
direntries[i]->d_name, strerror(errno));
2628
/* need to clean even if 0 because man page doesn't specify */
2630
if(numentries == -1){
2631
perror_plus("scandir");
2633
ret = rmdir(tempdir);
2634
if(ret == -1 and errno != ENOENT){
2635
perror_plus("rmdir");
2638
TEMP_FAILURE_RETRY(close(tempdir_fd));
2643
sigemptyset(&old_sigterm_action.sa_mask);
2644
old_sigterm_action.sa_handler = SIG_DFL;
2645
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2646
&old_sigterm_action,
2649
perror_plus("sigaction");
2652
ret = raise(signal_received);
2653
} while(ret != 0 and errno == EINTR);
2655
perror_plus("raise");
2658
TEMP_FAILURE_RETRY(pause());