811
1170
case AVAHI_BROWSER_ALL_FOR_NOW:
812
1171
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
fprintf(stderr, "No Mandos server found, still searching...\n");
1173
fprintf_plus(stderr, "No Mandos server found, still"
1180
/* Signal handler that stops main loop after SIGTERM */
1181
static void handle_sigterm(int sig){
1186
signal_received = sig;
1187
int old_errno = errno;
1188
/* set main loop to exit */
1189
if(simple_poll != NULL){
1190
avahi_simple_poll_quit(simple_poll);
1195
__attribute__((nonnull, warn_unused_result))
1196
bool get_flags(const char *ifname, struct ifreq *ifr){
1200
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1203
perror_plus("socket");
1207
strcpy(ifr->ifr_name, ifname);
1208
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1212
perror_plus("ioctl SIOCGIFFLAGS");
1220
__attribute__((nonnull, warn_unused_result))
1221
bool good_flags(const char *ifname, const struct ifreq *ifr){
1223
/* Reject the loopback device */
1224
if(ifr->ifr_flags & IFF_LOOPBACK){
1226
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1231
/* Accept point-to-point devices only if connect_to is specified */
1232
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1234
fprintf_plus(stderr, "Accepting point-to-point interface"
1235
" \"%s\"\n", ifname);
1239
/* Otherwise, reject non-broadcast-capable devices */
1240
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1242
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1243
" \"%s\"\n", ifname);
1247
/* Reject non-ARP interfaces (including dummy interfaces) */
1248
if(ifr->ifr_flags & IFF_NOARP){
1250
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1256
/* Accept this device */
1258
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1264
* This function determines if a directory entry in /sys/class/net
1265
* corresponds to an acceptable network device.
1266
* (This function is passed to scandir(3) as a filter function.)
1268
__attribute__((nonnull, warn_unused_result))
1269
int good_interface(const struct dirent *if_entry){
1270
if(if_entry->d_name[0] == '.'){
1275
if(not get_flags(if_entry->d_name, &ifr)){
1277
fprintf_plus(stderr, "Failed to get flags for interface "
1278
"\"%s\"\n", if_entry->d_name);
1283
if(not good_flags(if_entry->d_name, &ifr)){
1290
* This function determines if a network interface is up.
1292
__attribute__((nonnull, warn_unused_result))
1293
bool interface_is_up(const char *interface){
1295
if(not get_flags(interface, &ifr)){
1297
fprintf_plus(stderr, "Failed to get flags for interface "
1298
"\"%s\"\n", interface);
1303
return (bool)(ifr.ifr_flags & IFF_UP);
1307
* This function determines if a network interface is running
1309
__attribute__((nonnull, warn_unused_result))
1310
bool interface_is_running(const char *interface){
1312
if(not get_flags(interface, &ifr)){
1314
fprintf_plus(stderr, "Failed to get flags for interface "
1315
"\"%s\"\n", interface);
1320
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1323
__attribute__((nonnull, pure, warn_unused_result))
1324
int notdotentries(const struct dirent *direntry){
1325
/* Skip "." and ".." */
1326
if(direntry->d_name[0] == '.'
1327
and (direntry->d_name[1] == '\0'
1328
or (direntry->d_name[1] == '.'
1329
and direntry->d_name[2] == '\0'))){
1335
/* Is this directory entry a runnable program? */
1336
__attribute__((nonnull, warn_unused_result))
1337
int runnable_hook(const struct dirent *direntry){
1342
if((direntry->d_name)[0] == '\0'){
1347
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1348
"abcdefghijklmnopqrstuvwxyz"
1351
if((direntry->d_name)[sret] != '\0'){
1352
/* Contains non-allowed characters */
1354
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1360
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1363
perror_plus("Could not stat hook");
1367
if(not (S_ISREG(st.st_mode))){
1368
/* Not a regular file */
1370
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1375
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1376
/* Not executable */
1378
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1384
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1390
__attribute__((nonnull, warn_unused_result))
1391
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1392
mandos_context *mc){
1394
struct timespec now;
1395
struct timespec waited_time;
1396
intmax_t block_time;
1399
if(mc->current_server == NULL){
1401
fprintf_plus(stderr, "Wait until first server is found."
1404
ret = avahi_simple_poll_iterate(s, -1);
1407
fprintf_plus(stderr, "Check current_server if we should run"
1410
/* the current time */
1411
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1413
perror_plus("clock_gettime");
1416
/* Calculating in ms how long time between now and server
1417
who we visted longest time ago. Now - last seen. */
1418
waited_time.tv_sec = (now.tv_sec
1419
- mc->current_server->last_seen.tv_sec);
1420
waited_time.tv_nsec = (now.tv_nsec
1421
- mc->current_server->last_seen.tv_nsec);
1422
/* total time is 10s/10,000ms.
1423
Converting to s from ms by dividing by 1,000,
1424
and ns to ms by dividing by 1,000,000. */
1425
block_time = ((retry_interval
1426
- ((intmax_t)waited_time.tv_sec * 1000))
1427
- ((intmax_t)waited_time.tv_nsec / 1000000));
1430
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1434
if(block_time <= 0){
1435
ret = start_mandos_communication(mc->current_server->ip,
1436
mc->current_server->port,
1437
mc->current_server->if_index,
1438
mc->current_server->af, mc);
1440
avahi_simple_poll_quit(s);
1443
ret = clock_gettime(CLOCK_MONOTONIC,
1444
&mc->current_server->last_seen);
1446
perror_plus("clock_gettime");
1449
mc->current_server = mc->current_server->next;
1450
block_time = 0; /* Call avahi to find new Mandos
1451
servers, but don't block */
1454
ret = avahi_simple_poll_iterate(s, (int)block_time);
1457
if(ret > 0 or errno != EINTR){
1458
return (ret != 1) ? ret : 0;
1464
/* Set effective uid to 0, return errno */
1465
__attribute__((warn_unused_result))
1466
error_t raise_privileges(void){
1467
error_t old_errno = errno;
1468
error_t ret_errno = 0;
1469
if(seteuid(0) == -1){
1476
/* Set effective and real user ID to 0. Return errno. */
1477
__attribute__((warn_unused_result))
1478
error_t raise_privileges_permanently(void){
1479
error_t old_errno = errno;
1480
error_t ret_errno = raise_privileges();
1485
if(setuid(0) == -1){
1492
/* Set effective user ID to unprivileged saved user ID */
1493
__attribute__((warn_unused_result))
1494
error_t lower_privileges(void){
1495
error_t old_errno = errno;
1496
error_t ret_errno = 0;
1497
if(seteuid(uid) == -1){
1504
/* Lower privileges permanently */
1505
__attribute__((warn_unused_result))
1506
error_t lower_privileges_permanently(void){
1507
error_t old_errno = errno;
1508
error_t ret_errno = 0;
1509
if(setuid(uid) == -1){
1516
__attribute__((nonnull))
1517
void run_network_hooks(const char *mode, const char *interface,
1519
struct dirent **direntries = NULL;
1520
if(hookdir_fd == -1){
1521
hookdir_fd = open(hookdir, O_RDONLY);
1522
if(hookdir_fd == -1){
1523
if(errno == ENOENT){
1525
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1526
" found\n", hookdir);
1529
perror_plus("open");
1535
#if __GLIBC_PREREQ(2, 15)
1536
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1537
runnable_hook, alphasort);
1538
#else /* not __GLIBC_PREREQ(2, 15) */
1539
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1541
#endif /* not __GLIBC_PREREQ(2, 15) */
1542
#else /* not __GLIBC__ */
1543
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1545
#endif /* not __GLIBC__ */
1547
perror_plus("scandir");
1550
struct dirent *direntry;
1552
int devnull = open("/dev/null", O_RDONLY);
1553
for(int i = 0; i < numhooks; i++){
1554
direntry = direntries[i];
1556
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1559
pid_t hook_pid = fork();
1562
/* Raise privileges */
1563
errno = raise_privileges_permanently();
1565
perror_plus("Failed to raise privileges");
1572
perror_plus("setgid");
1575
/* Reset supplementary groups */
1577
ret = setgroups(0, NULL);
1579
perror_plus("setgroups");
1582
ret = dup2(devnull, STDIN_FILENO);
1584
perror_plus("dup2(devnull, STDIN_FILENO)");
1587
ret = close(devnull);
1589
perror_plus("close");
1592
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1594
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1597
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1599
perror_plus("setenv");
1602
ret = setenv("DEVICE", interface, 1);
1604
perror_plus("setenv");
1607
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1609
perror_plus("setenv");
1612
ret = setenv("MODE", mode, 1);
1614
perror_plus("setenv");
1618
ret = asprintf(&delaystring, "%f", (double)delay);
1620
perror_plus("asprintf");
1623
ret = setenv("DELAY", delaystring, 1);
1626
perror_plus("setenv");
1630
if(connect_to != NULL){
1631
ret = setenv("CONNECT", connect_to, 1);
1633
perror_plus("setenv");
1637
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1639
perror_plus("openat");
1640
_exit(EXIT_FAILURE);
1642
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1643
perror_plus("close");
1644
_exit(EXIT_FAILURE);
1646
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1648
perror_plus("fexecve");
1649
_exit(EXIT_FAILURE);
1653
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1654
perror_plus("waitpid");
1657
if(WIFEXITED(status)){
1658
if(WEXITSTATUS(status) != 0){
1659
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1660
" with status %d\n", direntry->d_name,
1661
WEXITSTATUS(status));
1664
} else if(WIFSIGNALED(status)){
1665
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1666
" signal %d\n", direntry->d_name,
1670
fprintf_plus(stderr, "Warning: network hook \"%s\""
1671
" crashed\n", direntry->d_name);
1676
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1681
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1682
perror_plus("close");
1689
__attribute__((nonnull, warn_unused_result))
1690
error_t bring_up_interface(const char *const interface,
1692
error_t old_errno = errno;
1694
struct ifreq network;
1695
unsigned int if_index = if_nametoindex(interface);
1697
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1707
if(not interface_is_up(interface)){
1708
error_t ret_errno = 0, ioctl_errno = 0;
1709
if(not get_flags(interface, &network)){
1711
fprintf_plus(stderr, "Failed to get flags for interface "
1712
"\"%s\"\n", interface);
1716
network.ifr_flags |= IFF_UP; /* set flag */
1718
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1721
perror_plus("socket");
1727
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1729
perror_plus("close");
1736
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1740
/* Raise privileges */
1741
ret_errno = raise_privileges();
1744
perror_plus("Failed to raise privileges");
1749
bool restore_loglevel = false;
1751
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1752
messages about the network interface to mess up the prompt */
1753
ret_linux = klogctl(8, NULL, 5);
1754
if(ret_linux == -1){
1755
perror_plus("klogctl");
1757
restore_loglevel = true;
1760
#endif /* __linux__ */
1761
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1762
ioctl_errno = errno;
1764
if(restore_loglevel){
1765
ret_linux = klogctl(7, NULL, 0);
1766
if(ret_linux == -1){
1767
perror_plus("klogctl");
1770
#endif /* __linux__ */
1772
/* If raise_privileges() succeeded above */
1774
/* Lower privileges */
1775
ret_errno = lower_privileges();
1778
perror_plus("Failed to lower privileges");
1782
/* Close the socket */
1783
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1785
perror_plus("close");
1788
if(ret_setflags == -1){
1789
errno = ioctl_errno;
1790
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1795
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1799
/* Sleep checking until interface is running.
1800
Check every 0.25s, up to total time of delay */
1801
for(int i=0; i < delay * 4; i++){
1802
if(interface_is_running(interface)){
1805
struct timespec sleeptime = { .tv_nsec = 250000000 };
1806
ret = nanosleep(&sleeptime, NULL);
1807
if(ret == -1 and errno != EINTR){
1808
perror_plus("nanosleep");
1816
__attribute__((nonnull, warn_unused_result))
1817
error_t take_down_interface(const char *const interface){
1818
error_t old_errno = errno;
1819
struct ifreq network;
1820
unsigned int if_index = if_nametoindex(interface);
1822
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1826
if(interface_is_up(interface)){
1827
error_t ret_errno = 0, ioctl_errno = 0;
1828
if(not get_flags(interface, &network) and debug){
1830
fprintf_plus(stderr, "Failed to get flags for interface "
1831
"\"%s\"\n", interface);
1835
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1837
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1840
perror_plus("socket");
1846
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1850
/* Raise privileges */
1851
ret_errno = raise_privileges();
1854
perror_plus("Failed to raise privileges");
1857
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1858
ioctl_errno = errno;
1860
/* If raise_privileges() succeeded above */
1862
/* Lower privileges */
1863
ret_errno = lower_privileges();
1866
perror_plus("Failed to lower privileges");
1870
/* Close the socket */
1871
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1873
perror_plus("close");
1876
if(ret_setflags == -1){
1877
errno = ioctl_errno;
1878
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1883
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
820
1891
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 */
1892
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1893
.priority = "SECURE256:!CTYPE-X.509:"
1894
"+CTYPE-OPENPGP", .current_server = NULL,
1895
.interfaces = NULL, .interfaces_size = 0 };
1896
AvahiSServiceBrowser *sb = NULL;
1901
int exitcode = EXIT_SUCCESS;
1902
char *interfaces_to_take_down = NULL;
1903
size_t interfaces_to_take_down_size = 0;
1904
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1905
char old_tempdir[] = "/tmp/mandosXXXXXX";
1906
char *tempdir = NULL;
1907
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1908
const char *seckey = PATHDIR "/" SECKEY;
1909
const char *pubkey = PATHDIR "/" PUBKEY;
1910
char *interfaces_hooks = NULL;
1912
bool gnutls_initialized = false;
1913
bool gpgme_initialized = false;
1915
double retry_interval = 10; /* 10s between trying a server and
1916
retrying the same server again */
1918
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1919
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1924
/* Lower any group privileges we might have, just to be safe */
1928
perror_plus("setgid");
1931
/* Lower user privileges (temporarily) */
1935
perror_plus("seteuid");
1943
struct argp_option options[] = {
1944
{ .name = "debug", .key = 128,
1945
.doc = "Debug mode", .group = 3 },
1946
{ .name = "connect", .key = 'c',
1947
.arg = "ADDRESS:PORT",
1948
.doc = "Connect directly to a specific Mandos server",
1950
{ .name = "interface", .key = 'i',
1952
.doc = "Network interface that will be used to search for"
1955
{ .name = "seckey", .key = 's',
1957
.doc = "OpenPGP secret key file base name",
1959
{ .name = "pubkey", .key = 'p',
1961
.doc = "OpenPGP public key file base name",
1963
{ .name = "dh-bits", .key = 129,
1965
.doc = "Bit length of the prime number used in the"
1966
" Diffie-Hellman key exchange",
1968
{ .name = "priority", .key = 130,
1970
.doc = "GnuTLS priority string for the TLS handshake",
1972
{ .name = "delay", .key = 131,
1974
.doc = "Maximum delay to wait for interface startup",
1976
{ .name = "retry", .key = 132,
1978
.doc = "Retry interval used when denied by the Mandos server",
1980
{ .name = "network-hook-dir", .key = 133,
1982
.doc = "Directory where network hooks are located",
1985
* These reproduce what we would get without ARGP_NO_HELP
1987
{ .name = "help", .key = '?',
1988
.doc = "Give this help list", .group = -1 },
1989
{ .name = "usage", .key = -3,
1990
.doc = "Give a short usage message", .group = -1 },
1991
{ .name = "version", .key = 'V',
1992
.doc = "Print program version", .group = -1 },
1996
error_t parse_opt(int key, char *arg,
1997
struct argp_state *state){
2000
case 128: /* --debug */
2003
case 'c': /* --connect */
2006
case 'i': /* --interface */
2007
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2010
argp_error(state, "%s", strerror(ret_errno));
2013
case 's': /* --seckey */
2016
case 'p': /* --pubkey */
2019
case 129: /* --dh-bits */
2021
tmpmax = strtoimax(arg, &tmp, 10);
2022
if(errno != 0 or tmp == arg or *tmp != '\0'
2023
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2024
argp_error(state, "Bad number of DH bits");
2026
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2028
case 130: /* --priority */
2031
case 131: /* --delay */
2033
delay = strtof(arg, &tmp);
2034
if(errno != 0 or tmp == arg or *tmp != '\0'){
2035
argp_error(state, "Bad delay");
2037
case 132: /* --retry */
2039
retry_interval = strtod(arg, &tmp);
2040
if(errno != 0 or tmp == arg or *tmp != '\0'
2041
or (retry_interval * 1000) > INT_MAX
2042
or retry_interval < 0){
2043
argp_error(state, "Bad retry interval");
2046
case 133: /* --network-hook-dir */
2050
* These reproduce what we would get without ARGP_NO_HELP
2052
case '?': /* --help */
2053
argp_state_help(state, state->out_stream,
2054
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2055
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2056
case -3: /* --usage */
2057
argp_state_help(state, state->out_stream,
2058
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2059
case 'V': /* --version */
2060
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2061
exit(argp_err_exit_status);
2064
return ARGP_ERR_UNKNOWN;
2069
struct argp argp = { .options = options, .parser = parse_opt,
2071
.doc = "Mandos client -- Get and decrypt"
2072
" passwords from a Mandos server" };
2073
ret = argp_parse(&argp, argc, argv,
2074
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2081
perror_plus("argp_parse");
2082
exitcode = EX_OSERR;
2085
exitcode = EX_USAGE;
2091
/* Work around Debian bug #633582:
2092
<http://bugs.debian.org/633582> */
2094
/* Re-raise privileges */
2095
ret_errno = raise_privileges();
2098
perror_plus("Failed to raise privileges");
2102
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2103
int seckey_fd = open(seckey, O_RDONLY);
2104
if(seckey_fd == -1){
2105
perror_plus("open");
2107
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2109
perror_plus("fstat");
2111
if(S_ISREG(st.st_mode)
2112
and st.st_uid == 0 and st.st_gid == 0){
2113
ret = fchown(seckey_fd, uid, gid);
2115
perror_plus("fchown");
2119
TEMP_FAILURE_RETRY(close(seckey_fd));
2123
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2124
int pubkey_fd = open(pubkey, O_RDONLY);
2125
if(pubkey_fd == -1){
2126
perror_plus("open");
2128
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2130
perror_plus("fstat");
2132
if(S_ISREG(st.st_mode)
2133
and st.st_uid == 0 and st.st_gid == 0){
2134
ret = fchown(pubkey_fd, uid, gid);
2136
perror_plus("fchown");
2140
TEMP_FAILURE_RETRY(close(pubkey_fd));
2144
/* Lower privileges */
2145
ret_errno = lower_privileges();
2148
perror_plus("Failed to lower privileges");
2153
/* Remove invalid interface names (except "none") */
2155
char *interface = NULL;
2156
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2158
if(strcmp(interface, "none") != 0
2159
and if_nametoindex(interface) == 0){
2160
if(interface[0] != '\0'){
2161
fprintf_plus(stderr, "Not using nonexisting interface"
2162
" \"%s\"\n", interface);
2164
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2170
/* Run network hooks */
2172
if(mc.interfaces != NULL){
2173
interfaces_hooks = malloc(mc.interfaces_size);
2174
if(interfaces_hooks == NULL){
2175
perror_plus("malloc");
2178
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2179
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2181
run_network_hooks("start", interfaces_hooks != NULL ?
2182
interfaces_hooks : "", delay);
2186
avahi_set_log_function(empty_log);
2189
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2190
from the signal handler */
2191
/* Initialize the pseudo-RNG for Avahi */
2192
srand((unsigned int) time(NULL));
2193
simple_poll = avahi_simple_poll_new();
2194
if(simple_poll == NULL){
2195
fprintf_plus(stderr,
2196
"Avahi: Failed to create simple poll object.\n");
2197
exitcode = EX_UNAVAILABLE;
2201
sigemptyset(&sigterm_action.sa_mask);
2202
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2204
perror_plus("sigaddset");
2205
exitcode = EX_OSERR;
2208
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2210
perror_plus("sigaddset");
2211
exitcode = EX_OSERR;
2214
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2216
perror_plus("sigaddset");
2217
exitcode = EX_OSERR;
2220
/* Need to check if the handler is SIG_IGN before handling:
2221
| [[info:libc:Initial Signal Actions]] |
2222
| [[info:libc:Basic Signal Handling]] |
2224
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2226
perror_plus("sigaction");
2229
if(old_sigterm_action.sa_handler != SIG_IGN){
2230
ret = sigaction(SIGINT, &sigterm_action, NULL);
2232
perror_plus("sigaction");
2233
exitcode = EX_OSERR;
2237
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2239
perror_plus("sigaction");
2242
if(old_sigterm_action.sa_handler != SIG_IGN){
2243
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2245
perror_plus("sigaction");
2246
exitcode = EX_OSERR;
2250
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2252
perror_plus("sigaction");
2255
if(old_sigterm_action.sa_handler != SIG_IGN){
2256
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2258
perror_plus("sigaction");
2259
exitcode = EX_OSERR;
2264
/* If no interfaces were specified, make a list */
2265
if(mc.interfaces == NULL){
2266
struct dirent **direntries = NULL;
2267
/* Look for any good interfaces */
2268
ret = scandir(sys_class_net, &direntries, good_interface,
2271
/* Add all found interfaces to interfaces list */
2272
for(int i = 0; i < ret; ++i){
2273
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2274
direntries[i]->d_name);
2277
perror_plus("argz_add");
2281
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2282
direntries[i]->d_name);
2290
fprintf_plus(stderr, "Could not find a network interface\n");
2291
exitcode = EXIT_FAILURE;
2296
/* Bring up interfaces which are down, and remove any "none"s */
2298
char *interface = NULL;
2299
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2301
/* If interface name is "none", stop bringing up interfaces.
2302
Also remove all instances of "none" from the list */
2303
if(strcmp(interface, "none") == 0){
2304
argz_delete(&mc.interfaces, &mc.interfaces_size,
2307
while((interface = argz_next(mc.interfaces,
2308
mc.interfaces_size, interface))){
2309
if(strcmp(interface, "none") == 0){
2310
argz_delete(&mc.interfaces, &mc.interfaces_size,
2317
bool interface_was_up = interface_is_up(interface);
2318
errno = bring_up_interface(interface, delay);
2319
if(not interface_was_up){
2321
perror_plus("Failed to bring up interface");
2323
errno = argz_add(&interfaces_to_take_down,
2324
&interfaces_to_take_down_size,
2327
perror_plus("argz_add");
2332
if(debug and (interfaces_to_take_down == NULL)){
2333
fprintf_plus(stderr, "No interfaces were brought up\n");
2337
/* If we only got one interface, explicitly use only that one */
2338
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);
2340
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2343
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2350
ret = init_gnutls_global(pubkey, seckey, &mc);
2352
fprintf_plus(stderr, "init_gnutls_global failed\n");
2353
exitcode = EX_UNAVAILABLE;
2356
gnutls_initialized = true;
2363
/* Try /run/tmp before /tmp */
2364
tempdir = mkdtemp(run_tempdir);
2365
if(tempdir == NULL and errno == ENOENT){
2367
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2368
run_tempdir, old_tempdir);
2370
tempdir = mkdtemp(old_tempdir);
2372
if(tempdir == NULL){
2373
perror_plus("mkdtemp");
2381
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2382
fprintf_plus(stderr, "init_gpgme failed\n");
2383
exitcode = EX_UNAVAILABLE;
2386
gpgme_initialized = true;
2393
if(connect_to != NULL){
2394
/* Connect directly, do not use Zeroconf */
2395
/* (Mainly meant for debugging) */
2396
char *address = strrchr(connect_to, ':');
2398
if(address == NULL){
2399
fprintf_plus(stderr, "No colon in address\n");
2400
exitcode = EX_USAGE;
2410
tmpmax = strtoimax(address+1, &tmp, 10);
2411
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2412
or tmpmax != (in_port_t)tmpmax){
2413
fprintf_plus(stderr, "Bad port number\n");
2414
exitcode = EX_USAGE;
2422
port = (in_port_t)tmpmax;
2424
/* Colon in address indicates IPv6 */
2426
if(strchr(connect_to, ':') != NULL){
2428
/* Accept [] around IPv6 address - see RFC 5952 */
2429
if(connect_to[0] == '[' and address[-1] == ']')
2437
address = connect_to;
2443
while(not quit_now){
2444
ret = start_mandos_communication(address, port, if_index, af,
2446
if(quit_now or ret == 0){
2450
fprintf_plus(stderr, "Retrying in %d seconds\n",
2451
(int)retry_interval);
2453
sleep((unsigned int)retry_interval);
2457
exitcode = EXIT_SUCCESS;
2468
AvahiServerConfig config;
2469
/* Do not publish any local Zeroconf records */
2470
avahi_server_config_init(&config);
2471
config.publish_hinfo = 0;
2472
config.publish_addresses = 0;
2473
config.publish_workstation = 0;
2474
config.publish_domain = 0;
2476
/* Allocate a new server */
2477
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2478
&config, NULL, NULL, &ret_errno);
2480
/* Free the Avahi configuration data */
2481
avahi_server_config_free(&config);
2484
/* Check if creating the Avahi server object succeeded */
2485
if(mc.server == NULL){
2486
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2487
avahi_strerror(ret_errno));
2488
exitcode = EX_UNAVAILABLE;
2496
/* Create the Avahi service browser */
2497
sb = avahi_s_service_browser_new(mc.server, if_index,
2498
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2499
NULL, 0, browse_callback,
2502
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2503
avahi_strerror(avahi_server_errno(mc.server)));
2504
exitcode = EX_UNAVAILABLE;
2512
/* Run the main loop */
2515
fprintf_plus(stderr, "Starting Avahi loop search\n");
2518
ret = avahi_loop_with_timeout(simple_poll,
2519
(int)(retry_interval * 1000), &mc);
2521
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2522
(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){
2528
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2531
/* Cleanup things */
2532
free(mc.interfaces);
2535
avahi_s_service_browser_free(sb);
2537
if(mc.server != NULL)
2538
avahi_server_free(mc.server);
2540
if(simple_poll != NULL)
2541
avahi_simple_poll_free(simple_poll);
2543
if(gnutls_initialized){
2544
gnutls_certificate_free_credentials(mc.cred);
2545
gnutls_global_deinit();
2546
gnutls_dh_params_deinit(mc.dh_params);
2549
if(gpgme_initialized){
2550
gpgme_release(mc.ctx);
2553
/* Cleans up the circular linked list of Mandos servers the client
2555
if(mc.current_server != NULL){
2556
mc.current_server->prev->next = NULL;
2557
while(mc.current_server != NULL){
2558
server *next = mc.current_server->next;
2560
#pragma GCC diagnostic push
2561
#pragma GCC diagnostic ignored "-Wcast-qual"
2563
free((char *)(mc.current_server->ip));
2565
#pragma GCC diagnostic pop
2567
free(mc.current_server);
2568
mc.current_server = next;
2572
/* Re-raise privileges */
2574
ret_errno = raise_privileges();
2577
perror_plus("Failed to raise privileges");
2580
/* Run network hooks */
2581
run_network_hooks("stop", interfaces_hooks != NULL ?
2582
interfaces_hooks : "", delay);
2584
/* Take down the network interfaces which were brought up */
2586
char *interface = NULL;
2587
while((interface=argz_next(interfaces_to_take_down,
2588
interfaces_to_take_down_size,
2590
ret_errno = take_down_interface(interface);
2593
perror_plus("Failed to take down interface");
2596
if(debug and (interfaces_to_take_down == NULL)){
2597
fprintf_plus(stderr, "No interfaces needed to be taken"
2603
ret_errno = lower_privileges_permanently();
2606
perror_plus("Failed to lower privileges permanently");
2610
free(interfaces_to_take_down);
2611
free(interfaces_hooks);
2613
/* Removes the GPGME temp directory and all files inside */
2614
if(tempdir != NULL){
2615
struct dirent **direntries = NULL;
2616
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2618
if(tempdir_fd == -1){
2619
perror_plus("open");
2622
#if __GLIBC_PREREQ(2, 15)
2623
int numentries = scandirat(tempdir_fd, ".", &direntries,
2624
notdotentries, alphasort);
2625
#else /* not __GLIBC_PREREQ(2, 15) */
2626
int numentries = scandir(tempdir, &direntries, notdotentries,
2628
#endif /* not __GLIBC_PREREQ(2, 15) */
2629
#else /* not __GLIBC__ */
2630
int numentries = scandir(tempdir, &direntries, notdotentries,
2632
#endif /* not __GLIBC__ */
2633
if(numentries >= 0){
2634
for(int i = 0; i < numentries; i++){
2635
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2637
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2638
" \"%s\", 0): %s\n", tempdir,
2639
direntries[i]->d_name, strerror(errno));
2643
/* need to clean even if 0 because man page doesn't specify */
2645
if(numentries == -1){
2646
perror_plus("scandir");
2648
ret = rmdir(tempdir);
2649
if(ret == -1 and errno != ENOENT){
2650
perror_plus("rmdir");
2653
TEMP_FAILURE_RETRY(close(tempdir_fd));
2658
sigemptyset(&old_sigterm_action.sa_mask);
2659
old_sigterm_action.sa_handler = SIG_DFL;
2660
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2661
&old_sigterm_action,
2664
perror_plus("sigaction");
2667
ret = raise(signal_received);
2668
} while(ret != 0 and errno == EINTR);
2670
perror_plus("raise");
2673
TEMP_FAILURE_RETRY(pause());