811
1171
case AVAHI_BROWSER_ALL_FOR_NOW:
812
1172
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
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
perror_plus("fork");
1659
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1660
perror_plus("waitpid");
1664
if(WIFEXITED(status)){
1665
if(WEXITSTATUS(status) != 0){
1666
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1667
" with status %d\n", direntry->d_name,
1668
WEXITSTATUS(status));
1672
} else if(WIFSIGNALED(status)){
1673
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1674
" signal %d\n", direntry->d_name,
1679
fprintf_plus(stderr, "Warning: network hook \"%s\""
1680
" crashed\n", direntry->d_name);
1686
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1692
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1693
perror_plus("close");
1700
__attribute__((nonnull, warn_unused_result))
1701
error_t bring_up_interface(const char *const interface,
1703
error_t old_errno = errno;
1705
struct ifreq network;
1706
unsigned int if_index = if_nametoindex(interface);
1708
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1718
if(not interface_is_up(interface)){
1719
error_t ret_errno = 0, ioctl_errno = 0;
1720
if(not get_flags(interface, &network)){
1722
fprintf_plus(stderr, "Failed to get flags for interface "
1723
"\"%s\"\n", interface);
1727
network.ifr_flags |= IFF_UP; /* set flag */
1729
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1732
perror_plus("socket");
1738
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1740
perror_plus("close");
1747
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1751
/* Raise privileges */
1752
ret_errno = raise_privileges();
1755
perror_plus("Failed to raise privileges");
1760
bool restore_loglevel = false;
1762
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1763
messages about the network interface to mess up the prompt */
1764
ret_linux = klogctl(8, NULL, 5);
1765
if(ret_linux == -1){
1766
perror_plus("klogctl");
1768
restore_loglevel = true;
1771
#endif /* __linux__ */
1772
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1773
ioctl_errno = errno;
1775
if(restore_loglevel){
1776
ret_linux = klogctl(7, NULL, 0);
1777
if(ret_linux == -1){
1778
perror_plus("klogctl");
1781
#endif /* __linux__ */
1783
/* If raise_privileges() succeeded above */
1785
/* Lower privileges */
1786
ret_errno = lower_privileges();
1789
perror_plus("Failed to lower privileges");
1793
/* Close the socket */
1794
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1796
perror_plus("close");
1799
if(ret_setflags == -1){
1800
errno = ioctl_errno;
1801
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1806
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1810
/* Sleep checking until interface is running.
1811
Check every 0.25s, up to total time of delay */
1812
for(int i=0; i < delay * 4; i++){
1813
if(interface_is_running(interface)){
1816
struct timespec sleeptime = { .tv_nsec = 250000000 };
1817
ret = nanosleep(&sleeptime, NULL);
1818
if(ret == -1 and errno != EINTR){
1819
perror_plus("nanosleep");
1827
__attribute__((nonnull, warn_unused_result))
1828
error_t take_down_interface(const char *const interface){
1829
error_t old_errno = errno;
1830
struct ifreq network;
1831
unsigned int if_index = if_nametoindex(interface);
1833
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1837
if(interface_is_up(interface)){
1838
error_t ret_errno = 0, ioctl_errno = 0;
1839
if(not get_flags(interface, &network) and debug){
1841
fprintf_plus(stderr, "Failed to get flags for interface "
1842
"\"%s\"\n", interface);
1846
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1848
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1851
perror_plus("socket");
1857
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1861
/* Raise privileges */
1862
ret_errno = raise_privileges();
1865
perror_plus("Failed to raise privileges");
1868
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1869
ioctl_errno = errno;
1871
/* If raise_privileges() succeeded above */
1873
/* Lower privileges */
1874
ret_errno = lower_privileges();
1877
perror_plus("Failed to lower privileges");
1881
/* Close the socket */
1882
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1884
perror_plus("close");
1887
if(ret_setflags == -1){
1888
errno = ioctl_errno;
1889
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1894
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
820
1902
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 */
1903
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1904
.priority = "SECURE256:!CTYPE-X.509:"
1905
"+CTYPE-OPENPGP", .current_server = NULL,
1906
.interfaces = NULL, .interfaces_size = 0 };
1907
AvahiSServiceBrowser *sb = NULL;
1912
int exitcode = EXIT_SUCCESS;
1913
char *interfaces_to_take_down = NULL;
1914
size_t interfaces_to_take_down_size = 0;
1915
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1916
char old_tempdir[] = "/tmp/mandosXXXXXX";
1917
char *tempdir = NULL;
1918
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1919
const char *seckey = PATHDIR "/" SECKEY;
1920
const char *pubkey = PATHDIR "/" PUBKEY;
1921
char *interfaces_hooks = NULL;
1923
bool gnutls_initialized = false;
1924
bool gpgme_initialized = false;
1926
double retry_interval = 10; /* 10s between trying a server and
1927
retrying the same server again */
1929
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1930
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1935
/* Lower any group privileges we might have, just to be safe */
1939
perror_plus("setgid");
1942
/* Lower user privileges (temporarily) */
1946
perror_plus("seteuid");
1954
struct argp_option options[] = {
1955
{ .name = "debug", .key = 128,
1956
.doc = "Debug mode", .group = 3 },
1957
{ .name = "connect", .key = 'c',
1958
.arg = "ADDRESS:PORT",
1959
.doc = "Connect directly to a specific Mandos server",
1961
{ .name = "interface", .key = 'i',
1963
.doc = "Network interface that will be used to search for"
1966
{ .name = "seckey", .key = 's',
1968
.doc = "OpenPGP secret key file base name",
1970
{ .name = "pubkey", .key = 'p',
1972
.doc = "OpenPGP public key file base name",
1974
{ .name = "dh-bits", .key = 129,
1976
.doc = "Bit length of the prime number used in the"
1977
" Diffie-Hellman key exchange",
1979
{ .name = "priority", .key = 130,
1981
.doc = "GnuTLS priority string for the TLS handshake",
1983
{ .name = "delay", .key = 131,
1985
.doc = "Maximum delay to wait for interface startup",
1987
{ .name = "retry", .key = 132,
1989
.doc = "Retry interval used when denied by the Mandos server",
1991
{ .name = "network-hook-dir", .key = 133,
1993
.doc = "Directory where network hooks are located",
1996
* These reproduce what we would get without ARGP_NO_HELP
1998
{ .name = "help", .key = '?',
1999
.doc = "Give this help list", .group = -1 },
2000
{ .name = "usage", .key = -3,
2001
.doc = "Give a short usage message", .group = -1 },
2002
{ .name = "version", .key = 'V',
2003
.doc = "Print program version", .group = -1 },
2007
error_t parse_opt(int key, char *arg,
2008
struct argp_state *state){
2011
case 128: /* --debug */
2014
case 'c': /* --connect */
2017
case 'i': /* --interface */
2018
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2021
argp_error(state, "%s", strerror(ret_errno));
2024
case 's': /* --seckey */
2027
case 'p': /* --pubkey */
2030
case 129: /* --dh-bits */
2032
tmpmax = strtoimax(arg, &tmp, 10);
2033
if(errno != 0 or tmp == arg or *tmp != '\0'
2034
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2035
argp_error(state, "Bad number of DH bits");
2037
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2039
case 130: /* --priority */
2042
case 131: /* --delay */
2044
delay = strtof(arg, &tmp);
2045
if(errno != 0 or tmp == arg or *tmp != '\0'){
2046
argp_error(state, "Bad delay");
2048
case 132: /* --retry */
2050
retry_interval = strtod(arg, &tmp);
2051
if(errno != 0 or tmp == arg or *tmp != '\0'
2052
or (retry_interval * 1000) > INT_MAX
2053
or retry_interval < 0){
2054
argp_error(state, "Bad retry interval");
2057
case 133: /* --network-hook-dir */
2061
* These reproduce what we would get without ARGP_NO_HELP
2063
case '?': /* --help */
2064
argp_state_help(state, state->out_stream,
2065
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2066
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2067
case -3: /* --usage */
2068
argp_state_help(state, state->out_stream,
2069
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2070
case 'V': /* --version */
2071
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2072
exit(argp_err_exit_status);
2075
return ARGP_ERR_UNKNOWN;
2080
struct argp argp = { .options = options, .parser = parse_opt,
2082
.doc = "Mandos client -- Get and decrypt"
2083
" passwords from a Mandos server" };
2084
ret = argp_parse(&argp, argc, argv,
2085
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2092
perror_plus("argp_parse");
2093
exitcode = EX_OSERR;
2096
exitcode = EX_USAGE;
2102
/* Work around Debian bug #633582:
2103
<http://bugs.debian.org/633582> */
2105
/* Re-raise privileges */
2106
ret_errno = raise_privileges();
2109
perror_plus("Failed to raise privileges");
2113
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2114
int seckey_fd = open(seckey, O_RDONLY);
2115
if(seckey_fd == -1){
2116
perror_plus("open");
2118
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2120
perror_plus("fstat");
2122
if(S_ISREG(st.st_mode)
2123
and st.st_uid == 0 and st.st_gid == 0){
2124
ret = fchown(seckey_fd, uid, gid);
2126
perror_plus("fchown");
2130
TEMP_FAILURE_RETRY(close(seckey_fd));
2134
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2135
int pubkey_fd = open(pubkey, O_RDONLY);
2136
if(pubkey_fd == -1){
2137
perror_plus("open");
2139
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2141
perror_plus("fstat");
2143
if(S_ISREG(st.st_mode)
2144
and st.st_uid == 0 and st.st_gid == 0){
2145
ret = fchown(pubkey_fd, uid, gid);
2147
perror_plus("fchown");
2151
TEMP_FAILURE_RETRY(close(pubkey_fd));
2155
/* Lower privileges */
2156
ret_errno = lower_privileges();
2159
perror_plus("Failed to lower privileges");
2164
/* Remove invalid interface names (except "none") */
2166
char *interface = NULL;
2167
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2169
if(strcmp(interface, "none") != 0
2170
and if_nametoindex(interface) == 0){
2171
if(interface[0] != '\0'){
2172
fprintf_plus(stderr, "Not using nonexisting interface"
2173
" \"%s\"\n", interface);
2175
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2181
/* Run network hooks */
2183
if(mc.interfaces != NULL){
2184
interfaces_hooks = malloc(mc.interfaces_size);
2185
if(interfaces_hooks == NULL){
2186
perror_plus("malloc");
2189
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2190
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2192
run_network_hooks("start", interfaces_hooks != NULL ?
2193
interfaces_hooks : "", delay);
2197
avahi_set_log_function(empty_log);
2200
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2201
from the signal handler */
2202
/* Initialize the pseudo-RNG for Avahi */
2203
srand((unsigned int) time(NULL));
2204
simple_poll = avahi_simple_poll_new();
2205
if(simple_poll == NULL){
2206
fprintf_plus(stderr,
2207
"Avahi: Failed to create simple poll object.\n");
2208
exitcode = EX_UNAVAILABLE;
2212
sigemptyset(&sigterm_action.sa_mask);
2213
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2215
perror_plus("sigaddset");
2216
exitcode = EX_OSERR;
2219
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2221
perror_plus("sigaddset");
2222
exitcode = EX_OSERR;
2225
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2227
perror_plus("sigaddset");
2228
exitcode = EX_OSERR;
2231
/* Need to check if the handler is SIG_IGN before handling:
2232
| [[info:libc:Initial Signal Actions]] |
2233
| [[info:libc:Basic Signal Handling]] |
2235
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2237
perror_plus("sigaction");
2240
if(old_sigterm_action.sa_handler != SIG_IGN){
2241
ret = sigaction(SIGINT, &sigterm_action, NULL);
2243
perror_plus("sigaction");
2244
exitcode = EX_OSERR;
2248
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2250
perror_plus("sigaction");
2253
if(old_sigterm_action.sa_handler != SIG_IGN){
2254
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2256
perror_plus("sigaction");
2257
exitcode = EX_OSERR;
2261
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2263
perror_plus("sigaction");
2266
if(old_sigterm_action.sa_handler != SIG_IGN){
2267
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2269
perror_plus("sigaction");
2270
exitcode = EX_OSERR;
2275
/* If no interfaces were specified, make a list */
2276
if(mc.interfaces == NULL){
2277
struct dirent **direntries = NULL;
2278
/* Look for any good interfaces */
2279
ret = scandir(sys_class_net, &direntries, good_interface,
2282
/* Add all found interfaces to interfaces list */
2283
for(int i = 0; i < ret; ++i){
2284
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2285
direntries[i]->d_name);
2288
perror_plus("argz_add");
2289
free(direntries[i]);
2293
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2294
direntries[i]->d_name);
2296
free(direntries[i]);
2303
fprintf_plus(stderr, "Could not find a network interface\n");
2304
exitcode = EXIT_FAILURE;
2309
/* Bring up interfaces which are down, and remove any "none"s */
2311
char *interface = NULL;
2312
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2314
/* If interface name is "none", stop bringing up interfaces.
2315
Also remove all instances of "none" from the list */
2316
if(strcmp(interface, "none") == 0){
2317
argz_delete(&mc.interfaces, &mc.interfaces_size,
2320
while((interface = argz_next(mc.interfaces,
2321
mc.interfaces_size, interface))){
2322
if(strcmp(interface, "none") == 0){
2323
argz_delete(&mc.interfaces, &mc.interfaces_size,
2330
bool interface_was_up = interface_is_up(interface);
2331
errno = bring_up_interface(interface, delay);
2332
if(not interface_was_up){
2334
perror_plus("Failed to bring up interface");
2336
errno = argz_add(&interfaces_to_take_down,
2337
&interfaces_to_take_down_size,
2340
perror_plus("argz_add");
2345
if(debug and (interfaces_to_take_down == NULL)){
2346
fprintf_plus(stderr, "No interfaces were brought up\n");
2350
/* If we only got one interface, explicitly use only that one */
2351
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);
2353
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2356
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2363
ret = init_gnutls_global(pubkey, seckey, &mc);
2365
fprintf_plus(stderr, "init_gnutls_global failed\n");
2366
exitcode = EX_UNAVAILABLE;
2369
gnutls_initialized = true;
2376
/* Try /run/tmp before /tmp */
2377
tempdir = mkdtemp(run_tempdir);
2378
if(tempdir == NULL and errno == ENOENT){
2380
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2381
run_tempdir, old_tempdir);
2383
tempdir = mkdtemp(old_tempdir);
2385
if(tempdir == NULL){
2386
perror_plus("mkdtemp");
2394
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2395
fprintf_plus(stderr, "init_gpgme failed\n");
2396
exitcode = EX_UNAVAILABLE;
2399
gpgme_initialized = true;
2406
if(connect_to != NULL){
2407
/* Connect directly, do not use Zeroconf */
2408
/* (Mainly meant for debugging) */
2409
char *address = strrchr(connect_to, ':');
2411
if(address == NULL){
2412
fprintf_plus(stderr, "No colon in address\n");
2413
exitcode = EX_USAGE;
2423
tmpmax = strtoimax(address+1, &tmp, 10);
2424
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2425
or tmpmax != (in_port_t)tmpmax){
2426
fprintf_plus(stderr, "Bad port number\n");
2427
exitcode = EX_USAGE;
2435
port = (in_port_t)tmpmax;
2437
/* Colon in address indicates IPv6 */
2439
if(strchr(connect_to, ':') != NULL){
2441
/* Accept [] around IPv6 address - see RFC 5952 */
2442
if(connect_to[0] == '[' and address[-1] == ']')
2450
address = connect_to;
2456
while(not quit_now){
2457
ret = start_mandos_communication(address, port, if_index, af,
2459
if(quit_now or ret == 0){
2463
fprintf_plus(stderr, "Retrying in %d seconds\n",
2464
(int)retry_interval);
2466
sleep((unsigned int)retry_interval);
2470
exitcode = EXIT_SUCCESS;
2481
AvahiServerConfig config;
2482
/* Do not publish any local Zeroconf records */
2483
avahi_server_config_init(&config);
2484
config.publish_hinfo = 0;
2485
config.publish_addresses = 0;
2486
config.publish_workstation = 0;
2487
config.publish_domain = 0;
2489
/* Allocate a new server */
2490
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2491
&config, NULL, NULL, &ret_errno);
2493
/* Free the Avahi configuration data */
2494
avahi_server_config_free(&config);
2497
/* Check if creating the Avahi server object succeeded */
2498
if(mc.server == NULL){
2499
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2500
avahi_strerror(ret_errno));
2501
exitcode = EX_UNAVAILABLE;
2509
/* Create the Avahi service browser */
2510
sb = avahi_s_service_browser_new(mc.server, if_index,
2511
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2512
NULL, 0, browse_callback,
2515
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2516
avahi_strerror(avahi_server_errno(mc.server)));
2517
exitcode = EX_UNAVAILABLE;
2525
/* Run the main loop */
2528
fprintf_plus(stderr, "Starting Avahi loop search\n");
2531
ret = avahi_loop_with_timeout(simple_poll,
2532
(int)(retry_interval * 1000), &mc);
2534
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2535
(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){
2541
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2544
/* Cleanup things */
2545
free(mc.interfaces);
2548
avahi_s_service_browser_free(sb);
2550
if(mc.server != NULL)
2551
avahi_server_free(mc.server);
2553
if(simple_poll != NULL)
2554
avahi_simple_poll_free(simple_poll);
2556
if(gnutls_initialized){
2557
gnutls_certificate_free_credentials(mc.cred);
2558
gnutls_global_deinit();
2559
gnutls_dh_params_deinit(mc.dh_params);
2562
if(gpgme_initialized){
2563
gpgme_release(mc.ctx);
2566
/* Cleans up the circular linked list of Mandos servers the client
2568
if(mc.current_server != NULL){
2569
mc.current_server->prev->next = NULL;
2570
while(mc.current_server != NULL){
2571
server *next = mc.current_server->next;
2573
#pragma GCC diagnostic push
2574
#pragma GCC diagnostic ignored "-Wcast-qual"
2576
free((char *)(mc.current_server->ip));
2578
#pragma GCC diagnostic pop
2580
free(mc.current_server);
2581
mc.current_server = next;
2585
/* Re-raise privileges */
2587
ret_errno = raise_privileges();
2590
perror_plus("Failed to raise privileges");
2593
/* Run network hooks */
2594
run_network_hooks("stop", interfaces_hooks != NULL ?
2595
interfaces_hooks : "", delay);
2597
/* Take down the network interfaces which were brought up */
2599
char *interface = NULL;
2600
while((interface=argz_next(interfaces_to_take_down,
2601
interfaces_to_take_down_size,
2603
ret_errno = take_down_interface(interface);
2606
perror_plus("Failed to take down interface");
2609
if(debug and (interfaces_to_take_down == NULL)){
2610
fprintf_plus(stderr, "No interfaces needed to be taken"
2616
ret_errno = lower_privileges_permanently();
2619
perror_plus("Failed to lower privileges permanently");
2623
free(interfaces_to_take_down);
2624
free(interfaces_hooks);
2626
/* Removes the GPGME temp directory and all files inside */
2627
if(tempdir != NULL){
2628
struct dirent **direntries = NULL;
2629
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2631
if(tempdir_fd == -1){
2632
perror_plus("open");
2635
#if __GLIBC_PREREQ(2, 15)
2636
int numentries = scandirat(tempdir_fd, ".", &direntries,
2637
notdotentries, alphasort);
2638
#else /* not __GLIBC_PREREQ(2, 15) */
2639
int numentries = scandir(tempdir, &direntries, notdotentries,
2641
#endif /* not __GLIBC_PREREQ(2, 15) */
2642
#else /* not __GLIBC__ */
2643
int numentries = scandir(tempdir, &direntries, notdotentries,
2645
#endif /* not __GLIBC__ */
2646
if(numentries >= 0){
2647
for(int i = 0; i < numentries; i++){
2648
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2650
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2651
" \"%s\", 0): %s\n", tempdir,
2652
direntries[i]->d_name, strerror(errno));
2654
free(direntries[i]);
2657
/* need to clean even if 0 because man page doesn't specify */
2659
if(numentries == -1){
2660
perror_plus("scandir");
2662
ret = rmdir(tempdir);
2663
if(ret == -1 and errno != ENOENT){
2664
perror_plus("rmdir");
2667
TEMP_FAILURE_RETRY(close(tempdir_fd));
2672
sigemptyset(&old_sigterm_action.sa_mask);
2673
old_sigterm_action.sa_handler = SIG_DFL;
2674
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2675
&old_sigterm_action,
2678
perror_plus("sigaction");
2681
ret = raise(signal_received);
2682
} while(ret != 0 and errno == EINTR);
2684
perror_plus("raise");
2687
TEMP_FAILURE_RETRY(pause());