812
1160
case AVAHI_BROWSER_ALL_FOR_NOW:
813
1161
case AVAHI_BROWSER_CACHE_EXHAUSTED:
815
fprintf(stderr, "No Mandos server found, still searching...\n");
1163
fprintf_plus(stderr, "No Mandos server found, still"
1170
/* Signal handler that stops main loop after SIGTERM */
1171
static void handle_sigterm(int sig){
1176
signal_received = sig;
1177
int old_errno = errno;
1178
/* set main loop to exit */
1179
if(simple_poll != NULL){
1180
avahi_simple_poll_quit(simple_poll);
1185
__attribute__((nonnull, warn_unused_result))
1186
bool get_flags(const char *ifname, struct ifreq *ifr){
1190
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1193
perror_plus("socket");
1197
strcpy(ifr->ifr_name, ifname);
1198
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1202
perror_plus("ioctl SIOCGIFFLAGS");
1210
__attribute__((nonnull, warn_unused_result))
1211
bool good_flags(const char *ifname, const struct ifreq *ifr){
1213
/* Reject the loopback device */
1214
if(ifr->ifr_flags & IFF_LOOPBACK){
1216
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1221
/* Accept point-to-point devices only if connect_to is specified */
1222
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1224
fprintf_plus(stderr, "Accepting point-to-point interface"
1225
" \"%s\"\n", ifname);
1229
/* Otherwise, reject non-broadcast-capable devices */
1230
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1232
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1233
" \"%s\"\n", ifname);
1237
/* Reject non-ARP interfaces (including dummy interfaces) */
1238
if(ifr->ifr_flags & IFF_NOARP){
1240
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1246
/* Accept this device */
1248
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1254
* This function determines if a directory entry in /sys/class/net
1255
* corresponds to an acceptable network device.
1256
* (This function is passed to scandir(3) as a filter function.)
1258
__attribute__((nonnull, warn_unused_result))
1259
int good_interface(const struct dirent *if_entry){
1260
if(if_entry->d_name[0] == '.'){
1265
if(not get_flags(if_entry->d_name, &ifr)){
1267
fprintf_plus(stderr, "Failed to get flags for interface "
1268
"\"%s\"\n", if_entry->d_name);
1273
if(not good_flags(if_entry->d_name, &ifr)){
1280
* This function determines if a network interface is up.
1282
__attribute__((nonnull, warn_unused_result))
1283
bool interface_is_up(const char *interface){
1285
if(not get_flags(interface, &ifr)){
1287
fprintf_plus(stderr, "Failed to get flags for interface "
1288
"\"%s\"\n", interface);
1293
return (bool)(ifr.ifr_flags & IFF_UP);
1297
* This function determines if a network interface is running
1299
__attribute__((nonnull, warn_unused_result))
1300
bool interface_is_running(const char *interface){
1302
if(not get_flags(interface, &ifr)){
1304
fprintf_plus(stderr, "Failed to get flags for interface "
1305
"\"%s\"\n", interface);
1310
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1313
__attribute__((nonnull, pure, warn_unused_result))
1314
int notdotentries(const struct dirent *direntry){
1315
/* Skip "." and ".." */
1316
if(direntry->d_name[0] == '.'
1317
and (direntry->d_name[1] == '\0'
1318
or (direntry->d_name[1] == '.'
1319
and direntry->d_name[2] == '\0'))){
1325
/* Is this directory entry a runnable program? */
1326
__attribute__((nonnull, warn_unused_result))
1327
int runnable_hook(const struct dirent *direntry){
1332
if((direntry->d_name)[0] == '\0'){
1337
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1338
"abcdefghijklmnopqrstuvwxyz"
1341
if((direntry->d_name)[sret] != '\0'){
1342
/* Contains non-allowed characters */
1344
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1350
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1353
perror_plus("Could not stat hook");
1357
if(not (S_ISREG(st.st_mode))){
1358
/* Not a regular file */
1360
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1365
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1366
/* Not executable */
1368
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1374
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1380
__attribute__((nonnull, warn_unused_result))
1381
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1382
mandos_context *mc){
1384
struct timespec now;
1385
struct timespec waited_time;
1386
intmax_t block_time;
1389
if(mc->current_server == NULL){
1391
fprintf_plus(stderr, "Wait until first server is found."
1394
ret = avahi_simple_poll_iterate(s, -1);
1397
fprintf_plus(stderr, "Check current_server if we should run"
1400
/* the current time */
1401
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1403
perror_plus("clock_gettime");
1406
/* Calculating in ms how long time between now and server
1407
who we visted longest time ago. Now - last seen. */
1408
waited_time.tv_sec = (now.tv_sec
1409
- mc->current_server->last_seen.tv_sec);
1410
waited_time.tv_nsec = (now.tv_nsec
1411
- mc->current_server->last_seen.tv_nsec);
1412
/* total time is 10s/10,000ms.
1413
Converting to s from ms by dividing by 1,000,
1414
and ns to ms by dividing by 1,000,000. */
1415
block_time = ((retry_interval
1416
- ((intmax_t)waited_time.tv_sec * 1000))
1417
- ((intmax_t)waited_time.tv_nsec / 1000000));
1420
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1424
if(block_time <= 0){
1425
ret = start_mandos_communication(mc->current_server->ip,
1426
mc->current_server->port,
1427
mc->current_server->if_index,
1428
mc->current_server->af, mc);
1430
avahi_simple_poll_quit(s);
1433
ret = clock_gettime(CLOCK_MONOTONIC,
1434
&mc->current_server->last_seen);
1436
perror_plus("clock_gettime");
1439
mc->current_server = mc->current_server->next;
1440
block_time = 0; /* Call avahi to find new Mandos
1441
servers, but don't block */
1444
ret = avahi_simple_poll_iterate(s, (int)block_time);
1447
if(ret > 0 or errno != EINTR){
1448
return (ret != 1) ? ret : 0;
1454
/* Set effective uid to 0, return errno */
1455
__attribute__((warn_unused_result))
1456
error_t raise_privileges(void){
1457
error_t old_errno = errno;
1458
error_t ret_errno = 0;
1459
if(seteuid(0) == -1){
1461
perror_plus("seteuid");
1467
/* Set effective and real user ID to 0. Return errno. */
1468
__attribute__((warn_unused_result))
1469
error_t raise_privileges_permanently(void){
1470
error_t old_errno = errno;
1471
error_t ret_errno = raise_privileges();
1476
if(setuid(0) == -1){
1478
perror_plus("seteuid");
1484
/* Set effective user ID to unprivileged saved user ID */
1485
__attribute__((warn_unused_result))
1486
error_t lower_privileges(void){
1487
error_t old_errno = errno;
1488
error_t ret_errno = 0;
1489
if(seteuid(uid) == -1){
1491
perror_plus("seteuid");
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){
1504
perror_plus("setuid");
1510
__attribute__((nonnull))
1511
void run_network_hooks(const char *mode, const char *interface,
1513
struct dirent **direntries;
1514
if(hookdir_fd == -1){
1515
hookdir_fd = open(hookdir, O_RDONLY);
1516
if(hookdir_fd == -1){
1517
if(errno == ENOENT){
1519
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1520
" found\n", hookdir);
1523
perror_plus("open");
1529
#if __GLIBC_PREREQ(2, 15)
1530
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1531
runnable_hook, alphasort);
1532
#else /* not __GLIBC_PREREQ(2, 15) */
1533
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1535
#endif /* not __GLIBC_PREREQ(2, 15) */
1536
#else /* not __GLIBC__ */
1537
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1539
#endif /* not __GLIBC__ */
1541
perror_plus("scandir");
1544
struct dirent *direntry;
1546
int devnull = open("/dev/null", O_RDONLY);
1547
for(int i = 0; i < numhooks; i++){
1548
direntry = direntries[i];
1550
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1553
pid_t hook_pid = fork();
1556
/* Raise privileges */
1557
if(raise_privileges_permanently() != 0){
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",
1673
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1674
perror_plus("close");
1681
__attribute__((nonnull, warn_unused_result))
1682
error_t bring_up_interface(const char *const interface,
1684
error_t old_errno = errno;
1686
struct ifreq network;
1687
unsigned int if_index = if_nametoindex(interface);
1689
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1699
if(not interface_is_up(interface)){
1700
error_t ret_errno = 0, ioctl_errno = 0;
1701
if(not get_flags(interface, &network)){
1703
fprintf_plus(stderr, "Failed to get flags for interface "
1704
"\"%s\"\n", interface);
1708
network.ifr_flags |= IFF_UP; /* set flag */
1710
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1713
perror_plus("socket");
1719
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1721
perror_plus("close");
1728
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1732
/* Raise privileges */
1733
ret_errno = raise_privileges();
1735
perror_plus("Failed to raise privileges");
1740
bool restore_loglevel = false;
1742
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1743
messages about the network interface to mess up the prompt */
1744
ret_linux = klogctl(8, NULL, 5);
1745
if(ret_linux == -1){
1746
perror_plus("klogctl");
1748
restore_loglevel = true;
1751
#endif /* __linux__ */
1752
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1753
ioctl_errno = errno;
1755
if(restore_loglevel){
1756
ret_linux = klogctl(7, NULL, 0);
1757
if(ret_linux == -1){
1758
perror_plus("klogctl");
1761
#endif /* __linux__ */
1763
/* If raise_privileges() succeeded above */
1765
/* Lower privileges */
1766
ret_errno = lower_privileges();
1769
perror_plus("Failed to lower privileges");
1773
/* Close the socket */
1774
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1776
perror_plus("close");
1779
if(ret_setflags == -1){
1780
errno = ioctl_errno;
1781
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1786
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1790
/* Sleep checking until interface is running.
1791
Check every 0.25s, up to total time of delay */
1792
for(int i=0; i < delay * 4; i++){
1793
if(interface_is_running(interface)){
1796
struct timespec sleeptime = { .tv_nsec = 250000000 };
1797
ret = nanosleep(&sleeptime, NULL);
1798
if(ret == -1 and errno != EINTR){
1799
perror_plus("nanosleep");
1807
__attribute__((nonnull, warn_unused_result))
1808
error_t take_down_interface(const char *const interface){
1809
error_t old_errno = errno;
1810
struct ifreq network;
1811
unsigned int if_index = if_nametoindex(interface);
1813
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1817
if(interface_is_up(interface)){
1818
error_t ret_errno = 0, ioctl_errno = 0;
1819
if(not get_flags(interface, &network) and debug){
1821
fprintf_plus(stderr, "Failed to get flags for interface "
1822
"\"%s\"\n", interface);
1826
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1828
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1831
perror_plus("socket");
1837
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1841
/* Raise privileges */
1842
ret_errno = raise_privileges();
1844
perror_plus("Failed to raise privileges");
1847
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1848
ioctl_errno = errno;
1850
/* If raise_privileges() succeeded above */
1852
/* Lower privileges */
1853
ret_errno = lower_privileges();
1856
perror_plus("Failed to lower privileges");
1860
/* Close the socket */
1861
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1863
perror_plus("close");
1866
if(ret_setflags == -1){
1867
errno = ioctl_errno;
1868
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1873
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
821
1881
int main(int argc, char *argv[]){
822
AvahiSServiceBrowser *sb = NULL;
827
int exitcode = EXIT_SUCCESS;
828
const char *interface = "eth0";
829
struct ifreq network;
833
char *connect_to = NULL;
834
char tempdir[] = "/tmp/mandosXXXXXX";
835
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
836
const char *seckey = PATHDIR "/" SECKEY;
837
const char *pubkey = PATHDIR "/" PUBKEY;
839
mandos_context mc = { .simple_poll = NULL, .server = NULL,
840
.dh_bits = 1024, .priority = "SECURE256"
841
":!CTYPE-X.509:+CTYPE-OPENPGP" };
842
bool gnutls_initialized = false;
843
bool gpgme_initialized = false;
846
struct argp_option options[] = {
847
{ .name = "debug", .key = 128,
848
.doc = "Debug mode", .group = 3 },
849
{ .name = "connect", .key = 'c',
850
.arg = "ADDRESS:PORT",
851
.doc = "Connect directly to a specific Mandos server",
853
{ .name = "interface", .key = 'i',
855
.doc = "Interface that will be used to search for Mandos"
858
{ .name = "seckey", .key = 's',
860
.doc = "OpenPGP secret key file base name",
862
{ .name = "pubkey", .key = 'p',
864
.doc = "OpenPGP public key file base name",
866
{ .name = "dh-bits", .key = 129,
868
.doc = "Bit length of the prime number used in the"
869
" Diffie-Hellman key exchange",
871
{ .name = "priority", .key = 130,
873
.doc = "GnuTLS priority string for the TLS handshake",
878
error_t parse_opt(int key, char *arg,
879
struct argp_state *state) {
881
case 128: /* --debug */
884
case 'c': /* --connect */
887
case 'i': /* --interface */
890
case 's': /* --seckey */
893
case 'p': /* --pubkey */
896
case 129: /* --dh-bits */
897
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
898
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
899
or arg[numchars] != '\0'){
900
fprintf(stderr, "Bad number of DH bits\n");
903
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
905
case 130: /* --priority */
913
return ARGP_ERR_UNKNOWN;
918
struct argp argp = { .options = options, .parser = parse_opt,
920
.doc = "Mandos client -- Get and decrypt"
921
" passwords from a Mandos server" };
922
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
923
if(ret == ARGP_ERR_UNKNOWN){
924
fprintf(stderr, "Unknown error while parsing arguments\n");
925
exitcode = EXIT_FAILURE;
930
/* If the interface is down, bring it up */
932
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
935
exitcode = EXIT_FAILURE;
938
strcpy(network.ifr_name, interface);
939
ret = ioctl(sd, SIOCGIFFLAGS, &network);
941
perror("ioctl SIOCGIFFLAGS");
942
exitcode = EXIT_FAILURE;
945
if((network.ifr_flags & IFF_UP) == 0){
946
network.ifr_flags |= IFF_UP;
947
ret = ioctl(sd, SIOCSIFFLAGS, &network);
949
perror("ioctl SIOCSIFFLAGS");
950
exitcode = EXIT_FAILURE;
954
ret = (int)TEMP_FAILURE_RETRY(close(sd));
973
ret = init_gnutls_global(&mc, pubkey, seckey);
975
fprintf(stderr, "init_gnutls_global failed\n");
976
exitcode = EXIT_FAILURE;
979
gnutls_initialized = true;
982
if(mkdtemp(tempdir) == NULL){
988
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
989
fprintf(stderr, "init_gpgme failed\n");
990
exitcode = EXIT_FAILURE;
993
gpgme_initialized = true;
996
if_index = (AvahiIfIndex) if_nametoindex(interface);
998
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1002
if(connect_to != NULL){
1003
/* Connect directly, do not use Zeroconf */
1004
/* (Mainly meant for debugging) */
1005
char *address = strrchr(connect_to, ':');
1006
if(address == NULL){
1007
fprintf(stderr, "No colon in address\n");
1008
exitcode = EXIT_FAILURE;
1012
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1013
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1014
or address[numchars+1] != '\0'){
1015
fprintf(stderr, "Bad port number\n");
1016
exitcode = EXIT_FAILURE;
1019
port = (uint16_t)tmpmax;
1021
address = connect_to;
1022
ret = start_mandos_communication(address, port, if_index, &mc);
1024
exitcode = EXIT_FAILURE;
1026
exitcode = EXIT_SUCCESS;
1032
avahi_set_log_function(empty_log);
1035
/* Initialize the pseudo-RNG for Avahi */
1036
srand((unsigned int) time(NULL));
1038
/* Allocate main Avahi loop object */
1039
mc.simple_poll = avahi_simple_poll_new();
1040
if(mc.simple_poll == NULL) {
1041
fprintf(stderr, "Avahi: Failed to create simple poll"
1043
exitcode = EXIT_FAILURE;
1048
AvahiServerConfig config;
1049
/* Do not publish any local Zeroconf records */
1050
avahi_server_config_init(&config);
1051
config.publish_hinfo = 0;
1052
config.publish_addresses = 0;
1053
config.publish_workstation = 0;
1054
config.publish_domain = 0;
1056
/* Allocate a new server */
1057
mc.server = avahi_server_new(avahi_simple_poll_get
1058
(mc.simple_poll), &config, NULL,
1061
/* Free the Avahi configuration data */
1062
avahi_server_config_free(&config);
1065
/* Check if creating the Avahi server object succeeded */
1066
if(mc.server == NULL) {
1067
fprintf(stderr, "Failed to create Avahi server: %s\n",
1068
avahi_strerror(error));
1069
exitcode = EXIT_FAILURE;
1073
/* Create the Avahi service browser */
1074
sb = avahi_s_service_browser_new(mc.server, if_index,
1076
"_mandos._tcp", NULL, 0,
1077
browse_callback, &mc);
1079
fprintf(stderr, "Failed to create service browser: %s\n",
1080
avahi_strerror(avahi_server_errno(mc.server)));
1081
exitcode = EXIT_FAILURE;
1085
/* Run the main loop */
1882
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1883
.priority = "SECURE256:!CTYPE-X.509:"
1884
"+CTYPE-OPENPGP", .current_server = NULL,
1885
.interfaces = NULL, .interfaces_size = 0 };
1886
AvahiSServiceBrowser *sb = NULL;
1891
int exitcode = EXIT_SUCCESS;
1892
char *interfaces_to_take_down = NULL;
1893
size_t interfaces_to_take_down_size = 0;
1894
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1895
char old_tempdir[] = "/tmp/mandosXXXXXX";
1896
char *tempdir = NULL;
1897
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1898
const char *seckey = PATHDIR "/" SECKEY;
1899
const char *pubkey = PATHDIR "/" PUBKEY;
1900
char *interfaces_hooks = NULL;
1902
bool gnutls_initialized = false;
1903
bool gpgme_initialized = false;
1905
double retry_interval = 10; /* 10s between trying a server and
1906
retrying the same server again */
1908
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1909
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1914
/* Lower any group privileges we might have, just to be safe */
1918
perror_plus("setgid");
1921
/* Lower user privileges (temporarily) */
1925
perror_plus("seteuid");
1933
struct argp_option options[] = {
1934
{ .name = "debug", .key = 128,
1935
.doc = "Debug mode", .group = 3 },
1936
{ .name = "connect", .key = 'c',
1937
.arg = "ADDRESS:PORT",
1938
.doc = "Connect directly to a specific Mandos server",
1940
{ .name = "interface", .key = 'i',
1942
.doc = "Network interface that will be used to search for"
1945
{ .name = "seckey", .key = 's',
1947
.doc = "OpenPGP secret key file base name",
1949
{ .name = "pubkey", .key = 'p',
1951
.doc = "OpenPGP public key file base name",
1953
{ .name = "dh-bits", .key = 129,
1955
.doc = "Bit length of the prime number used in the"
1956
" Diffie-Hellman key exchange",
1958
{ .name = "priority", .key = 130,
1960
.doc = "GnuTLS priority string for the TLS handshake",
1962
{ .name = "delay", .key = 131,
1964
.doc = "Maximum delay to wait for interface startup",
1966
{ .name = "retry", .key = 132,
1968
.doc = "Retry interval used when denied by the Mandos server",
1970
{ .name = "network-hook-dir", .key = 133,
1972
.doc = "Directory where network hooks are located",
1975
* These reproduce what we would get without ARGP_NO_HELP
1977
{ .name = "help", .key = '?',
1978
.doc = "Give this help list", .group = -1 },
1979
{ .name = "usage", .key = -3,
1980
.doc = "Give a short usage message", .group = -1 },
1981
{ .name = "version", .key = 'V',
1982
.doc = "Print program version", .group = -1 },
1986
error_t parse_opt(int key, char *arg,
1987
struct argp_state *state){
1990
case 128: /* --debug */
1993
case 'c': /* --connect */
1996
case 'i': /* --interface */
1997
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2000
argp_error(state, "%s", strerror(ret_errno));
2003
case 's': /* --seckey */
2006
case 'p': /* --pubkey */
2009
case 129: /* --dh-bits */
2011
tmpmax = strtoimax(arg, &tmp, 10);
2012
if(errno != 0 or tmp == arg or *tmp != '\0'
2013
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2014
argp_error(state, "Bad number of DH bits");
2016
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2018
case 130: /* --priority */
2021
case 131: /* --delay */
2023
delay = strtof(arg, &tmp);
2024
if(errno != 0 or tmp == arg or *tmp != '\0'){
2025
argp_error(state, "Bad delay");
2027
case 132: /* --retry */
2029
retry_interval = strtod(arg, &tmp);
2030
if(errno != 0 or tmp == arg or *tmp != '\0'
2031
or (retry_interval * 1000) > INT_MAX
2032
or retry_interval < 0){
2033
argp_error(state, "Bad retry interval");
2036
case 133: /* --network-hook-dir */
2040
* These reproduce what we would get without ARGP_NO_HELP
2042
case '?': /* --help */
2043
argp_state_help(state, state->out_stream,
2044
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2045
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2046
case -3: /* --usage */
2047
argp_state_help(state, state->out_stream,
2048
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2049
case 'V': /* --version */
2050
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2051
exit(argp_err_exit_status);
2054
return ARGP_ERR_UNKNOWN;
2059
struct argp argp = { .options = options, .parser = parse_opt,
2061
.doc = "Mandos client -- Get and decrypt"
2062
" passwords from a Mandos server" };
2063
ret = argp_parse(&argp, argc, argv,
2064
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2071
perror_plus("argp_parse");
2072
exitcode = EX_OSERR;
2075
exitcode = EX_USAGE;
2081
/* Work around Debian bug #633582:
2082
<http://bugs.debian.org/633582> */
2084
/* Re-raise privileges */
2085
ret_errno = raise_privileges();
2088
perror_plus("Failed to raise privileges");
2092
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2093
int seckey_fd = open(seckey, O_RDONLY);
2094
if(seckey_fd == -1){
2095
perror_plus("open");
2097
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2099
perror_plus("fstat");
2101
if(S_ISREG(st.st_mode)
2102
and st.st_uid == 0 and st.st_gid == 0){
2103
ret = fchown(seckey_fd, uid, gid);
2105
perror_plus("fchown");
2109
TEMP_FAILURE_RETRY(close(seckey_fd));
2113
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2114
int pubkey_fd = open(pubkey, O_RDONLY);
2115
if(pubkey_fd == -1){
2116
perror_plus("open");
2118
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_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(pubkey_fd, uid, gid);
2126
perror_plus("fchown");
2130
TEMP_FAILURE_RETRY(close(pubkey_fd));
2134
/* Lower privileges */
2135
ret_errno = lower_privileges();
2138
perror_plus("Failed to lower privileges");
2143
/* Remove invalid interface names (except "none") */
2145
char *interface = NULL;
2146
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2148
if(strcmp(interface, "none") != 0
2149
and if_nametoindex(interface) == 0){
2150
if(interface[0] != '\0'){
2151
fprintf_plus(stderr, "Not using nonexisting interface"
2152
" \"%s\"\n", interface);
2154
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2160
/* Run network hooks */
2162
if(mc.interfaces != NULL){
2163
interfaces_hooks = malloc(mc.interfaces_size);
2164
if(interfaces_hooks == NULL){
2165
perror_plus("malloc");
2168
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2169
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2171
run_network_hooks("start", interfaces_hooks != NULL ?
2172
interfaces_hooks : "", delay);
2176
avahi_set_log_function(empty_log);
2179
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2180
from the signal handler */
2181
/* Initialize the pseudo-RNG for Avahi */
2182
srand((unsigned int) time(NULL));
2183
simple_poll = avahi_simple_poll_new();
2184
if(simple_poll == NULL){
2185
fprintf_plus(stderr,
2186
"Avahi: Failed to create simple poll object.\n");
2187
exitcode = EX_UNAVAILABLE;
2191
sigemptyset(&sigterm_action.sa_mask);
2192
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2194
perror_plus("sigaddset");
2195
exitcode = EX_OSERR;
2198
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2200
perror_plus("sigaddset");
2201
exitcode = EX_OSERR;
2204
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2206
perror_plus("sigaddset");
2207
exitcode = EX_OSERR;
2210
/* Need to check if the handler is SIG_IGN before handling:
2211
| [[info:libc:Initial Signal Actions]] |
2212
| [[info:libc:Basic Signal Handling]] |
2214
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2216
perror_plus("sigaction");
2219
if(old_sigterm_action.sa_handler != SIG_IGN){
2220
ret = sigaction(SIGINT, &sigterm_action, NULL);
2222
perror_plus("sigaction");
2223
exitcode = EX_OSERR;
2227
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2229
perror_plus("sigaction");
2232
if(old_sigterm_action.sa_handler != SIG_IGN){
2233
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2235
perror_plus("sigaction");
2236
exitcode = EX_OSERR;
2240
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2242
perror_plus("sigaction");
2245
if(old_sigterm_action.sa_handler != SIG_IGN){
2246
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2248
perror_plus("sigaction");
2249
exitcode = EX_OSERR;
2254
/* If no interfaces were specified, make a list */
2255
if(mc.interfaces == NULL){
2256
struct dirent **direntries = NULL;
2257
/* Look for any good interfaces */
2258
ret = scandir(sys_class_net, &direntries, good_interface,
2261
/* Add all found interfaces to interfaces list */
2262
for(int i = 0; i < ret; ++i){
2263
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2264
direntries[i]->d_name);
2267
perror_plus("argz_add");
2271
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2272
direntries[i]->d_name);
2278
fprintf_plus(stderr, "Could not find a network interface\n");
2279
exitcode = EXIT_FAILURE;
2284
/* Bring up interfaces which are down, and remove any "none"s */
2286
char *interface = NULL;
2287
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2289
/* If interface name is "none", stop bringing up interfaces.
2290
Also remove all instances of "none" from the list */
2291
if(strcmp(interface, "none") == 0){
2292
argz_delete(&mc.interfaces, &mc.interfaces_size,
2295
while((interface = argz_next(mc.interfaces,
2296
mc.interfaces_size, interface))){
2297
if(strcmp(interface, "none") == 0){
2298
argz_delete(&mc.interfaces, &mc.interfaces_size,
2305
bool interface_was_up = interface_is_up(interface);
2306
errno = bring_up_interface(interface, delay);
2307
if(not interface_was_up){
2309
perror_plus("Failed to bring up interface");
2311
errno = argz_add(&interfaces_to_take_down,
2312
&interfaces_to_take_down_size,
2315
perror_plus("argz_add");
2320
if(debug and (interfaces_to_take_down == NULL)){
2321
fprintf_plus(stderr, "No interfaces were brought up\n");
2325
/* If we only got one interface, explicitly use only that one */
2326
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
1088
fprintf(stderr, "Starting Avahi loop search\n");
1091
avahi_simple_poll_loop(mc.simple_poll);
2328
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2331
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2338
ret = init_gnutls_global(pubkey, seckey, &mc);
2340
fprintf_plus(stderr, "init_gnutls_global failed\n");
2341
exitcode = EX_UNAVAILABLE;
2344
gnutls_initialized = true;
2351
/* Try /run/tmp before /tmp */
2352
tempdir = mkdtemp(run_tempdir);
2353
if(tempdir == NULL and errno == ENOENT){
2355
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2356
run_tempdir, old_tempdir);
2358
tempdir = mkdtemp(old_tempdir);
2360
if(tempdir == NULL){
2361
perror_plus("mkdtemp");
2369
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2370
fprintf_plus(stderr, "init_gpgme failed\n");
2371
exitcode = EX_UNAVAILABLE;
2374
gpgme_initialized = true;
2381
if(connect_to != NULL){
2382
/* Connect directly, do not use Zeroconf */
2383
/* (Mainly meant for debugging) */
2384
char *address = strrchr(connect_to, ':');
2386
if(address == NULL){
2387
fprintf_plus(stderr, "No colon in address\n");
2388
exitcode = EX_USAGE;
2398
tmpmax = strtoimax(address+1, &tmp, 10);
2399
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2400
or tmpmax != (in_port_t)tmpmax){
2401
fprintf_plus(stderr, "Bad port number\n");
2402
exitcode = EX_USAGE;
2410
port = (in_port_t)tmpmax;
2412
/* Colon in address indicates IPv6 */
2414
if(strchr(connect_to, ':') != NULL){
2416
/* Accept [] around IPv6 address - see RFC 5952 */
2417
if(connect_to[0] == '[' and address[-1] == ']')
2425
address = connect_to;
2431
while(not quit_now){
2432
ret = start_mandos_communication(address, port, if_index, af,
2434
if(quit_now or ret == 0){
2438
fprintf_plus(stderr, "Retrying in %d seconds\n",
2439
(int)retry_interval);
2441
sleep((unsigned int)retry_interval);
2445
exitcode = EXIT_SUCCESS;
2456
AvahiServerConfig config;
2457
/* Do not publish any local Zeroconf records */
2458
avahi_server_config_init(&config);
2459
config.publish_hinfo = 0;
2460
config.publish_addresses = 0;
2461
config.publish_workstation = 0;
2462
config.publish_domain = 0;
2464
/* Allocate a new server */
2465
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2466
&config, NULL, NULL, &ret_errno);
2468
/* Free the Avahi configuration data */
2469
avahi_server_config_free(&config);
2472
/* Check if creating the Avahi server object succeeded */
2473
if(mc.server == NULL){
2474
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2475
avahi_strerror(ret_errno));
2476
exitcode = EX_UNAVAILABLE;
2484
/* Create the Avahi service browser */
2485
sb = avahi_s_service_browser_new(mc.server, if_index,
2486
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2487
NULL, 0, browse_callback,
2490
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2491
avahi_strerror(avahi_server_errno(mc.server)));
2492
exitcode = EX_UNAVAILABLE;
2500
/* Run the main loop */
2503
fprintf_plus(stderr, "Starting Avahi loop search\n");
2506
ret = avahi_loop_with_timeout(simple_poll,
2507
(int)(retry_interval * 1000), &mc);
2509
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2510
(ret == 0) ? "successfully" : "with error");
1096
fprintf(stderr, "%s exiting\n", argv[0]);
1099
/* Cleanup things */
1101
avahi_s_service_browser_free(sb);
1103
if(mc.server != NULL)
1104
avahi_server_free(mc.server);
1106
if(mc.simple_poll != NULL)
1107
avahi_simple_poll_free(mc.simple_poll);
1109
if(gnutls_initialized){
1110
gnutls_certificate_free_credentials(mc.cred);
1111
gnutls_global_deinit();
1112
gnutls_dh_params_deinit(mc.dh_params);
1115
if(gpgme_initialized){
1116
gpgme_release(mc.ctx);
1119
/* Removes the temp directory used by GPGME */
1120
if(tempdir[0] != '\0'){
1122
struct dirent *direntry;
1123
d = opendir(tempdir);
1125
if(errno != ENOENT){
1130
direntry = readdir(d);
1131
if(direntry == NULL){
1134
/* Skip "." and ".." */
1135
if(direntry->d_name[0] == '.'
1136
and (direntry->d_name[1] == '\0'
1137
or (direntry->d_name[1] == '.'
1138
and direntry->d_name[2] == '\0'))){
1141
char *fullname = NULL;
1142
ret = asprintf(&fullname, "%s/%s", tempdir,
1148
ret = remove(fullname);
2516
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2519
/* Cleanup things */
2520
free(mc.interfaces);
2523
avahi_s_service_browser_free(sb);
2525
if(mc.server != NULL)
2526
avahi_server_free(mc.server);
2528
if(simple_poll != NULL)
2529
avahi_simple_poll_free(simple_poll);
2531
if(gnutls_initialized){
2532
gnutls_certificate_free_credentials(mc.cred);
2533
gnutls_global_deinit();
2534
gnutls_dh_params_deinit(mc.dh_params);
2537
if(gpgme_initialized){
2538
gpgme_release(mc.ctx);
2541
/* Cleans up the circular linked list of Mandos servers the client
2543
if(mc.current_server != NULL){
2544
mc.current_server->prev->next = NULL;
2545
while(mc.current_server != NULL){
2546
server *next = mc.current_server->next;
2547
free(mc.current_server);
2548
mc.current_server = next;
2552
/* Re-raise privileges */
2554
ret_errno = raise_privileges();
2556
perror_plus("Failed to raise privileges");
2559
/* Run network hooks */
2560
run_network_hooks("stop", interfaces_hooks != NULL ?
2561
interfaces_hooks : "", delay);
2563
/* Take down the network interfaces which were brought up */
2565
char *interface = NULL;
2566
while((interface=argz_next(interfaces_to_take_down,
2567
interfaces_to_take_down_size,
2569
ret_errno = take_down_interface(interface);
2572
perror_plus("Failed to take down interface");
2575
if(debug and (interfaces_to_take_down == NULL)){
2576
fprintf_plus(stderr, "No interfaces needed to be taken"
2582
ret_errno = lower_privileges_permanently();
2584
perror_plus("Failed to lower privileges permanently");
2588
free(interfaces_to_take_down);
2589
free(interfaces_hooks);
2591
/* Removes the GPGME temp directory and all files inside */
2592
if(tempdir != NULL){
2593
struct dirent **direntries = NULL;
2594
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2596
if(tempdir_fd == -1){
2597
perror_plus("open");
2600
#if __GLIBC_PREREQ(2, 15)
2601
int numentries = scandirat(tempdir_fd, ".", &direntries,
2602
notdotentries, alphasort);
2603
#else /* not __GLIBC_PREREQ(2, 15) */
2604
int numentries = scandir(tempdir, &direntries, notdotentries,
2606
#endif /* not __GLIBC_PREREQ(2, 15) */
2607
#else /* not __GLIBC__ */
2608
int numentries = scandir(tempdir, &direntries, notdotentries,
2610
#endif /* not __GLIBC__ */
2612
for(int i = 0; i < numentries; i++){
2613
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
1150
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2615
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2616
" \"%s\", 0): %s\n", tempdir,
2617
direntries[i]->d_name, strerror(errno));
1157
ret = rmdir(tempdir);
1158
if(ret == -1 and errno != ENOENT){
2621
/* need to clean even if 0 because man page doesn't specify */
2623
if(numentries == -1){
2624
perror_plus("scandir");
2626
ret = rmdir(tempdir);
2627
if(ret == -1 and errno != ENOENT){
2628
perror_plus("rmdir");
2631
TEMP_FAILURE_RETRY(close(tempdir_fd));
2636
sigemptyset(&old_sigterm_action.sa_mask);
2637
old_sigterm_action.sa_handler = SIG_DFL;
2638
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2639
&old_sigterm_action,
2642
perror_plus("sigaction");
2645
ret = raise(signal_received);
2646
} while(ret != 0 and errno == EINTR);
2648
perror_plus("raise");
2651
TEMP_FAILURE_RETRY(pause());