811
1159
case AVAHI_BROWSER_ALL_FOR_NOW:
812
1160
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
fprintf(stderr, "No Mandos server found, still searching...\n");
1162
fprintf_plus(stderr, "No Mandos server found, still"
1169
/* Signal handler that stops main loop after SIGTERM */
1170
static void handle_sigterm(int sig){
1175
signal_received = sig;
1176
int old_errno = errno;
1177
/* set main loop to exit */
1178
if(simple_poll != NULL){
1179
avahi_simple_poll_quit(simple_poll);
1184
__attribute__((nonnull, warn_unused_result))
1185
bool get_flags(const char *ifname, struct ifreq *ifr){
1189
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1192
perror_plus("socket");
1196
strcpy(ifr->ifr_name, ifname);
1197
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1201
perror_plus("ioctl SIOCGIFFLAGS");
1209
__attribute__((nonnull, warn_unused_result))
1210
bool good_flags(const char *ifname, const struct ifreq *ifr){
1212
/* Reject the loopback device */
1213
if(ifr->ifr_flags & IFF_LOOPBACK){
1215
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1220
/* Accept point-to-point devices only if connect_to is specified */
1221
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1223
fprintf_plus(stderr, "Accepting point-to-point interface"
1224
" \"%s\"\n", ifname);
1228
/* Otherwise, reject non-broadcast-capable devices */
1229
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1231
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1232
" \"%s\"\n", ifname);
1236
/* Reject non-ARP interfaces (including dummy interfaces) */
1237
if(ifr->ifr_flags & IFF_NOARP){
1239
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1245
/* Accept this device */
1247
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1253
* This function determines if a directory entry in /sys/class/net
1254
* corresponds to an acceptable network device.
1255
* (This function is passed to scandir(3) as a filter function.)
1257
__attribute__((nonnull, warn_unused_result))
1258
int good_interface(const struct dirent *if_entry){
1259
if(if_entry->d_name[0] == '.'){
1264
if(not get_flags(if_entry->d_name, &ifr)){
1266
fprintf_plus(stderr, "Failed to get flags for interface "
1267
"\"%s\"\n", if_entry->d_name);
1272
if(not good_flags(if_entry->d_name, &ifr)){
1279
* This function determines if a network interface is up.
1281
__attribute__((nonnull, warn_unused_result))
1282
bool interface_is_up(const char *interface){
1284
if(not get_flags(interface, &ifr)){
1286
fprintf_plus(stderr, "Failed to get flags for interface "
1287
"\"%s\"\n", interface);
1292
return (bool)(ifr.ifr_flags & IFF_UP);
1296
* This function determines if a network interface is running
1298
__attribute__((nonnull, warn_unused_result))
1299
bool interface_is_running(const char *interface){
1301
if(not get_flags(interface, &ifr)){
1303
fprintf_plus(stderr, "Failed to get flags for interface "
1304
"\"%s\"\n", interface);
1309
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1312
__attribute__((nonnull, pure, warn_unused_result))
1313
int notdotentries(const struct dirent *direntry){
1314
/* Skip "." and ".." */
1315
if(direntry->d_name[0] == '.'
1316
and (direntry->d_name[1] == '\0'
1317
or (direntry->d_name[1] == '.'
1318
and direntry->d_name[2] == '\0'))){
1324
/* Is this directory entry a runnable program? */
1325
__attribute__((nonnull, warn_unused_result))
1326
int runnable_hook(const struct dirent *direntry){
1331
if((direntry->d_name)[0] == '\0'){
1336
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1337
"abcdefghijklmnopqrstuvwxyz"
1340
if((direntry->d_name)[sret] != '\0'){
1341
/* Contains non-allowed characters */
1343
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1349
char *fullname = NULL;
1350
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1352
perror_plus("asprintf");
1356
ret = stat(fullname, &st);
1359
perror_plus("Could not stat hook");
1364
if(not (S_ISREG(st.st_mode))){
1365
/* Not a regular file */
1367
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1372
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1373
/* Not executable */
1375
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1381
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1387
__attribute__((nonnull, warn_unused_result))
1388
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1389
mandos_context *mc){
1391
struct timespec now;
1392
struct timespec waited_time;
1393
intmax_t block_time;
1396
if(mc->current_server == NULL){
1398
fprintf_plus(stderr, "Wait until first server is found."
1401
ret = avahi_simple_poll_iterate(s, -1);
1404
fprintf_plus(stderr, "Check current_server if we should run"
1407
/* the current time */
1408
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1410
perror_plus("clock_gettime");
1413
/* Calculating in ms how long time between now and server
1414
who we visted longest time ago. Now - last seen. */
1415
waited_time.tv_sec = (now.tv_sec
1416
- mc->current_server->last_seen.tv_sec);
1417
waited_time.tv_nsec = (now.tv_nsec
1418
- mc->current_server->last_seen.tv_nsec);
1419
/* total time is 10s/10,000ms.
1420
Converting to s from ms by dividing by 1,000,
1421
and ns to ms by dividing by 1,000,000. */
1422
block_time = ((retry_interval
1423
- ((intmax_t)waited_time.tv_sec * 1000))
1424
- ((intmax_t)waited_time.tv_nsec / 1000000));
1427
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1431
if(block_time <= 0){
1432
ret = start_mandos_communication(mc->current_server->ip,
1433
mc->current_server->port,
1434
mc->current_server->if_index,
1435
mc->current_server->af, mc);
1437
avahi_simple_poll_quit(s);
1440
ret = clock_gettime(CLOCK_MONOTONIC,
1441
&mc->current_server->last_seen);
1443
perror_plus("clock_gettime");
1446
mc->current_server = mc->current_server->next;
1447
block_time = 0; /* Call avahi to find new Mandos
1448
servers, but don't block */
1451
ret = avahi_simple_poll_iterate(s, (int)block_time);
1454
if(ret > 0 or errno != EINTR){
1455
return (ret != 1) ? ret : 0;
1461
/* Set effective uid to 0, return errno */
1462
__attribute__((warn_unused_result))
1463
error_t raise_privileges(void){
1464
error_t old_errno = errno;
1465
error_t ret_errno = 0;
1466
if(seteuid(0) == -1){
1468
perror_plus("seteuid");
1474
/* Set effective and real user ID to 0. Return errno. */
1475
__attribute__((warn_unused_result))
1476
error_t raise_privileges_permanently(void){
1477
error_t old_errno = errno;
1478
error_t ret_errno = raise_privileges();
1483
if(setuid(0) == -1){
1485
perror_plus("seteuid");
1491
/* Set effective user ID to unprivileged saved user ID */
1492
__attribute__((warn_unused_result))
1493
error_t lower_privileges(void){
1494
error_t old_errno = errno;
1495
error_t ret_errno = 0;
1496
if(seteuid(uid) == -1){
1498
perror_plus("seteuid");
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){
1511
perror_plus("setuid");
1519
* Based on the example in the GNU LibC manual chapter 13.13 "File
1520
* Descriptor Flags".
1521
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
1523
__attribute__((warn_unused_result))
1524
static int set_cloexec_flag(int fd){
1525
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
1526
/* If reading the flags failed, return error indication now. */
1530
/* Store modified flag word in the descriptor. */
1531
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
1534
#endif /* not O_CLOEXEC */
1536
__attribute__((nonnull))
1537
void run_network_hooks(const char *mode, const char *interface,
1539
struct dirent **direntries;
1540
if(hookdir_fd == -1){
1541
hookdir_fd = open(hookdir, O_RDONLY |
1544
#else /* not O_CLOEXEC */
1546
#endif /* not O_CLOEXEC */
1548
if(hookdir_fd == -1){
1549
if(errno == ENOENT){
1551
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1552
" found\n", hookdir);
1555
perror_plus("open");
1560
if(set_cloexec_flag(hookdir_fd) < 0){
1561
perror_plus("set_cloexec_flag");
1562
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1563
perror_plus("close");
1569
#endif /* not O_CLOEXEC */
1572
#if __GLIBC_PREREQ(2, 15)
1573
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1574
runnable_hook, alphasort);
1575
#else /* not __GLIBC_PREREQ(2, 15) */
1576
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1578
#endif /* not __GLIBC_PREREQ(2, 15) */
1579
#else /* not __GLIBC__ */
1580
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1582
#endif /* not __GLIBC__ */
1584
perror_plus("scandir");
1587
struct dirent *direntry;
1589
int devnull = open("/dev/null", O_RDONLY);
1590
for(int i = 0; i < numhooks; i++){
1591
direntry = direntries[i];
1592
char *fullname = NULL;
1593
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1595
perror_plus("asprintf");
1599
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1602
pid_t hook_pid = fork();
1605
/* Raise privileges */
1606
if(raise_privileges_permanently() != 0){
1607
perror_plus("Failed to raise privileges");
1614
perror_plus("setgid");
1617
/* Reset supplementary groups */
1619
ret = setgroups(0, NULL);
1621
perror_plus("setgroups");
1624
ret = dup2(devnull, STDIN_FILENO);
1626
perror_plus("dup2(devnull, STDIN_FILENO)");
1629
ret = close(devnull);
1631
perror_plus("close");
1634
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1636
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1639
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1641
perror_plus("setenv");
1644
ret = setenv("DEVICE", interface, 1);
1646
perror_plus("setenv");
1649
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1651
perror_plus("setenv");
1654
ret = setenv("MODE", mode, 1);
1656
perror_plus("setenv");
1660
ret = asprintf(&delaystring, "%f", (double)delay);
1662
perror_plus("asprintf");
1665
ret = setenv("DELAY", delaystring, 1);
1668
perror_plus("setenv");
1672
if(connect_to != NULL){
1673
ret = setenv("CONNECT", connect_to, 1);
1675
perror_plus("setenv");
1679
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1680
perror_plus("execl");
1681
_exit(EXIT_FAILURE);
1685
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1686
perror_plus("waitpid");
1690
if(WIFEXITED(status)){
1691
if(WEXITSTATUS(status) != 0){
1692
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1693
" with status %d\n", direntry->d_name,
1694
WEXITSTATUS(status));
1698
} else if(WIFSIGNALED(status)){
1699
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1700
" signal %d\n", direntry->d_name,
1705
fprintf_plus(stderr, "Warning: network hook \"%s\""
1706
" crashed\n", direntry->d_name);
1713
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1717
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1718
perror_plus("close");
1725
__attribute__((nonnull, warn_unused_result))
1726
error_t bring_up_interface(const char *const interface,
1728
error_t old_errno = errno;
1730
struct ifreq network;
1731
unsigned int if_index = if_nametoindex(interface);
1733
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1743
if(not interface_is_up(interface)){
1744
error_t ret_errno = 0, ioctl_errno = 0;
1745
if(not get_flags(interface, &network)){
1747
fprintf_plus(stderr, "Failed to get flags for interface "
1748
"\"%s\"\n", interface);
1752
network.ifr_flags |= IFF_UP; /* set flag */
1754
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1757
perror_plus("socket");
1763
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1765
perror_plus("close");
1772
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1776
/* Raise privileges */
1777
ret_errno = raise_privileges();
1779
perror_plus("Failed to raise privileges");
1784
bool restore_loglevel = false;
1786
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1787
messages about the network interface to mess up the prompt */
1788
ret_linux = klogctl(8, NULL, 5);
1789
if(ret_linux == -1){
1790
perror_plus("klogctl");
1792
restore_loglevel = true;
1795
#endif /* __linux__ */
1796
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1797
ioctl_errno = errno;
1799
if(restore_loglevel){
1800
ret_linux = klogctl(7, NULL, 0);
1801
if(ret_linux == -1){
1802
perror_plus("klogctl");
1805
#endif /* __linux__ */
1807
/* If raise_privileges() succeeded above */
1809
/* Lower privileges */
1810
ret_errno = lower_privileges();
1813
perror_plus("Failed to lower privileges");
1817
/* Close the socket */
1818
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1820
perror_plus("close");
1823
if(ret_setflags == -1){
1824
errno = ioctl_errno;
1825
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1830
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1834
/* Sleep checking until interface is running.
1835
Check every 0.25s, up to total time of delay */
1836
for(int i=0; i < delay * 4; i++){
1837
if(interface_is_running(interface)){
1840
struct timespec sleeptime = { .tv_nsec = 250000000 };
1841
ret = nanosleep(&sleeptime, NULL);
1842
if(ret == -1 and errno != EINTR){
1843
perror_plus("nanosleep");
1851
__attribute__((nonnull, warn_unused_result))
1852
error_t take_down_interface(const char *const interface){
1853
error_t old_errno = errno;
1854
struct ifreq network;
1855
unsigned int if_index = if_nametoindex(interface);
1857
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1861
if(interface_is_up(interface)){
1862
error_t ret_errno = 0, ioctl_errno = 0;
1863
if(not get_flags(interface, &network) and debug){
1865
fprintf_plus(stderr, "Failed to get flags for interface "
1866
"\"%s\"\n", interface);
1870
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1872
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1875
perror_plus("socket");
1881
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1885
/* Raise privileges */
1886
ret_errno = raise_privileges();
1888
perror_plus("Failed to raise privileges");
1891
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1892
ioctl_errno = errno;
1894
/* If raise_privileges() succeeded above */
1896
/* Lower privileges */
1897
ret_errno = lower_privileges();
1900
perror_plus("Failed to lower privileges");
1904
/* Close the socket */
1905
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1907
perror_plus("close");
1910
if(ret_setflags == -1){
1911
errno = ioctl_errno;
1912
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1917
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
820
1925
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_initalized = false;
842
bool gpgme_initalized = 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_initalized = true;
981
if(mkdtemp(tempdir) == NULL){
987
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
988
fprintf(stderr, "gpgme_initalized failed\n");
989
exitcode = EXIT_FAILURE;
992
gpgme_initalized = 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 */
1926
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1927
.priority = "SECURE256:!CTYPE-X.509:"
1928
"+CTYPE-OPENPGP", .current_server = NULL,
1929
.interfaces = NULL, .interfaces_size = 0 };
1930
AvahiSServiceBrowser *sb = NULL;
1935
int exitcode = EXIT_SUCCESS;
1936
char *interfaces_to_take_down = NULL;
1937
size_t interfaces_to_take_down_size = 0;
1938
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1939
char old_tempdir[] = "/tmp/mandosXXXXXX";
1940
char *tempdir = NULL;
1941
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1942
const char *seckey = PATHDIR "/" SECKEY;
1943
const char *pubkey = PATHDIR "/" PUBKEY;
1944
char *interfaces_hooks = NULL;
1946
bool gnutls_initialized = false;
1947
bool gpgme_initialized = false;
1949
double retry_interval = 10; /* 10s between trying a server and
1950
retrying the same server again */
1952
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1953
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1958
/* Lower any group privileges we might have, just to be safe */
1962
perror_plus("setgid");
1965
/* Lower user privileges (temporarily) */
1969
perror_plus("seteuid");
1977
struct argp_option options[] = {
1978
{ .name = "debug", .key = 128,
1979
.doc = "Debug mode", .group = 3 },
1980
{ .name = "connect", .key = 'c',
1981
.arg = "ADDRESS:PORT",
1982
.doc = "Connect directly to a specific Mandos server",
1984
{ .name = "interface", .key = 'i',
1986
.doc = "Network interface that will be used to search for"
1989
{ .name = "seckey", .key = 's',
1991
.doc = "OpenPGP secret key file base name",
1993
{ .name = "pubkey", .key = 'p',
1995
.doc = "OpenPGP public key file base name",
1997
{ .name = "dh-bits", .key = 129,
1999
.doc = "Bit length of the prime number used in the"
2000
" Diffie-Hellman key exchange",
2002
{ .name = "priority", .key = 130,
2004
.doc = "GnuTLS priority string for the TLS handshake",
2006
{ .name = "delay", .key = 131,
2008
.doc = "Maximum delay to wait for interface startup",
2010
{ .name = "retry", .key = 132,
2012
.doc = "Retry interval used when denied by the Mandos server",
2014
{ .name = "network-hook-dir", .key = 133,
2016
.doc = "Directory where network hooks are located",
2019
* These reproduce what we would get without ARGP_NO_HELP
2021
{ .name = "help", .key = '?',
2022
.doc = "Give this help list", .group = -1 },
2023
{ .name = "usage", .key = -3,
2024
.doc = "Give a short usage message", .group = -1 },
2025
{ .name = "version", .key = 'V',
2026
.doc = "Print program version", .group = -1 },
2030
error_t parse_opt(int key, char *arg,
2031
struct argp_state *state){
2034
case 128: /* --debug */
2037
case 'c': /* --connect */
2040
case 'i': /* --interface */
2041
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2044
argp_error(state, "%s", strerror(ret_errno));
2047
case 's': /* --seckey */
2050
case 'p': /* --pubkey */
2053
case 129: /* --dh-bits */
2055
tmpmax = strtoimax(arg, &tmp, 10);
2056
if(errno != 0 or tmp == arg or *tmp != '\0'
2057
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2058
argp_error(state, "Bad number of DH bits");
2060
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2062
case 130: /* --priority */
2065
case 131: /* --delay */
2067
delay = strtof(arg, &tmp);
2068
if(errno != 0 or tmp == arg or *tmp != '\0'){
2069
argp_error(state, "Bad delay");
2071
case 132: /* --retry */
2073
retry_interval = strtod(arg, &tmp);
2074
if(errno != 0 or tmp == arg or *tmp != '\0'
2075
or (retry_interval * 1000) > INT_MAX
2076
or retry_interval < 0){
2077
argp_error(state, "Bad retry interval");
2080
case 133: /* --network-hook-dir */
2084
* These reproduce what we would get without ARGP_NO_HELP
2086
case '?': /* --help */
2087
argp_state_help(state, state->out_stream,
2088
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2089
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2090
case -3: /* --usage */
2091
argp_state_help(state, state->out_stream,
2092
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2093
case 'V': /* --version */
2094
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2095
exit(argp_err_exit_status);
2098
return ARGP_ERR_UNKNOWN;
2103
struct argp argp = { .options = options, .parser = parse_opt,
2105
.doc = "Mandos client -- Get and decrypt"
2106
" passwords from a Mandos server" };
2107
ret = argp_parse(&argp, argc, argv,
2108
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2115
perror_plus("argp_parse");
2116
exitcode = EX_OSERR;
2119
exitcode = EX_USAGE;
2125
/* Work around Debian bug #633582:
2126
<http://bugs.debian.org/633582> */
2128
/* Re-raise privileges */
2129
ret_errno = raise_privileges();
2132
perror_plus("Failed to raise privileges");
2136
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2137
int seckey_fd = open(seckey, O_RDONLY);
2138
if(seckey_fd == -1){
2139
perror_plus("open");
2141
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2143
perror_plus("fstat");
2145
if(S_ISREG(st.st_mode)
2146
and st.st_uid == 0 and st.st_gid == 0){
2147
ret = fchown(seckey_fd, uid, gid);
2149
perror_plus("fchown");
2153
TEMP_FAILURE_RETRY(close(seckey_fd));
2157
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2158
int pubkey_fd = open(pubkey, O_RDONLY);
2159
if(pubkey_fd == -1){
2160
perror_plus("open");
2162
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2164
perror_plus("fstat");
2166
if(S_ISREG(st.st_mode)
2167
and st.st_uid == 0 and st.st_gid == 0){
2168
ret = fchown(pubkey_fd, uid, gid);
2170
perror_plus("fchown");
2174
TEMP_FAILURE_RETRY(close(pubkey_fd));
2178
/* Lower privileges */
2179
ret_errno = lower_privileges();
2182
perror_plus("Failed to lower privileges");
2187
/* Remove invalid interface names (except "none") */
2189
char *interface = NULL;
2190
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2192
if(strcmp(interface, "none") != 0
2193
and if_nametoindex(interface) == 0){
2194
if(interface[0] != '\0'){
2195
fprintf_plus(stderr, "Not using nonexisting interface"
2196
" \"%s\"\n", interface);
2198
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2204
/* Run network hooks */
2206
if(mc.interfaces != NULL){
2207
interfaces_hooks = malloc(mc.interfaces_size);
2208
if(interfaces_hooks == NULL){
2209
perror_plus("malloc");
2212
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2213
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2215
run_network_hooks("start", interfaces_hooks != NULL ?
2216
interfaces_hooks : "", delay);
2220
avahi_set_log_function(empty_log);
2223
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2224
from the signal handler */
2225
/* Initialize the pseudo-RNG for Avahi */
2226
srand((unsigned int) time(NULL));
2227
simple_poll = avahi_simple_poll_new();
2228
if(simple_poll == NULL){
2229
fprintf_plus(stderr,
2230
"Avahi: Failed to create simple poll object.\n");
2231
exitcode = EX_UNAVAILABLE;
2235
sigemptyset(&sigterm_action.sa_mask);
2236
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2238
perror_plus("sigaddset");
2239
exitcode = EX_OSERR;
2242
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2244
perror_plus("sigaddset");
2245
exitcode = EX_OSERR;
2248
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2250
perror_plus("sigaddset");
2251
exitcode = EX_OSERR;
2254
/* Need to check if the handler is SIG_IGN before handling:
2255
| [[info:libc:Initial Signal Actions]] |
2256
| [[info:libc:Basic Signal Handling]] |
2258
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2260
perror_plus("sigaction");
2263
if(old_sigterm_action.sa_handler != SIG_IGN){
2264
ret = sigaction(SIGINT, &sigterm_action, NULL);
2266
perror_plus("sigaction");
2267
exitcode = EX_OSERR;
2271
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2273
perror_plus("sigaction");
2276
if(old_sigterm_action.sa_handler != SIG_IGN){
2277
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2279
perror_plus("sigaction");
2280
exitcode = EX_OSERR;
2284
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2286
perror_plus("sigaction");
2289
if(old_sigterm_action.sa_handler != SIG_IGN){
2290
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2292
perror_plus("sigaction");
2293
exitcode = EX_OSERR;
2298
/* If no interfaces were specified, make a list */
2299
if(mc.interfaces == NULL){
2300
struct dirent **direntries;
2301
/* Look for any good interfaces */
2302
ret = scandir(sys_class_net, &direntries, good_interface,
2305
/* Add all found interfaces to interfaces list */
2306
for(int i = 0; i < ret; ++i){
2307
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2308
direntries[i]->d_name);
2311
perror_plus("argz_add");
2315
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2316
direntries[i]->d_name);
2322
fprintf_plus(stderr, "Could not find a network interface\n");
2323
exitcode = EXIT_FAILURE;
2328
/* Bring up interfaces which are down, and remove any "none"s */
2330
char *interface = NULL;
2331
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2333
/* If interface name is "none", stop bringing up interfaces.
2334
Also remove all instances of "none" from the list */
2335
if(strcmp(interface, "none") == 0){
2336
argz_delete(&mc.interfaces, &mc.interfaces_size,
2339
while((interface = argz_next(mc.interfaces,
2340
mc.interfaces_size, interface))){
2341
if(strcmp(interface, "none") == 0){
2342
argz_delete(&mc.interfaces, &mc.interfaces_size,
2349
bool interface_was_up = interface_is_up(interface);
2350
errno = bring_up_interface(interface, delay);
2351
if(not interface_was_up){
2353
perror_plus("Failed to bring up interface");
2355
errno = argz_add(&interfaces_to_take_down,
2356
&interfaces_to_take_down_size,
2359
perror_plus("argz_add");
2364
if(debug and (interfaces_to_take_down == NULL)){
2365
fprintf_plus(stderr, "No interfaces were brought up\n");
2369
/* If we only got one interface, explicitly use only that one */
2370
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);
2372
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2375
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2382
ret = init_gnutls_global(pubkey, seckey, &mc);
2384
fprintf_plus(stderr, "init_gnutls_global failed\n");
2385
exitcode = EX_UNAVAILABLE;
2388
gnutls_initialized = true;
2395
/* Try /run/tmp before /tmp */
2396
tempdir = mkdtemp(run_tempdir);
2397
if(tempdir == NULL and errno == ENOENT){
2399
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2400
run_tempdir, old_tempdir);
2402
tempdir = mkdtemp(old_tempdir);
2404
if(tempdir == NULL){
2405
perror_plus("mkdtemp");
2413
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2414
fprintf_plus(stderr, "init_gpgme failed\n");
2415
exitcode = EX_UNAVAILABLE;
2418
gpgme_initialized = true;
2425
if(connect_to != NULL){
2426
/* Connect directly, do not use Zeroconf */
2427
/* (Mainly meant for debugging) */
2428
char *address = strrchr(connect_to, ':');
2430
if(address == NULL){
2431
fprintf_plus(stderr, "No colon in address\n");
2432
exitcode = EX_USAGE;
2442
tmpmax = strtoimax(address+1, &tmp, 10);
2443
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2444
or tmpmax != (in_port_t)tmpmax){
2445
fprintf_plus(stderr, "Bad port number\n");
2446
exitcode = EX_USAGE;
2454
port = (in_port_t)tmpmax;
2456
/* Colon in address indicates IPv6 */
2458
if(strchr(connect_to, ':') != NULL){
2460
/* Accept [] around IPv6 address - see RFC 5952 */
2461
if(connect_to[0] == '[' and address[-1] == ']')
2469
address = connect_to;
2475
while(not quit_now){
2476
ret = start_mandos_communication(address, port, if_index, af,
2478
if(quit_now or ret == 0){
2482
fprintf_plus(stderr, "Retrying in %d seconds\n",
2483
(int)retry_interval);
2485
sleep((unsigned int)retry_interval);
2489
exitcode = EXIT_SUCCESS;
2500
AvahiServerConfig config;
2501
/* Do not publish any local Zeroconf records */
2502
avahi_server_config_init(&config);
2503
config.publish_hinfo = 0;
2504
config.publish_addresses = 0;
2505
config.publish_workstation = 0;
2506
config.publish_domain = 0;
2508
/* Allocate a new server */
2509
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2510
&config, NULL, NULL, &ret_errno);
2512
/* Free the Avahi configuration data */
2513
avahi_server_config_free(&config);
2516
/* Check if creating the Avahi server object succeeded */
2517
if(mc.server == NULL){
2518
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2519
avahi_strerror(ret_errno));
2520
exitcode = EX_UNAVAILABLE;
2528
/* Create the Avahi service browser */
2529
sb = avahi_s_service_browser_new(mc.server, if_index,
2530
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2531
NULL, 0, browse_callback,
2534
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2535
avahi_strerror(avahi_server_errno(mc.server)));
2536
exitcode = EX_UNAVAILABLE;
2544
/* Run the main loop */
2547
fprintf_plus(stderr, "Starting Avahi loop search\n");
2550
ret = avahi_loop_with_timeout(simple_poll,
2551
(int)(retry_interval * 1000), &mc);
2553
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2554
(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_initalized){
1109
gnutls_certificate_free_credentials(mc.cred);
1110
gnutls_global_deinit();
1111
gnutls_dh_params_deinit(mc.dh_params);
1114
if(gpgme_initalized){
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){
2560
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2563
/* Cleanup things */
2564
free(mc.interfaces);
2567
avahi_s_service_browser_free(sb);
2569
if(mc.server != NULL)
2570
avahi_server_free(mc.server);
2572
if(simple_poll != NULL)
2573
avahi_simple_poll_free(simple_poll);
2575
if(gnutls_initialized){
2576
gnutls_certificate_free_credentials(mc.cred);
2577
gnutls_global_deinit();
2578
gnutls_dh_params_deinit(mc.dh_params);
2581
if(gpgme_initialized){
2582
gpgme_release(mc.ctx);
2585
/* Cleans up the circular linked list of Mandos servers the client
2587
if(mc.current_server != NULL){
2588
mc.current_server->prev->next = NULL;
2589
while(mc.current_server != NULL){
2590
server *next = mc.current_server->next;
2591
free(mc.current_server);
2592
mc.current_server = next;
2596
/* Re-raise privileges */
2598
ret_errno = raise_privileges();
2600
perror_plus("Failed to raise privileges");
2603
/* Run network hooks */
2604
run_network_hooks("stop", interfaces_hooks != NULL ?
2605
interfaces_hooks : "", delay);
2607
/* Take down the network interfaces which were brought up */
2609
char *interface = NULL;
2610
while((interface=argz_next(interfaces_to_take_down,
2611
interfaces_to_take_down_size,
2613
ret_errno = take_down_interface(interface);
2616
perror_plus("Failed to take down interface");
2619
if(debug and (interfaces_to_take_down == NULL)){
2620
fprintf_plus(stderr, "No interfaces needed to be taken"
2626
ret_errno = lower_privileges_permanently();
2628
perror_plus("Failed to lower privileges permanently");
2632
free(interfaces_to_take_down);
2633
free(interfaces_hooks);
2635
/* Removes the GPGME temp directory and all files inside */
2636
if(tempdir != NULL){
2637
struct dirent **direntries = NULL;
2638
struct dirent *direntry = NULL;
2639
int numentries = scandir(tempdir, &direntries, notdotentries,
2642
for(int i = 0; i < numentries; i++){
2643
direntry = direntries[i];
2644
char *fullname = NULL;
2645
ret = asprintf(&fullname, "%s/%s", tempdir,
2648
perror_plus("asprintf");
2651
ret = remove(fullname);
2653
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2660
/* need to clean even if 0 because man page doesn't specify */
2662
if(numentries == -1){
2663
perror_plus("scandir");
2665
ret = rmdir(tempdir);
2666
if(ret == -1 and errno != ENOENT){
2667
perror_plus("rmdir");
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());