1158
812
case AVAHI_BROWSER_ALL_FOR_NOW:
1159
813
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1161
fprintf_plus(stderr, "No Mandos server found, still"
815
fprintf(stderr, "No Mandos server found, still searching...\n");
1168
/* Signal handler that stops main loop after SIGTERM */
1169
static void handle_sigterm(int sig){
1174
signal_received = sig;
1175
int old_errno = errno;
1176
/* set main loop to exit */
1177
if(simple_poll != NULL){
1178
avahi_simple_poll_quit(simple_poll);
1183
__attribute__((nonnull, warn_unused_result))
1184
bool get_flags(const char *ifname, struct ifreq *ifr){
1188
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1191
perror_plus("socket");
1195
strcpy(ifr->ifr_name, ifname);
1196
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1200
perror_plus("ioctl SIOCGIFFLAGS");
1208
__attribute__((nonnull, warn_unused_result))
1209
bool good_flags(const char *ifname, const struct ifreq *ifr){
1211
/* Reject the loopback device */
1212
if(ifr->ifr_flags & IFF_LOOPBACK){
1214
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1219
/* Accept point-to-point devices only if connect_to is specified */
1220
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1222
fprintf_plus(stderr, "Accepting point-to-point interface"
1223
" \"%s\"\n", ifname);
1227
/* Otherwise, reject non-broadcast-capable devices */
1228
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1230
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1231
" \"%s\"\n", ifname);
1235
/* Reject non-ARP interfaces (including dummy interfaces) */
1236
if(ifr->ifr_flags & IFF_NOARP){
1238
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1244
/* Accept this device */
1246
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1252
* This function determines if a directory entry in /sys/class/net
1253
* corresponds to an acceptable network device.
1254
* (This function is passed to scandir(3) as a filter function.)
1256
__attribute__((nonnull, warn_unused_result))
1257
int good_interface(const struct dirent *if_entry){
1258
if(if_entry->d_name[0] == '.'){
1263
if(not get_flags(if_entry->d_name, &ifr)){
1265
fprintf_plus(stderr, "Failed to get flags for interface "
1266
"\"%s\"\n", if_entry->d_name);
1271
if(not good_flags(if_entry->d_name, &ifr)){
1278
* This function determines if a network interface is up.
1280
__attribute__((nonnull, warn_unused_result))
1281
bool interface_is_up(const char *interface){
1283
if(not get_flags(interface, &ifr)){
1285
fprintf_plus(stderr, "Failed to get flags for interface "
1286
"\"%s\"\n", interface);
1291
return (bool)(ifr.ifr_flags & IFF_UP);
1295
* This function determines if a network interface is running
1297
__attribute__((nonnull, warn_unused_result))
1298
bool interface_is_running(const char *interface){
1300
if(not get_flags(interface, &ifr)){
1302
fprintf_plus(stderr, "Failed to get flags for interface "
1303
"\"%s\"\n", interface);
1308
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1311
__attribute__((nonnull, pure, warn_unused_result))
1312
int notdotentries(const struct dirent *direntry){
1313
/* Skip "." and ".." */
1314
if(direntry->d_name[0] == '.'
1315
and (direntry->d_name[1] == '\0'
1316
or (direntry->d_name[1] == '.'
1317
and direntry->d_name[2] == '\0'))){
1323
/* Is this directory entry a runnable program? */
1324
__attribute__((nonnull, warn_unused_result))
1325
int runnable_hook(const struct dirent *direntry){
1330
if((direntry->d_name)[0] == '\0'){
1335
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1336
"abcdefghijklmnopqrstuvwxyz"
1339
if((direntry->d_name)[sret] != '\0'){
1340
/* Contains non-allowed characters */
1342
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1348
char *fullname = NULL;
1349
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1351
perror_plus("asprintf");
1355
ret = stat(fullname, &st);
1358
perror_plus("Could not stat hook");
1362
if(not (S_ISREG(st.st_mode))){
1363
/* Not a regular file */
1365
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1370
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1371
/* Not executable */
1373
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1379
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1385
__attribute__((nonnull, warn_unused_result))
1386
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1387
mandos_context *mc){
1389
struct timespec now;
1390
struct timespec waited_time;
1391
intmax_t block_time;
1394
if(mc->current_server == NULL){
1396
fprintf_plus(stderr, "Wait until first server is found."
1399
ret = avahi_simple_poll_iterate(s, -1);
1402
fprintf_plus(stderr, "Check current_server if we should run"
1405
/* the current time */
1406
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1408
perror_plus("clock_gettime");
1411
/* Calculating in ms how long time between now and server
1412
who we visted longest time ago. Now - last seen. */
1413
waited_time.tv_sec = (now.tv_sec
1414
- mc->current_server->last_seen.tv_sec);
1415
waited_time.tv_nsec = (now.tv_nsec
1416
- mc->current_server->last_seen.tv_nsec);
1417
/* total time is 10s/10,000ms.
1418
Converting to s from ms by dividing by 1,000,
1419
and ns to ms by dividing by 1,000,000. */
1420
block_time = ((retry_interval
1421
- ((intmax_t)waited_time.tv_sec * 1000))
1422
- ((intmax_t)waited_time.tv_nsec / 1000000));
1425
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1429
if(block_time <= 0){
1430
ret = start_mandos_communication(mc->current_server->ip,
1431
mc->current_server->port,
1432
mc->current_server->if_index,
1433
mc->current_server->af, mc);
1435
avahi_simple_poll_quit(s);
1438
ret = clock_gettime(CLOCK_MONOTONIC,
1439
&mc->current_server->last_seen);
1441
perror_plus("clock_gettime");
1444
mc->current_server = mc->current_server->next;
1445
block_time = 0; /* Call avahi to find new Mandos
1446
servers, but don't block */
1449
ret = avahi_simple_poll_iterate(s, (int)block_time);
1452
if(ret > 0 or errno != EINTR){
1453
return (ret != 1) ? ret : 0;
1459
/* Set effective uid to 0, return errno */
1460
__attribute__((warn_unused_result))
1461
error_t raise_privileges(void){
1462
error_t old_errno = errno;
1463
error_t ret_errno = 0;
1464
if(seteuid(0) == -1){
1466
perror_plus("seteuid");
1472
/* Set effective and real user ID to 0. Return errno. */
1473
__attribute__((warn_unused_result))
1474
error_t raise_privileges_permanently(void){
1475
error_t old_errno = errno;
1476
error_t ret_errno = raise_privileges();
1481
if(setuid(0) == -1){
1483
perror_plus("seteuid");
1489
/* Set effective user ID to unprivileged saved user ID */
1490
__attribute__((warn_unused_result))
1491
error_t lower_privileges(void){
1492
error_t old_errno = errno;
1493
error_t ret_errno = 0;
1494
if(seteuid(uid) == -1){
1496
perror_plus("seteuid");
1502
/* Lower privileges permanently */
1503
__attribute__((warn_unused_result))
1504
error_t lower_privileges_permanently(void){
1505
error_t old_errno = errno;
1506
error_t ret_errno = 0;
1507
if(setuid(uid) == -1){
1509
perror_plus("setuid");
1515
__attribute__((nonnull))
1516
void run_network_hooks(const char *mode, const char *interface,
1518
struct dirent **direntries;
1519
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1522
if(errno == ENOENT){
1524
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1525
" found\n", hookdir);
1528
perror_plus("scandir");
1531
struct dirent *direntry;
821
int main(int argc, char *argv[]){
822
AvahiSServiceBrowser *sb = NULL;
1533
int devnull = open("/dev/null", O_RDONLY);
1534
for(int i = 0; i < numhooks; i++){
1535
direntry = direntries[i];
1536
char *fullname = NULL;
1537
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
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_initalized = false;
843
bool gpgme_initalized = false;
847
struct argp_option options[] = {
848
{ .name = "debug", .key = 128,
849
.doc = "Debug mode", .group = 3 },
850
{ .name = "connect", .key = 'c',
851
.arg = "ADDRESS:PORT",
852
.doc = "Connect directly to a specific Mandos server",
854
{ .name = "interface", .key = 'i',
856
.doc = "Interface that will be used to search for Mandos"
859
{ .name = "seckey", .key = 's',
861
.doc = "OpenPGP secret key file base name",
863
{ .name = "pubkey", .key = 'p',
865
.doc = "OpenPGP public key file base name",
867
{ .name = "dh-bits", .key = 129,
869
.doc = "Bit length of the prime number used in the"
870
" Diffie-Hellman key exchange",
872
{ .name = "priority", .key = 130,
874
.doc = "GnuTLS priority string for the TLS handshake",
876
{ .name = "delay", .key = 131,
878
.doc = "Maximum delay to wait for interface startup",
883
error_t parse_opt(int key, char *arg,
884
struct argp_state *state) {
886
case 128: /* --debug */
889
case 'c': /* --connect */
892
case 'i': /* --interface */
895
case 's': /* --seckey */
898
case 'p': /* --pubkey */
901
case 129: /* --dh-bits */
902
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
903
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
904
or arg[numchars] != '\0'){
905
fprintf(stderr, "Bad number of DH bits\n");
908
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
910
case 130: /* --priority */
913
case 131: /* --delay */
914
ret = sscanf(arg, "%lf%n", &delay, &numchars);
915
if(ret < 1 or arg[numchars] != '\0'){
916
fprintf(stderr, "Bad delay\n");
925
return ARGP_ERR_UNKNOWN;
930
struct argp argp = { .options = options, .parser = parse_opt,
932
.doc = "Mandos client -- Get and decrypt"
933
" passwords from a Mandos server" };
934
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
935
if(ret == ARGP_ERR_UNKNOWN){
936
fprintf(stderr, "Unknown error while parsing arguments\n");
937
exitcode = EXIT_FAILURE;
942
/* If the interface is down, bring it up */
944
// Lower kernel loglevel to KERN_NOTICE to avoid
945
// KERN_INFO messages to mess up the prompt
946
ret = klogctl(8, NULL, 5);
951
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
954
exitcode = EXIT_FAILURE;
955
ret = klogctl(7, NULL, 0);
961
strcpy(network.ifr_name, interface);
962
ret = ioctl(sd, SIOCGIFFLAGS, &network);
964
perror("ioctl SIOCGIFFLAGS");
965
ret = klogctl(7, NULL, 0);
969
exitcode = EXIT_FAILURE;
972
if((network.ifr_flags & IFF_UP) == 0){
973
network.ifr_flags |= IFF_UP;
974
ret = ioctl(sd, SIOCSIFFLAGS, &network);
976
perror("ioctl SIOCSIFFLAGS");
977
exitcode = EXIT_FAILURE;
978
ret = klogctl(7, NULL, 0);
985
// sleep checking until interface is running
986
for(int i=0; i < delay * 4; i++){
987
ret = ioctl(sd, SIOCGIFFLAGS, &network);
989
perror("ioctl SIOCGIFFLAGS");
990
} else if(network.ifr_flags & IFF_RUNNING){
993
struct timespec sleeptime = { .tv_nsec = 250000000 };
994
nanosleep(&sleeptime, NULL);
996
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1000
// Restores kernel loglevel to default
1001
ret = klogctl(7, NULL, 0);
1020
ret = init_gnutls_global(&mc, pubkey, seckey);
1022
fprintf(stderr, "init_gnutls_global failed\n");
1023
exitcode = EXIT_FAILURE;
1026
gnutls_initalized = true;
1029
if(mkdtemp(tempdir) == NULL){
1035
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1036
fprintf(stderr, "gpgme_initalized failed\n");
1037
exitcode = EXIT_FAILURE;
1040
gpgme_initalized = true;
1043
if_index = (AvahiIfIndex) if_nametoindex(interface);
1045
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1049
if(connect_to != NULL){
1050
/* Connect directly, do not use Zeroconf */
1051
/* (Mainly meant for debugging) */
1052
char *address = strrchr(connect_to, ':');
1053
if(address == NULL){
1054
fprintf(stderr, "No colon in address\n");
1055
exitcode = EXIT_FAILURE;
1059
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1060
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1061
or address[numchars+1] != '\0'){
1062
fprintf(stderr, "Bad port number\n");
1063
exitcode = EXIT_FAILURE;
1066
port = (uint16_t)tmpmax;
1068
address = connect_to;
1069
ret = start_mandos_communication(address, port, if_index, &mc);
1539
perror_plus("asprintf");
1543
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1546
pid_t hook_pid = fork();
1549
/* Raise privileges */
1550
if(raise_privileges_permanently() != 0){
1551
perror_plus("Failed to raise privileges");
1558
perror_plus("setgid");
1561
/* Reset supplementary groups */
1563
ret = setgroups(0, NULL);
1565
perror_plus("setgroups");
1568
ret = dup2(devnull, STDIN_FILENO);
1570
perror_plus("dup2(devnull, STDIN_FILENO)");
1573
ret = close(devnull);
1575
perror_plus("close");
1578
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1580
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1583
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1585
perror_plus("setenv");
1588
ret = setenv("DEVICE", interface, 1);
1590
perror_plus("setenv");
1593
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1595
perror_plus("setenv");
1598
ret = setenv("MODE", mode, 1);
1600
perror_plus("setenv");
1604
ret = asprintf(&delaystring, "%f", (double)delay);
1606
perror_plus("asprintf");
1609
ret = setenv("DELAY", delaystring, 1);
1612
perror_plus("setenv");
1616
if(connect_to != NULL){
1617
ret = setenv("CONNECT", connect_to, 1);
1619
perror_plus("setenv");
1071
exitcode = EXIT_FAILURE;
1073
exitcode = EXIT_SUCCESS;
1079
avahi_set_log_function(empty_log);
1082
/* Initialize the pseudo-RNG for Avahi */
1083
srand((unsigned int) time(NULL));
1085
/* Allocate main Avahi loop object */
1086
mc.simple_poll = avahi_simple_poll_new();
1087
if(mc.simple_poll == NULL) {
1088
fprintf(stderr, "Avahi: Failed to create simple poll"
1090
exitcode = EXIT_FAILURE;
1095
AvahiServerConfig config;
1096
/* Do not publish any local Zeroconf records */
1097
avahi_server_config_init(&config);
1098
config.publish_hinfo = 0;
1099
config.publish_addresses = 0;
1100
config.publish_workstation = 0;
1101
config.publish_domain = 0;
1103
/* Allocate a new server */
1104
mc.server = avahi_server_new(avahi_simple_poll_get
1105
(mc.simple_poll), &config, NULL,
1108
/* Free the Avahi configuration data */
1109
avahi_server_config_free(&config);
1112
/* Check if creating the Avahi server object succeeded */
1113
if(mc.server == NULL) {
1114
fprintf(stderr, "Failed to create Avahi server: %s\n",
1115
avahi_strerror(error));
1116
exitcode = EXIT_FAILURE;
1120
/* Create the Avahi service browser */
1121
sb = avahi_s_service_browser_new(mc.server, if_index,
1123
"_mandos._tcp", NULL, 0,
1124
browse_callback, &mc);
1126
fprintf(stderr, "Failed to create service browser: %s\n",
1127
avahi_strerror(avahi_server_errno(mc.server)));
1128
exitcode = EXIT_FAILURE;
1132
/* Run the main loop */
1135
fprintf(stderr, "Starting Avahi loop search\n");
1138
avahi_simple_poll_loop(mc.simple_poll);
1143
fprintf(stderr, "%s exiting\n", argv[0]);
1146
/* Cleanup things */
1148
avahi_s_service_browser_free(sb);
1150
if(mc.server != NULL)
1151
avahi_server_free(mc.server);
1153
if(mc.simple_poll != NULL)
1154
avahi_simple_poll_free(mc.simple_poll);
1156
if(gnutls_initalized){
1157
gnutls_certificate_free_credentials(mc.cred);
1158
gnutls_global_deinit();
1159
gnutls_dh_params_deinit(mc.dh_params);
1162
if(gpgme_initalized){
1163
gpgme_release(mc.ctx);
1166
/* Removes the temp directory used by GPGME */
1167
if(tempdir[0] != '\0'){
1169
struct dirent *direntry;
1170
d = opendir(tempdir);
1172
if(errno != ENOENT){
1177
direntry = readdir(d);
1178
if(direntry == NULL){
1623
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1624
perror_plus("execl");
1625
_exit(EXIT_FAILURE);
1629
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1630
perror_plus("waitpid");
1634
if(WIFEXITED(status)){
1635
if(WEXITSTATUS(status) != 0){
1636
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1637
" with status %d\n", direntry->d_name,
1638
WEXITSTATUS(status));
1181
if(direntry->d_type == DT_REG){
1182
char *fullname = NULL;
1183
ret = asprintf(&fullname, "%s/%s", tempdir,
1189
ret = unlink(fullname);
1191
fprintf(stderr, "unlink(\"%s\"): %s",
1192
fullname, strerror(errno));
1639
1194
free(fullname);
1642
} else if(WIFSIGNALED(status)){
1643
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1644
" signal %d\n", direntry->d_name,
1649
fprintf_plus(stderr, "Warning: network hook \"%s\""
1650
" crashed\n", direntry->d_name);
1657
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1665
__attribute__((nonnull, warn_unused_result))
1666
error_t bring_up_interface(const char *const interface,
1668
error_t old_errno = errno;
1670
struct ifreq network;
1671
unsigned int if_index = if_nametoindex(interface);
1673
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1683
if(not interface_is_up(interface)){
1684
error_t ret_errno = 0, ioctl_errno = 0;
1685
if(not get_flags(interface, &network)){
1687
fprintf_plus(stderr, "Failed to get flags for interface "
1688
"\"%s\"\n", interface);
1692
network.ifr_flags |= IFF_UP; /* set flag */
1694
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1697
perror_plus("socket");
1703
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1705
perror_plus("close");
1712
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1716
/* Raise privileges */
1717
ret_errno = raise_privileges();
1718
bool restore_loglevel = false;
1720
perror_plus("Failed to raise privileges");
1725
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1726
messages about the network interface to mess up the prompt */
1727
ret_linux = klogctl(8, NULL, 5);
1728
if(ret_linux == -1){
1729
perror_plus("klogctl");
1731
restore_loglevel = true;
1734
#endif /* __linux__ */
1735
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1736
ioctl_errno = errno;
1738
if(restore_loglevel){
1739
ret_linux = klogctl(7, NULL, 0);
1740
if(ret_linux == -1){
1741
perror_plus("klogctl");
1744
#endif /* __linux__ */
1746
/* If raise_privileges() succeeded above */
1748
/* Lower privileges */
1749
ret_errno = lower_privileges();
1752
perror_plus("Failed to lower privileges");
1756
/* Close the socket */
1757
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1759
perror_plus("close");
1762
if(ret_setflags == -1){
1763
errno = ioctl_errno;
1764
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1769
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1773
/* Sleep checking until interface is running.
1774
Check every 0.25s, up to total time of delay */
1775
for(int i=0; i < delay * 4; i++){
1776
if(interface_is_running(interface)){
1779
struct timespec sleeptime = { .tv_nsec = 250000000 };
1780
ret = nanosleep(&sleeptime, NULL);
1781
if(ret == -1 and errno != EINTR){
1782
perror_plus("nanosleep");
1790
__attribute__((nonnull, warn_unused_result))
1791
error_t take_down_interface(const char *const interface){
1792
error_t old_errno = errno;
1793
struct ifreq network;
1794
unsigned int if_index = if_nametoindex(interface);
1796
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1800
if(interface_is_up(interface)){
1801
error_t ret_errno = 0, ioctl_errno = 0;
1802
if(not get_flags(interface, &network) and debug){
1804
fprintf_plus(stderr, "Failed to get flags for interface "
1805
"\"%s\"\n", interface);
1809
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1811
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1814
perror_plus("socket");
1820
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1824
/* Raise privileges */
1825
ret_errno = raise_privileges();
1827
perror_plus("Failed to raise privileges");
1829
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1830
ioctl_errno = errno;
1832
/* If raise_privileges() succeeded above */
1834
/* Lower privileges */
1835
ret_errno = lower_privileges();
1838
perror_plus("Failed to lower privileges");
1842
/* Close the socket */
1843
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1845
perror_plus("close");
1848
if(ret_setflags == -1){
1849
errno = ioctl_errno;
1850
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1855
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1863
int main(int argc, char *argv[]){
1864
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1865
.priority = "SECURE256:!CTYPE-X.509:"
1866
"+CTYPE-OPENPGP", .current_server = NULL,
1867
.interfaces = NULL, .interfaces_size = 0 };
1868
AvahiSServiceBrowser *sb = NULL;
1873
int exitcode = EXIT_SUCCESS;
1874
char *interfaces_to_take_down = NULL;
1875
size_t interfaces_to_take_down_size = 0;
1876
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1877
char old_tempdir[] = "/tmp/mandosXXXXXX";
1878
char *tempdir = NULL;
1879
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1880
const char *seckey = PATHDIR "/" SECKEY;
1881
const char *pubkey = PATHDIR "/" PUBKEY;
1882
char *interfaces_hooks = NULL;
1884
bool gnutls_initialized = false;
1885
bool gpgme_initialized = false;
1887
double retry_interval = 10; /* 10s between trying a server and
1888
retrying the same server again */
1890
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1891
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1896
/* Lower any group privileges we might have, just to be safe */
1900
perror_plus("setgid");
1903
/* Lower user privileges (temporarily) */
1907
perror_plus("seteuid");
1915
struct argp_option options[] = {
1916
{ .name = "debug", .key = 128,
1917
.doc = "Debug mode", .group = 3 },
1918
{ .name = "connect", .key = 'c',
1919
.arg = "ADDRESS:PORT",
1920
.doc = "Connect directly to a specific Mandos server",
1922
{ .name = "interface", .key = 'i',
1924
.doc = "Network interface that will be used to search for"
1927
{ .name = "seckey", .key = 's',
1929
.doc = "OpenPGP secret key file base name",
1931
{ .name = "pubkey", .key = 'p',
1933
.doc = "OpenPGP public key file base name",
1935
{ .name = "dh-bits", .key = 129,
1937
.doc = "Bit length of the prime number used in the"
1938
" Diffie-Hellman key exchange",
1940
{ .name = "priority", .key = 130,
1942
.doc = "GnuTLS priority string for the TLS handshake",
1944
{ .name = "delay", .key = 131,
1946
.doc = "Maximum delay to wait for interface startup",
1948
{ .name = "retry", .key = 132,
1950
.doc = "Retry interval used when denied by the Mandos server",
1952
{ .name = "network-hook-dir", .key = 133,
1954
.doc = "Directory where network hooks are located",
1957
* These reproduce what we would get without ARGP_NO_HELP
1959
{ .name = "help", .key = '?',
1960
.doc = "Give this help list", .group = -1 },
1961
{ .name = "usage", .key = -3,
1962
.doc = "Give a short usage message", .group = -1 },
1963
{ .name = "version", .key = 'V',
1964
.doc = "Print program version", .group = -1 },
1968
error_t parse_opt(int key, char *arg,
1969
struct argp_state *state){
1972
case 128: /* --debug */
1975
case 'c': /* --connect */
1978
case 'i': /* --interface */
1979
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1982
argp_error(state, "%s", strerror(ret_errno));
1985
case 's': /* --seckey */
1988
case 'p': /* --pubkey */
1991
case 129: /* --dh-bits */
1993
tmpmax = strtoimax(arg, &tmp, 10);
1994
if(errno != 0 or tmp == arg or *tmp != '\0'
1995
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1996
argp_error(state, "Bad number of DH bits");
1998
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2000
case 130: /* --priority */
2003
case 131: /* --delay */
2005
delay = strtof(arg, &tmp);
2006
if(errno != 0 or tmp == arg or *tmp != '\0'){
2007
argp_error(state, "Bad delay");
2009
case 132: /* --retry */
2011
retry_interval = strtod(arg, &tmp);
2012
if(errno != 0 or tmp == arg or *tmp != '\0'
2013
or (retry_interval * 1000) > INT_MAX
2014
or retry_interval < 0){
2015
argp_error(state, "Bad retry interval");
2018
case 133: /* --network-hook-dir */
2022
* These reproduce what we would get without ARGP_NO_HELP
2024
case '?': /* --help */
2025
argp_state_help(state, state->out_stream,
2026
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2027
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2028
case -3: /* --usage */
2029
argp_state_help(state, state->out_stream,
2030
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2031
case 'V': /* --version */
2032
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2033
exit(argp_err_exit_status);
2036
return ARGP_ERR_UNKNOWN;
2041
struct argp argp = { .options = options, .parser = parse_opt,
2043
.doc = "Mandos client -- Get and decrypt"
2044
" passwords from a Mandos server" };
2045
ret = argp_parse(&argp, argc, argv,
2046
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2053
perror_plus("argp_parse");
2054
exitcode = EX_OSERR;
2057
exitcode = EX_USAGE;
2063
/* Work around Debian bug #633582:
2064
<http://bugs.debian.org/633582> */
2066
/* Re-raise privileges */
2067
ret_errno = raise_privileges();
2070
perror_plus("Failed to raise privileges");
2074
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2075
int seckey_fd = open(seckey, O_RDONLY);
2076
if(seckey_fd == -1){
2077
perror_plus("open");
2079
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2081
perror_plus("fstat");
2083
if(S_ISREG(st.st_mode)
2084
and st.st_uid == 0 and st.st_gid == 0){
2085
ret = fchown(seckey_fd, uid, gid);
2087
perror_plus("fchown");
2091
TEMP_FAILURE_RETRY(close(seckey_fd));
2095
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2096
int pubkey_fd = open(pubkey, O_RDONLY);
2097
if(pubkey_fd == -1){
2098
perror_plus("open");
2100
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2102
perror_plus("fstat");
2104
if(S_ISREG(st.st_mode)
2105
and st.st_uid == 0 and st.st_gid == 0){
2106
ret = fchown(pubkey_fd, uid, gid);
2108
perror_plus("fchown");
2112
TEMP_FAILURE_RETRY(close(pubkey_fd));
2116
/* Lower privileges */
2117
ret_errno = lower_privileges();
2120
perror_plus("Failed to lower privileges");
2125
/* Remove invalid interface names (except "none") */
2127
char *interface = NULL;
2128
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2130
if(strcmp(interface, "none") != 0
2131
and if_nametoindex(interface) == 0){
2132
if(interface[0] != '\0'){
2133
fprintf_plus(stderr, "Not using nonexisting interface"
2134
" \"%s\"\n", interface);
2136
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2142
/* Run network hooks */
2144
if(mc.interfaces != NULL){
2145
interfaces_hooks = malloc(mc.interfaces_size);
2146
if(interfaces_hooks == NULL){
2147
perror_plus("malloc");
2150
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2151
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2153
run_network_hooks("start", interfaces_hooks != NULL ?
2154
interfaces_hooks : "", delay);
2158
avahi_set_log_function(empty_log);
2161
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2162
from the signal handler */
2163
/* Initialize the pseudo-RNG for Avahi */
2164
srand((unsigned int) time(NULL));
2165
simple_poll = avahi_simple_poll_new();
2166
if(simple_poll == NULL){
2167
fprintf_plus(stderr,
2168
"Avahi: Failed to create simple poll object.\n");
2169
exitcode = EX_UNAVAILABLE;
2173
sigemptyset(&sigterm_action.sa_mask);
2174
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2176
perror_plus("sigaddset");
2177
exitcode = EX_OSERR;
2180
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2182
perror_plus("sigaddset");
2183
exitcode = EX_OSERR;
2186
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2188
perror_plus("sigaddset");
2189
exitcode = EX_OSERR;
2192
/* Need to check if the handler is SIG_IGN before handling:
2193
| [[info:libc:Initial Signal Actions]] |
2194
| [[info:libc:Basic Signal Handling]] |
2196
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2198
perror_plus("sigaction");
2201
if(old_sigterm_action.sa_handler != SIG_IGN){
2202
ret = sigaction(SIGINT, &sigterm_action, NULL);
2204
perror_plus("sigaction");
2205
exitcode = EX_OSERR;
2209
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2211
perror_plus("sigaction");
2214
if(old_sigterm_action.sa_handler != SIG_IGN){
2215
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2217
perror_plus("sigaction");
2218
exitcode = EX_OSERR;
2222
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2224
perror_plus("sigaction");
2227
if(old_sigterm_action.sa_handler != SIG_IGN){
2228
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2230
perror_plus("sigaction");
2231
exitcode = EX_OSERR;
2236
/* If no interfaces were specified, make a list */
2237
if(mc.interfaces == NULL){
2238
struct dirent **direntries;
2239
/* Look for any good interfaces */
2240
ret = scandir(sys_class_net, &direntries, good_interface,
2243
/* Add all found interfaces to interfaces list */
2244
for(int i = 0; i < ret; ++i){
2245
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2246
direntries[i]->d_name);
2249
perror_plus("argz_add");
2253
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2254
direntries[i]->d_name);
2260
fprintf_plus(stderr, "Could not find a network interface\n");
2261
exitcode = EXIT_FAILURE;
2266
/* Bring up interfaces which are down, and remove any "none"s */
2268
char *interface = NULL;
2269
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2271
/* If interface name is "none", stop bringing up interfaces.
2272
Also remove all instances of "none" from the list */
2273
if(strcmp(interface, "none") == 0){
2274
argz_delete(&mc.interfaces, &mc.interfaces_size,
2277
while((interface = argz_next(mc.interfaces,
2278
mc.interfaces_size, interface))){
2279
if(strcmp(interface, "none") == 0){
2280
argz_delete(&mc.interfaces, &mc.interfaces_size,
2287
bool interface_was_up = interface_is_up(interface);
2288
errno = bring_up_interface(interface, delay);
2289
if(not interface_was_up){
2291
perror_plus("Failed to bring up interface");
2293
errno = argz_add(&interfaces_to_take_down,
2294
&interfaces_to_take_down_size,
2297
perror_plus("argz_add");
2302
if(debug and (interfaces_to_take_down == NULL)){
2303
fprintf_plus(stderr, "No interfaces were brought up\n");
2307
/* If we only got one interface, explicitly use only that one */
2308
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2310
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2313
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2320
ret = init_gnutls_global(pubkey, seckey, &mc);
2322
fprintf_plus(stderr, "init_gnutls_global failed\n");
2323
exitcode = EX_UNAVAILABLE;
2326
gnutls_initialized = true;
2333
/* Try /run/tmp before /tmp */
2334
tempdir = mkdtemp(run_tempdir);
2335
if(tempdir == NULL and errno == ENOENT){
2337
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2338
run_tempdir, old_tempdir);
2340
tempdir = mkdtemp(old_tempdir);
2342
if(tempdir == NULL){
2343
perror_plus("mkdtemp");
2351
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2352
fprintf_plus(stderr, "init_gpgme failed\n");
2353
exitcode = EX_UNAVAILABLE;
2356
gpgme_initialized = true;
2363
if(connect_to != NULL){
2364
/* Connect directly, do not use Zeroconf */
2365
/* (Mainly meant for debugging) */
2366
char *address = strrchr(connect_to, ':');
2368
if(address == NULL){
2369
fprintf_plus(stderr, "No colon in address\n");
2370
exitcode = EX_USAGE;
2380
tmpmax = strtoimax(address+1, &tmp, 10);
2381
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2382
or tmpmax != (in_port_t)tmpmax){
2383
fprintf_plus(stderr, "Bad port number\n");
2384
exitcode = EX_USAGE;
2392
port = (in_port_t)tmpmax;
2394
/* Colon in address indicates IPv6 */
2396
if(strchr(connect_to, ':') != NULL){
2398
/* Accept [] around IPv6 address - see RFC 5952 */
2399
if(connect_to[0] == '[' and address[-1] == ']')
2407
address = connect_to;
2413
while(not quit_now){
2414
ret = start_mandos_communication(address, port, if_index, af,
2416
if(quit_now or ret == 0){
2420
fprintf_plus(stderr, "Retrying in %d seconds\n",
2421
(int)retry_interval);
2423
sleep((unsigned int)retry_interval);
2427
exitcode = EXIT_SUCCESS;
2438
AvahiServerConfig config;
2439
/* Do not publish any local Zeroconf records */
2440
avahi_server_config_init(&config);
2441
config.publish_hinfo = 0;
2442
config.publish_addresses = 0;
2443
config.publish_workstation = 0;
2444
config.publish_domain = 0;
2446
/* Allocate a new server */
2447
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2448
&config, NULL, NULL, &ret_errno);
2450
/* Free the Avahi configuration data */
2451
avahi_server_config_free(&config);
2454
/* Check if creating the Avahi server object succeeded */
2455
if(mc.server == NULL){
2456
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2457
avahi_strerror(ret_errno));
2458
exitcode = EX_UNAVAILABLE;
2466
/* Create the Avahi service browser */
2467
sb = avahi_s_service_browser_new(mc.server, if_index,
2468
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2469
NULL, 0, browse_callback,
2472
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2473
avahi_strerror(avahi_server_errno(mc.server)));
2474
exitcode = EX_UNAVAILABLE;
2482
/* Run the main loop */
2485
fprintf_plus(stderr, "Starting Avahi loop search\n");
2488
ret = avahi_loop_with_timeout(simple_poll,
2489
(int)(retry_interval * 1000), &mc);
2491
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2492
(ret == 0) ? "successfully" : "with error");
2498
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2501
/* Cleanup things */
2502
free(mc.interfaces);
2505
avahi_s_service_browser_free(sb);
2507
if(mc.server != NULL)
2508
avahi_server_free(mc.server);
2510
if(simple_poll != NULL)
2511
avahi_simple_poll_free(simple_poll);
2513
if(gnutls_initialized){
2514
gnutls_certificate_free_credentials(mc.cred);
2515
gnutls_global_deinit();
2516
gnutls_dh_params_deinit(mc.dh_params);
2519
if(gpgme_initialized){
2520
gpgme_release(mc.ctx);
2523
/* Cleans up the circular linked list of Mandos servers the client
2525
if(mc.current_server != NULL){
2526
mc.current_server->prev->next = NULL;
2527
while(mc.current_server != NULL){
2528
server *next = mc.current_server->next;
2529
free(mc.current_server);
2530
mc.current_server = next;
2534
/* Re-raise privileges */
2536
ret_errno = raise_privileges();
2538
perror_plus("Failed to raise privileges");
2541
/* Run network hooks */
2542
run_network_hooks("stop", interfaces_hooks != NULL ?
2543
interfaces_hooks : "", delay);
2545
/* Take down the network interfaces which were brought up */
2547
char *interface = NULL;
2548
while((interface=argz_next(interfaces_to_take_down,
2549
interfaces_to_take_down_size,
2551
ret_errno = take_down_interface(interface);
2554
perror_plus("Failed to take down interface");
2557
if(debug and (interfaces_to_take_down == NULL)){
2558
fprintf_plus(stderr, "No interfaces needed to be taken"
2563
ret_errno = lower_privileges_permanently();
2565
perror_plus("Failed to lower privileges permanently");
2569
free(interfaces_to_take_down);
2570
free(interfaces_hooks);
2572
/* Removes the GPGME temp directory and all files inside */
2573
if(tempdir != NULL){
2574
struct dirent **direntries = NULL;
2575
struct dirent *direntry = NULL;
2576
int numentries = scandir(tempdir, &direntries, notdotentries,
2579
for(int i = 0; i < numentries; i++){
2580
direntry = direntries[i];
2581
char *fullname = NULL;
2582
ret = asprintf(&fullname, "%s/%s", tempdir,
2585
perror_plus("asprintf");
2588
ret = remove(fullname);
2590
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2597
/* need to clean even if 0 because man page doesn't specify */
2599
if(numentries == -1){
2600
perror_plus("scandir");
2602
ret = rmdir(tempdir);
2603
if(ret == -1 and errno != ENOENT){
2604
perror_plus("rmdir");
2609
sigemptyset(&old_sigterm_action.sa_mask);
2610
old_sigterm_action.sa_handler = SIG_DFL;
2611
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2612
&old_sigterm_action,
2615
perror_plus("sigaction");
2618
ret = raise(signal_received);
2619
} while(ret != 0 and errno == EINTR);
2621
perror_plus("raise");
2624
TEMP_FAILURE_RETRY(pause());
1199
ret = rmdir(tempdir);
1200
if(ret == -1 and errno != ENOENT){