813
1278
case AVAHI_BROWSER_ALL_FOR_NOW:
814
1279
case AVAHI_BROWSER_CACHE_EXHAUSTED:
816
fprintf(stderr, "No Mandos server found, still searching...\n");
1281
fprintf_plus(stderr, "No Mandos server found, still"
1288
/* Signal handler that stops main loop after SIGTERM */
1289
static void handle_sigterm(int sig){
1294
signal_received = sig;
1295
int old_errno = errno;
1296
/* set main loop to exit */
1297
if(simple_poll != NULL){
1298
avahi_simple_poll_quit(simple_poll);
1303
__attribute__((nonnull, warn_unused_result))
1304
bool get_flags(const char *ifname, struct ifreq *ifr){
1308
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1311
perror_plus("socket");
1315
strcpy(ifr->ifr_name, ifname);
1316
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1320
perror_plus("ioctl SIOCGIFFLAGS");
1328
__attribute__((nonnull, warn_unused_result))
1329
bool good_flags(const char *ifname, const struct ifreq *ifr){
1331
/* Reject the loopback device */
1332
if(ifr->ifr_flags & IFF_LOOPBACK){
1334
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1339
/* Accept point-to-point devices only if connect_to is specified */
1340
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1342
fprintf_plus(stderr, "Accepting point-to-point interface"
1343
" \"%s\"\n", ifname);
1347
/* Otherwise, reject non-broadcast-capable devices */
1348
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1350
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1351
" \"%s\"\n", ifname);
1355
/* Reject non-ARP interfaces (including dummy interfaces) */
1356
if(ifr->ifr_flags & IFF_NOARP){
1358
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1364
/* Accept this device */
1366
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1372
* This function determines if a directory entry in /sys/class/net
1373
* corresponds to an acceptable network device.
1374
* (This function is passed to scandir(3) as a filter function.)
1376
__attribute__((nonnull, warn_unused_result))
1377
int good_interface(const struct dirent *if_entry){
1378
if(if_entry->d_name[0] == '.'){
1383
if(not get_flags(if_entry->d_name, &ifr)){
1385
fprintf_plus(stderr, "Failed to get flags for interface "
1386
"\"%s\"\n", if_entry->d_name);
1391
if(not good_flags(if_entry->d_name, &ifr)){
1398
* This function determines if a network interface is up.
1400
__attribute__((nonnull, warn_unused_result))
1401
bool interface_is_up(const char *interface){
1403
if(not get_flags(interface, &ifr)){
1405
fprintf_plus(stderr, "Failed to get flags for interface "
1406
"\"%s\"\n", interface);
1411
return (bool)(ifr.ifr_flags & IFF_UP);
1415
* This function determines if a network interface is running
1417
__attribute__((nonnull, warn_unused_result))
1418
bool interface_is_running(const char *interface){
1420
if(not get_flags(interface, &ifr)){
1422
fprintf_plus(stderr, "Failed to get flags for interface "
1423
"\"%s\"\n", interface);
1428
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1431
__attribute__((nonnull, pure, warn_unused_result))
1432
int notdotentries(const struct dirent *direntry){
1433
/* Skip "." and ".." */
1434
if(direntry->d_name[0] == '.'
1435
and (direntry->d_name[1] == '\0'
1436
or (direntry->d_name[1] == '.'
1437
and direntry->d_name[2] == '\0'))){
1443
/* Is this directory entry a runnable program? */
1444
__attribute__((nonnull, warn_unused_result))
1445
int runnable_hook(const struct dirent *direntry){
1450
if((direntry->d_name)[0] == '\0'){
1455
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1456
"abcdefghijklmnopqrstuvwxyz"
1459
if((direntry->d_name)[sret] != '\0'){
1460
/* Contains non-allowed characters */
1462
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1468
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1471
perror_plus("Could not stat hook");
1475
if(not (S_ISREG(st.st_mode))){
1476
/* Not a regular file */
1478
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1483
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1484
/* Not executable */
1486
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1492
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1498
__attribute__((nonnull, warn_unused_result))
1499
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1500
mandos_context *mc){
1502
struct timespec now;
1503
struct timespec waited_time;
1504
intmax_t block_time;
1507
if(mc->current_server == NULL){
1509
fprintf_plus(stderr, "Wait until first server is found."
1512
ret = avahi_simple_poll_iterate(s, -1);
1515
fprintf_plus(stderr, "Check current_server if we should run"
1518
/* the current time */
1519
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1521
perror_plus("clock_gettime");
1524
/* Calculating in ms how long time between now and server
1525
who we visted longest time ago. Now - last seen. */
1526
waited_time.tv_sec = (now.tv_sec
1527
- mc->current_server->last_seen.tv_sec);
1528
waited_time.tv_nsec = (now.tv_nsec
1529
- mc->current_server->last_seen.tv_nsec);
1530
/* total time is 10s/10,000ms.
1531
Converting to s from ms by dividing by 1,000,
1532
and ns to ms by dividing by 1,000,000. */
1533
block_time = ((retry_interval
1534
- ((intmax_t)waited_time.tv_sec * 1000))
1535
- ((intmax_t)waited_time.tv_nsec / 1000000));
1538
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1542
if(block_time <= 0){
1543
ret = start_mandos_communication(mc->current_server->ip,
1544
mc->current_server->port,
1545
mc->current_server->if_index,
1546
mc->current_server->af, mc);
1548
avahi_simple_poll_quit(s);
1551
ret = clock_gettime(CLOCK_MONOTONIC,
1552
&mc->current_server->last_seen);
1554
perror_plus("clock_gettime");
1557
mc->current_server = mc->current_server->next;
1558
block_time = 0; /* Call avahi to find new Mandos
1559
servers, but don't block */
1562
ret = avahi_simple_poll_iterate(s, (int)block_time);
1565
if(ret > 0 or errno != EINTR){
1566
return (ret != 1) ? ret : 0;
1572
/* Set effective uid to 0, return errno */
1573
__attribute__((warn_unused_result))
1574
error_t raise_privileges(void){
1575
error_t old_errno = errno;
1576
error_t ret_errno = 0;
1577
if(seteuid(0) == -1){
1584
/* Set effective and real user ID to 0. Return errno. */
1585
__attribute__((warn_unused_result))
1586
error_t raise_privileges_permanently(void){
1587
error_t old_errno = errno;
1588
error_t ret_errno = raise_privileges();
1593
if(setuid(0) == -1){
1600
/* Set effective user ID to unprivileged saved user ID */
1601
__attribute__((warn_unused_result))
1602
error_t lower_privileges(void){
1603
error_t old_errno = errno;
1604
error_t ret_errno = 0;
1605
if(seteuid(uid) == -1){
1612
/* Lower privileges permanently */
1613
__attribute__((warn_unused_result))
1614
error_t lower_privileges_permanently(void){
1615
error_t old_errno = errno;
1616
error_t ret_errno = 0;
1617
if(setuid(uid) == -1){
1624
__attribute__((nonnull))
1625
void run_network_hooks(const char *mode, const char *interface,
1627
struct dirent **direntries = NULL;
1628
if(hookdir_fd == -1){
1629
hookdir_fd = open(hookdir, O_RDONLY);
1630
if(hookdir_fd == -1){
1631
if(errno == ENOENT){
1633
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1634
" found\n", hookdir);
1637
perror_plus("open");
1643
#if __GLIBC_PREREQ(2, 15)
1644
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1645
runnable_hook, alphasort);
1646
#else /* not __GLIBC_PREREQ(2, 15) */
1647
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1649
#endif /* not __GLIBC_PREREQ(2, 15) */
1650
#else /* not __GLIBC__ */
1651
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1653
#endif /* not __GLIBC__ */
1655
perror_plus("scandir");
1658
struct dirent *direntry;
1660
int devnull = open("/dev/null", O_RDONLY);
1661
for(int i = 0; i < numhooks; i++){
1662
direntry = direntries[i];
1664
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1667
pid_t hook_pid = fork();
1670
/* Raise privileges */
1671
errno = raise_privileges_permanently();
1673
perror_plus("Failed to raise privileges");
1680
perror_plus("setgid");
1683
/* Reset supplementary groups */
1685
ret = setgroups(0, NULL);
1687
perror_plus("setgroups");
1690
ret = dup2(devnull, STDIN_FILENO);
1692
perror_plus("dup2(devnull, STDIN_FILENO)");
1695
ret = close(devnull);
1697
perror_plus("close");
1700
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1702
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1705
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1707
perror_plus("setenv");
1710
ret = setenv("DEVICE", interface, 1);
1712
perror_plus("setenv");
1715
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1717
perror_plus("setenv");
1720
ret = setenv("MODE", mode, 1);
1722
perror_plus("setenv");
1726
ret = asprintf(&delaystring, "%f", (double)delay);
1728
perror_plus("asprintf");
1731
ret = setenv("DELAY", delaystring, 1);
1734
perror_plus("setenv");
1738
if(connect_to != NULL){
1739
ret = setenv("CONNECT", connect_to, 1);
1741
perror_plus("setenv");
1745
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1747
perror_plus("openat");
1748
_exit(EXIT_FAILURE);
1750
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1751
perror_plus("close");
1752
_exit(EXIT_FAILURE);
1754
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1756
perror_plus("fexecve");
1757
_exit(EXIT_FAILURE);
1761
perror_plus("fork");
1766
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1767
perror_plus("waitpid");
1771
if(WIFEXITED(status)){
1772
if(WEXITSTATUS(status) != 0){
1773
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1774
" with status %d\n", direntry->d_name,
1775
WEXITSTATUS(status));
1779
} else if(WIFSIGNALED(status)){
1780
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1781
" signal %d\n", direntry->d_name,
1786
fprintf_plus(stderr, "Warning: network hook \"%s\""
1787
" crashed\n", direntry->d_name);
1793
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1799
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1800
perror_plus("close");
1807
__attribute__((nonnull, warn_unused_result))
1808
error_t bring_up_interface(const char *const interface,
1810
error_t old_errno = errno;
1812
struct ifreq network;
1813
unsigned int if_index = if_nametoindex(interface);
1815
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1825
if(not interface_is_up(interface)){
1826
error_t ret_errno = 0, ioctl_errno = 0;
1827
if(not get_flags(interface, &network)){
1829
fprintf_plus(stderr, "Failed to get flags for interface "
1830
"\"%s\"\n", interface);
1834
network.ifr_flags |= IFF_UP; /* set flag */
1836
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1839
perror_plus("socket");
1845
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1847
perror_plus("close");
1854
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1858
/* Raise privileges */
1859
ret_errno = raise_privileges();
1862
perror_plus("Failed to raise privileges");
1867
bool restore_loglevel = false;
1869
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1870
messages about the network interface to mess up the prompt */
1871
ret_linux = klogctl(8, NULL, 5);
1872
if(ret_linux == -1){
1873
perror_plus("klogctl");
1875
restore_loglevel = true;
1878
#endif /* __linux__ */
1879
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1880
ioctl_errno = errno;
1882
if(restore_loglevel){
1883
ret_linux = klogctl(7, NULL, 0);
1884
if(ret_linux == -1){
1885
perror_plus("klogctl");
1888
#endif /* __linux__ */
1890
/* If raise_privileges() succeeded above */
1892
/* Lower privileges */
1893
ret_errno = lower_privileges();
1896
perror_plus("Failed to lower privileges");
1900
/* Close the socket */
1901
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1903
perror_plus("close");
1906
if(ret_setflags == -1){
1907
errno = ioctl_errno;
1908
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1913
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1917
/* Sleep checking until interface is running.
1918
Check every 0.25s, up to total time of delay */
1919
for(int i=0; i < delay * 4; i++){
1920
if(interface_is_running(interface)){
1923
struct timespec sleeptime = { .tv_nsec = 250000000 };
1924
ret = nanosleep(&sleeptime, NULL);
1925
if(ret == -1 and errno != EINTR){
1926
perror_plus("nanosleep");
1934
__attribute__((nonnull, warn_unused_result))
1935
error_t take_down_interface(const char *const interface){
1936
error_t old_errno = errno;
1937
struct ifreq network;
1938
unsigned int if_index = if_nametoindex(interface);
1940
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1944
if(interface_is_up(interface)){
1945
error_t ret_errno = 0, ioctl_errno = 0;
1946
if(not get_flags(interface, &network) and debug){
1948
fprintf_plus(stderr, "Failed to get flags for interface "
1949
"\"%s\"\n", interface);
1953
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1955
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1958
perror_plus("socket");
1964
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1968
/* Raise privileges */
1969
ret_errno = raise_privileges();
1972
perror_plus("Failed to raise privileges");
1975
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1976
ioctl_errno = errno;
1978
/* If raise_privileges() succeeded above */
1980
/* Lower privileges */
1981
ret_errno = lower_privileges();
1984
perror_plus("Failed to lower privileges");
1988
/* Close the socket */
1989
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1991
perror_plus("close");
1994
if(ret_setflags == -1){
1995
errno = ioctl_errno;
1996
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2001
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
822
2009
int main(int argc, char *argv[]){
823
AvahiSServiceBrowser *sb = NULL;
828
int exitcode = EXIT_SUCCESS;
829
const char *interface = "eth0";
830
struct ifreq network;
834
char *connect_to = NULL;
835
char tempdir[] = "/tmp/mandosXXXXXX";
836
bool tempdir_created = false;
837
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
838
const char *seckey = PATHDIR "/" SECKEY;
839
const char *pubkey = PATHDIR "/" PUBKEY;
841
mandos_context mc = { .simple_poll = NULL, .server = NULL,
842
.dh_bits = 1024, .priority = "SECURE256"
843
":!CTYPE-X.509:+CTYPE-OPENPGP" };
844
bool gnutls_initialized = false;
845
bool gpgme_initialized = false;
849
struct argp_option options[] = {
850
{ .name = "debug", .key = 128,
851
.doc = "Debug mode", .group = 3 },
852
{ .name = "connect", .key = 'c',
853
.arg = "ADDRESS:PORT",
854
.doc = "Connect directly to a specific Mandos server",
856
{ .name = "interface", .key = 'i',
858
.doc = "Interface that will be used to search for Mandos"
861
{ .name = "seckey", .key = 's',
863
.doc = "OpenPGP secret key file base name",
865
{ .name = "pubkey", .key = 'p',
867
.doc = "OpenPGP public key file base name",
869
{ .name = "dh-bits", .key = 129,
871
.doc = "Bit length of the prime number used in the"
872
" Diffie-Hellman key exchange",
874
{ .name = "priority", .key = 130,
876
.doc = "GnuTLS priority string for the TLS handshake",
878
{ .name = "delay", .key = 131,
880
.doc = "Maximum delay to wait for interface startup",
885
error_t parse_opt(int key, char *arg,
886
struct argp_state *state) {
888
case 128: /* --debug */
891
case 'c': /* --connect */
894
case 'i': /* --interface */
897
case 's': /* --seckey */
900
case 'p': /* --pubkey */
903
case 129: /* --dh-bits */
904
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
905
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
906
or arg[numchars] != '\0'){
907
fprintf(stderr, "Bad number of DH bits\n");
910
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
912
case 130: /* --priority */
915
case 131: /* --delay */
916
ret = sscanf(arg, "%lf%n", &delay, &numchars);
917
if(ret < 1 or arg[numchars] != '\0'){
918
fprintf(stderr, "Bad delay\n");
927
return ARGP_ERR_UNKNOWN;
932
struct argp argp = { .options = options, .parser = parse_opt,
934
.doc = "Mandos client -- Get and decrypt"
935
" passwords from a Mandos server" };
936
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
937
if(ret == ARGP_ERR_UNKNOWN){
938
fprintf(stderr, "Unknown error while parsing arguments\n");
939
exitcode = EXIT_FAILURE;
944
/* If the interface is down, bring it up */
946
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
947
messages to mess up the prompt */
948
ret = klogctl(8, NULL, 5);
953
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
956
exitcode = EXIT_FAILURE;
957
ret = klogctl(7, NULL, 0);
963
strcpy(network.ifr_name, interface);
964
ret = ioctl(sd, SIOCGIFFLAGS, &network);
966
perror("ioctl SIOCGIFFLAGS");
967
ret = klogctl(7, NULL, 0);
971
exitcode = EXIT_FAILURE;
974
if((network.ifr_flags & IFF_UP) == 0){
975
network.ifr_flags |= IFF_UP;
976
ret = ioctl(sd, SIOCSIFFLAGS, &network);
978
perror("ioctl SIOCSIFFLAGS");
979
exitcode = EXIT_FAILURE;
980
ret = klogctl(7, NULL, 0);
987
/* sleep checking until interface is running */
988
for(int i=0; i < delay * 4; i++){
989
ret = ioctl(sd, SIOCGIFFLAGS, &network);
991
perror("ioctl SIOCGIFFLAGS");
992
} else if(network.ifr_flags & IFF_RUNNING){
995
struct timespec sleeptime = { .tv_nsec = 250000000 };
996
nanosleep(&sleeptime, NULL);
998
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1002
/* Restores kernel loglevel to default */
1003
ret = klogctl(7, NULL, 0);
1022
ret = init_gnutls_global(&mc, pubkey, seckey);
1024
fprintf(stderr, "init_gnutls_global failed\n");
1025
exitcode = EXIT_FAILURE;
1028
gnutls_initialized = true;
1031
if(mkdtemp(tempdir) == NULL){
1035
tempdir_created = true;
1037
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1038
fprintf(stderr, "init_gpgme failed\n");
1039
exitcode = EXIT_FAILURE;
1042
gpgme_initialized = true;
1045
if_index = (AvahiIfIndex) if_nametoindex(interface);
1047
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1048
exitcode = EXIT_FAILURE;
1052
if(connect_to != NULL){
1053
/* Connect directly, do not use Zeroconf */
1054
/* (Mainly meant for debugging) */
1055
char *address = strrchr(connect_to, ':');
1056
if(address == NULL){
1057
fprintf(stderr, "No colon in address\n");
1058
exitcode = EXIT_FAILURE;
1062
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1063
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1064
or address[numchars+1] != '\0'){
1065
fprintf(stderr, "Bad port number\n");
1066
exitcode = EXIT_FAILURE;
1069
port = (uint16_t)tmpmax;
1071
address = connect_to;
1072
ret = start_mandos_communication(address, port, if_index, &mc);
1074
exitcode = EXIT_FAILURE;
1076
exitcode = EXIT_SUCCESS;
1082
avahi_set_log_function(empty_log);
1085
/* Initialize the pseudo-RNG for Avahi */
1086
srand((unsigned int) time(NULL));
1088
/* Allocate main Avahi loop object */
1089
mc.simple_poll = avahi_simple_poll_new();
1090
if(mc.simple_poll == NULL) {
1091
fprintf(stderr, "Avahi: Failed to create simple poll"
1093
exitcode = EXIT_FAILURE;
1098
AvahiServerConfig config;
1099
/* Do not publish any local Zeroconf records */
1100
avahi_server_config_init(&config);
1101
config.publish_hinfo = 0;
1102
config.publish_addresses = 0;
1103
config.publish_workstation = 0;
1104
config.publish_domain = 0;
1106
/* Allocate a new server */
1107
mc.server = avahi_server_new(avahi_simple_poll_get
1108
(mc.simple_poll), &config, NULL,
1111
/* Free the Avahi configuration data */
1112
avahi_server_config_free(&config);
1115
/* Check if creating the Avahi server object succeeded */
1116
if(mc.server == NULL) {
1117
fprintf(stderr, "Failed to create Avahi server: %s\n",
1118
avahi_strerror(error));
1119
exitcode = EXIT_FAILURE;
1123
/* Create the Avahi service browser */
1124
sb = avahi_s_service_browser_new(mc.server, if_index,
1126
"_mandos._tcp", NULL, 0,
1127
browse_callback, &mc);
1129
fprintf(stderr, "Failed to create service browser: %s\n",
1130
avahi_strerror(avahi_server_errno(mc.server)));
1131
exitcode = EXIT_FAILURE;
1135
/* Run the main loop */
2010
mandos_context mc = { .server = NULL, .dh_bits = 0,
2011
.priority = "SECURE256:!CTYPE-X.509:"
2012
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
2013
.interfaces = NULL, .interfaces_size = 0 };
2014
AvahiSServiceBrowser *sb = NULL;
2019
int exitcode = EXIT_SUCCESS;
2020
char *interfaces_to_take_down = NULL;
2021
size_t interfaces_to_take_down_size = 0;
2022
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2023
char old_tempdir[] = "/tmp/mandosXXXXXX";
2024
char *tempdir = NULL;
2025
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2026
const char *seckey = PATHDIR "/" SECKEY;
2027
const char *pubkey = PATHDIR "/" PUBKEY;
2028
char *interfaces_hooks = NULL;
2030
bool gnutls_initialized = false;
2031
bool gpgme_initialized = false;
2033
double retry_interval = 10; /* 10s between trying a server and
2034
retrying the same server again */
2036
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2037
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2042
/* Lower any group privileges we might have, just to be safe */
2046
perror_plus("setgid");
2049
/* Lower user privileges (temporarily) */
2053
perror_plus("seteuid");
2061
struct argp_option options[] = {
2062
{ .name = "debug", .key = 128,
2063
.doc = "Debug mode", .group = 3 },
2064
{ .name = "connect", .key = 'c',
2065
.arg = "ADDRESS:PORT",
2066
.doc = "Connect directly to a specific Mandos server",
2068
{ .name = "interface", .key = 'i',
2070
.doc = "Network interface that will be used to search for"
2073
{ .name = "seckey", .key = 's',
2075
.doc = "OpenPGP secret key file base name",
2077
{ .name = "pubkey", .key = 'p',
2079
.doc = "OpenPGP public key file base name",
2081
{ .name = "dh-bits", .key = 129,
2083
.doc = "Bit length of the prime number used in the"
2084
" Diffie-Hellman key exchange",
2086
{ .name = "priority", .key = 130,
2088
.doc = "GnuTLS priority string for the TLS handshake",
2090
{ .name = "delay", .key = 131,
2092
.doc = "Maximum delay to wait for interface startup",
2094
{ .name = "retry", .key = 132,
2096
.doc = "Retry interval used when denied by the Mandos server",
2098
{ .name = "network-hook-dir", .key = 133,
2100
.doc = "Directory where network hooks are located",
2103
* These reproduce what we would get without ARGP_NO_HELP
2105
{ .name = "help", .key = '?',
2106
.doc = "Give this help list", .group = -1 },
2107
{ .name = "usage", .key = -3,
2108
.doc = "Give a short usage message", .group = -1 },
2109
{ .name = "version", .key = 'V',
2110
.doc = "Print program version", .group = -1 },
2114
error_t parse_opt(int key, char *arg,
2115
struct argp_state *state){
2118
case 128: /* --debug */
2121
case 'c': /* --connect */
2124
case 'i': /* --interface */
2125
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2128
argp_error(state, "%s", strerror(ret_errno));
2131
case 's': /* --seckey */
2134
case 'p': /* --pubkey */
2137
case 129: /* --dh-bits */
2139
tmpmax = strtoimax(arg, &tmp, 10);
2140
if(errno != 0 or tmp == arg or *tmp != '\0'
2141
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2142
argp_error(state, "Bad number of DH bits");
2144
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2146
case 130: /* --priority */
2149
case 131: /* --delay */
2151
delay = strtof(arg, &tmp);
2152
if(errno != 0 or tmp == arg or *tmp != '\0'){
2153
argp_error(state, "Bad delay");
2155
case 132: /* --retry */
2157
retry_interval = strtod(arg, &tmp);
2158
if(errno != 0 or tmp == arg or *tmp != '\0'
2159
or (retry_interval * 1000) > INT_MAX
2160
or retry_interval < 0){
2161
argp_error(state, "Bad retry interval");
2164
case 133: /* --network-hook-dir */
2168
* These reproduce what we would get without ARGP_NO_HELP
2170
case '?': /* --help */
2171
argp_state_help(state, state->out_stream,
2172
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2173
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2174
case -3: /* --usage */
2175
argp_state_help(state, state->out_stream,
2176
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2177
case 'V': /* --version */
2178
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2179
exit(argp_err_exit_status);
2182
return ARGP_ERR_UNKNOWN;
2187
struct argp argp = { .options = options, .parser = parse_opt,
2189
.doc = "Mandos client -- Get and decrypt"
2190
" passwords from a Mandos server" };
2191
ret = argp_parse(&argp, argc, argv,
2192
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2199
perror_plus("argp_parse");
2200
exitcode = EX_OSERR;
2203
exitcode = EX_USAGE;
2209
/* Work around Debian bug #633582:
2210
<http://bugs.debian.org/633582> */
2212
/* Re-raise privileges */
2213
ret_errno = raise_privileges();
2216
perror_plus("Failed to raise privileges");
2220
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2221
int seckey_fd = open(seckey, O_RDONLY);
2222
if(seckey_fd == -1){
2223
perror_plus("open");
2225
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2227
perror_plus("fstat");
2229
if(S_ISREG(st.st_mode)
2230
and st.st_uid == 0 and st.st_gid == 0){
2231
ret = fchown(seckey_fd, uid, gid);
2233
perror_plus("fchown");
2237
TEMP_FAILURE_RETRY(close(seckey_fd));
2241
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2242
int pubkey_fd = open(pubkey, O_RDONLY);
2243
if(pubkey_fd == -1){
2244
perror_plus("open");
2246
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2248
perror_plus("fstat");
2250
if(S_ISREG(st.st_mode)
2251
and st.st_uid == 0 and st.st_gid == 0){
2252
ret = fchown(pubkey_fd, uid, gid);
2254
perror_plus("fchown");
2258
TEMP_FAILURE_RETRY(close(pubkey_fd));
2262
/* Lower privileges */
2263
ret_errno = lower_privileges();
2266
perror_plus("Failed to lower privileges");
2271
/* Remove invalid interface names (except "none") */
2273
char *interface = NULL;
2274
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2276
if(strcmp(interface, "none") != 0
2277
and if_nametoindex(interface) == 0){
2278
if(interface[0] != '\0'){
2279
fprintf_plus(stderr, "Not using nonexisting interface"
2280
" \"%s\"\n", interface);
2282
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2288
/* Run network hooks */
2290
if(mc.interfaces != NULL){
2291
interfaces_hooks = malloc(mc.interfaces_size);
2292
if(interfaces_hooks == NULL){
2293
perror_plus("malloc");
2296
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2297
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2299
run_network_hooks("start", interfaces_hooks != NULL ?
2300
interfaces_hooks : "", delay);
2304
avahi_set_log_function(empty_log);
2307
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2308
from the signal handler */
2309
/* Initialize the pseudo-RNG for Avahi */
2310
srand((unsigned int) time(NULL));
2311
simple_poll = avahi_simple_poll_new();
2312
if(simple_poll == NULL){
2313
fprintf_plus(stderr,
2314
"Avahi: Failed to create simple poll object.\n");
2315
exitcode = EX_UNAVAILABLE;
2319
sigemptyset(&sigterm_action.sa_mask);
2320
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2322
perror_plus("sigaddset");
2323
exitcode = EX_OSERR;
2326
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2328
perror_plus("sigaddset");
2329
exitcode = EX_OSERR;
2332
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2334
perror_plus("sigaddset");
2335
exitcode = EX_OSERR;
2338
/* Need to check if the handler is SIG_IGN before handling:
2339
| [[info:libc:Initial Signal Actions]] |
2340
| [[info:libc:Basic Signal Handling]] |
2342
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2344
perror_plus("sigaction");
2347
if(old_sigterm_action.sa_handler != SIG_IGN){
2348
ret = sigaction(SIGINT, &sigterm_action, NULL);
2350
perror_plus("sigaction");
2351
exitcode = EX_OSERR;
2355
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2357
perror_plus("sigaction");
2360
if(old_sigterm_action.sa_handler != SIG_IGN){
2361
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2363
perror_plus("sigaction");
2364
exitcode = EX_OSERR;
2368
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2370
perror_plus("sigaction");
2373
if(old_sigterm_action.sa_handler != SIG_IGN){
2374
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2376
perror_plus("sigaction");
2377
exitcode = EX_OSERR;
2382
/* If no interfaces were specified, make a list */
2383
if(mc.interfaces == NULL){
2384
struct dirent **direntries = NULL;
2385
/* Look for any good interfaces */
2386
ret = scandir(sys_class_net, &direntries, good_interface,
2389
/* Add all found interfaces to interfaces list */
2390
for(int i = 0; i < ret; ++i){
2391
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2392
direntries[i]->d_name);
2395
perror_plus("argz_add");
2396
free(direntries[i]);
2400
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2401
direntries[i]->d_name);
2403
free(direntries[i]);
2410
fprintf_plus(stderr, "Could not find a network interface\n");
2411
exitcode = EXIT_FAILURE;
2416
/* Bring up interfaces which are down, and remove any "none"s */
2418
char *interface = NULL;
2419
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2421
/* If interface name is "none", stop bringing up interfaces.
2422
Also remove all instances of "none" from the list */
2423
if(strcmp(interface, "none") == 0){
2424
argz_delete(&mc.interfaces, &mc.interfaces_size,
2427
while((interface = argz_next(mc.interfaces,
2428
mc.interfaces_size, interface))){
2429
if(strcmp(interface, "none") == 0){
2430
argz_delete(&mc.interfaces, &mc.interfaces_size,
2437
bool interface_was_up = interface_is_up(interface);
2438
errno = bring_up_interface(interface, delay);
2439
if(not interface_was_up){
2441
perror_plus("Failed to bring up interface");
2443
errno = argz_add(&interfaces_to_take_down,
2444
&interfaces_to_take_down_size,
2447
perror_plus("argz_add");
2452
if(debug and (interfaces_to_take_down == NULL)){
2453
fprintf_plus(stderr, "No interfaces were brought up\n");
2457
/* If we only got one interface, explicitly use only that one */
2458
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
1138
fprintf(stderr, "Starting Avahi loop search\n");
1141
avahi_simple_poll_loop(mc.simple_poll);
2460
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2463
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2470
ret = init_gnutls_global(pubkey, seckey, &mc);
2472
fprintf_plus(stderr, "init_gnutls_global failed\n");
2473
exitcode = EX_UNAVAILABLE;
2476
gnutls_initialized = true;
2483
/* Try /run/tmp before /tmp */
2484
tempdir = mkdtemp(run_tempdir);
2485
if(tempdir == NULL and errno == ENOENT){
2487
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2488
run_tempdir, old_tempdir);
2490
tempdir = mkdtemp(old_tempdir);
2492
if(tempdir == NULL){
2493
perror_plus("mkdtemp");
2501
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2502
fprintf_plus(stderr, "init_gpgme failed\n");
2503
exitcode = EX_UNAVAILABLE;
2506
gpgme_initialized = true;
2513
if(connect_to != NULL){
2514
/* Connect directly, do not use Zeroconf */
2515
/* (Mainly meant for debugging) */
2516
char *address = strrchr(connect_to, ':');
2518
if(address == NULL){
2519
fprintf_plus(stderr, "No colon in address\n");
2520
exitcode = EX_USAGE;
2530
tmpmax = strtoimax(address+1, &tmp, 10);
2531
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2532
or tmpmax != (in_port_t)tmpmax){
2533
fprintf_plus(stderr, "Bad port number\n");
2534
exitcode = EX_USAGE;
2542
port = (in_port_t)tmpmax;
2544
/* Colon in address indicates IPv6 */
2546
if(strchr(connect_to, ':') != NULL){
2548
/* Accept [] around IPv6 address - see RFC 5952 */
2549
if(connect_to[0] == '[' and address[-1] == ']')
2557
address = connect_to;
2563
while(not quit_now){
2564
ret = start_mandos_communication(address, port, if_index, af,
2566
if(quit_now or ret == 0){
2570
fprintf_plus(stderr, "Retrying in %d seconds\n",
2571
(int)retry_interval);
2573
sleep((unsigned int)retry_interval);
2577
exitcode = EXIT_SUCCESS;
2588
AvahiServerConfig config;
2589
/* Do not publish any local Zeroconf records */
2590
avahi_server_config_init(&config);
2591
config.publish_hinfo = 0;
2592
config.publish_addresses = 0;
2593
config.publish_workstation = 0;
2594
config.publish_domain = 0;
2596
/* Allocate a new server */
2597
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2598
&config, NULL, NULL, &ret_errno);
2600
/* Free the Avahi configuration data */
2601
avahi_server_config_free(&config);
2604
/* Check if creating the Avahi server object succeeded */
2605
if(mc.server == NULL){
2606
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2607
avahi_strerror(ret_errno));
2608
exitcode = EX_UNAVAILABLE;
2616
/* Create the Avahi service browser */
2617
sb = avahi_s_service_browser_new(mc.server, if_index,
2618
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2619
NULL, 0, browse_callback,
2622
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2623
avahi_strerror(avahi_server_errno(mc.server)));
2624
exitcode = EX_UNAVAILABLE;
2632
/* Run the main loop */
2635
fprintf_plus(stderr, "Starting Avahi loop search\n");
2638
ret = avahi_loop_with_timeout(simple_poll,
2639
(int)(retry_interval * 1000), &mc);
2641
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2642
(ret == 0) ? "successfully" : "with error");
1146
fprintf(stderr, "%s exiting\n", argv[0]);
1149
/* Cleanup things */
1151
avahi_s_service_browser_free(sb);
1153
if(mc.server != NULL)
1154
avahi_server_free(mc.server);
1156
if(mc.simple_poll != NULL)
1157
avahi_simple_poll_free(mc.simple_poll);
1159
if(gnutls_initialized){
1160
gnutls_certificate_free_credentials(mc.cred);
1161
gnutls_global_deinit();
1162
gnutls_dh_params_deinit(mc.dh_params);
1165
if(gpgme_initialized){
1166
gpgme_release(mc.ctx);
1169
/* Removes the temp directory used by GPGME */
1170
if(tempdir_created){
1172
struct dirent *direntry;
1173
d = opendir(tempdir);
1175
if(errno != ENOENT){
1180
direntry = readdir(d);
1181
if(direntry == NULL){
1184
/* Skip "." and ".." */
1185
if(direntry->d_name[0] == '.'
1186
and (direntry->d_name[1] == '\0'
1187
or (direntry->d_name[1] == '.'
1188
and direntry->d_name[2] == '\0'))){
1191
char *fullname = NULL;
1192
ret = asprintf(&fullname, "%s/%s", tempdir,
1198
ret = remove(fullname);
2648
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2651
/* Cleanup things */
2652
free(mc.interfaces);
2655
avahi_s_service_browser_free(sb);
2657
if(mc.server != NULL)
2658
avahi_server_free(mc.server);
2660
if(simple_poll != NULL)
2661
avahi_simple_poll_free(simple_poll);
2663
if(gnutls_initialized){
2664
gnutls_certificate_free_credentials(mc.cred);
2665
gnutls_global_deinit();
2666
gnutls_dh_params_deinit(mc.dh_params);
2669
if(gpgme_initialized){
2670
gpgme_release(mc.ctx);
2673
/* Cleans up the circular linked list of Mandos servers the client
2675
if(mc.current_server != NULL){
2676
mc.current_server->prev->next = NULL;
2677
while(mc.current_server != NULL){
2678
server *next = mc.current_server->next;
2680
#pragma GCC diagnostic push
2681
#pragma GCC diagnostic ignored "-Wcast-qual"
2683
free((char *)(mc.current_server->ip));
2685
#pragma GCC diagnostic pop
2687
free(mc.current_server);
2688
mc.current_server = next;
2692
/* Re-raise privileges */
2694
ret_errno = raise_privileges();
2697
perror_plus("Failed to raise privileges");
2700
/* Run network hooks */
2701
run_network_hooks("stop", interfaces_hooks != NULL ?
2702
interfaces_hooks : "", delay);
2704
/* Take down the network interfaces which were brought up */
2706
char *interface = NULL;
2707
while((interface=argz_next(interfaces_to_take_down,
2708
interfaces_to_take_down_size,
2710
ret_errno = take_down_interface(interface);
2713
perror_plus("Failed to take down interface");
2716
if(debug and (interfaces_to_take_down == NULL)){
2717
fprintf_plus(stderr, "No interfaces needed to be taken"
2723
ret_errno = lower_privileges_permanently();
2726
perror_plus("Failed to lower privileges permanently");
2730
free(interfaces_to_take_down);
2731
free(interfaces_hooks);
2733
/* Removes the GPGME temp directory and all files inside */
2734
if(tempdir != NULL){
2735
struct dirent **direntries = NULL;
2736
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2738
if(tempdir_fd == -1){
2739
perror_plus("open");
2742
#if __GLIBC_PREREQ(2, 15)
2743
int numentries = scandirat(tempdir_fd, ".", &direntries,
2744
notdotentries, alphasort);
2745
#else /* not __GLIBC_PREREQ(2, 15) */
2746
int numentries = scandir(tempdir, &direntries, notdotentries,
2748
#endif /* not __GLIBC_PREREQ(2, 15) */
2749
#else /* not __GLIBC__ */
2750
int numentries = scandir(tempdir, &direntries, notdotentries,
2752
#endif /* not __GLIBC__ */
2753
if(numentries >= 0){
2754
for(int i = 0; i < numentries; i++){
2755
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
1200
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2757
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2758
" \"%s\", 0): %s\n", tempdir,
2759
direntries[i]->d_name, strerror(errno));
1207
ret = rmdir(tempdir);
1208
if(ret == -1 and errno != ENOENT){
2761
free(direntries[i]);
2764
/* need to clean even if 0 because man page doesn't specify */
2766
if(numentries == -1){
2767
perror_plus("scandir");
2769
ret = rmdir(tempdir);
2770
if(ret == -1 and errno != ENOENT){
2771
perror_plus("rmdir");
2774
TEMP_FAILURE_RETRY(close(tempdir_fd));
2779
sigemptyset(&old_sigterm_action.sa_mask);
2780
old_sigterm_action.sa_handler = SIG_DFL;
2781
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2782
&old_sigterm_action,
2785
perror_plus("sigaction");
2788
ret = raise(signal_received);
2789
} while(ret != 0 and errno == EINTR);
2791
perror_plus("raise");
2794
TEMP_FAILURE_RETRY(pause());