619
499
/* Called when a Mandos server is found */
620
500
static int start_mandos_communication(const char *ip, uint16_t port,
621
501
AvahiIfIndex if_index,
623
int ret, tcp_sd = -1;
626
struct sockaddr_in in;
627
struct sockaddr_in6 in6;
505
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
629
506
char *buffer = NULL;
630
char *decrypted_buffer = NULL;
507
char *decrypted_buffer;
631
508
size_t buffer_length = 0;
632
509
size_t buffer_capacity = 0;
510
ssize_t decrypted_buffer_size;
513
char interface[IF_NAMESIZE];
635
514
gnutls_session_t session;
636
int pf; /* Protocol family */
653
fprintf_plus(stderr, "Bad address family: %d\n", af);
658
ret = init_gnutls_session(&session);
664
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
665
PRIu16 "\n", ip, port);
668
tcp_sd = socket(pf, SOCK_STREAM, 0);
671
perror_plus("socket");
516
ret = init_gnutls_session (mc, &session);
522
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
526
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
533
if(if_indextoname((unsigned int)if_index, interface) == NULL){
534
perror("if_indextoname");
537
fprintf(stderr, "Binding to interface %s\n", interface);
681
540
memset(&to, 0, sizeof(to));
683
to.in6.sin6_family = (sa_family_t)af;
684
ret = inet_pton(af, ip, &to.in6.sin6_addr);
686
to.in.sin_family = (sa_family_t)af;
687
ret = inet_pton(af, ip, &to.in.sin_addr);
691
perror_plus("inet_pton");
541
to.in6.sin6_family = AF_INET6;
542
/* It would be nice to have a way to detect if we were passed an
543
IPv4 address here. Now we assume an IPv6 address. */
544
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
697
fprintf_plus(stderr, "Bad address: %s\n", ip);
702
to.in6.sin6_port = htons(port); /* Spurious warnings from
704
-Wunreachable-code */
706
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
707
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
709
if(if_index == AVAHI_IF_UNSPEC){
710
fprintf_plus(stderr, "An IPv6 link-local address is"
711
" incomplete without a network interface\n");
715
/* Set the network interface number as scope */
716
to.in6.sin6_scope_id = (uint32_t)if_index;
719
to.in.sin_port = htons(port); /* Spurious warnings from
721
-Wunreachable-code */
550
fprintf(stderr, "Bad address: %s\n", ip);
553
to.in6.sin6_port = htons(port); /* Spurious warning */
555
to.in6.sin6_scope_id = (uint32_t)if_index;
730
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
731
char interface[IF_NAMESIZE];
732
if(if_indextoname((unsigned int)if_index, interface) == NULL){
733
perror_plus("if_indextoname");
735
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
736
"\n", ip, interface, port);
739
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
742
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
743
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
746
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
749
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
753
perror_plus("inet_ntop");
558
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
560
char addrstr[INET6_ADDRSTRLEN] = "";
561
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
562
sizeof(addrstr)) == NULL){
755
565
if(strcmp(addrstr, ip) != 0){
756
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
566
fprintf(stderr, "Canonical address form: %s\n", addrstr);
767
ret = connect(tcp_sd, &to.in6, sizeof(to));
769
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
772
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
774
perror_plus("connect");
571
ret = connect(tcp_sd, &to.in, sizeof(to));
785
577
const char *out = mandos_protocol_version;
788
580
size_t out_size = strlen(out);
789
581
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
790
out_size - written));
793
perror_plus("write");
582
out_size - written));
797
588
written += (size_t)ret;
798
589
if(written < out_size){
801
if(out == mandos_protocol_version){
592
if (out == mandos_protocol_version){
816
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
824
/* This casting via intptr_t is to eliminate warning about casting
825
an int to a pointer type. This is exactly how the GnuTLS Guile
826
function "set-session-transport-fd!" does it. */
827
gnutls_transport_set_ptr(session,
828
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
836
ret = gnutls_handshake(session);
602
fprintf(stderr, "Establishing TLS session with %s\n", ip);
605
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
608
ret = gnutls_handshake (session);
841
609
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
843
if(ret != GNUTLS_E_SUCCESS){
611
if (ret != GNUTLS_E_SUCCESS){
845
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
613
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
852
620
/* Read OpenPGP packet that contains the wanted password */
855
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
623
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
866
buffer_capacity = incbuffer(&buffer, buffer_length,
868
if(buffer_capacity == 0){
870
perror_plus("incbuffer");
628
buffer_capacity = adjustbuffer(&buffer, buffer_length,
630
if (buffer_capacity == 0){
631
perror("adjustbuffer");
880
636
sret = gnutls_record_recv(session, buffer+buffer_length,
887
643
case GNUTLS_E_INTERRUPTED:
888
644
case GNUTLS_E_AGAIN:
890
646
case GNUTLS_E_REHANDSHAKE:
892
ret = gnutls_handshake(session);
648
ret = gnutls_handshake (session);
898
649
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
900
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
651
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
908
fprintf_plus(stderr, "Unknown error while reading data from"
909
" encrypted session with Mandos server\n");
910
gnutls_bye(session, GNUTLS_SHUT_RDWR);
658
fprintf(stderr, "Unknown error while reading data from"
659
" encrypted session with Mandos server\n");
661
gnutls_bye (session, GNUTLS_SHUT_RDWR);
1095
803
case AVAHI_BROWSER_ALL_FOR_NOW:
1096
804
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1098
fprintf_plus(stderr, "No Mandos server found, still"
806
fprintf(stderr, "No Mandos server found, still searching...\n");
1105
/* Signal handler that stops main loop after SIGTERM */
1106
static void handle_sigterm(int sig){
1111
signal_received = sig;
1112
int old_errno = errno;
1113
/* set main loop to exit */
1114
if(mc.simple_poll != NULL){
1115
avahi_simple_poll_quit(mc.simple_poll);
1120
bool get_flags(const char *ifname, struct ifreq *ifr){
1123
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1125
perror_plus("socket");
1128
strcpy(ifr->ifr_name, ifname);
1129
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1132
perror_plus("ioctl SIOCGIFFLAGS");
1139
bool good_flags(const char *ifname, const struct ifreq *ifr){
1141
/* Reject the loopback device */
1142
if(ifr->ifr_flags & IFF_LOOPBACK){
1144
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1149
/* Accept point-to-point devices only if connect_to is specified */
1150
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1152
fprintf_plus(stderr, "Accepting point-to-point interface"
1153
" \"%s\"\n", ifname);
1157
/* Otherwise, reject non-broadcast-capable devices */
1158
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1160
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1161
" \"%s\"\n", ifname);
1165
/* Reject non-ARP interfaces (including dummy interfaces) */
1166
if(ifr->ifr_flags & IFF_NOARP){
1168
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1174
/* Accept this device */
1176
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1182
* This function determines if a directory entry in /sys/class/net
1183
* corresponds to an acceptable network device.
1184
* (This function is passed to scandir(3) as a filter function.)
1186
int good_interface(const struct dirent *if_entry){
1187
if(if_entry->d_name[0] == '.'){
1192
if(not get_flags(if_entry->d_name, &ifr)){
1194
fprintf_plus(stderr, "Failed to get flags for interface "
1195
"\"%s\"\n", if_entry->d_name);
1200
if(not good_flags(if_entry->d_name, &ifr)){
1207
* This function determines if a directory entry in /sys/class/net
1208
* corresponds to an acceptable network device which is up.
1209
* (This function is passed to scandir(3) as a filter function.)
1211
int up_interface(const struct dirent *if_entry){
1212
if(if_entry->d_name[0] == '.'){
1217
if(not get_flags(if_entry->d_name, &ifr)){
1219
fprintf_plus(stderr, "Failed to get flags for interface "
1220
"\"%s\"\n", if_entry->d_name);
1225
/* Reject down interfaces */
1226
if(not (ifr.ifr_flags & IFF_UP)){
1228
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1234
/* Reject non-running interfaces */
1235
if(not (ifr.ifr_flags & IFF_RUNNING)){
1237
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1243
if(not good_flags(if_entry->d_name, &ifr)){
1249
int notdotentries(const struct dirent *direntry){
1250
/* Skip "." and ".." */
1251
if(direntry->d_name[0] == '.'
1252
and (direntry->d_name[1] == '\0'
1253
or (direntry->d_name[1] == '.'
1254
and direntry->d_name[2] == '\0'))){
1260
/* Is this directory entry a runnable program? */
1261
int runnable_hook(const struct dirent *direntry){
1266
if((direntry->d_name)[0] == '\0'){
1271
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1272
"abcdefghijklmnopqrstuvwxyz"
1275
if((direntry->d_name)[sret] != '\0'){
1276
/* Contains non-allowed characters */
1278
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1284
char *fullname = NULL;
1285
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1287
perror_plus("asprintf");
1291
ret = stat(fullname, &st);
1294
perror_plus("Could not stat hook");
1298
if(not (S_ISREG(st.st_mode))){
1299
/* Not a regular file */
1301
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1306
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1307
/* Not executable */
1309
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1315
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1321
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1323
struct timespec now;
1324
struct timespec waited_time;
1325
intmax_t block_time;
1328
if(mc.current_server == NULL){
1330
fprintf_plus(stderr, "Wait until first server is found."
1333
ret = avahi_simple_poll_iterate(s, -1);
1336
fprintf_plus(stderr, "Check current_server if we should run"
1339
/* the current time */
1340
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1342
perror_plus("clock_gettime");
1345
/* Calculating in ms how long time between now and server
1346
who we visted longest time ago. Now - last seen. */
1347
waited_time.tv_sec = (now.tv_sec
1348
- mc.current_server->last_seen.tv_sec);
1349
waited_time.tv_nsec = (now.tv_nsec
1350
- mc.current_server->last_seen.tv_nsec);
1351
/* total time is 10s/10,000ms.
1352
Converting to s from ms by dividing by 1,000,
1353
and ns to ms by dividing by 1,000,000. */
1354
block_time = ((retry_interval
1355
- ((intmax_t)waited_time.tv_sec * 1000))
1356
- ((intmax_t)waited_time.tv_nsec / 1000000));
1359
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1363
if(block_time <= 0){
1364
ret = start_mandos_communication(mc.current_server->ip,
1365
mc.current_server->port,
1366
mc.current_server->if_index,
1367
mc.current_server->af);
1369
avahi_simple_poll_quit(mc.simple_poll);
1372
ret = clock_gettime(CLOCK_MONOTONIC,
1373
&mc.current_server->last_seen);
1375
perror_plus("clock_gettime");
1378
mc.current_server = mc.current_server->next;
1379
block_time = 0; /* Call avahi to find new Mandos
1380
servers, but don't block */
1383
ret = avahi_simple_poll_iterate(s, (int)block_time);
1386
if (ret > 0 or errno != EINTR){
1387
return (ret != 1) ? ret : 0;
1393
bool run_network_hooks(const char *mode, const char *interface,
1395
struct dirent **direntries;
1396
struct dirent *direntry;
1398
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1401
perror_plus("scandir");
1403
int devnull = open("/dev/null", O_RDONLY);
1404
for(int i = 0; i < numhooks; i++){
1405
direntry = direntries[i];
1406
char *fullname = NULL;
1407
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1409
perror_plus("asprintf");
1413
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1416
pid_t hook_pid = fork();
1419
/* Raise privileges */
1423
perror_plus("seteuid");
1425
/* Raise privileges even more */
1429
perror_plus("setuid");
1435
perror_plus("setgid");
1437
/* Reset supplementary groups */
1439
ret = setgroups(0, NULL);
1441
perror_plus("setgroups");
1443
dup2(devnull, STDIN_FILENO);
1445
dup2(STDERR_FILENO, STDOUT_FILENO);
1446
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1448
perror_plus("setenv");
1451
ret = setenv("DEVICE", interface, 1);
1453
perror_plus("setenv");
1456
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1458
perror_plus("setenv");
1461
ret = setenv("MODE", mode, 1);
1463
perror_plus("setenv");
1467
ret = asprintf(&delaystring, "%f", delay);
1469
perror_plus("asprintf");
1472
ret = setenv("DELAY", delaystring, 1);
1475
perror_plus("setenv");
1479
if(connect_to != NULL){
1480
ret = setenv("CONNECT", connect_to, 1);
1482
perror_plus("setenv");
1486
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1487
perror_plus("execl");
1488
_exit(EXIT_FAILURE);
1492
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1493
perror_plus("waitpid");
1497
if(WIFEXITED(status)){
1498
if(WEXITSTATUS(status) != 0){
1499
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1500
" with status %d\n", direntry->d_name,
1501
WEXITSTATUS(status));
1505
} else if(WIFSIGNALED(status)){
1506
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1507
" signal %d\n", direntry->d_name,
1512
fprintf_plus(stderr, "Warning: network hook \"%s\""
1513
" crashed\n", direntry->d_name);
1520
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1529
812
int main(int argc, char *argv[]){
1530
AvahiSServiceBrowser *sb = NULL;
1535
int exitcode = EXIT_SUCCESS;
1536
const char *interface = "";
1537
struct ifreq network;
1539
bool take_down_interface = false;
1542
char tempdir[] = "/tmp/mandosXXXXXX";
1543
bool tempdir_created = false;
1544
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1545
const char *seckey = PATHDIR "/" SECKEY;
1546
const char *pubkey = PATHDIR "/" PUBKEY;
1548
bool gnutls_initialized = false;
1549
bool gpgme_initialized = false;
1551
double retry_interval = 10; /* 10s between trying a server and
1552
retrying the same server again */
1554
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1555
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1560
/* Lower any group privileges we might have, just to be safe */
1564
perror_plus("setgid");
1567
/* Lower user privileges (temporarily) */
1571
perror_plus("seteuid");
1579
struct argp_option options[] = {
1580
{ .name = "debug", .key = 128,
1581
.doc = "Debug mode", .group = 3 },
1582
{ .name = "connect", .key = 'c',
1583
.arg = "ADDRESS:PORT",
1584
.doc = "Connect directly to a specific Mandos server",
1586
{ .name = "interface", .key = 'i',
1588
.doc = "Network interface that will be used to search for"
1591
{ .name = "seckey", .key = 's',
1593
.doc = "OpenPGP secret key file base name",
1595
{ .name = "pubkey", .key = 'p',
1597
.doc = "OpenPGP public key file base name",
1599
{ .name = "dh-bits", .key = 129,
1601
.doc = "Bit length of the prime number used in the"
1602
" Diffie-Hellman key exchange",
1604
{ .name = "priority", .key = 130,
1606
.doc = "GnuTLS priority string for the TLS handshake",
1608
{ .name = "delay", .key = 131,
1610
.doc = "Maximum delay to wait for interface startup",
1612
{ .name = "retry", .key = 132,
1614
.doc = "Retry interval used when denied by the Mandos server",
1616
{ .name = "network-hook-dir", .key = 133,
1618
.doc = "Directory where network hooks are located",
1621
* These reproduce what we would get without ARGP_NO_HELP
1623
{ .name = "help", .key = '?',
1624
.doc = "Give this help list", .group = -1 },
1625
{ .name = "usage", .key = -3,
1626
.doc = "Give a short usage message", .group = -1 },
1627
{ .name = "version", .key = 'V',
1628
.doc = "Print program version", .group = -1 },
1632
error_t parse_opt(int key, char *arg,
1633
struct argp_state *state){
1636
case 128: /* --debug */
1639
case 'c': /* --connect */
1642
case 'i': /* --interface */
1645
case 's': /* --seckey */
1648
case 'p': /* --pubkey */
1651
case 129: /* --dh-bits */
1653
tmpmax = strtoimax(arg, &tmp, 10);
1654
if(errno != 0 or tmp == arg or *tmp != '\0'
1655
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1656
argp_error(state, "Bad number of DH bits");
1658
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1660
case 130: /* --priority */
1663
case 131: /* --delay */
1665
delay = strtof(arg, &tmp);
1666
if(errno != 0 or tmp == arg or *tmp != '\0'){
1667
argp_error(state, "Bad delay");
1669
case 132: /* --retry */
1671
retry_interval = strtod(arg, &tmp);
1672
if(errno != 0 or tmp == arg or *tmp != '\0'
1673
or (retry_interval * 1000) > INT_MAX
1674
or retry_interval < 0){
1675
argp_error(state, "Bad retry interval");
1678
case 133: /* --network-hook-dir */
1682
* These reproduce what we would get without ARGP_NO_HELP
1684
case '?': /* --help */
1685
argp_state_help(state, state->out_stream,
1686
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1687
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1688
case -3: /* --usage */
1689
argp_state_help(state, state->out_stream,
1690
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1691
case 'V': /* --version */
1692
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1693
exit(argp_err_exit_status);
1696
return ARGP_ERR_UNKNOWN;
1701
struct argp argp = { .options = options, .parser = parse_opt,
1703
.doc = "Mandos client -- Get and decrypt"
1704
" passwords from a Mandos server" };
1705
ret = argp_parse(&argp, argc, argv,
1706
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1713
perror_plus("argp_parse");
1714
exitcode = EX_OSERR;
1717
exitcode = EX_USAGE;
1723
/* Work around Debian bug #633582:
1724
<http://bugs.debian.org/633582> */
1726
/* Re-raise priviliges */
1730
perror_plus("seteuid");
1734
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1735
int seckey_fd = open(seckey, O_RDONLY);
1736
if(seckey_fd == -1){
1737
perror_plus("open");
1739
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1741
perror_plus("fstat");
1743
if(S_ISREG(st.st_mode)
1744
and st.st_uid == 0 and st.st_gid == 0){
1745
ret = fchown(seckey_fd, uid, gid);
1747
perror_plus("fchown");
1751
TEMP_FAILURE_RETRY(close(seckey_fd));
1755
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1756
int pubkey_fd = open(pubkey, O_RDONLY);
1757
if(pubkey_fd == -1){
1758
perror_plus("open");
1760
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1762
perror_plus("fstat");
1764
if(S_ISREG(st.st_mode)
1765
and st.st_uid == 0 and st.st_gid == 0){
1766
ret = fchown(pubkey_fd, uid, gid);
1768
perror_plus("fchown");
1772
TEMP_FAILURE_RETRY(close(pubkey_fd));
1776
/* Lower privileges */
1780
perror_plus("seteuid");
1785
/* Run network hooks */
1786
if(not run_network_hooks("start", interface, delay)){
1791
avahi_set_log_function(empty_log);
1794
if(interface[0] == '\0'){
1795
struct dirent **direntries;
1796
/* First look for interfaces that are up */
1797
ret = scandir(sys_class_net, &direntries, up_interface,
1800
/* No up interfaces, look for any good interfaces */
1802
ret = scandir(sys_class_net, &direntries, good_interface,
1806
/* Pick the first interface returned */
1807
interface = strdup(direntries[0]->d_name);
1809
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1811
if(interface == NULL){
1812
perror_plus("malloc");
1814
exitcode = EXIT_FAILURE;
1820
fprintf_plus(stderr, "Could not find a network interface\n");
1821
exitcode = EXIT_FAILURE;
1826
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1827
from the signal handler */
1828
/* Initialize the pseudo-RNG for Avahi */
1829
srand((unsigned int) time(NULL));
1830
mc.simple_poll = avahi_simple_poll_new();
1831
if(mc.simple_poll == NULL){
1832
fprintf_plus(stderr,
1833
"Avahi: Failed to create simple poll object.\n");
1834
exitcode = EX_UNAVAILABLE;
1838
sigemptyset(&sigterm_action.sa_mask);
1839
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1841
perror_plus("sigaddset");
1842
exitcode = EX_OSERR;
1845
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1847
perror_plus("sigaddset");
1848
exitcode = EX_OSERR;
1851
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1853
perror_plus("sigaddset");
1854
exitcode = EX_OSERR;
1857
/* Need to check if the handler is SIG_IGN before handling:
1858
| [[info:libc:Initial Signal Actions]] |
1859
| [[info:libc:Basic Signal Handling]] |
1861
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1863
perror_plus("sigaction");
1866
if(old_sigterm_action.sa_handler != SIG_IGN){
1867
ret = sigaction(SIGINT, &sigterm_action, NULL);
1869
perror_plus("sigaction");
1870
exitcode = EX_OSERR;
1874
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1876
perror_plus("sigaction");
1879
if(old_sigterm_action.sa_handler != SIG_IGN){
1880
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1882
perror_plus("sigaction");
1883
exitcode = EX_OSERR;
1887
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1889
perror_plus("sigaction");
1892
if(old_sigterm_action.sa_handler != SIG_IGN){
1893
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1895
perror_plus("sigaction");
1896
exitcode = EX_OSERR;
1901
/* If the interface is down, bring it up */
1902
if(strcmp(interface, "none") != 0){
813
AvahiSServiceBrowser *sb = NULL;
816
int exitcode = EXIT_SUCCESS;
817
const char *interface = "eth0";
818
struct ifreq network;
822
char *connect_to = NULL;
823
char tempdir[] = "/tmp/mandosXXXXXX";
824
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
825
const char *seckey = PATHDIR "/" SECKEY;
826
const char *pubkey = PATHDIR "/" PUBKEY;
828
mandos_context mc = { .simple_poll = NULL, .server = NULL,
829
.dh_bits = 1024, .priority = "SECURE256"
830
":!CTYPE-X.509:+CTYPE-OPENPGP" };
831
bool gnutls_initalized = false;
832
bool gpgme_initalized = false;
835
struct argp_option options[] = {
836
{ .name = "debug", .key = 128,
837
.doc = "Debug mode", .group = 3 },
838
{ .name = "connect", .key = 'c',
839
.arg = "ADDRESS:PORT",
840
.doc = "Connect directly to a specific Mandos server",
842
{ .name = "interface", .key = 'i',
844
.doc = "Interface that will be used to search for Mandos"
847
{ .name = "seckey", .key = 's',
849
.doc = "OpenPGP secret key file base name",
851
{ .name = "pubkey", .key = 'p',
853
.doc = "OpenPGP public key file base name",
855
{ .name = "dh-bits", .key = 129,
857
.doc = "Bit length of the prime number used in the"
858
" Diffie-Hellman key exchange",
860
{ .name = "priority", .key = 130,
862
.doc = "GnuTLS priority string for the TLS handshake",
867
error_t parse_opt (int key, char *arg,
868
struct argp_state *state) {
869
/* Get the INPUT argument from `argp_parse', which we know is
870
a pointer to our plugin list pointer. */
872
case 128: /* --debug */
875
case 'c': /* --connect */
878
case 'i': /* --interface */
881
case 's': /* --seckey */
884
case 'p': /* --pubkey */
887
case 129: /* --dh-bits */
889
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
895
case 130: /* --priority */
903
return ARGP_ERR_UNKNOWN;
908
struct argp argp = { .options = options, .parser = parse_opt,
910
.doc = "Mandos client -- Get and decrypt"
911
" passwords from a Mandos server" };
912
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
913
if (ret == ARGP_ERR_UNKNOWN){
914
fprintf(stderr, "Unknown error while parsing arguments\n");
915
exitcode = EXIT_FAILURE;
920
/* If the interface is down, bring it up */
922
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
925
exitcode = EXIT_FAILURE;
928
strcpy(network.ifr_name, interface);
929
ret = ioctl(sd, SIOCGIFFLAGS, &network);
931
perror("ioctl SIOCGIFFLAGS");
932
exitcode = EXIT_FAILURE;
935
if((network.ifr_flags & IFF_UP) == 0){
936
network.ifr_flags |= IFF_UP;
937
ret = ioctl(sd, SIOCSIFFLAGS, &network);
939
perror("ioctl SIOCSIFFLAGS");
940
exitcode = EXIT_FAILURE;
944
ret = (int)TEMP_FAILURE_RETRY(close(sd));
963
ret = init_gnutls_global(&mc, pubkey, seckey);
965
fprintf(stderr, "init_gnutls_global failed\n");
966
exitcode = EXIT_FAILURE;
969
gnutls_initalized = true;
972
if(mkdtemp(tempdir) == NULL){
978
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
979
fprintf(stderr, "gpgme_initalized failed\n");
980
exitcode = EXIT_FAILURE;
983
gpgme_initalized = true;
1903
986
if_index = (AvahiIfIndex) if_nametoindex(interface);
1904
987
if(if_index == 0){
1905
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1906
exitcode = EX_UNAVAILABLE;
1914
/* Re-raise priviliges */
1918
perror_plus("seteuid");
1922
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1923
messages about the network interface to mess up the prompt */
1924
ret = klogctl(8, NULL, 5);
1925
bool restore_loglevel = true;
1927
restore_loglevel = false;
1928
perror_plus("klogctl");
1930
#endif /* __linux__ */
1932
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1934
perror_plus("socket");
1935
exitcode = EX_OSERR;
1937
if(restore_loglevel){
1938
ret = klogctl(7, NULL, 0);
1940
perror_plus("klogctl");
1943
#endif /* __linux__ */
1944
/* Lower privileges */
1948
perror_plus("seteuid");
1952
strcpy(network.ifr_name, interface);
1953
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1955
perror_plus("ioctl SIOCGIFFLAGS");
1957
if(restore_loglevel){
1958
ret = klogctl(7, NULL, 0);
1960
perror_plus("klogctl");
1963
#endif /* __linux__ */
1964
exitcode = EX_OSERR;
1965
/* Lower privileges */
1969
perror_plus("seteuid");
1973
if((network.ifr_flags & IFF_UP) == 0){
1974
network.ifr_flags |= IFF_UP;
1975
take_down_interface = true;
1976
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1978
take_down_interface = false;
1979
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1980
exitcode = EX_OSERR;
1982
if(restore_loglevel){
1983
ret = klogctl(7, NULL, 0);
1985
perror_plus("klogctl");
1988
#endif /* __linux__ */
1989
/* Lower privileges */
1993
perror_plus("seteuid");
1998
/* Sleep checking until interface is running.
1999
Check every 0.25s, up to total time of delay */
2000
for(int i=0; i < delay * 4; i++){
2001
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2003
perror_plus("ioctl SIOCGIFFLAGS");
2004
} else if(network.ifr_flags & IFF_RUNNING){
2007
struct timespec sleeptime = { .tv_nsec = 250000000 };
2008
ret = nanosleep(&sleeptime, NULL);
2009
if(ret == -1 and errno != EINTR){
2010
perror_plus("nanosleep");
2013
if(not take_down_interface){
2014
/* We won't need the socket anymore */
2015
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2017
perror_plus("close");
2021
if(restore_loglevel){
2022
/* Restores kernel loglevel to default */
2023
ret = klogctl(7, NULL, 0);
2025
perror_plus("klogctl");
2028
#endif /* __linux__ */
2029
/* Lower privileges */
2031
/* Lower privileges */
2034
perror_plus("seteuid");
2042
ret = init_gnutls_global(pubkey, seckey);
2044
fprintf_plus(stderr, "init_gnutls_global failed\n");
2045
exitcode = EX_UNAVAILABLE;
2048
gnutls_initialized = true;
2055
if(mkdtemp(tempdir) == NULL){
2056
perror_plus("mkdtemp");
2059
tempdir_created = true;
2065
if(not init_gpgme(pubkey, seckey, tempdir)){
2066
fprintf_plus(stderr, "init_gpgme failed\n");
2067
exitcode = EX_UNAVAILABLE;
2070
gpgme_initialized = true;
2077
if(connect_to != NULL){
2078
/* Connect directly, do not use Zeroconf */
2079
/* (Mainly meant for debugging) */
2080
char *address = strrchr(connect_to, ':');
2081
if(address == NULL){
2082
fprintf_plus(stderr, "No colon in address\n");
2083
exitcode = EX_USAGE;
2093
tmpmax = strtoimax(address+1, &tmp, 10);
2094
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2095
or tmpmax != (uint16_t)tmpmax){
2096
fprintf_plus(stderr, "Bad port number\n");
2097
exitcode = EX_USAGE;
2105
port = (uint16_t)tmpmax;
2107
/* Colon in address indicates IPv6 */
2109
if(strchr(connect_to, ':') != NULL){
2111
/* Accept [] around IPv6 address - see RFC 5952 */
2112
if(connect_to[0] == '[' and address[-1] == ']')
2120
address = connect_to;
2126
while(not quit_now){
2127
ret = start_mandos_communication(address, port, if_index, af);
2128
if(quit_now or ret == 0){
2132
fprintf_plus(stderr, "Retrying in %d seconds\n",
2133
(int)retry_interval);
2135
sleep((int)retry_interval);
2139
exitcode = EXIT_SUCCESS;
2150
AvahiServerConfig config;
2151
/* Do not publish any local Zeroconf records */
2152
avahi_server_config_init(&config);
2153
config.publish_hinfo = 0;
2154
config.publish_addresses = 0;
2155
config.publish_workstation = 0;
2156
config.publish_domain = 0;
2158
/* Allocate a new server */
2159
mc.server = avahi_server_new(avahi_simple_poll_get
2160
(mc.simple_poll), &config, NULL,
2163
/* Free the Avahi configuration data */
2164
avahi_server_config_free(&config);
2167
/* Check if creating the Avahi server object succeeded */
2168
if(mc.server == NULL){
2169
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2170
avahi_strerror(error));
2171
exitcode = EX_UNAVAILABLE;
2179
/* Create the Avahi service browser */
2180
sb = avahi_s_service_browser_new(mc.server, if_index,
2181
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2182
NULL, 0, browse_callback, NULL);
2184
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2185
avahi_strerror(avahi_server_errno(mc.server)));
2186
exitcode = EX_UNAVAILABLE;
2194
/* Run the main loop */
2197
fprintf_plus(stderr, "Starting Avahi loop search\n");
2200
ret = avahi_loop_with_timeout(mc.simple_poll,
2201
(int)(retry_interval * 1000));
2203
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2204
(ret == 0) ? "successfully" : "with error");
988
fprintf(stderr, "No such interface: \"%s\"\n", interface);
992
if(connect_to != NULL){
993
/* Connect directly, do not use Zeroconf */
994
/* (Mainly meant for debugging) */
995
char *address = strrchr(connect_to, ':');
997
fprintf(stderr, "No colon in address\n");
998
exitcode = EXIT_FAILURE;
1002
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1004
perror("Bad port number");
1005
exitcode = EXIT_FAILURE;
1009
address = connect_to;
1010
ret = start_mandos_communication(address, port, if_index, &mc);
1012
exitcode = EXIT_FAILURE;
1014
exitcode = EXIT_SUCCESS;
1020
avahi_set_log_function(empty_log);
1023
/* Initialize the pseudo-RNG for Avahi */
1024
srand((unsigned int) time(NULL));
1026
/* Allocate main Avahi loop object */
1027
mc.simple_poll = avahi_simple_poll_new();
1028
if (mc.simple_poll == NULL) {
1029
fprintf(stderr, "Avahi: Failed to create simple poll"
1031
exitcode = EXIT_FAILURE;
1036
AvahiServerConfig config;
1037
/* Do not publish any local Zeroconf records */
1038
avahi_server_config_init(&config);
1039
config.publish_hinfo = 0;
1040
config.publish_addresses = 0;
1041
config.publish_workstation = 0;
1042
config.publish_domain = 0;
1044
/* Allocate a new server */
1045
mc.server = avahi_server_new(avahi_simple_poll_get
1046
(mc.simple_poll), &config, NULL,
1049
/* Free the Avahi configuration data */
1050
avahi_server_config_free(&config);
1053
/* Check if creating the Avahi server object succeeded */
1054
if (mc.server == NULL) {
1055
fprintf(stderr, "Failed to create Avahi server: %s\n",
1056
avahi_strerror(error));
1057
exitcode = EXIT_FAILURE;
1061
/* Create the Avahi service browser */
1062
sb = avahi_s_service_browser_new(mc.server, if_index,
1064
"_mandos._tcp", NULL, 0,
1065
browse_callback, &mc);
1067
fprintf(stderr, "Failed to create service browser: %s\n",
1068
avahi_strerror(avahi_server_errno(mc.server)));
1069
exitcode = EXIT_FAILURE;
1073
/* Run the main loop */
1076
fprintf(stderr, "Starting Avahi loop search\n");
1079
avahi_simple_poll_loop(mc.simple_poll);
2210
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2213
/* Cleanup things */
2215
avahi_s_service_browser_free(sb);
2217
if(mc.server != NULL)
2218
avahi_server_free(mc.server);
2220
if(mc.simple_poll != NULL)
2221
avahi_simple_poll_free(mc.simple_poll);
2223
if(gnutls_initialized){
2224
gnutls_certificate_free_credentials(mc.cred);
2225
gnutls_global_deinit();
2226
gnutls_dh_params_deinit(mc.dh_params);
2229
if(gpgme_initialized){
2230
gpgme_release(mc.ctx);
2233
/* Cleans up the circular linked list of Mandos servers the client
2235
if(mc.current_server != NULL){
2236
mc.current_server->prev->next = NULL;
2237
while(mc.current_server != NULL){
2238
server *next = mc.current_server->next;
2239
free(mc.current_server);
2240
mc.current_server = next;
2244
/* Run network hooks */
2245
run_network_hooks("stop", interface, delay);
2247
/* Re-raise priviliges */
2252
perror_plus("seteuid");
2255
/* Take down the network interface */
2256
if(take_down_interface and geteuid() == 0){
2257
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2259
perror_plus("ioctl SIOCGIFFLAGS");
2260
} else if(network.ifr_flags & IFF_UP){
2261
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2262
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2264
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2267
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2269
perror_plus("close");
2273
/* Lower privileges permanently */
2277
perror_plus("setuid");
2280
/* Removes the GPGME temp directory and all files inside */
2281
if(tempdir_created){
2282
struct dirent **direntries = NULL;
2283
struct dirent *direntry = NULL;
2284
int numentries = scandir(tempdir, &direntries, notdotentries,
2286
if (numentries > 0){
2287
for(int i = 0; i < numentries; i++){
2288
direntry = direntries[i];
2289
char *fullname = NULL;
2290
ret = asprintf(&fullname, "%s/%s", tempdir,
2293
perror_plus("asprintf");
2296
ret = remove(fullname);
2298
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2305
/* need to clean even if 0 because man page doesn't specify */
2307
if (numentries == -1){
2308
perror_plus("scandir");
2310
ret = rmdir(tempdir);
2311
if(ret == -1 and errno != ENOENT){
2312
perror_plus("rmdir");
2317
sigemptyset(&old_sigterm_action.sa_mask);
2318
old_sigterm_action.sa_handler = SIG_DFL;
2319
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2320
&old_sigterm_action,
2323
perror_plus("sigaction");
2326
ret = raise(signal_received);
2327
} while(ret != 0 and errno == EINTR);
2329
perror_plus("raise");
2332
TEMP_FAILURE_RETRY(pause());
1084
fprintf(stderr, "%s exiting\n", argv[0]);
1087
/* Cleanup things */
1089
avahi_s_service_browser_free(sb);
1091
if (mc.server != NULL)
1092
avahi_server_free(mc.server);
1094
if (mc.simple_poll != NULL)
1095
avahi_simple_poll_free(mc.simple_poll);
1097
if (gnutls_initalized){
1098
gnutls_certificate_free_credentials(mc.cred);
1099
gnutls_global_deinit ();
1100
gnutls_dh_params_deinit(mc.dh_params);
1103
if(gpgme_initalized){
1104
gpgme_release(mc.ctx);
1107
/* Removes the temp directory used by GPGME */
1108
if(tempdir[0] != '\0'){
1110
struct dirent *direntry;
1111
d = opendir(tempdir);
1116
direntry = readdir(d);
1117
if(direntry == NULL){
1120
if (direntry->d_type == DT_REG){
1121
char *fullname = NULL;
1122
ret = asprintf(&fullname, "%s/%s", tempdir,
1128
ret = unlink(fullname);
1130
fprintf(stderr, "unlink(\"%s\"): %s",
1131
fullname, strerror(errno));
1138
ret = rmdir(tempdir);