497
621
__attribute__((unused)) const char *txt){}
499
623
/* Called when a Mandos server is found */
500
static int start_mandos_communication(const char *ip, uint16_t port,
624
static int start_mandos_communication(const char *ip, in_port_t port,
501
625
AvahiIfIndex if_index,
504
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
627
int ret, tcp_sd = -1;
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
505
633
char *buffer = NULL;
506
char *decrypted_buffer;
634
char *decrypted_buffer = NULL;
507
635
size_t buffer_length = 0;
508
636
size_t buffer_capacity = 0;
509
ssize_t decrypted_buffer_size;
512
char interface[IF_NAMESIZE];
513
639
gnutls_session_t session;
515
ret = init_gnutls_session (mc, &session);
521
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
525
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
532
if(if_indextoname((unsigned int)if_index, interface) == NULL){
533
perror("if_indextoname");
536
fprintf(stderr, "Binding to interface %s\n", interface);
640
int pf; /* Protocol family */
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
662
ret = init_gnutls_session(&session);
668
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
669
PRIuMAX "\n", ip, (uintmax_t)port);
672
tcp_sd = socket(pf, SOCK_STREAM, 0);
675
perror_plus("socket");
539
685
memset(&to, 0, sizeof(to));
540
to.in6.sin6_family = AF_INET6;
541
/* It would be nice to have a way to detect if we were passed an
542
IPv4 address here. Now we assume an IPv6 address. */
543
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
687
to.in6.sin6_family = (sa_family_t)af;
688
ret = inet_pton(af, ip, &to.in6.sin6_addr);
690
to.in.sin_family = (sa_family_t)af;
691
ret = inet_pton(af, ip, &to.in.sin_addr);
695
perror_plus("inet_pton");
549
fprintf(stderr, "Bad address: %s\n", ip);
552
to.in6.sin6_port = htons(port); /* Spurious warning */
701
fprintf_plus(stderr, "Bad address: %s\n", ip);
706
to.in6.sin6_port = htons(port);
707
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
708
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
710
if(if_index == AVAHI_IF_UNSPEC){
711
fprintf_plus(stderr, "An IPv6 link-local address is"
712
" incomplete without a network interface\n");
716
/* Set the network interface number as scope */
717
to.in6.sin6_scope_id = (uint32_t)if_index;
720
to.in.sin_port = htons(port); /* Spurious warnings from
722
-Wunreachable-code */
554
to.in6.sin6_scope_id = (uint32_t)if_index;
557
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
559
char addrstr[INET6_ADDRSTRLEN] = "";
560
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
561
sizeof(addrstr)) == NULL){
731
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
732
char interface[IF_NAMESIZE];
733
if(if_indextoname((unsigned int)if_index, interface) == NULL){
734
perror_plus("if_indextoname");
736
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
737
"\n", ip, interface, (uintmax_t)port);
740
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
741
ip, (uintmax_t)port);
743
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
744
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
747
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
750
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
754
perror_plus("inet_ntop");
564
756
if(strcmp(addrstr, ip) != 0){
565
fprintf(stderr, "Canonical address form: %s\n", addrstr);
757
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
570
ret = connect(tcp_sd, &to.in, sizeof(to));
768
ret = connect(tcp_sd, &to.in6, sizeof(to));
770
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
773
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
775
perror_plus("connect");
576
786
const char *out = mandos_protocol_version;
579
789
size_t out_size = strlen(out);
580
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
581
out_size - written));
790
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
791
out_size - written));
794
perror_plus("write");
587
798
written += (size_t)ret;
588
799
if(written < out_size){
591
if (out == mandos_protocol_version){
802
if(out == mandos_protocol_version){
601
fprintf(stderr, "Establishing TLS session with %s\n", ip);
604
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
607
ret = gnutls_handshake (session);
817
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
825
/* This casting via intptr_t is to eliminate warning about casting
826
an int to a pointer type. This is exactly how the GnuTLS Guile
827
function "set-session-transport-fd!" does it. */
828
gnutls_transport_set_ptr(session,
829
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
837
ret = gnutls_handshake(session);
608
842
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
610
if (ret != GNUTLS_E_SUCCESS){
844
if(ret != GNUTLS_E_SUCCESS){
612
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
846
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
619
853
/* Read OpenPGP packet that contains the wanted password */
622
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
856
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
627
buffer_capacity = adjustbuffer(&buffer, buffer_length,
629
if (buffer_capacity == 0){
630
perror("adjustbuffer");
635
ret = gnutls_record_recv(session, buffer+buffer_length,
867
buffer_capacity = incbuffer(&buffer, buffer_length,
869
if(buffer_capacity == 0){
871
perror_plus("incbuffer");
881
sret = gnutls_record_recv(session, buffer+buffer_length,
642
888
case GNUTLS_E_INTERRUPTED:
643
889
case GNUTLS_E_AGAIN:
645
891
case GNUTLS_E_REHANDSHAKE:
647
ret = gnutls_handshake (session);
893
ret = gnutls_handshake(session);
648
899
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
650
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
901
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
657
fprintf(stderr, "Unknown error while reading data from"
658
" encrypted session with Mandos server\n");
660
gnutls_bye (session, GNUTLS_SHUT_RDWR);
909
fprintf_plus(stderr, "Unknown error while reading data from"
910
" encrypted session with Mandos server\n");
911
gnutls_bye(session, GNUTLS_SHUT_RDWR);
664
buffer_length += (size_t) ret;
916
buffer_length += (size_t) sret;
669
fprintf(stderr, "Closing TLS session\n");
672
gnutls_bye (session, GNUTLS_SHUT_RDWR);
674
if (buffer_length > 0){
675
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
921
fprintf_plus(stderr, "Closing TLS session\n");
930
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
935
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
937
if(buffer_length > 0){
938
ssize_t decrypted_buffer_size;
939
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
677
940
&decrypted_buffer);
678
if (decrypted_buffer_size >= 0){
941
if(decrypted_buffer_size >= 0){
680
944
while(written < (size_t) decrypted_buffer_size){
681
ret = (int)fwrite (decrypted_buffer + written, 1,
682
(size_t)decrypted_buffer_size - written,
950
ret = (int)fwrite(decrypted_buffer + written, 1,
951
(size_t)decrypted_buffer_size - written,
684
953
if(ret == 0 and ferror(stdout)){
686
fprintf(stderr, "Error writing encrypted data: %s\n",
956
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
692
962
written += (size_t)ret;
694
free(decrypted_buffer);
702
968
/* Shutdown procedure */
706
ret = TEMP_FAILURE_RETRY(close(tcp_sd));
973
free(decrypted_buffer);
976
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
982
perror_plus("close");
984
gnutls_deinit(session);
710
gnutls_deinit (session);
714
994
static void resolve_callback(AvahiSServiceResolver *r,
715
995
AvahiIfIndex interface,
716
AVAHI_GCC_UNUSED AvahiProtocol protocol,
717
997
AvahiResolverEvent event,
718
998
const char *name,
719
999
const char *type,
802
1101
case AVAHI_BROWSER_ALL_FOR_NOW:
803
1102
case AVAHI_BROWSER_CACHE_EXHAUSTED:
805
fprintf(stderr, "No Mandos server found, still searching...\n");
1104
fprintf_plus(stderr, "No Mandos server found, still"
1111
/* Signal handler that stops main loop after SIGTERM */
1112
static void handle_sigterm(int sig){
1117
signal_received = sig;
1118
int old_errno = errno;
1119
/* set main loop to exit */
1120
if(mc.simple_poll != NULL){
1121
avahi_simple_poll_quit(mc.simple_poll);
1126
bool get_flags(const char *ifname, struct ifreq *ifr){
1130
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1133
perror_plus("socket");
1137
strcpy(ifr->ifr_name, ifname);
1138
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1142
perror_plus("ioctl SIOCGIFFLAGS");
1150
bool good_flags(const char *ifname, const struct ifreq *ifr){
1152
/* Reject the loopback device */
1153
if(ifr->ifr_flags & IFF_LOOPBACK){
1155
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1163
fprintf_plus(stderr, "Accepting point-to-point interface"
1164
" \"%s\"\n", ifname);
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1171
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1172
" \"%s\"\n", ifname);
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(ifr->ifr_flags & IFF_NOARP){
1179
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1185
/* Accept this device */
1187
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1193
* This function determines if a directory entry in /sys/class/net
1194
* corresponds to an acceptable network device.
1195
* (This function is passed to scandir(3) as a filter function.)
1197
int good_interface(const struct dirent *if_entry){
1198
if(if_entry->d_name[0] == '.'){
1203
if(not get_flags(if_entry->d_name, &ifr)){
1205
fprintf_plus(stderr, "Failed to get flags for interface "
1206
"\"%s\"\n", if_entry->d_name);
1211
if(not good_flags(if_entry->d_name, &ifr)){
1218
* This function determines if a network interface is up.
1220
bool interface_is_up(const char *interface){
1222
if(not get_flags(interface, &ifr)){
1224
fprintf_plus(stderr, "Failed to get flags for interface "
1225
"\"%s\"\n", interface);
1230
return (bool)(ifr.ifr_flags & IFF_UP);
1234
* This function determines if a network interface is running
1236
bool interface_is_running(const char *interface){
1238
if(not get_flags(interface, &ifr)){
1240
fprintf_plus(stderr, "Failed to get flags for interface "
1241
"\"%s\"\n", interface);
1246
return (bool)(ifr.ifr_flags & IFF_RUNNING);
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
/* Set effective uid to 0, return errno */
1394
error_t raise_privileges(void){
1395
error_t old_errno = errno;
1396
error_t ret_errno = 0;
1397
if(seteuid(0) == -1){
1399
perror_plus("seteuid");
1405
/* Set effective and real user ID to 0. Return errno. */
1406
error_t raise_privileges_permanently(void){
1407
error_t old_errno = errno;
1408
error_t ret_errno = raise_privileges();
1413
if(setuid(0) == -1){
1415
perror_plus("seteuid");
1421
/* Set effective user ID to unprivileged saved user ID */
1422
error_t lower_privileges(void){
1423
error_t old_errno = errno;
1424
error_t ret_errno = 0;
1425
if(seteuid(uid) == -1){
1427
perror_plus("seteuid");
1433
/* Lower privileges permanently */
1434
error_t lower_privileges_permanently(void){
1435
error_t old_errno = errno;
1436
error_t ret_errno = 0;
1437
if(setuid(uid) == -1){
1439
perror_plus("setuid");
1445
bool run_network_hooks(const char *mode, const char *interface,
1447
struct dirent **direntries;
1448
struct dirent *direntry;
1450
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1453
if(errno == ENOENT){
1455
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1456
" found\n", hookdir);
1459
perror_plus("scandir");
1462
int devnull = open("/dev/null", O_RDONLY);
1463
for(int i = 0; i < numhooks; i++){
1464
direntry = direntries[i];
1465
char *fullname = NULL;
1466
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1468
perror_plus("asprintf");
1472
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1475
pid_t hook_pid = fork();
1478
/* Raise privileges */
1479
raise_privileges_permanently();
1484
perror_plus("setgid");
1486
/* Reset supplementary groups */
1488
ret = setgroups(0, NULL);
1490
perror_plus("setgroups");
1492
dup2(devnull, STDIN_FILENO);
1494
dup2(STDERR_FILENO, STDOUT_FILENO);
1495
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1497
perror_plus("setenv");
1500
ret = setenv("DEVICE", interface, 1);
1502
perror_plus("setenv");
1505
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1507
perror_plus("setenv");
1510
ret = setenv("MODE", mode, 1);
1512
perror_plus("setenv");
1516
ret = asprintf(&delaystring, "%f", delay);
1518
perror_plus("asprintf");
1521
ret = setenv("DELAY", delaystring, 1);
1524
perror_plus("setenv");
1528
if(connect_to != NULL){
1529
ret = setenv("CONNECT", connect_to, 1);
1531
perror_plus("setenv");
1535
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1536
perror_plus("execl");
1537
_exit(EXIT_FAILURE);
1541
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1542
perror_plus("waitpid");
1546
if(WIFEXITED(status)){
1547
if(WEXITSTATUS(status) != 0){
1548
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1549
" with status %d\n", direntry->d_name,
1550
WEXITSTATUS(status));
1554
} else if(WIFSIGNALED(status)){
1555
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1556
" signal %d\n", direntry->d_name,
1561
fprintf_plus(stderr, "Warning: network hook \"%s\""
1562
" crashed\n", direntry->d_name);
1569
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1578
error_t bring_up_interface(const char *const interface,
1581
error_t old_errno = errno;
1582
error_t ret_errno = 0;
1583
int ret, ret_setflags;
1584
struct ifreq network;
1585
unsigned int if_index = if_nametoindex(interface);
1587
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1597
if(not interface_is_up(interface)){
1598
if(not get_flags(interface, &network) and debug){
1600
fprintf_plus(stderr, "Failed to get flags for interface "
1601
"\"%s\"\n", interface);
1604
network.ifr_flags |= IFF_UP;
1606
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1609
perror_plus("socket");
1621
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1625
/* Raise priviliges */
1629
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1630
messages about the network interface to mess up the prompt */
1631
int ret_linux = klogctl(8, NULL, 5);
1632
bool restore_loglevel = true;
1633
if(ret_linux == -1){
1634
restore_loglevel = false;
1635
perror_plus("klogctl");
1637
#endif /* __linux__ */
1638
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1641
if(restore_loglevel){
1642
ret_linux = klogctl(7, NULL, 0);
1643
if(ret_linux == -1){
1644
perror_plus("klogctl");
1647
#endif /* __linux__ */
1649
/* Lower privileges */
1652
/* Close the socket */
1653
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1655
perror_plus("close");
1658
if(ret_setflags == -1){
1660
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1665
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1669
/* Sleep checking until interface is running.
1670
Check every 0.25s, up to total time of delay */
1671
for(int i=0; i < delay * 4; i++){
1672
if(interface_is_running(interface)){
1675
struct timespec sleeptime = { .tv_nsec = 250000000 };
1676
ret = nanosleep(&sleeptime, NULL);
1677
if(ret == -1 and errno != EINTR){
1678
perror_plus("nanosleep");
1686
error_t take_down_interface(const char *const interface){
1688
error_t old_errno = errno;
1689
error_t ret_errno = 0;
1690
int ret, ret_setflags;
1691
struct ifreq network;
1692
unsigned int if_index = if_nametoindex(interface);
1694
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1698
if(interface_is_up(interface)){
1699
if(not get_flags(interface, &network) and debug){
1701
fprintf_plus(stderr, "Failed to get flags for interface "
1702
"\"%s\"\n", interface);
1705
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1707
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1710
perror_plus("socket");
1716
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1720
/* Raise priviliges */
1723
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1726
/* Lower privileges */
1729
/* Close the socket */
1730
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1732
perror_plus("close");
1735
if(ret_setflags == -1){
1737
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1742
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
811
1750
int main(int argc, char *argv[]){
812
AvahiSServiceBrowser *sb = NULL;
815
int exitcode = EXIT_SUCCESS;
816
const char *interface = "eth0";
817
struct ifreq network;
821
char *connect_to = NULL;
822
char tempdir[] = "/tmp/mandosXXXXXX";
823
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
824
const char *seckey = PATHDIR "/" SECKEY;
825
const char *pubkey = PATHDIR "/" PUBKEY;
827
mandos_context mc = { .simple_poll = NULL, .server = NULL,
828
.dh_bits = 1024, .priority = "SECURE256"
829
":!CTYPE-X.509:+CTYPE-OPENPGP" };
830
bool gnutls_initalized = false;
831
bool gpgme_initalized = false;
834
struct argp_option options[] = {
835
{ .name = "debug", .key = 128,
836
.doc = "Debug mode", .group = 3 },
837
{ .name = "connect", .key = 'c',
838
.arg = "ADDRESS:PORT",
839
.doc = "Connect directly to a specific Mandos server",
841
{ .name = "interface", .key = 'i',
843
.doc = "Interface that will be used to search for Mandos"
846
{ .name = "seckey", .key = 's',
848
.doc = "OpenPGP secret key file base name",
850
{ .name = "pubkey", .key = 'p',
852
.doc = "OpenPGP public key file base name",
854
{ .name = "dh-bits", .key = 129,
856
.doc = "Bit length of the prime number used in the"
857
" Diffie-Hellman key exchange",
859
{ .name = "priority", .key = 130,
861
.doc = "GnuTLS priority string for the TLS handshake",
866
error_t parse_opt (int key, char *arg,
867
struct argp_state *state) {
868
/* Get the INPUT argument from `argp_parse', which we know is
869
a pointer to our plugin list pointer. */
871
case 128: /* --debug */
874
case 'c': /* --connect */
877
case 'i': /* --interface */
880
case 's': /* --seckey */
883
case 'p': /* --pubkey */
886
case 129: /* --dh-bits */
888
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
894
case 130: /* --priority */
902
return ARGP_ERR_UNKNOWN;
907
struct argp argp = { .options = options, .parser = parse_opt,
909
.doc = "Mandos client -- Get and decrypt"
910
" passwords from a Mandos server" };
911
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
912
if (ret == ARGP_ERR_UNKNOWN){
913
fprintf(stderr, "Unknown error while parsing arguments\n");
914
exitcode = EXIT_FAILURE;
919
/* If the interface is down, bring it up */
921
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
924
exitcode = EXIT_FAILURE;
927
strcpy(network.ifr_name, interface);
928
ret = ioctl(sd, SIOCGIFFLAGS, &network);
930
perror("ioctl SIOCGIFFLAGS");
931
exitcode = EXIT_FAILURE;
934
if((network.ifr_flags & IFF_UP) == 0){
935
network.ifr_flags |= IFF_UP;
936
ret = ioctl(sd, SIOCSIFFLAGS, &network);
938
perror("ioctl SIOCSIFFLAGS");
939
exitcode = EXIT_FAILURE;
943
ret = TEMP_FAILURE_RETRY(close(sd));
962
ret = init_gnutls_global(&mc, pubkey, seckey);
964
fprintf(stderr, "init_gnutls_global failed\n");
965
exitcode = EXIT_FAILURE;
968
gnutls_initalized = true;
971
if(mkdtemp(tempdir) == NULL){
977
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
978
fprintf(stderr, "gpgme_initalized failed\n");
979
exitcode = EXIT_FAILURE;
982
gpgme_initalized = true;
985
if_index = (AvahiIfIndex) if_nametoindex(interface);
987
fprintf(stderr, "No such interface: \"%s\"\n", interface);
991
if(connect_to != NULL){
992
/* Connect directly, do not use Zeroconf */
993
/* (Mainly meant for debugging) */
994
char *address = strrchr(connect_to, ':');
996
fprintf(stderr, "No colon in address\n");
997
exitcode = EXIT_FAILURE;
1001
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1003
perror("Bad port number");
1004
exitcode = EXIT_FAILURE;
1008
address = connect_to;
1009
ret = start_mandos_communication(address, port, if_index, &mc);
1011
exitcode = EXIT_FAILURE;
1013
exitcode = EXIT_SUCCESS;
1019
avahi_set_log_function(empty_log);
1022
/* Initialize the pseudo-RNG for Avahi */
1023
srand((unsigned int) time(NULL));
1025
/* Allocate main Avahi loop object */
1026
mc.simple_poll = avahi_simple_poll_new();
1027
if (mc.simple_poll == NULL) {
1028
fprintf(stderr, "Avahi: Failed to create simple poll"
1030
exitcode = EXIT_FAILURE;
1035
AvahiServerConfig config;
1036
/* Do not publish any local Zeroconf records */
1037
avahi_server_config_init(&config);
1038
config.publish_hinfo = 0;
1039
config.publish_addresses = 0;
1040
config.publish_workstation = 0;
1041
config.publish_domain = 0;
1043
/* Allocate a new server */
1044
mc.server = avahi_server_new(avahi_simple_poll_get
1045
(mc.simple_poll), &config, NULL,
1048
/* Free the Avahi configuration data */
1049
avahi_server_config_free(&config);
1052
/* Check if creating the Avahi server object succeeded */
1053
if (mc.server == NULL) {
1054
fprintf(stderr, "Failed to create Avahi server: %s\n",
1055
avahi_strerror(error));
1056
exitcode = EXIT_FAILURE;
1060
/* Create the Avahi service browser */
1061
sb = avahi_s_service_browser_new(mc.server, if_index,
1063
"_mandos._tcp", NULL, 0,
1064
browse_callback, &mc);
1066
fprintf(stderr, "Failed to create service browser: %s\n",
1067
avahi_strerror(avahi_server_errno(mc.server)));
1068
exitcode = EXIT_FAILURE;
1072
/* Run the main loop */
1075
fprintf(stderr, "Starting Avahi loop search\n");
1078
avahi_simple_poll_loop(mc.simple_poll);
1751
AvahiSServiceBrowser *sb = NULL;
1756
int exitcode = EXIT_SUCCESS;
1757
char *interfaces = NULL;
1758
size_t interfaces_size = 0;
1759
char *interfaces_to_take_down = NULL;
1760
size_t interfaces_to_take_down_size = 0;
1761
char tempdir[] = "/tmp/mandosXXXXXX";
1762
bool tempdir_created = false;
1763
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1764
const char *seckey = PATHDIR "/" SECKEY;
1765
const char *pubkey = PATHDIR "/" PUBKEY;
1766
char *interfaces_hooks = NULL;
1767
size_t interfaces_hooks_size = 0;
1769
bool gnutls_initialized = false;
1770
bool gpgme_initialized = false;
1772
double retry_interval = 10; /* 10s between trying a server and
1773
retrying the same server again */
1775
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1776
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1781
/* Lower any group privileges we might have, just to be safe */
1785
perror_plus("setgid");
1788
/* Lower user privileges (temporarily) */
1792
perror_plus("seteuid");
1800
struct argp_option options[] = {
1801
{ .name = "debug", .key = 128,
1802
.doc = "Debug mode", .group = 3 },
1803
{ .name = "connect", .key = 'c',
1804
.arg = "ADDRESS:PORT",
1805
.doc = "Connect directly to a specific Mandos server",
1807
{ .name = "interface", .key = 'i',
1809
.doc = "Network interface that will be used to search for"
1812
{ .name = "seckey", .key = 's',
1814
.doc = "OpenPGP secret key file base name",
1816
{ .name = "pubkey", .key = 'p',
1818
.doc = "OpenPGP public key file base name",
1820
{ .name = "dh-bits", .key = 129,
1822
.doc = "Bit length of the prime number used in the"
1823
" Diffie-Hellman key exchange",
1825
{ .name = "priority", .key = 130,
1827
.doc = "GnuTLS priority string for the TLS handshake",
1829
{ .name = "delay", .key = 131,
1831
.doc = "Maximum delay to wait for interface startup",
1833
{ .name = "retry", .key = 132,
1835
.doc = "Retry interval used when denied by the Mandos server",
1837
{ .name = "network-hook-dir", .key = 133,
1839
.doc = "Directory where network hooks are located",
1842
* These reproduce what we would get without ARGP_NO_HELP
1844
{ .name = "help", .key = '?',
1845
.doc = "Give this help list", .group = -1 },
1846
{ .name = "usage", .key = -3,
1847
.doc = "Give a short usage message", .group = -1 },
1848
{ .name = "version", .key = 'V',
1849
.doc = "Print program version", .group = -1 },
1853
error_t parse_opt(int key, char *arg,
1854
struct argp_state *state){
1857
case 128: /* --debug */
1860
case 'c': /* --connect */
1863
case 'i': /* --interface */
1864
ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,
1867
argp_error(state, "%s", strerror(ret_errno));
1870
case 's': /* --seckey */
1873
case 'p': /* --pubkey */
1876
case 129: /* --dh-bits */
1878
tmpmax = strtoimax(arg, &tmp, 10);
1879
if(errno != 0 or tmp == arg or *tmp != '\0'
1880
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1881
argp_error(state, "Bad number of DH bits");
1883
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1885
case 130: /* --priority */
1888
case 131: /* --delay */
1890
delay = strtof(arg, &tmp);
1891
if(errno != 0 or tmp == arg or *tmp != '\0'){
1892
argp_error(state, "Bad delay");
1894
case 132: /* --retry */
1896
retry_interval = strtod(arg, &tmp);
1897
if(errno != 0 or tmp == arg or *tmp != '\0'
1898
or (retry_interval * 1000) > INT_MAX
1899
or retry_interval < 0){
1900
argp_error(state, "Bad retry interval");
1903
case 133: /* --network-hook-dir */
1907
* These reproduce what we would get without ARGP_NO_HELP
1909
case '?': /* --help */
1910
argp_state_help(state, state->out_stream,
1911
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1912
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1913
case -3: /* --usage */
1914
argp_state_help(state, state->out_stream,
1915
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1916
case 'V': /* --version */
1917
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1918
exit(argp_err_exit_status);
1921
return ARGP_ERR_UNKNOWN;
1926
struct argp argp = { .options = options, .parser = parse_opt,
1928
.doc = "Mandos client -- Get and decrypt"
1929
" passwords from a Mandos server" };
1930
ret = argp_parse(&argp, argc, argv,
1931
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1938
perror_plus("argp_parse");
1939
exitcode = EX_OSERR;
1942
exitcode = EX_USAGE;
1948
/* Work around Debian bug #633582:
1949
<http://bugs.debian.org/633582> */
1951
/* Re-raise priviliges */
1952
if(raise_privileges() == 0){
1955
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1956
int seckey_fd = open(seckey, O_RDONLY);
1957
if(seckey_fd == -1){
1958
perror_plus("open");
1960
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1962
perror_plus("fstat");
1964
if(S_ISREG(st.st_mode)
1965
and st.st_uid == 0 and st.st_gid == 0){
1966
ret = fchown(seckey_fd, uid, gid);
1968
perror_plus("fchown");
1972
TEMP_FAILURE_RETRY(close(seckey_fd));
1976
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1977
int pubkey_fd = open(pubkey, O_RDONLY);
1978
if(pubkey_fd == -1){
1979
perror_plus("open");
1981
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1983
perror_plus("fstat");
1985
if(S_ISREG(st.st_mode)
1986
and st.st_uid == 0 and st.st_gid == 0){
1987
ret = fchown(pubkey_fd, uid, gid);
1989
perror_plus("fchown");
1993
TEMP_FAILURE_RETRY(close(pubkey_fd));
1997
/* Lower privileges */
2001
perror_plus("seteuid");
2006
/* Remove empty interface names */
2008
char *interface = NULL;
2009
while((interface = argz_next(interfaces, interfaces_size,
2011
if(if_nametoindex(interface) == 0){
2012
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2013
fprintf_plus(stderr, "Not using nonexisting interface"
2014
" \"%s\"\n", interface);
2016
argz_delete(&interfaces, &interfaces_size, interface);
2022
/* Run network hooks */
2024
ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,
2025
interfaces, interfaces_size);
2028
perror_plus("argz_append");
2031
argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');
2032
if(not run_network_hooks("start", interfaces_hooks, delay)){
2038
avahi_set_log_function(empty_log);
2041
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2042
from the signal handler */
2043
/* Initialize the pseudo-RNG for Avahi */
2044
srand((unsigned int) time(NULL));
2045
mc.simple_poll = avahi_simple_poll_new();
2046
if(mc.simple_poll == NULL){
2047
fprintf_plus(stderr,
2048
"Avahi: Failed to create simple poll object.\n");
2049
exitcode = EX_UNAVAILABLE;
2053
sigemptyset(&sigterm_action.sa_mask);
2054
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2056
perror_plus("sigaddset");
2057
exitcode = EX_OSERR;
2060
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2062
perror_plus("sigaddset");
2063
exitcode = EX_OSERR;
2066
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2068
perror_plus("sigaddset");
2069
exitcode = EX_OSERR;
2072
/* Need to check if the handler is SIG_IGN before handling:
2073
| [[info:libc:Initial Signal Actions]] |
2074
| [[info:libc:Basic Signal Handling]] |
2076
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2078
perror_plus("sigaction");
2081
if(old_sigterm_action.sa_handler != SIG_IGN){
2082
ret = sigaction(SIGINT, &sigterm_action, NULL);
2084
perror_plus("sigaction");
2085
exitcode = EX_OSERR;
2089
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2091
perror_plus("sigaction");
2094
if(old_sigterm_action.sa_handler != SIG_IGN){
2095
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2097
perror_plus("sigaction");
2098
exitcode = EX_OSERR;
2102
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2104
perror_plus("sigaction");
2107
if(old_sigterm_action.sa_handler != SIG_IGN){
2108
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2110
perror_plus("sigaction");
2111
exitcode = EX_OSERR;
2116
/* If no interfaces were specified, make a list */
2117
if(interfaces == NULL){
2118
struct dirent **direntries;
2119
/* Look for any good interfaces */
2120
ret = scandir(sys_class_net, &direntries, good_interface,
2123
/* Add all found interfaces to interfaces list */
2124
for(int i = 0; i < ret; ++i){
2125
ret_errno = argz_add(&interfaces, &interfaces_size,
2126
direntries[i]->d_name);
2128
perror_plus("argz_add");
2132
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2133
direntries[i]->d_name);
2139
fprintf_plus(stderr, "Could not find a network interface\n");
2140
exitcode = EXIT_FAILURE;
2145
/* If we only got one interface, explicitly use only that one */
2146
if(argz_count(interfaces, interfaces_size) == 1){
2148
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2151
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2154
/* Bring up interfaces which are down */
2155
if(not (argz_count(interfaces, interfaces_size) == 1
2156
and strcmp(interfaces, "none") == 0)){
2157
char *interface = NULL;
2158
while((interface = argz_next(interfaces, interfaces_size,
2160
bool interface_was_up = interface_is_up(interface);
2161
ret = bring_up_interface(interface, delay);
2162
if(not interface_was_up){
2165
perror_plus("Failed to bring up interface");
2167
ret_errno = argz_add(&interfaces_to_take_down,
2168
&interfaces_to_take_down_size,
2175
interfaces_size = 0;
2176
if(debug and (interfaces_to_take_down == NULL)){
2177
fprintf_plus(stderr, "No interfaces were brought up\n");
2185
ret = init_gnutls_global(pubkey, seckey);
2187
fprintf_plus(stderr, "init_gnutls_global failed\n");
2188
exitcode = EX_UNAVAILABLE;
2191
gnutls_initialized = true;
2198
if(mkdtemp(tempdir) == NULL){
2199
perror_plus("mkdtemp");
2202
tempdir_created = true;
2208
if(not init_gpgme(pubkey, seckey, tempdir)){
2209
fprintf_plus(stderr, "init_gpgme failed\n");
2210
exitcode = EX_UNAVAILABLE;
2213
gpgme_initialized = true;
2220
if(connect_to != NULL){
2221
/* Connect directly, do not use Zeroconf */
2222
/* (Mainly meant for debugging) */
2223
char *address = strrchr(connect_to, ':');
2225
if(address == NULL){
2226
fprintf_plus(stderr, "No colon in address\n");
2227
exitcode = EX_USAGE;
2237
tmpmax = strtoimax(address+1, &tmp, 10);
2238
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2239
or tmpmax != (in_port_t)tmpmax){
2240
fprintf_plus(stderr, "Bad port number\n");
2241
exitcode = EX_USAGE;
2249
port = (in_port_t)tmpmax;
2251
/* Colon in address indicates IPv6 */
2253
if(strchr(connect_to, ':') != NULL){
2255
/* Accept [] around IPv6 address - see RFC 5952 */
2256
if(connect_to[0] == '[' and address[-1] == ']')
2264
address = connect_to;
2270
while(not quit_now){
2271
ret = start_mandos_communication(address, port, if_index, af);
2272
if(quit_now or ret == 0){
2276
fprintf_plus(stderr, "Retrying in %d seconds\n",
2277
(int)retry_interval);
2279
sleep((int)retry_interval);
2283
exitcode = EXIT_SUCCESS;
2294
AvahiServerConfig config;
2295
/* Do not publish any local Zeroconf records */
2296
avahi_server_config_init(&config);
2297
config.publish_hinfo = 0;
2298
config.publish_addresses = 0;
2299
config.publish_workstation = 0;
2300
config.publish_domain = 0;
2302
/* Allocate a new server */
2303
mc.server = avahi_server_new(avahi_simple_poll_get
2304
(mc.simple_poll), &config, NULL,
2307
/* Free the Avahi configuration data */
2308
avahi_server_config_free(&config);
2311
/* Check if creating the Avahi server object succeeded */
2312
if(mc.server == NULL){
2313
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2314
avahi_strerror(ret_errno));
2315
exitcode = EX_UNAVAILABLE;
2323
/* Create the Avahi service browser */
2324
sb = avahi_s_service_browser_new(mc.server, if_index,
2325
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2326
NULL, 0, browse_callback, NULL);
2328
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2329
avahi_strerror(avahi_server_errno(mc.server)));
2330
exitcode = EX_UNAVAILABLE;
2338
/* Run the main loop */
2341
fprintf_plus(stderr, "Starting Avahi loop search\n");
2344
ret = avahi_loop_with_timeout(mc.simple_poll,
2345
(int)(retry_interval * 1000));
2347
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2348
(ret == 0) ? "successfully" : "with error");
1083
fprintf(stderr, "%s exiting\n", argv[0]);
1086
/* Cleanup things */
1088
avahi_s_service_browser_free(sb);
1090
if (mc.server != NULL)
1091
avahi_server_free(mc.server);
1093
if (mc.simple_poll != NULL)
1094
avahi_simple_poll_free(mc.simple_poll);
1096
if (gnutls_initalized){
1097
gnutls_certificate_free_credentials(mc.cred);
1098
gnutls_global_deinit ();
1099
gnutls_dh_params_deinit(mc.dh_params);
1102
if(gpgme_initalized){
1103
gpgme_release(mc.ctx);
1106
/* Removes the temp directory used by GPGME */
1107
if(tempdir[0] != '\0'){
1109
struct dirent *direntry;
1110
d = opendir(tempdir);
1115
direntry = readdir(d);
1116
if(direntry == NULL){
1119
if (direntry->d_type == DT_REG){
1120
char *fullname = NULL;
1121
ret = asprintf(&fullname, "%s/%s", tempdir,
1127
ret = unlink(fullname);
1129
fprintf(stderr, "unlink(\"%s\"): %s",
1130
fullname, strerror(errno));
1137
ret = rmdir(tempdir);
2354
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2357
/* Cleanup things */
2359
avahi_s_service_browser_free(sb);
2361
if(mc.server != NULL)
2362
avahi_server_free(mc.server);
2364
if(mc.simple_poll != NULL)
2365
avahi_simple_poll_free(mc.simple_poll);
2367
if(gnutls_initialized){
2368
gnutls_certificate_free_credentials(mc.cred);
2369
gnutls_global_deinit();
2370
gnutls_dh_params_deinit(mc.dh_params);
2373
if(gpgme_initialized){
2374
gpgme_release(mc.ctx);
2377
/* Cleans up the circular linked list of Mandos servers the client
2379
if(mc.current_server != NULL){
2380
mc.current_server->prev->next = NULL;
2381
while(mc.current_server != NULL){
2382
server *next = mc.current_server->next;
2383
free(mc.current_server);
2384
mc.current_server = next;
2388
/* Re-raise priviliges */
2392
/* Run network hooks */
2393
run_network_hooks("stop", interfaces_hooks, delay);
2395
/* Take down the network interfaces which were brought up */
2397
char *interface = NULL;
2398
while((interface=argz_next(interfaces_to_take_down,
2399
interfaces_to_take_down_size,
2401
ret_errno = take_down_interface(interface);
2404
perror_plus("Failed to take down interface");
2407
if(debug and (interfaces_to_take_down == NULL)){
2408
fprintf_plus(stderr, "No interfaces needed to be taken"
2413
lower_privileges_permanently();
2416
free(interfaces_to_take_down);
2417
free(interfaces_hooks);
2419
/* Removes the GPGME temp directory and all files inside */
2420
if(tempdir_created){
2421
struct dirent **direntries = NULL;
2422
struct dirent *direntry = NULL;
2423
int numentries = scandir(tempdir, &direntries, notdotentries,
2425
if (numentries > 0){
2426
for(int i = 0; i < numentries; i++){
2427
direntry = direntries[i];
2428
char *fullname = NULL;
2429
ret = asprintf(&fullname, "%s/%s", tempdir,
2432
perror_plus("asprintf");
2435
ret = remove(fullname);
2437
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2444
/* need to clean even if 0 because man page doesn't specify */
2446
if (numentries == -1){
2447
perror_plus("scandir");
2449
ret = rmdir(tempdir);
2450
if(ret == -1 and errno != ENOENT){
2451
perror_plus("rmdir");
2456
sigemptyset(&old_sigterm_action.sa_mask);
2457
old_sigterm_action.sa_handler = SIG_DFL;
2458
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2459
&old_sigterm_action,
2462
perror_plus("sigaction");
2465
ret = raise(signal_received);
2466
} while(ret != 0 and errno == EINTR);
2468
perror_plus("raise");
2471
TEMP_FAILURE_RETRY(pause());