224
232
/* Special case of first server */
225
if (mc.current_server == NULL){
233
if(*current_server == NULL){
226
234
new_server->next = new_server;
227
235
new_server->prev = new_server;
228
mc.current_server = new_server;
236
*current_server = new_server;
229
237
/* Place the new server last in the list */
231
new_server->next = mc.current_server;
232
new_server->prev = mc.current_server->prev;
239
new_server->next = *current_server;
240
new_server->prev = (*current_server)->prev;
233
241
new_server->prev->next = new_server;
234
mc.current_server->prev = new_server;
242
(*current_server)->prev = new_server;
236
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
244
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
238
246
perror_plus("clock_gettime");
532
540
/* GnuTLS server initialization */
533
ret = gnutls_dh_params_init(&mc.dh_params);
541
ret = gnutls_dh_params_init(&mc->dh_params);
534
542
if(ret != GNUTLS_E_SUCCESS){
535
543
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
536
544
" initialization: %s\n",
537
545
safer_gnutls_strerror(ret));
540
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
548
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
541
549
if(ret != GNUTLS_E_SUCCESS){
542
550
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
543
551
safer_gnutls_strerror(ret));
547
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
555
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
553
gnutls_certificate_free_credentials(mc.cred);
561
gnutls_certificate_free_credentials(mc->cred);
554
562
gnutls_global_deinit();
555
gnutls_dh_params_deinit(mc.dh_params);
563
gnutls_dh_params_deinit(mc->dh_params);
559
static int init_gnutls_session(gnutls_session_t *session){
567
static int init_gnutls_session(gnutls_session_t *session,
561
570
/* GnuTLS session creation */
658
ret = init_gnutls_session(&session);
667
/* If the interface is specified and we have a list of interfaces */
668
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
669
/* Check if the interface is one of the interfaces we are using */
672
char *interface = NULL;
673
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
675
if(if_nametoindex(interface) == (unsigned int)if_index){
682
/* This interface does not match any in the list, so we don't
683
connect to the server */
685
char interface[IF_NAMESIZE];
686
if(if_indextoname((unsigned int)if_index, interface) == NULL){
687
perror_plus("if_indextoname");
689
fprintf_plus(stderr, "Skipping server on non-used interface"
691
if_indextoname((unsigned int)if_index,
699
ret = init_gnutls_session(&session, mc);
664
705
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
665
PRIu16 "\n", ip, port);
706
PRIuMAX "\n", ip, (uintmax_t)port);
668
709
tcp_sd = socket(pf, SOCK_STREAM, 0);
732
774
if(if_indextoname((unsigned int)if_index, interface) == NULL){
733
775
perror_plus("if_indextoname");
735
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
736
"\n", ip, interface, port);
777
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
778
"\n", ip, interface, (uintmax_t)port);
739
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
781
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
782
ip, (uintmax_t)port);
742
784
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
743
785
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1028
1076
PRIdMAX ") on port %" PRIu16 "\n", name,
1029
1077
host_name, ip, (intmax_t)interface, port);
1031
int ret = start_mandos_communication(ip, port, interface,
1032
avahi_proto_to_af(proto));
1079
int ret = start_mandos_communication(ip, (in_port_t)port,
1081
avahi_proto_to_af(proto),
1034
avahi_simple_poll_quit(mc.simple_poll);
1084
avahi_simple_poll_quit(simple_poll);
1036
if(not add_server(ip, port, interface,
1037
avahi_proto_to_af(proto))){
1086
if(not add_server(ip, (in_port_t)port, interface,
1087
avahi_proto_to_af(proto),
1088
&((mandos_context*)mc)->current_server)){
1038
1089
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1039
1090
" list\n", name);
1078
1132
the callback function is called the Avahi server will free the
1079
1133
resolver for us. */
1081
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1082
name, type, domain, protocol, 0,
1083
resolve_callback, NULL) == NULL)
1135
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1136
interface, protocol, name, type,
1137
domain, protocol, 0,
1138
resolve_callback, mc) == NULL)
1084
1139
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1086
avahi_strerror(avahi_server_errno(mc.server)));
1141
avahi_strerror(avahi_server_errno
1142
(((mandos_context*)mc)->server)));
1089
1145
case AVAHI_BROWSER_REMOVE:
1204
* This function determines if a directory entry in /sys/class/net
1205
* corresponds to an acceptable network device which is up.
1206
* (This function is passed to scandir(3) as a filter function.)
1208
int up_interface(const struct dirent *if_entry){
1209
if(if_entry->d_name[0] == '.'){
1214
if(not get_flags(if_entry->d_name, &ifr)){
1216
fprintf_plus(stderr, "Failed to get flags for interface "
1217
"\"%s\"\n", if_entry->d_name);
1222
/* Reject down interfaces */
1223
if(not (ifr.ifr_flags & IFF_UP)){
1225
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1231
/* Reject non-running interfaces */
1232
if(not (ifr.ifr_flags & IFF_RUNNING)){
1234
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1240
if(not good_flags(if_entry->d_name, &ifr)){
1265
* This function determines if a network interface is up.
1267
bool interface_is_up(const char *interface){
1269
if(not get_flags(interface, &ifr)){
1271
fprintf_plus(stderr, "Failed to get flags for interface "
1272
"\"%s\"\n", interface);
1277
return (bool)(ifr.ifr_flags & IFF_UP);
1281
* This function determines if a network interface is running
1283
bool interface_is_running(const char *interface){
1285
if(not get_flags(interface, &ifr)){
1287
fprintf_plus(stderr, "Failed to get flags for interface "
1288
"\"%s\"\n", interface);
1293
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1246
1296
int notdotentries(const struct dirent *direntry){
1360
1411
if(block_time <= 0){
1361
ret = start_mandos_communication(mc.current_server->ip,
1362
mc.current_server->port,
1363
mc.current_server->if_index,
1364
mc.current_server->af);
1412
ret = start_mandos_communication(mc->current_server->ip,
1413
mc->current_server->port,
1414
mc->current_server->if_index,
1415
mc->current_server->af, mc);
1366
avahi_simple_poll_quit(mc.simple_poll);
1417
avahi_simple_poll_quit(s);
1369
1420
ret = clock_gettime(CLOCK_MONOTONIC,
1370
&mc.current_server->last_seen);
1421
&mc->current_server->last_seen);
1372
1423
perror_plus("clock_gettime");
1375
mc.current_server = mc.current_server->next;
1426
mc->current_server = mc->current_server->next;
1376
1427
block_time = 0; /* Call avahi to find new Mandos
1377
1428
servers, but don't block */
1441
/* Set effective uid to 0, return errno */
1442
error_t raise_privileges(void){
1443
error_t old_errno = errno;
1444
error_t ret_errno = 0;
1445
if(seteuid(0) == -1){
1447
perror_plus("seteuid");
1453
/* Set effective and real user ID to 0. Return errno. */
1454
error_t raise_privileges_permanently(void){
1455
error_t old_errno = errno;
1456
error_t ret_errno = raise_privileges();
1461
if(setuid(0) == -1){
1463
perror_plus("seteuid");
1469
/* Set effective user ID to unprivileged saved user ID */
1470
error_t lower_privileges(void){
1471
error_t old_errno = errno;
1472
error_t ret_errno = 0;
1473
if(seteuid(uid) == -1){
1475
perror_plus("seteuid");
1481
/* Lower privileges permanently */
1482
error_t lower_privileges_permanently(void){
1483
error_t old_errno = errno;
1484
error_t ret_errno = 0;
1485
if(setuid(uid) == -1){
1487
perror_plus("setuid");
1390
1493
bool run_network_hooks(const char *mode, const char *interface,
1391
1494
const float delay){
1392
1495
struct dirent **direntries;
1393
struct dirent *direntry;
1395
1496
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1397
1498
if(numhooks == -1){
1398
perror_plus("scandir");
1499
if(errno == ENOENT){
1501
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1502
" found\n", hookdir);
1505
perror_plus("scandir");
1508
struct dirent *direntry;
1400
1510
int devnull = open("/dev/null", O_RDONLY);
1401
1511
for(int i = 0; i < numhooks; i++){
1402
1512
direntry = direntries[i];
1626
error_t bring_up_interface(const char *const interface,
1629
error_t old_errno = errno;
1630
error_t ret_errno = 0;
1631
int ret, ret_setflags;
1632
struct ifreq network;
1633
unsigned int if_index = if_nametoindex(interface);
1635
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1645
if(not interface_is_up(interface)){
1646
if(not get_flags(interface, &network) and debug){
1648
fprintf_plus(stderr, "Failed to get flags for interface "
1649
"\"%s\"\n", interface);
1652
network.ifr_flags |= IFF_UP;
1654
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1657
perror_plus("socket");
1669
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1673
/* Raise priviliges */
1677
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1678
messages about the network interface to mess up the prompt */
1679
int ret_linux = klogctl(8, NULL, 5);
1680
bool restore_loglevel = true;
1681
if(ret_linux == -1){
1682
restore_loglevel = false;
1683
perror_plus("klogctl");
1685
#endif /* __linux__ */
1686
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1689
if(restore_loglevel){
1690
ret_linux = klogctl(7, NULL, 0);
1691
if(ret_linux == -1){
1692
perror_plus("klogctl");
1695
#endif /* __linux__ */
1697
/* Lower privileges */
1700
/* Close the socket */
1701
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1703
perror_plus("close");
1706
if(ret_setflags == -1){
1708
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1713
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1717
/* Sleep checking until interface is running.
1718
Check every 0.25s, up to total time of delay */
1719
for(int i=0; i < delay * 4; i++){
1720
if(interface_is_running(interface)){
1723
struct timespec sleeptime = { .tv_nsec = 250000000 };
1724
ret = nanosleep(&sleeptime, NULL);
1725
if(ret == -1 and errno != EINTR){
1726
perror_plus("nanosleep");
1734
error_t take_down_interface(const char *const interface){
1735
error_t old_errno = errno;
1736
struct ifreq network;
1737
unsigned int if_index = if_nametoindex(interface);
1739
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1743
if(interface_is_up(interface)){
1744
error_t ret_errno = 0;
1745
if(not get_flags(interface, &network) and debug){
1747
fprintf_plus(stderr, "Failed to get flags for interface "
1748
"\"%s\"\n", interface);
1751
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1753
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1756
perror_plus("socket");
1762
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1766
/* Raise priviliges */
1769
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1772
/* Lower privileges */
1775
/* Close the socket */
1776
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1778
perror_plus("close");
1781
if(ret_setflags == -1){
1783
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1788
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1526
1796
int main(int argc, char *argv[]){
1797
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1798
.priority = "SECURE256:!CTYPE-X.509:"
1799
"+CTYPE-OPENPGP", .current_server = NULL,
1800
.interfaces = NULL, .interfaces_size = 0 };
1527
1801
AvahiSServiceBrowser *sb = NULL;
1530
1804
intmax_t tmpmax;
1532
1806
int exitcode = EXIT_SUCCESS;
1533
const char *interface = "";
1534
struct ifreq network;
1536
bool take_down_interface = false;
1807
char *interfaces_to_take_down = NULL;
1808
size_t interfaces_to_take_down_size = 0;
1539
1809
char tempdir[] = "/tmp/mandosXXXXXX";
1540
1810
bool tempdir_created = false;
1541
1811
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1542
1812
const char *seckey = PATHDIR "/" SECKEY;
1543
1813
const char *pubkey = PATHDIR "/" PUBKEY;
1814
char *interfaces_hooks = NULL;
1545
1816
bool gnutls_initialized = false;
1546
1817
bool gpgme_initialized = false;
1773
2044
/* Lower privileges */
1777
perror_plus("seteuid");
2049
/* Remove invalid interface names (except "none") */
2051
char *interface = NULL;
2052
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2054
if(strcmp(interface, "none") != 0
2055
and if_nametoindex(interface) == 0){
2056
if(interface[0] != '\0'){
2057
fprintf_plus(stderr, "Not using nonexisting interface"
2058
" \"%s\"\n", interface);
2060
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
1782
2066
/* Run network hooks */
1783
if(not run_network_hooks("start", interface, delay)){
2068
if(mc.interfaces != NULL){
2069
interfaces_hooks = malloc(mc.interfaces_size);
2070
if(interfaces_hooks == NULL){
2071
perror_plus("malloc");
2074
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2075
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
1788
2084
avahi_set_log_function(empty_log);
1791
if(interface[0] == '\0'){
1792
struct dirent **direntries;
1793
/* First look for interfaces that are up */
1794
ret = scandir(sys_class_net, &direntries, up_interface,
1797
/* No up interfaces, look for any good interfaces */
1799
ret = scandir(sys_class_net, &direntries, good_interface,
1803
/* Pick the first interface returned */
1804
interface = strdup(direntries[0]->d_name);
1806
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1808
if(interface == NULL){
1809
perror_plus("malloc");
1811
exitcode = EXIT_FAILURE;
1817
fprintf_plus(stderr, "Could not find a network interface\n");
1818
exitcode = EXIT_FAILURE;
1823
2087
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1824
2088
from the signal handler */
1825
2089
/* Initialize the pseudo-RNG for Avahi */
1826
2090
srand((unsigned int) time(NULL));
1827
mc.simple_poll = avahi_simple_poll_new();
1828
if(mc.simple_poll == NULL){
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
1829
2093
fprintf_plus(stderr,
1830
2094
"Avahi: Failed to create simple poll object.\n");
1831
2095
exitcode = EX_UNAVAILABLE;
1898
/* If the interface is down, bring it up */
1899
if(strcmp(interface, "none") != 0){
1900
if_index = (AvahiIfIndex) if_nametoindex(interface);
1902
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1903
exitcode = EX_UNAVAILABLE;
1911
/* Re-raise priviliges */
1915
perror_plus("seteuid");
1919
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1920
messages about the network interface to mess up the prompt */
1921
ret = klogctl(8, NULL, 5);
1922
bool restore_loglevel = true;
1924
restore_loglevel = false;
1925
perror_plus("klogctl");
1927
#endif /* __linux__ */
1929
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1931
perror_plus("socket");
1932
exitcode = EX_OSERR;
1934
if(restore_loglevel){
1935
ret = klogctl(7, NULL, 0);
1937
perror_plus("klogctl");
1940
#endif /* __linux__ */
1941
/* Lower privileges */
1945
perror_plus("seteuid");
1949
strcpy(network.ifr_name, interface);
1950
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1952
perror_plus("ioctl SIOCGIFFLAGS");
1954
if(restore_loglevel){
1955
ret = klogctl(7, NULL, 0);
1957
perror_plus("klogctl");
1960
#endif /* __linux__ */
1961
exitcode = EX_OSERR;
1962
/* Lower privileges */
1966
perror_plus("seteuid");
1970
if((network.ifr_flags & IFF_UP) == 0){
1971
network.ifr_flags |= IFF_UP;
1972
take_down_interface = true;
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1975
take_down_interface = false;
1976
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1977
exitcode = EX_OSERR;
1979
if(restore_loglevel){
1980
ret = klogctl(7, NULL, 0);
1982
perror_plus("klogctl");
2162
/* If no interfaces were specified, make a list */
2163
if(mc.interfaces == NULL){
2164
struct dirent **direntries;
2165
/* Look for any good interfaces */
2166
ret = scandir(sys_class_net, &direntries, good_interface,
2169
/* Add all found interfaces to interfaces list */
2170
for(int i = 0; i < ret; ++i){
2171
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2172
direntries[i]->d_name);
2175
perror_plus("argz_add");
2179
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2180
direntries[i]->d_name);
2186
fprintf_plus(stderr, "Could not find a network interface\n");
2187
exitcode = EXIT_FAILURE;
2192
/* Bring up interfaces which are down, and remove any "none"s */
2194
char *interface = NULL;
2195
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2197
/* If interface name is "none", stop bringing up interfaces.
2198
Also remove all instances of "none" from the list */
2199
if(strcmp(interface, "none") == 0){
2200
argz_delete(&mc.interfaces, &mc.interfaces_size,
2203
while((interface = argz_next(mc.interfaces,
2204
mc.interfaces_size, interface))){
2205
if(strcmp(interface, "none") == 0){
2206
argz_delete(&mc.interfaces, &mc.interfaces_size,
1985
#endif /* __linux__ */
1986
/* Lower privileges */
1990
perror_plus("seteuid");
1995
/* Sleep checking until interface is running.
1996
Check every 0.25s, up to total time of delay */
1997
for(int i=0; i < delay * 4; i++){
1998
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2000
perror_plus("ioctl SIOCGIFFLAGS");
2001
} else if(network.ifr_flags & IFF_RUNNING){
2004
struct timespec sleeptime = { .tv_nsec = 250000000 };
2005
ret = nanosleep(&sleeptime, NULL);
2006
if(ret == -1 and errno != EINTR){
2007
perror_plus("nanosleep");
2010
if(not take_down_interface){
2011
/* We won't need the socket anymore */
2012
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2014
perror_plus("close");
2018
if(restore_loglevel){
2019
/* Restores kernel loglevel to default */
2020
ret = klogctl(7, NULL, 0);
2022
perror_plus("klogctl");
2025
#endif /* __linux__ */
2026
/* Lower privileges */
2028
/* Lower privileges */
2031
perror_plus("seteuid");
2213
bool interface_was_up = interface_is_up(interface);
2214
ret = bring_up_interface(interface, delay);
2215
if(not interface_was_up){
2218
perror_plus("Failed to bring up interface");
2220
ret_errno = argz_add(&interfaces_to_take_down,
2221
&interfaces_to_take_down_size,
2225
perror_plus("argz_add");
2230
if(debug and (interfaces_to_take_down == NULL)){
2231
fprintf_plus(stderr, "No interfaces were brought up\n");
2235
/* If we only got one interface, explicitly use only that one */
2236
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2238
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2241
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2039
ret = init_gnutls_global(pubkey, seckey);
2248
ret = init_gnutls_global(pubkey, seckey, &mc);
2041
2250
fprintf_plus(stderr, "init_gnutls_global failed\n");
2042
2251
exitcode = EX_UNAVAILABLE;
2241
/* Run network hooks */
2242
run_network_hooks("stop", interface, delay);
2244
2454
/* Re-raise priviliges */
2249
perror_plus("seteuid");
2252
/* Take down the network interface */
2253
if(take_down_interface and geteuid() == 0){
2254
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2256
perror_plus("ioctl SIOCGIFFLAGS");
2257
} else if(network.ifr_flags & IFF_UP){
2258
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2259
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2261
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2458
/* Run network hooks */
2459
run_network_hooks("stop", interfaces_hooks != NULL ?
2460
interfaces_hooks : "", delay);
2462
/* Take down the network interfaces which were brought up */
2464
char *interface = NULL;
2465
while((interface=argz_next(interfaces_to_take_down,
2466
interfaces_to_take_down_size,
2468
ret_errno = take_down_interface(interface);
2471
perror_plus("Failed to take down interface");
2264
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2266
perror_plus("close");
2474
if(debug and (interfaces_to_take_down == NULL)){
2475
fprintf_plus(stderr, "No interfaces needed to be taken"
2270
/* Lower privileges permanently */
2274
perror_plus("setuid");
2480
lower_privileges_permanently();
2483
free(interfaces_to_take_down);
2484
free(interfaces_hooks);
2277
2486
/* Removes the GPGME temp directory and all files inside */
2278
2487
if(tempdir_created){