161
157
const char *priority;
163
159
server *current_server;
165
size_t interfaces_size;
166
160
} mandos_context;
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
162
/* global context so signal handler can reach it*/
163
mandos_context mc = { .simple_poll = NULL, .server = NULL,
164
.dh_bits = 1024, .priority = "SECURE256"
165
":!CTYPE-X.509:+CTYPE-OPENPGP",
166
.current_server = NULL };
171
168
sig_atomic_t quit_now = 0;
172
169
int signal_received = 0;
174
171
/* Function to use when printing errors */
175
172
void perror_plus(const char *print_text){
177
173
fprintf(stderr, "Mandos plugin %s: ",
178
174
program_invocation_short_name);
180
175
perror(print_text);
183
__attribute__((format (gnu_printf, 2, 3)))
184
178
int fprintf_plus(FILE *stream, const char *format, ...){
186
180
va_start (ap, format);
188
182
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
183
program_invocation_short_name));
190
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
184
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
227
221
/* Special case of first server */
228
if(*current_server == NULL){
222
if (mc.current_server == NULL){
229
223
new_server->next = new_server;
230
224
new_server->prev = new_server;
231
*current_server = new_server;
225
mc.current_server = new_server;
232
226
/* Place the new server last in the list */
234
new_server->next = *current_server;
235
new_server->prev = (*current_server)->prev;
228
new_server->next = mc.current_server;
229
new_server->prev = mc.current_server->prev;
236
230
new_server->prev->next = new_server;
237
(*current_server)->prev = new_server;
231
mc.current_server->prev = new_server;
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
233
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
241
235
perror_plus("clock_gettime");
535
529
/* GnuTLS server initialization */
536
ret = gnutls_dh_params_init(&mc->dh_params);
530
ret = gnutls_dh_params_init(&mc.dh_params);
537
531
if(ret != GNUTLS_E_SUCCESS){
538
532
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
539
533
" initialization: %s\n",
540
534
safer_gnutls_strerror(ret));
543
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
537
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
544
538
if(ret != GNUTLS_E_SUCCESS){
545
539
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
546
540
safer_gnutls_strerror(ret));
550
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
544
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
556
gnutls_certificate_free_credentials(mc->cred);
550
gnutls_certificate_free_credentials(mc.cred);
557
551
gnutls_global_deinit();
558
gnutls_dh_params_deinit(mc->dh_params);
552
gnutls_dh_params_deinit(mc.dh_params);
562
static int init_gnutls_session(gnutls_session_t *session,
556
static int init_gnutls_session(gnutls_session_t *session){
565
558
/* GnuTLS session creation */
662
/* If the interface is specified and we have a list of interfaces */
663
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
664
/* Check if the interface is one of the interfaces we are using */
667
char *interface = NULL;
668
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
670
if(if_nametoindex(interface) == (unsigned int)if_index){
677
/* This interface does not match any in the list, so we don't
678
connect to the server */
680
char interface[IF_NAMESIZE];
681
if(if_indextoname((unsigned int)if_index, interface) == NULL){
682
perror_plus("if_indextoname");
684
fprintf_plus(stderr, "Skipping server on non-used interface"
686
if_indextoname((unsigned int)if_index,
694
ret = init_gnutls_session(&session, mc);
655
ret = init_gnutls_session(&session);
700
661
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
662
PRIu16 "\n", ip, port);
704
665
tcp_sd = socket(pf, SOCK_STREAM, 0);
769
729
if(if_indextoname((unsigned int)if_index, interface) == NULL){
770
730
perror_plus("if_indextoname");
772
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
773
"\n", ip, interface, (uintmax_t)port);
732
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
733
"\n", ip, interface, port);
776
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
777
ip, (uintmax_t)port);
736
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
779
739
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
780
740
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1071
1025
PRIdMAX ") on port %" PRIu16 "\n", name,
1072
1026
host_name, ip, (intmax_t)interface, port);
1074
int ret = start_mandos_communication(ip, (in_port_t)port,
1076
avahi_proto_to_af(proto),
1028
int ret = start_mandos_communication(ip, port, interface,
1029
avahi_proto_to_af(proto));
1079
avahi_simple_poll_quit(simple_poll);
1031
avahi_simple_poll_quit(mc.simple_poll);
1081
if(not add_server(ip, (in_port_t)port, interface,
1082
avahi_proto_to_af(proto),
1083
&((mandos_context*)mc)->current_server)){
1033
if(not add_server(ip, port, interface,
1034
avahi_proto_to_af(proto))){
1084
1035
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1085
1036
" list\n", name);
1127
1075
the callback function is called the Avahi server will free the
1128
1076
resolver for us. */
1130
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1131
interface, protocol, name, type,
1132
domain, protocol, 0,
1133
resolve_callback, mc) == NULL)
1078
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1079
name, type, domain, protocol, 0,
1080
resolve_callback, NULL) == NULL)
1134
1081
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1136
avahi_strerror(avahi_server_errno
1137
(((mandos_context*)mc)->server)));
1083
avahi_strerror(avahi_server_errno(mc.server)));
1140
1086
case AVAHI_BROWSER_REMOVE:
1260
* This function determines if a network interface is up.
1262
bool interface_is_up(const char *interface){
1264
if(not get_flags(interface, &ifr)){
1266
fprintf_plus(stderr, "Failed to get flags for interface "
1267
"\"%s\"\n", interface);
1272
return (bool)(ifr.ifr_flags & IFF_UP);
1276
* This function determines if a network interface is running
1278
bool interface_is_running(const char *interface){
1280
if(not get_flags(interface, &ifr)){
1282
fprintf_plus(stderr, "Failed to get flags for interface "
1283
"\"%s\"\n", interface);
1288
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1201
* This function determines if a directory entry in /sys/class/net
1202
* corresponds to an acceptable network device which is up.
1203
* (This function is passed to scandir(3) as a filter function.)
1205
int up_interface(const struct dirent *if_entry){
1206
if(if_entry->d_name[0] == '.'){
1211
if(not get_flags(if_entry->d_name, &ifr)){
1213
fprintf_plus(stderr, "Failed to get flags for interface "
1214
"\"%s\"\n", if_entry->d_name);
1219
/* Reject down interfaces */
1220
if(not (ifr.ifr_flags & IFF_UP)){
1222
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1228
/* Reject non-running interfaces */
1229
if(not (ifr.ifr_flags & IFF_RUNNING)){
1231
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1237
if(not good_flags(if_entry->d_name, &ifr)){
1291
1243
int notdotentries(const struct dirent *direntry){
1406
1357
if(block_time <= 0){
1407
ret = start_mandos_communication(mc->current_server->ip,
1408
mc->current_server->port,
1409
mc->current_server->if_index,
1410
mc->current_server->af, mc);
1358
ret = start_mandos_communication(mc.current_server->ip,
1359
mc.current_server->port,
1360
mc.current_server->if_index,
1361
mc.current_server->af);
1412
avahi_simple_poll_quit(s);
1363
avahi_simple_poll_quit(mc.simple_poll);
1415
1366
ret = clock_gettime(CLOCK_MONOTONIC,
1416
&mc->current_server->last_seen);
1367
&mc.current_server->last_seen);
1418
1369
perror_plus("clock_gettime");
1421
mc->current_server = mc->current_server->next;
1372
mc.current_server = mc.current_server->next;
1422
1373
block_time = 0; /* Call avahi to find new Mandos
1423
1374
servers, but don't block */
1621
error_t bring_up_interface(const char *const interface,
1624
error_t old_errno = errno;
1625
error_t ret_errno = 0;
1626
int ret, ret_setflags;
1627
struct ifreq network;
1628
unsigned int if_index = if_nametoindex(interface);
1630
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1640
if(not interface_is_up(interface)){
1641
if(not get_flags(interface, &network) and debug){
1643
fprintf_plus(stderr, "Failed to get flags for interface "
1644
"\"%s\"\n", interface);
1647
network.ifr_flags |= IFF_UP;
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1652
perror_plus("socket");
1664
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1668
/* Raise priviliges */
1672
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1673
messages about the network interface to mess up the prompt */
1674
int ret_linux = klogctl(8, NULL, 5);
1675
bool restore_loglevel = true;
1676
if(ret_linux == -1){
1677
restore_loglevel = false;
1678
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1684
if(restore_loglevel){
1685
ret_linux = klogctl(7, NULL, 0);
1686
if(ret_linux == -1){
1687
perror_plus("klogctl");
1690
#endif /* __linux__ */
1692
/* Lower privileges */
1695
/* Close the socket */
1696
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1698
perror_plus("close");
1701
if(ret_setflags == -1){
1703
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1708
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1712
/* Sleep checking until interface is running.
1713
Check every 0.25s, up to total time of delay */
1714
for(int i=0; i < delay * 4; i++){
1715
if(interface_is_running(interface)){
1718
struct timespec sleeptime = { .tv_nsec = 250000000 };
1719
ret = nanosleep(&sleeptime, NULL);
1720
if(ret == -1 and errno != EINTR){
1721
perror_plus("nanosleep");
1729
error_t take_down_interface(const char *const interface){
1731
error_t old_errno = errno;
1732
error_t ret_errno = 0;
1733
int ret, ret_setflags;
1734
struct ifreq network;
1735
unsigned int if_index = if_nametoindex(interface);
1737
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1741
if(interface_is_up(interface)){
1742
if(not get_flags(interface, &network) and debug){
1744
fprintf_plus(stderr, "Failed to get flags for interface "
1745
"\"%s\"\n", interface);
1748
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1750
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1753
perror_plus("socket");
1759
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1763
/* Raise priviliges */
1766
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1769
/* Lower privileges */
1772
/* Close the socket */
1773
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1775
perror_plus("close");
1778
if(ret_setflags == -1){
1780
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1785
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1793
1514
int main(int argc, char *argv[]){
1794
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1795
.priority = "SECURE256:!CTYPE-X.509:"
1796
"+CTYPE-OPENPGP", .current_server = NULL,
1797
.interfaces = NULL, .interfaces_size = 0 };
1798
1515
AvahiSServiceBrowser *sb = NULL;
1801
1518
intmax_t tmpmax;
1803
1520
int exitcode = EXIT_SUCCESS;
1804
char *interfaces_to_take_down = NULL;
1805
size_t interfaces_to_take_down_size = 0;
1521
const char *interface = "";
1522
struct ifreq network;
1524
bool take_down_interface = false;
1806
1527
char tempdir[] = "/tmp/mandosXXXXXX";
1807
1528
bool tempdir_created = false;
1808
1529
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1809
1530
const char *seckey = PATHDIR "/" SECKEY;
1810
1531
const char *pubkey = PATHDIR "/" PUBKEY;
1811
char *interfaces_hooks = NULL;
1812
size_t interfaces_hooks_size = 0;
1814
1533
bool gnutls_initialized = false;
1815
1534
bool gpgme_initialized = false;
2042
1761
/* Lower privileges */
2047
/* Remove invalid interface names (except "none") */
2049
char *interface = NULL;
2050
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2052
if(strcmp(interface, "none") != 0
2053
and if_nametoindex(interface) == 0){
2054
if(interface[0] != '\0'){
2055
fprintf_plus(stderr, "Not using nonexisting interface"
2056
" \"%s\"\n", interface);
2058
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
1765
perror_plus("seteuid");
2064
1770
/* Run network hooks */
2066
if(mc.interfaces != NULL){
2067
interfaces_hooks = malloc(mc.interfaces_size);
2068
if(interfaces_hooks == NULL){
2069
perror_plus("malloc");
2072
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2073
interfaces_hooks_size = mc.interfaces_size;
2074
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
1771
if(not run_network_hooks("start", interface, delay)){
2084
1776
avahi_set_log_function(empty_log);
1779
if(interface[0] == '\0'){
1780
struct dirent **direntries;
1781
/* First look for interfaces that are up */
1782
ret = scandir(sys_class_net, &direntries, up_interface,
1785
/* No up interfaces, look for any good interfaces */
1787
ret = scandir(sys_class_net, &direntries, good_interface,
1791
/* Pick the first interface returned */
1792
interface = strdup(direntries[0]->d_name);
1794
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1796
if(interface == NULL){
1797
perror_plus("malloc");
1799
exitcode = EXIT_FAILURE;
1805
fprintf_plus(stderr, "Could not find a network interface\n");
1806
exitcode = EXIT_FAILURE;
2087
1811
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2088
1812
from the signal handler */
2089
1813
/* Initialize the pseudo-RNG for Avahi */
2090
1814
srand((unsigned int) time(NULL));
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
1815
mc.simple_poll = avahi_simple_poll_new();
1816
if(mc.simple_poll == NULL){
2093
1817
fprintf_plus(stderr,
2094
1818
"Avahi: Failed to create simple poll object.\n");
2095
1819
exitcode = EX_UNAVAILABLE;
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);
2174
perror_plus("argz_add");
2178
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2179
direntries[i]->d_name);
2185
fprintf_plus(stderr, "Could not find a network interface\n");
2186
exitcode = EXIT_FAILURE;
2191
/* Bring up interfaces which are down, and remove any "none"s */
2193
char *interface = NULL;
2194
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2196
/* If interface name is "none", stop bringing up interfaces.
2197
Also remove all instances of "none" from the list */
2198
if(strcmp(interface, "none") == 0){
2199
argz_delete(&mc.interfaces, &mc.interfaces_size,
2202
while((interface = argz_next(mc.interfaces,
2203
mc.interfaces_size, interface))){
2204
if(strcmp(interface, "none") == 0){
2205
argz_delete(&mc.interfaces, &mc.interfaces_size,
1886
/* If the interface is down, bring it up */
1887
if(strcmp(interface, "none") != 0){
1888
if_index = (AvahiIfIndex) if_nametoindex(interface);
1890
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1891
exitcode = EX_UNAVAILABLE;
1899
/* Re-raise priviliges */
1903
perror_plus("seteuid");
1907
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1908
messages about the network interface to mess up the prompt */
1909
ret = klogctl(8, NULL, 5);
1910
bool restore_loglevel = true;
1912
restore_loglevel = false;
1913
perror_plus("klogctl");
1915
#endif /* __linux__ */
1917
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1919
perror_plus("socket");
1920
exitcode = EX_OSERR;
1922
if(restore_loglevel){
1923
ret = klogctl(7, NULL, 0);
1925
perror_plus("klogctl");
1928
#endif /* __linux__ */
1929
/* Lower privileges */
1933
perror_plus("seteuid");
1937
strcpy(network.ifr_name, interface);
1938
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1940
perror_plus("ioctl SIOCGIFFLAGS");
1942
if(restore_loglevel){
1943
ret = klogctl(7, NULL, 0);
1945
perror_plus("klogctl");
1948
#endif /* __linux__ */
1949
exitcode = EX_OSERR;
1950
/* Lower privileges */
1954
perror_plus("seteuid");
1958
if((network.ifr_flags & IFF_UP) == 0){
1959
network.ifr_flags |= IFF_UP;
1960
take_down_interface = true;
1961
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1963
take_down_interface = false;
1964
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1965
exitcode = EX_OSERR;
1967
if(restore_loglevel){
1968
ret = klogctl(7, NULL, 0);
1970
perror_plus("klogctl");
1973
#endif /* __linux__ */
1974
/* Lower privileges */
1978
perror_plus("seteuid");
1983
/* Sleep checking until interface is running.
1984
Check every 0.25s, up to total time of delay */
1985
for(int i=0; i < delay * 4; i++){
1986
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1988
perror_plus("ioctl SIOCGIFFLAGS");
1989
} else if(network.ifr_flags & IFF_RUNNING){
2212
bool interface_was_up = interface_is_up(interface);
2213
ret = bring_up_interface(interface, delay);
2214
if(not interface_was_up){
2217
perror_plus("Failed to bring up interface");
2219
ret_errno = argz_add(&interfaces_to_take_down,
2220
&interfaces_to_take_down_size,
2225
if(debug and (interfaces_to_take_down == NULL)){
2226
fprintf_plus(stderr, "No interfaces were brought up\n");
2230
/* If we only got one interface, explicitly use only that one */
2231
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2233
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2236
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1992
struct timespec sleeptime = { .tv_nsec = 250000000 };
1993
ret = nanosleep(&sleeptime, NULL);
1994
if(ret == -1 and errno != EINTR){
1995
perror_plus("nanosleep");
1998
if(not take_down_interface){
1999
/* We won't need the socket anymore */
2000
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2002
perror_plus("close");
2006
if(restore_loglevel){
2007
/* Restores kernel loglevel to default */
2008
ret = klogctl(7, NULL, 0);
2010
perror_plus("klogctl");
2013
#endif /* __linux__ */
2014
/* Lower privileges */
2016
/* Lower privileges */
2019
perror_plus("seteuid");
2243
ret = init_gnutls_global(pubkey, seckey, &mc);
2027
ret = init_gnutls_global(pubkey, seckey);
2245
2029
fprintf_plus(stderr, "init_gnutls_global failed\n");
2246
2030
exitcode = EX_UNAVAILABLE;
2229
/* Run network hooks */
2230
run_network_hooks("stop", interface, delay);
2449
2232
/* Re-raise priviliges */
2453
/* Run network hooks */
2454
run_network_hooks("stop", interfaces_hooks != NULL ?
2455
interfaces_hooks : "", delay);
2457
/* Take down the network interfaces which were brought up */
2459
char *interface = NULL;
2460
while((interface=argz_next(interfaces_to_take_down,
2461
interfaces_to_take_down_size,
2463
ret_errno = take_down_interface(interface);
2466
perror_plus("Failed to take down interface");
2237
perror_plus("seteuid");
2240
/* Take down the network interface */
2241
if(take_down_interface and geteuid() == 0){
2242
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2244
perror_plus("ioctl SIOCGIFFLAGS");
2245
} else if(network.ifr_flags & IFF_UP){
2246
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2247
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2249
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2469
if(debug and (interfaces_to_take_down == NULL)){
2470
fprintf_plus(stderr, "No interfaces needed to be taken"
2252
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2254
perror_plus("close");
2475
lower_privileges_permanently();
2478
free(interfaces_to_take_down);
2479
free(interfaces_hooks);
2258
/* Lower privileges permanently */
2262
perror_plus("setuid");
2481
2265
/* Removes the GPGME temp directory and all files inside */
2482
2266
if(tempdir_created){