1374
1443
ret = avahi_simple_poll_iterate(s, (int)block_time);
1377
if (ret > 0 or errno != EINTR){
1446
if(ret > 0 or errno != EINTR){
1378
1447
return (ret != 1) ? ret : 0;
1384
bool run_network_hooks(const char *mode, const char *interface,
1453
/* Set effective uid to 0, return errno */
1454
__attribute__((warn_unused_result))
1455
error_t raise_privileges(void){
1456
error_t old_errno = errno;
1457
error_t ret_errno = 0;
1458
if(seteuid(0) == -1){
1460
perror_plus("seteuid");
1466
/* Set effective and real user ID to 0. Return errno. */
1467
__attribute__((warn_unused_result))
1468
error_t raise_privileges_permanently(void){
1469
error_t old_errno = errno;
1470
error_t ret_errno = raise_privileges();
1475
if(setuid(0) == -1){
1477
perror_plus("seteuid");
1483
/* Set effective user ID to unprivileged saved user ID */
1484
__attribute__((warn_unused_result))
1485
error_t lower_privileges(void){
1486
error_t old_errno = errno;
1487
error_t ret_errno = 0;
1488
if(seteuid(uid) == -1){
1490
perror_plus("seteuid");
1496
/* Lower privileges permanently */
1497
__attribute__((warn_unused_result))
1498
error_t lower_privileges_permanently(void){
1499
error_t old_errno = errno;
1500
error_t ret_errno = 0;
1501
if(setuid(uid) == -1){
1503
perror_plus("setuid");
1511
* Based on the example in the GNU LibC manual chapter 13.13 "File
1512
* Descriptor Flags".
1513
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
1515
__attribute__((warn_unused_result))
1516
static int set_cloexec_flag(int fd){
1517
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
1518
/* If reading the flags failed, return error indication now. */
1522
/* Store modified flag word in the descriptor. */
1523
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
1526
#endif /* not O_CLOEXEC */
1528
__attribute__((nonnull))
1529
void run_network_hooks(const char *mode, const char *interface,
1385
1530
const float delay){
1386
1531
struct dirent **direntries;
1387
struct dirent *direntry;
1389
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1532
if(hookdir_fd == -1){
1533
hookdir_fd = open(hookdir, O_RDONLY |
1536
#else /* not O_CLOEXEC */
1538
#endif /* not O_CLOEXEC */
1540
if(hookdir_fd == -1){
1541
if(errno == ENOENT){
1543
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1544
" found\n", hookdir);
1547
perror_plus("open");
1552
if(set_cloexec_flag(hookdir_fd) < 0){
1553
perror_plus("set_cloexec_flag");
1554
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1555
perror_plus("close");
1561
#endif /* not O_CLOEXEC */
1564
#if __GLIBC_PREREQ(2, 15)
1565
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1566
runnable_hook, alphasort);
1567
#else /* not __GLIBC_PREREQ(2, 15) */
1568
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1570
#endif /* not __GLIBC_PREREQ(2, 15) */
1571
#else /* not __GLIBC__ */
1572
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1574
#endif /* not __GLIBC__ */
1391
1575
if(numhooks == -1){
1392
1576
perror_plus("scandir");
1394
int devnull = open("/dev/null", O_RDONLY);
1395
for(int i = 0; i < numhooks; i++){
1396
direntry = direntries[i];
1397
char *fullname = NULL;
1398
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1579
struct dirent *direntry;
1581
int devnull = open("/dev/null", O_RDONLY);
1582
for(int i = 0; i < numhooks; i++){
1583
direntry = direntries[i];
1585
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1588
pid_t hook_pid = fork();
1591
/* Raise privileges */
1592
if(raise_privileges_permanently() != 0){
1593
perror_plus("Failed to raise privileges");
1600
perror_plus("setgid");
1603
/* Reset supplementary groups */
1605
ret = setgroups(0, NULL);
1607
perror_plus("setgroups");
1610
ret = dup2(devnull, STDIN_FILENO);
1612
perror_plus("dup2(devnull, STDIN_FILENO)");
1615
ret = close(devnull);
1617
perror_plus("close");
1620
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1622
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1625
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1627
perror_plus("setenv");
1630
ret = setenv("DEVICE", interface, 1);
1632
perror_plus("setenv");
1635
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1637
perror_plus("setenv");
1640
ret = setenv("MODE", mode, 1);
1642
perror_plus("setenv");
1646
ret = asprintf(&delaystring, "%f", (double)delay);
1400
1648
perror_plus("asprintf");
1404
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1407
pid_t hook_pid = fork();
1410
/* Raise privileges */
1414
perror_plus("seteuid");
1416
/* Raise privileges even more */
1420
perror_plus("setuid");
1426
perror_plus("setgid");
1428
/* Reset supplementary groups */
1430
ret = setgroups(0, NULL);
1432
perror_plus("setgroups");
1434
dup2(devnull, STDIN_FILENO);
1436
dup2(STDERR_FILENO, STDOUT_FILENO);
1437
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1439
perror_plus("setenv");
1442
ret = setenv("DEVICE", interface, 1);
1444
perror_plus("setenv");
1447
ret = setenv("VERBOSE", debug ? "1" : "0", 1);
1449
perror_plus("setenv");
1452
ret = setenv("MODE", mode, 1);
1454
perror_plus("setenv");
1458
ret = asprintf(&delaystring, "%f", delay);
1460
perror_plus("asprintf");
1463
ret = setenv("DELAY", delaystring, 1);
1466
perror_plus("setenv");
1651
ret = setenv("DELAY", delaystring, 1);
1469
1653
free(delaystring);
1470
ret = execl(fullname, direntry->d_name, mode, NULL);
1471
perror_plus("execl");
1474
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1475
perror_plus("waitpid");
1479
if(WIFEXITED(status)){
1480
if(WEXITSTATUS(status) != 0){
1481
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1482
" with status %d\n", direntry->d_name,
1483
WEXITSTATUS(status));
1487
} else if(WIFSIGNALED(status)){
1488
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1489
" signal %d\n", direntry->d_name,
1494
fprintf_plus(stderr, "Warning: network hook \"%s\""
1495
" crashed\n", direntry->d_name);
1502
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1654
perror_plus("setenv");
1658
if(connect_to != NULL){
1659
ret = setenv("CONNECT", connect_to, 1);
1661
perror_plus("setenv");
1665
if(fexecve(hookdir_fd, (char *const [])
1666
{ direntry->d_name, NULL }, environ) == -1){
1667
perror_plus("fexecve");
1668
_exit(EXIT_FAILURE);
1672
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1673
perror_plus("waitpid");
1676
if(WIFEXITED(status)){
1677
if(WEXITSTATUS(status) != 0){
1678
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1679
" with status %d\n", direntry->d_name,
1680
WEXITSTATUS(status));
1683
} else if(WIFSIGNALED(status)){
1684
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1685
" signal %d\n", direntry->d_name,
1689
fprintf_plus(stderr, "Warning: network hook \"%s\""
1690
" crashed\n", direntry->d_name);
1695
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1699
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1700
perror_plus("close");
1707
__attribute__((nonnull, warn_unused_result))
1708
error_t bring_up_interface(const char *const interface,
1710
error_t old_errno = errno;
1712
struct ifreq network;
1713
unsigned int if_index = if_nametoindex(interface);
1715
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1725
if(not interface_is_up(interface)){
1726
error_t ret_errno = 0, ioctl_errno = 0;
1727
if(not get_flags(interface, &network)){
1729
fprintf_plus(stderr, "Failed to get flags for interface "
1730
"\"%s\"\n", interface);
1734
network.ifr_flags |= IFF_UP; /* set flag */
1736
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1739
perror_plus("socket");
1745
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1747
perror_plus("close");
1754
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1758
/* Raise privileges */
1759
ret_errno = raise_privileges();
1761
perror_plus("Failed to raise privileges");
1766
bool restore_loglevel = false;
1768
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1769
messages about the network interface to mess up the prompt */
1770
ret_linux = klogctl(8, NULL, 5);
1771
if(ret_linux == -1){
1772
perror_plus("klogctl");
1774
restore_loglevel = true;
1777
#endif /* __linux__ */
1778
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1779
ioctl_errno = errno;
1781
if(restore_loglevel){
1782
ret_linux = klogctl(7, NULL, 0);
1783
if(ret_linux == -1){
1784
perror_plus("klogctl");
1787
#endif /* __linux__ */
1789
/* If raise_privileges() succeeded above */
1791
/* Lower privileges */
1792
ret_errno = lower_privileges();
1795
perror_plus("Failed to lower privileges");
1799
/* Close the socket */
1800
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1802
perror_plus("close");
1805
if(ret_setflags == -1){
1806
errno = ioctl_errno;
1807
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1812
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1816
/* Sleep checking until interface is running.
1817
Check every 0.25s, up to total time of delay */
1818
for(int i=0; i < delay * 4; i++){
1819
if(interface_is_running(interface)){
1822
struct timespec sleeptime = { .tv_nsec = 250000000 };
1823
ret = nanosleep(&sleeptime, NULL);
1824
if(ret == -1 and errno != EINTR){
1825
perror_plus("nanosleep");
1833
__attribute__((nonnull, warn_unused_result))
1834
error_t take_down_interface(const char *const interface){
1835
error_t old_errno = errno;
1836
struct ifreq network;
1837
unsigned int if_index = if_nametoindex(interface);
1839
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1843
if(interface_is_up(interface)){
1844
error_t ret_errno = 0, ioctl_errno = 0;
1845
if(not get_flags(interface, &network) and debug){
1847
fprintf_plus(stderr, "Failed to get flags for interface "
1848
"\"%s\"\n", interface);
1852
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1854
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1857
perror_plus("socket");
1863
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1867
/* Raise privileges */
1868
ret_errno = raise_privileges();
1870
perror_plus("Failed to raise privileges");
1873
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1874
ioctl_errno = errno;
1876
/* If raise_privileges() succeeded above */
1878
/* Lower privileges */
1879
ret_errno = lower_privileges();
1882
perror_plus("Failed to lower privileges");
1886
/* Close the socket */
1887
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1889
perror_plus("close");
1892
if(ret_setflags == -1){
1893
errno = ioctl_errno;
1894
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1899
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1511
1907
int main(int argc, char *argv[]){
1908
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1909
.priority = "SECURE256:!CTYPE-X.509:"
1910
"+CTYPE-OPENPGP", .current_server = NULL,
1911
.interfaces = NULL, .interfaces_size = 0 };
1512
1912
AvahiSServiceBrowser *sb = NULL;
1515
1915
intmax_t tmpmax;
1517
1917
int exitcode = EXIT_SUCCESS;
1518
const char *interface = "";
1519
struct ifreq network;
1521
bool take_down_interface = false;
1524
char tempdir[] = "/tmp/mandosXXXXXX";
1525
bool tempdir_created = false;
1918
char *interfaces_to_take_down = NULL;
1919
size_t interfaces_to_take_down_size = 0;
1920
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1921
char old_tempdir[] = "/tmp/mandosXXXXXX";
1922
char *tempdir = NULL;
1526
1923
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1527
1924
const char *seckey = PATHDIR "/" SECKEY;
1528
1925
const char *pubkey = PATHDIR "/" PUBKEY;
1926
char *interfaces_hooks = NULL;
1530
1928
bool gnutls_initialized = false;
1531
1929
bool gpgme_initialized = false;
1760
2160
/* Lower privileges */
1764
perror_plus("seteuid");
2161
ret_errno = lower_privileges();
2164
perror_plus("Failed to lower privileges");
2169
/* Remove invalid interface names (except "none") */
2171
char *interface = NULL;
2172
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2174
if(strcmp(interface, "none") != 0
2175
and if_nametoindex(interface) == 0){
2176
if(interface[0] != '\0'){
2177
fprintf_plus(stderr, "Not using nonexisting interface"
2178
" \"%s\"\n", interface);
2180
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
1769
2186
/* Run network hooks */
1770
if(not run_network_hooks("start", interface, delay)){
2188
if(mc.interfaces != NULL){
2189
interfaces_hooks = malloc(mc.interfaces_size);
2190
if(interfaces_hooks == NULL){
2191
perror_plus("malloc");
2194
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2195
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2197
run_network_hooks("start", interfaces_hooks != NULL ?
2198
interfaces_hooks : "", delay);
1775
2202
avahi_set_log_function(empty_log);
1778
if(interface[0] == '\0'){
1779
struct dirent **direntries;
1780
/* First look for interfaces that are up */
1781
ret = scandir(sys_class_net, &direntries, up_interface,
1784
/* No up interfaces, look for any good interfaces */
1786
ret = scandir(sys_class_net, &direntries, good_interface,
1790
/* Pick the first interface returned */
1791
interface = strdup(direntries[0]->d_name);
1793
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1795
if(interface == NULL){
1796
perror_plus("malloc");
1798
exitcode = EXIT_FAILURE;
1804
fprintf_plus(stderr, "Could not find a network interface\n");
1805
exitcode = EXIT_FAILURE;
1810
2205
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1811
2206
from the signal handler */
1812
2207
/* Initialize the pseudo-RNG for Avahi */
1813
2208
srand((unsigned int) time(NULL));
1814
mc.simple_poll = avahi_simple_poll_new();
1815
if(mc.simple_poll == NULL){
2209
simple_poll = avahi_simple_poll_new();
2210
if(simple_poll == NULL){
1816
2211
fprintf_plus(stderr,
1817
2212
"Avahi: Failed to create simple poll object.\n");
1818
2213
exitcode = EX_UNAVAILABLE;
1885
/* If the interface is down, bring it up */
1886
if(strcmp(interface, "none") != 0){
1887
if_index = (AvahiIfIndex) if_nametoindex(interface);
1889
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1890
exitcode = EX_UNAVAILABLE;
1898
/* Re-raise priviliges */
1902
perror_plus("seteuid");
1906
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1907
messages about the network interface to mess up the prompt */
1908
ret = klogctl(8, NULL, 5);
1909
bool restore_loglevel = true;
1911
restore_loglevel = false;
1912
perror_plus("klogctl");
1914
#endif /* __linux__ */
1916
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1918
perror_plus("socket");
1919
exitcode = EX_OSERR;
1921
if(restore_loglevel){
1922
ret = klogctl(7, NULL, 0);
1924
perror_plus("klogctl");
1927
#endif /* __linux__ */
1928
/* Lower privileges */
1932
perror_plus("seteuid");
1936
strcpy(network.ifr_name, interface);
1937
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1939
perror_plus("ioctl SIOCGIFFLAGS");
1941
if(restore_loglevel){
1942
ret = klogctl(7, NULL, 0);
1944
perror_plus("klogctl");
1947
#endif /* __linux__ */
1948
exitcode = EX_OSERR;
1949
/* Lower privileges */
1953
perror_plus("seteuid");
1957
if((network.ifr_flags & IFF_UP) == 0){
1958
network.ifr_flags |= IFF_UP;
1959
take_down_interface = true;
1960
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1962
take_down_interface = false;
1963
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1964
exitcode = EX_OSERR;
1966
if(restore_loglevel){
1967
ret = klogctl(7, NULL, 0);
1969
perror_plus("klogctl");
2280
/* If no interfaces were specified, make a list */
2281
if(mc.interfaces == NULL){
2282
struct dirent **direntries;
2283
/* Look for any good interfaces */
2284
ret = scandir(sys_class_net, &direntries, good_interface,
2287
/* Add all found interfaces to interfaces list */
2288
for(int i = 0; i < ret; ++i){
2289
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2290
direntries[i]->d_name);
2293
perror_plus("argz_add");
2297
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2298
direntries[i]->d_name);
2304
fprintf_plus(stderr, "Could not find a network interface\n");
2305
exitcode = EXIT_FAILURE;
2310
/* Bring up interfaces which are down, and remove any "none"s */
2312
char *interface = NULL;
2313
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2315
/* If interface name is "none", stop bringing up interfaces.
2316
Also remove all instances of "none" from the list */
2317
if(strcmp(interface, "none") == 0){
2318
argz_delete(&mc.interfaces, &mc.interfaces_size,
2321
while((interface = argz_next(mc.interfaces,
2322
mc.interfaces_size, interface))){
2323
if(strcmp(interface, "none") == 0){
2324
argz_delete(&mc.interfaces, &mc.interfaces_size,
1972
#endif /* __linux__ */
1973
/* Lower privileges */
1977
perror_plus("seteuid");
1982
/* Sleep checking until interface is running.
1983
Check every 0.25s, up to total time of delay */
1984
for(int i=0; i < delay * 4; i++){
1985
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1987
perror_plus("ioctl SIOCGIFFLAGS");
1988
} else if(network.ifr_flags & IFF_RUNNING){
1991
struct timespec sleeptime = { .tv_nsec = 250000000 };
1992
ret = nanosleep(&sleeptime, NULL);
1993
if(ret == -1 and errno != EINTR){
1994
perror_plus("nanosleep");
1997
if(not take_down_interface){
1998
/* We won't need the socket anymore */
1999
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2001
perror_plus("close");
2005
if(restore_loglevel){
2006
/* Restores kernel loglevel to default */
2007
ret = klogctl(7, NULL, 0);
2009
perror_plus("klogctl");
2012
#endif /* __linux__ */
2013
/* Lower privileges */
2015
/* Lower privileges */
2018
perror_plus("seteuid");
2331
bool interface_was_up = interface_is_up(interface);
2332
errno = bring_up_interface(interface, delay);
2333
if(not interface_was_up){
2335
perror_plus("Failed to bring up interface");
2337
errno = argz_add(&interfaces_to_take_down,
2338
&interfaces_to_take_down_size,
2341
perror_plus("argz_add");
2346
if(debug and (interfaces_to_take_down == NULL)){
2347
fprintf_plus(stderr, "No interfaces were brought up\n");
2351
/* If we only got one interface, explicitly use only that one */
2352
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2354
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2357
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2026
ret = init_gnutls_global(pubkey, seckey);
2364
ret = init_gnutls_global(pubkey, seckey, &mc);
2028
2366
fprintf_plus(stderr, "init_gnutls_global failed\n");
2029
2367
exitcode = EX_UNAVAILABLE;