62
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
66
67
#include <time.h> /* nanosleep(), time(), sleep() */
67
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
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69
SIOCSIFFLAGS, if_indextoname(),
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74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
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75
getuid(), getgid(), seteuid(),
75
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setgid(), pause() */
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
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78
#include <iso646.h> /* not, or, and */
78
79
#include <argp.h> /* struct argp_option, error_t, struct
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80
argp_state, struct argp,
139
151
gnutls_dh_params_t dh_params;
140
152
const char *priority;
154
server *current_server;
142
155
} mandos_context;
144
157
/* global context so signal handler can reach it*/
145
158
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
159
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
160
":!CTYPE-X.509:+CTYPE-OPENPGP",
161
.current_server = NULL };
149
163
sig_atomic_t quit_now = 0;
150
164
int signal_received = 0;
166
/* Function to use when printing errors */
167
void perror_plus(const char *print_text){
168
fprintf(stderr, "Mandos plugin %s: ",
169
program_invocation_short_name);
153
174
* Make additional room in "buffer" for at least BUFFER_SIZE more
154
175
* bytes. "buffer_capacity" is how much is currently allocated,
166
187
return buffer_capacity;
190
int add_server(const char *ip, uint16_t port,
191
AvahiIfIndex if_index,
194
server *new_server = malloc(sizeof(server));
195
if(new_server == NULL){
196
perror_plus("malloc");
199
*new_server = (server){ .ip = strdup(ip),
201
.if_index = if_index,
203
if(new_server->ip == NULL){
204
perror_plus("strdup");
207
/* unique case of first server */
208
if (mc.current_server == NULL){
209
new_server->next = new_server;
210
new_server->prev = new_server;
211
mc.current_server = new_server;
212
/* Placing the new server last in the list */
214
new_server->next = mc.current_server;
215
new_server->prev = mc.current_server->prev;
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new_server->prev->next = new_server;
217
mc.current_server->prev = new_server;
219
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
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perror_plus("clock_gettime");
170
228
* Initialize GPGME.
425
483
/* OpenPGP credentials */
426
gnutls_certificate_allocate_credentials(&mc.cred);
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ret = gnutls_certificate_allocate_credentials(&mc.cred);
427
485
if(ret != GNUTLS_E_SUCCESS){
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
486
fprintf(stderr, "GnuTLS memory error: %s\n",
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safer_gnutls_strerror(ret));
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488
gnutls_global_deinit();
651
706
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
652
707
char interface[IF_NAMESIZE];
653
708
if(if_indextoname((unsigned int)if_index, interface) == NULL){
654
perror("if_indextoname");
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perror_plus("if_indextoname");
656
711
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
712
ip, interface, port);
1032
1092
int good_interface(const struct dirent *if_entry){
1034
1094
char *flagname = NULL;
1095
if(if_entry->d_name[0] == '.'){
1035
1098
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
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1099
if_entry->d_name);
1041
if(if_entry->d_name[0] == '.'){
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perror_plus("asprintf");
1044
1104
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1045
1105
if(flags_fd == -1){
1106
perror_plus("open");
1049
1111
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1050
1112
/* read line from flags_fd */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1113
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
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char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1053
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flagstring[(size_t)to_read] = '\0';
1054
1116
if(flagstring == NULL){
1117
perror_plus("malloc");
1056
1118
close(flags_fd);
1192
int notdotentries(const struct dirent *direntry){
1193
/* Skip "." and ".." */
1194
if(direntry->d_name[0] == '.'
1195
and (direntry->d_name[1] == '\0'
1196
or (direntry->d_name[1] == '.'
1197
and direntry->d_name[2] == '\0'))){
1203
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1205
struct timespec now;
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struct timespec waited_time;
1207
intmax_t block_time;
1210
if(mc.current_server == NULL){
1213
"Wait until first server is found. No timeout!\n");
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ret = avahi_simple_poll_iterate(s, -1);
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fprintf(stderr, "Check current_server if we should run it,"
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/* the current time */
1222
ret = clock_gettime(CLOCK_MONOTONIC, &now);
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perror_plus("clock_gettime");
1227
/* Calculating in ms how long time between now and server
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who we visted longest time ago. Now - last seen. */
1229
waited_time.tv_sec = (now.tv_sec
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- mc.current_server->last_seen.tv_sec);
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waited_time.tv_nsec = (now.tv_nsec
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- mc.current_server->last_seen.tv_nsec);
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/* total time is 10s/10,000ms.
1234
Converting to s from ms by dividing by 1,000,
1235
and ns to ms by dividing by 1,000,000. */
1236
block_time = ((retry_interval
1237
- ((intmax_t)waited_time.tv_sec * 1000))
1238
- ((intmax_t)waited_time.tv_nsec / 1000000));
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fprintf(stderr, "Blocking for %ld ms\n", block_time);
1244
if(block_time <= 0){
1245
ret = start_mandos_communication(mc.current_server->ip,
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mc.current_server->port,
1247
mc.current_server->if_index,
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mc.current_server->af);
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avahi_simple_poll_quit(mc.simple_poll);
1253
ret = clock_gettime(CLOCK_MONOTONIC,
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&mc.current_server->last_seen);
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perror_plus("clock_gettime");
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mc.current_server = mc.current_server->next;
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block_time = 0; /* Call avahi to find new Mandos
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servers, but don't block */
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ret = avahi_simple_poll_iterate(s, (int)block_time);
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if (ret > 0 or errno != EINTR) {
1268
return (ret != 1) ? ret : 0;
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int main(int argc, char *argv[]){
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AvahiSServiceBrowser *sb = NULL;
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bool gnutls_initialized = false;
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bool gpgme_initialized = false;
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float delay = 2.5f;
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double retry_interval = 10; /* 10s between trying a server and
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retrying the same server again */
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struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
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struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
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if(errno != 0 or tmp == arg or *tmp != '\0'){
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argp_error(state, "Bad delay");
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case 132: /* --retry */
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retry_interval = strtod(arg, &tmp);
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if(errno != 0 or tmp == arg or *tmp != '\0'
1414
or (retry_interval * 1000) > INT_MAX){
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argp_error(state, "Bad retry interval");
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* These reproduce what we would get without ARGP_NO_HELP
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/* Work around Debian bug #633582:
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<http://bugs.debian.org/633582> */
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/* Re-raise priviliges */
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perror_plus("seteuid");
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int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);
1472
if(seckey_fd == -1){
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perror_plus("open");
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ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
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perror_plus("fstat");
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if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
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ret = fchown(seckey_fd, uid, gid);
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perror_plus("fchown");
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TEMP_FAILURE_RETRY(close(seckey_fd));
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int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);
1490
if(pubkey_fd == -1){
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perror_plus("open");
1493
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
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perror_plus("fstat");
1497
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1498
ret = fchown(pubkey_fd, uid, gid);
1500
perror_plus("fchown");
1504
TEMP_FAILURE_RETRY(close(pubkey_fd));
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/* Lower privileges */
1511
perror_plus("seteuid");
1295
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avahi_set_log_function(empty_log);
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sigemptyset(&sigterm_action.sa_mask);
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ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
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perror("sigaddset");
1558
perror_plus("sigaddset");
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exitcode = EX_OSERR;
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ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1343
perror("sigaddset");
1564
perror_plus("sigaddset");
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1565
exitcode = EX_OSERR;
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1568
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1349
perror("sigaddset");
1570
perror_plus("sigaddset");
1350
1571
exitcode = EX_OSERR;
1357
1578
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1359
perror("sigaction");
1580
perror_plus("sigaction");
1360
1581
return EX_OSERR;
1362
1583
if(old_sigterm_action.sa_handler != SIG_IGN){
1363
1584
ret = sigaction(SIGINT, &sigterm_action, NULL);
1365
perror("sigaction");
1586
perror_plus("sigaction");
1366
1587
exitcode = EX_OSERR;
1370
1591
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1372
perror("sigaction");
1593
perror_plus("sigaction");
1373
1594
return EX_OSERR;
1375
1596
if(old_sigterm_action.sa_handler != SIG_IGN){
1376
1597
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1378
perror("sigaction");
1599
perror_plus("sigaction");
1379
1600
exitcode = EX_OSERR;
1383
1604
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1385
perror("sigaction");
1606
perror_plus("sigaction");
1386
1607
return EX_OSERR;
1388
1609
if(old_sigterm_action.sa_handler != SIG_IGN){
1389
1610
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1391
perror("sigaction");
1612
perror_plus("sigaction");
1392
1613
exitcode = EX_OSERR;
1442
1663
ret = seteuid(uid);
1665
perror_plus("seteuid");
1448
1669
strcpy(network.ifr_name, interface);
1449
1670
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1451
perror("ioctl SIOCGIFFLAGS");
1672
perror_plus("ioctl SIOCGIFFLAGS");
1452
1673
#ifdef __linux__
1453
1674
if(restore_loglevel){
1454
1675
ret = klogctl(7, NULL, 0);
1677
perror_plus("klogctl");
1459
1680
#endif /* __linux__ */
1472
1693
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1474
1695
take_down_interface = false;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1696
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1476
1697
exitcode = EX_OSERR;
1477
1698
#ifdef __linux__
1478
1699
if(restore_loglevel){
1479
1700
ret = klogctl(7, NULL, 0);
1702
perror_plus("klogctl");
1484
1705
#endif /* __linux__ */
1487
1708
ret = seteuid(uid);
1710
perror_plus("seteuid");
1494
/* sleep checking until interface is running */
1715
/* Sleep checking until interface is running.
1716
Check every 0.25s, up to total time of delay */
1495
1717
for(int i=0; i < delay * 4; i++){
1496
1718
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1498
perror("ioctl SIOCGIFFLAGS");
1720
perror_plus("ioctl SIOCGIFFLAGS");
1499
1721
} else if(network.ifr_flags & IFF_RUNNING){
1502
1724
struct timespec sleeptime = { .tv_nsec = 250000000 };
1503
1725
ret = nanosleep(&sleeptime, NULL);
1504
1726
if(ret == -1 and errno != EINTR){
1505
perror("nanosleep");
1727
perror_plus("nanosleep");
1508
1730
if(not take_down_interface){
1509
1731
/* We won't need the socket anymore */
1510
1732
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1734
perror_plus("close");
1515
1737
#ifdef __linux__
1691
1912
fprintf(stderr, "Starting Avahi loop search\n");
1694
avahi_simple_poll_loop(mc.simple_poll);
1915
ret = avahi_loop_with_timeout(mc.simple_poll,
1916
(int)(retry_interval * 1000));
1918
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
1919
(ret == 0) ? "successfully" : "with error");
1718
1944
if(gpgme_initialized){
1719
1945
gpgme_release(mc.ctx);
1948
/* Cleans up the circular linked list of Mandos servers the client
1950
if(mc.current_server != NULL){
1951
mc.current_server->prev->next = NULL;
1952
while(mc.current_server != NULL){
1953
server *next = mc.current_server->next;
1954
free(mc.current_server);
1955
mc.current_server = next;
1722
1959
/* Take down the network interface */
1723
1960
if(take_down_interface){
1726
1963
ret = seteuid(0);
1965
perror_plus("seteuid");
1730
1967
if(geteuid() == 0){
1731
1968
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1733
perror("ioctl SIOCGIFFLAGS");
1970
perror_plus("ioctl SIOCGIFFLAGS");
1734
1971
} else if(network.ifr_flags & IFF_UP) {
1735
1972
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1736
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1975
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1741
1978
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1980
perror_plus("close");
1745
1982
/* Lower privileges permanently */
1747
1984
ret = setuid(uid);
1986
perror_plus("setuid");
1754
/* Removes the temp directory used by GPGME */
1991
/* Removes the GPGME temp directory and all files inside */
1755
1992
if(tempdir_created){
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1760
if(errno != ENOENT){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1769
/* Skip "." and ".." */
1770
if(direntry->d_name[0] == '.'
1771
and (direntry->d_name[1] == '\0'
1772
or (direntry->d_name[1] == '.'
1773
and direntry->d_name[2] == '\0'))){
1993
struct dirent **direntries = NULL;
1994
struct dirent *direntry = NULL;
1995
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
1997
for(int i = 0; i < ret; i++){
1998
direntry = direntries[i];
1776
1999
char *fullname = NULL;
1777
2000
ret = asprintf(&fullname, "%s/%s", tempdir,
1778
2001
direntry->d_name);
2003
perror_plus("asprintf");
1783
2006
ret = remove(fullname);