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,
68
69
SIOCSIFFLAGS, if_indextoname(),
73
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
75
getuid(), getgid(), seteuid(),
75
76
setgid(), pause() */
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
77
78
#include <iso646.h> /* not, or, and */
78
79
#include <argp.h> /* struct argp_option, error_t, struct
79
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;
216
new_server->prev->next = new_server;
217
mc.current_server->prev = new_server;
219
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
221
perror_plus("clock_gettime");
170
228
* Initialize GPGME.
425
483
/* OpenPGP credentials */
426
gnutls_certificate_allocate_credentials(&mc.cred);
484
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",
432
487
safer_gnutls_strerror(ret));
433
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");
709
perror_plus("if_indextoname");
656
711
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
712
ip, interface, port);
1038
1098
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1039
1099
if_entry->d_name);
1101
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");
1047
1107
free(flagname);
1050
1110
free(flagname);
1051
1111
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1052
1112
/* read line from flags_fd */
1053
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1113
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1054
1114
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1055
1115
flagstring[(size_t)to_read] = '\0';
1056
1116
if(flagstring == NULL){
1117
perror_plus("malloc");
1058
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;
1206
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");
1215
ret = avahi_simple_poll_iterate(s, -1);
1218
fprintf(stderr, "Check current_server if we should run it,"
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/* the current time */
1222
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1224
perror_plus("clock_gettime");
1227
/* Calculating in ms how long time between now and server
1228
who we visted longest time ago. Now - last seen. */
1229
waited_time.tv_sec = (now.tv_sec
1230
- mc.current_server->last_seen.tv_sec);
1231
waited_time.tv_nsec = (now.tv_nsec
1232
- mc.current_server->last_seen.tv_nsec);
1233
/* 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));
1241
fprintf(stderr, "Blocking for %ld ms\n", block_time);
1244
if(block_time <= 0){
1245
ret = start_mandos_communication(mc.current_server->ip,
1246
mc.current_server->port,
1247
mc.current_server->if_index,
1248
mc.current_server->af);
1250
avahi_simple_poll_quit(mc.simple_poll);
1253
ret = clock_gettime(CLOCK_MONOTONIC,
1254
&mc.current_server->last_seen);
1256
perror_plus("clock_gettime");
1259
mc.current_server = mc.current_server->next;
1260
block_time = 0; /* Call avahi to find new Mandos
1261
servers, but don't block */
1264
ret = avahi_simple_poll_iterate(s, (int)block_time);
1267
if (ret > 0 or errno != EINTR) {
1268
return (ret != 1) ? ret : 0;
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1274
int main(int argc, char *argv[]){
1133
1275
AvahiSServiceBrowser *sb = NULL;
1151
1293
bool gnutls_initialized = false;
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1294
bool gpgme_initialized = false;
1153
1295
float delay = 2.5f;
1296
double retry_interval = 10; /* 10s between trying a server and
1297
retrying the same server again */
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struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
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1300
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
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1407
if(errno != 0 or tmp == arg or *tmp != '\0'){
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1408
argp_error(state, "Bad delay");
1410
case 132: /* --retry */
1412
retry_interval = strtod(arg, &tmp);
1413
if(errno != 0 or tmp == arg or *tmp != '\0'
1414
or (retry_interval * 1000) > INT_MAX){
1415
argp_error(state, "Bad retry interval");
1264
1419
* These reproduce what we would get without ARGP_NO_HELP
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/* Work around Debian bug #633582:
1461
<http://bugs.debian.org/633582> */
1464
/* Re-raise priviliges */
1468
perror_plus("seteuid");
1471
int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);
1472
if(seckey_fd == -1){
1473
perror_plus("open");
1475
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1477
perror_plus("fstat");
1479
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1480
ret = fchown(seckey_fd, uid, gid);
1482
perror_plus("fchown");
1486
TEMP_FAILURE_RETRY(close(seckey_fd));
1489
int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);
1490
if(pubkey_fd == -1){
1491
perror_plus("open");
1493
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1495
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));
1507
/* Lower privileges */
1511
perror_plus("seteuid");
1305
1516
avahi_set_log_function(empty_log);
1344
1555
sigemptyset(&sigterm_action.sa_mask);
1345
1556
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1347
perror("sigaddset");
1558
perror_plus("sigaddset");
1348
1559
exitcode = EX_OSERR;
1351
1562
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1353
perror("sigaddset");
1564
perror_plus("sigaddset");
1354
1565
exitcode = EX_OSERR;
1357
1568
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1359
perror("sigaddset");
1570
perror_plus("sigaddset");
1360
1571
exitcode = EX_OSERR;
1367
1578
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1369
perror("sigaction");
1580
perror_plus("sigaction");
1370
1581
return EX_OSERR;
1372
1583
if(old_sigterm_action.sa_handler != SIG_IGN){
1373
1584
ret = sigaction(SIGINT, &sigterm_action, NULL);
1375
perror("sigaction");
1586
perror_plus("sigaction");
1376
1587
exitcode = EX_OSERR;
1380
1591
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1382
perror("sigaction");
1593
perror_plus("sigaction");
1383
1594
return EX_OSERR;
1385
1596
if(old_sigterm_action.sa_handler != SIG_IGN){
1386
1597
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1388
perror("sigaction");
1599
perror_plus("sigaction");
1389
1600
exitcode = EX_OSERR;
1393
1604
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1395
perror("sigaction");
1606
perror_plus("sigaction");
1396
1607
return EX_OSERR;
1398
1609
if(old_sigterm_action.sa_handler != SIG_IGN){
1399
1610
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1401
perror("sigaction");
1612
perror_plus("sigaction");
1402
1613
exitcode = EX_OSERR;
1452
1663
ret = seteuid(uid);
1665
perror_plus("seteuid");
1458
1669
strcpy(network.ifr_name, interface);
1459
1670
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1461
perror("ioctl SIOCGIFFLAGS");
1672
perror_plus("ioctl SIOCGIFFLAGS");
1462
1673
#ifdef __linux__
1463
1674
if(restore_loglevel){
1464
1675
ret = klogctl(7, NULL, 0);
1677
perror_plus("klogctl");
1469
1680
#endif /* __linux__ */
1482
1693
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1484
1695
take_down_interface = false;
1485
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1696
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1486
1697
exitcode = EX_OSERR;
1487
1698
#ifdef __linux__
1488
1699
if(restore_loglevel){
1489
1700
ret = klogctl(7, NULL, 0);
1702
perror_plus("klogctl");
1494
1705
#endif /* __linux__ */
1497
1708
ret = seteuid(uid);
1710
perror_plus("seteuid");
1504
/* sleep checking until interface is running */
1715
/* Sleep checking until interface is running.
1716
Check every 0.25s, up to total time of delay */
1505
1717
for(int i=0; i < delay * 4; i++){
1506
1718
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1508
perror("ioctl SIOCGIFFLAGS");
1720
perror_plus("ioctl SIOCGIFFLAGS");
1509
1721
} else if(network.ifr_flags & IFF_RUNNING){
1512
1724
struct timespec sleeptime = { .tv_nsec = 250000000 };
1513
1725
ret = nanosleep(&sleeptime, NULL);
1514
1726
if(ret == -1 and errno != EINTR){
1515
perror("nanosleep");
1727
perror_plus("nanosleep");
1518
1730
if(not take_down_interface){
1519
1731
/* We won't need the socket anymore */
1520
1732
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1734
perror_plus("close");
1525
1737
#ifdef __linux__
1701
1912
fprintf(stderr, "Starting Avahi loop search\n");
1704
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");
1728
1944
if(gpgme_initialized){
1729
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;
1732
1959
/* Take down the network interface */
1733
1960
if(take_down_interface){
1736
1963
ret = seteuid(0);
1965
perror_plus("seteuid");
1740
1967
if(geteuid() == 0){
1741
1968
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1743
perror("ioctl SIOCGIFFLAGS");
1970
perror_plus("ioctl SIOCGIFFLAGS");
1744
1971
} else if(network.ifr_flags & IFF_UP) {
1745
1972
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1746
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1748
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1975
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1751
1978
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1980
perror_plus("close");
1755
1982
/* Lower privileges permanently */
1757
1984
ret = setuid(uid);
1986
perror_plus("setuid");
1764
/* Removes the temp directory used by GPGME */
1991
/* Removes the GPGME temp directory and all files inside */
1765
1992
if(tempdir_created){
1767
struct dirent *direntry;
1768
d = opendir(tempdir);
1770
if(errno != ENOENT){
1775
direntry = readdir(d);
1776
if(direntry == NULL){
1779
/* Skip "." and ".." */
1780
if(direntry->d_name[0] == '.'
1781
and (direntry->d_name[1] == '\0'
1782
or (direntry->d_name[1] == '.'
1783
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];
1786
1999
char *fullname = NULL;
1787
2000
ret = asprintf(&fullname, "%s/%s", tempdir,
1788
2001
direntry->d_name);
2003
perror_plus("asprintf");
1793
2006
ret = remove(fullname);