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,
130
131
static const char sys_class_net[] = "/sys/class/net";
131
132
char *connect_to = NULL;
134
/* Doubly linked list that need to be circularly linked when used */
135
typedef struct server{
138
AvahiIfIndex if_index;
140
struct timespec last_seen;
133
145
/* Used for passing in values through the Avahi callback functions */
135
147
AvahiSimplePoll *simple_poll;
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
/* Add server to set of servers to retry periodically */
191
int add_server(const char *ip, uint16_t port,
192
AvahiIfIndex if_index,
195
server *new_server = malloc(sizeof(server));
196
if(new_server == NULL){
197
perror_plus("malloc");
200
*new_server = (server){ .ip = strdup(ip),
202
.if_index = if_index,
204
if(new_server->ip == NULL){
205
perror_plus("strdup");
208
/* Special case of first server */
209
if (mc.current_server == NULL){
210
new_server->next = new_server;
211
new_server->prev = new_server;
212
mc.current_server = new_server;
213
/* Place the new server last in the list */
215
new_server->next = mc.current_server;
216
new_server->prev = mc.current_server->prev;
217
new_server->prev->next = new_server;
218
mc.current_server->prev = new_server;
220
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
222
perror_plus("clock_gettime");
170
229
* Initialize GPGME.
227
/* Set GPGME home directory for the OpenPGP engine only */
286
/* Set GPGME home directory for the OpenPGP engine only */
228
287
rc = gpgme_get_engine_info(&engine_info);
229
288
if(rc != GPG_ERR_NO_ERROR){
230
289
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
425
484
/* OpenPGP credentials */
426
gnutls_certificate_allocate_credentials(&mc.cred);
485
ret = gnutls_certificate_allocate_credentials(&mc.cred);
427
486
if(ret != GNUTLS_E_SUCCESS){
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
487
fprintf(stderr, "GnuTLS memory error: %s\n",
432
488
safer_gnutls_strerror(ret));
433
489
gnutls_global_deinit();
651
707
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
652
708
char interface[IF_NAMESIZE];
653
709
if(if_indextoname((unsigned int)if_index, interface) == NULL){
654
perror("if_indextoname");
710
perror_plus("if_indextoname");
656
712
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
713
ip, interface, port);
1039
1099
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1040
1100
if_entry->d_name);
1102
perror_plus("asprintf");
1045
1105
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1046
1106
if(flags_fd == -1){
1107
perror_plus("open");
1048
1108
free(flagname);
1051
1111
free(flagname);
1052
1112
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1053
1113
/* read line from flags_fd */
1054
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1114
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1055
1115
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1056
1116
flagstring[(size_t)to_read] = '\0';
1057
1117
if(flagstring == NULL){
1118
perror_plus("malloc");
1059
1119
close(flags_fd);
1204
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1206
struct timespec now;
1207
struct timespec waited_time;
1208
intmax_t block_time;
1211
if(mc.current_server == NULL){
1214
"Wait until first server is found. No timeout!\n");
1216
ret = avahi_simple_poll_iterate(s, -1);
1219
fprintf(stderr, "Check current_server if we should run it,"
1222
/* the current time */
1223
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1225
perror_plus("clock_gettime");
1228
/* Calculating in ms how long time between now and server
1229
who we visted longest time ago. Now - last seen. */
1230
waited_time.tv_sec = (now.tv_sec
1231
- mc.current_server->last_seen.tv_sec);
1232
waited_time.tv_nsec = (now.tv_nsec
1233
- mc.current_server->last_seen.tv_nsec);
1234
/* total time is 10s/10,000ms.
1235
Converting to s from ms by dividing by 1,000,
1236
and ns to ms by dividing by 1,000,000. */
1237
block_time = ((retry_interval
1238
- ((intmax_t)waited_time.tv_sec * 1000))
1239
- ((intmax_t)waited_time.tv_nsec / 1000000));
1242
fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);
1245
if(block_time <= 0){
1246
ret = start_mandos_communication(mc.current_server->ip,
1247
mc.current_server->port,
1248
mc.current_server->if_index,
1249
mc.current_server->af);
1251
avahi_simple_poll_quit(mc.simple_poll);
1254
ret = clock_gettime(CLOCK_MONOTONIC,
1255
&mc.current_server->last_seen);
1257
perror_plus("clock_gettime");
1260
mc.current_server = mc.current_server->next;
1261
block_time = 0; /* Call avahi to find new Mandos
1262
servers, but don't block */
1265
ret = avahi_simple_poll_iterate(s, (int)block_time);
1268
if (ret > 0 or errno != EINTR) {
1269
return (ret != 1) ? ret : 0;
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1275
int main(int argc, char *argv[]){
1145
1276
AvahiSServiceBrowser *sb = NULL;
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bool gnutls_initialized = false;
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1295
bool gpgme_initialized = false;
1165
1296
float delay = 2.5f;
1297
double retry_interval = 10; /* 10s between trying a server and
1298
retrying the same server again */
1167
1300
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1168
1301
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1222
1355
.arg = "SECONDS",
1223
1356
.doc = "Maximum delay to wait for interface startup",
1358
{ .name = "retry", .key = 132,
1360
.doc = "Retry interval used when denied by the mandos server",
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1363
* These reproduce what we would get without ARGP_NO_HELP
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1408
if(errno != 0 or tmp == arg or *tmp != '\0'){
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1409
argp_error(state, "Bad delay");
1411
case 132: /* --retry */
1413
retry_interval = strtod(arg, &tmp);
1414
if(errno != 0 or tmp == arg or *tmp != '\0'
1415
or (retry_interval * 1000) > INT_MAX
1416
or retry_interval < 0){
1417
argp_error(state, "Bad retry interval");
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1421
* These reproduce what we would get without ARGP_NO_HELP
1462
/* Work around Debian bug #633582:
1463
<http://bugs.debian.org/633582> */
1466
/* Re-raise priviliges */
1470
perror_plus("seteuid");
1473
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1474
int seckey_fd = open(seckey, O_RDONLY);
1475
if(seckey_fd == -1){
1476
perror_plus("open");
1478
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1480
perror_plus("fstat");
1482
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1483
ret = fchown(seckey_fd, uid, gid);
1485
perror_plus("fchown");
1489
TEMP_FAILURE_RETRY(close(seckey_fd));
1493
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1494
int pubkey_fd = open(pubkey, O_RDONLY);
1495
if(pubkey_fd == -1){
1496
perror_plus("open");
1498
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1500
perror_plus("fstat");
1502
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1503
ret = fchown(pubkey_fd, uid, gid);
1505
perror_plus("fchown");
1509
TEMP_FAILURE_RETRY(close(pubkey_fd));
1513
/* Lower privileges */
1517
perror_plus("seteuid");
1317
1522
avahi_set_log_function(empty_log);
1356
1561
sigemptyset(&sigterm_action.sa_mask);
1357
1562
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1359
perror("sigaddset");
1564
perror_plus("sigaddset");
1360
1565
exitcode = EX_OSERR;
1363
1568
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1365
perror("sigaddset");
1570
perror_plus("sigaddset");
1366
1571
exitcode = EX_OSERR;
1369
1574
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1371
perror("sigaddset");
1576
perror_plus("sigaddset");
1372
1577
exitcode = EX_OSERR;
1379
1584
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1381
perror("sigaction");
1586
perror_plus("sigaction");
1382
1587
return EX_OSERR;
1384
1589
if(old_sigterm_action.sa_handler != SIG_IGN){
1385
1590
ret = sigaction(SIGINT, &sigterm_action, NULL);
1387
perror("sigaction");
1592
perror_plus("sigaction");
1388
1593
exitcode = EX_OSERR;
1392
1597
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1394
perror("sigaction");
1599
perror_plus("sigaction");
1395
1600
return EX_OSERR;
1397
1602
if(old_sigterm_action.sa_handler != SIG_IGN){
1398
1603
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1400
perror("sigaction");
1605
perror_plus("sigaction");
1401
1606
exitcode = EX_OSERR;
1405
1610
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1407
perror("sigaction");
1612
perror_plus("sigaction");
1408
1613
return EX_OSERR;
1410
1615
if(old_sigterm_action.sa_handler != SIG_IGN){
1411
1616
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1413
perror("sigaction");
1618
perror_plus("sigaction");
1414
1619
exitcode = EX_OSERR;
1443
1648
bool restore_loglevel = true;
1445
1650
restore_loglevel = false;
1651
perror_plus("klogctl");
1448
1653
#endif /* __linux__ */
1450
1655
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1657
perror_plus("socket");
1453
1658
exitcode = EX_OSERR;
1454
1659
#ifdef __linux__
1455
1660
if(restore_loglevel){
1456
1661
ret = klogctl(7, NULL, 0);
1663
perror_plus("klogctl");
1461
1666
#endif /* __linux__ */
1464
1669
ret = seteuid(uid);
1671
perror_plus("seteuid");
1470
1675
strcpy(network.ifr_name, interface);
1471
1676
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1473
perror("ioctl SIOCGIFFLAGS");
1678
perror_plus("ioctl SIOCGIFFLAGS");
1474
1679
#ifdef __linux__
1475
1680
if(restore_loglevel){
1476
1681
ret = klogctl(7, NULL, 0);
1683
perror_plus("klogctl");
1481
1686
#endif /* __linux__ */
1494
1699
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1496
1701
take_down_interface = false;
1497
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1702
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1498
1703
exitcode = EX_OSERR;
1499
1704
#ifdef __linux__
1500
1705
if(restore_loglevel){
1501
1706
ret = klogctl(7, NULL, 0);
1708
perror_plus("klogctl");
1506
1711
#endif /* __linux__ */
1509
1714
ret = seteuid(uid);
1716
perror_plus("seteuid");
1516
/* sleep checking until interface is running */
1721
/* Sleep checking until interface is running.
1722
Check every 0.25s, up to total time of delay */
1517
1723
for(int i=0; i < delay * 4; i++){
1518
1724
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1520
perror("ioctl SIOCGIFFLAGS");
1726
perror_plus("ioctl SIOCGIFFLAGS");
1521
1727
} else if(network.ifr_flags & IFF_RUNNING){
1524
1730
struct timespec sleeptime = { .tv_nsec = 250000000 };
1525
1731
ret = nanosleep(&sleeptime, NULL);
1526
1732
if(ret == -1 and errno != EINTR){
1527
perror("nanosleep");
1733
perror_plus("nanosleep");
1530
1736
if(not take_down_interface){
1531
1737
/* We won't need the socket anymore */
1532
1738
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1740
perror_plus("close");
1537
1743
#ifdef __linux__
1630
1836
port = (uint16_t)tmpmax;
1631
1837
*address = '\0';
1632
address = connect_to;
1633
1838
/* Colon in address indicates IPv6 */
1635
if(strchr(address, ':') != NULL){
1840
if(strchr(connect_to, ':') != NULL){
1842
/* Accept [] around IPv6 address - see RFC 5952 */
1843
if(connect_to[0] == '[' and address[-1] == ']')
1851
address = connect_to;
1645
1857
while(not quit_now){
1646
1858
ret = start_mandos_communication(address, port, if_index, af);
1647
1859
if(quit_now or ret == 0){
1863
fprintf(stderr, "Retrying in %d seconds\n",
1864
(int)retry_interval);
1866
sleep((int)retry_interval);
1653
1869
if (not quit_now){
1654
1870
exitcode = EXIT_SUCCESS;
1712
1928
fprintf(stderr, "Starting Avahi loop search\n");
1715
avahi_simple_poll_loop(mc.simple_poll);
1931
ret = avahi_loop_with_timeout(mc.simple_poll,
1932
(int)(retry_interval * 1000));
1934
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
1935
(ret == 0) ? "successfully" : "with error");
1739
1960
if(gpgme_initialized){
1740
1961
gpgme_release(mc.ctx);
1964
/* Cleans up the circular linked list of Mandos servers the client
1966
if(mc.current_server != NULL){
1967
mc.current_server->prev->next = NULL;
1968
while(mc.current_server != NULL){
1969
server *next = mc.current_server->next;
1970
free(mc.current_server);
1971
mc.current_server = next;
1743
1975
/* Take down the network interface */
1744
1976
if(take_down_interface){
1747
1979
ret = seteuid(0);
1981
perror_plus("seteuid");
1751
1983
if(geteuid() == 0){
1752
1984
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1754
perror("ioctl SIOCGIFFLAGS");
1986
perror_plus("ioctl SIOCGIFFLAGS");
1755
1987
} else if(network.ifr_flags & IFF_UP) {
1756
1988
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1757
1989
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1759
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1991
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1762
1994
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1996
perror_plus("close");
1766
1998
/* Lower privileges permanently */
1768
2000
ret = setuid(uid);
2002
perror_plus("setuid");
1776
2008
if(tempdir_created){
1777
2009
struct dirent **direntries = NULL;
1778
2010
struct dirent *direntry = NULL;
1779
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
1781
for(int i = 0; i < ret; i++){
2011
int numentries = scandir(tempdir, &direntries, notdotentries,
2013
if (numentries > 0){
2014
for(int i = 0; i < numentries; i++){
1782
2015
direntry = direntries[i];
1783
2016
char *fullname = NULL;
1784
2017
ret = asprintf(&fullname, "%s/%s", tempdir,
1785
2018
direntry->d_name);
2020
perror_plus("asprintf");
1790
2023
ret = remove(fullname);