62
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
68
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
68
SIOCSIFFLAGS, if_indextoname(),
70
69
if_nametoindex(), IF_NAMESIZE */
151
137
gnutls_dh_params_t dh_params;
152
138
const char *priority;
154
server *current_server;
155
140
} mandos_context;
157
142
/* global context so signal handler can reach it*/
158
143
mandos_context mc = { .simple_poll = NULL, .server = NULL,
159
144
.dh_bits = 1024, .priority = "SECURE256"
160
":!CTYPE-X.509:+CTYPE-OPENPGP",
161
.current_server = NULL };
145
":!CTYPE-X.509:+CTYPE-OPENPGP" };
163
147
sig_atomic_t quit_now = 0;
164
148
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);
174
151
* Make additional room in "buffer" for at least BUFFER_SIZE more
175
152
* bytes. "buffer_capacity" is how much is currently allocated,
187
164
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");
229
168
* Initialize GPGME.
1079
1015
signal_received = sig;
1080
1016
int old_errno = errno;
1081
/* set main loop to exit */
1082
1017
if(mc.simple_poll != NULL){
1083
1018
avahi_simple_poll_quit(mc.simple_poll);
1085
1020
errno = old_errno;
1088
bool get_flags(const char *ifname, struct ifreq *ifr){
1091
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1093
perror_plus("socket");
1096
strcpy(ifr->ifr_name, ifname);
1097
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1100
perror_plus("ioctl SIOCGIFFLAGS");
1107
bool good_flags(const char *ifname, const struct ifreq *ifr){
1109
/* Reject the loopback device */
1110
if(ifr->ifr_flags & IFF_LOOPBACK){
1112
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1117
/* Accept point-to-point devices only if connect_to is specified */
1118
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1120
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1125
/* Otherwise, reject non-broadcast-capable devices */
1126
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1128
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1133
/* Reject non-ARP interfaces (including dummy interfaces) */
1134
if(ifr->ifr_flags & IFF_NOARP){
1136
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n", ifname);
1141
/* Accept this device */
1143
fprintf(stderr, "Interface \"%s\" is good\n", ifname);
1149
* This function determines if a directory entry in /sys/class/net
1150
* corresponds to an acceptable network device.
1151
* (This function is passed to scandir(3) as a filter function.)
1153
int good_interface(const struct dirent *if_entry){
1155
if(if_entry->d_name[0] == '.'){
1160
if(not get_flags(if_entry->d_name, &ifr)){
1164
if(not good_flags(if_entry->d_name, &ifr)){
1170
int notdotentries(const struct dirent *direntry){
1171
/* Skip "." and ".." */
1172
if(direntry->d_name[0] == '.'
1173
and (direntry->d_name[1] == '\0'
1174
or (direntry->d_name[1] == '.'
1175
and direntry->d_name[2] == '\0'))){
1181
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1183
struct timespec now;
1184
struct timespec waited_time;
1185
intmax_t block_time;
1188
if(mc.current_server == NULL){
1191
"Wait until first server is found. No timeout!\n");
1193
ret = avahi_simple_poll_iterate(s, -1);
1196
fprintf(stderr, "Check current_server if we should run it,"
1199
/* the current time */
1200
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1202
perror_plus("clock_gettime");
1205
/* Calculating in ms how long time between now and server
1206
who we visted longest time ago. Now - last seen. */
1207
waited_time.tv_sec = (now.tv_sec
1208
- mc.current_server->last_seen.tv_sec);
1209
waited_time.tv_nsec = (now.tv_nsec
1210
- mc.current_server->last_seen.tv_nsec);
1211
/* total time is 10s/10,000ms.
1212
Converting to s from ms by dividing by 1,000,
1213
and ns to ms by dividing by 1,000,000. */
1214
block_time = ((retry_interval
1215
- ((intmax_t)waited_time.tv_sec * 1000))
1216
- ((intmax_t)waited_time.tv_nsec / 1000000));
1219
fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);
1222
if(block_time <= 0){
1223
ret = start_mandos_communication(mc.current_server->ip,
1224
mc.current_server->port,
1225
mc.current_server->if_index,
1226
mc.current_server->af);
1228
avahi_simple_poll_quit(mc.simple_poll);
1231
ret = clock_gettime(CLOCK_MONOTONIC,
1232
&mc.current_server->last_seen);
1234
perror_plus("clock_gettime");
1237
mc.current_server = mc.current_server->next;
1238
block_time = 0; /* Call avahi to find new Mandos
1239
servers, but don't block */
1242
ret = avahi_simple_poll_iterate(s, (int)block_time);
1245
if (ret > 0 or errno != EINTR) {
1246
return (ret != 1) ? ret : 0;
1252
1023
int main(int argc, char *argv[]){
1253
1024
AvahiSServiceBrowser *sb = NULL;
1439
/* Work around Debian bug #633582:
1440
<http://bugs.debian.org/633582> */
1443
/* Re-raise priviliges */
1447
perror_plus("seteuid");
1450
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1451
int seckey_fd = open(seckey, O_RDONLY);
1452
if(seckey_fd == -1){
1453
perror_plus("open");
1455
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1457
perror_plus("fstat");
1459
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1460
ret = fchown(seckey_fd, uid, gid);
1462
perror_plus("fchown");
1466
TEMP_FAILURE_RETRY(close(seckey_fd));
1470
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1471
int pubkey_fd = open(pubkey, O_RDONLY);
1472
if(pubkey_fd == -1){
1473
perror_plus("open");
1475
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_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(pubkey_fd, uid, gid);
1482
perror_plus("fchown");
1486
TEMP_FAILURE_RETRY(close(pubkey_fd));
1490
/* Lower privileges */
1494
perror_plus("seteuid");
1499
1197
avahi_set_log_function(empty_log);
1502
if(interface[0] == '\0'){
1503
struct dirent **direntries;
1504
ret = scandir(sys_class_net, &direntries, good_interface,
1507
/* Pick the first good interface */
1508
interface = strdup(direntries[0]->d_name);
1510
fprintf(stderr, "Using interface \"%s\"\n", interface);
1512
if(interface == NULL){
1513
perror_plus("malloc");
1515
exitcode = EXIT_FAILURE;
1521
fprintf(stderr, "Could not find a network interface\n");
1522
exitcode = EXIT_FAILURE;
1527
1200
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1528
1201
from the signal handler */
1561
1234
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1563
perror_plus("sigaction");
1236
perror("sigaction");
1564
1237
return EX_OSERR;
1566
1239
if(old_sigterm_action.sa_handler != SIG_IGN){
1567
1240
ret = sigaction(SIGINT, &sigterm_action, NULL);
1569
perror_plus("sigaction");
1242
perror("sigaction");
1570
1243
exitcode = EX_OSERR;
1574
1247
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1576
perror_plus("sigaction");
1249
perror("sigaction");
1577
1250
return EX_OSERR;
1579
1252
if(old_sigterm_action.sa_handler != SIG_IGN){
1580
1253
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1582
perror_plus("sigaction");
1255
perror("sigaction");
1583
1256
exitcode = EX_OSERR;
1587
1260
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1589
perror_plus("sigaction");
1262
perror("sigaction");
1590
1263
return EX_OSERR;
1592
1265
if(old_sigterm_action.sa_handler != SIG_IGN){
1593
1266
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1595
perror_plus("sigaction");
1268
perror("sigaction");
1596
1269
exitcode = EX_OSERR;
1601
1274
/* If the interface is down, bring it up */
1602
if(strcmp(interface, "none") != 0){
1275
if(interface[0] != '\0'){
1603
1276
if_index = (AvahiIfIndex) if_nametoindex(interface);
1604
1277
if(if_index == 0){
1605
1278
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1691
1364
ret = seteuid(uid);
1693
perror_plus("seteuid");
1698
/* Sleep checking until interface is running.
1699
Check every 0.25s, up to total time of delay */
1371
/* sleep checking until interface is running */
1700
1372
for(int i=0; i < delay * 4; i++){
1701
1373
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1703
perror_plus("ioctl SIOCGIFFLAGS");
1375
perror("ioctl SIOCGIFFLAGS");
1704
1376
} else if(network.ifr_flags & IFF_RUNNING){
1707
1379
struct timespec sleeptime = { .tv_nsec = 250000000 };
1708
1380
ret = nanosleep(&sleeptime, NULL);
1709
1381
if(ret == -1 and errno != EINTR){
1710
perror_plus("nanosleep");
1382
perror("nanosleep");
1713
1385
if(not take_down_interface){
1714
1386
/* We won't need the socket anymore */
1715
1387
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1717
perror_plus("close");
1720
1392
#ifdef __linux__
1813
1486
port = (uint16_t)tmpmax;
1814
1487
*address = '\0';
1488
address = connect_to;
1815
1489
/* Colon in address indicates IPv6 */
1817
if(strchr(connect_to, ':') != NULL){
1491
if(strchr(address, ':') != NULL){
1819
/* Accept [] around IPv6 address - see RFC 5952 */
1820
if(connect_to[0] == '[' and address[-1] == ']')
1828
address = connect_to;
1834
while(not quit_now){
1835
ret = start_mandos_communication(address, port, if_index, af);
1836
if(quit_now or ret == 0){
1840
fprintf(stderr, "Retrying in %d seconds\n",
1841
(int)retry_interval);
1843
sleep((int)retry_interval);
1501
ret = start_mandos_communication(address, port, if_index, af);
1507
exitcode = EX_NOHOST;
1510
exitcode = EX_USAGE;
1513
exitcode = EX_IOERR;
1516
exitcode = EX_PROTOCOL;
1519
exitcode = EX_OSERR;
1847
1523
exitcode = EXIT_SUCCESS;
1956
1615
ret = seteuid(0);
1958
perror_plus("seteuid");
1960
1619
if(geteuid() == 0){
1961
1620
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1963
perror_plus("ioctl SIOCGIFFLAGS");
1622
perror("ioctl SIOCGIFFLAGS");
1964
1623
} else if(network.ifr_flags & IFF_UP) {
1965
1624
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1966
1625
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1968
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1627
perror("ioctl SIOCSIFFLAGS");
1971
1630
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1973
perror_plus("close");
1975
1634
/* Lower privileges permanently */
1977
1636
ret = setuid(uid);
1979
perror_plus("setuid");
1984
/* Removes the GPGME temp directory and all files inside */
1643
/* Removes the temp directory used by GPGME */
1985
1644
if(tempdir_created){
1986
struct dirent **direntries = NULL;
1987
struct dirent *direntry = NULL;
1988
int numentries = scandir(tempdir, &direntries, notdotentries,
1990
if (numentries > 0){
1991
for(int i = 0; i < numentries; i++){
1992
direntry = direntries[i];
1646
struct dirent *direntry;
1647
d = opendir(tempdir);
1649
if(errno != ENOENT){
1654
direntry = readdir(d);
1655
if(direntry == NULL){
1658
/* Skip "." and ".." */
1659
if(direntry->d_name[0] == '.'
1660
and (direntry->d_name[1] == '\0'
1661
or (direntry->d_name[1] == '.'
1662
and direntry->d_name[2] == '\0'))){
1993
1665
char *fullname = NULL;
1994
1666
ret = asprintf(&fullname, "%s/%s", tempdir,
1995
1667
direntry->d_name);
1997
perror_plus("asprintf");
2000
1672
ret = remove(fullname);