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;
1089
* This function determines if a directory entry in /sys/class/net
1090
* corresponds to an acceptable network device.
1091
* (This function is passed to scandir(3) as a filter function.)
1093
int good_interface(const struct dirent *if_entry){
1095
char *flagname = NULL;
1096
if(if_entry->d_name[0] == '.'){
1099
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1102
perror_plus("asprintf");
1105
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1107
perror_plus("open");
1112
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1113
/* read line from flags_fd */
1114
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1115
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1116
flagstring[(size_t)to_read] = '\0';
1117
if(flagstring == NULL){
1118
perror_plus("malloc");
1123
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1126
perror_plus("read");
1140
tmpmax = strtoimax(flagstring, &tmp, 0);
1141
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1142
and not (isspace(*tmp)))
1143
or tmpmax != (ifreq_flags)tmpmax){
1145
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1146
flagstring, if_entry->d_name);
1152
ifreq_flags flags = (ifreq_flags)tmpmax;
1153
/* Reject the loopback device */
1154
if(flags & IFF_LOOPBACK){
1156
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1161
/* Accept point-to-point devices only if connect_to is specified */
1162
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1164
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1169
/* Otherwise, reject non-broadcast-capable devices */
1170
if(not (flags & IFF_BROADCAST)){
1172
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1177
/* Reject non-ARP interfaces (including dummy interfaces) */
1178
if(flags & IFF_NOARP){
1180
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1185
/* Accept this device */
1187
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1193
int notdotentries(const struct dirent *direntry){
1194
/* Skip "." and ".." */
1195
if(direntry->d_name[0] == '.'
1196
and (direntry->d_name[1] == '\0'
1197
or (direntry->d_name[1] == '.'
1198
and direntry->d_name[2] == '\0'))){
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;
1275
1023
int main(int argc, char *argv[]){
1276
1024
AvahiSServiceBrowser *sb = NULL;
1462
/* Work around Debian bug #633582:
1463
<http://bugs.debian.org/633582> */
1466
/* Re-raise priviliges */
1470
perror_plus("seteuid");
1473
int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);
1474
if(seckey_fd == -1){
1475
perror_plus("open");
1477
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1479
perror_plus("fstat");
1481
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1482
ret = fchown(seckey_fd, uid, gid);
1484
perror_plus("fchown");
1488
TEMP_FAILURE_RETRY(close(seckey_fd));
1491
int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);
1492
if(pubkey_fd == -1){
1493
perror_plus("open");
1495
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1497
perror_plus("fstat");
1499
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1500
ret = fchown(pubkey_fd, uid, gid);
1502
perror_plus("fchown");
1506
TEMP_FAILURE_RETRY(close(pubkey_fd));
1509
/* Lower privileges */
1513
perror_plus("seteuid");
1518
1197
avahi_set_log_function(empty_log);
1521
if(interface[0] == '\0'){
1522
struct dirent **direntries;
1523
ret = scandir(sys_class_net, &direntries, good_interface,
1526
/* Pick the first good interface */
1527
interface = strdup(direntries[0]->d_name);
1529
fprintf(stderr, "Using interface \"%s\"\n", interface);
1531
if(interface == NULL){
1532
perror_plus("malloc");
1534
exitcode = EXIT_FAILURE;
1540
fprintf(stderr, "Could not find a network interface\n");
1541
exitcode = EXIT_FAILURE;
1546
1200
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1547
1201
from the signal handler */
1580
1234
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1582
perror_plus("sigaction");
1236
perror("sigaction");
1583
1237
return EX_OSERR;
1585
1239
if(old_sigterm_action.sa_handler != SIG_IGN){
1586
1240
ret = sigaction(SIGINT, &sigterm_action, NULL);
1588
perror_plus("sigaction");
1242
perror("sigaction");
1589
1243
exitcode = EX_OSERR;
1593
1247
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1595
perror_plus("sigaction");
1249
perror("sigaction");
1596
1250
return EX_OSERR;
1598
1252
if(old_sigterm_action.sa_handler != SIG_IGN){
1599
1253
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1601
perror_plus("sigaction");
1255
perror("sigaction");
1602
1256
exitcode = EX_OSERR;
1606
1260
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1608
perror_plus("sigaction");
1262
perror("sigaction");
1609
1263
return EX_OSERR;
1611
1265
if(old_sigterm_action.sa_handler != SIG_IGN){
1612
1266
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1614
perror_plus("sigaction");
1268
perror("sigaction");
1615
1269
exitcode = EX_OSERR;
1620
1274
/* If the interface is down, bring it up */
1621
if(strcmp(interface, "none") != 0){
1275
if(interface[0] != '\0'){
1622
1276
if_index = (AvahiIfIndex) if_nametoindex(interface);
1623
1277
if(if_index == 0){
1624
1278
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1710
1364
ret = seteuid(uid);
1712
perror_plus("seteuid");
1717
/* Sleep checking until interface is running.
1718
Check every 0.25s, up to total time of delay */
1371
/* sleep checking until interface is running */
1719
1372
for(int i=0; i < delay * 4; i++){
1720
1373
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1722
perror_plus("ioctl SIOCGIFFLAGS");
1375
perror("ioctl SIOCGIFFLAGS");
1723
1376
} else if(network.ifr_flags & IFF_RUNNING){
1726
1379
struct timespec sleeptime = { .tv_nsec = 250000000 };
1727
1380
ret = nanosleep(&sleeptime, NULL);
1728
1381
if(ret == -1 and errno != EINTR){
1729
perror_plus("nanosleep");
1382
perror("nanosleep");
1732
1385
if(not take_down_interface){
1733
1386
/* We won't need the socket anymore */
1734
1387
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1736
perror_plus("close");
1739
1392
#ifdef __linux__
1975
1615
ret = seteuid(0);
1977
perror_plus("seteuid");
1979
1619
if(geteuid() == 0){
1980
1620
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1982
perror_plus("ioctl SIOCGIFFLAGS");
1622
perror("ioctl SIOCGIFFLAGS");
1983
1623
} else if(network.ifr_flags & IFF_UP) {
1984
1624
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1985
1625
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1987
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1627
perror("ioctl SIOCSIFFLAGS");
1990
1630
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1992
perror_plus("close");
1994
1634
/* Lower privileges permanently */
1996
1636
ret = setuid(uid);
1998
perror_plus("setuid");
2003
/* Removes the GPGME temp directory and all files inside */
1643
/* Removes the temp directory used by GPGME */
2004
1644
if(tempdir_created){
2005
struct dirent **direntries = NULL;
2006
struct dirent *direntry = NULL;
2007
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
2009
for(int i = 0; i < ret; i++){
2010
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'))){
2011
1665
char *fullname = NULL;
2012
1666
ret = asprintf(&fullname, "%s/%s", tempdir,
2013
1667
direntry->d_name);
2015
perror_plus("asprintf");
2018
1672
ret = remove(fullname);