62
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
65
#include <errno.h> /* perror(), errno, program_invocation_short_name */
66
#include <time.h> /* nanosleep(), time(), sleep() */
67
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
68
SIOCSIFFLAGS, if_indextoname(),
69
69
if_nametoindex(), IF_NAMESIZE */
137
150
gnutls_dh_params_t dh_params;
138
151
const char *priority;
153
server *current_server;
140
154
} mandos_context;
142
156
/* global context so signal handler can reach it*/
143
157
mandos_context mc = { .simple_poll = NULL, .server = NULL,
144
158
.dh_bits = 1024, .priority = "SECURE256"
145
":!CTYPE-X.509:+CTYPE-OPENPGP" };
159
":!CTYPE-X.509:+CTYPE-OPENPGP", .current_server = NULL };
147
161
sig_atomic_t quit_now = 0;
148
162
int signal_received = 0;
164
/* Function to use when printing errors */
165
void perror_plus(const char *print_text){
166
fprintf(stderr, "Mandos plugin %s: ", program_invocation_short_name);
151
171
* Make additional room in "buffer" for at least BUFFER_SIZE more
152
172
* bytes. "buffer_capacity" is how much is currently allocated,
164
184
return buffer_capacity;
187
int add_server(const char *ip, uint16_t port,
188
AvahiIfIndex if_index,
191
server *new_server = malloc(sizeof(server));
192
if(new_server == NULL){
193
perror_plus("malloc");
196
*new_server = (server){ .ip = strdup(ip),
198
.if_index = if_index,
200
if(new_server->ip == NULL){
201
perror_plus("strdup");
204
/* uniqe case of first server */
205
if (mc.current_server == NULL){
206
new_server->next = new_server;
207
new_server->prev = new_server;
208
mc.current_server = new_server;
209
/* Placing the new server last in the list */
211
new_server->next = mc.current_server;
212
new_server->prev = mc.current_server->prev;
213
new_server->prev->next = new_server;
214
mc.current_server->prev = new_server;
216
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
218
perror_plus("clock_gettime");
168
225
* Initialize GPGME.
1015
1078
signal_received = sig;
1016
1079
int old_errno = errno;
1080
/* set main loop to exit */
1017
1081
if(mc.simple_poll != NULL){
1018
1082
avahi_simple_poll_quit(mc.simple_poll);
1020
1084
errno = old_errno;
1088
* This function determines if a directory entry in /sys/class/net
1089
* corresponds to an acceptable network device.
1090
* (This function is passed to scandir(3) as a filter function.)
1092
int good_interface(const struct dirent *if_entry){
1094
char *flagname = NULL;
1095
if(if_entry->d_name[0] == '.'){
1098
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1101
perror_plus("asprintf");
1104
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1106
perror_plus("open");
1111
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1112
/* read line from flags_fd */
1113
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1114
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1115
flagstring[(size_t)to_read] = '\0';
1116
if(flagstring == NULL){
1117
perror_plus("malloc");
1122
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1125
perror_plus("read");
1139
tmpmax = strtoimax(flagstring, &tmp, 0);
1140
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1141
and not (isspace(*tmp)))
1142
or tmpmax != (ifreq_flags)tmpmax){
1144
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1145
flagstring, if_entry->d_name);
1151
ifreq_flags flags = (ifreq_flags)tmpmax;
1152
/* Reject the loopback device */
1153
if(flags & IFF_LOOPBACK){
1155
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1163
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (flags & IFF_BROADCAST)){
1171
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(flags & IFF_NOARP){
1179
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1184
/* Accept this device */
1186
fprintf(stderr, "Interface \"%s\" is acceptable\n",
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){
1212
fprintf(stderr, "Wait until first server is found. No timeout!\n");
1214
ret = avahi_simple_poll_iterate(s, -1);
1217
fprintf(stderr, "Check current_server if we should run it, or wait\n");
1219
/* the current time */
1220
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1222
perror_plus("clock_gettime");
1225
/* Calculating in ms how long time between now and server
1226
who we visted longest time ago. Now - last seen. */
1227
waited_time.tv_sec = now.tv_sec - mc.current_server->last_seen.tv_sec;
1228
waited_time.tv_nsec = now.tv_nsec - mc.current_server->last_seen.tv_nsec;
1229
/* total time is 10s/10000ms. Converting to s to ms by 1000/s, and ns to ms by divind by 1000000. */
1230
block_time = (retry_interval - ((intmax_t)waited_time.tv_sec * 1000)) - ((intmax_t)waited_time.tv_nsec / 1000000);
1233
fprintf(stderr, "Blocking for %ld ms\n", block_time);
1236
if(block_time <= 0){
1237
ret = start_mandos_communication(mc.current_server->ip,
1238
mc.current_server->port,
1239
mc.current_server->if_index,
1240
mc.current_server->af);
1242
avahi_simple_poll_quit(mc.simple_poll);
1245
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
1247
perror_plus("clock_gettime");
1250
mc.current_server = mc.current_server->next;
1251
block_time = 0; /* call avahi to find new mandos servers, but dont block */
1254
ret = avahi_simple_poll_iterate(s, (int)block_time);
1257
if (ret > 0 or errno != EINTR) {
1258
return (ret != 1) ? ret : 0;
1023
1264
int main(int argc, char *argv[]){
1024
1265
AvahiSServiceBrowser *sb = NULL;
1234
1511
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1236
perror("sigaction");
1513
perror_plus("sigaction");
1237
1514
return EX_OSERR;
1239
1516
if(old_sigterm_action.sa_handler != SIG_IGN){
1240
1517
ret = sigaction(SIGINT, &sigterm_action, NULL);
1242
perror("sigaction");
1519
perror_plus("sigaction");
1243
1520
exitcode = EX_OSERR;
1247
1524
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1249
perror("sigaction");
1526
perror_plus("sigaction");
1250
1527
return EX_OSERR;
1252
1529
if(old_sigterm_action.sa_handler != SIG_IGN){
1253
1530
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1255
perror("sigaction");
1532
perror_plus("sigaction");
1256
1533
exitcode = EX_OSERR;
1260
1537
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1262
perror("sigaction");
1539
perror_plus("sigaction");
1263
1540
return EX_OSERR;
1265
1542
if(old_sigterm_action.sa_handler != SIG_IGN){
1266
1543
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1268
perror("sigaction");
1545
perror_plus("sigaction");
1269
1546
exitcode = EX_OSERR;
1274
1551
/* If the interface is down, bring it up */
1275
if(interface[0] != '\0'){
1552
if(strcmp(interface, "none") != 0){
1276
1553
if_index = (AvahiIfIndex) if_nametoindex(interface);
1277
1554
if(if_index == 0){
1278
1555
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1364
1641
ret = seteuid(uid);
1643
perror_plus("seteuid");
1371
/* sleep checking until interface is running */
1648
/* sleep checking until interface is running. Check every 0.25s, up to total time of delay */
1372
1649
for(int i=0; i < delay * 4; i++){
1373
1650
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1375
perror("ioctl SIOCGIFFLAGS");
1652
perror_plus("ioctl SIOCGIFFLAGS");
1376
1653
} else if(network.ifr_flags & IFF_RUNNING){
1379
1656
struct timespec sleeptime = { .tv_nsec = 250000000 };
1380
1657
ret = nanosleep(&sleeptime, NULL);
1381
1658
if(ret == -1 and errno != EINTR){
1382
perror("nanosleep");
1659
perror_plus("nanosleep");
1385
1662
if(not take_down_interface){
1386
1663
/* We won't need the socket anymore */
1387
1664
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1666
perror_plus("close");
1392
1669
#ifdef __linux__
1615
1893
ret = seteuid(0);
1895
perror_plus("seteuid");
1619
1897
if(geteuid() == 0){
1620
1898
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1622
perror("ioctl SIOCGIFFLAGS");
1900
perror_plus("ioctl SIOCGIFFLAGS");
1623
1901
} else if(network.ifr_flags & IFF_UP) {
1624
1902
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1625
1903
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1627
perror("ioctl SIOCSIFFLAGS");
1905
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1630
1908
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1910
perror_plus("close");
1634
1912
/* Lower privileges permanently */
1636
1914
ret = setuid(uid);
1916
perror_plus("setuid");
1643
/* Removes the temp directory used by GPGME */
1921
/* Removes the GPGME temp directory and all files inside */
1644
1922
if(tempdir_created){
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'))){
1923
struct dirent **direntries = NULL;
1924
struct dirent *direntry = NULL;
1925
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
1927
for(int i = 0; i < ret; i++){
1928
direntry = direntries[i];
1665
1929
char *fullname = NULL;
1666
1930
ret = asprintf(&fullname, "%s/%s", tempdir,
1667
1931
direntry->d_name);
1933
perror_plus("asprintf");
1672
1936
ret = remove(fullname);