43
43
stdout, ferror(), remove() */
44
44
#include <stdint.h> /* uint16_t, uint32_t */
45
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
srand(), strtof(), abort() */
48
48
#include <stdbool.h> /* bool, false, true */
49
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
50
strerror(), asprintf(), strcpy() */
62
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno, program_invocation_short_name */
66
#include <time.h> /* nanosleep(), time(), sleep() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
67
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
68
SIOCSIFFLAGS, if_indextoname(),
69
69
if_nametoindex(), IF_NAMESIZE */
150
136
gnutls_dh_params_t dh_params;
151
137
const char *priority;
153
server *current_server;
154
139
} mandos_context;
156
141
/* global context so signal handler can reach it*/
157
142
mandos_context mc = { .simple_poll = NULL, .server = NULL,
158
143
.dh_bits = 1024, .priority = "SECURE256"
159
":!CTYPE-X.509:+CTYPE-OPENPGP", .current_server = NULL };
144
":!CTYPE-X.509:+CTYPE-OPENPGP" };
161
146
sig_atomic_t quit_now = 0;
162
147
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);
171
150
* Make additional room in "buffer" for at least BUFFER_SIZE more
172
151
* bytes. "buffer_capacity" is how much is currently allocated,
184
163
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");
225
167
* Initialize GPGME.
1078
970
signal_received = sig;
1079
971
int old_errno = errno;
1080
/* set main loop to exit */
1081
972
if(mc.simple_poll != NULL){
1082
973
avahi_simple_poll_quit(mc.simple_poll);
1084
975
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;
1264
978
int main(int argc, char *argv[]){
1265
979
AvahiSServiceBrowser *sb = NULL;
1481
1159
mc.simple_poll = avahi_simple_poll_new();
1482
1160
if(mc.simple_poll == NULL){
1483
1161
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1484
exitcode = EX_UNAVAILABLE;
1162
exitcode = EXIT_FAILURE;
1488
1166
sigemptyset(&sigterm_action.sa_mask);
1489
1167
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1491
perror_plus("sigaddset");
1492
exitcode = EX_OSERR;
1169
perror("sigaddset");
1170
exitcode = EXIT_FAILURE;
1495
1173
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1497
perror_plus("sigaddset");
1498
exitcode = EX_OSERR;
1175
perror("sigaddset");
1176
exitcode = EXIT_FAILURE;
1501
1179
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1503
perror_plus("sigaddset");
1504
exitcode = EX_OSERR;
1181
perror("sigaddset");
1182
exitcode = EXIT_FAILURE;
1507
1185
/* Need to check if the handler is SIG_IGN before handling:
1511
1189
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1513
perror_plus("sigaction");
1191
perror("sigaction");
1192
return EXIT_FAILURE;
1516
1194
if(old_sigterm_action.sa_handler != SIG_IGN){
1517
1195
ret = sigaction(SIGINT, &sigterm_action, NULL);
1519
perror_plus("sigaction");
1520
exitcode = EX_OSERR;
1197
perror("sigaction");
1198
exitcode = EXIT_FAILURE;
1524
1202
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1526
perror_plus("sigaction");
1204
perror("sigaction");
1205
return EXIT_FAILURE;
1529
1207
if(old_sigterm_action.sa_handler != SIG_IGN){
1530
1208
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1532
perror_plus("sigaction");
1533
exitcode = EX_OSERR;
1210
perror("sigaction");
1211
exitcode = EXIT_FAILURE;
1537
1215
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1539
perror_plus("sigaction");
1217
perror("sigaction");
1218
return EXIT_FAILURE;
1542
1220
if(old_sigterm_action.sa_handler != SIG_IGN){
1543
1221
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1545
perror_plus("sigaction");
1546
exitcode = EX_OSERR;
1223
perror("sigaction");
1224
exitcode = EXIT_FAILURE;
1551
1229
/* If the interface is down, bring it up */
1552
if(strcmp(interface, "none") != 0){
1230
if(interface[0] != '\0'){
1553
1231
if_index = (AvahiIfIndex) if_nametoindex(interface);
1554
1232
if(if_index == 0){
1555
1233
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1556
exitcode = EX_UNAVAILABLE;
1234
exitcode = EXIT_FAILURE;
1641
1319
ret = seteuid(uid);
1643
perror_plus("seteuid");
1648
/* sleep checking until interface is running. Check every 0.25s, up to total time of delay */
1326
/* sleep checking until interface is running */
1649
1327
for(int i=0; i < delay * 4; i++){
1650
1328
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1652
perror_plus("ioctl SIOCGIFFLAGS");
1330
perror("ioctl SIOCGIFFLAGS");
1653
1331
} else if(network.ifr_flags & IFF_RUNNING){
1656
1334
struct timespec sleeptime = { .tv_nsec = 250000000 };
1657
1335
ret = nanosleep(&sleeptime, NULL);
1658
1336
if(ret == -1 and errno != EINTR){
1659
perror_plus("nanosleep");
1337
perror("nanosleep");
1662
1340
if(not take_down_interface){
1663
1341
/* We won't need the socket anymore */
1664
1342
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1666
perror_plus("close");
1669
1347
#ifdef __linux__
1893
1552
ret = seteuid(0);
1895
perror_plus("seteuid");
1897
1556
if(geteuid() == 0){
1898
1557
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1900
perror_plus("ioctl SIOCGIFFLAGS");
1559
perror("ioctl SIOCGIFFLAGS");
1901
1560
} else if(network.ifr_flags & IFF_UP) {
1902
1561
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1903
1562
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1905
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1564
perror("ioctl SIOCSIFFLAGS");
1908
1567
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1910
perror_plus("close");
1912
1571
/* Lower privileges permanently */
1914
1573
ret = setuid(uid);
1916
perror_plus("setuid");
1921
/* Removes the GPGME temp directory and all files inside */
1580
/* Removes the temp directory used by GPGME */
1922
1581
if(tempdir_created){
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];
1583
struct dirent *direntry;
1584
d = opendir(tempdir);
1586
if(errno != ENOENT){
1591
direntry = readdir(d);
1592
if(direntry == NULL){
1595
/* Skip "." and ".." */
1596
if(direntry->d_name[0] == '.'
1597
and (direntry->d_name[1] == '\0'
1598
or (direntry->d_name[1] == '.'
1599
and direntry->d_name[2] == '\0'))){
1929
1602
char *fullname = NULL;
1930
1603
ret = asprintf(&fullname, "%s/%s", tempdir,
1931
1604
direntry->d_name);
1933
perror_plus("asprintf");
1936
1609
ret = remove(fullname);