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,
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,
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
135
gnutls_dh_params_t dh_params;
152
136
const char *priority;
154
server *current_server;
155
138
} mandos_context;
157
140
/* global context so signal handler can reach it*/
158
141
mandos_context mc = { .simple_poll = NULL, .server = NULL,
159
142
.dh_bits = 1024, .priority = "SECURE256"
160
":!CTYPE-X.509:+CTYPE-OPENPGP",
161
.current_server = NULL };
163
sig_atomic_t quit_now = 0;
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);
143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
174
146
* Make additional room in "buffer" for at least BUFFER_SIZE more
187
159
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
163
* Initialize GPGME.
1079
971
signal_received = sig;
1080
972
int old_errno = errno;
1081
/* set main loop to exit */
1082
973
if(mc.simple_poll != NULL){
1083
974
avahi_simple_poll_quit(mc.simple_poll);
1085
976
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
979
int main(int argc, char *argv[]){
1253
980
AvahiSServiceBrowser *sb = NULL;
1332
1058
.arg = "SECONDS",
1333
1059
.doc = "Maximum delay to wait for interface startup",
1335
{ .name = "retry", .key = 132,
1337
.doc = "Retry interval used when denied by the mandos server",
1340
* These reproduce what we would get without ARGP_NO_HELP
1342
{ .name = "help", .key = '?',
1343
.doc = "Give this help list", .group = -1 },
1344
{ .name = "usage", .key = -3,
1345
.doc = "Give a short usage message", .group = -1 },
1346
{ .name = "version", .key = 'V',
1347
.doc = "Print program version", .group = -1 },
1348
1061
{ .name = NULL }
1351
1064
error_t parse_opt(int key, char *arg,
1352
1065
struct argp_state *state){
1355
1067
case 128: /* --debug */
1384
1097
delay = strtof(arg, &tmp);
1385
1098
if(errno != 0 or tmp == arg or *tmp != '\0'){
1386
argp_error(state, "Bad delay");
1388
case 132: /* --retry */
1390
retry_interval = strtod(arg, &tmp);
1391
if(errno != 0 or tmp == arg or *tmp != '\0'
1392
or (retry_interval * 1000) > INT_MAX
1393
or retry_interval < 0){
1394
argp_error(state, "Bad retry interval");
1099
fprintf(stderr, "Bad delay\n");
1398
* These reproduce what we would get without ARGP_NO_HELP
1400
case '?': /* --help */
1401
argp_state_help(state, state->out_stream,
1402
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1403
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1404
case -3: /* --usage */
1405
argp_state_help(state, state->out_stream,
1406
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1407
case 'V': /* --version */
1408
fprintf(state->out_stream, "%s\n", argp_program_version);
1409
exit(argp_err_exit_status);
1412
1108
return ARGP_ERR_UNKNOWN;
1417
1113
struct argp argp = { .options = options, .parser = parse_opt,
1418
1114
.args_doc = "",
1419
1115
.doc = "Mandos client -- Get and decrypt"
1420
1116
" passwords from a Mandos server" };
1421
ret = argp_parse(&argp, argc, argv,
1422
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1429
perror_plus("argp_parse");
1430
exitcode = EX_OSERR;
1433
exitcode = EX_USAGE;
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");
1117
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1118
if(ret == ARGP_ERR_UNKNOWN){
1119
fprintf(stderr, "Unknown error while parsing arguments\n");
1120
exitcode = EXIT_FAILURE;
1499
1126
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
1129
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1528
1130
from the signal handler */
1561
1163
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1563
perror_plus("sigaction");
1165
perror("sigaction");
1166
return EXIT_FAILURE;
1566
1168
if(old_sigterm_action.sa_handler != SIG_IGN){
1567
1169
ret = sigaction(SIGINT, &sigterm_action, NULL);
1569
perror_plus("sigaction");
1570
exitcode = EX_OSERR;
1171
perror("sigaction");
1172
exitcode = EXIT_FAILURE;
1574
1176
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1576
perror_plus("sigaction");
1178
perror("sigaction");
1179
return EXIT_FAILURE;
1579
1181
if(old_sigterm_action.sa_handler != SIG_IGN){
1580
1182
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1582
perror_plus("sigaction");
1583
exitcode = EX_OSERR;
1184
perror("sigaction");
1185
exitcode = EXIT_FAILURE;
1587
1189
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1589
perror_plus("sigaction");
1191
perror("sigaction");
1192
return EXIT_FAILURE;
1592
1194
if(old_sigterm_action.sa_handler != SIG_IGN){
1593
1195
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1595
perror_plus("sigaction");
1596
exitcode = EX_OSERR;
1197
perror("sigaction");
1198
exitcode = EXIT_FAILURE;
1601
1203
/* If the interface is down, bring it up */
1602
if(strcmp(interface, "none") != 0){
1204
if(interface[0] != '\0'){
1603
1205
if_index = (AvahiIfIndex) if_nametoindex(interface);
1604
1206
if(if_index == 0){
1605
1207
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1606
exitcode = EX_UNAVAILABLE;
1208
exitcode = EXIT_FAILURE;
1691
1293
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 */
1300
/* sleep checking until interface is running */
1700
1301
for(int i=0; i < delay * 4; i++){
1701
1302
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1703
perror_plus("ioctl SIOCGIFFLAGS");
1304
perror("ioctl SIOCGIFFLAGS");
1704
1305
} else if(network.ifr_flags & IFF_RUNNING){
1707
1308
struct timespec sleeptime = { .tv_nsec = 250000000 };
1708
1309
ret = nanosleep(&sleeptime, NULL);
1709
1310
if(ret == -1 and errno != EINTR){
1710
perror_plus("nanosleep");
1311
perror("nanosleep");
1713
1314
if(not take_down_interface){
1714
1315
/* We won't need the socket anymore */
1715
1316
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1717
perror_plus("close");
1720
1321
#ifdef __linux__
1813
1415
port = (uint16_t)tmpmax;
1814
1416
*address = '\0';
1417
address = connect_to;
1815
1418
/* Colon in address indicates IPv6 */
1817
if(strchr(connect_to, ':') != NULL){
1420
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);
1430
ret = start_mandos_communication(address, port, if_index, af);
1432
exitcode = EXIT_FAILURE;
1847
1434
exitcode = EXIT_SUCCESS;
1956
1526
ret = seteuid(0);
1958
perror_plus("seteuid");
1960
1530
if(geteuid() == 0){
1961
1531
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1963
perror_plus("ioctl SIOCGIFFLAGS");
1533
perror("ioctl SIOCGIFFLAGS");
1964
1534
} else if(network.ifr_flags & IFF_UP) {
1965
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1535
network.ifr_flags &= ~IFF_UP; /* clear flag */
1966
1536
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1968
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1538
perror("ioctl SIOCSIFFLAGS");
1971
1541
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1973
perror_plus("close");
1975
1545
/* Lower privileges permanently */
1977
1547
ret = setuid(uid);
1979
perror_plus("setuid");
1984
/* Removes the GPGME temp directory and all files inside */
1554
/* Removes the temp directory used by GPGME */
1985
1555
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];
1557
struct dirent *direntry;
1558
d = opendir(tempdir);
1560
if(errno != ENOENT){
1565
direntry = readdir(d);
1566
if(direntry == NULL){
1569
/* Skip "." and ".." */
1570
if(direntry->d_name[0] == '.'
1571
and (direntry->d_name[1] == '\0'
1572
or (direntry->d_name[1] == '.'
1573
and direntry->d_name[2] == '\0'))){
1993
1576
char *fullname = NULL;
1994
1577
ret = asprintf(&fullname, "%s/%s", tempdir,
1995
1578
direntry->d_name);
1997
perror_plus("asprintf");
2000
1583
ret = remove(fullname);