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, EXIT_FAILURE,
47
srand(), strtof(), abort() */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
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48
#include <stdbool.h> /* bool, false, true */
49
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
50
strerror(), asprintf(), strcpy() */
64
64
#include <assert.h> /* assert() */
65
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
66
#include <time.h> /* nanosleep(), time(), sleep() */
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67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
68
SIOCSIFFLAGS, if_indextoname(),
69
69
if_nametoindex(), IF_NAMESIZE */
82
82
#include <signal.h> /* sigemptyset(), sigaddset(),
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83
sigaction(), SIGTERM, sig_atomic_t,
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE */
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
88
89
#include <sys/klog.h> /* klogctl() */
126
127
static const char mandos_protocol_version[] = "1";
127
128
const char *argp_program_version = "mandos-client " VERSION;
128
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
130
static const char sys_class_net[] = "/sys/class/net";
131
char *connect_to = NULL;
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133
/* Used for passing in values through the Avahi callback functions */
975
1024
errno = old_errno;
1028
* This function determines if a directory entry in /sys/class/net
1029
* corresponds to an acceptable network device.
1030
* (This function is passed to scandir(3) as a filter function.)
1032
int good_interface(const struct dirent *if_entry){
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1041
if(if_entry->d_name[0] == '.'){
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1049
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1050
/* read line from flags_fd */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1052
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1053
flagstring[(size_t)to_read] = '\0';
1054
if(flagstring == NULL){
1060
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1077
tmpmax = strtoimax(flagstring, &tmp, 0);
1078
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1079
and not (isspace(*tmp)))
1080
or tmpmax != (ifreq_flags)tmpmax){
1082
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1083
flagstring, if_entry->d_name);
1089
ifreq_flags flags = (ifreq_flags)tmpmax;
1090
/* Reject the loopback device */
1091
if(flags & IFF_LOOPBACK){
1093
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1098
/* Accept point-to-point devices only if connect_to is specified */
1099
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1101
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1106
/* Otherwise, reject non-broadcast-capable devices */
1107
if(not (flags & IFF_BROADCAST)){
1109
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1114
/* Accept this device */
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
978
1122
int main(int argc, char *argv[]){
979
1123
AvahiSServiceBrowser *sb = NULL;
982
1126
intmax_t tmpmax;
984
1128
int exitcode = EXIT_SUCCESS;
985
const char *interface = "eth0";
1129
const char *interface = "";
986
1130
struct ifreq network;
988
1132
bool take_down_interface = false;
991
char *connect_to = NULL;
992
1135
char tempdir[] = "/tmp/mandosXXXXXX";
993
1136
bool tempdir_created = false;
994
1137
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1152
1295
avahi_set_log_function(empty_log);
1298
if(interface[0] == '\0'){
1299
struct dirent **direntries;
1300
ret = scandir(sys_class_net, &direntries, good_interface,
1303
/* Pick the first good interface */
1304
interface = strdup(direntries[0]->d_name);
1306
fprintf(stderr, "Using interface \"%s\"\n", interface);
1308
if(interface == NULL){
1311
exitcode = EXIT_FAILURE;
1317
fprintf(stderr, "Could not find a network interface\n");
1318
exitcode = EXIT_FAILURE;
1155
1323
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1156
1324
from the signal handler */
1167
1335
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1169
1337
perror("sigaddset");
1170
exitcode = EXIT_FAILURE;
1338
exitcode = EX_OSERR;
1173
1341
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1175
1343
perror("sigaddset");
1176
exitcode = EXIT_FAILURE;
1344
exitcode = EX_OSERR;
1179
1347
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1181
1349
perror("sigaddset");
1182
exitcode = EXIT_FAILURE;
1350
exitcode = EX_OSERR;
1185
1353
/* Need to check if the handler is SIG_IGN before handling:
1189
1357
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1191
1359
perror("sigaction");
1192
return EXIT_FAILURE;
1194
1362
if(old_sigterm_action.sa_handler != SIG_IGN){
1195
1363
ret = sigaction(SIGINT, &sigterm_action, NULL);
1197
1365
perror("sigaction");
1198
exitcode = EXIT_FAILURE;
1366
exitcode = EX_OSERR;
1202
1370
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1204
1372
perror("sigaction");
1205
return EXIT_FAILURE;
1207
1375
if(old_sigterm_action.sa_handler != SIG_IGN){
1208
1376
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1210
1378
perror("sigaction");
1211
exitcode = EXIT_FAILURE;
1379
exitcode = EX_OSERR;
1215
1383
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1217
1385
perror("sigaction");
1218
return EXIT_FAILURE;
1220
1388
if(old_sigterm_action.sa_handler != SIG_IGN){
1221
1389
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1223
1391
perror("sigaction");
1224
exitcode = EXIT_FAILURE;
1392
exitcode = EX_OSERR;
1229
1397
/* If the interface is down, bring it up */
1230
if(interface[0] != '\0'){
1398
if(strcmp(interface, "none") != 0){
1231
1399
if_index = (AvahiIfIndex) if_nametoindex(interface);
1232
1400
if(if_index == 0){
1233
1401
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1234
exitcode = EXIT_FAILURE;
1402
exitcode = EX_UNAVAILABLE;
1304
1472
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1306
1474
take_down_interface = false;
1307
perror("ioctl SIOCSIFFLAGS");
1308
exitcode = EXIT_FAILURE;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1476
exitcode = EX_OSERR;
1309
1477
#ifdef __linux__
1310
1478
if(restore_loglevel){
1311
1479
ret = klogctl(7, NULL, 0);
1401
1569
if(not init_gpgme(pubkey, seckey, tempdir)){
1402
1570
fprintf(stderr, "init_gpgme failed\n");
1403
exitcode = EXIT_FAILURE;
1571
exitcode = EX_UNAVAILABLE;
1406
1574
gpgme_initialized = true;
1456
ret = start_mandos_communication(address, port, if_index, af);
1458
exitcode = EXIT_FAILURE;
1624
while(not quit_now){
1625
ret = start_mandos_communication(address, port, if_index, af);
1626
if(quit_now or ret == 0){
1460
1633
exitcode = EXIT_SUCCESS;
1561
1735
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1562
1736
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1564
perror("ioctl SIOCSIFFLAGS");
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1567
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));