43
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stdout, ferror(), remove() */
44
44
#include <stdint.h> /* uint16_t, uint32_t */
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#include <stddef.h> /* NULL, size_t, ssize_t */
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#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
srand(), strtof(), abort() */
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#include <stdbool.h> /* bool, false, true */
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#include <string.h> /* memset(), strcmp(), strlen(),
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strerror(), asprintf(), strcpy() */
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#include <signal.h> /* sigemptyset(), sigaddset(),
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sigaction(), SIGTERM, sig_atomic_t,
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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
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#include <sysexits.h> /* EX_OSERR, EX_USAGE */
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#include <sys/klog.h> /* klogctl() */
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static const char mandos_protocol_version[] = "1";
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const char *argp_program_version = "mandos-client " VERSION;
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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static const char sys_class_net[] = "/sys/class/net";
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char *connect_to = NULL;
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/* Used for passing in values through the Avahi callback functions */
1022
975
errno = old_errno;
1026
* This function determines if a directory entry in /sys/class/net
1027
* corresponds to an acceptable network device.
1028
* (This function is passed to scandir(3) as a filter function.)
1030
int good_interface(const struct dirent *if_entry){
1032
char *flagname = NULL;
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int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1039
if(if_entry->d_name[0] == '.'){
1042
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1047
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1048
/* read line from flags_fd */
1049
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1050
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1051
flagstring[(size_t)to_read] = '\0';
1052
if(flagstring == NULL){
1058
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1075
tmpmax = strtoimax(flagstring, &tmp, 0);
1076
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1077
and not (isspace(*tmp)))
1078
or tmpmax != (ifreq_flags)tmpmax){
1080
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1081
flagstring, if_entry->d_name);
1087
ifreq_flags flags = (ifreq_flags)tmpmax;
1088
/* Reject the loopback device */
1089
if(flags & IFF_LOOPBACK){
1091
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
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/* Accept point-to-point devices only if connect_to is specified */
1097
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1099
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1104
/* Otherwise, reject non-broadcast-capable devices */
1105
if(not (flags & IFF_BROADCAST)){
1107
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1112
/* Accept this device */
1114
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1120
978
int main(int argc, char *argv[]){
1121
979
AvahiSServiceBrowser *sb = NULL;
1124
982
intmax_t tmpmax;
1126
984
int exitcode = EXIT_SUCCESS;
1127
const char *interface = "";
985
const char *interface = "eth0";
1128
986
struct ifreq network;
1130
988
bool take_down_interface = false;
991
char *connect_to = NULL;
1133
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char tempdir[] = "/tmp/mandosXXXXXX";
1134
993
bool tempdir_created = false;
1135
994
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1293
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avahi_set_log_function(empty_log);
1296
if(interface[0] == '\0'){
1297
struct dirent **direntries;
1298
ret = scandir(sys_class_net, &direntries, good_interface,
1301
/* Pick the first good interface */
1302
interface = strdup(direntries[0]->d_name);
1304
fprintf(stderr, "Using interface \"%s\"\n", interface);
1306
if(interface == NULL){
1309
exitcode = EXIT_FAILURE;
1315
fprintf(stderr, "Could not find a network interface\n");
1316
exitcode = EXIT_FAILURE;
1321
1155
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1322
1156
from the signal handler */
1333
1167
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1335
1169
perror("sigaddset");
1336
exitcode = EX_OSERR;
1170
exitcode = EXIT_FAILURE;
1339
1173
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1341
1175
perror("sigaddset");
1342
exitcode = EX_OSERR;
1176
exitcode = EXIT_FAILURE;
1345
1179
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1347
1181
perror("sigaddset");
1348
exitcode = EX_OSERR;
1182
exitcode = EXIT_FAILURE;
1351
1185
/* Need to check if the handler is SIG_IGN before handling:
1355
1189
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1357
1191
perror("sigaction");
1192
return EXIT_FAILURE;
1360
1194
if(old_sigterm_action.sa_handler != SIG_IGN){
1361
1195
ret = sigaction(SIGINT, &sigterm_action, NULL);
1363
1197
perror("sigaction");
1364
exitcode = EX_OSERR;
1198
exitcode = EXIT_FAILURE;
1368
1202
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1370
1204
perror("sigaction");
1205
return EXIT_FAILURE;
1373
1207
if(old_sigterm_action.sa_handler != SIG_IGN){
1374
1208
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1376
1210
perror("sigaction");
1377
exitcode = EX_OSERR;
1211
exitcode = EXIT_FAILURE;
1381
1215
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1383
1217
perror("sigaction");
1218
return EXIT_FAILURE;
1386
1220
if(old_sigterm_action.sa_handler != SIG_IGN){
1387
1221
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1389
1223
perror("sigaction");
1390
exitcode = EX_OSERR;
1224
exitcode = EXIT_FAILURE;
1395
1229
/* If the interface is down, bring it up */
1396
if(strcmp(interface, "none") != 0){
1230
if(interface[0] != '\0'){
1397
1231
if_index = (AvahiIfIndex) if_nametoindex(interface);
1398
1232
if(if_index == 0){
1399
1233
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1400
exitcode = EX_UNAVAILABLE;
1234
exitcode = EXIT_FAILURE;
1470
1304
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1472
1306
take_down_interface = false;
1473
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1474
exitcode = EX_OSERR;
1307
perror("ioctl SIOCSIFFLAGS");
1308
exitcode = EXIT_FAILURE;
1475
1309
#ifdef __linux__
1476
1310
if(restore_loglevel){
1477
1311
ret = klogctl(7, NULL, 0);
1567
1401
if(not init_gpgme(pubkey, seckey, tempdir)){
1568
1402
fprintf(stderr, "init_gpgme failed\n");
1569
exitcode = EX_UNAVAILABLE;
1403
exitcode = EXIT_FAILURE;
1572
1406
gpgme_initialized = true;
1745
1561
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1746
1562
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1748
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1564
perror("ioctl SIOCSIFFLAGS");
1751
1567
ret = (int)TEMP_FAILURE_RETRY(close(sd));