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() */
73
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
74
getuid(), getgid(), seteuid(),
76
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
77
#include <iso646.h> /* not, or, and */
78
78
#include <argp.h> /* struct argp_option, error_t, struct
82
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
83
sigaction(), SIGTERM, sig_atomic_t,
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
87
#include <sys/klog.h> /* klogctl() */
127
125
static const char mandos_protocol_version[] = "1";
128
126
const char *argp_program_version = "mandos-client " VERSION;
129
127
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;
133
129
/* Used for passing in values through the Avahi callback functions */
807
793
ret = gnutls_handshake(session);
813
799
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
815
801
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
816
802
gnutls_perror(ret);
822
808
fprintf(stderr, "Unknown error while reading data from"
823
809
" encrypted session with Mandos server\n");
824
811
gnutls_bye(session, GNUTLS_SHUT_RDWR);
865
851
(size_t)decrypted_buffer_size - written,
867
853
if(ret == 0 and ferror(stdout)){
870
855
fprintf(stderr, "Error writing encrypted data: %s\n",
871
856
strerror(errno));
876
861
written += (size_t)ret;
863
free(decrypted_buffer);
882
871
/* Shutdown procedure */
887
free(decrypted_buffer);
890
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
898
gnutls_deinit(session);
876
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
881
gnutls_deinit(session);
1022
1002
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;
1033
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",
1096
/* 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
1005
int main(int argc, char *argv[]){
1121
1006
AvahiSServiceBrowser *sb = NULL;
1124
1009
intmax_t tmpmax;
1126
1011
int exitcode = EXIT_SUCCESS;
1127
const char *interface = "";
1012
const char *interface = "eth0";
1128
1013
struct ifreq network;
1130
1015
bool take_down_interface = false;
1018
char *connect_to = NULL;
1133
1019
char tempdir[] = "/tmp/mandosXXXXXX";
1134
1020
bool tempdir_created = false;
1135
1021
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1198
1084
.arg = "SECONDS",
1199
1085
.doc = "Maximum delay to wait for interface startup",
1202
* These reproduce what we would get without ARGP_NO_HELP
1204
{ .name = "help", .key = '?',
1205
.doc = "Give this help list", .group = -1 },
1206
{ .name = "usage", .key = -3,
1207
.doc = "Give a short usage message", .group = -1 },
1208
{ .name = "version", .key = 'V',
1209
.doc = "Print program version", .group = -1 },
1210
1087
{ .name = NULL }
1213
1090
error_t parse_opt(int key, char *arg,
1214
1091
struct argp_state *state){
1217
1093
case 128: /* --debug */
1234
1110
tmpmax = strtoimax(arg, &tmp, 10);
1235
1111
if(errno != 0 or tmp == arg or *tmp != '\0'
1236
1112
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1237
argp_error(state, "Bad number of DH bits");
1113
fprintf(stderr, "Bad number of DH bits\n");
1239
1116
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1246
1123
delay = strtof(arg, &tmp);
1247
1124
if(errno != 0 or tmp == arg or *tmp != '\0'){
1248
argp_error(state, "Bad delay");
1125
fprintf(stderr, "Bad delay\n");
1252
* These reproduce what we would get without ARGP_NO_HELP
1254
case '?': /* --help */
1255
argp_state_help(state, state->out_stream,
1256
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1257
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1258
case -3: /* --usage */
1259
argp_state_help(state, state->out_stream,
1260
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1261
case 'V': /* --version */
1262
fprintf(state->out_stream, "%s\n", argp_program_version);
1263
exit(argp_err_exit_status);
1266
1134
return ARGP_ERR_UNKNOWN;
1271
1139
struct argp argp = { .options = options, .parser = parse_opt,
1272
1140
.args_doc = "",
1273
1141
.doc = "Mandos client -- Get and decrypt"
1274
1142
" passwords from a Mandos server" };
1275
ret = argp_parse(&argp, argc, argv,
1276
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1283
perror("argp_parse");
1284
exitcode = EX_OSERR;
1287
exitcode = EX_USAGE;
1143
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1144
if(ret == ARGP_ERR_UNKNOWN){
1145
fprintf(stderr, "Unknown error while parsing arguments\n");
1146
exitcode = EXIT_FAILURE;
1293
1152
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;
1415
1249
#ifdef __linux__
1416
1250
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1417
messages about the network interface to mess up the prompt */
1251
messages to mess up the prompt */
1418
1252
ret = klogctl(8, NULL, 5);
1419
1253
bool restore_loglevel = true;
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;
1743
1559
perror("ioctl SIOCGIFFLAGS");
1744
1560
} else if(network.ifr_flags & IFF_UP) {
1745
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1561
network.ifr_flags &= ~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));
1809
1625
sigemptyset(&old_sigterm_action.sa_mask);
1810
1626
old_sigterm_action.sa_handler = SIG_DFL;
1811
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
1812
&old_sigterm_action,
1627
ret = sigaction(signal_received, &old_sigterm_action, NULL);
1815
1629
perror("sigaction");
1818
ret = raise(signal_received);
1819
} while(ret != 0 and errno == EINTR);
1824
TEMP_FAILURE_RETRY(pause());
1631
raise(signal_received);
1827
1634
return exitcode;