199
148
* "buffer_length" is how much is already used.
201
150
size_t incbuffer(char **buffer, size_t buffer_length,
202
size_t buffer_capacity){
151
size_t buffer_capacity){
203
152
if(buffer_length + BUFFER_SIZE > buffer_capacity){
204
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
206
int old_errno = errno;
153
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
157
buffer_capacity += BUFFER_SIZE;
215
159
return buffer_capacity;
218
/* Add server to set of servers to retry periodically */
219
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
220
int af, server **current_server){
222
server *new_server = malloc(sizeof(server));
223
if(new_server == NULL){
224
perror_plus("malloc");
227
*new_server = (server){ .ip = strdup(ip),
229
.if_index = if_index,
231
if(new_server->ip == NULL){
232
perror_plus("strdup");
235
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
237
perror_plus("clock_gettime");
240
/* Special case of first server */
241
if(*current_server == NULL){
242
new_server->next = new_server;
243
new_server->prev = new_server;
244
*current_server = new_server;
245
/* Place the new server last in the list */
247
new_server->next = *current_server;
248
new_server->prev = (*current_server)->prev;
249
new_server->prev->next = new_server;
250
(*current_server)->prev = new_server;
256
163
* Initialize GPGME.
258
static bool init_gpgme(const char *seckey, const char *pubkey,
259
const char *tempdir, mandos_context *mc){
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
260
168
gpgme_error_t rc;
261
169
gpgme_engine_info_t engine_info;
264
173
* Helper function to insert pub and seckey to the engine keyring.
266
175
bool import_key(const char *filename){
269
177
gpgme_data_t pgp_data;
271
179
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
277
185
rc = gpgme_data_new_from_fd(&pgp_data, fd);
278
186
if(rc != GPG_ERR_NO_ERROR){
279
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
280
gpgme_strsource(rc), gpgme_strerror(rc));
187
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
284
rc = gpgme_op_import(mc->ctx, pgp_data);
192
rc = gpgme_op_import(mc.ctx, pgp_data);
285
193
if(rc != GPG_ERR_NO_ERROR){
286
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
287
gpgme_strsource(rc), gpgme_strerror(rc));
194
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
291
199
ret = (int)TEMP_FAILURE_RETRY(close(fd));
293
perror_plus("close");
295
203
gpgme_data_release(pgp_data);
300
fprintf_plus(stderr, "Initializing GPGME\n");
208
fprintf(stderr, "Initializing GPGME\n");
304
212
gpgme_check_version(NULL);
305
213
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
306
214
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
215
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
216
gpgme_strsource(rc), gpgme_strerror(rc));
312
/* Set GPGME home directory for the OpenPGP engine only */
220
/* Set GPGME home directory for the OpenPGP engine only */
313
221
rc = gpgme_get_engine_info(&engine_info);
314
222
if(rc != GPG_ERR_NO_ERROR){
315
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
316
gpgme_strsource(rc), gpgme_strerror(rc));
223
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
319
227
while(engine_info != NULL){
361
266
ssize_t plaintext_length = 0;
364
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
367
272
/* Create new GPGME data buffer from memory cryptotext */
368
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
370
275
if(rc != GPG_ERR_NO_ERROR){
371
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
372
gpgme_strsource(rc), gpgme_strerror(rc));
276
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
376
281
/* Create new empty GPGME data buffer for the plaintext */
377
282
rc = gpgme_data_new(&dh_plain);
378
283
if(rc != GPG_ERR_NO_ERROR){
379
fprintf_plus(stderr, "Mandos plugin mandos-client: "
380
"bad gpgme_data_new: %s: %s\n",
381
gpgme_strsource(rc), gpgme_strerror(rc));
284
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
382
286
gpgme_data_release(dh_crypto);
386
290
/* Decrypt data from the cryptotext data buffer to the plaintext
388
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
292
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
389
293
if(rc != GPG_ERR_NO_ERROR){
390
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
391
gpgme_strsource(rc), gpgme_strerror(rc));
294
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
295
gpgme_strsource(rc), gpgme_strerror(rc));
392
296
plaintext_length = -1;
394
298
gpgme_decrypt_result_t result;
395
result = gpgme_op_decrypt_result(mc->ctx);
299
result = gpgme_op_decrypt_result(mc.ctx);
396
300
if(result == NULL){
397
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
399
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
400
result->unsupported_algorithm);
401
fprintf_plus(stderr, "Wrong key usage: %u\n",
402
result->wrong_key_usage);
303
fprintf(stderr, "Unsupported algorithm: %s\n",
304
result->unsupported_algorithm);
305
fprintf(stderr, "Wrong key usage: %u\n",
306
result->wrong_key_usage);
403
307
if(result->file_name != NULL){
404
fprintf_plus(stderr, "File name: %s\n", result->file_name);
308
fprintf(stderr, "File name: %s\n", result->file_name);
406
310
gpgme_recipient_t recipient;
407
311
recipient = result->recipients;
408
while(recipient != NULL){
409
fprintf_plus(stderr, "Public key algorithm: %s\n",
410
gpgme_pubkey_algo_name
411
(recipient->pubkey_algo));
412
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
413
fprintf_plus(stderr, "Secret key available: %s\n",
414
recipient->status == GPG_ERR_NO_SECKEY
416
recipient = recipient->next;
313
while(recipient != NULL){
314
fprintf(stderr, "Public key algorithm: %s\n",
315
gpgme_pubkey_algo_name(recipient->pubkey_algo));
316
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
317
fprintf(stderr, "Secret key available: %s\n",
318
recipient->status == GPG_ERR_NO_SECKEY
320
recipient = recipient->next;
515
420
/* OpenPGP credentials */
516
ret = gnutls_certificate_allocate_credentials(&mc->cred);
421
gnutls_certificate_allocate_credentials(&mc.cred);
517
422
if(ret != GNUTLS_E_SUCCESS){
518
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
519
safer_gnutls_strerror(ret));
423
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
427
safer_gnutls_strerror(ret));
520
428
gnutls_global_deinit();
525
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
526
" secret key %s as GnuTLS credentials\n",
433
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
434
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
531
438
ret = gnutls_certificate_set_openpgp_key_file
532
(mc->cred, pubkeyfilename, seckeyfilename,
439
(mc.cred, pubkeyfilename, seckeyfilename,
533
440
GNUTLS_OPENPGP_FMT_BASE64);
534
441
if(ret != GNUTLS_E_SUCCESS){
536
"Error[%d] while reading the OpenPGP key pair ('%s',"
537
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
538
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
539
safer_gnutls_strerror(ret));
443
"Error[%d] while reading the OpenPGP key pair ('%s',"
444
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
445
fprintf(stderr, "The GnuTLS error is: %s\n",
446
safer_gnutls_strerror(ret));
543
450
/* GnuTLS server initialization */
544
ret = gnutls_dh_params_init(&mc->dh_params);
451
ret = gnutls_dh_params_init(&mc.dh_params);
545
452
if(ret != GNUTLS_E_SUCCESS){
546
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
547
" initialization: %s\n",
548
safer_gnutls_strerror(ret));
453
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
454
" %s\n", safer_gnutls_strerror(ret));
551
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
457
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
552
458
if(ret != GNUTLS_E_SUCCESS){
553
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
554
safer_gnutls_strerror(ret));
459
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
460
safer_gnutls_strerror(ret));
558
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
464
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
564
gnutls_certificate_free_credentials(mc->cred);
470
gnutls_certificate_free_credentials(mc.cred);
565
471
gnutls_global_deinit();
566
gnutls_dh_params_deinit(mc->dh_params);
472
gnutls_dh_params_deinit(mc.dh_params);
570
static int init_gnutls_session(gnutls_session_t *session,
476
static int init_gnutls_session(gnutls_session_t *session){
573
478
/* GnuTLS session creation */
575
ret = gnutls_init(session, GNUTLS_SERVER);
579
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
479
ret = gnutls_init(session, GNUTLS_SERVER);
580
480
if(ret != GNUTLS_E_SUCCESS){
582
"Error in GnuTLS session initialization: %s\n",
583
safer_gnutls_strerror(ret));
481
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
482
safer_gnutls_strerror(ret));
589
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
591
gnutls_deinit(*session);
594
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
487
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
595
488
if(ret != GNUTLS_E_SUCCESS){
596
fprintf_plus(stderr, "Syntax error at: %s\n", err);
597
fprintf_plus(stderr, "GnuTLS error: %s\n",
598
safer_gnutls_strerror(ret));
489
fprintf(stderr, "Syntax error at: %s\n", err);
490
fprintf(stderr, "GnuTLS error: %s\n",
491
safer_gnutls_strerror(ret));
599
492
gnutls_deinit(*session);
605
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
608
gnutls_deinit(*session);
611
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
497
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
612
499
if(ret != GNUTLS_E_SUCCESS){
613
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
614
safer_gnutls_strerror(ret));
500
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
501
safer_gnutls_strerror(ret));
615
502
gnutls_deinit(*session);
619
506
/* ignore client certificate if any. */
620
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
507
gnutls_certificate_server_set_request(*session,
622
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
510
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
731
573
ret = inet_pton(af, ip, &to.in.sin_addr);
735
perror_plus("inet_pton");
741
fprintf_plus(stderr, "Bad address: %s\n", ip);
580
fprintf(stderr, "Bad address: %s\n", ip);
745
583
if(af == AF_INET6){
746
to.in6.sin6_port = htons(port);
748
#pragma GCC diagnostic push
749
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
584
to.in6.sin6_port = htons(port); /* Spurious warnings from
586
-Wunreachable-code */
751
588
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
752
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */
754
#pragma GCC diagnostic pop
589
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
756
591
if(if_index == AVAHI_IF_UNSPEC){
757
fprintf_plus(stderr, "An IPv6 link-local address is"
758
" incomplete without a network interface\n");
592
fprintf(stderr, "An IPv6 link-local address is incomplete"
593
" without a network interface\n");
762
596
/* Set the network interface number as scope */
763
597
to.in6.sin6_scope_id = (uint32_t)if_index;
766
to.in.sin_port = htons(port);
600
to.in.sin_port = htons(port); /* Spurious warnings from
602
-Wunreachable-code */
775
606
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
776
607
char interface[IF_NAMESIZE];
777
608
if(if_indextoname((unsigned int)if_index, interface) == NULL){
778
perror_plus("if_indextoname");
609
perror("if_indextoname");
780
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
781
"\n", ip, interface, (uintmax_t)port);
611
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
612
ip, interface, port);
784
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
785
ip, (uintmax_t)port);
615
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
787
618
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
788
619
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
789
621
if(af == AF_INET6){
790
ret = getnameinfo((struct sockaddr *)&(to.in6), sizeof(to.in6),
791
addrstr, sizeof(addrstr), NULL, 0,
794
ret = getnameinfo((struct sockaddr *)&(to.in), sizeof(to.in),
795
addrstr, sizeof(addrstr), NULL, 0,
798
if(ret == EAI_SYSTEM){
799
perror_plus("getnameinfo");
800
} else if(ret != 0) {
801
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
802
} else if(strcmp(addrstr, ip) != 0){
803
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
622
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
625
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
631
if(strcmp(addrstr, ip) != 0){
632
fprintf(stderr, "Canonical address form: %s\n", addrstr);
812
637
if(af == AF_INET6){
1152
871
case AVAHI_BROWSER_ALL_FOR_NOW:
1153
872
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1155
fprintf_plus(stderr, "No Mandos server found, still"
874
fprintf(stderr, "No Mandos server found, still searching...\n");
1162
/* Signal handler that stops main loop after SIGTERM */
1163
static void handle_sigterm(int sig){
880
sig_atomic_t quit_now = 0;
882
/* stop main loop after sigterm has been called */
883
static void handle_sigterm(__attribute__((unused)) int sig){
1168
signal_received = sig;
1169
888
int old_errno = errno;
1170
/* set main loop to exit */
1171
if(simple_poll != NULL){
1172
avahi_simple_poll_quit(simple_poll);
1177
bool get_flags(const char *ifname, struct ifreq *ifr){
1181
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1184
perror_plus("socket");
1188
strcpy(ifr->ifr_name, ifname);
1189
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1193
perror_plus("ioctl SIOCGIFFLAGS");
1201
bool good_flags(const char *ifname, const struct ifreq *ifr){
1203
/* Reject the loopback device */
1204
if(ifr->ifr_flags & IFF_LOOPBACK){
1206
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1211
/* Accept point-to-point devices only if connect_to is specified */
1212
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1214
fprintf_plus(stderr, "Accepting point-to-point interface"
1215
" \"%s\"\n", ifname);
1219
/* Otherwise, reject non-broadcast-capable devices */
1220
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1222
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1223
" \"%s\"\n", ifname);
1227
/* Reject non-ARP interfaces (including dummy interfaces) */
1228
if(ifr->ifr_flags & IFF_NOARP){
1230
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1236
/* Accept this device */
1238
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1244
* This function determines if a directory entry in /sys/class/net
1245
* corresponds to an acceptable network device.
1246
* (This function is passed to scandir(3) as a filter function.)
1248
int good_interface(const struct dirent *if_entry){
1249
if(if_entry->d_name[0] == '.'){
1254
if(not get_flags(if_entry->d_name, &ifr)){
1256
fprintf_plus(stderr, "Failed to get flags for interface "
1257
"\"%s\"\n", if_entry->d_name);
1262
if(not good_flags(if_entry->d_name, &ifr)){
1269
* This function determines if a network interface is up.
1271
bool interface_is_up(const char *interface){
1273
if(not get_flags(interface, &ifr)){
1275
fprintf_plus(stderr, "Failed to get flags for interface "
1276
"\"%s\"\n", interface);
1281
return (bool)(ifr.ifr_flags & IFF_UP);
1285
* This function determines if a network interface is running
1287
bool interface_is_running(const char *interface){
1289
if(not get_flags(interface, &ifr)){
1291
fprintf_plus(stderr, "Failed to get flags for interface "
1292
"\"%s\"\n", interface);
1297
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1300
int notdotentries(const struct dirent *direntry){
1301
/* Skip "." and ".." */
1302
if(direntry->d_name[0] == '.'
1303
and (direntry->d_name[1] == '\0'
1304
or (direntry->d_name[1] == '.'
1305
and direntry->d_name[2] == '\0'))){
1311
/* Is this directory entry a runnable program? */
1312
int runnable_hook(const struct dirent *direntry){
1317
if((direntry->d_name)[0] == '\0'){
1322
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1323
"abcdefghijklmnopqrstuvwxyz"
1326
if((direntry->d_name)[sret] != '\0'){
1327
/* Contains non-allowed characters */
1329
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1335
char *fullname = NULL;
1336
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1338
perror_plus("asprintf");
1342
ret = stat(fullname, &st);
1345
perror_plus("Could not stat hook");
1349
if(not (S_ISREG(st.st_mode))){
1350
/* Not a regular file */
1352
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1357
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1358
/* Not executable */
1360
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1366
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1372
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1373
mandos_context *mc){
1375
struct timespec now;
1376
struct timespec waited_time;
1377
intmax_t block_time;
1380
if(mc->current_server == NULL){
1382
fprintf_plus(stderr, "Wait until first server is found."
1385
ret = avahi_simple_poll_iterate(s, -1);
1388
fprintf_plus(stderr, "Check current_server if we should run"
1391
/* the current time */
1392
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1394
perror_plus("clock_gettime");
1397
/* Calculating in ms how long time between now and server
1398
who we visted longest time ago. Now - last seen. */
1399
waited_time.tv_sec = (now.tv_sec
1400
- mc->current_server->last_seen.tv_sec);
1401
waited_time.tv_nsec = (now.tv_nsec
1402
- mc->current_server->last_seen.tv_nsec);
1403
/* total time is 10s/10,000ms.
1404
Converting to s from ms by dividing by 1,000,
1405
and ns to ms by dividing by 1,000,000. */
1406
block_time = ((retry_interval
1407
- ((intmax_t)waited_time.tv_sec * 1000))
1408
- ((intmax_t)waited_time.tv_nsec / 1000000));
1411
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1415
if(block_time <= 0){
1416
ret = start_mandos_communication(mc->current_server->ip,
1417
mc->current_server->port,
1418
mc->current_server->if_index,
1419
mc->current_server->af, mc);
1421
avahi_simple_poll_quit(s);
1424
ret = clock_gettime(CLOCK_MONOTONIC,
1425
&mc->current_server->last_seen);
1427
perror_plus("clock_gettime");
1430
mc->current_server = mc->current_server->next;
1431
block_time = 0; /* Call avahi to find new Mandos
1432
servers, but don't block */
1435
ret = avahi_simple_poll_iterate(s, (int)block_time);
1438
if (ret > 0 or errno != EINTR){
1439
return (ret != 1) ? ret : 0;
1445
/* Set effective uid to 0, return errno */
1446
error_t raise_privileges(void){
1447
error_t old_errno = errno;
1448
error_t ret_errno = 0;
1449
if(seteuid(0) == -1){
1451
perror_plus("seteuid");
1457
/* Set effective and real user ID to 0. Return errno. */
1458
error_t raise_privileges_permanently(void){
1459
error_t old_errno = errno;
1460
error_t ret_errno = raise_privileges();
1465
if(setuid(0) == -1){
1467
perror_plus("seteuid");
1473
/* Set effective user ID to unprivileged saved user ID */
1474
error_t lower_privileges(void){
1475
error_t old_errno = errno;
1476
error_t ret_errno = 0;
1477
if(seteuid(uid) == -1){
1479
perror_plus("seteuid");
1485
/* Lower privileges permanently */
1486
error_t lower_privileges_permanently(void){
1487
error_t old_errno = errno;
1488
error_t ret_errno = 0;
1489
if(setuid(uid) == -1){
1491
perror_plus("setuid");
1497
bool run_network_hooks(const char *mode, const char *interface,
1499
struct dirent **direntries;
1500
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1503
if(errno == ENOENT){
1505
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1506
" found\n", hookdir);
1509
perror_plus("scandir");
1512
struct dirent *direntry;
1514
int devnull = open("/dev/null", O_RDONLY);
1515
for(int i = 0; i < numhooks; i++){
1516
direntry = direntries[i];
1517
char *fullname = NULL;
1518
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1520
perror_plus("asprintf");
1524
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1527
pid_t hook_pid = fork();
1530
/* Raise privileges */
1531
raise_privileges_permanently();
1536
perror_plus("setgid");
1538
/* Reset supplementary groups */
1540
ret = setgroups(0, NULL);
1542
perror_plus("setgroups");
1544
dup2(devnull, STDIN_FILENO);
1546
dup2(STDERR_FILENO, STDOUT_FILENO);
1547
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1549
perror_plus("setenv");
1552
ret = setenv("DEVICE", interface, 1);
1554
perror_plus("setenv");
1557
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1559
perror_plus("setenv");
1562
ret = setenv("MODE", mode, 1);
1564
perror_plus("setenv");
1568
ret = asprintf(&delaystring, "%f", delay);
1570
perror_plus("asprintf");
1573
ret = setenv("DELAY", delaystring, 1);
1576
perror_plus("setenv");
1580
if(connect_to != NULL){
1581
ret = setenv("CONNECT", connect_to, 1);
1583
perror_plus("setenv");
1587
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1588
perror_plus("execl");
1589
_exit(EXIT_FAILURE);
1593
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1594
perror_plus("waitpid");
1598
if(WIFEXITED(status)){
1599
if(WEXITSTATUS(status) != 0){
1600
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1601
" with status %d\n", direntry->d_name,
1602
WEXITSTATUS(status));
1606
} else if(WIFSIGNALED(status)){
1607
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1608
" signal %d\n", direntry->d_name,
1613
fprintf_plus(stderr, "Warning: network hook \"%s\""
1614
" crashed\n", direntry->d_name);
1621
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1630
error_t bring_up_interface(const char *const interface,
1633
error_t old_errno = errno;
1634
error_t ret_errno = 0;
1635
int ret, ret_setflags;
1636
struct ifreq network;
1637
unsigned int if_index = if_nametoindex(interface);
1639
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1649
if(not interface_is_up(interface)){
1650
if(not get_flags(interface, &network) and debug){
1652
fprintf_plus(stderr, "Failed to get flags for interface "
1653
"\"%s\"\n", interface);
1656
network.ifr_flags |= IFF_UP;
1658
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1661
perror_plus("socket");
1673
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1677
/* Raise priviliges */
1681
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1682
messages about the network interface to mess up the prompt */
1683
int ret_linux = klogctl(8, NULL, 5);
1684
bool restore_loglevel = true;
1685
if(ret_linux == -1){
1686
restore_loglevel = false;
1687
perror_plus("klogctl");
1689
#endif /* __linux__ */
1690
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1693
if(restore_loglevel){
1694
ret_linux = klogctl(7, NULL, 0);
1695
if(ret_linux == -1){
1696
perror_plus("klogctl");
1699
#endif /* __linux__ */
1701
/* Lower privileges */
1704
/* Close the socket */
1705
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1707
perror_plus("close");
1710
if(ret_setflags == -1){
1712
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1717
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1721
/* Sleep checking until interface is running.
1722
Check every 0.25s, up to total time of delay */
1723
for(int i=0; i < delay * 4; i++){
1724
if(interface_is_running(interface)){
1727
struct timespec sleeptime = { .tv_nsec = 250000000 };
1728
ret = nanosleep(&sleeptime, NULL);
1729
if(ret == -1 and errno != EINTR){
1730
perror_plus("nanosleep");
1738
error_t take_down_interface(const char *const interface){
1739
error_t old_errno = errno;
1740
struct ifreq network;
1741
unsigned int if_index = if_nametoindex(interface);
1743
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1747
if(interface_is_up(interface)){
1748
error_t ret_errno = 0;
1749
if(not get_flags(interface, &network) and debug){
1751
fprintf_plus(stderr, "Failed to get flags for interface "
1752
"\"%s\"\n", interface);
1755
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1757
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1760
perror_plus("socket");
1766
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1770
/* Raise priviliges */
1773
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1776
/* Lower privileges */
1779
/* Close the socket */
1780
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1782
perror_plus("close");
1785
if(ret_setflags == -1){
1787
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1792
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
889
if(mc.simple_poll != NULL){
890
avahi_simple_poll_quit(mc.simple_poll);
1800
895
int main(int argc, char *argv[]){
1801
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1802
.priority = "SECURE256:!CTYPE-X.509:"
1803
"+CTYPE-OPENPGP", .current_server = NULL,
1804
.interfaces = NULL, .interfaces_size = 0 };
1805
896
AvahiSServiceBrowser *sb = NULL;
1808
899
intmax_t tmpmax;
1810
901
int exitcode = EXIT_SUCCESS;
1811
char *interfaces_to_take_down = NULL;
1812
size_t interfaces_to_take_down_size = 0;
902
const char *interface = "eth0";
903
struct ifreq network;
907
char *connect_to = NULL;
1813
908
char tempdir[] = "/tmp/mandosXXXXXX";
1814
909
bool tempdir_created = false;
1815
910
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1816
911
const char *seckey = PATHDIR "/" SECKEY;
1817
912
const char *pubkey = PATHDIR "/" PUBKEY;
1818
char *interfaces_hooks = NULL;
1820
914
bool gnutls_initialized = false;
1821
915
bool gpgme_initialized = false;
1822
916
float delay = 2.5f;
1823
double retry_interval = 10; /* 10s between trying a server and
1824
retrying the same server again */
1826
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
918
struct sigaction old_sigterm_action;
1827
919
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1832
/* Lower any group privileges we might have, just to be safe */
1836
perror_plus("setgid");
1839
/* Lower user privileges (temporarily) */
1843
perror_plus("seteuid");
1851
922
struct argp_option options[] = {
1852
923
{ .name = "debug", .key = 128,
1941
991
delay = strtof(arg, &tmp);
1942
992
if(errno != 0 or tmp == arg or *tmp != '\0'){
1943
argp_error(state, "Bad delay");
1945
case 132: /* --retry */
1947
retry_interval = strtod(arg, &tmp);
1948
if(errno != 0 or tmp == arg or *tmp != '\0'
1949
or (retry_interval * 1000) > INT_MAX
1950
or retry_interval < 0){
1951
argp_error(state, "Bad retry interval");
1954
case 133: /* --network-hook-dir */
1958
* These reproduce what we would get without ARGP_NO_HELP
1960
case '?': /* --help */
1961
argp_state_help(state, state->out_stream,
1962
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1963
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1964
case -3: /* --usage */
1965
argp_state_help(state, state->out_stream,
1966
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1967
case 'V': /* --version */
1968
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1969
exit(argp_err_exit_status);
993
fprintf(stderr, "Bad delay\n");
1972
1002
return ARGP_ERR_UNKNOWN;
1977
1007
struct argp argp = { .options = options, .parser = parse_opt,
1978
1008
.args_doc = "",
1979
1009
.doc = "Mandos client -- Get and decrypt"
1980
1010
" passwords from a Mandos server" };
1981
ret = argp_parse(&argp, argc, argv,
1982
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1989
perror_plus("argp_parse");
1990
exitcode = EX_OSERR;
1993
exitcode = EX_USAGE;
1999
/* Work around Debian bug #633582:
2000
<http://bugs.debian.org/633582> */
2002
/* Re-raise priviliges */
2003
if(raise_privileges() == 0){
2006
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2007
int seckey_fd = open(seckey, O_RDONLY);
2008
if(seckey_fd == -1){
2009
perror_plus("open");
2011
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2013
perror_plus("fstat");
2015
if(S_ISREG(st.st_mode)
2016
and st.st_uid == 0 and st.st_gid == 0){
2017
ret = fchown(seckey_fd, uid, gid);
2019
perror_plus("fchown");
2023
TEMP_FAILURE_RETRY(close(seckey_fd));
2027
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2028
int pubkey_fd = open(pubkey, O_RDONLY);
2029
if(pubkey_fd == -1){
2030
perror_plus("open");
2032
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2034
perror_plus("fstat");
2036
if(S_ISREG(st.st_mode)
2037
and st.st_uid == 0 and st.st_gid == 0){
2038
ret = fchown(pubkey_fd, uid, gid);
2040
perror_plus("fchown");
2044
TEMP_FAILURE_RETRY(close(pubkey_fd));
2048
/* Lower privileges */
2053
/* Remove invalid interface names (except "none") */
2055
char *interface = NULL;
2056
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2058
if(strcmp(interface, "none") != 0
2059
and if_nametoindex(interface) == 0){
2060
if(interface[0] != '\0'){
2061
fprintf_plus(stderr, "Not using nonexisting interface"
2062
" \"%s\"\n", interface);
2064
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2070
/* Run network hooks */
2072
if(mc.interfaces != NULL){
2073
interfaces_hooks = malloc(mc.interfaces_size);
2074
if(interfaces_hooks == NULL){
2075
perror_plus("malloc");
2078
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2079
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2081
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2082
interfaces_hooks : "", delay)){
1011
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1012
if(ret == ARGP_ERR_UNKNOWN){
1013
fprintf(stderr, "Unknown error while parsing arguments\n");
1014
exitcode = EXIT_FAILURE;
2092
1024
from the signal handler */
2093
1025
/* Initialize the pseudo-RNG for Avahi */
2094
1026
srand((unsigned int) time(NULL));
2095
simple_poll = avahi_simple_poll_new();
2096
if(simple_poll == NULL){
2097
fprintf_plus(stderr,
2098
"Avahi: Failed to create simple poll object.\n");
2099
exitcode = EX_UNAVAILABLE;
1027
mc.simple_poll = avahi_simple_poll_new();
1028
if(mc.simple_poll == NULL){
1029
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1030
exitcode = EXIT_FAILURE;
2103
1034
sigemptyset(&sigterm_action.sa_mask);
2104
1035
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2106
perror_plus("sigaddset");
2107
exitcode = EX_OSERR;
1037
perror("sigaddset");
1038
exitcode = EXIT_FAILURE;
2110
1041
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2112
perror_plus("sigaddset");
2113
exitcode = EX_OSERR;
1043
perror("sigaddset");
1044
exitcode = EXIT_FAILURE;
2116
1047
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2118
perror_plus("sigaddset");
2119
exitcode = EX_OSERR;
2122
/* Need to check if the handler is SIG_IGN before handling:
2123
| [[info:libc:Initial Signal Actions]] |
2124
| [[info:libc:Basic Signal Handling]] |
2126
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2128
perror_plus("sigaction");
2131
if(old_sigterm_action.sa_handler != SIG_IGN){
2132
ret = sigaction(SIGINT, &sigterm_action, NULL);
2134
perror_plus("sigaction");
2135
exitcode = EX_OSERR;
2139
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2141
perror_plus("sigaction");
2144
if(old_sigterm_action.sa_handler != SIG_IGN){
2145
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2147
perror_plus("sigaction");
2148
exitcode = EX_OSERR;
2152
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2154
perror_plus("sigaction");
2157
if(old_sigterm_action.sa_handler != SIG_IGN){
2158
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2160
perror_plus("sigaction");
2161
exitcode = EX_OSERR;
2166
/* If no interfaces were specified, make a list */
2167
if(mc.interfaces == NULL){
2168
struct dirent **direntries;
2169
/* Look for any good interfaces */
2170
ret = scandir(sys_class_net, &direntries, good_interface,
2173
/* Add all found interfaces to interfaces list */
2174
for(int i = 0; i < ret; ++i){
2175
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2176
direntries[i]->d_name);
2179
perror_plus("argz_add");
2183
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2184
direntries[i]->d_name);
2190
fprintf_plus(stderr, "Could not find a network interface\n");
2191
exitcode = EXIT_FAILURE;
2196
/* Bring up interfaces which are down, and remove any "none"s */
2198
char *interface = NULL;
2199
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2201
/* If interface name is "none", stop bringing up interfaces.
2202
Also remove all instances of "none" from the list */
2203
if(strcmp(interface, "none") == 0){
2204
argz_delete(&mc.interfaces, &mc.interfaces_size,
2207
while((interface = argz_next(mc.interfaces,
2208
mc.interfaces_size, interface))){
2209
if(strcmp(interface, "none") == 0){
2210
argz_delete(&mc.interfaces, &mc.interfaces_size,
1049
perror("sigaddset");
1050
exitcode = EXIT_FAILURE;
1053
ret = sigaction(SIGTERM, &sigterm_action, &old_sigterm_action);
1055
perror("sigaction");
1056
exitcode = EXIT_FAILURE;
1060
/* If the interface is down, bring it up */
1061
if(interface[0] != '\0'){
1063
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1064
messages to mess up the prompt */
1065
ret = klogctl(8, NULL, 5);
1066
bool restore_loglevel = true;
1068
restore_loglevel = false;
1071
#endif /* __linux__ */
1073
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1076
exitcode = EXIT_FAILURE;
1078
if(restore_loglevel){
1079
ret = klogctl(7, NULL, 0);
1084
#endif /* __linux__ */
1087
strcpy(network.ifr_name, interface);
1088
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1090
perror("ioctl SIOCGIFFLAGS");
1092
if(restore_loglevel){
1093
ret = klogctl(7, NULL, 0);
1098
#endif /* __linux__ */
1099
exitcode = EXIT_FAILURE;
1102
if((network.ifr_flags & IFF_UP) == 0){
1103
network.ifr_flags |= IFF_UP;
1104
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1106
perror("ioctl SIOCSIFFLAGS");
1107
exitcode = EXIT_FAILURE;
1109
if(restore_loglevel){
1110
ret = klogctl(7, NULL, 0);
1115
#endif /* __linux__ */
1119
/* sleep checking until interface is running */
1120
for(int i=0; i < delay * 4; i++){
1121
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1123
perror("ioctl SIOCGIFFLAGS");
1124
} else if(network.ifr_flags & IFF_RUNNING){
2217
bool interface_was_up = interface_is_up(interface);
2218
ret = bring_up_interface(interface, delay);
2219
if(not interface_was_up){
2222
perror_plus("Failed to bring up interface");
2224
ret_errno = argz_add(&interfaces_to_take_down,
2225
&interfaces_to_take_down_size,
2229
perror_plus("argz_add");
2234
if(debug and (interfaces_to_take_down == NULL)){
2235
fprintf_plus(stderr, "No interfaces were brought up\n");
2239
/* If we only got one interface, explicitly use only that one */
2240
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2242
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2245
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2252
ret = init_gnutls_global(pubkey, seckey, &mc);
2254
fprintf_plus(stderr, "init_gnutls_global failed\n");
2255
exitcode = EX_UNAVAILABLE;
1127
struct timespec sleeptime = { .tv_nsec = 250000000 };
1128
ret = nanosleep(&sleeptime, NULL);
1129
if(ret == -1 and errno != EINTR){
1130
perror("nanosleep");
1133
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1138
if(restore_loglevel){
1139
/* Restores kernel loglevel to default */
1140
ret = klogctl(7, NULL, 0);
1145
#endif /* __linux__ */
1162
ret = init_gnutls_global(pubkey, seckey);
1164
fprintf(stderr, "init_gnutls_global failed\n");
1165
exitcode = EXIT_FAILURE;
2258
1168
gnutls_initialized = true;
2265
1171
if(mkdtemp(tempdir) == NULL){
2266
perror_plus("mkdtemp");
2269
1175
tempdir_created = true;
2275
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2276
fprintf_plus(stderr, "init_gpgme failed\n");
2277
exitcode = EX_UNAVAILABLE;
1177
if(not init_gpgme(pubkey, seckey, tempdir)){
1178
fprintf(stderr, "init_gpgme failed\n");
1179
exitcode = EXIT_FAILURE;
2280
1182
gpgme_initialized = true;
1185
if(interface[0] != '\0'){
1186
if_index = (AvahiIfIndex) if_nametoindex(interface);
1188
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1189
exitcode = EXIT_FAILURE;
2287
1194
if(connect_to != NULL){
2288
1195
/* Connect directly, do not use Zeroconf */
2289
1196
/* (Mainly meant for debugging) */
2290
1197
char *address = strrchr(connect_to, ':');
2292
1198
if(address == NULL){
2293
fprintf_plus(stderr, "No colon in address\n");
2294
exitcode = EX_USAGE;
1199
fprintf(stderr, "No colon in address\n");
1200
exitcode = EXIT_FAILURE;
2304
1205
tmpmax = strtoimax(address+1, &tmp, 10);
2305
1206
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2306
or tmpmax != (in_port_t)tmpmax){
2307
fprintf_plus(stderr, "Bad port number\n");
2308
exitcode = EX_USAGE;
2316
port = (in_port_t)tmpmax;
1207
or tmpmax != (uint16_t)tmpmax){
1208
fprintf(stderr, "Bad port number\n");
1209
exitcode = EXIT_FAILURE;
1212
port = (uint16_t)tmpmax;
2317
1213
*address = '\0';
1214
address = connect_to;
2318
1215
/* Colon in address indicates IPv6 */
2320
if(strchr(connect_to, ':') != NULL){
1217
if(strchr(address, ':') != NULL){
2322
/* Accept [] around IPv6 address - see RFC 5952 */
2323
if(connect_to[0] == '[' and address[-1] == ']')
2331
address = connect_to;
2337
while(not quit_now){
2338
ret = start_mandos_communication(address, port, if_index, af,
2340
if(quit_now or ret == 0){
2344
fprintf_plus(stderr, "Retrying in %d seconds\n",
2345
(int)retry_interval);
2347
sleep((unsigned int)retry_interval);
1222
ret = start_mandos_communication(address, port, if_index, af);
1224
exitcode = EXIT_FAILURE;
2351
1226
exitcode = EXIT_SUCCESS;
2362
1232
AvahiServerConfig config;
2363
1233
/* Do not publish any local Zeroconf records */