249
217
if(new_server->ip == NULL){
250
218
perror_plus("strdup");
254
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
256
perror_plus("clock_gettime");
258
#pragma GCC diagnostic push
259
#pragma GCC diagnostic ignored "-Wcast-qual"
261
free((char *)(new_server->ip));
263
#pragma GCC diagnostic pop
268
221
/* Special case of first server */
269
if(*current_server == NULL){
222
if (mc.current_server == NULL){
270
223
new_server->next = new_server;
271
224
new_server->prev = new_server;
272
*current_server = new_server;
225
mc.current_server = new_server;
226
/* Place the new server last in the list */
274
/* Place the new server last in the list */
275
new_server->next = *current_server;
276
new_server->prev = (*current_server)->prev;
228
new_server->next = mc.current_server;
229
new_server->prev = mc.current_server->prev;
277
230
new_server->prev->next = new_server;
278
(*current_server)->prev = new_server;
283
/* Set effective uid to 0, return errno */
284
__attribute__((warn_unused_result))
285
int raise_privileges(void){
286
int old_errno = errno;
288
if(seteuid(0) == -1){
295
/* Set effective and real user ID to 0. Return errno. */
296
__attribute__((warn_unused_result))
297
int raise_privileges_permanently(void){
298
int old_errno = errno;
299
int ret = raise_privileges();
311
/* Set effective user ID to unprivileged saved user ID */
312
__attribute__((warn_unused_result))
313
int lower_privileges(void){
314
int old_errno = errno;
316
if(seteuid(uid) == -1){
323
/* Lower privileges permanently */
324
__attribute__((warn_unused_result))
325
int lower_privileges_permanently(void){
326
int old_errno = errno;
328
if(setuid(uid) == -1){
231
mc.current_server->prev = new_server;
233
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
235
perror_plus("clock_gettime");
336
242
* Initialize GPGME.
338
__attribute__((nonnull, warn_unused_result))
339
static bool init_gpgme(const char * const seckey,
340
const char * const pubkey,
341
const char * const tempdir,
244
static bool init_gpgme(const char *seckey, const char *pubkey,
245
const char *tempdir){
343
246
gpgme_error_t rc;
344
247
gpgme_engine_info_t engine_info;
347
251
* Helper function to insert pub and seckey to the engine keyring.
349
bool import_key(const char * const filename){
253
bool import_key(const char *filename){
352
256
gpgme_data_t pgp_data;
416
rc = gpgme_op_import(mc->ctx, pgp_data);
271
rc = gpgme_op_import(mc.ctx, pgp_data);
417
272
if(rc != GPG_ERR_NO_ERROR){
418
273
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
419
274
gpgme_strsource(rc), gpgme_strerror(rc));
423
gpgme_import_result_t import_result
424
= gpgme_op_import_result(mc->ctx);
425
if((import_result->imported < 1
426
or import_result->not_imported > 0)
427
and import_result->unchanged == 0){
428
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
430
"The total number of considered keys: %d\n",
431
import_result->considered);
433
"The number of keys without user ID: %d\n",
434
import_result->no_user_id);
436
"The total number of imported keys: %d\n",
437
import_result->imported);
438
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
439
import_result->imported_rsa);
440
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
441
import_result->unchanged);
442
fprintf_plus(stderr, "The number of new user IDs: %d\n",
443
import_result->new_user_ids);
444
fprintf_plus(stderr, "The number of new sub keys: %d\n",
445
import_result->new_sub_keys);
446
fprintf_plus(stderr, "The number of new signatures: %d\n",
447
import_result->new_signatures);
448
fprintf_plus(stderr, "The number of new revocations: %d\n",
449
import_result->new_revocations);
451
"The total number of secret keys read: %d\n",
452
import_result->secret_read);
454
"The number of imported secret keys: %d\n",
455
import_result->secret_imported);
457
"The number of unchanged secret keys: %d\n",
458
import_result->secret_unchanged);
459
fprintf_plus(stderr, "The number of keys not imported: %d\n",
460
import_result->not_imported);
461
for(gpgme_import_status_t import_status
462
= import_result->imports;
463
import_status != NULL;
464
import_status = import_status->next){
465
fprintf_plus(stderr, "Import status for key: %s\n",
467
if(import_status->result != GPG_ERR_NO_ERROR){
468
fprintf_plus(stderr, "Import result: %s: %s\n",
469
gpgme_strsource(import_status->result),
470
gpgme_strerror(import_status->result));
472
fprintf_plus(stderr, "Key status:\n");
474
import_status->status & GPGME_IMPORT_NEW
475
? "The key was new.\n"
476
: "The key was not new.\n");
478
import_status->status & GPGME_IMPORT_UID
479
? "The key contained new user IDs.\n"
480
: "The key did not contain new user IDs.\n");
482
import_status->status & GPGME_IMPORT_SIG
483
? "The key contained new signatures.\n"
484
: "The key did not contain new signatures.\n");
486
import_status->status & GPGME_IMPORT_SUBKEY
487
? "The key contained new sub keys.\n"
488
: "The key did not contain new sub keys.\n");
490
import_status->status & GPGME_IMPORT_SECRET
491
? "The key contained a secret key.\n"
492
: "The key did not contain a secret key.\n");
278
ret = (int)TEMP_FAILURE_RETRY(close(fd));
500
280
perror_plus("close");
592
372
/* Decrypt data from the cryptotext data buffer to the plaintext
594
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
374
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
595
375
if(rc != GPG_ERR_NO_ERROR){
596
376
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
597
377
gpgme_strsource(rc), gpgme_strerror(rc));
598
378
plaintext_length = -1;
600
380
gpgme_decrypt_result_t result;
601
result = gpgme_op_decrypt_result(mc->ctx);
381
result = gpgme_op_decrypt_result(mc.ctx);
602
382
if(result == NULL){
603
383
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
605
if(result->unsupported_algorithm != NULL) {
606
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
607
result->unsupported_algorithm);
609
fprintf_plus(stderr, "Wrong key usage: %s\n",
610
result->wrong_key_usage ? "Yes" : "No");
385
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
386
result->unsupported_algorithm);
387
fprintf_plus(stderr, "Wrong key usage: %u\n",
388
result->wrong_key_usage);
611
389
if(result->file_name != NULL){
612
390
fprintf_plus(stderr, "File name: %s\n", result->file_name);
615
for(gpgme_recipient_t r = result->recipients; r != NULL;
392
gpgme_recipient_t recipient;
393
recipient = result->recipients;
394
while(recipient != NULL){
617
395
fprintf_plus(stderr, "Public key algorithm: %s\n",
618
gpgme_pubkey_algo_name(r->pubkey_algo));
619
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
396
gpgme_pubkey_algo_name
397
(recipient->pubkey_algo));
398
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
620
399
fprintf_plus(stderr, "Secret key available: %s\n",
621
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
400
recipient->status == GPG_ERR_NO_SECKEY
402
recipient = recipient->next;
765
529
/* GnuTLS server initialization */
766
ret = gnutls_dh_params_init(&mc->dh_params);
530
ret = gnutls_dh_params_init(&mc.dh_params);
767
531
if(ret != GNUTLS_E_SUCCESS){
768
532
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
769
533
" initialization: %s\n",
770
534
safer_gnutls_strerror(ret));
773
/* If a Diffie-Hellman parameters file was given, try to use it */
774
if(dhparamsfilename != NULL){
775
gnutls_datum_t params = { .data = NULL, .size = 0 };
777
int dhpfile = open(dhparamsfilename, O_RDONLY);
780
dhparamsfilename = NULL;
783
size_t params_capacity = 0;
785
params_capacity = incbuffer((char **)¶ms.data,
787
(size_t)params_capacity);
788
if(params_capacity == 0){
789
perror_plus("incbuffer");
792
dhparamsfilename = NULL;
795
ssize_t bytes_read = read(dhpfile,
796
params.data + params.size,
802
/* check bytes_read for failure */
807
dhparamsfilename = NULL;
810
params.size += (unsigned int)bytes_read;
812
ret = close(dhpfile);
814
perror_plus("close");
816
if(params.data == NULL){
817
dhparamsfilename = NULL;
819
if(dhparamsfilename == NULL){
822
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
823
GNUTLS_X509_FMT_PEM);
824
if(ret != GNUTLS_E_SUCCESS){
825
fprintf_plus(stderr, "Failed to parse DH parameters in file"
826
" \"%s\": %s\n", dhparamsfilename,
827
safer_gnutls_strerror(ret));
828
dhparamsfilename = NULL;
833
if(dhparamsfilename == NULL){
834
if(mc->dh_bits == 0){
835
#if GNUTLS_VERSION_NUMBER < 0x030600
836
/* Find out the optimal number of DH bits */
837
/* Try to read the private key file */
838
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
840
int secfile = open(seckeyfilename, O_RDONLY);
845
size_t buffer_capacity = 0;
847
buffer_capacity = incbuffer((char **)&buffer.data,
849
(size_t)buffer_capacity);
850
if(buffer_capacity == 0){
851
perror_plus("incbuffer");
856
ssize_t bytes_read = read(secfile,
857
buffer.data + buffer.size,
863
/* check bytes_read for failure */
870
buffer.size += (unsigned int)bytes_read;
874
/* If successful, use buffer to parse private key */
875
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
876
if(buffer.data != NULL){
878
gnutls_openpgp_privkey_t privkey = NULL;
879
ret = gnutls_openpgp_privkey_init(&privkey);
880
if(ret != GNUTLS_E_SUCCESS){
881
fprintf_plus(stderr, "Error initializing OpenPGP key"
883
safer_gnutls_strerror(ret));
887
ret = gnutls_openpgp_privkey_import
888
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
889
if(ret != GNUTLS_E_SUCCESS){
890
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
891
safer_gnutls_strerror(ret));
897
/* Use private key to suggest an appropriate
899
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
900
gnutls_openpgp_privkey_deinit(privkey);
902
fprintf_plus(stderr, "This OpenPGP key implies using"
903
" a GnuTLS security parameter \"%s\".\n",
904
safe_string(gnutls_sec_param_get_name
910
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
911
/* Err on the side of caution */
912
sec_param = GNUTLS_SEC_PARAM_ULTRA;
914
fprintf_plus(stderr, "Falling back to security parameter"
916
safe_string(gnutls_sec_param_get_name
921
unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
925
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
926
" implies %u DH bits; using that.\n",
927
safe_string(gnutls_sec_param_get_name
932
fprintf_plus(stderr, "Failed to get implied number of DH"
933
" bits for security parameter \"%s\"): %s\n",
934
safe_string(gnutls_sec_param_get_name
936
safer_gnutls_strerror(ret));
940
} else { /* dh_bits != 0 */
942
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
945
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
946
if(ret != GNUTLS_E_SUCCESS){
947
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
948
" bits): %s\n", mc->dh_bits,
949
safer_gnutls_strerror(ret));
952
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
537
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
538
if(ret != GNUTLS_E_SUCCESS){
539
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
540
safer_gnutls_strerror(ret));
544
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
960
gnutls_certificate_free_credentials(mc->cred);
961
gnutls_dh_params_deinit(mc->dh_params);
550
gnutls_certificate_free_credentials(mc.cred);
551
gnutls_global_deinit();
552
gnutls_dh_params_deinit(mc.dh_params);
965
__attribute__((nonnull, warn_unused_result))
966
static int init_gnutls_session(gnutls_session_t *session,
556
static int init_gnutls_session(gnutls_session_t *session){
969
558
/* GnuTLS session creation */
971
ret = gnutls_init(session, (GNUTLS_SERVER
972
#if GNUTLS_VERSION_NUMBER >= 0x030506
975
#if GNUTLS_VERSION_NUMBER >= 0x030606
976
| GNUTLS_ENABLE_RAWPK
560
ret = gnutls_init(session, GNUTLS_SERVER);
1029
613
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
1030
614
__attribute__((unused)) const char *txt){}
1032
/* Helper function to add_local_route() and delete_local_route() */
1033
__attribute__((nonnull, warn_unused_result))
1034
static bool add_delete_local_route(const bool add,
1035
const char *address,
1036
AvahiIfIndex if_index){
1038
char helper[] = "mandos-client-iprouteadddel";
1039
char add_arg[] = "add";
1040
char delete_arg[] = "delete";
1041
char debug_flag[] = "--debug";
1042
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1043
if(pluginhelperdir == NULL){
1045
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
1046
" variable not set; cannot run helper\n");
1051
char interface[IF_NAMESIZE];
1052
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1053
perror_plus("if_indextoname");
1057
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1059
perror_plus("open(\"/dev/null\", O_RDONLY)");
1065
/* Raise privileges */
1066
errno = raise_privileges_permanently();
1068
perror_plus("Failed to raise privileges");
1069
/* _exit(EX_NOPERM); */
1075
perror_plus("setgid");
1079
/* Reset supplementary groups */
1081
ret = setgroups(0, NULL);
1083
perror_plus("setgroups");
1088
ret = dup2(devnull, STDIN_FILENO);
1090
perror_plus("dup2(devnull, STDIN_FILENO)");
1094
ret = close(devnull);
1096
perror_plus("close");
1098
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1100
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1103
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1108
if(helperdir_fd == -1){
1109
perror_plus("open");
1110
_exit(EX_UNAVAILABLE);
1112
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1114
if(helper_fd == -1){
1115
perror_plus("openat");
1116
close(helperdir_fd);
1117
_exit(EX_UNAVAILABLE);
1119
close(helperdir_fd);
1121
#pragma GCC diagnostic push
1122
#pragma GCC diagnostic ignored "-Wcast-qual"
1124
if(fexecve(helper_fd, (char *const [])
1125
{ helper, add ? add_arg : delete_arg, (char *)address,
1126
interface, debug ? debug_flag : NULL, NULL },
1129
#pragma GCC diagnostic pop
1131
perror_plus("fexecve");
1132
_exit(EXIT_FAILURE);
1136
perror_plus("fork");
1140
ret = close(devnull);
1142
perror_plus("close");
1148
pret = waitpid(pid, &status, 0);
1149
if(pret == -1 and errno == EINTR and quit_now){
1150
int errno_raising = 0;
1151
if((errno = raise_privileges()) != 0){
1152
errno_raising = errno;
1153
perror_plus("Failed to raise privileges in order to"
1154
" kill helper program");
1156
if(kill(pid, SIGTERM) == -1){
1157
perror_plus("kill");
1159
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1160
perror_plus("Failed to lower privileges after killing"
1165
} while(pret == -1 and errno == EINTR);
1167
perror_plus("waitpid");
1170
if(WIFEXITED(status)){
1171
if(WEXITSTATUS(status) != 0){
1172
fprintf_plus(stderr, "Error: iprouteadddel exited"
1173
" with status %d\n", WEXITSTATUS(status));
1178
if(WIFSIGNALED(status)){
1179
fprintf_plus(stderr, "Error: iprouteadddel died by"
1180
" signal %d\n", WTERMSIG(status));
1183
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1187
__attribute__((nonnull, warn_unused_result))
1188
static bool add_local_route(const char *address,
1189
AvahiIfIndex if_index){
1191
fprintf_plus(stderr, "Adding route to %s\n", address);
1193
return add_delete_local_route(true, address, if_index);
1196
__attribute__((nonnull, warn_unused_result))
1197
static bool delete_local_route(const char *address,
1198
AvahiIfIndex if_index){
1200
fprintf_plus(stderr, "Removing route to %s\n", address);
1202
return add_delete_local_route(false, address, if_index);
1205
616
/* Called when a Mandos server is found */
1206
__attribute__((nonnull, warn_unused_result))
1207
static int start_mandos_communication(const char *ip, in_port_t port,
617
static int start_mandos_communication(const char *ip, uint16_t port,
1208
618
AvahiIfIndex if_index,
1209
int af, mandos_context *mc){
1210
620
int ret, tcp_sd = -1;
1212
struct sockaddr_storage to;
623
struct sockaddr_in in;
624
struct sockaddr_in6 in6;
1213
626
char *buffer = NULL;
1214
627
char *decrypted_buffer = NULL;
1215
628
size_t buffer_length = 0;
1345
729
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1346
730
perror_plus("if_indextoname");
1348
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1349
"\n", ip, interface, (uintmax_t)port);
732
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
733
"\n", ip, interface, port);
1352
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1353
ip, (uintmax_t)port);
736
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
1355
739
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1356
740
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1358
ret = getnameinfo((struct sockaddr *)&to,
1359
sizeof(struct sockaddr_in6),
1360
addrstr, sizeof(addrstr), NULL, 0,
1363
ret = getnameinfo((struct sockaddr *)&to,
1364
sizeof(struct sockaddr_in),
1365
addrstr, sizeof(addrstr), NULL, 0,
1368
if(ret == EAI_SYSTEM){
1369
perror_plus("getnameinfo");
1370
} else if(ret != 0) {
1371
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1372
} else if(strcmp(addrstr, ip) != 0){
1373
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1384
ret = connect(tcp_sd, (struct sockaddr *)&to,
1385
sizeof(struct sockaddr_in6));
1387
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1388
sizeof(struct sockaddr_in));
1391
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1392
and if_index != AVAHI_IF_UNSPEC
1393
and connect_to == NULL
1394
and not route_added and
1395
((af == AF_INET6 and not
1396
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1398
or (af == AF_INET and
1399
/* Not a a IPv4LL address */
1400
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1401
& 0xFFFF0000L) != 0xA9FE0000L))){
1402
/* Work around Avahi bug - Avahi does not announce link-local
1403
addresses if it has a global address, so local hosts with
1404
*only* a link-local address (e.g. Mandos clients) cannot
1405
connect to a Mandos server announced by Avahi on a server
1406
host with a global address. Work around this by retrying
1407
with an explicit route added with the server's address.
1409
Avahi bug reference:
1410
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1411
https://bugs.debian.org/587961
1414
fprintf_plus(stderr, "Mandos server unreachable, trying"
1418
route_added = add_local_route(ip, if_index);
1424
if(errno != ECONNREFUSED or debug){
1426
perror_plus("connect");
743
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
746
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
750
perror_plus("inet_ntop");
752
if(strcmp(addrstr, ip) != 0){
753
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
764
ret = connect(tcp_sd, &to.in6, sizeof(to));
766
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
769
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
771
perror_plus("connect");
1439
782
const char *out = mandos_protocol_version;
2073
1374
ret = avahi_simple_poll_iterate(s, (int)block_time);
2076
if(ret > 0 or errno != EINTR){
1377
if (ret > 0 or errno != EINTR){
2077
1378
return (ret != 1) ? ret : 0;
2083
__attribute__((nonnull))
2084
void run_network_hooks(const char *mode, const char *interface,
1384
bool run_network_hooks(const char *mode, const char *interface,
2085
1385
const float delay){
2086
struct dirent **direntries = NULL;
2087
if(hookdir_fd == -1){
2088
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2090
if(hookdir_fd == -1){
2091
if(errno == ENOENT){
2093
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2094
" found\n", hookdir);
2097
perror_plus("open");
2102
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2104
perror_plus("open(\"/dev/null\", O_RDONLY)");
2107
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2108
runnable_hook, alphasort);
1386
struct dirent **direntries;
1387
struct dirent *direntry;
1389
int numhooks = scandir(hookdir, &direntries, runnable_hook,
2109
1391
if(numhooks == -1){
2110
1392
perror_plus("scandir");
2114
struct dirent *direntry;
2116
for(int i = 0; i < numhooks; i++){
2117
direntry = direntries[i];
2119
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2122
pid_t hook_pid = fork();
2125
/* Raise privileges */
2126
errno = raise_privileges_permanently();
2128
perror_plus("Failed to raise privileges");
2135
perror_plus("setgid");
2138
/* Reset supplementary groups */
2140
ret = setgroups(0, NULL);
2142
perror_plus("setgroups");
2145
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2147
perror_plus("setenv");
2150
ret = setenv("DEVICE", interface, 1);
2152
perror_plus("setenv");
2155
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2157
perror_plus("setenv");
2160
ret = setenv("MODE", mode, 1);
2162
perror_plus("setenv");
2166
ret = asprintf(&delaystring, "%f", (double)delay);
1394
int devnull = open("/dev/null", O_RDONLY);
1395
for(int i = 0; i < numhooks; i++){
1396
direntry = direntries[i];
1397
char *fullname = NULL;
1398
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
2168
1400
perror_plus("asprintf");
2171
ret = setenv("DELAY", delaystring, 1);
1404
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1407
pid_t hook_pid = fork();
1410
/* Raise privileges */
1414
perror_plus("seteuid");
1416
/* Raise privileges even more */
1420
perror_plus("setuid");
1426
perror_plus("setgid");
1428
/* Reset supplementary groups */
1430
ret = setgroups(0, NULL);
1432
perror_plus("setgroups");
1434
fprintf_plus(stderr, "Child: getuid() = %d\n", getuid());
1435
fprintf_plus(stderr, "Child: geteuid() = %d\n", geteuid());
1436
dup2(devnull, STDIN_FILENO);
1438
dup2(STDERR_FILENO, STDOUT_FILENO);
1439
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1441
perror_plus("setenv");
1444
ret = setenv("DEVICE", interface, 1);
1446
perror_plus("setenv");
1449
ret = setenv("VERBOSE", debug ? "1" : "0", 1);
1451
perror_plus("setenv");
1454
ret = setenv("MODE", mode, 1);
1456
perror_plus("setenv");
1460
ret = asprintf(&delaystring, "%f", delay);
1462
perror_plus("asprintf");
1465
ret = setenv("DELAY", delaystring, 1);
1468
perror_plus("setenv");
2173
1471
free(delaystring);
2174
perror_plus("setenv");
2178
if(connect_to != NULL){
2179
ret = setenv("CONNECT", connect_to, 1);
2181
perror_plus("setenv");
2185
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2189
perror_plus("openat");
2190
_exit(EXIT_FAILURE);
2192
if(close(hookdir_fd) == -1){
2193
perror_plus("close");
2194
_exit(EXIT_FAILURE);
2196
ret = dup2(devnull, STDIN_FILENO);
2198
perror_plus("dup2(devnull, STDIN_FILENO)");
2201
ret = close(devnull);
2203
perror_plus("close");
2206
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2208
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2211
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2213
perror_plus("fexecve");
2214
_exit(EXIT_FAILURE);
2218
perror_plus("fork");
2223
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2224
perror_plus("waitpid");
2228
if(WIFEXITED(status)){
2229
if(WEXITSTATUS(status) != 0){
2230
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2231
" with status %d\n", direntry->d_name,
2232
WEXITSTATUS(status));
2236
} else if(WIFSIGNALED(status)){
2237
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2238
" signal %d\n", direntry->d_name,
2243
fprintf_plus(stderr, "Warning: network hook \"%s\""
2244
" crashed\n", direntry->d_name);
2250
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2256
if(close(hookdir_fd) == -1){
2257
perror_plus("close");
2264
__attribute__((nonnull, warn_unused_result))
2265
int bring_up_interface(const char *const interface,
2267
int old_errno = errno;
2269
struct ifreq network;
2270
unsigned int if_index = if_nametoindex(interface);
2272
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2282
if(not interface_is_up(interface)){
2284
int ioctl_errno = 0;
2285
if(not get_flags(interface, &network)){
2287
fprintf_plus(stderr, "Failed to get flags for interface "
2288
"\"%s\"\n", interface);
2292
network.ifr_flags |= IFF_UP; /* set flag */
2294
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2297
perror_plus("socket");
2305
perror_plus("close");
2312
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2316
/* Raise privileges */
2317
ret_errno = raise_privileges();
2320
perror_plus("Failed to raise privileges");
2325
bool restore_loglevel = false;
2327
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2328
messages about the network interface to mess up the prompt */
2329
ret_linux = klogctl(8, NULL, 5);
2330
if(ret_linux == -1){
2331
perror_plus("klogctl");
2333
restore_loglevel = true;
2336
#endif /* __linux__ */
2337
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2338
ioctl_errno = errno;
2340
if(restore_loglevel){
2341
ret_linux = klogctl(7, NULL, 0);
2342
if(ret_linux == -1){
2343
perror_plus("klogctl");
2346
#endif /* __linux__ */
2348
/* If raise_privileges() succeeded above */
2350
/* Lower privileges */
2351
ret_errno = lower_privileges();
2354
perror_plus("Failed to lower privileges");
2358
/* Close the socket */
2361
perror_plus("close");
2364
if(ret_setflags == -1){
2365
errno = ioctl_errno;
2366
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2371
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2375
/* Sleep checking until interface is running.
2376
Check every 0.25s, up to total time of delay */
2377
for(int i = 0; i < delay * 4; i++){
2378
if(interface_is_running(interface)){
2381
struct timespec sleeptime = { .tv_nsec = 250000000 };
2382
ret = nanosleep(&sleeptime, NULL);
2383
if(ret == -1 and errno != EINTR){
2384
perror_plus("nanosleep");
2392
__attribute__((nonnull, warn_unused_result))
2393
int take_down_interface(const char *const interface){
2394
int old_errno = errno;
2395
struct ifreq network;
2396
unsigned int if_index = if_nametoindex(interface);
2398
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2402
if(interface_is_up(interface)){
2404
int ioctl_errno = 0;
2405
if(not get_flags(interface, &network) and debug){
2407
fprintf_plus(stderr, "Failed to get flags for interface "
2408
"\"%s\"\n", interface);
2412
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2414
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2417
perror_plus("socket");
2423
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2427
/* Raise privileges */
2428
ret_errno = raise_privileges();
2431
perror_plus("Failed to raise privileges");
2434
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2435
ioctl_errno = errno;
2437
/* If raise_privileges() succeeded above */
2439
/* Lower privileges */
2440
ret_errno = lower_privileges();
2443
perror_plus("Failed to lower privileges");
2447
/* Close the socket */
2448
int ret = close(sd);
2450
perror_plus("close");
2453
if(ret_setflags == -1){
2454
errno = ioctl_errno;
2455
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2460
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1472
ret = execl(fullname, direntry->d_name, mode, NULL);
1473
perror_plus("execl");
1476
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1477
perror_plus("waitpid");
1481
if(WIFEXITED(status)){
1482
if(WEXITSTATUS(status) != 0){
1483
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1484
" with status %d\n", direntry->d_name,
1485
WEXITSTATUS(status));
1489
} else if(WIFSIGNALED(status)){
1490
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1491
" signal %d\n", direntry->d_name,
1496
fprintf_plus(stderr, "Warning: network hook \"%s\""
1497
" crashed\n", direntry->d_name);
1504
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2468
1513
int main(int argc, char *argv[]){
2469
mandos_context mc = { .server = NULL, .dh_bits = 0,
2470
#if GNUTLS_VERSION_NUMBER >= 0x030606
2471
.priority = "SECURE128:!CTYPE-X.509"
2472
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2474
#elif GNUTLS_VERSION_NUMBER < 0x030600
2475
.priority = "SECURE256:!CTYPE-X.509"
2476
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2478
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2480
.current_server = NULL, .interfaces = NULL,
2481
.interfaces_size = 0 };
2482
1514
AvahiSServiceBrowser *sb = NULL;
2485
1517
intmax_t tmpmax;
2487
1519
int exitcode = EXIT_SUCCESS;
2488
char *interfaces_to_take_down = NULL;
2489
size_t interfaces_to_take_down_size = 0;
2490
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2491
char old_tempdir[] = "/tmp/mandosXXXXXX";
2492
char *tempdir = NULL;
1520
const char *interface = "";
1521
struct ifreq network;
1523
bool take_down_interface = false;
1526
char tempdir[] = "/tmp/mandosXXXXXX";
1527
bool tempdir_created = false;
2493
1528
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2494
1529
const char *seckey = PATHDIR "/" SECKEY;
2495
1530
const char *pubkey = PATHDIR "/" PUBKEY;
2496
#if GNUTLS_VERSION_NUMBER >= 0x030606
2497
const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;
2498
const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;
2500
const char *dh_params_file = NULL;
2501
char *interfaces_hooks = NULL;
2503
1532
bool gnutls_initialized = false;
2504
1533
bool gpgme_initialized = false;
2771
if(dh_params_file != NULL
2772
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2773
int dhparams_fd = open(dh_params_file, O_RDONLY);
2774
if(dhparams_fd == -1){
2775
perror_plus("open");
2777
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2779
perror_plus("fstat");
2781
if(S_ISREG(st.st_mode)
2782
and st.st_uid == 0 and st.st_gid == 0){
2783
ret = fchown(dhparams_fd, uid, gid);
2785
perror_plus("fchown");
1758
TEMP_FAILURE_RETRY(close(pubkey_fd));
2793
1762
/* Lower privileges */
2794
ret = lower_privileges();
2797
perror_plus("Failed to lower privileges");
2802
/* Remove invalid interface names (except "none") */
2804
char *interface = NULL;
2805
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2807
if(strcmp(interface, "none") != 0
2808
and if_nametoindex(interface) == 0){
2809
if(interface[0] != '\0'){
2810
fprintf_plus(stderr, "Not using nonexisting interface"
2811
" \"%s\"\n", interface);
2813
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
1766
perror_plus("seteuid");
2819
1771
/* Run network hooks */
2821
if(mc.interfaces != NULL){
2822
interfaces_hooks = malloc(mc.interfaces_size);
2823
if(interfaces_hooks == NULL){
2824
perror_plus("malloc");
2827
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2828
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2830
run_network_hooks("start", interfaces_hooks != NULL ?
2831
interfaces_hooks : "", delay);
1772
if(not run_network_hooks("start", interface, delay)){
2835
1777
avahi_set_log_function(empty_log);
1780
if(interface[0] == '\0'){
1781
struct dirent **direntries;
1782
/* First look for interfaces that are up */
1783
ret = scandir(sys_class_net, &direntries, up_interface,
1786
/* No up interfaces, look for any good interfaces */
1788
ret = scandir(sys_class_net, &direntries, good_interface,
1792
/* Pick the first interface returned */
1793
interface = strdup(direntries[0]->d_name);
1795
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1797
if(interface == NULL){
1798
perror_plus("malloc");
1800
exitcode = EXIT_FAILURE;
1806
fprintf_plus(stderr, "Could not find a network interface\n");
1807
exitcode = EXIT_FAILURE;
2838
1812
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2839
1813
from the signal handler */
2840
1814
/* Initialize the pseudo-RNG for Avahi */
2841
1815
srand((unsigned int) time(NULL));
2842
simple_poll = avahi_simple_poll_new();
2843
if(simple_poll == NULL){
1816
mc.simple_poll = avahi_simple_poll_new();
1817
if(mc.simple_poll == NULL){
2844
1818
fprintf_plus(stderr,
2845
1819
"Avahi: Failed to create simple poll object.\n");
2846
1820
exitcode = EX_UNAVAILABLE;
2913
/* If no interfaces were specified, make a list */
2914
if(mc.interfaces == NULL){
2915
struct dirent **direntries = NULL;
2916
/* Look for any good interfaces */
2917
ret = scandir(sys_class_net, &direntries, good_interface,
2920
/* Add all found interfaces to interfaces list */
2921
for(int i = 0; i < ret; ++i){
2922
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2923
direntries[i]->d_name);
2926
perror_plus("argz_add");
2927
free(direntries[i]);
2931
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2932
direntries[i]->d_name);
2934
free(direntries[i]);
2941
fprintf_plus(stderr, "Could not find a network interface\n");
2942
exitcode = EXIT_FAILURE;
2947
/* Bring up interfaces which are down, and remove any "none"s */
2949
char *interface = NULL;
2950
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2952
/* If interface name is "none", stop bringing up interfaces.
2953
Also remove all instances of "none" from the list */
2954
if(strcmp(interface, "none") == 0){
2955
argz_delete(&mc.interfaces, &mc.interfaces_size,
2958
while((interface = argz_next(mc.interfaces,
2959
mc.interfaces_size, interface))){
2960
if(strcmp(interface, "none") == 0){
2961
argz_delete(&mc.interfaces, &mc.interfaces_size,
1887
/* If the interface is down, bring it up */
1888
if(strcmp(interface, "none") != 0){
1889
if_index = (AvahiIfIndex) if_nametoindex(interface);
1891
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1892
exitcode = EX_UNAVAILABLE;
1900
/* Re-raise priviliges */
1904
perror_plus("seteuid");
1908
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1909
messages about the network interface to mess up the prompt */
1910
ret = klogctl(8, NULL, 5);
1911
bool restore_loglevel = true;
1913
restore_loglevel = false;
1914
perror_plus("klogctl");
1916
#endif /* __linux__ */
1918
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1920
perror_plus("socket");
1921
exitcode = EX_OSERR;
1923
if(restore_loglevel){
1924
ret = klogctl(7, NULL, 0);
1926
perror_plus("klogctl");
1929
#endif /* __linux__ */
1930
/* Lower privileges */
1934
perror_plus("seteuid");
1938
strcpy(network.ifr_name, interface);
1939
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1941
perror_plus("ioctl SIOCGIFFLAGS");
1943
if(restore_loglevel){
1944
ret = klogctl(7, NULL, 0);
1946
perror_plus("klogctl");
1949
#endif /* __linux__ */
1950
exitcode = EX_OSERR;
1951
/* Lower privileges */
1955
perror_plus("seteuid");
1959
if((network.ifr_flags & IFF_UP) == 0){
1960
network.ifr_flags |= IFF_UP;
1961
take_down_interface = true;
1962
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1964
take_down_interface = false;
1965
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1966
exitcode = EX_OSERR;
1968
if(restore_loglevel){
1969
ret = klogctl(7, NULL, 0);
1971
perror_plus("klogctl");
1974
#endif /* __linux__ */
1975
/* Lower privileges */
1979
perror_plus("seteuid");
1984
/* Sleep checking until interface is running.
1985
Check every 0.25s, up to total time of delay */
1986
for(int i=0; i < delay * 4; i++){
1987
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1989
perror_plus("ioctl SIOCGIFFLAGS");
1990
} else if(network.ifr_flags & IFF_RUNNING){
2968
bool interface_was_up = interface_is_up(interface);
2969
errno = bring_up_interface(interface, delay);
2970
if(not interface_was_up){
2972
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2973
" %s\n", interface, strerror(errno));
2975
errno = argz_add(&interfaces_to_take_down,
2976
&interfaces_to_take_down_size,
2979
perror_plus("argz_add");
2984
if(debug and (interfaces_to_take_down == NULL)){
2985
fprintf_plus(stderr, "No interfaces were brought up\n");
2989
/* If we only got one interface, explicitly use only that one */
2990
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2992
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2995
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1993
struct timespec sleeptime = { .tv_nsec = 250000000 };
1994
ret = nanosleep(&sleeptime, NULL);
1995
if(ret == -1 and errno != EINTR){
1996
perror_plus("nanosleep");
1999
if(not take_down_interface){
2000
/* We won't need the socket anymore */
2001
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2003
perror_plus("close");
2007
if(restore_loglevel){
2008
/* Restores kernel loglevel to default */
2009
ret = klogctl(7, NULL, 0);
2011
perror_plus("klogctl");
2014
#endif /* __linux__ */
2015
/* Lower privileges */
2017
/* Lower privileges */
2020
perror_plus("seteuid");
3002
#if GNUTLS_VERSION_NUMBER >= 0x030606
3003
ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);
3004
#elif GNUTLS_VERSION_NUMBER < 0x030600
3005
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
3007
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2028
ret = init_gnutls_global(pubkey, seckey);
3010
2030
fprintf_plus(stderr, "init_gnutls_global failed\n");
3011
2031
exitcode = EX_UNAVAILABLE;
3219
2222
mc.current_server->prev->next = NULL;
3220
2223
while(mc.current_server != NULL){
3221
2224
server *next = mc.current_server->next;
3223
#pragma GCC diagnostic push
3224
#pragma GCC diagnostic ignored "-Wcast-qual"
3226
free((char *)(mc.current_server->ip));
3228
#pragma GCC diagnostic pop
3230
2225
free(mc.current_server);
3231
2226
mc.current_server = next;
3235
/* Re-raise privileges */
2230
/* Run network hooks */
2231
run_network_hooks("stop", interface, delay);
2233
/* Re-raise priviliges */
3237
ret = raise_privileges();
3240
perror_plus("Failed to raise privileges");
3243
/* Run network hooks */
3244
run_network_hooks("stop", interfaces_hooks != NULL ?
3245
interfaces_hooks : "", delay);
3247
/* Take down the network interfaces which were brought up */
3249
char *interface = NULL;
3250
while((interface = argz_next(interfaces_to_take_down,
3251
interfaces_to_take_down_size,
3253
ret = take_down_interface(interface);
3256
perror_plus("Failed to take down interface");
3259
if(debug and (interfaces_to_take_down == NULL)){
3260
fprintf_plus(stderr, "No interfaces needed to be taken"
2238
perror_plus("seteuid");
3266
ret = lower_privileges_permanently();
3269
perror_plus("Failed to lower privileges permanently");
2241
/* Take down the network interface */
2242
if(take_down_interface and geteuid() == 0){
2243
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2245
perror_plus("ioctl SIOCGIFFLAGS");
2246
} else if(network.ifr_flags & IFF_UP){
2247
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2248
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2250
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2253
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2255
perror_plus("close");
3273
free(interfaces_to_take_down);
3274
free(interfaces_hooks);
3276
void clean_dir_at(int base, const char * const dirname,
2259
/* Lower privileges permanently */
2263
perror_plus("setuid");
2266
/* Removes the GPGME temp directory and all files inside */
2267
if(tempdir_created){
3278
2268
struct dirent **direntries = NULL;
3280
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3286
perror_plus("open");
3289
int numentries = scandirat(dir_fd, ".", &direntries,
3290
notdotentries, alphasort);
3291
if(numentries >= 0){
2269
struct dirent *direntry = NULL;
2270
int numentries = scandir(tempdir, &direntries, notdotentries,
2272
if (numentries > 0){
3292
2273
for(int i = 0; i < numentries; i++){
3294
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3295
dirname, direntries[i]->d_name);
3297
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3299
if(errno == EISDIR){
3300
dret = unlinkat(dir_fd, direntries[i]->d_name,
3303
if((dret == -1) and (errno == ENOTEMPTY)
3304
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3305
== 0) and (level == 0)){
3306
/* Recurse only in this special case */
3307
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3310
if((dret == -1) and (errno != ENOENT)){
3311
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3312
direntries[i]->d_name, strerror(errno));
3315
free(direntries[i]);
3318
/* need to clean even if 0 because man page doesn't specify */
3320
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3321
if(dret == -1 and errno != ENOENT){
3322
perror_plus("rmdir");
3325
perror_plus("scandirat");
3330
/* Removes the GPGME temp directory and all files inside */
3331
if(tempdir != NULL){
3332
clean_dir_at(-1, tempdir, 0);
2274
direntry = direntries[i];
2275
char *fullname = NULL;
2276
ret = asprintf(&fullname, "%s/%s", tempdir,
2279
perror_plus("asprintf");
2282
ret = remove(fullname);
2284
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2291
/* need to clean even if 0 because man page doesn't specify */
2293
if (numentries == -1){
2294
perror_plus("scandir");
2296
ret = rmdir(tempdir);
2297
if(ret == -1 and errno != ENOENT){
2298
perror_plus("rmdir");