32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
33
34
#ifndef _LARGEFILE_SOURCE
34
35
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
36
37
#ifndef _FILE_OFFSET_BITS
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38
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
40
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
46
#include <stddef.h> /* NULL, size_t, ssize_t */
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47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
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48
strtof(), abort() */
48
49
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
51
53
#include <sys/ioctl.h> /* ioctl */
52
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
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55
sockaddr_in6, PF_INET6,
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56
SOCK_STREAM, uid_t, gid_t, open(),
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#include <sys/stat.h> /* open() */
58
#include <sys/stat.h> /* open(), S_ISREG */
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59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno,
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
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EAI_SYSTEM, ENETUNREACH,
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EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
66
72
program_invocation_short_name */
67
73
#include <time.h> /* nanosleep(), time(), sleep() */
68
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
184
214
* bytes. "buffer_capacity" is how much is currently allocated,
185
215
* "buffer_length" is how much is already used.
217
__attribute__((nonnull, warn_unused_result))
187
218
size_t incbuffer(char **buffer, size_t buffer_length,
188
size_t buffer_capacity){
219
size_t buffer_capacity){
189
220
if(buffer_length + BUFFER_SIZE > buffer_capacity){
190
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
221
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
223
int old_errno = errno;
194
230
buffer_capacity += BUFFER_SIZE;
196
232
return buffer_capacity;
199
235
/* Add server to set of servers to retry periodically */
200
int add_server(const char *ip, uint16_t port,
201
AvahiIfIndex if_index,
236
__attribute__((nonnull, warn_unused_result))
237
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
238
int af, server **current_server){
204
240
server *new_server = malloc(sizeof(server));
205
241
if(new_server == NULL){
206
242
perror_plus("malloc");
209
245
*new_server = (server){ .ip = strdup(ip),
211
.if_index = if_index,
247
.if_index = if_index,
213
249
if(new_server->ip == NULL){
214
250
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
217
268
/* Special case of first server */
218
if (mc.current_server == NULL){
269
if(*current_server == NULL){
219
270
new_server->next = new_server;
220
271
new_server->prev = new_server;
221
mc.current_server = new_server;
222
/* Place the new server last in the list */
272
*current_server = new_server;
224
new_server->next = mc.current_server;
225
new_server->prev = mc.current_server->prev;
274
/* Place the new server last in the list */
275
new_server->next = *current_server;
276
new_server->prev = (*current_server)->prev;
226
277
new_server->prev->next = new_server;
227
mc.current_server->prev = new_server;
229
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
231
perror_plus("clock_gettime");
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){
238
336
* Initialize GPGME.
240
static bool init_gpgme(const char *seckey,
241
const char *pubkey, const char *tempdir){
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,
242
343
gpgme_error_t rc;
243
344
gpgme_engine_info_t engine_info;
247
347
* Helper function to insert pub and seckey to the engine keyring.
249
bool import_key(const char *filename){
349
bool import_key(const char * const filename){
252
352
gpgme_data_t pgp_data;
360
/* Workaround for systems without a real-time clock; see also
361
Debian bug #894495: <https://bugs.debian.org/894495> */
364
time_t currtime = time(NULL);
365
if(currtime != (time_t)-1){
367
if(gmtime_r(&currtime, &tm) == NULL) {
368
perror_plus("gmtime_r");
371
if(tm.tm_year != 70 or tm.tm_mon != 0){
375
fprintf_plus(stderr, "System clock is January 1970");
379
fprintf_plus(stderr, "System clock is invalid");
384
ret = fstat(fd, &keystat);
386
perror_plus("fstat");
389
ret = raise_privileges();
392
perror_plus("Failed to raise privileges");
397
"Setting system clock to key file mtime");
399
time_t keytime = keystat.st_mtim.tv_sec;
400
if(stime(&keytime) != 0){
401
perror_plus("stime");
403
ret = lower_privileges();
406
perror_plus("Failed to lower privileges");
260
410
rc = gpgme_data_new_from_fd(&pgp_data, fd);
261
411
if(rc != GPG_ERR_NO_ERROR){
262
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
263
gpgme_strsource(rc), gpgme_strerror(rc));
412
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
267
rc = gpgme_op_import(mc.ctx, pgp_data);
417
rc = gpgme_op_import(mc->ctx, pgp_data);
268
418
if(rc != GPG_ERR_NO_ERROR){
269
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
270
gpgme_strsource(rc), gpgme_strerror(rc));
419
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
420
gpgme_strsource(rc), gpgme_strerror(rc));
424
gpgme_import_result_t import_result
425
= gpgme_op_import_result(mc->ctx);
426
if((import_result->imported < 1
427
or import_result->not_imported > 0)
428
and import_result->unchanged == 0){
429
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
431
"The total number of considered keys: %d\n",
432
import_result->considered);
434
"The number of keys without user ID: %d\n",
435
import_result->no_user_id);
437
"The total number of imported keys: %d\n",
438
import_result->imported);
439
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
440
import_result->imported_rsa);
441
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
442
import_result->unchanged);
443
fprintf_plus(stderr, "The number of new user IDs: %d\n",
444
import_result->new_user_ids);
445
fprintf_plus(stderr, "The number of new sub keys: %d\n",
446
import_result->new_sub_keys);
447
fprintf_plus(stderr, "The number of new signatures: %d\n",
448
import_result->new_signatures);
449
fprintf_plus(stderr, "The number of new revocations: %d\n",
450
import_result->new_revocations);
452
"The total number of secret keys read: %d\n",
453
import_result->secret_read);
455
"The number of imported secret keys: %d\n",
456
import_result->secret_imported);
458
"The number of unchanged secret keys: %d\n",
459
import_result->secret_unchanged);
460
fprintf_plus(stderr, "The number of keys not imported: %d\n",
461
import_result->not_imported);
462
for(gpgme_import_status_t import_status
463
= import_result->imports;
464
import_status != NULL;
465
import_status = import_status->next){
466
fprintf_plus(stderr, "Import status for key: %s\n",
468
if(import_status->result != GPG_ERR_NO_ERROR){
469
fprintf_plus(stderr, "Import result: %s: %s\n",
470
gpgme_strsource(import_status->result),
471
gpgme_strerror(import_status->result));
473
fprintf_plus(stderr, "Key status:\n");
475
import_status->status & GPGME_IMPORT_NEW
476
? "The key was new.\n"
477
: "The key was not new.\n");
479
import_status->status & GPGME_IMPORT_UID
480
? "The key contained new user IDs.\n"
481
: "The key did not contain new user IDs.\n");
483
import_status->status & GPGME_IMPORT_SIG
484
? "The key contained new signatures.\n"
485
: "The key did not contain new signatures.\n");
487
import_status->status & GPGME_IMPORT_SUBKEY
488
? "The key contained new sub keys.\n"
489
: "The key did not contain new sub keys.\n");
491
import_status->status & GPGME_IMPORT_SECRET
492
? "The key contained a secret key.\n"
493
: "The key did not contain a secret key.\n");
274
ret = (int)TEMP_FAILURE_RETRY(close(fd));
276
501
perror_plus("close");
341
569
ssize_t plaintext_length = 0;
344
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
572
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
347
575
/* Create new GPGME data buffer from memory cryptotext */
348
576
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
350
578
if(rc != GPG_ERR_NO_ERROR){
351
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
352
gpgme_strsource(rc), gpgme_strerror(rc));
579
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
580
gpgme_strsource(rc), gpgme_strerror(rc));
356
584
/* Create new empty GPGME data buffer for the plaintext */
357
585
rc = gpgme_data_new(&dh_plain);
358
586
if(rc != GPG_ERR_NO_ERROR){
359
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
360
gpgme_strsource(rc), gpgme_strerror(rc));
587
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
588
gpgme_strsource(rc), gpgme_strerror(rc));
361
589
gpgme_data_release(dh_crypto);
365
593
/* Decrypt data from the cryptotext data buffer to the plaintext
367
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
595
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
368
596
if(rc != GPG_ERR_NO_ERROR){
369
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
370
gpgme_strsource(rc), gpgme_strerror(rc));
597
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
598
gpgme_strsource(rc), gpgme_strerror(rc));
371
599
plaintext_length = -1;
373
601
gpgme_decrypt_result_t result;
374
result = gpgme_op_decrypt_result(mc.ctx);
602
result = gpgme_op_decrypt_result(mc->ctx);
375
603
if(result == NULL){
376
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
604
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
378
fprintf(stderr, "Unsupported algorithm: %s\n",
379
result->unsupported_algorithm);
380
fprintf(stderr, "Wrong key usage: %u\n",
381
result->wrong_key_usage);
606
if(result->unsupported_algorithm != NULL) {
607
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
608
result->unsupported_algorithm);
610
fprintf_plus(stderr, "Wrong key usage: %s\n",
611
result->wrong_key_usage ? "Yes" : "No");
382
612
if(result->file_name != NULL){
383
fprintf(stderr, "File name: %s\n", result->file_name);
613
fprintf_plus(stderr, "File name: %s\n", result->file_name);
385
gpgme_recipient_t recipient;
386
recipient = result->recipients;
387
while(recipient != NULL){
388
fprintf(stderr, "Public key algorithm: %s\n",
389
gpgme_pubkey_algo_name(recipient->pubkey_algo));
390
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
391
fprintf(stderr, "Secret key available: %s\n",
392
recipient->status == GPG_ERR_NO_SECKEY
394
recipient = recipient->next;
616
for(gpgme_recipient_t r = result->recipients; r != NULL;
618
fprintf_plus(stderr, "Public key algorithm: %s\n",
619
gpgme_pubkey_algo_name(r->pubkey_algo));
620
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
621
fprintf_plus(stderr, "Secret key available: %s\n",
622
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
493
723
/* OpenPGP credentials */
494
ret = gnutls_certificate_allocate_credentials(&mc.cred);
724
ret = gnutls_certificate_allocate_credentials(&mc->cred);
495
725
if(ret != GNUTLS_E_SUCCESS){
496
fprintf(stderr, "GnuTLS memory error: %s\n",
497
safer_gnutls_strerror(ret));
498
gnutls_global_deinit();
726
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
727
safer_gnutls_strerror(ret));
503
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
504
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
732
fprintf_plus(stderr, "Attempting to use public key %s and"
733
" private key %s as GnuTLS credentials\n",
738
#if GNUTLS_VERSION_NUMBER >= 0x030606
739
ret = gnutls_certificate_set_rawpk_key_file
740
(mc->cred, pubkeyfilename, seckeyfilename,
741
GNUTLS_X509_FMT_PEM, /* format */
744
GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,
746
0, /* names_length */
748
GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,
749
0); /* pkcs11_flags */
750
#elif GNUTLS_VERSION_NUMBER < 0x030600
508
751
ret = gnutls_certificate_set_openpgp_key_file
509
(mc.cred, pubkeyfilename, seckeyfilename,
752
(mc->cred, pubkeyfilename, seckeyfilename,
510
753
GNUTLS_OPENPGP_FMT_BASE64);
755
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
511
757
if(ret != GNUTLS_E_SUCCESS){
513
"Error[%d] while reading the OpenPGP key pair ('%s',"
514
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
515
fprintf(stderr, "The GnuTLS error is: %s\n",
516
safer_gnutls_strerror(ret));
759
"Error[%d] while reading the key pair ('%s',"
760
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
761
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
762
safer_gnutls_strerror(ret));
520
766
/* GnuTLS server initialization */
521
ret = gnutls_dh_params_init(&mc.dh_params);
522
if(ret != GNUTLS_E_SUCCESS){
523
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
524
" %s\n", safer_gnutls_strerror(ret));
527
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
528
if(ret != GNUTLS_E_SUCCESS){
529
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
530
safer_gnutls_strerror(ret));
534
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
767
ret = gnutls_dh_params_init(&mc->dh_params);
768
if(ret != GNUTLS_E_SUCCESS){
769
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
770
" initialization: %s\n",
771
safer_gnutls_strerror(ret));
774
/* If a Diffie-Hellman parameters file was given, try to use it */
775
if(dhparamsfilename != NULL){
776
gnutls_datum_t params = { .data = NULL, .size = 0 };
778
int dhpfile = open(dhparamsfilename, O_RDONLY);
781
dhparamsfilename = NULL;
784
size_t params_capacity = 0;
786
params_capacity = incbuffer((char **)¶ms.data,
788
(size_t)params_capacity);
789
if(params_capacity == 0){
790
perror_plus("incbuffer");
793
dhparamsfilename = NULL;
796
ssize_t bytes_read = read(dhpfile,
797
params.data + params.size,
803
/* check bytes_read for failure */
808
dhparamsfilename = NULL;
811
params.size += (unsigned int)bytes_read;
813
ret = close(dhpfile);
815
perror_plus("close");
817
if(params.data == NULL){
818
dhparamsfilename = NULL;
820
if(dhparamsfilename == NULL){
823
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
824
GNUTLS_X509_FMT_PEM);
825
if(ret != GNUTLS_E_SUCCESS){
826
fprintf_plus(stderr, "Failed to parse DH parameters in file"
827
" \"%s\": %s\n", dhparamsfilename,
828
safer_gnutls_strerror(ret));
829
dhparamsfilename = NULL;
834
if(dhparamsfilename == NULL){
835
if(mc->dh_bits == 0){
836
#if GNUTLS_VERSION_NUMBER < 0x030600
837
/* Find out the optimal number of DH bits */
838
/* Try to read the private key file */
839
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
841
int secfile = open(seckeyfilename, O_RDONLY);
846
size_t buffer_capacity = 0;
848
buffer_capacity = incbuffer((char **)&buffer.data,
850
(size_t)buffer_capacity);
851
if(buffer_capacity == 0){
852
perror_plus("incbuffer");
857
ssize_t bytes_read = read(secfile,
858
buffer.data + buffer.size,
864
/* check bytes_read for failure */
871
buffer.size += (unsigned int)bytes_read;
875
/* If successful, use buffer to parse private key */
876
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
877
if(buffer.data != NULL){
879
gnutls_openpgp_privkey_t privkey = NULL;
880
ret = gnutls_openpgp_privkey_init(&privkey);
881
if(ret != GNUTLS_E_SUCCESS){
882
fprintf_plus(stderr, "Error initializing OpenPGP key"
884
safer_gnutls_strerror(ret));
888
ret = gnutls_openpgp_privkey_import
889
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
890
if(ret != GNUTLS_E_SUCCESS){
891
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
892
safer_gnutls_strerror(ret));
898
/* Use private key to suggest an appropriate
900
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
901
gnutls_openpgp_privkey_deinit(privkey);
903
fprintf_plus(stderr, "This OpenPGP key implies using"
904
" a GnuTLS security parameter \"%s\".\n",
905
safe_string(gnutls_sec_param_get_name
911
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
912
/* Err on the side of caution */
913
sec_param = GNUTLS_SEC_PARAM_ULTRA;
915
fprintf_plus(stderr, "Falling back to security parameter"
917
safe_string(gnutls_sec_param_get_name
922
unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
926
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
927
" implies %u DH bits; using that.\n",
928
safe_string(gnutls_sec_param_get_name
933
fprintf_plus(stderr, "Failed to get implied number of DH"
934
" bits for security parameter \"%s\"): %s\n",
935
safe_string(gnutls_sec_param_get_name
937
safer_gnutls_strerror(ret));
941
} else { /* dh_bits != 0 */
943
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
946
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
947
if(ret != GNUTLS_E_SUCCESS){
948
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
949
" bits): %s\n", mc->dh_bits,
950
safer_gnutls_strerror(ret));
953
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
540
gnutls_certificate_free_credentials(mc.cred);
541
gnutls_global_deinit();
542
gnutls_dh_params_deinit(mc.dh_params);
961
gnutls_certificate_free_credentials(mc->cred);
962
gnutls_dh_params_deinit(mc->dh_params);
546
static int init_gnutls_session(gnutls_session_t *session){
966
__attribute__((nonnull, warn_unused_result))
967
static int init_gnutls_session(gnutls_session_t *session,
548
970
/* GnuTLS session creation */
550
ret = gnutls_init(session, GNUTLS_SERVER);
972
ret = gnutls_init(session, (GNUTLS_SERVER
973
#if GNUTLS_VERSION_NUMBER >= 0x030506
976
#if GNUTLS_VERSION_NUMBER >= 0x030606
977
| GNUTLS_ENABLE_RAWPK
554
983
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
555
984
if(ret != GNUTLS_E_SUCCESS){
556
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
557
safer_gnutls_strerror(ret));
986
"Error in GnuTLS session initialization: %s\n",
987
safer_gnutls_strerror(ret));
563
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
993
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
565
995
gnutls_deinit(*session);
568
998
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
569
999
if(ret != GNUTLS_E_SUCCESS){
570
fprintf(stderr, "Syntax error at: %s\n", err);
571
fprintf(stderr, "GnuTLS error: %s\n",
572
safer_gnutls_strerror(ret));
1000
fprintf_plus(stderr, "Syntax error at: %s\n", err);
1001
fprintf_plus(stderr, "GnuTLS error: %s\n",
1002
safer_gnutls_strerror(ret));
573
1003
gnutls_deinit(*session);
602
1030
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
603
1031
__attribute__((unused)) const char *txt){}
1033
/* Helper function to add_local_route() and delete_local_route() */
1034
__attribute__((nonnull, warn_unused_result))
1035
static bool add_delete_local_route(const bool add,
1036
const char *address,
1037
AvahiIfIndex if_index){
1039
char helper[] = "mandos-client-iprouteadddel";
1040
char add_arg[] = "add";
1041
char delete_arg[] = "delete";
1042
char debug_flag[] = "--debug";
1043
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1044
if(pluginhelperdir == NULL){
1046
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
1047
" variable not set; cannot run helper\n");
1052
char interface[IF_NAMESIZE];
1053
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1054
perror_plus("if_indextoname");
1058
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1060
perror_plus("open(\"/dev/null\", O_RDONLY)");
1066
/* Raise privileges */
1067
errno = raise_privileges_permanently();
1069
perror_plus("Failed to raise privileges");
1070
/* _exit(EX_NOPERM); */
1076
perror_plus("setgid");
1079
/* Reset supplementary groups */
1081
ret = setgroups(0, NULL);
1083
perror_plus("setgroups");
1087
ret = dup2(devnull, STDIN_FILENO);
1089
perror_plus("dup2(devnull, STDIN_FILENO)");
1092
ret = close(devnull);
1094
perror_plus("close");
1097
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1099
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1102
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1107
if(helperdir_fd == -1){
1108
perror_plus("open");
1109
_exit(EX_UNAVAILABLE);
1111
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1113
if(helper_fd == -1){
1114
perror_plus("openat");
1115
close(helperdir_fd);
1116
_exit(EX_UNAVAILABLE);
1118
close(helperdir_fd);
1120
#pragma GCC diagnostic push
1121
#pragma GCC diagnostic ignored "-Wcast-qual"
1123
if(fexecve(helper_fd, (char *const [])
1124
{ helper, add ? add_arg : delete_arg, (char *)address,
1125
interface, debug ? debug_flag : NULL, NULL },
1128
#pragma GCC diagnostic pop
1130
perror_plus("fexecve");
1131
_exit(EXIT_FAILURE);
1135
perror_plus("fork");
1142
pret = waitpid(pid, &status, 0);
1143
if(pret == -1 and errno == EINTR and quit_now){
1144
int errno_raising = 0;
1145
if((errno = raise_privileges()) != 0){
1146
errno_raising = errno;
1147
perror_plus("Failed to raise privileges in order to"
1148
" kill helper program");
1150
if(kill(pid, SIGTERM) == -1){
1151
perror_plus("kill");
1153
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1154
perror_plus("Failed to lower privileges after killing"
1159
} while(pret == -1 and errno == EINTR);
1161
perror_plus("waitpid");
1164
if(WIFEXITED(status)){
1165
if(WEXITSTATUS(status) != 0){
1166
fprintf_plus(stderr, "Error: iprouteadddel exited"
1167
" with status %d\n", WEXITSTATUS(status));
1172
if(WIFSIGNALED(status)){
1173
fprintf_plus(stderr, "Error: iprouteadddel died by"
1174
" signal %d\n", WTERMSIG(status));
1177
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1181
__attribute__((nonnull, warn_unused_result))
1182
static bool add_local_route(const char *address,
1183
AvahiIfIndex if_index){
1185
fprintf_plus(stderr, "Adding route to %s\n", address);
1187
return add_delete_local_route(true, address, if_index);
1190
__attribute__((nonnull, warn_unused_result))
1191
static bool delete_local_route(const char *address,
1192
AvahiIfIndex if_index){
1194
fprintf_plus(stderr, "Removing route to %s\n", address);
1196
return add_delete_local_route(false, address, if_index);
605
1199
/* Called when a Mandos server is found */
606
static int start_mandos_communication(const char *ip, uint16_t port,
1200
__attribute__((nonnull, warn_unused_result))
1201
static int start_mandos_communication(const char *ip, in_port_t port,
607
1202
AvahiIfIndex if_index,
1203
int af, mandos_context *mc){
609
1204
int ret, tcp_sd = -1;
612
struct sockaddr_in in;
613
struct sockaddr_in6 in6;
1206
struct sockaddr_storage to;
615
1207
char *buffer = NULL;
616
1208
char *decrypted_buffer = NULL;
617
1209
size_t buffer_length = 0;
718
1339
if(if_indextoname((unsigned int)if_index, interface) == NULL){
719
1340
perror_plus("if_indextoname");
721
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
722
ip, interface, port);
1342
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1343
"\n", ip, interface, (uintmax_t)port);
725
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1346
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1347
ip, (uintmax_t)port);
728
1349
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
729
1350
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
732
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
735
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
739
perror_plus("inet_ntop");
741
if(strcmp(addrstr, ip) != 0){
742
fprintf(stderr, "Canonical address form: %s\n", addrstr);
753
ret = connect(tcp_sd, &to.in6, sizeof(to));
755
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
758
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
760
perror_plus("connect");
1352
ret = getnameinfo((struct sockaddr *)&to,
1353
sizeof(struct sockaddr_in6),
1354
addrstr, sizeof(addrstr), NULL, 0,
1357
ret = getnameinfo((struct sockaddr *)&to,
1358
sizeof(struct sockaddr_in),
1359
addrstr, sizeof(addrstr), NULL, 0,
1362
if(ret == EAI_SYSTEM){
1363
perror_plus("getnameinfo");
1364
} else if(ret != 0) {
1365
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1366
} else if(strcmp(addrstr, ip) != 0){
1367
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1378
ret = connect(tcp_sd, (struct sockaddr *)&to,
1379
sizeof(struct sockaddr_in6));
1381
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1382
sizeof(struct sockaddr_in));
1385
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1386
and if_index != AVAHI_IF_UNSPEC
1387
and connect_to == NULL
1388
and not route_added and
1389
((af == AF_INET6 and not
1390
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1392
or (af == AF_INET and
1393
/* Not a a IPv4LL address */
1394
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1395
& 0xFFFF0000L) != 0xA9FE0000L))){
1396
/* Work around Avahi bug - Avahi does not announce link-local
1397
addresses if it has a global address, so local hosts with
1398
*only* a link-local address (e.g. Mandos clients) cannot
1399
connect to a Mandos server announced by Avahi on a server
1400
host with a global address. Work around this by retrying
1401
with an explicit route added with the server's address.
1403
Avahi bug reference:
1404
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1405
https://bugs.debian.org/587961
1408
fprintf_plus(stderr, "Mandos server unreachable, trying"
1412
route_added = add_local_route(ip, if_index);
1418
if(errno != ECONNREFUSED or debug){
1420
perror_plus("connect");
771
1433
const char *out = mandos_protocol_version;
1088
1788
signal_received = sig;
1089
1789
int old_errno = errno;
1090
1790
/* set main loop to exit */
1091
if(mc.simple_poll != NULL){
1092
avahi_simple_poll_quit(mc.simple_poll);
1791
if(simple_poll != NULL){
1792
avahi_simple_poll_quit(simple_poll);
1094
1794
errno = old_errno;
1797
__attribute__((nonnull, warn_unused_result))
1097
1798
bool get_flags(const char *ifname, struct ifreq *ifr){
1100
1802
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1102
1805
perror_plus("socket");
1105
strcpy(ifr->ifr_name, ifname);
1809
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1810
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1106
1811
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1109
1815
perror_plus("ioctl SIOCGIFFLAGS");
1818
if((close(s) == -1) and debug){
1820
perror_plus("close");
1825
if((close(s) == -1) and debug){
1827
perror_plus("close");
1833
__attribute__((nonnull, warn_unused_result))
1116
1834
bool good_flags(const char *ifname, const struct ifreq *ifr){
1118
1836
/* Reject the loopback device */
1119
1837
if(ifr->ifr_flags & IFF_LOOPBACK){
1121
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1839
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1126
1844
/* Accept point-to-point devices only if connect_to is specified */
1127
1845
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1129
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1847
fprintf_plus(stderr, "Accepting point-to-point interface"
1848
" \"%s\"\n", ifname);
1134
1852
/* Otherwise, reject non-broadcast-capable devices */
1135
1853
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1137
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1855
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1856
" \"%s\"\n", ifname);
1142
1860
/* Reject non-ARP interfaces (including dummy interfaces) */
1143
1861
if(ifr->ifr_flags & IFF_NOARP){
1145
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n", ifname);
1863
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1150
1869
/* Accept this device */
1152
fprintf(stderr, "Interface \"%s\" is good\n", ifname);
1871
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1180
* This function determines if a directory entry in /sys/class/net
1181
* corresponds to an acceptable network device which is up.
1182
* (This function is passed to scandir(3) as a filter function.)
1184
int up_interface(const struct dirent *if_entry){
1186
char *flagname = NULL;
1187
if(if_entry->d_name[0] == '.'){
1190
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1193
perror_plus("asprintf");
1196
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1198
perror_plus("open");
1203
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1204
/* read line from flags_fd */
1205
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1206
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1207
flagstring[(size_t)to_read] = '\0';
1208
if(flagstring == NULL){
1209
perror_plus("malloc");
1214
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1217
perror_plus("read");
1231
tmpmax = strtoimax(flagstring, &tmp, 0);
1232
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1233
and not (isspace(*tmp)))
1234
or tmpmax != (ifreq_flags)tmpmax){
1236
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1237
flagstring, if_entry->d_name);
1243
ifreq_flags flags = (ifreq_flags)tmpmax;
1244
/* Reject the loopback device */
1245
if(flags & IFF_LOOPBACK){
1247
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1253
/* Reject down interfaces */
1254
if(not (flags & IFF_UP)){
1258
/* Accept point-to-point devices only if connect_to is specified */
1259
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1261
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1266
/* Otherwise, reject non-broadcast-capable devices */
1267
if(not (flags & IFF_BROADCAST)){
1269
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1274
/* Reject non-ARP interfaces (including dummy interfaces) */
1275
if(flags & IFF_NOARP){
1277
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1282
/* Accept this device */
1284
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1903
* This function determines if a network interface is up.
1905
__attribute__((nonnull, warn_unused_result))
1906
bool interface_is_up(const char *interface){
1908
if(not get_flags(interface, &ifr)){
1910
fprintf_plus(stderr, "Failed to get flags for interface "
1911
"\"%s\"\n", interface);
1916
return (bool)(ifr.ifr_flags & IFF_UP);
1920
* This function determines if a network interface is running
1922
__attribute__((nonnull, warn_unused_result))
1923
bool interface_is_running(const char *interface){
1925
if(not get_flags(interface, &ifr)){
1927
fprintf_plus(stderr, "Failed to get flags for interface "
1928
"\"%s\"\n", interface);
1933
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1936
__attribute__((nonnull, pure, warn_unused_result))
1290
1937
int notdotentries(const struct dirent *direntry){
1291
1938
/* Skip "." and ".." */
1292
1939
if(direntry->d_name[0] == '.'
1311
/* Save pointer to last character */
1312
char *end = strchr(direntry->d_name, '\0')-1;
1319
if(((direntry->d_name)[0] == '#')
1321
/* Temporary #name# */
1325
/* XXX more rules here */
1327
ret = stat(direntry->d_name, &st);
1960
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1961
"abcdefghijklmnopqrstuvwxyz"
1964
if((direntry->d_name)[sret] != '\0'){
1965
/* Contains non-allowed characters */
1967
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1973
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1330
perror_plus("Could not stat plugin");
1976
perror_plus("Could not stat hook");
1334
if(not (st.st_mode & S_ISREG)){
1980
if(not (S_ISREG(st.st_mode))){
1335
1981
/* Not a regular file */
1983
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1338
1988
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1339
1989
/* Not executable */
1991
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1997
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1345
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
2003
__attribute__((nonnull, warn_unused_result))
2004
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
2005
mandos_context *mc){
1347
2007
struct timespec now;
1348
2008
struct timespec waited_time;
1349
2009
intmax_t block_time;
1352
if(mc.current_server == NULL){
1355
"Wait until first server is found. No timeout!\n");
2012
if(mc->current_server == NULL){
2014
fprintf_plus(stderr, "Wait until first server is found."
1357
2017
ret = avahi_simple_poll_iterate(s, -1);
1360
fprintf(stderr, "Check current_server if we should run it,"
2020
fprintf_plus(stderr, "Check current_server if we should run"
1363
2023
/* the current time */
1364
2024
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1406
2067
ret = avahi_simple_poll_iterate(s, (int)block_time);
1409
if (ret > 0 or errno != EINTR) {
2070
if(ret > 0 or errno != EINTR){
1410
2071
return (ret != 1) ? ret : 0;
2077
__attribute__((nonnull))
2078
void run_network_hooks(const char *mode, const char *interface,
2080
struct dirent **direntries = NULL;
2081
if(hookdir_fd == -1){
2082
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2084
if(hookdir_fd == -1){
2085
if(errno == ENOENT){
2087
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2088
" found\n", hookdir);
2091
perror_plus("open");
2096
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2098
perror_plus("open(\"/dev/null\", O_RDONLY)");
2101
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2102
runnable_hook, alphasort);
2104
perror_plus("scandir");
2108
struct dirent *direntry;
2110
for(int i = 0; i < numhooks; i++){
2111
direntry = direntries[i];
2113
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2116
pid_t hook_pid = fork();
2119
/* Raise privileges */
2120
errno = raise_privileges_permanently();
2122
perror_plus("Failed to raise privileges");
2129
perror_plus("setgid");
2132
/* Reset supplementary groups */
2134
ret = setgroups(0, NULL);
2136
perror_plus("setgroups");
2139
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2141
perror_plus("setenv");
2144
ret = setenv("DEVICE", interface, 1);
2146
perror_plus("setenv");
2149
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2151
perror_plus("setenv");
2154
ret = setenv("MODE", mode, 1);
2156
perror_plus("setenv");
2160
ret = asprintf(&delaystring, "%f", (double)delay);
2162
perror_plus("asprintf");
2165
ret = setenv("DELAY", delaystring, 1);
2168
perror_plus("setenv");
2172
if(connect_to != NULL){
2173
ret = setenv("CONNECT", connect_to, 1);
2175
perror_plus("setenv");
2179
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2183
perror_plus("openat");
2184
_exit(EXIT_FAILURE);
2186
if(close(hookdir_fd) == -1){
2187
perror_plus("close");
2188
_exit(EXIT_FAILURE);
2190
ret = dup2(devnull, STDIN_FILENO);
2192
perror_plus("dup2(devnull, STDIN_FILENO)");
2195
ret = close(devnull);
2197
perror_plus("close");
2200
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2202
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2205
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2207
perror_plus("fexecve");
2208
_exit(EXIT_FAILURE);
2212
perror_plus("fork");
2217
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2218
perror_plus("waitpid");
2222
if(WIFEXITED(status)){
2223
if(WEXITSTATUS(status) != 0){
2224
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2225
" with status %d\n", direntry->d_name,
2226
WEXITSTATUS(status));
2230
} else if(WIFSIGNALED(status)){
2231
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2232
" signal %d\n", direntry->d_name,
2237
fprintf_plus(stderr, "Warning: network hook \"%s\""
2238
" crashed\n", direntry->d_name);
2244
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2250
if(close(hookdir_fd) == -1){
2251
perror_plus("close");
2258
__attribute__((nonnull, warn_unused_result))
2259
int bring_up_interface(const char *const interface,
2261
int old_errno = errno;
2263
struct ifreq network;
2264
unsigned int if_index = if_nametoindex(interface);
2266
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2276
if(not interface_is_up(interface)){
2278
int ioctl_errno = 0;
2279
if(not get_flags(interface, &network)){
2281
fprintf_plus(stderr, "Failed to get flags for interface "
2282
"\"%s\"\n", interface);
2286
network.ifr_flags |= IFF_UP; /* set flag */
2288
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2291
perror_plus("socket");
2299
perror_plus("close");
2306
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2310
/* Raise privileges */
2311
ret_errno = raise_privileges();
2314
perror_plus("Failed to raise privileges");
2319
bool restore_loglevel = false;
2321
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2322
messages about the network interface to mess up the prompt */
2323
ret_linux = klogctl(8, NULL, 5);
2324
if(ret_linux == -1){
2325
perror_plus("klogctl");
2327
restore_loglevel = true;
2330
#endif /* __linux__ */
2331
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2332
ioctl_errno = errno;
2334
if(restore_loglevel){
2335
ret_linux = klogctl(7, NULL, 0);
2336
if(ret_linux == -1){
2337
perror_plus("klogctl");
2340
#endif /* __linux__ */
2342
/* If raise_privileges() succeeded above */
2344
/* Lower privileges */
2345
ret_errno = lower_privileges();
2348
perror_plus("Failed to lower privileges");
2352
/* Close the socket */
2355
perror_plus("close");
2358
if(ret_setflags == -1){
2359
errno = ioctl_errno;
2360
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2365
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2369
/* Sleep checking until interface is running.
2370
Check every 0.25s, up to total time of delay */
2371
for(int i = 0; i < delay * 4; i++){
2372
if(interface_is_running(interface)){
2375
struct timespec sleeptime = { .tv_nsec = 250000000 };
2376
ret = nanosleep(&sleeptime, NULL);
2377
if(ret == -1 and errno != EINTR){
2378
perror_plus("nanosleep");
2386
__attribute__((nonnull, warn_unused_result))
2387
int take_down_interface(const char *const interface){
2388
int old_errno = errno;
2389
struct ifreq network;
2390
unsigned int if_index = if_nametoindex(interface);
2392
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2396
if(interface_is_up(interface)){
2398
int ioctl_errno = 0;
2399
if(not get_flags(interface, &network) and debug){
2401
fprintf_plus(stderr, "Failed to get flags for interface "
2402
"\"%s\"\n", interface);
2406
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2408
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2411
perror_plus("socket");
2417
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2421
/* Raise privileges */
2422
ret_errno = raise_privileges();
2425
perror_plus("Failed to raise privileges");
2428
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2429
ioctl_errno = errno;
2431
/* If raise_privileges() succeeded above */
2433
/* Lower privileges */
2434
ret_errno = lower_privileges();
2437
perror_plus("Failed to lower privileges");
2441
/* Close the socket */
2442
int ret = close(sd);
2444
perror_plus("close");
2447
if(ret_setflags == -1){
2448
errno = ioctl_errno;
2449
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2454
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1416
2462
int main(int argc, char *argv[]){
2463
mandos_context mc = { .server = NULL, .dh_bits = 0,
2464
#if GNUTLS_VERSION_NUMBER >= 0x030606
2465
.priority = "SECURE128:!CTYPE-X.509"
2466
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2468
#elif GNUTLS_VERSION_NUMBER < 0x030600
2469
.priority = "SECURE256:!CTYPE-X.509"
2470
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2472
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2474
.current_server = NULL, .interfaces = NULL,
2475
.interfaces_size = 0 };
1417
2476
AvahiSServiceBrowser *sb = NULL;
1420
2479
intmax_t tmpmax;
1422
2481
int exitcode = EXIT_SUCCESS;
1423
const char *interface = "";
1424
struct ifreq network;
1426
bool take_down_interface = false;
1429
char tempdir[] = "/tmp/mandosXXXXXX";
1430
bool tempdir_created = false;
2482
char *interfaces_to_take_down = NULL;
2483
size_t interfaces_to_take_down_size = 0;
2484
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2485
char old_tempdir[] = "/tmp/mandosXXXXXX";
2486
char *tempdir = NULL;
1431
2487
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1432
2488
const char *seckey = PATHDIR "/" SECKEY;
1433
2489
const char *pubkey = PATHDIR "/" PUBKEY;
2490
#if GNUTLS_VERSION_NUMBER >= 0x030606
2491
const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;
2492
const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;
2494
const char *dh_params_file = NULL;
2495
char *interfaces_hooks = NULL;
1435
2497
bool gnutls_initialized = false;
1436
2498
bool gpgme_initialized = false;
1603
2710
/* Work around Debian bug #633582:
1604
<http://bugs.debian.org/633582> */
1607
/* Re-raise priviliges */
1611
perror_plus("seteuid");
1614
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1615
int seckey_fd = open(seckey, O_RDONLY);
1616
if(seckey_fd == -1){
1617
perror_plus("open");
1619
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1621
perror_plus("fstat");
1623
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1624
ret = fchown(seckey_fd, uid, gid);
1626
perror_plus("fchown");
1630
TEMP_FAILURE_RETRY(close(seckey_fd));
1634
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1635
int pubkey_fd = open(pubkey, O_RDONLY);
1636
if(pubkey_fd == -1){
1637
perror_plus("open");
1639
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1641
perror_plus("fstat");
1643
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1644
ret = fchown(pubkey_fd, uid, gid);
1646
perror_plus("fchown");
1650
TEMP_FAILURE_RETRY(close(pubkey_fd));
1654
/* Lower privileges */
1658
perror_plus("seteuid");
1662
/* Find network hooks and run them */
1664
struct dirent **direntries;
1665
struct dirent *direntry;
1666
int numhooks = scandir(HOOKDIR, &direntries, runnable_hook,
1668
int devnull = open("/dev/null", O_RDONLY);
1669
for(int i = 0; i < numhooks; i++){
1670
direntry = direntries[0];
1671
char *fullname = NULL;
1672
ret = asprintf(&fullname, "%s/%s", tempdir,
1675
perror_plus("asprintf");
1678
pid_t hook_pid = fork();
1681
dup2(devnull, STDIN_FILENO);
1683
dup2(STDERR_FILENO, STDOUT_FILENO);
1684
setenv("DEVICE", interface, 1);
1685
setenv("VERBOSE", debug ? "1" : "0", 1);
1686
setenv("MODE", "start", 1);
1687
/* setenv( XXX more here */
1688
ret = execl(fullname, direntry->d_name, "start");
1689
perror_plus("execl");
2711
<https://bugs.debian.org/633582> */
2713
/* Re-raise privileges */
2714
ret = raise_privileges();
2717
perror_plus("Failed to raise privileges");
2721
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2722
int seckey_fd = open(seckey, O_RDONLY);
2723
if(seckey_fd == -1){
2724
perror_plus("open");
2726
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2728
perror_plus("fstat");
2730
if(S_ISREG(st.st_mode)
2731
and st.st_uid == 0 and st.st_gid == 0){
2732
ret = fchown(seckey_fd, uid, gid);
2734
perror_plus("fchown");
2742
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2743
int pubkey_fd = open(pubkey, O_RDONLY);
2744
if(pubkey_fd == -1){
2745
perror_plus("open");
2747
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2749
perror_plus("fstat");
2751
if(S_ISREG(st.st_mode)
2752
and st.st_uid == 0 and st.st_gid == 0){
2753
ret = fchown(pubkey_fd, uid, gid);
2755
perror_plus("fchown");
2763
if(dh_params_file != NULL
2764
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2765
int dhparams_fd = open(dh_params_file, O_RDONLY);
2766
if(dhparams_fd == -1){
2767
perror_plus("open");
2769
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2771
perror_plus("fstat");
2773
if(S_ISREG(st.st_mode)
2774
and st.st_uid == 0 and st.st_gid == 0){
2775
ret = fchown(dhparams_fd, uid, gid);
2777
perror_plus("fchown");
2785
/* Lower privileges */
2786
ret = lower_privileges();
2789
perror_plus("Failed to lower privileges");
2794
/* Remove invalid interface names (except "none") */
2796
char *interface = NULL;
2797
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2799
if(strcmp(interface, "none") != 0
2800
and if_nametoindex(interface) == 0){
2801
if(interface[0] != '\0'){
2802
fprintf_plus(stderr, "Not using nonexisting interface"
2803
" \"%s\"\n", interface);
2805
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2811
/* Run network hooks */
2813
if(mc.interfaces != NULL){
2814
interfaces_hooks = malloc(mc.interfaces_size);
2815
if(interfaces_hooks == NULL){
2816
perror_plus("malloc");
2819
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2820
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2822
run_network_hooks("start", interfaces_hooks != NULL ?
2823
interfaces_hooks : "", delay);
1700
2827
avahi_set_log_function(empty_log);
1703
if(interface[0] == '\0'){
1704
struct dirent **direntries;
1705
ret = scandir(sys_class_net, &direntries, good_interface,
1708
/* Pick the first good interface */
1709
interface = strdup(direntries[0]->d_name);
1711
fprintf(stderr, "Using interface \"%s\"\n", interface);
1713
if(interface == NULL){
1714
perror_plus("malloc");
1716
exitcode = EXIT_FAILURE;
1722
fprintf(stderr, "Could not find a network interface\n");
1723
exitcode = EXIT_FAILURE;
1728
2830
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1729
2831
from the signal handler */
1730
2832
/* Initialize the pseudo-RNG for Avahi */
1731
2833
srand((unsigned int) time(NULL));
1732
mc.simple_poll = avahi_simple_poll_new();
1733
if(mc.simple_poll == NULL){
1734
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2834
simple_poll = avahi_simple_poll_new();
2835
if(simple_poll == NULL){
2836
fprintf_plus(stderr,
2837
"Avahi: Failed to create simple poll object.\n");
1735
2838
exitcode = EX_UNAVAILABLE;
1802
/* If the interface is down, bring it up */
1803
if(strcmp(interface, "none") != 0){
1804
if_index = (AvahiIfIndex) if_nametoindex(interface);
1806
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1807
exitcode = EX_UNAVAILABLE;
1815
/* Re-raise priviliges */
1819
perror_plus("seteuid");
1823
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1824
messages about the network interface to mess up the prompt */
1825
ret = klogctl(8, NULL, 5);
1826
bool restore_loglevel = true;
1828
restore_loglevel = false;
1829
perror_plus("klogctl");
1831
#endif /* __linux__ */
1833
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1835
perror_plus("socket");
1836
exitcode = EX_OSERR;
1838
if(restore_loglevel){
1839
ret = klogctl(7, NULL, 0);
1841
perror_plus("klogctl");
1844
#endif /* __linux__ */
1845
/* Lower privileges */
1849
perror_plus("seteuid");
1853
strcpy(network.ifr_name, interface);
1854
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1856
perror_plus("ioctl SIOCGIFFLAGS");
1858
if(restore_loglevel){
1859
ret = klogctl(7, NULL, 0);
1861
perror_plus("klogctl");
1864
#endif /* __linux__ */
1865
exitcode = EX_OSERR;
1866
/* Lower privileges */
1870
perror_plus("seteuid");
1874
if((network.ifr_flags & IFF_UP) == 0){
1875
network.ifr_flags |= IFF_UP;
1876
take_down_interface = true;
1877
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1879
take_down_interface = false;
1880
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1881
exitcode = EX_OSERR;
1883
if(restore_loglevel){
1884
ret = klogctl(7, NULL, 0);
1886
perror_plus("klogctl");
2905
/* If no interfaces were specified, make a list */
2906
if(mc.interfaces == NULL){
2907
struct dirent **direntries = NULL;
2908
/* Look for any good interfaces */
2909
ret = scandir(sys_class_net, &direntries, good_interface,
2912
/* Add all found interfaces to interfaces list */
2913
for(int i = 0; i < ret; ++i){
2914
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2915
direntries[i]->d_name);
2918
perror_plus("argz_add");
2919
free(direntries[i]);
2923
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2924
direntries[i]->d_name);
2926
free(direntries[i]);
2933
fprintf_plus(stderr, "Could not find a network interface\n");
2934
exitcode = EXIT_FAILURE;
2939
/* Bring up interfaces which are down, and remove any "none"s */
2941
char *interface = NULL;
2942
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2944
/* If interface name is "none", stop bringing up interfaces.
2945
Also remove all instances of "none" from the list */
2946
if(strcmp(interface, "none") == 0){
2947
argz_delete(&mc.interfaces, &mc.interfaces_size,
2950
while((interface = argz_next(mc.interfaces,
2951
mc.interfaces_size, interface))){
2952
if(strcmp(interface, "none") == 0){
2953
argz_delete(&mc.interfaces, &mc.interfaces_size,
1889
#endif /* __linux__ */
1890
/* Lower privileges */
1894
perror_plus("seteuid");
1899
/* Sleep checking until interface is running.
1900
Check every 0.25s, up to total time of delay */
1901
for(int i=0; i < delay * 4; i++){
1902
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1904
perror_plus("ioctl SIOCGIFFLAGS");
1905
} else if(network.ifr_flags & IFF_RUNNING){
1908
struct timespec sleeptime = { .tv_nsec = 250000000 };
1909
ret = nanosleep(&sleeptime, NULL);
1910
if(ret == -1 and errno != EINTR){
1911
perror_plus("nanosleep");
1914
if(not take_down_interface){
1915
/* We won't need the socket anymore */
1916
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1918
perror_plus("close");
1922
if(restore_loglevel){
1923
/* Restores kernel loglevel to default */
1924
ret = klogctl(7, NULL, 0);
1926
perror_plus("klogctl");
1929
#endif /* __linux__ */
1930
/* Lower privileges */
1932
if(take_down_interface){
1933
/* Lower privileges */
1936
perror_plus("seteuid");
1939
/* Lower privileges permanently */
1942
perror_plus("setuid");
2960
bool interface_was_up = interface_is_up(interface);
2961
errno = bring_up_interface(interface, delay);
2962
if(not interface_was_up){
2964
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2965
" %s\n", interface, strerror(errno));
2967
errno = argz_add(&interfaces_to_take_down,
2968
&interfaces_to_take_down_size,
2971
perror_plus("argz_add");
2976
if(debug and (interfaces_to_take_down == NULL)){
2977
fprintf_plus(stderr, "No interfaces were brought up\n");
2981
/* If we only got one interface, explicitly use only that one */
2982
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2984
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2987
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1951
ret = init_gnutls_global(pubkey, seckey);
2994
#if GNUTLS_VERSION_NUMBER >= 0x030606
2995
ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);
2996
#elif GNUTLS_VERSION_NUMBER < 0x030600
2997
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2999
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
1953
fprintf(stderr, "init_gnutls_global failed\n");
3002
fprintf_plus(stderr, "init_gnutls_global failed\n");
1954
3003
exitcode = EX_UNAVAILABLE;
2103
3162
/* Run the main loop */
2106
fprintf(stderr, "Starting Avahi loop search\n");
3165
fprintf_plus(stderr, "Starting Avahi loop search\n");
2109
ret = avahi_loop_with_timeout(mc.simple_poll,
2110
(int)(retry_interval * 1000));
3168
ret = avahi_loop_with_timeout(simple_poll,
3169
(int)(retry_interval * 1000), &mc);
2112
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
2113
(ret == 0) ? "successfully" : "with error");
3171
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
3172
(ret == 0) ? "successfully" : "with error");
2119
fprintf(stderr, "%s exiting\n", argv[0]);
3178
if(signal_received){
3179
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
3180
argv[0], signal_received,
3181
strsignal(signal_received));
3183
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2122
3187
/* Cleanup things */
3188
free(mc.interfaces);
2124
3191
avahi_s_service_browser_free(sb);
2126
3193
if(mc.server != NULL)
2127
3194
avahi_server_free(mc.server);
2129
if(mc.simple_poll != NULL)
2130
avahi_simple_poll_free(mc.simple_poll);
3196
if(simple_poll != NULL)
3197
avahi_simple_poll_free(simple_poll);
2132
3199
if(gnutls_initialized){
2133
3200
gnutls_certificate_free_credentials(mc.cred);
2134
gnutls_global_deinit();
2135
3201
gnutls_dh_params_deinit(mc.dh_params);
2138
3204
if(gpgme_initialized){
2139
3205
gpgme_release(mc.ctx);
2142
3208
/* Cleans up the circular linked list of Mandos servers the client
2144
3210
if(mc.current_server != NULL){
2145
3211
mc.current_server->prev->next = NULL;
2146
3212
while(mc.current_server != NULL){
2147
3213
server *next = mc.current_server->next;
3215
#pragma GCC diagnostic push
3216
#pragma GCC diagnostic ignored "-Wcast-qual"
3218
free((char *)(mc.current_server->ip));
3220
#pragma GCC diagnostic pop
2148
3222
free(mc.current_server);
2149
3223
mc.current_server = next;
2153
/* XXX run network hooks "stop" here */
2155
/* Take down the network interface */
2156
if(take_down_interface){
2157
/* Re-raise priviliges */
2161
perror_plus("seteuid");
2164
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2166
perror_plus("ioctl SIOCGIFFLAGS");
2167
} else if(network.ifr_flags & IFF_UP) {
2168
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2169
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2171
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2174
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2176
perror_plus("close");
2178
/* Lower privileges permanently */
2182
perror_plus("setuid");
3227
/* Re-raise privileges */
3229
ret = raise_privileges();
3232
perror_plus("Failed to raise privileges");
3235
/* Run network hooks */
3236
run_network_hooks("stop", interfaces_hooks != NULL ?
3237
interfaces_hooks : "", delay);
3239
/* Take down the network interfaces which were brought up */
3241
char *interface = NULL;
3242
while((interface = argz_next(interfaces_to_take_down,
3243
interfaces_to_take_down_size,
3245
ret = take_down_interface(interface);
3248
perror_plus("Failed to take down interface");
3251
if(debug and (interfaces_to_take_down == NULL)){
3252
fprintf_plus(stderr, "No interfaces needed to be taken"
3258
ret = lower_privileges_permanently();
3261
perror_plus("Failed to lower privileges permanently");
3265
free(interfaces_to_take_down);
3266
free(interfaces_hooks);
3268
void clean_dir_at(int base, const char * const dirname,
3270
struct dirent **direntries = NULL;
3272
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3278
perror_plus("open");
3281
int numentries = scandirat(dir_fd, ".", &direntries,
3282
notdotentries, alphasort);
3283
if(numentries >= 0){
3284
for(int i = 0; i < numentries; i++){
3286
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3287
dirname, direntries[i]->d_name);
3289
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3291
if(errno == EISDIR){
3292
dret = unlinkat(dir_fd, direntries[i]->d_name,
3295
if((dret == -1) and (errno == ENOTEMPTY)
3296
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3297
== 0) and (level == 0)){
3298
/* Recurse only in this special case */
3299
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3302
if((dret == -1) and (errno != ENOENT)){
3303
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3304
direntries[i]->d_name, strerror(errno));
3307
free(direntries[i]);
3310
/* need to clean even if 0 because man page doesn't specify */
3312
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3313
if(dret == -1 and errno != ENOENT){
3314
perror_plus("rmdir");
3317
perror_plus("scandirat");
2187
3322
/* Removes the GPGME temp directory and all files inside */
2188
if(tempdir_created){
2189
struct dirent **direntries = NULL;
2190
struct dirent *direntry = NULL;
2191
int numentries = scandir(tempdir, &direntries, notdotentries,
2193
if (numentries > 0){
2194
for(int i = 0; i < numentries; i++){
2195
direntry = direntries[i];
2196
char *fullname = NULL;
2197
ret = asprintf(&fullname, "%s/%s", tempdir,
2200
perror_plus("asprintf");
2203
ret = remove(fullname);
2205
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2212
/* need to clean even if 0 because man page doesn't specify */
2214
if (numentries == -1){
2215
perror_plus("scandir");
2217
ret = rmdir(tempdir);
2218
if(ret == -1 and errno != ENOENT){
2219
perror_plus("rmdir");
3323
if(tempdir != NULL){
3324
clean_dir_at(-1, tempdir, 0);