9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008-2011 Teddy Hogeborn
13
* Copyright © 2008-2011 Björn Påhlsson
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
20
* This program is distributed in the hope that it will be useful, but
12
* Copyright © 2008-2018 Teddy Hogeborn
13
* Copyright © 2008-2018 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
21
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
25
* General Public License for more details.
25
27
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
* Contact the authors at <mandos@recompile.se>.
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
37
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 */
46
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
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,
53
55
sockaddr_in6, PF_INET6,
54
56
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open() */
58
#include <sys/stat.h> /* open(), S_ISREG */
57
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,
68
EAI_SYSTEM, ENETUNREACH,
69
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,
152
172
const char *priority;
154
174
server *current_server;
176
size_t interfaces_size;
155
177
} mandos_context;
157
/* global context so signal handler can reach it*/
158
mandos_context mc = { .simple_poll = NULL, .server = NULL,
159
.dh_bits = 1024, .priority = "SECURE256"
160
":!CTYPE-X.509:+CTYPE-OPENPGP",
161
.current_server = NULL };
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
163
182
sig_atomic_t quit_now = 0;
164
183
int signal_received = 0;
166
185
/* Function to use when printing errors */
167
186
void perror_plus(const char *print_text){
168
188
fprintf(stderr, "Mandos plugin %s: ",
169
189
program_invocation_short_name);
170
191
perror(print_text);
194
__attribute__((format (gnu_printf, 2, 3), nonnull))
195
int fprintf_plus(FILE *stream, const char *format, ...){
197
va_start (ap, format);
199
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
200
program_invocation_short_name));
201
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
174
205
* Make additional room in "buffer" for at least BUFFER_SIZE more
175
206
* bytes. "buffer_capacity" is how much is currently allocated,
176
207
* "buffer_length" is how much is already used.
209
__attribute__((nonnull, warn_unused_result))
178
210
size_t incbuffer(char **buffer, size_t buffer_length,
179
size_t buffer_capacity){
211
size_t buffer_capacity){
180
212
if(buffer_length + BUFFER_SIZE > buffer_capacity){
181
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
185
222
buffer_capacity += BUFFER_SIZE;
187
224
return buffer_capacity;
190
int add_server(const char *ip, uint16_t port,
191
AvahiIfIndex if_index,
227
/* Add server to set of servers to retry periodically */
228
__attribute__((nonnull, warn_unused_result))
229
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
230
int af, server **current_server){
194
232
server *new_server = malloc(sizeof(server));
195
233
if(new_server == NULL){
196
234
perror_plus("malloc");
199
237
*new_server = (server){ .ip = strdup(ip),
201
.if_index = if_index,
239
.if_index = if_index,
203
241
if(new_server->ip == NULL){
204
242
perror_plus("strdup");
207
/* unique case of first server */
208
if (mc.current_server == NULL){
246
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
248
perror_plus("clock_gettime");
250
#pragma GCC diagnostic push
251
#pragma GCC diagnostic ignored "-Wcast-qual"
253
free((char *)(new_server->ip));
255
#pragma GCC diagnostic pop
260
/* Special case of first server */
261
if(*current_server == NULL){
209
262
new_server->next = new_server;
210
263
new_server->prev = new_server;
211
mc.current_server = new_server;
212
/* Placing the new server last in the list */
264
*current_server = new_server;
214
new_server->next = mc.current_server;
215
new_server->prev = mc.current_server->prev;
266
/* Place the new server last in the list */
267
new_server->next = *current_server;
268
new_server->prev = (*current_server)->prev;
216
269
new_server->prev->next = new_server;
217
mc.current_server->prev = new_server;
219
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
221
perror_plus("clock_gettime");
270
(*current_server)->prev = new_server;
228
276
* Initialize GPGME.
230
static bool init_gpgme(const char *seckey,
231
const char *pubkey, const char *tempdir){
278
__attribute__((nonnull, warn_unused_result))
279
static bool init_gpgme(const char * const seckey,
280
const char * const pubkey,
281
const char * const tempdir,
232
283
gpgme_error_t rc;
233
284
gpgme_engine_info_t engine_info;
237
287
* Helper function to insert pub and seckey to the engine keyring.
239
bool import_key(const char *filename){
289
bool import_key(const char * const filename){
242
292
gpgme_data_t pgp_data;
250
300
rc = gpgme_data_new_from_fd(&pgp_data, fd);
251
301
if(rc != GPG_ERR_NO_ERROR){
252
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
253
gpgme_strsource(rc), gpgme_strerror(rc));
302
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
303
gpgme_strsource(rc), gpgme_strerror(rc));
257
rc = gpgme_op_import(mc.ctx, pgp_data);
307
rc = gpgme_op_import(mc->ctx, pgp_data);
258
308
if(rc != GPG_ERR_NO_ERROR){
259
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
260
gpgme_strsource(rc), gpgme_strerror(rc));
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
314
gpgme_import_result_t import_result
315
= gpgme_op_import_result(mc->ctx);
316
if((import_result->imported < 1
317
or import_result->not_imported > 0)
318
and import_result->unchanged == 0){
319
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
321
"The total number of considered keys: %d\n",
322
import_result->considered);
324
"The number of keys without user ID: %d\n",
325
import_result->no_user_id);
327
"The total number of imported keys: %d\n",
328
import_result->imported);
329
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
330
import_result->imported_rsa);
331
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
332
import_result->unchanged);
333
fprintf_plus(stderr, "The number of new user IDs: %d\n",
334
import_result->new_user_ids);
335
fprintf_plus(stderr, "The number of new sub keys: %d\n",
336
import_result->new_sub_keys);
337
fprintf_plus(stderr, "The number of new signatures: %d\n",
338
import_result->new_signatures);
339
fprintf_plus(stderr, "The number of new revocations: %d\n",
340
import_result->new_revocations);
342
"The total number of secret keys read: %d\n",
343
import_result->secret_read);
345
"The number of imported secret keys: %d\n",
346
import_result->secret_imported);
348
"The number of unchanged secret keys: %d\n",
349
import_result->secret_unchanged);
350
fprintf_plus(stderr, "The number of keys not imported: %d\n",
351
import_result->not_imported);
352
for(gpgme_import_status_t import_status
353
= import_result->imports;
354
import_status != NULL;
355
import_status = import_status->next){
356
fprintf_plus(stderr, "Import status for key: %s\n",
358
if(import_status->result != GPG_ERR_NO_ERROR){
359
fprintf_plus(stderr, "Import result: %s: %s\n",
360
gpgme_strsource(import_status->result),
361
gpgme_strerror(import_status->result));
363
fprintf_plus(stderr, "Key status:\n");
365
import_status->status & GPGME_IMPORT_NEW
366
? "The key was new.\n"
367
: "The key was not new.\n");
369
import_status->status & GPGME_IMPORT_UID
370
? "The key contained new user IDs.\n"
371
: "The key did not contain new user IDs.\n");
373
import_status->status & GPGME_IMPORT_SIG
374
? "The key contained new signatures.\n"
375
: "The key did not contain new signatures.\n");
377
import_status->status & GPGME_IMPORT_SUBKEY
378
? "The key contained new sub keys.\n"
379
: "The key did not contain new sub keys.\n");
381
import_status->status & GPGME_IMPORT_SECRET
382
? "The key contained a secret key.\n"
383
: "The key did not contain a secret key.\n");
264
ret = (int)TEMP_FAILURE_RETRY(close(fd));
266
391
perror_plus("close");
331
459
ssize_t plaintext_length = 0;
334
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
462
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
337
465
/* Create new GPGME data buffer from memory cryptotext */
338
466
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
340
468
if(rc != GPG_ERR_NO_ERROR){
341
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
342
gpgme_strsource(rc), gpgme_strerror(rc));
469
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
470
gpgme_strsource(rc), gpgme_strerror(rc));
346
474
/* Create new empty GPGME data buffer for the plaintext */
347
475
rc = gpgme_data_new(&dh_plain);
348
476
if(rc != GPG_ERR_NO_ERROR){
349
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
350
gpgme_strsource(rc), gpgme_strerror(rc));
477
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
478
gpgme_strsource(rc), gpgme_strerror(rc));
351
479
gpgme_data_release(dh_crypto);
355
483
/* Decrypt data from the cryptotext data buffer to the plaintext
357
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
485
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
358
486
if(rc != GPG_ERR_NO_ERROR){
359
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
360
gpgme_strsource(rc), gpgme_strerror(rc));
487
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
488
gpgme_strsource(rc), gpgme_strerror(rc));
361
489
plaintext_length = -1;
363
491
gpgme_decrypt_result_t result;
364
result = gpgme_op_decrypt_result(mc.ctx);
492
result = gpgme_op_decrypt_result(mc->ctx);
365
493
if(result == NULL){
366
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
494
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
368
fprintf(stderr, "Unsupported algorithm: %s\n",
369
result->unsupported_algorithm);
370
fprintf(stderr, "Wrong key usage: %u\n",
371
result->wrong_key_usage);
496
if(result->unsupported_algorithm != NULL) {
497
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
498
result->unsupported_algorithm);
500
fprintf_plus(stderr, "Wrong key usage: %s\n",
501
result->wrong_key_usage ? "Yes" : "No");
372
502
if(result->file_name != NULL){
373
fprintf(stderr, "File name: %s\n", result->file_name);
503
fprintf_plus(stderr, "File name: %s\n", result->file_name);
375
505
gpgme_recipient_t recipient;
376
506
recipient = result->recipients;
377
507
while(recipient != NULL){
378
fprintf(stderr, "Public key algorithm: %s\n",
379
gpgme_pubkey_algo_name(recipient->pubkey_algo));
380
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
381
fprintf(stderr, "Secret key available: %s\n",
382
recipient->status == GPG_ERR_NO_SECKEY
508
fprintf_plus(stderr, "Public key algorithm: %s\n",
509
gpgme_pubkey_algo_name
510
(recipient->pubkey_algo));
511
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
512
fprintf_plus(stderr, "Secret key available: %s\n",
513
recipient->status == GPG_ERR_NO_SECKEY
384
515
recipient = recipient->next;
443
574
return plaintext_length;
446
static const char * safer_gnutls_strerror(int value){
447
const char *ret = gnutls_strerror(value); /* Spurious warning from
448
-Wunreachable-code */
577
__attribute__((warn_unused_result, const))
578
static const char *safe_string(const char *str){
584
__attribute__((warn_unused_result))
585
static const char *safer_gnutls_strerror(int value){
586
const char *ret = gnutls_strerror(value);
587
return safe_string(ret);
454
590
/* GnuTLS log function callback */
591
__attribute__((nonnull))
455
592
static void debuggnutls(__attribute__((unused)) int level,
456
593
const char* string){
457
fprintf(stderr, "GnuTLS: %s", string);
594
fprintf_plus(stderr, "GnuTLS: %s", string);
597
__attribute__((nonnull(1, 2, 4), warn_unused_result))
460
598
static int init_gnutls_global(const char *pubkeyfilename,
461
const char *seckeyfilename){
599
const char *seckeyfilename,
600
const char *dhparamsfilename,
465
fprintf(stderr, "Initializing GnuTLS\n");
468
ret = gnutls_global_init();
469
if(ret != GNUTLS_E_SUCCESS){
470
fprintf(stderr, "GnuTLS global_init: %s\n",
471
safer_gnutls_strerror(ret));
606
fprintf_plus(stderr, "Initializing GnuTLS\n");
483
617
/* OpenPGP credentials */
484
ret = gnutls_certificate_allocate_credentials(&mc.cred);
618
ret = gnutls_certificate_allocate_credentials(&mc->cred);
485
619
if(ret != GNUTLS_E_SUCCESS){
486
fprintf(stderr, "GnuTLS memory error: %s\n",
487
safer_gnutls_strerror(ret));
488
gnutls_global_deinit();
620
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
621
safer_gnutls_strerror(ret));
493
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
494
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
626
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
627
" secret key %s as GnuTLS credentials\n",
498
632
ret = gnutls_certificate_set_openpgp_key_file
499
(mc.cred, pubkeyfilename, seckeyfilename,
633
(mc->cred, pubkeyfilename, seckeyfilename,
500
634
GNUTLS_OPENPGP_FMT_BASE64);
501
635
if(ret != GNUTLS_E_SUCCESS){
503
"Error[%d] while reading the OpenPGP key pair ('%s',"
504
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
505
fprintf(stderr, "The GnuTLS error is: %s\n",
506
safer_gnutls_strerror(ret));
637
"Error[%d] while reading the OpenPGP key pair ('%s',"
638
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
639
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
640
safer_gnutls_strerror(ret));
510
644
/* GnuTLS server initialization */
511
ret = gnutls_dh_params_init(&mc.dh_params);
512
if(ret != GNUTLS_E_SUCCESS){
513
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
514
" %s\n", safer_gnutls_strerror(ret));
517
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
518
if(ret != GNUTLS_E_SUCCESS){
519
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
520
safer_gnutls_strerror(ret));
524
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
645
ret = gnutls_dh_params_init(&mc->dh_params);
646
if(ret != GNUTLS_E_SUCCESS){
647
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
648
" initialization: %s\n",
649
safer_gnutls_strerror(ret));
652
/* If a Diffie-Hellman parameters file was given, try to use it */
653
if(dhparamsfilename != NULL){
654
gnutls_datum_t params = { .data = NULL, .size = 0 };
656
int dhpfile = open(dhparamsfilename, O_RDONLY);
659
dhparamsfilename = NULL;
662
size_t params_capacity = 0;
664
params_capacity = incbuffer((char **)¶ms.data,
666
(size_t)params_capacity);
667
if(params_capacity == 0){
668
perror_plus("incbuffer");
671
dhparamsfilename = NULL;
674
ssize_t bytes_read = read(dhpfile,
675
params.data + params.size,
681
/* check bytes_read for failure */
686
dhparamsfilename = NULL;
689
params.size += (unsigned int)bytes_read;
691
ret = close(dhpfile);
693
perror_plus("close");
695
if(params.data == NULL){
696
dhparamsfilename = NULL;
698
if(dhparamsfilename == NULL){
701
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
702
GNUTLS_X509_FMT_PEM);
703
if(ret != GNUTLS_E_SUCCESS){
704
fprintf_plus(stderr, "Failed to parse DH parameters in file"
705
" \"%s\": %s\n", dhparamsfilename,
706
safer_gnutls_strerror(ret));
707
dhparamsfilename = NULL;
712
if(dhparamsfilename == NULL){
713
if(mc->dh_bits == 0){
714
/* Find out the optimal number of DH bits */
715
/* Try to read the private key file */
716
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
718
int secfile = open(seckeyfilename, O_RDONLY);
723
size_t buffer_capacity = 0;
725
buffer_capacity = incbuffer((char **)&buffer.data,
727
(size_t)buffer_capacity);
728
if(buffer_capacity == 0){
729
perror_plus("incbuffer");
734
ssize_t bytes_read = read(secfile,
735
buffer.data + buffer.size,
741
/* check bytes_read for failure */
748
buffer.size += (unsigned int)bytes_read;
752
/* If successful, use buffer to parse private key */
753
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
754
if(buffer.data != NULL){
756
gnutls_openpgp_privkey_t privkey = NULL;
757
ret = gnutls_openpgp_privkey_init(&privkey);
758
if(ret != GNUTLS_E_SUCCESS){
759
fprintf_plus(stderr, "Error initializing OpenPGP key"
761
safer_gnutls_strerror(ret));
765
ret = gnutls_openpgp_privkey_import
766
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
767
if(ret != GNUTLS_E_SUCCESS){
768
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
769
safer_gnutls_strerror(ret));
775
/* Use private key to suggest an appropriate
777
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
778
gnutls_openpgp_privkey_deinit(privkey);
780
fprintf_plus(stderr, "This OpenPGP key implies using"
781
" a GnuTLS security parameter \"%s\".\n",
782
safe_string(gnutls_sec_param_get_name
788
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
789
/* Err on the side of caution */
790
sec_param = GNUTLS_SEC_PARAM_ULTRA;
792
fprintf_plus(stderr, "Falling back to security parameter"
794
safe_string(gnutls_sec_param_get_name
799
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
803
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
804
" implies %u DH bits; using that.\n",
805
safe_string(gnutls_sec_param_get_name
810
fprintf_plus(stderr, "Failed to get implied number of DH"
811
" bits for security parameter \"%s\"): %s\n",
812
safe_string(gnutls_sec_param_get_name
814
safer_gnutls_strerror(ret));
818
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
821
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
822
if(ret != GNUTLS_E_SUCCESS){
823
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
824
" bits): %s\n", mc->dh_bits,
825
safer_gnutls_strerror(ret));
829
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
530
gnutls_certificate_free_credentials(mc.cred);
531
gnutls_global_deinit();
532
gnutls_dh_params_deinit(mc.dh_params);
835
gnutls_certificate_free_credentials(mc->cred);
836
gnutls_dh_params_deinit(mc->dh_params);
536
static int init_gnutls_session(gnutls_session_t *session){
840
__attribute__((nonnull, warn_unused_result))
841
static int init_gnutls_session(gnutls_session_t *session,
538
844
/* GnuTLS session creation */
592
897
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
593
898
__attribute__((unused)) const char *txt){}
900
/* Set effective uid to 0, return errno */
901
__attribute__((warn_unused_result))
902
int raise_privileges(void){
903
int old_errno = errno;
905
if(seteuid(0) == -1){
912
/* Set effective and real user ID to 0. Return errno. */
913
__attribute__((warn_unused_result))
914
int raise_privileges_permanently(void){
915
int old_errno = errno;
916
int ret = raise_privileges();
928
/* Set effective user ID to unprivileged saved user ID */
929
__attribute__((warn_unused_result))
930
int lower_privileges(void){
931
int old_errno = errno;
933
if(seteuid(uid) == -1){
940
/* Lower privileges permanently */
941
__attribute__((warn_unused_result))
942
int lower_privileges_permanently(void){
943
int old_errno = errno;
945
if(setuid(uid) == -1){
952
/* Helper function to add_local_route() and delete_local_route() */
953
__attribute__((nonnull, warn_unused_result))
954
static bool add_delete_local_route(const bool add,
956
AvahiIfIndex if_index){
958
char helper[] = "mandos-client-iprouteadddel";
959
char add_arg[] = "add";
960
char delete_arg[] = "delete";
961
char debug_flag[] = "--debug";
962
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
963
if(pluginhelperdir == NULL){
965
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
966
" variable not set; cannot run helper\n");
971
char interface[IF_NAMESIZE];
972
if(if_indextoname((unsigned int)if_index, interface) == NULL){
973
perror_plus("if_indextoname");
977
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
979
perror_plus("open(\"/dev/null\", O_RDONLY)");
985
/* Raise privileges */
986
errno = raise_privileges_permanently();
988
perror_plus("Failed to raise privileges");
989
/* _exit(EX_NOPERM); */
995
perror_plus("setgid");
998
/* Reset supplementary groups */
1000
ret = setgroups(0, NULL);
1002
perror_plus("setgroups");
1006
ret = dup2(devnull, STDIN_FILENO);
1008
perror_plus("dup2(devnull, STDIN_FILENO)");
1011
ret = close(devnull);
1013
perror_plus("close");
1016
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1018
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1021
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1026
if(helperdir_fd == -1){
1027
perror_plus("open");
1028
_exit(EX_UNAVAILABLE);
1030
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1032
if(helper_fd == -1){
1033
perror_plus("openat");
1034
close(helperdir_fd);
1035
_exit(EX_UNAVAILABLE);
1037
close(helperdir_fd);
1039
#pragma GCC diagnostic push
1040
#pragma GCC diagnostic ignored "-Wcast-qual"
1042
if(fexecve(helper_fd, (char *const [])
1043
{ helper, add ? add_arg : delete_arg, (char *)address,
1044
interface, debug ? debug_flag : NULL, NULL },
1047
#pragma GCC diagnostic pop
1049
perror_plus("fexecve");
1050
_exit(EXIT_FAILURE);
1054
perror_plus("fork");
1061
pret = waitpid(pid, &status, 0);
1062
if(pret == -1 and errno == EINTR and quit_now){
1063
int errno_raising = 0;
1064
if((errno = raise_privileges()) != 0){
1065
errno_raising = errno;
1066
perror_plus("Failed to raise privileges in order to"
1067
" kill helper program");
1069
if(kill(pid, SIGTERM) == -1){
1070
perror_plus("kill");
1072
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1073
perror_plus("Failed to lower privileges after killing"
1078
} while(pret == -1 and errno == EINTR);
1080
perror_plus("waitpid");
1083
if(WIFEXITED(status)){
1084
if(WEXITSTATUS(status) != 0){
1085
fprintf_plus(stderr, "Error: iprouteadddel exited"
1086
" with status %d\n", WEXITSTATUS(status));
1091
if(WIFSIGNALED(status)){
1092
fprintf_plus(stderr, "Error: iprouteadddel died by"
1093
" signal %d\n", WTERMSIG(status));
1096
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1100
__attribute__((nonnull, warn_unused_result))
1101
static bool add_local_route(const char *address,
1102
AvahiIfIndex if_index){
1104
fprintf_plus(stderr, "Adding route to %s\n", address);
1106
return add_delete_local_route(true, address, if_index);
1109
__attribute__((nonnull, warn_unused_result))
1110
static bool delete_local_route(const char *address,
1111
AvahiIfIndex if_index){
1113
fprintf_plus(stderr, "Removing route to %s\n", address);
1115
return add_delete_local_route(false, address, if_index);
595
1118
/* Called when a Mandos server is found */
596
static int start_mandos_communication(const char *ip, uint16_t port,
1119
__attribute__((nonnull, warn_unused_result))
1120
static int start_mandos_communication(const char *ip, in_port_t port,
597
1121
AvahiIfIndex if_index,
1122
int af, mandos_context *mc){
599
1123
int ret, tcp_sd = -1;
602
struct sockaddr_in in;
603
struct sockaddr_in6 in6;
1125
struct sockaddr_storage to;
605
1126
char *buffer = NULL;
606
1127
char *decrypted_buffer = NULL;
607
1128
size_t buffer_length = 0;
629
fprintf(stderr, "Bad address family: %d\n", af);
1151
fprintf_plus(stderr, "Bad address family: %d\n", af);
634
ret = init_gnutls_session(&session);
1156
/* If the interface is specified and we have a list of interfaces */
1157
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1158
/* Check if the interface is one of the interfaces we are using */
1161
char *interface = NULL;
1162
while((interface = argz_next(mc->interfaces,
1163
mc->interfaces_size,
1165
if(if_nametoindex(interface) == (unsigned int)if_index){
1172
/* This interface does not match any in the list, so we don't
1173
connect to the server */
1175
char interface[IF_NAMESIZE];
1176
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1177
perror_plus("if_indextoname");
1179
fprintf_plus(stderr, "Skipping server on non-used interface"
1181
if_indextoname((unsigned int)if_index,
1189
ret = init_gnutls_session(&session, mc);
640
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1195
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1196
PRIuMAX "\n", ip, (uintmax_t)port);
644
tcp_sd = socket(pf, SOCK_STREAM, 0);
1199
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
647
1202
perror_plus("socket");
708
1258
if(if_indextoname((unsigned int)if_index, interface) == NULL){
709
1259
perror_plus("if_indextoname");
711
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
712
ip, interface, port);
1261
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1262
"\n", ip, interface, (uintmax_t)port);
715
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1265
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1266
ip, (uintmax_t)port);
718
1268
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
719
1269
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
722
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
725
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
729
perror_plus("inet_ntop");
731
if(strcmp(addrstr, ip) != 0){
732
fprintf(stderr, "Canonical address form: %s\n", addrstr);
743
ret = connect(tcp_sd, &to.in6, sizeof(to));
745
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
748
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
750
perror_plus("connect");
1271
ret = getnameinfo((struct sockaddr *)&to,
1272
sizeof(struct sockaddr_in6),
1273
addrstr, sizeof(addrstr), NULL, 0,
1276
ret = getnameinfo((struct sockaddr *)&to,
1277
sizeof(struct sockaddr_in),
1278
addrstr, sizeof(addrstr), NULL, 0,
1281
if(ret == EAI_SYSTEM){
1282
perror_plus("getnameinfo");
1283
} else if(ret != 0) {
1284
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1285
} else if(strcmp(addrstr, ip) != 0){
1286
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1297
ret = connect(tcp_sd, (struct sockaddr *)&to,
1298
sizeof(struct sockaddr_in6));
1300
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1301
sizeof(struct sockaddr_in));
1304
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1305
and if_index != AVAHI_IF_UNSPEC
1306
and connect_to == NULL
1307
and not route_added and
1308
((af == AF_INET6 and not
1309
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1311
or (af == AF_INET and
1312
/* Not a a IPv4LL address */
1313
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1314
& 0xFFFF0000L) != 0xA9FE0000L))){
1315
/* Work around Avahi bug - Avahi does not announce link-local
1316
addresses if it has a global address, so local hosts with
1317
*only* a link-local address (e.g. Mandos clients) cannot
1318
connect to a Mandos server announced by Avahi on a server
1319
host with a global address. Work around this by retrying
1320
with an explicit route added with the server's address.
1322
Avahi bug reference:
1323
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1324
https://bugs.debian.org/587961
1327
fprintf_plus(stderr, "Mandos server unreachable, trying"
1331
route_added = add_local_route(ip, if_index);
1337
if(errno != ECONNREFUSED or debug){
1339
perror_plus("connect");
761
1352
const char *out = mandos_protocol_version;
999
1615
char ip[AVAHI_ADDRESS_STR_MAX];
1000
1616
avahi_address_snprint(ip, sizeof(ip), address);
1002
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
1003
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
1004
ip, (intmax_t)interface, port);
1618
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1619
PRIdMAX ") on port %" PRIu16 "\n", name,
1620
host_name, ip, (intmax_t)interface, port);
1006
int ret = start_mandos_communication(ip, port, interface,
1007
avahi_proto_to_af(proto));
1622
int ret = start_mandos_communication(ip, (in_port_t)port,
1624
avahi_proto_to_af(proto),
1009
avahi_simple_poll_quit(mc.simple_poll);
1627
avahi_simple_poll_quit(simple_poll);
1011
ret = add_server(ip, port, interface,
1012
avahi_proto_to_af(proto));
1629
if(not add_server(ip, (in_port_t)port, interface,
1630
avahi_proto_to_af(proto),
1631
&((mandos_context*)mc)->current_server)){
1632
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1078
1707
signal_received = sig;
1079
1708
int old_errno = errno;
1080
1709
/* set main loop to exit */
1081
if(mc.simple_poll != NULL){
1082
avahi_simple_poll_quit(mc.simple_poll);
1710
if(simple_poll != NULL){
1711
avahi_simple_poll_quit(simple_poll);
1084
1713
errno = old_errno;
1716
__attribute__((nonnull, warn_unused_result))
1717
bool get_flags(const char *ifname, struct ifreq *ifr){
1721
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1724
perror_plus("socket");
1728
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1729
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1730
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1734
perror_plus("ioctl SIOCGIFFLAGS");
1737
if((close(s) == -1) and debug){
1739
perror_plus("close");
1744
if((close(s) == -1) and debug){
1746
perror_plus("close");
1752
__attribute__((nonnull, warn_unused_result))
1753
bool good_flags(const char *ifname, const struct ifreq *ifr){
1755
/* Reject the loopback device */
1756
if(ifr->ifr_flags & IFF_LOOPBACK){
1758
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1763
/* Accept point-to-point devices only if connect_to is specified */
1764
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1766
fprintf_plus(stderr, "Accepting point-to-point interface"
1767
" \"%s\"\n", ifname);
1771
/* Otherwise, reject non-broadcast-capable devices */
1772
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1774
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1775
" \"%s\"\n", ifname);
1779
/* Reject non-ARP interfaces (including dummy interfaces) */
1780
if(ifr->ifr_flags & IFF_NOARP){
1782
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1788
/* Accept this device */
1790
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1088
1796
* This function determines if a directory entry in /sys/class/net
1089
1797
* corresponds to an acceptable network device.
1090
1798
* (This function is passed to scandir(3) as a filter function.)
1800
__attribute__((nonnull, warn_unused_result))
1092
1801
int good_interface(const struct dirent *if_entry){
1094
char *flagname = NULL;
1095
1802
if(if_entry->d_name[0] == '.'){
1098
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1101
perror_plus("asprintf");
1104
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1106
perror_plus("open");
1111
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1112
/* read line from flags_fd */
1113
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1114
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1115
flagstring[(size_t)to_read] = '\0';
1116
if(flagstring == NULL){
1117
perror_plus("malloc");
1122
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1125
perror_plus("read");
1139
tmpmax = strtoimax(flagstring, &tmp, 0);
1140
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1141
and not (isspace(*tmp)))
1142
or tmpmax != (ifreq_flags)tmpmax){
1144
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1145
flagstring, if_entry->d_name);
1151
ifreq_flags flags = (ifreq_flags)tmpmax;
1152
/* Reject the loopback device */
1153
if(flags & IFF_LOOPBACK){
1155
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1163
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (flags & IFF_BROADCAST)){
1171
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(flags & IFF_NOARP){
1179
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1184
/* Accept this device */
1186
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1807
if(not get_flags(if_entry->d_name, &ifr)){
1809
fprintf_plus(stderr, "Failed to get flags for interface "
1810
"\"%s\"\n", if_entry->d_name);
1815
if(not good_flags(if_entry->d_name, &ifr)){
1822
* This function determines if a network interface is up.
1824
__attribute__((nonnull, warn_unused_result))
1825
bool interface_is_up(const char *interface){
1827
if(not get_flags(interface, &ifr)){
1829
fprintf_plus(stderr, "Failed to get flags for interface "
1830
"\"%s\"\n", interface);
1835
return (bool)(ifr.ifr_flags & IFF_UP);
1839
* This function determines if a network interface is running
1841
__attribute__((nonnull, warn_unused_result))
1842
bool interface_is_running(const char *interface){
1844
if(not get_flags(interface, &ifr)){
1846
fprintf_plus(stderr, "Failed to get flags for interface "
1847
"\"%s\"\n", interface);
1852
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1855
__attribute__((nonnull, pure, warn_unused_result))
1192
1856
int notdotentries(const struct dirent *direntry){
1193
1857
/* Skip "." and ".." */
1194
1858
if(direntry->d_name[0] == '.'
1203
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1867
/* Is this directory entry a runnable program? */
1868
__attribute__((nonnull, warn_unused_result))
1869
int runnable_hook(const struct dirent *direntry){
1874
if((direntry->d_name)[0] == '\0'){
1879
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1880
"abcdefghijklmnopqrstuvwxyz"
1883
if((direntry->d_name)[sret] != '\0'){
1884
/* Contains non-allowed characters */
1886
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1892
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1895
perror_plus("Could not stat hook");
1899
if(not (S_ISREG(st.st_mode))){
1900
/* Not a regular file */
1902
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1907
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1908
/* Not executable */
1910
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1916
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1922
__attribute__((nonnull, warn_unused_result))
1923
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1924
mandos_context *mc){
1205
1926
struct timespec now;
1206
1927
struct timespec waited_time;
1207
1928
intmax_t block_time;
1210
if(mc.current_server == NULL){
1213
"Wait until first server is found. No timeout!\n");
1931
if(mc->current_server == NULL){
1933
fprintf_plus(stderr, "Wait until first server is found."
1215
1936
ret = avahi_simple_poll_iterate(s, -1);
1218
fprintf(stderr, "Check current_server if we should run it,"
1939
fprintf_plus(stderr, "Check current_server if we should run"
1221
1942
/* the current time */
1222
1943
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1227
1948
/* Calculating in ms how long time between now and server
1228
1949
who we visted longest time ago. Now - last seen. */
1229
1950
waited_time.tv_sec = (now.tv_sec
1230
- mc.current_server->last_seen.tv_sec);
1951
- mc->current_server->last_seen.tv_sec);
1231
1952
waited_time.tv_nsec = (now.tv_nsec
1232
- mc.current_server->last_seen.tv_nsec);
1953
- mc->current_server->last_seen.tv_nsec);
1233
1954
/* total time is 10s/10,000ms.
1234
1955
Converting to s from ms by dividing by 1,000,
1235
1956
and ns to ms by dividing by 1,000,000. */
1236
1957
block_time = ((retry_interval
1237
1958
- ((intmax_t)waited_time.tv_sec * 1000))
1238
1959
- ((intmax_t)waited_time.tv_nsec / 1000000));
1241
fprintf(stderr, "Blocking for %ld ms\n", block_time);
1962
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1244
1966
if(block_time <= 0){
1245
ret = start_mandos_communication(mc.current_server->ip,
1246
mc.current_server->port,
1247
mc.current_server->if_index,
1248
mc.current_server->af);
1967
ret = start_mandos_communication(mc->current_server->ip,
1968
mc->current_server->port,
1969
mc->current_server->if_index,
1970
mc->current_server->af, mc);
1250
avahi_simple_poll_quit(mc.simple_poll);
1972
avahi_simple_poll_quit(s);
1253
1975
ret = clock_gettime(CLOCK_MONOTONIC,
1254
&mc.current_server->last_seen);
1976
&mc->current_server->last_seen);
1256
1978
perror_plus("clock_gettime");
1259
mc.current_server = mc.current_server->next;
1981
mc->current_server = mc->current_server->next;
1260
1982
block_time = 0; /* Call avahi to find new Mandos
1261
1983
servers, but don't block */
1264
1986
ret = avahi_simple_poll_iterate(s, (int)block_time);
1267
if (ret > 0 or errno != EINTR) {
1989
if(ret > 0 or errno != EINTR){
1268
1990
return (ret != 1) ? ret : 0;
1996
__attribute__((nonnull))
1997
void run_network_hooks(const char *mode, const char *interface,
1999
struct dirent **direntries = NULL;
2000
if(hookdir_fd == -1){
2001
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2003
if(hookdir_fd == -1){
2004
if(errno == ENOENT){
2006
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2007
" found\n", hookdir);
2010
perror_plus("open");
2015
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2017
perror_plus("open(\"/dev/null\", O_RDONLY)");
2020
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2021
runnable_hook, alphasort);
2023
perror_plus("scandir");
2027
struct dirent *direntry;
2029
for(int i = 0; i < numhooks; i++){
2030
direntry = direntries[i];
2032
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2035
pid_t hook_pid = fork();
2038
/* Raise privileges */
2039
errno = raise_privileges_permanently();
2041
perror_plus("Failed to raise privileges");
2048
perror_plus("setgid");
2051
/* Reset supplementary groups */
2053
ret = setgroups(0, NULL);
2055
perror_plus("setgroups");
2058
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2060
perror_plus("setenv");
2063
ret = setenv("DEVICE", interface, 1);
2065
perror_plus("setenv");
2068
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2070
perror_plus("setenv");
2073
ret = setenv("MODE", mode, 1);
2075
perror_plus("setenv");
2079
ret = asprintf(&delaystring, "%f", (double)delay);
2081
perror_plus("asprintf");
2084
ret = setenv("DELAY", delaystring, 1);
2087
perror_plus("setenv");
2091
if(connect_to != NULL){
2092
ret = setenv("CONNECT", connect_to, 1);
2094
perror_plus("setenv");
2098
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2102
perror_plus("openat");
2103
_exit(EXIT_FAILURE);
2105
if(close(hookdir_fd) == -1){
2106
perror_plus("close");
2107
_exit(EXIT_FAILURE);
2109
ret = dup2(devnull, STDIN_FILENO);
2111
perror_plus("dup2(devnull, STDIN_FILENO)");
2114
ret = close(devnull);
2116
perror_plus("close");
2119
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2121
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2124
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2126
perror_plus("fexecve");
2127
_exit(EXIT_FAILURE);
2131
perror_plus("fork");
2136
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2137
perror_plus("waitpid");
2141
if(WIFEXITED(status)){
2142
if(WEXITSTATUS(status) != 0){
2143
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2144
" with status %d\n", direntry->d_name,
2145
WEXITSTATUS(status));
2149
} else if(WIFSIGNALED(status)){
2150
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2151
" signal %d\n", direntry->d_name,
2156
fprintf_plus(stderr, "Warning: network hook \"%s\""
2157
" crashed\n", direntry->d_name);
2163
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2169
if(close(hookdir_fd) == -1){
2170
perror_plus("close");
2177
__attribute__((nonnull, warn_unused_result))
2178
int bring_up_interface(const char *const interface,
2180
int old_errno = errno;
2182
struct ifreq network;
2183
unsigned int if_index = if_nametoindex(interface);
2185
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2195
if(not interface_is_up(interface)){
2197
int ioctl_errno = 0;
2198
if(not get_flags(interface, &network)){
2200
fprintf_plus(stderr, "Failed to get flags for interface "
2201
"\"%s\"\n", interface);
2205
network.ifr_flags |= IFF_UP; /* set flag */
2207
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2210
perror_plus("socket");
2218
perror_plus("close");
2225
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2229
/* Raise privileges */
2230
ret_errno = raise_privileges();
2233
perror_plus("Failed to raise privileges");
2238
bool restore_loglevel = false;
2240
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2241
messages about the network interface to mess up the prompt */
2242
ret_linux = klogctl(8, NULL, 5);
2243
if(ret_linux == -1){
2244
perror_plus("klogctl");
2246
restore_loglevel = true;
2249
#endif /* __linux__ */
2250
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2251
ioctl_errno = errno;
2253
if(restore_loglevel){
2254
ret_linux = klogctl(7, NULL, 0);
2255
if(ret_linux == -1){
2256
perror_plus("klogctl");
2259
#endif /* __linux__ */
2261
/* If raise_privileges() succeeded above */
2263
/* Lower privileges */
2264
ret_errno = lower_privileges();
2267
perror_plus("Failed to lower privileges");
2271
/* Close the socket */
2274
perror_plus("close");
2277
if(ret_setflags == -1){
2278
errno = ioctl_errno;
2279
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2284
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2288
/* Sleep checking until interface is running.
2289
Check every 0.25s, up to total time of delay */
2290
for(int i = 0; i < delay * 4; i++){
2291
if(interface_is_running(interface)){
2294
struct timespec sleeptime = { .tv_nsec = 250000000 };
2295
ret = nanosleep(&sleeptime, NULL);
2296
if(ret == -1 and errno != EINTR){
2297
perror_plus("nanosleep");
2305
__attribute__((nonnull, warn_unused_result))
2306
int take_down_interface(const char *const interface){
2307
int old_errno = errno;
2308
struct ifreq network;
2309
unsigned int if_index = if_nametoindex(interface);
2311
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2315
if(interface_is_up(interface)){
2317
int ioctl_errno = 0;
2318
if(not get_flags(interface, &network) and debug){
2320
fprintf_plus(stderr, "Failed to get flags for interface "
2321
"\"%s\"\n", interface);
2325
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2327
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2330
perror_plus("socket");
2336
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2340
/* Raise privileges */
2341
ret_errno = raise_privileges();
2344
perror_plus("Failed to raise privileges");
2347
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2348
ioctl_errno = errno;
2350
/* If raise_privileges() succeeded above */
2352
/* Lower privileges */
2353
ret_errno = lower_privileges();
2356
perror_plus("Failed to lower privileges");
2360
/* Close the socket */
2361
int ret = close(sd);
2363
perror_plus("close");
2366
if(ret_setflags == -1){
2367
errno = ioctl_errno;
2368
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2373
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1274
2381
int main(int argc, char *argv[]){
2382
mandos_context mc = { .server = NULL, .dh_bits = 0,
2383
.priority = "SECURE256:!CTYPE-X.509"
2384
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2385
.current_server = NULL, .interfaces = NULL,
2386
.interfaces_size = 0 };
1275
2387
AvahiSServiceBrowser *sb = NULL;
1278
2390
intmax_t tmpmax;
1280
2392
int exitcode = EXIT_SUCCESS;
1281
const char *interface = "";
1282
struct ifreq network;
1284
bool take_down_interface = false;
1287
char tempdir[] = "/tmp/mandosXXXXXX";
1288
bool tempdir_created = false;
2393
char *interfaces_to_take_down = NULL;
2394
size_t interfaces_to_take_down_size = 0;
2395
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2396
char old_tempdir[] = "/tmp/mandosXXXXXX";
2397
char *tempdir = NULL;
1289
2398
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1290
2399
const char *seckey = PATHDIR "/" SECKEY;
1291
2400
const char *pubkey = PATHDIR "/" PUBKEY;
2401
const char *dh_params_file = NULL;
2402
char *interfaces_hooks = NULL;
1293
2404
bool gnutls_initialized = false;
1294
2405
bool gpgme_initialized = false;
1460
2591
/* Work around Debian bug #633582:
1461
<http://bugs.debian.org/633582> */
1464
/* Re-raise priviliges */
1468
perror_plus("seteuid");
1471
int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);
1472
if(seckey_fd == -1){
1473
perror_plus("open");
1475
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1477
perror_plus("fstat");
1479
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1480
ret = fchown(seckey_fd, uid, gid);
1482
perror_plus("fchown");
1486
TEMP_FAILURE_RETRY(close(seckey_fd));
1489
int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);
1490
if(pubkey_fd == -1){
1491
perror_plus("open");
1493
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1495
perror_plus("fstat");
1497
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1498
ret = fchown(pubkey_fd, uid, gid);
1500
perror_plus("fchown");
1504
TEMP_FAILURE_RETRY(close(pubkey_fd));
1507
/* Lower privileges */
1511
perror_plus("seteuid");
2592
<https://bugs.debian.org/633582> */
2594
/* Re-raise privileges */
2595
ret = raise_privileges();
2598
perror_plus("Failed to raise privileges");
2602
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2603
int seckey_fd = open(seckey, O_RDONLY);
2604
if(seckey_fd == -1){
2605
perror_plus("open");
2607
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2609
perror_plus("fstat");
2611
if(S_ISREG(st.st_mode)
2612
and st.st_uid == 0 and st.st_gid == 0){
2613
ret = fchown(seckey_fd, uid, gid);
2615
perror_plus("fchown");
2623
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2624
int pubkey_fd = open(pubkey, O_RDONLY);
2625
if(pubkey_fd == -1){
2626
perror_plus("open");
2628
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2630
perror_plus("fstat");
2632
if(S_ISREG(st.st_mode)
2633
and st.st_uid == 0 and st.st_gid == 0){
2634
ret = fchown(pubkey_fd, uid, gid);
2636
perror_plus("fchown");
2644
if(dh_params_file != NULL
2645
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2646
int dhparams_fd = open(dh_params_file, O_RDONLY);
2647
if(dhparams_fd == -1){
2648
perror_plus("open");
2650
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2652
perror_plus("fstat");
2654
if(S_ISREG(st.st_mode)
2655
and st.st_uid == 0 and st.st_gid == 0){
2656
ret = fchown(dhparams_fd, uid, gid);
2658
perror_plus("fchown");
2666
/* Lower privileges */
2667
ret = lower_privileges();
2670
perror_plus("Failed to lower privileges");
2675
/* Remove invalid interface names (except "none") */
2677
char *interface = NULL;
2678
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2680
if(strcmp(interface, "none") != 0
2681
and if_nametoindex(interface) == 0){
2682
if(interface[0] != '\0'){
2683
fprintf_plus(stderr, "Not using nonexisting interface"
2684
" \"%s\"\n", interface);
2686
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2692
/* Run network hooks */
2694
if(mc.interfaces != NULL){
2695
interfaces_hooks = malloc(mc.interfaces_size);
2696
if(interfaces_hooks == NULL){
2697
perror_plus("malloc");
2700
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2701
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2703
run_network_hooks("start", interfaces_hooks != NULL ?
2704
interfaces_hooks : "", delay);
1516
2708
avahi_set_log_function(empty_log);
1519
if(interface[0] == '\0'){
1520
struct dirent **direntries;
1521
ret = scandir(sys_class_net, &direntries, good_interface,
1524
/* Pick the first good interface */
1525
interface = strdup(direntries[0]->d_name);
1527
fprintf(stderr, "Using interface \"%s\"\n", interface);
1529
if(interface == NULL){
1530
perror_plus("malloc");
1532
exitcode = EXIT_FAILURE;
1538
fprintf(stderr, "Could not find a network interface\n");
1539
exitcode = EXIT_FAILURE;
1544
2711
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1545
2712
from the signal handler */
1546
2713
/* Initialize the pseudo-RNG for Avahi */
1547
2714
srand((unsigned int) time(NULL));
1548
mc.simple_poll = avahi_simple_poll_new();
1549
if(mc.simple_poll == NULL){
1550
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2715
simple_poll = avahi_simple_poll_new();
2716
if(simple_poll == NULL){
2717
fprintf_plus(stderr,
2718
"Avahi: Failed to create simple poll object.\n");
1551
2719
exitcode = EX_UNAVAILABLE;
1618
/* If the interface is down, bring it up */
1619
if(strcmp(interface, "none") != 0){
1620
if_index = (AvahiIfIndex) if_nametoindex(interface);
1622
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1623
exitcode = EX_UNAVAILABLE;
1631
/* Re-raise priviliges */
1635
perror_plus("seteuid");
1639
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1640
messages about the network interface to mess up the prompt */
1641
ret = klogctl(8, NULL, 5);
1642
bool restore_loglevel = true;
1644
restore_loglevel = false;
1645
perror_plus("klogctl");
1647
#endif /* __linux__ */
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1651
perror_plus("socket");
1652
exitcode = EX_OSERR;
1654
if(restore_loglevel){
1655
ret = klogctl(7, NULL, 0);
1657
perror_plus("klogctl");
1660
#endif /* __linux__ */
1661
/* Lower privileges */
1665
perror_plus("seteuid");
1669
strcpy(network.ifr_name, interface);
1670
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1672
perror_plus("ioctl SIOCGIFFLAGS");
1674
if(restore_loglevel){
1675
ret = klogctl(7, NULL, 0);
1677
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
exitcode = EX_OSERR;
1682
/* Lower privileges */
1686
perror_plus("seteuid");
1690
if((network.ifr_flags & IFF_UP) == 0){
1691
network.ifr_flags |= IFF_UP;
1692
take_down_interface = true;
1693
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1695
take_down_interface = false;
1696
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1697
exitcode = EX_OSERR;
1699
if(restore_loglevel){
1700
ret = klogctl(7, NULL, 0);
1702
perror_plus("klogctl");
2786
/* If no interfaces were specified, make a list */
2787
if(mc.interfaces == NULL){
2788
struct dirent **direntries = NULL;
2789
/* Look for any good interfaces */
2790
ret = scandir(sys_class_net, &direntries, good_interface,
2793
/* Add all found interfaces to interfaces list */
2794
for(int i = 0; i < ret; ++i){
2795
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2796
direntries[i]->d_name);
2799
perror_plus("argz_add");
2800
free(direntries[i]);
2804
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2805
direntries[i]->d_name);
2807
free(direntries[i]);
2814
fprintf_plus(stderr, "Could not find a network interface\n");
2815
exitcode = EXIT_FAILURE;
2820
/* Bring up interfaces which are down, and remove any "none"s */
2822
char *interface = NULL;
2823
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2825
/* If interface name is "none", stop bringing up interfaces.
2826
Also remove all instances of "none" from the list */
2827
if(strcmp(interface, "none") == 0){
2828
argz_delete(&mc.interfaces, &mc.interfaces_size,
2831
while((interface = argz_next(mc.interfaces,
2832
mc.interfaces_size, interface))){
2833
if(strcmp(interface, "none") == 0){
2834
argz_delete(&mc.interfaces, &mc.interfaces_size,
1705
#endif /* __linux__ */
1706
/* Lower privileges */
1710
perror_plus("seteuid");
1715
/* Sleep checking until interface is running.
1716
Check every 0.25s, up to total time of delay */
1717
for(int i=0; i < delay * 4; i++){
1718
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1720
perror_plus("ioctl SIOCGIFFLAGS");
1721
} else if(network.ifr_flags & IFF_RUNNING){
1724
struct timespec sleeptime = { .tv_nsec = 250000000 };
1725
ret = nanosleep(&sleeptime, NULL);
1726
if(ret == -1 and errno != EINTR){
1727
perror_plus("nanosleep");
1730
if(not take_down_interface){
1731
/* We won't need the socket anymore */
1732
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1734
perror_plus("close");
1738
if(restore_loglevel){
1739
/* Restores kernel loglevel to default */
1740
ret = klogctl(7, NULL, 0);
1742
perror_plus("klogctl");
1745
#endif /* __linux__ */
1746
/* Lower privileges */
1748
if(take_down_interface){
1749
/* Lower privileges */
1752
perror_plus("seteuid");
1755
/* Lower privileges permanently */
1758
perror_plus("setuid");
2841
bool interface_was_up = interface_is_up(interface);
2842
errno = bring_up_interface(interface, delay);
2843
if(not interface_was_up){
2845
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2846
" %s\n", interface, strerror(errno));
2848
errno = argz_add(&interfaces_to_take_down,
2849
&interfaces_to_take_down_size,
2852
perror_plus("argz_add");
2857
if(debug and (interfaces_to_take_down == NULL)){
2858
fprintf_plus(stderr, "No interfaces were brought up\n");
2862
/* If we only got one interface, explicitly use only that one */
2863
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2865
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2868
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1767
ret = init_gnutls_global(pubkey, seckey);
2875
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1769
fprintf(stderr, "init_gnutls_global failed\n");
2877
fprintf_plus(stderr, "init_gnutls_global failed\n");
1770
2878
exitcode = EX_UNAVAILABLE;
1909
3037
/* Run the main loop */
1912
fprintf(stderr, "Starting Avahi loop search\n");
3040
fprintf_plus(stderr, "Starting Avahi loop search\n");
1915
ret = avahi_loop_with_timeout(mc.simple_poll,
1916
(int)(retry_interval * 1000));
3043
ret = avahi_loop_with_timeout(simple_poll,
3044
(int)(retry_interval * 1000), &mc);
1918
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
1919
(ret == 0) ? "successfully" : "with error");
3046
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
3047
(ret == 0) ? "successfully" : "with error");
1925
fprintf(stderr, "%s exiting\n", argv[0]);
3053
if(signal_received){
3054
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
3055
argv[0], signal_received,
3056
strsignal(signal_received));
3058
fprintf_plus(stderr, "%s exiting\n", argv[0]);
1928
3062
/* Cleanup things */
3063
free(mc.interfaces);
1930
3066
avahi_s_service_browser_free(sb);
1932
3068
if(mc.server != NULL)
1933
3069
avahi_server_free(mc.server);
1935
if(mc.simple_poll != NULL)
1936
avahi_simple_poll_free(mc.simple_poll);
3071
if(simple_poll != NULL)
3072
avahi_simple_poll_free(simple_poll);
1938
3074
if(gnutls_initialized){
1939
3075
gnutls_certificate_free_credentials(mc.cred);
1940
gnutls_global_deinit();
1941
3076
gnutls_dh_params_deinit(mc.dh_params);
1944
3079
if(gpgme_initialized){
1945
3080
gpgme_release(mc.ctx);
1948
3083
/* Cleans up the circular linked list of Mandos servers the client
1950
3085
if(mc.current_server != NULL){
1951
3086
mc.current_server->prev->next = NULL;
1952
3087
while(mc.current_server != NULL){
1953
3088
server *next = mc.current_server->next;
3090
#pragma GCC diagnostic push
3091
#pragma GCC diagnostic ignored "-Wcast-qual"
3093
free((char *)(mc.current_server->ip));
3095
#pragma GCC diagnostic pop
1954
3097
free(mc.current_server);
1955
3098
mc.current_server = next;
1959
/* Take down the network interface */
1960
if(take_down_interface){
1961
/* Re-raise priviliges */
1965
perror_plus("seteuid");
1968
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1970
perror_plus("ioctl SIOCGIFFLAGS");
1971
} else if(network.ifr_flags & IFF_UP) {
1972
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1975
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1978
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1980
perror_plus("close");
1982
/* Lower privileges permanently */
1986
perror_plus("setuid");
3102
/* Re-raise privileges */
3104
ret = raise_privileges();
3107
perror_plus("Failed to raise privileges");
3110
/* Run network hooks */
3111
run_network_hooks("stop", interfaces_hooks != NULL ?
3112
interfaces_hooks : "", delay);
3114
/* Take down the network interfaces which were brought up */
3116
char *interface = NULL;
3117
while((interface = argz_next(interfaces_to_take_down,
3118
interfaces_to_take_down_size,
3120
ret = take_down_interface(interface);
3123
perror_plus("Failed to take down interface");
3126
if(debug and (interfaces_to_take_down == NULL)){
3127
fprintf_plus(stderr, "No interfaces needed to be taken"
3133
ret = lower_privileges_permanently();
3136
perror_plus("Failed to lower privileges permanently");
3140
free(interfaces_to_take_down);
3141
free(interfaces_hooks);
3143
void clean_dir_at(int base, const char * const dirname,
3145
struct dirent **direntries = NULL;
3147
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3153
perror_plus("open");
3156
int numentries = scandirat(dir_fd, ".", &direntries,
3157
notdotentries, alphasort);
3158
if(numentries >= 0){
3159
for(int i = 0; i < numentries; i++){
3161
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3162
dirname, direntries[i]->d_name);
3164
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3166
if(errno == EISDIR){
3167
dret = unlinkat(dir_fd, direntries[i]->d_name,
3170
if((dret == -1) and (errno == ENOTEMPTY)
3171
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3172
== 0) and (level == 0)){
3173
/* Recurse only in this special case */
3174
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3177
if((dret == -1) and (errno != ENOENT)){
3178
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3179
direntries[i]->d_name, strerror(errno));
3182
free(direntries[i]);
3185
/* need to clean even if 0 because man page doesn't specify */
3187
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3188
if(dret == -1 and errno != ENOENT){
3189
perror_plus("rmdir");
3192
perror_plus("scandirat");
1991
3197
/* Removes the GPGME temp directory and all files inside */
1992
if(tempdir_created){
1993
struct dirent **direntries = NULL;
1994
struct dirent *direntry = NULL;
1995
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
1997
for(int i = 0; i < ret; i++){
1998
direntry = direntries[i];
1999
char *fullname = NULL;
2000
ret = asprintf(&fullname, "%s/%s", tempdir,
2003
perror_plus("asprintf");
2006
ret = remove(fullname);
2008
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2015
/* need to be cleaned even if ret == 0 because man page doesn't
2019
perror_plus("scandir");
2021
ret = rmdir(tempdir);
2022
if(ret == -1 and errno != ENOENT){
2023
perror_plus("rmdir");
3198
if(tempdir != NULL){
3199
clean_dir_at(-1, tempdir, 0);