9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
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
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
23
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
24
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25
23
* General Public License for more details.
27
25
* You should have received a copy of the GNU General Public License
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
30
* Contact the authors at <mandos@recompile.se>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
33
32
/* Needed by GPGME, specifically gpgme_data_seek() */
34
33
#ifndef _LARGEFILE_SOURCE
35
34
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
37
36
#ifndef _FILE_OFFSET_BITS
38
37
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
41
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
43
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
46
45
#include <stddef.h> /* NULL, size_t, ssize_t */
47
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
47
strtof(), abort() */
49
48
#include <stdbool.h> /* bool, false, true */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
53
51
#include <sys/ioctl.h> /* ioctl */
54
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
55
53
sockaddr_in6, PF_INET6,
56
54
SOCK_STREAM, uid_t, gid_t, open(),
58
#include <sys/stat.h> /* open(), S_ISREG */
56
#include <sys/stat.h> /* open() */
59
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
60
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
63
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
65
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
68
EAI_SYSTEM, ENETUNREACH,
69
EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
72
program_invocation_short_name */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
73
66
#include <time.h> /* nanosleep(), time(), sleep() */
74
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
75
68
SIOCSIFFLAGS, if_indextoname(),
145
122
#define PATHDIR "/conf/conf.d/mandos"
146
123
#define SECKEY "seckey.txt"
147
124
#define PUBKEY "pubkey.txt"
148
#define TLS_PRIVKEY "tls-privkey.pem"
149
#define TLS_PUBKEY "tls-pubkey.pem"
150
#define HOOKDIR "/lib/mandos/network-hooks.d"
152
126
bool debug = false;
153
127
static const char mandos_protocol_version[] = "1";
154
128
const char *argp_program_version = "mandos-client " VERSION;
155
const char *argp_program_bug_address = "<mandos@recompile.se>";
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
156
130
static const char sys_class_net[] = "/sys/class/net";
157
131
char *connect_to = NULL;
158
const char *hookdir = HOOKDIR;
163
/* Doubly linked list that need to be circularly linked when used */
164
typedef struct server{
167
AvahiIfIndex if_index;
169
struct timespec last_seen;
174
133
/* Used for passing in values through the Avahi callback functions */
135
AvahiSimplePoll *simple_poll;
176
136
AvahiServer *server;
177
137
gnutls_certificate_credentials_t cred;
178
138
unsigned int dh_bits;
179
139
gnutls_dh_params_t dh_params;
180
140
const char *priority;
182
server *current_server;
184
size_t interfaces_size;
185
142
} mandos_context;
187
/* global so signal handler can reach it*/
188
AvahiSimplePoll *simple_poll;
144
/* global context so signal handler can reach it*/
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
190
149
sig_atomic_t quit_now = 0;
191
150
int signal_received = 0;
193
/* Function to use when printing errors */
194
void perror_plus(const char *print_text){
196
fprintf(stderr, "Mandos plugin %s: ",
197
program_invocation_short_name);
202
__attribute__((format (gnu_printf, 2, 3), nonnull))
203
int fprintf_plus(FILE *stream, const char *format, ...){
205
va_start (ap, format);
207
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
208
program_invocation_short_name));
209
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
213
153
* Make additional room in "buffer" for at least BUFFER_SIZE more
214
154
* bytes. "buffer_capacity" is how much is currently allocated,
215
155
* "buffer_length" is how much is already used.
217
__attribute__((nonnull, warn_unused_result))
218
157
size_t incbuffer(char **buffer, size_t buffer_length,
219
size_t buffer_capacity){
158
size_t buffer_capacity){
220
159
if(buffer_length + BUFFER_SIZE > buffer_capacity){
221
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
223
int old_errno = errno;
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
230
164
buffer_capacity += BUFFER_SIZE;
232
166
return buffer_capacity;
235
/* Add server to set of servers to retry periodically */
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){
240
server *new_server = malloc(sizeof(server));
241
if(new_server == NULL){
242
perror_plus("malloc");
245
*new_server = (server){ .ip = strdup(ip),
247
.if_index = if_index,
249
if(new_server->ip == NULL){
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
268
/* Special case of first server */
269
if(*current_server == NULL){
270
new_server->next = new_server;
271
new_server->prev = new_server;
272
*current_server = new_server;
274
/* Place the new server last in the list */
275
new_server->next = *current_server;
276
new_server->prev = (*current_server)->prev;
277
new_server->prev->next = new_server;
278
(*current_server)->prev = new_server;
283
/* Set effective uid to 0, return errno */
284
__attribute__((warn_unused_result))
285
int raise_privileges(void){
286
int old_errno = errno;
288
if(seteuid(0) == -1){
295
/* Set effective and real user ID to 0. Return errno. */
296
__attribute__((warn_unused_result))
297
int raise_privileges_permanently(void){
298
int old_errno = errno;
299
int ret = raise_privileges();
311
/* Set effective user ID to unprivileged saved user ID */
312
__attribute__((warn_unused_result))
313
int lower_privileges(void){
314
int old_errno = errno;
316
if(seteuid(uid) == -1){
323
/* Lower privileges permanently */
324
__attribute__((warn_unused_result))
325
int lower_privileges_permanently(void){
326
int old_errno = errno;
328
if(setuid(uid) == -1){
336
170
* Initialize GPGME.
338
__attribute__((nonnull, warn_unused_result))
339
static bool init_gpgme(const char * const seckey,
340
const char * const pubkey,
341
const char * const tempdir,
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
343
174
gpgme_error_t rc;
344
175
gpgme_engine_info_t engine_info;
347
179
* Helper function to insert pub and seckey to the engine keyring.
349
bool import_key(const char * const filename){
181
bool import_key(const char *filename){
352
184
gpgme_data_t pgp_data;
354
186
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
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");
410
192
rc = gpgme_data_new_from_fd(&pgp_data, fd);
411
193
if(rc != GPG_ERR_NO_ERROR){
412
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
194
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
417
rc = gpgme_op_import(mc->ctx, pgp_data);
199
rc = gpgme_op_import(mc.ctx, pgp_data);
418
200
if(rc != GPG_ERR_NO_ERROR){
419
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
420
gpgme_strsource(rc), gpgme_strerror(rc));
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
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");
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
501
perror_plus("close");
503
210
gpgme_data_release(pgp_data);
508
fprintf_plus(stderr, "Initializing GPGME\n");
215
fprintf(stderr, "Initializing GPGME\n");
512
219
gpgme_check_version(NULL);
513
220
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
514
221
if(rc != GPG_ERR_NO_ERROR){
515
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
516
gpgme_strsource(rc), gpgme_strerror(rc));
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
520
/* Set GPGME home directory for the OpenPGP engine only */
227
/* Set GPGME home directory for the OpenPGP engine only */
521
228
rc = gpgme_get_engine_info(&engine_info);
522
229
if(rc != GPG_ERR_NO_ERROR){
523
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
524
gpgme_strsource(rc), gpgme_strerror(rc));
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
527
234
while(engine_info != NULL){
569
273
ssize_t plaintext_length = 0;
572
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
575
279
/* Create new GPGME data buffer from memory cryptotext */
576
280
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
578
282
if(rc != GPG_ERR_NO_ERROR){
579
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
580
gpgme_strsource(rc), gpgme_strerror(rc));
283
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
284
gpgme_strsource(rc), gpgme_strerror(rc));
584
288
/* Create new empty GPGME data buffer for the plaintext */
585
289
rc = gpgme_data_new(&dh_plain);
586
290
if(rc != GPG_ERR_NO_ERROR){
587
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
588
gpgme_strsource(rc), gpgme_strerror(rc));
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
589
293
gpgme_data_release(dh_crypto);
593
297
/* Decrypt data from the cryptotext data buffer to the plaintext
595
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
596
300
if(rc != GPG_ERR_NO_ERROR){
597
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
598
gpgme_strsource(rc), gpgme_strerror(rc));
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
599
303
plaintext_length = -1;
601
305
gpgme_decrypt_result_t result;
602
result = gpgme_op_decrypt_result(mc->ctx);
306
result = gpgme_op_decrypt_result(mc.ctx);
603
307
if(result == NULL){
604
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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");
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
612
314
if(result->file_name != NULL){
613
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
fprintf(stderr, "File name: %s\n", result->file_name);
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");
317
gpgme_recipient_t recipient;
318
recipient = result->recipients;
319
while(recipient != NULL){
320
fprintf(stderr, "Public key algorithm: %s\n",
321
gpgme_pubkey_algo_name(recipient->pubkey_algo));
322
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
323
fprintf(stderr, "Secret key available: %s\n",
324
recipient->status == GPG_ERR_NO_SECKEY
326
recipient = recipient->next;
723
425
/* OpenPGP credentials */
724
ret = gnutls_certificate_allocate_credentials(&mc->cred);
426
gnutls_certificate_allocate_credentials(&mc.cred);
725
427
if(ret != GNUTLS_E_SUCCESS){
726
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
727
safer_gnutls_strerror(ret));
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
432
safer_gnutls_strerror(ret));
433
gnutls_global_deinit();
732
fprintf_plus(stderr, "Attempting to use public key %s and"
733
" private key %s as GnuTLS credentials\n",
438
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
439
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
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
751
443
ret = gnutls_certificate_set_openpgp_key_file
752
(mc->cred, pubkeyfilename, seckeyfilename,
444
(mc.cred, pubkeyfilename, seckeyfilename,
753
445
GNUTLS_OPENPGP_FMT_BASE64);
755
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
757
446
if(ret != GNUTLS_E_SUCCESS){
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));
448
"Error[%d] while reading the OpenPGP key pair ('%s',"
449
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
450
fprintf(stderr, "The GnuTLS error is: %s\n",
451
safer_gnutls_strerror(ret));
766
455
/* GnuTLS server initialization */
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);
456
ret = gnutls_dh_params_init(&mc.dh_params);
457
if(ret != GNUTLS_E_SUCCESS){
458
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
459
" %s\n", safer_gnutls_strerror(ret));
462
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
463
if(ret != GNUTLS_E_SUCCESS){
464
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
465
safer_gnutls_strerror(ret));
469
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
961
gnutls_certificate_free_credentials(mc->cred);
962
gnutls_dh_params_deinit(mc->dh_params);
475
gnutls_certificate_free_credentials(mc.cred);
476
gnutls_global_deinit();
477
gnutls_dh_params_deinit(mc.dh_params);
966
__attribute__((nonnull, warn_unused_result))
967
static int init_gnutls_session(gnutls_session_t *session,
481
static int init_gnutls_session(gnutls_session_t *session){
970
483
/* GnuTLS session creation */
972
ret = gnutls_init(session, (GNUTLS_SERVER
973
#if GNUTLS_VERSION_NUMBER >= 0x030506
976
#if GNUTLS_VERSION_NUMBER >= 0x030606
977
| GNUTLS_ENABLE_RAWPK
485
ret = gnutls_init(session, GNUTLS_SERVER);
983
489
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
984
490
if(ret != GNUTLS_E_SUCCESS){
986
"Error in GnuTLS session initialization: %s\n",
987
safer_gnutls_strerror(ret));
491
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
492
safer_gnutls_strerror(ret));
993
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
498
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
995
500
gnutls_deinit(*session);
998
503
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
999
504
if(ret != GNUTLS_E_SUCCESS){
1000
fprintf_plus(stderr, "Syntax error at: %s\n", err);
1001
fprintf_plus(stderr, "GnuTLS error: %s\n",
1002
safer_gnutls_strerror(ret));
505
fprintf(stderr, "Syntax error at: %s\n", err);
506
fprintf(stderr, "GnuTLS error: %s\n",
507
safer_gnutls_strerror(ret));
1003
508
gnutls_deinit(*session);
1030
537
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
1031
538
__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);
1199
540
/* Called when a Mandos server is found */
1200
__attribute__((nonnull, warn_unused_result))
1201
static int start_mandos_communication(const char *ip, in_port_t port,
541
static int start_mandos_communication(const char *ip, uint16_t port,
1202
542
AvahiIfIndex if_index,
1203
int af, mandos_context *mc){
1204
544
int ret, tcp_sd = -1;
1206
struct sockaddr_storage to;
547
struct sockaddr_in in;
548
struct sockaddr_in6 in6;
1207
550
char *buffer = NULL;
1208
551
char *decrypted_buffer = NULL;
1209
552
size_t buffer_length = 0;
1337
651
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1338
652
char interface[IF_NAMESIZE];
1339
653
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1340
perror_plus("if_indextoname");
654
perror("if_indextoname");
1342
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1343
"\n", ip, interface, (uintmax_t)port);
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
1346
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1347
ip, (uintmax_t)port);
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1349
663
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1350
664
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
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");
667
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
670
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
676
if(strcmp(addrstr, ip) != 0){
677
fprintf(stderr, "Canonical address form: %s\n", addrstr);
688
ret = connect(tcp_sd, &to.in6, sizeof(to));
690
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
693
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
1433
706
const char *out = mandos_protocol_version;
1788
1019
signal_received = sig;
1789
1020
int old_errno = errno;
1790
/* set main loop to exit */
1791
if(simple_poll != NULL){
1792
avahi_simple_poll_quit(simple_poll);
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1794
1024
errno = old_errno;
1797
__attribute__((nonnull, warn_unused_result))
1798
bool get_flags(const char *ifname, struct ifreq *ifr){
1802
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1805
perror_plus("socket");
1809
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1810
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1811
ret = ioctl(s, SIOCGIFFLAGS, ifr);
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))
1834
bool good_flags(const char *ifname, const struct ifreq *ifr){
1836
/* Reject the loopback device */
1837
if(ifr->ifr_flags & IFF_LOOPBACK){
1839
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1844
/* Accept point-to-point devices only if connect_to is specified */
1845
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1847
fprintf_plus(stderr, "Accepting point-to-point interface"
1848
" \"%s\"\n", ifname);
1852
/* Otherwise, reject non-broadcast-capable devices */
1853
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1855
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1856
" \"%s\"\n", ifname);
1860
/* Reject non-ARP interfaces (including dummy interfaces) */
1861
if(ifr->ifr_flags & IFF_NOARP){
1863
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1869
/* Accept this device */
1871
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1877
1028
* This function determines if a directory entry in /sys/class/net
1878
1029
* corresponds to an acceptable network device.
1879
1030
* (This function is passed to scandir(3) as a filter function.)
1881
__attribute__((nonnull, warn_unused_result))
1882
1032
int good_interface(const struct dirent *if_entry){
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1883
1041
if(if_entry->d_name[0] == '.'){
1888
if(not get_flags(if_entry->d_name, &ifr)){
1890
fprintf_plus(stderr, "Failed to get flags for interface "
1891
"\"%s\"\n", if_entry->d_name);
1896
if(not good_flags(if_entry->d_name, &ifr)){
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))
1937
int notdotentries(const struct dirent *direntry){
1938
/* Skip "." and ".." */
1939
if(direntry->d_name[0] == '.'
1940
and (direntry->d_name[1] == '\0'
1941
or (direntry->d_name[1] == '.'
1942
and direntry->d_name[2] == '\0'))){
1948
/* Is this directory entry a runnable program? */
1949
__attribute__((nonnull, warn_unused_result))
1950
int runnable_hook(const struct dirent *direntry){
1955
if((direntry->d_name)[0] == '\0'){
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);
1976
perror_plus("Could not stat hook");
1980
if(not (S_ISREG(st.st_mode))){
1981
/* Not a regular file */
1983
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1988
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1989
/* Not executable */
1991
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1049
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1050
/* read line from flags_fd */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1052
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1053
flagstring[(size_t)to_read] = '\0';
1054
if(flagstring == NULL){
1060
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1077
tmpmax = strtoimax(flagstring, &tmp, 0);
1078
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1079
and not (isspace(*tmp)))
1080
or tmpmax != (ifreq_flags)tmpmax){
1082
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1083
flagstring, if_entry->d_name);
1089
ifreq_flags flags = (ifreq_flags)tmpmax;
1090
/* Reject the loopback device */
1091
if(flags & IFF_LOOPBACK){
1093
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1098
/* Accept point-to-point devices only if connect_to is specified */
1099
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1101
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1106
/* Otherwise, reject non-broadcast-capable devices */
1107
if(not (flags & IFF_BROADCAST)){
1109
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1114
/* Accept this device */
1997
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
2003
__attribute__((nonnull, warn_unused_result))
2004
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
2005
mandos_context *mc){
2007
struct timespec now;
2008
struct timespec waited_time;
2009
intmax_t block_time;
2012
if(mc->current_server == NULL){
2014
fprintf_plus(stderr, "Wait until first server is found."
2017
ret = avahi_simple_poll_iterate(s, -1);
2020
fprintf_plus(stderr, "Check current_server if we should run"
2023
/* the current time */
2024
ret = clock_gettime(CLOCK_MONOTONIC, &now);
2026
perror_plus("clock_gettime");
2029
/* Calculating in ms how long time between now and server
2030
who we visted longest time ago. Now - last seen. */
2031
waited_time.tv_sec = (now.tv_sec
2032
- mc->current_server->last_seen.tv_sec);
2033
waited_time.tv_nsec = (now.tv_nsec
2034
- mc->current_server->last_seen.tv_nsec);
2035
/* total time is 10s/10,000ms.
2036
Converting to s from ms by dividing by 1,000,
2037
and ns to ms by dividing by 1,000,000. */
2038
block_time = ((retry_interval
2039
- ((intmax_t)waited_time.tv_sec * 1000))
2040
- ((intmax_t)waited_time.tv_nsec / 1000000));
2043
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
2047
if(block_time <= 0){
2048
ret = start_mandos_communication(mc->current_server->ip,
2049
mc->current_server->port,
2050
mc->current_server->if_index,
2051
mc->current_server->af, mc);
2053
avahi_simple_poll_quit(s);
2056
ret = clock_gettime(CLOCK_MONOTONIC,
2057
&mc->current_server->last_seen);
2059
perror_plus("clock_gettime");
2062
mc->current_server = mc->current_server->next;
2063
block_time = 0; /* Call avahi to find new Mandos
2064
servers, but don't block */
2067
ret = avahi_simple_poll_iterate(s, (int)block_time);
2070
if(ret > 0 or errno != EINTR){
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",
2462
1122
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 };
2476
1123
AvahiSServiceBrowser *sb = NULL;
2479
1126
intmax_t tmpmax;
2481
1128
int exitcode = EXIT_SUCCESS;
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;
1129
const char *interface = "";
1130
struct ifreq network;
1132
bool take_down_interface = false;
1135
char tempdir[] = "/tmp/mandosXXXXXX";
1136
bool tempdir_created = false;
2487
1137
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2488
1138
const char *seckey = PATHDIR "/" SECKEY;
2489
1139
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;
2497
1141
bool gnutls_initialized = false;
2498
1142
bool gpgme_initialized = false;
2499
1143
float delay = 2.5f;
2500
double retry_interval = 10; /* 10s between trying a server and
2501
retrying the same server again */
2503
1145
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2504
1146
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2710
/* Work around Debian bug #633582:
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);
2827
1295
avahi_set_log_function(empty_log);
1298
if(interface[0] == '\0'){
1299
struct dirent **direntries;
1300
ret = scandir(sys_class_net, &direntries, good_interface,
1303
/* Pick the first good interface */
1304
interface = strdup(direntries[0]->d_name);
1306
fprintf(stderr, "Using interface \"%s\"\n", interface);
1308
if(interface == NULL){
1311
exitcode = EXIT_FAILURE;
1317
fprintf(stderr, "Could not find a network interface\n");
1318
exitcode = EXIT_FAILURE;
2830
1323
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2831
1324
from the signal handler */
2832
1325
/* Initialize the pseudo-RNG for Avahi */
2833
1326
srand((unsigned int) time(NULL));
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");
1327
mc.simple_poll = avahi_simple_poll_new();
1328
if(mc.simple_poll == NULL){
1329
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2838
1330
exitcode = EX_UNAVAILABLE;
2865
1357
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2867
perror_plus("sigaction");
1359
perror("sigaction");
2868
1360
return EX_OSERR;
2870
1362
if(old_sigterm_action.sa_handler != SIG_IGN){
2871
1363
ret = sigaction(SIGINT, &sigterm_action, NULL);
2873
perror_plus("sigaction");
1365
perror("sigaction");
2874
1366
exitcode = EX_OSERR;
2878
1370
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2880
perror_plus("sigaction");
1372
perror("sigaction");
2881
1373
return EX_OSERR;
2883
1375
if(old_sigterm_action.sa_handler != SIG_IGN){
2884
1376
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2886
perror_plus("sigaction");
1378
perror("sigaction");
2887
1379
exitcode = EX_OSERR;
2891
1383
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2893
perror_plus("sigaction");
1385
perror("sigaction");
2894
1386
return EX_OSERR;
2896
1388
if(old_sigterm_action.sa_handler != SIG_IGN){
2897
1389
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2899
perror_plus("sigaction");
1391
perror("sigaction");
2900
1392
exitcode = EX_OSERR;
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]);
1397
/* If the interface is down, bring it up */
1398
if(strcmp(interface, "none") != 0){
1399
if_index = (AvahiIfIndex) if_nametoindex(interface);
1401
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1402
exitcode = EX_UNAVAILABLE;
1410
/* Re-raise priviliges */
1418
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1419
messages about the network interface to mess up the prompt */
1420
ret = klogctl(8, NULL, 5);
1421
bool restore_loglevel = true;
1423
restore_loglevel = false;
1426
#endif /* __linux__ */
1428
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1431
exitcode = EX_OSERR;
1433
if(restore_loglevel){
1434
ret = klogctl(7, NULL, 0);
1439
#endif /* __linux__ */
1440
/* Lower privileges */
1448
strcpy(network.ifr_name, interface);
1449
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1451
perror("ioctl SIOCGIFFLAGS");
1453
if(restore_loglevel){
1454
ret = klogctl(7, NULL, 0);
1459
#endif /* __linux__ */
1460
exitcode = EX_OSERR;
1461
/* Lower privileges */
1469
if((network.ifr_flags & IFF_UP) == 0){
1470
network.ifr_flags |= IFF_UP;
1471
take_down_interface = true;
1472
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1474
take_down_interface = false;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1476
exitcode = EX_OSERR;
1478
if(restore_loglevel){
1479
ret = klogctl(7, NULL, 0);
1484
#endif /* __linux__ */
1485
/* Lower privileges */
1494
/* sleep checking until interface is running */
1495
for(int i=0; i < delay * 4; i++){
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_RUNNING){
1502
struct timespec sleeptime = { .tv_nsec = 250000000 };
1503
ret = nanosleep(&sleeptime, NULL);
1504
if(ret == -1 and errno != EINTR){
1505
perror("nanosleep");
1508
if(not take_down_interface){
1509
/* We won't need the socket anymore */
1510
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1516
if(restore_loglevel){
1517
/* Restores kernel loglevel to default */
1518
ret = klogctl(7, NULL, 0);
1523
#endif /* __linux__ */
1524
/* Lower privileges */
1526
if(take_down_interface){
1527
/* Lower privileges */
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,
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);
1533
/* Lower privileges permanently */
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"
1545
ret = init_gnutls_global(pubkey, seckey);
3002
fprintf_plus(stderr, "init_gnutls_global failed\n");
1547
fprintf(stderr, "init_gnutls_global failed\n");
3003
1548
exitcode = EX_UNAVAILABLE;
3205
1719
gpgme_release(mc.ctx);
3208
/* Cleans up the circular linked list of Mandos servers the client
3210
if(mc.current_server != NULL){
3211
mc.current_server->prev->next = NULL;
3212
while(mc.current_server != NULL){
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
3222
free(mc.current_server);
3223
mc.current_server = next;
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");
3322
/* Removes the GPGME temp directory and all files inside */
3323
if(tempdir != NULL){
3324
clean_dir_at(-1, tempdir, 0);
1722
/* Take down the network interface */
1723
if(take_down_interface){
1724
/* Re-raise priviliges */
1731
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1733
perror("ioctl SIOCGIFFLAGS");
1734
} else if(network.ifr_flags & IFF_UP) {
1735
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1736
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1745
/* Lower privileges permanently */
1754
/* Removes the temp directory used by GPGME */
1755
if(tempdir_created){
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1760
if(errno != ENOENT){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1769
/* Skip "." and ".." */
1770
if(direntry->d_name[0] == '.'
1771
and (direntry->d_name[1] == '\0'
1772
or (direntry->d_name[1] == '.'
1773
and direntry->d_name[2] == '\0'))){
1776
char *fullname = NULL;
1777
ret = asprintf(&fullname, "%s/%s", tempdir,
1783
ret = remove(fullname);
1785
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1792
ret = rmdir(tempdir);
1793
if(ret == -1 and errno != ENOENT){