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(),
139
122
#define PATHDIR "/conf/conf.d/mandos"
140
123
#define SECKEY "seckey.txt"
141
124
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
144
126
bool debug = false;
145
127
static const char mandos_protocol_version[] = "1";
146
128
const char *argp_program_version = "mandos-client " VERSION;
147
const char *argp_program_bug_address = "<mandos@recompile.se>";
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
148
130
static const char sys_class_net[] = "/sys/class/net";
149
131
char *connect_to = NULL;
150
const char *hookdir = HOOKDIR;
155
/* Doubly linked list that need to be circularly linked when used */
156
typedef struct server{
159
AvahiIfIndex if_index;
161
struct timespec last_seen;
166
133
/* Used for passing in values through the Avahi callback functions */
135
AvahiSimplePoll *simple_poll;
168
136
AvahiServer *server;
169
137
gnutls_certificate_credentials_t cred;
170
138
unsigned int dh_bits;
171
139
gnutls_dh_params_t dh_params;
172
140
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
177
142
} mandos_context;
179
/* global so signal handler can reach it*/
180
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" };
182
149
sig_atomic_t quit_now = 0;
183
150
int signal_received = 0;
185
/* Function to use when printing errors */
186
void perror_plus(const char *print_text){
188
fprintf(stderr, "Mandos plugin %s: ",
189
program_invocation_short_name);
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));
205
153
* Make additional room in "buffer" for at least BUFFER_SIZE more
206
154
* bytes. "buffer_capacity" is how much is currently allocated,
207
155
* "buffer_length" is how much is already used.
209
__attribute__((nonnull, warn_unused_result))
210
157
size_t incbuffer(char **buffer, size_t buffer_length,
211
size_t buffer_capacity){
158
size_t buffer_capacity){
212
159
if(buffer_length + BUFFER_SIZE > buffer_capacity){
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
222
164
buffer_capacity += BUFFER_SIZE;
224
166
return buffer_capacity;
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){
232
server *new_server = malloc(sizeof(server));
233
if(new_server == NULL){
234
perror_plus("malloc");
237
*new_server = (server){ .ip = strdup(ip),
239
.if_index = if_index,
241
if(new_server->ip == NULL){
242
perror_plus("strdup");
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){
262
new_server->next = new_server;
263
new_server->prev = new_server;
264
*current_server = new_server;
266
/* Place the new server last in the list */
267
new_server->next = *current_server;
268
new_server->prev = (*current_server)->prev;
269
new_server->prev->next = new_server;
270
(*current_server)->prev = new_server;
276
170
* Initialize GPGME.
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,
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
283
174
gpgme_error_t rc;
284
175
gpgme_engine_info_t engine_info;
287
179
* Helper function to insert pub and seckey to the engine keyring.
289
bool import_key(const char * const filename){
181
bool import_key(const char *filename){
292
184
gpgme_data_t pgp_data;
294
186
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
300
192
rc = gpgme_data_new_from_fd(&pgp_data, fd);
301
193
if(rc != GPG_ERR_NO_ERROR){
302
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
303
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));
307
rc = gpgme_op_import(mc->ctx, pgp_data);
199
rc = gpgme_op_import(mc.ctx, pgp_data);
308
200
if(rc != GPG_ERR_NO_ERROR){
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
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");
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
391
perror_plus("close");
393
210
gpgme_data_release(pgp_data);
398
fprintf_plus(stderr, "Initializing GPGME\n");
215
fprintf(stderr, "Initializing GPGME\n");
402
219
gpgme_check_version(NULL);
403
220
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
404
221
if(rc != GPG_ERR_NO_ERROR){
405
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
406
gpgme_strsource(rc), gpgme_strerror(rc));
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
410
/* Set GPGME home directory for the OpenPGP engine only */
227
/* Set GPGME home directory for the OpenPGP engine only */
411
228
rc = gpgme_get_engine_info(&engine_info);
412
229
if(rc != GPG_ERR_NO_ERROR){
413
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
414
gpgme_strsource(rc), gpgme_strerror(rc));
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
417
234
while(engine_info != NULL){
459
273
ssize_t plaintext_length = 0;
462
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
465
279
/* Create new GPGME data buffer from memory cryptotext */
466
280
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
468
282
if(rc != GPG_ERR_NO_ERROR){
469
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
470
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));
474
288
/* Create new empty GPGME data buffer for the plaintext */
475
289
rc = gpgme_data_new(&dh_plain);
476
290
if(rc != GPG_ERR_NO_ERROR){
477
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
478
gpgme_strsource(rc), gpgme_strerror(rc));
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
479
293
gpgme_data_release(dh_crypto);
483
297
/* Decrypt data from the cryptotext data buffer to the plaintext
485
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
486
300
if(rc != GPG_ERR_NO_ERROR){
487
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
488
gpgme_strsource(rc), gpgme_strerror(rc));
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
489
303
plaintext_length = -1;
491
305
gpgme_decrypt_result_t result;
492
result = gpgme_op_decrypt_result(mc->ctx);
306
result = gpgme_op_decrypt_result(mc.ctx);
493
307
if(result == NULL){
494
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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");
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
502
314
if(result->file_name != NULL){
503
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
fprintf(stderr, "File name: %s\n", result->file_name);
506
for(gpgme_recipient_t r = result->recipients; r != NULL;
508
fprintf_plus(stderr, "Public key algorithm: %s\n",
509
gpgme_pubkey_algo_name(r->pubkey_algo));
510
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
511
fprintf_plus(stderr, "Secret key available: %s\n",
512
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;
614
425
/* OpenPGP credentials */
615
ret = gnutls_certificate_allocate_credentials(&mc->cred);
426
gnutls_certificate_allocate_credentials(&mc.cred);
616
427
if(ret != GNUTLS_E_SUCCESS){
617
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
618
safer_gnutls_strerror(ret));
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
432
safer_gnutls_strerror(ret));
433
gnutls_global_deinit();
623
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
624
" secret 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,
629
443
ret = gnutls_certificate_set_openpgp_key_file
630
(mc->cred, pubkeyfilename, seckeyfilename,
444
(mc.cred, pubkeyfilename, seckeyfilename,
631
445
GNUTLS_OPENPGP_FMT_BASE64);
632
446
if(ret != GNUTLS_E_SUCCESS){
634
"Error[%d] while reading the OpenPGP key pair ('%s',"
635
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
636
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
637
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));
641
455
/* GnuTLS server initialization */
642
ret = gnutls_dh_params_init(&mc->dh_params);
643
if(ret != GNUTLS_E_SUCCESS){
644
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
645
" initialization: %s\n",
646
safer_gnutls_strerror(ret));
649
/* If a Diffie-Hellman parameters file was given, try to use it */
650
if(dhparamsfilename != NULL){
651
gnutls_datum_t params = { .data = NULL, .size = 0 };
653
int dhpfile = open(dhparamsfilename, O_RDONLY);
656
dhparamsfilename = NULL;
659
size_t params_capacity = 0;
661
params_capacity = incbuffer((char **)¶ms.data,
663
(size_t)params_capacity);
664
if(params_capacity == 0){
665
perror_plus("incbuffer");
668
dhparamsfilename = NULL;
671
ssize_t bytes_read = read(dhpfile,
672
params.data + params.size,
678
/* check bytes_read for failure */
683
dhparamsfilename = NULL;
686
params.size += (unsigned int)bytes_read;
688
ret = close(dhpfile);
690
perror_plus("close");
692
if(params.data == NULL){
693
dhparamsfilename = NULL;
695
if(dhparamsfilename == NULL){
698
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
699
GNUTLS_X509_FMT_PEM);
700
if(ret != GNUTLS_E_SUCCESS){
701
fprintf_plus(stderr, "Failed to parse DH parameters in file"
702
" \"%s\": %s\n", dhparamsfilename,
703
safer_gnutls_strerror(ret));
704
dhparamsfilename = NULL;
709
if(dhparamsfilename == NULL){
710
if(mc->dh_bits == 0){
711
/* Find out the optimal number of DH bits */
712
/* Try to read the private key file */
713
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
715
int secfile = open(seckeyfilename, O_RDONLY);
720
size_t buffer_capacity = 0;
722
buffer_capacity = incbuffer((char **)&buffer.data,
724
(size_t)buffer_capacity);
725
if(buffer_capacity == 0){
726
perror_plus("incbuffer");
731
ssize_t bytes_read = read(secfile,
732
buffer.data + buffer.size,
738
/* check bytes_read for failure */
745
buffer.size += (unsigned int)bytes_read;
749
/* If successful, use buffer to parse private key */
750
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
751
if(buffer.data != NULL){
753
gnutls_openpgp_privkey_t privkey = NULL;
754
ret = gnutls_openpgp_privkey_init(&privkey);
755
if(ret != GNUTLS_E_SUCCESS){
756
fprintf_plus(stderr, "Error initializing OpenPGP key"
758
safer_gnutls_strerror(ret));
762
ret = gnutls_openpgp_privkey_import
763
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
764
if(ret != GNUTLS_E_SUCCESS){
765
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
766
safer_gnutls_strerror(ret));
772
/* Use private key to suggest an appropriate
774
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
775
gnutls_openpgp_privkey_deinit(privkey);
777
fprintf_plus(stderr, "This OpenPGP key implies using"
778
" a GnuTLS security parameter \"%s\".\n",
779
safe_string(gnutls_sec_param_get_name
785
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
786
/* Err on the side of caution */
787
sec_param = GNUTLS_SEC_PARAM_ULTRA;
789
fprintf_plus(stderr, "Falling back to security parameter"
791
safe_string(gnutls_sec_param_get_name
796
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
800
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
801
" implies %u DH bits; using that.\n",
802
safe_string(gnutls_sec_param_get_name
807
fprintf_plus(stderr, "Failed to get implied number of DH"
808
" bits for security parameter \"%s\"): %s\n",
809
safe_string(gnutls_sec_param_get_name
811
safer_gnutls_strerror(ret));
815
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
818
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
819
if(ret != GNUTLS_E_SUCCESS){
820
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
821
" bits): %s\n", mc->dh_bits,
822
safer_gnutls_strerror(ret));
826
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);
832
gnutls_certificate_free_credentials(mc->cred);
833
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);
837
__attribute__((nonnull, warn_unused_result))
838
static int init_gnutls_session(gnutls_session_t *session,
481
static int init_gnutls_session(gnutls_session_t *session){
841
483
/* GnuTLS session creation */
894
537
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
895
538
__attribute__((unused)) const char *txt){}
897
/* Set effective uid to 0, return errno */
898
__attribute__((warn_unused_result))
899
int raise_privileges(void){
900
int old_errno = errno;
902
if(seteuid(0) == -1){
909
/* Set effective and real user ID to 0. Return errno. */
910
__attribute__((warn_unused_result))
911
int raise_privileges_permanently(void){
912
int old_errno = errno;
913
int ret = raise_privileges();
925
/* Set effective user ID to unprivileged saved user ID */
926
__attribute__((warn_unused_result))
927
int lower_privileges(void){
928
int old_errno = errno;
930
if(seteuid(uid) == -1){
937
/* Lower privileges permanently */
938
__attribute__((warn_unused_result))
939
int lower_privileges_permanently(void){
940
int old_errno = errno;
942
if(setuid(uid) == -1){
949
/* Helper function to add_local_route() and delete_local_route() */
950
__attribute__((nonnull, warn_unused_result))
951
static bool add_delete_local_route(const bool add,
953
AvahiIfIndex if_index){
955
char helper[] = "mandos-client-iprouteadddel";
956
char add_arg[] = "add";
957
char delete_arg[] = "delete";
958
char debug_flag[] = "--debug";
959
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
960
if(pluginhelperdir == NULL){
962
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
963
" variable not set; cannot run helper\n");
968
char interface[IF_NAMESIZE];
969
if(if_indextoname((unsigned int)if_index, interface) == NULL){
970
perror_plus("if_indextoname");
974
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
976
perror_plus("open(\"/dev/null\", O_RDONLY)");
982
/* Raise privileges */
983
errno = raise_privileges_permanently();
985
perror_plus("Failed to raise privileges");
986
/* _exit(EX_NOPERM); */
992
perror_plus("setgid");
995
/* Reset supplementary groups */
997
ret = setgroups(0, NULL);
999
perror_plus("setgroups");
1003
ret = dup2(devnull, STDIN_FILENO);
1005
perror_plus("dup2(devnull, STDIN_FILENO)");
1008
ret = close(devnull);
1010
perror_plus("close");
1013
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1015
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1018
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1023
if(helperdir_fd == -1){
1024
perror_plus("open");
1025
_exit(EX_UNAVAILABLE);
1027
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1029
if(helper_fd == -1){
1030
perror_plus("openat");
1031
close(helperdir_fd);
1032
_exit(EX_UNAVAILABLE);
1034
close(helperdir_fd);
1036
#pragma GCC diagnostic push
1037
#pragma GCC diagnostic ignored "-Wcast-qual"
1039
if(fexecve(helper_fd, (char *const [])
1040
{ helper, add ? add_arg : delete_arg, (char *)address,
1041
interface, debug ? debug_flag : NULL, NULL },
1044
#pragma GCC diagnostic pop
1046
perror_plus("fexecve");
1047
_exit(EXIT_FAILURE);
1051
perror_plus("fork");
1058
pret = waitpid(pid, &status, 0);
1059
if(pret == -1 and errno == EINTR and quit_now){
1060
int errno_raising = 0;
1061
if((errno = raise_privileges()) != 0){
1062
errno_raising = errno;
1063
perror_plus("Failed to raise privileges in order to"
1064
" kill helper program");
1066
if(kill(pid, SIGTERM) == -1){
1067
perror_plus("kill");
1069
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1070
perror_plus("Failed to lower privileges after killing"
1075
} while(pret == -1 and errno == EINTR);
1077
perror_plus("waitpid");
1080
if(WIFEXITED(status)){
1081
if(WEXITSTATUS(status) != 0){
1082
fprintf_plus(stderr, "Error: iprouteadddel exited"
1083
" with status %d\n", WEXITSTATUS(status));
1088
if(WIFSIGNALED(status)){
1089
fprintf_plus(stderr, "Error: iprouteadddel died by"
1090
" signal %d\n", WTERMSIG(status));
1093
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1097
__attribute__((nonnull, warn_unused_result))
1098
static bool add_local_route(const char *address,
1099
AvahiIfIndex if_index){
1101
fprintf_plus(stderr, "Adding route to %s\n", address);
1103
return add_delete_local_route(true, address, if_index);
1106
__attribute__((nonnull, warn_unused_result))
1107
static bool delete_local_route(const char *address,
1108
AvahiIfIndex if_index){
1110
fprintf_plus(stderr, "Removing route to %s\n", address);
1112
return add_delete_local_route(false, address, if_index);
1115
540
/* Called when a Mandos server is found */
1116
__attribute__((nonnull, warn_unused_result))
1117
static int start_mandos_communication(const char *ip, in_port_t port,
541
static int start_mandos_communication(const char *ip, uint16_t port,
1118
542
AvahiIfIndex if_index,
1119
int af, mandos_context *mc){
1120
544
int ret, tcp_sd = -1;
1122
struct sockaddr_storage to;
547
struct sockaddr_in in;
548
struct sockaddr_in6 in6;
1123
550
char *buffer = NULL;
1124
551
char *decrypted_buffer = NULL;
1125
552
size_t buffer_length = 0;
1253
651
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1254
652
char interface[IF_NAMESIZE];
1255
653
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1256
perror_plus("if_indextoname");
654
perror("if_indextoname");
1258
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1259
"\n", ip, interface, (uintmax_t)port);
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
1262
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1263
ip, (uintmax_t)port);
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1265
663
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1266
664
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1268
ret = getnameinfo((struct sockaddr *)&to,
1269
sizeof(struct sockaddr_in6),
1270
addrstr, sizeof(addrstr), NULL, 0,
1273
ret = getnameinfo((struct sockaddr *)&to,
1274
sizeof(struct sockaddr_in),
1275
addrstr, sizeof(addrstr), NULL, 0,
1278
if(ret == EAI_SYSTEM){
1279
perror_plus("getnameinfo");
1280
} else if(ret != 0) {
1281
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1282
} else if(strcmp(addrstr, ip) != 0){
1283
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1294
ret = connect(tcp_sd, (struct sockaddr *)&to,
1295
sizeof(struct sockaddr_in6));
1297
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1298
sizeof(struct sockaddr_in));
1301
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1302
and if_index != AVAHI_IF_UNSPEC
1303
and connect_to == NULL
1304
and not route_added and
1305
((af == AF_INET6 and not
1306
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1308
or (af == AF_INET and
1309
/* Not a a IPv4LL address */
1310
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1311
& 0xFFFF0000L) != 0xA9FE0000L))){
1312
/* Work around Avahi bug - Avahi does not announce link-local
1313
addresses if it has a global address, so local hosts with
1314
*only* a link-local address (e.g. Mandos clients) cannot
1315
connect to a Mandos server announced by Avahi on a server
1316
host with a global address. Work around this by retrying
1317
with an explicit route added with the server's address.
1319
Avahi bug reference:
1320
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1321
https://bugs.debian.org/587961
1324
fprintf_plus(stderr, "Mandos server unreachable, trying"
1328
route_added = add_local_route(ip, if_index);
1334
if(errno != ECONNREFUSED or debug){
1336
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){
1349
706
const char *out = mandos_protocol_version;
1704
1019
signal_received = sig;
1705
1020
int old_errno = errno;
1706
/* set main loop to exit */
1707
if(simple_poll != NULL){
1708
avahi_simple_poll_quit(simple_poll);
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1710
1024
errno = old_errno;
1713
__attribute__((nonnull, warn_unused_result))
1714
bool get_flags(const char *ifname, struct ifreq *ifr){
1718
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1721
perror_plus("socket");
1725
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1726
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1727
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1731
perror_plus("ioctl SIOCGIFFLAGS");
1734
if((close(s) == -1) and debug){
1736
perror_plus("close");
1741
if((close(s) == -1) and debug){
1743
perror_plus("close");
1749
__attribute__((nonnull, warn_unused_result))
1750
bool good_flags(const char *ifname, const struct ifreq *ifr){
1752
/* Reject the loopback device */
1753
if(ifr->ifr_flags & IFF_LOOPBACK){
1755
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1760
/* Accept point-to-point devices only if connect_to is specified */
1761
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1763
fprintf_plus(stderr, "Accepting point-to-point interface"
1764
" \"%s\"\n", ifname);
1768
/* Otherwise, reject non-broadcast-capable devices */
1769
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1771
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1772
" \"%s\"\n", ifname);
1776
/* Reject non-ARP interfaces (including dummy interfaces) */
1777
if(ifr->ifr_flags & IFF_NOARP){
1779
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1785
/* Accept this device */
1787
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1793
1028
* This function determines if a directory entry in /sys/class/net
1794
1029
* corresponds to an acceptable network device.
1795
1030
* (This function is passed to scandir(3) as a filter function.)
1797
__attribute__((nonnull, warn_unused_result))
1798
1032
int good_interface(const struct dirent *if_entry){
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1799
1041
if(if_entry->d_name[0] == '.'){
1804
if(not get_flags(if_entry->d_name, &ifr)){
1806
fprintf_plus(stderr, "Failed to get flags for interface "
1807
"\"%s\"\n", if_entry->d_name);
1812
if(not good_flags(if_entry->d_name, &ifr)){
1819
* This function determines if a network interface is up.
1821
__attribute__((nonnull, warn_unused_result))
1822
bool interface_is_up(const char *interface){
1824
if(not get_flags(interface, &ifr)){
1826
fprintf_plus(stderr, "Failed to get flags for interface "
1827
"\"%s\"\n", interface);
1832
return (bool)(ifr.ifr_flags & IFF_UP);
1836
* This function determines if a network interface is running
1838
__attribute__((nonnull, warn_unused_result))
1839
bool interface_is_running(const char *interface){
1841
if(not get_flags(interface, &ifr)){
1843
fprintf_plus(stderr, "Failed to get flags for interface "
1844
"\"%s\"\n", interface);
1849
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1852
__attribute__((nonnull, pure, warn_unused_result))
1853
int notdotentries(const struct dirent *direntry){
1854
/* Skip "." and ".." */
1855
if(direntry->d_name[0] == '.'
1856
and (direntry->d_name[1] == '\0'
1857
or (direntry->d_name[1] == '.'
1858
and direntry->d_name[2] == '\0'))){
1864
/* Is this directory entry a runnable program? */
1865
__attribute__((nonnull, warn_unused_result))
1866
int runnable_hook(const struct dirent *direntry){
1871
if((direntry->d_name)[0] == '\0'){
1876
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1877
"abcdefghijklmnopqrstuvwxyz"
1880
if((direntry->d_name)[sret] != '\0'){
1881
/* Contains non-allowed characters */
1883
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1889
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1892
perror_plus("Could not stat hook");
1896
if(not (S_ISREG(st.st_mode))){
1897
/* Not a regular file */
1899
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1904
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1905
/* Not executable */
1907
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 */
1913
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1919
__attribute__((nonnull, warn_unused_result))
1920
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1921
mandos_context *mc){
1923
struct timespec now;
1924
struct timespec waited_time;
1925
intmax_t block_time;
1928
if(mc->current_server == NULL){
1930
fprintf_plus(stderr, "Wait until first server is found."
1933
ret = avahi_simple_poll_iterate(s, -1);
1936
fprintf_plus(stderr, "Check current_server if we should run"
1939
/* the current time */
1940
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1942
perror_plus("clock_gettime");
1945
/* Calculating in ms how long time between now and server
1946
who we visted longest time ago. Now - last seen. */
1947
waited_time.tv_sec = (now.tv_sec
1948
- mc->current_server->last_seen.tv_sec);
1949
waited_time.tv_nsec = (now.tv_nsec
1950
- mc->current_server->last_seen.tv_nsec);
1951
/* total time is 10s/10,000ms.
1952
Converting to s from ms by dividing by 1,000,
1953
and ns to ms by dividing by 1,000,000. */
1954
block_time = ((retry_interval
1955
- ((intmax_t)waited_time.tv_sec * 1000))
1956
- ((intmax_t)waited_time.tv_nsec / 1000000));
1959
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1963
if(block_time <= 0){
1964
ret = start_mandos_communication(mc->current_server->ip,
1965
mc->current_server->port,
1966
mc->current_server->if_index,
1967
mc->current_server->af, mc);
1969
avahi_simple_poll_quit(s);
1972
ret = clock_gettime(CLOCK_MONOTONIC,
1973
&mc->current_server->last_seen);
1975
perror_plus("clock_gettime");
1978
mc->current_server = mc->current_server->next;
1979
block_time = 0; /* Call avahi to find new Mandos
1980
servers, but don't block */
1983
ret = avahi_simple_poll_iterate(s, (int)block_time);
1986
if(ret > 0 or errno != EINTR){
1987
return (ret != 1) ? ret : 0;
1993
__attribute__((nonnull))
1994
void run_network_hooks(const char *mode, const char *interface,
1996
struct dirent **direntries = NULL;
1997
if(hookdir_fd == -1){
1998
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2000
if(hookdir_fd == -1){
2001
if(errno == ENOENT){
2003
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2004
" found\n", hookdir);
2007
perror_plus("open");
2012
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2014
perror_plus("open(\"/dev/null\", O_RDONLY)");
2017
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2018
runnable_hook, alphasort);
2020
perror_plus("scandir");
2024
struct dirent *direntry;
2026
for(int i = 0; i < numhooks; i++){
2027
direntry = direntries[i];
2029
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2032
pid_t hook_pid = fork();
2035
/* Raise privileges */
2036
errno = raise_privileges_permanently();
2038
perror_plus("Failed to raise privileges");
2045
perror_plus("setgid");
2048
/* Reset supplementary groups */
2050
ret = setgroups(0, NULL);
2052
perror_plus("setgroups");
2055
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2057
perror_plus("setenv");
2060
ret = setenv("DEVICE", interface, 1);
2062
perror_plus("setenv");
2065
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2067
perror_plus("setenv");
2070
ret = setenv("MODE", mode, 1);
2072
perror_plus("setenv");
2076
ret = asprintf(&delaystring, "%f", (double)delay);
2078
perror_plus("asprintf");
2081
ret = setenv("DELAY", delaystring, 1);
2084
perror_plus("setenv");
2088
if(connect_to != NULL){
2089
ret = setenv("CONNECT", connect_to, 1);
2091
perror_plus("setenv");
2095
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2099
perror_plus("openat");
2100
_exit(EXIT_FAILURE);
2102
if(close(hookdir_fd) == -1){
2103
perror_plus("close");
2104
_exit(EXIT_FAILURE);
2106
ret = dup2(devnull, STDIN_FILENO);
2108
perror_plus("dup2(devnull, STDIN_FILENO)");
2111
ret = close(devnull);
2113
perror_plus("close");
2116
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2118
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2121
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2123
perror_plus("fexecve");
2124
_exit(EXIT_FAILURE);
2128
perror_plus("fork");
2133
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2134
perror_plus("waitpid");
2138
if(WIFEXITED(status)){
2139
if(WEXITSTATUS(status) != 0){
2140
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2141
" with status %d\n", direntry->d_name,
2142
WEXITSTATUS(status));
2146
} else if(WIFSIGNALED(status)){
2147
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2148
" signal %d\n", direntry->d_name,
2153
fprintf_plus(stderr, "Warning: network hook \"%s\""
2154
" crashed\n", direntry->d_name);
2160
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2166
if(close(hookdir_fd) == -1){
2167
perror_plus("close");
2174
__attribute__((nonnull, warn_unused_result))
2175
int bring_up_interface(const char *const interface,
2177
int old_errno = errno;
2179
struct ifreq network;
2180
unsigned int if_index = if_nametoindex(interface);
2182
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2192
if(not interface_is_up(interface)){
2194
int ioctl_errno = 0;
2195
if(not get_flags(interface, &network)){
2197
fprintf_plus(stderr, "Failed to get flags for interface "
2198
"\"%s\"\n", interface);
2202
network.ifr_flags |= IFF_UP; /* set flag */
2204
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2207
perror_plus("socket");
2215
perror_plus("close");
2222
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2226
/* Raise privileges */
2227
ret_errno = raise_privileges();
2230
perror_plus("Failed to raise privileges");
2235
bool restore_loglevel = false;
2237
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2238
messages about the network interface to mess up the prompt */
2239
ret_linux = klogctl(8, NULL, 5);
2240
if(ret_linux == -1){
2241
perror_plus("klogctl");
2243
restore_loglevel = true;
2246
#endif /* __linux__ */
2247
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2248
ioctl_errno = errno;
2250
if(restore_loglevel){
2251
ret_linux = klogctl(7, NULL, 0);
2252
if(ret_linux == -1){
2253
perror_plus("klogctl");
2256
#endif /* __linux__ */
2258
/* If raise_privileges() succeeded above */
2260
/* Lower privileges */
2261
ret_errno = lower_privileges();
2264
perror_plus("Failed to lower privileges");
2268
/* Close the socket */
2271
perror_plus("close");
2274
if(ret_setflags == -1){
2275
errno = ioctl_errno;
2276
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2281
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2285
/* Sleep checking until interface is running.
2286
Check every 0.25s, up to total time of delay */
2287
for(int i = 0; i < delay * 4; i++){
2288
if(interface_is_running(interface)){
2291
struct timespec sleeptime = { .tv_nsec = 250000000 };
2292
ret = nanosleep(&sleeptime, NULL);
2293
if(ret == -1 and errno != EINTR){
2294
perror_plus("nanosleep");
2302
__attribute__((nonnull, warn_unused_result))
2303
int take_down_interface(const char *const interface){
2304
int old_errno = errno;
2305
struct ifreq network;
2306
unsigned int if_index = if_nametoindex(interface);
2308
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2312
if(interface_is_up(interface)){
2314
int ioctl_errno = 0;
2315
if(not get_flags(interface, &network) and debug){
2317
fprintf_plus(stderr, "Failed to get flags for interface "
2318
"\"%s\"\n", interface);
2322
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2324
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2327
perror_plus("socket");
2333
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2337
/* Raise privileges */
2338
ret_errno = raise_privileges();
2341
perror_plus("Failed to raise privileges");
2344
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2345
ioctl_errno = errno;
2347
/* If raise_privileges() succeeded above */
2349
/* Lower privileges */
2350
ret_errno = lower_privileges();
2353
perror_plus("Failed to lower privileges");
2357
/* Close the socket */
2358
int ret = close(sd);
2360
perror_plus("close");
2363
if(ret_setflags == -1){
2364
errno = ioctl_errno;
2365
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2370
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2378
1122
int main(int argc, char *argv[]){
2379
mandos_context mc = { .server = NULL, .dh_bits = 0,
2380
.priority = "SECURE256:!CTYPE-X.509"
2381
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2382
.current_server = NULL, .interfaces = NULL,
2383
.interfaces_size = 0 };
2384
1123
AvahiSServiceBrowser *sb = NULL;
2387
1126
intmax_t tmpmax;
2389
1128
int exitcode = EXIT_SUCCESS;
2390
char *interfaces_to_take_down = NULL;
2391
size_t interfaces_to_take_down_size = 0;
2392
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2393
char old_tempdir[] = "/tmp/mandosXXXXXX";
2394
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;
2395
1137
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2396
1138
const char *seckey = PATHDIR "/" SECKEY;
2397
1139
const char *pubkey = PATHDIR "/" PUBKEY;
2398
const char *dh_params_file = NULL;
2399
char *interfaces_hooks = NULL;
2401
1141
bool gnutls_initialized = false;
2402
1142
bool gpgme_initialized = false;
2403
1143
float delay = 2.5f;
2404
double retry_interval = 10; /* 10s between trying a server and
2405
retrying the same server again */
2407
1145
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2408
1146
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2588
/* Work around Debian bug #633582:
2589
<https://bugs.debian.org/633582> */
2591
/* Re-raise privileges */
2592
ret = raise_privileges();
2595
perror_plus("Failed to raise privileges");
2599
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2600
int seckey_fd = open(seckey, O_RDONLY);
2601
if(seckey_fd == -1){
2602
perror_plus("open");
2604
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2606
perror_plus("fstat");
2608
if(S_ISREG(st.st_mode)
2609
and st.st_uid == 0 and st.st_gid == 0){
2610
ret = fchown(seckey_fd, uid, gid);
2612
perror_plus("fchown");
2620
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2621
int pubkey_fd = open(pubkey, O_RDONLY);
2622
if(pubkey_fd == -1){
2623
perror_plus("open");
2625
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2627
perror_plus("fstat");
2629
if(S_ISREG(st.st_mode)
2630
and st.st_uid == 0 and st.st_gid == 0){
2631
ret = fchown(pubkey_fd, uid, gid);
2633
perror_plus("fchown");
2641
if(dh_params_file != NULL
2642
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2643
int dhparams_fd = open(dh_params_file, O_RDONLY);
2644
if(dhparams_fd == -1){
2645
perror_plus("open");
2647
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2649
perror_plus("fstat");
2651
if(S_ISREG(st.st_mode)
2652
and st.st_uid == 0 and st.st_gid == 0){
2653
ret = fchown(dhparams_fd, uid, gid);
2655
perror_plus("fchown");
2663
/* Lower privileges */
2664
ret = lower_privileges();
2667
perror_plus("Failed to lower privileges");
2672
/* Remove invalid interface names (except "none") */
2674
char *interface = NULL;
2675
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2677
if(strcmp(interface, "none") != 0
2678
and if_nametoindex(interface) == 0){
2679
if(interface[0] != '\0'){
2680
fprintf_plus(stderr, "Not using nonexisting interface"
2681
" \"%s\"\n", interface);
2683
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2689
/* Run network hooks */
2691
if(mc.interfaces != NULL){
2692
interfaces_hooks = malloc(mc.interfaces_size);
2693
if(interfaces_hooks == NULL){
2694
perror_plus("malloc");
2697
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2698
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2700
run_network_hooks("start", interfaces_hooks != NULL ?
2701
interfaces_hooks : "", delay);
2705
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;
2708
1323
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2709
1324
from the signal handler */
2710
1325
/* Initialize the pseudo-RNG for Avahi */
2711
1326
srand((unsigned int) time(NULL));
2712
simple_poll = avahi_simple_poll_new();
2713
if(simple_poll == NULL){
2714
fprintf_plus(stderr,
2715
"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");
2716
1330
exitcode = EX_UNAVAILABLE;
2743
1357
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2745
perror_plus("sigaction");
1359
perror("sigaction");
2746
1360
return EX_OSERR;
2748
1362
if(old_sigterm_action.sa_handler != SIG_IGN){
2749
1363
ret = sigaction(SIGINT, &sigterm_action, NULL);
2751
perror_plus("sigaction");
1365
perror("sigaction");
2752
1366
exitcode = EX_OSERR;
2756
1370
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2758
perror_plus("sigaction");
1372
perror("sigaction");
2759
1373
return EX_OSERR;
2761
1375
if(old_sigterm_action.sa_handler != SIG_IGN){
2762
1376
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2764
perror_plus("sigaction");
1378
perror("sigaction");
2765
1379
exitcode = EX_OSERR;
2769
1383
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2771
perror_plus("sigaction");
1385
perror("sigaction");
2772
1386
return EX_OSERR;
2774
1388
if(old_sigterm_action.sa_handler != SIG_IGN){
2775
1389
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2777
perror_plus("sigaction");
1391
perror("sigaction");
2778
1392
exitcode = EX_OSERR;
2783
/* If no interfaces were specified, make a list */
2784
if(mc.interfaces == NULL){
2785
struct dirent **direntries = NULL;
2786
/* Look for any good interfaces */
2787
ret = scandir(sys_class_net, &direntries, good_interface,
2790
/* Add all found interfaces to interfaces list */
2791
for(int i = 0; i < ret; ++i){
2792
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2793
direntries[i]->d_name);
2796
perror_plus("argz_add");
2797
free(direntries[i]);
2801
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2802
direntries[i]->d_name);
2804
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 */
2811
fprintf_plus(stderr, "Could not find a network interface\n");
2812
exitcode = EXIT_FAILURE;
2817
/* Bring up interfaces which are down, and remove any "none"s */
2819
char *interface = NULL;
2820
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2822
/* If interface name is "none", stop bringing up interfaces.
2823
Also remove all instances of "none" from the list */
2824
if(strcmp(interface, "none") == 0){
2825
argz_delete(&mc.interfaces, &mc.interfaces_size,
2828
while((interface = argz_next(mc.interfaces,
2829
mc.interfaces_size, interface))){
2830
if(strcmp(interface, "none") == 0){
2831
argz_delete(&mc.interfaces, &mc.interfaces_size,
2838
bool interface_was_up = interface_is_up(interface);
2839
errno = bring_up_interface(interface, delay);
2840
if(not interface_was_up){
2842
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2843
" %s\n", interface, strerror(errno));
2845
errno = argz_add(&interfaces_to_take_down,
2846
&interfaces_to_take_down_size,
2849
perror_plus("argz_add");
2854
if(debug and (interfaces_to_take_down == NULL)){
2855
fprintf_plus(stderr, "No interfaces were brought up\n");
2859
/* If we only got one interface, explicitly use only that one */
2860
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2862
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2865
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1533
/* Lower privileges permanently */
2872
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1545
ret = init_gnutls_global(pubkey, seckey);
2874
fprintf_plus(stderr, "init_gnutls_global failed\n");
1547
fprintf(stderr, "init_gnutls_global failed\n");
2875
1548
exitcode = EX_UNAVAILABLE;
3077
1719
gpgme_release(mc.ctx);
3080
/* Cleans up the circular linked list of Mandos servers the client
3082
if(mc.current_server != NULL){
3083
mc.current_server->prev->next = NULL;
3084
while(mc.current_server != NULL){
3085
server *next = mc.current_server->next;
3087
#pragma GCC diagnostic push
3088
#pragma GCC diagnostic ignored "-Wcast-qual"
3090
free((char *)(mc.current_server->ip));
3092
#pragma GCC diagnostic pop
3094
free(mc.current_server);
3095
mc.current_server = next;
3099
/* Re-raise privileges */
3101
ret = raise_privileges();
3104
perror_plus("Failed to raise privileges");
3107
/* Run network hooks */
3108
run_network_hooks("stop", interfaces_hooks != NULL ?
3109
interfaces_hooks : "", delay);
3111
/* Take down the network interfaces which were brought up */
3113
char *interface = NULL;
3114
while((interface = argz_next(interfaces_to_take_down,
3115
interfaces_to_take_down_size,
3117
ret = take_down_interface(interface);
3120
perror_plus("Failed to take down interface");
3123
if(debug and (interfaces_to_take_down == NULL)){
3124
fprintf_plus(stderr, "No interfaces needed to be taken"
3130
ret = lower_privileges_permanently();
3133
perror_plus("Failed to lower privileges permanently");
3137
free(interfaces_to_take_down);
3138
free(interfaces_hooks);
3140
void clean_dir_at(int base, const char * const dirname,
3142
struct dirent **direntries = NULL;
3144
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3150
perror_plus("open");
3153
int numentries = scandirat(dir_fd, ".", &direntries,
3154
notdotentries, alphasort);
3155
if(numentries >= 0){
3156
for(int i = 0; i < numentries; i++){
3158
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3159
dirname, direntries[i]->d_name);
3161
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3163
if(errno == EISDIR){
3164
dret = unlinkat(dir_fd, direntries[i]->d_name,
3167
if((dret == -1) and (errno == ENOTEMPTY)
3168
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3169
== 0) and (level == 0)){
3170
/* Recurse only in this special case */
3171
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3174
if((dret == -1) and (errno != ENOENT)){
3175
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3176
direntries[i]->d_name, strerror(errno));
3179
free(direntries[i]);
3182
/* need to clean even if 0 because man page doesn't specify */
3184
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3185
if(dret == -1 and errno != ENOENT){
3186
perror_plus("rmdir");
3189
perror_plus("scandirat");
3194
/* Removes the GPGME temp directory and all files inside */
3195
if(tempdir != NULL){
3196
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){