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 © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 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
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
srand(), 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 */
73
#include <time.h> /* nanosleep(), time(), sleep() */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
74
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
75
68
SIOCSIFFLAGS, if_indextoname(),
76
69
if_nametoindex(), IF_NAMESIZE */
139
120
#define PATHDIR "/conf/conf.d/mandos"
140
121
#define SECKEY "seckey.txt"
141
122
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
144
124
bool debug = false;
145
125
static const char mandos_protocol_version[] = "1";
146
126
const char *argp_program_version = "mandos-client " VERSION;
147
const char *argp_program_bug_address = "<mandos@recompile.se>";
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
148
128
static const char sys_class_net[] = "/sys/class/net";
149
129
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
131
/* Used for passing in values through the Avahi callback functions */
133
AvahiSimplePoll *simple_poll;
168
134
AvahiServer *server;
169
135
gnutls_certificate_credentials_t cred;
170
136
unsigned int dh_bits;
171
137
gnutls_dh_params_t dh_params;
172
138
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
177
140
} mandos_context;
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
142
/* global context so signal handler can reach it*/
143
mandos_context mc = { .simple_poll = NULL, .server = NULL,
144
.dh_bits = 1024, .priority = "SECURE256"
145
":!CTYPE-X.509:+CTYPE-OPENPGP" };
182
147
sig_atomic_t quit_now = 0;
183
148
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
151
* Make additional room in "buffer" for at least BUFFER_SIZE more
206
152
* bytes. "buffer_capacity" is how much is currently allocated,
207
153
* "buffer_length" is how much is already used.
209
__attribute__((nonnull, warn_unused_result))
210
155
size_t incbuffer(char **buffer, size_t buffer_length,
211
size_t buffer_capacity){
156
size_t buffer_capacity){
212
157
if(buffer_length + BUFFER_SIZE > buffer_capacity){
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
158
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
222
162
buffer_capacity += BUFFER_SIZE;
224
164
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
168
* 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,
170
static bool init_gpgme(const char *seckey,
171
const char *pubkey, const char *tempdir){
283
172
gpgme_error_t rc;
284
173
gpgme_engine_info_t engine_info;
287
177
* Helper function to insert pub and seckey to the engine keyring.
289
bool import_key(const char * const filename){
179
bool import_key(const char *filename){
292
182
gpgme_data_t pgp_data;
294
184
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
300
190
rc = gpgme_data_new_from_fd(&pgp_data, fd);
301
191
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));
192
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
193
gpgme_strsource(rc), gpgme_strerror(rc));
307
rc = gpgme_op_import(mc->ctx, pgp_data);
197
rc = gpgme_op_import(mc.ctx, pgp_data);
308
198
if(rc != GPG_ERR_NO_ERROR){
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
199
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
200
gpgme_strsource(rc), gpgme_strerror(rc));
204
ret = (int)TEMP_FAILURE_RETRY(close(fd));
316
perror_plus("close");
318
208
gpgme_data_release(pgp_data);
323
fprintf_plus(stderr, "Initializing GPGME\n");
213
fprintf(stderr, "Initializing GPGME\n");
327
217
gpgme_check_version(NULL);
328
218
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
329
219
if(rc != GPG_ERR_NO_ERROR){
330
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
331
gpgme_strsource(rc), gpgme_strerror(rc));
220
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
221
gpgme_strsource(rc), gpgme_strerror(rc));
335
/* Set GPGME home directory for the OpenPGP engine only */
225
/* Set GPGME home directory for the OpenPGP engine only */
336
226
rc = gpgme_get_engine_info(&engine_info);
337
227
if(rc != GPG_ERR_NO_ERROR){
338
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
339
gpgme_strsource(rc), gpgme_strerror(rc));
228
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
229
gpgme_strsource(rc), gpgme_strerror(rc));
342
232
while(engine_info != NULL){
384
271
ssize_t plaintext_length = 0;
387
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
274
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
390
277
/* Create new GPGME data buffer from memory cryptotext */
391
278
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
393
280
if(rc != GPG_ERR_NO_ERROR){
394
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
395
gpgme_strsource(rc), gpgme_strerror(rc));
281
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
282
gpgme_strsource(rc), gpgme_strerror(rc));
399
286
/* Create new empty GPGME data buffer for the plaintext */
400
287
rc = gpgme_data_new(&dh_plain);
401
288
if(rc != GPG_ERR_NO_ERROR){
402
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
403
gpgme_strsource(rc), gpgme_strerror(rc));
289
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
290
gpgme_strsource(rc), gpgme_strerror(rc));
404
291
gpgme_data_release(dh_crypto);
408
295
/* Decrypt data from the cryptotext data buffer to the plaintext
410
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
297
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
411
298
if(rc != GPG_ERR_NO_ERROR){
412
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
299
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
414
301
plaintext_length = -1;
416
303
gpgme_decrypt_result_t result;
417
result = gpgme_op_decrypt_result(mc->ctx);
304
result = gpgme_op_decrypt_result(mc.ctx);
418
305
if(result == NULL){
419
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
306
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
421
if(result->unsupported_algorithm != NULL) {
422
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
423
result->unsupported_algorithm);
425
fprintf_plus(stderr, "Wrong key usage: %s\n",
426
result->wrong_key_usage ? "Yes" : "No");
308
fprintf(stderr, "Unsupported algorithm: %s\n",
309
result->unsupported_algorithm);
310
fprintf(stderr, "Wrong key usage: %u\n",
311
result->wrong_key_usage);
427
312
if(result->file_name != NULL){
428
fprintf_plus(stderr, "File name: %s\n", result->file_name);
313
fprintf(stderr, "File name: %s\n", result->file_name);
430
315
gpgme_recipient_t recipient;
431
316
recipient = result->recipients;
432
317
while(recipient != NULL){
433
fprintf_plus(stderr, "Public key algorithm: %s\n",
434
gpgme_pubkey_algo_name
435
(recipient->pubkey_algo));
436
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
437
fprintf_plus(stderr, "Secret key available: %s\n",
438
recipient->status == GPG_ERR_NO_SECKEY
318
fprintf(stderr, "Public key algorithm: %s\n",
319
gpgme_pubkey_algo_name(recipient->pubkey_algo));
320
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
321
fprintf(stderr, "Secret key available: %s\n",
322
recipient->status == GPG_ERR_NO_SECKEY
440
324
recipient = recipient->next;
542
423
/* OpenPGP credentials */
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
424
gnutls_certificate_allocate_credentials(&mc.cred);
544
425
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
546
safer_gnutls_strerror(ret));
426
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
430
safer_gnutls_strerror(ret));
431
gnutls_global_deinit();
551
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
552
" secret key %s as GnuTLS credentials\n",
436
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
437
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
557
441
ret = gnutls_certificate_set_openpgp_key_file
558
(mc->cred, pubkeyfilename, seckeyfilename,
442
(mc.cred, pubkeyfilename, seckeyfilename,
559
443
GNUTLS_OPENPGP_FMT_BASE64);
560
444
if(ret != GNUTLS_E_SUCCESS){
562
"Error[%d] while reading the OpenPGP key pair ('%s',"
563
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
564
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
565
safer_gnutls_strerror(ret));
446
"Error[%d] while reading the OpenPGP key pair ('%s',"
447
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
448
fprintf(stderr, "The GnuTLS error is: %s\n",
449
safer_gnutls_strerror(ret));
569
453
/* GnuTLS server initialization */
570
ret = gnutls_dh_params_init(&mc->dh_params);
571
if(ret != GNUTLS_E_SUCCESS){
572
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
573
" initialization: %s\n",
574
safer_gnutls_strerror(ret));
577
/* If a Diffie-Hellman parameters file was given, try to use it */
578
if(dhparamsfilename != NULL){
579
gnutls_datum_t params = { .data = NULL, .size = 0 };
581
int dhpfile = open(dhparamsfilename, O_RDONLY);
584
dhparamsfilename = NULL;
587
size_t params_capacity = 0;
589
params_capacity = incbuffer((char **)¶ms.data,
591
(size_t)params_capacity);
592
if(params_capacity == 0){
593
perror_plus("incbuffer");
596
dhparamsfilename = NULL;
599
ssize_t bytes_read = read(dhpfile,
600
params.data + params.size,
606
/* check bytes_read for failure */
611
dhparamsfilename = NULL;
614
params.size += (unsigned int)bytes_read;
616
ret = close(dhpfile);
618
perror_plus("close");
620
if(params.data == NULL){
621
dhparamsfilename = NULL;
623
if(dhparamsfilename == NULL){
626
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
627
GNUTLS_X509_FMT_PEM);
628
if(ret != GNUTLS_E_SUCCESS){
629
fprintf_plus(stderr, "Failed to parse DH parameters in file"
630
" \"%s\": %s\n", dhparamsfilename,
631
safer_gnutls_strerror(ret));
632
dhparamsfilename = NULL;
637
if(dhparamsfilename == NULL){
638
if(mc->dh_bits == 0){
639
/* Find out the optimal number of DH bits */
640
/* Try to read the private key file */
641
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
643
int secfile = open(seckeyfilename, O_RDONLY);
648
size_t buffer_capacity = 0;
650
buffer_capacity = incbuffer((char **)&buffer.data,
652
(size_t)buffer_capacity);
653
if(buffer_capacity == 0){
654
perror_plus("incbuffer");
659
ssize_t bytes_read = read(secfile,
660
buffer.data + buffer.size,
666
/* check bytes_read for failure */
673
buffer.size += (unsigned int)bytes_read;
677
/* If successful, use buffer to parse private key */
678
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
679
if(buffer.data != NULL){
681
gnutls_openpgp_privkey_t privkey = NULL;
682
ret = gnutls_openpgp_privkey_init(&privkey);
683
if(ret != GNUTLS_E_SUCCESS){
684
fprintf_plus(stderr, "Error initializing OpenPGP key"
686
safer_gnutls_strerror(ret));
690
ret = gnutls_openpgp_privkey_import
691
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
692
if(ret != GNUTLS_E_SUCCESS){
693
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
694
safer_gnutls_strerror(ret));
700
/* Use private key to suggest an appropriate
702
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
703
gnutls_openpgp_privkey_deinit(privkey);
705
fprintf_plus(stderr, "This OpenPGP key implies using"
706
" a GnuTLS security parameter \"%s\".\n",
707
safe_string(gnutls_sec_param_get_name
713
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
714
/* Err on the side of caution */
715
sec_param = GNUTLS_SEC_PARAM_ULTRA;
717
fprintf_plus(stderr, "Falling back to security parameter"
719
safe_string(gnutls_sec_param_get_name
724
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
728
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
729
" implies %u DH bits; using that.\n",
730
safe_string(gnutls_sec_param_get_name
735
fprintf_plus(stderr, "Failed to get implied number of DH"
736
" bits for security parameter \"%s\"): %s\n",
737
safe_string(gnutls_sec_param_get_name
739
safer_gnutls_strerror(ret));
743
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
746
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
747
if(ret != GNUTLS_E_SUCCESS){
748
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
749
" bits): %s\n", mc->dh_bits,
750
safer_gnutls_strerror(ret));
754
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
454
ret = gnutls_dh_params_init(&mc.dh_params);
455
if(ret != GNUTLS_E_SUCCESS){
456
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
457
" %s\n", safer_gnutls_strerror(ret));
460
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
461
if(ret != GNUTLS_E_SUCCESS){
462
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
463
safer_gnutls_strerror(ret));
467
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
760
gnutls_certificate_free_credentials(mc->cred);
761
gnutls_dh_params_deinit(mc->dh_params);
473
gnutls_certificate_free_credentials(mc.cred);
474
gnutls_global_deinit();
475
gnutls_dh_params_deinit(mc.dh_params);
765
__attribute__((nonnull, warn_unused_result))
766
static int init_gnutls_session(gnutls_session_t *session,
479
static int init_gnutls_session(gnutls_session_t *session){
769
481
/* GnuTLS session creation */
822
535
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
823
536
__attribute__((unused)) const char *txt){}
825
/* Set effective uid to 0, return errno */
826
__attribute__((warn_unused_result))
827
int raise_privileges(void){
828
int old_errno = errno;
830
if(seteuid(0) == -1){
837
/* Set effective and real user ID to 0. Return errno. */
838
__attribute__((warn_unused_result))
839
int raise_privileges_permanently(void){
840
int old_errno = errno;
841
int ret = raise_privileges();
853
/* Set effective user ID to unprivileged saved user ID */
854
__attribute__((warn_unused_result))
855
int lower_privileges(void){
856
int old_errno = errno;
858
if(seteuid(uid) == -1){
865
/* Lower privileges permanently */
866
__attribute__((warn_unused_result))
867
int lower_privileges_permanently(void){
868
int old_errno = errno;
870
if(setuid(uid) == -1){
877
/* Helper function to add_local_route() and delete_local_route() */
878
__attribute__((nonnull, warn_unused_result))
879
static bool add_delete_local_route(const bool add,
881
AvahiIfIndex if_index){
883
char helper[] = "mandos-client-iprouteadddel";
884
char add_arg[] = "add";
885
char delete_arg[] = "delete";
886
char debug_flag[] = "--debug";
887
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
888
if(pluginhelperdir == NULL){
890
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
891
" variable not set; cannot run helper\n");
896
char interface[IF_NAMESIZE];
897
if(if_indextoname((unsigned int)if_index, interface) == NULL){
898
perror_plus("if_indextoname");
902
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
904
perror_plus("open(\"/dev/null\", O_RDONLY)");
910
/* Raise privileges */
911
errno = raise_privileges_permanently();
913
perror_plus("Failed to raise privileges");
914
/* _exit(EX_NOPERM); */
920
perror_plus("setgid");
923
/* Reset supplementary groups */
925
ret = setgroups(0, NULL);
927
perror_plus("setgroups");
931
ret = dup2(devnull, STDIN_FILENO);
933
perror_plus("dup2(devnull, STDIN_FILENO)");
936
ret = close(devnull);
938
perror_plus("close");
941
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
943
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
946
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
951
if(helperdir_fd == -1){
953
_exit(EX_UNAVAILABLE);
955
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
958
perror_plus("openat");
960
_exit(EX_UNAVAILABLE);
964
#pragma GCC diagnostic push
965
#pragma GCC diagnostic ignored "-Wcast-qual"
967
if(fexecve(helper_fd, (char *const [])
968
{ helper, add ? add_arg : delete_arg, (char *)address,
969
interface, debug ? debug_flag : NULL, NULL },
972
#pragma GCC diagnostic pop
974
perror_plus("fexecve");
986
pret = waitpid(pid, &status, 0);
987
if(pret == -1 and errno == EINTR and quit_now){
988
int errno_raising = 0;
989
if((errno = raise_privileges()) != 0){
990
errno_raising = errno;
991
perror_plus("Failed to raise privileges in order to"
992
" kill helper program");
994
if(kill(pid, SIGTERM) == -1){
997
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
998
perror_plus("Failed to lower privileges after killing"
1003
} while(pret == -1 and errno == EINTR);
1005
perror_plus("waitpid");
1008
if(WIFEXITED(status)){
1009
if(WEXITSTATUS(status) != 0){
1010
fprintf_plus(stderr, "Error: iprouteadddel exited"
1011
" with status %d\n", WEXITSTATUS(status));
1016
if(WIFSIGNALED(status)){
1017
fprintf_plus(stderr, "Error: iprouteadddel died by"
1018
" signal %d\n", WTERMSIG(status));
1021
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1025
__attribute__((nonnull, warn_unused_result))
1026
static bool add_local_route(const char *address,
1027
AvahiIfIndex if_index){
1029
fprintf_plus(stderr, "Adding route to %s\n", address);
1031
return add_delete_local_route(true, address, if_index);
1034
__attribute__((nonnull, warn_unused_result))
1035
static bool delete_local_route(const char *address,
1036
AvahiIfIndex if_index){
1038
fprintf_plus(stderr, "Removing route to %s\n", address);
1040
return add_delete_local_route(false, address, if_index);
1043
538
/* Called when a Mandos server is found */
1044
__attribute__((nonnull, warn_unused_result))
1045
static int start_mandos_communication(const char *ip, in_port_t port,
539
static int start_mandos_communication(const char *ip, uint16_t port,
1046
540
AvahiIfIndex if_index,
1047
int af, mandos_context *mc){
1048
542
int ret, tcp_sd = -1;
1050
struct sockaddr_storage to;
545
struct sockaddr_in in;
546
struct sockaddr_in6 in6;
1051
548
char *buffer = NULL;
1052
549
char *decrypted_buffer = NULL;
1053
550
size_t buffer_length = 0;
1076
fprintf_plus(stderr, "Bad address family: %d\n", af);
569
fprintf(stderr, "Bad address family: %d\n", af);
1081
/* If the interface is specified and we have a list of interfaces */
1082
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1083
/* Check if the interface is one of the interfaces we are using */
1086
char *interface = NULL;
1087
while((interface = argz_next(mc->interfaces,
1088
mc->interfaces_size,
1090
if(if_nametoindex(interface) == (unsigned int)if_index){
1097
/* This interface does not match any in the list, so we don't
1098
connect to the server */
1100
char interface[IF_NAMESIZE];
1101
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1102
perror_plus("if_indextoname");
1104
fprintf_plus(stderr, "Skipping server on non-used interface"
1106
if_indextoname((unsigned int)if_index,
1114
ret = init_gnutls_session(&session, mc);
573
ret = init_gnutls_session(&session);
1120
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1121
PRIuMAX "\n", ip, (uintmax_t)port);
579
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1124
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
583
tcp_sd = socket(pf, SOCK_STREAM, 0);
1127
perror_plus("socket");
1129
586
goto mandos_end;
1134
590
goto mandos_end;
593
memset(&to, 0, sizeof(to));
1137
594
if(af == AF_INET6){
1138
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1139
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1140
ret = inet_pton(af, ip, &to6->sin6_addr);
595
to.in6.sin6_family = (sa_family_t)af;
596
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1141
597
} else { /* IPv4 */
1142
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1143
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1144
ret = inet_pton(af, ip, &to4->sin_addr);
598
to.in.sin_family = (sa_family_t)af;
599
ret = inet_pton(af, ip, &to.in.sin_addr);
1148
perror_plus("inet_pton");
1150
603
goto mandos_end;
1154
fprintf_plus(stderr, "Bad address: %s\n", ip);
606
fprintf(stderr, "Bad address: %s\n", ip);
1156
607
goto mandos_end;
1158
609
if(af == AF_INET6){
1159
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1160
if(IN6_IS_ADDR_LINKLOCAL
1161
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
610
to.in6.sin6_port = htons(port); /* Spurious warnings from
612
-Wunreachable-code */
614
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
615
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
1162
617
if(if_index == AVAHI_IF_UNSPEC){
1163
fprintf_plus(stderr, "An IPv6 link-local address is"
1164
" incomplete without a network interface\n");
618
fprintf(stderr, "An IPv6 link-local address is incomplete"
619
" without a network interface\n");
1166
620
goto mandos_end;
1168
622
/* Set the network interface number as scope */
1169
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
623
to.in6.sin6_scope_id = (uint32_t)if_index;
1172
((struct sockaddr_in *)&to)->sin_port = htons(port);
626
to.in.sin_port = htons(port); /* Spurious warnings from
628
-Wunreachable-code */
1177
632
goto mandos_end;
1181
636
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1182
637
char interface[IF_NAMESIZE];
1183
638
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1184
perror_plus("if_indextoname");
639
perror("if_indextoname");
1186
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1187
"\n", ip, interface, (uintmax_t)port);
641
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
642
ip, interface, port);
1190
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1191
ip, (uintmax_t)port);
645
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1193
648
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1194
649
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1196
ret = getnameinfo((struct sockaddr *)&to,
1197
sizeof(struct sockaddr_in6),
1198
addrstr, sizeof(addrstr), NULL, 0,
1201
ret = getnameinfo((struct sockaddr *)&to,
1202
sizeof(struct sockaddr_in),
1203
addrstr, sizeof(addrstr), NULL, 0,
1206
if(ret == EAI_SYSTEM){
1207
perror_plus("getnameinfo");
1208
} else if(ret != 0) {
1209
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1210
} else if(strcmp(addrstr, ip) != 0){
1211
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1222
ret = connect(tcp_sd, (struct sockaddr *)&to,
1223
sizeof(struct sockaddr_in6));
1225
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1226
sizeof(struct sockaddr_in));
1229
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1230
and if_index != AVAHI_IF_UNSPEC
1231
and connect_to == NULL
1232
and not route_added and
1233
((af == AF_INET6 and not
1234
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1236
or (af == AF_INET and
1237
/* Not a a IPv4LL address */
1238
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1239
& 0xFFFF0000L) != 0xA9FE0000L))){
1240
/* Work around Avahi bug - Avahi does not announce link-local
1241
addresses if it has a global address, so local hosts with
1242
*only* a link-local address (e.g. Mandos clients) cannot
1243
connect to a Mandos server announced by Avahi on a server
1244
host with a global address. Work around this by retrying
1245
with an explicit route added with the server's address.
1247
Avahi bug reference:
1248
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1249
https://bugs.debian.org/587961
1252
fprintf_plus(stderr, "Mandos server unreachable, trying"
1256
route_added = add_local_route(ip, if_index);
1262
if(errno != ECONNREFUSED or debug){
1264
perror_plus("connect");
652
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
655
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
661
if(strcmp(addrstr, ip) != 0){
662
fprintf(stderr, "Canonical address form: %s\n", addrstr);
672
ret = connect(tcp_sd, &to.in6, sizeof(to));
674
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
1277
685
const char *out = mandos_protocol_version;
1632
971
signal_received = sig;
1633
972
int old_errno = errno;
1634
/* set main loop to exit */
1635
if(simple_poll != NULL){
1636
avahi_simple_poll_quit(simple_poll);
973
if(mc.simple_poll != NULL){
974
avahi_simple_poll_quit(mc.simple_poll);
1638
976
errno = old_errno;
1641
__attribute__((nonnull, warn_unused_result))
1642
bool get_flags(const char *ifname, struct ifreq *ifr){
1646
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1649
perror_plus("socket");
1653
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1654
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1655
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1659
perror_plus("ioctl SIOCGIFFLAGS");
1662
if((close(s) == -1) and debug){
1664
perror_plus("close");
1669
if((close(s) == -1) and debug){
1671
perror_plus("close");
1677
__attribute__((nonnull, warn_unused_result))
1678
bool good_flags(const char *ifname, const struct ifreq *ifr){
1680
/* Reject the loopback device */
1681
if(ifr->ifr_flags & IFF_LOOPBACK){
1683
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1688
/* Accept point-to-point devices only if connect_to is specified */
1689
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1691
fprintf_plus(stderr, "Accepting point-to-point interface"
1692
" \"%s\"\n", ifname);
1696
/* Otherwise, reject non-broadcast-capable devices */
1697
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1699
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1700
" \"%s\"\n", ifname);
1704
/* Reject non-ARP interfaces (including dummy interfaces) */
1705
if(ifr->ifr_flags & IFF_NOARP){
1707
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1713
/* Accept this device */
1715
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1721
980
* This function determines if a directory entry in /sys/class/net
1722
981
* corresponds to an acceptable network device.
1723
982
* (This function is passed to scandir(3) as a filter function.)
1725
__attribute__((nonnull, warn_unused_result))
1726
984
int good_interface(const struct dirent *if_entry){
986
char *flagname = NULL;
987
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1727
993
if(if_entry->d_name[0] == '.'){
1732
if(not get_flags(if_entry->d_name, &ifr)){
1734
fprintf_plus(stderr, "Failed to get flags for interface "
1735
"\"%s\"\n", if_entry->d_name);
1740
if(not good_flags(if_entry->d_name, &ifr)){
1747
* This function determines if a network interface is up.
1749
__attribute__((nonnull, warn_unused_result))
1750
bool interface_is_up(const char *interface){
1752
if(not get_flags(interface, &ifr)){
1754
fprintf_plus(stderr, "Failed to get flags for interface "
1755
"\"%s\"\n", interface);
1760
return (bool)(ifr.ifr_flags & IFF_UP);
1764
* This function determines if a network interface is running
1766
__attribute__((nonnull, warn_unused_result))
1767
bool interface_is_running(const char *interface){
1769
if(not get_flags(interface, &ifr)){
1771
fprintf_plus(stderr, "Failed to get flags for interface "
1772
"\"%s\"\n", interface);
1777
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1780
__attribute__((nonnull, pure, warn_unused_result))
1781
int notdotentries(const struct dirent *direntry){
1782
/* Skip "." and ".." */
1783
if(direntry->d_name[0] == '.'
1784
and (direntry->d_name[1] == '\0'
1785
or (direntry->d_name[1] == '.'
1786
and direntry->d_name[2] == '\0'))){
1792
/* Is this directory entry a runnable program? */
1793
__attribute__((nonnull, warn_unused_result))
1794
int runnable_hook(const struct dirent *direntry){
1799
if((direntry->d_name)[0] == '\0'){
1804
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1805
"abcdefghijklmnopqrstuvwxyz"
1808
if((direntry->d_name)[sret] != '\0'){
1809
/* Contains non-allowed characters */
1811
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1817
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1820
perror_plus("Could not stat hook");
1824
if(not (S_ISREG(st.st_mode))){
1825
/* Not a regular file */
1827
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1832
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1833
/* Not executable */
1835
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1841
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1847
__attribute__((nonnull, warn_unused_result))
1848
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1849
mandos_context *mc){
1851
struct timespec now;
1852
struct timespec waited_time;
1853
intmax_t block_time;
1856
if(mc->current_server == NULL){
1858
fprintf_plus(stderr, "Wait until first server is found."
1861
ret = avahi_simple_poll_iterate(s, -1);
1864
fprintf_plus(stderr, "Check current_server if we should run"
1867
/* the current time */
1868
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1870
perror_plus("clock_gettime");
1873
/* Calculating in ms how long time between now and server
1874
who we visted longest time ago. Now - last seen. */
1875
waited_time.tv_sec = (now.tv_sec
1876
- mc->current_server->last_seen.tv_sec);
1877
waited_time.tv_nsec = (now.tv_nsec
1878
- mc->current_server->last_seen.tv_nsec);
1879
/* total time is 10s/10,000ms.
1880
Converting to s from ms by dividing by 1,000,
1881
and ns to ms by dividing by 1,000,000. */
1882
block_time = ((retry_interval
1883
- ((intmax_t)waited_time.tv_sec * 1000))
1884
- ((intmax_t)waited_time.tv_nsec / 1000000));
1887
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1891
if(block_time <= 0){
1892
ret = start_mandos_communication(mc->current_server->ip,
1893
mc->current_server->port,
1894
mc->current_server->if_index,
1895
mc->current_server->af, mc);
1897
avahi_simple_poll_quit(s);
1900
ret = clock_gettime(CLOCK_MONOTONIC,
1901
&mc->current_server->last_seen);
1903
perror_plus("clock_gettime");
1906
mc->current_server = mc->current_server->next;
1907
block_time = 0; /* Call avahi to find new Mandos
1908
servers, but don't block */
1911
ret = avahi_simple_poll_iterate(s, (int)block_time);
1914
if(ret > 0 or errno != EINTR){
1915
return (ret != 1) ? ret : 0;
1921
__attribute__((nonnull))
1922
void run_network_hooks(const char *mode, const char *interface,
1924
struct dirent **direntries = NULL;
1925
if(hookdir_fd == -1){
1926
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1928
if(hookdir_fd == -1){
1929
if(errno == ENOENT){
1931
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1932
" found\n", hookdir);
1935
perror_plus("open");
1940
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1942
perror_plus("open(\"/dev/null\", O_RDONLY)");
1945
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1946
runnable_hook, alphasort);
1948
perror_plus("scandir");
1952
struct dirent *direntry;
1954
for(int i = 0; i < numhooks; i++){
1955
direntry = direntries[i];
1957
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1960
pid_t hook_pid = fork();
1963
/* Raise privileges */
1964
errno = raise_privileges_permanently();
1966
perror_plus("Failed to raise privileges");
1973
perror_plus("setgid");
1976
/* Reset supplementary groups */
1978
ret = setgroups(0, NULL);
1980
perror_plus("setgroups");
1983
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1985
perror_plus("setenv");
1988
ret = setenv("DEVICE", interface, 1);
1990
perror_plus("setenv");
1993
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1995
perror_plus("setenv");
1998
ret = setenv("MODE", mode, 1);
2000
perror_plus("setenv");
2004
ret = asprintf(&delaystring, "%f", (double)delay);
2006
perror_plus("asprintf");
2009
ret = setenv("DELAY", delaystring, 1);
2012
perror_plus("setenv");
2016
if(connect_to != NULL){
2017
ret = setenv("CONNECT", connect_to, 1);
2019
perror_plus("setenv");
2023
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2027
perror_plus("openat");
2028
_exit(EXIT_FAILURE);
2030
if(close(hookdir_fd) == -1){
2031
perror_plus("close");
2032
_exit(EXIT_FAILURE);
2034
ret = dup2(devnull, STDIN_FILENO);
2036
perror_plus("dup2(devnull, STDIN_FILENO)");
2039
ret = close(devnull);
2041
perror_plus("close");
2044
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2046
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2049
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2051
perror_plus("fexecve");
2052
_exit(EXIT_FAILURE);
2056
perror_plus("fork");
2061
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2062
perror_plus("waitpid");
2066
if(WIFEXITED(status)){
2067
if(WEXITSTATUS(status) != 0){
2068
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2069
" with status %d\n", direntry->d_name,
2070
WEXITSTATUS(status));
2074
} else if(WIFSIGNALED(status)){
2075
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2076
" signal %d\n", direntry->d_name,
2081
fprintf_plus(stderr, "Warning: network hook \"%s\""
2082
" crashed\n", direntry->d_name);
2088
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2094
if(close(hookdir_fd) == -1){
2095
perror_plus("close");
2102
__attribute__((nonnull, warn_unused_result))
2103
int bring_up_interface(const char *const interface,
2105
int old_errno = errno;
2107
struct ifreq network;
2108
unsigned int if_index = if_nametoindex(interface);
2110
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2120
if(not interface_is_up(interface)){
2122
int ioctl_errno = 0;
2123
if(not get_flags(interface, &network)){
2125
fprintf_plus(stderr, "Failed to get flags for interface "
2126
"\"%s\"\n", interface);
2130
network.ifr_flags |= IFF_UP; /* set flag */
2132
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2135
perror_plus("socket");
2143
perror_plus("close");
2150
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2154
/* Raise privileges */
2155
ret_errno = raise_privileges();
2158
perror_plus("Failed to raise privileges");
2163
bool restore_loglevel = false;
2165
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2166
messages about the network interface to mess up the prompt */
2167
ret_linux = klogctl(8, NULL, 5);
2168
if(ret_linux == -1){
2169
perror_plus("klogctl");
2171
restore_loglevel = true;
2174
#endif /* __linux__ */
2175
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2176
ioctl_errno = errno;
2178
if(restore_loglevel){
2179
ret_linux = klogctl(7, NULL, 0);
2180
if(ret_linux == -1){
2181
perror_plus("klogctl");
2184
#endif /* __linux__ */
2186
/* If raise_privileges() succeeded above */
2188
/* Lower privileges */
2189
ret_errno = lower_privileges();
2192
perror_plus("Failed to lower privileges");
2196
/* Close the socket */
2199
perror_plus("close");
2202
if(ret_setflags == -1){
2203
errno = ioctl_errno;
2204
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2209
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2213
/* Sleep checking until interface is running.
2214
Check every 0.25s, up to total time of delay */
2215
for(int i = 0; i < delay * 4; i++){
2216
if(interface_is_running(interface)){
996
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1001
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1002
/* read line from flags_fd */
1003
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1004
char *flagstring = malloc((size_t)to_read);
1005
if(flagstring == NULL){
1011
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
2219
struct timespec sleeptime = { .tv_nsec = 250000000 };
2220
ret = nanosleep(&sleeptime, NULL);
2221
if(ret == -1 and errno != EINTR){
2222
perror_plus("nanosleep");
2230
__attribute__((nonnull, warn_unused_result))
2231
int take_down_interface(const char *const interface){
2232
int old_errno = errno;
2233
struct ifreq network;
2234
unsigned int if_index = if_nametoindex(interface);
2236
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2240
if(interface_is_up(interface)){
2242
int ioctl_errno = 0;
2243
if(not get_flags(interface, &network) and debug){
2245
fprintf_plus(stderr, "Failed to get flags for interface "
2246
"\"%s\"\n", interface);
2250
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2252
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2255
perror_plus("socket");
2261
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2265
/* Raise privileges */
2266
ret_errno = raise_privileges();
2269
perror_plus("Failed to raise privileges");
2272
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2273
ioctl_errno = errno;
2275
/* If raise_privileges() succeeded above */
2277
/* Lower privileges */
2278
ret_errno = lower_privileges();
2281
perror_plus("Failed to lower privileges");
2285
/* Close the socket */
2286
int ret = close(sd);
2288
perror_plus("close");
2291
if(ret_setflags == -1){
2292
errno = ioctl_errno;
2293
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2298
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1028
tmpmax = strtoimax(flagstring, &tmp, 0);
1029
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1030
and not (isspace(*tmp)))
1031
or tmpmax != (ifreq_flags)tmpmax){
1036
ifreq_flags flags = (ifreq_flags)tmpmax;
1037
/* Reject the loopback device */
1038
if(flags & IFF_LOOPBACK){
1041
/* Accept point-to-point devices only if connect_to is specified */
1042
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1045
/* Otherwise, reject non-broadcast-capable devices */
1046
if(not (flags & IFF_BROADCAST)){
1049
/* Accept this device */
2306
1053
int main(int argc, char *argv[]){
2307
mandos_context mc = { .server = NULL, .dh_bits = 0,
2308
.priority = "SECURE256:!CTYPE-X.509"
2309
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2310
.current_server = NULL, .interfaces = NULL,
2311
.interfaces_size = 0 };
2312
1054
AvahiSServiceBrowser *sb = NULL;
2315
1057
intmax_t tmpmax;
2317
1059
int exitcode = EXIT_SUCCESS;
2318
char *interfaces_to_take_down = NULL;
2319
size_t interfaces_to_take_down_size = 0;
2320
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2321
char old_tempdir[] = "/tmp/mandosXXXXXX";
2322
char *tempdir = NULL;
1060
const char *interface = "";
1061
struct ifreq network;
1063
bool take_down_interface = false;
1066
char tempdir[] = "/tmp/mandosXXXXXX";
1067
bool tempdir_created = false;
2323
1068
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2324
1069
const char *seckey = PATHDIR "/" SECKEY;
2325
1070
const char *pubkey = PATHDIR "/" PUBKEY;
2326
const char *dh_params_file = NULL;
2327
char *interfaces_hooks = NULL;
2329
1072
bool gnutls_initialized = false;
2330
1073
bool gpgme_initialized = false;
2331
1074
float delay = 2.5f;
2332
double retry_interval = 10; /* 10s between trying a server and
2333
retrying the same server again */
2335
1076
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2336
1077
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2458
1170
delay = strtof(arg, &tmp);
2459
1171
if(errno != 0 or tmp == arg or *tmp != '\0'){
2460
argp_error(state, "Bad delay");
2462
case 132: /* --retry */
2464
retry_interval = strtod(arg, &tmp);
2465
if(errno != 0 or tmp == arg or *tmp != '\0'
2466
or (retry_interval * 1000) > INT_MAX
2467
or retry_interval < 0){
2468
argp_error(state, "Bad retry interval");
2471
case 133: /* --network-hook-dir */
2475
* These reproduce what we would get without ARGP_NO_HELP
2477
case '?': /* --help */
2478
argp_state_help(state, state->out_stream,
2479
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2480
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2481
case -3: /* --usage */
2482
argp_state_help(state, state->out_stream,
2483
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2484
case 'V': /* --version */
2485
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2486
exit(argp_err_exit_status);
1172
fprintf(stderr, "Bad delay\n");
2489
1181
return ARGP_ERR_UNKNOWN;
2494
1186
struct argp argp = { .options = options, .parser = parse_opt,
2495
1187
.args_doc = "",
2496
1188
.doc = "Mandos client -- Get and decrypt"
2497
1189
" passwords from a Mandos server" };
2498
ret_errno = argp_parse(&argp, argc, argv,
2499
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2506
perror_plus("argp_parse");
2507
exitcode = EX_OSERR;
2510
exitcode = EX_USAGE;
2516
/* Work around Debian bug #633582:
2517
<https://bugs.debian.org/633582> */
2519
/* Re-raise privileges */
2520
ret = raise_privileges();
2523
perror_plus("Failed to raise privileges");
2527
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2528
int seckey_fd = open(seckey, O_RDONLY);
2529
if(seckey_fd == -1){
2530
perror_plus("open");
2532
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2534
perror_plus("fstat");
2536
if(S_ISREG(st.st_mode)
2537
and st.st_uid == 0 and st.st_gid == 0){
2538
ret = fchown(seckey_fd, uid, gid);
2540
perror_plus("fchown");
2548
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2549
int pubkey_fd = open(pubkey, O_RDONLY);
2550
if(pubkey_fd == -1){
2551
perror_plus("open");
2553
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2555
perror_plus("fstat");
2557
if(S_ISREG(st.st_mode)
2558
and st.st_uid == 0 and st.st_gid == 0){
2559
ret = fchown(pubkey_fd, uid, gid);
2561
perror_plus("fchown");
2569
if(dh_params_file != NULL
2570
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2571
int dhparams_fd = open(dh_params_file, O_RDONLY);
2572
if(dhparams_fd == -1){
2573
perror_plus("open");
2575
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2577
perror_plus("fstat");
2579
if(S_ISREG(st.st_mode)
2580
and st.st_uid == 0 and st.st_gid == 0){
2581
ret = fchown(dhparams_fd, uid, gid);
2583
perror_plus("fchown");
2591
/* Lower privileges */
2592
ret = lower_privileges();
2595
perror_plus("Failed to lower privileges");
2600
/* Remove invalid interface names (except "none") */
2602
char *interface = NULL;
2603
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2605
if(strcmp(interface, "none") != 0
2606
and if_nametoindex(interface) == 0){
2607
if(interface[0] != '\0'){
2608
fprintf_plus(stderr, "Not using nonexisting interface"
2609
" \"%s\"\n", interface);
2611
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2617
/* Run network hooks */
2619
if(mc.interfaces != NULL){
2620
interfaces_hooks = malloc(mc.interfaces_size);
2621
if(interfaces_hooks == NULL){
2622
perror_plus("malloc");
2625
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2626
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2628
run_network_hooks("start", interfaces_hooks != NULL ?
2629
interfaces_hooks : "", delay);
1190
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1191
if(ret == ARGP_ERR_UNKNOWN){
1192
fprintf(stderr, "Unknown error while parsing arguments\n");
1193
exitcode = EXIT_FAILURE;
2633
1199
avahi_set_log_function(empty_log);
1202
if(interface[0] == '\0'){
1203
struct dirent **direntries;
1204
ret = scandir(sys_class_net, &direntries, good_interface,
1207
/* Pick the first good interface */
1208
interface = strdup(direntries[0]->d_name);
1209
if(interface == NULL){
1212
exitcode = EXIT_FAILURE;
1218
fprintf(stderr, "Could not find a network interface\n");
1219
exitcode = EXIT_FAILURE;
2636
1224
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2637
1225
from the signal handler */
2638
1226
/* Initialize the pseudo-RNG for Avahi */
2639
1227
srand((unsigned int) time(NULL));
2640
simple_poll = avahi_simple_poll_new();
2641
if(simple_poll == NULL){
2642
fprintf_plus(stderr,
2643
"Avahi: Failed to create simple poll object.\n");
2644
exitcode = EX_UNAVAILABLE;
1228
mc.simple_poll = avahi_simple_poll_new();
1229
if(mc.simple_poll == NULL){
1230
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1231
exitcode = EXIT_FAILURE;
2648
1235
sigemptyset(&sigterm_action.sa_mask);
2649
1236
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2651
perror_plus("sigaddset");
2652
exitcode = EX_OSERR;
1238
perror("sigaddset");
1239
exitcode = EXIT_FAILURE;
2655
1242
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2657
perror_plus("sigaddset");
2658
exitcode = EX_OSERR;
1244
perror("sigaddset");
1245
exitcode = EXIT_FAILURE;
2661
1248
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2663
perror_plus("sigaddset");
2664
exitcode = EX_OSERR;
1250
perror("sigaddset");
1251
exitcode = EXIT_FAILURE;
2667
1254
/* Need to check if the handler is SIG_IGN before handling:
2671
1258
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2673
perror_plus("sigaction");
1260
perror("sigaction");
1261
return EXIT_FAILURE;
2676
1263
if(old_sigterm_action.sa_handler != SIG_IGN){
2677
1264
ret = sigaction(SIGINT, &sigterm_action, NULL);
2679
perror_plus("sigaction");
2680
exitcode = EX_OSERR;
1266
perror("sigaction");
1267
exitcode = EXIT_FAILURE;
2684
1271
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2686
perror_plus("sigaction");
1273
perror("sigaction");
1274
return EXIT_FAILURE;
2689
1276
if(old_sigterm_action.sa_handler != SIG_IGN){
2690
1277
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2692
perror_plus("sigaction");
2693
exitcode = EX_OSERR;
1279
perror("sigaction");
1280
exitcode = EXIT_FAILURE;
2697
1284
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2699
perror_plus("sigaction");
1286
perror("sigaction");
1287
return EXIT_FAILURE;
2702
1289
if(old_sigterm_action.sa_handler != SIG_IGN){
2703
1290
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2705
perror_plus("sigaction");
2706
exitcode = EX_OSERR;
1292
perror("sigaction");
1293
exitcode = EXIT_FAILURE;
2711
/* If no interfaces were specified, make a list */
2712
if(mc.interfaces == NULL){
2713
struct dirent **direntries = NULL;
2714
/* Look for any good interfaces */
2715
ret = scandir(sys_class_net, &direntries, good_interface,
2718
/* Add all found interfaces to interfaces list */
2719
for(int i = 0; i < ret; ++i){
2720
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2721
direntries[i]->d_name);
2724
perror_plus("argz_add");
2725
free(direntries[i]);
2729
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2730
direntries[i]->d_name);
2732
free(direntries[i]);
1298
/* If the interface is down, bring it up */
1299
if(strcmp(interface, "none") != 0){
1300
if_index = (AvahiIfIndex) if_nametoindex(interface);
1302
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1303
exitcode = EXIT_FAILURE;
1311
/* Re-raise priviliges */
1319
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1320
messages to mess up the prompt */
1321
ret = klogctl(8, NULL, 5);
1322
bool restore_loglevel = true;
1324
restore_loglevel = false;
1327
#endif /* __linux__ */
1329
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1332
exitcode = EXIT_FAILURE;
1334
if(restore_loglevel){
1335
ret = klogctl(7, NULL, 0);
1340
#endif /* __linux__ */
1341
/* Lower privileges */
1349
strcpy(network.ifr_name, interface);
1350
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1352
perror("ioctl SIOCGIFFLAGS");
1354
if(restore_loglevel){
1355
ret = klogctl(7, NULL, 0);
1360
#endif /* __linux__ */
1361
exitcode = EXIT_FAILURE;
1362
/* Lower privileges */
1370
if((network.ifr_flags & IFF_UP) == 0){
1371
network.ifr_flags |= IFF_UP;
1372
take_down_interface = true;
1373
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1375
take_down_interface = false;
1376
perror("ioctl SIOCSIFFLAGS");
1377
exitcode = EXIT_FAILURE;
1379
if(restore_loglevel){
1380
ret = klogctl(7, NULL, 0);
1385
#endif /* __linux__ */
1386
/* Lower privileges */
1395
/* sleep checking until interface is running */
1396
for(int i=0; i < delay * 4; i++){
1397
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1399
perror("ioctl SIOCGIFFLAGS");
1400
} else if(network.ifr_flags & IFF_RUNNING){
1403
struct timespec sleeptime = { .tv_nsec = 250000000 };
1404
ret = nanosleep(&sleeptime, NULL);
1405
if(ret == -1 and errno != EINTR){
1406
perror("nanosleep");
1409
if(not take_down_interface){
1410
/* We won't need the socket anymore */
1411
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1417
if(restore_loglevel){
1418
/* Restores kernel loglevel to default */
1419
ret = klogctl(7, NULL, 0);
1424
#endif /* __linux__ */
1425
/* Lower privileges */
1427
if(take_down_interface){
1428
/* Lower privileges */
2739
fprintf_plus(stderr, "Could not find a network interface\n");
2740
exitcode = EXIT_FAILURE;
2745
/* Bring up interfaces which are down, and remove any "none"s */
2747
char *interface = NULL;
2748
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2750
/* If interface name is "none", stop bringing up interfaces.
2751
Also remove all instances of "none" from the list */
2752
if(strcmp(interface, "none") == 0){
2753
argz_delete(&mc.interfaces, &mc.interfaces_size,
2756
while((interface = argz_next(mc.interfaces,
2757
mc.interfaces_size, interface))){
2758
if(strcmp(interface, "none") == 0){
2759
argz_delete(&mc.interfaces, &mc.interfaces_size,
2766
bool interface_was_up = interface_is_up(interface);
2767
errno = bring_up_interface(interface, delay);
2768
if(not interface_was_up){
2770
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2771
" %s\n", interface, strerror(errno));
2773
errno = argz_add(&interfaces_to_take_down,
2774
&interfaces_to_take_down_size,
2777
perror_plus("argz_add");
2782
if(debug and (interfaces_to_take_down == NULL)){
2783
fprintf_plus(stderr, "No interfaces were brought up\n");
2787
/* If we only got one interface, explicitly use only that one */
2788
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2790
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2793
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1434
/* Lower privileges permanently */
2800
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1446
ret = init_gnutls_global(pubkey, seckey);
2802
fprintf_plus(stderr, "init_gnutls_global failed\n");
2803
exitcode = EX_UNAVAILABLE;
1448
fprintf(stderr, "init_gnutls_global failed\n");
1449
exitcode = EXIT_FAILURE;
2806
1452
gnutls_initialized = true;
3005
1614
gpgme_release(mc.ctx);
3008
/* Cleans up the circular linked list of Mandos servers the client
3010
if(mc.current_server != NULL){
3011
mc.current_server->prev->next = NULL;
3012
while(mc.current_server != NULL){
3013
server *next = mc.current_server->next;
3015
#pragma GCC diagnostic push
3016
#pragma GCC diagnostic ignored "-Wcast-qual"
3018
free((char *)(mc.current_server->ip));
3020
#pragma GCC diagnostic pop
3022
free(mc.current_server);
3023
mc.current_server = next;
3027
/* Re-raise privileges */
3029
ret = raise_privileges();
3032
perror_plus("Failed to raise privileges");
3035
/* Run network hooks */
3036
run_network_hooks("stop", interfaces_hooks != NULL ?
3037
interfaces_hooks : "", delay);
3039
/* Take down the network interfaces which were brought up */
3041
char *interface = NULL;
3042
while((interface = argz_next(interfaces_to_take_down,
3043
interfaces_to_take_down_size,
3045
ret = take_down_interface(interface);
3048
perror_plus("Failed to take down interface");
3051
if(debug and (interfaces_to_take_down == NULL)){
3052
fprintf_plus(stderr, "No interfaces needed to be taken"
3058
ret = lower_privileges_permanently();
3061
perror_plus("Failed to lower privileges permanently");
3065
free(interfaces_to_take_down);
3066
free(interfaces_hooks);
3068
void clean_dir_at(int base, const char * const dirname,
3070
struct dirent **direntries = NULL;
3072
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3078
perror_plus("open");
3081
int numentries = scandirat(dir_fd, ".", &direntries,
3082
notdotentries, alphasort);
3083
if(numentries >= 0){
3084
for(int i = 0; i < numentries; i++){
3086
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3087
dirname, direntries[i]->d_name);
3089
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3091
if(errno == EISDIR){
3092
dret = unlinkat(dir_fd, direntries[i]->d_name,
3095
if((dret == -1) and (errno == ENOTEMPTY)
3096
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3097
== 0) and (level == 0)){
3098
/* Recurse only in this special case */
3099
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3102
if((dret == -1) and (errno != ENOENT)){
3103
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3104
direntries[i]->d_name, strerror(errno));
3107
free(direntries[i]);
3110
/* need to clean even if 0 because man page doesn't specify */
3112
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3113
if(dret == -1 and errno != ENOENT){
3114
perror_plus("rmdir");
3117
perror_plus("scandirat");
3122
/* Removes the GPGME temp directory and all files inside */
3123
if(tempdir != NULL){
3124
clean_dir_at(-1, tempdir, 0);
1617
/* Take down the network interface */
1618
if(take_down_interface){
1619
/* Re-raise priviliges */
1626
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1628
perror("ioctl SIOCGIFFLAGS");
1629
} else if(network.ifr_flags & IFF_UP) {
1630
network.ifr_flags &= ~IFF_UP; /* clear flag */
1631
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1633
perror("ioctl SIOCSIFFLAGS");
1636
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1640
/* Lower privileges permanently */
1649
/* Removes the temp directory used by GPGME */
1650
if(tempdir_created){
1652
struct dirent *direntry;
1653
d = opendir(tempdir);
1655
if(errno != ENOENT){
1660
direntry = readdir(d);
1661
if(direntry == NULL){
1664
/* Skip "." and ".." */
1665
if(direntry->d_name[0] == '.'
1666
and (direntry->d_name[1] == '\0'
1667
or (direntry->d_name[1] == '.'
1668
and direntry->d_name[2] == '\0'))){
1671
char *fullname = NULL;
1672
ret = asprintf(&fullname, "%s/%s", tempdir,
1678
ret = remove(fullname);
1680
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1687
ret = rmdir(tempdir);
1688
if(ret == -1 and errno != ENOENT){