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));
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
316
perror_plus("close");
318
210
gpgme_data_release(pgp_data);
323
fprintf_plus(stderr, "Initializing GPGME\n");
215
fprintf(stderr, "Initializing GPGME\n");
327
219
gpgme_check_version(NULL);
328
220
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
329
221
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));
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
335
/* Set GPGME home directory for the OpenPGP engine only */
227
/* Set GPGME home directory for the OpenPGP engine only */
336
228
rc = gpgme_get_engine_info(&engine_info);
337
229
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));
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
342
234
while(engine_info != NULL){
385
273
ssize_t plaintext_length = 0;
388
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
391
279
/* Create new GPGME data buffer from memory cryptotext */
392
280
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
394
282
if(rc != GPG_ERR_NO_ERROR){
395
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
396
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));
400
288
/* Create new empty GPGME data buffer for the plaintext */
401
289
rc = gpgme_data_new(&dh_plain);
402
290
if(rc != GPG_ERR_NO_ERROR){
403
fprintf_plus(stderr, "Mandos plugin mandos-client: "
404
"bad gpgme_data_new: %s: %s\n",
405
gpgme_strsource(rc), gpgme_strerror(rc));
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
406
293
gpgme_data_release(dh_crypto);
410
297
/* Decrypt data from the cryptotext data buffer to the plaintext
412
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
413
300
if(rc != GPG_ERR_NO_ERROR){
414
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
415
gpgme_strsource(rc), gpgme_strerror(rc));
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
416
303
plaintext_length = -1;
418
305
gpgme_decrypt_result_t result;
419
result = gpgme_op_decrypt_result(mc->ctx);
306
result = gpgme_op_decrypt_result(mc.ctx);
420
307
if(result == NULL){
421
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
423
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
424
result->unsupported_algorithm);
425
fprintf_plus(stderr, "Wrong key usage: %u\n",
426
result->wrong_key_usage);
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
427
314
if(result->file_name != NULL){
428
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
fprintf(stderr, "File name: %s\n", result->file_name);
430
317
gpgme_recipient_t recipient;
431
318
recipient = result->recipients;
432
319
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
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
440
326
recipient = recipient->next;
542
425
/* OpenPGP credentials */
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
426
gnutls_certificate_allocate_credentials(&mc.cred);
544
427
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
546
safer_gnutls_strerror(ret));
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
432
safer_gnutls_strerror(ret));
433
gnutls_global_deinit();
551
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
552
" 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,
557
443
ret = gnutls_certificate_set_openpgp_key_file
558
(mc->cred, pubkeyfilename, seckeyfilename,
444
(mc.cred, pubkeyfilename, seckeyfilename,
559
445
GNUTLS_OPENPGP_FMT_BASE64);
560
446
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));
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));
569
455
/* 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;
617
if(params.data == NULL){
618
dhparamsfilename = NULL;
620
if(dhparamsfilename == NULL){
623
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
624
GNUTLS_X509_FMT_PEM);
625
if(ret != GNUTLS_E_SUCCESS){
626
fprintf_plus(stderr, "Failed to parse DH parameters in file"
627
" \"%s\": %s\n", dhparamsfilename,
628
safer_gnutls_strerror(ret));
629
dhparamsfilename = NULL;
634
if(dhparamsfilename == NULL){
635
if(mc->dh_bits == 0){
636
/* Find out the optimal number of DH bits */
637
/* Try to read the private key file */
638
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
640
int secfile = open(seckeyfilename, O_RDONLY);
645
size_t buffer_capacity = 0;
647
buffer_capacity = incbuffer((char **)&buffer.data,
649
(size_t)buffer_capacity);
650
if(buffer_capacity == 0){
651
perror_plus("incbuffer");
656
ssize_t bytes_read = read(secfile,
657
buffer.data + buffer.size,
663
/* check bytes_read for failure */
670
buffer.size += (unsigned int)bytes_read;
674
/* If successful, use buffer to parse private key */
675
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
676
if(buffer.data != NULL){
678
gnutls_openpgp_privkey_t privkey = NULL;
679
ret = gnutls_openpgp_privkey_init(&privkey);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error initializing OpenPGP key"
683
safer_gnutls_strerror(ret));
687
ret = gnutls_openpgp_privkey_import
688
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
689
if(ret != GNUTLS_E_SUCCESS){
690
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
691
safer_gnutls_strerror(ret));
697
/* Use private key to suggest an appropriate
699
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
700
gnutls_openpgp_privkey_deinit(privkey);
702
fprintf_plus(stderr, "This OpenPGP key implies using"
703
" a GnuTLS security parameter \"%s\".\n",
704
safe_string(gnutls_sec_param_get_name
710
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
711
/* Err on the side of caution */
712
sec_param = GNUTLS_SEC_PARAM_ULTRA;
714
fprintf_plus(stderr, "Falling back to security parameter"
716
safe_string(gnutls_sec_param_get_name
721
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
725
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
726
" implies %u DH bits; using that.\n",
727
safe_string(gnutls_sec_param_get_name
732
fprintf_plus(stderr, "Failed to get implied number of DH"
733
" bits for security parameter \"%s\"): %s\n",
734
safe_string(gnutls_sec_param_get_name
736
safer_gnutls_strerror(ret));
740
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
743
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
744
if(ret != GNUTLS_E_SUCCESS){
745
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
746
" bits): %s\n", mc->dh_bits,
747
safer_gnutls_strerror(ret));
751
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);
757
gnutls_certificate_free_credentials(mc->cred);
758
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);
762
__attribute__((nonnull, warn_unused_result))
763
static int init_gnutls_session(gnutls_session_t *session,
481
static int init_gnutls_session(gnutls_session_t *session){
766
483
/* GnuTLS session creation */
819
537
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
820
538
__attribute__((unused)) const char *txt){}
822
/* Set effective uid to 0, return errno */
823
__attribute__((warn_unused_result))
824
int raise_privileges(void){
825
int old_errno = errno;
827
if(seteuid(0) == -1){
834
/* Set effective and real user ID to 0. Return errno. */
835
__attribute__((warn_unused_result))
836
int raise_privileges_permanently(void){
837
int old_errno = errno;
838
int ret = raise_privileges();
850
/* Set effective user ID to unprivileged saved user ID */
851
__attribute__((warn_unused_result))
852
int lower_privileges(void){
853
int old_errno = errno;
855
if(seteuid(uid) == -1){
862
/* Lower privileges permanently */
863
__attribute__((warn_unused_result))
864
int lower_privileges_permanently(void){
865
int old_errno = errno;
867
if(setuid(uid) == -1){
874
/* Helper function to add_local_route() and delete_local_route() */
875
__attribute__((nonnull, warn_unused_result))
876
static bool add_delete_local_route(const bool add,
878
AvahiIfIndex if_index){
880
char helper[] = "mandos-client-iprouteadddel";
881
char add_arg[] = "add";
882
char delete_arg[] = "delete";
883
char debug_flag[] = "--debug";
884
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
885
if(pluginhelperdir == NULL){
887
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
888
" variable not set; cannot run helper\n");
893
char interface[IF_NAMESIZE];
894
if(if_indextoname((unsigned int)if_index, interface) == NULL){
895
perror_plus("if_indextoname");
899
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
901
perror_plus("open(\"/dev/null\", O_RDONLY)");
907
/* Raise privileges */
908
errno = raise_privileges_permanently();
910
perror_plus("Failed to raise privileges");
911
/* _exit(EX_NOPERM); */
917
perror_plus("setgid");
920
/* Reset supplementary groups */
922
ret = setgroups(0, NULL);
924
perror_plus("setgroups");
928
ret = dup2(devnull, STDIN_FILENO);
930
perror_plus("dup2(devnull, STDIN_FILENO)");
933
ret = close(devnull);
935
perror_plus("close");
938
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
940
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
943
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
948
if(helperdir_fd == -1){
950
_exit(EX_UNAVAILABLE);
952
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
955
perror_plus("openat");
957
_exit(EX_UNAVAILABLE);
961
#pragma GCC diagnostic push
962
#pragma GCC diagnostic ignored "-Wcast-qual"
964
if(fexecve(helper_fd, (char *const [])
965
{ helper, add ? add_arg : delete_arg, (char *)address,
966
interface, debug ? debug_flag : NULL, NULL },
969
#pragma GCC diagnostic pop
971
perror_plus("fexecve");
983
pret = waitpid(pid, &status, 0);
984
if(pret == -1 and errno == EINTR and quit_now){
985
int errno_raising = 0;
986
if((errno = raise_privileges()) != 0){
987
errno_raising = errno;
988
perror_plus("Failed to raise privileges in order to"
989
" kill helper program");
991
if(kill(pid, SIGTERM) == -1){
994
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
995
perror_plus("Failed to lower privileges after killing"
1000
} while(pret == -1 and errno == EINTR);
1002
perror_plus("waitpid");
1005
if(WIFEXITED(status)){
1006
if(WEXITSTATUS(status) != 0){
1007
fprintf_plus(stderr, "Error: iprouteadddel exited"
1008
" with status %d\n", WEXITSTATUS(status));
1013
if(WIFSIGNALED(status)){
1014
fprintf_plus(stderr, "Error: iprouteadddel died by"
1015
" signal %d\n", WTERMSIG(status));
1018
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1022
__attribute__((nonnull, warn_unused_result))
1023
static bool add_local_route(const char *address,
1024
AvahiIfIndex if_index){
1026
fprintf_plus(stderr, "Adding route to %s\n", address);
1028
return add_delete_local_route(true, address, if_index);
1031
__attribute__((nonnull, warn_unused_result))
1032
static bool delete_local_route(const char *address,
1033
AvahiIfIndex if_index){
1035
fprintf_plus(stderr, "Removing route to %s\n", address);
1037
return add_delete_local_route(false, address, if_index);
1040
540
/* Called when a Mandos server is found */
1041
__attribute__((nonnull, warn_unused_result))
1042
static int start_mandos_communication(const char *ip, in_port_t port,
541
static int start_mandos_communication(const char *ip, uint16_t port,
1043
542
AvahiIfIndex if_index,
1044
int af, mandos_context *mc){
1045
544
int ret, tcp_sd = -1;
1047
struct sockaddr_storage to;
547
struct sockaddr_in in;
548
struct sockaddr_in6 in6;
1048
550
char *buffer = NULL;
1049
551
char *decrypted_buffer = NULL;
1050
552
size_t buffer_length = 0;
1178
651
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1179
652
char interface[IF_NAMESIZE];
1180
653
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1181
perror_plus("if_indextoname");
654
perror("if_indextoname");
1183
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1184
"\n", ip, interface, (uintmax_t)port);
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
1187
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1188
ip, (uintmax_t)port);
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1190
663
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1191
664
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1193
ret = getnameinfo((struct sockaddr *)&to,
1194
sizeof(struct sockaddr_in6),
1195
addrstr, sizeof(addrstr), NULL, 0,
1198
ret = getnameinfo((struct sockaddr *)&to,
1199
sizeof(struct sockaddr_in),
1200
addrstr, sizeof(addrstr), NULL, 0,
1203
if(ret == EAI_SYSTEM){
1204
perror_plus("getnameinfo");
1205
} else if(ret != 0) {
1206
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1207
} else if(strcmp(addrstr, ip) != 0){
1208
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1219
ret = connect(tcp_sd, (struct sockaddr *)&to,
1220
sizeof(struct sockaddr_in6));
1222
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1223
sizeof(struct sockaddr_in));
1226
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1227
and if_index != AVAHI_IF_UNSPEC
1228
and connect_to == NULL
1229
and not route_added and
1230
((af == AF_INET6 and not
1231
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1233
or (af == AF_INET and
1234
/* Not a a IPv4LL address */
1235
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1236
& 0xFFFF0000L) != 0xA9FE0000L))){
1237
/* Work around Avahi bug - Avahi does not announce link-local
1238
addresses if it has a global address, so local hosts with
1239
*only* a link-local address (e.g. Mandos clients) cannot
1240
connect to a Mandos server announced by Avahi on a server
1241
host with a global address. Work around this by retrying
1242
with an explicit route added with the server's address.
1244
Avahi bug reference:
1245
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1246
https://bugs.debian.org/587961
1249
fprintf_plus(stderr, "Mandos server unreachable, trying"
1253
route_added = add_local_route(ip, if_index);
1259
if(errno != ECONNREFUSED or debug){
1261
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){
1274
706
const char *out = mandos_protocol_version;
1629
1019
signal_received = sig;
1630
1020
int old_errno = errno;
1631
/* set main loop to exit */
1632
if(simple_poll != NULL){
1633
avahi_simple_poll_quit(simple_poll);
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1635
1024
errno = old_errno;
1638
__attribute__((nonnull, warn_unused_result))
1639
bool get_flags(const char *ifname, struct ifreq *ifr){
1643
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1646
perror_plus("socket");
1650
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1651
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1652
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1656
perror_plus("ioctl SIOCGIFFLAGS");
1666
__attribute__((nonnull, warn_unused_result))
1667
bool good_flags(const char *ifname, const struct ifreq *ifr){
1669
/* Reject the loopback device */
1670
if(ifr->ifr_flags & IFF_LOOPBACK){
1672
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1677
/* Accept point-to-point devices only if connect_to is specified */
1678
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1680
fprintf_plus(stderr, "Accepting point-to-point interface"
1681
" \"%s\"\n", ifname);
1685
/* Otherwise, reject non-broadcast-capable devices */
1686
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1688
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1689
" \"%s\"\n", ifname);
1693
/* Reject non-ARP interfaces (including dummy interfaces) */
1694
if(ifr->ifr_flags & IFF_NOARP){
1696
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1702
/* Accept this device */
1704
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1710
1028
* This function determines if a directory entry in /sys/class/net
1711
1029
* corresponds to an acceptable network device.
1712
1030
* (This function is passed to scandir(3) as a filter function.)
1714
__attribute__((nonnull, warn_unused_result))
1715
1032
int good_interface(const struct dirent *if_entry){
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1716
1041
if(if_entry->d_name[0] == '.'){
1721
if(not get_flags(if_entry->d_name, &ifr)){
1723
fprintf_plus(stderr, "Failed to get flags for interface "
1724
"\"%s\"\n", if_entry->d_name);
1729
if(not good_flags(if_entry->d_name, &ifr)){
1736
* This function determines if a network interface is up.
1738
__attribute__((nonnull, warn_unused_result))
1739
bool interface_is_up(const char *interface){
1741
if(not get_flags(interface, &ifr)){
1743
fprintf_plus(stderr, "Failed to get flags for interface "
1744
"\"%s\"\n", interface);
1749
return (bool)(ifr.ifr_flags & IFF_UP);
1753
* This function determines if a network interface is running
1755
__attribute__((nonnull, warn_unused_result))
1756
bool interface_is_running(const char *interface){
1758
if(not get_flags(interface, &ifr)){
1760
fprintf_plus(stderr, "Failed to get flags for interface "
1761
"\"%s\"\n", interface);
1766
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1769
__attribute__((nonnull, pure, warn_unused_result))
1770
int notdotentries(const struct dirent *direntry){
1771
/* Skip "." and ".." */
1772
if(direntry->d_name[0] == '.'
1773
and (direntry->d_name[1] == '\0'
1774
or (direntry->d_name[1] == '.'
1775
and direntry->d_name[2] == '\0'))){
1781
/* Is this directory entry a runnable program? */
1782
__attribute__((nonnull, warn_unused_result))
1783
int runnable_hook(const struct dirent *direntry){
1788
if((direntry->d_name)[0] == '\0'){
1793
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1794
"abcdefghijklmnopqrstuvwxyz"
1797
if((direntry->d_name)[sret] != '\0'){
1798
/* Contains non-allowed characters */
1800
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1806
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1809
perror_plus("Could not stat hook");
1813
if(not (S_ISREG(st.st_mode))){
1814
/* Not a regular file */
1816
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1821
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1822
/* Not executable */
1824
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 */
1830
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1836
__attribute__((nonnull, warn_unused_result))
1837
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1838
mandos_context *mc){
1840
struct timespec now;
1841
struct timespec waited_time;
1842
intmax_t block_time;
1845
if(mc->current_server == NULL){
1847
fprintf_plus(stderr, "Wait until first server is found."
1850
ret = avahi_simple_poll_iterate(s, -1);
1853
fprintf_plus(stderr, "Check current_server if we should run"
1856
/* the current time */
1857
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1859
perror_plus("clock_gettime");
1862
/* Calculating in ms how long time between now and server
1863
who we visted longest time ago. Now - last seen. */
1864
waited_time.tv_sec = (now.tv_sec
1865
- mc->current_server->last_seen.tv_sec);
1866
waited_time.tv_nsec = (now.tv_nsec
1867
- mc->current_server->last_seen.tv_nsec);
1868
/* total time is 10s/10,000ms.
1869
Converting to s from ms by dividing by 1,000,
1870
and ns to ms by dividing by 1,000,000. */
1871
block_time = ((retry_interval
1872
- ((intmax_t)waited_time.tv_sec * 1000))
1873
- ((intmax_t)waited_time.tv_nsec / 1000000));
1876
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1880
if(block_time <= 0){
1881
ret = start_mandos_communication(mc->current_server->ip,
1882
mc->current_server->port,
1883
mc->current_server->if_index,
1884
mc->current_server->af, mc);
1886
avahi_simple_poll_quit(s);
1889
ret = clock_gettime(CLOCK_MONOTONIC,
1890
&mc->current_server->last_seen);
1892
perror_plus("clock_gettime");
1895
mc->current_server = mc->current_server->next;
1896
block_time = 0; /* Call avahi to find new Mandos
1897
servers, but don't block */
1900
ret = avahi_simple_poll_iterate(s, (int)block_time);
1903
if(ret > 0 or errno != EINTR){
1904
return (ret != 1) ? ret : 0;
1910
__attribute__((nonnull))
1911
void run_network_hooks(const char *mode, const char *interface,
1913
struct dirent **direntries = NULL;
1914
if(hookdir_fd == -1){
1915
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1917
if(hookdir_fd == -1){
1918
if(errno == ENOENT){
1920
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1921
" found\n", hookdir);
1924
perror_plus("open");
1929
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1931
perror_plus("open(\"/dev/null\", O_RDONLY)");
1934
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1935
runnable_hook, alphasort);
1937
perror_plus("scandir");
1941
struct dirent *direntry;
1943
for(int i = 0; i < numhooks; i++){
1944
direntry = direntries[i];
1946
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1949
pid_t hook_pid = fork();
1952
/* Raise privileges */
1953
errno = raise_privileges_permanently();
1955
perror_plus("Failed to raise privileges");
1962
perror_plus("setgid");
1965
/* Reset supplementary groups */
1967
ret = setgroups(0, NULL);
1969
perror_plus("setgroups");
1972
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1974
perror_plus("setenv");
1977
ret = setenv("DEVICE", interface, 1);
1979
perror_plus("setenv");
1982
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1984
perror_plus("setenv");
1987
ret = setenv("MODE", mode, 1);
1989
perror_plus("setenv");
1993
ret = asprintf(&delaystring, "%f", (double)delay);
1995
perror_plus("asprintf");
1998
ret = setenv("DELAY", delaystring, 1);
2001
perror_plus("setenv");
2005
if(connect_to != NULL){
2006
ret = setenv("CONNECT", connect_to, 1);
2008
perror_plus("setenv");
2012
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2016
perror_plus("openat");
2017
_exit(EXIT_FAILURE);
2019
if(close(hookdir_fd) == -1){
2020
perror_plus("close");
2021
_exit(EXIT_FAILURE);
2023
ret = dup2(devnull, STDIN_FILENO);
2025
perror_plus("dup2(devnull, STDIN_FILENO)");
2028
ret = close(devnull);
2030
perror_plus("close");
2033
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2035
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2038
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2040
perror_plus("fexecve");
2041
_exit(EXIT_FAILURE);
2045
perror_plus("fork");
2050
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2051
perror_plus("waitpid");
2055
if(WIFEXITED(status)){
2056
if(WEXITSTATUS(status) != 0){
2057
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2058
" with status %d\n", direntry->d_name,
2059
WEXITSTATUS(status));
2063
} else if(WIFSIGNALED(status)){
2064
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2065
" signal %d\n", direntry->d_name,
2070
fprintf_plus(stderr, "Warning: network hook \"%s\""
2071
" crashed\n", direntry->d_name);
2077
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2083
if(close(hookdir_fd) == -1){
2084
perror_plus("close");
2091
__attribute__((nonnull, warn_unused_result))
2092
int bring_up_interface(const char *const interface,
2094
int old_errno = errno;
2096
struct ifreq network;
2097
unsigned int if_index = if_nametoindex(interface);
2099
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2109
if(not interface_is_up(interface)){
2111
int ioctl_errno = 0;
2112
if(not get_flags(interface, &network)){
2114
fprintf_plus(stderr, "Failed to get flags for interface "
2115
"\"%s\"\n", interface);
2119
network.ifr_flags |= IFF_UP; /* set flag */
2121
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2124
perror_plus("socket");
2132
perror_plus("close");
2139
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2143
/* Raise privileges */
2144
ret_errno = raise_privileges();
2147
perror_plus("Failed to raise privileges");
2152
bool restore_loglevel = false;
2154
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2155
messages about the network interface to mess up the prompt */
2156
ret_linux = klogctl(8, NULL, 5);
2157
if(ret_linux == -1){
2158
perror_plus("klogctl");
2160
restore_loglevel = true;
2163
#endif /* __linux__ */
2164
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2165
ioctl_errno = errno;
2167
if(restore_loglevel){
2168
ret_linux = klogctl(7, NULL, 0);
2169
if(ret_linux == -1){
2170
perror_plus("klogctl");
2173
#endif /* __linux__ */
2175
/* If raise_privileges() succeeded above */
2177
/* Lower privileges */
2178
ret_errno = lower_privileges();
2181
perror_plus("Failed to lower privileges");
2185
/* Close the socket */
2188
perror_plus("close");
2191
if(ret_setflags == -1){
2192
errno = ioctl_errno;
2193
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2198
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2202
/* Sleep checking until interface is running.
2203
Check every 0.25s, up to total time of delay */
2204
for(int i = 0; i < delay * 4; i++){
2205
if(interface_is_running(interface)){
2208
struct timespec sleeptime = { .tv_nsec = 250000000 };
2209
ret = nanosleep(&sleeptime, NULL);
2210
if(ret == -1 and errno != EINTR){
2211
perror_plus("nanosleep");
2219
__attribute__((nonnull, warn_unused_result))
2220
int take_down_interface(const char *const interface){
2221
int old_errno = errno;
2222
struct ifreq network;
2223
unsigned int if_index = if_nametoindex(interface);
2225
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2229
if(interface_is_up(interface)){
2231
int ioctl_errno = 0;
2232
if(not get_flags(interface, &network) and debug){
2234
fprintf_plus(stderr, "Failed to get flags for interface "
2235
"\"%s\"\n", interface);
2239
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2241
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2244
perror_plus("socket");
2250
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2254
/* Raise privileges */
2255
ret_errno = raise_privileges();
2258
perror_plus("Failed to raise privileges");
2261
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2262
ioctl_errno = errno;
2264
/* If raise_privileges() succeeded above */
2266
/* Lower privileges */
2267
ret_errno = lower_privileges();
2270
perror_plus("Failed to lower privileges");
2274
/* Close the socket */
2275
int ret = close(sd);
2277
perror_plus("close");
2280
if(ret_setflags == -1){
2281
errno = ioctl_errno;
2282
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2287
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2295
1122
int main(int argc, char *argv[]){
2296
mandos_context mc = { .server = NULL, .dh_bits = 0,
2297
.priority = "SECURE256:!CTYPE-X.509"
2298
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2299
.current_server = NULL, .interfaces = NULL,
2300
.interfaces_size = 0 };
2301
1123
AvahiSServiceBrowser *sb = NULL;
2304
1126
intmax_t tmpmax;
2306
1128
int exitcode = EXIT_SUCCESS;
2307
char *interfaces_to_take_down = NULL;
2308
size_t interfaces_to_take_down_size = 0;
2309
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2310
char old_tempdir[] = "/tmp/mandosXXXXXX";
2311
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;
2312
1137
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2313
1138
const char *seckey = PATHDIR "/" SECKEY;
2314
1139
const char *pubkey = PATHDIR "/" PUBKEY;
2315
const char *dh_params_file = NULL;
2316
char *interfaces_hooks = NULL;
2318
1141
bool gnutls_initialized = false;
2319
1142
bool gpgme_initialized = false;
2320
1143
float delay = 2.5f;
2321
double retry_interval = 10; /* 10s between trying a server and
2322
retrying the same server again */
2324
1145
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2325
1146
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2505
/* Work around Debian bug #633582:
2506
<https://bugs.debian.org/633582> */
2508
/* Re-raise privileges */
2509
ret = raise_privileges();
2512
perror_plus("Failed to raise privileges");
2516
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2517
int seckey_fd = open(seckey, O_RDONLY);
2518
if(seckey_fd == -1){
2519
perror_plus("open");
2521
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2523
perror_plus("fstat");
2525
if(S_ISREG(st.st_mode)
2526
and st.st_uid == 0 and st.st_gid == 0){
2527
ret = fchown(seckey_fd, uid, gid);
2529
perror_plus("fchown");
2537
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2538
int pubkey_fd = open(pubkey, O_RDONLY);
2539
if(pubkey_fd == -1){
2540
perror_plus("open");
2542
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2544
perror_plus("fstat");
2546
if(S_ISREG(st.st_mode)
2547
and st.st_uid == 0 and st.st_gid == 0){
2548
ret = fchown(pubkey_fd, uid, gid);
2550
perror_plus("fchown");
2558
if(dh_params_file != NULL
2559
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2560
int dhparams_fd = open(dh_params_file, O_RDONLY);
2561
if(dhparams_fd == -1){
2562
perror_plus("open");
2564
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2566
perror_plus("fstat");
2568
if(S_ISREG(st.st_mode)
2569
and st.st_uid == 0 and st.st_gid == 0){
2570
ret = fchown(dhparams_fd, uid, gid);
2572
perror_plus("fchown");
2580
/* Lower privileges */
2581
ret = lower_privileges();
2584
perror_plus("Failed to lower privileges");
2589
/* Remove invalid interface names (except "none") */
2591
char *interface = NULL;
2592
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2594
if(strcmp(interface, "none") != 0
2595
and if_nametoindex(interface) == 0){
2596
if(interface[0] != '\0'){
2597
fprintf_plus(stderr, "Not using nonexisting interface"
2598
" \"%s\"\n", interface);
2600
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2606
/* Run network hooks */
2608
if(mc.interfaces != NULL){
2609
interfaces_hooks = malloc(mc.interfaces_size);
2610
if(interfaces_hooks == NULL){
2611
perror_plus("malloc");
2614
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2615
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2617
run_network_hooks("start", interfaces_hooks != NULL ?
2618
interfaces_hooks : "", delay);
2622
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;
2625
1323
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2626
1324
from the signal handler */
2627
1325
/* Initialize the pseudo-RNG for Avahi */
2628
1326
srand((unsigned int) time(NULL));
2629
simple_poll = avahi_simple_poll_new();
2630
if(simple_poll == NULL){
2631
fprintf_plus(stderr,
2632
"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");
2633
1330
exitcode = EX_UNAVAILABLE;
2660
1357
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2662
perror_plus("sigaction");
1359
perror("sigaction");
2663
1360
return EX_OSERR;
2665
1362
if(old_sigterm_action.sa_handler != SIG_IGN){
2666
1363
ret = sigaction(SIGINT, &sigterm_action, NULL);
2668
perror_plus("sigaction");
1365
perror("sigaction");
2669
1366
exitcode = EX_OSERR;
2673
1370
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2675
perror_plus("sigaction");
1372
perror("sigaction");
2676
1373
return EX_OSERR;
2678
1375
if(old_sigterm_action.sa_handler != SIG_IGN){
2679
1376
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2681
perror_plus("sigaction");
1378
perror("sigaction");
2682
1379
exitcode = EX_OSERR;
2686
1383
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2688
perror_plus("sigaction");
1385
perror("sigaction");
2689
1386
return EX_OSERR;
2691
1388
if(old_sigterm_action.sa_handler != SIG_IGN){
2692
1389
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2694
perror_plus("sigaction");
1391
perror("sigaction");
2695
1392
exitcode = EX_OSERR;
2700
/* If no interfaces were specified, make a list */
2701
if(mc.interfaces == NULL){
2702
struct dirent **direntries = NULL;
2703
/* Look for any good interfaces */
2704
ret = scandir(sys_class_net, &direntries, good_interface,
2707
/* Add all found interfaces to interfaces list */
2708
for(int i = 0; i < ret; ++i){
2709
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2710
direntries[i]->d_name);
2713
perror_plus("argz_add");
2714
free(direntries[i]);
2718
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2719
direntries[i]->d_name);
2721
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 */
2728
fprintf_plus(stderr, "Could not find a network interface\n");
2729
exitcode = EXIT_FAILURE;
2734
/* Bring up interfaces which are down, and remove any "none"s */
2736
char *interface = NULL;
2737
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2739
/* If interface name is "none", stop bringing up interfaces.
2740
Also remove all instances of "none" from the list */
2741
if(strcmp(interface, "none") == 0){
2742
argz_delete(&mc.interfaces, &mc.interfaces_size,
2745
while((interface = argz_next(mc.interfaces,
2746
mc.interfaces_size, interface))){
2747
if(strcmp(interface, "none") == 0){
2748
argz_delete(&mc.interfaces, &mc.interfaces_size,
2755
bool interface_was_up = interface_is_up(interface);
2756
errno = bring_up_interface(interface, delay);
2757
if(not interface_was_up){
2759
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2760
" %s\n", interface, strerror(errno));
2762
errno = argz_add(&interfaces_to_take_down,
2763
&interfaces_to_take_down_size,
2766
perror_plus("argz_add");
2771
if(debug and (interfaces_to_take_down == NULL)){
2772
fprintf_plus(stderr, "No interfaces were brought up\n");
2776
/* If we only got one interface, explicitly use only that one */
2777
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2779
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2782
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1533
/* Lower privileges permanently */
2789
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1545
ret = init_gnutls_global(pubkey, seckey);
2791
fprintf_plus(stderr, "init_gnutls_global failed\n");
1547
fprintf(stderr, "init_gnutls_global failed\n");
2792
1548
exitcode = EX_UNAVAILABLE;
2994
1719
gpgme_release(mc.ctx);
2997
/* Cleans up the circular linked list of Mandos servers the client
2999
if(mc.current_server != NULL){
3000
mc.current_server->prev->next = NULL;
3001
while(mc.current_server != NULL){
3002
server *next = mc.current_server->next;
3004
#pragma GCC diagnostic push
3005
#pragma GCC diagnostic ignored "-Wcast-qual"
3007
free((char *)(mc.current_server->ip));
3009
#pragma GCC diagnostic pop
3011
free(mc.current_server);
3012
mc.current_server = next;
3016
/* Re-raise privileges */
3018
ret = raise_privileges();
3021
perror_plus("Failed to raise privileges");
3024
/* Run network hooks */
3025
run_network_hooks("stop", interfaces_hooks != NULL ?
3026
interfaces_hooks : "", delay);
3028
/* Take down the network interfaces which were brought up */
3030
char *interface = NULL;
3031
while((interface = argz_next(interfaces_to_take_down,
3032
interfaces_to_take_down_size,
3034
ret = take_down_interface(interface);
3037
perror_plus("Failed to take down interface");
3040
if(debug and (interfaces_to_take_down == NULL)){
3041
fprintf_plus(stderr, "No interfaces needed to be taken"
3047
ret = lower_privileges_permanently();
3050
perror_plus("Failed to lower privileges permanently");
3054
free(interfaces_to_take_down);
3055
free(interfaces_hooks);
3057
void clean_dir_at(int base, const char * const dirname,
3059
struct dirent **direntries = NULL;
3061
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3067
perror_plus("open");
3070
int numentries = scandirat(dir_fd, ".", &direntries,
3071
notdotentries, alphasort);
3072
if(numentries >= 0){
3073
for(int i = 0; i < numentries; i++){
3075
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3076
dirname, direntries[i]->d_name);
3078
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3080
if(errno == EISDIR){
3081
dret = unlinkat(dir_fd, direntries[i]->d_name,
3084
if((dret == -1) and (errno == ENOTEMPTY)
3085
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3086
== 0) and (level == 0)){
3087
/* Recurse only in this special case */
3088
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3091
if((dret == -1) and (errno != ENOENT)){
3092
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3093
direntries[i]->d_name, strerror(errno));
3096
free(direntries[i]);
3099
/* need to clean even if 0 because man page doesn't specify */
3101
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3102
if(dret == -1 and errno != ENOENT){
3103
perror_plus("rmdir");
3106
perror_plus("scandirat");
3111
/* Removes the GPGME temp directory and all files inside */
3112
if(tempdir != NULL){
3113
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){