9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
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
12
* Copyright © 2008-2018 Teddy Hogeborn
13
* Copyright © 2008-2018 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
21
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
25
* General Public License for more details.
25
27
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
* Contact the authors at <mandos@recompile.se>.
32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
33
34
#ifndef _LARGEFILE_SOURCE
34
35
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
36
37
#ifndef _FILE_OFFSET_BITS
37
38
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
40
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
46
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
49
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
51
53
#include <sys/ioctl.h> /* ioctl */
52
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
55
sockaddr_in6, PF_INET6,
54
56
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open() */
58
#include <sys/stat.h> /* open(), S_ISREG */
57
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
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() */
67
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
75
SIOCSIFFLAGS, if_indextoname(),
69
76
if_nametoindex(), IF_NAMESIZE */
120
139
#define PATHDIR "/conf/conf.d/mandos"
121
140
#define SECKEY "seckey.txt"
122
141
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
124
144
bool debug = false;
125
145
static const char mandos_protocol_version[] = "1";
126
146
const char *argp_program_version = "mandos-client " VERSION;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
147
const char *argp_program_bug_address = "<mandos@recompile.se>";
148
static const char sys_class_net[] = "/sys/class/net";
149
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;
129
166
/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
132
168
AvahiServer *server;
133
169
gnutls_certificate_credentials_t cred;
134
170
unsigned int dh_bits;
135
171
gnutls_dh_params_t dh_params;
136
172
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
138
177
} mandos_context;
140
/* global context so signal handler can reach it*/
141
mandos_context mc = { .simple_poll = NULL, .server = NULL,
142
.dh_bits = 1024, .priority = "SECURE256"
143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
145
182
sig_atomic_t quit_now = 0;
146
183
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));
149
205
* Make additional room in "buffer" for at least BUFFER_SIZE more
150
206
* bytes. "buffer_capacity" is how much is currently allocated,
151
207
* "buffer_length" is how much is already used.
209
__attribute__((nonnull, warn_unused_result))
153
210
size_t incbuffer(char **buffer, size_t buffer_length,
154
size_t buffer_capacity){
211
size_t buffer_capacity){
155
212
if(buffer_length + BUFFER_SIZE > buffer_capacity){
156
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
160
222
buffer_capacity += BUFFER_SIZE;
162
224
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;
166
276
* Initialize GPGME.
168
static bool init_gpgme(const char *seckey,
169
const char *pubkey, const char *tempdir){
278
__attribute__((nonnull, warn_unused_result))
279
static bool init_gpgme(const char * const seckey,
280
const char * const pubkey,
281
const char * const tempdir,
170
283
gpgme_error_t rc;
171
284
gpgme_engine_info_t engine_info;
175
287
* Helper function to insert pub and seckey to the engine keyring.
177
bool import_key(const char *filename){
289
bool import_key(const char * const filename){
180
292
gpgme_data_t pgp_data;
182
294
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
188
300
rc = gpgme_data_new_from_fd(&pgp_data, fd);
189
301
if(rc != GPG_ERR_NO_ERROR){
190
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
191
gpgme_strsource(rc), gpgme_strerror(rc));
302
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
303
gpgme_strsource(rc), gpgme_strerror(rc));
195
rc = gpgme_op_import(mc.ctx, pgp_data);
307
rc = gpgme_op_import(mc->ctx, pgp_data);
196
308
if(rc != GPG_ERR_NO_ERROR){
197
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
198
gpgme_strsource(rc), gpgme_strerror(rc));
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
202
ret = (int)TEMP_FAILURE_RETRY(close(fd));
316
perror_plus("close");
206
318
gpgme_data_release(pgp_data);
211
fprintf(stderr, "Initializing GPGME\n");
323
fprintf_plus(stderr, "Initializing GPGME\n");
215
327
gpgme_check_version(NULL);
216
328
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
217
329
if(rc != GPG_ERR_NO_ERROR){
218
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
219
gpgme_strsource(rc), gpgme_strerror(rc));
330
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
331
gpgme_strsource(rc), gpgme_strerror(rc));
223
/* Set GPGME home directory for the OpenPGP engine only */
335
/* Set GPGME home directory for the OpenPGP engine only */
224
336
rc = gpgme_get_engine_info(&engine_info);
225
337
if(rc != GPG_ERR_NO_ERROR){
226
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
227
gpgme_strsource(rc), gpgme_strerror(rc));
338
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
339
gpgme_strsource(rc), gpgme_strerror(rc));
230
342
while(engine_info != NULL){
269
385
ssize_t plaintext_length = 0;
272
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
388
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
275
391
/* Create new GPGME data buffer from memory cryptotext */
276
392
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
278
394
if(rc != GPG_ERR_NO_ERROR){
279
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
280
gpgme_strsource(rc), gpgme_strerror(rc));
395
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
396
gpgme_strsource(rc), gpgme_strerror(rc));
284
400
/* Create new empty GPGME data buffer for the plaintext */
285
401
rc = gpgme_data_new(&dh_plain);
286
402
if(rc != GPG_ERR_NO_ERROR){
287
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
288
gpgme_strsource(rc), gpgme_strerror(rc));
403
fprintf_plus(stderr, "Mandos plugin mandos-client: "
404
"bad gpgme_data_new: %s: %s\n",
405
gpgme_strsource(rc), gpgme_strerror(rc));
289
406
gpgme_data_release(dh_crypto);
293
410
/* Decrypt data from the cryptotext data buffer to the plaintext
295
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
412
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
296
413
if(rc != GPG_ERR_NO_ERROR){
297
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
298
gpgme_strsource(rc), gpgme_strerror(rc));
414
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
415
gpgme_strsource(rc), gpgme_strerror(rc));
299
416
plaintext_length = -1;
301
418
gpgme_decrypt_result_t result;
302
result = gpgme_op_decrypt_result(mc.ctx);
419
result = gpgme_op_decrypt_result(mc->ctx);
303
420
if(result == NULL){
304
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
421
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
306
fprintf(stderr, "Unsupported algorithm: %s\n",
307
result->unsupported_algorithm);
308
fprintf(stderr, "Wrong key usage: %u\n",
309
result->wrong_key_usage);
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
427
if(result->file_name != NULL){
311
fprintf(stderr, "File name: %s\n", result->file_name);
428
fprintf_plus(stderr, "File name: %s\n", result->file_name);
313
430
gpgme_recipient_t recipient;
314
431
recipient = result->recipients;
315
432
while(recipient != NULL){
316
fprintf(stderr, "Public key algorithm: %s\n",
317
gpgme_pubkey_algo_name(recipient->pubkey_algo));
318
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
319
fprintf(stderr, "Secret key available: %s\n",
320
recipient->status == GPG_ERR_NO_SECKEY
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
322
440
recipient = recipient->next;
421
542
/* OpenPGP credentials */
422
gnutls_certificate_allocate_credentials(&mc.cred);
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
423
544
if(ret != GNUTLS_E_SUCCESS){
424
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
428
safer_gnutls_strerror(ret));
429
gnutls_global_deinit();
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
546
safer_gnutls_strerror(ret));
434
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
435
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
551
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
552
" secret key %s as GnuTLS credentials\n",
439
557
ret = gnutls_certificate_set_openpgp_key_file
440
(mc.cred, pubkeyfilename, seckeyfilename,
558
(mc->cred, pubkeyfilename, seckeyfilename,
441
559
GNUTLS_OPENPGP_FMT_BASE64);
442
560
if(ret != GNUTLS_E_SUCCESS){
444
"Error[%d] while reading the OpenPGP key pair ('%s',"
445
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
446
fprintf(stderr, "The GnuTLS error is: %s\n",
447
safer_gnutls_strerror(ret));
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));
451
569
/* GnuTLS server initialization */
452
ret = gnutls_dh_params_init(&mc.dh_params);
453
if(ret != GNUTLS_E_SUCCESS){
454
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
455
" %s\n", safer_gnutls_strerror(ret));
458
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
459
if(ret != GNUTLS_E_SUCCESS){
460
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
461
safer_gnutls_strerror(ret));
465
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
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);
471
gnutls_certificate_free_credentials(mc.cred);
472
gnutls_global_deinit();
473
gnutls_dh_params_deinit(mc.dh_params);
757
gnutls_certificate_free_credentials(mc->cred);
758
gnutls_dh_params_deinit(mc->dh_params);
477
static int init_gnutls_session(gnutls_session_t *session){
762
__attribute__((nonnull, warn_unused_result))
763
static int init_gnutls_session(gnutls_session_t *session,
479
766
/* GnuTLS session creation */
533
819
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
534
820
__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);
536
1040
/* Called when a Mandos server is found */
537
static int start_mandos_communication(const char *ip, uint16_t port,
1041
__attribute__((nonnull, warn_unused_result))
1042
static int start_mandos_communication(const char *ip, in_port_t port,
538
1043
AvahiIfIndex if_index,
1044
int af, mandos_context *mc){
540
1045
int ret, tcp_sd = -1;
543
struct sockaddr_in in;
544
struct sockaddr_in6 in6;
1047
struct sockaddr_storage to;
546
1048
char *buffer = NULL;
547
1049
char *decrypted_buffer = NULL;
548
1050
size_t buffer_length = 0;
567
fprintf(stderr, "Bad address family: %d\n", af);
1073
fprintf_plus(stderr, "Bad address family: %d\n", af);
571
ret = init_gnutls_session(&session);
1078
/* If the interface is specified and we have a list of interfaces */
1079
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1080
/* Check if the interface is one of the interfaces we are using */
1083
char *interface = NULL;
1084
while((interface = argz_next(mc->interfaces,
1085
mc->interfaces_size,
1087
if(if_nametoindex(interface) == (unsigned int)if_index){
1094
/* This interface does not match any in the list, so we don't
1095
connect to the server */
1097
char interface[IF_NAMESIZE];
1098
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1099
perror_plus("if_indextoname");
1101
fprintf_plus(stderr, "Skipping server on non-used interface"
1103
if_indextoname((unsigned int)if_index,
1111
ret = init_gnutls_session(&session, mc);
577
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1117
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1118
PRIuMAX "\n", ip, (uintmax_t)port);
581
tcp_sd = socket(pf, SOCK_STREAM, 0);
1121
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1124
perror_plus("socket");
584
1126
goto mandos_end;
588
1131
goto mandos_end;
591
memset(&to, 0, sizeof(to));
592
1134
if(af == AF_INET6){
593
to.in6.sin6_family = (sa_family_t)af;
594
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1135
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1136
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1137
ret = inet_pton(af, ip, &to6->sin6_addr);
595
1138
} else { /* IPv4 */
596
to.in.sin_family = (sa_family_t)af;
597
ret = inet_pton(af, ip, &to.in.sin_addr);
1139
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1140
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1141
ret = inet_pton(af, ip, &to4->sin_addr);
1145
perror_plus("inet_pton");
601
1147
goto mandos_end;
604
fprintf(stderr, "Bad address: %s\n", ip);
1151
fprintf_plus(stderr, "Bad address: %s\n", ip);
605
1153
goto mandos_end;
607
1155
if(af == AF_INET6){
608
to.in6.sin6_port = htons(port); /* Spurious warnings from
610
-Wunreachable-code */
612
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
613
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
1156
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1157
if(IN6_IS_ADDR_LINKLOCAL
1158
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
615
1159
if(if_index == AVAHI_IF_UNSPEC){
616
fprintf(stderr, "An IPv6 link-local address is incomplete"
617
" without a network interface\n");
1160
fprintf_plus(stderr, "An IPv6 link-local address is"
1161
" incomplete without a network interface\n");
618
1163
goto mandos_end;
620
1165
/* Set the network interface number as scope */
621
to.in6.sin6_scope_id = (uint32_t)if_index;
1166
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
624
to.in.sin_port = htons(port); /* Spurious warnings from
626
-Wunreachable-code */
1169
((struct sockaddr_in *)&to)->sin_port = htons(port);
630
1174
goto mandos_end;
634
1178
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
635
1179
char interface[IF_NAMESIZE];
636
1180
if(if_indextoname((unsigned int)if_index, interface) == NULL){
637
perror("if_indextoname");
1181
perror_plus("if_indextoname");
639
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
640
ip, interface, port);
1183
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1184
"\n", ip, interface, (uintmax_t)port);
643
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1187
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1188
ip, (uintmax_t)port);
646
1190
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
647
1191
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
650
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
653
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
659
if(strcmp(addrstr, ip) != 0){
660
fprintf(stderr, "Canonical address form: %s\n", addrstr);
670
ret = connect(tcp_sd, &to.in6, sizeof(to));
672
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
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");
683
1274
const char *out = mandos_protocol_version;
969
1629
signal_received = sig;
970
1630
int old_errno = errno;
971
if(mc.simple_poll != NULL){
972
avahi_simple_poll_quit(mc.simple_poll);
1631
/* set main loop to exit */
1632
if(simple_poll != NULL){
1633
avahi_simple_poll_quit(simple_poll);
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
* This function determines if a directory entry in /sys/class/net
1711
* corresponds to an acceptable network device.
1712
* (This function is passed to scandir(3) as a filter function.)
1714
__attribute__((nonnull, warn_unused_result))
1715
int good_interface(const struct dirent *if_entry){
1716
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",
1830
fprintf_plus(stderr, "Hook \"%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",
977
2295
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 };
978
2301
AvahiSServiceBrowser *sb = NULL;
981
2304
intmax_t tmpmax;
983
2306
int exitcode = EXIT_SUCCESS;
984
const char *interface = "eth0";
985
struct ifreq network;
987
bool take_down_interface = false;
990
char *connect_to = NULL;
991
char tempdir[] = "/tmp/mandosXXXXXX";
992
bool tempdir_created = false;
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;
993
2312
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
994
2313
const char *seckey = PATHDIR "/" SECKEY;
995
2314
const char *pubkey = PATHDIR "/" PUBKEY;
2315
const char *dh_params_file = NULL;
2316
char *interfaces_hooks = NULL;
997
2318
bool gnutls_initialized = false;
998
2319
bool gpgme_initialized = false;
999
2320
float delay = 2.5f;
2321
double retry_interval = 10; /* 10s between trying a server and
2322
retrying the same server again */
1001
2324
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1002
2325
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1095
2447
delay = strtof(arg, &tmp);
1096
2448
if(errno != 0 or tmp == arg or *tmp != '\0'){
1097
fprintf(stderr, "Bad delay\n");
2449
argp_error(state, "Bad delay");
2451
case 132: /* --retry */
2453
retry_interval = strtod(arg, &tmp);
2454
if(errno != 0 or tmp == arg or *tmp != '\0'
2455
or (retry_interval * 1000) > INT_MAX
2456
or retry_interval < 0){
2457
argp_error(state, "Bad retry interval");
2460
case 133: /* --network-hook-dir */
2464
* These reproduce what we would get without ARGP_NO_HELP
2466
case '?': /* --help */
2467
argp_state_help(state, state->out_stream,
2468
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2469
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2470
case -3: /* --usage */
2471
argp_state_help(state, state->out_stream,
2472
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2473
case 'V': /* --version */
2474
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2475
exit(argp_err_exit_status);
1106
2478
return ARGP_ERR_UNKNOWN;
1111
2483
struct argp argp = { .options = options, .parser = parse_opt,
1112
2484
.args_doc = "",
1113
2485
.doc = "Mandos client -- Get and decrypt"
1114
2486
" passwords from a Mandos server" };
1115
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1116
if(ret == ARGP_ERR_UNKNOWN){
1117
fprintf(stderr, "Unknown error while parsing arguments\n");
1118
exitcode = EXIT_FAILURE;
2487
ret_errno = argp_parse(&argp, argc, argv,
2488
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2495
perror_plus("argp_parse");
2496
exitcode = EX_OSERR;
2499
exitcode = EX_USAGE;
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);
1161
2660
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1163
perror("sigaction");
1164
return EXIT_FAILURE;
2662
perror_plus("sigaction");
1166
2665
if(old_sigterm_action.sa_handler != SIG_IGN){
1167
2666
ret = sigaction(SIGINT, &sigterm_action, NULL);
1169
perror("sigaction");
1170
exitcode = EXIT_FAILURE;
2668
perror_plus("sigaction");
2669
exitcode = EX_OSERR;
1174
2673
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1176
perror("sigaction");
1177
return EXIT_FAILURE;
2675
perror_plus("sigaction");
1179
2678
if(old_sigterm_action.sa_handler != SIG_IGN){
1180
2679
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1182
perror("sigaction");
1183
exitcode = EXIT_FAILURE;
2681
perror_plus("sigaction");
2682
exitcode = EX_OSERR;
1187
2686
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1189
perror("sigaction");
1190
return EXIT_FAILURE;
2688
perror_plus("sigaction");
1192
2691
if(old_sigterm_action.sa_handler != SIG_IGN){
1193
2692
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1195
perror("sigaction");
1196
exitcode = EXIT_FAILURE;
1201
/* If the interface is down, bring it up */
1202
if(interface[0] != '\0'){
1203
if_index = (AvahiIfIndex) if_nametoindex(interface);
1205
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1206
exitcode = EXIT_FAILURE;
1214
/* Re-raise priviliges */
1222
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1223
messages to mess up the prompt */
1224
ret = klogctl(8, NULL, 5);
1225
bool restore_loglevel = true;
1227
restore_loglevel = false;
1230
#endif /* __linux__ */
1232
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1235
exitcode = EXIT_FAILURE;
1237
if(restore_loglevel){
1238
ret = klogctl(7, NULL, 0);
1243
#endif /* __linux__ */
1244
/* Lower privileges */
1252
strcpy(network.ifr_name, interface);
1253
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1255
perror("ioctl SIOCGIFFLAGS");
1257
if(restore_loglevel){
1258
ret = klogctl(7, NULL, 0);
1263
#endif /* __linux__ */
1264
exitcode = EXIT_FAILURE;
1265
/* Lower privileges */
1273
if((network.ifr_flags & IFF_UP) == 0){
1274
network.ifr_flags |= IFF_UP;
1275
take_down_interface = true;
1276
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1278
take_down_interface = false;
1279
perror("ioctl SIOCSIFFLAGS");
1280
exitcode = EXIT_FAILURE;
1282
if(restore_loglevel){
1283
ret = klogctl(7, NULL, 0);
2694
perror_plus("sigaction");
2695
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]);
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,
1288
#endif /* __linux__ */
1289
/* Lower privileges */
1298
/* sleep checking until interface is running */
1299
for(int i=0; i < delay * 4; i++){
1300
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1302
perror("ioctl SIOCGIFFLAGS");
1303
} else if(network.ifr_flags & IFF_RUNNING){
1306
struct timespec sleeptime = { .tv_nsec = 250000000 };
1307
ret = nanosleep(&sleeptime, NULL);
1308
if(ret == -1 and errno != EINTR){
1309
perror("nanosleep");
1312
if(not take_down_interface){
1313
/* We won't need the socket anymore */
1314
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1320
if(restore_loglevel){
1321
/* Restores kernel loglevel to default */
1322
ret = klogctl(7, NULL, 0);
1327
#endif /* __linux__ */
1328
/* Lower privileges */
1330
if(take_down_interface){
1331
/* Lower privileges */
1337
/* Lower privileges permanently */
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);
1349
ret = init_gnutls_global(pubkey, seckey);
2789
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1351
fprintf(stderr, "init_gnutls_global failed\n");
1352
exitcode = EXIT_FAILURE;
2791
fprintf_plus(stderr, "init_gnutls_global failed\n");
2792
exitcode = EX_UNAVAILABLE;
1355
2795
gnutls_initialized = true;
1517
2994
gpgme_release(mc.ctx);
1520
/* Take down the network interface */
1521
if(take_down_interface){
1522
/* Re-raise priviliges */
1529
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1531
perror("ioctl SIOCGIFFLAGS");
1532
} else if(network.ifr_flags & IFF_UP) {
1533
network.ifr_flags &= ~IFF_UP; /* clear flag */
1534
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1536
perror("ioctl SIOCSIFFLAGS");
1539
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1543
/* Lower privileges permanently */
1552
/* Removes the temp directory used by GPGME */
1553
if(tempdir_created){
1555
struct dirent *direntry;
1556
d = opendir(tempdir);
1558
if(errno != ENOENT){
1563
direntry = readdir(d);
1564
if(direntry == NULL){
1567
/* Skip "." and ".." */
1568
if(direntry->d_name[0] == '.'
1569
and (direntry->d_name[1] == '\0'
1570
or (direntry->d_name[1] == '.'
1571
and direntry->d_name[2] == '\0'))){
1574
char *fullname = NULL;
1575
ret = asprintf(&fullname, "%s/%s", tempdir,
1581
ret = remove(fullname);
1583
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1590
ret = rmdir(tempdir);
1591
if(ret == -1 and errno != ENOENT){
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);
1597
3117
sigemptyset(&old_sigterm_action.sa_mask);
1598
3118
old_sigterm_action.sa_handler = SIG_DFL;
1599
ret = sigaction(signal_received, &old_sigterm_action, NULL);
3119
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3120
&old_sigterm_action,
1601
perror("sigaction");
1603
raise(signal_received);
3123
perror_plus("sigaction");
3126
ret = raise(signal_received);
3127
} while(ret != 0 and errno == EINTR);
3129
perror_plus("raise");
3132
TEMP_FAILURE_RETRY(pause());
1606
3135
return exitcode;