9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008-2018 Teddy Hogeborn
13
* Copyright © 2008-2018 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
12
* Copyright © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
20
* This program is distributed in the hope that it will be useful, but
23
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
24
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25
23
* General Public License for more details.
27
25
* You should have received a copy of the GNU General Public License
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
30
* Contact the authors at <mandos@recompile.se>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
33
32
/* Needed by GPGME, specifically gpgme_data_seek() */
34
33
#ifndef _LARGEFILE_SOURCE
35
34
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
37
36
#ifndef _FILE_OFFSET_BITS
38
37
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
41
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
43
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
46
45
#include <stddef.h> /* NULL, size_t, ssize_t */
47
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 */
73
#include <time.h> /* nanosleep(), time(), sleep() */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
74
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
75
68
SIOCSIFFLAGS, if_indextoname(),
76
69
if_nametoindex(), IF_NAMESIZE */
139
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
if(result->unsupported_algorithm != NULL) {
424
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
425
result->unsupported_algorithm);
427
fprintf_plus(stderr, "Wrong key usage: %s\n",
428
result->wrong_key_usage ? "Yes" : "No");
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
429
314
if(result->file_name != NULL){
430
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
fprintf(stderr, "File name: %s\n", result->file_name);
432
317
gpgme_recipient_t recipient;
433
318
recipient = result->recipients;
434
319
while(recipient != NULL){
435
fprintf_plus(stderr, "Public key algorithm: %s\n",
436
gpgme_pubkey_algo_name
437
(recipient->pubkey_algo));
438
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
439
fprintf_plus(stderr, "Secret key available: %s\n",
440
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
442
326
recipient = recipient->next;
544
425
/* OpenPGP credentials */
545
ret = gnutls_certificate_allocate_credentials(&mc->cred);
426
gnutls_certificate_allocate_credentials(&mc.cred);
546
427
if(ret != GNUTLS_E_SUCCESS){
547
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
548
safer_gnutls_strerror(ret));
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
432
safer_gnutls_strerror(ret));
433
gnutls_global_deinit();
553
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
554
" 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,
559
443
ret = gnutls_certificate_set_openpgp_key_file
560
(mc->cred, pubkeyfilename, seckeyfilename,
444
(mc.cred, pubkeyfilename, seckeyfilename,
561
445
GNUTLS_OPENPGP_FMT_BASE64);
562
446
if(ret != GNUTLS_E_SUCCESS){
564
"Error[%d] while reading the OpenPGP key pair ('%s',"
565
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
566
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
567
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));
571
455
/* GnuTLS server initialization */
572
ret = gnutls_dh_params_init(&mc->dh_params);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
575
" initialization: %s\n",
576
safer_gnutls_strerror(ret));
579
/* If a Diffie-Hellman parameters file was given, try to use it */
580
if(dhparamsfilename != NULL){
581
gnutls_datum_t params = { .data = NULL, .size = 0 };
583
int dhpfile = open(dhparamsfilename, O_RDONLY);
586
dhparamsfilename = NULL;
589
size_t params_capacity = 0;
591
params_capacity = incbuffer((char **)¶ms.data,
593
(size_t)params_capacity);
594
if(params_capacity == 0){
595
perror_plus("incbuffer");
598
dhparamsfilename = NULL;
601
ssize_t bytes_read = read(dhpfile,
602
params.data + params.size,
608
/* check bytes_read for failure */
613
dhparamsfilename = NULL;
616
params.size += (unsigned int)bytes_read;
618
ret = close(dhpfile);
620
perror_plus("close");
622
if(params.data == NULL){
623
dhparamsfilename = NULL;
625
if(dhparamsfilename == NULL){
628
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
629
GNUTLS_X509_FMT_PEM);
630
if(ret != GNUTLS_E_SUCCESS){
631
fprintf_plus(stderr, "Failed to parse DH parameters in file"
632
" \"%s\": %s\n", dhparamsfilename,
633
safer_gnutls_strerror(ret));
634
dhparamsfilename = NULL;
639
if(dhparamsfilename == NULL){
640
if(mc->dh_bits == 0){
641
/* Find out the optimal number of DH bits */
642
/* Try to read the private key file */
643
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
645
int secfile = open(seckeyfilename, O_RDONLY);
650
size_t buffer_capacity = 0;
652
buffer_capacity = incbuffer((char **)&buffer.data,
654
(size_t)buffer_capacity);
655
if(buffer_capacity == 0){
656
perror_plus("incbuffer");
661
ssize_t bytes_read = read(secfile,
662
buffer.data + buffer.size,
668
/* check bytes_read for failure */
675
buffer.size += (unsigned int)bytes_read;
679
/* If successful, use buffer to parse private key */
680
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
681
if(buffer.data != NULL){
683
gnutls_openpgp_privkey_t privkey = NULL;
684
ret = gnutls_openpgp_privkey_init(&privkey);
685
if(ret != GNUTLS_E_SUCCESS){
686
fprintf_plus(stderr, "Error initializing OpenPGP key"
688
safer_gnutls_strerror(ret));
692
ret = gnutls_openpgp_privkey_import
693
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
694
if(ret != GNUTLS_E_SUCCESS){
695
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
696
safer_gnutls_strerror(ret));
702
/* Use private key to suggest an appropriate
704
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
705
gnutls_openpgp_privkey_deinit(privkey);
707
fprintf_plus(stderr, "This OpenPGP key implies using"
708
" a GnuTLS security parameter \"%s\".\n",
709
safe_string(gnutls_sec_param_get_name
715
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
716
/* Err on the side of caution */
717
sec_param = GNUTLS_SEC_PARAM_ULTRA;
719
fprintf_plus(stderr, "Falling back to security parameter"
721
safe_string(gnutls_sec_param_get_name
726
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
730
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
731
" implies %u DH bits; using that.\n",
732
safe_string(gnutls_sec_param_get_name
737
fprintf_plus(stderr, "Failed to get implied number of DH"
738
" bits for security parameter \"%s\"): %s\n",
739
safe_string(gnutls_sec_param_get_name
741
safer_gnutls_strerror(ret));
745
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
748
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
749
if(ret != GNUTLS_E_SUCCESS){
750
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
751
" bits): %s\n", mc->dh_bits,
752
safer_gnutls_strerror(ret));
756
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);
762
gnutls_certificate_free_credentials(mc->cred);
763
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);
767
__attribute__((nonnull, warn_unused_result))
768
static int init_gnutls_session(gnutls_session_t *session,
481
static int init_gnutls_session(gnutls_session_t *session){
771
483
/* GnuTLS session creation */
824
537
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
825
538
__attribute__((unused)) const char *txt){}
827
/* Set effective uid to 0, return errno */
828
__attribute__((warn_unused_result))
829
int raise_privileges(void){
830
int old_errno = errno;
832
if(seteuid(0) == -1){
839
/* Set effective and real user ID to 0. Return errno. */
840
__attribute__((warn_unused_result))
841
int raise_privileges_permanently(void){
842
int old_errno = errno;
843
int ret = raise_privileges();
855
/* Set effective user ID to unprivileged saved user ID */
856
__attribute__((warn_unused_result))
857
int lower_privileges(void){
858
int old_errno = errno;
860
if(seteuid(uid) == -1){
867
/* Lower privileges permanently */
868
__attribute__((warn_unused_result))
869
int lower_privileges_permanently(void){
870
int old_errno = errno;
872
if(setuid(uid) == -1){
879
/* Helper function to add_local_route() and delete_local_route() */
880
__attribute__((nonnull, warn_unused_result))
881
static bool add_delete_local_route(const bool add,
883
AvahiIfIndex if_index){
885
char helper[] = "mandos-client-iprouteadddel";
886
char add_arg[] = "add";
887
char delete_arg[] = "delete";
888
char debug_flag[] = "--debug";
889
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
890
if(pluginhelperdir == NULL){
892
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
893
" variable not set; cannot run helper\n");
898
char interface[IF_NAMESIZE];
899
if(if_indextoname((unsigned int)if_index, interface) == NULL){
900
perror_plus("if_indextoname");
904
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
906
perror_plus("open(\"/dev/null\", O_RDONLY)");
912
/* Raise privileges */
913
errno = raise_privileges_permanently();
915
perror_plus("Failed to raise privileges");
916
/* _exit(EX_NOPERM); */
922
perror_plus("setgid");
925
/* Reset supplementary groups */
927
ret = setgroups(0, NULL);
929
perror_plus("setgroups");
933
ret = dup2(devnull, STDIN_FILENO);
935
perror_plus("dup2(devnull, STDIN_FILENO)");
938
ret = close(devnull);
940
perror_plus("close");
943
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
945
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
948
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
953
if(helperdir_fd == -1){
955
_exit(EX_UNAVAILABLE);
957
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
960
perror_plus("openat");
962
_exit(EX_UNAVAILABLE);
966
#pragma GCC diagnostic push
967
#pragma GCC diagnostic ignored "-Wcast-qual"
969
if(fexecve(helper_fd, (char *const [])
970
{ helper, add ? add_arg : delete_arg, (char *)address,
971
interface, debug ? debug_flag : NULL, NULL },
974
#pragma GCC diagnostic pop
976
perror_plus("fexecve");
988
pret = waitpid(pid, &status, 0);
989
if(pret == -1 and errno == EINTR and quit_now){
990
int errno_raising = 0;
991
if((errno = raise_privileges()) != 0){
992
errno_raising = errno;
993
perror_plus("Failed to raise privileges in order to"
994
" kill helper program");
996
if(kill(pid, SIGTERM) == -1){
999
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1000
perror_plus("Failed to lower privileges after killing"
1005
} while(pret == -1 and errno == EINTR);
1007
perror_plus("waitpid");
1010
if(WIFEXITED(status)){
1011
if(WEXITSTATUS(status) != 0){
1012
fprintf_plus(stderr, "Error: iprouteadddel exited"
1013
" with status %d\n", WEXITSTATUS(status));
1018
if(WIFSIGNALED(status)){
1019
fprintf_plus(stderr, "Error: iprouteadddel died by"
1020
" signal %d\n", WTERMSIG(status));
1023
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1027
__attribute__((nonnull, warn_unused_result))
1028
static bool add_local_route(const char *address,
1029
AvahiIfIndex if_index){
1031
fprintf_plus(stderr, "Adding route to %s\n", address);
1033
return add_delete_local_route(true, address, if_index);
1036
__attribute__((nonnull, warn_unused_result))
1037
static bool delete_local_route(const char *address,
1038
AvahiIfIndex if_index){
1040
fprintf_plus(stderr, "Removing route to %s\n", address);
1042
return add_delete_local_route(false, address, if_index);
1045
540
/* Called when a Mandos server is found */
1046
__attribute__((nonnull, warn_unused_result))
1047
static int start_mandos_communication(const char *ip, in_port_t port,
541
static int start_mandos_communication(const char *ip, uint16_t port,
1048
542
AvahiIfIndex if_index,
1049
int af, mandos_context *mc){
1050
544
int ret, tcp_sd = -1;
1052
struct sockaddr_storage to;
547
struct sockaddr_in in;
548
struct sockaddr_in6 in6;
1053
550
char *buffer = NULL;
1054
551
char *decrypted_buffer = NULL;
1055
552
size_t buffer_length = 0;
1183
651
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1184
652
char interface[IF_NAMESIZE];
1185
653
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1186
perror_plus("if_indextoname");
654
perror("if_indextoname");
1188
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1189
"\n", ip, interface, (uintmax_t)port);
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
1192
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1193
ip, (uintmax_t)port);
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1195
663
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1196
664
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1198
ret = getnameinfo((struct sockaddr *)&to,
1199
sizeof(struct sockaddr_in6),
1200
addrstr, sizeof(addrstr), NULL, 0,
1203
ret = getnameinfo((struct sockaddr *)&to,
1204
sizeof(struct sockaddr_in),
1205
addrstr, sizeof(addrstr), NULL, 0,
1208
if(ret == EAI_SYSTEM){
1209
perror_plus("getnameinfo");
1210
} else if(ret != 0) {
1211
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1212
} else if(strcmp(addrstr, ip) != 0){
1213
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1224
ret = connect(tcp_sd, (struct sockaddr *)&to,
1225
sizeof(struct sockaddr_in6));
1227
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1228
sizeof(struct sockaddr_in));
1231
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1232
and if_index != AVAHI_IF_UNSPEC
1233
and connect_to == NULL
1234
and not route_added and
1235
((af == AF_INET6 and not
1236
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1238
or (af == AF_INET and
1239
/* Not a a IPv4LL address */
1240
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1241
& 0xFFFF0000L) != 0xA9FE0000L))){
1242
/* Work around Avahi bug - Avahi does not announce link-local
1243
addresses if it has a global address, so local hosts with
1244
*only* a link-local address (e.g. Mandos clients) cannot
1245
connect to a Mandos server announced by Avahi on a server
1246
host with a global address. Work around this by retrying
1247
with an explicit route added with the server's address.
1249
Avahi bug reference:
1250
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1251
https://bugs.debian.org/587961
1254
fprintf_plus(stderr, "Mandos server unreachable, trying"
1258
route_added = add_local_route(ip, if_index);
1264
if(errno != ECONNREFUSED or debug){
1266
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 */
1279
704
const char *out = mandos_protocol_version;
1634
1017
signal_received = sig;
1635
1018
int old_errno = errno;
1636
/* set main loop to exit */
1637
if(simple_poll != NULL){
1638
avahi_simple_poll_quit(simple_poll);
1019
if(mc.simple_poll != NULL){
1020
avahi_simple_poll_quit(mc.simple_poll);
1640
1022
errno = old_errno;
1643
__attribute__((nonnull, warn_unused_result))
1644
bool get_flags(const char *ifname, struct ifreq *ifr){
1648
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1651
perror_plus("socket");
1655
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1656
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1657
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1661
perror_plus("ioctl SIOCGIFFLAGS");
1664
if((close(s) == -1) and debug){
1666
perror_plus("close");
1671
if((close(s) == -1) and debug){
1673
perror_plus("close");
1679
__attribute__((nonnull, warn_unused_result))
1680
bool good_flags(const char *ifname, const struct ifreq *ifr){
1682
/* Reject the loopback device */
1683
if(ifr->ifr_flags & IFF_LOOPBACK){
1685
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1690
/* Accept point-to-point devices only if connect_to is specified */
1691
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1693
fprintf_plus(stderr, "Accepting point-to-point interface"
1694
" \"%s\"\n", ifname);
1698
/* Otherwise, reject non-broadcast-capable devices */
1699
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1701
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1702
" \"%s\"\n", ifname);
1706
/* Reject non-ARP interfaces (including dummy interfaces) */
1707
if(ifr->ifr_flags & IFF_NOARP){
1709
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1715
/* Accept this device */
1717
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1723
1026
* This function determines if a directory entry in /sys/class/net
1724
1027
* corresponds to an acceptable network device.
1725
1028
* (This function is passed to scandir(3) as a filter function.)
1727
__attribute__((nonnull, warn_unused_result))
1728
1030
int good_interface(const struct dirent *if_entry){
1032
char *flagname = NULL;
1033
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1729
1039
if(if_entry->d_name[0] == '.'){
1734
if(not get_flags(if_entry->d_name, &ifr)){
1736
fprintf_plus(stderr, "Failed to get flags for interface "
1737
"\"%s\"\n", if_entry->d_name);
1742
if(not good_flags(if_entry->d_name, &ifr)){
1749
* This function determines if a network interface is up.
1751
__attribute__((nonnull, warn_unused_result))
1752
bool interface_is_up(const char *interface){
1754
if(not get_flags(interface, &ifr)){
1756
fprintf_plus(stderr, "Failed to get flags for interface "
1757
"\"%s\"\n", interface);
1762
return (bool)(ifr.ifr_flags & IFF_UP);
1766
* This function determines if a network interface is running
1768
__attribute__((nonnull, warn_unused_result))
1769
bool interface_is_running(const char *interface){
1771
if(not get_flags(interface, &ifr)){
1773
fprintf_plus(stderr, "Failed to get flags for interface "
1774
"\"%s\"\n", interface);
1779
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1782
__attribute__((nonnull, pure, warn_unused_result))
1783
int notdotentries(const struct dirent *direntry){
1784
/* Skip "." and ".." */
1785
if(direntry->d_name[0] == '.'
1786
and (direntry->d_name[1] == '\0'
1787
or (direntry->d_name[1] == '.'
1788
and direntry->d_name[2] == '\0'))){
1794
/* Is this directory entry a runnable program? */
1795
__attribute__((nonnull, warn_unused_result))
1796
int runnable_hook(const struct dirent *direntry){
1801
if((direntry->d_name)[0] == '\0'){
1806
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1807
"abcdefghijklmnopqrstuvwxyz"
1810
if((direntry->d_name)[sret] != '\0'){
1811
/* Contains non-allowed characters */
1813
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1819
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1822
perror_plus("Could not stat hook");
1826
if(not (S_ISREG(st.st_mode))){
1827
/* Not a regular file */
1829
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1834
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1835
/* Not executable */
1837
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1042
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1047
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1048
/* read line from flags_fd */
1049
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1050
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1051
flagstring[(size_t)to_read] = '\0';
1052
if(flagstring == NULL){
1058
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1075
tmpmax = strtoimax(flagstring, &tmp, 0);
1076
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1077
and not (isspace(*tmp)))
1078
or tmpmax != (ifreq_flags)tmpmax){
1080
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1081
flagstring, if_entry->d_name);
1087
ifreq_flags flags = (ifreq_flags)tmpmax;
1088
/* Reject the loopback device */
1089
if(flags & IFF_LOOPBACK){
1091
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1096
/* Accept point-to-point devices only if connect_to is specified */
1097
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1099
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1104
/* Otherwise, reject non-broadcast-capable devices */
1105
if(not (flags & IFF_BROADCAST)){
1107
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1112
/* Accept this device */
1843
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1114
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1849
__attribute__((nonnull, warn_unused_result))
1850
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1851
mandos_context *mc){
1853
struct timespec now;
1854
struct timespec waited_time;
1855
intmax_t block_time;
1858
if(mc->current_server == NULL){
1860
fprintf_plus(stderr, "Wait until first server is found."
1863
ret = avahi_simple_poll_iterate(s, -1);
1866
fprintf_plus(stderr, "Check current_server if we should run"
1869
/* the current time */
1870
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1872
perror_plus("clock_gettime");
1875
/* Calculating in ms how long time between now and server
1876
who we visted longest time ago. Now - last seen. */
1877
waited_time.tv_sec = (now.tv_sec
1878
- mc->current_server->last_seen.tv_sec);
1879
waited_time.tv_nsec = (now.tv_nsec
1880
- mc->current_server->last_seen.tv_nsec);
1881
/* total time is 10s/10,000ms.
1882
Converting to s from ms by dividing by 1,000,
1883
and ns to ms by dividing by 1,000,000. */
1884
block_time = ((retry_interval
1885
- ((intmax_t)waited_time.tv_sec * 1000))
1886
- ((intmax_t)waited_time.tv_nsec / 1000000));
1889
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1893
if(block_time <= 0){
1894
ret = start_mandos_communication(mc->current_server->ip,
1895
mc->current_server->port,
1896
mc->current_server->if_index,
1897
mc->current_server->af, mc);
1899
avahi_simple_poll_quit(s);
1902
ret = clock_gettime(CLOCK_MONOTONIC,
1903
&mc->current_server->last_seen);
1905
perror_plus("clock_gettime");
1908
mc->current_server = mc->current_server->next;
1909
block_time = 0; /* Call avahi to find new Mandos
1910
servers, but don't block */
1913
ret = avahi_simple_poll_iterate(s, (int)block_time);
1916
if(ret > 0 or errno != EINTR){
1917
return (ret != 1) ? ret : 0;
1923
__attribute__((nonnull))
1924
void run_network_hooks(const char *mode, const char *interface,
1926
struct dirent **direntries = NULL;
1927
if(hookdir_fd == -1){
1928
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1930
if(hookdir_fd == -1){
1931
if(errno == ENOENT){
1933
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1934
" found\n", hookdir);
1937
perror_plus("open");
1942
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1944
perror_plus("open(\"/dev/null\", O_RDONLY)");
1947
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1948
runnable_hook, alphasort);
1950
perror_plus("scandir");
1954
struct dirent *direntry;
1956
for(int i = 0; i < numhooks; i++){
1957
direntry = direntries[i];
1959
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1962
pid_t hook_pid = fork();
1965
/* Raise privileges */
1966
errno = raise_privileges_permanently();
1968
perror_plus("Failed to raise privileges");
1975
perror_plus("setgid");
1978
/* Reset supplementary groups */
1980
ret = setgroups(0, NULL);
1982
perror_plus("setgroups");
1985
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1987
perror_plus("setenv");
1990
ret = setenv("DEVICE", interface, 1);
1992
perror_plus("setenv");
1995
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1997
perror_plus("setenv");
2000
ret = setenv("MODE", mode, 1);
2002
perror_plus("setenv");
2006
ret = asprintf(&delaystring, "%f", (double)delay);
2008
perror_plus("asprintf");
2011
ret = setenv("DELAY", delaystring, 1);
2014
perror_plus("setenv");
2018
if(connect_to != NULL){
2019
ret = setenv("CONNECT", connect_to, 1);
2021
perror_plus("setenv");
2025
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2029
perror_plus("openat");
2030
_exit(EXIT_FAILURE);
2032
if(close(hookdir_fd) == -1){
2033
perror_plus("close");
2034
_exit(EXIT_FAILURE);
2036
ret = dup2(devnull, STDIN_FILENO);
2038
perror_plus("dup2(devnull, STDIN_FILENO)");
2041
ret = close(devnull);
2043
perror_plus("close");
2046
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2048
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2051
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2053
perror_plus("fexecve");
2054
_exit(EXIT_FAILURE);
2058
perror_plus("fork");
2063
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2064
perror_plus("waitpid");
2068
if(WIFEXITED(status)){
2069
if(WEXITSTATUS(status) != 0){
2070
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2071
" with status %d\n", direntry->d_name,
2072
WEXITSTATUS(status));
2076
} else if(WIFSIGNALED(status)){
2077
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2078
" signal %d\n", direntry->d_name,
2083
fprintf_plus(stderr, "Warning: network hook \"%s\""
2084
" crashed\n", direntry->d_name);
2090
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2096
if(close(hookdir_fd) == -1){
2097
perror_plus("close");
2104
__attribute__((nonnull, warn_unused_result))
2105
int bring_up_interface(const char *const interface,
2107
int old_errno = errno;
2109
struct ifreq network;
2110
unsigned int if_index = if_nametoindex(interface);
2112
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2122
if(not interface_is_up(interface)){
2124
int ioctl_errno = 0;
2125
if(not get_flags(interface, &network)){
2127
fprintf_plus(stderr, "Failed to get flags for interface "
2128
"\"%s\"\n", interface);
2132
network.ifr_flags |= IFF_UP; /* set flag */
2134
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2137
perror_plus("socket");
2145
perror_plus("close");
2152
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2156
/* Raise privileges */
2157
ret_errno = raise_privileges();
2160
perror_plus("Failed to raise privileges");
2165
bool restore_loglevel = false;
2167
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2168
messages about the network interface to mess up the prompt */
2169
ret_linux = klogctl(8, NULL, 5);
2170
if(ret_linux == -1){
2171
perror_plus("klogctl");
2173
restore_loglevel = true;
2176
#endif /* __linux__ */
2177
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2178
ioctl_errno = errno;
2180
if(restore_loglevel){
2181
ret_linux = klogctl(7, NULL, 0);
2182
if(ret_linux == -1){
2183
perror_plus("klogctl");
2186
#endif /* __linux__ */
2188
/* If raise_privileges() succeeded above */
2190
/* Lower privileges */
2191
ret_errno = lower_privileges();
2194
perror_plus("Failed to lower privileges");
2198
/* Close the socket */
2201
perror_plus("close");
2204
if(ret_setflags == -1){
2205
errno = ioctl_errno;
2206
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2211
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2215
/* Sleep checking until interface is running.
2216
Check every 0.25s, up to total time of delay */
2217
for(int i = 0; i < delay * 4; i++){
2218
if(interface_is_running(interface)){
2221
struct timespec sleeptime = { .tv_nsec = 250000000 };
2222
ret = nanosleep(&sleeptime, NULL);
2223
if(ret == -1 and errno != EINTR){
2224
perror_plus("nanosleep");
2232
__attribute__((nonnull, warn_unused_result))
2233
int take_down_interface(const char *const interface){
2234
int old_errno = errno;
2235
struct ifreq network;
2236
unsigned int if_index = if_nametoindex(interface);
2238
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2242
if(interface_is_up(interface)){
2244
int ioctl_errno = 0;
2245
if(not get_flags(interface, &network) and debug){
2247
fprintf_plus(stderr, "Failed to get flags for interface "
2248
"\"%s\"\n", interface);
2252
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2254
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2257
perror_plus("socket");
2263
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2267
/* Raise privileges */
2268
ret_errno = raise_privileges();
2271
perror_plus("Failed to raise privileges");
2274
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2275
ioctl_errno = errno;
2277
/* If raise_privileges() succeeded above */
2279
/* Lower privileges */
2280
ret_errno = lower_privileges();
2283
perror_plus("Failed to lower privileges");
2287
/* Close the socket */
2288
int ret = close(sd);
2290
perror_plus("close");
2293
if(ret_setflags == -1){
2294
errno = ioctl_errno;
2295
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2300
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2308
1120
int main(int argc, char *argv[]){
2309
mandos_context mc = { .server = NULL, .dh_bits = 0,
2310
.priority = "SECURE256:!CTYPE-X.509"
2311
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2312
.current_server = NULL, .interfaces = NULL,
2313
.interfaces_size = 0 };
2314
1121
AvahiSServiceBrowser *sb = NULL;
2317
1124
intmax_t tmpmax;
2319
1126
int exitcode = EXIT_SUCCESS;
2320
char *interfaces_to_take_down = NULL;
2321
size_t interfaces_to_take_down_size = 0;
2322
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2323
char old_tempdir[] = "/tmp/mandosXXXXXX";
2324
char *tempdir = NULL;
1127
const char *interface = "";
1128
struct ifreq network;
1130
bool take_down_interface = false;
1133
char tempdir[] = "/tmp/mandosXXXXXX";
1134
bool tempdir_created = false;
2325
1135
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2326
1136
const char *seckey = PATHDIR "/" SECKEY;
2327
1137
const char *pubkey = PATHDIR "/" PUBKEY;
2328
const char *dh_params_file = NULL;
2329
char *interfaces_hooks = NULL;
2331
1139
bool gnutls_initialized = false;
2332
1140
bool gpgme_initialized = false;
2333
1141
float delay = 2.5f;
2334
double retry_interval = 10; /* 10s between trying a server and
2335
retrying the same server again */
2337
1143
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2338
1144
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2518
/* Work around Debian bug #633582:
2519
<https://bugs.debian.org/633582> */
2521
/* Re-raise privileges */
2522
ret = raise_privileges();
2525
perror_plus("Failed to raise privileges");
2529
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2530
int seckey_fd = open(seckey, O_RDONLY);
2531
if(seckey_fd == -1){
2532
perror_plus("open");
2534
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2536
perror_plus("fstat");
2538
if(S_ISREG(st.st_mode)
2539
and st.st_uid == 0 and st.st_gid == 0){
2540
ret = fchown(seckey_fd, uid, gid);
2542
perror_plus("fchown");
2550
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2551
int pubkey_fd = open(pubkey, O_RDONLY);
2552
if(pubkey_fd == -1){
2553
perror_plus("open");
2555
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2557
perror_plus("fstat");
2559
if(S_ISREG(st.st_mode)
2560
and st.st_uid == 0 and st.st_gid == 0){
2561
ret = fchown(pubkey_fd, uid, gid);
2563
perror_plus("fchown");
2571
if(dh_params_file != NULL
2572
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2573
int dhparams_fd = open(dh_params_file, O_RDONLY);
2574
if(dhparams_fd == -1){
2575
perror_plus("open");
2577
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2579
perror_plus("fstat");
2581
if(S_ISREG(st.st_mode)
2582
and st.st_uid == 0 and st.st_gid == 0){
2583
ret = fchown(dhparams_fd, uid, gid);
2585
perror_plus("fchown");
2593
/* Lower privileges */
2594
ret = lower_privileges();
2597
perror_plus("Failed to lower privileges");
2602
/* Remove invalid interface names (except "none") */
2604
char *interface = NULL;
2605
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2607
if(strcmp(interface, "none") != 0
2608
and if_nametoindex(interface) == 0){
2609
if(interface[0] != '\0'){
2610
fprintf_plus(stderr, "Not using nonexisting interface"
2611
" \"%s\"\n", interface);
2613
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2619
/* Run network hooks */
2621
if(mc.interfaces != NULL){
2622
interfaces_hooks = malloc(mc.interfaces_size);
2623
if(interfaces_hooks == NULL){
2624
perror_plus("malloc");
2627
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2628
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2630
run_network_hooks("start", interfaces_hooks != NULL ?
2631
interfaces_hooks : "", delay);
2635
1293
avahi_set_log_function(empty_log);
1296
if(interface[0] == '\0'){
1297
struct dirent **direntries;
1298
ret = scandir(sys_class_net, &direntries, good_interface,
1301
/* Pick the first good interface */
1302
interface = strdup(direntries[0]->d_name);
1304
fprintf(stderr, "Using interface \"%s\"\n", interface);
1306
if(interface == NULL){
1309
exitcode = EXIT_FAILURE;
1315
fprintf(stderr, "Could not find a network interface\n");
1316
exitcode = EXIT_FAILURE;
2638
1321
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2639
1322
from the signal handler */
2640
1323
/* Initialize the pseudo-RNG for Avahi */
2641
1324
srand((unsigned int) time(NULL));
2642
simple_poll = avahi_simple_poll_new();
2643
if(simple_poll == NULL){
2644
fprintf_plus(stderr,
2645
"Avahi: Failed to create simple poll object.\n");
1325
mc.simple_poll = avahi_simple_poll_new();
1326
if(mc.simple_poll == NULL){
1327
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2646
1328
exitcode = EX_UNAVAILABLE;
2673
1355
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2675
perror_plus("sigaction");
1357
perror("sigaction");
2676
1358
return EX_OSERR;
2678
1360
if(old_sigterm_action.sa_handler != SIG_IGN){
2679
1361
ret = sigaction(SIGINT, &sigterm_action, NULL);
2681
perror_plus("sigaction");
1363
perror("sigaction");
2682
1364
exitcode = EX_OSERR;
2686
1368
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2688
perror_plus("sigaction");
1370
perror("sigaction");
2689
1371
return EX_OSERR;
2691
1373
if(old_sigterm_action.sa_handler != SIG_IGN){
2692
1374
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2694
perror_plus("sigaction");
1376
perror("sigaction");
2695
1377
exitcode = EX_OSERR;
2699
1381
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2701
perror_plus("sigaction");
1383
perror("sigaction");
2702
1384
return EX_OSERR;
2704
1386
if(old_sigterm_action.sa_handler != SIG_IGN){
2705
1387
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2707
perror_plus("sigaction");
1389
perror("sigaction");
2708
1390
exitcode = EX_OSERR;
2713
/* If no interfaces were specified, make a list */
2714
if(mc.interfaces == NULL){
2715
struct dirent **direntries = NULL;
2716
/* Look for any good interfaces */
2717
ret = scandir(sys_class_net, &direntries, good_interface,
2720
/* Add all found interfaces to interfaces list */
2721
for(int i = 0; i < ret; ++i){
2722
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2723
direntries[i]->d_name);
2726
perror_plus("argz_add");
2727
free(direntries[i]);
2731
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2732
direntries[i]->d_name);
2734
free(direntries[i]);
1395
/* If the interface is down, bring it up */
1396
if(strcmp(interface, "none") != 0){
1397
if_index = (AvahiIfIndex) if_nametoindex(interface);
1399
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1400
exitcode = EX_UNAVAILABLE;
1408
/* Re-raise priviliges */
1416
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1417
messages about the network interface to mess up the prompt */
1418
ret = klogctl(8, NULL, 5);
1419
bool restore_loglevel = true;
1421
restore_loglevel = false;
1424
#endif /* __linux__ */
1426
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1429
exitcode = EX_OSERR;
1431
if(restore_loglevel){
1432
ret = klogctl(7, NULL, 0);
1437
#endif /* __linux__ */
1438
/* Lower privileges */
1446
strcpy(network.ifr_name, interface);
1447
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1449
perror("ioctl SIOCGIFFLAGS");
1451
if(restore_loglevel){
1452
ret = klogctl(7, NULL, 0);
1457
#endif /* __linux__ */
1458
exitcode = EX_OSERR;
1459
/* Lower privileges */
1467
if((network.ifr_flags & IFF_UP) == 0){
1468
network.ifr_flags |= IFF_UP;
1469
take_down_interface = true;
1470
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1472
take_down_interface = false;
1473
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1474
exitcode = EX_OSERR;
1476
if(restore_loglevel){
1477
ret = klogctl(7, NULL, 0);
1482
#endif /* __linux__ */
1483
/* Lower privileges */
1492
/* sleep checking until interface is running */
1493
for(int i=0; i < delay * 4; i++){
1494
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1496
perror("ioctl SIOCGIFFLAGS");
1497
} else if(network.ifr_flags & IFF_RUNNING){
1500
struct timespec sleeptime = { .tv_nsec = 250000000 };
1501
ret = nanosleep(&sleeptime, NULL);
1502
if(ret == -1 and errno != EINTR){
1503
perror("nanosleep");
1506
if(not take_down_interface){
1507
/* We won't need the socket anymore */
1508
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1514
if(restore_loglevel){
1515
/* Restores kernel loglevel to default */
1516
ret = klogctl(7, NULL, 0);
1521
#endif /* __linux__ */
1522
/* Lower privileges */
1524
if(take_down_interface){
1525
/* Lower privileges */
2741
fprintf_plus(stderr, "Could not find a network interface\n");
2742
exitcode = EXIT_FAILURE;
2747
/* Bring up interfaces which are down, and remove any "none"s */
2749
char *interface = NULL;
2750
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2752
/* If interface name is "none", stop bringing up interfaces.
2753
Also remove all instances of "none" from the list */
2754
if(strcmp(interface, "none") == 0){
2755
argz_delete(&mc.interfaces, &mc.interfaces_size,
2758
while((interface = argz_next(mc.interfaces,
2759
mc.interfaces_size, interface))){
2760
if(strcmp(interface, "none") == 0){
2761
argz_delete(&mc.interfaces, &mc.interfaces_size,
2768
bool interface_was_up = interface_is_up(interface);
2769
errno = bring_up_interface(interface, delay);
2770
if(not interface_was_up){
2772
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2773
" %s\n", interface, strerror(errno));
2775
errno = argz_add(&interfaces_to_take_down,
2776
&interfaces_to_take_down_size,
2779
perror_plus("argz_add");
2784
if(debug and (interfaces_to_take_down == NULL)){
2785
fprintf_plus(stderr, "No interfaces were brought up\n");
2789
/* If we only got one interface, explicitly use only that one */
2790
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2792
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2795
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1531
/* Lower privileges permanently */
2802
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1543
ret = init_gnutls_global(pubkey, seckey);
2804
fprintf_plus(stderr, "init_gnutls_global failed\n");
1545
fprintf(stderr, "init_gnutls_global failed\n");
2805
1546
exitcode = EX_UNAVAILABLE;
3007
1729
gpgme_release(mc.ctx);
3010
/* Cleans up the circular linked list of Mandos servers the client
3012
if(mc.current_server != NULL){
3013
mc.current_server->prev->next = NULL;
3014
while(mc.current_server != NULL){
3015
server *next = mc.current_server->next;
3017
#pragma GCC diagnostic push
3018
#pragma GCC diagnostic ignored "-Wcast-qual"
3020
free((char *)(mc.current_server->ip));
3022
#pragma GCC diagnostic pop
3024
free(mc.current_server);
3025
mc.current_server = next;
3029
/* Re-raise privileges */
3031
ret = raise_privileges();
3034
perror_plus("Failed to raise privileges");
3037
/* Run network hooks */
3038
run_network_hooks("stop", interfaces_hooks != NULL ?
3039
interfaces_hooks : "", delay);
3041
/* Take down the network interfaces which were brought up */
3043
char *interface = NULL;
3044
while((interface = argz_next(interfaces_to_take_down,
3045
interfaces_to_take_down_size,
3047
ret = take_down_interface(interface);
3050
perror_plus("Failed to take down interface");
3053
if(debug and (interfaces_to_take_down == NULL)){
3054
fprintf_plus(stderr, "No interfaces needed to be taken"
3060
ret = lower_privileges_permanently();
3063
perror_plus("Failed to lower privileges permanently");
3067
free(interfaces_to_take_down);
3068
free(interfaces_hooks);
3070
void clean_dir_at(int base, const char * const dirname,
3072
struct dirent **direntries = NULL;
3074
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3080
perror_plus("open");
3083
int numentries = scandirat(dir_fd, ".", &direntries,
3084
notdotentries, alphasort);
3085
if(numentries >= 0){
3086
for(int i = 0; i < numentries; i++){
3088
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3089
dirname, direntries[i]->d_name);
3091
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3093
if(errno == EISDIR){
3094
dret = unlinkat(dir_fd, direntries[i]->d_name,
3097
if((dret == -1) and (errno == ENOTEMPTY)
3098
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3099
== 0) and (level == 0)){
3100
/* Recurse only in this special case */
3101
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3104
if((dret == -1) and (errno != ENOENT)){
3105
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3106
direntries[i]->d_name, strerror(errno));
3109
free(direntries[i]);
3112
/* need to clean even if 0 because man page doesn't specify */
3114
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3115
if(dret == -1 and errno != ENOENT){
3116
perror_plus("rmdir");
3119
perror_plus("scandirat");
3124
/* Removes the GPGME temp directory and all files inside */
3125
if(tempdir != NULL){
3126
clean_dir_at(-1, tempdir, 0);
1732
/* Take down the network interface */
1733
if(take_down_interface){
1734
/* Re-raise priviliges */
1741
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1743
perror("ioctl SIOCGIFFLAGS");
1744
} else if(network.ifr_flags & IFF_UP) {
1745
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1746
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1748
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1751
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1755
/* Lower privileges permanently */
1764
/* Removes the temp directory used by GPGME */
1765
if(tempdir_created){
1767
struct dirent *direntry;
1768
d = opendir(tempdir);
1770
if(errno != ENOENT){
1775
direntry = readdir(d);
1776
if(direntry == NULL){
1779
/* Skip "." and ".." */
1780
if(direntry->d_name[0] == '.'
1781
and (direntry->d_name[1] == '\0'
1782
or (direntry->d_name[1] == '.'
1783
and direntry->d_name[2] == '\0'))){
1786
char *fullname = NULL;
1787
ret = asprintf(&fullname, "%s/%s", tempdir,
1793
ret = remove(fullname);
1795
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1802
ret = rmdir(tempdir);
1803
if(ret == -1 and errno != ENOENT){