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 © 2008-2012 Teddy Hogeborn
13
* Copyright © 2008-2012 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
29
* Contact the authors at <mandos@recompile.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(),
43
stdout, ferror(), remove() */
45
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_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,
58
56
#include <sys/stat.h> /* open(), S_ISREG */
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,
64
#include <errno.h> /* perror(), errno,
72
65
program_invocation_short_name */
73
66
#include <time.h> /* nanosleep(), time(), sleep() */
74
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
241
224
if(new_server->ip == NULL){
242
225
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
228
/* Special case of first server */
261
if(*current_server == NULL){
229
if (mc.current_server == NULL){
262
230
new_server->next = new_server;
263
231
new_server->prev = new_server;
264
*current_server = new_server;
232
mc.current_server = new_server;
233
/* Place the new server last in the list */
266
/* Place the new server last in the list */
267
new_server->next = *current_server;
268
new_server->prev = (*current_server)->prev;
235
new_server->next = mc.current_server;
236
new_server->prev = mc.current_server->prev;
269
237
new_server->prev->next = new_server;
270
(*current_server)->prev = new_server;
238
mc.current_server->prev = new_server;
240
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
242
perror_plus("clock_gettime");
275
/* Set effective uid to 0, return errno */
276
__attribute__((warn_unused_result))
277
int raise_privileges(void){
278
int old_errno = errno;
280
if(seteuid(0) == -1){
287
/* Set effective and real user ID to 0. Return errno. */
288
__attribute__((warn_unused_result))
289
int raise_privileges_permanently(void){
290
int old_errno = errno;
291
int ret = raise_privileges();
303
/* Set effective user ID to unprivileged saved user ID */
304
__attribute__((warn_unused_result))
305
int lower_privileges(void){
306
int old_errno = errno;
308
if(seteuid(uid) == -1){
315
/* Lower privileges permanently */
316
__attribute__((warn_unused_result))
317
int lower_privileges_permanently(void){
318
int old_errno = errno;
320
if(setuid(uid) == -1){
328
249
* Initialize GPGME.
330
__attribute__((nonnull, warn_unused_result))
331
static bool init_gpgme(const char * const seckey,
332
const char * const pubkey,
333
const char * const tempdir,
251
static bool init_gpgme(const char *seckey, const char *pubkey,
252
const char *tempdir){
335
253
gpgme_error_t rc;
336
254
gpgme_engine_info_t engine_info;
339
257
* Helper function to insert pub and seckey to the engine keyring.
341
bool import_key(const char * const filename){
259
bool import_key(const char *filename){
344
262
gpgme_data_t pgp_data;
409
rc = gpgme_op_import(mc->ctx, pgp_data);
277
rc = gpgme_op_import(mc.ctx, pgp_data);
410
278
if(rc != GPG_ERR_NO_ERROR){
411
279
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
412
280
gpgme_strsource(rc), gpgme_strerror(rc));
416
gpgme_import_result_t import_result
417
= gpgme_op_import_result(mc->ctx);
418
if((import_result->imported < 1
419
or import_result->not_imported > 0)
420
and import_result->unchanged == 0){
421
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
423
"The total number of considered keys: %d\n",
424
import_result->considered);
426
"The number of keys without user ID: %d\n",
427
import_result->no_user_id);
429
"The total number of imported keys: %d\n",
430
import_result->imported);
431
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
432
import_result->imported_rsa);
433
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
434
import_result->unchanged);
435
fprintf_plus(stderr, "The number of new user IDs: %d\n",
436
import_result->new_user_ids);
437
fprintf_plus(stderr, "The number of new sub keys: %d\n",
438
import_result->new_sub_keys);
439
fprintf_plus(stderr, "The number of new signatures: %d\n",
440
import_result->new_signatures);
441
fprintf_plus(stderr, "The number of new revocations: %d\n",
442
import_result->new_revocations);
444
"The total number of secret keys read: %d\n",
445
import_result->secret_read);
447
"The number of imported secret keys: %d\n",
448
import_result->secret_imported);
450
"The number of unchanged secret keys: %d\n",
451
import_result->secret_unchanged);
452
fprintf_plus(stderr, "The number of keys not imported: %d\n",
453
import_result->not_imported);
454
for(gpgme_import_status_t import_status
455
= import_result->imports;
456
import_status != NULL;
457
import_status = import_status->next){
458
fprintf_plus(stderr, "Import status for key: %s\n",
460
if(import_status->result != GPG_ERR_NO_ERROR){
461
fprintf_plus(stderr, "Import result: %s: %s\n",
462
gpgme_strsource(import_status->result),
463
gpgme_strerror(import_status->result));
465
fprintf_plus(stderr, "Key status:\n");
467
import_status->status & GPGME_IMPORT_NEW
468
? "The key was new.\n"
469
: "The key was not new.\n");
471
import_status->status & GPGME_IMPORT_UID
472
? "The key contained new user IDs.\n"
473
: "The key did not contain new user IDs.\n");
475
import_status->status & GPGME_IMPORT_SIG
476
? "The key contained new signatures.\n"
477
: "The key did not contain new signatures.\n");
479
import_status->status & GPGME_IMPORT_SUBKEY
480
? "The key contained new sub keys.\n"
481
: "The key did not contain new sub keys.\n");
483
import_status->status & GPGME_IMPORT_SECRET
484
? "The key contained a secret key.\n"
485
: "The key did not contain a secret key.\n");
284
ret = (int)TEMP_FAILURE_RETRY(close(fd));
493
286
perror_plus("close");
585
378
/* Decrypt data from the cryptotext data buffer to the plaintext
587
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
380
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
588
381
if(rc != GPG_ERR_NO_ERROR){
589
382
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
590
383
gpgme_strsource(rc), gpgme_strerror(rc));
591
384
plaintext_length = -1;
593
386
gpgme_decrypt_result_t result;
594
result = gpgme_op_decrypt_result(mc->ctx);
387
result = gpgme_op_decrypt_result(mc.ctx);
595
388
if(result == NULL){
596
389
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
598
if(result->unsupported_algorithm != NULL) {
599
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
600
result->unsupported_algorithm);
602
fprintf_plus(stderr, "Wrong key usage: %s\n",
603
result->wrong_key_usage ? "Yes" : "No");
391
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
392
result->unsupported_algorithm);
393
fprintf_plus(stderr, "Wrong key usage: %u\n",
394
result->wrong_key_usage);
604
395
if(result->file_name != NULL){
605
396
fprintf_plus(stderr, "File name: %s\n", result->file_name);
608
for(gpgme_recipient_t r = result->recipients; r != NULL;
398
gpgme_recipient_t recipient;
399
recipient = result->recipients;
400
while(recipient != NULL){
610
401
fprintf_plus(stderr, "Public key algorithm: %s\n",
611
gpgme_pubkey_algo_name(r->pubkey_algo));
612
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
402
gpgme_pubkey_algo_name
403
(recipient->pubkey_algo));
404
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
613
405
fprintf_plus(stderr, "Secret key available: %s\n",
614
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
406
recipient->status == GPG_ERR_NO_SECKEY
408
recipient = recipient->next;
673
467
return plaintext_length;
676
__attribute__((warn_unused_result, const))
677
static const char *safe_string(const char *str){
683
__attribute__((warn_unused_result))
684
static const char *safer_gnutls_strerror(int value){
470
static const char * safer_gnutls_strerror(int value){
685
471
const char *ret = gnutls_strerror(value);
686
return safe_string(ret);
689
477
/* GnuTLS log function callback */
690
__attribute__((nonnull))
691
478
static void debuggnutls(__attribute__((unused)) int level,
692
479
const char* string){
693
480
fprintf_plus(stderr, "GnuTLS: %s", string);
696
__attribute__((nonnull(1, 2, 4), warn_unused_result))
697
483
static int init_gnutls_global(const char *pubkeyfilename,
698
const char *seckeyfilename,
699
const char *dhparamsfilename,
484
const char *seckeyfilename){
705
488
fprintf_plus(stderr, "Initializing GnuTLS\n");
491
ret = gnutls_global_init();
492
if(ret != GNUTLS_E_SUCCESS){
493
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
494
safer_gnutls_strerror(ret));
709
499
/* "Use a log level over 10 to enable all debugging options."
710
500
* - GnuTLS manual
743
534
/* GnuTLS server initialization */
744
ret = gnutls_dh_params_init(&mc->dh_params);
535
ret = gnutls_dh_params_init(&mc.dh_params);
745
536
if(ret != GNUTLS_E_SUCCESS){
746
537
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
747
538
" initialization: %s\n",
748
539
safer_gnutls_strerror(ret));
751
/* If a Diffie-Hellman parameters file was given, try to use it */
752
if(dhparamsfilename != NULL){
753
gnutls_datum_t params = { .data = NULL, .size = 0 };
755
int dhpfile = open(dhparamsfilename, O_RDONLY);
758
dhparamsfilename = NULL;
761
size_t params_capacity = 0;
763
params_capacity = incbuffer((char **)¶ms.data,
765
(size_t)params_capacity);
766
if(params_capacity == 0){
767
perror_plus("incbuffer");
770
dhparamsfilename = NULL;
773
ssize_t bytes_read = read(dhpfile,
774
params.data + params.size,
780
/* check bytes_read for failure */
785
dhparamsfilename = NULL;
788
params.size += (unsigned int)bytes_read;
790
ret = close(dhpfile);
792
perror_plus("close");
794
if(params.data == NULL){
795
dhparamsfilename = NULL;
797
if(dhparamsfilename == NULL){
800
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
801
GNUTLS_X509_FMT_PEM);
802
if(ret != GNUTLS_E_SUCCESS){
803
fprintf_plus(stderr, "Failed to parse DH parameters in file"
804
" \"%s\": %s\n", dhparamsfilename,
805
safer_gnutls_strerror(ret));
806
dhparamsfilename = NULL;
811
if(dhparamsfilename == NULL){
812
if(mc->dh_bits == 0){
813
/* Find out the optimal number of DH bits */
814
/* Try to read the private key file */
815
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
817
int secfile = open(seckeyfilename, O_RDONLY);
822
size_t buffer_capacity = 0;
824
buffer_capacity = incbuffer((char **)&buffer.data,
826
(size_t)buffer_capacity);
827
if(buffer_capacity == 0){
828
perror_plus("incbuffer");
833
ssize_t bytes_read = read(secfile,
834
buffer.data + buffer.size,
840
/* check bytes_read for failure */
847
buffer.size += (unsigned int)bytes_read;
851
/* If successful, use buffer to parse private key */
852
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
853
if(buffer.data != NULL){
855
gnutls_openpgp_privkey_t privkey = NULL;
856
ret = gnutls_openpgp_privkey_init(&privkey);
857
if(ret != GNUTLS_E_SUCCESS){
858
fprintf_plus(stderr, "Error initializing OpenPGP key"
860
safer_gnutls_strerror(ret));
864
ret = gnutls_openpgp_privkey_import
865
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
866
if(ret != GNUTLS_E_SUCCESS){
867
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
868
safer_gnutls_strerror(ret));
874
/* Use private key to suggest an appropriate
876
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
877
gnutls_openpgp_privkey_deinit(privkey);
879
fprintf_plus(stderr, "This OpenPGP key implies using"
880
" a GnuTLS security parameter \"%s\".\n",
881
safe_string(gnutls_sec_param_get_name
887
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
888
/* Err on the side of caution */
889
sec_param = GNUTLS_SEC_PARAM_ULTRA;
891
fprintf_plus(stderr, "Falling back to security parameter"
893
safe_string(gnutls_sec_param_get_name
898
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
902
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
903
" implies %u DH bits; using that.\n",
904
safe_string(gnutls_sec_param_get_name
909
fprintf_plus(stderr, "Failed to get implied number of DH"
910
" bits for security parameter \"%s\"): %s\n",
911
safe_string(gnutls_sec_param_get_name
913
safer_gnutls_strerror(ret));
917
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
920
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
921
if(ret != GNUTLS_E_SUCCESS){
922
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
923
" bits): %s\n", mc->dh_bits,
924
safer_gnutls_strerror(ret));
928
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
542
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
543
if(ret != GNUTLS_E_SUCCESS){
544
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
545
safer_gnutls_strerror(ret));
549
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
934
gnutls_certificate_free_credentials(mc->cred);
935
gnutls_dh_params_deinit(mc->dh_params);
555
gnutls_certificate_free_credentials(mc.cred);
556
gnutls_global_deinit();
557
gnutls_dh_params_deinit(mc.dh_params);
939
__attribute__((nonnull, warn_unused_result))
940
static int init_gnutls_session(gnutls_session_t *session,
561
static int init_gnutls_session(gnutls_session_t *session){
943
563
/* GnuTLS session creation */
996
618
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
997
619
__attribute__((unused)) const char *txt){}
999
/* Helper function to add_local_route() and delete_local_route() */
1000
__attribute__((nonnull, warn_unused_result))
1001
static bool add_delete_local_route(const bool add,
1002
const char *address,
1003
AvahiIfIndex if_index){
1005
char helper[] = "mandos-client-iprouteadddel";
1006
char add_arg[] = "add";
1007
char delete_arg[] = "delete";
1008
char debug_flag[] = "--debug";
1009
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1010
if(pluginhelperdir == NULL){
1012
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
1013
" variable not set; cannot run helper\n");
1018
char interface[IF_NAMESIZE];
1019
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1020
perror_plus("if_indextoname");
1024
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1026
perror_plus("open(\"/dev/null\", O_RDONLY)");
1032
/* Raise privileges */
1033
errno = raise_privileges_permanently();
1035
perror_plus("Failed to raise privileges");
1036
/* _exit(EX_NOPERM); */
1042
perror_plus("setgid");
1045
/* Reset supplementary groups */
1047
ret = setgroups(0, NULL);
1049
perror_plus("setgroups");
1053
ret = dup2(devnull, STDIN_FILENO);
1055
perror_plus("dup2(devnull, STDIN_FILENO)");
1058
ret = close(devnull);
1060
perror_plus("close");
1063
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1065
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1068
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1073
if(helperdir_fd == -1){
1074
perror_plus("open");
1075
_exit(EX_UNAVAILABLE);
1077
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1079
if(helper_fd == -1){
1080
perror_plus("openat");
1081
close(helperdir_fd);
1082
_exit(EX_UNAVAILABLE);
1084
close(helperdir_fd);
1086
#pragma GCC diagnostic push
1087
#pragma GCC diagnostic ignored "-Wcast-qual"
1089
if(fexecve(helper_fd, (char *const [])
1090
{ helper, add ? add_arg : delete_arg, (char *)address,
1091
interface, debug ? debug_flag : NULL, NULL },
1094
#pragma GCC diagnostic pop
1096
perror_plus("fexecve");
1097
_exit(EXIT_FAILURE);
1101
perror_plus("fork");
1108
pret = waitpid(pid, &status, 0);
1109
if(pret == -1 and errno == EINTR and quit_now){
1110
int errno_raising = 0;
1111
if((errno = raise_privileges()) != 0){
1112
errno_raising = errno;
1113
perror_plus("Failed to raise privileges in order to"
1114
" kill helper program");
1116
if(kill(pid, SIGTERM) == -1){
1117
perror_plus("kill");
1119
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1120
perror_plus("Failed to lower privileges after killing"
1125
} while(pret == -1 and errno == EINTR);
1127
perror_plus("waitpid");
1130
if(WIFEXITED(status)){
1131
if(WEXITSTATUS(status) != 0){
1132
fprintf_plus(stderr, "Error: iprouteadddel exited"
1133
" with status %d\n", WEXITSTATUS(status));
1138
if(WIFSIGNALED(status)){
1139
fprintf_plus(stderr, "Error: iprouteadddel died by"
1140
" signal %d\n", WTERMSIG(status));
1143
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1147
__attribute__((nonnull, warn_unused_result))
1148
static bool add_local_route(const char *address,
1149
AvahiIfIndex if_index){
1151
fprintf_plus(stderr, "Adding route to %s\n", address);
1153
return add_delete_local_route(true, address, if_index);
1156
__attribute__((nonnull, warn_unused_result))
1157
static bool delete_local_route(const char *address,
1158
AvahiIfIndex if_index){
1160
fprintf_plus(stderr, "Removing route to %s\n", address);
1162
return add_delete_local_route(false, address, if_index);
1165
621
/* Called when a Mandos server is found */
1166
__attribute__((nonnull, warn_unused_result))
1167
622
static int start_mandos_communication(const char *ip, in_port_t port,
1168
623
AvahiIfIndex if_index,
1169
int af, mandos_context *mc){
1170
625
int ret, tcp_sd = -1;
1172
struct sockaddr_storage to;
628
struct sockaddr_in in;
629
struct sockaddr_in6 in6;
1173
631
char *buffer = NULL;
1174
632
char *decrypted_buffer = NULL;
1175
633
size_t buffer_length = 0;
1315
741
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1316
742
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1318
ret = getnameinfo((struct sockaddr *)&to,
1319
sizeof(struct sockaddr_in6),
1320
addrstr, sizeof(addrstr), NULL, 0,
1323
ret = getnameinfo((struct sockaddr *)&to,
1324
sizeof(struct sockaddr_in),
1325
addrstr, sizeof(addrstr), NULL, 0,
1328
if(ret == EAI_SYSTEM){
1329
perror_plus("getnameinfo");
1330
} else if(ret != 0) {
1331
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1332
} else if(strcmp(addrstr, ip) != 0){
1333
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1344
ret = connect(tcp_sd, (struct sockaddr *)&to,
1345
sizeof(struct sockaddr_in6));
1347
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1348
sizeof(struct sockaddr_in));
1351
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1352
and if_index != AVAHI_IF_UNSPEC
1353
and connect_to == NULL
1354
and not route_added and
1355
((af == AF_INET6 and not
1356
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1358
or (af == AF_INET and
1359
/* Not a a IPv4LL address */
1360
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1361
& 0xFFFF0000L) != 0xA9FE0000L))){
1362
/* Work around Avahi bug - Avahi does not announce link-local
1363
addresses if it has a global address, so local hosts with
1364
*only* a link-local address (e.g. Mandos clients) cannot
1365
connect to a Mandos server announced by Avahi on a server
1366
host with a global address. Work around this by retrying
1367
with an explicit route added with the server's address.
1369
Avahi bug reference:
1370
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1371
https://bugs.debian.org/587961
1374
fprintf_plus(stderr, "Mandos server unreachable, trying"
1378
route_added = add_local_route(ip, if_index);
1384
if(errno != ECONNREFUSED or debug){
1386
perror_plus("connect");
745
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
748
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
752
perror_plus("inet_ntop");
754
if(strcmp(addrstr, ip) != 0){
755
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
766
ret = connect(tcp_sd, &to.in6, sizeof(to));
768
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
771
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
773
perror_plus("connect");
1399
784
const char *out = mandos_protocol_version;
2033
1381
ret = avahi_simple_poll_iterate(s, (int)block_time);
2036
if(ret > 0 or errno != EINTR){
1384
if (ret > 0 or errno != EINTR){
2037
1385
return (ret != 1) ? ret : 0;
2043
__attribute__((nonnull))
2044
void run_network_hooks(const char *mode, const char *interface,
1391
/* Set effective uid to 0, return errno */
1392
error_t raise_privileges(void){
1393
error_t old_errno = errno;
1394
error_t ret_errno = 0;
1395
if(seteuid(0) == -1){
1397
perror_plus("seteuid");
1403
/* Set effective and real user ID to 0. Return errno. */
1404
error_t raise_privileges_permanently(void){
1405
error_t old_errno = errno;
1406
error_t ret_errno = raise_privileges();
1411
if(setuid(0) == -1){
1413
perror_plus("seteuid");
1419
/* Set effective user ID to unprivileged saved user ID */
1420
error_t lower_privileges(void){
1421
error_t old_errno = errno;
1422
error_t ret_errno = 0;
1423
if(seteuid(uid) == -1){
1425
perror_plus("seteuid");
1431
/* Lower privileges permanently */
1432
error_t lower_privileges_permanently(void){
1433
error_t old_errno = errno;
1434
error_t ret_errno = 0;
1435
if(setuid(uid) == -1){
1437
perror_plus("setuid");
1443
bool run_network_hooks(const char *mode, const char *interface,
2045
1444
const float delay){
2046
struct dirent **direntries = NULL;
2047
if(hookdir_fd == -1){
2048
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2050
if(hookdir_fd == -1){
2051
if(errno == ENOENT){
2053
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2054
" found\n", hookdir);
2057
perror_plus("open");
2062
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2064
perror_plus("open(\"/dev/null\", O_RDONLY)");
2067
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2068
runnable_hook, alphasort);
1445
struct dirent **direntries;
1446
struct dirent *direntry;
1448
int numhooks = scandir(hookdir, &direntries, runnable_hook,
2069
1450
if(numhooks == -1){
2070
perror_plus("scandir");
2074
struct dirent *direntry;
2076
for(int i = 0; i < numhooks; i++){
2077
direntry = direntries[i];
2079
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1451
if(errno == ENOENT){
1453
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1454
" found\n", hookdir);
1457
perror_plus("scandir");
2082
pid_t hook_pid = fork();
2085
/* Raise privileges */
2086
errno = raise_privileges_permanently();
2088
perror_plus("Failed to raise privileges");
2095
perror_plus("setgid");
2098
/* Reset supplementary groups */
2100
ret = setgroups(0, NULL);
2102
perror_plus("setgroups");
2105
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2107
perror_plus("setenv");
2110
ret = setenv("DEVICE", interface, 1);
2112
perror_plus("setenv");
2115
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2117
perror_plus("setenv");
2120
ret = setenv("MODE", mode, 1);
2122
perror_plus("setenv");
2126
ret = asprintf(&delaystring, "%f", (double)delay);
1460
int devnull = open("/dev/null", O_RDONLY);
1461
for(int i = 0; i < numhooks; i++){
1462
direntry = direntries[i];
1463
char *fullname = NULL;
1464
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
2128
1466
perror_plus("asprintf");
2131
ret = setenv("DELAY", delaystring, 1);
1470
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1473
pid_t hook_pid = fork();
1476
/* Raise privileges */
1477
raise_privileges_permanently();
1482
perror_plus("setgid");
1484
/* Reset supplementary groups */
1486
ret = setgroups(0, NULL);
1488
perror_plus("setgroups");
1490
dup2(devnull, STDIN_FILENO);
1492
dup2(STDERR_FILENO, STDOUT_FILENO);
1493
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1495
perror_plus("setenv");
1498
ret = setenv("DEVICE", interface, 1);
1500
perror_plus("setenv");
1503
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1505
perror_plus("setenv");
1508
ret = setenv("MODE", mode, 1);
1510
perror_plus("setenv");
1514
ret = asprintf(&delaystring, "%f", delay);
1516
perror_plus("asprintf");
1519
ret = setenv("DELAY", delaystring, 1);
1522
perror_plus("setenv");
2133
1525
free(delaystring);
2134
perror_plus("setenv");
2138
if(connect_to != NULL){
2139
ret = setenv("CONNECT", connect_to, 1);
2141
perror_plus("setenv");
2145
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2149
perror_plus("openat");
2150
_exit(EXIT_FAILURE);
2152
if(close(hookdir_fd) == -1){
2153
perror_plus("close");
2154
_exit(EXIT_FAILURE);
2156
ret = dup2(devnull, STDIN_FILENO);
2158
perror_plus("dup2(devnull, STDIN_FILENO)");
2161
ret = close(devnull);
2163
perror_plus("close");
2166
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2168
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2171
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2173
perror_plus("fexecve");
2174
_exit(EXIT_FAILURE);
2178
perror_plus("fork");
2183
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2184
perror_plus("waitpid");
2188
if(WIFEXITED(status)){
2189
if(WEXITSTATUS(status) != 0){
2190
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2191
" with status %d\n", direntry->d_name,
2192
WEXITSTATUS(status));
2196
} else if(WIFSIGNALED(status)){
2197
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2198
" signal %d\n", direntry->d_name,
1526
if(connect_to != NULL){
1527
ret = setenv("CONNECT", connect_to, 1);
1529
perror_plus("setenv");
1533
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1534
perror_plus("execl");
1535
_exit(EXIT_FAILURE);
2203
fprintf_plus(stderr, "Warning: network hook \"%s\""
2204
" crashed\n", direntry->d_name);
2210
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2216
if(close(hookdir_fd) == -1){
2217
perror_plus("close");
1539
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1540
perror_plus("waitpid");
1544
if(WIFEXITED(status)){
1545
if(WEXITSTATUS(status) != 0){
1546
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1547
" with status %d\n", direntry->d_name,
1548
WEXITSTATUS(status));
1552
} else if(WIFSIGNALED(status)){
1553
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1554
" signal %d\n", direntry->d_name,
1559
fprintf_plus(stderr, "Warning: network hook \"%s\""
1560
" crashed\n", direntry->d_name);
1567
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2224
__attribute__((nonnull, warn_unused_result))
2225
int bring_up_interface(const char *const interface,
2227
int old_errno = errno;
1576
error_t bring_up_interface(const char *const interface,
1579
error_t old_errno = errno;
1580
error_t ret_errno = 0;
1581
int ret, ret_setflags;
2229
1582
struct ifreq network;
2230
1583
unsigned int if_index = if_nametoindex(interface);
2231
1584
if(if_index == 0){
2428
1748
int main(int argc, char *argv[]){
2429
mandos_context mc = { .server = NULL, .dh_bits = 0,
2430
.priority = "SECURE256:!CTYPE-X.509"
2431
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2432
.current_server = NULL, .interfaces = NULL,
2433
.interfaces_size = 0 };
2434
1749
AvahiSServiceBrowser *sb = NULL;
2435
1750
error_t ret_errno;
2437
1752
intmax_t tmpmax;
2439
1754
int exitcode = EXIT_SUCCESS;
1755
char *interfaces = NULL;
1756
size_t interfaces_size = 0;
2440
1757
char *interfaces_to_take_down = NULL;
2441
1758
size_t interfaces_to_take_down_size = 0;
2442
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2443
char old_tempdir[] = "/tmp/mandosXXXXXX";
2444
char *tempdir = NULL;
1759
char tempdir[] = "/tmp/mandosXXXXXX";
1760
bool tempdir_created = false;
2445
1761
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2446
1762
const char *seckey = PATHDIR "/" SECKEY;
2447
1763
const char *pubkey = PATHDIR "/" PUBKEY;
2448
const char *dh_params_file = NULL;
2449
1764
char *interfaces_hooks = NULL;
1765
size_t interfaces_hooks_size = 0;
2451
1767
bool gnutls_initialized = false;
2452
1768
bool gpgme_initialized = false;
2691
if(dh_params_file != NULL
2692
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2693
int dhparams_fd = open(dh_params_file, O_RDONLY);
2694
if(dhparams_fd == -1){
2695
perror_plus("open");
2697
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2699
perror_plus("fstat");
2701
if(S_ISREG(st.st_mode)
2702
and st.st_uid == 0 and st.st_gid == 0){
2703
ret = fchown(dhparams_fd, uid, gid);
2705
perror_plus("fchown");
1991
TEMP_FAILURE_RETRY(close(pubkey_fd));
2713
1995
/* Lower privileges */
2714
ret = lower_privileges();
2717
perror_plus("Failed to lower privileges");
1999
perror_plus("seteuid");
2722
/* Remove invalid interface names (except "none") */
2004
/* Remove empty interface names */
2724
2006
char *interface = NULL;
2725
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2007
while((interface = argz_next(interfaces, interfaces_size,
2727
if(strcmp(interface, "none") != 0
2728
and if_nametoindex(interface) == 0){
2729
if(interface[0] != '\0'){
2009
if(if_nametoindex(interface) == 0){
2010
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2730
2011
fprintf_plus(stderr, "Not using nonexisting interface"
2731
2012
" \"%s\"\n", interface);
2733
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2014
argz_delete(&interfaces, &interfaces_size, interface);
2734
2015
interface = NULL;
2833
2119
/* If no interfaces were specified, make a list */
2834
if(mc.interfaces == NULL){
2835
struct dirent **direntries = NULL;
2120
if(interfaces == NULL){
2121
struct dirent **direntries;
2836
2122
/* Look for any good interfaces */
2837
2123
ret = scandir(sys_class_net, &direntries, good_interface,
2840
2126
/* Add all found interfaces to interfaces list */
2841
2127
for(int i = 0; i < ret; ++i){
2842
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2128
ret_errno = argz_add(&interfaces, &interfaces_size,
2843
2129
direntries[i]->d_name);
2844
2130
if(ret_errno != 0){
2846
2131
perror_plus("argz_add");
2847
free(direntries[i]);
2851
2135
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2852
2136
direntries[i]->d_name);
2854
free(direntries[i]);
2856
2139
free(direntries);
2861
2142
fprintf_plus(stderr, "Could not find a network interface\n");
2862
2143
exitcode = EXIT_FAILURE;
2867
/* Bring up interfaces which are down, and remove any "none"s */
2148
/* If we only got one interface, explicitly use only that one */
2149
if(argz_count(interfaces, interfaces_size) == 1){
2151
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2154
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2157
/* Bring up interfaces which are down */
2158
if(not (argz_count(interfaces, interfaces_size) == 1
2159
and strcmp(interfaces, "none") == 0)){
2869
2160
char *interface = NULL;
2870
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2161
while((interface = argz_next(interfaces, interfaces_size,
2872
/* If interface name is "none", stop bringing up interfaces.
2873
Also remove all instances of "none" from the list */
2874
if(strcmp(interface, "none") == 0){
2875
argz_delete(&mc.interfaces, &mc.interfaces_size,
2878
while((interface = argz_next(mc.interfaces,
2879
mc.interfaces_size, interface))){
2880
if(strcmp(interface, "none") == 0){
2881
argz_delete(&mc.interfaces, &mc.interfaces_size,
2888
2163
bool interface_was_up = interface_is_up(interface);
2889
errno = bring_up_interface(interface, delay);
2164
ret = bring_up_interface(interface, delay);
2890
2165
if(not interface_was_up){
2892
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2893
" %s\n", interface, strerror(errno));
2168
perror_plus("Failed to bring up interface");
2895
errno = argz_add(&interfaces_to_take_down,
2896
&interfaces_to_take_down_size,
2899
perror_plus("argz_add");
2170
ret_errno = argz_add(&interfaces_to_take_down,
2171
&interfaces_to_take_down_size,
2178
interfaces_size = 0;
2904
2179
if(debug and (interfaces_to_take_down == NULL)){
2905
2180
fprintf_plus(stderr, "No interfaces were brought up\n");
2909
/* If we only got one interface, explicitly use only that one */
2910
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2912
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2915
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2922
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2188
ret = init_gnutls_global(pubkey, seckey);
2924
2190
fprintf_plus(stderr, "init_gnutls_global failed\n");
2925
2191
exitcode = EX_UNAVAILABLE;
3133
2382
mc.current_server->prev->next = NULL;
3134
2383
while(mc.current_server != NULL){
3135
2384
server *next = mc.current_server->next;
3137
#pragma GCC diagnostic push
3138
#pragma GCC diagnostic ignored "-Wcast-qual"
3140
free((char *)(mc.current_server->ip));
3142
#pragma GCC diagnostic pop
3144
2385
free(mc.current_server);
3145
2386
mc.current_server = next;
3149
/* Re-raise privileges */
2390
/* Re-raise priviliges */
3151
ret = raise_privileges();
3154
perror_plus("Failed to raise privileges");
3157
/* Run network hooks */
3158
run_network_hooks("stop", interfaces_hooks != NULL ?
3159
interfaces_hooks : "", delay);
3161
/* Take down the network interfaces which were brought up */
3163
char *interface = NULL;
3164
while((interface = argz_next(interfaces_to_take_down,
3165
interfaces_to_take_down_size,
3167
ret = take_down_interface(interface);
3170
perror_plus("Failed to take down interface");
3173
if(debug and (interfaces_to_take_down == NULL)){
3174
fprintf_plus(stderr, "No interfaces needed to be taken"
3180
ret = lower_privileges_permanently();
3183
perror_plus("Failed to lower privileges permanently");
2394
/* Run network hooks */
2395
run_network_hooks("stop", interfaces_hooks != NULL ?
2396
interfaces_hooks : "", delay);
2398
/* Take down the network interfaces which were brought up */
2400
char *interface = NULL;
2401
while((interface=argz_next(interfaces_to_take_down,
2402
interfaces_to_take_down_size,
2404
ret_errno = take_down_interface(interface);
2407
perror_plus("Failed to take down interface");
2410
if(debug and (interfaces_to_take_down == NULL)){
2411
fprintf_plus(stderr, "No interfaces needed to be taken"
2416
lower_privileges_permanently();
3187
2419
free(interfaces_to_take_down);
3188
2420
free(interfaces_hooks);
3190
void clean_dir_at(int base, const char * const dirname,
2422
/* Removes the GPGME temp directory and all files inside */
2423
if(tempdir_created){
3192
2424
struct dirent **direntries = NULL;
3194
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3200
perror_plus("open");
3203
int numentries = scandirat(dir_fd, ".", &direntries,
3204
notdotentries, alphasort);
3205
if(numentries >= 0){
2425
struct dirent *direntry = NULL;
2426
int numentries = scandir(tempdir, &direntries, notdotentries,
2428
if (numentries > 0){
3206
2429
for(int i = 0; i < numentries; i++){
3208
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3209
dirname, direntries[i]->d_name);
3211
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3213
if(errno == EISDIR){
3214
dret = unlinkat(dir_fd, direntries[i]->d_name,
3217
if((dret == -1) and (errno == ENOTEMPTY)
3218
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3219
== 0) and (level == 0)){
3220
/* Recurse only in this special case */
3221
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3224
if((dret == -1) and (errno != ENOENT)){
3225
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3226
direntries[i]->d_name, strerror(errno));
3229
free(direntries[i]);
3232
/* need to clean even if 0 because man page doesn't specify */
3234
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3235
if(dret == -1 and errno != ENOENT){
3236
perror_plus("rmdir");
3239
perror_plus("scandirat");
3244
/* Removes the GPGME temp directory and all files inside */
3245
if(tempdir != NULL){
3246
clean_dir_at(-1, tempdir, 0);
2430
direntry = direntries[i];
2431
char *fullname = NULL;
2432
ret = asprintf(&fullname, "%s/%s", tempdir,
2435
perror_plus("asprintf");
2438
ret = remove(fullname);
2440
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2447
/* need to clean even if 0 because man page doesn't specify */
2449
if (numentries == -1){
2450
perror_plus("scandir");
2452
ret = rmdir(tempdir);
2453
if(ret == -1 and errno != ENOENT){
2454
perror_plus("rmdir");