9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008-2017 Teddy Hogeborn
13
* Copyright © 2008-2017 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
12
* Copyright © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
20
* This program is distributed in the hope that it will be useful, but
23
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
24
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25
23
* General Public License for more details.
27
25
* You should have received a copy of the GNU General Public License
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
30
* Contact the authors at <mandos@recompile.se>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
33
32
/* Needed by GPGME, specifically gpgme_data_seek() */
34
33
#ifndef _LARGEFILE_SOURCE
35
34
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
37
36
#ifndef _FILE_OFFSET_BITS
38
37
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
41
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
43
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
46
45
#include <stddef.h> /* NULL, size_t, ssize_t */
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
49
48
#include <stdbool.h> /* bool, false, true */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
53
51
#include <sys/ioctl.h> /* ioctl */
54
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
55
53
sockaddr_in6, PF_INET6,
56
54
SOCK_STREAM, uid_t, gid_t, open(),
58
#include <sys/stat.h> /* open(), S_ISREG */
56
#include <sys/stat.h> /* open() */
59
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
60
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
63
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
65
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
68
EAI_SYSTEM, ENETUNREACH,
69
EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
72
program_invocation_short_name */
73
#include <time.h> /* nanosleep(), time(), sleep() */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
74
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
75
68
SIOCSIFFLAGS, if_indextoname(),
76
69
if_nametoindex(), IF_NAMESIZE */
139
120
#define PATHDIR "/conf/conf.d/mandos"
140
121
#define SECKEY "seckey.txt"
141
122
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
144
124
bool debug = false;
145
125
static const char mandos_protocol_version[] = "1";
146
126
const char *argp_program_version = "mandos-client " VERSION;
147
const char *argp_program_bug_address = "<mandos@recompile.se>";
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;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
166
129
/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
168
132
AvahiServer *server;
169
133
gnutls_certificate_credentials_t cred;
170
134
unsigned int dh_bits;
171
135
gnutls_dh_params_t dh_params;
172
136
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
177
138
} mandos_context;
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
182
sig_atomic_t quit_now = 0;
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));
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" };
205
146
* Make additional room in "buffer" for at least BUFFER_SIZE more
206
147
* bytes. "buffer_capacity" is how much is currently allocated,
207
148
* "buffer_length" is how much is already used.
209
__attribute__((nonnull, warn_unused_result))
210
150
size_t incbuffer(char **buffer, size_t buffer_length,
211
size_t buffer_capacity){
151
size_t buffer_capacity){
212
152
if(buffer_length + BUFFER_SIZE > buffer_capacity){
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
153
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
222
157
buffer_capacity += BUFFER_SIZE;
224
159
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
163
* 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,
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
283
167
gpgme_error_t rc;
284
168
gpgme_engine_info_t engine_info;
287
172
* Helper function to insert pub and seckey to the engine keyring.
289
bool import_key(const char * const filename){
174
bool import_key(const char *filename){
292
177
gpgme_data_t pgp_data;
294
179
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
300
185
rc = gpgme_data_new_from_fd(&pgp_data, fd);
301
186
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));
187
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
307
rc = gpgme_op_import(mc->ctx, pgp_data);
192
rc = gpgme_op_import(mc.ctx, pgp_data);
308
193
if(rc != GPG_ERR_NO_ERROR){
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
194
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
199
ret = (int)TEMP_FAILURE_RETRY(close(fd));
316
perror_plus("close");
318
203
gpgme_data_release(pgp_data);
323
fprintf_plus(stderr, "Initializing GPGME\n");
208
fprintf(stderr, "Initializing GPGME\n");
327
212
gpgme_check_version(NULL);
328
213
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
329
214
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));
215
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
216
gpgme_strsource(rc), gpgme_strerror(rc));
335
/* Set GPGME home directory for the OpenPGP engine only */
220
/* Set GPGME home directory for the OpenPGP engine only */
336
221
rc = gpgme_get_engine_info(&engine_info);
337
222
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));
223
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
342
227
while(engine_info != NULL){
385
266
ssize_t plaintext_length = 0;
388
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
391
272
/* Create new GPGME data buffer from memory cryptotext */
392
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
394
275
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));
276
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
400
281
/* Create new empty GPGME data buffer for the plaintext */
401
282
rc = gpgme_data_new(&dh_plain);
402
283
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));
284
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
406
286
gpgme_data_release(dh_crypto);
410
290
/* Decrypt data from the cryptotext data buffer to the plaintext
412
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
292
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
413
293
if(rc != GPG_ERR_NO_ERROR){
414
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
415
gpgme_strsource(rc), gpgme_strerror(rc));
294
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
295
gpgme_strsource(rc), gpgme_strerror(rc));
416
296
plaintext_length = -1;
418
298
gpgme_decrypt_result_t result;
419
result = gpgme_op_decrypt_result(mc->ctx);
299
result = gpgme_op_decrypt_result(mc.ctx);
420
300
if(result == NULL){
421
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
423
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
424
result->unsupported_algorithm);
425
fprintf_plus(stderr, "Wrong key usage: %u\n",
426
result->wrong_key_usage);
303
fprintf(stderr, "Unsupported algorithm: %s\n",
304
result->unsupported_algorithm);
305
fprintf(stderr, "Wrong key usage: %u\n",
306
result->wrong_key_usage);
427
307
if(result->file_name != NULL){
428
fprintf_plus(stderr, "File name: %s\n", result->file_name);
308
fprintf(stderr, "File name: %s\n", result->file_name);
430
310
gpgme_recipient_t recipient;
431
311
recipient = result->recipients;
432
312
while(recipient != NULL){
433
fprintf_plus(stderr, "Public key algorithm: %s\n",
434
gpgme_pubkey_algo_name
435
(recipient->pubkey_algo));
436
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
437
fprintf_plus(stderr, "Secret key available: %s\n",
438
recipient->status == GPG_ERR_NO_SECKEY
313
fprintf(stderr, "Public key algorithm: %s\n",
314
gpgme_pubkey_algo_name(recipient->pubkey_algo));
315
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
316
fprintf(stderr, "Secret key available: %s\n",
317
recipient->status == GPG_ERR_NO_SECKEY
440
319
recipient = recipient->next;
542
418
/* OpenPGP credentials */
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
419
gnutls_certificate_allocate_credentials(&mc.cred);
544
420
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
546
safer_gnutls_strerror(ret));
421
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
425
safer_gnutls_strerror(ret));
426
gnutls_global_deinit();
551
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
552
" secret key %s as GnuTLS credentials\n",
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
557
436
ret = gnutls_certificate_set_openpgp_key_file
558
(mc->cred, pubkeyfilename, seckeyfilename,
437
(mc.cred, pubkeyfilename, seckeyfilename,
559
438
GNUTLS_OPENPGP_FMT_BASE64);
560
439
if(ret != GNUTLS_E_SUCCESS){
562
"Error[%d] while reading the OpenPGP key pair ('%s',"
563
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
564
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
565
safer_gnutls_strerror(ret));
441
"Error[%d] while reading the OpenPGP key pair ('%s',"
442
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
443
fprintf(stderr, "The GnuTLS error is: %s\n",
444
safer_gnutls_strerror(ret));
569
448
/* GnuTLS server initialization */
570
ret = gnutls_dh_params_init(&mc->dh_params);
571
if(ret != GNUTLS_E_SUCCESS){
572
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
573
" initialization: %s\n",
574
safer_gnutls_strerror(ret));
577
/* If a Diffie-Hellman parameters file was given, try to use it */
578
if(dhparamsfilename != NULL){
579
gnutls_datum_t params = { .data = NULL, .size = 0 };
581
int dhpfile = open(dhparamsfilename, O_RDONLY);
584
dhparamsfilename = NULL;
587
size_t params_capacity = 0;
589
params_capacity = incbuffer((char **)¶ms.data,
591
(size_t)params_capacity);
592
if(params_capacity == 0){
593
perror_plus("incbuffer");
596
dhparamsfilename = NULL;
599
ssize_t bytes_read = read(dhpfile,
600
params.data + params.size,
606
/* check bytes_read for failure */
611
dhparamsfilename = NULL;
614
params.size += (unsigned int)bytes_read;
616
if(params.data == NULL){
617
dhparamsfilename = NULL;
619
if(dhparamsfilename == NULL){
622
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
623
GNUTLS_X509_FMT_PEM);
624
if(ret != GNUTLS_E_SUCCESS){
625
fprintf_plus(stderr, "Failed to parse DH parameters in file"
626
" \"%s\": %s\n", dhparamsfilename,
627
safer_gnutls_strerror(ret));
628
dhparamsfilename = NULL;
633
if(dhparamsfilename == NULL){
634
if(mc->dh_bits == 0){
635
/* Find out the optimal number of DH bits */
636
/* Try to read the private key file */
637
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
639
int secfile = open(seckeyfilename, O_RDONLY);
644
size_t buffer_capacity = 0;
646
buffer_capacity = incbuffer((char **)&buffer.data,
648
(size_t)buffer_capacity);
649
if(buffer_capacity == 0){
650
perror_plus("incbuffer");
655
ssize_t bytes_read = read(secfile,
656
buffer.data + buffer.size,
662
/* check bytes_read for failure */
669
buffer.size += (unsigned int)bytes_read;
673
/* If successful, use buffer to parse private key */
674
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
675
if(buffer.data != NULL){
677
gnutls_openpgp_privkey_t privkey = NULL;
678
ret = gnutls_openpgp_privkey_init(&privkey);
679
if(ret != GNUTLS_E_SUCCESS){
680
fprintf_plus(stderr, "Error initializing OpenPGP key"
682
safer_gnutls_strerror(ret));
686
ret = gnutls_openpgp_privkey_import
687
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
688
if(ret != GNUTLS_E_SUCCESS){
689
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
690
safer_gnutls_strerror(ret));
696
/* Use private key to suggest an appropriate
698
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
699
gnutls_openpgp_privkey_deinit(privkey);
701
fprintf_plus(stderr, "This OpenPGP key implies using"
702
" a GnuTLS security parameter \"%s\".\n",
703
safe_string(gnutls_sec_param_get_name
709
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
710
/* Err on the side of caution */
711
sec_param = GNUTLS_SEC_PARAM_ULTRA;
713
fprintf_plus(stderr, "Falling back to security parameter"
715
safe_string(gnutls_sec_param_get_name
720
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
724
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
725
" implies %u DH bits; using that.\n",
726
safe_string(gnutls_sec_param_get_name
731
fprintf_plus(stderr, "Failed to get implied number of DH"
732
" bits for security parameter \"%s\"): %s\n",
733
safe_string(gnutls_sec_param_get_name
735
safer_gnutls_strerror(ret));
739
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
742
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
743
if(ret != GNUTLS_E_SUCCESS){
744
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
745
" bits): %s\n", mc->dh_bits,
746
safer_gnutls_strerror(ret));
750
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
449
ret = gnutls_dh_params_init(&mc.dh_params);
450
if(ret != GNUTLS_E_SUCCESS){
451
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
452
" %s\n", safer_gnutls_strerror(ret));
455
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
456
if(ret != GNUTLS_E_SUCCESS){
457
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
458
safer_gnutls_strerror(ret));
462
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
756
gnutls_certificate_free_credentials(mc->cred);
757
gnutls_dh_params_deinit(mc->dh_params);
468
gnutls_certificate_free_credentials(mc.cred);
469
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
761
__attribute__((nonnull, warn_unused_result))
762
static int init_gnutls_session(gnutls_session_t *session,
474
static int init_gnutls_session(gnutls_session_t *session){
765
476
/* GnuTLS session creation */
767
478
ret = gnutls_init(session, GNUTLS_SERVER);
771
479
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
772
480
if(ret != GNUTLS_E_SUCCESS){
774
"Error in GnuTLS session initialization: %s\n",
775
safer_gnutls_strerror(ret));
481
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
482
safer_gnutls_strerror(ret));
781
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
783
gnutls_deinit(*session);
488
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
786
489
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
787
490
if(ret != GNUTLS_E_SUCCESS){
788
fprintf_plus(stderr, "Syntax error at: %s\n", err);
789
fprintf_plus(stderr, "GnuTLS error: %s\n",
790
safer_gnutls_strerror(ret));
491
fprintf(stderr, "Syntax error at: %s\n", err);
492
fprintf(stderr, "GnuTLS error: %s\n",
493
safer_gnutls_strerror(ret));
791
494
gnutls_deinit(*session);
818
519
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
819
520
__attribute__((unused)) const char *txt){}
821
/* Set effective uid to 0, return errno */
822
__attribute__((warn_unused_result))
823
int raise_privileges(void){
824
int old_errno = errno;
826
if(seteuid(0) == -1){
833
/* Set effective and real user ID to 0. Return errno. */
834
__attribute__((warn_unused_result))
835
int raise_privileges_permanently(void){
836
int old_errno = errno;
837
int ret = raise_privileges();
849
/* Set effective user ID to unprivileged saved user ID */
850
__attribute__((warn_unused_result))
851
int lower_privileges(void){
852
int old_errno = errno;
854
if(seteuid(uid) == -1){
861
/* Lower privileges permanently */
862
__attribute__((warn_unused_result))
863
int lower_privileges_permanently(void){
864
int old_errno = errno;
866
if(setuid(uid) == -1){
873
/* Helper function to add_local_route() and delete_local_route() */
874
__attribute__((nonnull, warn_unused_result))
875
static bool add_delete_local_route(const bool add,
877
AvahiIfIndex if_index){
879
char helper[] = "mandos-client-iprouteadddel";
880
char add_arg[] = "add";
881
char delete_arg[] = "delete";
882
char debug_flag[] = "--debug";
883
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
884
if(pluginhelperdir == NULL){
886
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
887
" variable not set; cannot run helper\n");
892
char interface[IF_NAMESIZE];
893
if(if_indextoname((unsigned int)if_index, interface) == NULL){
894
perror_plus("if_indextoname");
898
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
900
perror_plus("open(\"/dev/null\", O_RDONLY)");
906
/* Raise privileges */
907
errno = raise_privileges_permanently();
909
perror_plus("Failed to raise privileges");
910
/* _exit(EX_NOPERM); */
916
perror_plus("setgid");
919
/* Reset supplementary groups */
921
ret = setgroups(0, NULL);
923
perror_plus("setgroups");
927
ret = dup2(devnull, STDIN_FILENO);
929
perror_plus("dup2(devnull, STDIN_FILENO)");
932
ret = close(devnull);
934
perror_plus("close");
937
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
939
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
942
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
947
if(helperdir_fd == -1){
949
_exit(EX_UNAVAILABLE);
951
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
954
perror_plus("openat");
956
_exit(EX_UNAVAILABLE);
960
#pragma GCC diagnostic push
961
#pragma GCC diagnostic ignored "-Wcast-qual"
963
if(fexecve(helper_fd, (char *const [])
964
{ helper, add ? add_arg : delete_arg, (char *)address,
965
interface, debug ? debug_flag : NULL, NULL },
968
#pragma GCC diagnostic pop
970
perror_plus("fexecve");
982
pret = waitpid(pid, &status, 0);
983
if(pret == -1 and errno == EINTR and quit_now){
984
int errno_raising = 0;
985
if((errno = raise_privileges()) != 0){
986
errno_raising = errno;
987
perror_plus("Failed to raise privileges in order to"
988
" kill helper program");
990
if(kill(pid, SIGTERM) == -1){
993
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
994
perror_plus("Failed to lower privileges after killing"
999
} while(pret == -1 and errno == EINTR);
1001
perror_plus("waitpid");
1004
if(WIFEXITED(status)){
1005
if(WEXITSTATUS(status) != 0){
1006
fprintf_plus(stderr, "Error: iprouteadddel exited"
1007
" with status %d\n", WEXITSTATUS(status));
1012
if(WIFSIGNALED(status)){
1013
fprintf_plus(stderr, "Error: iprouteadddel died by"
1014
" signal %d\n", WTERMSIG(status));
1017
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1021
__attribute__((nonnull, warn_unused_result))
1022
static bool add_local_route(const char *address,
1023
AvahiIfIndex if_index){
1025
fprintf_plus(stderr, "Adding route to %s\n", address);
1027
return add_delete_local_route(true, address, if_index);
1030
__attribute__((nonnull, warn_unused_result))
1031
static bool delete_local_route(const char *address,
1032
AvahiIfIndex if_index){
1034
fprintf_plus(stderr, "Removing route to %s\n", address);
1036
return add_delete_local_route(false, address, if_index);
522
sig_atomic_t quit_now = 0;
523
int signal_received = 0;
1039
525
/* Called when a Mandos server is found */
1040
__attribute__((nonnull, warn_unused_result))
1041
static int start_mandos_communication(const char *ip, in_port_t port,
526
static int start_mandos_communication(const char *ip, uint16_t port,
1042
527
AvahiIfIndex if_index,
1043
int af, mandos_context *mc){
1044
529
int ret, tcp_sd = -1;
1046
struct sockaddr_storage to;
532
struct sockaddr_in in;
533
struct sockaddr_in6 in6;
1047
535
char *buffer = NULL;
1048
char *decrypted_buffer = NULL;
536
char *decrypted_buffer;
1049
537
size_t buffer_length = 0;
1050
538
size_t buffer_capacity = 0;
1053
541
gnutls_session_t session;
1054
542
int pf; /* Protocol family */
1055
bool route_added = false;
1072
fprintf_plus(stderr, "Bad address family: %d\n", af);
556
fprintf(stderr, "Bad address family: %d\n", af);
1077
/* If the interface is specified and we have a list of interfaces */
1078
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1079
/* Check if the interface is one of the interfaces we are using */
1082
char *interface = NULL;
1083
while((interface = argz_next(mc->interfaces,
1084
mc->interfaces_size,
1086
if(if_nametoindex(interface) == (unsigned int)if_index){
1093
/* This interface does not match any in the list, so we don't
1094
connect to the server */
1096
char interface[IF_NAMESIZE];
1097
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1098
perror_plus("if_indextoname");
1100
fprintf_plus(stderr, "Skipping server on non-used interface"
1102
if_indextoname((unsigned int)if_index,
1110
ret = init_gnutls_session(&session, mc);
560
ret = init_gnutls_session(&session);
1116
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1117
PRIuMAX "\n", ip, (uintmax_t)port);
566
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1120
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
570
tcp_sd = socket(pf, SOCK_STREAM, 0);
1123
perror_plus("socket");
1125
574
goto mandos_end;
1130
578
goto mandos_end;
581
memset(&to, 0, sizeof(to));
1133
582
if(af == AF_INET6){
1134
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1135
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to6->sin6_addr);
583
to.in6.sin6_family = (sa_family_t)af;
584
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1137
585
} else { /* IPv4 */
1138
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1139
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1140
ret = inet_pton(af, ip, &to4->sin_addr);
586
to.in.sin_family = (sa_family_t)af;
587
ret = inet_pton(af, ip, &to.in.sin_addr);
1144
perror_plus("inet_pton");
1146
592
goto mandos_end;
1150
fprintf_plus(stderr, "Bad address: %s\n", ip);
595
fprintf(stderr, "Bad address: %s\n", ip);
1152
597
goto mandos_end;
1154
599
if(af == AF_INET6){
1155
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1156
if(IN6_IS_ADDR_LINKLOCAL
1157
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
600
to.in6.sin6_port = htons(port); /* Spurious warnings from
602
-Wunreachable-code */
604
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
605
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
1158
607
if(if_index == AVAHI_IF_UNSPEC){
1159
fprintf_plus(stderr, "An IPv6 link-local address is"
1160
" incomplete without a network interface\n");
608
fprintf(stderr, "An IPv6 link-local address is incomplete"
609
" without a network interface\n");
1162
611
goto mandos_end;
1164
613
/* Set the network interface number as scope */
1165
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
614
to.in6.sin6_scope_id = (uint32_t)if_index;
1168
((struct sockaddr_in *)&to)->sin_port = htons(port);
617
to.in.sin_port = htons(port); /* Spurious warnings from
619
-Wunreachable-code */
1173
623
goto mandos_end;
1177
627
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1178
628
char interface[IF_NAMESIZE];
1179
629
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1180
perror_plus("if_indextoname");
630
perror("if_indextoname");
1182
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1183
"\n", ip, interface, (uintmax_t)port);
632
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
633
ip, interface, port);
1186
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1187
ip, (uintmax_t)port);
636
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1189
639
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1190
640
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1192
ret = getnameinfo((struct sockaddr *)&to,
1193
sizeof(struct sockaddr_in6),
1194
addrstr, sizeof(addrstr), NULL, 0,
1197
ret = getnameinfo((struct sockaddr *)&to,
1198
sizeof(struct sockaddr_in),
1199
addrstr, sizeof(addrstr), NULL, 0,
1202
if(ret == EAI_SYSTEM){
1203
perror_plus("getnameinfo");
1204
} else if(ret != 0) {
1205
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1206
} else if(strcmp(addrstr, ip) != 0){
1207
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1218
ret = connect(tcp_sd, (struct sockaddr *)&to,
1219
sizeof(struct sockaddr_in6));
1221
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1222
sizeof(struct sockaddr_in));
1225
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1226
and if_index != AVAHI_IF_UNSPEC
1227
and connect_to == NULL
1228
and not route_added and
1229
((af == AF_INET6 and not
1230
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1232
or (af == AF_INET and
1233
/* Not a a IPv4LL address */
1234
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1235
& 0xFFFF0000L) != 0xA9FE0000L))){
1236
/* Work around Avahi bug - Avahi does not announce link-local
1237
addresses if it has a global address, so local hosts with
1238
*only* a link-local address (e.g. Mandos clients) cannot
1239
connect to a Mandos server announced by Avahi on a server
1240
host with a global address. Work around this by retrying
1241
with an explicit route added with the server's address.
1243
Avahi bug reference:
1244
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1245
https://bugs.debian.org/587961
1248
fprintf_plus(stderr, "Mandos server unreachable, trying"
1252
route_added = add_local_route(ip, if_index);
1258
if(errno != ECONNREFUSED or debug){
1260
perror_plus("connect");
643
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
646
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
652
if(strcmp(addrstr, ip) != 0){
653
fprintf(stderr, "Canonical address form: %s\n", addrstr);
663
ret = connect(tcp_sd, &to.in6, sizeof(to));
665
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
1273
677
const char *out = mandos_protocol_version;
1628
971
signal_received = sig;
1629
972
int old_errno = errno;
1630
/* set main loop to exit */
1631
if(simple_poll != NULL){
1632
avahi_simple_poll_quit(simple_poll);
1637
__attribute__((nonnull, warn_unused_result))
1638
bool get_flags(const char *ifname, struct ifreq *ifr){
1642
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1645
perror_plus("socket");
1649
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1650
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1651
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1655
perror_plus("ioctl SIOCGIFFLAGS");
1663
__attribute__((nonnull, warn_unused_result))
1664
bool good_flags(const char *ifname, const struct ifreq *ifr){
1666
/* Reject the loopback device */
1667
if(ifr->ifr_flags & IFF_LOOPBACK){
1669
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1674
/* Accept point-to-point devices only if connect_to is specified */
1675
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1677
fprintf_plus(stderr, "Accepting point-to-point interface"
1678
" \"%s\"\n", ifname);
1682
/* Otherwise, reject non-broadcast-capable devices */
1683
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1685
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1686
" \"%s\"\n", ifname);
1690
/* Reject non-ARP interfaces (including dummy interfaces) */
1691
if(ifr->ifr_flags & IFF_NOARP){
1693
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1699
/* Accept this device */
1701
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1707
* This function determines if a directory entry in /sys/class/net
1708
* corresponds to an acceptable network device.
1709
* (This function is passed to scandir(3) as a filter function.)
1711
__attribute__((nonnull, warn_unused_result))
1712
int good_interface(const struct dirent *if_entry){
1713
if(if_entry->d_name[0] == '.'){
1718
if(not get_flags(if_entry->d_name, &ifr)){
1720
fprintf_plus(stderr, "Failed to get flags for interface "
1721
"\"%s\"\n", if_entry->d_name);
1726
if(not good_flags(if_entry->d_name, &ifr)){
1733
* This function determines if a network interface is up.
1735
__attribute__((nonnull, warn_unused_result))
1736
bool interface_is_up(const char *interface){
1738
if(not get_flags(interface, &ifr)){
1740
fprintf_plus(stderr, "Failed to get flags for interface "
1741
"\"%s\"\n", interface);
1746
return (bool)(ifr.ifr_flags & IFF_UP);
1750
* This function determines if a network interface is running
1752
__attribute__((nonnull, warn_unused_result))
1753
bool interface_is_running(const char *interface){
1755
if(not get_flags(interface, &ifr)){
1757
fprintf_plus(stderr, "Failed to get flags for interface "
1758
"\"%s\"\n", interface);
1763
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1766
__attribute__((nonnull, pure, warn_unused_result))
1767
int notdotentries(const struct dirent *direntry){
1768
/* Skip "." and ".." */
1769
if(direntry->d_name[0] == '.'
1770
and (direntry->d_name[1] == '\0'
1771
or (direntry->d_name[1] == '.'
1772
and direntry->d_name[2] == '\0'))){
1778
/* Is this directory entry a runnable program? */
1779
__attribute__((nonnull, warn_unused_result))
1780
int runnable_hook(const struct dirent *direntry){
1785
if((direntry->d_name)[0] == '\0'){
1790
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1791
"abcdefghijklmnopqrstuvwxyz"
1794
if((direntry->d_name)[sret] != '\0'){
1795
/* Contains non-allowed characters */
1797
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1803
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1806
perror_plus("Could not stat hook");
1810
if(not (S_ISREG(st.st_mode))){
1811
/* Not a regular file */
1813
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1818
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1819
/* Not executable */
1821
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1827
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1833
__attribute__((nonnull, warn_unused_result))
1834
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1835
mandos_context *mc){
1837
struct timespec now;
1838
struct timespec waited_time;
1839
intmax_t block_time;
1842
if(mc->current_server == NULL){
1844
fprintf_plus(stderr, "Wait until first server is found."
1847
ret = avahi_simple_poll_iterate(s, -1);
1850
fprintf_plus(stderr, "Check current_server if we should run"
1853
/* the current time */
1854
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1856
perror_plus("clock_gettime");
1859
/* Calculating in ms how long time between now and server
1860
who we visted longest time ago. Now - last seen. */
1861
waited_time.tv_sec = (now.tv_sec
1862
- mc->current_server->last_seen.tv_sec);
1863
waited_time.tv_nsec = (now.tv_nsec
1864
- mc->current_server->last_seen.tv_nsec);
1865
/* total time is 10s/10,000ms.
1866
Converting to s from ms by dividing by 1,000,
1867
and ns to ms by dividing by 1,000,000. */
1868
block_time = ((retry_interval
1869
- ((intmax_t)waited_time.tv_sec * 1000))
1870
- ((intmax_t)waited_time.tv_nsec / 1000000));
1873
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1877
if(block_time <= 0){
1878
ret = start_mandos_communication(mc->current_server->ip,
1879
mc->current_server->port,
1880
mc->current_server->if_index,
1881
mc->current_server->af, mc);
1883
avahi_simple_poll_quit(s);
1886
ret = clock_gettime(CLOCK_MONOTONIC,
1887
&mc->current_server->last_seen);
1889
perror_plus("clock_gettime");
1892
mc->current_server = mc->current_server->next;
1893
block_time = 0; /* Call avahi to find new Mandos
1894
servers, but don't block */
1897
ret = avahi_simple_poll_iterate(s, (int)block_time);
1900
if(ret > 0 or errno != EINTR){
1901
return (ret != 1) ? ret : 0;
1907
__attribute__((nonnull))
1908
void run_network_hooks(const char *mode, const char *interface,
1910
struct dirent **direntries = NULL;
1911
if(hookdir_fd == -1){
1912
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1914
if(hookdir_fd == -1){
1915
if(errno == ENOENT){
1917
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1918
" found\n", hookdir);
1921
perror_plus("open");
1926
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1927
runnable_hook, alphasort);
1929
perror_plus("scandir");
1932
struct dirent *direntry;
1934
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1936
perror_plus("open(\"/dev/null\", O_RDONLY)");
1939
for(int i = 0; i < numhooks; i++){
1940
direntry = direntries[i];
1942
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1945
pid_t hook_pid = fork();
1948
/* Raise privileges */
1949
errno = raise_privileges_permanently();
1951
perror_plus("Failed to raise privileges");
1958
perror_plus("setgid");
1961
/* Reset supplementary groups */
1963
ret = setgroups(0, NULL);
1965
perror_plus("setgroups");
1968
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1970
perror_plus("setenv");
1973
ret = setenv("DEVICE", interface, 1);
1975
perror_plus("setenv");
1978
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1980
perror_plus("setenv");
1983
ret = setenv("MODE", mode, 1);
1985
perror_plus("setenv");
1989
ret = asprintf(&delaystring, "%f", (double)delay);
1991
perror_plus("asprintf");
1994
ret = setenv("DELAY", delaystring, 1);
1997
perror_plus("setenv");
2001
if(connect_to != NULL){
2002
ret = setenv("CONNECT", connect_to, 1);
2004
perror_plus("setenv");
2008
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2012
perror_plus("openat");
2013
_exit(EXIT_FAILURE);
2015
if(close(hookdir_fd) == -1){
2016
perror_plus("close");
2017
_exit(EXIT_FAILURE);
2019
ret = dup2(devnull, STDIN_FILENO);
2021
perror_plus("dup2(devnull, STDIN_FILENO)");
2024
ret = close(devnull);
2026
perror_plus("close");
2029
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2031
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2034
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2036
perror_plus("fexecve");
2037
_exit(EXIT_FAILURE);
2041
perror_plus("fork");
2046
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2047
perror_plus("waitpid");
2051
if(WIFEXITED(status)){
2052
if(WEXITSTATUS(status) != 0){
2053
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2054
" with status %d\n", direntry->d_name,
2055
WEXITSTATUS(status));
2059
} else if(WIFSIGNALED(status)){
2060
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2061
" signal %d\n", direntry->d_name,
2066
fprintf_plus(stderr, "Warning: network hook \"%s\""
2067
" crashed\n", direntry->d_name);
2073
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2079
if(close(hookdir_fd) == -1){
2080
perror_plus("close");
2087
__attribute__((nonnull, warn_unused_result))
2088
int bring_up_interface(const char *const interface,
2090
int old_errno = errno;
2092
struct ifreq network;
2093
unsigned int if_index = if_nametoindex(interface);
2095
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2105
if(not interface_is_up(interface)){
2107
int ioctl_errno = 0;
2108
if(not get_flags(interface, &network)){
2110
fprintf_plus(stderr, "Failed to get flags for interface "
2111
"\"%s\"\n", interface);
2115
network.ifr_flags |= IFF_UP; /* set flag */
2117
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2120
perror_plus("socket");
2128
perror_plus("close");
2135
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2139
/* Raise privileges */
2140
ret_errno = raise_privileges();
2143
perror_plus("Failed to raise privileges");
2148
bool restore_loglevel = false;
2150
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2151
messages about the network interface to mess up the prompt */
2152
ret_linux = klogctl(8, NULL, 5);
2153
if(ret_linux == -1){
2154
perror_plus("klogctl");
2156
restore_loglevel = true;
2159
#endif /* __linux__ */
2160
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2161
ioctl_errno = errno;
2163
if(restore_loglevel){
2164
ret_linux = klogctl(7, NULL, 0);
2165
if(ret_linux == -1){
2166
perror_plus("klogctl");
2169
#endif /* __linux__ */
2171
/* If raise_privileges() succeeded above */
2173
/* Lower privileges */
2174
ret_errno = lower_privileges();
2177
perror_plus("Failed to lower privileges");
2181
/* Close the socket */
2184
perror_plus("close");
2187
if(ret_setflags == -1){
2188
errno = ioctl_errno;
2189
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2194
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2198
/* Sleep checking until interface is running.
2199
Check every 0.25s, up to total time of delay */
2200
for(int i = 0; i < delay * 4; i++){
2201
if(interface_is_running(interface)){
2204
struct timespec sleeptime = { .tv_nsec = 250000000 };
2205
ret = nanosleep(&sleeptime, NULL);
2206
if(ret == -1 and errno != EINTR){
2207
perror_plus("nanosleep");
2215
__attribute__((nonnull, warn_unused_result))
2216
int take_down_interface(const char *const interface){
2217
int old_errno = errno;
2218
struct ifreq network;
2219
unsigned int if_index = if_nametoindex(interface);
2221
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2225
if(interface_is_up(interface)){
2227
int ioctl_errno = 0;
2228
if(not get_flags(interface, &network) and debug){
2230
fprintf_plus(stderr, "Failed to get flags for interface "
2231
"\"%s\"\n", interface);
2235
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2237
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2240
perror_plus("socket");
2246
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2250
/* Raise privileges */
2251
ret_errno = raise_privileges();
2254
perror_plus("Failed to raise privileges");
2257
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2258
ioctl_errno = errno;
2260
/* If raise_privileges() succeeded above */
2262
/* Lower privileges */
2263
ret_errno = lower_privileges();
2266
perror_plus("Failed to lower privileges");
2270
/* Close the socket */
2271
int ret = close(sd);
2273
perror_plus("close");
2276
if(ret_setflags == -1){
2277
errno = ioctl_errno;
2278
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2283
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
973
if(mc.simple_poll != NULL){
974
avahi_simple_poll_quit(mc.simple_poll);
2291
979
int main(int argc, char *argv[]){
2292
mandos_context mc = { .server = NULL, .dh_bits = 0,
2293
.priority = "SECURE256:!CTYPE-X.509"
2294
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2295
.current_server = NULL, .interfaces = NULL,
2296
.interfaces_size = 0 };
2297
980
AvahiSServiceBrowser *sb = NULL;
2300
983
intmax_t tmpmax;
2302
985
int exitcode = EXIT_SUCCESS;
2303
char *interfaces_to_take_down = NULL;
2304
size_t interfaces_to_take_down_size = 0;
2305
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2306
char old_tempdir[] = "/tmp/mandosXXXXXX";
2307
char *tempdir = NULL;
986
const char *interface = "eth0";
987
struct ifreq network;
989
bool take_down_interface = false;
992
char *connect_to = NULL;
993
char tempdir[] = "/tmp/mandosXXXXXX";
994
bool tempdir_created = false;
2308
995
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2309
996
const char *seckey = PATHDIR "/" SECKEY;
2310
997
const char *pubkey = PATHDIR "/" PUBKEY;
2311
const char *dh_params_file = NULL;
2312
char *interfaces_hooks = NULL;
2314
999
bool gnutls_initialized = false;
2315
1000
bool gpgme_initialized = false;
2316
1001
float delay = 2.5f;
2317
double retry_interval = 10; /* 10s between trying a server and
2318
retrying the same server again */
2320
1003
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2321
1004
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2443
1097
delay = strtof(arg, &tmp);
2444
1098
if(errno != 0 or tmp == arg or *tmp != '\0'){
2445
argp_error(state, "Bad delay");
2447
case 132: /* --retry */
2449
retry_interval = strtod(arg, &tmp);
2450
if(errno != 0 or tmp == arg or *tmp != '\0'
2451
or (retry_interval * 1000) > INT_MAX
2452
or retry_interval < 0){
2453
argp_error(state, "Bad retry interval");
2456
case 133: /* --network-hook-dir */
2460
* These reproduce what we would get without ARGP_NO_HELP
2462
case '?': /* --help */
2463
argp_state_help(state, state->out_stream,
2464
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2465
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2466
case -3: /* --usage */
2467
argp_state_help(state, state->out_stream,
2468
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2469
case 'V': /* --version */
2470
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2471
exit(argp_err_exit_status);
1099
fprintf(stderr, "Bad delay\n");
2474
1108
return ARGP_ERR_UNKNOWN;
2479
1113
struct argp argp = { .options = options, .parser = parse_opt,
2480
1114
.args_doc = "",
2481
1115
.doc = "Mandos client -- Get and decrypt"
2482
1116
" passwords from a Mandos server" };
2483
ret_errno = argp_parse(&argp, argc, argv,
2484
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2491
perror_plus("argp_parse");
2492
exitcode = EX_OSERR;
2495
exitcode = EX_USAGE;
2501
/* Work around Debian bug #633582:
2502
<https://bugs.debian.org/633582> */
2504
/* Re-raise privileges */
2505
ret = raise_privileges();
2508
perror_plus("Failed to raise privileges");
2512
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2513
int seckey_fd = open(seckey, O_RDONLY);
2514
if(seckey_fd == -1){
2515
perror_plus("open");
2517
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2519
perror_plus("fstat");
2521
if(S_ISREG(st.st_mode)
2522
and st.st_uid == 0 and st.st_gid == 0){
2523
ret = fchown(seckey_fd, uid, gid);
2525
perror_plus("fchown");
2533
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2534
int pubkey_fd = open(pubkey, O_RDONLY);
2535
if(pubkey_fd == -1){
2536
perror_plus("open");
2538
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2540
perror_plus("fstat");
2542
if(S_ISREG(st.st_mode)
2543
and st.st_uid == 0 and st.st_gid == 0){
2544
ret = fchown(pubkey_fd, uid, gid);
2546
perror_plus("fchown");
2554
if(dh_params_file != NULL
2555
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2556
int dhparams_fd = open(dh_params_file, O_RDONLY);
2557
if(dhparams_fd == -1){
2558
perror_plus("open");
2560
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2562
perror_plus("fstat");
2564
if(S_ISREG(st.st_mode)
2565
and st.st_uid == 0 and st.st_gid == 0){
2566
ret = fchown(dhparams_fd, uid, gid);
2568
perror_plus("fchown");
2576
/* Lower privileges */
2577
ret = lower_privileges();
2580
perror_plus("Failed to lower privileges");
2585
/* Remove invalid interface names (except "none") */
2587
char *interface = NULL;
2588
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2590
if(strcmp(interface, "none") != 0
2591
and if_nametoindex(interface) == 0){
2592
if(interface[0] != '\0'){
2593
fprintf_plus(stderr, "Not using nonexisting interface"
2594
" \"%s\"\n", interface);
2596
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2602
/* Run network hooks */
2604
if(mc.interfaces != NULL){
2605
interfaces_hooks = malloc(mc.interfaces_size);
2606
if(interfaces_hooks == NULL){
2607
perror_plus("malloc");
2610
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2611
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2613
run_network_hooks("start", interfaces_hooks != NULL ?
2614
interfaces_hooks : "", delay);
1117
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1118
if(ret == ARGP_ERR_UNKNOWN){
1119
fprintf(stderr, "Unknown error while parsing arguments\n");
1120
exitcode = EXIT_FAILURE;
2656
1163
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2658
perror_plus("sigaction");
1165
perror("sigaction");
1166
return EXIT_FAILURE;
2661
1168
if(old_sigterm_action.sa_handler != SIG_IGN){
2662
1169
ret = sigaction(SIGINT, &sigterm_action, NULL);
2664
perror_plus("sigaction");
2665
exitcode = EX_OSERR;
1171
perror("sigaction");
1172
exitcode = EXIT_FAILURE;
2669
1176
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2671
perror_plus("sigaction");
1178
perror("sigaction");
1179
return EXIT_FAILURE;
2674
1181
if(old_sigterm_action.sa_handler != SIG_IGN){
2675
1182
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2677
perror_plus("sigaction");
2678
exitcode = EX_OSERR;
1184
perror("sigaction");
1185
exitcode = EXIT_FAILURE;
2682
1189
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2684
perror_plus("sigaction");
1191
perror("sigaction");
1192
return EXIT_FAILURE;
2687
1194
if(old_sigterm_action.sa_handler != SIG_IGN){
2688
1195
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2690
perror_plus("sigaction");
2691
exitcode = EX_OSERR;
1197
perror("sigaction");
1198
exitcode = EXIT_FAILURE;
2696
/* If no interfaces were specified, make a list */
2697
if(mc.interfaces == NULL){
2698
struct dirent **direntries = NULL;
2699
/* Look for any good interfaces */
2700
ret = scandir(sys_class_net, &direntries, good_interface,
2703
/* Add all found interfaces to interfaces list */
2704
for(int i = 0; i < ret; ++i){
2705
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2706
direntries[i]->d_name);
2709
perror_plus("argz_add");
2710
free(direntries[i]);
2714
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2715
direntries[i]->d_name);
2717
free(direntries[i]);
1203
/* If the interface is down, bring it up */
1204
if(interface[0] != '\0'){
1205
if_index = (AvahiIfIndex) if_nametoindex(interface);
1207
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1208
exitcode = EXIT_FAILURE;
1216
/* Re-raise priviliges */
1224
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1225
messages to mess up the prompt */
1226
ret = klogctl(8, NULL, 5);
1227
bool restore_loglevel = true;
1229
restore_loglevel = false;
1232
#endif /* __linux__ */
1234
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1237
exitcode = EXIT_FAILURE;
1239
if(restore_loglevel){
1240
ret = klogctl(7, NULL, 0);
1245
#endif /* __linux__ */
1246
/* Lower privileges */
1254
strcpy(network.ifr_name, interface);
1255
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1257
perror("ioctl SIOCGIFFLAGS");
1259
if(restore_loglevel){
1260
ret = klogctl(7, NULL, 0);
1265
#endif /* __linux__ */
1266
exitcode = EXIT_FAILURE;
1267
/* Lower privileges */
1275
if((network.ifr_flags & IFF_UP) == 0){
1276
network.ifr_flags |= IFF_UP;
1277
take_down_interface = true;
1278
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1280
take_down_interface = false;
1281
perror("ioctl SIOCSIFFLAGS");
1282
exitcode = EXIT_FAILURE;
1284
if(restore_loglevel){
1285
ret = klogctl(7, NULL, 0);
1290
#endif /* __linux__ */
1291
/* Lower privileges */
1300
/* sleep checking until interface is running */
1301
for(int i=0; i < delay * 4; i++){
1302
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1304
perror("ioctl SIOCGIFFLAGS");
1305
} else if(network.ifr_flags & IFF_RUNNING){
1308
struct timespec sleeptime = { .tv_nsec = 250000000 };
1309
ret = nanosleep(&sleeptime, NULL);
1310
if(ret == -1 and errno != EINTR){
1311
perror("nanosleep");
1314
if(not take_down_interface){
1315
/* We won't need the socket anymore */
1316
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1322
if(restore_loglevel){
1323
/* Restores kernel loglevel to default */
1324
ret = klogctl(7, NULL, 0);
1329
#endif /* __linux__ */
1330
/* Lower privileges */
1332
if(take_down_interface){
1333
/* Lower privileges */
2724
fprintf_plus(stderr, "Could not find a network interface\n");
2725
exitcode = EXIT_FAILURE;
2730
/* Bring up interfaces which are down, and remove any "none"s */
2732
char *interface = NULL;
2733
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2735
/* If interface name is "none", stop bringing up interfaces.
2736
Also remove all instances of "none" from the list */
2737
if(strcmp(interface, "none") == 0){
2738
argz_delete(&mc.interfaces, &mc.interfaces_size,
2741
while((interface = argz_next(mc.interfaces,
2742
mc.interfaces_size, interface))){
2743
if(strcmp(interface, "none") == 0){
2744
argz_delete(&mc.interfaces, &mc.interfaces_size,
2751
bool interface_was_up = interface_is_up(interface);
2752
errno = bring_up_interface(interface, delay);
2753
if(not interface_was_up){
2755
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2756
" %s\n", interface, strerror(errno));
2758
errno = argz_add(&interfaces_to_take_down,
2759
&interfaces_to_take_down_size,
2762
perror_plus("argz_add");
2767
if(debug and (interfaces_to_take_down == NULL)){
2768
fprintf_plus(stderr, "No interfaces were brought up\n");
2772
/* If we only got one interface, explicitly use only that one */
2773
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2775
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2778
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1339
/* Lower privileges permanently */
2785
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1351
ret = init_gnutls_global(pubkey, seckey);
2787
fprintf_plus(stderr, "init_gnutls_global failed\n");
2788
exitcode = EX_UNAVAILABLE;
1353
fprintf(stderr, "init_gnutls_global failed\n");
1354
exitcode = EXIT_FAILURE;
2791
1357
gnutls_initialized = true;
2990
1519
gpgme_release(mc.ctx);
2993
/* Cleans up the circular linked list of Mandos servers the client
2995
if(mc.current_server != NULL){
2996
mc.current_server->prev->next = NULL;
2997
while(mc.current_server != NULL){
2998
server *next = mc.current_server->next;
3000
#pragma GCC diagnostic push
3001
#pragma GCC diagnostic ignored "-Wcast-qual"
3003
free((char *)(mc.current_server->ip));
3005
#pragma GCC diagnostic pop
3007
free(mc.current_server);
3008
mc.current_server = next;
3012
/* Re-raise privileges */
3014
ret = raise_privileges();
3017
perror_plus("Failed to raise privileges");
3020
/* Run network hooks */
3021
run_network_hooks("stop", interfaces_hooks != NULL ?
3022
interfaces_hooks : "", delay);
3024
/* Take down the network interfaces which were brought up */
3026
char *interface = NULL;
3027
while((interface = argz_next(interfaces_to_take_down,
3028
interfaces_to_take_down_size,
3030
ret = take_down_interface(interface);
3033
perror_plus("Failed to take down interface");
3036
if(debug and (interfaces_to_take_down == NULL)){
3037
fprintf_plus(stderr, "No interfaces needed to be taken"
3043
ret = lower_privileges_permanently();
3046
perror_plus("Failed to lower privileges permanently");
3050
free(interfaces_to_take_down);
3051
free(interfaces_hooks);
3053
void clean_dir_at(int base, const char * const dirname,
3055
struct dirent **direntries = NULL;
3057
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3063
perror_plus("open");
3065
int numentries = scandirat(dir_fd, ".", &direntries,
3066
notdotentries, alphasort);
3067
if(numentries >= 0){
3068
for(int i = 0; i < numentries; i++){
3070
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3071
dirname, direntries[i]->d_name);
3073
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3075
if(errno == EISDIR){
3076
dret = unlinkat(dir_fd, direntries[i]->d_name,
3079
if((dret == -1) and (errno == ENOTEMPTY)
3080
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3081
== 0) and (level == 0)){
3082
/* Recurse only in this special case */
3083
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3087
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3088
direntries[i]->d_name, strerror(errno));
3091
free(direntries[i]);
3094
/* need to clean even if 0 because man page doesn't specify */
3096
if(numentries == -1){
3097
perror_plus("scandirat");
3099
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3100
if(dret == -1 and errno != ENOENT){
3101
perror_plus("rmdir");
3104
perror_plus("scandirat");
3109
/* Removes the GPGME temp directory and all files inside */
3110
if(tempdir != NULL){
3111
clean_dir_at(-1, tempdir, 0);
1522
/* Take down the network interface */
1523
if(take_down_interface){
1524
/* Re-raise priviliges */
1531
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1533
perror("ioctl SIOCGIFFLAGS");
1534
} else if(network.ifr_flags & IFF_UP) {
1535
network.ifr_flags &= ~IFF_UP; /* clear flag */
1536
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1538
perror("ioctl SIOCSIFFLAGS");
1541
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1545
/* Lower privileges permanently */
1554
/* Removes the temp directory used by GPGME */
1555
if(tempdir_created){
1557
struct dirent *direntry;
1558
d = opendir(tempdir);
1560
if(errno != ENOENT){
1565
direntry = readdir(d);
1566
if(direntry == NULL){
1569
/* Skip "." and ".." */
1570
if(direntry->d_name[0] == '.'
1571
and (direntry->d_name[1] == '\0'
1572
or (direntry->d_name[1] == '.'
1573
and direntry->d_name[2] == '\0'))){
1576
char *fullname = NULL;
1577
ret = asprintf(&fullname, "%s/%s", tempdir,
1583
ret = remove(fullname);
1585
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1592
ret = rmdir(tempdir);
1593
if(ret == -1 and errno != ENOENT){
3115
1599
sigemptyset(&old_sigterm_action.sa_mask);
3116
1600
old_sigterm_action.sa_handler = SIG_DFL;
3117
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3118
&old_sigterm_action,
1601
ret = sigaction(signal_received, &old_sigterm_action, NULL);
3121
perror_plus("sigaction");
3124
ret = raise(signal_received);
3125
} while(ret != 0 and errno == EINTR);
3127
perror_plus("raise");
3130
TEMP_FAILURE_RETRY(pause());
1603
perror("sigaction");
1605
raise(signal_received);
3133
1608
return exitcode;