9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008-2010 Teddy Hogeborn
13
* Copyright © 2008-2010 Björn Påhlsson
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
20
* This program is distributed in the hope that it will be useful, but
12
* Copyright © 2008-2020 Teddy Hogeborn
13
* Copyright © 2008-2020 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
21
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
25
* General Public License for more details.
25
27
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
* Contact the authors at <mandos@recompile.se>.
32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
33
34
#ifndef _LARGEFILE_SOURCE
34
35
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
36
37
#ifndef _FILE_OFFSET_BITS
37
38
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
40
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
46
#include <stddef.h> /* NULL, size_t, ssize_t */
46
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
48
strtof(), abort() */
48
49
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
51
53
#include <sys/ioctl.h> /* ioctl */
52
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
55
sockaddr_in6, PF_INET6,
54
56
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open() */
58
#include <sys/stat.h> /* open(), S_ISREG */
57
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
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 */
66
73
#include <time.h> /* nanosleep(), time(), sleep() */
67
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
75
SIOCSIFFLAGS, if_indextoname(),
122
145
#define PATHDIR "/conf/conf.d/mandos"
123
146
#define SECKEY "seckey.txt"
124
147
#define PUBKEY "pubkey.txt"
148
#define TLS_PRIVKEY "tls-privkey.pem"
149
#define TLS_PUBKEY "tls-pubkey.pem"
150
#define HOOKDIR "/lib/mandos/network-hooks.d"
126
152
bool debug = false;
127
153
static const char mandos_protocol_version[] = "1";
128
154
const char *argp_program_version = "mandos-client " VERSION;
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
155
const char *argp_program_bug_address = "<mandos@recompile.se>";
130
156
static const char sys_class_net[] = "/sys/class/net";
131
157
char *connect_to = NULL;
158
const char *hookdir = HOOKDIR;
163
/* Doubly linked list that need to be circularly linked when used */
164
typedef struct server{
167
AvahiIfIndex if_index;
169
struct timespec last_seen;
133
174
/* Used for passing in values through the Avahi callback functions */
135
AvahiSimplePoll *simple_poll;
136
176
AvahiServer *server;
137
177
gnutls_certificate_credentials_t cred;
138
178
unsigned int dh_bits;
139
179
gnutls_dh_params_t dh_params;
140
180
const char *priority;
182
server *current_server;
184
size_t interfaces_size;
142
185
} mandos_context;
144
/* global context so signal handler can reach it*/
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
187
/* global so signal handler can reach it*/
188
AvahiSimplePoll *simple_poll;
149
190
sig_atomic_t quit_now = 0;
150
191
int signal_received = 0;
193
/* Function to use when printing errors */
194
void perror_plus(const char *print_text){
196
fprintf(stderr, "Mandos plugin %s: ",
197
program_invocation_short_name);
202
__attribute__((format (gnu_printf, 2, 3), nonnull))
203
int fprintf_plus(FILE *stream, const char *format, ...){
205
va_start (ap, format);
207
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
208
program_invocation_short_name));
209
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
153
213
* Make additional room in "buffer" for at least BUFFER_SIZE more
154
214
* bytes. "buffer_capacity" is how much is currently allocated,
155
215
* "buffer_length" is how much is already used.
217
__attribute__((nonnull, warn_unused_result))
157
218
size_t incbuffer(char **buffer, size_t buffer_length,
158
size_t buffer_capacity){
219
size_t buffer_capacity){
159
220
if(buffer_length + BUFFER_SIZE > buffer_capacity){
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
221
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
223
int old_errno = errno;
164
230
buffer_capacity += BUFFER_SIZE;
166
232
return buffer_capacity;
235
/* Add server to set of servers to retry periodically */
236
__attribute__((nonnull, warn_unused_result))
237
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
238
int af, server **current_server){
240
server *new_server = malloc(sizeof(server));
241
if(new_server == NULL){
242
perror_plus("malloc");
245
*new_server = (server){ .ip = strdup(ip),
247
.if_index = if_index,
249
if(new_server->ip == NULL){
250
perror_plus("strdup");
254
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
256
perror_plus("clock_gettime");
258
#pragma GCC diagnostic push
259
#pragma GCC diagnostic ignored "-Wcast-qual"
261
free((char *)(new_server->ip));
263
#pragma GCC diagnostic pop
268
/* Special case of first server */
269
if(*current_server == NULL){
270
new_server->next = new_server;
271
new_server->prev = new_server;
272
*current_server = new_server;
274
/* Place the new server last in the list */
275
new_server->next = *current_server;
276
new_server->prev = (*current_server)->prev;
277
new_server->prev->next = new_server;
278
(*current_server)->prev = new_server;
283
/* Set effective uid to 0, return errno */
284
__attribute__((warn_unused_result))
285
int raise_privileges(void){
286
int old_errno = errno;
288
if(seteuid(0) == -1){
295
/* Set effective and real user ID to 0. Return errno. */
296
__attribute__((warn_unused_result))
297
int raise_privileges_permanently(void){
298
int old_errno = errno;
299
int ret = raise_privileges();
311
/* Set effective user ID to unprivileged saved user ID */
312
__attribute__((warn_unused_result))
313
int lower_privileges(void){
314
int old_errno = errno;
316
if(seteuid(uid) == -1){
323
/* Lower privileges permanently */
324
__attribute__((warn_unused_result))
325
int lower_privileges_permanently(void){
326
int old_errno = errno;
328
if(setuid(uid) == -1){
170
336
* Initialize GPGME.
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
338
__attribute__((nonnull, warn_unused_result))
339
static bool init_gpgme(const char * const seckey,
340
const char * const pubkey,
341
const char * const tempdir,
174
343
gpgme_error_t rc;
175
344
gpgme_engine_info_t engine_info;
179
347
* Helper function to insert pub and seckey to the engine keyring.
181
bool import_key(const char *filename){
349
bool import_key(const char * const filename){
184
352
gpgme_data_t pgp_data;
186
354
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
360
/* Workaround for systems without a real-time clock; see also
361
Debian bug #894495: <https://bugs.debian.org/894495> */
364
time_t currtime = time(NULL);
365
if(currtime != (time_t)-1){
367
if(gmtime_r(&currtime, &tm) == NULL) {
368
perror_plus("gmtime_r");
371
if(tm.tm_year != 70 or tm.tm_mon != 0){
375
fprintf_plus(stderr, "System clock is January 1970");
379
fprintf_plus(stderr, "System clock is invalid");
384
ret = fstat(fd, &keystat);
386
perror_plus("fstat");
389
ret = raise_privileges();
392
perror_plus("Failed to raise privileges");
397
"Setting system clock to key file mtime");
399
if(clock_settime(CLOCK_REALTIME, &keystat.st_mtim) != 0){
400
perror_plus("clock_settime");
402
ret = lower_privileges();
405
perror_plus("Failed to lower privileges");
192
409
rc = gpgme_data_new_from_fd(&pgp_data, fd);
193
410
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
411
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
412
gpgme_strsource(rc), gpgme_strerror(rc));
199
rc = gpgme_op_import(mc.ctx, pgp_data);
416
rc = gpgme_op_import(mc->ctx, pgp_data);
200
417
if(rc != GPG_ERR_NO_ERROR){
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
gpgme_strsource(rc), gpgme_strerror(rc));
418
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
419
gpgme_strsource(rc), gpgme_strerror(rc));
423
gpgme_import_result_t import_result
424
= gpgme_op_import_result(mc->ctx);
425
if((import_result->imported < 1
426
or import_result->not_imported > 0)
427
and import_result->unchanged == 0){
428
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
430
"The total number of considered keys: %d\n",
431
import_result->considered);
433
"The number of keys without user ID: %d\n",
434
import_result->no_user_id);
436
"The total number of imported keys: %d\n",
437
import_result->imported);
438
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
439
import_result->imported_rsa);
440
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
441
import_result->unchanged);
442
fprintf_plus(stderr, "The number of new user IDs: %d\n",
443
import_result->new_user_ids);
444
fprintf_plus(stderr, "The number of new sub keys: %d\n",
445
import_result->new_sub_keys);
446
fprintf_plus(stderr, "The number of new signatures: %d\n",
447
import_result->new_signatures);
448
fprintf_plus(stderr, "The number of new revocations: %d\n",
449
import_result->new_revocations);
451
"The total number of secret keys read: %d\n",
452
import_result->secret_read);
454
"The number of imported secret keys: %d\n",
455
import_result->secret_imported);
457
"The number of unchanged secret keys: %d\n",
458
import_result->secret_unchanged);
459
fprintf_plus(stderr, "The number of keys not imported: %d\n",
460
import_result->not_imported);
461
for(gpgme_import_status_t import_status
462
= import_result->imports;
463
import_status != NULL;
464
import_status = import_status->next){
465
fprintf_plus(stderr, "Import status for key: %s\n",
467
if(import_status->result != GPG_ERR_NO_ERROR){
468
fprintf_plus(stderr, "Import result: %s: %s\n",
469
gpgme_strsource(import_status->result),
470
gpgme_strerror(import_status->result));
472
fprintf_plus(stderr, "Key status:\n");
474
import_status->status & GPGME_IMPORT_NEW
475
? "The key was new.\n"
476
: "The key was not new.\n");
478
import_status->status & GPGME_IMPORT_UID
479
? "The key contained new user IDs.\n"
480
: "The key did not contain new user IDs.\n");
482
import_status->status & GPGME_IMPORT_SIG
483
? "The key contained new signatures.\n"
484
: "The key did not contain new signatures.\n");
486
import_status->status & GPGME_IMPORT_SUBKEY
487
? "The key contained new sub keys.\n"
488
: "The key did not contain new sub keys.\n");
490
import_status->status & GPGME_IMPORT_SECRET
491
? "The key contained a secret key.\n"
492
: "The key did not contain a secret key.\n");
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
500
perror_plus("close");
210
502
gpgme_data_release(pgp_data);
215
fprintf(stderr, "Initializing GPGME\n");
507
fprintf_plus(stderr, "Initializing GPGME\n");
219
511
gpgme_check_version(NULL);
220
512
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
221
513
if(rc != GPG_ERR_NO_ERROR){
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
514
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
515
gpgme_strsource(rc), gpgme_strerror(rc));
227
/* Set GPGME home directory for the OpenPGP engine only */
519
/* Set GPGME home directory for the OpenPGP engine only */
228
520
rc = gpgme_get_engine_info(&engine_info);
229
521
if(rc != GPG_ERR_NO_ERROR){
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
522
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
523
gpgme_strsource(rc), gpgme_strerror(rc));
234
526
while(engine_info != NULL){
273
568
ssize_t plaintext_length = 0;
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
571
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
279
574
/* Create new GPGME data buffer from memory cryptotext */
280
575
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
282
577
if(rc != GPG_ERR_NO_ERROR){
283
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
284
gpgme_strsource(rc), gpgme_strerror(rc));
578
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
579
gpgme_strsource(rc), gpgme_strerror(rc));
288
583
/* Create new empty GPGME data buffer for the plaintext */
289
584
rc = gpgme_data_new(&dh_plain);
290
585
if(rc != GPG_ERR_NO_ERROR){
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
586
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
587
gpgme_strsource(rc), gpgme_strerror(rc));
293
588
gpgme_data_release(dh_crypto);
297
592
/* Decrypt data from the cryptotext data buffer to the plaintext
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
594
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
300
595
if(rc != GPG_ERR_NO_ERROR){
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
596
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
597
gpgme_strsource(rc), gpgme_strerror(rc));
303
598
plaintext_length = -1;
305
600
gpgme_decrypt_result_t result;
306
result = gpgme_op_decrypt_result(mc.ctx);
601
result = gpgme_op_decrypt_result(mc->ctx);
307
602
if(result == NULL){
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
603
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
605
if(result->unsupported_algorithm != NULL) {
606
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
607
result->unsupported_algorithm);
609
fprintf_plus(stderr, "Wrong key usage: %s\n",
610
result->wrong_key_usage ? "Yes" : "No");
314
611
if(result->file_name != NULL){
315
fprintf(stderr, "File name: %s\n", result->file_name);
612
fprintf_plus(stderr, "File name: %s\n", result->file_name);
317
gpgme_recipient_t recipient;
318
recipient = result->recipients;
319
while(recipient != NULL){
320
fprintf(stderr, "Public key algorithm: %s\n",
321
gpgme_pubkey_algo_name(recipient->pubkey_algo));
322
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
323
fprintf(stderr, "Secret key available: %s\n",
324
recipient->status == GPG_ERR_NO_SECKEY
326
recipient = recipient->next;
615
for(gpgme_recipient_t r = result->recipients; r != NULL;
617
fprintf_plus(stderr, "Public key algorithm: %s\n",
618
gpgme_pubkey_algo_name(r->pubkey_algo));
619
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
620
fprintf_plus(stderr, "Secret key available: %s\n",
621
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
425
722
/* OpenPGP credentials */
426
gnutls_certificate_allocate_credentials(&mc.cred);
723
ret = gnutls_certificate_allocate_credentials(&mc->cred);
427
724
if(ret != GNUTLS_E_SUCCESS){
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
432
safer_gnutls_strerror(ret));
433
gnutls_global_deinit();
725
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
726
safer_gnutls_strerror(ret));
438
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
439
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
731
fprintf_plus(stderr, "Attempting to use public key %s and"
732
" private key %s as GnuTLS credentials\n",
737
#if GNUTLS_VERSION_NUMBER >= 0x030606
738
ret = gnutls_certificate_set_rawpk_key_file
739
(mc->cred, pubkeyfilename, seckeyfilename,
740
GNUTLS_X509_FMT_PEM, /* format */
743
GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,
745
0, /* names_length */
747
GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,
748
0); /* pkcs11_flags */
749
#elif GNUTLS_VERSION_NUMBER < 0x030600
443
750
ret = gnutls_certificate_set_openpgp_key_file
444
(mc.cred, pubkeyfilename, seckeyfilename,
751
(mc->cred, pubkeyfilename, seckeyfilename,
445
752
GNUTLS_OPENPGP_FMT_BASE64);
754
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
446
756
if(ret != GNUTLS_E_SUCCESS){
448
"Error[%d] while reading the OpenPGP key pair ('%s',"
449
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
450
fprintf(stderr, "The GnuTLS error is: %s\n",
451
safer_gnutls_strerror(ret));
758
"Error[%d] while reading the key pair ('%s',"
759
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
760
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
761
safer_gnutls_strerror(ret));
455
765
/* GnuTLS server initialization */
456
ret = gnutls_dh_params_init(&mc.dh_params);
457
if(ret != GNUTLS_E_SUCCESS){
458
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
459
" %s\n", safer_gnutls_strerror(ret));
462
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
463
if(ret != GNUTLS_E_SUCCESS){
464
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
465
safer_gnutls_strerror(ret));
469
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
766
ret = gnutls_dh_params_init(&mc->dh_params);
767
if(ret != GNUTLS_E_SUCCESS){
768
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
769
" initialization: %s\n",
770
safer_gnutls_strerror(ret));
773
/* If a Diffie-Hellman parameters file was given, try to use it */
774
if(dhparamsfilename != NULL){
775
gnutls_datum_t params = { .data = NULL, .size = 0 };
777
int dhpfile = open(dhparamsfilename, O_RDONLY);
780
dhparamsfilename = NULL;
783
size_t params_capacity = 0;
785
params_capacity = incbuffer((char **)¶ms.data,
787
(size_t)params_capacity);
788
if(params_capacity == 0){
789
perror_plus("incbuffer");
792
dhparamsfilename = NULL;
795
ssize_t bytes_read = read(dhpfile,
796
params.data + params.size,
802
/* check bytes_read for failure */
807
dhparamsfilename = NULL;
810
params.size += (unsigned int)bytes_read;
812
ret = close(dhpfile);
814
perror_plus("close");
816
if(params.data == NULL){
817
dhparamsfilename = NULL;
819
if(dhparamsfilename == NULL){
822
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
823
GNUTLS_X509_FMT_PEM);
824
if(ret != GNUTLS_E_SUCCESS){
825
fprintf_plus(stderr, "Failed to parse DH parameters in file"
826
" \"%s\": %s\n", dhparamsfilename,
827
safer_gnutls_strerror(ret));
828
dhparamsfilename = NULL;
833
if(dhparamsfilename == NULL){
834
if(mc->dh_bits == 0){
835
#if GNUTLS_VERSION_NUMBER < 0x030600
836
/* Find out the optimal number of DH bits */
837
/* Try to read the private key file */
838
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
840
int secfile = open(seckeyfilename, O_RDONLY);
845
size_t buffer_capacity = 0;
847
buffer_capacity = incbuffer((char **)&buffer.data,
849
(size_t)buffer_capacity);
850
if(buffer_capacity == 0){
851
perror_plus("incbuffer");
856
ssize_t bytes_read = read(secfile,
857
buffer.data + buffer.size,
863
/* check bytes_read for failure */
870
buffer.size += (unsigned int)bytes_read;
874
/* If successful, use buffer to parse private key */
875
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
876
if(buffer.data != NULL){
878
gnutls_openpgp_privkey_t privkey = NULL;
879
ret = gnutls_openpgp_privkey_init(&privkey);
880
if(ret != GNUTLS_E_SUCCESS){
881
fprintf_plus(stderr, "Error initializing OpenPGP key"
883
safer_gnutls_strerror(ret));
887
ret = gnutls_openpgp_privkey_import
888
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
889
if(ret != GNUTLS_E_SUCCESS){
890
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
891
safer_gnutls_strerror(ret));
897
/* Use private key to suggest an appropriate
899
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
900
gnutls_openpgp_privkey_deinit(privkey);
902
fprintf_plus(stderr, "This OpenPGP key implies using"
903
" a GnuTLS security parameter \"%s\".\n",
904
safe_string(gnutls_sec_param_get_name
910
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
911
/* Err on the side of caution */
912
sec_param = GNUTLS_SEC_PARAM_ULTRA;
914
fprintf_plus(stderr, "Falling back to security parameter"
916
safe_string(gnutls_sec_param_get_name
921
unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
925
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
926
" implies %u DH bits; using that.\n",
927
safe_string(gnutls_sec_param_get_name
932
fprintf_plus(stderr, "Failed to get implied number of DH"
933
" bits for security parameter \"%s\"): %s\n",
934
safe_string(gnutls_sec_param_get_name
936
safer_gnutls_strerror(ret));
940
} else { /* dh_bits != 0 */
942
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
945
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
946
if(ret != GNUTLS_E_SUCCESS){
947
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
948
" bits): %s\n", mc->dh_bits,
949
safer_gnutls_strerror(ret));
952
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
475
gnutls_certificate_free_credentials(mc.cred);
476
gnutls_global_deinit();
477
gnutls_dh_params_deinit(mc.dh_params);
960
gnutls_certificate_free_credentials(mc->cred);
961
gnutls_dh_params_deinit(mc->dh_params);
481
static int init_gnutls_session(gnutls_session_t *session){
965
__attribute__((nonnull, warn_unused_result))
966
static int init_gnutls_session(gnutls_session_t *session,
483
969
/* GnuTLS session creation */
485
ret = gnutls_init(session, GNUTLS_SERVER);
971
ret = gnutls_init(session, (GNUTLS_SERVER
972
#if GNUTLS_VERSION_NUMBER >= 0x030506
975
#if GNUTLS_VERSION_NUMBER >= 0x030606
976
| GNUTLS_ENABLE_RAWPK
489
982
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
490
983
if(ret != GNUTLS_E_SUCCESS){
491
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
492
safer_gnutls_strerror(ret));
985
"Error in GnuTLS session initialization: %s\n",
986
safer_gnutls_strerror(ret));
498
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
992
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
500
994
gnutls_deinit(*session);
503
997
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
504
998
if(ret != GNUTLS_E_SUCCESS){
505
fprintf(stderr, "Syntax error at: %s\n", err);
506
fprintf(stderr, "GnuTLS error: %s\n",
507
safer_gnutls_strerror(ret));
999
fprintf_plus(stderr, "Syntax error at: %s\n", err);
1000
fprintf_plus(stderr, "GnuTLS error: %s\n",
1001
safer_gnutls_strerror(ret));
508
1002
gnutls_deinit(*session);
537
1029
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
538
1030
__attribute__((unused)) const char *txt){}
1032
/* Helper function to add_local_route() and delete_local_route() */
1033
__attribute__((nonnull, warn_unused_result))
1034
static bool add_delete_local_route(const bool add,
1035
const char *address,
1036
AvahiIfIndex if_index){
1038
char helper[] = "mandos-client-iprouteadddel";
1039
char add_arg[] = "add";
1040
char delete_arg[] = "delete";
1041
char debug_flag[] = "--debug";
1042
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1043
if(pluginhelperdir == NULL){
1045
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
1046
" variable not set; cannot run helper\n");
1051
char interface[IF_NAMESIZE];
1052
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1053
perror_plus("if_indextoname");
1057
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1059
perror_plus("open(\"/dev/null\", O_RDONLY)");
1065
/* Raise privileges */
1066
errno = raise_privileges_permanently();
1068
perror_plus("Failed to raise privileges");
1069
/* _exit(EX_NOPERM); */
1075
perror_plus("setgid");
1079
/* Reset supplementary groups */
1081
ret = setgroups(0, NULL);
1083
perror_plus("setgroups");
1088
ret = dup2(devnull, STDIN_FILENO);
1090
perror_plus("dup2(devnull, STDIN_FILENO)");
1094
ret = close(devnull);
1096
perror_plus("close");
1098
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1100
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1103
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1108
if(helperdir_fd == -1){
1109
perror_plus("open");
1110
_exit(EX_UNAVAILABLE);
1112
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1114
if(helper_fd == -1){
1115
perror_plus("openat");
1116
close(helperdir_fd);
1117
_exit(EX_UNAVAILABLE);
1119
close(helperdir_fd);
1121
#pragma GCC diagnostic push
1122
#pragma GCC diagnostic ignored "-Wcast-qual"
1124
if(fexecve(helper_fd, (char *const [])
1125
{ helper, add ? add_arg : delete_arg, (char *)address,
1126
interface, debug ? debug_flag : NULL, NULL },
1129
#pragma GCC diagnostic pop
1131
perror_plus("fexecve");
1132
_exit(EXIT_FAILURE);
1136
perror_plus("fork");
1140
ret = close(devnull);
1142
perror_plus("close");
1148
pret = waitpid(pid, &status, 0);
1149
if(pret == -1 and errno == EINTR and quit_now){
1150
int errno_raising = 0;
1151
if((errno = raise_privileges()) != 0){
1152
errno_raising = errno;
1153
perror_plus("Failed to raise privileges in order to"
1154
" kill helper program");
1156
if(kill(pid, SIGTERM) == -1){
1157
perror_plus("kill");
1159
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1160
perror_plus("Failed to lower privileges after killing"
1165
} while(pret == -1 and errno == EINTR);
1167
perror_plus("waitpid");
1170
if(WIFEXITED(status)){
1171
if(WEXITSTATUS(status) != 0){
1172
fprintf_plus(stderr, "Error: iprouteadddel exited"
1173
" with status %d\n", WEXITSTATUS(status));
1178
if(WIFSIGNALED(status)){
1179
fprintf_plus(stderr, "Error: iprouteadddel died by"
1180
" signal %d\n", WTERMSIG(status));
1183
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1187
__attribute__((nonnull, warn_unused_result))
1188
static bool add_local_route(const char *address,
1189
AvahiIfIndex if_index){
1191
fprintf_plus(stderr, "Adding route to %s\n", address);
1193
return add_delete_local_route(true, address, if_index);
1196
__attribute__((nonnull, warn_unused_result))
1197
static bool delete_local_route(const char *address,
1198
AvahiIfIndex if_index){
1200
fprintf_plus(stderr, "Removing route to %s\n", address);
1202
return add_delete_local_route(false, address, if_index);
540
1205
/* Called when a Mandos server is found */
541
static int start_mandos_communication(const char *ip, uint16_t port,
1206
__attribute__((nonnull, warn_unused_result))
1207
static int start_mandos_communication(const char *ip, in_port_t port,
542
1208
AvahiIfIndex if_index,
1209
int af, mandos_context *mc){
544
1210
int ret, tcp_sd = -1;
547
struct sockaddr_in in;
548
struct sockaddr_in6 in6;
1212
struct sockaddr_storage to;
550
1213
char *buffer = NULL;
551
1214
char *decrypted_buffer = NULL;
552
1215
size_t buffer_length = 0;
651
1343
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
652
1344
char interface[IF_NAMESIZE];
653
1345
if(if_indextoname((unsigned int)if_index, interface) == NULL){
654
perror("if_indextoname");
1346
perror_plus("if_indextoname");
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
1348
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1349
"\n", ip, interface, (uintmax_t)port);
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1352
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1353
ip, (uintmax_t)port);
663
1355
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
664
1356
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
667
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
670
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
676
if(strcmp(addrstr, ip) != 0){
677
fprintf(stderr, "Canonical address form: %s\n", addrstr);
688
ret = connect(tcp_sd, &to.in6, sizeof(to));
690
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
693
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
1358
ret = getnameinfo((struct sockaddr *)&to,
1359
sizeof(struct sockaddr_in6),
1360
addrstr, sizeof(addrstr), NULL, 0,
1363
ret = getnameinfo((struct sockaddr *)&to,
1364
sizeof(struct sockaddr_in),
1365
addrstr, sizeof(addrstr), NULL, 0,
1368
if(ret == EAI_SYSTEM){
1369
perror_plus("getnameinfo");
1370
} else if(ret != 0) {
1371
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1372
} else if(strcmp(addrstr, ip) != 0){
1373
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1384
ret = connect(tcp_sd, (struct sockaddr *)&to,
1385
sizeof(struct sockaddr_in6));
1387
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1388
sizeof(struct sockaddr_in));
1391
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1392
and if_index != AVAHI_IF_UNSPEC
1393
and connect_to == NULL
1394
and not route_added and
1395
((af == AF_INET6 and not
1396
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1398
or (af == AF_INET and
1399
/* Not a a IPv4LL address */
1400
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1401
& 0xFFFF0000L) != 0xA9FE0000L))){
1402
/* Work around Avahi bug - Avahi does not announce link-local
1403
addresses if it has a global address, so local hosts with
1404
*only* a link-local address (e.g. Mandos clients) cannot
1405
connect to a Mandos server announced by Avahi on a server
1406
host with a global address. Work around this by retrying
1407
with an explicit route added with the server's address.
1409
Avahi bug reference:
1410
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1411
https://bugs.debian.org/587961
1414
fprintf_plus(stderr, "Mandos server unreachable, trying"
1418
route_added = add_local_route(ip, if_index);
1424
if(errno != ECONNREFUSED or debug){
1426
perror_plus("connect");
706
1439
const char *out = mandos_protocol_version;
1019
1794
signal_received = sig;
1020
1795
int old_errno = errno;
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1796
/* set main loop to exit */
1797
if(simple_poll != NULL){
1798
avahi_simple_poll_quit(simple_poll);
1024
1800
errno = old_errno;
1803
__attribute__((nonnull, warn_unused_result))
1804
bool get_flags(const char *ifname, struct ifreq *ifr){
1808
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1811
perror_plus("socket");
1815
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1816
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1817
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1821
perror_plus("ioctl SIOCGIFFLAGS");
1824
if((close(s) == -1) and debug){
1826
perror_plus("close");
1831
if((close(s) == -1) and debug){
1833
perror_plus("close");
1839
__attribute__((nonnull, warn_unused_result))
1840
bool good_flags(const char *ifname, const struct ifreq *ifr){
1842
/* Reject the loopback device */
1843
if(ifr->ifr_flags & IFF_LOOPBACK){
1845
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1850
/* Accept point-to-point devices only if connect_to is specified */
1851
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1853
fprintf_plus(stderr, "Accepting point-to-point interface"
1854
" \"%s\"\n", ifname);
1858
/* Otherwise, reject non-broadcast-capable devices */
1859
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1861
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1862
" \"%s\"\n", ifname);
1866
/* Reject non-ARP interfaces (including dummy interfaces) */
1867
if(ifr->ifr_flags & IFF_NOARP){
1869
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1875
/* Accept this device */
1877
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1028
1883
* This function determines if a directory entry in /sys/class/net
1029
1884
* corresponds to an acceptable network device.
1030
1885
* (This function is passed to scandir(3) as a filter function.)
1887
__attribute__((nonnull, warn_unused_result))
1032
1888
int good_interface(const struct dirent *if_entry){
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1041
1889
if(if_entry->d_name[0] == '.'){
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1049
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1050
/* read line from flags_fd */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1052
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1053
flagstring[(size_t)to_read] = '\0';
1054
if(flagstring == NULL){
1060
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1894
if(not get_flags(if_entry->d_name, &ifr)){
1896
fprintf_plus(stderr, "Failed to get flags for interface "
1897
"\"%s\"\n", if_entry->d_name);
1902
if(not good_flags(if_entry->d_name, &ifr)){
1909
* This function determines if a network interface is up.
1911
__attribute__((nonnull, warn_unused_result))
1912
bool interface_is_up(const char *interface){
1914
if(not get_flags(interface, &ifr)){
1916
fprintf_plus(stderr, "Failed to get flags for interface "
1917
"\"%s\"\n", interface);
1922
return (bool)(ifr.ifr_flags & IFF_UP);
1926
* This function determines if a network interface is running
1928
__attribute__((nonnull, warn_unused_result))
1929
bool interface_is_running(const char *interface){
1931
if(not get_flags(interface, &ifr)){
1933
fprintf_plus(stderr, "Failed to get flags for interface "
1934
"\"%s\"\n", interface);
1939
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1942
__attribute__((nonnull, pure, warn_unused_result))
1943
int notdotentries(const struct dirent *direntry){
1944
/* Skip "." and ".." */
1945
if(direntry->d_name[0] == '.'
1946
and (direntry->d_name[1] == '\0'
1947
or (direntry->d_name[1] == '.'
1948
and direntry->d_name[2] == '\0'))){
1954
/* Is this directory entry a runnable program? */
1955
__attribute__((nonnull, warn_unused_result))
1956
int runnable_hook(const struct dirent *direntry){
1961
if((direntry->d_name)[0] == '\0'){
1966
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1967
"abcdefghijklmnopqrstuvwxyz"
1970
if((direntry->d_name)[sret] != '\0'){
1971
/* Contains non-allowed characters */
1973
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1979
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1982
perror_plus("Could not stat hook");
1986
if(not (S_ISREG(st.st_mode))){
1987
/* Not a regular file */
1989
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1994
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1995
/* Not executable */
1997
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
2003
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
2009
__attribute__((nonnull, warn_unused_result))
2010
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
2011
mandos_context *mc){
2013
struct timespec now;
2014
struct timespec waited_time;
2015
intmax_t block_time;
2018
if(mc->current_server == NULL){
2020
fprintf_plus(stderr, "Wait until first server is found."
2023
ret = avahi_simple_poll_iterate(s, -1);
2026
fprintf_plus(stderr, "Check current_server if we should run"
2029
/* the current time */
2030
ret = clock_gettime(CLOCK_MONOTONIC, &now);
2032
perror_plus("clock_gettime");
2035
/* Calculating in ms how long time between now and server
2036
who we visted longest time ago. Now - last seen. */
2037
waited_time.tv_sec = (now.tv_sec
2038
- mc->current_server->last_seen.tv_sec);
2039
waited_time.tv_nsec = (now.tv_nsec
2040
- mc->current_server->last_seen.tv_nsec);
2041
/* total time is 10s/10,000ms.
2042
Converting to s from ms by dividing by 1,000,
2043
and ns to ms by dividing by 1,000,000. */
2044
block_time = ((retry_interval
2045
- ((intmax_t)waited_time.tv_sec * 1000))
2046
- ((intmax_t)waited_time.tv_nsec / 1000000));
2049
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
2053
if(block_time <= 0){
2054
ret = start_mandos_communication(mc->current_server->ip,
2055
mc->current_server->port,
2056
mc->current_server->if_index,
2057
mc->current_server->af, mc);
2059
avahi_simple_poll_quit(s);
2062
ret = clock_gettime(CLOCK_MONOTONIC,
2063
&mc->current_server->last_seen);
2065
perror_plus("clock_gettime");
2068
mc->current_server = mc->current_server->next;
2069
block_time = 0; /* Call avahi to find new Mandos
2070
servers, but don't block */
2073
ret = avahi_simple_poll_iterate(s, (int)block_time);
2076
if(ret > 0 or errno != EINTR){
2077
return (ret != 1) ? ret : 0;
2083
__attribute__((nonnull))
2084
void run_network_hooks(const char *mode, const char *interface,
2086
struct dirent **direntries = NULL;
2087
if(hookdir_fd == -1){
2088
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2090
if(hookdir_fd == -1){
2091
if(errno == ENOENT){
2093
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2094
" found\n", hookdir);
2097
perror_plus("open");
2102
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2104
perror_plus("open(\"/dev/null\", O_RDONLY)");
2107
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2108
runnable_hook, alphasort);
2110
perror_plus("scandir");
2114
struct dirent *direntry;
2116
for(int i = 0; i < numhooks; i++){
2117
direntry = direntries[i];
2119
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2122
pid_t hook_pid = fork();
2125
/* Raise privileges */
2126
errno = raise_privileges_permanently();
2128
perror_plus("Failed to raise privileges");
2135
perror_plus("setgid");
2138
/* Reset supplementary groups */
2140
ret = setgroups(0, NULL);
2142
perror_plus("setgroups");
2145
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2147
perror_plus("setenv");
2150
ret = setenv("DEVICE", interface, 1);
2152
perror_plus("setenv");
2155
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2157
perror_plus("setenv");
2160
ret = setenv("MODE", mode, 1);
2162
perror_plus("setenv");
2166
ret = asprintf(&delaystring, "%f", (double)delay);
2168
perror_plus("asprintf");
2171
ret = setenv("DELAY", delaystring, 1);
2174
perror_plus("setenv");
2178
if(connect_to != NULL){
2179
ret = setenv("CONNECT", connect_to, 1);
2181
perror_plus("setenv");
2185
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2189
perror_plus("openat");
2190
_exit(EXIT_FAILURE);
2192
if(close(hookdir_fd) == -1){
2193
perror_plus("close");
2194
_exit(EXIT_FAILURE);
2196
ret = dup2(devnull, STDIN_FILENO);
2198
perror_plus("dup2(devnull, STDIN_FILENO)");
2201
ret = close(devnull);
2203
perror_plus("close");
2206
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2208
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2211
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2213
perror_plus("fexecve");
2214
_exit(EXIT_FAILURE);
2218
perror_plus("fork");
2223
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2224
perror_plus("waitpid");
2228
if(WIFEXITED(status)){
2229
if(WEXITSTATUS(status) != 0){
2230
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2231
" with status %d\n", direntry->d_name,
2232
WEXITSTATUS(status));
2236
} else if(WIFSIGNALED(status)){
2237
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2238
" signal %d\n", direntry->d_name,
2243
fprintf_plus(stderr, "Warning: network hook \"%s\""
2244
" crashed\n", direntry->d_name);
2250
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2256
if(close(hookdir_fd) == -1){
2257
perror_plus("close");
2264
__attribute__((nonnull, warn_unused_result))
2265
int bring_up_interface(const char *const interface,
2267
int old_errno = errno;
2269
struct ifreq network;
2270
unsigned int if_index = if_nametoindex(interface);
2272
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2282
if(not interface_is_up(interface)){
2284
int ioctl_errno = 0;
2285
if(not get_flags(interface, &network)){
2287
fprintf_plus(stderr, "Failed to get flags for interface "
2288
"\"%s\"\n", interface);
2292
network.ifr_flags |= IFF_UP; /* set flag */
2294
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2297
perror_plus("socket");
2305
perror_plus("close");
2312
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2316
/* Raise privileges */
2317
ret_errno = raise_privileges();
2320
perror_plus("Failed to raise privileges");
2325
bool restore_loglevel = false;
2327
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2328
messages about the network interface to mess up the prompt */
2329
ret_linux = klogctl(8, NULL, 5);
2330
if(ret_linux == -1){
2331
perror_plus("klogctl");
2333
restore_loglevel = true;
2336
#endif /* __linux__ */
2337
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2338
ioctl_errno = errno;
2340
if(restore_loglevel){
2341
ret_linux = klogctl(7, NULL, 0);
2342
if(ret_linux == -1){
2343
perror_plus("klogctl");
2346
#endif /* __linux__ */
2348
/* If raise_privileges() succeeded above */
2350
/* Lower privileges */
2351
ret_errno = lower_privileges();
2354
perror_plus("Failed to lower privileges");
2358
/* Close the socket */
2361
perror_plus("close");
2364
if(ret_setflags == -1){
2365
errno = ioctl_errno;
2366
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2371
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2375
/* Sleep checking until interface is running.
2376
Check every 0.25s, up to total time of delay */
2377
for(int i = 0; i < delay * 4; i++){
2378
if(interface_is_running(interface)){
1077
tmpmax = strtoimax(flagstring, &tmp, 0);
1078
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1079
and not (isspace(*tmp)))
1080
or tmpmax != (ifreq_flags)tmpmax){
1082
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1083
flagstring, if_entry->d_name);
1089
ifreq_flags flags = (ifreq_flags)tmpmax;
1090
/* Reject the loopback device */
1091
if(flags & IFF_LOOPBACK){
1093
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1098
/* Accept point-to-point devices only if connect_to is specified */
1099
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1101
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1106
/* Otherwise, reject non-broadcast-capable devices */
1107
if(not (flags & IFF_BROADCAST)){
1109
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1114
/* Accept this device */
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
2381
struct timespec sleeptime = { .tv_nsec = 250000000 };
2382
ret = nanosleep(&sleeptime, NULL);
2383
if(ret == -1 and errno != EINTR){
2384
perror_plus("nanosleep");
2392
__attribute__((nonnull, warn_unused_result))
2393
int take_down_interface(const char *const interface){
2394
int old_errno = errno;
2395
struct ifreq network;
2396
unsigned int if_index = if_nametoindex(interface);
2398
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2402
if(interface_is_up(interface)){
2404
int ioctl_errno = 0;
2405
if(not get_flags(interface, &network) and debug){
2407
fprintf_plus(stderr, "Failed to get flags for interface "
2408
"\"%s\"\n", interface);
2412
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2414
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2417
perror_plus("socket");
2423
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2427
/* Raise privileges */
2428
ret_errno = raise_privileges();
2431
perror_plus("Failed to raise privileges");
2434
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2435
ioctl_errno = errno;
2437
/* If raise_privileges() succeeded above */
2439
/* Lower privileges */
2440
ret_errno = lower_privileges();
2443
perror_plus("Failed to lower privileges");
2447
/* Close the socket */
2448
int ret = close(sd);
2450
perror_plus("close");
2453
if(ret_setflags == -1){
2454
errno = ioctl_errno;
2455
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2460
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1122
2468
int main(int argc, char *argv[]){
2469
mandos_context mc = { .server = NULL, .dh_bits = 0,
2470
#if GNUTLS_VERSION_NUMBER >= 0x030606
2471
.priority = "SECURE128:!CTYPE-X.509"
2472
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2474
#elif GNUTLS_VERSION_NUMBER < 0x030600
2475
.priority = "SECURE256:!CTYPE-X.509"
2476
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2478
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2480
.current_server = NULL, .interfaces = NULL,
2481
.interfaces_size = 0 };
1123
2482
AvahiSServiceBrowser *sb = NULL;
1126
2485
intmax_t tmpmax;
1128
2487
int exitcode = EXIT_SUCCESS;
1129
const char *interface = "";
1130
struct ifreq network;
1132
bool take_down_interface = false;
1135
char tempdir[] = "/tmp/mandosXXXXXX";
1136
bool tempdir_created = false;
2488
char *interfaces_to_take_down = NULL;
2489
size_t interfaces_to_take_down_size = 0;
2490
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2491
char old_tempdir[] = "/tmp/mandosXXXXXX";
2492
char *tempdir = NULL;
1137
2493
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1138
2494
const char *seckey = PATHDIR "/" SECKEY;
1139
2495
const char *pubkey = PATHDIR "/" PUBKEY;
2496
#if GNUTLS_VERSION_NUMBER >= 0x030606
2497
const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;
2498
const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;
2500
const char *dh_params_file = NULL;
2501
char *interfaces_hooks = NULL;
1141
2503
bool gnutls_initialized = false;
1142
2504
bool gpgme_initialized = false;
1143
2505
float delay = 2.5f;
2506
double retry_interval = 10; /* 10s between trying a server and
2507
retrying the same server again */
1145
2509
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1146
2510
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2718
/* Re-raise privileges */
2719
ret = raise_privileges();
2722
perror_plus("Failed to raise privileges");
2726
/* Work around Debian bug #633582:
2727
<https://bugs.debian.org/633582> */
2729
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2730
int seckey_fd = open(seckey, O_RDONLY);
2731
if(seckey_fd == -1){
2732
perror_plus("open");
2734
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2736
perror_plus("fstat");
2738
if(S_ISREG(st.st_mode)
2739
and st.st_uid == 0 and st.st_gid == 0){
2740
ret = fchown(seckey_fd, uid, gid);
2742
perror_plus("fchown");
2750
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2751
int pubkey_fd = open(pubkey, O_RDONLY);
2752
if(pubkey_fd == -1){
2753
perror_plus("open");
2755
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2757
perror_plus("fstat");
2759
if(S_ISREG(st.st_mode)
2760
and st.st_uid == 0 and st.st_gid == 0){
2761
ret = fchown(pubkey_fd, uid, gid);
2763
perror_plus("fchown");
2771
if(dh_params_file != NULL
2772
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2773
int dhparams_fd = open(dh_params_file, O_RDONLY);
2774
if(dhparams_fd == -1){
2775
perror_plus("open");
2777
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2779
perror_plus("fstat");
2781
if(S_ISREG(st.st_mode)
2782
and st.st_uid == 0 and st.st_gid == 0){
2783
ret = fchown(dhparams_fd, uid, gid);
2785
perror_plus("fchown");
2793
/* Work around Debian bug #981302
2794
<https://bugs.debian.org/981302> */
2795
if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){
2796
ret = symlink("/proc/self/fd", "/dev/fd");
2798
perror_plus("Failed to create /dev/fd symlink");
2802
/* Lower privileges */
2803
ret = lower_privileges();
2806
perror_plus("Failed to lower privileges");
2811
/* Remove invalid interface names (except "none") */
2813
char *interface = NULL;
2814
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2816
if(strcmp(interface, "none") != 0
2817
and if_nametoindex(interface) == 0){
2818
if(interface[0] != '\0'){
2819
fprintf_plus(stderr, "Not using nonexisting interface"
2820
" \"%s\"\n", interface);
2822
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2828
/* Run network hooks */
2830
if(mc.interfaces != NULL){
2831
interfaces_hooks = malloc(mc.interfaces_size);
2832
if(interfaces_hooks == NULL){
2833
perror_plus("malloc");
2836
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2837
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2839
run_network_hooks("start", interfaces_hooks != NULL ?
2840
interfaces_hooks : "", delay);
1295
2844
avahi_set_log_function(empty_log);
1298
if(interface[0] == '\0'){
1299
struct dirent **direntries;
1300
ret = scandir(sys_class_net, &direntries, good_interface,
1303
/* Pick the first good interface */
1304
interface = strdup(direntries[0]->d_name);
1306
fprintf(stderr, "Using interface \"%s\"\n", interface);
1308
if(interface == NULL){
1311
exitcode = EXIT_FAILURE;
1317
fprintf(stderr, "Could not find a network interface\n");
1318
exitcode = EXIT_FAILURE;
1323
2847
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1324
2848
from the signal handler */
1325
2849
/* Initialize the pseudo-RNG for Avahi */
1326
2850
srand((unsigned int) time(NULL));
1327
mc.simple_poll = avahi_simple_poll_new();
1328
if(mc.simple_poll == NULL){
1329
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2851
simple_poll = avahi_simple_poll_new();
2852
if(simple_poll == NULL){
2853
fprintf_plus(stderr,
2854
"Avahi: Failed to create simple poll object.\n");
1330
2855
exitcode = EX_UNAVAILABLE;
1357
2882
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1359
perror("sigaction");
2884
perror_plus("sigaction");
1360
2885
return EX_OSERR;
1362
2887
if(old_sigterm_action.sa_handler != SIG_IGN){
1363
2888
ret = sigaction(SIGINT, &sigterm_action, NULL);
1365
perror("sigaction");
2890
perror_plus("sigaction");
1366
2891
exitcode = EX_OSERR;
1370
2895
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1372
perror("sigaction");
2897
perror_plus("sigaction");
1373
2898
return EX_OSERR;
1375
2900
if(old_sigterm_action.sa_handler != SIG_IGN){
1376
2901
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1378
perror("sigaction");
2903
perror_plus("sigaction");
1379
2904
exitcode = EX_OSERR;
1383
2908
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1385
perror("sigaction");
2910
perror_plus("sigaction");
1386
2911
return EX_OSERR;
1388
2913
if(old_sigterm_action.sa_handler != SIG_IGN){
1389
2914
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1391
perror("sigaction");
1392
exitcode = EX_OSERR;
1397
/* If the interface is down, bring it up */
1398
if(strcmp(interface, "none") != 0){
1399
if_index = (AvahiIfIndex) if_nametoindex(interface);
1401
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1402
exitcode = EX_UNAVAILABLE;
1410
/* Re-raise priviliges */
1418
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1419
messages about the network interface to mess up the prompt */
1420
ret = klogctl(8, NULL, 5);
1421
bool restore_loglevel = true;
1423
restore_loglevel = false;
1426
#endif /* __linux__ */
1428
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1431
exitcode = EX_OSERR;
1433
if(restore_loglevel){
1434
ret = klogctl(7, NULL, 0);
1439
#endif /* __linux__ */
1440
/* Lower privileges */
1448
strcpy(network.ifr_name, interface);
1449
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1451
perror("ioctl SIOCGIFFLAGS");
1453
if(restore_loglevel){
1454
ret = klogctl(7, NULL, 0);
1459
#endif /* __linux__ */
1460
exitcode = EX_OSERR;
1461
/* Lower privileges */
1469
if((network.ifr_flags & IFF_UP) == 0){
1470
network.ifr_flags |= IFF_UP;
1471
take_down_interface = true;
1472
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1474
take_down_interface = false;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1476
exitcode = EX_OSERR;
1478
if(restore_loglevel){
1479
ret = klogctl(7, NULL, 0);
2916
perror_plus("sigaction");
2917
exitcode = EX_OSERR;
2922
/* If no interfaces were specified, make a list */
2923
if(mc.interfaces == NULL){
2924
struct dirent **direntries = NULL;
2925
/* Look for any good interfaces */
2926
ret = scandir(sys_class_net, &direntries, good_interface,
2929
/* Add all found interfaces to interfaces list */
2930
for(int i = 0; i < ret; ++i){
2931
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2932
direntries[i]->d_name);
2935
perror_plus("argz_add");
2936
free(direntries[i]);
2940
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2941
direntries[i]->d_name);
2943
free(direntries[i]);
2950
fprintf_plus(stderr, "Could not find a network interface\n");
2951
exitcode = EXIT_FAILURE;
2956
/* Bring up interfaces which are down, and remove any "none"s */
2958
char *interface = NULL;
2959
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2961
/* If interface name is "none", stop bringing up interfaces.
2962
Also remove all instances of "none" from the list */
2963
if(strcmp(interface, "none") == 0){
2964
argz_delete(&mc.interfaces, &mc.interfaces_size,
2967
while((interface = argz_next(mc.interfaces,
2968
mc.interfaces_size, interface))){
2969
if(strcmp(interface, "none") == 0){
2970
argz_delete(&mc.interfaces, &mc.interfaces_size,
1484
#endif /* __linux__ */
1485
/* Lower privileges */
1494
/* sleep checking until interface is running */
1495
for(int i=0; i < delay * 4; i++){
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_RUNNING){
1502
struct timespec sleeptime = { .tv_nsec = 250000000 };
1503
ret = nanosleep(&sleeptime, NULL);
1504
if(ret == -1 and errno != EINTR){
1505
perror("nanosleep");
1508
if(not take_down_interface){
1509
/* We won't need the socket anymore */
1510
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1516
if(restore_loglevel){
1517
/* Restores kernel loglevel to default */
1518
ret = klogctl(7, NULL, 0);
1523
#endif /* __linux__ */
1524
/* Lower privileges */
1526
if(take_down_interface){
1527
/* Lower privileges */
1533
/* Lower privileges permanently */
2977
bool interface_was_up = interface_is_up(interface);
2978
errno = bring_up_interface(interface, delay);
2979
if(not interface_was_up){
2981
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2982
" %s\n", interface, strerror(errno));
2984
errno = argz_add(&interfaces_to_take_down,
2985
&interfaces_to_take_down_size,
2988
perror_plus("argz_add");
2993
if(debug and (interfaces_to_take_down == NULL)){
2994
fprintf_plus(stderr, "No interfaces were brought up\n");
2998
/* If we only got one interface, explicitly use only that one */
2999
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
3001
fprintf_plus(stderr, "Using only interface \"%s\"\n",
3004
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1545
ret = init_gnutls_global(pubkey, seckey);
3011
#if GNUTLS_VERSION_NUMBER >= 0x030606
3012
ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);
3013
#elif GNUTLS_VERSION_NUMBER < 0x030600
3014
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
3016
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
1547
fprintf(stderr, "init_gnutls_global failed\n");
3019
fprintf_plus(stderr, "init_gnutls_global failed\n");
1548
3020
exitcode = EX_UNAVAILABLE;
1719
3222
gpgme_release(mc.ctx);
1722
/* Take down the network interface */
1723
if(take_down_interface){
1724
/* Re-raise priviliges */
1731
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1733
perror("ioctl SIOCGIFFLAGS");
1734
} else if(network.ifr_flags & IFF_UP) {
1735
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1736
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1745
/* Lower privileges permanently */
1754
/* Removes the temp directory used by GPGME */
1755
if(tempdir_created){
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1760
if(errno != ENOENT){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1769
/* Skip "." and ".." */
1770
if(direntry->d_name[0] == '.'
1771
and (direntry->d_name[1] == '\0'
1772
or (direntry->d_name[1] == '.'
1773
and direntry->d_name[2] == '\0'))){
1776
char *fullname = NULL;
1777
ret = asprintf(&fullname, "%s/%s", tempdir,
1783
ret = remove(fullname);
1785
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1792
ret = rmdir(tempdir);
1793
if(ret == -1 and errno != ENOENT){
3225
/* Cleans up the circular linked list of Mandos servers the client
3227
if(mc.current_server != NULL){
3228
mc.current_server->prev->next = NULL;
3229
while(mc.current_server != NULL){
3230
server *next = mc.current_server->next;
3232
#pragma GCC diagnostic push
3233
#pragma GCC diagnostic ignored "-Wcast-qual"
3235
free((char *)(mc.current_server->ip));
3237
#pragma GCC diagnostic pop
3239
free(mc.current_server);
3240
mc.current_server = next;
3244
/* Re-raise privileges */
3246
ret = raise_privileges();
3249
perror_plus("Failed to raise privileges");
3252
/* Run network hooks */
3253
run_network_hooks("stop", interfaces_hooks != NULL ?
3254
interfaces_hooks : "", delay);
3256
/* Take down the network interfaces which were brought up */
3258
char *interface = NULL;
3259
while((interface = argz_next(interfaces_to_take_down,
3260
interfaces_to_take_down_size,
3262
ret = take_down_interface(interface);
3265
perror_plus("Failed to take down interface");
3268
if(debug and (interfaces_to_take_down == NULL)){
3269
fprintf_plus(stderr, "No interfaces needed to be taken"
3275
ret = lower_privileges_permanently();
3278
perror_plus("Failed to lower privileges permanently");
3282
free(interfaces_to_take_down);
3283
free(interfaces_hooks);
3285
void clean_dir_at(int base, const char * const dirname,
3287
struct dirent **direntries = NULL;
3289
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3295
perror_plus("open");
3298
int numentries = scandirat(dir_fd, ".", &direntries,
3299
notdotentries, alphasort);
3300
if(numentries >= 0){
3301
for(int i = 0; i < numentries; i++){
3303
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3304
dirname, direntries[i]->d_name);
3306
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3308
if(errno == EISDIR){
3309
dret = unlinkat(dir_fd, direntries[i]->d_name,
3312
if((dret == -1) and (errno == ENOTEMPTY)
3313
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3314
== 0) and (level == 0)){
3315
/* Recurse only in this special case */
3316
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3319
if((dret == -1) and (errno != ENOENT)){
3320
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3321
direntries[i]->d_name, strerror(errno));
3324
free(direntries[i]);
3327
/* need to clean even if 0 because man page doesn't specify */
3329
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3330
if(dret == -1 and errno != ENOENT){
3331
perror_plus("rmdir");
3334
perror_plus("scandirat");
3339
/* Removes the GPGME temp directory and all files inside */
3340
if(tempdir != NULL){
3341
clean_dir_at(-1, tempdir, 0);