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- Committer: Teddy Hogeborn
- Date: 2011-02-27 17:00:41 UTC
- Revision ID: teddy@fukt.bsnet.se-20110227170041-2b7h5ftbexm1uotk
* debian/mandos-client.postrm (purge): Bug fix: update initramfs also
on purge.
* mandos (MultiprocessingMixInWithPipe.add_pipe): raise
NotImplementedError.
(string_to_delta): Don't use message attribute of exception.
on purge.
* mandos (MultiprocessingMixInWithPipe.add_pipe): raise
NotImplementedError.
(string_to_delta): Don't use message attribute of exception.
- files removed:
- debian/mandos-client.examples
- network-hooks.d
- files modified:
- .bzrignore
added
removed
plugins.d/mandos-client.c
9
9
* "browse_callback", and parts of "main".
10
10
*
11
11
* Everything else is
12
* Copyright © 2008-2012 Teddy Hogeborn
13
* Copyright © 2008-2012 Björn Påhlsson
12
* Copyright © 2008-2010 Teddy Hogeborn
13
* Copyright © 2008-2010 Björn Påhlsson
14
14
*
15
15
* This program is free software: you can redistribute it and/or
16
16
* modify it under the terms of the GNU General Public License as
26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
28
28
*
29
* Contact the authors at <mandos@recompile.se>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
30
*/
31
31
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
41
41
42
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
47
strtof(), abort() */
53
53
sockaddr_in6, PF_INET6,
54
54
SOCK_STREAM, uid_t, gid_t, open(),
55
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
56
#include <sys/stat.h> /* open() */
57
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
58
inet_pton(), connect() */
59
59
#include <fcntl.h> /* open() */
61
61
*/
62
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
63
strtoimax() */
64
#include <errno.h> /* perror(), errno,
65
program_invocation_short_name */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
66
#include <time.h> /* nanosleep(), time(), sleep() */
67
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
68
SIOCSIFFLAGS, if_indextoname(),
72
72
*/
73
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
74
getuid(), getgid(), seteuid(),
75
setgid(), pause(), _exit() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
75
setgid(), pause() */
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
77
#include <iso646.h> /* not, or, and */
78
78
#include <argp.h> /* struct argp_option, error_t, struct
79
79
argp_state, struct argp,
84
84
raise() */
85
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
87
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
88
WEXITSTATUS(), WTERMSIG() */
89
#include <grp.h> /* setgroups() */
90
#include <argz.h> /* argz_add_sep(), argz_next(),
91
argz_delete(), argz_append(),
92
argz_stringify(), argz_add(),
93
argz_count() */
94
87
95
88
#ifdef __linux__
96
89
#include <sys/klog.h> /* klogctl() */
114
107
init_gnutls_session(),
115
108
GNUTLS_* */
116
109
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
110
/* gnutls_certificate_set_openpgp_key_file(),
111
GNUTLS_OPENPGP_FMT_BASE64 */
119
112
120
113
/* GPGME */
121
114
#include <gpgme.h> /* All GPGME types, constants and
129
122
#define PATHDIR "/conf/conf.d/mandos"
130
123
#define SECKEY "seckey.txt"
131
124
#define PUBKEY "pubkey.txt"
132
#define HOOKDIR "/lib/mandos/network-hooks.d"
133
125
134
126
bool debug = false;
135
127
static const char mandos_protocol_version[] = "1";
136
128
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
138
130
static const char sys_class_net[] = "/sys/class/net";
139
131
char *connect_to = NULL;
140
const char *hookdir = HOOKDIR;
141
uid_t uid = 65534;
142
gid_t gid = 65534;
143
144
/* Doubly linked list that need to be circularly linked when used */
145
typedef struct server{
146
const char *ip;
147
in_port_t port;
148
AvahiIfIndex if_index;
149
int af;
150
struct timespec last_seen;
151
struct server *next;
152
struct server *prev;
153
} server;
154
132
155
133
/* Used for passing in values through the Avahi callback functions */
156
134
typedef struct {
135
AvahiSimplePoll *simple_poll;
157
136
AvahiServer *server;
158
137
gnutls_certificate_credentials_t cred;
159
138
unsigned int dh_bits;
160
139
gnutls_dh_params_t dh_params;
161
140
const char *priority;
162
141
gpgme_ctx_t ctx;
163
server *current_server;
164
char *interfaces;
165
size_t interfaces_size;
166
142
} mandos_context;
167
143
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
144
/* global context so signal handler can reach it*/
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
170
148
171
149
sig_atomic_t quit_now = 0;
172
150
int signal_received = 0;
173
151
174
/* Function to use when printing errors */
175
void perror_plus(const char *print_text){
176
int e = errno;
177
fprintf(stderr, "Mandos plugin %s: ",
178
program_invocation_short_name);
179
errno = e;
180
perror(print_text);
181
}
182
183
__attribute__((format (gnu_printf, 2, 3)))
184
int fprintf_plus(FILE *stream, const char *format, ...){
185
va_list ap;
186
va_start (ap, format);
187
188
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
program_invocation_short_name));
190
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
191
}
192
193
152
/*
194
153
* Make additional room in "buffer" for at least BUFFER_SIZE more
195
154
* bytes. "buffer_capacity" is how much is currently allocated,
196
155
* "buffer_length" is how much is already used.
197
156
*/
198
157
size_t incbuffer(char **buffer, size_t buffer_length,
199
size_t buffer_capacity){
158
size_t buffer_capacity){
200
159
if(buffer_length + BUFFER_SIZE > buffer_capacity){
201
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
202
161
if(buffer == NULL){
207
166
return buffer_capacity;
208
167
}
209
168
210
/* Add server to set of servers to retry periodically */
211
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
212
int af, server **current_server){
213
int ret;
214
server *new_server = malloc(sizeof(server));
215
if(new_server == NULL){
216
perror_plus("malloc");
217
return false;
218
}
219
*new_server = (server){ .ip = strdup(ip),
220
.port = port,
221
.if_index = if_index,
222
.af = af };
223
if(new_server->ip == NULL){
224
perror_plus("strdup");
225
return false;
226
}
227
/* Special case of first server */
228
if(*current_server == NULL){
229
new_server->next = new_server;
230
new_server->prev = new_server;
231
*current_server = new_server;
232
/* Place the new server last in the list */
233
} else {
234
new_server->next = *current_server;
235
new_server->prev = (*current_server)->prev;
236
new_server->prev->next = new_server;
237
(*current_server)->prev = new_server;
238
}
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
240
if(ret == -1){
241
perror_plus("clock_gettime");
242
return false;
243
}
244
return true;
245
}
246
247
169
/*
248
170
* Initialize GPGME.
249
171
*/
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
252
174
gpgme_error_t rc;
253
175
gpgme_engine_info_t engine_info;
254
176
177
255
178
/*
256
179
* Helper function to insert pub and seckey to the engine keyring.
257
180
*/
262
185
263
186
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
264
187
if(fd == -1){
265
perror_plus("open");
188
perror("open");
266
189
return false;
267
190
}
268
191
269
192
rc = gpgme_data_new_from_fd(&pgp_data, fd);
270
193
if(rc != GPG_ERR_NO_ERROR){
271
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
272
gpgme_strsource(rc), gpgme_strerror(rc));
194
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
273
196
return false;
274
197
}
275
198
276
rc = gpgme_op_import(mc->ctx, pgp_data);
199
rc = gpgme_op_import(mc.ctx, pgp_data);
277
200
if(rc != GPG_ERR_NO_ERROR){
278
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
gpgme_strsource(rc), gpgme_strerror(rc));
280
203
return false;
281
204
}
282
205
283
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
284
207
if(ret == -1){
285
perror_plus("close");
208
perror("close");
286
209
}
287
210
gpgme_data_release(pgp_data);
288
211
return true;
289
212
}
290
213
291
214
if(debug){
292
fprintf_plus(stderr, "Initializing GPGME\n");
215
fprintf(stderr, "Initializing GPGME\n");
293
216
}
294
217
295
218
/* Init GPGME */
296
219
gpgme_check_version(NULL);
297
220
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
298
221
if(rc != GPG_ERR_NO_ERROR){
299
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
301
224
return false;
302
225
}
303
226
304
/* Set GPGME home directory for the OpenPGP engine only */
227
/* Set GPGME home directory for the OpenPGP engine only */
305
228
rc = gpgme_get_engine_info(&engine_info);
306
229
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
309
232
return false;
310
233
}
311
234
while(engine_info != NULL){
317
240
engine_info = engine_info->next;
318
241
}
319
242
if(engine_info == NULL){
320
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
321
tempdir);
243
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
322
244
return false;
323
245
}
324
246
325
247
/* Create new GPGME "context" */
326
rc = gpgme_new(&(mc->ctx));
248
rc = gpgme_new(&(mc.ctx));
327
249
if(rc != GPG_ERR_NO_ERROR){
328
fprintf_plus(stderr, "Mandos plugin mandos-client: "
329
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
330
gpgme_strerror(rc));
250
fprintf(stderr, "bad gpgme_new: %s: %s\n",
251
gpgme_strsource(rc), gpgme_strerror(rc));
331
252
return false;
332
253
}
333
254
344
265
*/
345
266
static ssize_t pgp_packet_decrypt(const char *cryptotext,
346
267
size_t crypto_size,
347
char **plaintext,
348
mandos_context *mc){
268
char **plaintext){
349
269
gpgme_data_t dh_crypto, dh_plain;
350
270
gpgme_error_t rc;
351
271
ssize_t ret;
353
273
ssize_t plaintext_length = 0;
354
274
355
275
if(debug){
356
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
357
277
}
358
278
359
279
/* Create new GPGME data buffer from memory cryptotext */
360
280
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
361
281
0);
362
282
if(rc != GPG_ERR_NO_ERROR){
363
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
364
gpgme_strsource(rc), gpgme_strerror(rc));
283
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
284
gpgme_strsource(rc), gpgme_strerror(rc));
365
285
return -1;
366
286
}
367
287
368
288
/* Create new empty GPGME data buffer for the plaintext */
369
289
rc = gpgme_data_new(&dh_plain);
370
290
if(rc != GPG_ERR_NO_ERROR){
371
fprintf_plus(stderr, "Mandos plugin mandos-client: "
372
"bad gpgme_data_new: %s: %s\n",
373
gpgme_strsource(rc), gpgme_strerror(rc));
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
374
293
gpgme_data_release(dh_crypto);
375
294
return -1;
376
295
}
377
296
378
297
/* Decrypt data from the cryptotext data buffer to the plaintext
379
298
data buffer */
380
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
381
300
if(rc != GPG_ERR_NO_ERROR){
382
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
383
gpgme_strsource(rc), gpgme_strerror(rc));
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
384
303
plaintext_length = -1;
385
304
if(debug){
386
305
gpgme_decrypt_result_t result;
387
result = gpgme_op_decrypt_result(mc->ctx);
306
result = gpgme_op_decrypt_result(mc.ctx);
388
307
if(result == NULL){
389
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
390
309
} else {
391
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
392
result->unsupported_algorithm);
393
fprintf_plus(stderr, "Wrong key usage: %u\n",
394
result->wrong_key_usage);
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
395
314
if(result->file_name != NULL){
396
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
fprintf(stderr, "File name: %s\n", result->file_name);
397
316
}
398
317
gpgme_recipient_t recipient;
399
318
recipient = result->recipients;
400
319
while(recipient != NULL){
401
fprintf_plus(stderr, "Public key algorithm: %s\n",
402
gpgme_pubkey_algo_name
403
(recipient->pubkey_algo));
404
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
405
fprintf_plus(stderr, "Secret key available: %s\n",
406
recipient->status == GPG_ERR_NO_SECKEY
407
? "No" : "Yes");
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
325
? "No" : "Yes");
408
326
recipient = recipient->next;
409
327
}
410
328
}
413
331
}
414
332
415
333
if(debug){
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
334
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
417
335
}
418
336
419
337
/* Seek back to the beginning of the GPGME plaintext data buffer */
420
338
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
421
perror_plus("gpgme_data_seek");
339
perror("gpgme_data_seek");
422
340
plaintext_length = -1;
423
341
goto decrypt_end;
424
342
}
426
344
*plaintext = NULL;
427
345
while(true){
428
346
plaintext_capacity = incbuffer(plaintext,
429
(size_t)plaintext_length,
430
plaintext_capacity);
347
(size_t)plaintext_length,
348
plaintext_capacity);
431
349
if(plaintext_capacity == 0){
432
perror_plus("incbuffer");
433
plaintext_length = -1;
434
goto decrypt_end;
350
perror("incbuffer");
351
plaintext_length = -1;
352
goto decrypt_end;
435
353
}
436
354
437
355
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
442
360
break;
443
361
}
444
362
if(ret < 0){
445
perror_plus("gpgme_data_read");
363
perror("gpgme_data_read");
446
364
plaintext_length = -1;
447
365
goto decrypt_end;
448
366
}
450
368
}
451
369
452
370
if(debug){
453
fprintf_plus(stderr, "Decrypted password is: ");
371
fprintf(stderr, "Decrypted password is: ");
454
372
for(ssize_t i = 0; i < plaintext_length; i++){
455
373
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
456
374
}
468
386
}
469
387
470
388
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
389
const char *ret = gnutls_strerror(value); /* Spurious warning from
390
-Wunreachable-code */
472
391
if(ret == NULL)
473
392
ret = "(unknown)";
474
393
return ret;
477
396
/* GnuTLS log function callback */
478
397
static void debuggnutls(__attribute__((unused)) int level,
479
398
const char* string){
480
fprintf_plus(stderr, "GnuTLS: %s", string);
399
fprintf(stderr, "GnuTLS: %s", string);
481
400
}
482
401
483
402
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename,
485
mandos_context *mc){
403
const char *seckeyfilename){
486
404
int ret;
487
405
488
406
if(debug){
489
fprintf_plus(stderr, "Initializing GnuTLS\n");
407
fprintf(stderr, "Initializing GnuTLS\n");
490
408
}
491
409
492
410
ret = gnutls_global_init();
493
411
if(ret != GNUTLS_E_SUCCESS){
494
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
495
safer_gnutls_strerror(ret));
412
fprintf(stderr, "GnuTLS global_init: %s\n",
413
safer_gnutls_strerror(ret));
496
414
return -1;
497
415
}
498
416
505
423
}
506
424
507
425
/* OpenPGP credentials */
508
ret = gnutls_certificate_allocate_credentials(&mc->cred);
426
gnutls_certificate_allocate_credentials(&mc.cred);
509
427
if(ret != GNUTLS_E_SUCCESS){
510
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
511
safer_gnutls_strerror(ret));
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
429
from
430
-Wunreachable-code
431
*/
432
safer_gnutls_strerror(ret));
512
433
gnutls_global_deinit();
513
434
return -1;
514
435
}
515
436
516
437
if(debug){
517
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
518
" secret key %s as GnuTLS credentials\n",
519
pubkeyfilename,
520
seckeyfilename);
438
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
439
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
440
seckeyfilename);
521
441
}
522
442
523
443
ret = gnutls_certificate_set_openpgp_key_file
524
(mc->cred, pubkeyfilename, seckeyfilename,
444
(mc.cred, pubkeyfilename, seckeyfilename,
525
445
GNUTLS_OPENPGP_FMT_BASE64);
526
446
if(ret != GNUTLS_E_SUCCESS){
527
fprintf_plus(stderr,
528
"Error[%d] while reading the OpenPGP key pair ('%s',"
529
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
530
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
531
safer_gnutls_strerror(ret));
447
fprintf(stderr,
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));
532
452
goto globalfail;
533
453
}
534
454
535
455
/* GnuTLS server initialization */
536
ret = gnutls_dh_params_init(&mc->dh_params);
456
ret = gnutls_dh_params_init(&mc.dh_params);
537
457
if(ret != GNUTLS_E_SUCCESS){
538
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
539
" initialization: %s\n",
540
safer_gnutls_strerror(ret));
458
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
459
" %s\n", safer_gnutls_strerror(ret));
541
460
goto globalfail;
542
461
}
543
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
462
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
544
463
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
546
safer_gnutls_strerror(ret));
464
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
465
safer_gnutls_strerror(ret));
547
466
goto globalfail;
548
467
}
549
468
550
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
469
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
551
470
552
471
return 0;
553
472
554
473
globalfail:
555
474
556
gnutls_certificate_free_credentials(mc->cred);
475
gnutls_certificate_free_credentials(mc.cred);
557
476
gnutls_global_deinit();
558
gnutls_dh_params_deinit(mc->dh_params);
477
gnutls_dh_params_deinit(mc.dh_params);
559
478
return -1;
560
479
}
561
480
562
static int init_gnutls_session(gnutls_session_t *session,
563
mandos_context *mc){
481
static int init_gnutls_session(gnutls_session_t *session){
564
482
int ret;
565
483
/* GnuTLS session creation */
566
484
do {
570
488
}
571
489
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
572
490
if(ret != GNUTLS_E_SUCCESS){
573
fprintf_plus(stderr,
574
"Error in GnuTLS session initialization: %s\n",
575
safer_gnutls_strerror(ret));
491
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
492
safer_gnutls_strerror(ret));
576
493
}
577
494
578
495
{
579
496
const char *err;
580
497
do {
581
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
498
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
582
499
if(quit_now){
583
500
gnutls_deinit(*session);
584
501
return -1;
585
502
}
586
503
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
587
504
if(ret != GNUTLS_E_SUCCESS){
588
fprintf_plus(stderr, "Syntax error at: %s\n", err);
589
fprintf_plus(stderr, "GnuTLS error: %s\n",
590
safer_gnutls_strerror(ret));
505
fprintf(stderr, "Syntax error at: %s\n", err);
506
fprintf(stderr, "GnuTLS error: %s\n",
507
safer_gnutls_strerror(ret));
591
508
gnutls_deinit(*session);
592
509
return -1;
593
510
}
595
512
596
513
do {
597
514
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
598
mc->cred);
515
mc.cred);
599
516
if(quit_now){
600
517
gnutls_deinit(*session);
601
518
return -1;
602
519
}
603
520
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
604
521
if(ret != GNUTLS_E_SUCCESS){
605
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
606
safer_gnutls_strerror(ret));
522
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
523
safer_gnutls_strerror(ret));
607
524
gnutls_deinit(*session);
608
525
return -1;
609
526
}
611
528
/* ignore client certificate if any. */
612
529
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
613
530
614
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
531
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
615
532
616
533
return 0;
617
534
}
621
538
__attribute__((unused)) const char *txt){}
622
539
623
540
/* Called when a Mandos server is found */
624
static int start_mandos_communication(const char *ip, in_port_t port,
541
static int start_mandos_communication(const char *ip, uint16_t port,
625
542
AvahiIfIndex if_index,
626
int af, mandos_context *mc){
543
int af){
627
544
int ret, tcp_sd = -1;
628
545
ssize_t sret;
629
546
union {
654
571
pf = PF_INET;
655
572
break;
656
573
default:
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
574
fprintf(stderr, "Bad address family: %d\n", af);
658
575
errno = EINVAL;
659
576
return -1;
660
577
}
661
578
662
/* If the interface is specified and we have a list of interfaces */
663
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
664
/* Check if the interface is one of the interfaces we are using */
665
bool match = false;
666
{
667
char *interface = NULL;
668
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
669
interface))){
670
if(if_nametoindex(interface) == (unsigned int)if_index){
671
match = true;
672
break;
673
}
674
}
675
}
676
if(not match){
677
/* This interface does not match any in the list, so we don't
678
connect to the server */
679
if(debug){
680
char interface[IF_NAMESIZE];
681
if(if_indextoname((unsigned int)if_index, interface) == NULL){
682
perror_plus("if_indextoname");
683
} else {
684
fprintf_plus(stderr, "Skipping server on non-used interface"
685
" \"%s\"\n",
686
if_indextoname((unsigned int)if_index,
687
interface));
688
}
689
}
690
return -1;
691
}
692
}
693
694
ret = init_gnutls_session(&session, mc);
579
ret = init_gnutls_session(&session);
695
580
if(ret != 0){
696
581
return -1;
697
582
}
698
583
699
584
if(debug){
700
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
585
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
586
"\n", ip, port);
702
587
}
703
588
704
589
tcp_sd = socket(pf, SOCK_STREAM, 0);
705
590
if(tcp_sd < 0){
706
591
int e = errno;
707
perror_plus("socket");
592
perror("socket");
708
593
errno = e;
709
594
goto mandos_end;
710
595
}
724
609
}
725
610
if(ret < 0 ){
726
611
int e = errno;
727
perror_plus("inet_pton");
612
perror("inet_pton");
728
613
errno = e;
729
614
goto mandos_end;
730
615
}
731
616
if(ret == 0){
732
617
int e = errno;
733
fprintf_plus(stderr, "Bad address: %s\n", ip);
618
fprintf(stderr, "Bad address: %s\n", ip);
734
619
errno = e;
735
620
goto mandos_end;
736
621
}
737
622
if(af == AF_INET6){
738
to.in6.sin6_port = htons(port);
623
to.in6.sin6_port = htons(port); /* Spurious warnings from
624
-Wconversion and
625
-Wunreachable-code */
626
739
627
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
740
628
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
741
-Wunreachable-code*/
629
-Wunreachable-code*/
742
630
if(if_index == AVAHI_IF_UNSPEC){
743
fprintf_plus(stderr, "An IPv6 link-local address is"
744
" incomplete without a network interface\n");
631
fprintf(stderr, "An IPv6 link-local address is incomplete"
632
" without a network interface\n");
745
633
errno = EINVAL;
746
634
goto mandos_end;
747
635
}
763
651
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
764
652
char interface[IF_NAMESIZE];
765
653
if(if_indextoname((unsigned int)if_index, interface) == NULL){
766
perror_plus("if_indextoname");
654
perror("if_indextoname");
767
655
} else {
768
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
769
"\n", ip, interface, (uintmax_t)port);
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
770
658
}
771
659
} else {
772
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
773
ip, (uintmax_t)port);
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
661
port);
774
662
}
775
663
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
776
664
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
783
671
sizeof(addrstr));
784
672
}
785
673
if(pcret == NULL){
786
perror_plus("inet_ntop");
674
perror("inet_ntop");
787
675
} else {
788
676
if(strcmp(addrstr, ip) != 0){
789
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
677
fprintf(stderr, "Canonical address form: %s\n", addrstr);
790
678
}
791
679
}
792
680
}
804
692
if(ret < 0){
805
693
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
806
694
int e = errno;
807
perror_plus("connect");
695
perror("connect");
808
696
errno = e;
809
697
}
810
698
goto mandos_end;
820
708
while(true){
821
709
size_t out_size = strlen(out);
822
710
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
823
out_size - written));
711
out_size - written));
824
712
if(ret == -1){
825
713
int e = errno;
826
perror_plus("write");
714
perror("write");
827
715
errno = e;
828
716
goto mandos_end;
829
717
}
846
734
}
847
735
848
736
if(debug){
849
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
737
fprintf(stderr, "Establishing TLS session with %s\n", ip);
850
738
}
851
739
852
740
if(quit_now){
854
742
goto mandos_end;
855
743
}
856
744
857
/* This casting via intptr_t is to eliminate warning about casting
858
an int to a pointer type. This is exactly how the GnuTLS Guile
859
function "set-session-transport-fd!" does it. */
860
gnutls_transport_set_ptr(session,
861
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
745
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
862
746
863
747
if(quit_now){
864
748
errno = EINTR;
875
759
876
760
if(ret != GNUTLS_E_SUCCESS){
877
761
if(debug){
878
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
762
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
879
763
gnutls_perror(ret);
880
764
}
881
765
errno = EPROTO;
885
769
/* Read OpenPGP packet that contains the wanted password */
886
770
887
771
if(debug){
888
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
889
" %s\n", ip);
772
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
773
ip);
890
774
}
891
775
892
776
while(true){
897
781
}
898
782
899
783
buffer_capacity = incbuffer(&buffer, buffer_length,
900
buffer_capacity);
784
buffer_capacity);
901
785
if(buffer_capacity == 0){
902
786
int e = errno;
903
perror_plus("incbuffer");
787
perror("incbuffer");
904
788
errno = e;
905
789
goto mandos_end;
906
790
}
930
814
}
931
815
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
932
816
if(ret < 0){
933
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
934
"***\n");
817
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
935
818
gnutls_perror(ret);
936
819
errno = EPROTO;
937
820
goto mandos_end;
938
821
}
939
822
break;
940
823
default:
941
fprintf_plus(stderr, "Unknown error while reading data from"
942
" encrypted session with Mandos server\n");
824
fprintf(stderr, "Unknown error while reading data from"
825
" encrypted session with Mandos server\n");
943
826
gnutls_bye(session, GNUTLS_SHUT_RDWR);
944
827
errno = EIO;
945
828
goto mandos_end;
950
833
}
951
834
952
835
if(debug){
953
fprintf_plus(stderr, "Closing TLS session\n");
836
fprintf(stderr, "Closing TLS session\n");
954
837
}
955
838
956
839
if(quit_now){
968
851
969
852
if(buffer_length > 0){
970
853
ssize_t decrypted_buffer_size;
971
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
972
&decrypted_buffer, mc);
854
decrypted_buffer_size = pgp_packet_decrypt(buffer,
855
buffer_length,
856
&decrypted_buffer);
973
857
if(decrypted_buffer_size >= 0){
974
858
975
859
written = 0;
985
869
if(ret == 0 and ferror(stdout)){
986
870
int e = errno;
987
871
if(debug){
988
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
989
strerror(errno));
872
fprintf(stderr, "Error writing encrypted data: %s\n",
873
strerror(errno));
990
874
}
991
875
errno = e;
992
876
goto mandos_end;
1011
895
if(e == 0){
1012
896
e = errno;
1013
897
}
1014
perror_plus("close");
898
perror("close");
1015
899
}
1016
900
gnutls_deinit(session);
1017
errno = e;
1018
901
if(quit_now){
1019
errno = EINTR;
902
e = EINTR;
1020
903
retval = -1;
1021
904
}
905
errno = e;
1022
906
}
1023
907
return retval;
1024
908
}
1036
920
AVAHI_GCC_UNUSED AvahiStringList *txt,
1037
921
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1038
922
flags,
1039
void* mc){
1040
if(r == NULL){
1041
return;
1042
}
923
AVAHI_GCC_UNUSED void* userdata){
924
assert(r);
1043
925
1044
926
/* Called whenever a service has been resolved successfully or
1045
927
timed out */
1051
933
switch(event){
1052
934
default:
1053
935
case AVAHI_RESOLVER_FAILURE:
1054
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1055
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1056
domain,
1057
avahi_strerror(avahi_server_errno
1058
(((mandos_context*)mc)->server)));
936
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
937
" of type '%s' in domain '%s': %s\n", name, type, domain,
938
avahi_strerror(avahi_server_errno(mc.server)));
1059
939
break;
1060
940
1061
941
case AVAHI_RESOLVER_FOUND:
1063
943
char ip[AVAHI_ADDRESS_STR_MAX];
1064
944
avahi_address_snprint(ip, sizeof(ip), address);
1065
945
if(debug){
1066
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1067
PRIdMAX ") on port %" PRIu16 "\n", name,
1068
host_name, ip, (intmax_t)interface, port);
946
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
947
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
948
ip, (intmax_t)interface, port);
1069
949
}
1070
int ret = start_mandos_communication(ip, (in_port_t)port,
1071
interface,
1072
avahi_proto_to_af(proto),
1073
mc);
950
int ret = start_mandos_communication(ip, port, interface,
951
avahi_proto_to_af(proto));
1074
952
if(ret == 0){
1075
avahi_simple_poll_quit(simple_poll);
1076
} else {
1077
if(not add_server(ip, (in_port_t)port, interface,
1078
avahi_proto_to_af(proto),
1079
&((mandos_context*)mc)->current_server)){
1080
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1081
" list\n", name);
1082
}
953
avahi_simple_poll_quit(mc.simple_poll);
1083
954
}
1084
955
}
1085
956
}
1095
966
const char *domain,
1096
967
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1097
968
flags,
1098
void* mc){
1099
if(b == NULL){
1100
return;
1101
}
969
AVAHI_GCC_UNUSED void* userdata){
970
assert(b);
1102
971
1103
972
/* Called whenever a new services becomes available on the LAN or
1104
973
is removed from the LAN */
1111
980
default:
1112
981
case AVAHI_BROWSER_FAILURE:
1113
982
1114
fprintf_plus(stderr, "(Avahi browser) %s\n",
1115
avahi_strerror(avahi_server_errno
1116
(((mandos_context*)mc)->server)));
1117
avahi_simple_poll_quit(simple_poll);
983
fprintf(stderr, "(Avahi browser) %s\n",
984
avahi_strerror(avahi_server_errno(mc.server)));
985
avahi_simple_poll_quit(mc.simple_poll);
1118
986
return;
1119
987
1120
988
case AVAHI_BROWSER_NEW:
1123
991
the callback function is called the Avahi server will free the
1124
992
resolver for us. */
1125
993
1126
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1127
interface, protocol, name, type,
1128
domain, protocol, 0,
1129
resolve_callback, mc) == NULL)
1130
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1131
" %s\n", name,
1132
avahi_strerror(avahi_server_errno
1133
(((mandos_context*)mc)->server)));
994
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
995
name, type, domain, protocol, 0,
996
resolve_callback, NULL) == NULL)
997
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
998
name, avahi_strerror(avahi_server_errno(mc.server)));
1134
999
break;
1135
1000
1136
1001
case AVAHI_BROWSER_REMOVE:
1139
1004
case AVAHI_BROWSER_ALL_FOR_NOW:
1140
1005
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1141
1006
if(debug){
1142
fprintf_plus(stderr, "No Mandos server found, still"
1143
" searching...\n");
1007
fprintf(stderr, "No Mandos server found, still searching...\n");
1144
1008
}
1145
1009
break;
1146
1010
}
1147
1011
}
1148
1012
1149
/* Signal handler that stops main loop after SIGTERM */
1013
/* stop main loop after sigterm has been called */
1150
1014
static void handle_sigterm(int sig){
1151
1015
if(quit_now){
1152
1016
return;
1154
1018
quit_now = 1;
1155
1019
signal_received = sig;
1156
1020
int old_errno = errno;
1157
/* set main loop to exit */
1158
if(simple_poll != NULL){
1159
avahi_simple_poll_quit(simple_poll);
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1160
1023
}
1161
1024
errno = old_errno;
1162
1025
}
1163
1026
1164
bool get_flags(const char *ifname, struct ifreq *ifr){
1165
int ret;
1166
error_t ret_errno;
1167
1168
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1169
if(s < 0){
1170
ret_errno = errno;
1171
perror_plus("socket");
1172
errno = ret_errno;
1173
return false;
1174
}
1175
strcpy(ifr->ifr_name, ifname);
1176
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1177
if(ret == -1){
1178
if(debug){
1179
ret_errno = errno;
1180
perror_plus("ioctl SIOCGIFFLAGS");
1181
errno = ret_errno;
1182
}
1183
return false;
1184
}
1185
return true;
1186
}
1187
1188
bool good_flags(const char *ifname, const struct ifreq *ifr){
1189
1190
/* Reject the loopback device */
1191
if(ifr->ifr_flags & IFF_LOOPBACK){
1192
if(debug){
1193
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1194
ifname);
1195
}
1196
return false;
1197
}
1198
/* Accept point-to-point devices only if connect_to is specified */
1199
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1200
if(debug){
1201
fprintf_plus(stderr, "Accepting point-to-point interface"
1202
" \"%s\"\n", ifname);
1203
}
1204
return true;
1205
}
1206
/* Otherwise, reject non-broadcast-capable devices */
1207
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1208
if(debug){
1209
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1210
" \"%s\"\n", ifname);
1211
}
1212
return false;
1213
}
1214
/* Reject non-ARP interfaces (including dummy interfaces) */
1215
if(ifr->ifr_flags & IFF_NOARP){
1216
if(debug){
1217
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1218
ifname);
1219
}
1220
return false;
1221
}
1222
1223
/* Accept this device */
1224
if(debug){
1225
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1226
}
1227
return true;
1228
}
1229
1230
1027
/*
1231
1028
* This function determines if a directory entry in /sys/class/net
1232
1029
* corresponds to an acceptable network device.
1233
1030
* (This function is passed to scandir(3) as a filter function.)
1234
1031
*/
1235
1032
int good_interface(const struct dirent *if_entry){
1033
ssize_t ssret;
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1036
if_entry->d_name);
1037
if(ret < 0){
1038
perror("asprintf");
1039
return 0;
1040
}
1236
1041
if(if_entry->d_name[0] == '.'){
1237
1042
return 0;
1238
1043
}
1239
1240
struct ifreq ifr;
1241
if(not get_flags(if_entry->d_name, &ifr)){
1242
if(debug){
1243
fprintf_plus(stderr, "Failed to get flags for interface "
1244
"\"%s\"\n", if_entry->d_name);
1245
}
1246
return 0;
1247
}
1248
1249
if(not good_flags(if_entry->d_name, &ifr)){
1250
return 0;
1251
}
1252
return 1;
1253
}
1254
1255
/*
1256
* This function determines if a network interface is up.
1257
*/
1258
bool interface_is_up(const char *interface){
1259
struct ifreq ifr;
1260
if(not get_flags(interface, &ifr)){
1261
if(debug){
1262
fprintf_plus(stderr, "Failed to get flags for interface "
1263
"\"%s\"\n", interface);
1264
}
1265
return false;
1266
}
1267
1268
return (bool)(ifr.ifr_flags & IFF_UP);
1269
}
1270
1271
/*
1272
* This function determines if a network interface is running
1273
*/
1274
bool interface_is_running(const char *interface){
1275
struct ifreq ifr;
1276
if(not get_flags(interface, &ifr)){
1277
if(debug){
1278
fprintf_plus(stderr, "Failed to get flags for interface "
1279
"\"%s\"\n", interface);
1280
}
1281
return false;
1282
}
1283
1284
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1285
}
1286
1287
int notdotentries(const struct dirent *direntry){
1288
/* Skip "." and ".." */
1289
if(direntry->d_name[0] == '.'
1290
and (direntry->d_name[1] == '\0'
1291
or (direntry->d_name[1] == '.'
1292
and direntry->d_name[2] == '\0'))){
1293
return 0;
1294
}
1295
return 1;
1296
}
1297
1298
/* Is this directory entry a runnable program? */
1299
int runnable_hook(const struct dirent *direntry){
1300
int ret;
1301
size_t sret;
1302
struct stat st;
1303
1304
if((direntry->d_name)[0] == '\0'){
1305
/* Empty name? */
1306
return 0;
1307
}
1308
1309
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1310
"abcdefghijklmnopqrstuvwxyz"
1311
"0123456789"
1312
"_-");
1313
if((direntry->d_name)[sret] != '\0'){
1314
/* Contains non-allowed characters */
1315
if(debug){
1316
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1317
direntry->d_name);
1318
}
1319
return 0;
1320
}
1321
1322
char *fullname = NULL;
1323
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1324
if(ret < 0){
1325
perror_plus("asprintf");
1326
return 0;
1327
}
1328
1329
ret = stat(fullname, &st);
1330
if(ret == -1){
1331
if(debug){
1332
perror_plus("Could not stat hook");
1333
}
1334
return 0;
1335
}
1336
if(not (S_ISREG(st.st_mode))){
1337
/* Not a regular file */
1338
if(debug){
1339
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1340
direntry->d_name);
1341
}
1342
return 0;
1343
}
1344
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1345
/* Not executable */
1346
if(debug){
1347
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1348
direntry->d_name);
1349
}
1350
return 0;
1351
}
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1045
if(flags_fd == -1){
1046
perror("open");
1047
return 0;
1048
}
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){
1055
perror("malloc");
1056
close(flags_fd);
1057
return 0;
1058
}
1059
while(to_read > 0){
1060
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1061
(size_t)to_read));
1062
if(ssret == -1){
1063
perror("read");
1064
free(flagstring);
1065
close(flags_fd);
1066
return 0;
1067
}
1068
to_read -= ssret;
1069
if(ssret == 0){
1070
break;
1071
}
1072
}
1073
close(flags_fd);
1074
intmax_t tmpmax;
1075
char *tmp;
1076
errno = 0;
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){
1081
if(debug){
1082
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1083
flagstring, if_entry->d_name);
1084
}
1085
free(flagstring);
1086
return 0;
1087
}
1088
free(flagstring);
1089
ifreq_flags flags = (ifreq_flags)tmpmax;
1090
/* Reject the loopback device */
1091
if(flags & IFF_LOOPBACK){
1092
if(debug){
1093
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1094
if_entry->d_name);
1095
}
1096
return 0;
1097
}
1098
/* Accept point-to-point devices only if connect_to is specified */
1099
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1100
if(debug){
1101
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1102
if_entry->d_name);
1103
}
1104
return 1;
1105
}
1106
/* Otherwise, reject non-broadcast-capable devices */
1107
if(not (flags & IFF_BROADCAST)){
1108
if(debug){
1109
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1110
if_entry->d_name);
1111
}
1112
return 0;
1113
}
1114
/* Accept this device */
1352
1115
if(debug){
1353
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1354
direntry->d_name);
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1117
if_entry->d_name);
1355
1118
}
1356
1119
return 1;
1357
1120
}
1358
1121
1359
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1360
mandos_context *mc){
1361
int ret;
1362
struct timespec now;
1363
struct timespec waited_time;
1364
intmax_t block_time;
1365
1366
while(true){
1367
if(mc->current_server == NULL){
1368
if (debug){
1369
fprintf_plus(stderr, "Wait until first server is found."
1370
" No timeout!\n");
1371
}
1372
ret = avahi_simple_poll_iterate(s, -1);
1373
} else {
1374
if (debug){
1375
fprintf_plus(stderr, "Check current_server if we should run"
1376
" it, or wait\n");
1377
}
1378
/* the current time */
1379
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1380
if(ret == -1){
1381
perror_plus("clock_gettime");
1382
return -1;
1383
}
1384
/* Calculating in ms how long time between now and server
1385
who we visted longest time ago. Now - last seen. */
1386
waited_time.tv_sec = (now.tv_sec
1387
- mc->current_server->last_seen.tv_sec);
1388
waited_time.tv_nsec = (now.tv_nsec
1389
- mc->current_server->last_seen.tv_nsec);
1390
/* total time is 10s/10,000ms.
1391
Converting to s from ms by dividing by 1,000,
1392
and ns to ms by dividing by 1,000,000. */
1393
block_time = ((retry_interval
1394
- ((intmax_t)waited_time.tv_sec * 1000))
1395
- ((intmax_t)waited_time.tv_nsec / 1000000));
1396
1397
if (debug){
1398
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1399
block_time);
1400
}
1401
1402
if(block_time <= 0){
1403
ret = start_mandos_communication(mc->current_server->ip,
1404
mc->current_server->port,
1405
mc->current_server->if_index,
1406
mc->current_server->af, mc);
1407
if(ret == 0){
1408
avahi_simple_poll_quit(s);
1409
return 0;
1410
}
1411
ret = clock_gettime(CLOCK_MONOTONIC,
1412
&mc->current_server->last_seen);
1413
if(ret == -1){
1414
perror_plus("clock_gettime");
1415
return -1;
1416
}
1417
mc->current_server = mc->current_server->next;
1418
block_time = 0; /* Call avahi to find new Mandos
1419
servers, but don't block */
1420
}
1421
1422
ret = avahi_simple_poll_iterate(s, (int)block_time);
1423
}
1424
if(ret != 0){
1425
if (ret > 0 or errno != EINTR){
1426
return (ret != 1) ? ret : 0;
1427
}
1428
}
1429
}
1430
}
1431
1432
/* Set effective uid to 0, return errno */
1433
error_t raise_privileges(void){
1434
error_t old_errno = errno;
1435
error_t ret_errno = 0;
1436
if(seteuid(0) == -1){
1437
ret_errno = errno;
1438
perror_plus("seteuid");
1439
}
1440
errno = old_errno;
1441
return ret_errno;
1442
}
1443
1444
/* Set effective and real user ID to 0. Return errno. */
1445
error_t raise_privileges_permanently(void){
1446
error_t old_errno = errno;
1447
error_t ret_errno = raise_privileges();
1448
if(ret_errno != 0){
1449
errno = old_errno;
1450
return ret_errno;
1451
}
1452
if(setuid(0) == -1){
1453
ret_errno = errno;
1454
perror_plus("seteuid");
1455
}
1456
errno = old_errno;
1457
return ret_errno;
1458
}
1459
1460
/* Set effective user ID to unprivileged saved user ID */
1461
error_t lower_privileges(void){
1462
error_t old_errno = errno;
1463
error_t ret_errno = 0;
1464
if(seteuid(uid) == -1){
1465
ret_errno = errno;
1466
perror_plus("seteuid");
1467
}
1468
errno = old_errno;
1469
return ret_errno;
1470
}
1471
1472
/* Lower privileges permanently */
1473
error_t lower_privileges_permanently(void){
1474
error_t old_errno = errno;
1475
error_t ret_errno = 0;
1476
if(setuid(uid) == -1){
1477
ret_errno = errno;
1478
perror_plus("setuid");
1479
}
1480
errno = old_errno;
1481
return ret_errno;
1482
}
1483
1484
bool run_network_hooks(const char *mode, const char *interface,
1485
const float delay){
1486
struct dirent **direntries;
1487
struct dirent *direntry;
1488
int ret;
1489
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1490
alphasort);
1491
if(numhooks == -1){
1492
if(errno == ENOENT){
1493
if(debug){
1494
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1495
" found\n", hookdir);
1496
}
1497
} else {
1498
perror_plus("scandir");
1499
}
1500
} else {
1501
int devnull = open("/dev/null", O_RDONLY);
1502
for(int i = 0; i < numhooks; i++){
1503
direntry = direntries[i];
1504
char *fullname = NULL;
1505
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1506
if(ret < 0){
1507
perror_plus("asprintf");
1508
continue;
1509
}
1510
if(debug){
1511
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1512
direntry->d_name);
1513
}
1514
pid_t hook_pid = fork();
1515
if(hook_pid == 0){
1516
/* Child */
1517
/* Raise privileges */
1518
raise_privileges_permanently();
1519
/* Set group */
1520
errno = 0;
1521
ret = setgid(0);
1522
if(ret == -1){
1523
perror_plus("setgid");
1524
}
1525
/* Reset supplementary groups */
1526
errno = 0;
1527
ret = setgroups(0, NULL);
1528
if(ret == -1){
1529
perror_plus("setgroups");
1530
}
1531
dup2(devnull, STDIN_FILENO);
1532
close(devnull);
1533
dup2(STDERR_FILENO, STDOUT_FILENO);
1534
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1535
if(ret == -1){
1536
perror_plus("setenv");
1537
_exit(EX_OSERR);
1538
}
1539
ret = setenv("DEVICE", interface, 1);
1540
if(ret == -1){
1541
perror_plus("setenv");
1542
_exit(EX_OSERR);
1543
}
1544
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1545
if(ret == -1){
1546
perror_plus("setenv");
1547
_exit(EX_OSERR);
1548
}
1549
ret = setenv("MODE", mode, 1);
1550
if(ret == -1){
1551
perror_plus("setenv");
1552
_exit(EX_OSERR);
1553
}
1554
char *delaystring;
1555
ret = asprintf(&delaystring, "%f", delay);
1556
if(ret == -1){
1557
perror_plus("asprintf");
1558
_exit(EX_OSERR);
1559
}
1560
ret = setenv("DELAY", delaystring, 1);
1561
if(ret == -1){
1562
free(delaystring);
1563
perror_plus("setenv");
1564
_exit(EX_OSERR);
1565
}
1566
free(delaystring);
1567
if(connect_to != NULL){
1568
ret = setenv("CONNECT", connect_to, 1);
1569
if(ret == -1){
1570
perror_plus("setenv");
1571
_exit(EX_OSERR);
1572
}
1573
}
1574
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1575
perror_plus("execl");
1576
_exit(EXIT_FAILURE);
1577
}
1578
} else {
1579
int status;
1580
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1581
perror_plus("waitpid");
1582
free(fullname);
1583
continue;
1584
}
1585
if(WIFEXITED(status)){
1586
if(WEXITSTATUS(status) != 0){
1587
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1588
" with status %d\n", direntry->d_name,
1589
WEXITSTATUS(status));
1590
free(fullname);
1591
continue;
1592
}
1593
} else if(WIFSIGNALED(status)){
1594
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1595
" signal %d\n", direntry->d_name,
1596
WTERMSIG(status));
1597
free(fullname);
1598
continue;
1599
} else {
1600
fprintf_plus(stderr, "Warning: network hook \"%s\""
1601
" crashed\n", direntry->d_name);
1602
free(fullname);
1603
continue;
1604
}
1605
}
1606
free(fullname);
1607
if(debug){
1608
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1609
direntry->d_name);
1610
}
1611
}
1612
close(devnull);
1613
}
1614
return true;
1615
}
1616
1617
error_t bring_up_interface(const char *const interface,
1618
const float delay){
1619
int sd = -1;
1620
error_t old_errno = errno;
1621
error_t ret_errno = 0;
1622
int ret, ret_setflags;
1623
struct ifreq network;
1624
unsigned int if_index = if_nametoindex(interface);
1625
if(if_index == 0){
1626
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1627
errno = old_errno;
1628
return ENXIO;
1629
}
1630
1631
if(quit_now){
1632
errno = old_errno;
1633
return EINTR;
1634
}
1635
1636
if(not interface_is_up(interface)){
1637
if(not get_flags(interface, &network) and debug){
1638
ret_errno = errno;
1639
fprintf_plus(stderr, "Failed to get flags for interface "
1640
"\"%s\"\n", interface);
1641
return ret_errno;
1642
}
1643
network.ifr_flags |= IFF_UP;
1644
1645
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1646
if(sd < 0){
1647
ret_errno = errno;
1648
perror_plus("socket");
1649
errno = old_errno;
1650
return ret_errno;
1651
}
1652
1653
if(quit_now){
1654
close(sd);
1655
errno = old_errno;
1656
return EINTR;
1657
}
1658
1659
if(debug){
1660
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1661
interface);
1662
}
1663
1664
/* Raise priviliges */
1665
raise_privileges();
1666
1667
#ifdef __linux__
1668
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1669
messages about the network interface to mess up the prompt */
1670
int ret_linux = klogctl(8, NULL, 5);
1671
bool restore_loglevel = true;
1672
if(ret_linux == -1){
1673
restore_loglevel = false;
1674
perror_plus("klogctl");
1675
}
1676
#endif /* __linux__ */
1677
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1678
ret_errno = errno;
1679
#ifdef __linux__
1680
if(restore_loglevel){
1681
ret_linux = klogctl(7, NULL, 0);
1682
if(ret_linux == -1){
1683
perror_plus("klogctl");
1684
}
1685
}
1686
#endif /* __linux__ */
1687
1688
/* Lower privileges */
1689
lower_privileges();
1690
1691
/* Close the socket */
1692
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1693
if(ret == -1){
1694
perror_plus("close");
1695
}
1696
1697
if(ret_setflags == -1){
1698
errno = ret_errno;
1699
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1700
errno = old_errno;
1701
return ret_errno;
1702
}
1703
} else if(debug){
1704
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1705
interface);
1706
}
1707
1708
/* Sleep checking until interface is running.
1709
Check every 0.25s, up to total time of delay */
1710
for(int i=0; i < delay * 4; i++){
1711
if(interface_is_running(interface)){
1712
break;
1713
}
1714
struct timespec sleeptime = { .tv_nsec = 250000000 };
1715
ret = nanosleep(&sleeptime, NULL);
1716
if(ret == -1 and errno != EINTR){
1717
perror_plus("nanosleep");
1718
}
1719
}
1720
1721
errno = old_errno;
1722
return 0;
1723
}
1724
1725
error_t take_down_interface(const char *const interface){
1726
int sd = -1;
1727
error_t old_errno = errno;
1728
error_t ret_errno = 0;
1729
int ret, ret_setflags;
1730
struct ifreq network;
1731
unsigned int if_index = if_nametoindex(interface);
1732
if(if_index == 0){
1733
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1734
errno = old_errno;
1735
return ENXIO;
1736
}
1737
if(interface_is_up(interface)){
1738
if(not get_flags(interface, &network) and debug){
1739
ret_errno = errno;
1740
fprintf_plus(stderr, "Failed to get flags for interface "
1741
"\"%s\"\n", interface);
1742
return ret_errno;
1743
}
1744
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1745
1746
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1747
if(sd < 0){
1748
ret_errno = errno;
1749
perror_plus("socket");
1750
errno = old_errno;
1751
return ret_errno;
1752
}
1753
1754
if(debug){
1755
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1756
interface);
1757
}
1758
1759
/* Raise priviliges */
1760
raise_privileges();
1761
1762
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1763
ret_errno = errno;
1764
1765
/* Lower privileges */
1766
lower_privileges();
1767
1768
/* Close the socket */
1769
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1770
if(ret == -1){
1771
perror_plus("close");
1772
}
1773
1774
if(ret_setflags == -1){
1775
errno = ret_errno;
1776
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1777
errno = old_errno;
1778
return ret_errno;
1779
}
1780
} else if(debug){
1781
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1782
interface);
1783
}
1784
1785
errno = old_errno;
1786
return 0;
1787
}
1788
1789
1122
int main(int argc, char *argv[]){
1790
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1791
.priority = "SECURE256:!CTYPE-X.509:"
1792
"+CTYPE-OPENPGP", .current_server = NULL,
1793
.interfaces = NULL, .interfaces_size = 0 };
1794
1123
AvahiSServiceBrowser *sb = NULL;
1795
error_t ret_errno;
1124
int error;
1796
1125
int ret;
1797
1126
intmax_t tmpmax;
1798
1127
char *tmp;
1799
1128
int exitcode = EXIT_SUCCESS;
1800
char *interfaces_to_take_down = NULL;
1801
size_t interfaces_to_take_down_size = 0;
1129
const char *interface = "";
1130
struct ifreq network;
1131
int sd = -1;
1132
bool take_down_interface = false;
1133
uid_t uid;
1134
gid_t gid;
1802
1135
char tempdir[] = "/tmp/mandosXXXXXX";
1803
1136
bool tempdir_created = false;
1804
1137
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1805
1138
const char *seckey = PATHDIR "/" SECKEY;
1806
1139
const char *pubkey = PATHDIR "/" PUBKEY;
1807
char *interfaces_hooks = NULL;
1808
size_t interfaces_hooks_size = 0;
1809
1140
1810
1141
bool gnutls_initialized = false;
1811
1142
bool gpgme_initialized = false;
1812
1143
float delay = 2.5f;
1813
double retry_interval = 10; /* 10s between trying a server and
1814
retrying the same server again */
1815
1144
1816
1145
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1817
1146
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1823
1152
errno = 0;
1824
1153
ret = setgid(gid);
1825
1154
if(ret == -1){
1826
perror_plus("setgid");
1155
perror("setgid");
1827
1156
}
1828
1157
1829
1158
/* Lower user privileges (temporarily) */
1830
1159
errno = 0;
1831
1160
ret = seteuid(uid);
1832
1161
if(ret == -1){
1833
perror_plus("seteuid");
1162
perror("seteuid");
1834
1163
}
1835
1164
1836
1165
if(quit_now){
1871
1200
.arg = "SECONDS",
1872
1201
.doc = "Maximum delay to wait for interface startup",
1873
1202
.group = 2 },
1874
{ .name = "retry", .key = 132,
1875
.arg = "SECONDS",
1876
.doc = "Retry interval used when denied by the Mandos server",
1877
.group = 2 },
1878
{ .name = "network-hook-dir", .key = 133,
1879
.arg = "DIR",
1880
.doc = "Directory where network hooks are located",
1881
.group = 2 },
1882
1203
/*
1883
1204
* These reproduce what we would get without ARGP_NO_HELP
1884
1205
*/
1902
1223
connect_to = arg;
1903
1224
break;
1904
1225
case 'i': /* --interface */
1905
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1906
arg, (int)',');
1907
if(ret_errno != 0){
1908
argp_error(state, "%s", strerror(ret_errno));
1909
}
1226
interface = arg;
1910
1227
break;
1911
1228
case 's': /* --seckey */
1912
1229
seckey = arg;
1932
1249
if(errno != 0 or tmp == arg or *tmp != '\0'){
1933
1250
argp_error(state, "Bad delay");
1934
1251
}
1935
case 132: /* --retry */
1936
errno = 0;
1937
retry_interval = strtod(arg, &tmp);
1938
if(errno != 0 or tmp == arg or *tmp != '\0'
1939
or (retry_interval * 1000) > INT_MAX
1940
or retry_interval < 0){
1941
argp_error(state, "Bad retry interval");
1942
}
1943
break;
1944
case 133: /* --network-hook-dir */
1945
hookdir = arg;
1946
1252
break;
1947
1253
/*
1948
1254
* These reproduce what we would get without ARGP_NO_HELP
1955
1261
argp_state_help(state, state->out_stream,
1956
1262
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1957
1263
case 'V': /* --version */
1958
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1264
fprintf(state->out_stream, "%s\n", argp_program_version);
1959
1265
exit(argp_err_exit_status);
1960
1266
break;
1961
1267
default:
1976
1282
case ENOMEM:
1977
1283
default:
1978
1284
errno = ret;
1979
perror_plus("argp_parse");
1285
perror("argp_parse");
1980
1286
exitcode = EX_OSERR;
1981
1287
goto end;
1982
1288
case EINVAL:
1984
1290
goto end;
1985
1291
}
1986
1292
}
1987
1988
{
1989
/* Work around Debian bug #633582:
1990
<http://bugs.debian.org/633582> */
1991
1992
/* Re-raise priviliges */
1993
if(raise_privileges() == 0){
1994
struct stat st;
1995
1996
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1997
int seckey_fd = open(seckey, O_RDONLY);
1998
if(seckey_fd == -1){
1999
perror_plus("open");
2000
} else {
2001
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2002
if(ret == -1){
2003
perror_plus("fstat");
2004
} else {
2005
if(S_ISREG(st.st_mode)
2006
and st.st_uid == 0 and st.st_gid == 0){
2007
ret = fchown(seckey_fd, uid, gid);
2008
if(ret == -1){
2009
perror_plus("fchown");
2010
}
2011
}
2012
}
2013
TEMP_FAILURE_RETRY(close(seckey_fd));
2014
}
2015
}
2016
2017
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2018
int pubkey_fd = open(pubkey, O_RDONLY);
2019
if(pubkey_fd == -1){
2020
perror_plus("open");
2021
} else {
2022
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2023
if(ret == -1){
2024
perror_plus("fstat");
2025
} else {
2026
if(S_ISREG(st.st_mode)
2027
and st.st_uid == 0 and st.st_gid == 0){
2028
ret = fchown(pubkey_fd, uid, gid);
2029
if(ret == -1){
2030
perror_plus("fchown");
2031
}
2032
}
2033
}
2034
TEMP_FAILURE_RETRY(close(pubkey_fd));
2035
}
2036
}
2037
2038
/* Lower privileges */
2039
lower_privileges();
2040
}
2041
}
2042
2043
/* Remove invalid interface names (except "none") */
2044
{
2045
char *interface = NULL;
2046
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2047
interface))){
2048
if(strcmp(interface, "none") != 0
2049
and if_nametoindex(interface) == 0){
2050
if(interface[0] != '\0'){
2051
fprintf_plus(stderr, "Not using nonexisting interface"
2052
" \"%s\"\n", interface);
2053
}
2054
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2055
interface = NULL;
2056
}
2057
}
2058
}
2059
2060
/* Run network hooks */
2061
{
2062
if(mc.interfaces != NULL){
2063
interfaces_hooks = malloc(mc.interfaces_size);
2064
if(interfaces_hooks == NULL){
2065
perror_plus("malloc");
2066
goto end;
2067
}
2068
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2069
interfaces_hooks_size = mc.interfaces_size;
2070
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2071
(int)',');
2072
}
2073
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2074
interfaces_hooks : "", delay)){
2075
goto end;
2076
}
2077
}
2078
1293
2079
1294
if(not debug){
2080
1295
avahi_set_log_function(empty_log);
2081
1296
}
1297
1298
if(interface[0] == '\0'){
1299
struct dirent **direntries;
1300
ret = scandir(sys_class_net, &direntries, good_interface,
1301
alphasort);
1302
if(ret >= 1){
1303
/* Pick the first good interface */
1304
interface = strdup(direntries[0]->d_name);
1305
if(debug){
1306
fprintf(stderr, "Using interface \"%s\"\n", interface);
1307
}
1308
if(interface == NULL){
1309
perror("malloc");
1310
free(direntries);
1311
exitcode = EXIT_FAILURE;
1312
goto end;
1313
}
1314
free(direntries);
1315
} else {
1316
free(direntries);
1317
fprintf(stderr, "Could not find a network interface\n");
1318
exitcode = EXIT_FAILURE;
1319
goto end;
1320
}
1321
}
2082
1322
2083
1323
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2084
1324
from the signal handler */
2085
1325
/* Initialize the pseudo-RNG for Avahi */
2086
1326
srand((unsigned int) time(NULL));
2087
simple_poll = avahi_simple_poll_new();
2088
if(simple_poll == NULL){
2089
fprintf_plus(stderr,
2090
"Avahi: Failed to create simple poll object.\n");
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");
2091
1330
exitcode = EX_UNAVAILABLE;
2092
1331
goto end;
2093
1332
}
2095
1334
sigemptyset(&sigterm_action.sa_mask);
2096
1335
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2097
1336
if(ret == -1){
2098
perror_plus("sigaddset");
1337
perror("sigaddset");
2099
1338
exitcode = EX_OSERR;
2100
1339
goto end;
2101
1340
}
2102
1341
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2103
1342
if(ret == -1){
2104
perror_plus("sigaddset");
1343
perror("sigaddset");
2105
1344
exitcode = EX_OSERR;
2106
1345
goto end;
2107
1346
}
2108
1347
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2109
1348
if(ret == -1){
2110
perror_plus("sigaddset");
1349
perror("sigaddset");
2111
1350
exitcode = EX_OSERR;
2112
1351
goto end;
2113
1352
}
2117
1356
*/
2118
1357
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2119
1358
if(ret == -1){
2120
perror_plus("sigaction");
1359
perror("sigaction");
2121
1360
return EX_OSERR;
2122
1361
}
2123
1362
if(old_sigterm_action.sa_handler != SIG_IGN){
2124
1363
ret = sigaction(SIGINT, &sigterm_action, NULL);
2125
1364
if(ret == -1){
2126
perror_plus("sigaction");
1365
perror("sigaction");
2127
1366
exitcode = EX_OSERR;
2128
1367
goto end;
2129
1368
}
2130
1369
}
2131
1370
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2132
1371
if(ret == -1){
2133
perror_plus("sigaction");
1372
perror("sigaction");
2134
1373
return EX_OSERR;
2135
1374
}
2136
1375
if(old_sigterm_action.sa_handler != SIG_IGN){
2137
1376
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2138
1377
if(ret == -1){
2139
perror_plus("sigaction");
1378
perror("sigaction");
2140
1379
exitcode = EX_OSERR;
2141
1380
goto end;
2142
1381
}
2143
1382
}
2144
1383
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2145
1384
if(ret == -1){
2146
perror_plus("sigaction");
1385
perror("sigaction");
2147
1386
return EX_OSERR;
2148
1387
}
2149
1388
if(old_sigterm_action.sa_handler != SIG_IGN){
2150
1389
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2151
1390
if(ret == -1){
2152
perror_plus("sigaction");
2153
exitcode = EX_OSERR;
2154
goto end;
2155
}
2156
}
2157
2158
/* If no interfaces were specified, make a list */
2159
if(mc.interfaces == NULL){
2160
struct dirent **direntries;
2161
/* Look for any good interfaces */
2162
ret = scandir(sys_class_net, &direntries, good_interface,
2163
alphasort);
2164
if(ret >= 1){
2165
/* Add all found interfaces to interfaces list */
2166
for(int i = 0; i < ret; ++i){
2167
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2168
direntries[i]->d_name);
2169
if(ret_errno != 0){
2170
perror_plus("argz_add");
2171
continue;
2172
}
2173
if(debug){
2174
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2175
direntries[i]->d_name);
2176
}
2177
}
2178
free(direntries);
2179
} else {
2180
free(direntries);
2181
fprintf_plus(stderr, "Could not find a network interface\n");
2182
exitcode = EXIT_FAILURE;
2183
goto end;
2184
}
2185
}
2186
2187
/* Bring up interfaces which are down, and remove any "none"s */
2188
{
2189
char *interface = NULL;
2190
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2191
interface))){
2192
/* If interface name is "none", stop bringing up interfaces.
2193
Also remove all instances of "none" from the list */
2194
if(strcmp(interface, "none") == 0){
2195
argz_delete(&mc.interfaces, &mc.interfaces_size,
2196
interface);
2197
interface = NULL;
2198
while((interface = argz_next(mc.interfaces,
2199
mc.interfaces_size, interface))){
2200
if(strcmp(interface, "none") == 0){
2201
argz_delete(&mc.interfaces, &mc.interfaces_size,
2202
interface);
2203
interface = NULL;
1391
perror("sigaction");
1392
exitcode = EX_OSERR;
1393
goto end;
1394
}
1395
}
1396
1397
/* If the interface is down, bring it up */
1398
if(strcmp(interface, "none") != 0){
1399
if_index = (AvahiIfIndex) if_nametoindex(interface);
1400
if(if_index == 0){
1401
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1402
exitcode = EX_UNAVAILABLE;
1403
goto end;
1404
}
1405
1406
if(quit_now){
1407
goto end;
1408
}
1409
1410
/* Re-raise priviliges */
1411
errno = 0;
1412
ret = seteuid(0);
1413
if(ret == -1){
1414
perror("seteuid");
1415
}
1416
1417
#ifdef __linux__
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;
1422
if(ret == -1){
1423
restore_loglevel = false;
1424
perror("klogctl");
1425
}
1426
#endif /* __linux__ */
1427
1428
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1429
if(sd < 0){
1430
perror("socket");
1431
exitcode = EX_OSERR;
1432
#ifdef __linux__
1433
if(restore_loglevel){
1434
ret = klogctl(7, NULL, 0);
1435
if(ret == -1){
1436
perror("klogctl");
1437
}
1438
}
1439
#endif /* __linux__ */
1440
/* Lower privileges */
1441
errno = 0;
1442
ret = seteuid(uid);
1443
if(ret == -1){
1444
perror("seteuid");
1445
}
1446
goto end;
1447
}
1448
strcpy(network.ifr_name, interface);
1449
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1450
if(ret == -1){
1451
perror("ioctl SIOCGIFFLAGS");
1452
#ifdef __linux__
1453
if(restore_loglevel){
1454
ret = klogctl(7, NULL, 0);
1455
if(ret == -1){
1456
perror("klogctl");
1457
}
1458
}
1459
#endif /* __linux__ */
1460
exitcode = EX_OSERR;
1461
/* Lower privileges */
1462
errno = 0;
1463
ret = seteuid(uid);
1464
if(ret == -1){
1465
perror("seteuid");
1466
}
1467
goto end;
1468
}
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);
1473
if(ret == -1){
1474
take_down_interface = false;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1476
exitcode = EX_OSERR;
1477
#ifdef __linux__
1478
if(restore_loglevel){
1479
ret = klogctl(7, NULL, 0);
1480
if(ret == -1){
1481
perror("klogctl");
2204
1482
}
2205
1483
}
1484
#endif /* __linux__ */
1485
/* Lower privileges */
1486
errno = 0;
1487
ret = seteuid(uid);
1488
if(ret == -1){
1489
perror("seteuid");
1490
}
1491
goto end;
1492
}
1493
}
1494
/* sleep checking until interface is running */
1495
for(int i=0; i < delay * 4; i++){
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1497
if(ret == -1){
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_RUNNING){
2206
1500
break;
2207
1501
}
2208
bool interface_was_up = interface_is_up(interface);
2209
ret = bring_up_interface(interface, delay);
2210
if(not interface_was_up){
2211
if(ret != 0){
2212
errno = ret;
2213
perror_plus("Failed to bring up interface");
2214
} else {
2215
ret_errno = argz_add(&interfaces_to_take_down,
2216
&interfaces_to_take_down_size,
2217
interface);
2218
}
2219
}
2220
}
2221
if(debug and (interfaces_to_take_down == NULL)){
2222
fprintf_plus(stderr, "No interfaces were brought up\n");
2223
}
2224
}
2225
2226
/* If we only got one interface, explicitly use only that one */
2227
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2228
if(debug){
2229
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2230
mc.interfaces);
2231
}
2232
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1502
struct timespec sleeptime = { .tv_nsec = 250000000 };
1503
ret = nanosleep(&sleeptime, NULL);
1504
if(ret == -1 and errno != EINTR){
1505
perror("nanosleep");
1506
}
1507
}
1508
if(not take_down_interface){
1509
/* We won't need the socket anymore */
1510
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1511
if(ret == -1){
1512
perror("close");
1513
}
1514
}
1515
#ifdef __linux__
1516
if(restore_loglevel){
1517
/* Restores kernel loglevel to default */
1518
ret = klogctl(7, NULL, 0);
1519
if(ret == -1){
1520
perror("klogctl");
1521
}
1522
}
1523
#endif /* __linux__ */
1524
/* Lower privileges */
1525
errno = 0;
1526
if(take_down_interface){
1527
/* Lower privileges */
1528
ret = seteuid(uid);
1529
if(ret == -1){
1530
perror("seteuid");
1531
}
1532
} else {
1533
/* Lower privileges permanently */
1534
ret = setuid(uid);
1535
if(ret == -1){
1536
perror("setuid");
1537
}
1538
}
2233
1539
}
2234
1540
2235
1541
if(quit_now){
2236
1542
goto end;
2237
1543
}
2238
1544
2239
ret = init_gnutls_global(pubkey, seckey, &mc);
1545
ret = init_gnutls_global(pubkey, seckey);
2240
1546
if(ret == -1){
2241
fprintf_plus(stderr, "init_gnutls_global failed\n");
1547
fprintf(stderr, "init_gnutls_global failed\n");
2242
1548
exitcode = EX_UNAVAILABLE;
2243
1549
goto end;
2244
1550
} else {
2249
1555
goto end;
2250
1556
}
2251
1557
1558
tempdir_created = true;
2252
1559
if(mkdtemp(tempdir) == NULL){
2253
perror_plus("mkdtemp");
1560
tempdir_created = false;
1561
perror("mkdtemp");
2254
1562
goto end;
2255
1563
}
2256
tempdir_created = true;
2257
1564
2258
1565
if(quit_now){
2259
1566
goto end;
2260
1567
}
2261
1568
2262
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2263
fprintf_plus(stderr, "init_gpgme failed\n");
1569
if(not init_gpgme(pubkey, seckey, tempdir)){
1570
fprintf(stderr, "init_gpgme failed\n");
2264
1571
exitcode = EX_UNAVAILABLE;
2265
1572
goto end;
2266
1573
} else {
2275
1582
/* Connect directly, do not use Zeroconf */
2276
1583
/* (Mainly meant for debugging) */
2277
1584
char *address = strrchr(connect_to, ':');
2278
2279
1585
if(address == NULL){
2280
fprintf_plus(stderr, "No colon in address\n");
1586
fprintf(stderr, "No colon in address\n");
2281
1587
exitcode = EX_USAGE;
2282
1588
goto end;
2283
1589
}
2286
1592
goto end;
2287
1593
}
2288
1594
2289
in_port_t port;
1595
uint16_t port;
2290
1596
errno = 0;
2291
1597
tmpmax = strtoimax(address+1, &tmp, 10);
2292
1598
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2293
or tmpmax != (in_port_t)tmpmax){
2294
fprintf_plus(stderr, "Bad port number\n");
1599
or tmpmax != (uint16_t)tmpmax){
1600
fprintf(stderr, "Bad port number\n");
2295
1601
exitcode = EX_USAGE;
2296
1602
goto end;
2297
1603
}
2298
1604
2299
1605
if(quit_now){
2300
1606
goto end;
2301
1607
}
2302
1608
2303
port = (in_port_t)tmpmax;
1609
port = (uint16_t)tmpmax;
2304
1610
*address = '\0';
1611
address = connect_to;
2305
1612
/* Colon in address indicates IPv6 */
2306
1613
int af;
2307
if(strchr(connect_to, ':') != NULL){
1614
if(strchr(address, ':') != NULL){
2308
1615
af = AF_INET6;
2309
/* Accept [] around IPv6 address - see RFC 5952 */
2310
if(connect_to[0] == '[' and address[-1] == ']')
2311
{
2312
connect_to++;
2313
address[-1] = '\0';
2314
}
2315
1616
} else {
2316
1617
af = AF_INET;
2317
1618
}
2318
address = connect_to;
2319
1619
2320
1620
if(quit_now){
2321
1621
goto end;
2322
1622
}
2323
1623
2324
1624
while(not quit_now){
2325
ret = start_mandos_communication(address, port, if_index, af,
2326
&mc);
1625
ret = start_mandos_communication(address, port, if_index, af);
2327
1626
if(quit_now or ret == 0){
2328
1627
break;
2329
1628
}
2330
if(debug){
2331
fprintf_plus(stderr, "Retrying in %d seconds\n",
2332
(int)retry_interval);
2333
}
2334
sleep((unsigned int)retry_interval);
2335
}
2336
1629
sleep(15);
1630
};
1631
2337
1632
if (not quit_now){
2338
1633
exitcode = EXIT_SUCCESS;
2339
1634
}
2340
1635
2341
1636
goto end;
2342
1637
}
2343
1638
2355
1650
config.publish_domain = 0;
2356
1651
2357
1652
/* Allocate a new server */
2358
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2359
&config, NULL, NULL, &ret_errno);
1653
mc.server = avahi_server_new(avahi_simple_poll_get
1654
(mc.simple_poll), &config, NULL,
1655
NULL, &error);
2360
1656
2361
1657
/* Free the Avahi configuration data */
2362
1658
avahi_server_config_free(&config);
2364
1660
2365
1661
/* Check if creating the Avahi server object succeeded */
2366
1662
if(mc.server == NULL){
2367
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2368
avahi_strerror(ret_errno));
1663
fprintf(stderr, "Failed to create Avahi server: %s\n",
1664
avahi_strerror(error));
2369
1665
exitcode = EX_UNAVAILABLE;
2370
1666
goto end;
2371
1667
}
2377
1673
/* Create the Avahi service browser */
2378
1674
sb = avahi_s_service_browser_new(mc.server, if_index,
2379
1675
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2380
NULL, 0, browse_callback,
2381
(void *)&mc);
1676
NULL, 0, browse_callback, NULL);
2382
1677
if(sb == NULL){
2383
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2384
avahi_strerror(avahi_server_errno(mc.server)));
1678
fprintf(stderr, "Failed to create service browser: %s\n",
1679
avahi_strerror(avahi_server_errno(mc.server)));
2385
1680
exitcode = EX_UNAVAILABLE;
2386
1681
goto end;
2387
1682
}
2393
1688
/* Run the main loop */
2394
1689
2395
1690
if(debug){
2396
fprintf_plus(stderr, "Starting Avahi loop search\n");
2397
}
2398
2399
ret = avahi_loop_with_timeout(simple_poll,
2400
(int)(retry_interval * 1000), &mc);
2401
if(debug){
2402
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2403
(ret == 0) ? "successfully" : "with error");
2404
}
1691
fprintf(stderr, "Starting Avahi loop search\n");
1692
}
1693
1694
avahi_simple_poll_loop(mc.simple_poll);
2405
1695
2406
1696
end:
2407
1697
2408
1698
if(debug){
2409
fprintf_plus(stderr, "%s exiting\n", argv[0]);
1699
fprintf(stderr, "%s exiting\n", argv[0]);
2410
1700
}
2411
1701
2412
1702
/* Cleanup things */
2413
free(mc.interfaces);
2414
2415
1703
if(sb != NULL)
2416
1704
avahi_s_service_browser_free(sb);
2417
1705
2418
1706
if(mc.server != NULL)
2419
1707
avahi_server_free(mc.server);
2420
1708
2421
if(simple_poll != NULL)
2422
avahi_simple_poll_free(simple_poll);
1709
if(mc.simple_poll != NULL)
1710
avahi_simple_poll_free(mc.simple_poll);
2423
1711
2424
1712
if(gnutls_initialized){
2425
1713
gnutls_certificate_free_credentials(mc.cred);
2431
1719
gpgme_release(mc.ctx);
2432
1720
}
2433
1721
2434
/* Cleans up the circular linked list of Mandos servers the client
2435
has seen */
2436
if(mc.current_server != NULL){
2437
mc.current_server->prev->next = NULL;
2438
while(mc.current_server != NULL){
2439
server *next = mc.current_server->next;
2440
free(mc.current_server);
2441
mc.current_server = next;
1722
/* Take down the network interface */
1723
if(take_down_interface){
1724
/* Re-raise priviliges */
1725
errno = 0;
1726
ret = seteuid(0);
1727
if(ret == -1){
1728
perror("seteuid");
2442
1729
}
2443
}
2444
2445
/* Re-raise priviliges */
2446
{
2447
raise_privileges();
2448
2449
/* Run network hooks */
2450
run_network_hooks("stop", interfaces_hooks != NULL ?
2451
interfaces_hooks : "", delay);
2452
2453
/* Take down the network interfaces which were brought up */
2454
{
2455
char *interface = NULL;
2456
while((interface=argz_next(interfaces_to_take_down,
2457
interfaces_to_take_down_size,
2458
interface))){
2459
ret_errno = take_down_interface(interface);
2460
if(ret_errno != 0){
2461
errno = ret_errno;
2462
perror_plus("Failed to take down interface");
1730
if(geteuid() == 0){
1731
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1732
if(ret == -1){
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);
1737
if(ret == -1){
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
2463
1739
}
2464
1740
}
2465
if(debug and (interfaces_to_take_down == NULL)){
2466
fprintf_plus(stderr, "No interfaces needed to be taken"
2467
" down\n");
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1742
if(ret == -1){
1743
perror("close");
1744
}
1745
/* Lower privileges permanently */
1746
errno = 0;
1747
ret = setuid(uid);
1748
if(ret == -1){
1749
perror("setuid");
2468
1750
}
2469
1751
}
2470
2471
lower_privileges_permanently();
2472
1752
}
2473
1753
2474
free(interfaces_to_take_down);
2475
free(interfaces_hooks);
2476
2477
/* Removes the GPGME temp directory and all files inside */
1754
/* Removes the temp directory used by GPGME */
2478
1755
if(tempdir_created){
2479
struct dirent **direntries = NULL;
2480
struct dirent *direntry = NULL;
2481
int numentries = scandir(tempdir, &direntries, notdotentries,
2482
alphasort);
2483
if (numentries > 0){
2484
for(int i = 0; i < numentries; i++){
2485
direntry = direntries[i];
1756
DIR *d;
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1759
if(d == NULL){
1760
if(errno != ENOENT){
1761
perror("opendir");
1762
}
1763
} else {
1764
while(true){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1767
break;
1768
}
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'))){
1774
continue;
1775
}
2486
1776
char *fullname = NULL;
2487
1777
ret = asprintf(&fullname, "%s/%s", tempdir,
2488
1778
direntry->d_name);
2489
1779
if(ret < 0){
2490
perror_plus("asprintf");
1780
perror("asprintf");
2491
1781
continue;
2492
1782
}
2493
1783
ret = remove(fullname);
2494
1784
if(ret == -1){
2495
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2496
strerror(errno));
1785
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1786
strerror(errno));
2497
1787
}
2498
1788
free(fullname);
2499
1789
}
2500
}
2501
2502
/* need to clean even if 0 because man page doesn't specify */
2503
free(direntries);
2504
if (numentries == -1){
2505
perror_plus("scandir");
1790
closedir(d);
2506
1791
}
2507
1792
ret = rmdir(tempdir);
2508
1793
if(ret == -1 and errno != ENOENT){
2509
perror_plus("rmdir");
1794
perror("rmdir");
2510
1795
}
2511
1796
}
2512
1797
2517
1802
&old_sigterm_action,
2518
1803
NULL));
2519
1804
if(ret == -1){
2520
perror_plus("sigaction");
1805
perror("sigaction");
2521
1806
}
2522
1807
do {
2523
1808
ret = raise(signal_received);
2524
1809
} while(ret != 0 and errno == EINTR);
2525
1810
if(ret != 0){
2526
perror_plus("raise");
1811
perror("raise");
2527
1812
abort();
2528
1813
}
2529
1814
TEMP_FAILURE_RETRY(pause());
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0