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- Committer: Teddy Hogeborn
- Date: 2008-01-30 17:28:18 UTC
- Revision ID: teddy@fukt.bsnet.se-20080130172818-fnrq2xmtg1wa8wo2
* client.cpp (main): Get t_old early since it is used on error exits.
* server.py (Client.checker): New attribute.
(Client.check_action, Client.start_checker, Client.stop_checker,
Client.fileno, Client.next_stop, Client.still_valid,
Client.it_is_time_to_check): New methods.
(Client.handle_request): Alias to "check_action".
(main): Stop all started checkers on exit. Exit cleanly on keyboard
interrupt.
* server.py (Client.checker): New attribute.
(Client.check_action, Client.start_checker, Client.stop_checker,
Client.fileno, Client.next_stop, Client.still_valid,
Client.it_is_time_to_check): New methods.
(Client.handle_request): Alias to "check_action".
(main): Stop all started checkers on exit. Exit cleanly on keyboard
interrupt.
- files added:
- ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugins.d
- files renamed:
- clients.conf => mandos-clients.conf
- mandos => server.py
- files modified:
- Makefile
added
removed
plugins.d/mandos-client.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos-client - get and decrypt data from a Mandos server
4
*
5
* This program is partly derived from an example program for an Avahi
6
* service browser, downloaded from
7
* <http://avahi.org/browser/examples/core-browse-services.c>. This
8
* includes the following functions: "resolve_callback",
9
* "browse_callback", and parts of "main".
10
*
11
* Everything else is
12
* Copyright © 2008-2013 Teddy Hogeborn
13
* Copyright © 2008-2013 Björn Påhlsson
14
*
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.
19
*
20
* This program is distributed in the hope that it will be useful, but
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
* General Public License for more details.
24
*
25
* 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
*
29
* Contact the authors at <mandos@recompile.se>.
30
*/
31
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
35
#endif
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
38
#endif
39
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
strtof(), abort() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
59
getnameinfo() */
60
#include <fcntl.h> /* open() */
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
*/
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
strtoimax() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
SIOCSIFFLAGS, if_indextoname(),
70
if_nametoindex(), IF_NAMESIZE */
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
*/
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit() */
77
#include <arpa/inet.h> /* inet_pton(), htons() */
78
#include <iso646.h> /* not, or, and */
79
#include <argp.h> /* struct argp_option, error_t, struct
80
argp_state, struct argp,
81
argp_parse(), ARGP_KEY_ARG,
82
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
83
#include <signal.h> /* sigemptyset(), sigaddset(),
84
sigaction(), SIGTERM, sig_atomic_t,
85
raise() */
86
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
87
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
88
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
89
WEXITSTATUS(), WTERMSIG() */
90
#include <grp.h> /* setgroups() */
91
#include <argz.h> /* argz_add_sep(), argz_next(),
92
argz_delete(), argz_append(),
93
argz_stringify(), argz_add(),
94
argz_count() */
95
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
96
EAI_SYSTEM, gai_strerror() */
97
98
#ifdef __linux__
99
#include <sys/klog.h> /* klogctl() */
100
#endif /* __linux__ */
101
102
/* Avahi */
103
/* All Avahi types, constants and functions
104
Avahi*, avahi_*,
105
AVAHI_* */
106
#include <avahi-core/core.h>
107
#include <avahi-core/lookup.h>
108
#include <avahi-core/log.h>
109
#include <avahi-common/simple-watch.h>
110
#include <avahi-common/malloc.h>
111
#include <avahi-common/error.h>
112
113
/* GnuTLS */
114
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
115
functions:
116
gnutls_*
117
init_gnutls_session(),
118
GNUTLS_* */
119
#include <gnutls/openpgp.h>
120
/* gnutls_certificate_set_openpgp_key_file(),
121
GNUTLS_OPENPGP_FMT_BASE64 */
122
123
/* GPGME */
124
#include <gpgme.h> /* All GPGME types, constants and
125
functions:
126
gpgme_*
127
GPGME_PROTOCOL_OpenPGP,
128
GPG_ERR_NO_* */
129
130
#define BUFFER_SIZE 256
131
132
#define PATHDIR "/conf/conf.d/mandos"
133
#define SECKEY "seckey.txt"
134
#define PUBKEY "pubkey.txt"
135
#define HOOKDIR "/lib/mandos/network-hooks.d"
136
137
bool debug = false;
138
static const char mandos_protocol_version[] = "1";
139
const char * argp_program_version = "mandos-client " VERSION;
140
const char * argp_program_bug_address = "<mandos@recompile.se>";
141
static const char sys_class_net[] = "/sys/class/net";
142
char *connect_to = NULL;
143
const char *hookdir = HOOKDIR;
144
uid_t uid = 65534;
145
gid_t gid = 65534;
146
147
/* Doubly linked list that need to be circularly linked when used */
148
typedef struct server{
149
const char *ip;
150
in_port_t port;
151
AvahiIfIndex if_index;
152
int af;
153
struct timespec last_seen;
154
struct server *next;
155
struct server *prev;
156
} server;
157
158
/* Used for passing in values through the Avahi callback functions */
159
typedef struct {
160
AvahiServer *server;
161
gnutls_certificate_credentials_t cred;
162
unsigned int dh_bits;
163
gnutls_dh_params_t dh_params;
164
const char *priority;
165
gpgme_ctx_t ctx;
166
server *current_server;
167
char *interfaces;
168
size_t interfaces_size;
169
} mandos_context;
170
171
/* global so signal handler can reach it*/
172
AvahiSimplePoll *simple_poll;
173
174
sig_atomic_t quit_now = 0;
175
int signal_received = 0;
176
177
/* Function to use when printing errors */
178
void perror_plus(const char *print_text){
179
int e = errno;
180
fprintf(stderr, "Mandos plugin %s: ",
181
program_invocation_short_name);
182
errno = e;
183
perror(print_text);
184
}
185
186
__attribute__((format (gnu_printf, 2, 3), nonnull))
187
int fprintf_plus(FILE *stream, const char *format, ...){
188
va_list ap;
189
va_start (ap, format);
190
191
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
192
program_invocation_short_name));
193
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
194
}
195
196
/*
197
* Make additional room in "buffer" for at least BUFFER_SIZE more
198
* bytes. "buffer_capacity" is how much is currently allocated,
199
* "buffer_length" is how much is already used.
200
*/
201
__attribute__((nonnull, warn_unused_result))
202
size_t incbuffer(char **buffer, size_t buffer_length,
203
size_t buffer_capacity){
204
if(buffer_length + BUFFER_SIZE > buffer_capacity){
205
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
206
if(new_buf == NULL){
207
int old_errno = errno;
208
free(*buffer);
209
errno = old_errno;
210
*buffer = NULL;
211
return 0;
212
}
213
*buffer = new_buf;
214
buffer_capacity += BUFFER_SIZE;
215
}
216
return buffer_capacity;
217
}
218
219
/* Add server to set of servers to retry periodically */
220
__attribute__((nonnull, warn_unused_result))
221
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
222
int af, server **current_server){
223
int ret;
224
server *new_server = malloc(sizeof(server));
225
if(new_server == NULL){
226
perror_plus("malloc");
227
return false;
228
}
229
*new_server = (server){ .ip = strdup(ip),
230
.port = port,
231
.if_index = if_index,
232
.af = af };
233
if(new_server->ip == NULL){
234
perror_plus("strdup");
235
return false;
236
}
237
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
238
if(ret == -1){
239
perror_plus("clock_gettime");
240
return false;
241
}
242
/* Special case of first server */
243
if(*current_server == NULL){
244
new_server->next = new_server;
245
new_server->prev = new_server;
246
*current_server = new_server;
247
} else {
248
/* Place the new server last in the list */
249
new_server->next = *current_server;
250
new_server->prev = (*current_server)->prev;
251
new_server->prev->next = new_server;
252
(*current_server)->prev = new_server;
253
}
254
return true;
255
}
256
257
/*
258
* Initialize GPGME.
259
*/
260
__attribute__((nonnull, warn_unused_result))
261
static bool init_gpgme(const char * const seckey,
262
const char * const pubkey,
263
const char * const tempdir,
264
mandos_context *mc){
265
gpgme_error_t rc;
266
gpgme_engine_info_t engine_info;
267
268
/*
269
* Helper function to insert pub and seckey to the engine keyring.
270
*/
271
bool import_key(const char * const filename){
272
int ret;
273
int fd;
274
gpgme_data_t pgp_data;
275
276
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
277
if(fd == -1){
278
perror_plus("open");
279
return false;
280
}
281
282
rc = gpgme_data_new_from_fd(&pgp_data, fd);
283
if(rc != GPG_ERR_NO_ERROR){
284
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
286
return false;
287
}
288
289
rc = gpgme_op_import(mc->ctx, pgp_data);
290
if(rc != GPG_ERR_NO_ERROR){
291
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
293
return false;
294
}
295
296
ret = (int)TEMP_FAILURE_RETRY(close(fd));
297
if(ret == -1){
298
perror_plus("close");
299
}
300
gpgme_data_release(pgp_data);
301
return true;
302
}
303
304
if(debug){
305
fprintf_plus(stderr, "Initializing GPGME\n");
306
}
307
308
/* Init GPGME */
309
gpgme_check_version(NULL);
310
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
311
if(rc != GPG_ERR_NO_ERROR){
312
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
313
gpgme_strsource(rc), gpgme_strerror(rc));
314
return false;
315
}
316
317
/* Set GPGME home directory for the OpenPGP engine only */
318
rc = gpgme_get_engine_info(&engine_info);
319
if(rc != GPG_ERR_NO_ERROR){
320
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
321
gpgme_strsource(rc), gpgme_strerror(rc));
322
return false;
323
}
324
while(engine_info != NULL){
325
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
326
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
327
engine_info->file_name, tempdir);
328
break;
329
}
330
engine_info = engine_info->next;
331
}
332
if(engine_info == NULL){
333
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
334
tempdir);
335
return false;
336
}
337
338
/* Create new GPGME "context" */
339
rc = gpgme_new(&(mc->ctx));
340
if(rc != GPG_ERR_NO_ERROR){
341
fprintf_plus(stderr, "Mandos plugin mandos-client: "
342
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
343
gpgme_strerror(rc));
344
return false;
345
}
346
347
if(not import_key(pubkey) or not import_key(seckey)){
348
return false;
349
}
350
351
return true;
352
}
353
354
/*
355
* Decrypt OpenPGP data.
356
* Returns -1 on error
357
*/
358
__attribute__((nonnull, warn_unused_result))
359
static ssize_t pgp_packet_decrypt(const char *cryptotext,
360
size_t crypto_size,
361
char **plaintext,
362
mandos_context *mc){
363
gpgme_data_t dh_crypto, dh_plain;
364
gpgme_error_t rc;
365
ssize_t ret;
366
size_t plaintext_capacity = 0;
367
ssize_t plaintext_length = 0;
368
369
if(debug){
370
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
371
}
372
373
/* Create new GPGME data buffer from memory cryptotext */
374
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
375
0);
376
if(rc != GPG_ERR_NO_ERROR){
377
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
378
gpgme_strsource(rc), gpgme_strerror(rc));
379
return -1;
380
}
381
382
/* Create new empty GPGME data buffer for the plaintext */
383
rc = gpgme_data_new(&dh_plain);
384
if(rc != GPG_ERR_NO_ERROR){
385
fprintf_plus(stderr, "Mandos plugin mandos-client: "
386
"bad gpgme_data_new: %s: %s\n",
387
gpgme_strsource(rc), gpgme_strerror(rc));
388
gpgme_data_release(dh_crypto);
389
return -1;
390
}
391
392
/* Decrypt data from the cryptotext data buffer to the plaintext
393
data buffer */
394
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
395
if(rc != GPG_ERR_NO_ERROR){
396
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
397
gpgme_strsource(rc), gpgme_strerror(rc));
398
plaintext_length = -1;
399
if(debug){
400
gpgme_decrypt_result_t result;
401
result = gpgme_op_decrypt_result(mc->ctx);
402
if(result == NULL){
403
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
404
} else {
405
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
406
result->unsupported_algorithm);
407
fprintf_plus(stderr, "Wrong key usage: %u\n",
408
result->wrong_key_usage);
409
if(result->file_name != NULL){
410
fprintf_plus(stderr, "File name: %s\n", result->file_name);
411
}
412
gpgme_recipient_t recipient;
413
recipient = result->recipients;
414
while(recipient != NULL){
415
fprintf_plus(stderr, "Public key algorithm: %s\n",
416
gpgme_pubkey_algo_name
417
(recipient->pubkey_algo));
418
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
419
fprintf_plus(stderr, "Secret key available: %s\n",
420
recipient->status == GPG_ERR_NO_SECKEY
421
? "No" : "Yes");
422
recipient = recipient->next;
423
}
424
}
425
}
426
goto decrypt_end;
427
}
428
429
if(debug){
430
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
431
}
432
433
/* Seek back to the beginning of the GPGME plaintext data buffer */
434
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
435
perror_plus("gpgme_data_seek");
436
plaintext_length = -1;
437
goto decrypt_end;
438
}
439
440
*plaintext = NULL;
441
while(true){
442
plaintext_capacity = incbuffer(plaintext,
443
(size_t)plaintext_length,
444
plaintext_capacity);
445
if(plaintext_capacity == 0){
446
perror_plus("incbuffer");
447
plaintext_length = -1;
448
goto decrypt_end;
449
}
450
451
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
452
BUFFER_SIZE);
453
/* Print the data, if any */
454
if(ret == 0){
455
/* EOF */
456
break;
457
}
458
if(ret < 0){
459
perror_plus("gpgme_data_read");
460
plaintext_length = -1;
461
goto decrypt_end;
462
}
463
plaintext_length += ret;
464
}
465
466
if(debug){
467
fprintf_plus(stderr, "Decrypted password is: ");
468
for(ssize_t i = 0; i < plaintext_length; i++){
469
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
470
}
471
fprintf(stderr, "\n");
472
}
473
474
decrypt_end:
475
476
/* Delete the GPGME cryptotext data buffer */
477
gpgme_data_release(dh_crypto);
478
479
/* Delete the GPGME plaintext data buffer */
480
gpgme_data_release(dh_plain);
481
return plaintext_length;
482
}
483
484
__attribute__((warn_unused_result))
485
static const char *safer_gnutls_strerror(int value){
486
const char *ret = gnutls_strerror(value);
487
if(ret == NULL)
488
ret = "(unknown)";
489
return ret;
490
}
491
492
/* GnuTLS log function callback */
493
__attribute__((nonnull))
494
static void debuggnutls(__attribute__((unused)) int level,
495
const char* string){
496
fprintf_plus(stderr, "GnuTLS: %s", string);
497
}
498
499
__attribute__((nonnull, warn_unused_result))
500
static int init_gnutls_global(const char *pubkeyfilename,
501
const char *seckeyfilename,
502
mandos_context *mc){
503
int ret;
504
505
if(debug){
506
fprintf_plus(stderr, "Initializing GnuTLS\n");
507
}
508
509
ret = gnutls_global_init();
510
if(ret != GNUTLS_E_SUCCESS){
511
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
512
safer_gnutls_strerror(ret));
513
return -1;
514
}
515
516
if(debug){
517
/* "Use a log level over 10 to enable all debugging options."
518
* - GnuTLS manual
519
*/
520
gnutls_global_set_log_level(11);
521
gnutls_global_set_log_function(debuggnutls);
522
}
523
524
/* OpenPGP credentials */
525
ret = gnutls_certificate_allocate_credentials(&mc->cred);
526
if(ret != GNUTLS_E_SUCCESS){
527
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
528
safer_gnutls_strerror(ret));
529
gnutls_global_deinit();
530
return -1;
531
}
532
533
if(debug){
534
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
535
" secret key %s as GnuTLS credentials\n",
536
pubkeyfilename,
537
seckeyfilename);
538
}
539
540
ret = gnutls_certificate_set_openpgp_key_file
541
(mc->cred, pubkeyfilename, seckeyfilename,
542
GNUTLS_OPENPGP_FMT_BASE64);
543
if(ret != GNUTLS_E_SUCCESS){
544
fprintf_plus(stderr,
545
"Error[%d] while reading the OpenPGP key pair ('%s',"
546
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
547
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
548
safer_gnutls_strerror(ret));
549
goto globalfail;
550
}
551
552
/* GnuTLS server initialization */
553
ret = gnutls_dh_params_init(&mc->dh_params);
554
if(ret != GNUTLS_E_SUCCESS){
555
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
556
" initialization: %s\n",
557
safer_gnutls_strerror(ret));
558
goto globalfail;
559
}
560
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
561
if(ret != GNUTLS_E_SUCCESS){
562
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
563
safer_gnutls_strerror(ret));
564
goto globalfail;
565
}
566
567
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
568
569
return 0;
570
571
globalfail:
572
573
gnutls_certificate_free_credentials(mc->cred);
574
gnutls_global_deinit();
575
gnutls_dh_params_deinit(mc->dh_params);
576
return -1;
577
}
578
579
__attribute__((nonnull, warn_unused_result))
580
static int init_gnutls_session(gnutls_session_t *session,
581
mandos_context *mc){
582
int ret;
583
/* GnuTLS session creation */
584
do {
585
ret = gnutls_init(session, GNUTLS_SERVER);
586
if(quit_now){
587
return -1;
588
}
589
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
590
if(ret != GNUTLS_E_SUCCESS){
591
fprintf_plus(stderr,
592
"Error in GnuTLS session initialization: %s\n",
593
safer_gnutls_strerror(ret));
594
}
595
596
{
597
const char *err;
598
do {
599
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
600
if(quit_now){
601
gnutls_deinit(*session);
602
return -1;
603
}
604
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
605
if(ret != GNUTLS_E_SUCCESS){
606
fprintf_plus(stderr, "Syntax error at: %s\n", err);
607
fprintf_plus(stderr, "GnuTLS error: %s\n",
608
safer_gnutls_strerror(ret));
609
gnutls_deinit(*session);
610
return -1;
611
}
612
}
613
614
do {
615
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
616
mc->cred);
617
if(quit_now){
618
gnutls_deinit(*session);
619
return -1;
620
}
621
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
622
if(ret != GNUTLS_E_SUCCESS){
623
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
624
safer_gnutls_strerror(ret));
625
gnutls_deinit(*session);
626
return -1;
627
}
628
629
/* ignore client certificate if any. */
630
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
631
632
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
633
634
return 0;
635
}
636
637
/* Avahi log function callback */
638
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
639
__attribute__((unused)) const char *txt){}
640
641
/* Called when a Mandos server is found */
642
__attribute__((nonnull, warn_unused_result))
643
static int start_mandos_communication(const char *ip, in_port_t port,
644
AvahiIfIndex if_index,
645
int af, mandos_context *mc){
646
int ret, tcp_sd = -1;
647
ssize_t sret;
648
struct sockaddr_storage to;
649
char *buffer = NULL;
650
char *decrypted_buffer = NULL;
651
size_t buffer_length = 0;
652
size_t buffer_capacity = 0;
653
size_t written;
654
int retval = -1;
655
gnutls_session_t session;
656
int pf; /* Protocol family */
657
658
errno = 0;
659
660
if(quit_now){
661
errno = EINTR;
662
return -1;
663
}
664
665
switch(af){
666
case AF_INET6:
667
pf = PF_INET6;
668
break;
669
case AF_INET:
670
pf = PF_INET;
671
break;
672
default:
673
fprintf_plus(stderr, "Bad address family: %d\n", af);
674
errno = EINVAL;
675
return -1;
676
}
677
678
/* If the interface is specified and we have a list of interfaces */
679
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
680
/* Check if the interface is one of the interfaces we are using */
681
bool match = false;
682
{
683
char *interface = NULL;
684
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
685
interface))){
686
if(if_nametoindex(interface) == (unsigned int)if_index){
687
match = true;
688
break;
689
}
690
}
691
}
692
if(not match){
693
/* This interface does not match any in the list, so we don't
694
connect to the server */
695
if(debug){
696
char interface[IF_NAMESIZE];
697
if(if_indextoname((unsigned int)if_index, interface) == NULL){
698
perror_plus("if_indextoname");
699
} else {
700
fprintf_plus(stderr, "Skipping server on non-used interface"
701
" \"%s\"\n",
702
if_indextoname((unsigned int)if_index,
703
interface));
704
}
705
}
706
return -1;
707
}
708
}
709
710
ret = init_gnutls_session(&session, mc);
711
if(ret != 0){
712
return -1;
713
}
714
715
if(debug){
716
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
717
PRIuMAX "\n", ip, (uintmax_t)port);
718
}
719
720
tcp_sd = socket(pf, SOCK_STREAM, 0);
721
if(tcp_sd < 0){
722
int e = errno;
723
perror_plus("socket");
724
errno = e;
725
goto mandos_end;
726
}
727
728
if(quit_now){
729
errno = EINTR;
730
goto mandos_end;
731
}
732
733
memset(&to, 0, sizeof(to));
734
if(af == AF_INET6){
735
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
736
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
737
} else { /* IPv4 */
738
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
739
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
740
}
741
if(ret < 0 ){
742
int e = errno;
743
perror_plus("inet_pton");
744
errno = e;
745
goto mandos_end;
746
}
747
if(ret == 0){
748
int e = errno;
749
fprintf_plus(stderr, "Bad address: %s\n", ip);
750
errno = e;
751
goto mandos_end;
752
}
753
if(af == AF_INET6){
754
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
755
if(IN6_IS_ADDR_LINKLOCAL
756
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
757
if(if_index == AVAHI_IF_UNSPEC){
758
fprintf_plus(stderr, "An IPv6 link-local address is"
759
" incomplete without a network interface\n");
760
errno = EINVAL;
761
goto mandos_end;
762
}
763
/* Set the network interface number as scope */
764
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
765
}
766
} else {
767
((struct sockaddr_in *)&to)->sin_port = htons(port);
768
}
769
770
if(quit_now){
771
errno = EINTR;
772
goto mandos_end;
773
}
774
775
if(debug){
776
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
777
char interface[IF_NAMESIZE];
778
if(if_indextoname((unsigned int)if_index, interface) == NULL){
779
perror_plus("if_indextoname");
780
} else {
781
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
782
"\n", ip, interface, (uintmax_t)port);
783
}
784
} else {
785
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
786
ip, (uintmax_t)port);
787
}
788
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
789
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
790
if(af == AF_INET6){
791
ret = getnameinfo((struct sockaddr *)&to,
792
sizeof(struct sockaddr_in6),
793
addrstr, sizeof(addrstr), NULL, 0,
794
NI_NUMERICHOST);
795
} else {
796
ret = getnameinfo((struct sockaddr *)&to,
797
sizeof(struct sockaddr_in),
798
addrstr, sizeof(addrstr), NULL, 0,
799
NI_NUMERICHOST);
800
}
801
if(ret == EAI_SYSTEM){
802
perror_plus("getnameinfo");
803
} else if(ret != 0) {
804
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
805
} else if(strcmp(addrstr, ip) != 0){
806
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
807
}
808
}
809
810
if(quit_now){
811
errno = EINTR;
812
goto mandos_end;
813
}
814
815
if(af == AF_INET6){
816
ret = connect(tcp_sd, (struct sockaddr *)&to,
817
sizeof(struct sockaddr_in6));
818
} else {
819
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
820
sizeof(struct sockaddr_in));
821
}
822
if(ret < 0){
823
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
824
int e = errno;
825
perror_plus("connect");
826
errno = e;
827
}
828
goto mandos_end;
829
}
830
831
if(quit_now){
832
errno = EINTR;
833
goto mandos_end;
834
}
835
836
const char *out = mandos_protocol_version;
837
written = 0;
838
while(true){
839
size_t out_size = strlen(out);
840
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
841
out_size - written));
842
if(ret == -1){
843
int e = errno;
844
perror_plus("write");
845
errno = e;
846
goto mandos_end;
847
}
848
written += (size_t)ret;
849
if(written < out_size){
850
continue;
851
} else {
852
if(out == mandos_protocol_version){
853
written = 0;
854
out = "\r\n";
855
} else {
856
break;
857
}
858
}
859
860
if(quit_now){
861
errno = EINTR;
862
goto mandos_end;
863
}
864
}
865
866
if(debug){
867
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
868
}
869
870
if(quit_now){
871
errno = EINTR;
872
goto mandos_end;
873
}
874
875
/* This casting via intptr_t is to eliminate warning about casting
876
an int to a pointer type. This is exactly how the GnuTLS Guile
877
function "set-session-transport-fd!" does it. */
878
gnutls_transport_set_ptr(session,
879
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
880
881
if(quit_now){
882
errno = EINTR;
883
goto mandos_end;
884
}
885
886
do {
887
ret = gnutls_handshake(session);
888
if(quit_now){
889
errno = EINTR;
890
goto mandos_end;
891
}
892
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
893
894
if(ret != GNUTLS_E_SUCCESS){
895
if(debug){
896
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
897
gnutls_perror(ret);
898
}
899
errno = EPROTO;
900
goto mandos_end;
901
}
902
903
/* Read OpenPGP packet that contains the wanted password */
904
905
if(debug){
906
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
907
" %s\n", ip);
908
}
909
910
while(true){
911
912
if(quit_now){
913
errno = EINTR;
914
goto mandos_end;
915
}
916
917
buffer_capacity = incbuffer(&buffer, buffer_length,
918
buffer_capacity);
919
if(buffer_capacity == 0){
920
int e = errno;
921
perror_plus("incbuffer");
922
errno = e;
923
goto mandos_end;
924
}
925
926
if(quit_now){
927
errno = EINTR;
928
goto mandos_end;
929
}
930
931
sret = gnutls_record_recv(session, buffer+buffer_length,
932
BUFFER_SIZE);
933
if(sret == 0){
934
break;
935
}
936
if(sret < 0){
937
switch(sret){
938
case GNUTLS_E_INTERRUPTED:
939
case GNUTLS_E_AGAIN:
940
break;
941
case GNUTLS_E_REHANDSHAKE:
942
do {
943
ret = gnutls_handshake(session);
944
945
if(quit_now){
946
errno = EINTR;
947
goto mandos_end;
948
}
949
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
950
if(ret < 0){
951
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
952
"***\n");
953
gnutls_perror(ret);
954
errno = EPROTO;
955
goto mandos_end;
956
}
957
break;
958
default:
959
fprintf_plus(stderr, "Unknown error while reading data from"
960
" encrypted session with Mandos server\n");
961
gnutls_bye(session, GNUTLS_SHUT_RDWR);
962
errno = EIO;
963
goto mandos_end;
964
}
965
} else {
966
buffer_length += (size_t) sret;
967
}
968
}
969
970
if(debug){
971
fprintf_plus(stderr, "Closing TLS session\n");
972
}
973
974
if(quit_now){
975
errno = EINTR;
976
goto mandos_end;
977
}
978
979
do {
980
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
981
if(quit_now){
982
errno = EINTR;
983
goto mandos_end;
984
}
985
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
986
987
if(buffer_length > 0){
988
ssize_t decrypted_buffer_size;
989
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
990
&decrypted_buffer, mc);
991
if(decrypted_buffer_size >= 0){
992
993
written = 0;
994
while(written < (size_t) decrypted_buffer_size){
995
if(quit_now){
996
errno = EINTR;
997
goto mandos_end;
998
}
999
1000
ret = (int)fwrite(decrypted_buffer + written, 1,
1001
(size_t)decrypted_buffer_size - written,
1002
stdout);
1003
if(ret == 0 and ferror(stdout)){
1004
int e = errno;
1005
if(debug){
1006
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1007
strerror(errno));
1008
}
1009
errno = e;
1010
goto mandos_end;
1011
}
1012
written += (size_t)ret;
1013
}
1014
retval = 0;
1015
}
1016
}
1017
1018
/* Shutdown procedure */
1019
1020
mandos_end:
1021
{
1022
int e = errno;
1023
free(decrypted_buffer);
1024
free(buffer);
1025
if(tcp_sd >= 0){
1026
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1027
}
1028
if(ret == -1){
1029
if(e == 0){
1030
e = errno;
1031
}
1032
perror_plus("close");
1033
}
1034
gnutls_deinit(session);
1035
errno = e;
1036
if(quit_now){
1037
errno = EINTR;
1038
retval = -1;
1039
}
1040
}
1041
return retval;
1042
}
1043
1044
__attribute__((nonnull))
1045
static void resolve_callback(AvahiSServiceResolver *r,
1046
AvahiIfIndex interface,
1047
AvahiProtocol proto,
1048
AvahiResolverEvent event,
1049
const char *name,
1050
const char *type,
1051
const char *domain,
1052
const char *host_name,
1053
const AvahiAddress *address,
1054
uint16_t port,
1055
AVAHI_GCC_UNUSED AvahiStringList *txt,
1056
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1057
flags,
1058
void *mc){
1059
if(r == NULL){
1060
return;
1061
}
1062
1063
/* Called whenever a service has been resolved successfully or
1064
timed out */
1065
1066
if(quit_now){
1067
return;
1068
}
1069
1070
switch(event){
1071
default:
1072
case AVAHI_RESOLVER_FAILURE:
1073
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1074
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1075
domain,
1076
avahi_strerror(avahi_server_errno
1077
(((mandos_context*)mc)->server)));
1078
break;
1079
1080
case AVAHI_RESOLVER_FOUND:
1081
{
1082
char ip[AVAHI_ADDRESS_STR_MAX];
1083
avahi_address_snprint(ip, sizeof(ip), address);
1084
if(debug){
1085
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1086
PRIdMAX ") on port %" PRIu16 "\n", name,
1087
host_name, ip, (intmax_t)interface, port);
1088
}
1089
int ret = start_mandos_communication(ip, (in_port_t)port,
1090
interface,
1091
avahi_proto_to_af(proto),
1092
mc);
1093
if(ret == 0){
1094
avahi_simple_poll_quit(simple_poll);
1095
} else {
1096
if(not add_server(ip, (in_port_t)port, interface,
1097
avahi_proto_to_af(proto),
1098
&((mandos_context*)mc)->current_server)){
1099
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1100
" list\n", name);
1101
}
1102
}
1103
}
1104
}
1105
avahi_s_service_resolver_free(r);
1106
}
1107
1108
static void browse_callback(AvahiSServiceBrowser *b,
1109
AvahiIfIndex interface,
1110
AvahiProtocol protocol,
1111
AvahiBrowserEvent event,
1112
const char *name,
1113
const char *type,
1114
const char *domain,
1115
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1116
flags,
1117
void *mc){
1118
if(b == NULL){
1119
return;
1120
}
1121
1122
/* Called whenever a new services becomes available on the LAN or
1123
is removed from the LAN */
1124
1125
if(quit_now){
1126
return;
1127
}
1128
1129
switch(event){
1130
default:
1131
case AVAHI_BROWSER_FAILURE:
1132
1133
fprintf_plus(stderr, "(Avahi browser) %s\n",
1134
avahi_strerror(avahi_server_errno
1135
(((mandos_context*)mc)->server)));
1136
avahi_simple_poll_quit(simple_poll);
1137
return;
1138
1139
case AVAHI_BROWSER_NEW:
1140
/* We ignore the returned Avahi resolver object. In the callback
1141
function we free it. If the Avahi server is terminated before
1142
the callback function is called the Avahi server will free the
1143
resolver for us. */
1144
1145
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1146
interface, protocol, name, type,
1147
domain, protocol, 0,
1148
resolve_callback, mc) == NULL)
1149
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1150
" %s\n", name,
1151
avahi_strerror(avahi_server_errno
1152
(((mandos_context*)mc)->server)));
1153
break;
1154
1155
case AVAHI_BROWSER_REMOVE:
1156
break;
1157
1158
case AVAHI_BROWSER_ALL_FOR_NOW:
1159
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1160
if(debug){
1161
fprintf_plus(stderr, "No Mandos server found, still"
1162
" searching...\n");
1163
}
1164
break;
1165
}
1166
}
1167
1168
/* Signal handler that stops main loop after SIGTERM */
1169
static void handle_sigterm(int sig){
1170
if(quit_now){
1171
return;
1172
}
1173
quit_now = 1;
1174
signal_received = sig;
1175
int old_errno = errno;
1176
/* set main loop to exit */
1177
if(simple_poll != NULL){
1178
avahi_simple_poll_quit(simple_poll);
1179
}
1180
errno = old_errno;
1181
}
1182
1183
__attribute__((nonnull, warn_unused_result))
1184
bool get_flags(const char *ifname, struct ifreq *ifr){
1185
int ret;
1186
error_t ret_errno;
1187
1188
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1189
if(s < 0){
1190
ret_errno = errno;
1191
perror_plus("socket");
1192
errno = ret_errno;
1193
return false;
1194
}
1195
strcpy(ifr->ifr_name, ifname);
1196
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1197
if(ret == -1){
1198
if(debug){
1199
ret_errno = errno;
1200
perror_plus("ioctl SIOCGIFFLAGS");
1201
errno = ret_errno;
1202
}
1203
return false;
1204
}
1205
return true;
1206
}
1207
1208
__attribute__((nonnull, warn_unused_result))
1209
bool good_flags(const char *ifname, const struct ifreq *ifr){
1210
1211
/* Reject the loopback device */
1212
if(ifr->ifr_flags & IFF_LOOPBACK){
1213
if(debug){
1214
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1215
ifname);
1216
}
1217
return false;
1218
}
1219
/* Accept point-to-point devices only if connect_to is specified */
1220
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1221
if(debug){
1222
fprintf_plus(stderr, "Accepting point-to-point interface"
1223
" \"%s\"\n", ifname);
1224
}
1225
return true;
1226
}
1227
/* Otherwise, reject non-broadcast-capable devices */
1228
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1229
if(debug){
1230
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1231
" \"%s\"\n", ifname);
1232
}
1233
return false;
1234
}
1235
/* Reject non-ARP interfaces (including dummy interfaces) */
1236
if(ifr->ifr_flags & IFF_NOARP){
1237
if(debug){
1238
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1239
ifname);
1240
}
1241
return false;
1242
}
1243
1244
/* Accept this device */
1245
if(debug){
1246
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1247
}
1248
return true;
1249
}
1250
1251
/*
1252
* This function determines if a directory entry in /sys/class/net
1253
* corresponds to an acceptable network device.
1254
* (This function is passed to scandir(3) as a filter function.)
1255
*/
1256
__attribute__((nonnull, warn_unused_result))
1257
int good_interface(const struct dirent *if_entry){
1258
if(if_entry->d_name[0] == '.'){
1259
return 0;
1260
}
1261
1262
struct ifreq ifr;
1263
if(not get_flags(if_entry->d_name, &ifr)){
1264
if(debug){
1265
fprintf_plus(stderr, "Failed to get flags for interface "
1266
"\"%s\"\n", if_entry->d_name);
1267
}
1268
return 0;
1269
}
1270
1271
if(not good_flags(if_entry->d_name, &ifr)){
1272
return 0;
1273
}
1274
return 1;
1275
}
1276
1277
/*
1278
* This function determines if a network interface is up.
1279
*/
1280
__attribute__((nonnull, warn_unused_result))
1281
bool interface_is_up(const char *interface){
1282
struct ifreq ifr;
1283
if(not get_flags(interface, &ifr)){
1284
if(debug){
1285
fprintf_plus(stderr, "Failed to get flags for interface "
1286
"\"%s\"\n", interface);
1287
}
1288
return false;
1289
}
1290
1291
return (bool)(ifr.ifr_flags & IFF_UP);
1292
}
1293
1294
/*
1295
* This function determines if a network interface is running
1296
*/
1297
__attribute__((nonnull, warn_unused_result))
1298
bool interface_is_running(const char *interface){
1299
struct ifreq ifr;
1300
if(not get_flags(interface, &ifr)){
1301
if(debug){
1302
fprintf_plus(stderr, "Failed to get flags for interface "
1303
"\"%s\"\n", interface);
1304
}
1305
return false;
1306
}
1307
1308
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1309
}
1310
1311
__attribute__((nonnull, pure, warn_unused_result))
1312
int notdotentries(const struct dirent *direntry){
1313
/* Skip "." and ".." */
1314
if(direntry->d_name[0] == '.'
1315
and (direntry->d_name[1] == '\0'
1316
or (direntry->d_name[1] == '.'
1317
and direntry->d_name[2] == '\0'))){
1318
return 0;
1319
}
1320
return 1;
1321
}
1322
1323
/* Is this directory entry a runnable program? */
1324
__attribute__((nonnull, warn_unused_result))
1325
int runnable_hook(const struct dirent *direntry){
1326
int ret;
1327
size_t sret;
1328
struct stat st;
1329
1330
if((direntry->d_name)[0] == '\0'){
1331
/* Empty name? */
1332
return 0;
1333
}
1334
1335
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1336
"abcdefghijklmnopqrstuvwxyz"
1337
"0123456789"
1338
"_-");
1339
if((direntry->d_name)[sret] != '\0'){
1340
/* Contains non-allowed characters */
1341
if(debug){
1342
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1343
direntry->d_name);
1344
}
1345
return 0;
1346
}
1347
1348
char *fullname = NULL;
1349
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1350
if(ret < 0){
1351
perror_plus("asprintf");
1352
return 0;
1353
}
1354
1355
ret = stat(fullname, &st);
1356
if(ret == -1){
1357
if(debug){
1358
perror_plus("Could not stat hook");
1359
}
1360
return 0;
1361
}
1362
if(not (S_ISREG(st.st_mode))){
1363
/* Not a regular file */
1364
if(debug){
1365
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1366
direntry->d_name);
1367
}
1368
return 0;
1369
}
1370
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1371
/* Not executable */
1372
if(debug){
1373
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1374
direntry->d_name);
1375
}
1376
return 0;
1377
}
1378
if(debug){
1379
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1380
direntry->d_name);
1381
}
1382
return 1;
1383
}
1384
1385
__attribute__((nonnull, warn_unused_result))
1386
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1387
mandos_context *mc){
1388
int ret;
1389
struct timespec now;
1390
struct timespec waited_time;
1391
intmax_t block_time;
1392
1393
while(true){
1394
if(mc->current_server == NULL){
1395
if(debug){
1396
fprintf_plus(stderr, "Wait until first server is found."
1397
" No timeout!\n");
1398
}
1399
ret = avahi_simple_poll_iterate(s, -1);
1400
} else {
1401
if(debug){
1402
fprintf_plus(stderr, "Check current_server if we should run"
1403
" it, or wait\n");
1404
}
1405
/* the current time */
1406
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1407
if(ret == -1){
1408
perror_plus("clock_gettime");
1409
return -1;
1410
}
1411
/* Calculating in ms how long time between now and server
1412
who we visted longest time ago. Now - last seen. */
1413
waited_time.tv_sec = (now.tv_sec
1414
- mc->current_server->last_seen.tv_sec);
1415
waited_time.tv_nsec = (now.tv_nsec
1416
- mc->current_server->last_seen.tv_nsec);
1417
/* total time is 10s/10,000ms.
1418
Converting to s from ms by dividing by 1,000,
1419
and ns to ms by dividing by 1,000,000. */
1420
block_time = ((retry_interval
1421
- ((intmax_t)waited_time.tv_sec * 1000))
1422
- ((intmax_t)waited_time.tv_nsec / 1000000));
1423
1424
if(debug){
1425
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1426
block_time);
1427
}
1428
1429
if(block_time <= 0){
1430
ret = start_mandos_communication(mc->current_server->ip,
1431
mc->current_server->port,
1432
mc->current_server->if_index,
1433
mc->current_server->af, mc);
1434
if(ret == 0){
1435
avahi_simple_poll_quit(s);
1436
return 0;
1437
}
1438
ret = clock_gettime(CLOCK_MONOTONIC,
1439
&mc->current_server->last_seen);
1440
if(ret == -1){
1441
perror_plus("clock_gettime");
1442
return -1;
1443
}
1444
mc->current_server = mc->current_server->next;
1445
block_time = 0; /* Call avahi to find new Mandos
1446
servers, but don't block */
1447
}
1448
1449
ret = avahi_simple_poll_iterate(s, (int)block_time);
1450
}
1451
if(ret != 0){
1452
if(ret > 0 or errno != EINTR){
1453
return (ret != 1) ? ret : 0;
1454
}
1455
}
1456
}
1457
}
1458
1459
/* Set effective uid to 0, return errno */
1460
__attribute__((warn_unused_result))
1461
error_t raise_privileges(void){
1462
error_t old_errno = errno;
1463
error_t ret_errno = 0;
1464
if(seteuid(0) == -1){
1465
ret_errno = errno;
1466
perror_plus("seteuid");
1467
}
1468
errno = old_errno;
1469
return ret_errno;
1470
}
1471
1472
/* Set effective and real user ID to 0. Return errno. */
1473
__attribute__((warn_unused_result))
1474
error_t raise_privileges_permanently(void){
1475
error_t old_errno = errno;
1476
error_t ret_errno = raise_privileges();
1477
if(ret_errno != 0){
1478
errno = old_errno;
1479
return ret_errno;
1480
}
1481
if(setuid(0) == -1){
1482
ret_errno = errno;
1483
perror_plus("seteuid");
1484
}
1485
errno = old_errno;
1486
return ret_errno;
1487
}
1488
1489
/* Set effective user ID to unprivileged saved user ID */
1490
__attribute__((warn_unused_result))
1491
error_t lower_privileges(void){
1492
error_t old_errno = errno;
1493
error_t ret_errno = 0;
1494
if(seteuid(uid) == -1){
1495
ret_errno = errno;
1496
perror_plus("seteuid");
1497
}
1498
errno = old_errno;
1499
return ret_errno;
1500
}
1501
1502
/* Lower privileges permanently */
1503
__attribute__((warn_unused_result))
1504
error_t lower_privileges_permanently(void){
1505
error_t old_errno = errno;
1506
error_t ret_errno = 0;
1507
if(setuid(uid) == -1){
1508
ret_errno = errno;
1509
perror_plus("setuid");
1510
}
1511
errno = old_errno;
1512
return ret_errno;
1513
}
1514
1515
__attribute__((nonnull))
1516
void run_network_hooks(const char *mode, const char *interface,
1517
const float delay){
1518
struct dirent **direntries;
1519
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1520
alphasort);
1521
if(numhooks == -1){
1522
if(errno == ENOENT){
1523
if(debug){
1524
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1525
" found\n", hookdir);
1526
}
1527
} else {
1528
perror_plus("scandir");
1529
}
1530
} else {
1531
struct dirent *direntry;
1532
int ret;
1533
int devnull = open("/dev/null", O_RDONLY);
1534
for(int i = 0; i < numhooks; i++){
1535
direntry = direntries[i];
1536
char *fullname = NULL;
1537
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1538
if(ret < 0){
1539
perror_plus("asprintf");
1540
continue;
1541
}
1542
if(debug){
1543
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1544
direntry->d_name);
1545
}
1546
pid_t hook_pid = fork();
1547
if(hook_pid == 0){
1548
/* Child */
1549
/* Raise privileges */
1550
if(raise_privileges_permanently() != 0){
1551
perror_plus("Failed to raise privileges");
1552
_exit(EX_NOPERM);
1553
}
1554
/* Set group */
1555
errno = 0;
1556
ret = setgid(0);
1557
if(ret == -1){
1558
perror_plus("setgid");
1559
_exit(EX_NOPERM);
1560
}
1561
/* Reset supplementary groups */
1562
errno = 0;
1563
ret = setgroups(0, NULL);
1564
if(ret == -1){
1565
perror_plus("setgroups");
1566
_exit(EX_NOPERM);
1567
}
1568
ret = dup2(devnull, STDIN_FILENO);
1569
if(ret == -1){
1570
perror_plus("dup2(devnull, STDIN_FILENO)");
1571
_exit(EX_OSERR);
1572
}
1573
ret = close(devnull);
1574
if(ret == -1){
1575
perror_plus("close");
1576
_exit(EX_OSERR);
1577
}
1578
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1579
if(ret == -1){
1580
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1581
_exit(EX_OSERR);
1582
}
1583
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1584
if(ret == -1){
1585
perror_plus("setenv");
1586
_exit(EX_OSERR);
1587
}
1588
ret = setenv("DEVICE", interface, 1);
1589
if(ret == -1){
1590
perror_plus("setenv");
1591
_exit(EX_OSERR);
1592
}
1593
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1594
if(ret == -1){
1595
perror_plus("setenv");
1596
_exit(EX_OSERR);
1597
}
1598
ret = setenv("MODE", mode, 1);
1599
if(ret == -1){
1600
perror_plus("setenv");
1601
_exit(EX_OSERR);
1602
}
1603
char *delaystring;
1604
ret = asprintf(&delaystring, "%f", (double)delay);
1605
if(ret == -1){
1606
perror_plus("asprintf");
1607
_exit(EX_OSERR);
1608
}
1609
ret = setenv("DELAY", delaystring, 1);
1610
if(ret == -1){
1611
free(delaystring);
1612
perror_plus("setenv");
1613
_exit(EX_OSERR);
1614
}
1615
free(delaystring);
1616
if(connect_to != NULL){
1617
ret = setenv("CONNECT", connect_to, 1);
1618
if(ret == -1){
1619
perror_plus("setenv");
1620
_exit(EX_OSERR);
1621
}
1622
}
1623
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1624
perror_plus("execl");
1625
_exit(EXIT_FAILURE);
1626
}
1627
} else {
1628
int status;
1629
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1630
perror_plus("waitpid");
1631
free(fullname);
1632
continue;
1633
}
1634
if(WIFEXITED(status)){
1635
if(WEXITSTATUS(status) != 0){
1636
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1637
" with status %d\n", direntry->d_name,
1638
WEXITSTATUS(status));
1639
free(fullname);
1640
continue;
1641
}
1642
} else if(WIFSIGNALED(status)){
1643
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1644
" signal %d\n", direntry->d_name,
1645
WTERMSIG(status));
1646
free(fullname);
1647
continue;
1648
} else {
1649
fprintf_plus(stderr, "Warning: network hook \"%s\""
1650
" crashed\n", direntry->d_name);
1651
free(fullname);
1652
continue;
1653
}
1654
}
1655
free(fullname);
1656
if(debug){
1657
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1658
direntry->d_name);
1659
}
1660
}
1661
close(devnull);
1662
}
1663
}
1664
1665
__attribute__((nonnull, warn_unused_result))
1666
error_t bring_up_interface(const char *const interface,
1667
const float delay){
1668
error_t old_errno = errno;
1669
int ret;
1670
struct ifreq network;
1671
unsigned int if_index = if_nametoindex(interface);
1672
if(if_index == 0){
1673
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1674
errno = old_errno;
1675
return ENXIO;
1676
}
1677
1678
if(quit_now){
1679
errno = old_errno;
1680
return EINTR;
1681
}
1682
1683
if(not interface_is_up(interface)){
1684
error_t ret_errno = 0, ioctl_errno = 0;
1685
if(not get_flags(interface, &network)){
1686
ret_errno = errno;
1687
fprintf_plus(stderr, "Failed to get flags for interface "
1688
"\"%s\"\n", interface);
1689
errno = old_errno;
1690
return ret_errno;
1691
}
1692
network.ifr_flags |= IFF_UP; /* set flag */
1693
1694
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1695
if(sd == -1){
1696
ret_errno = errno;
1697
perror_plus("socket");
1698
errno = old_errno;
1699
return ret_errno;
1700
}
1701
1702
if(quit_now){
1703
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1704
if(ret == -1){
1705
perror_plus("close");
1706
}
1707
errno = old_errno;
1708
return EINTR;
1709
}
1710
1711
if(debug){
1712
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1713
interface);
1714
}
1715
1716
/* Raise privileges */
1717
ret_errno = raise_privileges();
1718
bool restore_loglevel = false;
1719
if(ret_errno != 0){
1720
perror_plus("Failed to raise privileges");
1721
}
1722
#ifdef __linux__
1723
int ret_linux;
1724
if(ret_errno == 0){
1725
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1726
messages about the network interface to mess up the prompt */
1727
ret_linux = klogctl(8, NULL, 5);
1728
if(ret_linux == -1){
1729
perror_plus("klogctl");
1730
} else {
1731
restore_loglevel = true;
1732
}
1733
}
1734
#endif /* __linux__ */
1735
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1736
ioctl_errno = errno;
1737
#ifdef __linux__
1738
if(restore_loglevel){
1739
ret_linux = klogctl(7, NULL, 0);
1740
if(ret_linux == -1){
1741
perror_plus("klogctl");
1742
}
1743
}
1744
#endif /* __linux__ */
1745
1746
/* If raise_privileges() succeeded above */
1747
if(ret_errno == 0){
1748
/* Lower privileges */
1749
ret_errno = lower_privileges();
1750
if(ret_errno != 0){
1751
errno = ret_errno;
1752
perror_plus("Failed to lower privileges");
1753
}
1754
}
1755
1756
/* Close the socket */
1757
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1758
if(ret == -1){
1759
perror_plus("close");
1760
}
1761
1762
if(ret_setflags == -1){
1763
errno = ioctl_errno;
1764
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1765
errno = old_errno;
1766
return ioctl_errno;
1767
}
1768
} else if(debug){
1769
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1770
interface);
1771
}
1772
1773
/* Sleep checking until interface is running.
1774
Check every 0.25s, up to total time of delay */
1775
for(int i=0; i < delay * 4; i++){
1776
if(interface_is_running(interface)){
1777
break;
1778
}
1779
struct timespec sleeptime = { .tv_nsec = 250000000 };
1780
ret = nanosleep(&sleeptime, NULL);
1781
if(ret == -1 and errno != EINTR){
1782
perror_plus("nanosleep");
1783
}
1784
}
1785
1786
errno = old_errno;
1787
return 0;
1788
}
1789
1790
__attribute__((nonnull, warn_unused_result))
1791
error_t take_down_interface(const char *const interface){
1792
error_t old_errno = errno;
1793
struct ifreq network;
1794
unsigned int if_index = if_nametoindex(interface);
1795
if(if_index == 0){
1796
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1797
errno = old_errno;
1798
return ENXIO;
1799
}
1800
if(interface_is_up(interface)){
1801
error_t ret_errno = 0, ioctl_errno = 0;
1802
if(not get_flags(interface, &network) and debug){
1803
ret_errno = errno;
1804
fprintf_plus(stderr, "Failed to get flags for interface "
1805
"\"%s\"\n", interface);
1806
errno = old_errno;
1807
return ret_errno;
1808
}
1809
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1810
1811
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1812
if(sd == -1){
1813
ret_errno = errno;
1814
perror_plus("socket");
1815
errno = old_errno;
1816
return ret_errno;
1817
}
1818
1819
if(debug){
1820
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1821
interface);
1822
}
1823
1824
/* Raise privileges */
1825
ret_errno = raise_privileges();
1826
if(ret_errno != 0){
1827
perror_plus("Failed to raise privileges");
1828
}
1829
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1830
ioctl_errno = errno;
1831
1832
/* If raise_privileges() succeeded above */
1833
if(ret_errno == 0){
1834
/* Lower privileges */
1835
ret_errno = lower_privileges();
1836
if(ret_errno != 0){
1837
errno = ret_errno;
1838
perror_plus("Failed to lower privileges");
1839
}
1840
}
1841
1842
/* Close the socket */
1843
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1844
if(ret == -1){
1845
perror_plus("close");
1846
}
1847
1848
if(ret_setflags == -1){
1849
errno = ioctl_errno;
1850
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1851
errno = old_errno;
1852
return ioctl_errno;
1853
}
1854
} else if(debug){
1855
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1856
interface);
1857
}
1858
1859
errno = old_errno;
1860
return 0;
1861
}
1862
1863
int main(int argc, char *argv[]){
1864
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1865
.priority = "SECURE256:!CTYPE-X.509:"
1866
"+CTYPE-OPENPGP", .current_server = NULL,
1867
.interfaces = NULL, .interfaces_size = 0 };
1868
AvahiSServiceBrowser *sb = NULL;
1869
error_t ret_errno;
1870
int ret;
1871
intmax_t tmpmax;
1872
char *tmp;
1873
int exitcode = EXIT_SUCCESS;
1874
char *interfaces_to_take_down = NULL;
1875
size_t interfaces_to_take_down_size = 0;
1876
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1877
char old_tempdir[] = "/tmp/mandosXXXXXX";
1878
char *tempdir = NULL;
1879
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1880
const char *seckey = PATHDIR "/" SECKEY;
1881
const char *pubkey = PATHDIR "/" PUBKEY;
1882
char *interfaces_hooks = NULL;
1883
1884
bool gnutls_initialized = false;
1885
bool gpgme_initialized = false;
1886
float delay = 2.5f;
1887
double retry_interval = 10; /* 10s between trying a server and
1888
retrying the same server again */
1889
1890
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1891
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1892
1893
uid = getuid();
1894
gid = getgid();
1895
1896
/* Lower any group privileges we might have, just to be safe */
1897
errno = 0;
1898
ret = setgid(gid);
1899
if(ret == -1){
1900
perror_plus("setgid");
1901
}
1902
1903
/* Lower user privileges (temporarily) */
1904
errno = 0;
1905
ret = seteuid(uid);
1906
if(ret == -1){
1907
perror_plus("seteuid");
1908
}
1909
1910
if(quit_now){
1911
goto end;
1912
}
1913
1914
{
1915
struct argp_option options[] = {
1916
{ .name = "debug", .key = 128,
1917
.doc = "Debug mode", .group = 3 },
1918
{ .name = "connect", .key = 'c',
1919
.arg = "ADDRESS:PORT",
1920
.doc = "Connect directly to a specific Mandos server",
1921
.group = 1 },
1922
{ .name = "interface", .key = 'i',
1923
.arg = "NAME",
1924
.doc = "Network interface that will be used to search for"
1925
" Mandos servers",
1926
.group = 1 },
1927
{ .name = "seckey", .key = 's',
1928
.arg = "FILE",
1929
.doc = "OpenPGP secret key file base name",
1930
.group = 1 },
1931
{ .name = "pubkey", .key = 'p',
1932
.arg = "FILE",
1933
.doc = "OpenPGP public key file base name",
1934
.group = 2 },
1935
{ .name = "dh-bits", .key = 129,
1936
.arg = "BITS",
1937
.doc = "Bit length of the prime number used in the"
1938
" Diffie-Hellman key exchange",
1939
.group = 2 },
1940
{ .name = "priority", .key = 130,
1941
.arg = "STRING",
1942
.doc = "GnuTLS priority string for the TLS handshake",
1943
.group = 1 },
1944
{ .name = "delay", .key = 131,
1945
.arg = "SECONDS",
1946
.doc = "Maximum delay to wait for interface startup",
1947
.group = 2 },
1948
{ .name = "retry", .key = 132,
1949
.arg = "SECONDS",
1950
.doc = "Retry interval used when denied by the Mandos server",
1951
.group = 2 },
1952
{ .name = "network-hook-dir", .key = 133,
1953
.arg = "DIR",
1954
.doc = "Directory where network hooks are located",
1955
.group = 2 },
1956
/*
1957
* These reproduce what we would get without ARGP_NO_HELP
1958
*/
1959
{ .name = "help", .key = '?',
1960
.doc = "Give this help list", .group = -1 },
1961
{ .name = "usage", .key = -3,
1962
.doc = "Give a short usage message", .group = -1 },
1963
{ .name = "version", .key = 'V',
1964
.doc = "Print program version", .group = -1 },
1965
{ .name = NULL }
1966
};
1967
1968
error_t parse_opt(int key, char *arg,
1969
struct argp_state *state){
1970
errno = 0;
1971
switch(key){
1972
case 128: /* --debug */
1973
debug = true;
1974
break;
1975
case 'c': /* --connect */
1976
connect_to = arg;
1977
break;
1978
case 'i': /* --interface */
1979
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1980
arg, (int)',');
1981
if(ret_errno != 0){
1982
argp_error(state, "%s", strerror(ret_errno));
1983
}
1984
break;
1985
case 's': /* --seckey */
1986
seckey = arg;
1987
break;
1988
case 'p': /* --pubkey */
1989
pubkey = arg;
1990
break;
1991
case 129: /* --dh-bits */
1992
errno = 0;
1993
tmpmax = strtoimax(arg, &tmp, 10);
1994
if(errno != 0 or tmp == arg or *tmp != '\0'
1995
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1996
argp_error(state, "Bad number of DH bits");
1997
}
1998
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1999
break;
2000
case 130: /* --priority */
2001
mc.priority = arg;
2002
break;
2003
case 131: /* --delay */
2004
errno = 0;
2005
delay = strtof(arg, &tmp);
2006
if(errno != 0 or tmp == arg or *tmp != '\0'){
2007
argp_error(state, "Bad delay");
2008
}
2009
case 132: /* --retry */
2010
errno = 0;
2011
retry_interval = strtod(arg, &tmp);
2012
if(errno != 0 or tmp == arg or *tmp != '\0'
2013
or (retry_interval * 1000) > INT_MAX
2014
or retry_interval < 0){
2015
argp_error(state, "Bad retry interval");
2016
}
2017
break;
2018
case 133: /* --network-hook-dir */
2019
hookdir = arg;
2020
break;
2021
/*
2022
* These reproduce what we would get without ARGP_NO_HELP
2023
*/
2024
case '?': /* --help */
2025
argp_state_help(state, state->out_stream,
2026
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2027
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2028
case -3: /* --usage */
2029
argp_state_help(state, state->out_stream,
2030
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2031
case 'V': /* --version */
2032
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2033
exit(argp_err_exit_status);
2034
break;
2035
default:
2036
return ARGP_ERR_UNKNOWN;
2037
}
2038
return errno;
2039
}
2040
2041
struct argp argp = { .options = options, .parser = parse_opt,
2042
.args_doc = "",
2043
.doc = "Mandos client -- Get and decrypt"
2044
" passwords from a Mandos server" };
2045
ret = argp_parse(&argp, argc, argv,
2046
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2047
switch(ret){
2048
case 0:
2049
break;
2050
case ENOMEM:
2051
default:
2052
errno = ret;
2053
perror_plus("argp_parse");
2054
exitcode = EX_OSERR;
2055
goto end;
2056
case EINVAL:
2057
exitcode = EX_USAGE;
2058
goto end;
2059
}
2060
}
2061
2062
{
2063
/* Work around Debian bug #633582:
2064
<http://bugs.debian.org/633582> */
2065
2066
/* Re-raise privileges */
2067
ret_errno = raise_privileges();
2068
if(ret_errno != 0){
2069
errno = ret_errno;
2070
perror_plus("Failed to raise privileges");
2071
} else {
2072
struct stat st;
2073
2074
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2075
int seckey_fd = open(seckey, O_RDONLY);
2076
if(seckey_fd == -1){
2077
perror_plus("open");
2078
} else {
2079
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2080
if(ret == -1){
2081
perror_plus("fstat");
2082
} else {
2083
if(S_ISREG(st.st_mode)
2084
and st.st_uid == 0 and st.st_gid == 0){
2085
ret = fchown(seckey_fd, uid, gid);
2086
if(ret == -1){
2087
perror_plus("fchown");
2088
}
2089
}
2090
}
2091
TEMP_FAILURE_RETRY(close(seckey_fd));
2092
}
2093
}
2094
2095
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2096
int pubkey_fd = open(pubkey, O_RDONLY);
2097
if(pubkey_fd == -1){
2098
perror_plus("open");
2099
} else {
2100
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2101
if(ret == -1){
2102
perror_plus("fstat");
2103
} else {
2104
if(S_ISREG(st.st_mode)
2105
and st.st_uid == 0 and st.st_gid == 0){
2106
ret = fchown(pubkey_fd, uid, gid);
2107
if(ret == -1){
2108
perror_plus("fchown");
2109
}
2110
}
2111
}
2112
TEMP_FAILURE_RETRY(close(pubkey_fd));
2113
}
2114
}
2115
2116
/* Lower privileges */
2117
ret_errno = lower_privileges();
2118
if(ret_errno != 0){
2119
errno = ret_errno;
2120
perror_plus("Failed to lower privileges");
2121
}
2122
}
2123
}
2124
2125
/* Remove invalid interface names (except "none") */
2126
{
2127
char *interface = NULL;
2128
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2129
interface))){
2130
if(strcmp(interface, "none") != 0
2131
and if_nametoindex(interface) == 0){
2132
if(interface[0] != '\0'){
2133
fprintf_plus(stderr, "Not using nonexisting interface"
2134
" \"%s\"\n", interface);
2135
}
2136
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2137
interface = NULL;
2138
}
2139
}
2140
}
2141
2142
/* Run network hooks */
2143
{
2144
if(mc.interfaces != NULL){
2145
interfaces_hooks = malloc(mc.interfaces_size);
2146
if(interfaces_hooks == NULL){
2147
perror_plus("malloc");
2148
goto end;
2149
}
2150
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2151
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2152
}
2153
run_network_hooks("start", interfaces_hooks != NULL ?
2154
interfaces_hooks : "", delay);
2155
}
2156
2157
if(not debug){
2158
avahi_set_log_function(empty_log);
2159
}
2160
2161
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2162
from the signal handler */
2163
/* Initialize the pseudo-RNG for Avahi */
2164
srand((unsigned int) time(NULL));
2165
simple_poll = avahi_simple_poll_new();
2166
if(simple_poll == NULL){
2167
fprintf_plus(stderr,
2168
"Avahi: Failed to create simple poll object.\n");
2169
exitcode = EX_UNAVAILABLE;
2170
goto end;
2171
}
2172
2173
sigemptyset(&sigterm_action.sa_mask);
2174
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2175
if(ret == -1){
2176
perror_plus("sigaddset");
2177
exitcode = EX_OSERR;
2178
goto end;
2179
}
2180
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2181
if(ret == -1){
2182
perror_plus("sigaddset");
2183
exitcode = EX_OSERR;
2184
goto end;
2185
}
2186
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2187
if(ret == -1){
2188
perror_plus("sigaddset");
2189
exitcode = EX_OSERR;
2190
goto end;
2191
}
2192
/* Need to check if the handler is SIG_IGN before handling:
2193
| [[info:libc:Initial Signal Actions]] |
2194
| [[info:libc:Basic Signal Handling]] |
2195
*/
2196
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2197
if(ret == -1){
2198
perror_plus("sigaction");
2199
return EX_OSERR;
2200
}
2201
if(old_sigterm_action.sa_handler != SIG_IGN){
2202
ret = sigaction(SIGINT, &sigterm_action, NULL);
2203
if(ret == -1){
2204
perror_plus("sigaction");
2205
exitcode = EX_OSERR;
2206
goto end;
2207
}
2208
}
2209
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2210
if(ret == -1){
2211
perror_plus("sigaction");
2212
return EX_OSERR;
2213
}
2214
if(old_sigterm_action.sa_handler != SIG_IGN){
2215
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2216
if(ret == -1){
2217
perror_plus("sigaction");
2218
exitcode = EX_OSERR;
2219
goto end;
2220
}
2221
}
2222
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2223
if(ret == -1){
2224
perror_plus("sigaction");
2225
return EX_OSERR;
2226
}
2227
if(old_sigterm_action.sa_handler != SIG_IGN){
2228
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2229
if(ret == -1){
2230
perror_plus("sigaction");
2231
exitcode = EX_OSERR;
2232
goto end;
2233
}
2234
}
2235
2236
/* If no interfaces were specified, make a list */
2237
if(mc.interfaces == NULL){
2238
struct dirent **direntries;
2239
/* Look for any good interfaces */
2240
ret = scandir(sys_class_net, &direntries, good_interface,
2241
alphasort);
2242
if(ret >= 1){
2243
/* Add all found interfaces to interfaces list */
2244
for(int i = 0; i < ret; ++i){
2245
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2246
direntries[i]->d_name);
2247
if(ret_errno != 0){
2248
errno = ret_errno;
2249
perror_plus("argz_add");
2250
continue;
2251
}
2252
if(debug){
2253
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2254
direntries[i]->d_name);
2255
}
2256
}
2257
free(direntries);
2258
} else {
2259
free(direntries);
2260
fprintf_plus(stderr, "Could not find a network interface\n");
2261
exitcode = EXIT_FAILURE;
2262
goto end;
2263
}
2264
}
2265
2266
/* Bring up interfaces which are down, and remove any "none"s */
2267
{
2268
char *interface = NULL;
2269
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2270
interface))){
2271
/* If interface name is "none", stop bringing up interfaces.
2272
Also remove all instances of "none" from the list */
2273
if(strcmp(interface, "none") == 0){
2274
argz_delete(&mc.interfaces, &mc.interfaces_size,
2275
interface);
2276
interface = NULL;
2277
while((interface = argz_next(mc.interfaces,
2278
mc.interfaces_size, interface))){
2279
if(strcmp(interface, "none") == 0){
2280
argz_delete(&mc.interfaces, &mc.interfaces_size,
2281
interface);
2282
interface = NULL;
2283
}
2284
}
2285
break;
2286
}
2287
bool interface_was_up = interface_is_up(interface);
2288
errno = bring_up_interface(interface, delay);
2289
if(not interface_was_up){
2290
if(errno != 0){
2291
perror_plus("Failed to bring up interface");
2292
} else {
2293
errno = argz_add(&interfaces_to_take_down,
2294
&interfaces_to_take_down_size,
2295
interface);
2296
if(errno != 0){
2297
perror_plus("argz_add");
2298
}
2299
}
2300
}
2301
}
2302
if(debug and (interfaces_to_take_down == NULL)){
2303
fprintf_plus(stderr, "No interfaces were brought up\n");
2304
}
2305
}
2306
2307
/* If we only got one interface, explicitly use only that one */
2308
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2309
if(debug){
2310
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2311
mc.interfaces);
2312
}
2313
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2314
}
2315
2316
if(quit_now){
2317
goto end;
2318
}
2319
2320
ret = init_gnutls_global(pubkey, seckey, &mc);
2321
if(ret == -1){
2322
fprintf_plus(stderr, "init_gnutls_global failed\n");
2323
exitcode = EX_UNAVAILABLE;
2324
goto end;
2325
} else {
2326
gnutls_initialized = true;
2327
}
2328
2329
if(quit_now){
2330
goto end;
2331
}
2332
2333
/* Try /run/tmp before /tmp */
2334
tempdir = mkdtemp(run_tempdir);
2335
if(tempdir == NULL and errno == ENOENT){
2336
if(debug){
2337
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2338
run_tempdir, old_tempdir);
2339
}
2340
tempdir = mkdtemp(old_tempdir);
2341
}
2342
if(tempdir == NULL){
2343
perror_plus("mkdtemp");
2344
goto end;
2345
}
2346
2347
if(quit_now){
2348
goto end;
2349
}
2350
2351
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2352
fprintf_plus(stderr, "init_gpgme failed\n");
2353
exitcode = EX_UNAVAILABLE;
2354
goto end;
2355
} else {
2356
gpgme_initialized = true;
2357
}
2358
2359
if(quit_now){
2360
goto end;
2361
}
2362
2363
if(connect_to != NULL){
2364
/* Connect directly, do not use Zeroconf */
2365
/* (Mainly meant for debugging) */
2366
char *address = strrchr(connect_to, ':');
2367
2368
if(address == NULL){
2369
fprintf_plus(stderr, "No colon in address\n");
2370
exitcode = EX_USAGE;
2371
goto end;
2372
}
2373
2374
if(quit_now){
2375
goto end;
2376
}
2377
2378
in_port_t port;
2379
errno = 0;
2380
tmpmax = strtoimax(address+1, &tmp, 10);
2381
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2382
or tmpmax != (in_port_t)tmpmax){
2383
fprintf_plus(stderr, "Bad port number\n");
2384
exitcode = EX_USAGE;
2385
goto end;
2386
}
2387
2388
if(quit_now){
2389
goto end;
2390
}
2391
2392
port = (in_port_t)tmpmax;
2393
*address = '\0';
2394
/* Colon in address indicates IPv6 */
2395
int af;
2396
if(strchr(connect_to, ':') != NULL){
2397
af = AF_INET6;
2398
/* Accept [] around IPv6 address - see RFC 5952 */
2399
if(connect_to[0] == '[' and address[-1] == ']')
2400
{
2401
connect_to++;
2402
address[-1] = '\0';
2403
}
2404
} else {
2405
af = AF_INET;
2406
}
2407
address = connect_to;
2408
2409
if(quit_now){
2410
goto end;
2411
}
2412
2413
while(not quit_now){
2414
ret = start_mandos_communication(address, port, if_index, af,
2415
&mc);
2416
if(quit_now or ret == 0){
2417
break;
2418
}
2419
if(debug){
2420
fprintf_plus(stderr, "Retrying in %d seconds\n",
2421
(int)retry_interval);
2422
}
2423
sleep((unsigned int)retry_interval);
2424
}
2425
2426
if(not quit_now){
2427
exitcode = EXIT_SUCCESS;
2428
}
2429
2430
goto end;
2431
}
2432
2433
if(quit_now){
2434
goto end;
2435
}
2436
2437
{
2438
AvahiServerConfig config;
2439
/* Do not publish any local Zeroconf records */
2440
avahi_server_config_init(&config);
2441
config.publish_hinfo = 0;
2442
config.publish_addresses = 0;
2443
config.publish_workstation = 0;
2444
config.publish_domain = 0;
2445
2446
/* Allocate a new server */
2447
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2448
&config, NULL, NULL, &ret_errno);
2449
2450
/* Free the Avahi configuration data */
2451
avahi_server_config_free(&config);
2452
}
2453
2454
/* Check if creating the Avahi server object succeeded */
2455
if(mc.server == NULL){
2456
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2457
avahi_strerror(ret_errno));
2458
exitcode = EX_UNAVAILABLE;
2459
goto end;
2460
}
2461
2462
if(quit_now){
2463
goto end;
2464
}
2465
2466
/* Create the Avahi service browser */
2467
sb = avahi_s_service_browser_new(mc.server, if_index,
2468
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2469
NULL, 0, browse_callback,
2470
(void *)&mc);
2471
if(sb == NULL){
2472
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2473
avahi_strerror(avahi_server_errno(mc.server)));
2474
exitcode = EX_UNAVAILABLE;
2475
goto end;
2476
}
2477
2478
if(quit_now){
2479
goto end;
2480
}
2481
2482
/* Run the main loop */
2483
2484
if(debug){
2485
fprintf_plus(stderr, "Starting Avahi loop search\n");
2486
}
2487
2488
ret = avahi_loop_with_timeout(simple_poll,
2489
(int)(retry_interval * 1000), &mc);
2490
if(debug){
2491
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2492
(ret == 0) ? "successfully" : "with error");
2493
}
2494
2495
end:
2496
2497
if(debug){
2498
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2499
}
2500
2501
/* Cleanup things */
2502
free(mc.interfaces);
2503
2504
if(sb != NULL)
2505
avahi_s_service_browser_free(sb);
2506
2507
if(mc.server != NULL)
2508
avahi_server_free(mc.server);
2509
2510
if(simple_poll != NULL)
2511
avahi_simple_poll_free(simple_poll);
2512
2513
if(gnutls_initialized){
2514
gnutls_certificate_free_credentials(mc.cred);
2515
gnutls_global_deinit();
2516
gnutls_dh_params_deinit(mc.dh_params);
2517
}
2518
2519
if(gpgme_initialized){
2520
gpgme_release(mc.ctx);
2521
}
2522
2523
/* Cleans up the circular linked list of Mandos servers the client
2524
has seen */
2525
if(mc.current_server != NULL){
2526
mc.current_server->prev->next = NULL;
2527
while(mc.current_server != NULL){
2528
server *next = mc.current_server->next;
2529
free(mc.current_server);
2530
mc.current_server = next;
2531
}
2532
}
2533
2534
/* Re-raise privileges */
2535
{
2536
ret_errno = raise_privileges();
2537
if(ret_errno != 0){
2538
perror_plus("Failed to raise privileges");
2539
} else {
2540
2541
/* Run network hooks */
2542
run_network_hooks("stop", interfaces_hooks != NULL ?
2543
interfaces_hooks : "", delay);
2544
2545
/* Take down the network interfaces which were brought up */
2546
{
2547
char *interface = NULL;
2548
while((interface=argz_next(interfaces_to_take_down,
2549
interfaces_to_take_down_size,
2550
interface))){
2551
ret_errno = take_down_interface(interface);
2552
if(ret_errno != 0){
2553
errno = ret_errno;
2554
perror_plus("Failed to take down interface");
2555
}
2556
}
2557
if(debug and (interfaces_to_take_down == NULL)){
2558
fprintf_plus(stderr, "No interfaces needed to be taken"
2559
" down\n");
2560
}
2561
}
2562
}
2563
ret_errno = lower_privileges_permanently();
2564
if(ret_errno != 0){
2565
perror_plus("Failed to lower privileges permanently");
2566
}
2567
}
2568
2569
free(interfaces_to_take_down);
2570
free(interfaces_hooks);
2571
2572
/* Removes the GPGME temp directory and all files inside */
2573
if(tempdir != NULL){
2574
struct dirent **direntries = NULL;
2575
struct dirent *direntry = NULL;
2576
int numentries = scandir(tempdir, &direntries, notdotentries,
2577
alphasort);
2578
if(numentries > 0){
2579
for(int i = 0; i < numentries; i++){
2580
direntry = direntries[i];
2581
char *fullname = NULL;
2582
ret = asprintf(&fullname, "%s/%s", tempdir,
2583
direntry->d_name);
2584
if(ret < 0){
2585
perror_plus("asprintf");
2586
continue;
2587
}
2588
ret = remove(fullname);
2589
if(ret == -1){
2590
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2591
strerror(errno));
2592
}
2593
free(fullname);
2594
}
2595
}
2596
2597
/* need to clean even if 0 because man page doesn't specify */
2598
free(direntries);
2599
if(numentries == -1){
2600
perror_plus("scandir");
2601
}
2602
ret = rmdir(tempdir);
2603
if(ret == -1 and errno != ENOENT){
2604
perror_plus("rmdir");
2605
}
2606
}
2607
2608
if(quit_now){
2609
sigemptyset(&old_sigterm_action.sa_mask);
2610
old_sigterm_action.sa_handler = SIG_DFL;
2611
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2612
&old_sigterm_action,
2613
NULL));
2614
if(ret == -1){
2615
perror_plus("sigaction");
2616
}
2617
do {
2618
ret = raise(signal_received);
2619
} while(ret != 0 and errno == EINTR);
2620
if(ret != 0){
2621
perror_plus("raise");
2622
abort();
2623
}
2624
TEMP_FAILURE_RETRY(pause());
2625
}
2626
2627
return exitcode;
2628
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0