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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 © 2008-2014 Teddy Hogeborn
13
* Copyright © 2008-2014 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
if(ret_errno != 0){
1719
perror_plus("Failed to raise privileges");
1720
}
1721
1722
#ifdef __linux__
1723
int ret_linux;
1724
bool restore_loglevel = false;
1725
if(ret_errno == 0){
1726
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1727
messages about the network interface to mess up the prompt */
1728
ret_linux = klogctl(8, NULL, 5);
1729
if(ret_linux == -1){
1730
perror_plus("klogctl");
1731
} else {
1732
restore_loglevel = true;
1733
}
1734
}
1735
#endif /* __linux__ */
1736
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1737
ioctl_errno = errno;
1738
#ifdef __linux__
1739
if(restore_loglevel){
1740
ret_linux = klogctl(7, NULL, 0);
1741
if(ret_linux == -1){
1742
perror_plus("klogctl");
1743
}
1744
}
1745
#endif /* __linux__ */
1746
1747
/* If raise_privileges() succeeded above */
1748
if(ret_errno == 0){
1749
/* Lower privileges */
1750
ret_errno = lower_privileges();
1751
if(ret_errno != 0){
1752
errno = ret_errno;
1753
perror_plus("Failed to lower privileges");
1754
}
1755
}
1756
1757
/* Close the socket */
1758
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1759
if(ret == -1){
1760
perror_plus("close");
1761
}
1762
1763
if(ret_setflags == -1){
1764
errno = ioctl_errno;
1765
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1766
errno = old_errno;
1767
return ioctl_errno;
1768
}
1769
} else if(debug){
1770
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1771
interface);
1772
}
1773
1774
/* Sleep checking until interface is running.
1775
Check every 0.25s, up to total time of delay */
1776
for(int i=0; i < delay * 4; i++){
1777
if(interface_is_running(interface)){
1778
break;
1779
}
1780
struct timespec sleeptime = { .tv_nsec = 250000000 };
1781
ret = nanosleep(&sleeptime, NULL);
1782
if(ret == -1 and errno != EINTR){
1783
perror_plus("nanosleep");
1784
}
1785
}
1786
1787
errno = old_errno;
1788
return 0;
1789
}
1790
1791
__attribute__((nonnull, warn_unused_result))
1792
error_t take_down_interface(const char *const interface){
1793
error_t old_errno = errno;
1794
struct ifreq network;
1795
unsigned int if_index = if_nametoindex(interface);
1796
if(if_index == 0){
1797
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1798
errno = old_errno;
1799
return ENXIO;
1800
}
1801
if(interface_is_up(interface)){
1802
error_t ret_errno = 0, ioctl_errno = 0;
1803
if(not get_flags(interface, &network) and debug){
1804
ret_errno = errno;
1805
fprintf_plus(stderr, "Failed to get flags for interface "
1806
"\"%s\"\n", interface);
1807
errno = old_errno;
1808
return ret_errno;
1809
}
1810
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1811
1812
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1813
if(sd == -1){
1814
ret_errno = errno;
1815
perror_plus("socket");
1816
errno = old_errno;
1817
return ret_errno;
1818
}
1819
1820
if(debug){
1821
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1822
interface);
1823
}
1824
1825
/* Raise privileges */
1826
ret_errno = raise_privileges();
1827
if(ret_errno != 0){
1828
perror_plus("Failed to raise privileges");
1829
}
1830
1831
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1832
ioctl_errno = errno;
1833
1834
/* If raise_privileges() succeeded above */
1835
if(ret_errno == 0){
1836
/* Lower privileges */
1837
ret_errno = lower_privileges();
1838
if(ret_errno != 0){
1839
errno = ret_errno;
1840
perror_plus("Failed to lower privileges");
1841
}
1842
}
1843
1844
/* Close the socket */
1845
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1846
if(ret == -1){
1847
perror_plus("close");
1848
}
1849
1850
if(ret_setflags == -1){
1851
errno = ioctl_errno;
1852
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1853
errno = old_errno;
1854
return ioctl_errno;
1855
}
1856
} else if(debug){
1857
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1858
interface);
1859
}
1860
1861
errno = old_errno;
1862
return 0;
1863
}
1864
1865
int main(int argc, char *argv[]){
1866
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1867
.priority = "SECURE256:!CTYPE-X.509:"
1868
"+CTYPE-OPENPGP", .current_server = NULL,
1869
.interfaces = NULL, .interfaces_size = 0 };
1870
AvahiSServiceBrowser *sb = NULL;
1871
error_t ret_errno;
1872
int ret;
1873
intmax_t tmpmax;
1874
char *tmp;
1875
int exitcode = EXIT_SUCCESS;
1876
char *interfaces_to_take_down = NULL;
1877
size_t interfaces_to_take_down_size = 0;
1878
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1879
char old_tempdir[] = "/tmp/mandosXXXXXX";
1880
char *tempdir = NULL;
1881
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1882
const char *seckey = PATHDIR "/" SECKEY;
1883
const char *pubkey = PATHDIR "/" PUBKEY;
1884
char *interfaces_hooks = NULL;
1885
1886
bool gnutls_initialized = false;
1887
bool gpgme_initialized = false;
1888
float delay = 2.5f;
1889
double retry_interval = 10; /* 10s between trying a server and
1890
retrying the same server again */
1891
1892
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1893
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1894
1895
uid = getuid();
1896
gid = getgid();
1897
1898
/* Lower any group privileges we might have, just to be safe */
1899
errno = 0;
1900
ret = setgid(gid);
1901
if(ret == -1){
1902
perror_plus("setgid");
1903
}
1904
1905
/* Lower user privileges (temporarily) */
1906
errno = 0;
1907
ret = seteuid(uid);
1908
if(ret == -1){
1909
perror_plus("seteuid");
1910
}
1911
1912
if(quit_now){
1913
goto end;
1914
}
1915
1916
{
1917
struct argp_option options[] = {
1918
{ .name = "debug", .key = 128,
1919
.doc = "Debug mode", .group = 3 },
1920
{ .name = "connect", .key = 'c',
1921
.arg = "ADDRESS:PORT",
1922
.doc = "Connect directly to a specific Mandos server",
1923
.group = 1 },
1924
{ .name = "interface", .key = 'i',
1925
.arg = "NAME",
1926
.doc = "Network interface that will be used to search for"
1927
" Mandos servers",
1928
.group = 1 },
1929
{ .name = "seckey", .key = 's',
1930
.arg = "FILE",
1931
.doc = "OpenPGP secret key file base name",
1932
.group = 1 },
1933
{ .name = "pubkey", .key = 'p',
1934
.arg = "FILE",
1935
.doc = "OpenPGP public key file base name",
1936
.group = 2 },
1937
{ .name = "dh-bits", .key = 129,
1938
.arg = "BITS",
1939
.doc = "Bit length of the prime number used in the"
1940
" Diffie-Hellman key exchange",
1941
.group = 2 },
1942
{ .name = "priority", .key = 130,
1943
.arg = "STRING",
1944
.doc = "GnuTLS priority string for the TLS handshake",
1945
.group = 1 },
1946
{ .name = "delay", .key = 131,
1947
.arg = "SECONDS",
1948
.doc = "Maximum delay to wait for interface startup",
1949
.group = 2 },
1950
{ .name = "retry", .key = 132,
1951
.arg = "SECONDS",
1952
.doc = "Retry interval used when denied by the Mandos server",
1953
.group = 2 },
1954
{ .name = "network-hook-dir", .key = 133,
1955
.arg = "DIR",
1956
.doc = "Directory where network hooks are located",
1957
.group = 2 },
1958
/*
1959
* These reproduce what we would get without ARGP_NO_HELP
1960
*/
1961
{ .name = "help", .key = '?',
1962
.doc = "Give this help list", .group = -1 },
1963
{ .name = "usage", .key = -3,
1964
.doc = "Give a short usage message", .group = -1 },
1965
{ .name = "version", .key = 'V',
1966
.doc = "Print program version", .group = -1 },
1967
{ .name = NULL }
1968
};
1969
1970
error_t parse_opt(int key, char *arg,
1971
struct argp_state *state){
1972
errno = 0;
1973
switch(key){
1974
case 128: /* --debug */
1975
debug = true;
1976
break;
1977
case 'c': /* --connect */
1978
connect_to = arg;
1979
break;
1980
case 'i': /* --interface */
1981
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1982
arg, (int)',');
1983
if(ret_errno != 0){
1984
argp_error(state, "%s", strerror(ret_errno));
1985
}
1986
break;
1987
case 's': /* --seckey */
1988
seckey = arg;
1989
break;
1990
case 'p': /* --pubkey */
1991
pubkey = arg;
1992
break;
1993
case 129: /* --dh-bits */
1994
errno = 0;
1995
tmpmax = strtoimax(arg, &tmp, 10);
1996
if(errno != 0 or tmp == arg or *tmp != '\0'
1997
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1998
argp_error(state, "Bad number of DH bits");
1999
}
2000
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2001
break;
2002
case 130: /* --priority */
2003
mc.priority = arg;
2004
break;
2005
case 131: /* --delay */
2006
errno = 0;
2007
delay = strtof(arg, &tmp);
2008
if(errno != 0 or tmp == arg or *tmp != '\0'){
2009
argp_error(state, "Bad delay");
2010
}
2011
case 132: /* --retry */
2012
errno = 0;
2013
retry_interval = strtod(arg, &tmp);
2014
if(errno != 0 or tmp == arg or *tmp != '\0'
2015
or (retry_interval * 1000) > INT_MAX
2016
or retry_interval < 0){
2017
argp_error(state, "Bad retry interval");
2018
}
2019
break;
2020
case 133: /* --network-hook-dir */
2021
hookdir = arg;
2022
break;
2023
/*
2024
* These reproduce what we would get without ARGP_NO_HELP
2025
*/
2026
case '?': /* --help */
2027
argp_state_help(state, state->out_stream,
2028
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2029
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2030
case -3: /* --usage */
2031
argp_state_help(state, state->out_stream,
2032
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2033
case 'V': /* --version */
2034
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2035
exit(argp_err_exit_status);
2036
break;
2037
default:
2038
return ARGP_ERR_UNKNOWN;
2039
}
2040
return errno;
2041
}
2042
2043
struct argp argp = { .options = options, .parser = parse_opt,
2044
.args_doc = "",
2045
.doc = "Mandos client -- Get and decrypt"
2046
" passwords from a Mandos server" };
2047
ret = argp_parse(&argp, argc, argv,
2048
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2049
switch(ret){
2050
case 0:
2051
break;
2052
case ENOMEM:
2053
default:
2054
errno = ret;
2055
perror_plus("argp_parse");
2056
exitcode = EX_OSERR;
2057
goto end;
2058
case EINVAL:
2059
exitcode = EX_USAGE;
2060
goto end;
2061
}
2062
}
2063
2064
{
2065
/* Work around Debian bug #633582:
2066
<http://bugs.debian.org/633582> */
2067
2068
/* Re-raise privileges */
2069
ret_errno = raise_privileges();
2070
if(ret_errno != 0){
2071
errno = ret_errno;
2072
perror_plus("Failed to raise privileges");
2073
} else {
2074
struct stat st;
2075
2076
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2077
int seckey_fd = open(seckey, O_RDONLY);
2078
if(seckey_fd == -1){
2079
perror_plus("open");
2080
} else {
2081
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2082
if(ret == -1){
2083
perror_plus("fstat");
2084
} else {
2085
if(S_ISREG(st.st_mode)
2086
and st.st_uid == 0 and st.st_gid == 0){
2087
ret = fchown(seckey_fd, uid, gid);
2088
if(ret == -1){
2089
perror_plus("fchown");
2090
}
2091
}
2092
}
2093
TEMP_FAILURE_RETRY(close(seckey_fd));
2094
}
2095
}
2096
2097
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2098
int pubkey_fd = open(pubkey, O_RDONLY);
2099
if(pubkey_fd == -1){
2100
perror_plus("open");
2101
} else {
2102
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2103
if(ret == -1){
2104
perror_plus("fstat");
2105
} else {
2106
if(S_ISREG(st.st_mode)
2107
and st.st_uid == 0 and st.st_gid == 0){
2108
ret = fchown(pubkey_fd, uid, gid);
2109
if(ret == -1){
2110
perror_plus("fchown");
2111
}
2112
}
2113
}
2114
TEMP_FAILURE_RETRY(close(pubkey_fd));
2115
}
2116
}
2117
2118
/* Lower privileges */
2119
ret_errno = lower_privileges();
2120
if(ret_errno != 0){
2121
errno = ret_errno;
2122
perror_plus("Failed to lower privileges");
2123
}
2124
}
2125
}
2126
2127
/* Remove invalid interface names (except "none") */
2128
{
2129
char *interface = NULL;
2130
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2131
interface))){
2132
if(strcmp(interface, "none") != 0
2133
and if_nametoindex(interface) == 0){
2134
if(interface[0] != '\0'){
2135
fprintf_plus(stderr, "Not using nonexisting interface"
2136
" \"%s\"\n", interface);
2137
}
2138
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2139
interface = NULL;
2140
}
2141
}
2142
}
2143
2144
/* Run network hooks */
2145
{
2146
if(mc.interfaces != NULL){
2147
interfaces_hooks = malloc(mc.interfaces_size);
2148
if(interfaces_hooks == NULL){
2149
perror_plus("malloc");
2150
goto end;
2151
}
2152
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2153
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2154
}
2155
run_network_hooks("start", interfaces_hooks != NULL ?
2156
interfaces_hooks : "", delay);
2157
}
2158
2159
if(not debug){
2160
avahi_set_log_function(empty_log);
2161
}
2162
2163
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2164
from the signal handler */
2165
/* Initialize the pseudo-RNG for Avahi */
2166
srand((unsigned int) time(NULL));
2167
simple_poll = avahi_simple_poll_new();
2168
if(simple_poll == NULL){
2169
fprintf_plus(stderr,
2170
"Avahi: Failed to create simple poll object.\n");
2171
exitcode = EX_UNAVAILABLE;
2172
goto end;
2173
}
2174
2175
sigemptyset(&sigterm_action.sa_mask);
2176
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2177
if(ret == -1){
2178
perror_plus("sigaddset");
2179
exitcode = EX_OSERR;
2180
goto end;
2181
}
2182
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2183
if(ret == -1){
2184
perror_plus("sigaddset");
2185
exitcode = EX_OSERR;
2186
goto end;
2187
}
2188
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2189
if(ret == -1){
2190
perror_plus("sigaddset");
2191
exitcode = EX_OSERR;
2192
goto end;
2193
}
2194
/* Need to check if the handler is SIG_IGN before handling:
2195
| [[info:libc:Initial Signal Actions]] |
2196
| [[info:libc:Basic Signal Handling]] |
2197
*/
2198
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2199
if(ret == -1){
2200
perror_plus("sigaction");
2201
return EX_OSERR;
2202
}
2203
if(old_sigterm_action.sa_handler != SIG_IGN){
2204
ret = sigaction(SIGINT, &sigterm_action, NULL);
2205
if(ret == -1){
2206
perror_plus("sigaction");
2207
exitcode = EX_OSERR;
2208
goto end;
2209
}
2210
}
2211
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2212
if(ret == -1){
2213
perror_plus("sigaction");
2214
return EX_OSERR;
2215
}
2216
if(old_sigterm_action.sa_handler != SIG_IGN){
2217
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2218
if(ret == -1){
2219
perror_plus("sigaction");
2220
exitcode = EX_OSERR;
2221
goto end;
2222
}
2223
}
2224
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2225
if(ret == -1){
2226
perror_plus("sigaction");
2227
return EX_OSERR;
2228
}
2229
if(old_sigterm_action.sa_handler != SIG_IGN){
2230
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2231
if(ret == -1){
2232
perror_plus("sigaction");
2233
exitcode = EX_OSERR;
2234
goto end;
2235
}
2236
}
2237
2238
/* If no interfaces were specified, make a list */
2239
if(mc.interfaces == NULL){
2240
struct dirent **direntries;
2241
/* Look for any good interfaces */
2242
ret = scandir(sys_class_net, &direntries, good_interface,
2243
alphasort);
2244
if(ret >= 1){
2245
/* Add all found interfaces to interfaces list */
2246
for(int i = 0; i < ret; ++i){
2247
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2248
direntries[i]->d_name);
2249
if(ret_errno != 0){
2250
errno = ret_errno;
2251
perror_plus("argz_add");
2252
continue;
2253
}
2254
if(debug){
2255
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2256
direntries[i]->d_name);
2257
}
2258
}
2259
free(direntries);
2260
} else {
2261
free(direntries);
2262
fprintf_plus(stderr, "Could not find a network interface\n");
2263
exitcode = EXIT_FAILURE;
2264
goto end;
2265
}
2266
}
2267
2268
/* Bring up interfaces which are down, and remove any "none"s */
2269
{
2270
char *interface = NULL;
2271
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2272
interface))){
2273
/* If interface name is "none", stop bringing up interfaces.
2274
Also remove all instances of "none" from the list */
2275
if(strcmp(interface, "none") == 0){
2276
argz_delete(&mc.interfaces, &mc.interfaces_size,
2277
interface);
2278
interface = NULL;
2279
while((interface = argz_next(mc.interfaces,
2280
mc.interfaces_size, interface))){
2281
if(strcmp(interface, "none") == 0){
2282
argz_delete(&mc.interfaces, &mc.interfaces_size,
2283
interface);
2284
interface = NULL;
2285
}
2286
}
2287
break;
2288
}
2289
bool interface_was_up = interface_is_up(interface);
2290
errno = bring_up_interface(interface, delay);
2291
if(not interface_was_up){
2292
if(errno != 0){
2293
perror_plus("Failed to bring up interface");
2294
} else {
2295
errno = argz_add(&interfaces_to_take_down,
2296
&interfaces_to_take_down_size,
2297
interface);
2298
if(errno != 0){
2299
perror_plus("argz_add");
2300
}
2301
}
2302
}
2303
}
2304
if(debug and (interfaces_to_take_down == NULL)){
2305
fprintf_plus(stderr, "No interfaces were brought up\n");
2306
}
2307
}
2308
2309
/* If we only got one interface, explicitly use only that one */
2310
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2311
if(debug){
2312
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2313
mc.interfaces);
2314
}
2315
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2316
}
2317
2318
if(quit_now){
2319
goto end;
2320
}
2321
2322
ret = init_gnutls_global(pubkey, seckey, &mc);
2323
if(ret == -1){
2324
fprintf_plus(stderr, "init_gnutls_global failed\n");
2325
exitcode = EX_UNAVAILABLE;
2326
goto end;
2327
} else {
2328
gnutls_initialized = true;
2329
}
2330
2331
if(quit_now){
2332
goto end;
2333
}
2334
2335
/* Try /run/tmp before /tmp */
2336
tempdir = mkdtemp(run_tempdir);
2337
if(tempdir == NULL and errno == ENOENT){
2338
if(debug){
2339
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2340
run_tempdir, old_tempdir);
2341
}
2342
tempdir = mkdtemp(old_tempdir);
2343
}
2344
if(tempdir == NULL){
2345
perror_plus("mkdtemp");
2346
goto end;
2347
}
2348
2349
if(quit_now){
2350
goto end;
2351
}
2352
2353
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2354
fprintf_plus(stderr, "init_gpgme failed\n");
2355
exitcode = EX_UNAVAILABLE;
2356
goto end;
2357
} else {
2358
gpgme_initialized = true;
2359
}
2360
2361
if(quit_now){
2362
goto end;
2363
}
2364
2365
if(connect_to != NULL){
2366
/* Connect directly, do not use Zeroconf */
2367
/* (Mainly meant for debugging) */
2368
char *address = strrchr(connect_to, ':');
2369
2370
if(address == NULL){
2371
fprintf_plus(stderr, "No colon in address\n");
2372
exitcode = EX_USAGE;
2373
goto end;
2374
}
2375
2376
if(quit_now){
2377
goto end;
2378
}
2379
2380
in_port_t port;
2381
errno = 0;
2382
tmpmax = strtoimax(address+1, &tmp, 10);
2383
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2384
or tmpmax != (in_port_t)tmpmax){
2385
fprintf_plus(stderr, "Bad port number\n");
2386
exitcode = EX_USAGE;
2387
goto end;
2388
}
2389
2390
if(quit_now){
2391
goto end;
2392
}
2393
2394
port = (in_port_t)tmpmax;
2395
*address = '\0';
2396
/* Colon in address indicates IPv6 */
2397
int af;
2398
if(strchr(connect_to, ':') != NULL){
2399
af = AF_INET6;
2400
/* Accept [] around IPv6 address - see RFC 5952 */
2401
if(connect_to[0] == '[' and address[-1] == ']')
2402
{
2403
connect_to++;
2404
address[-1] = '\0';
2405
}
2406
} else {
2407
af = AF_INET;
2408
}
2409
address = connect_to;
2410
2411
if(quit_now){
2412
goto end;
2413
}
2414
2415
while(not quit_now){
2416
ret = start_mandos_communication(address, port, if_index, af,
2417
&mc);
2418
if(quit_now or ret == 0){
2419
break;
2420
}
2421
if(debug){
2422
fprintf_plus(stderr, "Retrying in %d seconds\n",
2423
(int)retry_interval);
2424
}
2425
sleep((unsigned int)retry_interval);
2426
}
2427
2428
if(not quit_now){
2429
exitcode = EXIT_SUCCESS;
2430
}
2431
2432
goto end;
2433
}
2434
2435
if(quit_now){
2436
goto end;
2437
}
2438
2439
{
2440
AvahiServerConfig config;
2441
/* Do not publish any local Zeroconf records */
2442
avahi_server_config_init(&config);
2443
config.publish_hinfo = 0;
2444
config.publish_addresses = 0;
2445
config.publish_workstation = 0;
2446
config.publish_domain = 0;
2447
2448
/* Allocate a new server */
2449
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2450
&config, NULL, NULL, &ret_errno);
2451
2452
/* Free the Avahi configuration data */
2453
avahi_server_config_free(&config);
2454
}
2455
2456
/* Check if creating the Avahi server object succeeded */
2457
if(mc.server == NULL){
2458
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2459
avahi_strerror(ret_errno));
2460
exitcode = EX_UNAVAILABLE;
2461
goto end;
2462
}
2463
2464
if(quit_now){
2465
goto end;
2466
}
2467
2468
/* Create the Avahi service browser */
2469
sb = avahi_s_service_browser_new(mc.server, if_index,
2470
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2471
NULL, 0, browse_callback,
2472
(void *)&mc);
2473
if(sb == NULL){
2474
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2475
avahi_strerror(avahi_server_errno(mc.server)));
2476
exitcode = EX_UNAVAILABLE;
2477
goto end;
2478
}
2479
2480
if(quit_now){
2481
goto end;
2482
}
2483
2484
/* Run the main loop */
2485
2486
if(debug){
2487
fprintf_plus(stderr, "Starting Avahi loop search\n");
2488
}
2489
2490
ret = avahi_loop_with_timeout(simple_poll,
2491
(int)(retry_interval * 1000), &mc);
2492
if(debug){
2493
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2494
(ret == 0) ? "successfully" : "with error");
2495
}
2496
2497
end:
2498
2499
if(debug){
2500
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2501
}
2502
2503
/* Cleanup things */
2504
free(mc.interfaces);
2505
2506
if(sb != NULL)
2507
avahi_s_service_browser_free(sb);
2508
2509
if(mc.server != NULL)
2510
avahi_server_free(mc.server);
2511
2512
if(simple_poll != NULL)
2513
avahi_simple_poll_free(simple_poll);
2514
2515
if(gnutls_initialized){
2516
gnutls_certificate_free_credentials(mc.cred);
2517
gnutls_global_deinit();
2518
gnutls_dh_params_deinit(mc.dh_params);
2519
}
2520
2521
if(gpgme_initialized){
2522
gpgme_release(mc.ctx);
2523
}
2524
2525
/* Cleans up the circular linked list of Mandos servers the client
2526
has seen */
2527
if(mc.current_server != NULL){
2528
mc.current_server->prev->next = NULL;
2529
while(mc.current_server != NULL){
2530
server *next = mc.current_server->next;
2531
free(mc.current_server);
2532
mc.current_server = next;
2533
}
2534
}
2535
2536
/* Re-raise privileges */
2537
{
2538
ret_errno = raise_privileges();
2539
if(ret_errno != 0){
2540
perror_plus("Failed to raise privileges");
2541
} else {
2542
2543
/* Run network hooks */
2544
run_network_hooks("stop", interfaces_hooks != NULL ?
2545
interfaces_hooks : "", delay);
2546
2547
/* Take down the network interfaces which were brought up */
2548
{
2549
char *interface = NULL;
2550
while((interface=argz_next(interfaces_to_take_down,
2551
interfaces_to_take_down_size,
2552
interface))){
2553
ret_errno = take_down_interface(interface);
2554
if(ret_errno != 0){
2555
errno = ret_errno;
2556
perror_plus("Failed to take down interface");
2557
}
2558
}
2559
if(debug and (interfaces_to_take_down == NULL)){
2560
fprintf_plus(stderr, "No interfaces needed to be taken"
2561
" down\n");
2562
}
2563
}
2564
}
2565
2566
ret_errno = lower_privileges_permanently();
2567
if(ret_errno != 0){
2568
perror_plus("Failed to lower privileges permanently");
2569
}
2570
}
2571
2572
free(interfaces_to_take_down);
2573
free(interfaces_hooks);
2574
2575
/* Removes the GPGME temp directory and all files inside */
2576
if(tempdir != NULL){
2577
struct dirent **direntries = NULL;
2578
struct dirent *direntry = NULL;
2579
int numentries = scandir(tempdir, &direntries, notdotentries,
2580
alphasort);
2581
if(numentries > 0){
2582
for(int i = 0; i < numentries; i++){
2583
direntry = direntries[i];
2584
char *fullname = NULL;
2585
ret = asprintf(&fullname, "%s/%s", tempdir,
2586
direntry->d_name);
2587
if(ret < 0){
2588
perror_plus("asprintf");
2589
continue;
2590
}
2591
ret = remove(fullname);
2592
if(ret == -1){
2593
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2594
strerror(errno));
2595
}
2596
free(fullname);
2597
}
2598
}
2599
2600
/* need to clean even if 0 because man page doesn't specify */
2601
free(direntries);
2602
if(numentries == -1){
2603
perror_plus("scandir");
2604
}
2605
ret = rmdir(tempdir);
2606
if(ret == -1 and errno != ENOENT){
2607
perror_plus("rmdir");
2608
}
2609
}
2610
2611
if(quit_now){
2612
sigemptyset(&old_sigterm_action.sa_mask);
2613
old_sigterm_action.sa_handler = SIG_DFL;
2614
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2615
&old_sigterm_action,
2616
NULL));
2617
if(ret == -1){
2618
perror_plus("sigaction");
2619
}
2620
do {
2621
ret = raise(signal_received);
2622
} while(ret != 0 and errno == EINTR);
2623
if(ret != 0){
2624
perror_plus("raise");
2625
abort();
2626
}
2627
TEMP_FAILURE_RETRY(pause());
2628
}
2629
2630
return exitcode;
2631
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0