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- Committer: Teddy Hogeborn
- Date: 2008-01-19 04:09:06 UTC
- Revision ID: teddy@fukt.bsnet.se-20080119040906-yjriaiqxbvzb93mq
* Makefile (client_debug): Bug fix; add quotes and / to CERT_ROOT.
* server.py (cred): Removed; no need for a global variable.
* server.py (cred): Removed; no need for a global variable.
- 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 /* not _LARGEFILE_SOURCE */
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
38
#endif /* not _FILE_OFFSET_BITS */
39
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror() */
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(), unlinkat() */
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
unlinkat() */
78
#include <arpa/inet.h> /* inet_pton(), htons() */
79
#include <iso646.h> /* not, or, and */
80
#include <argp.h> /* struct argp_option, error_t, struct
81
argp_state, struct argp,
82
argp_parse(), ARGP_KEY_ARG,
83
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
84
#include <signal.h> /* sigemptyset(), sigaddset(),
85
sigaction(), SIGTERM, sig_atomic_t,
86
raise() */
87
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
88
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
90
WEXITSTATUS(), WTERMSIG() */
91
#include <grp.h> /* setgroups() */
92
#include <argz.h> /* argz_add_sep(), argz_next(),
93
argz_delete(), argz_append(),
94
argz_stringify(), argz_add(),
95
argz_count() */
96
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
97
EAI_SYSTEM, gai_strerror() */
98
99
#ifdef __linux__
100
#include <sys/klog.h> /* klogctl() */
101
#endif /* __linux__ */
102
103
/* Avahi */
104
/* All Avahi types, constants and functions
105
Avahi*, avahi_*,
106
AVAHI_* */
107
#include <avahi-core/core.h>
108
#include <avahi-core/lookup.h>
109
#include <avahi-core/log.h>
110
#include <avahi-common/simple-watch.h>
111
#include <avahi-common/malloc.h>
112
#include <avahi-common/error.h>
113
114
/* GnuTLS */
115
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
116
functions:
117
gnutls_*
118
init_gnutls_session(),
119
GNUTLS_* */
120
#include <gnutls/openpgp.h>
121
/* gnutls_certificate_set_openpgp_key_file(),
122
GNUTLS_OPENPGP_FMT_BASE64 */
123
124
/* GPGME */
125
#include <gpgme.h> /* All GPGME types, constants and
126
functions:
127
gpgme_*
128
GPGME_PROTOCOL_OpenPGP,
129
GPG_ERR_NO_* */
130
131
#define BUFFER_SIZE 256
132
133
#define PATHDIR "/conf/conf.d/mandos"
134
#define SECKEY "seckey.txt"
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
137
138
bool debug = false;
139
static const char mandos_protocol_version[] = "1";
140
const char *argp_program_version = "mandos-client " VERSION;
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
142
static const char sys_class_net[] = "/sys/class/net";
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
145
int hookdir_fd = -1;
146
uid_t uid = 65534;
147
gid_t gid = 65534;
148
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
151
const char *ip;
152
in_port_t port;
153
AvahiIfIndex if_index;
154
int af;
155
struct timespec last_seen;
156
struct server *next;
157
struct server *prev;
158
} server;
159
160
/* Used for passing in values through the Avahi callback functions */
161
typedef struct {
162
AvahiServer *server;
163
gnutls_certificate_credentials_t cred;
164
unsigned int dh_bits;
165
gnutls_dh_params_t dh_params;
166
const char *priority;
167
gpgme_ctx_t ctx;
168
server *current_server;
169
char *interfaces;
170
size_t interfaces_size;
171
} mandos_context;
172
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
175
176
sig_atomic_t quit_now = 0;
177
int signal_received = 0;
178
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
181
int e = errno;
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
184
errno = e;
185
perror(print_text);
186
}
187
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
190
va_list ap;
191
va_start (ap, format);
192
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
196
}
197
198
/*
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
200
* bytes. "buffer_capacity" is how much is currently allocated,
201
* "buffer_length" is how much is already used.
202
*/
203
__attribute__((nonnull, warn_unused_result))
204
size_t incbuffer(char **buffer, size_t buffer_length,
205
size_t buffer_capacity){
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
208
if(new_buf == NULL){
209
int old_errno = errno;
210
free(*buffer);
211
errno = old_errno;
212
*buffer = NULL;
213
return 0;
214
}
215
*buffer = new_buf;
216
buffer_capacity += BUFFER_SIZE;
217
}
218
return buffer_capacity;
219
}
220
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
225
int ret;
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
229
return false;
230
}
231
*new_server = (server){ .ip = strdup(ip),
232
.port = port,
233
.if_index = if_index,
234
.af = af };
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
237
free(new_server);
238
return false;
239
}
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
241
if(ret == -1){
242
perror_plus("clock_gettime");
243
#ifdef __GNUC__
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
246
#endif
247
free((char *)(new_server->ip));
248
#ifdef __GNUC__
249
#pragma GCC diagnostic pop
250
#endif
251
free(new_server);
252
return false;
253
}
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
259
} else {
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
265
}
266
return true;
267
}
268
269
/*
270
* Initialize GPGME.
271
*/
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
276
mandos_context *mc){
277
gpgme_error_t rc;
278
gpgme_engine_info_t engine_info;
279
280
/*
281
* Helper function to insert pub and seckey to the engine keyring.
282
*/
283
bool import_key(const char * const filename){
284
int ret;
285
int fd;
286
gpgme_data_t pgp_data;
287
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
289
if(fd == -1){
290
perror_plus("open");
291
return false;
292
}
293
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
295
if(rc != GPG_ERR_NO_ERROR){
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
298
return false;
299
}
300
301
rc = gpgme_op_import(mc->ctx, pgp_data);
302
if(rc != GPG_ERR_NO_ERROR){
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
305
return false;
306
}
307
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
309
if(ret == -1){
310
perror_plus("close");
311
}
312
gpgme_data_release(pgp_data);
313
return true;
314
}
315
316
if(debug){
317
fprintf_plus(stderr, "Initializing GPGME\n");
318
}
319
320
/* Init GPGME */
321
gpgme_check_version(NULL);
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
323
if(rc != GPG_ERR_NO_ERROR){
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
326
return false;
327
}
328
329
/* Set GPGME home directory for the OpenPGP engine only */
330
rc = gpgme_get_engine_info(&engine_info);
331
if(rc != GPG_ERR_NO_ERROR){
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
gpgme_strsource(rc), gpgme_strerror(rc));
334
return false;
335
}
336
while(engine_info != NULL){
337
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
338
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
339
engine_info->file_name, tempdir);
340
break;
341
}
342
engine_info = engine_info->next;
343
}
344
if(engine_info == NULL){
345
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
346
tempdir);
347
return false;
348
}
349
350
/* Create new GPGME "context" */
351
rc = gpgme_new(&(mc->ctx));
352
if(rc != GPG_ERR_NO_ERROR){
353
fprintf_plus(stderr, "Mandos plugin mandos-client: "
354
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
355
gpgme_strerror(rc));
356
return false;
357
}
358
359
if(not import_key(pubkey) or not import_key(seckey)){
360
return false;
361
}
362
363
return true;
364
}
365
366
/*
367
* Decrypt OpenPGP data.
368
* Returns -1 on error
369
*/
370
__attribute__((nonnull, warn_unused_result))
371
static ssize_t pgp_packet_decrypt(const char *cryptotext,
372
size_t crypto_size,
373
char **plaintext,
374
mandos_context *mc){
375
gpgme_data_t dh_crypto, dh_plain;
376
gpgme_error_t rc;
377
ssize_t ret;
378
size_t plaintext_capacity = 0;
379
ssize_t plaintext_length = 0;
380
381
if(debug){
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
383
}
384
385
/* Create new GPGME data buffer from memory cryptotext */
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
387
0);
388
if(rc != GPG_ERR_NO_ERROR){
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
391
return -1;
392
}
393
394
/* Create new empty GPGME data buffer for the plaintext */
395
rc = gpgme_data_new(&dh_plain);
396
if(rc != GPG_ERR_NO_ERROR){
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
400
gpgme_data_release(dh_crypto);
401
return -1;
402
}
403
404
/* Decrypt data from the cryptotext data buffer to the plaintext
405
data buffer */
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
407
if(rc != GPG_ERR_NO_ERROR){
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
410
plaintext_length = -1;
411
if(debug){
412
gpgme_decrypt_result_t result;
413
result = gpgme_op_decrypt_result(mc->ctx);
414
if(result == NULL){
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
416
} else {
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
421
if(result->file_name != NULL){
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
423
}
424
gpgme_recipient_t recipient;
425
recipient = result->recipients;
426
while(recipient != NULL){
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
433
? "No" : "Yes");
434
recipient = recipient->next;
435
}
436
}
437
}
438
goto decrypt_end;
439
}
440
441
if(debug){
442
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
443
}
444
445
/* Seek back to the beginning of the GPGME plaintext data buffer */
446
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
447
perror_plus("gpgme_data_seek");
448
plaintext_length = -1;
449
goto decrypt_end;
450
}
451
452
*plaintext = NULL;
453
while(true){
454
plaintext_capacity = incbuffer(plaintext,
455
(size_t)plaintext_length,
456
plaintext_capacity);
457
if(plaintext_capacity == 0){
458
perror_plus("incbuffer");
459
plaintext_length = -1;
460
goto decrypt_end;
461
}
462
463
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
464
BUFFER_SIZE);
465
/* Print the data, if any */
466
if(ret == 0){
467
/* EOF */
468
break;
469
}
470
if(ret < 0){
471
perror_plus("gpgme_data_read");
472
plaintext_length = -1;
473
goto decrypt_end;
474
}
475
plaintext_length += ret;
476
}
477
478
if(debug){
479
fprintf_plus(stderr, "Decrypted password is: ");
480
for(ssize_t i = 0; i < plaintext_length; i++){
481
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
482
}
483
fprintf(stderr, "\n");
484
}
485
486
decrypt_end:
487
488
/* Delete the GPGME cryptotext data buffer */
489
gpgme_data_release(dh_crypto);
490
491
/* Delete the GPGME plaintext data buffer */
492
gpgme_data_release(dh_plain);
493
return plaintext_length;
494
}
495
496
__attribute__((warn_unused_result))
497
static const char *safer_gnutls_strerror(int value){
498
const char *ret = gnutls_strerror(value);
499
if(ret == NULL)
500
ret = "(unknown)";
501
return ret;
502
}
503
504
/* GnuTLS log function callback */
505
__attribute__((nonnull))
506
static void debuggnutls(__attribute__((unused)) int level,
507
const char* string){
508
fprintf_plus(stderr, "GnuTLS: %s", string);
509
}
510
511
__attribute__((nonnull, warn_unused_result))
512
static int init_gnutls_global(const char *pubkeyfilename,
513
const char *seckeyfilename,
514
mandos_context *mc){
515
int ret;
516
517
if(debug){
518
fprintf_plus(stderr, "Initializing GnuTLS\n");
519
}
520
521
ret = gnutls_global_init();
522
if(ret != GNUTLS_E_SUCCESS){
523
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
524
safer_gnutls_strerror(ret));
525
return -1;
526
}
527
528
if(debug){
529
/* "Use a log level over 10 to enable all debugging options."
530
* - GnuTLS manual
531
*/
532
gnutls_global_set_log_level(11);
533
gnutls_global_set_log_function(debuggnutls);
534
}
535
536
/* OpenPGP credentials */
537
ret = gnutls_certificate_allocate_credentials(&mc->cred);
538
if(ret != GNUTLS_E_SUCCESS){
539
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
540
safer_gnutls_strerror(ret));
541
gnutls_global_deinit();
542
return -1;
543
}
544
545
if(debug){
546
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
547
" secret key %s as GnuTLS credentials\n",
548
pubkeyfilename,
549
seckeyfilename);
550
}
551
552
ret = gnutls_certificate_set_openpgp_key_file
553
(mc->cred, pubkeyfilename, seckeyfilename,
554
GNUTLS_OPENPGP_FMT_BASE64);
555
if(ret != GNUTLS_E_SUCCESS){
556
fprintf_plus(stderr,
557
"Error[%d] while reading the OpenPGP key pair ('%s',"
558
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
559
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
560
safer_gnutls_strerror(ret));
561
goto globalfail;
562
}
563
564
/* GnuTLS server initialization */
565
ret = gnutls_dh_params_init(&mc->dh_params);
566
if(ret != GNUTLS_E_SUCCESS){
567
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
568
" initialization: %s\n",
569
safer_gnutls_strerror(ret));
570
goto globalfail;
571
}
572
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
575
safer_gnutls_strerror(ret));
576
goto globalfail;
577
}
578
579
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
580
581
return 0;
582
583
globalfail:
584
585
gnutls_certificate_free_credentials(mc->cred);
586
gnutls_global_deinit();
587
gnutls_dh_params_deinit(mc->dh_params);
588
return -1;
589
}
590
591
__attribute__((nonnull, warn_unused_result))
592
static int init_gnutls_session(gnutls_session_t *session,
593
mandos_context *mc){
594
int ret;
595
/* GnuTLS session creation */
596
do {
597
ret = gnutls_init(session, GNUTLS_SERVER);
598
if(quit_now){
599
return -1;
600
}
601
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
602
if(ret != GNUTLS_E_SUCCESS){
603
fprintf_plus(stderr,
604
"Error in GnuTLS session initialization: %s\n",
605
safer_gnutls_strerror(ret));
606
}
607
608
{
609
const char *err;
610
do {
611
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
612
if(quit_now){
613
gnutls_deinit(*session);
614
return -1;
615
}
616
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
617
if(ret != GNUTLS_E_SUCCESS){
618
fprintf_plus(stderr, "Syntax error at: %s\n", err);
619
fprintf_plus(stderr, "GnuTLS error: %s\n",
620
safer_gnutls_strerror(ret));
621
gnutls_deinit(*session);
622
return -1;
623
}
624
}
625
626
do {
627
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
628
mc->cred);
629
if(quit_now){
630
gnutls_deinit(*session);
631
return -1;
632
}
633
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
634
if(ret != GNUTLS_E_SUCCESS){
635
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
636
safer_gnutls_strerror(ret));
637
gnutls_deinit(*session);
638
return -1;
639
}
640
641
/* ignore client certificate if any. */
642
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
643
644
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
645
646
return 0;
647
}
648
649
/* Avahi log function callback */
650
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
651
__attribute__((unused)) const char *txt){}
652
653
/* Called when a Mandos server is found */
654
__attribute__((nonnull, warn_unused_result))
655
static int start_mandos_communication(const char *ip, in_port_t port,
656
AvahiIfIndex if_index,
657
int af, mandos_context *mc){
658
int ret, tcp_sd = -1;
659
ssize_t sret;
660
struct sockaddr_storage to;
661
char *buffer = NULL;
662
char *decrypted_buffer = NULL;
663
size_t buffer_length = 0;
664
size_t buffer_capacity = 0;
665
size_t written;
666
int retval = -1;
667
gnutls_session_t session;
668
int pf; /* Protocol family */
669
670
errno = 0;
671
672
if(quit_now){
673
errno = EINTR;
674
return -1;
675
}
676
677
switch(af){
678
case AF_INET6:
679
pf = PF_INET6;
680
break;
681
case AF_INET:
682
pf = PF_INET;
683
break;
684
default:
685
fprintf_plus(stderr, "Bad address family: %d\n", af);
686
errno = EINVAL;
687
return -1;
688
}
689
690
/* If the interface is specified and we have a list of interfaces */
691
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
692
/* Check if the interface is one of the interfaces we are using */
693
bool match = false;
694
{
695
char *interface = NULL;
696
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
697
interface))){
698
if(if_nametoindex(interface) == (unsigned int)if_index){
699
match = true;
700
break;
701
}
702
}
703
}
704
if(not match){
705
/* This interface does not match any in the list, so we don't
706
connect to the server */
707
if(debug){
708
char interface[IF_NAMESIZE];
709
if(if_indextoname((unsigned int)if_index, interface) == NULL){
710
perror_plus("if_indextoname");
711
} else {
712
fprintf_plus(stderr, "Skipping server on non-used interface"
713
" \"%s\"\n",
714
if_indextoname((unsigned int)if_index,
715
interface));
716
}
717
}
718
return -1;
719
}
720
}
721
722
ret = init_gnutls_session(&session, mc);
723
if(ret != 0){
724
return -1;
725
}
726
727
if(debug){
728
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
729
PRIuMAX "\n", ip, (uintmax_t)port);
730
}
731
732
tcp_sd = socket(pf, SOCK_STREAM, 0);
733
if(tcp_sd < 0){
734
int e = errno;
735
perror_plus("socket");
736
errno = e;
737
goto mandos_end;
738
}
739
740
if(quit_now){
741
errno = EINTR;
742
goto mandos_end;
743
}
744
745
memset(&to, 0, sizeof(to));
746
if(af == AF_INET6){
747
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
748
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
749
} else { /* IPv4 */
750
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
751
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
752
}
753
if(ret < 0 ){
754
int e = errno;
755
perror_plus("inet_pton");
756
errno = e;
757
goto mandos_end;
758
}
759
if(ret == 0){
760
int e = errno;
761
fprintf_plus(stderr, "Bad address: %s\n", ip);
762
errno = e;
763
goto mandos_end;
764
}
765
if(af == AF_INET6){
766
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
767
if(IN6_IS_ADDR_LINKLOCAL
768
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
769
if(if_index == AVAHI_IF_UNSPEC){
770
fprintf_plus(stderr, "An IPv6 link-local address is"
771
" incomplete without a network interface\n");
772
errno = EINVAL;
773
goto mandos_end;
774
}
775
/* Set the network interface number as scope */
776
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
777
}
778
} else {
779
((struct sockaddr_in *)&to)->sin_port = htons(port);
780
}
781
782
if(quit_now){
783
errno = EINTR;
784
goto mandos_end;
785
}
786
787
if(debug){
788
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
789
char interface[IF_NAMESIZE];
790
if(if_indextoname((unsigned int)if_index, interface) == NULL){
791
perror_plus("if_indextoname");
792
} else {
793
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
794
"\n", ip, interface, (uintmax_t)port);
795
}
796
} else {
797
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
798
ip, (uintmax_t)port);
799
}
800
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
801
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
802
if(af == AF_INET6){
803
ret = getnameinfo((struct sockaddr *)&to,
804
sizeof(struct sockaddr_in6),
805
addrstr, sizeof(addrstr), NULL, 0,
806
NI_NUMERICHOST);
807
} else {
808
ret = getnameinfo((struct sockaddr *)&to,
809
sizeof(struct sockaddr_in),
810
addrstr, sizeof(addrstr), NULL, 0,
811
NI_NUMERICHOST);
812
}
813
if(ret == EAI_SYSTEM){
814
perror_plus("getnameinfo");
815
} else if(ret != 0) {
816
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
817
} else if(strcmp(addrstr, ip) != 0){
818
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
819
}
820
}
821
822
if(quit_now){
823
errno = EINTR;
824
goto mandos_end;
825
}
826
827
if(af == AF_INET6){
828
ret = connect(tcp_sd, (struct sockaddr *)&to,
829
sizeof(struct sockaddr_in6));
830
} else {
831
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
832
sizeof(struct sockaddr_in));
833
}
834
if(ret < 0){
835
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
836
int e = errno;
837
perror_plus("connect");
838
errno = e;
839
}
840
goto mandos_end;
841
}
842
843
if(quit_now){
844
errno = EINTR;
845
goto mandos_end;
846
}
847
848
const char *out = mandos_protocol_version;
849
written = 0;
850
while(true){
851
size_t out_size = strlen(out);
852
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
853
out_size - written));
854
if(ret == -1){
855
int e = errno;
856
perror_plus("write");
857
errno = e;
858
goto mandos_end;
859
}
860
written += (size_t)ret;
861
if(written < out_size){
862
continue;
863
} else {
864
if(out == mandos_protocol_version){
865
written = 0;
866
out = "\r\n";
867
} else {
868
break;
869
}
870
}
871
872
if(quit_now){
873
errno = EINTR;
874
goto mandos_end;
875
}
876
}
877
878
if(debug){
879
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
880
}
881
882
if(quit_now){
883
errno = EINTR;
884
goto mandos_end;
885
}
886
887
/* This casting via intptr_t is to eliminate warning about casting
888
an int to a pointer type. This is exactly how the GnuTLS Guile
889
function "set-session-transport-fd!" does it. */
890
gnutls_transport_set_ptr(session,
891
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
892
893
if(quit_now){
894
errno = EINTR;
895
goto mandos_end;
896
}
897
898
do {
899
ret = gnutls_handshake(session);
900
if(quit_now){
901
errno = EINTR;
902
goto mandos_end;
903
}
904
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
905
906
if(ret != GNUTLS_E_SUCCESS){
907
if(debug){
908
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
909
gnutls_perror(ret);
910
}
911
errno = EPROTO;
912
goto mandos_end;
913
}
914
915
/* Read OpenPGP packet that contains the wanted password */
916
917
if(debug){
918
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
919
" %s\n", ip);
920
}
921
922
while(true){
923
924
if(quit_now){
925
errno = EINTR;
926
goto mandos_end;
927
}
928
929
buffer_capacity = incbuffer(&buffer, buffer_length,
930
buffer_capacity);
931
if(buffer_capacity == 0){
932
int e = errno;
933
perror_plus("incbuffer");
934
errno = e;
935
goto mandos_end;
936
}
937
938
if(quit_now){
939
errno = EINTR;
940
goto mandos_end;
941
}
942
943
sret = gnutls_record_recv(session, buffer+buffer_length,
944
BUFFER_SIZE);
945
if(sret == 0){
946
break;
947
}
948
if(sret < 0){
949
switch(sret){
950
case GNUTLS_E_INTERRUPTED:
951
case GNUTLS_E_AGAIN:
952
break;
953
case GNUTLS_E_REHANDSHAKE:
954
do {
955
ret = gnutls_handshake(session);
956
957
if(quit_now){
958
errno = EINTR;
959
goto mandos_end;
960
}
961
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
962
if(ret < 0){
963
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
964
"***\n");
965
gnutls_perror(ret);
966
errno = EPROTO;
967
goto mandos_end;
968
}
969
break;
970
default:
971
fprintf_plus(stderr, "Unknown error while reading data from"
972
" encrypted session with Mandos server\n");
973
gnutls_bye(session, GNUTLS_SHUT_RDWR);
974
errno = EIO;
975
goto mandos_end;
976
}
977
} else {
978
buffer_length += (size_t) sret;
979
}
980
}
981
982
if(debug){
983
fprintf_plus(stderr, "Closing TLS session\n");
984
}
985
986
if(quit_now){
987
errno = EINTR;
988
goto mandos_end;
989
}
990
991
do {
992
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
993
if(quit_now){
994
errno = EINTR;
995
goto mandos_end;
996
}
997
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
998
999
if(buffer_length > 0){
1000
ssize_t decrypted_buffer_size;
1001
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1002
&decrypted_buffer, mc);
1003
if(decrypted_buffer_size >= 0){
1004
1005
written = 0;
1006
while(written < (size_t) decrypted_buffer_size){
1007
if(quit_now){
1008
errno = EINTR;
1009
goto mandos_end;
1010
}
1011
1012
ret = (int)fwrite(decrypted_buffer + written, 1,
1013
(size_t)decrypted_buffer_size - written,
1014
stdout);
1015
if(ret == 0 and ferror(stdout)){
1016
int e = errno;
1017
if(debug){
1018
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1019
strerror(errno));
1020
}
1021
errno = e;
1022
goto mandos_end;
1023
}
1024
written += (size_t)ret;
1025
}
1026
retval = 0;
1027
}
1028
}
1029
1030
/* Shutdown procedure */
1031
1032
mandos_end:
1033
{
1034
int e = errno;
1035
free(decrypted_buffer);
1036
free(buffer);
1037
if(tcp_sd >= 0){
1038
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1039
}
1040
if(ret == -1){
1041
if(e == 0){
1042
e = errno;
1043
}
1044
perror_plus("close");
1045
}
1046
gnutls_deinit(session);
1047
errno = e;
1048
if(quit_now){
1049
errno = EINTR;
1050
retval = -1;
1051
}
1052
}
1053
return retval;
1054
}
1055
1056
__attribute__((nonnull))
1057
static void resolve_callback(AvahiSServiceResolver *r,
1058
AvahiIfIndex interface,
1059
AvahiProtocol proto,
1060
AvahiResolverEvent event,
1061
const char *name,
1062
const char *type,
1063
const char *domain,
1064
const char *host_name,
1065
const AvahiAddress *address,
1066
uint16_t port,
1067
AVAHI_GCC_UNUSED AvahiStringList *txt,
1068
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1069
flags,
1070
void *mc){
1071
if(r == NULL){
1072
return;
1073
}
1074
1075
/* Called whenever a service has been resolved successfully or
1076
timed out */
1077
1078
if(quit_now){
1079
avahi_s_service_resolver_free(r);
1080
return;
1081
}
1082
1083
switch(event){
1084
default:
1085
case AVAHI_RESOLVER_FAILURE:
1086
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1087
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1088
domain,
1089
avahi_strerror(avahi_server_errno
1090
(((mandos_context*)mc)->server)));
1091
break;
1092
1093
case AVAHI_RESOLVER_FOUND:
1094
{
1095
char ip[AVAHI_ADDRESS_STR_MAX];
1096
avahi_address_snprint(ip, sizeof(ip), address);
1097
if(debug){
1098
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1099
PRIdMAX ") on port %" PRIu16 "\n", name,
1100
host_name, ip, (intmax_t)interface, port);
1101
}
1102
int ret = start_mandos_communication(ip, (in_port_t)port,
1103
interface,
1104
avahi_proto_to_af(proto),
1105
mc);
1106
if(ret == 0){
1107
avahi_simple_poll_quit(simple_poll);
1108
} else {
1109
if(not add_server(ip, (in_port_t)port, interface,
1110
avahi_proto_to_af(proto),
1111
&((mandos_context*)mc)->current_server)){
1112
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1113
" list\n", name);
1114
}
1115
}
1116
}
1117
}
1118
avahi_s_service_resolver_free(r);
1119
}
1120
1121
static void browse_callback(AvahiSServiceBrowser *b,
1122
AvahiIfIndex interface,
1123
AvahiProtocol protocol,
1124
AvahiBrowserEvent event,
1125
const char *name,
1126
const char *type,
1127
const char *domain,
1128
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1129
flags,
1130
void *mc){
1131
if(b == NULL){
1132
return;
1133
}
1134
1135
/* Called whenever a new services becomes available on the LAN or
1136
is removed from the LAN */
1137
1138
if(quit_now){
1139
return;
1140
}
1141
1142
switch(event){
1143
default:
1144
case AVAHI_BROWSER_FAILURE:
1145
1146
fprintf_plus(stderr, "(Avahi browser) %s\n",
1147
avahi_strerror(avahi_server_errno
1148
(((mandos_context*)mc)->server)));
1149
avahi_simple_poll_quit(simple_poll);
1150
return;
1151
1152
case AVAHI_BROWSER_NEW:
1153
/* We ignore the returned Avahi resolver object. In the callback
1154
function we free it. If the Avahi server is terminated before
1155
the callback function is called the Avahi server will free the
1156
resolver for us. */
1157
1158
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1159
interface, protocol, name, type,
1160
domain, protocol, 0,
1161
resolve_callback, mc) == NULL)
1162
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1163
" %s\n", name,
1164
avahi_strerror(avahi_server_errno
1165
(((mandos_context*)mc)->server)));
1166
break;
1167
1168
case AVAHI_BROWSER_REMOVE:
1169
break;
1170
1171
case AVAHI_BROWSER_ALL_FOR_NOW:
1172
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1173
if(debug){
1174
fprintf_plus(stderr, "No Mandos server found, still"
1175
" searching...\n");
1176
}
1177
break;
1178
}
1179
}
1180
1181
/* Signal handler that stops main loop after SIGTERM */
1182
static void handle_sigterm(int sig){
1183
if(quit_now){
1184
return;
1185
}
1186
quit_now = 1;
1187
signal_received = sig;
1188
int old_errno = errno;
1189
/* set main loop to exit */
1190
if(simple_poll != NULL){
1191
avahi_simple_poll_quit(simple_poll);
1192
}
1193
errno = old_errno;
1194
}
1195
1196
__attribute__((nonnull, warn_unused_result))
1197
bool get_flags(const char *ifname, struct ifreq *ifr){
1198
int ret;
1199
error_t ret_errno;
1200
1201
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1202
if(s < 0){
1203
ret_errno = errno;
1204
perror_plus("socket");
1205
errno = ret_errno;
1206
return false;
1207
}
1208
strcpy(ifr->ifr_name, ifname);
1209
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1210
if(ret == -1){
1211
if(debug){
1212
ret_errno = errno;
1213
perror_plus("ioctl SIOCGIFFLAGS");
1214
errno = ret_errno;
1215
}
1216
return false;
1217
}
1218
return true;
1219
}
1220
1221
__attribute__((nonnull, warn_unused_result))
1222
bool good_flags(const char *ifname, const struct ifreq *ifr){
1223
1224
/* Reject the loopback device */
1225
if(ifr->ifr_flags & IFF_LOOPBACK){
1226
if(debug){
1227
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1228
ifname);
1229
}
1230
return false;
1231
}
1232
/* Accept point-to-point devices only if connect_to is specified */
1233
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1234
if(debug){
1235
fprintf_plus(stderr, "Accepting point-to-point interface"
1236
" \"%s\"\n", ifname);
1237
}
1238
return true;
1239
}
1240
/* Otherwise, reject non-broadcast-capable devices */
1241
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1242
if(debug){
1243
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1244
" \"%s\"\n", ifname);
1245
}
1246
return false;
1247
}
1248
/* Reject non-ARP interfaces (including dummy interfaces) */
1249
if(ifr->ifr_flags & IFF_NOARP){
1250
if(debug){
1251
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1252
ifname);
1253
}
1254
return false;
1255
}
1256
1257
/* Accept this device */
1258
if(debug){
1259
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1260
}
1261
return true;
1262
}
1263
1264
/*
1265
* This function determines if a directory entry in /sys/class/net
1266
* corresponds to an acceptable network device.
1267
* (This function is passed to scandir(3) as a filter function.)
1268
*/
1269
__attribute__((nonnull, warn_unused_result))
1270
int good_interface(const struct dirent *if_entry){
1271
if(if_entry->d_name[0] == '.'){
1272
return 0;
1273
}
1274
1275
struct ifreq ifr;
1276
if(not get_flags(if_entry->d_name, &ifr)){
1277
if(debug){
1278
fprintf_plus(stderr, "Failed to get flags for interface "
1279
"\"%s\"\n", if_entry->d_name);
1280
}
1281
return 0;
1282
}
1283
1284
if(not good_flags(if_entry->d_name, &ifr)){
1285
return 0;
1286
}
1287
return 1;
1288
}
1289
1290
/*
1291
* This function determines if a network interface is up.
1292
*/
1293
__attribute__((nonnull, warn_unused_result))
1294
bool interface_is_up(const char *interface){
1295
struct ifreq ifr;
1296
if(not get_flags(interface, &ifr)){
1297
if(debug){
1298
fprintf_plus(stderr, "Failed to get flags for interface "
1299
"\"%s\"\n", interface);
1300
}
1301
return false;
1302
}
1303
1304
return (bool)(ifr.ifr_flags & IFF_UP);
1305
}
1306
1307
/*
1308
* This function determines if a network interface is running
1309
*/
1310
__attribute__((nonnull, warn_unused_result))
1311
bool interface_is_running(const char *interface){
1312
struct ifreq ifr;
1313
if(not get_flags(interface, &ifr)){
1314
if(debug){
1315
fprintf_plus(stderr, "Failed to get flags for interface "
1316
"\"%s\"\n", interface);
1317
}
1318
return false;
1319
}
1320
1321
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1322
}
1323
1324
__attribute__((nonnull, pure, warn_unused_result))
1325
int notdotentries(const struct dirent *direntry){
1326
/* Skip "." and ".." */
1327
if(direntry->d_name[0] == '.'
1328
and (direntry->d_name[1] == '\0'
1329
or (direntry->d_name[1] == '.'
1330
and direntry->d_name[2] == '\0'))){
1331
return 0;
1332
}
1333
return 1;
1334
}
1335
1336
/* Is this directory entry a runnable program? */
1337
__attribute__((nonnull, warn_unused_result))
1338
int runnable_hook(const struct dirent *direntry){
1339
int ret;
1340
size_t sret;
1341
struct stat st;
1342
1343
if((direntry->d_name)[0] == '\0'){
1344
/* Empty name? */
1345
return 0;
1346
}
1347
1348
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1349
"abcdefghijklmnopqrstuvwxyz"
1350
"0123456789"
1351
"_.-");
1352
if((direntry->d_name)[sret] != '\0'){
1353
/* Contains non-allowed characters */
1354
if(debug){
1355
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1356
direntry->d_name);
1357
}
1358
return 0;
1359
}
1360
1361
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1362
if(ret == -1){
1363
if(debug){
1364
perror_plus("Could not stat hook");
1365
}
1366
return 0;
1367
}
1368
if(not (S_ISREG(st.st_mode))){
1369
/* Not a regular file */
1370
if(debug){
1371
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1372
direntry->d_name);
1373
}
1374
return 0;
1375
}
1376
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1377
/* Not executable */
1378
if(debug){
1379
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1380
direntry->d_name);
1381
}
1382
return 0;
1383
}
1384
if(debug){
1385
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1386
direntry->d_name);
1387
}
1388
return 1;
1389
}
1390
1391
__attribute__((nonnull, warn_unused_result))
1392
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1393
mandos_context *mc){
1394
int ret;
1395
struct timespec now;
1396
struct timespec waited_time;
1397
intmax_t block_time;
1398
1399
while(true){
1400
if(mc->current_server == NULL){
1401
if(debug){
1402
fprintf_plus(stderr, "Wait until first server is found."
1403
" No timeout!\n");
1404
}
1405
ret = avahi_simple_poll_iterate(s, -1);
1406
} else {
1407
if(debug){
1408
fprintf_plus(stderr, "Check current_server if we should run"
1409
" it, or wait\n");
1410
}
1411
/* the current time */
1412
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1413
if(ret == -1){
1414
perror_plus("clock_gettime");
1415
return -1;
1416
}
1417
/* Calculating in ms how long time between now and server
1418
who we visted longest time ago. Now - last seen. */
1419
waited_time.tv_sec = (now.tv_sec
1420
- mc->current_server->last_seen.tv_sec);
1421
waited_time.tv_nsec = (now.tv_nsec
1422
- mc->current_server->last_seen.tv_nsec);
1423
/* total time is 10s/10,000ms.
1424
Converting to s from ms by dividing by 1,000,
1425
and ns to ms by dividing by 1,000,000. */
1426
block_time = ((retry_interval
1427
- ((intmax_t)waited_time.tv_sec * 1000))
1428
- ((intmax_t)waited_time.tv_nsec / 1000000));
1429
1430
if(debug){
1431
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1432
block_time);
1433
}
1434
1435
if(block_time <= 0){
1436
ret = start_mandos_communication(mc->current_server->ip,
1437
mc->current_server->port,
1438
mc->current_server->if_index,
1439
mc->current_server->af, mc);
1440
if(ret == 0){
1441
avahi_simple_poll_quit(s);
1442
return 0;
1443
}
1444
ret = clock_gettime(CLOCK_MONOTONIC,
1445
&mc->current_server->last_seen);
1446
if(ret == -1){
1447
perror_plus("clock_gettime");
1448
return -1;
1449
}
1450
mc->current_server = mc->current_server->next;
1451
block_time = 0; /* Call avahi to find new Mandos
1452
servers, but don't block */
1453
}
1454
1455
ret = avahi_simple_poll_iterate(s, (int)block_time);
1456
}
1457
if(ret != 0){
1458
if(ret > 0 or errno != EINTR){
1459
return (ret != 1) ? ret : 0;
1460
}
1461
}
1462
}
1463
}
1464
1465
/* Set effective uid to 0, return errno */
1466
__attribute__((warn_unused_result))
1467
error_t raise_privileges(void){
1468
error_t old_errno = errno;
1469
error_t ret_errno = 0;
1470
if(seteuid(0) == -1){
1471
ret_errno = errno;
1472
}
1473
errno = old_errno;
1474
return ret_errno;
1475
}
1476
1477
/* Set effective and real user ID to 0. Return errno. */
1478
__attribute__((warn_unused_result))
1479
error_t raise_privileges_permanently(void){
1480
error_t old_errno = errno;
1481
error_t ret_errno = raise_privileges();
1482
if(ret_errno != 0){
1483
errno = old_errno;
1484
return ret_errno;
1485
}
1486
if(setuid(0) == -1){
1487
ret_errno = errno;
1488
}
1489
errno = old_errno;
1490
return ret_errno;
1491
}
1492
1493
/* Set effective user ID to unprivileged saved user ID */
1494
__attribute__((warn_unused_result))
1495
error_t lower_privileges(void){
1496
error_t old_errno = errno;
1497
error_t ret_errno = 0;
1498
if(seteuid(uid) == -1){
1499
ret_errno = errno;
1500
}
1501
errno = old_errno;
1502
return ret_errno;
1503
}
1504
1505
/* Lower privileges permanently */
1506
__attribute__((warn_unused_result))
1507
error_t lower_privileges_permanently(void){
1508
error_t old_errno = errno;
1509
error_t ret_errno = 0;
1510
if(setuid(uid) == -1){
1511
ret_errno = errno;
1512
}
1513
errno = old_errno;
1514
return ret_errno;
1515
}
1516
1517
__attribute__((nonnull))
1518
void run_network_hooks(const char *mode, const char *interface,
1519
const float delay){
1520
struct dirent **direntries = NULL;
1521
if(hookdir_fd == -1){
1522
hookdir_fd = open(hookdir, O_RDONLY);
1523
if(hookdir_fd == -1){
1524
if(errno == ENOENT){
1525
if(debug){
1526
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1527
" found\n", hookdir);
1528
}
1529
} else {
1530
perror_plus("open");
1531
}
1532
return;
1533
}
1534
}
1535
#ifdef __GLIBC__
1536
#if __GLIBC_PREREQ(2, 15)
1537
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1538
runnable_hook, alphasort);
1539
#else /* not __GLIBC_PREREQ(2, 15) */
1540
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1541
alphasort);
1542
#endif /* not __GLIBC_PREREQ(2, 15) */
1543
#else /* not __GLIBC__ */
1544
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1545
alphasort);
1546
#endif /* not __GLIBC__ */
1547
if(numhooks == -1){
1548
perror_plus("scandir");
1549
return;
1550
}
1551
struct dirent *direntry;
1552
int ret;
1553
int devnull = open("/dev/null", O_RDONLY);
1554
for(int i = 0; i < numhooks; i++){
1555
direntry = direntries[i];
1556
if(debug){
1557
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1558
direntry->d_name);
1559
}
1560
pid_t hook_pid = fork();
1561
if(hook_pid == 0){
1562
/* Child */
1563
/* Raise privileges */
1564
errno = raise_privileges_permanently();
1565
if(errno != 0){
1566
perror_plus("Failed to raise privileges");
1567
_exit(EX_NOPERM);
1568
}
1569
/* Set group */
1570
errno = 0;
1571
ret = setgid(0);
1572
if(ret == -1){
1573
perror_plus("setgid");
1574
_exit(EX_NOPERM);
1575
}
1576
/* Reset supplementary groups */
1577
errno = 0;
1578
ret = setgroups(0, NULL);
1579
if(ret == -1){
1580
perror_plus("setgroups");
1581
_exit(EX_NOPERM);
1582
}
1583
ret = dup2(devnull, STDIN_FILENO);
1584
if(ret == -1){
1585
perror_plus("dup2(devnull, STDIN_FILENO)");
1586
_exit(EX_OSERR);
1587
}
1588
ret = close(devnull);
1589
if(ret == -1){
1590
perror_plus("close");
1591
_exit(EX_OSERR);
1592
}
1593
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1594
if(ret == -1){
1595
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1596
_exit(EX_OSERR);
1597
}
1598
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1599
if(ret == -1){
1600
perror_plus("setenv");
1601
_exit(EX_OSERR);
1602
}
1603
ret = setenv("DEVICE", interface, 1);
1604
if(ret == -1){
1605
perror_plus("setenv");
1606
_exit(EX_OSERR);
1607
}
1608
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1609
if(ret == -1){
1610
perror_plus("setenv");
1611
_exit(EX_OSERR);
1612
}
1613
ret = setenv("MODE", mode, 1);
1614
if(ret == -1){
1615
perror_plus("setenv");
1616
_exit(EX_OSERR);
1617
}
1618
char *delaystring;
1619
ret = asprintf(&delaystring, "%f", (double)delay);
1620
if(ret == -1){
1621
perror_plus("asprintf");
1622
_exit(EX_OSERR);
1623
}
1624
ret = setenv("DELAY", delaystring, 1);
1625
if(ret == -1){
1626
free(delaystring);
1627
perror_plus("setenv");
1628
_exit(EX_OSERR);
1629
}
1630
free(delaystring);
1631
if(connect_to != NULL){
1632
ret = setenv("CONNECT", connect_to, 1);
1633
if(ret == -1){
1634
perror_plus("setenv");
1635
_exit(EX_OSERR);
1636
}
1637
}
1638
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1639
if(hook_fd == -1){
1640
perror_plus("openat");
1641
_exit(EXIT_FAILURE);
1642
}
1643
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1644
perror_plus("close");
1645
_exit(EXIT_FAILURE);
1646
}
1647
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1648
environ) == -1){
1649
perror_plus("fexecve");
1650
_exit(EXIT_FAILURE);
1651
}
1652
} else {
1653
if(hook_pid == -1){
1654
perror_plus("fork");
1655
free(direntry);
1656
continue;
1657
}
1658
int status;
1659
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1660
perror_plus("waitpid");
1661
free(direntry);
1662
continue;
1663
}
1664
if(WIFEXITED(status)){
1665
if(WEXITSTATUS(status) != 0){
1666
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1667
" with status %d\n", direntry->d_name,
1668
WEXITSTATUS(status));
1669
free(direntry);
1670
continue;
1671
}
1672
} else if(WIFSIGNALED(status)){
1673
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1674
" signal %d\n", direntry->d_name,
1675
WTERMSIG(status));
1676
free(direntry);
1677
continue;
1678
} else {
1679
fprintf_plus(stderr, "Warning: network hook \"%s\""
1680
" crashed\n", direntry->d_name);
1681
free(direntry);
1682
continue;
1683
}
1684
}
1685
if(debug){
1686
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1687
direntry->d_name);
1688
}
1689
free(direntry);
1690
}
1691
free(direntries);
1692
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1693
perror_plus("close");
1694
} else {
1695
hookdir_fd = -1;
1696
}
1697
close(devnull);
1698
}
1699
1700
__attribute__((nonnull, warn_unused_result))
1701
error_t bring_up_interface(const char *const interface,
1702
const float delay){
1703
error_t old_errno = errno;
1704
int ret;
1705
struct ifreq network;
1706
unsigned int if_index = if_nametoindex(interface);
1707
if(if_index == 0){
1708
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1709
errno = old_errno;
1710
return ENXIO;
1711
}
1712
1713
if(quit_now){
1714
errno = old_errno;
1715
return EINTR;
1716
}
1717
1718
if(not interface_is_up(interface)){
1719
error_t ret_errno = 0, ioctl_errno = 0;
1720
if(not get_flags(interface, &network)){
1721
ret_errno = errno;
1722
fprintf_plus(stderr, "Failed to get flags for interface "
1723
"\"%s\"\n", interface);
1724
errno = old_errno;
1725
return ret_errno;
1726
}
1727
network.ifr_flags |= IFF_UP; /* set flag */
1728
1729
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1730
if(sd == -1){
1731
ret_errno = errno;
1732
perror_plus("socket");
1733
errno = old_errno;
1734
return ret_errno;
1735
}
1736
1737
if(quit_now){
1738
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1739
if(ret == -1){
1740
perror_plus("close");
1741
}
1742
errno = old_errno;
1743
return EINTR;
1744
}
1745
1746
if(debug){
1747
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1748
interface);
1749
}
1750
1751
/* Raise privileges */
1752
ret_errno = raise_privileges();
1753
if(ret_errno != 0){
1754
errno = ret_errno;
1755
perror_plus("Failed to raise privileges");
1756
}
1757
1758
#ifdef __linux__
1759
int ret_linux;
1760
bool restore_loglevel = false;
1761
if(ret_errno == 0){
1762
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1763
messages about the network interface to mess up the prompt */
1764
ret_linux = klogctl(8, NULL, 5);
1765
if(ret_linux == -1){
1766
perror_plus("klogctl");
1767
} else {
1768
restore_loglevel = true;
1769
}
1770
}
1771
#endif /* __linux__ */
1772
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1773
ioctl_errno = errno;
1774
#ifdef __linux__
1775
if(restore_loglevel){
1776
ret_linux = klogctl(7, NULL, 0);
1777
if(ret_linux == -1){
1778
perror_plus("klogctl");
1779
}
1780
}
1781
#endif /* __linux__ */
1782
1783
/* If raise_privileges() succeeded above */
1784
if(ret_errno == 0){
1785
/* Lower privileges */
1786
ret_errno = lower_privileges();
1787
if(ret_errno != 0){
1788
errno = ret_errno;
1789
perror_plus("Failed to lower privileges");
1790
}
1791
}
1792
1793
/* Close the socket */
1794
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1795
if(ret == -1){
1796
perror_plus("close");
1797
}
1798
1799
if(ret_setflags == -1){
1800
errno = ioctl_errno;
1801
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1802
errno = old_errno;
1803
return ioctl_errno;
1804
}
1805
} else if(debug){
1806
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1807
interface);
1808
}
1809
1810
/* Sleep checking until interface is running.
1811
Check every 0.25s, up to total time of delay */
1812
for(int i=0; i < delay * 4; i++){
1813
if(interface_is_running(interface)){
1814
break;
1815
}
1816
struct timespec sleeptime = { .tv_nsec = 250000000 };
1817
ret = nanosleep(&sleeptime, NULL);
1818
if(ret == -1 and errno != EINTR){
1819
perror_plus("nanosleep");
1820
}
1821
}
1822
1823
errno = old_errno;
1824
return 0;
1825
}
1826
1827
__attribute__((nonnull, warn_unused_result))
1828
error_t take_down_interface(const char *const interface){
1829
error_t old_errno = errno;
1830
struct ifreq network;
1831
unsigned int if_index = if_nametoindex(interface);
1832
if(if_index == 0){
1833
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1834
errno = old_errno;
1835
return ENXIO;
1836
}
1837
if(interface_is_up(interface)){
1838
error_t ret_errno = 0, ioctl_errno = 0;
1839
if(not get_flags(interface, &network) and debug){
1840
ret_errno = errno;
1841
fprintf_plus(stderr, "Failed to get flags for interface "
1842
"\"%s\"\n", interface);
1843
errno = old_errno;
1844
return ret_errno;
1845
}
1846
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1847
1848
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1849
if(sd == -1){
1850
ret_errno = errno;
1851
perror_plus("socket");
1852
errno = old_errno;
1853
return ret_errno;
1854
}
1855
1856
if(debug){
1857
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1858
interface);
1859
}
1860
1861
/* Raise privileges */
1862
ret_errno = raise_privileges();
1863
if(ret_errno != 0){
1864
errno = ret_errno;
1865
perror_plus("Failed to raise privileges");
1866
}
1867
1868
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1869
ioctl_errno = errno;
1870
1871
/* If raise_privileges() succeeded above */
1872
if(ret_errno == 0){
1873
/* Lower privileges */
1874
ret_errno = lower_privileges();
1875
if(ret_errno != 0){
1876
errno = ret_errno;
1877
perror_plus("Failed to lower privileges");
1878
}
1879
}
1880
1881
/* Close the socket */
1882
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1883
if(ret == -1){
1884
perror_plus("close");
1885
}
1886
1887
if(ret_setflags == -1){
1888
errno = ioctl_errno;
1889
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1890
errno = old_errno;
1891
return ioctl_errno;
1892
}
1893
} else if(debug){
1894
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1895
interface);
1896
}
1897
1898
errno = old_errno;
1899
return 0;
1900
}
1901
1902
int main(int argc, char *argv[]){
1903
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1904
.priority = "SECURE256:!CTYPE-X.509:"
1905
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
1906
.interfaces = NULL, .interfaces_size = 0 };
1907
AvahiSServiceBrowser *sb = NULL;
1908
error_t ret_errno;
1909
int ret;
1910
intmax_t tmpmax;
1911
char *tmp;
1912
int exitcode = EXIT_SUCCESS;
1913
char *interfaces_to_take_down = NULL;
1914
size_t interfaces_to_take_down_size = 0;
1915
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1916
char old_tempdir[] = "/tmp/mandosXXXXXX";
1917
char *tempdir = NULL;
1918
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1919
const char *seckey = PATHDIR "/" SECKEY;
1920
const char *pubkey = PATHDIR "/" PUBKEY;
1921
char *interfaces_hooks = NULL;
1922
1923
bool gnutls_initialized = false;
1924
bool gpgme_initialized = false;
1925
float delay = 2.5f;
1926
double retry_interval = 10; /* 10s between trying a server and
1927
retrying the same server again */
1928
1929
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1930
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1931
1932
uid = getuid();
1933
gid = getgid();
1934
1935
/* Lower any group privileges we might have, just to be safe */
1936
errno = 0;
1937
ret = setgid(gid);
1938
if(ret == -1){
1939
perror_plus("setgid");
1940
}
1941
1942
/* Lower user privileges (temporarily) */
1943
errno = 0;
1944
ret = seteuid(uid);
1945
if(ret == -1){
1946
perror_plus("seteuid");
1947
}
1948
1949
if(quit_now){
1950
goto end;
1951
}
1952
1953
{
1954
struct argp_option options[] = {
1955
{ .name = "debug", .key = 128,
1956
.doc = "Debug mode", .group = 3 },
1957
{ .name = "connect", .key = 'c',
1958
.arg = "ADDRESS:PORT",
1959
.doc = "Connect directly to a specific Mandos server",
1960
.group = 1 },
1961
{ .name = "interface", .key = 'i',
1962
.arg = "NAME",
1963
.doc = "Network interface that will be used to search for"
1964
" Mandos servers",
1965
.group = 1 },
1966
{ .name = "seckey", .key = 's',
1967
.arg = "FILE",
1968
.doc = "OpenPGP secret key file base name",
1969
.group = 1 },
1970
{ .name = "pubkey", .key = 'p',
1971
.arg = "FILE",
1972
.doc = "OpenPGP public key file base name",
1973
.group = 2 },
1974
{ .name = "dh-bits", .key = 129,
1975
.arg = "BITS",
1976
.doc = "Bit length of the prime number used in the"
1977
" Diffie-Hellman key exchange",
1978
.group = 2 },
1979
{ .name = "priority", .key = 130,
1980
.arg = "STRING",
1981
.doc = "GnuTLS priority string for the TLS handshake",
1982
.group = 1 },
1983
{ .name = "delay", .key = 131,
1984
.arg = "SECONDS",
1985
.doc = "Maximum delay to wait for interface startup",
1986
.group = 2 },
1987
{ .name = "retry", .key = 132,
1988
.arg = "SECONDS",
1989
.doc = "Retry interval used when denied by the Mandos server",
1990
.group = 2 },
1991
{ .name = "network-hook-dir", .key = 133,
1992
.arg = "DIR",
1993
.doc = "Directory where network hooks are located",
1994
.group = 2 },
1995
/*
1996
* These reproduce what we would get without ARGP_NO_HELP
1997
*/
1998
{ .name = "help", .key = '?',
1999
.doc = "Give this help list", .group = -1 },
2000
{ .name = "usage", .key = -3,
2001
.doc = "Give a short usage message", .group = -1 },
2002
{ .name = "version", .key = 'V',
2003
.doc = "Print program version", .group = -1 },
2004
{ .name = NULL }
2005
};
2006
2007
error_t parse_opt(int key, char *arg,
2008
struct argp_state *state){
2009
errno = 0;
2010
switch(key){
2011
case 128: /* --debug */
2012
debug = true;
2013
break;
2014
case 'c': /* --connect */
2015
connect_to = arg;
2016
break;
2017
case 'i': /* --interface */
2018
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2019
arg, (int)',');
2020
if(ret_errno != 0){
2021
argp_error(state, "%s", strerror(ret_errno));
2022
}
2023
break;
2024
case 's': /* --seckey */
2025
seckey = arg;
2026
break;
2027
case 'p': /* --pubkey */
2028
pubkey = arg;
2029
break;
2030
case 129: /* --dh-bits */
2031
errno = 0;
2032
tmpmax = strtoimax(arg, &tmp, 10);
2033
if(errno != 0 or tmp == arg or *tmp != '\0'
2034
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2035
argp_error(state, "Bad number of DH bits");
2036
}
2037
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2038
break;
2039
case 130: /* --priority */
2040
mc.priority = arg;
2041
break;
2042
case 131: /* --delay */
2043
errno = 0;
2044
delay = strtof(arg, &tmp);
2045
if(errno != 0 or tmp == arg or *tmp != '\0'){
2046
argp_error(state, "Bad delay");
2047
}
2048
case 132: /* --retry */
2049
errno = 0;
2050
retry_interval = strtod(arg, &tmp);
2051
if(errno != 0 or tmp == arg or *tmp != '\0'
2052
or (retry_interval * 1000) > INT_MAX
2053
or retry_interval < 0){
2054
argp_error(state, "Bad retry interval");
2055
}
2056
break;
2057
case 133: /* --network-hook-dir */
2058
hookdir = arg;
2059
break;
2060
/*
2061
* These reproduce what we would get without ARGP_NO_HELP
2062
*/
2063
case '?': /* --help */
2064
argp_state_help(state, state->out_stream,
2065
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2066
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2067
case -3: /* --usage */
2068
argp_state_help(state, state->out_stream,
2069
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2070
case 'V': /* --version */
2071
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2072
exit(argp_err_exit_status);
2073
break;
2074
default:
2075
return ARGP_ERR_UNKNOWN;
2076
}
2077
return errno;
2078
}
2079
2080
struct argp argp = { .options = options, .parser = parse_opt,
2081
.args_doc = "",
2082
.doc = "Mandos client -- Get and decrypt"
2083
" passwords from a Mandos server" };
2084
ret = argp_parse(&argp, argc, argv,
2085
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2086
switch(ret){
2087
case 0:
2088
break;
2089
case ENOMEM:
2090
default:
2091
errno = ret;
2092
perror_plus("argp_parse");
2093
exitcode = EX_OSERR;
2094
goto end;
2095
case EINVAL:
2096
exitcode = EX_USAGE;
2097
goto end;
2098
}
2099
}
2100
2101
{
2102
/* Work around Debian bug #633582:
2103
<http://bugs.debian.org/633582> */
2104
2105
/* Re-raise privileges */
2106
ret_errno = raise_privileges();
2107
if(ret_errno != 0){
2108
errno = ret_errno;
2109
perror_plus("Failed to raise privileges");
2110
} else {
2111
struct stat st;
2112
2113
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2114
int seckey_fd = open(seckey, O_RDONLY);
2115
if(seckey_fd == -1){
2116
perror_plus("open");
2117
} else {
2118
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2119
if(ret == -1){
2120
perror_plus("fstat");
2121
} else {
2122
if(S_ISREG(st.st_mode)
2123
and st.st_uid == 0 and st.st_gid == 0){
2124
ret = fchown(seckey_fd, uid, gid);
2125
if(ret == -1){
2126
perror_plus("fchown");
2127
}
2128
}
2129
}
2130
TEMP_FAILURE_RETRY(close(seckey_fd));
2131
}
2132
}
2133
2134
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2135
int pubkey_fd = open(pubkey, O_RDONLY);
2136
if(pubkey_fd == -1){
2137
perror_plus("open");
2138
} else {
2139
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2140
if(ret == -1){
2141
perror_plus("fstat");
2142
} else {
2143
if(S_ISREG(st.st_mode)
2144
and st.st_uid == 0 and st.st_gid == 0){
2145
ret = fchown(pubkey_fd, uid, gid);
2146
if(ret == -1){
2147
perror_plus("fchown");
2148
}
2149
}
2150
}
2151
TEMP_FAILURE_RETRY(close(pubkey_fd));
2152
}
2153
}
2154
2155
/* Lower privileges */
2156
ret_errno = lower_privileges();
2157
if(ret_errno != 0){
2158
errno = ret_errno;
2159
perror_plus("Failed to lower privileges");
2160
}
2161
}
2162
}
2163
2164
/* Remove invalid interface names (except "none") */
2165
{
2166
char *interface = NULL;
2167
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2168
interface))){
2169
if(strcmp(interface, "none") != 0
2170
and if_nametoindex(interface) == 0){
2171
if(interface[0] != '\0'){
2172
fprintf_plus(stderr, "Not using nonexisting interface"
2173
" \"%s\"\n", interface);
2174
}
2175
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2176
interface = NULL;
2177
}
2178
}
2179
}
2180
2181
/* Run network hooks */
2182
{
2183
if(mc.interfaces != NULL){
2184
interfaces_hooks = malloc(mc.interfaces_size);
2185
if(interfaces_hooks == NULL){
2186
perror_plus("malloc");
2187
goto end;
2188
}
2189
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2190
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2191
}
2192
run_network_hooks("start", interfaces_hooks != NULL ?
2193
interfaces_hooks : "", delay);
2194
}
2195
2196
if(not debug){
2197
avahi_set_log_function(empty_log);
2198
}
2199
2200
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2201
from the signal handler */
2202
/* Initialize the pseudo-RNG for Avahi */
2203
srand((unsigned int) time(NULL));
2204
simple_poll = avahi_simple_poll_new();
2205
if(simple_poll == NULL){
2206
fprintf_plus(stderr,
2207
"Avahi: Failed to create simple poll object.\n");
2208
exitcode = EX_UNAVAILABLE;
2209
goto end;
2210
}
2211
2212
sigemptyset(&sigterm_action.sa_mask);
2213
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2214
if(ret == -1){
2215
perror_plus("sigaddset");
2216
exitcode = EX_OSERR;
2217
goto end;
2218
}
2219
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2220
if(ret == -1){
2221
perror_plus("sigaddset");
2222
exitcode = EX_OSERR;
2223
goto end;
2224
}
2225
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2226
if(ret == -1){
2227
perror_plus("sigaddset");
2228
exitcode = EX_OSERR;
2229
goto end;
2230
}
2231
/* Need to check if the handler is SIG_IGN before handling:
2232
| [[info:libc:Initial Signal Actions]] |
2233
| [[info:libc:Basic Signal Handling]] |
2234
*/
2235
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2236
if(ret == -1){
2237
perror_plus("sigaction");
2238
return EX_OSERR;
2239
}
2240
if(old_sigterm_action.sa_handler != SIG_IGN){
2241
ret = sigaction(SIGINT, &sigterm_action, NULL);
2242
if(ret == -1){
2243
perror_plus("sigaction");
2244
exitcode = EX_OSERR;
2245
goto end;
2246
}
2247
}
2248
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2249
if(ret == -1){
2250
perror_plus("sigaction");
2251
return EX_OSERR;
2252
}
2253
if(old_sigterm_action.sa_handler != SIG_IGN){
2254
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2255
if(ret == -1){
2256
perror_plus("sigaction");
2257
exitcode = EX_OSERR;
2258
goto end;
2259
}
2260
}
2261
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2262
if(ret == -1){
2263
perror_plus("sigaction");
2264
return EX_OSERR;
2265
}
2266
if(old_sigterm_action.sa_handler != SIG_IGN){
2267
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2268
if(ret == -1){
2269
perror_plus("sigaction");
2270
exitcode = EX_OSERR;
2271
goto end;
2272
}
2273
}
2274
2275
/* If no interfaces were specified, make a list */
2276
if(mc.interfaces == NULL){
2277
struct dirent **direntries = NULL;
2278
/* Look for any good interfaces */
2279
ret = scandir(sys_class_net, &direntries, good_interface,
2280
alphasort);
2281
if(ret >= 1){
2282
/* Add all found interfaces to interfaces list */
2283
for(int i = 0; i < ret; ++i){
2284
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2285
direntries[i]->d_name);
2286
if(ret_errno != 0){
2287
errno = ret_errno;
2288
perror_plus("argz_add");
2289
free(direntries[i]);
2290
continue;
2291
}
2292
if(debug){
2293
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2294
direntries[i]->d_name);
2295
}
2296
free(direntries[i]);
2297
}
2298
free(direntries);
2299
} else {
2300
if(ret == 0){
2301
free(direntries);
2302
}
2303
fprintf_plus(stderr, "Could not find a network interface\n");
2304
exitcode = EXIT_FAILURE;
2305
goto end;
2306
}
2307
}
2308
2309
/* Bring up interfaces which are down, and remove any "none"s */
2310
{
2311
char *interface = NULL;
2312
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2313
interface))){
2314
/* If interface name is "none", stop bringing up interfaces.
2315
Also remove all instances of "none" from the list */
2316
if(strcmp(interface, "none") == 0){
2317
argz_delete(&mc.interfaces, &mc.interfaces_size,
2318
interface);
2319
interface = NULL;
2320
while((interface = argz_next(mc.interfaces,
2321
mc.interfaces_size, interface))){
2322
if(strcmp(interface, "none") == 0){
2323
argz_delete(&mc.interfaces, &mc.interfaces_size,
2324
interface);
2325
interface = NULL;
2326
}
2327
}
2328
break;
2329
}
2330
bool interface_was_up = interface_is_up(interface);
2331
errno = bring_up_interface(interface, delay);
2332
if(not interface_was_up){
2333
if(errno != 0){
2334
perror_plus("Failed to bring up interface");
2335
} else {
2336
errno = argz_add(&interfaces_to_take_down,
2337
&interfaces_to_take_down_size,
2338
interface);
2339
if(errno != 0){
2340
perror_plus("argz_add");
2341
}
2342
}
2343
}
2344
}
2345
if(debug and (interfaces_to_take_down == NULL)){
2346
fprintf_plus(stderr, "No interfaces were brought up\n");
2347
}
2348
}
2349
2350
/* If we only got one interface, explicitly use only that one */
2351
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2352
if(debug){
2353
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2354
mc.interfaces);
2355
}
2356
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2357
}
2358
2359
if(quit_now){
2360
goto end;
2361
}
2362
2363
ret = init_gnutls_global(pubkey, seckey, &mc);
2364
if(ret == -1){
2365
fprintf_plus(stderr, "init_gnutls_global failed\n");
2366
exitcode = EX_UNAVAILABLE;
2367
goto end;
2368
} else {
2369
gnutls_initialized = true;
2370
}
2371
2372
if(quit_now){
2373
goto end;
2374
}
2375
2376
/* Try /run/tmp before /tmp */
2377
tempdir = mkdtemp(run_tempdir);
2378
if(tempdir == NULL and errno == ENOENT){
2379
if(debug){
2380
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2381
run_tempdir, old_tempdir);
2382
}
2383
tempdir = mkdtemp(old_tempdir);
2384
}
2385
if(tempdir == NULL){
2386
perror_plus("mkdtemp");
2387
goto end;
2388
}
2389
2390
if(quit_now){
2391
goto end;
2392
}
2393
2394
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2395
fprintf_plus(stderr, "init_gpgme failed\n");
2396
exitcode = EX_UNAVAILABLE;
2397
goto end;
2398
} else {
2399
gpgme_initialized = true;
2400
}
2401
2402
if(quit_now){
2403
goto end;
2404
}
2405
2406
if(connect_to != NULL){
2407
/* Connect directly, do not use Zeroconf */
2408
/* (Mainly meant for debugging) */
2409
char *address = strrchr(connect_to, ':');
2410
2411
if(address == NULL){
2412
fprintf_plus(stderr, "No colon in address\n");
2413
exitcode = EX_USAGE;
2414
goto end;
2415
}
2416
2417
if(quit_now){
2418
goto end;
2419
}
2420
2421
in_port_t port;
2422
errno = 0;
2423
tmpmax = strtoimax(address+1, &tmp, 10);
2424
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2425
or tmpmax != (in_port_t)tmpmax){
2426
fprintf_plus(stderr, "Bad port number\n");
2427
exitcode = EX_USAGE;
2428
goto end;
2429
}
2430
2431
if(quit_now){
2432
goto end;
2433
}
2434
2435
port = (in_port_t)tmpmax;
2436
*address = '\0';
2437
/* Colon in address indicates IPv6 */
2438
int af;
2439
if(strchr(connect_to, ':') != NULL){
2440
af = AF_INET6;
2441
/* Accept [] around IPv6 address - see RFC 5952 */
2442
if(connect_to[0] == '[' and address[-1] == ']')
2443
{
2444
connect_to++;
2445
address[-1] = '\0';
2446
}
2447
} else {
2448
af = AF_INET;
2449
}
2450
address = connect_to;
2451
2452
if(quit_now){
2453
goto end;
2454
}
2455
2456
while(not quit_now){
2457
ret = start_mandos_communication(address, port, if_index, af,
2458
&mc);
2459
if(quit_now or ret == 0){
2460
break;
2461
}
2462
if(debug){
2463
fprintf_plus(stderr, "Retrying in %d seconds\n",
2464
(int)retry_interval);
2465
}
2466
sleep((unsigned int)retry_interval);
2467
}
2468
2469
if(not quit_now){
2470
exitcode = EXIT_SUCCESS;
2471
}
2472
2473
goto end;
2474
}
2475
2476
if(quit_now){
2477
goto end;
2478
}
2479
2480
{
2481
AvahiServerConfig config;
2482
/* Do not publish any local Zeroconf records */
2483
avahi_server_config_init(&config);
2484
config.publish_hinfo = 0;
2485
config.publish_addresses = 0;
2486
config.publish_workstation = 0;
2487
config.publish_domain = 0;
2488
2489
/* Allocate a new server */
2490
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2491
&config, NULL, NULL, &ret_errno);
2492
2493
/* Free the Avahi configuration data */
2494
avahi_server_config_free(&config);
2495
}
2496
2497
/* Check if creating the Avahi server object succeeded */
2498
if(mc.server == NULL){
2499
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2500
avahi_strerror(ret_errno));
2501
exitcode = EX_UNAVAILABLE;
2502
goto end;
2503
}
2504
2505
if(quit_now){
2506
goto end;
2507
}
2508
2509
/* Create the Avahi service browser */
2510
sb = avahi_s_service_browser_new(mc.server, if_index,
2511
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2512
NULL, 0, browse_callback,
2513
(void *)&mc);
2514
if(sb == NULL){
2515
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2516
avahi_strerror(avahi_server_errno(mc.server)));
2517
exitcode = EX_UNAVAILABLE;
2518
goto end;
2519
}
2520
2521
if(quit_now){
2522
goto end;
2523
}
2524
2525
/* Run the main loop */
2526
2527
if(debug){
2528
fprintf_plus(stderr, "Starting Avahi loop search\n");
2529
}
2530
2531
ret = avahi_loop_with_timeout(simple_poll,
2532
(int)(retry_interval * 1000), &mc);
2533
if(debug){
2534
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2535
(ret == 0) ? "successfully" : "with error");
2536
}
2537
2538
end:
2539
2540
if(debug){
2541
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2542
}
2543
2544
/* Cleanup things */
2545
free(mc.interfaces);
2546
2547
if(sb != NULL)
2548
avahi_s_service_browser_free(sb);
2549
2550
if(mc.server != NULL)
2551
avahi_server_free(mc.server);
2552
2553
if(simple_poll != NULL)
2554
avahi_simple_poll_free(simple_poll);
2555
2556
if(gnutls_initialized){
2557
gnutls_certificate_free_credentials(mc.cred);
2558
gnutls_global_deinit();
2559
gnutls_dh_params_deinit(mc.dh_params);
2560
}
2561
2562
if(gpgme_initialized){
2563
gpgme_release(mc.ctx);
2564
}
2565
2566
/* Cleans up the circular linked list of Mandos servers the client
2567
has seen */
2568
if(mc.current_server != NULL){
2569
mc.current_server->prev->next = NULL;
2570
while(mc.current_server != NULL){
2571
server *next = mc.current_server->next;
2572
#ifdef __GNUC__
2573
#pragma GCC diagnostic push
2574
#pragma GCC diagnostic ignored "-Wcast-qual"
2575
#endif
2576
free((char *)(mc.current_server->ip));
2577
#ifdef __GNUC__
2578
#pragma GCC diagnostic pop
2579
#endif
2580
free(mc.current_server);
2581
mc.current_server = next;
2582
}
2583
}
2584
2585
/* Re-raise privileges */
2586
{
2587
ret_errno = raise_privileges();
2588
if(ret_errno != 0){
2589
errno = ret_errno;
2590
perror_plus("Failed to raise privileges");
2591
} else {
2592
2593
/* Run network hooks */
2594
run_network_hooks("stop", interfaces_hooks != NULL ?
2595
interfaces_hooks : "", delay);
2596
2597
/* Take down the network interfaces which were brought up */
2598
{
2599
char *interface = NULL;
2600
while((interface=argz_next(interfaces_to_take_down,
2601
interfaces_to_take_down_size,
2602
interface))){
2603
ret_errno = take_down_interface(interface);
2604
if(ret_errno != 0){
2605
errno = ret_errno;
2606
perror_plus("Failed to take down interface");
2607
}
2608
}
2609
if(debug and (interfaces_to_take_down == NULL)){
2610
fprintf_plus(stderr, "No interfaces needed to be taken"
2611
" down\n");
2612
}
2613
}
2614
}
2615
2616
ret_errno = lower_privileges_permanently();
2617
if(ret_errno != 0){
2618
errno = ret_errno;
2619
perror_plus("Failed to lower privileges permanently");
2620
}
2621
}
2622
2623
free(interfaces_to_take_down);
2624
free(interfaces_hooks);
2625
2626
/* Removes the GPGME temp directory and all files inside */
2627
if(tempdir != NULL){
2628
struct dirent **direntries = NULL;
2629
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2630
O_NOFOLLOW));
2631
if(tempdir_fd == -1){
2632
perror_plus("open");
2633
} else {
2634
#ifdef __GLIBC__
2635
#if __GLIBC_PREREQ(2, 15)
2636
int numentries = scandirat(tempdir_fd, ".", &direntries,
2637
notdotentries, alphasort);
2638
#else /* not __GLIBC_PREREQ(2, 15) */
2639
int numentries = scandir(tempdir, &direntries, notdotentries,
2640
alphasort);
2641
#endif /* not __GLIBC_PREREQ(2, 15) */
2642
#else /* not __GLIBC__ */
2643
int numentries = scandir(tempdir, &direntries, notdotentries,
2644
alphasort);
2645
#endif /* not __GLIBC__ */
2646
if(numentries >= 0){
2647
for(int i = 0; i < numentries; i++){
2648
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2649
if(ret == -1){
2650
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2651
" \"%s\", 0): %s\n", tempdir,
2652
direntries[i]->d_name, strerror(errno));
2653
}
2654
free(direntries[i]);
2655
}
2656
2657
/* need to clean even if 0 because man page doesn't specify */
2658
free(direntries);
2659
if(numentries == -1){
2660
perror_plus("scandir");
2661
}
2662
ret = rmdir(tempdir);
2663
if(ret == -1 and errno != ENOENT){
2664
perror_plus("rmdir");
2665
}
2666
}
2667
TEMP_FAILURE_RETRY(close(tempdir_fd));
2668
}
2669
}
2670
2671
if(quit_now){
2672
sigemptyset(&old_sigterm_action.sa_mask);
2673
old_sigterm_action.sa_handler = SIG_DFL;
2674
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2675
&old_sigterm_action,
2676
NULL));
2677
if(ret == -1){
2678
perror_plus("sigaction");
2679
}
2680
do {
2681
ret = raise(signal_received);
2682
} while(ret != 0 and errno == EINTR);
2683
if(ret != 0){
2684
perror_plus("raise");
2685
abort();
2686
}
2687
TEMP_FAILURE_RETRY(pause());
2688
}
2689
2690
return exitcode;
2691
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0