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- Committer: Björn Påhlsson
- Date: 2007-10-20 21:38:25 UTC
- Revision ID: belorn@tower-20071020213825-abf6f0d1c33ee961
First working version with: IPv6, GnuTLS, X.509 certificates, DN
retrieval.
retrieval.
- files added:
- bad-ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- network-hooks.d
- plugins.d
- files modified:
- Makefile
added
removed
plugins.d/mandos-client.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos-client - get and decrypt data from a Mandos server
4
*
5
* This program is partly derived from an example program for an Avahi
6
* service browser, downloaded from
7
* <http://avahi.org/browser/examples/core-browse-services.c>. This
8
* includes the following functions: "resolve_callback",
9
* "browse_callback", and parts of "main".
10
*
11
* Everything else is
12
* Copyright © 2008-2013 Teddy Hogeborn
13
* Copyright © 2008-2013 Björn Påhlsson
14
*
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
19
*
20
* This program is distributed in the hope that it will be useful, but
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
* General Public License for more details.
24
*
25
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
*
29
* Contact the authors at <mandos@recompile.se>.
30
*/
31
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
35
#endif
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
38
#endif
39
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
strtof(), abort() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
*/
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
strtoimax() */
64
#include <errno.h> /* perror(), errno,
65
program_invocation_short_name */
66
#include <time.h> /* nanosleep(), time(), sleep() */
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
SIOCSIFFLAGS, if_indextoname(),
69
if_nametoindex(), IF_NAMESIZE */
70
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
72
*/
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), seteuid(),
75
setgid(), pause(), _exit() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
77
#include <iso646.h> /* not, or, and */
78
#include <argp.h> /* struct argp_option, error_t, struct
79
argp_state, struct argp,
80
argp_parse(), ARGP_KEY_ARG,
81
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
sigaction(), SIGTERM, sig_atomic_t,
84
raise() */
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
87
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
88
WEXITSTATUS(), WTERMSIG() */
89
#include <grp.h> /* setgroups() */
90
#include <argz.h> /* argz_add_sep(), argz_next(),
91
argz_delete(), argz_append(),
92
argz_stringify(), argz_add(),
93
argz_count() */
94
95
#ifdef __linux__
96
#include <sys/klog.h> /* klogctl() */
97
#endif /* __linux__ */
98
99
/* Avahi */
100
/* All Avahi types, constants and functions
101
Avahi*, avahi_*,
102
AVAHI_* */
103
#include <avahi-core/core.h>
104
#include <avahi-core/lookup.h>
105
#include <avahi-core/log.h>
106
#include <avahi-common/simple-watch.h>
107
#include <avahi-common/malloc.h>
108
#include <avahi-common/error.h>
109
110
/* GnuTLS */
111
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
112
functions:
113
gnutls_*
114
init_gnutls_session(),
115
GNUTLS_* */
116
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
119
120
/* GPGME */
121
#include <gpgme.h> /* All GPGME types, constants and
122
functions:
123
gpgme_*
124
GPGME_PROTOCOL_OpenPGP,
125
GPG_ERR_NO_* */
126
127
#define BUFFER_SIZE 256
128
129
#define PATHDIR "/conf/conf.d/mandos"
130
#define SECKEY "seckey.txt"
131
#define PUBKEY "pubkey.txt"
132
#define HOOKDIR "/lib/mandos/network-hooks.d"
133
134
bool debug = false;
135
static const char mandos_protocol_version[] = "1";
136
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
138
static const char sys_class_net[] = "/sys/class/net";
139
char *connect_to = NULL;
140
const char *hookdir = HOOKDIR;
141
uid_t uid = 65534;
142
gid_t gid = 65534;
143
144
/* Doubly linked list that need to be circularly linked when used */
145
typedef struct server{
146
const char *ip;
147
in_port_t port;
148
AvahiIfIndex if_index;
149
int af;
150
struct timespec last_seen;
151
struct server *next;
152
struct server *prev;
153
} server;
154
155
/* Used for passing in values through the Avahi callback functions */
156
typedef struct {
157
AvahiServer *server;
158
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
gnutls_dh_params_t dh_params;
161
const char *priority;
162
gpgme_ctx_t ctx;
163
server *current_server;
164
char *interfaces;
165
size_t interfaces_size;
166
} mandos_context;
167
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
170
171
sig_atomic_t quit_now = 0;
172
int signal_received = 0;
173
174
/* Function to use when printing errors */
175
void perror_plus(const char *print_text){
176
int e = errno;
177
fprintf(stderr, "Mandos plugin %s: ",
178
program_invocation_short_name);
179
errno = e;
180
perror(print_text);
181
}
182
183
__attribute__((format (gnu_printf, 2, 3)))
184
int fprintf_plus(FILE *stream, const char *format, ...){
185
va_list ap;
186
va_start (ap, format);
187
188
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
program_invocation_short_name));
190
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
191
}
192
193
/*
194
* Make additional room in "buffer" for at least BUFFER_SIZE more
195
* bytes. "buffer_capacity" is how much is currently allocated,
196
* "buffer_length" is how much is already used.
197
*/
198
size_t incbuffer(char **buffer, size_t buffer_length,
199
size_t buffer_capacity){
200
if(buffer_length + BUFFER_SIZE > buffer_capacity){
201
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
202
if(buffer == NULL){
203
return 0;
204
}
205
buffer_capacity += BUFFER_SIZE;
206
}
207
return buffer_capacity;
208
}
209
210
/* Add server to set of servers to retry periodically */
211
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
212
int af, server **current_server){
213
int ret;
214
server *new_server = malloc(sizeof(server));
215
if(new_server == NULL){
216
perror_plus("malloc");
217
return false;
218
}
219
*new_server = (server){ .ip = strdup(ip),
220
.port = port,
221
.if_index = if_index,
222
.af = af };
223
if(new_server->ip == NULL){
224
perror_plus("strdup");
225
return false;
226
}
227
/* Special case of first server */
228
if(*current_server == NULL){
229
new_server->next = new_server;
230
new_server->prev = new_server;
231
*current_server = new_server;
232
/* Place the new server last in the list */
233
} else {
234
new_server->next = *current_server;
235
new_server->prev = (*current_server)->prev;
236
new_server->prev->next = new_server;
237
(*current_server)->prev = new_server;
238
}
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
240
if(ret == -1){
241
perror_plus("clock_gettime");
242
return false;
243
}
244
return true;
245
}
246
247
/*
248
* Initialize GPGME.
249
*/
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
252
gpgme_error_t rc;
253
gpgme_engine_info_t engine_info;
254
255
/*
256
* Helper function to insert pub and seckey to the engine keyring.
257
*/
258
bool import_key(const char *filename){
259
int ret;
260
int fd;
261
gpgme_data_t pgp_data;
262
263
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
264
if(fd == -1){
265
perror_plus("open");
266
return false;
267
}
268
269
rc = gpgme_data_new_from_fd(&pgp_data, fd);
270
if(rc != GPG_ERR_NO_ERROR){
271
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
272
gpgme_strsource(rc), gpgme_strerror(rc));
273
return false;
274
}
275
276
rc = gpgme_op_import(mc->ctx, pgp_data);
277
if(rc != GPG_ERR_NO_ERROR){
278
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
280
return false;
281
}
282
283
ret = (int)TEMP_FAILURE_RETRY(close(fd));
284
if(ret == -1){
285
perror_plus("close");
286
}
287
gpgme_data_release(pgp_data);
288
return true;
289
}
290
291
if(debug){
292
fprintf_plus(stderr, "Initializing GPGME\n");
293
}
294
295
/* Init GPGME */
296
gpgme_check_version(NULL);
297
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
298
if(rc != GPG_ERR_NO_ERROR){
299
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
301
return false;
302
}
303
304
/* Set GPGME home directory for the OpenPGP engine only */
305
rc = gpgme_get_engine_info(&engine_info);
306
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
309
return false;
310
}
311
while(engine_info != NULL){
312
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
315
break;
316
}
317
engine_info = engine_info->next;
318
}
319
if(engine_info == NULL){
320
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
321
tempdir);
322
return false;
323
}
324
325
/* Create new GPGME "context" */
326
rc = gpgme_new(&(mc->ctx));
327
if(rc != GPG_ERR_NO_ERROR){
328
fprintf_plus(stderr, "Mandos plugin mandos-client: "
329
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
330
gpgme_strerror(rc));
331
return false;
332
}
333
334
if(not import_key(pubkey) or not import_key(seckey)){
335
return false;
336
}
337
338
return true;
339
}
340
341
/*
342
* Decrypt OpenPGP data.
343
* Returns -1 on error
344
*/
345
static ssize_t pgp_packet_decrypt(const char *cryptotext,
346
size_t crypto_size,
347
char **plaintext,
348
mandos_context *mc){
349
gpgme_data_t dh_crypto, dh_plain;
350
gpgme_error_t rc;
351
ssize_t ret;
352
size_t plaintext_capacity = 0;
353
ssize_t plaintext_length = 0;
354
355
if(debug){
356
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
357
}
358
359
/* Create new GPGME data buffer from memory cryptotext */
360
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
361
0);
362
if(rc != GPG_ERR_NO_ERROR){
363
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
364
gpgme_strsource(rc), gpgme_strerror(rc));
365
return -1;
366
}
367
368
/* Create new empty GPGME data buffer for the plaintext */
369
rc = gpgme_data_new(&dh_plain);
370
if(rc != GPG_ERR_NO_ERROR){
371
fprintf_plus(stderr, "Mandos plugin mandos-client: "
372
"bad gpgme_data_new: %s: %s\n",
373
gpgme_strsource(rc), gpgme_strerror(rc));
374
gpgme_data_release(dh_crypto);
375
return -1;
376
}
377
378
/* Decrypt data from the cryptotext data buffer to the plaintext
379
data buffer */
380
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
381
if(rc != GPG_ERR_NO_ERROR){
382
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
383
gpgme_strsource(rc), gpgme_strerror(rc));
384
plaintext_length = -1;
385
if(debug){
386
gpgme_decrypt_result_t result;
387
result = gpgme_op_decrypt_result(mc->ctx);
388
if(result == NULL){
389
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
390
} else {
391
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
392
result->unsupported_algorithm);
393
fprintf_plus(stderr, "Wrong key usage: %u\n",
394
result->wrong_key_usage);
395
if(result->file_name != NULL){
396
fprintf_plus(stderr, "File name: %s\n", result->file_name);
397
}
398
gpgme_recipient_t recipient;
399
recipient = result->recipients;
400
while(recipient != NULL){
401
fprintf_plus(stderr, "Public key algorithm: %s\n",
402
gpgme_pubkey_algo_name
403
(recipient->pubkey_algo));
404
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
405
fprintf_plus(stderr, "Secret key available: %s\n",
406
recipient->status == GPG_ERR_NO_SECKEY
407
? "No" : "Yes");
408
recipient = recipient->next;
409
}
410
}
411
}
412
goto decrypt_end;
413
}
414
415
if(debug){
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
417
}
418
419
/* Seek back to the beginning of the GPGME plaintext data buffer */
420
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
421
perror_plus("gpgme_data_seek");
422
plaintext_length = -1;
423
goto decrypt_end;
424
}
425
426
*plaintext = NULL;
427
while(true){
428
plaintext_capacity = incbuffer(plaintext,
429
(size_t)plaintext_length,
430
plaintext_capacity);
431
if(plaintext_capacity == 0){
432
perror_plus("incbuffer");
433
plaintext_length = -1;
434
goto decrypt_end;
435
}
436
437
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
438
BUFFER_SIZE);
439
/* Print the data, if any */
440
if(ret == 0){
441
/* EOF */
442
break;
443
}
444
if(ret < 0){
445
perror_plus("gpgme_data_read");
446
plaintext_length = -1;
447
goto decrypt_end;
448
}
449
plaintext_length += ret;
450
}
451
452
if(debug){
453
fprintf_plus(stderr, "Decrypted password is: ");
454
for(ssize_t i = 0; i < plaintext_length; i++){
455
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
456
}
457
fprintf(stderr, "\n");
458
}
459
460
decrypt_end:
461
462
/* Delete the GPGME cryptotext data buffer */
463
gpgme_data_release(dh_crypto);
464
465
/* Delete the GPGME plaintext data buffer */
466
gpgme_data_release(dh_plain);
467
return plaintext_length;
468
}
469
470
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
472
if(ret == NULL)
473
ret = "(unknown)";
474
return ret;
475
}
476
477
/* GnuTLS log function callback */
478
static void debuggnutls(__attribute__((unused)) int level,
479
const char* string){
480
fprintf_plus(stderr, "GnuTLS: %s", string);
481
}
482
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename,
485
mandos_context *mc){
486
int ret;
487
488
if(debug){
489
fprintf_plus(stderr, "Initializing GnuTLS\n");
490
}
491
492
ret = gnutls_global_init();
493
if(ret != GNUTLS_E_SUCCESS){
494
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
495
safer_gnutls_strerror(ret));
496
return -1;
497
}
498
499
if(debug){
500
/* "Use a log level over 10 to enable all debugging options."
501
* - GnuTLS manual
502
*/
503
gnutls_global_set_log_level(11);
504
gnutls_global_set_log_function(debuggnutls);
505
}
506
507
/* OpenPGP credentials */
508
ret = gnutls_certificate_allocate_credentials(&mc->cred);
509
if(ret != GNUTLS_E_SUCCESS){
510
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
511
safer_gnutls_strerror(ret));
512
gnutls_global_deinit();
513
return -1;
514
}
515
516
if(debug){
517
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
518
" secret key %s as GnuTLS credentials\n",
519
pubkeyfilename,
520
seckeyfilename);
521
}
522
523
ret = gnutls_certificate_set_openpgp_key_file
524
(mc->cred, pubkeyfilename, seckeyfilename,
525
GNUTLS_OPENPGP_FMT_BASE64);
526
if(ret != GNUTLS_E_SUCCESS){
527
fprintf_plus(stderr,
528
"Error[%d] while reading the OpenPGP key pair ('%s',"
529
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
530
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
531
safer_gnutls_strerror(ret));
532
goto globalfail;
533
}
534
535
/* GnuTLS server initialization */
536
ret = gnutls_dh_params_init(&mc->dh_params);
537
if(ret != GNUTLS_E_SUCCESS){
538
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
539
" initialization: %s\n",
540
safer_gnutls_strerror(ret));
541
goto globalfail;
542
}
543
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
544
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
546
safer_gnutls_strerror(ret));
547
goto globalfail;
548
}
549
550
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
551
552
return 0;
553
554
globalfail:
555
556
gnutls_certificate_free_credentials(mc->cred);
557
gnutls_global_deinit();
558
gnutls_dh_params_deinit(mc->dh_params);
559
return -1;
560
}
561
562
static int init_gnutls_session(gnutls_session_t *session,
563
mandos_context *mc){
564
int ret;
565
/* GnuTLS session creation */
566
do {
567
ret = gnutls_init(session, GNUTLS_SERVER);
568
if(quit_now){
569
return -1;
570
}
571
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
572
if(ret != GNUTLS_E_SUCCESS){
573
fprintf_plus(stderr,
574
"Error in GnuTLS session initialization: %s\n",
575
safer_gnutls_strerror(ret));
576
}
577
578
{
579
const char *err;
580
do {
581
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
582
if(quit_now){
583
gnutls_deinit(*session);
584
return -1;
585
}
586
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
587
if(ret != GNUTLS_E_SUCCESS){
588
fprintf_plus(stderr, "Syntax error at: %s\n", err);
589
fprintf_plus(stderr, "GnuTLS error: %s\n",
590
safer_gnutls_strerror(ret));
591
gnutls_deinit(*session);
592
return -1;
593
}
594
}
595
596
do {
597
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
598
mc->cred);
599
if(quit_now){
600
gnutls_deinit(*session);
601
return -1;
602
}
603
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
604
if(ret != GNUTLS_E_SUCCESS){
605
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
606
safer_gnutls_strerror(ret));
607
gnutls_deinit(*session);
608
return -1;
609
}
610
611
/* ignore client certificate if any. */
612
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
613
614
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
615
616
return 0;
617
}
618
619
/* Avahi log function callback */
620
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
621
__attribute__((unused)) const char *txt){}
622
623
/* Called when a Mandos server is found */
624
static int start_mandos_communication(const char *ip, in_port_t port,
625
AvahiIfIndex if_index,
626
int af, mandos_context *mc){
627
int ret, tcp_sd = -1;
628
ssize_t sret;
629
union {
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
632
} to;
633
char *buffer = NULL;
634
char *decrypted_buffer = NULL;
635
size_t buffer_length = 0;
636
size_t buffer_capacity = 0;
637
size_t written;
638
int retval = -1;
639
gnutls_session_t session;
640
int pf; /* Protocol family */
641
642
errno = 0;
643
644
if(quit_now){
645
errno = EINTR;
646
return -1;
647
}
648
649
switch(af){
650
case AF_INET6:
651
pf = PF_INET6;
652
break;
653
case AF_INET:
654
pf = PF_INET;
655
break;
656
default:
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
658
errno = EINVAL;
659
return -1;
660
}
661
662
/* If the interface is specified and we have a list of interfaces */
663
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
664
/* Check if the interface is one of the interfaces we are using */
665
bool match = false;
666
{
667
char *interface = NULL;
668
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
669
interface))){
670
if(if_nametoindex(interface) == (unsigned int)if_index){
671
match = true;
672
break;
673
}
674
}
675
}
676
if(not match){
677
/* This interface does not match any in the list, so we don't
678
connect to the server */
679
if(debug){
680
char interface[IF_NAMESIZE];
681
if(if_indextoname((unsigned int)if_index, interface) == NULL){
682
perror_plus("if_indextoname");
683
} else {
684
fprintf_plus(stderr, "Skipping server on non-used interface"
685
" \"%s\"\n",
686
if_indextoname((unsigned int)if_index,
687
interface));
688
}
689
}
690
return -1;
691
}
692
}
693
694
ret = init_gnutls_session(&session, mc);
695
if(ret != 0){
696
return -1;
697
}
698
699
if(debug){
700
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
702
}
703
704
tcp_sd = socket(pf, SOCK_STREAM, 0);
705
if(tcp_sd < 0){
706
int e = errno;
707
perror_plus("socket");
708
errno = e;
709
goto mandos_end;
710
}
711
712
if(quit_now){
713
errno = EINTR;
714
goto mandos_end;
715
}
716
717
memset(&to, 0, sizeof(to));
718
if(af == AF_INET6){
719
to.in6.sin6_family = (sa_family_t)af;
720
ret = inet_pton(af, ip, &to.in6.sin6_addr);
721
} else { /* IPv4 */
722
to.in.sin_family = (sa_family_t)af;
723
ret = inet_pton(af, ip, &to.in.sin_addr);
724
}
725
if(ret < 0 ){
726
int e = errno;
727
perror_plus("inet_pton");
728
errno = e;
729
goto mandos_end;
730
}
731
if(ret == 0){
732
int e = errno;
733
fprintf_plus(stderr, "Bad address: %s\n", ip);
734
errno = e;
735
goto mandos_end;
736
}
737
if(af == AF_INET6){
738
to.in6.sin6_port = htons(port);
739
#ifdef __GNUC__
740
#pragma GCC diagnostic push
741
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
742
#endif
743
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
744
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */
745
#ifdef __GNUC__
746
#pragma GCC diagnostic pop
747
#endif
748
if(if_index == AVAHI_IF_UNSPEC){
749
fprintf_plus(stderr, "An IPv6 link-local address is"
750
" incomplete without a network interface\n");
751
errno = EINVAL;
752
goto mandos_end;
753
}
754
/* Set the network interface number as scope */
755
to.in6.sin6_scope_id = (uint32_t)if_index;
756
}
757
} else {
758
to.in.sin_port = htons(port);
759
}
760
761
if(quit_now){
762
errno = EINTR;
763
goto mandos_end;
764
}
765
766
if(debug){
767
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
768
char interface[IF_NAMESIZE];
769
if(if_indextoname((unsigned int)if_index, interface) == NULL){
770
perror_plus("if_indextoname");
771
} else {
772
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
773
"\n", ip, interface, (uintmax_t)port);
774
}
775
} else {
776
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
777
ip, (uintmax_t)port);
778
}
779
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
780
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
781
const char *pcret;
782
if(af == AF_INET6){
783
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
784
sizeof(addrstr));
785
} else {
786
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
787
sizeof(addrstr));
788
}
789
if(pcret == NULL){
790
perror_plus("inet_ntop");
791
} else {
792
if(strcmp(addrstr, ip) != 0){
793
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
794
}
795
}
796
}
797
798
if(quit_now){
799
errno = EINTR;
800
goto mandos_end;
801
}
802
803
if(af == AF_INET6){
804
ret = connect(tcp_sd, &to.in6, sizeof(to));
805
} else {
806
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
807
}
808
if(ret < 0){
809
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
810
int e = errno;
811
perror_plus("connect");
812
errno = e;
813
}
814
goto mandos_end;
815
}
816
817
if(quit_now){
818
errno = EINTR;
819
goto mandos_end;
820
}
821
822
const char *out = mandos_protocol_version;
823
written = 0;
824
while(true){
825
size_t out_size = strlen(out);
826
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
827
out_size - written));
828
if(ret == -1){
829
int e = errno;
830
perror_plus("write");
831
errno = e;
832
goto mandos_end;
833
}
834
written += (size_t)ret;
835
if(written < out_size){
836
continue;
837
} else {
838
if(out == mandos_protocol_version){
839
written = 0;
840
out = "\r\n";
841
} else {
842
break;
843
}
844
}
845
846
if(quit_now){
847
errno = EINTR;
848
goto mandos_end;
849
}
850
}
851
852
if(debug){
853
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
854
}
855
856
if(quit_now){
857
errno = EINTR;
858
goto mandos_end;
859
}
860
861
/* This casting via intptr_t is to eliminate warning about casting
862
an int to a pointer type. This is exactly how the GnuTLS Guile
863
function "set-session-transport-fd!" does it. */
864
gnutls_transport_set_ptr(session,
865
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
866
867
if(quit_now){
868
errno = EINTR;
869
goto mandos_end;
870
}
871
872
do {
873
ret = gnutls_handshake(session);
874
if(quit_now){
875
errno = EINTR;
876
goto mandos_end;
877
}
878
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
879
880
if(ret != GNUTLS_E_SUCCESS){
881
if(debug){
882
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
883
gnutls_perror(ret);
884
}
885
errno = EPROTO;
886
goto mandos_end;
887
}
888
889
/* Read OpenPGP packet that contains the wanted password */
890
891
if(debug){
892
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
893
" %s\n", ip);
894
}
895
896
while(true){
897
898
if(quit_now){
899
errno = EINTR;
900
goto mandos_end;
901
}
902
903
buffer_capacity = incbuffer(&buffer, buffer_length,
904
buffer_capacity);
905
if(buffer_capacity == 0){
906
int e = errno;
907
perror_plus("incbuffer");
908
errno = e;
909
goto mandos_end;
910
}
911
912
if(quit_now){
913
errno = EINTR;
914
goto mandos_end;
915
}
916
917
sret = gnutls_record_recv(session, buffer+buffer_length,
918
BUFFER_SIZE);
919
if(sret == 0){
920
break;
921
}
922
if(sret < 0){
923
switch(sret){
924
case GNUTLS_E_INTERRUPTED:
925
case GNUTLS_E_AGAIN:
926
break;
927
case GNUTLS_E_REHANDSHAKE:
928
do {
929
ret = gnutls_handshake(session);
930
931
if(quit_now){
932
errno = EINTR;
933
goto mandos_end;
934
}
935
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
936
if(ret < 0){
937
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
938
"***\n");
939
gnutls_perror(ret);
940
errno = EPROTO;
941
goto mandos_end;
942
}
943
break;
944
default:
945
fprintf_plus(stderr, "Unknown error while reading data from"
946
" encrypted session with Mandos server\n");
947
gnutls_bye(session, GNUTLS_SHUT_RDWR);
948
errno = EIO;
949
goto mandos_end;
950
}
951
} else {
952
buffer_length += (size_t) sret;
953
}
954
}
955
956
if(debug){
957
fprintf_plus(stderr, "Closing TLS session\n");
958
}
959
960
if(quit_now){
961
errno = EINTR;
962
goto mandos_end;
963
}
964
965
do {
966
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
967
if(quit_now){
968
errno = EINTR;
969
goto mandos_end;
970
}
971
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
972
973
if(buffer_length > 0){
974
ssize_t decrypted_buffer_size;
975
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
976
&decrypted_buffer, mc);
977
if(decrypted_buffer_size >= 0){
978
979
written = 0;
980
while(written < (size_t) decrypted_buffer_size){
981
if(quit_now){
982
errno = EINTR;
983
goto mandos_end;
984
}
985
986
ret = (int)fwrite(decrypted_buffer + written, 1,
987
(size_t)decrypted_buffer_size - written,
988
stdout);
989
if(ret == 0 and ferror(stdout)){
990
int e = errno;
991
if(debug){
992
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
993
strerror(errno));
994
}
995
errno = e;
996
goto mandos_end;
997
}
998
written += (size_t)ret;
999
}
1000
retval = 0;
1001
}
1002
}
1003
1004
/* Shutdown procedure */
1005
1006
mandos_end:
1007
{
1008
int e = errno;
1009
free(decrypted_buffer);
1010
free(buffer);
1011
if(tcp_sd >= 0){
1012
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1013
}
1014
if(ret == -1){
1015
if(e == 0){
1016
e = errno;
1017
}
1018
perror_plus("close");
1019
}
1020
gnutls_deinit(session);
1021
errno = e;
1022
if(quit_now){
1023
errno = EINTR;
1024
retval = -1;
1025
}
1026
}
1027
return retval;
1028
}
1029
1030
static void resolve_callback(AvahiSServiceResolver *r,
1031
AvahiIfIndex interface,
1032
AvahiProtocol proto,
1033
AvahiResolverEvent event,
1034
const char *name,
1035
const char *type,
1036
const char *domain,
1037
const char *host_name,
1038
const AvahiAddress *address,
1039
uint16_t port,
1040
AVAHI_GCC_UNUSED AvahiStringList *txt,
1041
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1042
flags,
1043
void* mc){
1044
if(r == NULL){
1045
return;
1046
}
1047
1048
/* Called whenever a service has been resolved successfully or
1049
timed out */
1050
1051
if(quit_now){
1052
return;
1053
}
1054
1055
switch(event){
1056
default:
1057
case AVAHI_RESOLVER_FAILURE:
1058
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1059
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1060
domain,
1061
avahi_strerror(avahi_server_errno
1062
(((mandos_context*)mc)->server)));
1063
break;
1064
1065
case AVAHI_RESOLVER_FOUND:
1066
{
1067
char ip[AVAHI_ADDRESS_STR_MAX];
1068
avahi_address_snprint(ip, sizeof(ip), address);
1069
if(debug){
1070
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1071
PRIdMAX ") on port %" PRIu16 "\n", name,
1072
host_name, ip, (intmax_t)interface, port);
1073
}
1074
int ret = start_mandos_communication(ip, (in_port_t)port,
1075
interface,
1076
avahi_proto_to_af(proto),
1077
mc);
1078
if(ret == 0){
1079
avahi_simple_poll_quit(simple_poll);
1080
} else {
1081
if(not add_server(ip, (in_port_t)port, interface,
1082
avahi_proto_to_af(proto),
1083
&((mandos_context*)mc)->current_server)){
1084
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1085
" list\n", name);
1086
}
1087
}
1088
}
1089
}
1090
avahi_s_service_resolver_free(r);
1091
}
1092
1093
static void browse_callback(AvahiSServiceBrowser *b,
1094
AvahiIfIndex interface,
1095
AvahiProtocol protocol,
1096
AvahiBrowserEvent event,
1097
const char *name,
1098
const char *type,
1099
const char *domain,
1100
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1101
flags,
1102
void* mc){
1103
if(b == NULL){
1104
return;
1105
}
1106
1107
/* Called whenever a new services becomes available on the LAN or
1108
is removed from the LAN */
1109
1110
if(quit_now){
1111
return;
1112
}
1113
1114
switch(event){
1115
default:
1116
case AVAHI_BROWSER_FAILURE:
1117
1118
fprintf_plus(stderr, "(Avahi browser) %s\n",
1119
avahi_strerror(avahi_server_errno
1120
(((mandos_context*)mc)->server)));
1121
avahi_simple_poll_quit(simple_poll);
1122
return;
1123
1124
case AVAHI_BROWSER_NEW:
1125
/* We ignore the returned Avahi resolver object. In the callback
1126
function we free it. If the Avahi server is terminated before
1127
the callback function is called the Avahi server will free the
1128
resolver for us. */
1129
1130
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1131
interface, protocol, name, type,
1132
domain, protocol, 0,
1133
resolve_callback, mc) == NULL)
1134
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1135
" %s\n", name,
1136
avahi_strerror(avahi_server_errno
1137
(((mandos_context*)mc)->server)));
1138
break;
1139
1140
case AVAHI_BROWSER_REMOVE:
1141
break;
1142
1143
case AVAHI_BROWSER_ALL_FOR_NOW:
1144
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1145
if(debug){
1146
fprintf_plus(stderr, "No Mandos server found, still"
1147
" searching...\n");
1148
}
1149
break;
1150
}
1151
}
1152
1153
/* Signal handler that stops main loop after SIGTERM */
1154
static void handle_sigterm(int sig){
1155
if(quit_now){
1156
return;
1157
}
1158
quit_now = 1;
1159
signal_received = sig;
1160
int old_errno = errno;
1161
/* set main loop to exit */
1162
if(simple_poll != NULL){
1163
avahi_simple_poll_quit(simple_poll);
1164
}
1165
errno = old_errno;
1166
}
1167
1168
bool get_flags(const char *ifname, struct ifreq *ifr){
1169
int ret;
1170
error_t ret_errno;
1171
1172
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1173
if(s < 0){
1174
ret_errno = errno;
1175
perror_plus("socket");
1176
errno = ret_errno;
1177
return false;
1178
}
1179
strcpy(ifr->ifr_name, ifname);
1180
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1181
if(ret == -1){
1182
if(debug){
1183
ret_errno = errno;
1184
perror_plus("ioctl SIOCGIFFLAGS");
1185
errno = ret_errno;
1186
}
1187
return false;
1188
}
1189
return true;
1190
}
1191
1192
bool good_flags(const char *ifname, const struct ifreq *ifr){
1193
1194
/* Reject the loopback device */
1195
if(ifr->ifr_flags & IFF_LOOPBACK){
1196
if(debug){
1197
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1198
ifname);
1199
}
1200
return false;
1201
}
1202
/* Accept point-to-point devices only if connect_to is specified */
1203
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1204
if(debug){
1205
fprintf_plus(stderr, "Accepting point-to-point interface"
1206
" \"%s\"\n", ifname);
1207
}
1208
return true;
1209
}
1210
/* Otherwise, reject non-broadcast-capable devices */
1211
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1212
if(debug){
1213
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1214
" \"%s\"\n", ifname);
1215
}
1216
return false;
1217
}
1218
/* Reject non-ARP interfaces (including dummy interfaces) */
1219
if(ifr->ifr_flags & IFF_NOARP){
1220
if(debug){
1221
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1222
ifname);
1223
}
1224
return false;
1225
}
1226
1227
/* Accept this device */
1228
if(debug){
1229
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1230
}
1231
return true;
1232
}
1233
1234
/*
1235
* This function determines if a directory entry in /sys/class/net
1236
* corresponds to an acceptable network device.
1237
* (This function is passed to scandir(3) as a filter function.)
1238
*/
1239
int good_interface(const struct dirent *if_entry){
1240
if(if_entry->d_name[0] == '.'){
1241
return 0;
1242
}
1243
1244
struct ifreq ifr;
1245
if(not get_flags(if_entry->d_name, &ifr)){
1246
if(debug){
1247
fprintf_plus(stderr, "Failed to get flags for interface "
1248
"\"%s\"\n", if_entry->d_name);
1249
}
1250
return 0;
1251
}
1252
1253
if(not good_flags(if_entry->d_name, &ifr)){
1254
return 0;
1255
}
1256
return 1;
1257
}
1258
1259
/*
1260
* This function determines if a network interface is up.
1261
*/
1262
bool interface_is_up(const char *interface){
1263
struct ifreq ifr;
1264
if(not get_flags(interface, &ifr)){
1265
if(debug){
1266
fprintf_plus(stderr, "Failed to get flags for interface "
1267
"\"%s\"\n", interface);
1268
}
1269
return false;
1270
}
1271
1272
return (bool)(ifr.ifr_flags & IFF_UP);
1273
}
1274
1275
/*
1276
* This function determines if a network interface is running
1277
*/
1278
bool interface_is_running(const char *interface){
1279
struct ifreq ifr;
1280
if(not get_flags(interface, &ifr)){
1281
if(debug){
1282
fprintf_plus(stderr, "Failed to get flags for interface "
1283
"\"%s\"\n", interface);
1284
}
1285
return false;
1286
}
1287
1288
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1289
}
1290
1291
int notdotentries(const struct dirent *direntry){
1292
/* Skip "." and ".." */
1293
if(direntry->d_name[0] == '.'
1294
and (direntry->d_name[1] == '\0'
1295
or (direntry->d_name[1] == '.'
1296
and direntry->d_name[2] == '\0'))){
1297
return 0;
1298
}
1299
return 1;
1300
}
1301
1302
/* Is this directory entry a runnable program? */
1303
int runnable_hook(const struct dirent *direntry){
1304
int ret;
1305
size_t sret;
1306
struct stat st;
1307
1308
if((direntry->d_name)[0] == '\0'){
1309
/* Empty name? */
1310
return 0;
1311
}
1312
1313
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1314
"abcdefghijklmnopqrstuvwxyz"
1315
"0123456789"
1316
"_-");
1317
if((direntry->d_name)[sret] != '\0'){
1318
/* Contains non-allowed characters */
1319
if(debug){
1320
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1321
direntry->d_name);
1322
}
1323
return 0;
1324
}
1325
1326
char *fullname = NULL;
1327
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1328
if(ret < 0){
1329
perror_plus("asprintf");
1330
return 0;
1331
}
1332
1333
ret = stat(fullname, &st);
1334
if(ret == -1){
1335
if(debug){
1336
perror_plus("Could not stat hook");
1337
}
1338
return 0;
1339
}
1340
if(not (S_ISREG(st.st_mode))){
1341
/* Not a regular file */
1342
if(debug){
1343
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1344
direntry->d_name);
1345
}
1346
return 0;
1347
}
1348
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1349
/* Not executable */
1350
if(debug){
1351
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1352
direntry->d_name);
1353
}
1354
return 0;
1355
}
1356
if(debug){
1357
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1358
direntry->d_name);
1359
}
1360
return 1;
1361
}
1362
1363
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1364
mandos_context *mc){
1365
int ret;
1366
struct timespec now;
1367
struct timespec waited_time;
1368
intmax_t block_time;
1369
1370
while(true){
1371
if(mc->current_server == NULL){
1372
if (debug){
1373
fprintf_plus(stderr, "Wait until first server is found."
1374
" No timeout!\n");
1375
}
1376
ret = avahi_simple_poll_iterate(s, -1);
1377
} else {
1378
if (debug){
1379
fprintf_plus(stderr, "Check current_server if we should run"
1380
" it, or wait\n");
1381
}
1382
/* the current time */
1383
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1384
if(ret == -1){
1385
perror_plus("clock_gettime");
1386
return -1;
1387
}
1388
/* Calculating in ms how long time between now and server
1389
who we visted longest time ago. Now - last seen. */
1390
waited_time.tv_sec = (now.tv_sec
1391
- mc->current_server->last_seen.tv_sec);
1392
waited_time.tv_nsec = (now.tv_nsec
1393
- mc->current_server->last_seen.tv_nsec);
1394
/* total time is 10s/10,000ms.
1395
Converting to s from ms by dividing by 1,000,
1396
and ns to ms by dividing by 1,000,000. */
1397
block_time = ((retry_interval
1398
- ((intmax_t)waited_time.tv_sec * 1000))
1399
- ((intmax_t)waited_time.tv_nsec / 1000000));
1400
1401
if (debug){
1402
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1403
block_time);
1404
}
1405
1406
if(block_time <= 0){
1407
ret = start_mandos_communication(mc->current_server->ip,
1408
mc->current_server->port,
1409
mc->current_server->if_index,
1410
mc->current_server->af, mc);
1411
if(ret == 0){
1412
avahi_simple_poll_quit(s);
1413
return 0;
1414
}
1415
ret = clock_gettime(CLOCK_MONOTONIC,
1416
&mc->current_server->last_seen);
1417
if(ret == -1){
1418
perror_plus("clock_gettime");
1419
return -1;
1420
}
1421
mc->current_server = mc->current_server->next;
1422
block_time = 0; /* Call avahi to find new Mandos
1423
servers, but don't block */
1424
}
1425
1426
ret = avahi_simple_poll_iterate(s, (int)block_time);
1427
}
1428
if(ret != 0){
1429
if (ret > 0 or errno != EINTR){
1430
return (ret != 1) ? ret : 0;
1431
}
1432
}
1433
}
1434
}
1435
1436
/* Set effective uid to 0, return errno */
1437
error_t raise_privileges(void){
1438
error_t old_errno = errno;
1439
error_t ret_errno = 0;
1440
if(seteuid(0) == -1){
1441
ret_errno = errno;
1442
perror_plus("seteuid");
1443
}
1444
errno = old_errno;
1445
return ret_errno;
1446
}
1447
1448
/* Set effective and real user ID to 0. Return errno. */
1449
error_t raise_privileges_permanently(void){
1450
error_t old_errno = errno;
1451
error_t ret_errno = raise_privileges();
1452
if(ret_errno != 0){
1453
errno = old_errno;
1454
return ret_errno;
1455
}
1456
if(setuid(0) == -1){
1457
ret_errno = errno;
1458
perror_plus("seteuid");
1459
}
1460
errno = old_errno;
1461
return ret_errno;
1462
}
1463
1464
/* Set effective user ID to unprivileged saved user ID */
1465
error_t lower_privileges(void){
1466
error_t old_errno = errno;
1467
error_t ret_errno = 0;
1468
if(seteuid(uid) == -1){
1469
ret_errno = errno;
1470
perror_plus("seteuid");
1471
}
1472
errno = old_errno;
1473
return ret_errno;
1474
}
1475
1476
/* Lower privileges permanently */
1477
error_t lower_privileges_permanently(void){
1478
error_t old_errno = errno;
1479
error_t ret_errno = 0;
1480
if(setuid(uid) == -1){
1481
ret_errno = errno;
1482
perror_plus("setuid");
1483
}
1484
errno = old_errno;
1485
return ret_errno;
1486
}
1487
1488
bool run_network_hooks(const char *mode, const char *interface,
1489
const float delay){
1490
struct dirent **direntries;
1491
struct dirent *direntry;
1492
int ret;
1493
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1494
alphasort);
1495
if(numhooks == -1){
1496
if(errno == ENOENT){
1497
if(debug){
1498
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1499
" found\n", hookdir);
1500
}
1501
} else {
1502
perror_plus("scandir");
1503
}
1504
} else {
1505
int devnull = open("/dev/null", O_RDONLY);
1506
for(int i = 0; i < numhooks; i++){
1507
direntry = direntries[i];
1508
char *fullname = NULL;
1509
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1510
if(ret < 0){
1511
perror_plus("asprintf");
1512
continue;
1513
}
1514
if(debug){
1515
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1516
direntry->d_name);
1517
}
1518
pid_t hook_pid = fork();
1519
if(hook_pid == 0){
1520
/* Child */
1521
/* Raise privileges */
1522
raise_privileges_permanently();
1523
/* Set group */
1524
errno = 0;
1525
ret = setgid(0);
1526
if(ret == -1){
1527
perror_plus("setgid");
1528
}
1529
/* Reset supplementary groups */
1530
errno = 0;
1531
ret = setgroups(0, NULL);
1532
if(ret == -1){
1533
perror_plus("setgroups");
1534
}
1535
dup2(devnull, STDIN_FILENO);
1536
close(devnull);
1537
dup2(STDERR_FILENO, STDOUT_FILENO);
1538
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1539
if(ret == -1){
1540
perror_plus("setenv");
1541
_exit(EX_OSERR);
1542
}
1543
ret = setenv("DEVICE", interface, 1);
1544
if(ret == -1){
1545
perror_plus("setenv");
1546
_exit(EX_OSERR);
1547
}
1548
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1549
if(ret == -1){
1550
perror_plus("setenv");
1551
_exit(EX_OSERR);
1552
}
1553
ret = setenv("MODE", mode, 1);
1554
if(ret == -1){
1555
perror_plus("setenv");
1556
_exit(EX_OSERR);
1557
}
1558
char *delaystring;
1559
ret = asprintf(&delaystring, "%f", delay);
1560
if(ret == -1){
1561
perror_plus("asprintf");
1562
_exit(EX_OSERR);
1563
}
1564
ret = setenv("DELAY", delaystring, 1);
1565
if(ret == -1){
1566
free(delaystring);
1567
perror_plus("setenv");
1568
_exit(EX_OSERR);
1569
}
1570
free(delaystring);
1571
if(connect_to != NULL){
1572
ret = setenv("CONNECT", connect_to, 1);
1573
if(ret == -1){
1574
perror_plus("setenv");
1575
_exit(EX_OSERR);
1576
}
1577
}
1578
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1579
perror_plus("execl");
1580
_exit(EXIT_FAILURE);
1581
}
1582
} else {
1583
int status;
1584
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1585
perror_plus("waitpid");
1586
free(fullname);
1587
continue;
1588
}
1589
if(WIFEXITED(status)){
1590
if(WEXITSTATUS(status) != 0){
1591
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1592
" with status %d\n", direntry->d_name,
1593
WEXITSTATUS(status));
1594
free(fullname);
1595
continue;
1596
}
1597
} else if(WIFSIGNALED(status)){
1598
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1599
" signal %d\n", direntry->d_name,
1600
WTERMSIG(status));
1601
free(fullname);
1602
continue;
1603
} else {
1604
fprintf_plus(stderr, "Warning: network hook \"%s\""
1605
" crashed\n", direntry->d_name);
1606
free(fullname);
1607
continue;
1608
}
1609
}
1610
free(fullname);
1611
if(debug){
1612
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1613
direntry->d_name);
1614
}
1615
}
1616
close(devnull);
1617
}
1618
return true;
1619
}
1620
1621
error_t bring_up_interface(const char *const interface,
1622
const float delay){
1623
int sd = -1;
1624
error_t old_errno = errno;
1625
error_t ret_errno = 0;
1626
int ret, ret_setflags;
1627
struct ifreq network;
1628
unsigned int if_index = if_nametoindex(interface);
1629
if(if_index == 0){
1630
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1631
errno = old_errno;
1632
return ENXIO;
1633
}
1634
1635
if(quit_now){
1636
errno = old_errno;
1637
return EINTR;
1638
}
1639
1640
if(not interface_is_up(interface)){
1641
if(not get_flags(interface, &network) and debug){
1642
ret_errno = errno;
1643
fprintf_plus(stderr, "Failed to get flags for interface "
1644
"\"%s\"\n", interface);
1645
return ret_errno;
1646
}
1647
network.ifr_flags |= IFF_UP;
1648
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1650
if(sd < 0){
1651
ret_errno = errno;
1652
perror_plus("socket");
1653
errno = old_errno;
1654
return ret_errno;
1655
}
1656
1657
if(quit_now){
1658
close(sd);
1659
errno = old_errno;
1660
return EINTR;
1661
}
1662
1663
if(debug){
1664
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1665
interface);
1666
}
1667
1668
/* Raise priviliges */
1669
raise_privileges();
1670
1671
#ifdef __linux__
1672
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1673
messages about the network interface to mess up the prompt */
1674
int ret_linux = klogctl(8, NULL, 5);
1675
bool restore_loglevel = true;
1676
if(ret_linux == -1){
1677
restore_loglevel = false;
1678
perror_plus("klogctl");
1679
}
1680
#endif /* __linux__ */
1681
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1682
ret_errno = errno;
1683
#ifdef __linux__
1684
if(restore_loglevel){
1685
ret_linux = klogctl(7, NULL, 0);
1686
if(ret_linux == -1){
1687
perror_plus("klogctl");
1688
}
1689
}
1690
#endif /* __linux__ */
1691
1692
/* Lower privileges */
1693
lower_privileges();
1694
1695
/* Close the socket */
1696
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1697
if(ret == -1){
1698
perror_plus("close");
1699
}
1700
1701
if(ret_setflags == -1){
1702
errno = ret_errno;
1703
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1704
errno = old_errno;
1705
return ret_errno;
1706
}
1707
} else if(debug){
1708
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1709
interface);
1710
}
1711
1712
/* Sleep checking until interface is running.
1713
Check every 0.25s, up to total time of delay */
1714
for(int i=0; i < delay * 4; i++){
1715
if(interface_is_running(interface)){
1716
break;
1717
}
1718
struct timespec sleeptime = { .tv_nsec = 250000000 };
1719
ret = nanosleep(&sleeptime, NULL);
1720
if(ret == -1 and errno != EINTR){
1721
perror_plus("nanosleep");
1722
}
1723
}
1724
1725
errno = old_errno;
1726
return 0;
1727
}
1728
1729
error_t take_down_interface(const char *const interface){
1730
int sd = -1;
1731
error_t old_errno = errno;
1732
error_t ret_errno = 0;
1733
int ret, ret_setflags;
1734
struct ifreq network;
1735
unsigned int if_index = if_nametoindex(interface);
1736
if(if_index == 0){
1737
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1738
errno = old_errno;
1739
return ENXIO;
1740
}
1741
if(interface_is_up(interface)){
1742
if(not get_flags(interface, &network) and debug){
1743
ret_errno = errno;
1744
fprintf_plus(stderr, "Failed to get flags for interface "
1745
"\"%s\"\n", interface);
1746
return ret_errno;
1747
}
1748
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1749
1750
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1751
if(sd < 0){
1752
ret_errno = errno;
1753
perror_plus("socket");
1754
errno = old_errno;
1755
return ret_errno;
1756
}
1757
1758
if(debug){
1759
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1760
interface);
1761
}
1762
1763
/* Raise priviliges */
1764
raise_privileges();
1765
1766
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1767
ret_errno = errno;
1768
1769
/* Lower privileges */
1770
lower_privileges();
1771
1772
/* Close the socket */
1773
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1774
if(ret == -1){
1775
perror_plus("close");
1776
}
1777
1778
if(ret_setflags == -1){
1779
errno = ret_errno;
1780
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1781
errno = old_errno;
1782
return ret_errno;
1783
}
1784
} else if(debug){
1785
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1786
interface);
1787
}
1788
1789
errno = old_errno;
1790
return 0;
1791
}
1792
1793
int main(int argc, char *argv[]){
1794
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1795
.priority = "SECURE256:!CTYPE-X.509:"
1796
"+CTYPE-OPENPGP", .current_server = NULL,
1797
.interfaces = NULL, .interfaces_size = 0 };
1798
AvahiSServiceBrowser *sb = NULL;
1799
error_t ret_errno;
1800
int ret;
1801
intmax_t tmpmax;
1802
char *tmp;
1803
int exitcode = EXIT_SUCCESS;
1804
char *interfaces_to_take_down = NULL;
1805
size_t interfaces_to_take_down_size = 0;
1806
char tempdir[] = "/tmp/mandosXXXXXX";
1807
bool tempdir_created = false;
1808
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1809
const char *seckey = PATHDIR "/" SECKEY;
1810
const char *pubkey = PATHDIR "/" PUBKEY;
1811
char *interfaces_hooks = NULL;
1812
size_t interfaces_hooks_size = 0;
1813
1814
bool gnutls_initialized = false;
1815
bool gpgme_initialized = false;
1816
float delay = 2.5f;
1817
double retry_interval = 10; /* 10s between trying a server and
1818
retrying the same server again */
1819
1820
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1821
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1822
1823
uid = getuid();
1824
gid = getgid();
1825
1826
/* Lower any group privileges we might have, just to be safe */
1827
errno = 0;
1828
ret = setgid(gid);
1829
if(ret == -1){
1830
perror_plus("setgid");
1831
}
1832
1833
/* Lower user privileges (temporarily) */
1834
errno = 0;
1835
ret = seteuid(uid);
1836
if(ret == -1){
1837
perror_plus("seteuid");
1838
}
1839
1840
if(quit_now){
1841
goto end;
1842
}
1843
1844
{
1845
struct argp_option options[] = {
1846
{ .name = "debug", .key = 128,
1847
.doc = "Debug mode", .group = 3 },
1848
{ .name = "connect", .key = 'c',
1849
.arg = "ADDRESS:PORT",
1850
.doc = "Connect directly to a specific Mandos server",
1851
.group = 1 },
1852
{ .name = "interface", .key = 'i',
1853
.arg = "NAME",
1854
.doc = "Network interface that will be used to search for"
1855
" Mandos servers",
1856
.group = 1 },
1857
{ .name = "seckey", .key = 's',
1858
.arg = "FILE",
1859
.doc = "OpenPGP secret key file base name",
1860
.group = 1 },
1861
{ .name = "pubkey", .key = 'p',
1862
.arg = "FILE",
1863
.doc = "OpenPGP public key file base name",
1864
.group = 2 },
1865
{ .name = "dh-bits", .key = 129,
1866
.arg = "BITS",
1867
.doc = "Bit length of the prime number used in the"
1868
" Diffie-Hellman key exchange",
1869
.group = 2 },
1870
{ .name = "priority", .key = 130,
1871
.arg = "STRING",
1872
.doc = "GnuTLS priority string for the TLS handshake",
1873
.group = 1 },
1874
{ .name = "delay", .key = 131,
1875
.arg = "SECONDS",
1876
.doc = "Maximum delay to wait for interface startup",
1877
.group = 2 },
1878
{ .name = "retry", .key = 132,
1879
.arg = "SECONDS",
1880
.doc = "Retry interval used when denied by the Mandos server",
1881
.group = 2 },
1882
{ .name = "network-hook-dir", .key = 133,
1883
.arg = "DIR",
1884
.doc = "Directory where network hooks are located",
1885
.group = 2 },
1886
/*
1887
* These reproduce what we would get without ARGP_NO_HELP
1888
*/
1889
{ .name = "help", .key = '?',
1890
.doc = "Give this help list", .group = -1 },
1891
{ .name = "usage", .key = -3,
1892
.doc = "Give a short usage message", .group = -1 },
1893
{ .name = "version", .key = 'V',
1894
.doc = "Print program version", .group = -1 },
1895
{ .name = NULL }
1896
};
1897
1898
error_t parse_opt(int key, char *arg,
1899
struct argp_state *state){
1900
errno = 0;
1901
switch(key){
1902
case 128: /* --debug */
1903
debug = true;
1904
break;
1905
case 'c': /* --connect */
1906
connect_to = arg;
1907
break;
1908
case 'i': /* --interface */
1909
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1910
arg, (int)',');
1911
if(ret_errno != 0){
1912
argp_error(state, "%s", strerror(ret_errno));
1913
}
1914
break;
1915
case 's': /* --seckey */
1916
seckey = arg;
1917
break;
1918
case 'p': /* --pubkey */
1919
pubkey = arg;
1920
break;
1921
case 129: /* --dh-bits */
1922
errno = 0;
1923
tmpmax = strtoimax(arg, &tmp, 10);
1924
if(errno != 0 or tmp == arg or *tmp != '\0'
1925
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1926
argp_error(state, "Bad number of DH bits");
1927
}
1928
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1929
break;
1930
case 130: /* --priority */
1931
mc.priority = arg;
1932
break;
1933
case 131: /* --delay */
1934
errno = 0;
1935
delay = strtof(arg, &tmp);
1936
if(errno != 0 or tmp == arg or *tmp != '\0'){
1937
argp_error(state, "Bad delay");
1938
}
1939
case 132: /* --retry */
1940
errno = 0;
1941
retry_interval = strtod(arg, &tmp);
1942
if(errno != 0 or tmp == arg or *tmp != '\0'
1943
or (retry_interval * 1000) > INT_MAX
1944
or retry_interval < 0){
1945
argp_error(state, "Bad retry interval");
1946
}
1947
break;
1948
case 133: /* --network-hook-dir */
1949
hookdir = arg;
1950
break;
1951
/*
1952
* These reproduce what we would get without ARGP_NO_HELP
1953
*/
1954
case '?': /* --help */
1955
argp_state_help(state, state->out_stream,
1956
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1957
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1958
case -3: /* --usage */
1959
argp_state_help(state, state->out_stream,
1960
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1961
case 'V': /* --version */
1962
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1963
exit(argp_err_exit_status);
1964
break;
1965
default:
1966
return ARGP_ERR_UNKNOWN;
1967
}
1968
return errno;
1969
}
1970
1971
struct argp argp = { .options = options, .parser = parse_opt,
1972
.args_doc = "",
1973
.doc = "Mandos client -- Get and decrypt"
1974
" passwords from a Mandos server" };
1975
ret = argp_parse(&argp, argc, argv,
1976
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1977
switch(ret){
1978
case 0:
1979
break;
1980
case ENOMEM:
1981
default:
1982
errno = ret;
1983
perror_plus("argp_parse");
1984
exitcode = EX_OSERR;
1985
goto end;
1986
case EINVAL:
1987
exitcode = EX_USAGE;
1988
goto end;
1989
}
1990
}
1991
1992
{
1993
/* Work around Debian bug #633582:
1994
<http://bugs.debian.org/633582> */
1995
1996
/* Re-raise priviliges */
1997
if(raise_privileges() == 0){
1998
struct stat st;
1999
2000
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2001
int seckey_fd = open(seckey, O_RDONLY);
2002
if(seckey_fd == -1){
2003
perror_plus("open");
2004
} else {
2005
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2006
if(ret == -1){
2007
perror_plus("fstat");
2008
} else {
2009
if(S_ISREG(st.st_mode)
2010
and st.st_uid == 0 and st.st_gid == 0){
2011
ret = fchown(seckey_fd, uid, gid);
2012
if(ret == -1){
2013
perror_plus("fchown");
2014
}
2015
}
2016
}
2017
TEMP_FAILURE_RETRY(close(seckey_fd));
2018
}
2019
}
2020
2021
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2022
int pubkey_fd = open(pubkey, O_RDONLY);
2023
if(pubkey_fd == -1){
2024
perror_plus("open");
2025
} else {
2026
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2027
if(ret == -1){
2028
perror_plus("fstat");
2029
} else {
2030
if(S_ISREG(st.st_mode)
2031
and st.st_uid == 0 and st.st_gid == 0){
2032
ret = fchown(pubkey_fd, uid, gid);
2033
if(ret == -1){
2034
perror_plus("fchown");
2035
}
2036
}
2037
}
2038
TEMP_FAILURE_RETRY(close(pubkey_fd));
2039
}
2040
}
2041
2042
/* Lower privileges */
2043
lower_privileges();
2044
}
2045
}
2046
2047
/* Remove invalid interface names (except "none") */
2048
{
2049
char *interface = NULL;
2050
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2051
interface))){
2052
if(strcmp(interface, "none") != 0
2053
and if_nametoindex(interface) == 0){
2054
if(interface[0] != '\0'){
2055
fprintf_plus(stderr, "Not using nonexisting interface"
2056
" \"%s\"\n", interface);
2057
}
2058
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2059
interface = NULL;
2060
}
2061
}
2062
}
2063
2064
/* Run network hooks */
2065
{
2066
if(mc.interfaces != NULL){
2067
interfaces_hooks = malloc(mc.interfaces_size);
2068
if(interfaces_hooks == NULL){
2069
perror_plus("malloc");
2070
goto end;
2071
}
2072
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2073
interfaces_hooks_size = mc.interfaces_size;
2074
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2075
(int)',');
2076
}
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
2079
goto end;
2080
}
2081
}
2082
2083
if(not debug){
2084
avahi_set_log_function(empty_log);
2085
}
2086
2087
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2088
from the signal handler */
2089
/* Initialize the pseudo-RNG for Avahi */
2090
srand((unsigned int) time(NULL));
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
2093
fprintf_plus(stderr,
2094
"Avahi: Failed to create simple poll object.\n");
2095
exitcode = EX_UNAVAILABLE;
2096
goto end;
2097
}
2098
2099
sigemptyset(&sigterm_action.sa_mask);
2100
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2101
if(ret == -1){
2102
perror_plus("sigaddset");
2103
exitcode = EX_OSERR;
2104
goto end;
2105
}
2106
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2107
if(ret == -1){
2108
perror_plus("sigaddset");
2109
exitcode = EX_OSERR;
2110
goto end;
2111
}
2112
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2113
if(ret == -1){
2114
perror_plus("sigaddset");
2115
exitcode = EX_OSERR;
2116
goto end;
2117
}
2118
/* Need to check if the handler is SIG_IGN before handling:
2119
| [[info:libc:Initial Signal Actions]] |
2120
| [[info:libc:Basic Signal Handling]] |
2121
*/
2122
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2123
if(ret == -1){
2124
perror_plus("sigaction");
2125
return EX_OSERR;
2126
}
2127
if(old_sigterm_action.sa_handler != SIG_IGN){
2128
ret = sigaction(SIGINT, &sigterm_action, NULL);
2129
if(ret == -1){
2130
perror_plus("sigaction");
2131
exitcode = EX_OSERR;
2132
goto end;
2133
}
2134
}
2135
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2136
if(ret == -1){
2137
perror_plus("sigaction");
2138
return EX_OSERR;
2139
}
2140
if(old_sigterm_action.sa_handler != SIG_IGN){
2141
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2142
if(ret == -1){
2143
perror_plus("sigaction");
2144
exitcode = EX_OSERR;
2145
goto end;
2146
}
2147
}
2148
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2149
if(ret == -1){
2150
perror_plus("sigaction");
2151
return EX_OSERR;
2152
}
2153
if(old_sigterm_action.sa_handler != SIG_IGN){
2154
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2155
if(ret == -1){
2156
perror_plus("sigaction");
2157
exitcode = EX_OSERR;
2158
goto end;
2159
}
2160
}
2161
2162
/* If no interfaces were specified, make a list */
2163
if(mc.interfaces == NULL){
2164
struct dirent **direntries;
2165
/* Look for any good interfaces */
2166
ret = scandir(sys_class_net, &direntries, good_interface,
2167
alphasort);
2168
if(ret >= 1){
2169
/* Add all found interfaces to interfaces list */
2170
for(int i = 0; i < ret; ++i){
2171
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2172
direntries[i]->d_name);
2173
if(ret_errno != 0){
2174
perror_plus("argz_add");
2175
continue;
2176
}
2177
if(debug){
2178
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2179
direntries[i]->d_name);
2180
}
2181
}
2182
free(direntries);
2183
} else {
2184
free(direntries);
2185
fprintf_plus(stderr, "Could not find a network interface\n");
2186
exitcode = EXIT_FAILURE;
2187
goto end;
2188
}
2189
}
2190
2191
/* Bring up interfaces which are down, and remove any "none"s */
2192
{
2193
char *interface = NULL;
2194
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2195
interface))){
2196
/* If interface name is "none", stop bringing up interfaces.
2197
Also remove all instances of "none" from the list */
2198
if(strcmp(interface, "none") == 0){
2199
argz_delete(&mc.interfaces, &mc.interfaces_size,
2200
interface);
2201
interface = NULL;
2202
while((interface = argz_next(mc.interfaces,
2203
mc.interfaces_size, interface))){
2204
if(strcmp(interface, "none") == 0){
2205
argz_delete(&mc.interfaces, &mc.interfaces_size,
2206
interface);
2207
interface = NULL;
2208
}
2209
}
2210
break;
2211
}
2212
bool interface_was_up = interface_is_up(interface);
2213
ret = bring_up_interface(interface, delay);
2214
if(not interface_was_up){
2215
if(ret != 0){
2216
errno = ret;
2217
perror_plus("Failed to bring up interface");
2218
} else {
2219
ret_errno = argz_add(&interfaces_to_take_down,
2220
&interfaces_to_take_down_size,
2221
interface);
2222
}
2223
}
2224
}
2225
if(debug and (interfaces_to_take_down == NULL)){
2226
fprintf_plus(stderr, "No interfaces were brought up\n");
2227
}
2228
}
2229
2230
/* If we only got one interface, explicitly use only that one */
2231
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2232
if(debug){
2233
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2234
mc.interfaces);
2235
}
2236
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2237
}
2238
2239
if(quit_now){
2240
goto end;
2241
}
2242
2243
ret = init_gnutls_global(pubkey, seckey, &mc);
2244
if(ret == -1){
2245
fprintf_plus(stderr, "init_gnutls_global failed\n");
2246
exitcode = EX_UNAVAILABLE;
2247
goto end;
2248
} else {
2249
gnutls_initialized = true;
2250
}
2251
2252
if(quit_now){
2253
goto end;
2254
}
2255
2256
if(mkdtemp(tempdir) == NULL){
2257
perror_plus("mkdtemp");
2258
goto end;
2259
}
2260
tempdir_created = true;
2261
2262
if(quit_now){
2263
goto end;
2264
}
2265
2266
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2267
fprintf_plus(stderr, "init_gpgme failed\n");
2268
exitcode = EX_UNAVAILABLE;
2269
goto end;
2270
} else {
2271
gpgme_initialized = true;
2272
}
2273
2274
if(quit_now){
2275
goto end;
2276
}
2277
2278
if(connect_to != NULL){
2279
/* Connect directly, do not use Zeroconf */
2280
/* (Mainly meant for debugging) */
2281
char *address = strrchr(connect_to, ':');
2282
2283
if(address == NULL){
2284
fprintf_plus(stderr, "No colon in address\n");
2285
exitcode = EX_USAGE;
2286
goto end;
2287
}
2288
2289
if(quit_now){
2290
goto end;
2291
}
2292
2293
in_port_t port;
2294
errno = 0;
2295
tmpmax = strtoimax(address+1, &tmp, 10);
2296
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2297
or tmpmax != (in_port_t)tmpmax){
2298
fprintf_plus(stderr, "Bad port number\n");
2299
exitcode = EX_USAGE;
2300
goto end;
2301
}
2302
2303
if(quit_now){
2304
goto end;
2305
}
2306
2307
port = (in_port_t)tmpmax;
2308
*address = '\0';
2309
/* Colon in address indicates IPv6 */
2310
int af;
2311
if(strchr(connect_to, ':') != NULL){
2312
af = AF_INET6;
2313
/* Accept [] around IPv6 address - see RFC 5952 */
2314
if(connect_to[0] == '[' and address[-1] == ']')
2315
{
2316
connect_to++;
2317
address[-1] = '\0';
2318
}
2319
} else {
2320
af = AF_INET;
2321
}
2322
address = connect_to;
2323
2324
if(quit_now){
2325
goto end;
2326
}
2327
2328
while(not quit_now){
2329
ret = start_mandos_communication(address, port, if_index, af,
2330
&mc);
2331
if(quit_now or ret == 0){
2332
break;
2333
}
2334
if(debug){
2335
fprintf_plus(stderr, "Retrying in %d seconds\n",
2336
(int)retry_interval);
2337
}
2338
sleep((unsigned int)retry_interval);
2339
}
2340
2341
if (not quit_now){
2342
exitcode = EXIT_SUCCESS;
2343
}
2344
2345
goto end;
2346
}
2347
2348
if(quit_now){
2349
goto end;
2350
}
2351
2352
{
2353
AvahiServerConfig config;
2354
/* Do not publish any local Zeroconf records */
2355
avahi_server_config_init(&config);
2356
config.publish_hinfo = 0;
2357
config.publish_addresses = 0;
2358
config.publish_workstation = 0;
2359
config.publish_domain = 0;
2360
2361
/* Allocate a new server */
2362
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2363
&config, NULL, NULL, &ret_errno);
2364
2365
/* Free the Avahi configuration data */
2366
avahi_server_config_free(&config);
2367
}
2368
2369
/* Check if creating the Avahi server object succeeded */
2370
if(mc.server == NULL){
2371
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2372
avahi_strerror(ret_errno));
2373
exitcode = EX_UNAVAILABLE;
2374
goto end;
2375
}
2376
2377
if(quit_now){
2378
goto end;
2379
}
2380
2381
/* Create the Avahi service browser */
2382
sb = avahi_s_service_browser_new(mc.server, if_index,
2383
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2384
NULL, 0, browse_callback,
2385
(void *)&mc);
2386
if(sb == NULL){
2387
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2388
avahi_strerror(avahi_server_errno(mc.server)));
2389
exitcode = EX_UNAVAILABLE;
2390
goto end;
2391
}
2392
2393
if(quit_now){
2394
goto end;
2395
}
2396
2397
/* Run the main loop */
2398
2399
if(debug){
2400
fprintf_plus(stderr, "Starting Avahi loop search\n");
2401
}
2402
2403
ret = avahi_loop_with_timeout(simple_poll,
2404
(int)(retry_interval * 1000), &mc);
2405
if(debug){
2406
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2407
(ret == 0) ? "successfully" : "with error");
2408
}
2409
2410
end:
2411
2412
if(debug){
2413
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2414
}
2415
2416
/* Cleanup things */
2417
free(mc.interfaces);
2418
2419
if(sb != NULL)
2420
avahi_s_service_browser_free(sb);
2421
2422
if(mc.server != NULL)
2423
avahi_server_free(mc.server);
2424
2425
if(simple_poll != NULL)
2426
avahi_simple_poll_free(simple_poll);
2427
2428
if(gnutls_initialized){
2429
gnutls_certificate_free_credentials(mc.cred);
2430
gnutls_global_deinit();
2431
gnutls_dh_params_deinit(mc.dh_params);
2432
}
2433
2434
if(gpgme_initialized){
2435
gpgme_release(mc.ctx);
2436
}
2437
2438
/* Cleans up the circular linked list of Mandos servers the client
2439
has seen */
2440
if(mc.current_server != NULL){
2441
mc.current_server->prev->next = NULL;
2442
while(mc.current_server != NULL){
2443
server *next = mc.current_server->next;
2444
free(mc.current_server);
2445
mc.current_server = next;
2446
}
2447
}
2448
2449
/* Re-raise priviliges */
2450
{
2451
raise_privileges();
2452
2453
/* Run network hooks */
2454
run_network_hooks("stop", interfaces_hooks != NULL ?
2455
interfaces_hooks : "", delay);
2456
2457
/* Take down the network interfaces which were brought up */
2458
{
2459
char *interface = NULL;
2460
while((interface=argz_next(interfaces_to_take_down,
2461
interfaces_to_take_down_size,
2462
interface))){
2463
ret_errno = take_down_interface(interface);
2464
if(ret_errno != 0){
2465
errno = ret_errno;
2466
perror_plus("Failed to take down interface");
2467
}
2468
}
2469
if(debug and (interfaces_to_take_down == NULL)){
2470
fprintf_plus(stderr, "No interfaces needed to be taken"
2471
" down\n");
2472
}
2473
}
2474
2475
lower_privileges_permanently();
2476
}
2477
2478
free(interfaces_to_take_down);
2479
free(interfaces_hooks);
2480
2481
/* Removes the GPGME temp directory and all files inside */
2482
if(tempdir_created){
2483
struct dirent **direntries = NULL;
2484
struct dirent *direntry = NULL;
2485
int numentries = scandir(tempdir, &direntries, notdotentries,
2486
alphasort);
2487
if (numentries > 0){
2488
for(int i = 0; i < numentries; i++){
2489
direntry = direntries[i];
2490
char *fullname = NULL;
2491
ret = asprintf(&fullname, "%s/%s", tempdir,
2492
direntry->d_name);
2493
if(ret < 0){
2494
perror_plus("asprintf");
2495
continue;
2496
}
2497
ret = remove(fullname);
2498
if(ret == -1){
2499
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2500
strerror(errno));
2501
}
2502
free(fullname);
2503
}
2504
}
2505
2506
/* need to clean even if 0 because man page doesn't specify */
2507
free(direntries);
2508
if (numentries == -1){
2509
perror_plus("scandir");
2510
}
2511
ret = rmdir(tempdir);
2512
if(ret == -1 and errno != ENOENT){
2513
perror_plus("rmdir");
2514
}
2515
}
2516
2517
if(quit_now){
2518
sigemptyset(&old_sigterm_action.sa_mask);
2519
old_sigterm_action.sa_handler = SIG_DFL;
2520
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2521
&old_sigterm_action,
2522
NULL));
2523
if(ret == -1){
2524
perror_plus("sigaction");
2525
}
2526
do {
2527
ret = raise(signal_received);
2528
} while(ret != 0 and errno == EINTR);
2529
if(ret != 0){
2530
perror_plus("raise");
2531
abort();
2532
}
2533
TEMP_FAILURE_RETRY(pause());
2534
}
2535
2536
return exitcode;
2537
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0