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- Committer: Teddy Hogeborn
- Date: 2008-01-18 21:23:46 UTC
- mfrom: (2.1.1 Project)
- Revision ID: teddy@fukt.bsnet.se-20080118212346-qo103d6o8r7xs4za
Merged from Björn.
- files added:
- ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- 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 © 2008-2015 Teddy Hogeborn
13
* Copyright © 2008-2015 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> /* strcmp(), strlen(), strerror(),
50
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 = 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, const))
497
static const char *safe_string(const char *str){
498
if(str == NULL)
499
return "(unknown)";
500
return str;
501
}
502
503
__attribute__((warn_unused_result))
504
static const char *safer_gnutls_strerror(int value){
505
const char *ret = gnutls_strerror(value);
506
return safe_string(ret);
507
}
508
509
/* GnuTLS log function callback */
510
__attribute__((nonnull))
511
static void debuggnutls(__attribute__((unused)) int level,
512
const char* string){
513
fprintf_plus(stderr, "GnuTLS: %s", string);
514
}
515
516
__attribute__((nonnull, warn_unused_result))
517
static int init_gnutls_global(const char *pubkeyfilename,
518
const char *seckeyfilename,
519
const char *dhparamsfilename,
520
mandos_context *mc){
521
int ret;
522
unsigned int uret;
523
524
if(debug){
525
fprintf_plus(stderr, "Initializing GnuTLS\n");
526
}
527
528
ret = gnutls_global_init();
529
if(ret != GNUTLS_E_SUCCESS){
530
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
531
safer_gnutls_strerror(ret));
532
return -1;
533
}
534
535
if(debug){
536
/* "Use a log level over 10 to enable all debugging options."
537
* - GnuTLS manual
538
*/
539
gnutls_global_set_log_level(11);
540
gnutls_global_set_log_function(debuggnutls);
541
}
542
543
/* OpenPGP credentials */
544
ret = gnutls_certificate_allocate_credentials(&mc->cred);
545
if(ret != GNUTLS_E_SUCCESS){
546
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
547
safer_gnutls_strerror(ret));
548
gnutls_global_deinit();
549
return -1;
550
}
551
552
if(debug){
553
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
554
" secret key %s as GnuTLS credentials\n",
555
pubkeyfilename,
556
seckeyfilename);
557
}
558
559
ret = gnutls_certificate_set_openpgp_key_file
560
(mc->cred, pubkeyfilename, seckeyfilename,
561
GNUTLS_OPENPGP_FMT_BASE64);
562
if(ret != GNUTLS_E_SUCCESS){
563
fprintf_plus(stderr,
564
"Error[%d] while reading the OpenPGP key pair ('%s',"
565
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
566
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
567
safer_gnutls_strerror(ret));
568
goto globalfail;
569
}
570
571
/* GnuTLS server initialization */
572
ret = gnutls_dh_params_init(&mc->dh_params);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
575
" initialization: %s\n",
576
safer_gnutls_strerror(ret));
577
goto globalfail;
578
}
579
/* If a Diffie-Hellman parameters file was given, try to use it */
580
if(dhparamsfilename != NULL){
581
gnutls_datum_t params = { .data = NULL, .size = 0 };
582
do {
583
int dhpfile = open(dhparamsfilename, O_RDONLY);
584
if(dhpfile == -1){
585
perror_plus("open");
586
dhparamsfilename = NULL;
587
break;
588
}
589
size_t params_capacity = 0;
590
while(true){
591
params_capacity = incbuffer((char **)¶ms.data,
592
(size_t)params.size,
593
(size_t)params_capacity);
594
if(params_capacity == 0){
595
perror_plus("incbuffer");
596
free(params.data);
597
params.data = NULL;
598
dhparamsfilename = NULL;
599
break;
600
}
601
ssize_t bytes_read = read(dhpfile,
602
params.data + params.size,
603
BUFFER_SIZE);
604
/* EOF */
605
if(bytes_read == 0){
606
break;
607
}
608
/* check bytes_read for failure */
609
if(bytes_read < 0){
610
perror_plus("read");
611
free(params.data);
612
params.data = NULL;
613
dhparamsfilename = NULL;
614
break;
615
}
616
params.size += (unsigned int)bytes_read;
617
}
618
if(params.data == NULL){
619
dhparamsfilename = NULL;
620
}
621
if(dhparamsfilename == NULL){
622
break;
623
}
624
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
625
GNUTLS_X509_FMT_PEM);
626
if(ret != GNUTLS_E_SUCCESS){
627
fprintf_plus(stderr, "Failed to parse DH parameters in file"
628
" \"%s\": %s\n", dhparamsfilename,
629
safer_gnutls_strerror(ret));
630
dhparamsfilename = NULL;
631
}
632
} while(false);
633
}
634
if(dhparamsfilename == NULL){
635
if(mc->dh_bits == 0){
636
/* Find out the optimal number of DH bits */
637
/* Try to read the private key file */
638
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
639
do {
640
int secfile = open(seckeyfilename, O_RDONLY);
641
if(secfile == -1){
642
perror_plus("open");
643
break;
644
}
645
size_t buffer_capacity = 0;
646
while(true){
647
buffer_capacity = incbuffer((char **)&buffer.data,
648
(size_t)buffer.size,
649
(size_t)buffer_capacity);
650
if(buffer_capacity == 0){
651
perror_plus("incbuffer");
652
free(buffer.data);
653
buffer.data = NULL;
654
break;
655
}
656
ssize_t bytes_read = read(secfile,
657
buffer.data + buffer.size,
658
BUFFER_SIZE);
659
/* EOF */
660
if(bytes_read == 0){
661
break;
662
}
663
/* check bytes_read for failure */
664
if(bytes_read < 0){
665
perror_plus("read");
666
free(buffer.data);
667
buffer.data = NULL;
668
break;
669
}
670
buffer.size += (unsigned int)bytes_read;
671
}
672
close(secfile);
673
} while(false);
674
/* If successful, use buffer to parse private key */
675
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
676
if(buffer.data != NULL){
677
{
678
gnutls_openpgp_privkey_t privkey = NULL;
679
ret = gnutls_openpgp_privkey_init(&privkey);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error initializing OpenPGP key"
682
" structure: %s",
683
safer_gnutls_strerror(ret));
684
free(buffer.data);
685
buffer.data = NULL;
686
} else {
687
ret = gnutls_openpgp_privkey_import
688
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
689
if(ret != GNUTLS_E_SUCCESS){
690
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
691
safer_gnutls_strerror(ret));
692
privkey = NULL;
693
}
694
free(buffer.data);
695
buffer.data = NULL;
696
if(privkey != NULL){
697
/* Use private key to suggest an appropriate
698
sec_param */
699
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
700
gnutls_openpgp_privkey_deinit(privkey);
701
if(debug){
702
fprintf_plus(stderr, "This OpenPGP key implies using"
703
" a GnuTLS security parameter \"%s\".\n",
704
safe_string(gnutls_sec_param_get_name
705
(sec_param)));
706
}
707
}
708
}
709
}
710
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
711
/* Err on the side of caution */
712
sec_param = GNUTLS_SEC_PARAM_ULTRA;
713
if(debug){
714
fprintf_plus(stderr, "Falling back to security parameter"
715
" \"%s\"\n",
716
safe_string(gnutls_sec_param_get_name
717
(sec_param)));
718
}
719
}
720
}
721
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
722
if(uret != 0){
723
mc->dh_bits = uret;
724
if(debug){
725
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
726
" implies %u DH bits; using that.\n",
727
safe_string(gnutls_sec_param_get_name
728
(sec_param)),
729
mc->dh_bits);
730
}
731
} else {
732
fprintf_plus(stderr, "Failed to get implied number of DH"
733
" bits for security parameter \"%s\"): %s\n",
734
safe_string(gnutls_sec_param_get_name
735
(sec_param)),
736
safer_gnutls_strerror(ret));
737
goto globalfail;
738
}
739
} else if(debug){
740
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
741
mc->dh_bits);
742
}
743
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
744
if(ret != GNUTLS_E_SUCCESS){
745
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
746
" bits): %s\n", mc->dh_bits,
747
safer_gnutls_strerror(ret));
748
goto globalfail;
749
}
750
}
751
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
752
753
return 0;
754
755
globalfail:
756
757
gnutls_certificate_free_credentials(mc->cred);
758
gnutls_global_deinit();
759
gnutls_dh_params_deinit(mc->dh_params);
760
return -1;
761
}
762
763
__attribute__((nonnull, warn_unused_result))
764
static int init_gnutls_session(gnutls_session_t *session,
765
mandos_context *mc){
766
int ret;
767
/* GnuTLS session creation */
768
do {
769
ret = gnutls_init(session, GNUTLS_SERVER);
770
if(quit_now){
771
return -1;
772
}
773
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
774
if(ret != GNUTLS_E_SUCCESS){
775
fprintf_plus(stderr,
776
"Error in GnuTLS session initialization: %s\n",
777
safer_gnutls_strerror(ret));
778
}
779
780
{
781
const char *err;
782
do {
783
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
784
if(quit_now){
785
gnutls_deinit(*session);
786
return -1;
787
}
788
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
789
if(ret != GNUTLS_E_SUCCESS){
790
fprintf_plus(stderr, "Syntax error at: %s\n", err);
791
fprintf_plus(stderr, "GnuTLS error: %s\n",
792
safer_gnutls_strerror(ret));
793
gnutls_deinit(*session);
794
return -1;
795
}
796
}
797
798
do {
799
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
800
mc->cred);
801
if(quit_now){
802
gnutls_deinit(*session);
803
return -1;
804
}
805
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
806
if(ret != GNUTLS_E_SUCCESS){
807
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
808
safer_gnutls_strerror(ret));
809
gnutls_deinit(*session);
810
return -1;
811
}
812
813
/* ignore client certificate if any. */
814
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
815
816
return 0;
817
}
818
819
/* Avahi log function callback */
820
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
821
__attribute__((unused)) const char *txt){}
822
823
/* Set effective uid to 0, return errno */
824
__attribute__((warn_unused_result))
825
error_t raise_privileges(void){
826
error_t old_errno = errno;
827
error_t ret_errno = 0;
828
if(seteuid(0) == -1){
829
ret_errno = errno;
830
}
831
errno = old_errno;
832
return ret_errno;
833
}
834
835
/* Set effective and real user ID to 0. Return errno. */
836
__attribute__((warn_unused_result))
837
error_t raise_privileges_permanently(void){
838
error_t old_errno = errno;
839
error_t ret_errno = raise_privileges();
840
if(ret_errno != 0){
841
errno = old_errno;
842
return ret_errno;
843
}
844
if(setuid(0) == -1){
845
ret_errno = errno;
846
}
847
errno = old_errno;
848
return ret_errno;
849
}
850
851
/* Set effective user ID to unprivileged saved user ID */
852
__attribute__((warn_unused_result))
853
error_t lower_privileges(void){
854
error_t old_errno = errno;
855
error_t ret_errno = 0;
856
if(seteuid(uid) == -1){
857
ret_errno = errno;
858
}
859
errno = old_errno;
860
return ret_errno;
861
}
862
863
/* Lower privileges permanently */
864
__attribute__((warn_unused_result))
865
error_t lower_privileges_permanently(void){
866
error_t old_errno = errno;
867
error_t ret_errno = 0;
868
if(setuid(uid) == -1){
869
ret_errno = errno;
870
}
871
errno = old_errno;
872
return ret_errno;
873
}
874
875
/* Helper function to add_local_route() and delete_local_route() */
876
__attribute__((nonnull, warn_unused_result))
877
static bool add_delete_local_route(const bool add,
878
const char *address,
879
AvahiIfIndex if_index){
880
int ret;
881
char helper[] = "mandos-client-iprouteadddel";
882
char add_arg[] = "add";
883
char delete_arg[] = "delete";
884
char debug_flag[] = "--debug";
885
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
886
if(pluginhelperdir == NULL){
887
if(debug){
888
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
889
" variable not set; cannot run helper\n");
890
}
891
return false;
892
}
893
894
char interface[IF_NAMESIZE];
895
if(if_indextoname((unsigned int)if_index, interface) == NULL){
896
perror_plus("if_indextoname");
897
return false;
898
}
899
900
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
901
if(devnull == -1){
902
perror_plus("open(\"/dev/null\", O_RDONLY)");
903
return false;
904
}
905
pid_t pid = fork();
906
if(pid == 0){
907
/* Child */
908
/* Raise privileges */
909
errno = raise_privileges_permanently();
910
if(errno != 0){
911
perror_plus("Failed to raise privileges");
912
/* _exit(EX_NOPERM); */
913
} else {
914
/* Set group */
915
errno = 0;
916
ret = setgid(0);
917
if(ret == -1){
918
perror_plus("setgid");
919
_exit(EX_NOPERM);
920
}
921
/* Reset supplementary groups */
922
errno = 0;
923
ret = setgroups(0, NULL);
924
if(ret == -1){
925
perror_plus("setgroups");
926
_exit(EX_NOPERM);
927
}
928
}
929
ret = dup2(devnull, STDIN_FILENO);
930
if(ret == -1){
931
perror_plus("dup2(devnull, STDIN_FILENO)");
932
_exit(EX_OSERR);
933
}
934
ret = close(devnull);
935
if(ret == -1){
936
perror_plus("close");
937
_exit(EX_OSERR);
938
}
939
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
940
if(ret == -1){
941
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
942
_exit(EX_OSERR);
943
}
944
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
945
O_RDONLY
946
| O_DIRECTORY
947
| O_PATH
948
| O_CLOEXEC));
949
if(helperdir_fd == -1){
950
perror_plus("open");
951
_exit(EX_UNAVAILABLE);
952
}
953
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
954
helper, O_RDONLY));
955
if(helper_fd == -1){
956
perror_plus("openat");
957
_exit(EX_UNAVAILABLE);
958
}
959
close(helperdir_fd);
960
#ifdef __GNUC__
961
#pragma GCC diagnostic push
962
#pragma GCC diagnostic ignored "-Wcast-qual"
963
#endif
964
if(fexecve(helper_fd, (char *const [])
965
{ helper, add ? add_arg : delete_arg, (char *)address,
966
interface, debug ? debug_flag : NULL, NULL },
967
environ) == -1){
968
#ifdef __GNUC__
969
#pragma GCC diagnostic pop
970
#endif
971
perror_plus("fexecve");
972
_exit(EXIT_FAILURE);
973
}
974
}
975
if(pid == -1){
976
perror_plus("fork");
977
return false;
978
}
979
int status;
980
pid_t pret = -1;
981
errno = 0;
982
do {
983
pret = waitpid(pid, &status, 0);
984
if(pret == -1 and errno == EINTR and quit_now){
985
int errno_raising = 0;
986
if((errno = raise_privileges()) != 0){
987
errno_raising = errno;
988
perror_plus("Failed to raise privileges in order to"
989
" kill helper program");
990
}
991
if(kill(pid, SIGTERM) == -1){
992
perror_plus("kill");
993
}
994
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
995
perror_plus("Failed to lower privileges after killing"
996
" helper program");
997
}
998
return false;
999
}
1000
} while(pret == -1 and errno == EINTR);
1001
if(pret == -1){
1002
perror_plus("waitpid");
1003
return false;
1004
}
1005
if(WIFEXITED(status)){
1006
if(WEXITSTATUS(status) != 0){
1007
fprintf_plus(stderr, "Error: iprouteadddel exited"
1008
" with status %d\n", WEXITSTATUS(status));
1009
return false;
1010
}
1011
return true;
1012
}
1013
if(WIFSIGNALED(status)){
1014
fprintf_plus(stderr, "Error: iprouteadddel died by"
1015
" signal %d\n", WTERMSIG(status));
1016
return false;
1017
}
1018
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1019
return false;
1020
}
1021
1022
__attribute__((nonnull, warn_unused_result))
1023
static bool add_local_route(const char *address,
1024
AvahiIfIndex if_index){
1025
if(debug){
1026
fprintf_plus(stderr, "Adding route to %s\n", address);
1027
}
1028
return add_delete_local_route(true, address, if_index);
1029
}
1030
1031
__attribute__((nonnull, warn_unused_result))
1032
static bool delete_local_route(const char *address,
1033
AvahiIfIndex if_index){
1034
if(debug){
1035
fprintf_plus(stderr, "Removing route to %s\n", address);
1036
}
1037
return add_delete_local_route(false, address, if_index);
1038
}
1039
1040
/* Called when a Mandos server is found */
1041
__attribute__((nonnull, warn_unused_result))
1042
static int start_mandos_communication(const char *ip, in_port_t port,
1043
AvahiIfIndex if_index,
1044
int af, mandos_context *mc){
1045
int ret, tcp_sd = -1;
1046
ssize_t sret;
1047
struct sockaddr_storage to;
1048
char *buffer = NULL;
1049
char *decrypted_buffer = NULL;
1050
size_t buffer_length = 0;
1051
size_t buffer_capacity = 0;
1052
size_t written;
1053
int retval = -1;
1054
gnutls_session_t session;
1055
int pf; /* Protocol family */
1056
bool route_added = false;
1057
1058
errno = 0;
1059
1060
if(quit_now){
1061
errno = EINTR;
1062
return -1;
1063
}
1064
1065
switch(af){
1066
case AF_INET6:
1067
pf = PF_INET6;
1068
break;
1069
case AF_INET:
1070
pf = PF_INET;
1071
break;
1072
default:
1073
fprintf_plus(stderr, "Bad address family: %d\n", af);
1074
errno = EINVAL;
1075
return -1;
1076
}
1077
1078
/* If the interface is specified and we have a list of interfaces */
1079
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1080
/* Check if the interface is one of the interfaces we are using */
1081
bool match = false;
1082
{
1083
char *interface = NULL;
1084
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1085
interface))){
1086
if(if_nametoindex(interface) == (unsigned int)if_index){
1087
match = true;
1088
break;
1089
}
1090
}
1091
}
1092
if(not match){
1093
/* This interface does not match any in the list, so we don't
1094
connect to the server */
1095
if(debug){
1096
char interface[IF_NAMESIZE];
1097
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1098
perror_plus("if_indextoname");
1099
} else {
1100
fprintf_plus(stderr, "Skipping server on non-used interface"
1101
" \"%s\"\n",
1102
if_indextoname((unsigned int)if_index,
1103
interface));
1104
}
1105
}
1106
return -1;
1107
}
1108
}
1109
1110
ret = init_gnutls_session(&session, mc);
1111
if(ret != 0){
1112
return -1;
1113
}
1114
1115
if(debug){
1116
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1117
PRIuMAX "\n", ip, (uintmax_t)port);
1118
}
1119
1120
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1121
if(tcp_sd < 0){
1122
int e = errno;
1123
perror_plus("socket");
1124
errno = e;
1125
goto mandos_end;
1126
}
1127
1128
if(quit_now){
1129
errno = EINTR;
1130
goto mandos_end;
1131
}
1132
1133
if(af == AF_INET6){
1134
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1135
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to6->sin6_addr);
1137
} else { /* IPv4 */
1138
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1139
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1140
ret = inet_pton(af, ip, &to4->sin_addr);
1141
}
1142
if(ret < 0 ){
1143
int e = errno;
1144
perror_plus("inet_pton");
1145
errno = e;
1146
goto mandos_end;
1147
}
1148
if(ret == 0){
1149
int e = errno;
1150
fprintf_plus(stderr, "Bad address: %s\n", ip);
1151
errno = e;
1152
goto mandos_end;
1153
}
1154
if(af == AF_INET6){
1155
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1156
if(IN6_IS_ADDR_LINKLOCAL
1157
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1158
if(if_index == AVAHI_IF_UNSPEC){
1159
fprintf_plus(stderr, "An IPv6 link-local address is"
1160
" incomplete without a network interface\n");
1161
errno = EINVAL;
1162
goto mandos_end;
1163
}
1164
/* Set the network interface number as scope */
1165
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1166
}
1167
} else {
1168
((struct sockaddr_in *)&to)->sin_port = htons(port);
1169
}
1170
1171
if(quit_now){
1172
errno = EINTR;
1173
goto mandos_end;
1174
}
1175
1176
if(debug){
1177
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1178
char interface[IF_NAMESIZE];
1179
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1180
perror_plus("if_indextoname");
1181
} else {
1182
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1183
"\n", ip, interface, (uintmax_t)port);
1184
}
1185
} else {
1186
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1187
ip, (uintmax_t)port);
1188
}
1189
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1190
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1191
if(af == AF_INET6){
1192
ret = getnameinfo((struct sockaddr *)&to,
1193
sizeof(struct sockaddr_in6),
1194
addrstr, sizeof(addrstr), NULL, 0,
1195
NI_NUMERICHOST);
1196
} else {
1197
ret = getnameinfo((struct sockaddr *)&to,
1198
sizeof(struct sockaddr_in),
1199
addrstr, sizeof(addrstr), NULL, 0,
1200
NI_NUMERICHOST);
1201
}
1202
if(ret == EAI_SYSTEM){
1203
perror_plus("getnameinfo");
1204
} else if(ret != 0) {
1205
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1206
} else if(strcmp(addrstr, ip) != 0){
1207
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1208
}
1209
}
1210
1211
if(quit_now){
1212
errno = EINTR;
1213
goto mandos_end;
1214
}
1215
1216
while(true){
1217
if(af == AF_INET6){
1218
ret = connect(tcp_sd, (struct sockaddr *)&to,
1219
sizeof(struct sockaddr_in6));
1220
} else {
1221
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1222
sizeof(struct sockaddr_in));
1223
}
1224
if(ret < 0){
1225
if(errno == ENETUNREACH
1226
and if_index != AVAHI_IF_UNSPEC
1227
and connect_to == NULL
1228
and not route_added and
1229
((af == AF_INET6 and not
1230
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1231
&to)->sin6_addr)))
1232
or (af == AF_INET and
1233
/* Not a a IPv4LL address */
1234
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1235
& 0xFFFF0000L) != 0xA9FE0000L))){
1236
/* Work around Avahi bug - Avahi does not announce link-local
1237
addresses if it has a global address, so local hosts with
1238
*only* a link-local address (e.g. Mandos clients) cannot
1239
connect to a Mandos server announced by Avahi on a server
1240
host with a global address. Work around this by retrying
1241
with an explicit route added with the server's address.
1242
1243
Avahi bug reference:
1244
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1245
https://bugs.debian.org/587961
1246
*/
1247
if(debug){
1248
fprintf_plus(stderr, "Mandos server unreachable, trying"
1249
" direct route\n");
1250
}
1251
int e = errno;
1252
route_added = add_local_route(ip, if_index);
1253
if(route_added){
1254
continue;
1255
}
1256
errno = e;
1257
}
1258
if(errno != ECONNREFUSED or debug){
1259
int e = errno;
1260
perror_plus("connect");
1261
errno = e;
1262
}
1263
goto mandos_end;
1264
}
1265
1266
if(quit_now){
1267
errno = EINTR;
1268
goto mandos_end;
1269
}
1270
break;
1271
}
1272
1273
const char *out = mandos_protocol_version;
1274
written = 0;
1275
while(true){
1276
size_t out_size = strlen(out);
1277
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1278
out_size - written));
1279
if(ret == -1){
1280
int e = errno;
1281
perror_plus("write");
1282
errno = e;
1283
goto mandos_end;
1284
}
1285
written += (size_t)ret;
1286
if(written < out_size){
1287
continue;
1288
} else {
1289
if(out == mandos_protocol_version){
1290
written = 0;
1291
out = "\r\n";
1292
} else {
1293
break;
1294
}
1295
}
1296
1297
if(quit_now){
1298
errno = EINTR;
1299
goto mandos_end;
1300
}
1301
}
1302
1303
if(debug){
1304
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1305
}
1306
1307
if(quit_now){
1308
errno = EINTR;
1309
goto mandos_end;
1310
}
1311
1312
/* This casting via intptr_t is to eliminate warning about casting
1313
an int to a pointer type. This is exactly how the GnuTLS Guile
1314
function "set-session-transport-fd!" does it. */
1315
gnutls_transport_set_ptr(session,
1316
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1317
1318
if(quit_now){
1319
errno = EINTR;
1320
goto mandos_end;
1321
}
1322
1323
do {
1324
ret = gnutls_handshake(session);
1325
if(quit_now){
1326
errno = EINTR;
1327
goto mandos_end;
1328
}
1329
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1330
1331
if(ret != GNUTLS_E_SUCCESS){
1332
if(debug){
1333
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
1334
gnutls_perror(ret);
1335
}
1336
errno = EPROTO;
1337
goto mandos_end;
1338
}
1339
1340
/* Read OpenPGP packet that contains the wanted password */
1341
1342
if(debug){
1343
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1344
" %s\n", ip);
1345
}
1346
1347
while(true){
1348
1349
if(quit_now){
1350
errno = EINTR;
1351
goto mandos_end;
1352
}
1353
1354
buffer_capacity = incbuffer(&buffer, buffer_length,
1355
buffer_capacity);
1356
if(buffer_capacity == 0){
1357
int e = errno;
1358
perror_plus("incbuffer");
1359
errno = e;
1360
goto mandos_end;
1361
}
1362
1363
if(quit_now){
1364
errno = EINTR;
1365
goto mandos_end;
1366
}
1367
1368
sret = gnutls_record_recv(session, buffer+buffer_length,
1369
BUFFER_SIZE);
1370
if(sret == 0){
1371
break;
1372
}
1373
if(sret < 0){
1374
switch(sret){
1375
case GNUTLS_E_INTERRUPTED:
1376
case GNUTLS_E_AGAIN:
1377
break;
1378
case GNUTLS_E_REHANDSHAKE:
1379
do {
1380
ret = gnutls_handshake(session);
1381
1382
if(quit_now){
1383
errno = EINTR;
1384
goto mandos_end;
1385
}
1386
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1387
if(ret < 0){
1388
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1389
"***\n");
1390
gnutls_perror(ret);
1391
errno = EPROTO;
1392
goto mandos_end;
1393
}
1394
break;
1395
default:
1396
fprintf_plus(stderr, "Unknown error while reading data from"
1397
" encrypted session with Mandos server\n");
1398
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1399
errno = EIO;
1400
goto mandos_end;
1401
}
1402
} else {
1403
buffer_length += (size_t) sret;
1404
}
1405
}
1406
1407
if(debug){
1408
fprintf_plus(stderr, "Closing TLS session\n");
1409
}
1410
1411
if(quit_now){
1412
errno = EINTR;
1413
goto mandos_end;
1414
}
1415
1416
do {
1417
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1418
if(quit_now){
1419
errno = EINTR;
1420
goto mandos_end;
1421
}
1422
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1423
1424
if(buffer_length > 0){
1425
ssize_t decrypted_buffer_size;
1426
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1427
&decrypted_buffer, mc);
1428
if(decrypted_buffer_size >= 0){
1429
1430
written = 0;
1431
while(written < (size_t) decrypted_buffer_size){
1432
if(quit_now){
1433
errno = EINTR;
1434
goto mandos_end;
1435
}
1436
1437
ret = (int)fwrite(decrypted_buffer + written, 1,
1438
(size_t)decrypted_buffer_size - written,
1439
stdout);
1440
if(ret == 0 and ferror(stdout)){
1441
int e = errno;
1442
if(debug){
1443
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1444
strerror(errno));
1445
}
1446
errno = e;
1447
goto mandos_end;
1448
}
1449
written += (size_t)ret;
1450
}
1451
retval = 0;
1452
}
1453
}
1454
1455
/* Shutdown procedure */
1456
1457
mandos_end:
1458
{
1459
if(route_added){
1460
if(not delete_local_route(ip, if_index)){
1461
fprintf_plus(stderr, "Failed to delete local route to %s on"
1462
" interface %d", ip, if_index);
1463
}
1464
}
1465
int e = errno;
1466
free(decrypted_buffer);
1467
free(buffer);
1468
if(tcp_sd >= 0){
1469
ret = close(tcp_sd);
1470
}
1471
if(ret == -1){
1472
if(e == 0){
1473
e = errno;
1474
}
1475
perror_plus("close");
1476
}
1477
gnutls_deinit(session);
1478
errno = e;
1479
if(quit_now){
1480
errno = EINTR;
1481
retval = -1;
1482
}
1483
}
1484
return retval;
1485
}
1486
1487
__attribute__((nonnull))
1488
static void resolve_callback(AvahiSServiceResolver *r,
1489
AvahiIfIndex interface,
1490
AvahiProtocol proto,
1491
AvahiResolverEvent event,
1492
const char *name,
1493
const char *type,
1494
const char *domain,
1495
const char *host_name,
1496
const AvahiAddress *address,
1497
uint16_t port,
1498
AVAHI_GCC_UNUSED AvahiStringList *txt,
1499
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1500
flags,
1501
void *mc){
1502
if(r == NULL){
1503
return;
1504
}
1505
1506
/* Called whenever a service has been resolved successfully or
1507
timed out */
1508
1509
if(quit_now){
1510
avahi_s_service_resolver_free(r);
1511
return;
1512
}
1513
1514
switch(event){
1515
default:
1516
case AVAHI_RESOLVER_FAILURE:
1517
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1518
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1519
domain,
1520
avahi_strerror(avahi_server_errno
1521
(((mandos_context*)mc)->server)));
1522
break;
1523
1524
case AVAHI_RESOLVER_FOUND:
1525
{
1526
char ip[AVAHI_ADDRESS_STR_MAX];
1527
avahi_address_snprint(ip, sizeof(ip), address);
1528
if(debug){
1529
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1530
PRIdMAX ") on port %" PRIu16 "\n", name,
1531
host_name, ip, (intmax_t)interface, port);
1532
}
1533
int ret = start_mandos_communication(ip, (in_port_t)port,
1534
interface,
1535
avahi_proto_to_af(proto),
1536
mc);
1537
if(ret == 0){
1538
avahi_simple_poll_quit(simple_poll);
1539
} else {
1540
if(not add_server(ip, (in_port_t)port, interface,
1541
avahi_proto_to_af(proto),
1542
&((mandos_context*)mc)->current_server)){
1543
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1544
" list\n", name);
1545
}
1546
}
1547
}
1548
}
1549
avahi_s_service_resolver_free(r);
1550
}
1551
1552
static void browse_callback(AvahiSServiceBrowser *b,
1553
AvahiIfIndex interface,
1554
AvahiProtocol protocol,
1555
AvahiBrowserEvent event,
1556
const char *name,
1557
const char *type,
1558
const char *domain,
1559
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1560
flags,
1561
void *mc){
1562
if(b == NULL){
1563
return;
1564
}
1565
1566
/* Called whenever a new services becomes available on the LAN or
1567
is removed from the LAN */
1568
1569
if(quit_now){
1570
return;
1571
}
1572
1573
switch(event){
1574
default:
1575
case AVAHI_BROWSER_FAILURE:
1576
1577
fprintf_plus(stderr, "(Avahi browser) %s\n",
1578
avahi_strerror(avahi_server_errno
1579
(((mandos_context*)mc)->server)));
1580
avahi_simple_poll_quit(simple_poll);
1581
return;
1582
1583
case AVAHI_BROWSER_NEW:
1584
/* We ignore the returned Avahi resolver object. In the callback
1585
function we free it. If the Avahi server is terminated before
1586
the callback function is called the Avahi server will free the
1587
resolver for us. */
1588
1589
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1590
interface, protocol, name, type,
1591
domain, protocol, 0,
1592
resolve_callback, mc) == NULL)
1593
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1594
" %s\n", name,
1595
avahi_strerror(avahi_server_errno
1596
(((mandos_context*)mc)->server)));
1597
break;
1598
1599
case AVAHI_BROWSER_REMOVE:
1600
break;
1601
1602
case AVAHI_BROWSER_ALL_FOR_NOW:
1603
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1604
if(debug){
1605
fprintf_plus(stderr, "No Mandos server found, still"
1606
" searching...\n");
1607
}
1608
break;
1609
}
1610
}
1611
1612
/* Signal handler that stops main loop after SIGTERM */
1613
static void handle_sigterm(int sig){
1614
if(quit_now){
1615
return;
1616
}
1617
quit_now = 1;
1618
signal_received = sig;
1619
int old_errno = errno;
1620
/* set main loop to exit */
1621
if(simple_poll != NULL){
1622
avahi_simple_poll_quit(simple_poll);
1623
}
1624
errno = old_errno;
1625
}
1626
1627
__attribute__((nonnull, warn_unused_result))
1628
bool get_flags(const char *ifname, struct ifreq *ifr){
1629
int ret;
1630
error_t ret_errno;
1631
1632
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1633
if(s < 0){
1634
ret_errno = errno;
1635
perror_plus("socket");
1636
errno = ret_errno;
1637
return false;
1638
}
1639
strcpy(ifr->ifr_name, ifname);
1640
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1641
if(ret == -1){
1642
if(debug){
1643
ret_errno = errno;
1644
perror_plus("ioctl SIOCGIFFLAGS");
1645
errno = ret_errno;
1646
}
1647
return false;
1648
}
1649
return true;
1650
}
1651
1652
__attribute__((nonnull, warn_unused_result))
1653
bool good_flags(const char *ifname, const struct ifreq *ifr){
1654
1655
/* Reject the loopback device */
1656
if(ifr->ifr_flags & IFF_LOOPBACK){
1657
if(debug){
1658
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1659
ifname);
1660
}
1661
return false;
1662
}
1663
/* Accept point-to-point devices only if connect_to is specified */
1664
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1665
if(debug){
1666
fprintf_plus(stderr, "Accepting point-to-point interface"
1667
" \"%s\"\n", ifname);
1668
}
1669
return true;
1670
}
1671
/* Otherwise, reject non-broadcast-capable devices */
1672
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1673
if(debug){
1674
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1675
" \"%s\"\n", ifname);
1676
}
1677
return false;
1678
}
1679
/* Reject non-ARP interfaces (including dummy interfaces) */
1680
if(ifr->ifr_flags & IFF_NOARP){
1681
if(debug){
1682
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1683
ifname);
1684
}
1685
return false;
1686
}
1687
1688
/* Accept this device */
1689
if(debug){
1690
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1691
}
1692
return true;
1693
}
1694
1695
/*
1696
* This function determines if a directory entry in /sys/class/net
1697
* corresponds to an acceptable network device.
1698
* (This function is passed to scandir(3) as a filter function.)
1699
*/
1700
__attribute__((nonnull, warn_unused_result))
1701
int good_interface(const struct dirent *if_entry){
1702
if(if_entry->d_name[0] == '.'){
1703
return 0;
1704
}
1705
1706
struct ifreq ifr;
1707
if(not get_flags(if_entry->d_name, &ifr)){
1708
if(debug){
1709
fprintf_plus(stderr, "Failed to get flags for interface "
1710
"\"%s\"\n", if_entry->d_name);
1711
}
1712
return 0;
1713
}
1714
1715
if(not good_flags(if_entry->d_name, &ifr)){
1716
return 0;
1717
}
1718
return 1;
1719
}
1720
1721
/*
1722
* This function determines if a network interface is up.
1723
*/
1724
__attribute__((nonnull, warn_unused_result))
1725
bool interface_is_up(const char *interface){
1726
struct ifreq ifr;
1727
if(not get_flags(interface, &ifr)){
1728
if(debug){
1729
fprintf_plus(stderr, "Failed to get flags for interface "
1730
"\"%s\"\n", interface);
1731
}
1732
return false;
1733
}
1734
1735
return (bool)(ifr.ifr_flags & IFF_UP);
1736
}
1737
1738
/*
1739
* This function determines if a network interface is running
1740
*/
1741
__attribute__((nonnull, warn_unused_result))
1742
bool interface_is_running(const char *interface){
1743
struct ifreq ifr;
1744
if(not get_flags(interface, &ifr)){
1745
if(debug){
1746
fprintf_plus(stderr, "Failed to get flags for interface "
1747
"\"%s\"\n", interface);
1748
}
1749
return false;
1750
}
1751
1752
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1753
}
1754
1755
__attribute__((nonnull, pure, warn_unused_result))
1756
int notdotentries(const struct dirent *direntry){
1757
/* Skip "." and ".." */
1758
if(direntry->d_name[0] == '.'
1759
and (direntry->d_name[1] == '\0'
1760
or (direntry->d_name[1] == '.'
1761
and direntry->d_name[2] == '\0'))){
1762
return 0;
1763
}
1764
return 1;
1765
}
1766
1767
/* Is this directory entry a runnable program? */
1768
__attribute__((nonnull, warn_unused_result))
1769
int runnable_hook(const struct dirent *direntry){
1770
int ret;
1771
size_t sret;
1772
struct stat st;
1773
1774
if((direntry->d_name)[0] == '\0'){
1775
/* Empty name? */
1776
return 0;
1777
}
1778
1779
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1780
"abcdefghijklmnopqrstuvwxyz"
1781
"0123456789"
1782
"_.-");
1783
if((direntry->d_name)[sret] != '\0'){
1784
/* Contains non-allowed characters */
1785
if(debug){
1786
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1787
direntry->d_name);
1788
}
1789
return 0;
1790
}
1791
1792
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1793
if(ret == -1){
1794
if(debug){
1795
perror_plus("Could not stat hook");
1796
}
1797
return 0;
1798
}
1799
if(not (S_ISREG(st.st_mode))){
1800
/* Not a regular file */
1801
if(debug){
1802
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1803
direntry->d_name);
1804
}
1805
return 0;
1806
}
1807
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1808
/* Not executable */
1809
if(debug){
1810
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1811
direntry->d_name);
1812
}
1813
return 0;
1814
}
1815
if(debug){
1816
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1817
direntry->d_name);
1818
}
1819
return 1;
1820
}
1821
1822
__attribute__((nonnull, warn_unused_result))
1823
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1824
mandos_context *mc){
1825
int ret;
1826
struct timespec now;
1827
struct timespec waited_time;
1828
intmax_t block_time;
1829
1830
while(true){
1831
if(mc->current_server == NULL){
1832
if(debug){
1833
fprintf_plus(stderr, "Wait until first server is found."
1834
" No timeout!\n");
1835
}
1836
ret = avahi_simple_poll_iterate(s, -1);
1837
} else {
1838
if(debug){
1839
fprintf_plus(stderr, "Check current_server if we should run"
1840
" it, or wait\n");
1841
}
1842
/* the current time */
1843
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1844
if(ret == -1){
1845
perror_plus("clock_gettime");
1846
return -1;
1847
}
1848
/* Calculating in ms how long time between now and server
1849
who we visted longest time ago. Now - last seen. */
1850
waited_time.tv_sec = (now.tv_sec
1851
- mc->current_server->last_seen.tv_sec);
1852
waited_time.tv_nsec = (now.tv_nsec
1853
- mc->current_server->last_seen.tv_nsec);
1854
/* total time is 10s/10,000ms.
1855
Converting to s from ms by dividing by 1,000,
1856
and ns to ms by dividing by 1,000,000. */
1857
block_time = ((retry_interval
1858
- ((intmax_t)waited_time.tv_sec * 1000))
1859
- ((intmax_t)waited_time.tv_nsec / 1000000));
1860
1861
if(debug){
1862
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1863
block_time);
1864
}
1865
1866
if(block_time <= 0){
1867
ret = start_mandos_communication(mc->current_server->ip,
1868
mc->current_server->port,
1869
mc->current_server->if_index,
1870
mc->current_server->af, mc);
1871
if(ret == 0){
1872
avahi_simple_poll_quit(s);
1873
return 0;
1874
}
1875
ret = clock_gettime(CLOCK_MONOTONIC,
1876
&mc->current_server->last_seen);
1877
if(ret == -1){
1878
perror_plus("clock_gettime");
1879
return -1;
1880
}
1881
mc->current_server = mc->current_server->next;
1882
block_time = 0; /* Call avahi to find new Mandos
1883
servers, but don't block */
1884
}
1885
1886
ret = avahi_simple_poll_iterate(s, (int)block_time);
1887
}
1888
if(ret != 0){
1889
if(ret > 0 or errno != EINTR){
1890
return (ret != 1) ? ret : 0;
1891
}
1892
}
1893
}
1894
}
1895
1896
__attribute__((nonnull))
1897
void run_network_hooks(const char *mode, const char *interface,
1898
const float delay){
1899
struct dirent **direntries = NULL;
1900
if(hookdir_fd == -1){
1901
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1902
| O_CLOEXEC);
1903
if(hookdir_fd == -1){
1904
if(errno == ENOENT){
1905
if(debug){
1906
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1907
" found\n", hookdir);
1908
}
1909
} else {
1910
perror_plus("open");
1911
}
1912
return;
1913
}
1914
}
1915
#ifdef __GLIBC__
1916
#if __GLIBC_PREREQ(2, 15)
1917
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1918
runnable_hook, alphasort);
1919
#else /* not __GLIBC_PREREQ(2, 15) */
1920
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1921
alphasort);
1922
#endif /* not __GLIBC_PREREQ(2, 15) */
1923
#else /* not __GLIBC__ */
1924
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1925
alphasort);
1926
#endif /* not __GLIBC__ */
1927
if(numhooks == -1){
1928
perror_plus("scandir");
1929
return;
1930
}
1931
struct dirent *direntry;
1932
int ret;
1933
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1934
if(devnull == -1){
1935
perror_plus("open(\"/dev/null\", O_RDONLY)");
1936
return;
1937
}
1938
for(int i = 0; i < numhooks; i++){
1939
direntry = direntries[i];
1940
if(debug){
1941
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1942
direntry->d_name);
1943
}
1944
pid_t hook_pid = fork();
1945
if(hook_pid == 0){
1946
/* Child */
1947
/* Raise privileges */
1948
errno = raise_privileges_permanently();
1949
if(errno != 0){
1950
perror_plus("Failed to raise privileges");
1951
_exit(EX_NOPERM);
1952
}
1953
/* Set group */
1954
errno = 0;
1955
ret = setgid(0);
1956
if(ret == -1){
1957
perror_plus("setgid");
1958
_exit(EX_NOPERM);
1959
}
1960
/* Reset supplementary groups */
1961
errno = 0;
1962
ret = setgroups(0, NULL);
1963
if(ret == -1){
1964
perror_plus("setgroups");
1965
_exit(EX_NOPERM);
1966
}
1967
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1968
if(ret == -1){
1969
perror_plus("setenv");
1970
_exit(EX_OSERR);
1971
}
1972
ret = setenv("DEVICE", interface, 1);
1973
if(ret == -1){
1974
perror_plus("setenv");
1975
_exit(EX_OSERR);
1976
}
1977
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1978
if(ret == -1){
1979
perror_plus("setenv");
1980
_exit(EX_OSERR);
1981
}
1982
ret = setenv("MODE", mode, 1);
1983
if(ret == -1){
1984
perror_plus("setenv");
1985
_exit(EX_OSERR);
1986
}
1987
char *delaystring;
1988
ret = asprintf(&delaystring, "%f", (double)delay);
1989
if(ret == -1){
1990
perror_plus("asprintf");
1991
_exit(EX_OSERR);
1992
}
1993
ret = setenv("DELAY", delaystring, 1);
1994
if(ret == -1){
1995
free(delaystring);
1996
perror_plus("setenv");
1997
_exit(EX_OSERR);
1998
}
1999
free(delaystring);
2000
if(connect_to != NULL){
2001
ret = setenv("CONNECT", connect_to, 1);
2002
if(ret == -1){
2003
perror_plus("setenv");
2004
_exit(EX_OSERR);
2005
}
2006
}
2007
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2008
direntry->d_name,
2009
O_RDONLY));
2010
if(hook_fd == -1){
2011
perror_plus("openat");
2012
_exit(EXIT_FAILURE);
2013
}
2014
if(close(hookdir_fd) == -1){
2015
perror_plus("close");
2016
_exit(EXIT_FAILURE);
2017
}
2018
ret = dup2(devnull, STDIN_FILENO);
2019
if(ret == -1){
2020
perror_plus("dup2(devnull, STDIN_FILENO)");
2021
_exit(EX_OSERR);
2022
}
2023
ret = close(devnull);
2024
if(ret == -1){
2025
perror_plus("close");
2026
_exit(EX_OSERR);
2027
}
2028
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2029
if(ret == -1){
2030
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2031
_exit(EX_OSERR);
2032
}
2033
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2034
environ) == -1){
2035
perror_plus("fexecve");
2036
_exit(EXIT_FAILURE);
2037
}
2038
} else {
2039
if(hook_pid == -1){
2040
perror_plus("fork");
2041
free(direntry);
2042
continue;
2043
}
2044
int status;
2045
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2046
perror_plus("waitpid");
2047
free(direntry);
2048
continue;
2049
}
2050
if(WIFEXITED(status)){
2051
if(WEXITSTATUS(status) != 0){
2052
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2053
" with status %d\n", direntry->d_name,
2054
WEXITSTATUS(status));
2055
free(direntry);
2056
continue;
2057
}
2058
} else if(WIFSIGNALED(status)){
2059
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2060
" signal %d\n", direntry->d_name,
2061
WTERMSIG(status));
2062
free(direntry);
2063
continue;
2064
} else {
2065
fprintf_plus(stderr, "Warning: network hook \"%s\""
2066
" crashed\n", direntry->d_name);
2067
free(direntry);
2068
continue;
2069
}
2070
}
2071
if(debug){
2072
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2073
direntry->d_name);
2074
}
2075
free(direntry);
2076
}
2077
free(direntries);
2078
if(close(hookdir_fd) == -1){
2079
perror_plus("close");
2080
} else {
2081
hookdir_fd = -1;
2082
}
2083
close(devnull);
2084
}
2085
2086
__attribute__((nonnull, warn_unused_result))
2087
error_t bring_up_interface(const char *const interface,
2088
const float delay){
2089
error_t old_errno = errno;
2090
int ret;
2091
struct ifreq network;
2092
unsigned int if_index = if_nametoindex(interface);
2093
if(if_index == 0){
2094
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2095
errno = old_errno;
2096
return ENXIO;
2097
}
2098
2099
if(quit_now){
2100
errno = old_errno;
2101
return EINTR;
2102
}
2103
2104
if(not interface_is_up(interface)){
2105
error_t ret_errno = 0, ioctl_errno = 0;
2106
if(not get_flags(interface, &network)){
2107
ret_errno = errno;
2108
fprintf_plus(stderr, "Failed to get flags for interface "
2109
"\"%s\"\n", interface);
2110
errno = old_errno;
2111
return ret_errno;
2112
}
2113
network.ifr_flags |= IFF_UP; /* set flag */
2114
2115
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2116
if(sd == -1){
2117
ret_errno = errno;
2118
perror_plus("socket");
2119
errno = old_errno;
2120
return ret_errno;
2121
}
2122
2123
if(quit_now){
2124
ret = close(sd);
2125
if(ret == -1){
2126
perror_plus("close");
2127
}
2128
errno = old_errno;
2129
return EINTR;
2130
}
2131
2132
if(debug){
2133
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2134
interface);
2135
}
2136
2137
/* Raise privileges */
2138
ret_errno = raise_privileges();
2139
if(ret_errno != 0){
2140
errno = ret_errno;
2141
perror_plus("Failed to raise privileges");
2142
}
2143
2144
#ifdef __linux__
2145
int ret_linux;
2146
bool restore_loglevel = false;
2147
if(ret_errno == 0){
2148
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2149
messages about the network interface to mess up the prompt */
2150
ret_linux = klogctl(8, NULL, 5);
2151
if(ret_linux == -1){
2152
perror_plus("klogctl");
2153
} else {
2154
restore_loglevel = true;
2155
}
2156
}
2157
#endif /* __linux__ */
2158
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2159
ioctl_errno = errno;
2160
#ifdef __linux__
2161
if(restore_loglevel){
2162
ret_linux = klogctl(7, NULL, 0);
2163
if(ret_linux == -1){
2164
perror_plus("klogctl");
2165
}
2166
}
2167
#endif /* __linux__ */
2168
2169
/* If raise_privileges() succeeded above */
2170
if(ret_errno == 0){
2171
/* Lower privileges */
2172
ret_errno = lower_privileges();
2173
if(ret_errno != 0){
2174
errno = ret_errno;
2175
perror_plus("Failed to lower privileges");
2176
}
2177
}
2178
2179
/* Close the socket */
2180
ret = close(sd);
2181
if(ret == -1){
2182
perror_plus("close");
2183
}
2184
2185
if(ret_setflags == -1){
2186
errno = ioctl_errno;
2187
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2188
errno = old_errno;
2189
return ioctl_errno;
2190
}
2191
} else if(debug){
2192
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2193
interface);
2194
}
2195
2196
/* Sleep checking until interface is running.
2197
Check every 0.25s, up to total time of delay */
2198
for(int i=0; i < delay * 4; i++){
2199
if(interface_is_running(interface)){
2200
break;
2201
}
2202
struct timespec sleeptime = { .tv_nsec = 250000000 };
2203
ret = nanosleep(&sleeptime, NULL);
2204
if(ret == -1 and errno != EINTR){
2205
perror_plus("nanosleep");
2206
}
2207
}
2208
2209
errno = old_errno;
2210
return 0;
2211
}
2212
2213
__attribute__((nonnull, warn_unused_result))
2214
error_t take_down_interface(const char *const interface){
2215
error_t old_errno = errno;
2216
struct ifreq network;
2217
unsigned int if_index = if_nametoindex(interface);
2218
if(if_index == 0){
2219
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2220
errno = old_errno;
2221
return ENXIO;
2222
}
2223
if(interface_is_up(interface)){
2224
error_t ret_errno = 0, ioctl_errno = 0;
2225
if(not get_flags(interface, &network) and debug){
2226
ret_errno = errno;
2227
fprintf_plus(stderr, "Failed to get flags for interface "
2228
"\"%s\"\n", interface);
2229
errno = old_errno;
2230
return ret_errno;
2231
}
2232
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2233
2234
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2235
if(sd == -1){
2236
ret_errno = errno;
2237
perror_plus("socket");
2238
errno = old_errno;
2239
return ret_errno;
2240
}
2241
2242
if(debug){
2243
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2244
interface);
2245
}
2246
2247
/* Raise privileges */
2248
ret_errno = raise_privileges();
2249
if(ret_errno != 0){
2250
errno = ret_errno;
2251
perror_plus("Failed to raise privileges");
2252
}
2253
2254
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2255
ioctl_errno = errno;
2256
2257
/* If raise_privileges() succeeded above */
2258
if(ret_errno == 0){
2259
/* Lower privileges */
2260
ret_errno = lower_privileges();
2261
if(ret_errno != 0){
2262
errno = ret_errno;
2263
perror_plus("Failed to lower privileges");
2264
}
2265
}
2266
2267
/* Close the socket */
2268
int ret = close(sd);
2269
if(ret == -1){
2270
perror_plus("close");
2271
}
2272
2273
if(ret_setflags == -1){
2274
errno = ioctl_errno;
2275
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2276
errno = old_errno;
2277
return ioctl_errno;
2278
}
2279
} else if(debug){
2280
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2281
interface);
2282
}
2283
2284
errno = old_errno;
2285
return 0;
2286
}
2287
2288
int main(int argc, char *argv[]){
2289
mandos_context mc = { .server = NULL, .dh_bits = 0,
2290
.priority = "SECURE256:!CTYPE-X.509:"
2291
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
2292
.interfaces = NULL, .interfaces_size = 0 };
2293
AvahiSServiceBrowser *sb = NULL;
2294
error_t ret_errno;
2295
int ret;
2296
intmax_t tmpmax;
2297
char *tmp;
2298
int exitcode = EXIT_SUCCESS;
2299
char *interfaces_to_take_down = NULL;
2300
size_t interfaces_to_take_down_size = 0;
2301
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2302
char old_tempdir[] = "/tmp/mandosXXXXXX";
2303
char *tempdir = NULL;
2304
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2305
const char *seckey = PATHDIR "/" SECKEY;
2306
const char *pubkey = PATHDIR "/" PUBKEY;
2307
const char *dh_params_file = NULL;
2308
char *interfaces_hooks = NULL;
2309
2310
bool gnutls_initialized = false;
2311
bool gpgme_initialized = false;
2312
float delay = 2.5f;
2313
double retry_interval = 10; /* 10s between trying a server and
2314
retrying the same server again */
2315
2316
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2317
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2318
2319
uid = getuid();
2320
gid = getgid();
2321
2322
/* Lower any group privileges we might have, just to be safe */
2323
errno = 0;
2324
ret = setgid(gid);
2325
if(ret == -1){
2326
perror_plus("setgid");
2327
}
2328
2329
/* Lower user privileges (temporarily) */
2330
errno = 0;
2331
ret = seteuid(uid);
2332
if(ret == -1){
2333
perror_plus("seteuid");
2334
}
2335
2336
if(quit_now){
2337
goto end;
2338
}
2339
2340
{
2341
struct argp_option options[] = {
2342
{ .name = "debug", .key = 128,
2343
.doc = "Debug mode", .group = 3 },
2344
{ .name = "connect", .key = 'c',
2345
.arg = "ADDRESS:PORT",
2346
.doc = "Connect directly to a specific Mandos server",
2347
.group = 1 },
2348
{ .name = "interface", .key = 'i',
2349
.arg = "NAME",
2350
.doc = "Network interface that will be used to search for"
2351
" Mandos servers",
2352
.group = 1 },
2353
{ .name = "seckey", .key = 's',
2354
.arg = "FILE",
2355
.doc = "OpenPGP secret key file base name",
2356
.group = 1 },
2357
{ .name = "pubkey", .key = 'p',
2358
.arg = "FILE",
2359
.doc = "OpenPGP public key file base name",
2360
.group = 2 },
2361
{ .name = "dh-bits", .key = 129,
2362
.arg = "BITS",
2363
.doc = "Bit length of the prime number used in the"
2364
" Diffie-Hellman key exchange",
2365
.group = 2 },
2366
{ .name = "dh-params", .key = 134,
2367
.arg = "FILE",
2368
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2369
" for the Diffie-Hellman key exchange",
2370
.group = 2 },
2371
{ .name = "priority", .key = 130,
2372
.arg = "STRING",
2373
.doc = "GnuTLS priority string for the TLS handshake",
2374
.group = 1 },
2375
{ .name = "delay", .key = 131,
2376
.arg = "SECONDS",
2377
.doc = "Maximum delay to wait for interface startup",
2378
.group = 2 },
2379
{ .name = "retry", .key = 132,
2380
.arg = "SECONDS",
2381
.doc = "Retry interval used when denied by the Mandos server",
2382
.group = 2 },
2383
{ .name = "network-hook-dir", .key = 133,
2384
.arg = "DIR",
2385
.doc = "Directory where network hooks are located",
2386
.group = 2 },
2387
/*
2388
* These reproduce what we would get without ARGP_NO_HELP
2389
*/
2390
{ .name = "help", .key = '?',
2391
.doc = "Give this help list", .group = -1 },
2392
{ .name = "usage", .key = -3,
2393
.doc = "Give a short usage message", .group = -1 },
2394
{ .name = "version", .key = 'V',
2395
.doc = "Print program version", .group = -1 },
2396
{ .name = NULL }
2397
};
2398
2399
error_t parse_opt(int key, char *arg,
2400
struct argp_state *state){
2401
errno = 0;
2402
switch(key){
2403
case 128: /* --debug */
2404
debug = true;
2405
break;
2406
case 'c': /* --connect */
2407
connect_to = arg;
2408
break;
2409
case 'i': /* --interface */
2410
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2411
arg, (int)',');
2412
if(ret_errno != 0){
2413
argp_error(state, "%s", strerror(ret_errno));
2414
}
2415
break;
2416
case 's': /* --seckey */
2417
seckey = arg;
2418
break;
2419
case 'p': /* --pubkey */
2420
pubkey = arg;
2421
break;
2422
case 129: /* --dh-bits */
2423
errno = 0;
2424
tmpmax = strtoimax(arg, &tmp, 10);
2425
if(errno != 0 or tmp == arg or *tmp != '\0'
2426
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2427
argp_error(state, "Bad number of DH bits");
2428
}
2429
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2430
break;
2431
case 134: /* --dh-params */
2432
dh_params_file = arg;
2433
break;
2434
case 130: /* --priority */
2435
mc.priority = arg;
2436
break;
2437
case 131: /* --delay */
2438
errno = 0;
2439
delay = strtof(arg, &tmp);
2440
if(errno != 0 or tmp == arg or *tmp != '\0'){
2441
argp_error(state, "Bad delay");
2442
}
2443
case 132: /* --retry */
2444
errno = 0;
2445
retry_interval = strtod(arg, &tmp);
2446
if(errno != 0 or tmp == arg or *tmp != '\0'
2447
or (retry_interval * 1000) > INT_MAX
2448
or retry_interval < 0){
2449
argp_error(state, "Bad retry interval");
2450
}
2451
break;
2452
case 133: /* --network-hook-dir */
2453
hookdir = arg;
2454
break;
2455
/*
2456
* These reproduce what we would get without ARGP_NO_HELP
2457
*/
2458
case '?': /* --help */
2459
argp_state_help(state, state->out_stream,
2460
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2461
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2462
case -3: /* --usage */
2463
argp_state_help(state, state->out_stream,
2464
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2465
case 'V': /* --version */
2466
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2467
exit(argp_err_exit_status);
2468
break;
2469
default:
2470
return ARGP_ERR_UNKNOWN;
2471
}
2472
return errno;
2473
}
2474
2475
struct argp argp = { .options = options, .parser = parse_opt,
2476
.args_doc = "",
2477
.doc = "Mandos client -- Get and decrypt"
2478
" passwords from a Mandos server" };
2479
ret = argp_parse(&argp, argc, argv,
2480
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2481
switch(ret){
2482
case 0:
2483
break;
2484
case ENOMEM:
2485
default:
2486
errno = ret;
2487
perror_plus("argp_parse");
2488
exitcode = EX_OSERR;
2489
goto end;
2490
case EINVAL:
2491
exitcode = EX_USAGE;
2492
goto end;
2493
}
2494
}
2495
2496
{
2497
/* Work around Debian bug #633582:
2498
<http://bugs.debian.org/633582> */
2499
2500
/* Re-raise privileges */
2501
ret_errno = raise_privileges();
2502
if(ret_errno != 0){
2503
errno = ret_errno;
2504
perror_plus("Failed to raise privileges");
2505
} else {
2506
struct stat st;
2507
2508
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2509
int seckey_fd = open(seckey, O_RDONLY);
2510
if(seckey_fd == -1){
2511
perror_plus("open");
2512
} else {
2513
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2514
if(ret == -1){
2515
perror_plus("fstat");
2516
} else {
2517
if(S_ISREG(st.st_mode)
2518
and st.st_uid == 0 and st.st_gid == 0){
2519
ret = fchown(seckey_fd, uid, gid);
2520
if(ret == -1){
2521
perror_plus("fchown");
2522
}
2523
}
2524
}
2525
close(seckey_fd);
2526
}
2527
}
2528
2529
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2530
int pubkey_fd = open(pubkey, O_RDONLY);
2531
if(pubkey_fd == -1){
2532
perror_plus("open");
2533
} else {
2534
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2535
if(ret == -1){
2536
perror_plus("fstat");
2537
} else {
2538
if(S_ISREG(st.st_mode)
2539
and st.st_uid == 0 and st.st_gid == 0){
2540
ret = fchown(pubkey_fd, uid, gid);
2541
if(ret == -1){
2542
perror_plus("fchown");
2543
}
2544
}
2545
}
2546
close(pubkey_fd);
2547
}
2548
}
2549
2550
if(strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2551
int dhparams_fd = open(dh_params_file, O_RDONLY);
2552
if(dhparams_fd == -1){
2553
perror_plus("open");
2554
} else {
2555
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2556
if(ret == -1){
2557
perror_plus("fstat");
2558
} else {
2559
if(S_ISREG(st.st_mode)
2560
and st.st_uid == 0 and st.st_gid == 0){
2561
ret = fchown(dhparams_fd, uid, gid);
2562
if(ret == -1){
2563
perror_plus("fchown");
2564
}
2565
}
2566
}
2567
close(dhparams_fd);
2568
}
2569
}
2570
2571
/* Lower privileges */
2572
ret_errno = lower_privileges();
2573
if(ret_errno != 0){
2574
errno = ret_errno;
2575
perror_plus("Failed to lower privileges");
2576
}
2577
}
2578
}
2579
2580
/* Remove invalid interface names (except "none") */
2581
{
2582
char *interface = NULL;
2583
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2584
interface))){
2585
if(strcmp(interface, "none") != 0
2586
and if_nametoindex(interface) == 0){
2587
if(interface[0] != '\0'){
2588
fprintf_plus(stderr, "Not using nonexisting interface"
2589
" \"%s\"\n", interface);
2590
}
2591
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2592
interface = NULL;
2593
}
2594
}
2595
}
2596
2597
/* Run network hooks */
2598
{
2599
if(mc.interfaces != NULL){
2600
interfaces_hooks = malloc(mc.interfaces_size);
2601
if(interfaces_hooks == NULL){
2602
perror_plus("malloc");
2603
goto end;
2604
}
2605
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2606
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2607
}
2608
run_network_hooks("start", interfaces_hooks != NULL ?
2609
interfaces_hooks : "", delay);
2610
}
2611
2612
if(not debug){
2613
avahi_set_log_function(empty_log);
2614
}
2615
2616
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2617
from the signal handler */
2618
/* Initialize the pseudo-RNG for Avahi */
2619
srand((unsigned int) time(NULL));
2620
simple_poll = avahi_simple_poll_new();
2621
if(simple_poll == NULL){
2622
fprintf_plus(stderr,
2623
"Avahi: Failed to create simple poll object.\n");
2624
exitcode = EX_UNAVAILABLE;
2625
goto end;
2626
}
2627
2628
sigemptyset(&sigterm_action.sa_mask);
2629
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2630
if(ret == -1){
2631
perror_plus("sigaddset");
2632
exitcode = EX_OSERR;
2633
goto end;
2634
}
2635
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2636
if(ret == -1){
2637
perror_plus("sigaddset");
2638
exitcode = EX_OSERR;
2639
goto end;
2640
}
2641
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2642
if(ret == -1){
2643
perror_plus("sigaddset");
2644
exitcode = EX_OSERR;
2645
goto end;
2646
}
2647
/* Need to check if the handler is SIG_IGN before handling:
2648
| [[info:libc:Initial Signal Actions]] |
2649
| [[info:libc:Basic Signal Handling]] |
2650
*/
2651
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2652
if(ret == -1){
2653
perror_plus("sigaction");
2654
return EX_OSERR;
2655
}
2656
if(old_sigterm_action.sa_handler != SIG_IGN){
2657
ret = sigaction(SIGINT, &sigterm_action, NULL);
2658
if(ret == -1){
2659
perror_plus("sigaction");
2660
exitcode = EX_OSERR;
2661
goto end;
2662
}
2663
}
2664
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2665
if(ret == -1){
2666
perror_plus("sigaction");
2667
return EX_OSERR;
2668
}
2669
if(old_sigterm_action.sa_handler != SIG_IGN){
2670
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2671
if(ret == -1){
2672
perror_plus("sigaction");
2673
exitcode = EX_OSERR;
2674
goto end;
2675
}
2676
}
2677
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2678
if(ret == -1){
2679
perror_plus("sigaction");
2680
return EX_OSERR;
2681
}
2682
if(old_sigterm_action.sa_handler != SIG_IGN){
2683
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2684
if(ret == -1){
2685
perror_plus("sigaction");
2686
exitcode = EX_OSERR;
2687
goto end;
2688
}
2689
}
2690
2691
/* If no interfaces were specified, make a list */
2692
if(mc.interfaces == NULL){
2693
struct dirent **direntries = NULL;
2694
/* Look for any good interfaces */
2695
ret = scandir(sys_class_net, &direntries, good_interface,
2696
alphasort);
2697
if(ret >= 1){
2698
/* Add all found interfaces to interfaces list */
2699
for(int i = 0; i < ret; ++i){
2700
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2701
direntries[i]->d_name);
2702
if(ret_errno != 0){
2703
errno = ret_errno;
2704
perror_plus("argz_add");
2705
free(direntries[i]);
2706
continue;
2707
}
2708
if(debug){
2709
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2710
direntries[i]->d_name);
2711
}
2712
free(direntries[i]);
2713
}
2714
free(direntries);
2715
} else {
2716
if(ret == 0){
2717
free(direntries);
2718
}
2719
fprintf_plus(stderr, "Could not find a network interface\n");
2720
exitcode = EXIT_FAILURE;
2721
goto end;
2722
}
2723
}
2724
2725
/* Bring up interfaces which are down, and remove any "none"s */
2726
{
2727
char *interface = NULL;
2728
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2729
interface))){
2730
/* If interface name is "none", stop bringing up interfaces.
2731
Also remove all instances of "none" from the list */
2732
if(strcmp(interface, "none") == 0){
2733
argz_delete(&mc.interfaces, &mc.interfaces_size,
2734
interface);
2735
interface = NULL;
2736
while((interface = argz_next(mc.interfaces,
2737
mc.interfaces_size, interface))){
2738
if(strcmp(interface, "none") == 0){
2739
argz_delete(&mc.interfaces, &mc.interfaces_size,
2740
interface);
2741
interface = NULL;
2742
}
2743
}
2744
break;
2745
}
2746
bool interface_was_up = interface_is_up(interface);
2747
errno = bring_up_interface(interface, delay);
2748
if(not interface_was_up){
2749
if(errno != 0){
2750
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2751
" %s\n", interface, strerror(errno));
2752
} else {
2753
errno = argz_add(&interfaces_to_take_down,
2754
&interfaces_to_take_down_size,
2755
interface);
2756
if(errno != 0){
2757
perror_plus("argz_add");
2758
}
2759
}
2760
}
2761
}
2762
if(debug and (interfaces_to_take_down == NULL)){
2763
fprintf_plus(stderr, "No interfaces were brought up\n");
2764
}
2765
}
2766
2767
/* If we only got one interface, explicitly use only that one */
2768
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2769
if(debug){
2770
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2771
mc.interfaces);
2772
}
2773
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2774
}
2775
2776
if(quit_now){
2777
goto end;
2778
}
2779
2780
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2781
if(ret == -1){
2782
fprintf_plus(stderr, "init_gnutls_global failed\n");
2783
exitcode = EX_UNAVAILABLE;
2784
goto end;
2785
} else {
2786
gnutls_initialized = true;
2787
}
2788
2789
if(quit_now){
2790
goto end;
2791
}
2792
2793
/* Try /run/tmp before /tmp */
2794
tempdir = mkdtemp(run_tempdir);
2795
if(tempdir == NULL and errno == ENOENT){
2796
if(debug){
2797
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2798
run_tempdir, old_tempdir);
2799
}
2800
tempdir = mkdtemp(old_tempdir);
2801
}
2802
if(tempdir == NULL){
2803
perror_plus("mkdtemp");
2804
goto end;
2805
}
2806
2807
if(quit_now){
2808
goto end;
2809
}
2810
2811
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2812
fprintf_plus(stderr, "init_gpgme failed\n");
2813
exitcode = EX_UNAVAILABLE;
2814
goto end;
2815
} else {
2816
gpgme_initialized = true;
2817
}
2818
2819
if(quit_now){
2820
goto end;
2821
}
2822
2823
if(connect_to != NULL){
2824
/* Connect directly, do not use Zeroconf */
2825
/* (Mainly meant for debugging) */
2826
char *address = strrchr(connect_to, ':');
2827
2828
if(address == NULL){
2829
fprintf_plus(stderr, "No colon in address\n");
2830
exitcode = EX_USAGE;
2831
goto end;
2832
}
2833
2834
if(quit_now){
2835
goto end;
2836
}
2837
2838
in_port_t port;
2839
errno = 0;
2840
tmpmax = strtoimax(address+1, &tmp, 10);
2841
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2842
or tmpmax != (in_port_t)tmpmax){
2843
fprintf_plus(stderr, "Bad port number\n");
2844
exitcode = EX_USAGE;
2845
goto end;
2846
}
2847
2848
if(quit_now){
2849
goto end;
2850
}
2851
2852
port = (in_port_t)tmpmax;
2853
*address = '\0';
2854
/* Colon in address indicates IPv6 */
2855
int af;
2856
if(strchr(connect_to, ':') != NULL){
2857
af = AF_INET6;
2858
/* Accept [] around IPv6 address - see RFC 5952 */
2859
if(connect_to[0] == '[' and address[-1] == ']')
2860
{
2861
connect_to++;
2862
address[-1] = '\0';
2863
}
2864
} else {
2865
af = AF_INET;
2866
}
2867
address = connect_to;
2868
2869
if(quit_now){
2870
goto end;
2871
}
2872
2873
while(not quit_now){
2874
ret = start_mandos_communication(address, port, if_index, af,
2875
&mc);
2876
if(quit_now or ret == 0){
2877
break;
2878
}
2879
if(debug){
2880
fprintf_plus(stderr, "Retrying in %d seconds\n",
2881
(int)retry_interval);
2882
}
2883
sleep((unsigned int)retry_interval);
2884
}
2885
2886
if(not quit_now){
2887
exitcode = EXIT_SUCCESS;
2888
}
2889
2890
goto end;
2891
}
2892
2893
if(quit_now){
2894
goto end;
2895
}
2896
2897
{
2898
AvahiServerConfig config;
2899
/* Do not publish any local Zeroconf records */
2900
avahi_server_config_init(&config);
2901
config.publish_hinfo = 0;
2902
config.publish_addresses = 0;
2903
config.publish_workstation = 0;
2904
config.publish_domain = 0;
2905
2906
/* Allocate a new server */
2907
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2908
&config, NULL, NULL, &ret_errno);
2909
2910
/* Free the Avahi configuration data */
2911
avahi_server_config_free(&config);
2912
}
2913
2914
/* Check if creating the Avahi server object succeeded */
2915
if(mc.server == NULL){
2916
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2917
avahi_strerror(ret_errno));
2918
exitcode = EX_UNAVAILABLE;
2919
goto end;
2920
}
2921
2922
if(quit_now){
2923
goto end;
2924
}
2925
2926
/* Create the Avahi service browser */
2927
sb = avahi_s_service_browser_new(mc.server, if_index,
2928
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2929
NULL, 0, browse_callback,
2930
(void *)&mc);
2931
if(sb == NULL){
2932
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2933
avahi_strerror(avahi_server_errno(mc.server)));
2934
exitcode = EX_UNAVAILABLE;
2935
goto end;
2936
}
2937
2938
if(quit_now){
2939
goto end;
2940
}
2941
2942
/* Run the main loop */
2943
2944
if(debug){
2945
fprintf_plus(stderr, "Starting Avahi loop search\n");
2946
}
2947
2948
ret = avahi_loop_with_timeout(simple_poll,
2949
(int)(retry_interval * 1000), &mc);
2950
if(debug){
2951
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2952
(ret == 0) ? "successfully" : "with error");
2953
}
2954
2955
end:
2956
2957
if(debug){
2958
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2959
}
2960
2961
/* Cleanup things */
2962
free(mc.interfaces);
2963
2964
if(sb != NULL)
2965
avahi_s_service_browser_free(sb);
2966
2967
if(mc.server != NULL)
2968
avahi_server_free(mc.server);
2969
2970
if(simple_poll != NULL)
2971
avahi_simple_poll_free(simple_poll);
2972
2973
if(gnutls_initialized){
2974
gnutls_certificate_free_credentials(mc.cred);
2975
gnutls_global_deinit();
2976
gnutls_dh_params_deinit(mc.dh_params);
2977
}
2978
2979
if(gpgme_initialized){
2980
gpgme_release(mc.ctx);
2981
}
2982
2983
/* Cleans up the circular linked list of Mandos servers the client
2984
has seen */
2985
if(mc.current_server != NULL){
2986
mc.current_server->prev->next = NULL;
2987
while(mc.current_server != NULL){
2988
server *next = mc.current_server->next;
2989
#ifdef __GNUC__
2990
#pragma GCC diagnostic push
2991
#pragma GCC diagnostic ignored "-Wcast-qual"
2992
#endif
2993
free((char *)(mc.current_server->ip));
2994
#ifdef __GNUC__
2995
#pragma GCC diagnostic pop
2996
#endif
2997
free(mc.current_server);
2998
mc.current_server = next;
2999
}
3000
}
3001
3002
/* Re-raise privileges */
3003
{
3004
ret_errno = raise_privileges();
3005
if(ret_errno != 0){
3006
errno = ret_errno;
3007
perror_plus("Failed to raise privileges");
3008
} else {
3009
3010
/* Run network hooks */
3011
run_network_hooks("stop", interfaces_hooks != NULL ?
3012
interfaces_hooks : "", delay);
3013
3014
/* Take down the network interfaces which were brought up */
3015
{
3016
char *interface = NULL;
3017
while((interface=argz_next(interfaces_to_take_down,
3018
interfaces_to_take_down_size,
3019
interface))){
3020
ret_errno = take_down_interface(interface);
3021
if(ret_errno != 0){
3022
errno = ret_errno;
3023
perror_plus("Failed to take down interface");
3024
}
3025
}
3026
if(debug and (interfaces_to_take_down == NULL)){
3027
fprintf_plus(stderr, "No interfaces needed to be taken"
3028
" down\n");
3029
}
3030
}
3031
}
3032
3033
ret_errno = lower_privileges_permanently();
3034
if(ret_errno != 0){
3035
errno = ret_errno;
3036
perror_plus("Failed to lower privileges permanently");
3037
}
3038
}
3039
3040
free(interfaces_to_take_down);
3041
free(interfaces_hooks);
3042
3043
/* Removes the GPGME temp directory and all files inside */
3044
if(tempdir != NULL){
3045
struct dirent **direntries = NULL;
3046
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3047
| O_NOFOLLOW
3048
| O_DIRECTORY
3049
| O_PATH));
3050
if(tempdir_fd == -1){
3051
perror_plus("open");
3052
} else {
3053
#ifdef __GLIBC__
3054
#if __GLIBC_PREREQ(2, 15)
3055
int numentries = scandirat(tempdir_fd, ".", &direntries,
3056
notdotentries, alphasort);
3057
#else /* not __GLIBC_PREREQ(2, 15) */
3058
int numentries = scandir(tempdir, &direntries, notdotentries,
3059
alphasort);
3060
#endif /* not __GLIBC_PREREQ(2, 15) */
3061
#else /* not __GLIBC__ */
3062
int numentries = scandir(tempdir, &direntries, notdotentries,
3063
alphasort);
3064
#endif /* not __GLIBC__ */
3065
if(numentries >= 0){
3066
for(int i = 0; i < numentries; i++){
3067
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3068
if(ret == -1){
3069
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3070
" \"%s\", 0): %s\n", tempdir,
3071
direntries[i]->d_name, strerror(errno));
3072
}
3073
free(direntries[i]);
3074
}
3075
3076
/* need to clean even if 0 because man page doesn't specify */
3077
free(direntries);
3078
if(numentries == -1){
3079
perror_plus("scandir");
3080
}
3081
ret = rmdir(tempdir);
3082
if(ret == -1 and errno != ENOENT){
3083
perror_plus("rmdir");
3084
}
3085
}
3086
close(tempdir_fd);
3087
}
3088
}
3089
3090
if(quit_now){
3091
sigemptyset(&old_sigterm_action.sa_mask);
3092
old_sigterm_action.sa_handler = SIG_DFL;
3093
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3094
&old_sigterm_action,
3095
NULL));
3096
if(ret == -1){
3097
perror_plus("sigaction");
3098
}
3099
do {
3100
ret = raise(signal_received);
3101
} while(ret != 0 and errno == EINTR);
3102
if(ret != 0){
3103
perror_plus("raise");
3104
abort();
3105
}
3106
TEMP_FAILURE_RETRY(pause());
3107
}
3108
3109
return exitcode;
3110
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0