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- Committer: Teddy Hogeborn
- Date: 2015-07-09 20:32:52 UTC
- mto: (237.7.594 trunk)
- mto: This revision was merged to the branch mainline in revision 325.
- Revision ID: teddy@recompile.se-20150709203252-u10p7trfsxc1a9yp
Install client Diffie-Hellman parameters into initramfs.
* debian/control (Package: mandos-client/Recommends): Added
"gnutls-bin | openssl" (to generate DH parameters).
* debian/mandos-client.postinst (create_dh_params): New function
called on package
configure.
* plugins.d/mandos-client.c (main): Bug fix: Work around Debian bug
#633582 also for the
"client-dhparams.pem" file.
* debian/control (Package: mandos-client/Recommends): Added
"gnutls-bin | openssl" (to generate DH parameters).
* debian/mandos-client.postinst (create_dh_params): New function
called on package
configure.
* plugins.d/mandos-client.c (main): Bug fix: Work around Debian bug
#633582 also for the
"client-dhparams.pem" file.
- files added:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- plugins.d
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- 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> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
59
getnameinfo() */
60
#include <fcntl.h> /* open(), unlinkat() */
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
*/
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
strtoimax() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
SIOCSIFFLAGS, if_indextoname(),
70
if_nametoindex(), IF_NAMESIZE */
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
*/
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit(),
77
unlinkat() */
78
#include <arpa/inet.h> /* inet_pton(), htons() */
79
#include <iso646.h> /* not, or, and */
80
#include <argp.h> /* struct argp_option, error_t, struct
81
argp_state, struct argp,
82
argp_parse(), ARGP_KEY_ARG,
83
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
84
#include <signal.h> /* sigemptyset(), sigaddset(),
85
sigaction(), SIGTERM, sig_atomic_t,
86
raise() */
87
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
88
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
90
WEXITSTATUS(), WTERMSIG() */
91
#include <grp.h> /* setgroups() */
92
#include <argz.h> /* argz_add_sep(), argz_next(),
93
argz_delete(), argz_append(),
94
argz_stringify(), argz_add(),
95
argz_count() */
96
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
97
EAI_SYSTEM, gai_strerror() */
98
99
#ifdef __linux__
100
#include <sys/klog.h> /* klogctl() */
101
#endif /* __linux__ */
102
103
/* Avahi */
104
/* All Avahi types, constants and functions
105
Avahi*, avahi_*,
106
AVAHI_* */
107
#include <avahi-core/core.h>
108
#include <avahi-core/lookup.h>
109
#include <avahi-core/log.h>
110
#include <avahi-common/simple-watch.h>
111
#include <avahi-common/malloc.h>
112
#include <avahi-common/error.h>
113
114
/* GnuTLS */
115
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
116
functions:
117
gnutls_*
118
init_gnutls_session(),
119
GNUTLS_* */
120
#include <gnutls/openpgp.h>
121
/* gnutls_certificate_set_openpgp_key_file(),
122
GNUTLS_OPENPGP_FMT_BASE64 */
123
124
/* GPGME */
125
#include <gpgme.h> /* All GPGME types, constants and
126
functions:
127
gpgme_*
128
GPGME_PROTOCOL_OpenPGP,
129
GPG_ERR_NO_* */
130
131
#define BUFFER_SIZE 256
132
133
#define PATHDIR "/conf/conf.d/mandos"
134
#define SECKEY "seckey.txt"
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
137
138
bool debug = false;
139
static const char mandos_protocol_version[] = "1";
140
const char *argp_program_version = "mandos-client " VERSION;
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
142
static const char sys_class_net[] = "/sys/class/net";
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
145
int hookdir_fd = -1;
146
uid_t uid = 65534;
147
gid_t gid = 65534;
148
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
151
const char *ip;
152
in_port_t port;
153
AvahiIfIndex if_index;
154
int af;
155
struct timespec last_seen;
156
struct server *next;
157
struct server *prev;
158
} server;
159
160
/* Used for passing in values through the Avahi callback functions */
161
typedef struct {
162
AvahiServer *server;
163
gnutls_certificate_credentials_t cred;
164
unsigned int dh_bits;
165
gnutls_dh_params_t dh_params;
166
const char *priority;
167
gpgme_ctx_t ctx;
168
server *current_server;
169
char *interfaces;
170
size_t interfaces_size;
171
} mandos_context;
172
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
175
176
sig_atomic_t quit_now = 0;
177
int signal_received = 0;
178
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
181
int e = errno;
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
184
errno = e;
185
perror(print_text);
186
}
187
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
190
va_list ap;
191
va_start (ap, format);
192
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
196
}
197
198
/*
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
200
* bytes. "buffer_capacity" is how much is currently allocated,
201
* "buffer_length" is how much is already used.
202
*/
203
__attribute__((nonnull, warn_unused_result))
204
size_t incbuffer(char **buffer, size_t buffer_length,
205
size_t buffer_capacity){
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
208
if(new_buf == NULL){
209
int old_errno = errno;
210
free(*buffer);
211
errno = old_errno;
212
*buffer = NULL;
213
return 0;
214
}
215
*buffer = new_buf;
216
buffer_capacity += BUFFER_SIZE;
217
}
218
return buffer_capacity;
219
}
220
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
225
int ret;
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
229
return false;
230
}
231
*new_server = (server){ .ip = strdup(ip),
232
.port = port,
233
.if_index = if_index,
234
.af = af };
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
237
free(new_server);
238
return false;
239
}
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
241
if(ret == -1){
242
perror_plus("clock_gettime");
243
#ifdef __GNUC__
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
246
#endif
247
free((char *)(new_server->ip));
248
#ifdef __GNUC__
249
#pragma GCC diagnostic pop
250
#endif
251
free(new_server);
252
return false;
253
}
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
259
} else {
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
265
}
266
return true;
267
}
268
269
/*
270
* Initialize GPGME.
271
*/
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
276
mandos_context *mc){
277
gpgme_error_t rc;
278
gpgme_engine_info_t engine_info;
279
280
/*
281
* Helper function to insert pub and seckey to the engine keyring.
282
*/
283
bool import_key(const char * const filename){
284
int ret;
285
int fd;
286
gpgme_data_t pgp_data;
287
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
289
if(fd == -1){
290
perror_plus("open");
291
return false;
292
}
293
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
295
if(rc != GPG_ERR_NO_ERROR){
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
298
return false;
299
}
300
301
rc = gpgme_op_import(mc->ctx, pgp_data);
302
if(rc != GPG_ERR_NO_ERROR){
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
305
return false;
306
}
307
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
309
if(ret == -1){
310
perror_plus("close");
311
}
312
gpgme_data_release(pgp_data);
313
return true;
314
}
315
316
if(debug){
317
fprintf_plus(stderr, "Initializing GPGME\n");
318
}
319
320
/* Init GPGME */
321
gpgme_check_version(NULL);
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
323
if(rc != GPG_ERR_NO_ERROR){
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
326
return false;
327
}
328
329
/* Set GPGME home directory for the OpenPGP engine only */
330
rc = gpgme_get_engine_info(&engine_info);
331
if(rc != GPG_ERR_NO_ERROR){
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
gpgme_strsource(rc), gpgme_strerror(rc));
334
return false;
335
}
336
while(engine_info != NULL){
337
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
338
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
339
engine_info->file_name, tempdir);
340
break;
341
}
342
engine_info = engine_info->next;
343
}
344
if(engine_info == NULL){
345
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
346
tempdir);
347
return false;
348
}
349
350
/* Create new GPGME "context" */
351
rc = gpgme_new(&(mc->ctx));
352
if(rc != GPG_ERR_NO_ERROR){
353
fprintf_plus(stderr, "Mandos plugin mandos-client: "
354
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
355
gpgme_strerror(rc));
356
return false;
357
}
358
359
if(not import_key(pubkey) or not import_key(seckey)){
360
return false;
361
}
362
363
return true;
364
}
365
366
/*
367
* Decrypt OpenPGP data.
368
* Returns -1 on error
369
*/
370
__attribute__((nonnull, warn_unused_result))
371
static ssize_t pgp_packet_decrypt(const char *cryptotext,
372
size_t crypto_size,
373
char **plaintext,
374
mandos_context *mc){
375
gpgme_data_t dh_crypto, dh_plain;
376
gpgme_error_t rc;
377
ssize_t ret;
378
size_t plaintext_capacity = 0;
379
ssize_t plaintext_length = 0;
380
381
if(debug){
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
383
}
384
385
/* Create new GPGME data buffer from memory cryptotext */
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
387
0);
388
if(rc != GPG_ERR_NO_ERROR){
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
391
return -1;
392
}
393
394
/* Create new empty GPGME data buffer for the plaintext */
395
rc = gpgme_data_new(&dh_plain);
396
if(rc != GPG_ERR_NO_ERROR){
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
400
gpgme_data_release(dh_crypto);
401
return -1;
402
}
403
404
/* Decrypt data from the cryptotext data buffer to the plaintext
405
data buffer */
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
407
if(rc != GPG_ERR_NO_ERROR){
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
410
plaintext_length = -1;
411
if(debug){
412
gpgme_decrypt_result_t result;
413
result = gpgme_op_decrypt_result(mc->ctx);
414
if(result == NULL){
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
416
} else {
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
421
if(result->file_name != NULL){
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
423
}
424
gpgme_recipient_t recipient;
425
recipient = result->recipients;
426
while(recipient != NULL){
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
433
? "No" : "Yes");
434
recipient = recipient->next;
435
}
436
}
437
}
438
goto decrypt_end;
439
}
440
441
if(debug){
442
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
443
}
444
445
/* Seek back to the beginning of the GPGME plaintext data buffer */
446
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
447
perror_plus("gpgme_data_seek");
448
plaintext_length = -1;
449
goto decrypt_end;
450
}
451
452
*plaintext = NULL;
453
while(true){
454
plaintext_capacity = incbuffer(plaintext,
455
(size_t)plaintext_length,
456
plaintext_capacity);
457
if(plaintext_capacity == 0){
458
perror_plus("incbuffer");
459
plaintext_length = -1;
460
goto decrypt_end;
461
}
462
463
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
464
BUFFER_SIZE);
465
/* Print the data, if any */
466
if(ret == 0){
467
/* EOF */
468
break;
469
}
470
if(ret < 0){
471
perror_plus("gpgme_data_read");
472
plaintext_length = -1;
473
goto decrypt_end;
474
}
475
plaintext_length += ret;
476
}
477
478
if(debug){
479
fprintf_plus(stderr, "Decrypted password is: ");
480
for(ssize_t i = 0; i < plaintext_length; i++){
481
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
482
}
483
fprintf(stderr, "\n");
484
}
485
486
decrypt_end:
487
488
/* Delete the GPGME cryptotext data buffer */
489
gpgme_data_release(dh_crypto);
490
491
/* Delete the GPGME plaintext data buffer */
492
gpgme_data_release(dh_plain);
493
return plaintext_length;
494
}
495
496
__attribute__((warn_unused_result, 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 = (int)TEMP_FAILURE_RETRY(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
TEMP_FAILURE_RETRY(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
memset(&to, 0, sizeof(to));
1134
if(af == AF_INET6){
1135
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
1136
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
1137
} else { /* IPv4 */
1138
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
1139
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
1140
}
1141
if(ret < 0 ){
1142
int e = errno;
1143
perror_plus("inet_pton");
1144
errno = e;
1145
goto mandos_end;
1146
}
1147
if(ret == 0){
1148
int e = errno;
1149
fprintf_plus(stderr, "Bad address: %s\n", ip);
1150
errno = e;
1151
goto mandos_end;
1152
}
1153
if(af == AF_INET6){
1154
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1155
if(IN6_IS_ADDR_LINKLOCAL
1156
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1157
if(if_index == AVAHI_IF_UNSPEC){
1158
fprintf_plus(stderr, "An IPv6 link-local address is"
1159
" incomplete without a network interface\n");
1160
errno = EINVAL;
1161
goto mandos_end;
1162
}
1163
/* Set the network interface number as scope */
1164
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1165
}
1166
} else {
1167
((struct sockaddr_in *)&to)->sin_port = htons(port);
1168
}
1169
1170
if(quit_now){
1171
errno = EINTR;
1172
goto mandos_end;
1173
}
1174
1175
if(debug){
1176
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1177
char interface[IF_NAMESIZE];
1178
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1179
perror_plus("if_indextoname");
1180
} else {
1181
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1182
"\n", ip, interface, (uintmax_t)port);
1183
}
1184
} else {
1185
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1186
ip, (uintmax_t)port);
1187
}
1188
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1189
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1190
if(af == AF_INET6){
1191
ret = getnameinfo((struct sockaddr *)&to,
1192
sizeof(struct sockaddr_in6),
1193
addrstr, sizeof(addrstr), NULL, 0,
1194
NI_NUMERICHOST);
1195
} else {
1196
ret = getnameinfo((struct sockaddr *)&to,
1197
sizeof(struct sockaddr_in),
1198
addrstr, sizeof(addrstr), NULL, 0,
1199
NI_NUMERICHOST);
1200
}
1201
if(ret == EAI_SYSTEM){
1202
perror_plus("getnameinfo");
1203
} else if(ret != 0) {
1204
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1205
} else if(strcmp(addrstr, ip) != 0){
1206
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1207
}
1208
}
1209
1210
if(quit_now){
1211
errno = EINTR;
1212
goto mandos_end;
1213
}
1214
1215
while(true){
1216
if(af == AF_INET6){
1217
ret = connect(tcp_sd, (struct sockaddr *)&to,
1218
sizeof(struct sockaddr_in6));
1219
} else {
1220
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1221
sizeof(struct sockaddr_in));
1222
}
1223
if(ret < 0){
1224
if(errno == ENETUNREACH
1225
and if_index != AVAHI_IF_UNSPEC
1226
and connect_to == NULL
1227
and not route_added and
1228
((af == AF_INET6 and not
1229
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1230
&to)->sin6_addr)))
1231
or (af == AF_INET and
1232
/* Not a a IPv4LL address */
1233
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1234
& 0xFFFF0000L) != 0xA9FE0000L))){
1235
/* Work around Avahi bug - Avahi does not announce link-local
1236
addresses if it has a global address, so local hosts with
1237
*only* a link-local address (e.g. Mandos clients) cannot
1238
connect to a Mandos server announced by Avahi on a server
1239
host with a global address. Work around this by retrying
1240
with an explicit route added with the server's address.
1241
1242
Avahi bug reference:
1243
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1244
https://bugs.debian.org/587961
1245
*/
1246
if(debug){
1247
fprintf_plus(stderr, "Mandos server unreachable, trying"
1248
" direct route\n");
1249
}
1250
int e = errno;
1251
route_added = add_local_route(ip, if_index);
1252
if(route_added){
1253
continue;
1254
}
1255
errno = e;
1256
}
1257
if(errno != ECONNREFUSED or debug){
1258
int e = errno;
1259
perror_plus("connect");
1260
errno = e;
1261
}
1262
goto mandos_end;
1263
}
1264
1265
if(quit_now){
1266
errno = EINTR;
1267
goto mandos_end;
1268
}
1269
break;
1270
}
1271
1272
const char *out = mandos_protocol_version;
1273
written = 0;
1274
while(true){
1275
size_t out_size = strlen(out);
1276
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1277
out_size - written));
1278
if(ret == -1){
1279
int e = errno;
1280
perror_plus("write");
1281
errno = e;
1282
goto mandos_end;
1283
}
1284
written += (size_t)ret;
1285
if(written < out_size){
1286
continue;
1287
} else {
1288
if(out == mandos_protocol_version){
1289
written = 0;
1290
out = "\r\n";
1291
} else {
1292
break;
1293
}
1294
}
1295
1296
if(quit_now){
1297
errno = EINTR;
1298
goto mandos_end;
1299
}
1300
}
1301
1302
if(debug){
1303
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1304
}
1305
1306
if(quit_now){
1307
errno = EINTR;
1308
goto mandos_end;
1309
}
1310
1311
/* This casting via intptr_t is to eliminate warning about casting
1312
an int to a pointer type. This is exactly how the GnuTLS Guile
1313
function "set-session-transport-fd!" does it. */
1314
gnutls_transport_set_ptr(session,
1315
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1316
1317
if(quit_now){
1318
errno = EINTR;
1319
goto mandos_end;
1320
}
1321
1322
do {
1323
ret = gnutls_handshake(session);
1324
if(quit_now){
1325
errno = EINTR;
1326
goto mandos_end;
1327
}
1328
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1329
1330
if(ret != GNUTLS_E_SUCCESS){
1331
if(debug){
1332
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
1333
gnutls_perror(ret);
1334
}
1335
errno = EPROTO;
1336
goto mandos_end;
1337
}
1338
1339
/* Read OpenPGP packet that contains the wanted password */
1340
1341
if(debug){
1342
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1343
" %s\n", ip);
1344
}
1345
1346
while(true){
1347
1348
if(quit_now){
1349
errno = EINTR;
1350
goto mandos_end;
1351
}
1352
1353
buffer_capacity = incbuffer(&buffer, buffer_length,
1354
buffer_capacity);
1355
if(buffer_capacity == 0){
1356
int e = errno;
1357
perror_plus("incbuffer");
1358
errno = e;
1359
goto mandos_end;
1360
}
1361
1362
if(quit_now){
1363
errno = EINTR;
1364
goto mandos_end;
1365
}
1366
1367
sret = gnutls_record_recv(session, buffer+buffer_length,
1368
BUFFER_SIZE);
1369
if(sret == 0){
1370
break;
1371
}
1372
if(sret < 0){
1373
switch(sret){
1374
case GNUTLS_E_INTERRUPTED:
1375
case GNUTLS_E_AGAIN:
1376
break;
1377
case GNUTLS_E_REHANDSHAKE:
1378
do {
1379
ret = gnutls_handshake(session);
1380
1381
if(quit_now){
1382
errno = EINTR;
1383
goto mandos_end;
1384
}
1385
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1386
if(ret < 0){
1387
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1388
"***\n");
1389
gnutls_perror(ret);
1390
errno = EPROTO;
1391
goto mandos_end;
1392
}
1393
break;
1394
default:
1395
fprintf_plus(stderr, "Unknown error while reading data from"
1396
" encrypted session with Mandos server\n");
1397
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1398
errno = EIO;
1399
goto mandos_end;
1400
}
1401
} else {
1402
buffer_length += (size_t) sret;
1403
}
1404
}
1405
1406
if(debug){
1407
fprintf_plus(stderr, "Closing TLS session\n");
1408
}
1409
1410
if(quit_now){
1411
errno = EINTR;
1412
goto mandos_end;
1413
}
1414
1415
do {
1416
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1417
if(quit_now){
1418
errno = EINTR;
1419
goto mandos_end;
1420
}
1421
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1422
1423
if(buffer_length > 0){
1424
ssize_t decrypted_buffer_size;
1425
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1426
&decrypted_buffer, mc);
1427
if(decrypted_buffer_size >= 0){
1428
1429
written = 0;
1430
while(written < (size_t) decrypted_buffer_size){
1431
if(quit_now){
1432
errno = EINTR;
1433
goto mandos_end;
1434
}
1435
1436
ret = (int)fwrite(decrypted_buffer + written, 1,
1437
(size_t)decrypted_buffer_size - written,
1438
stdout);
1439
if(ret == 0 and ferror(stdout)){
1440
int e = errno;
1441
if(debug){
1442
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1443
strerror(errno));
1444
}
1445
errno = e;
1446
goto mandos_end;
1447
}
1448
written += (size_t)ret;
1449
}
1450
retval = 0;
1451
}
1452
}
1453
1454
/* Shutdown procedure */
1455
1456
mandos_end:
1457
{
1458
if(route_added){
1459
if(not delete_local_route(ip, if_index)){
1460
fprintf_plus(stderr, "Failed to delete local route to %s on"
1461
" interface %d", ip, if_index);
1462
}
1463
}
1464
int e = errno;
1465
free(decrypted_buffer);
1466
free(buffer);
1467
if(tcp_sd >= 0){
1468
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1469
}
1470
if(ret == -1){
1471
if(e == 0){
1472
e = errno;
1473
}
1474
perror_plus("close");
1475
}
1476
gnutls_deinit(session);
1477
errno = e;
1478
if(quit_now){
1479
errno = EINTR;
1480
retval = -1;
1481
}
1482
}
1483
return retval;
1484
}
1485
1486
__attribute__((nonnull))
1487
static void resolve_callback(AvahiSServiceResolver *r,
1488
AvahiIfIndex interface,
1489
AvahiProtocol proto,
1490
AvahiResolverEvent event,
1491
const char *name,
1492
const char *type,
1493
const char *domain,
1494
const char *host_name,
1495
const AvahiAddress *address,
1496
uint16_t port,
1497
AVAHI_GCC_UNUSED AvahiStringList *txt,
1498
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1499
flags,
1500
void *mc){
1501
if(r == NULL){
1502
return;
1503
}
1504
1505
/* Called whenever a service has been resolved successfully or
1506
timed out */
1507
1508
if(quit_now){
1509
avahi_s_service_resolver_free(r);
1510
return;
1511
}
1512
1513
switch(event){
1514
default:
1515
case AVAHI_RESOLVER_FAILURE:
1516
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1517
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1518
domain,
1519
avahi_strerror(avahi_server_errno
1520
(((mandos_context*)mc)->server)));
1521
break;
1522
1523
case AVAHI_RESOLVER_FOUND:
1524
{
1525
char ip[AVAHI_ADDRESS_STR_MAX];
1526
avahi_address_snprint(ip, sizeof(ip), address);
1527
if(debug){
1528
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1529
PRIdMAX ") on port %" PRIu16 "\n", name,
1530
host_name, ip, (intmax_t)interface, port);
1531
}
1532
int ret = start_mandos_communication(ip, (in_port_t)port,
1533
interface,
1534
avahi_proto_to_af(proto),
1535
mc);
1536
if(ret == 0){
1537
avahi_simple_poll_quit(simple_poll);
1538
} else {
1539
if(not add_server(ip, (in_port_t)port, interface,
1540
avahi_proto_to_af(proto),
1541
&((mandos_context*)mc)->current_server)){
1542
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1543
" list\n", name);
1544
}
1545
}
1546
}
1547
}
1548
avahi_s_service_resolver_free(r);
1549
}
1550
1551
static void browse_callback(AvahiSServiceBrowser *b,
1552
AvahiIfIndex interface,
1553
AvahiProtocol protocol,
1554
AvahiBrowserEvent event,
1555
const char *name,
1556
const char *type,
1557
const char *domain,
1558
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1559
flags,
1560
void *mc){
1561
if(b == NULL){
1562
return;
1563
}
1564
1565
/* Called whenever a new services becomes available on the LAN or
1566
is removed from the LAN */
1567
1568
if(quit_now){
1569
return;
1570
}
1571
1572
switch(event){
1573
default:
1574
case AVAHI_BROWSER_FAILURE:
1575
1576
fprintf_plus(stderr, "(Avahi browser) %s\n",
1577
avahi_strerror(avahi_server_errno
1578
(((mandos_context*)mc)->server)));
1579
avahi_simple_poll_quit(simple_poll);
1580
return;
1581
1582
case AVAHI_BROWSER_NEW:
1583
/* We ignore the returned Avahi resolver object. In the callback
1584
function we free it. If the Avahi server is terminated before
1585
the callback function is called the Avahi server will free the
1586
resolver for us. */
1587
1588
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1589
interface, protocol, name, type,
1590
domain, protocol, 0,
1591
resolve_callback, mc) == NULL)
1592
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1593
" %s\n", name,
1594
avahi_strerror(avahi_server_errno
1595
(((mandos_context*)mc)->server)));
1596
break;
1597
1598
case AVAHI_BROWSER_REMOVE:
1599
break;
1600
1601
case AVAHI_BROWSER_ALL_FOR_NOW:
1602
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1603
if(debug){
1604
fprintf_plus(stderr, "No Mandos server found, still"
1605
" searching...\n");
1606
}
1607
break;
1608
}
1609
}
1610
1611
/* Signal handler that stops main loop after SIGTERM */
1612
static void handle_sigterm(int sig){
1613
if(quit_now){
1614
return;
1615
}
1616
quit_now = 1;
1617
signal_received = sig;
1618
int old_errno = errno;
1619
/* set main loop to exit */
1620
if(simple_poll != NULL){
1621
avahi_simple_poll_quit(simple_poll);
1622
}
1623
errno = old_errno;
1624
}
1625
1626
__attribute__((nonnull, warn_unused_result))
1627
bool get_flags(const char *ifname, struct ifreq *ifr){
1628
int ret;
1629
error_t ret_errno;
1630
1631
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1632
if(s < 0){
1633
ret_errno = errno;
1634
perror_plus("socket");
1635
errno = ret_errno;
1636
return false;
1637
}
1638
strcpy(ifr->ifr_name, ifname);
1639
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1640
if(ret == -1){
1641
if(debug){
1642
ret_errno = errno;
1643
perror_plus("ioctl SIOCGIFFLAGS");
1644
errno = ret_errno;
1645
}
1646
return false;
1647
}
1648
return true;
1649
}
1650
1651
__attribute__((nonnull, warn_unused_result))
1652
bool good_flags(const char *ifname, const struct ifreq *ifr){
1653
1654
/* Reject the loopback device */
1655
if(ifr->ifr_flags & IFF_LOOPBACK){
1656
if(debug){
1657
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1658
ifname);
1659
}
1660
return false;
1661
}
1662
/* Accept point-to-point devices only if connect_to is specified */
1663
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1664
if(debug){
1665
fprintf_plus(stderr, "Accepting point-to-point interface"
1666
" \"%s\"\n", ifname);
1667
}
1668
return true;
1669
}
1670
/* Otherwise, reject non-broadcast-capable devices */
1671
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1672
if(debug){
1673
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1674
" \"%s\"\n", ifname);
1675
}
1676
return false;
1677
}
1678
/* Reject non-ARP interfaces (including dummy interfaces) */
1679
if(ifr->ifr_flags & IFF_NOARP){
1680
if(debug){
1681
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1682
ifname);
1683
}
1684
return false;
1685
}
1686
1687
/* Accept this device */
1688
if(debug){
1689
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1690
}
1691
return true;
1692
}
1693
1694
/*
1695
* This function determines if a directory entry in /sys/class/net
1696
* corresponds to an acceptable network device.
1697
* (This function is passed to scandir(3) as a filter function.)
1698
*/
1699
__attribute__((nonnull, warn_unused_result))
1700
int good_interface(const struct dirent *if_entry){
1701
if(if_entry->d_name[0] == '.'){
1702
return 0;
1703
}
1704
1705
struct ifreq ifr;
1706
if(not get_flags(if_entry->d_name, &ifr)){
1707
if(debug){
1708
fprintf_plus(stderr, "Failed to get flags for interface "
1709
"\"%s\"\n", if_entry->d_name);
1710
}
1711
return 0;
1712
}
1713
1714
if(not good_flags(if_entry->d_name, &ifr)){
1715
return 0;
1716
}
1717
return 1;
1718
}
1719
1720
/*
1721
* This function determines if a network interface is up.
1722
*/
1723
__attribute__((nonnull, warn_unused_result))
1724
bool interface_is_up(const char *interface){
1725
struct ifreq ifr;
1726
if(not get_flags(interface, &ifr)){
1727
if(debug){
1728
fprintf_plus(stderr, "Failed to get flags for interface "
1729
"\"%s\"\n", interface);
1730
}
1731
return false;
1732
}
1733
1734
return (bool)(ifr.ifr_flags & IFF_UP);
1735
}
1736
1737
/*
1738
* This function determines if a network interface is running
1739
*/
1740
__attribute__((nonnull, warn_unused_result))
1741
bool interface_is_running(const char *interface){
1742
struct ifreq ifr;
1743
if(not get_flags(interface, &ifr)){
1744
if(debug){
1745
fprintf_plus(stderr, "Failed to get flags for interface "
1746
"\"%s\"\n", interface);
1747
}
1748
return false;
1749
}
1750
1751
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1752
}
1753
1754
__attribute__((nonnull, pure, warn_unused_result))
1755
int notdotentries(const struct dirent *direntry){
1756
/* Skip "." and ".." */
1757
if(direntry->d_name[0] == '.'
1758
and (direntry->d_name[1] == '\0'
1759
or (direntry->d_name[1] == '.'
1760
and direntry->d_name[2] == '\0'))){
1761
return 0;
1762
}
1763
return 1;
1764
}
1765
1766
/* Is this directory entry a runnable program? */
1767
__attribute__((nonnull, warn_unused_result))
1768
int runnable_hook(const struct dirent *direntry){
1769
int ret;
1770
size_t sret;
1771
struct stat st;
1772
1773
if((direntry->d_name)[0] == '\0'){
1774
/* Empty name? */
1775
return 0;
1776
}
1777
1778
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1779
"abcdefghijklmnopqrstuvwxyz"
1780
"0123456789"
1781
"_.-");
1782
if((direntry->d_name)[sret] != '\0'){
1783
/* Contains non-allowed characters */
1784
if(debug){
1785
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1786
direntry->d_name);
1787
}
1788
return 0;
1789
}
1790
1791
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1792
if(ret == -1){
1793
if(debug){
1794
perror_plus("Could not stat hook");
1795
}
1796
return 0;
1797
}
1798
if(not (S_ISREG(st.st_mode))){
1799
/* Not a regular file */
1800
if(debug){
1801
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1802
direntry->d_name);
1803
}
1804
return 0;
1805
}
1806
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1807
/* Not executable */
1808
if(debug){
1809
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1810
direntry->d_name);
1811
}
1812
return 0;
1813
}
1814
if(debug){
1815
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1816
direntry->d_name);
1817
}
1818
return 1;
1819
}
1820
1821
__attribute__((nonnull, warn_unused_result))
1822
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1823
mandos_context *mc){
1824
int ret;
1825
struct timespec now;
1826
struct timespec waited_time;
1827
intmax_t block_time;
1828
1829
while(true){
1830
if(mc->current_server == NULL){
1831
if(debug){
1832
fprintf_plus(stderr, "Wait until first server is found."
1833
" No timeout!\n");
1834
}
1835
ret = avahi_simple_poll_iterate(s, -1);
1836
} else {
1837
if(debug){
1838
fprintf_plus(stderr, "Check current_server if we should run"
1839
" it, or wait\n");
1840
}
1841
/* the current time */
1842
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1843
if(ret == -1){
1844
perror_plus("clock_gettime");
1845
return -1;
1846
}
1847
/* Calculating in ms how long time between now and server
1848
who we visted longest time ago. Now - last seen. */
1849
waited_time.tv_sec = (now.tv_sec
1850
- mc->current_server->last_seen.tv_sec);
1851
waited_time.tv_nsec = (now.tv_nsec
1852
- mc->current_server->last_seen.tv_nsec);
1853
/* total time is 10s/10,000ms.
1854
Converting to s from ms by dividing by 1,000,
1855
and ns to ms by dividing by 1,000,000. */
1856
block_time = ((retry_interval
1857
- ((intmax_t)waited_time.tv_sec * 1000))
1858
- ((intmax_t)waited_time.tv_nsec / 1000000));
1859
1860
if(debug){
1861
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1862
block_time);
1863
}
1864
1865
if(block_time <= 0){
1866
ret = start_mandos_communication(mc->current_server->ip,
1867
mc->current_server->port,
1868
mc->current_server->if_index,
1869
mc->current_server->af, mc);
1870
if(ret == 0){
1871
avahi_simple_poll_quit(s);
1872
return 0;
1873
}
1874
ret = clock_gettime(CLOCK_MONOTONIC,
1875
&mc->current_server->last_seen);
1876
if(ret == -1){
1877
perror_plus("clock_gettime");
1878
return -1;
1879
}
1880
mc->current_server = mc->current_server->next;
1881
block_time = 0; /* Call avahi to find new Mandos
1882
servers, but don't block */
1883
}
1884
1885
ret = avahi_simple_poll_iterate(s, (int)block_time);
1886
}
1887
if(ret != 0){
1888
if(ret > 0 or errno != EINTR){
1889
return (ret != 1) ? ret : 0;
1890
}
1891
}
1892
}
1893
}
1894
1895
__attribute__((nonnull))
1896
void run_network_hooks(const char *mode, const char *interface,
1897
const float delay){
1898
struct dirent **direntries = NULL;
1899
if(hookdir_fd == -1){
1900
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1901
| O_CLOEXEC);
1902
if(hookdir_fd == -1){
1903
if(errno == ENOENT){
1904
if(debug){
1905
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1906
" found\n", hookdir);
1907
}
1908
} else {
1909
perror_plus("open");
1910
}
1911
return;
1912
}
1913
}
1914
#ifdef __GLIBC__
1915
#if __GLIBC_PREREQ(2, 15)
1916
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1917
runnable_hook, alphasort);
1918
#else /* not __GLIBC_PREREQ(2, 15) */
1919
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1920
alphasort);
1921
#endif /* not __GLIBC_PREREQ(2, 15) */
1922
#else /* not __GLIBC__ */
1923
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1924
alphasort);
1925
#endif /* not __GLIBC__ */
1926
if(numhooks == -1){
1927
perror_plus("scandir");
1928
return;
1929
}
1930
struct dirent *direntry;
1931
int ret;
1932
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1933
if(devnull == -1){
1934
perror_plus("open(\"/dev/null\", O_RDONLY)");
1935
return;
1936
}
1937
for(int i = 0; i < numhooks; i++){
1938
direntry = direntries[i];
1939
if(debug){
1940
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1941
direntry->d_name);
1942
}
1943
pid_t hook_pid = fork();
1944
if(hook_pid == 0){
1945
/* Child */
1946
/* Raise privileges */
1947
errno = raise_privileges_permanently();
1948
if(errno != 0){
1949
perror_plus("Failed to raise privileges");
1950
_exit(EX_NOPERM);
1951
}
1952
/* Set group */
1953
errno = 0;
1954
ret = setgid(0);
1955
if(ret == -1){
1956
perror_plus("setgid");
1957
_exit(EX_NOPERM);
1958
}
1959
/* Reset supplementary groups */
1960
errno = 0;
1961
ret = setgroups(0, NULL);
1962
if(ret == -1){
1963
perror_plus("setgroups");
1964
_exit(EX_NOPERM);
1965
}
1966
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1967
if(ret == -1){
1968
perror_plus("setenv");
1969
_exit(EX_OSERR);
1970
}
1971
ret = setenv("DEVICE", interface, 1);
1972
if(ret == -1){
1973
perror_plus("setenv");
1974
_exit(EX_OSERR);
1975
}
1976
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1977
if(ret == -1){
1978
perror_plus("setenv");
1979
_exit(EX_OSERR);
1980
}
1981
ret = setenv("MODE", mode, 1);
1982
if(ret == -1){
1983
perror_plus("setenv");
1984
_exit(EX_OSERR);
1985
}
1986
char *delaystring;
1987
ret = asprintf(&delaystring, "%f", (double)delay);
1988
if(ret == -1){
1989
perror_plus("asprintf");
1990
_exit(EX_OSERR);
1991
}
1992
ret = setenv("DELAY", delaystring, 1);
1993
if(ret == -1){
1994
free(delaystring);
1995
perror_plus("setenv");
1996
_exit(EX_OSERR);
1997
}
1998
free(delaystring);
1999
if(connect_to != NULL){
2000
ret = setenv("CONNECT", connect_to, 1);
2001
if(ret == -1){
2002
perror_plus("setenv");
2003
_exit(EX_OSERR);
2004
}
2005
}
2006
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2007
direntry->d_name,
2008
O_RDONLY));
2009
if(hook_fd == -1){
2010
perror_plus("openat");
2011
_exit(EXIT_FAILURE);
2012
}
2013
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2014
perror_plus("close");
2015
_exit(EXIT_FAILURE);
2016
}
2017
ret = dup2(devnull, STDIN_FILENO);
2018
if(ret == -1){
2019
perror_plus("dup2(devnull, STDIN_FILENO)");
2020
_exit(EX_OSERR);
2021
}
2022
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
2023
if(ret == -1){
2024
perror_plus("close");
2025
_exit(EX_OSERR);
2026
}
2027
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2028
if(ret == -1){
2029
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2030
_exit(EX_OSERR);
2031
}
2032
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2033
environ) == -1){
2034
perror_plus("fexecve");
2035
_exit(EXIT_FAILURE);
2036
}
2037
} else {
2038
if(hook_pid == -1){
2039
perror_plus("fork");
2040
free(direntry);
2041
continue;
2042
}
2043
int status;
2044
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2045
perror_plus("waitpid");
2046
free(direntry);
2047
continue;
2048
}
2049
if(WIFEXITED(status)){
2050
if(WEXITSTATUS(status) != 0){
2051
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2052
" with status %d\n", direntry->d_name,
2053
WEXITSTATUS(status));
2054
free(direntry);
2055
continue;
2056
}
2057
} else if(WIFSIGNALED(status)){
2058
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2059
" signal %d\n", direntry->d_name,
2060
WTERMSIG(status));
2061
free(direntry);
2062
continue;
2063
} else {
2064
fprintf_plus(stderr, "Warning: network hook \"%s\""
2065
" crashed\n", direntry->d_name);
2066
free(direntry);
2067
continue;
2068
}
2069
}
2070
if(debug){
2071
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2072
direntry->d_name);
2073
}
2074
free(direntry);
2075
}
2076
free(direntries);
2077
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2078
perror_plus("close");
2079
} else {
2080
hookdir_fd = -1;
2081
}
2082
close(devnull);
2083
}
2084
2085
__attribute__((nonnull, warn_unused_result))
2086
error_t bring_up_interface(const char *const interface,
2087
const float delay){
2088
error_t old_errno = errno;
2089
int ret;
2090
struct ifreq network;
2091
unsigned int if_index = if_nametoindex(interface);
2092
if(if_index == 0){
2093
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2094
errno = old_errno;
2095
return ENXIO;
2096
}
2097
2098
if(quit_now){
2099
errno = old_errno;
2100
return EINTR;
2101
}
2102
2103
if(not interface_is_up(interface)){
2104
error_t ret_errno = 0, ioctl_errno = 0;
2105
if(not get_flags(interface, &network)){
2106
ret_errno = errno;
2107
fprintf_plus(stderr, "Failed to get flags for interface "
2108
"\"%s\"\n", interface);
2109
errno = old_errno;
2110
return ret_errno;
2111
}
2112
network.ifr_flags |= IFF_UP; /* set flag */
2113
2114
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2115
if(sd == -1){
2116
ret_errno = errno;
2117
perror_plus("socket");
2118
errno = old_errno;
2119
return ret_errno;
2120
}
2121
2122
if(quit_now){
2123
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2124
if(ret == -1){
2125
perror_plus("close");
2126
}
2127
errno = old_errno;
2128
return EINTR;
2129
}
2130
2131
if(debug){
2132
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2133
interface);
2134
}
2135
2136
/* Raise privileges */
2137
ret_errno = raise_privileges();
2138
if(ret_errno != 0){
2139
errno = ret_errno;
2140
perror_plus("Failed to raise privileges");
2141
}
2142
2143
#ifdef __linux__
2144
int ret_linux;
2145
bool restore_loglevel = false;
2146
if(ret_errno == 0){
2147
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2148
messages about the network interface to mess up the prompt */
2149
ret_linux = klogctl(8, NULL, 5);
2150
if(ret_linux == -1){
2151
perror_plus("klogctl");
2152
} else {
2153
restore_loglevel = true;
2154
}
2155
}
2156
#endif /* __linux__ */
2157
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2158
ioctl_errno = errno;
2159
#ifdef __linux__
2160
if(restore_loglevel){
2161
ret_linux = klogctl(7, NULL, 0);
2162
if(ret_linux == -1){
2163
perror_plus("klogctl");
2164
}
2165
}
2166
#endif /* __linux__ */
2167
2168
/* If raise_privileges() succeeded above */
2169
if(ret_errno == 0){
2170
/* Lower privileges */
2171
ret_errno = lower_privileges();
2172
if(ret_errno != 0){
2173
errno = ret_errno;
2174
perror_plus("Failed to lower privileges");
2175
}
2176
}
2177
2178
/* Close the socket */
2179
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2180
if(ret == -1){
2181
perror_plus("close");
2182
}
2183
2184
if(ret_setflags == -1){
2185
errno = ioctl_errno;
2186
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2187
errno = old_errno;
2188
return ioctl_errno;
2189
}
2190
} else if(debug){
2191
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2192
interface);
2193
}
2194
2195
/* Sleep checking until interface is running.
2196
Check every 0.25s, up to total time of delay */
2197
for(int i=0; i < delay * 4; i++){
2198
if(interface_is_running(interface)){
2199
break;
2200
}
2201
struct timespec sleeptime = { .tv_nsec = 250000000 };
2202
ret = nanosleep(&sleeptime, NULL);
2203
if(ret == -1 and errno != EINTR){
2204
perror_plus("nanosleep");
2205
}
2206
}
2207
2208
errno = old_errno;
2209
return 0;
2210
}
2211
2212
__attribute__((nonnull, warn_unused_result))
2213
error_t take_down_interface(const char *const interface){
2214
error_t old_errno = errno;
2215
struct ifreq network;
2216
unsigned int if_index = if_nametoindex(interface);
2217
if(if_index == 0){
2218
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2219
errno = old_errno;
2220
return ENXIO;
2221
}
2222
if(interface_is_up(interface)){
2223
error_t ret_errno = 0, ioctl_errno = 0;
2224
if(not get_flags(interface, &network) and debug){
2225
ret_errno = errno;
2226
fprintf_plus(stderr, "Failed to get flags for interface "
2227
"\"%s\"\n", interface);
2228
errno = old_errno;
2229
return ret_errno;
2230
}
2231
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2232
2233
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2234
if(sd == -1){
2235
ret_errno = errno;
2236
perror_plus("socket");
2237
errno = old_errno;
2238
return ret_errno;
2239
}
2240
2241
if(debug){
2242
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2243
interface);
2244
}
2245
2246
/* Raise privileges */
2247
ret_errno = raise_privileges();
2248
if(ret_errno != 0){
2249
errno = ret_errno;
2250
perror_plus("Failed to raise privileges");
2251
}
2252
2253
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2254
ioctl_errno = errno;
2255
2256
/* If raise_privileges() succeeded above */
2257
if(ret_errno == 0){
2258
/* Lower privileges */
2259
ret_errno = lower_privileges();
2260
if(ret_errno != 0){
2261
errno = ret_errno;
2262
perror_plus("Failed to lower privileges");
2263
}
2264
}
2265
2266
/* Close the socket */
2267
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
2268
if(ret == -1){
2269
perror_plus("close");
2270
}
2271
2272
if(ret_setflags == -1){
2273
errno = ioctl_errno;
2274
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2275
errno = old_errno;
2276
return ioctl_errno;
2277
}
2278
} else if(debug){
2279
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2280
interface);
2281
}
2282
2283
errno = old_errno;
2284
return 0;
2285
}
2286
2287
int main(int argc, char *argv[]){
2288
mandos_context mc = { .server = NULL, .dh_bits = 0,
2289
.priority = "SECURE256:!CTYPE-X.509:"
2290
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
2291
.interfaces = NULL, .interfaces_size = 0 };
2292
AvahiSServiceBrowser *sb = NULL;
2293
error_t ret_errno;
2294
int ret;
2295
intmax_t tmpmax;
2296
char *tmp;
2297
int exitcode = EXIT_SUCCESS;
2298
char *interfaces_to_take_down = NULL;
2299
size_t interfaces_to_take_down_size = 0;
2300
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2301
char old_tempdir[] = "/tmp/mandosXXXXXX";
2302
char *tempdir = NULL;
2303
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2304
const char *seckey = PATHDIR "/" SECKEY;
2305
const char *pubkey = PATHDIR "/" PUBKEY;
2306
const char *dh_params_file = NULL;
2307
char *interfaces_hooks = NULL;
2308
2309
bool gnutls_initialized = false;
2310
bool gpgme_initialized = false;
2311
float delay = 2.5f;
2312
double retry_interval = 10; /* 10s between trying a server and
2313
retrying the same server again */
2314
2315
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2316
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2317
2318
uid = getuid();
2319
gid = getgid();
2320
2321
/* Lower any group privileges we might have, just to be safe */
2322
errno = 0;
2323
ret = setgid(gid);
2324
if(ret == -1){
2325
perror_plus("setgid");
2326
}
2327
2328
/* Lower user privileges (temporarily) */
2329
errno = 0;
2330
ret = seteuid(uid);
2331
if(ret == -1){
2332
perror_plus("seteuid");
2333
}
2334
2335
if(quit_now){
2336
goto end;
2337
}
2338
2339
{
2340
struct argp_option options[] = {
2341
{ .name = "debug", .key = 128,
2342
.doc = "Debug mode", .group = 3 },
2343
{ .name = "connect", .key = 'c',
2344
.arg = "ADDRESS:PORT",
2345
.doc = "Connect directly to a specific Mandos server",
2346
.group = 1 },
2347
{ .name = "interface", .key = 'i',
2348
.arg = "NAME",
2349
.doc = "Network interface that will be used to search for"
2350
" Mandos servers",
2351
.group = 1 },
2352
{ .name = "seckey", .key = 's',
2353
.arg = "FILE",
2354
.doc = "OpenPGP secret key file base name",
2355
.group = 1 },
2356
{ .name = "pubkey", .key = 'p',
2357
.arg = "FILE",
2358
.doc = "OpenPGP public key file base name",
2359
.group = 2 },
2360
{ .name = "dh-bits", .key = 129,
2361
.arg = "BITS",
2362
.doc = "Bit length of the prime number used in the"
2363
" Diffie-Hellman key exchange",
2364
.group = 2 },
2365
{ .name = "dh-params", .key = 134,
2366
.arg = "FILE",
2367
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2368
" for the Diffie-Hellman key exchange",
2369
.group = 2 },
2370
{ .name = "priority", .key = 130,
2371
.arg = "STRING",
2372
.doc = "GnuTLS priority string for the TLS handshake",
2373
.group = 1 },
2374
{ .name = "delay", .key = 131,
2375
.arg = "SECONDS",
2376
.doc = "Maximum delay to wait for interface startup",
2377
.group = 2 },
2378
{ .name = "retry", .key = 132,
2379
.arg = "SECONDS",
2380
.doc = "Retry interval used when denied by the Mandos server",
2381
.group = 2 },
2382
{ .name = "network-hook-dir", .key = 133,
2383
.arg = "DIR",
2384
.doc = "Directory where network hooks are located",
2385
.group = 2 },
2386
/*
2387
* These reproduce what we would get without ARGP_NO_HELP
2388
*/
2389
{ .name = "help", .key = '?',
2390
.doc = "Give this help list", .group = -1 },
2391
{ .name = "usage", .key = -3,
2392
.doc = "Give a short usage message", .group = -1 },
2393
{ .name = "version", .key = 'V',
2394
.doc = "Print program version", .group = -1 },
2395
{ .name = NULL }
2396
};
2397
2398
error_t parse_opt(int key, char *arg,
2399
struct argp_state *state){
2400
errno = 0;
2401
switch(key){
2402
case 128: /* --debug */
2403
debug = true;
2404
break;
2405
case 'c': /* --connect */
2406
connect_to = arg;
2407
break;
2408
case 'i': /* --interface */
2409
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2410
arg, (int)',');
2411
if(ret_errno != 0){
2412
argp_error(state, "%s", strerror(ret_errno));
2413
}
2414
break;
2415
case 's': /* --seckey */
2416
seckey = arg;
2417
break;
2418
case 'p': /* --pubkey */
2419
pubkey = arg;
2420
break;
2421
case 129: /* --dh-bits */
2422
errno = 0;
2423
tmpmax = strtoimax(arg, &tmp, 10);
2424
if(errno != 0 or tmp == arg or *tmp != '\0'
2425
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2426
argp_error(state, "Bad number of DH bits");
2427
}
2428
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2429
break;
2430
case 134: /* --dh-params */
2431
dh_params_file = arg;
2432
break;
2433
case 130: /* --priority */
2434
mc.priority = arg;
2435
break;
2436
case 131: /* --delay */
2437
errno = 0;
2438
delay = strtof(arg, &tmp);
2439
if(errno != 0 or tmp == arg or *tmp != '\0'){
2440
argp_error(state, "Bad delay");
2441
}
2442
case 132: /* --retry */
2443
errno = 0;
2444
retry_interval = strtod(arg, &tmp);
2445
if(errno != 0 or tmp == arg or *tmp != '\0'
2446
or (retry_interval * 1000) > INT_MAX
2447
or retry_interval < 0){
2448
argp_error(state, "Bad retry interval");
2449
}
2450
break;
2451
case 133: /* --network-hook-dir */
2452
hookdir = arg;
2453
break;
2454
/*
2455
* These reproduce what we would get without ARGP_NO_HELP
2456
*/
2457
case '?': /* --help */
2458
argp_state_help(state, state->out_stream,
2459
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2460
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2461
case -3: /* --usage */
2462
argp_state_help(state, state->out_stream,
2463
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2464
case 'V': /* --version */
2465
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2466
exit(argp_err_exit_status);
2467
break;
2468
default:
2469
return ARGP_ERR_UNKNOWN;
2470
}
2471
return errno;
2472
}
2473
2474
struct argp argp = { .options = options, .parser = parse_opt,
2475
.args_doc = "",
2476
.doc = "Mandos client -- Get and decrypt"
2477
" passwords from a Mandos server" };
2478
ret = argp_parse(&argp, argc, argv,
2479
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2480
switch(ret){
2481
case 0:
2482
break;
2483
case ENOMEM:
2484
default:
2485
errno = ret;
2486
perror_plus("argp_parse");
2487
exitcode = EX_OSERR;
2488
goto end;
2489
case EINVAL:
2490
exitcode = EX_USAGE;
2491
goto end;
2492
}
2493
}
2494
2495
{
2496
/* Work around Debian bug #633582:
2497
<http://bugs.debian.org/633582> */
2498
2499
/* Re-raise privileges */
2500
ret_errno = raise_privileges();
2501
if(ret_errno != 0){
2502
errno = ret_errno;
2503
perror_plus("Failed to raise privileges");
2504
} else {
2505
struct stat st;
2506
2507
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2508
int seckey_fd = open(seckey, O_RDONLY);
2509
if(seckey_fd == -1){
2510
perror_plus("open");
2511
} else {
2512
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2513
if(ret == -1){
2514
perror_plus("fstat");
2515
} else {
2516
if(S_ISREG(st.st_mode)
2517
and st.st_uid == 0 and st.st_gid == 0){
2518
ret = fchown(seckey_fd, uid, gid);
2519
if(ret == -1){
2520
perror_plus("fchown");
2521
}
2522
}
2523
}
2524
TEMP_FAILURE_RETRY(close(seckey_fd));
2525
}
2526
}
2527
2528
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2529
int pubkey_fd = open(pubkey, O_RDONLY);
2530
if(pubkey_fd == -1){
2531
perror_plus("open");
2532
} else {
2533
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2534
if(ret == -1){
2535
perror_plus("fstat");
2536
} else {
2537
if(S_ISREG(st.st_mode)
2538
and st.st_uid == 0 and st.st_gid == 0){
2539
ret = fchown(pubkey_fd, uid, gid);
2540
if(ret == -1){
2541
perror_plus("fchown");
2542
}
2543
}
2544
}
2545
TEMP_FAILURE_RETRY(close(pubkey_fd));
2546
}
2547
}
2548
2549
if(strcmp(dh_params_file, PATHDIR "/client-dhparams.pem" )
2550
== 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
TEMP_FAILURE_RETRY(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
perror_plus("Failed to bring up interface");
2751
} else {
2752
errno = argz_add(&interfaces_to_take_down,
2753
&interfaces_to_take_down_size,
2754
interface);
2755
if(errno != 0){
2756
perror_plus("argz_add");
2757
}
2758
}
2759
}
2760
}
2761
if(debug and (interfaces_to_take_down == NULL)){
2762
fprintf_plus(stderr, "No interfaces were brought up\n");
2763
}
2764
}
2765
2766
/* If we only got one interface, explicitly use only that one */
2767
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2768
if(debug){
2769
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2770
mc.interfaces);
2771
}
2772
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2773
}
2774
2775
if(quit_now){
2776
goto end;
2777
}
2778
2779
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2780
if(ret == -1){
2781
fprintf_plus(stderr, "init_gnutls_global failed\n");
2782
exitcode = EX_UNAVAILABLE;
2783
goto end;
2784
} else {
2785
gnutls_initialized = true;
2786
}
2787
2788
if(quit_now){
2789
goto end;
2790
}
2791
2792
/* Try /run/tmp before /tmp */
2793
tempdir = mkdtemp(run_tempdir);
2794
if(tempdir == NULL and errno == ENOENT){
2795
if(debug){
2796
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2797
run_tempdir, old_tempdir);
2798
}
2799
tempdir = mkdtemp(old_tempdir);
2800
}
2801
if(tempdir == NULL){
2802
perror_plus("mkdtemp");
2803
goto end;
2804
}
2805
2806
if(quit_now){
2807
goto end;
2808
}
2809
2810
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2811
fprintf_plus(stderr, "init_gpgme failed\n");
2812
exitcode = EX_UNAVAILABLE;
2813
goto end;
2814
} else {
2815
gpgme_initialized = true;
2816
}
2817
2818
if(quit_now){
2819
goto end;
2820
}
2821
2822
if(connect_to != NULL){
2823
/* Connect directly, do not use Zeroconf */
2824
/* (Mainly meant for debugging) */
2825
char *address = strrchr(connect_to, ':');
2826
2827
if(address == NULL){
2828
fprintf_plus(stderr, "No colon in address\n");
2829
exitcode = EX_USAGE;
2830
goto end;
2831
}
2832
2833
if(quit_now){
2834
goto end;
2835
}
2836
2837
in_port_t port;
2838
errno = 0;
2839
tmpmax = strtoimax(address+1, &tmp, 10);
2840
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2841
or tmpmax != (in_port_t)tmpmax){
2842
fprintf_plus(stderr, "Bad port number\n");
2843
exitcode = EX_USAGE;
2844
goto end;
2845
}
2846
2847
if(quit_now){
2848
goto end;
2849
}
2850
2851
port = (in_port_t)tmpmax;
2852
*address = '\0';
2853
/* Colon in address indicates IPv6 */
2854
int af;
2855
if(strchr(connect_to, ':') != NULL){
2856
af = AF_INET6;
2857
/* Accept [] around IPv6 address - see RFC 5952 */
2858
if(connect_to[0] == '[' and address[-1] == ']')
2859
{
2860
connect_to++;
2861
address[-1] = '\0';
2862
}
2863
} else {
2864
af = AF_INET;
2865
}
2866
address = connect_to;
2867
2868
if(quit_now){
2869
goto end;
2870
}
2871
2872
while(not quit_now){
2873
ret = start_mandos_communication(address, port, if_index, af,
2874
&mc);
2875
if(quit_now or ret == 0){
2876
break;
2877
}
2878
if(debug){
2879
fprintf_plus(stderr, "Retrying in %d seconds\n",
2880
(int)retry_interval);
2881
}
2882
sleep((unsigned int)retry_interval);
2883
}
2884
2885
if(not quit_now){
2886
exitcode = EXIT_SUCCESS;
2887
}
2888
2889
goto end;
2890
}
2891
2892
if(quit_now){
2893
goto end;
2894
}
2895
2896
{
2897
AvahiServerConfig config;
2898
/* Do not publish any local Zeroconf records */
2899
avahi_server_config_init(&config);
2900
config.publish_hinfo = 0;
2901
config.publish_addresses = 0;
2902
config.publish_workstation = 0;
2903
config.publish_domain = 0;
2904
2905
/* Allocate a new server */
2906
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2907
&config, NULL, NULL, &ret_errno);
2908
2909
/* Free the Avahi configuration data */
2910
avahi_server_config_free(&config);
2911
}
2912
2913
/* Check if creating the Avahi server object succeeded */
2914
if(mc.server == NULL){
2915
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2916
avahi_strerror(ret_errno));
2917
exitcode = EX_UNAVAILABLE;
2918
goto end;
2919
}
2920
2921
if(quit_now){
2922
goto end;
2923
}
2924
2925
/* Create the Avahi service browser */
2926
sb = avahi_s_service_browser_new(mc.server, if_index,
2927
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2928
NULL, 0, browse_callback,
2929
(void *)&mc);
2930
if(sb == NULL){
2931
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2932
avahi_strerror(avahi_server_errno(mc.server)));
2933
exitcode = EX_UNAVAILABLE;
2934
goto end;
2935
}
2936
2937
if(quit_now){
2938
goto end;
2939
}
2940
2941
/* Run the main loop */
2942
2943
if(debug){
2944
fprintf_plus(stderr, "Starting Avahi loop search\n");
2945
}
2946
2947
ret = avahi_loop_with_timeout(simple_poll,
2948
(int)(retry_interval * 1000), &mc);
2949
if(debug){
2950
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2951
(ret == 0) ? "successfully" : "with error");
2952
}
2953
2954
end:
2955
2956
if(debug){
2957
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2958
}
2959
2960
/* Cleanup things */
2961
free(mc.interfaces);
2962
2963
if(sb != NULL)
2964
avahi_s_service_browser_free(sb);
2965
2966
if(mc.server != NULL)
2967
avahi_server_free(mc.server);
2968
2969
if(simple_poll != NULL)
2970
avahi_simple_poll_free(simple_poll);
2971
2972
if(gnutls_initialized){
2973
gnutls_certificate_free_credentials(mc.cred);
2974
gnutls_global_deinit();
2975
gnutls_dh_params_deinit(mc.dh_params);
2976
}
2977
2978
if(gpgme_initialized){
2979
gpgme_release(mc.ctx);
2980
}
2981
2982
/* Cleans up the circular linked list of Mandos servers the client
2983
has seen */
2984
if(mc.current_server != NULL){
2985
mc.current_server->prev->next = NULL;
2986
while(mc.current_server != NULL){
2987
server *next = mc.current_server->next;
2988
#ifdef __GNUC__
2989
#pragma GCC diagnostic push
2990
#pragma GCC diagnostic ignored "-Wcast-qual"
2991
#endif
2992
free((char *)(mc.current_server->ip));
2993
#ifdef __GNUC__
2994
#pragma GCC diagnostic pop
2995
#endif
2996
free(mc.current_server);
2997
mc.current_server = next;
2998
}
2999
}
3000
3001
/* Re-raise privileges */
3002
{
3003
ret_errno = raise_privileges();
3004
if(ret_errno != 0){
3005
errno = ret_errno;
3006
perror_plus("Failed to raise privileges");
3007
} else {
3008
3009
/* Run network hooks */
3010
run_network_hooks("stop", interfaces_hooks != NULL ?
3011
interfaces_hooks : "", delay);
3012
3013
/* Take down the network interfaces which were brought up */
3014
{
3015
char *interface = NULL;
3016
while((interface=argz_next(interfaces_to_take_down,
3017
interfaces_to_take_down_size,
3018
interface))){
3019
ret_errno = take_down_interface(interface);
3020
if(ret_errno != 0){
3021
errno = ret_errno;
3022
perror_plus("Failed to take down interface");
3023
}
3024
}
3025
if(debug and (interfaces_to_take_down == NULL)){
3026
fprintf_plus(stderr, "No interfaces needed to be taken"
3027
" down\n");
3028
}
3029
}
3030
}
3031
3032
ret_errno = lower_privileges_permanently();
3033
if(ret_errno != 0){
3034
errno = ret_errno;
3035
perror_plus("Failed to lower privileges permanently");
3036
}
3037
}
3038
3039
free(interfaces_to_take_down);
3040
free(interfaces_hooks);
3041
3042
/* Removes the GPGME temp directory and all files inside */
3043
if(tempdir != NULL){
3044
struct dirent **direntries = NULL;
3045
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3046
| O_NOFOLLOW
3047
| O_DIRECTORY
3048
| O_PATH));
3049
if(tempdir_fd == -1){
3050
perror_plus("open");
3051
} else {
3052
#ifdef __GLIBC__
3053
#if __GLIBC_PREREQ(2, 15)
3054
int numentries = scandirat(tempdir_fd, ".", &direntries,
3055
notdotentries, alphasort);
3056
#else /* not __GLIBC_PREREQ(2, 15) */
3057
int numentries = scandir(tempdir, &direntries, notdotentries,
3058
alphasort);
3059
#endif /* not __GLIBC_PREREQ(2, 15) */
3060
#else /* not __GLIBC__ */
3061
int numentries = scandir(tempdir, &direntries, notdotentries,
3062
alphasort);
3063
#endif /* not __GLIBC__ */
3064
if(numentries >= 0){
3065
for(int i = 0; i < numentries; i++){
3066
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3067
if(ret == -1){
3068
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3069
" \"%s\", 0): %s\n", tempdir,
3070
direntries[i]->d_name, strerror(errno));
3071
}
3072
free(direntries[i]);
3073
}
3074
3075
/* need to clean even if 0 because man page doesn't specify */
3076
free(direntries);
3077
if(numentries == -1){
3078
perror_plus("scandir");
3079
}
3080
ret = rmdir(tempdir);
3081
if(ret == -1 and errno != ENOENT){
3082
perror_plus("rmdir");
3083
}
3084
}
3085
TEMP_FAILURE_RETRY(close(tempdir_fd));
3086
}
3087
}
3088
3089
if(quit_now){
3090
sigemptyset(&old_sigterm_action.sa_mask);
3091
old_sigterm_action.sa_handler = SIG_DFL;
3092
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3093
&old_sigterm_action,
3094
NULL));
3095
if(ret == -1){
3096
perror_plus("sigaction");
3097
}
3098
do {
3099
ret = raise(signal_received);
3100
} while(ret != 0 and errno == EINTR);
3101
if(ret != 0){
3102
perror_plus("raise");
3103
abort();
3104
}
3105
TEMP_FAILURE_RETRY(pause());
3106
}
3107
3108
return exitcode;
3109
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0