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- Committer: Teddy Hogeborn
- Date: 2016-02-28 20:34:59 UTC
- Revision ID: teddy@recompile.se-20160228203459-81vtqvr96yukyrok
Client: Remove calls to gnutls_global_init and gnutls_global_deinit
* plugins.d/mandos-client.c (init_gnutls_global, main): Don't call
gnutls_global_init or gnutls_global_deinit anymore; these are
unnecessary in GnuTLS 3.3.
* plugins.d/mandos-client.c (init_gnutls_global, main): Don't call
gnutls_global_init or gnutls_global_deinit anymore; these are
unnecessary in GnuTLS 3.3.
- files added:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- plugins.d
- files removed:
- bad-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 © 2008-2016 Teddy Hogeborn
13
* Copyright © 2008-2016 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(), strncpy() */
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(1, 2, 4), 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
if(debug){
529
/* "Use a log level over 10 to enable all debugging options."
530
* - GnuTLS manual
531
*/
532
gnutls_global_set_log_level(11);
533
gnutls_global_set_log_function(debuggnutls);
534
}
535
536
/* OpenPGP credentials */
537
ret = gnutls_certificate_allocate_credentials(&mc->cred);
538
if(ret != GNUTLS_E_SUCCESS){
539
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
540
safer_gnutls_strerror(ret));
541
return -1;
542
}
543
544
if(debug){
545
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
546
" secret key %s as GnuTLS credentials\n",
547
pubkeyfilename,
548
seckeyfilename);
549
}
550
551
ret = gnutls_certificate_set_openpgp_key_file
552
(mc->cred, pubkeyfilename, seckeyfilename,
553
GNUTLS_OPENPGP_FMT_BASE64);
554
if(ret != GNUTLS_E_SUCCESS){
555
fprintf_plus(stderr,
556
"Error[%d] while reading the OpenPGP key pair ('%s',"
557
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
558
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
559
safer_gnutls_strerror(ret));
560
goto globalfail;
561
}
562
563
/* GnuTLS server initialization */
564
ret = gnutls_dh_params_init(&mc->dh_params);
565
if(ret != GNUTLS_E_SUCCESS){
566
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
567
" initialization: %s\n",
568
safer_gnutls_strerror(ret));
569
goto globalfail;
570
}
571
/* If a Diffie-Hellman parameters file was given, try to use it */
572
if(dhparamsfilename != NULL){
573
gnutls_datum_t params = { .data = NULL, .size = 0 };
574
do {
575
int dhpfile = open(dhparamsfilename, O_RDONLY);
576
if(dhpfile == -1){
577
perror_plus("open");
578
dhparamsfilename = NULL;
579
break;
580
}
581
size_t params_capacity = 0;
582
while(true){
583
params_capacity = incbuffer((char **)¶ms.data,
584
(size_t)params.size,
585
(size_t)params_capacity);
586
if(params_capacity == 0){
587
perror_plus("incbuffer");
588
free(params.data);
589
params.data = NULL;
590
dhparamsfilename = NULL;
591
break;
592
}
593
ssize_t bytes_read = read(dhpfile,
594
params.data + params.size,
595
BUFFER_SIZE);
596
/* EOF */
597
if(bytes_read == 0){
598
break;
599
}
600
/* check bytes_read for failure */
601
if(bytes_read < 0){
602
perror_plus("read");
603
free(params.data);
604
params.data = NULL;
605
dhparamsfilename = NULL;
606
break;
607
}
608
params.size += (unsigned int)bytes_read;
609
}
610
if(params.data == NULL){
611
dhparamsfilename = NULL;
612
}
613
if(dhparamsfilename == NULL){
614
break;
615
}
616
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
617
GNUTLS_X509_FMT_PEM);
618
if(ret != GNUTLS_E_SUCCESS){
619
fprintf_plus(stderr, "Failed to parse DH parameters in file"
620
" \"%s\": %s\n", dhparamsfilename,
621
safer_gnutls_strerror(ret));
622
dhparamsfilename = NULL;
623
}
624
} while(false);
625
}
626
if(dhparamsfilename == NULL){
627
if(mc->dh_bits == 0){
628
/* Find out the optimal number of DH bits */
629
/* Try to read the private key file */
630
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
631
do {
632
int secfile = open(seckeyfilename, O_RDONLY);
633
if(secfile == -1){
634
perror_plus("open");
635
break;
636
}
637
size_t buffer_capacity = 0;
638
while(true){
639
buffer_capacity = incbuffer((char **)&buffer.data,
640
(size_t)buffer.size,
641
(size_t)buffer_capacity);
642
if(buffer_capacity == 0){
643
perror_plus("incbuffer");
644
free(buffer.data);
645
buffer.data = NULL;
646
break;
647
}
648
ssize_t bytes_read = read(secfile,
649
buffer.data + buffer.size,
650
BUFFER_SIZE);
651
/* EOF */
652
if(bytes_read == 0){
653
break;
654
}
655
/* check bytes_read for failure */
656
if(bytes_read < 0){
657
perror_plus("read");
658
free(buffer.data);
659
buffer.data = NULL;
660
break;
661
}
662
buffer.size += (unsigned int)bytes_read;
663
}
664
close(secfile);
665
} while(false);
666
/* If successful, use buffer to parse private key */
667
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
668
if(buffer.data != NULL){
669
{
670
gnutls_openpgp_privkey_t privkey = NULL;
671
ret = gnutls_openpgp_privkey_init(&privkey);
672
if(ret != GNUTLS_E_SUCCESS){
673
fprintf_plus(stderr, "Error initializing OpenPGP key"
674
" structure: %s",
675
safer_gnutls_strerror(ret));
676
free(buffer.data);
677
buffer.data = NULL;
678
} else {
679
ret = gnutls_openpgp_privkey_import
680
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
681
if(ret != GNUTLS_E_SUCCESS){
682
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
683
safer_gnutls_strerror(ret));
684
privkey = NULL;
685
}
686
free(buffer.data);
687
buffer.data = NULL;
688
if(privkey != NULL){
689
/* Use private key to suggest an appropriate
690
sec_param */
691
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
692
gnutls_openpgp_privkey_deinit(privkey);
693
if(debug){
694
fprintf_plus(stderr, "This OpenPGP key implies using"
695
" a GnuTLS security parameter \"%s\".\n",
696
safe_string(gnutls_sec_param_get_name
697
(sec_param)));
698
}
699
}
700
}
701
}
702
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
703
/* Err on the side of caution */
704
sec_param = GNUTLS_SEC_PARAM_ULTRA;
705
if(debug){
706
fprintf_plus(stderr, "Falling back to security parameter"
707
" \"%s\"\n",
708
safe_string(gnutls_sec_param_get_name
709
(sec_param)));
710
}
711
}
712
}
713
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
714
if(uret != 0){
715
mc->dh_bits = uret;
716
if(debug){
717
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
718
" implies %u DH bits; using that.\n",
719
safe_string(gnutls_sec_param_get_name
720
(sec_param)),
721
mc->dh_bits);
722
}
723
} else {
724
fprintf_plus(stderr, "Failed to get implied number of DH"
725
" bits for security parameter \"%s\"): %s\n",
726
safe_string(gnutls_sec_param_get_name
727
(sec_param)),
728
safer_gnutls_strerror(ret));
729
goto globalfail;
730
}
731
} else if(debug){
732
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
733
mc->dh_bits);
734
}
735
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
736
if(ret != GNUTLS_E_SUCCESS){
737
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
738
" bits): %s\n", mc->dh_bits,
739
safer_gnutls_strerror(ret));
740
goto globalfail;
741
}
742
}
743
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
744
745
return 0;
746
747
globalfail:
748
749
gnutls_certificate_free_credentials(mc->cred);
750
gnutls_dh_params_deinit(mc->dh_params);
751
return -1;
752
}
753
754
__attribute__((nonnull, warn_unused_result))
755
static int init_gnutls_session(gnutls_session_t *session,
756
mandos_context *mc){
757
int ret;
758
/* GnuTLS session creation */
759
do {
760
ret = gnutls_init(session, GNUTLS_SERVER);
761
if(quit_now){
762
return -1;
763
}
764
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
765
if(ret != GNUTLS_E_SUCCESS){
766
fprintf_plus(stderr,
767
"Error in GnuTLS session initialization: %s\n",
768
safer_gnutls_strerror(ret));
769
}
770
771
{
772
const char *err;
773
do {
774
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
775
if(quit_now){
776
gnutls_deinit(*session);
777
return -1;
778
}
779
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
780
if(ret != GNUTLS_E_SUCCESS){
781
fprintf_plus(stderr, "Syntax error at: %s\n", err);
782
fprintf_plus(stderr, "GnuTLS error: %s\n",
783
safer_gnutls_strerror(ret));
784
gnutls_deinit(*session);
785
return -1;
786
}
787
}
788
789
do {
790
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
791
mc->cred);
792
if(quit_now){
793
gnutls_deinit(*session);
794
return -1;
795
}
796
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
797
if(ret != GNUTLS_E_SUCCESS){
798
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
799
safer_gnutls_strerror(ret));
800
gnutls_deinit(*session);
801
return -1;
802
}
803
804
/* ignore client certificate if any. */
805
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
806
807
return 0;
808
}
809
810
/* Avahi log function callback */
811
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
812
__attribute__((unused)) const char *txt){}
813
814
/* Set effective uid to 0, return errno */
815
__attribute__((warn_unused_result))
816
error_t raise_privileges(void){
817
error_t old_errno = errno;
818
error_t ret_errno = 0;
819
if(seteuid(0) == -1){
820
ret_errno = errno;
821
}
822
errno = old_errno;
823
return ret_errno;
824
}
825
826
/* Set effective and real user ID to 0. Return errno. */
827
__attribute__((warn_unused_result))
828
error_t raise_privileges_permanently(void){
829
error_t old_errno = errno;
830
error_t ret_errno = raise_privileges();
831
if(ret_errno != 0){
832
errno = old_errno;
833
return ret_errno;
834
}
835
if(setuid(0) == -1){
836
ret_errno = errno;
837
}
838
errno = old_errno;
839
return ret_errno;
840
}
841
842
/* Set effective user ID to unprivileged saved user ID */
843
__attribute__((warn_unused_result))
844
error_t lower_privileges(void){
845
error_t old_errno = errno;
846
error_t ret_errno = 0;
847
if(seteuid(uid) == -1){
848
ret_errno = errno;
849
}
850
errno = old_errno;
851
return ret_errno;
852
}
853
854
/* Lower privileges permanently */
855
__attribute__((warn_unused_result))
856
error_t lower_privileges_permanently(void){
857
error_t old_errno = errno;
858
error_t ret_errno = 0;
859
if(setuid(uid) == -1){
860
ret_errno = errno;
861
}
862
errno = old_errno;
863
return ret_errno;
864
}
865
866
/* Helper function to add_local_route() and delete_local_route() */
867
__attribute__((nonnull, warn_unused_result))
868
static bool add_delete_local_route(const bool add,
869
const char *address,
870
AvahiIfIndex if_index){
871
int ret;
872
char helper[] = "mandos-client-iprouteadddel";
873
char add_arg[] = "add";
874
char delete_arg[] = "delete";
875
char debug_flag[] = "--debug";
876
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
877
if(pluginhelperdir == NULL){
878
if(debug){
879
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
880
" variable not set; cannot run helper\n");
881
}
882
return false;
883
}
884
885
char interface[IF_NAMESIZE];
886
if(if_indextoname((unsigned int)if_index, interface) == NULL){
887
perror_plus("if_indextoname");
888
return false;
889
}
890
891
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
892
if(devnull == -1){
893
perror_plus("open(\"/dev/null\", O_RDONLY)");
894
return false;
895
}
896
pid_t pid = fork();
897
if(pid == 0){
898
/* Child */
899
/* Raise privileges */
900
errno = raise_privileges_permanently();
901
if(errno != 0){
902
perror_plus("Failed to raise privileges");
903
/* _exit(EX_NOPERM); */
904
} else {
905
/* Set group */
906
errno = 0;
907
ret = setgid(0);
908
if(ret == -1){
909
perror_plus("setgid");
910
_exit(EX_NOPERM);
911
}
912
/* Reset supplementary groups */
913
errno = 0;
914
ret = setgroups(0, NULL);
915
if(ret == -1){
916
perror_plus("setgroups");
917
_exit(EX_NOPERM);
918
}
919
}
920
ret = dup2(devnull, STDIN_FILENO);
921
if(ret == -1){
922
perror_plus("dup2(devnull, STDIN_FILENO)");
923
_exit(EX_OSERR);
924
}
925
ret = close(devnull);
926
if(ret == -1){
927
perror_plus("close");
928
_exit(EX_OSERR);
929
}
930
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
931
if(ret == -1){
932
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
933
_exit(EX_OSERR);
934
}
935
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
936
O_RDONLY
937
| O_DIRECTORY
938
| O_PATH
939
| O_CLOEXEC));
940
if(helperdir_fd == -1){
941
perror_plus("open");
942
_exit(EX_UNAVAILABLE);
943
}
944
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
945
helper, O_RDONLY));
946
if(helper_fd == -1){
947
perror_plus("openat");
948
close(helperdir_fd);
949
_exit(EX_UNAVAILABLE);
950
}
951
close(helperdir_fd);
952
#ifdef __GNUC__
953
#pragma GCC diagnostic push
954
#pragma GCC diagnostic ignored "-Wcast-qual"
955
#endif
956
if(fexecve(helper_fd, (char *const [])
957
{ helper, add ? add_arg : delete_arg, (char *)address,
958
interface, debug ? debug_flag : NULL, NULL },
959
environ) == -1){
960
#ifdef __GNUC__
961
#pragma GCC diagnostic pop
962
#endif
963
perror_plus("fexecve");
964
_exit(EXIT_FAILURE);
965
}
966
}
967
if(pid == -1){
968
perror_plus("fork");
969
return false;
970
}
971
int status;
972
pid_t pret = -1;
973
errno = 0;
974
do {
975
pret = waitpid(pid, &status, 0);
976
if(pret == -1 and errno == EINTR and quit_now){
977
int errno_raising = 0;
978
if((errno = raise_privileges()) != 0){
979
errno_raising = errno;
980
perror_plus("Failed to raise privileges in order to"
981
" kill helper program");
982
}
983
if(kill(pid, SIGTERM) == -1){
984
perror_plus("kill");
985
}
986
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
987
perror_plus("Failed to lower privileges after killing"
988
" helper program");
989
}
990
return false;
991
}
992
} while(pret == -1 and errno == EINTR);
993
if(pret == -1){
994
perror_plus("waitpid");
995
return false;
996
}
997
if(WIFEXITED(status)){
998
if(WEXITSTATUS(status) != 0){
999
fprintf_plus(stderr, "Error: iprouteadddel exited"
1000
" with status %d\n", WEXITSTATUS(status));
1001
return false;
1002
}
1003
return true;
1004
}
1005
if(WIFSIGNALED(status)){
1006
fprintf_plus(stderr, "Error: iprouteadddel died by"
1007
" signal %d\n", WTERMSIG(status));
1008
return false;
1009
}
1010
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1011
return false;
1012
}
1013
1014
__attribute__((nonnull, warn_unused_result))
1015
static bool add_local_route(const char *address,
1016
AvahiIfIndex if_index){
1017
if(debug){
1018
fprintf_plus(stderr, "Adding route to %s\n", address);
1019
}
1020
return add_delete_local_route(true, address, if_index);
1021
}
1022
1023
__attribute__((nonnull, warn_unused_result))
1024
static bool delete_local_route(const char *address,
1025
AvahiIfIndex if_index){
1026
if(debug){
1027
fprintf_plus(stderr, "Removing route to %s\n", address);
1028
}
1029
return add_delete_local_route(false, address, if_index);
1030
}
1031
1032
/* Called when a Mandos server is found */
1033
__attribute__((nonnull, warn_unused_result))
1034
static int start_mandos_communication(const char *ip, in_port_t port,
1035
AvahiIfIndex if_index,
1036
int af, mandos_context *mc){
1037
int ret, tcp_sd = -1;
1038
ssize_t sret;
1039
struct sockaddr_storage to;
1040
char *buffer = NULL;
1041
char *decrypted_buffer = NULL;
1042
size_t buffer_length = 0;
1043
size_t buffer_capacity = 0;
1044
size_t written;
1045
int retval = -1;
1046
gnutls_session_t session;
1047
int pf; /* Protocol family */
1048
bool route_added = false;
1049
1050
errno = 0;
1051
1052
if(quit_now){
1053
errno = EINTR;
1054
return -1;
1055
}
1056
1057
switch(af){
1058
case AF_INET6:
1059
pf = PF_INET6;
1060
break;
1061
case AF_INET:
1062
pf = PF_INET;
1063
break;
1064
default:
1065
fprintf_plus(stderr, "Bad address family: %d\n", af);
1066
errno = EINVAL;
1067
return -1;
1068
}
1069
1070
/* If the interface is specified and we have a list of interfaces */
1071
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1072
/* Check if the interface is one of the interfaces we are using */
1073
bool match = false;
1074
{
1075
char *interface = NULL;
1076
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1077
interface))){
1078
if(if_nametoindex(interface) == (unsigned int)if_index){
1079
match = true;
1080
break;
1081
}
1082
}
1083
}
1084
if(not match){
1085
/* This interface does not match any in the list, so we don't
1086
connect to the server */
1087
if(debug){
1088
char interface[IF_NAMESIZE];
1089
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1090
perror_plus("if_indextoname");
1091
} else {
1092
fprintf_plus(stderr, "Skipping server on non-used interface"
1093
" \"%s\"\n",
1094
if_indextoname((unsigned int)if_index,
1095
interface));
1096
}
1097
}
1098
return -1;
1099
}
1100
}
1101
1102
ret = init_gnutls_session(&session, mc);
1103
if(ret != 0){
1104
return -1;
1105
}
1106
1107
if(debug){
1108
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1109
PRIuMAX "\n", ip, (uintmax_t)port);
1110
}
1111
1112
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1113
if(tcp_sd < 0){
1114
int e = errno;
1115
perror_plus("socket");
1116
errno = e;
1117
goto mandos_end;
1118
}
1119
1120
if(quit_now){
1121
errno = EINTR;
1122
goto mandos_end;
1123
}
1124
1125
if(af == AF_INET6){
1126
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1127
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1128
ret = inet_pton(af, ip, &to6->sin6_addr);
1129
} else { /* IPv4 */
1130
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1131
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1132
ret = inet_pton(af, ip, &to4->sin_addr);
1133
}
1134
if(ret < 0 ){
1135
int e = errno;
1136
perror_plus("inet_pton");
1137
errno = e;
1138
goto mandos_end;
1139
}
1140
if(ret == 0){
1141
int e = errno;
1142
fprintf_plus(stderr, "Bad address: %s\n", ip);
1143
errno = e;
1144
goto mandos_end;
1145
}
1146
if(af == AF_INET6){
1147
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1148
if(IN6_IS_ADDR_LINKLOCAL
1149
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1150
if(if_index == AVAHI_IF_UNSPEC){
1151
fprintf_plus(stderr, "An IPv6 link-local address is"
1152
" incomplete without a network interface\n");
1153
errno = EINVAL;
1154
goto mandos_end;
1155
}
1156
/* Set the network interface number as scope */
1157
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1158
}
1159
} else {
1160
((struct sockaddr_in *)&to)->sin_port = htons(port);
1161
}
1162
1163
if(quit_now){
1164
errno = EINTR;
1165
goto mandos_end;
1166
}
1167
1168
if(debug){
1169
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1170
char interface[IF_NAMESIZE];
1171
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1172
perror_plus("if_indextoname");
1173
} else {
1174
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1175
"\n", ip, interface, (uintmax_t)port);
1176
}
1177
} else {
1178
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1179
ip, (uintmax_t)port);
1180
}
1181
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1182
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1183
if(af == AF_INET6){
1184
ret = getnameinfo((struct sockaddr *)&to,
1185
sizeof(struct sockaddr_in6),
1186
addrstr, sizeof(addrstr), NULL, 0,
1187
NI_NUMERICHOST);
1188
} else {
1189
ret = getnameinfo((struct sockaddr *)&to,
1190
sizeof(struct sockaddr_in),
1191
addrstr, sizeof(addrstr), NULL, 0,
1192
NI_NUMERICHOST);
1193
}
1194
if(ret == EAI_SYSTEM){
1195
perror_plus("getnameinfo");
1196
} else if(ret != 0) {
1197
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1198
} else if(strcmp(addrstr, ip) != 0){
1199
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1200
}
1201
}
1202
1203
if(quit_now){
1204
errno = EINTR;
1205
goto mandos_end;
1206
}
1207
1208
while(true){
1209
if(af == AF_INET6){
1210
ret = connect(tcp_sd, (struct sockaddr *)&to,
1211
sizeof(struct sockaddr_in6));
1212
} else {
1213
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1214
sizeof(struct sockaddr_in));
1215
}
1216
if(ret < 0){
1217
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1218
and if_index != AVAHI_IF_UNSPEC
1219
and connect_to == NULL
1220
and not route_added and
1221
((af == AF_INET6 and not
1222
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1223
&to)->sin6_addr)))
1224
or (af == AF_INET and
1225
/* Not a a IPv4LL address */
1226
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1227
& 0xFFFF0000L) != 0xA9FE0000L))){
1228
/* Work around Avahi bug - Avahi does not announce link-local
1229
addresses if it has a global address, so local hosts with
1230
*only* a link-local address (e.g. Mandos clients) cannot
1231
connect to a Mandos server announced by Avahi on a server
1232
host with a global address. Work around this by retrying
1233
with an explicit route added with the server's address.
1234
1235
Avahi bug reference:
1236
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1237
https://bugs.debian.org/587961
1238
*/
1239
if(debug){
1240
fprintf_plus(stderr, "Mandos server unreachable, trying"
1241
" direct route\n");
1242
}
1243
int e = errno;
1244
route_added = add_local_route(ip, if_index);
1245
if(route_added){
1246
continue;
1247
}
1248
errno = e;
1249
}
1250
if(errno != ECONNREFUSED or debug){
1251
int e = errno;
1252
perror_plus("connect");
1253
errno = e;
1254
}
1255
goto mandos_end;
1256
}
1257
1258
if(quit_now){
1259
errno = EINTR;
1260
goto mandos_end;
1261
}
1262
break;
1263
}
1264
1265
const char *out = mandos_protocol_version;
1266
written = 0;
1267
while(true){
1268
size_t out_size = strlen(out);
1269
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1270
out_size - written));
1271
if(ret == -1){
1272
int e = errno;
1273
perror_plus("write");
1274
errno = e;
1275
goto mandos_end;
1276
}
1277
written += (size_t)ret;
1278
if(written < out_size){
1279
continue;
1280
} else {
1281
if(out == mandos_protocol_version){
1282
written = 0;
1283
out = "\r\n";
1284
} else {
1285
break;
1286
}
1287
}
1288
1289
if(quit_now){
1290
errno = EINTR;
1291
goto mandos_end;
1292
}
1293
}
1294
1295
if(debug){
1296
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1297
}
1298
1299
if(quit_now){
1300
errno = EINTR;
1301
goto mandos_end;
1302
}
1303
1304
/* This casting via intptr_t is to eliminate warning about casting
1305
an int to a pointer type. This is exactly how the GnuTLS Guile
1306
function "set-session-transport-fd!" does it. */
1307
gnutls_transport_set_ptr(session,
1308
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1309
1310
if(quit_now){
1311
errno = EINTR;
1312
goto mandos_end;
1313
}
1314
1315
do {
1316
ret = gnutls_handshake(session);
1317
if(quit_now){
1318
errno = EINTR;
1319
goto mandos_end;
1320
}
1321
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1322
1323
if(ret != GNUTLS_E_SUCCESS){
1324
if(debug){
1325
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
1326
gnutls_perror(ret);
1327
}
1328
errno = EPROTO;
1329
goto mandos_end;
1330
}
1331
1332
/* Read OpenPGP packet that contains the wanted password */
1333
1334
if(debug){
1335
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1336
" %s\n", ip);
1337
}
1338
1339
while(true){
1340
1341
if(quit_now){
1342
errno = EINTR;
1343
goto mandos_end;
1344
}
1345
1346
buffer_capacity = incbuffer(&buffer, buffer_length,
1347
buffer_capacity);
1348
if(buffer_capacity == 0){
1349
int e = errno;
1350
perror_plus("incbuffer");
1351
errno = e;
1352
goto mandos_end;
1353
}
1354
1355
if(quit_now){
1356
errno = EINTR;
1357
goto mandos_end;
1358
}
1359
1360
sret = gnutls_record_recv(session, buffer+buffer_length,
1361
BUFFER_SIZE);
1362
if(sret == 0){
1363
break;
1364
}
1365
if(sret < 0){
1366
switch(sret){
1367
case GNUTLS_E_INTERRUPTED:
1368
case GNUTLS_E_AGAIN:
1369
break;
1370
case GNUTLS_E_REHANDSHAKE:
1371
do {
1372
ret = gnutls_handshake(session);
1373
1374
if(quit_now){
1375
errno = EINTR;
1376
goto mandos_end;
1377
}
1378
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1379
if(ret < 0){
1380
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1381
"***\n");
1382
gnutls_perror(ret);
1383
errno = EPROTO;
1384
goto mandos_end;
1385
}
1386
break;
1387
default:
1388
fprintf_plus(stderr, "Unknown error while reading data from"
1389
" encrypted session with Mandos server\n");
1390
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1391
errno = EIO;
1392
goto mandos_end;
1393
}
1394
} else {
1395
buffer_length += (size_t) sret;
1396
}
1397
}
1398
1399
if(debug){
1400
fprintf_plus(stderr, "Closing TLS session\n");
1401
}
1402
1403
if(quit_now){
1404
errno = EINTR;
1405
goto mandos_end;
1406
}
1407
1408
do {
1409
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1410
if(quit_now){
1411
errno = EINTR;
1412
goto mandos_end;
1413
}
1414
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1415
1416
if(buffer_length > 0){
1417
ssize_t decrypted_buffer_size;
1418
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1419
&decrypted_buffer, mc);
1420
if(decrypted_buffer_size >= 0){
1421
1422
written = 0;
1423
while(written < (size_t) decrypted_buffer_size){
1424
if(quit_now){
1425
errno = EINTR;
1426
goto mandos_end;
1427
}
1428
1429
ret = (int)fwrite(decrypted_buffer + written, 1,
1430
(size_t)decrypted_buffer_size - written,
1431
stdout);
1432
if(ret == 0 and ferror(stdout)){
1433
int e = errno;
1434
if(debug){
1435
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1436
strerror(errno));
1437
}
1438
errno = e;
1439
goto mandos_end;
1440
}
1441
written += (size_t)ret;
1442
}
1443
retval = 0;
1444
}
1445
}
1446
1447
/* Shutdown procedure */
1448
1449
mandos_end:
1450
{
1451
if(route_added){
1452
if(not delete_local_route(ip, if_index)){
1453
fprintf_plus(stderr, "Failed to delete local route to %s on"
1454
" interface %d", ip, if_index);
1455
}
1456
}
1457
int e = errno;
1458
free(decrypted_buffer);
1459
free(buffer);
1460
if(tcp_sd >= 0){
1461
ret = close(tcp_sd);
1462
}
1463
if(ret == -1){
1464
if(e == 0){
1465
e = errno;
1466
}
1467
perror_plus("close");
1468
}
1469
gnutls_deinit(session);
1470
errno = e;
1471
if(quit_now){
1472
errno = EINTR;
1473
retval = -1;
1474
}
1475
}
1476
return retval;
1477
}
1478
1479
__attribute__((nonnull))
1480
static void resolve_callback(AvahiSServiceResolver *r,
1481
AvahiIfIndex interface,
1482
AvahiProtocol proto,
1483
AvahiResolverEvent event,
1484
const char *name,
1485
const char *type,
1486
const char *domain,
1487
const char *host_name,
1488
const AvahiAddress *address,
1489
uint16_t port,
1490
AVAHI_GCC_UNUSED AvahiStringList *txt,
1491
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1492
flags,
1493
void *mc){
1494
if(r == NULL){
1495
return;
1496
}
1497
1498
/* Called whenever a service has been resolved successfully or
1499
timed out */
1500
1501
if(quit_now){
1502
avahi_s_service_resolver_free(r);
1503
return;
1504
}
1505
1506
switch(event){
1507
default:
1508
case AVAHI_RESOLVER_FAILURE:
1509
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1510
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1511
domain,
1512
avahi_strerror(avahi_server_errno
1513
(((mandos_context*)mc)->server)));
1514
break;
1515
1516
case AVAHI_RESOLVER_FOUND:
1517
{
1518
char ip[AVAHI_ADDRESS_STR_MAX];
1519
avahi_address_snprint(ip, sizeof(ip), address);
1520
if(debug){
1521
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1522
PRIdMAX ") on port %" PRIu16 "\n", name,
1523
host_name, ip, (intmax_t)interface, port);
1524
}
1525
int ret = start_mandos_communication(ip, (in_port_t)port,
1526
interface,
1527
avahi_proto_to_af(proto),
1528
mc);
1529
if(ret == 0){
1530
avahi_simple_poll_quit(simple_poll);
1531
} else {
1532
if(not add_server(ip, (in_port_t)port, interface,
1533
avahi_proto_to_af(proto),
1534
&((mandos_context*)mc)->current_server)){
1535
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1536
" list\n", name);
1537
}
1538
}
1539
}
1540
}
1541
avahi_s_service_resolver_free(r);
1542
}
1543
1544
static void browse_callback(AvahiSServiceBrowser *b,
1545
AvahiIfIndex interface,
1546
AvahiProtocol protocol,
1547
AvahiBrowserEvent event,
1548
const char *name,
1549
const char *type,
1550
const char *domain,
1551
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1552
flags,
1553
void *mc){
1554
if(b == NULL){
1555
return;
1556
}
1557
1558
/* Called whenever a new services becomes available on the LAN or
1559
is removed from the LAN */
1560
1561
if(quit_now){
1562
return;
1563
}
1564
1565
switch(event){
1566
default:
1567
case AVAHI_BROWSER_FAILURE:
1568
1569
fprintf_plus(stderr, "(Avahi browser) %s\n",
1570
avahi_strerror(avahi_server_errno
1571
(((mandos_context*)mc)->server)));
1572
avahi_simple_poll_quit(simple_poll);
1573
return;
1574
1575
case AVAHI_BROWSER_NEW:
1576
/* We ignore the returned Avahi resolver object. In the callback
1577
function we free it. If the Avahi server is terminated before
1578
the callback function is called the Avahi server will free the
1579
resolver for us. */
1580
1581
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1582
interface, protocol, name, type,
1583
domain, protocol, 0,
1584
resolve_callback, mc) == NULL)
1585
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1586
" %s\n", name,
1587
avahi_strerror(avahi_server_errno
1588
(((mandos_context*)mc)->server)));
1589
break;
1590
1591
case AVAHI_BROWSER_REMOVE:
1592
break;
1593
1594
case AVAHI_BROWSER_ALL_FOR_NOW:
1595
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1596
if(debug){
1597
fprintf_plus(stderr, "No Mandos server found, still"
1598
" searching...\n");
1599
}
1600
break;
1601
}
1602
}
1603
1604
/* Signal handler that stops main loop after SIGTERM */
1605
static void handle_sigterm(int sig){
1606
if(quit_now){
1607
return;
1608
}
1609
quit_now = 1;
1610
signal_received = sig;
1611
int old_errno = errno;
1612
/* set main loop to exit */
1613
if(simple_poll != NULL){
1614
avahi_simple_poll_quit(simple_poll);
1615
}
1616
errno = old_errno;
1617
}
1618
1619
__attribute__((nonnull, warn_unused_result))
1620
bool get_flags(const char *ifname, struct ifreq *ifr){
1621
int ret;
1622
error_t ret_errno;
1623
1624
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1625
if(s < 0){
1626
ret_errno = errno;
1627
perror_plus("socket");
1628
errno = ret_errno;
1629
return false;
1630
}
1631
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1632
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1633
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1634
if(ret == -1){
1635
if(debug){
1636
ret_errno = errno;
1637
perror_plus("ioctl SIOCGIFFLAGS");
1638
errno = ret_errno;
1639
}
1640
return false;
1641
}
1642
return true;
1643
}
1644
1645
__attribute__((nonnull, warn_unused_result))
1646
bool good_flags(const char *ifname, const struct ifreq *ifr){
1647
1648
/* Reject the loopback device */
1649
if(ifr->ifr_flags & IFF_LOOPBACK){
1650
if(debug){
1651
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1652
ifname);
1653
}
1654
return false;
1655
}
1656
/* Accept point-to-point devices only if connect_to is specified */
1657
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1658
if(debug){
1659
fprintf_plus(stderr, "Accepting point-to-point interface"
1660
" \"%s\"\n", ifname);
1661
}
1662
return true;
1663
}
1664
/* Otherwise, reject non-broadcast-capable devices */
1665
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1666
if(debug){
1667
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1668
" \"%s\"\n", ifname);
1669
}
1670
return false;
1671
}
1672
/* Reject non-ARP interfaces (including dummy interfaces) */
1673
if(ifr->ifr_flags & IFF_NOARP){
1674
if(debug){
1675
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1676
ifname);
1677
}
1678
return false;
1679
}
1680
1681
/* Accept this device */
1682
if(debug){
1683
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1684
}
1685
return true;
1686
}
1687
1688
/*
1689
* This function determines if a directory entry in /sys/class/net
1690
* corresponds to an acceptable network device.
1691
* (This function is passed to scandir(3) as a filter function.)
1692
*/
1693
__attribute__((nonnull, warn_unused_result))
1694
int good_interface(const struct dirent *if_entry){
1695
if(if_entry->d_name[0] == '.'){
1696
return 0;
1697
}
1698
1699
struct ifreq ifr;
1700
if(not get_flags(if_entry->d_name, &ifr)){
1701
if(debug){
1702
fprintf_plus(stderr, "Failed to get flags for interface "
1703
"\"%s\"\n", if_entry->d_name);
1704
}
1705
return 0;
1706
}
1707
1708
if(not good_flags(if_entry->d_name, &ifr)){
1709
return 0;
1710
}
1711
return 1;
1712
}
1713
1714
/*
1715
* This function determines if a network interface is up.
1716
*/
1717
__attribute__((nonnull, warn_unused_result))
1718
bool interface_is_up(const char *interface){
1719
struct ifreq ifr;
1720
if(not get_flags(interface, &ifr)){
1721
if(debug){
1722
fprintf_plus(stderr, "Failed to get flags for interface "
1723
"\"%s\"\n", interface);
1724
}
1725
return false;
1726
}
1727
1728
return (bool)(ifr.ifr_flags & IFF_UP);
1729
}
1730
1731
/*
1732
* This function determines if a network interface is running
1733
*/
1734
__attribute__((nonnull, warn_unused_result))
1735
bool interface_is_running(const char *interface){
1736
struct ifreq ifr;
1737
if(not get_flags(interface, &ifr)){
1738
if(debug){
1739
fprintf_plus(stderr, "Failed to get flags for interface "
1740
"\"%s\"\n", interface);
1741
}
1742
return false;
1743
}
1744
1745
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1746
}
1747
1748
__attribute__((nonnull, pure, warn_unused_result))
1749
int notdotentries(const struct dirent *direntry){
1750
/* Skip "." and ".." */
1751
if(direntry->d_name[0] == '.'
1752
and (direntry->d_name[1] == '\0'
1753
or (direntry->d_name[1] == '.'
1754
and direntry->d_name[2] == '\0'))){
1755
return 0;
1756
}
1757
return 1;
1758
}
1759
1760
/* Is this directory entry a runnable program? */
1761
__attribute__((nonnull, warn_unused_result))
1762
int runnable_hook(const struct dirent *direntry){
1763
int ret;
1764
size_t sret;
1765
struct stat st;
1766
1767
if((direntry->d_name)[0] == '\0'){
1768
/* Empty name? */
1769
return 0;
1770
}
1771
1772
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1773
"abcdefghijklmnopqrstuvwxyz"
1774
"0123456789"
1775
"_.-");
1776
if((direntry->d_name)[sret] != '\0'){
1777
/* Contains non-allowed characters */
1778
if(debug){
1779
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1780
direntry->d_name);
1781
}
1782
return 0;
1783
}
1784
1785
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1786
if(ret == -1){
1787
if(debug){
1788
perror_plus("Could not stat hook");
1789
}
1790
return 0;
1791
}
1792
if(not (S_ISREG(st.st_mode))){
1793
/* Not a regular file */
1794
if(debug){
1795
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1796
direntry->d_name);
1797
}
1798
return 0;
1799
}
1800
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1801
/* Not executable */
1802
if(debug){
1803
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1804
direntry->d_name);
1805
}
1806
return 0;
1807
}
1808
if(debug){
1809
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1810
direntry->d_name);
1811
}
1812
return 1;
1813
}
1814
1815
__attribute__((nonnull, warn_unused_result))
1816
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1817
mandos_context *mc){
1818
int ret;
1819
struct timespec now;
1820
struct timespec waited_time;
1821
intmax_t block_time;
1822
1823
while(true){
1824
if(mc->current_server == NULL){
1825
if(debug){
1826
fprintf_plus(stderr, "Wait until first server is found."
1827
" No timeout!\n");
1828
}
1829
ret = avahi_simple_poll_iterate(s, -1);
1830
} else {
1831
if(debug){
1832
fprintf_plus(stderr, "Check current_server if we should run"
1833
" it, or wait\n");
1834
}
1835
/* the current time */
1836
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1837
if(ret == -1){
1838
perror_plus("clock_gettime");
1839
return -1;
1840
}
1841
/* Calculating in ms how long time between now and server
1842
who we visted longest time ago. Now - last seen. */
1843
waited_time.tv_sec = (now.tv_sec
1844
- mc->current_server->last_seen.tv_sec);
1845
waited_time.tv_nsec = (now.tv_nsec
1846
- mc->current_server->last_seen.tv_nsec);
1847
/* total time is 10s/10,000ms.
1848
Converting to s from ms by dividing by 1,000,
1849
and ns to ms by dividing by 1,000,000. */
1850
block_time = ((retry_interval
1851
- ((intmax_t)waited_time.tv_sec * 1000))
1852
- ((intmax_t)waited_time.tv_nsec / 1000000));
1853
1854
if(debug){
1855
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1856
block_time);
1857
}
1858
1859
if(block_time <= 0){
1860
ret = start_mandos_communication(mc->current_server->ip,
1861
mc->current_server->port,
1862
mc->current_server->if_index,
1863
mc->current_server->af, mc);
1864
if(ret == 0){
1865
avahi_simple_poll_quit(s);
1866
return 0;
1867
}
1868
ret = clock_gettime(CLOCK_MONOTONIC,
1869
&mc->current_server->last_seen);
1870
if(ret == -1){
1871
perror_plus("clock_gettime");
1872
return -1;
1873
}
1874
mc->current_server = mc->current_server->next;
1875
block_time = 0; /* Call avahi to find new Mandos
1876
servers, but don't block */
1877
}
1878
1879
ret = avahi_simple_poll_iterate(s, (int)block_time);
1880
}
1881
if(ret != 0){
1882
if(ret > 0 or errno != EINTR){
1883
return (ret != 1) ? ret : 0;
1884
}
1885
}
1886
}
1887
}
1888
1889
__attribute__((nonnull))
1890
void run_network_hooks(const char *mode, const char *interface,
1891
const float delay){
1892
struct dirent **direntries = NULL;
1893
if(hookdir_fd == -1){
1894
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1895
| O_CLOEXEC);
1896
if(hookdir_fd == -1){
1897
if(errno == ENOENT){
1898
if(debug){
1899
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1900
" found\n", hookdir);
1901
}
1902
} else {
1903
perror_plus("open");
1904
}
1905
return;
1906
}
1907
}
1908
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1909
runnable_hook, alphasort);
1910
if(numhooks == -1){
1911
perror_plus("scandir");
1912
return;
1913
}
1914
struct dirent *direntry;
1915
int ret;
1916
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1917
if(devnull == -1){
1918
perror_plus("open(\"/dev/null\", O_RDONLY)");
1919
return;
1920
}
1921
for(int i = 0; i < numhooks; i++){
1922
direntry = direntries[i];
1923
if(debug){
1924
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1925
direntry->d_name);
1926
}
1927
pid_t hook_pid = fork();
1928
if(hook_pid == 0){
1929
/* Child */
1930
/* Raise privileges */
1931
errno = raise_privileges_permanently();
1932
if(errno != 0){
1933
perror_plus("Failed to raise privileges");
1934
_exit(EX_NOPERM);
1935
}
1936
/* Set group */
1937
errno = 0;
1938
ret = setgid(0);
1939
if(ret == -1){
1940
perror_plus("setgid");
1941
_exit(EX_NOPERM);
1942
}
1943
/* Reset supplementary groups */
1944
errno = 0;
1945
ret = setgroups(0, NULL);
1946
if(ret == -1){
1947
perror_plus("setgroups");
1948
_exit(EX_NOPERM);
1949
}
1950
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1951
if(ret == -1){
1952
perror_plus("setenv");
1953
_exit(EX_OSERR);
1954
}
1955
ret = setenv("DEVICE", interface, 1);
1956
if(ret == -1){
1957
perror_plus("setenv");
1958
_exit(EX_OSERR);
1959
}
1960
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1961
if(ret == -1){
1962
perror_plus("setenv");
1963
_exit(EX_OSERR);
1964
}
1965
ret = setenv("MODE", mode, 1);
1966
if(ret == -1){
1967
perror_plus("setenv");
1968
_exit(EX_OSERR);
1969
}
1970
char *delaystring;
1971
ret = asprintf(&delaystring, "%f", (double)delay);
1972
if(ret == -1){
1973
perror_plus("asprintf");
1974
_exit(EX_OSERR);
1975
}
1976
ret = setenv("DELAY", delaystring, 1);
1977
if(ret == -1){
1978
free(delaystring);
1979
perror_plus("setenv");
1980
_exit(EX_OSERR);
1981
}
1982
free(delaystring);
1983
if(connect_to != NULL){
1984
ret = setenv("CONNECT", connect_to, 1);
1985
if(ret == -1){
1986
perror_plus("setenv");
1987
_exit(EX_OSERR);
1988
}
1989
}
1990
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
1991
direntry->d_name,
1992
O_RDONLY));
1993
if(hook_fd == -1){
1994
perror_plus("openat");
1995
_exit(EXIT_FAILURE);
1996
}
1997
if(close(hookdir_fd) == -1){
1998
perror_plus("close");
1999
_exit(EXIT_FAILURE);
2000
}
2001
ret = dup2(devnull, STDIN_FILENO);
2002
if(ret == -1){
2003
perror_plus("dup2(devnull, STDIN_FILENO)");
2004
_exit(EX_OSERR);
2005
}
2006
ret = close(devnull);
2007
if(ret == -1){
2008
perror_plus("close");
2009
_exit(EX_OSERR);
2010
}
2011
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2012
if(ret == -1){
2013
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2014
_exit(EX_OSERR);
2015
}
2016
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2017
environ) == -1){
2018
perror_plus("fexecve");
2019
_exit(EXIT_FAILURE);
2020
}
2021
} else {
2022
if(hook_pid == -1){
2023
perror_plus("fork");
2024
free(direntry);
2025
continue;
2026
}
2027
int status;
2028
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2029
perror_plus("waitpid");
2030
free(direntry);
2031
continue;
2032
}
2033
if(WIFEXITED(status)){
2034
if(WEXITSTATUS(status) != 0){
2035
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2036
" with status %d\n", direntry->d_name,
2037
WEXITSTATUS(status));
2038
free(direntry);
2039
continue;
2040
}
2041
} else if(WIFSIGNALED(status)){
2042
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2043
" signal %d\n", direntry->d_name,
2044
WTERMSIG(status));
2045
free(direntry);
2046
continue;
2047
} else {
2048
fprintf_plus(stderr, "Warning: network hook \"%s\""
2049
" crashed\n", direntry->d_name);
2050
free(direntry);
2051
continue;
2052
}
2053
}
2054
if(debug){
2055
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2056
direntry->d_name);
2057
}
2058
free(direntry);
2059
}
2060
free(direntries);
2061
if(close(hookdir_fd) == -1){
2062
perror_plus("close");
2063
} else {
2064
hookdir_fd = -1;
2065
}
2066
close(devnull);
2067
}
2068
2069
__attribute__((nonnull, warn_unused_result))
2070
error_t bring_up_interface(const char *const interface,
2071
const float delay){
2072
error_t old_errno = errno;
2073
int ret;
2074
struct ifreq network;
2075
unsigned int if_index = if_nametoindex(interface);
2076
if(if_index == 0){
2077
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2078
errno = old_errno;
2079
return ENXIO;
2080
}
2081
2082
if(quit_now){
2083
errno = old_errno;
2084
return EINTR;
2085
}
2086
2087
if(not interface_is_up(interface)){
2088
error_t ret_errno = 0, ioctl_errno = 0;
2089
if(not get_flags(interface, &network)){
2090
ret_errno = errno;
2091
fprintf_plus(stderr, "Failed to get flags for interface "
2092
"\"%s\"\n", interface);
2093
errno = old_errno;
2094
return ret_errno;
2095
}
2096
network.ifr_flags |= IFF_UP; /* set flag */
2097
2098
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2099
if(sd == -1){
2100
ret_errno = errno;
2101
perror_plus("socket");
2102
errno = old_errno;
2103
return ret_errno;
2104
}
2105
2106
if(quit_now){
2107
ret = close(sd);
2108
if(ret == -1){
2109
perror_plus("close");
2110
}
2111
errno = old_errno;
2112
return EINTR;
2113
}
2114
2115
if(debug){
2116
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2117
interface);
2118
}
2119
2120
/* Raise privileges */
2121
ret_errno = raise_privileges();
2122
if(ret_errno != 0){
2123
errno = ret_errno;
2124
perror_plus("Failed to raise privileges");
2125
}
2126
2127
#ifdef __linux__
2128
int ret_linux;
2129
bool restore_loglevel = false;
2130
if(ret_errno == 0){
2131
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2132
messages about the network interface to mess up the prompt */
2133
ret_linux = klogctl(8, NULL, 5);
2134
if(ret_linux == -1){
2135
perror_plus("klogctl");
2136
} else {
2137
restore_loglevel = true;
2138
}
2139
}
2140
#endif /* __linux__ */
2141
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2142
ioctl_errno = errno;
2143
#ifdef __linux__
2144
if(restore_loglevel){
2145
ret_linux = klogctl(7, NULL, 0);
2146
if(ret_linux == -1){
2147
perror_plus("klogctl");
2148
}
2149
}
2150
#endif /* __linux__ */
2151
2152
/* If raise_privileges() succeeded above */
2153
if(ret_errno == 0){
2154
/* Lower privileges */
2155
ret_errno = lower_privileges();
2156
if(ret_errno != 0){
2157
errno = ret_errno;
2158
perror_plus("Failed to lower privileges");
2159
}
2160
}
2161
2162
/* Close the socket */
2163
ret = close(sd);
2164
if(ret == -1){
2165
perror_plus("close");
2166
}
2167
2168
if(ret_setflags == -1){
2169
errno = ioctl_errno;
2170
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2171
errno = old_errno;
2172
return ioctl_errno;
2173
}
2174
} else if(debug){
2175
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2176
interface);
2177
}
2178
2179
/* Sleep checking until interface is running.
2180
Check every 0.25s, up to total time of delay */
2181
for(int i=0; i < delay * 4; i++){
2182
if(interface_is_running(interface)){
2183
break;
2184
}
2185
struct timespec sleeptime = { .tv_nsec = 250000000 };
2186
ret = nanosleep(&sleeptime, NULL);
2187
if(ret == -1 and errno != EINTR){
2188
perror_plus("nanosleep");
2189
}
2190
}
2191
2192
errno = old_errno;
2193
return 0;
2194
}
2195
2196
__attribute__((nonnull, warn_unused_result))
2197
error_t take_down_interface(const char *const interface){
2198
error_t old_errno = errno;
2199
struct ifreq network;
2200
unsigned int if_index = if_nametoindex(interface);
2201
if(if_index == 0){
2202
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2203
errno = old_errno;
2204
return ENXIO;
2205
}
2206
if(interface_is_up(interface)){
2207
error_t ret_errno = 0, ioctl_errno = 0;
2208
if(not get_flags(interface, &network) and debug){
2209
ret_errno = errno;
2210
fprintf_plus(stderr, "Failed to get flags for interface "
2211
"\"%s\"\n", interface);
2212
errno = old_errno;
2213
return ret_errno;
2214
}
2215
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2216
2217
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2218
if(sd == -1){
2219
ret_errno = errno;
2220
perror_plus("socket");
2221
errno = old_errno;
2222
return ret_errno;
2223
}
2224
2225
if(debug){
2226
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2227
interface);
2228
}
2229
2230
/* Raise privileges */
2231
ret_errno = raise_privileges();
2232
if(ret_errno != 0){
2233
errno = ret_errno;
2234
perror_plus("Failed to raise privileges");
2235
}
2236
2237
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2238
ioctl_errno = errno;
2239
2240
/* If raise_privileges() succeeded above */
2241
if(ret_errno == 0){
2242
/* Lower privileges */
2243
ret_errno = lower_privileges();
2244
if(ret_errno != 0){
2245
errno = ret_errno;
2246
perror_plus("Failed to lower privileges");
2247
}
2248
}
2249
2250
/* Close the socket */
2251
int ret = close(sd);
2252
if(ret == -1){
2253
perror_plus("close");
2254
}
2255
2256
if(ret_setflags == -1){
2257
errno = ioctl_errno;
2258
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2259
errno = old_errno;
2260
return ioctl_errno;
2261
}
2262
} else if(debug){
2263
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2264
interface);
2265
}
2266
2267
errno = old_errno;
2268
return 0;
2269
}
2270
2271
int main(int argc, char *argv[]){
2272
mandos_context mc = { .server = NULL, .dh_bits = 0,
2273
.priority = "SECURE256:!CTYPE-X.509"
2274
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2275
.current_server = NULL, .interfaces = NULL,
2276
.interfaces_size = 0 };
2277
AvahiSServiceBrowser *sb = NULL;
2278
error_t ret_errno;
2279
int ret;
2280
intmax_t tmpmax;
2281
char *tmp;
2282
int exitcode = EXIT_SUCCESS;
2283
char *interfaces_to_take_down = NULL;
2284
size_t interfaces_to_take_down_size = 0;
2285
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2286
char old_tempdir[] = "/tmp/mandosXXXXXX";
2287
char *tempdir = NULL;
2288
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2289
const char *seckey = PATHDIR "/" SECKEY;
2290
const char *pubkey = PATHDIR "/" PUBKEY;
2291
const char *dh_params_file = NULL;
2292
char *interfaces_hooks = NULL;
2293
2294
bool gnutls_initialized = false;
2295
bool gpgme_initialized = false;
2296
float delay = 2.5f;
2297
double retry_interval = 10; /* 10s between trying a server and
2298
retrying the same server again */
2299
2300
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2301
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2302
2303
uid = getuid();
2304
gid = getgid();
2305
2306
/* Lower any group privileges we might have, just to be safe */
2307
errno = 0;
2308
ret = setgid(gid);
2309
if(ret == -1){
2310
perror_plus("setgid");
2311
}
2312
2313
/* Lower user privileges (temporarily) */
2314
errno = 0;
2315
ret = seteuid(uid);
2316
if(ret == -1){
2317
perror_plus("seteuid");
2318
}
2319
2320
if(quit_now){
2321
goto end;
2322
}
2323
2324
{
2325
struct argp_option options[] = {
2326
{ .name = "debug", .key = 128,
2327
.doc = "Debug mode", .group = 3 },
2328
{ .name = "connect", .key = 'c',
2329
.arg = "ADDRESS:PORT",
2330
.doc = "Connect directly to a specific Mandos server",
2331
.group = 1 },
2332
{ .name = "interface", .key = 'i',
2333
.arg = "NAME",
2334
.doc = "Network interface that will be used to search for"
2335
" Mandos servers",
2336
.group = 1 },
2337
{ .name = "seckey", .key = 's',
2338
.arg = "FILE",
2339
.doc = "OpenPGP secret key file base name",
2340
.group = 1 },
2341
{ .name = "pubkey", .key = 'p',
2342
.arg = "FILE",
2343
.doc = "OpenPGP public key file base name",
2344
.group = 2 },
2345
{ .name = "dh-bits", .key = 129,
2346
.arg = "BITS",
2347
.doc = "Bit length of the prime number used in the"
2348
" Diffie-Hellman key exchange",
2349
.group = 2 },
2350
{ .name = "dh-params", .key = 134,
2351
.arg = "FILE",
2352
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2353
" for the Diffie-Hellman key exchange",
2354
.group = 2 },
2355
{ .name = "priority", .key = 130,
2356
.arg = "STRING",
2357
.doc = "GnuTLS priority string for the TLS handshake",
2358
.group = 1 },
2359
{ .name = "delay", .key = 131,
2360
.arg = "SECONDS",
2361
.doc = "Maximum delay to wait for interface startup",
2362
.group = 2 },
2363
{ .name = "retry", .key = 132,
2364
.arg = "SECONDS",
2365
.doc = "Retry interval used when denied by the Mandos server",
2366
.group = 2 },
2367
{ .name = "network-hook-dir", .key = 133,
2368
.arg = "DIR",
2369
.doc = "Directory where network hooks are located",
2370
.group = 2 },
2371
/*
2372
* These reproduce what we would get without ARGP_NO_HELP
2373
*/
2374
{ .name = "help", .key = '?',
2375
.doc = "Give this help list", .group = -1 },
2376
{ .name = "usage", .key = -3,
2377
.doc = "Give a short usage message", .group = -1 },
2378
{ .name = "version", .key = 'V',
2379
.doc = "Print program version", .group = -1 },
2380
{ .name = NULL }
2381
};
2382
2383
error_t parse_opt(int key, char *arg,
2384
struct argp_state *state){
2385
errno = 0;
2386
switch(key){
2387
case 128: /* --debug */
2388
debug = true;
2389
break;
2390
case 'c': /* --connect */
2391
connect_to = arg;
2392
break;
2393
case 'i': /* --interface */
2394
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2395
arg, (int)',');
2396
if(ret_errno != 0){
2397
argp_error(state, "%s", strerror(ret_errno));
2398
}
2399
break;
2400
case 's': /* --seckey */
2401
seckey = arg;
2402
break;
2403
case 'p': /* --pubkey */
2404
pubkey = arg;
2405
break;
2406
case 129: /* --dh-bits */
2407
errno = 0;
2408
tmpmax = strtoimax(arg, &tmp, 10);
2409
if(errno != 0 or tmp == arg or *tmp != '\0'
2410
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2411
argp_error(state, "Bad number of DH bits");
2412
}
2413
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2414
break;
2415
case 134: /* --dh-params */
2416
dh_params_file = arg;
2417
break;
2418
case 130: /* --priority */
2419
mc.priority = arg;
2420
break;
2421
case 131: /* --delay */
2422
errno = 0;
2423
delay = strtof(arg, &tmp);
2424
if(errno != 0 or tmp == arg or *tmp != '\0'){
2425
argp_error(state, "Bad delay");
2426
}
2427
case 132: /* --retry */
2428
errno = 0;
2429
retry_interval = strtod(arg, &tmp);
2430
if(errno != 0 or tmp == arg or *tmp != '\0'
2431
or (retry_interval * 1000) > INT_MAX
2432
or retry_interval < 0){
2433
argp_error(state, "Bad retry interval");
2434
}
2435
break;
2436
case 133: /* --network-hook-dir */
2437
hookdir = arg;
2438
break;
2439
/*
2440
* These reproduce what we would get without ARGP_NO_HELP
2441
*/
2442
case '?': /* --help */
2443
argp_state_help(state, state->out_stream,
2444
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2445
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2446
case -3: /* --usage */
2447
argp_state_help(state, state->out_stream,
2448
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2449
case 'V': /* --version */
2450
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2451
exit(argp_err_exit_status);
2452
break;
2453
default:
2454
return ARGP_ERR_UNKNOWN;
2455
}
2456
return errno;
2457
}
2458
2459
struct argp argp = { .options = options, .parser = parse_opt,
2460
.args_doc = "",
2461
.doc = "Mandos client -- Get and decrypt"
2462
" passwords from a Mandos server" };
2463
ret = argp_parse(&argp, argc, argv,
2464
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2465
switch(ret){
2466
case 0:
2467
break;
2468
case ENOMEM:
2469
default:
2470
errno = ret;
2471
perror_plus("argp_parse");
2472
exitcode = EX_OSERR;
2473
goto end;
2474
case EINVAL:
2475
exitcode = EX_USAGE;
2476
goto end;
2477
}
2478
}
2479
2480
{
2481
/* Work around Debian bug #633582:
2482
<http://bugs.debian.org/633582> */
2483
2484
/* Re-raise privileges */
2485
ret_errno = raise_privileges();
2486
if(ret_errno != 0){
2487
errno = ret_errno;
2488
perror_plus("Failed to raise privileges");
2489
} else {
2490
struct stat st;
2491
2492
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2493
int seckey_fd = open(seckey, O_RDONLY);
2494
if(seckey_fd == -1){
2495
perror_plus("open");
2496
} else {
2497
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2498
if(ret == -1){
2499
perror_plus("fstat");
2500
} else {
2501
if(S_ISREG(st.st_mode)
2502
and st.st_uid == 0 and st.st_gid == 0){
2503
ret = fchown(seckey_fd, uid, gid);
2504
if(ret == -1){
2505
perror_plus("fchown");
2506
}
2507
}
2508
}
2509
close(seckey_fd);
2510
}
2511
}
2512
2513
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2514
int pubkey_fd = open(pubkey, O_RDONLY);
2515
if(pubkey_fd == -1){
2516
perror_plus("open");
2517
} else {
2518
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2519
if(ret == -1){
2520
perror_plus("fstat");
2521
} else {
2522
if(S_ISREG(st.st_mode)
2523
and st.st_uid == 0 and st.st_gid == 0){
2524
ret = fchown(pubkey_fd, uid, gid);
2525
if(ret == -1){
2526
perror_plus("fchown");
2527
}
2528
}
2529
}
2530
close(pubkey_fd);
2531
}
2532
}
2533
2534
if(dh_params_file != NULL
2535
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2536
int dhparams_fd = open(dh_params_file, O_RDONLY);
2537
if(dhparams_fd == -1){
2538
perror_plus("open");
2539
} else {
2540
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2541
if(ret == -1){
2542
perror_plus("fstat");
2543
} else {
2544
if(S_ISREG(st.st_mode)
2545
and st.st_uid == 0 and st.st_gid == 0){
2546
ret = fchown(dhparams_fd, uid, gid);
2547
if(ret == -1){
2548
perror_plus("fchown");
2549
}
2550
}
2551
}
2552
close(dhparams_fd);
2553
}
2554
}
2555
2556
/* Lower privileges */
2557
ret_errno = lower_privileges();
2558
if(ret_errno != 0){
2559
errno = ret_errno;
2560
perror_plus("Failed to lower privileges");
2561
}
2562
}
2563
}
2564
2565
/* Remove invalid interface names (except "none") */
2566
{
2567
char *interface = NULL;
2568
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2569
interface))){
2570
if(strcmp(interface, "none") != 0
2571
and if_nametoindex(interface) == 0){
2572
if(interface[0] != '\0'){
2573
fprintf_plus(stderr, "Not using nonexisting interface"
2574
" \"%s\"\n", interface);
2575
}
2576
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2577
interface = NULL;
2578
}
2579
}
2580
}
2581
2582
/* Run network hooks */
2583
{
2584
if(mc.interfaces != NULL){
2585
interfaces_hooks = malloc(mc.interfaces_size);
2586
if(interfaces_hooks == NULL){
2587
perror_plus("malloc");
2588
goto end;
2589
}
2590
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2591
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2592
}
2593
run_network_hooks("start", interfaces_hooks != NULL ?
2594
interfaces_hooks : "", delay);
2595
}
2596
2597
if(not debug){
2598
avahi_set_log_function(empty_log);
2599
}
2600
2601
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2602
from the signal handler */
2603
/* Initialize the pseudo-RNG for Avahi */
2604
srand((unsigned int) time(NULL));
2605
simple_poll = avahi_simple_poll_new();
2606
if(simple_poll == NULL){
2607
fprintf_plus(stderr,
2608
"Avahi: Failed to create simple poll object.\n");
2609
exitcode = EX_UNAVAILABLE;
2610
goto end;
2611
}
2612
2613
sigemptyset(&sigterm_action.sa_mask);
2614
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2615
if(ret == -1){
2616
perror_plus("sigaddset");
2617
exitcode = EX_OSERR;
2618
goto end;
2619
}
2620
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2621
if(ret == -1){
2622
perror_plus("sigaddset");
2623
exitcode = EX_OSERR;
2624
goto end;
2625
}
2626
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2627
if(ret == -1){
2628
perror_plus("sigaddset");
2629
exitcode = EX_OSERR;
2630
goto end;
2631
}
2632
/* Need to check if the handler is SIG_IGN before handling:
2633
| [[info:libc:Initial Signal Actions]] |
2634
| [[info:libc:Basic Signal Handling]] |
2635
*/
2636
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2637
if(ret == -1){
2638
perror_plus("sigaction");
2639
return EX_OSERR;
2640
}
2641
if(old_sigterm_action.sa_handler != SIG_IGN){
2642
ret = sigaction(SIGINT, &sigterm_action, NULL);
2643
if(ret == -1){
2644
perror_plus("sigaction");
2645
exitcode = EX_OSERR;
2646
goto end;
2647
}
2648
}
2649
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2650
if(ret == -1){
2651
perror_plus("sigaction");
2652
return EX_OSERR;
2653
}
2654
if(old_sigterm_action.sa_handler != SIG_IGN){
2655
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2656
if(ret == -1){
2657
perror_plus("sigaction");
2658
exitcode = EX_OSERR;
2659
goto end;
2660
}
2661
}
2662
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2663
if(ret == -1){
2664
perror_plus("sigaction");
2665
return EX_OSERR;
2666
}
2667
if(old_sigterm_action.sa_handler != SIG_IGN){
2668
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2669
if(ret == -1){
2670
perror_plus("sigaction");
2671
exitcode = EX_OSERR;
2672
goto end;
2673
}
2674
}
2675
2676
/* If no interfaces were specified, make a list */
2677
if(mc.interfaces == NULL){
2678
struct dirent **direntries = NULL;
2679
/* Look for any good interfaces */
2680
ret = scandir(sys_class_net, &direntries, good_interface,
2681
alphasort);
2682
if(ret >= 1){
2683
/* Add all found interfaces to interfaces list */
2684
for(int i = 0; i < ret; ++i){
2685
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2686
direntries[i]->d_name);
2687
if(ret_errno != 0){
2688
errno = ret_errno;
2689
perror_plus("argz_add");
2690
free(direntries[i]);
2691
continue;
2692
}
2693
if(debug){
2694
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2695
direntries[i]->d_name);
2696
}
2697
free(direntries[i]);
2698
}
2699
free(direntries);
2700
} else {
2701
if(ret == 0){
2702
free(direntries);
2703
}
2704
fprintf_plus(stderr, "Could not find a network interface\n");
2705
exitcode = EXIT_FAILURE;
2706
goto end;
2707
}
2708
}
2709
2710
/* Bring up interfaces which are down, and remove any "none"s */
2711
{
2712
char *interface = NULL;
2713
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2714
interface))){
2715
/* If interface name is "none", stop bringing up interfaces.
2716
Also remove all instances of "none" from the list */
2717
if(strcmp(interface, "none") == 0){
2718
argz_delete(&mc.interfaces, &mc.interfaces_size,
2719
interface);
2720
interface = NULL;
2721
while((interface = argz_next(mc.interfaces,
2722
mc.interfaces_size, interface))){
2723
if(strcmp(interface, "none") == 0){
2724
argz_delete(&mc.interfaces, &mc.interfaces_size,
2725
interface);
2726
interface = NULL;
2727
}
2728
}
2729
break;
2730
}
2731
bool interface_was_up = interface_is_up(interface);
2732
errno = bring_up_interface(interface, delay);
2733
if(not interface_was_up){
2734
if(errno != 0){
2735
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2736
" %s\n", interface, strerror(errno));
2737
} else {
2738
errno = argz_add(&interfaces_to_take_down,
2739
&interfaces_to_take_down_size,
2740
interface);
2741
if(errno != 0){
2742
perror_plus("argz_add");
2743
}
2744
}
2745
}
2746
}
2747
if(debug and (interfaces_to_take_down == NULL)){
2748
fprintf_plus(stderr, "No interfaces were brought up\n");
2749
}
2750
}
2751
2752
/* If we only got one interface, explicitly use only that one */
2753
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2754
if(debug){
2755
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2756
mc.interfaces);
2757
}
2758
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2759
}
2760
2761
if(quit_now){
2762
goto end;
2763
}
2764
2765
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2766
if(ret == -1){
2767
fprintf_plus(stderr, "init_gnutls_global failed\n");
2768
exitcode = EX_UNAVAILABLE;
2769
goto end;
2770
} else {
2771
gnutls_initialized = true;
2772
}
2773
2774
if(quit_now){
2775
goto end;
2776
}
2777
2778
/* Try /run/tmp before /tmp */
2779
tempdir = mkdtemp(run_tempdir);
2780
if(tempdir == NULL and errno == ENOENT){
2781
if(debug){
2782
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2783
run_tempdir, old_tempdir);
2784
}
2785
tempdir = mkdtemp(old_tempdir);
2786
}
2787
if(tempdir == NULL){
2788
perror_plus("mkdtemp");
2789
goto end;
2790
}
2791
2792
if(quit_now){
2793
goto end;
2794
}
2795
2796
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2797
fprintf_plus(stderr, "init_gpgme failed\n");
2798
exitcode = EX_UNAVAILABLE;
2799
goto end;
2800
} else {
2801
gpgme_initialized = true;
2802
}
2803
2804
if(quit_now){
2805
goto end;
2806
}
2807
2808
if(connect_to != NULL){
2809
/* Connect directly, do not use Zeroconf */
2810
/* (Mainly meant for debugging) */
2811
char *address = strrchr(connect_to, ':');
2812
2813
if(address == NULL){
2814
fprintf_plus(stderr, "No colon in address\n");
2815
exitcode = EX_USAGE;
2816
goto end;
2817
}
2818
2819
if(quit_now){
2820
goto end;
2821
}
2822
2823
in_port_t port;
2824
errno = 0;
2825
tmpmax = strtoimax(address+1, &tmp, 10);
2826
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2827
or tmpmax != (in_port_t)tmpmax){
2828
fprintf_plus(stderr, "Bad port number\n");
2829
exitcode = EX_USAGE;
2830
goto end;
2831
}
2832
2833
if(quit_now){
2834
goto end;
2835
}
2836
2837
port = (in_port_t)tmpmax;
2838
*address = '\0';
2839
/* Colon in address indicates IPv6 */
2840
int af;
2841
if(strchr(connect_to, ':') != NULL){
2842
af = AF_INET6;
2843
/* Accept [] around IPv6 address - see RFC 5952 */
2844
if(connect_to[0] == '[' and address[-1] == ']')
2845
{
2846
connect_to++;
2847
address[-1] = '\0';
2848
}
2849
} else {
2850
af = AF_INET;
2851
}
2852
address = connect_to;
2853
2854
if(quit_now){
2855
goto end;
2856
}
2857
2858
while(not quit_now){
2859
ret = start_mandos_communication(address, port, if_index, af,
2860
&mc);
2861
if(quit_now or ret == 0){
2862
break;
2863
}
2864
if(debug){
2865
fprintf_plus(stderr, "Retrying in %d seconds\n",
2866
(int)retry_interval);
2867
}
2868
sleep((unsigned int)retry_interval);
2869
}
2870
2871
if(not quit_now){
2872
exitcode = EXIT_SUCCESS;
2873
}
2874
2875
goto end;
2876
}
2877
2878
if(quit_now){
2879
goto end;
2880
}
2881
2882
{
2883
AvahiServerConfig config;
2884
/* Do not publish any local Zeroconf records */
2885
avahi_server_config_init(&config);
2886
config.publish_hinfo = 0;
2887
config.publish_addresses = 0;
2888
config.publish_workstation = 0;
2889
config.publish_domain = 0;
2890
2891
/* Allocate a new server */
2892
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2893
&config, NULL, NULL, &ret_errno);
2894
2895
/* Free the Avahi configuration data */
2896
avahi_server_config_free(&config);
2897
}
2898
2899
/* Check if creating the Avahi server object succeeded */
2900
if(mc.server == NULL){
2901
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2902
avahi_strerror(ret_errno));
2903
exitcode = EX_UNAVAILABLE;
2904
goto end;
2905
}
2906
2907
if(quit_now){
2908
goto end;
2909
}
2910
2911
/* Create the Avahi service browser */
2912
sb = avahi_s_service_browser_new(mc.server, if_index,
2913
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2914
NULL, 0, browse_callback,
2915
(void *)&mc);
2916
if(sb == NULL){
2917
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2918
avahi_strerror(avahi_server_errno(mc.server)));
2919
exitcode = EX_UNAVAILABLE;
2920
goto end;
2921
}
2922
2923
if(quit_now){
2924
goto end;
2925
}
2926
2927
/* Run the main loop */
2928
2929
if(debug){
2930
fprintf_plus(stderr, "Starting Avahi loop search\n");
2931
}
2932
2933
ret = avahi_loop_with_timeout(simple_poll,
2934
(int)(retry_interval * 1000), &mc);
2935
if(debug){
2936
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2937
(ret == 0) ? "successfully" : "with error");
2938
}
2939
2940
end:
2941
2942
if(debug){
2943
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2944
}
2945
2946
/* Cleanup things */
2947
free(mc.interfaces);
2948
2949
if(sb != NULL)
2950
avahi_s_service_browser_free(sb);
2951
2952
if(mc.server != NULL)
2953
avahi_server_free(mc.server);
2954
2955
if(simple_poll != NULL)
2956
avahi_simple_poll_free(simple_poll);
2957
2958
if(gnutls_initialized){
2959
gnutls_certificate_free_credentials(mc.cred);
2960
gnutls_dh_params_deinit(mc.dh_params);
2961
}
2962
2963
if(gpgme_initialized){
2964
gpgme_release(mc.ctx);
2965
}
2966
2967
/* Cleans up the circular linked list of Mandos servers the client
2968
has seen */
2969
if(mc.current_server != NULL){
2970
mc.current_server->prev->next = NULL;
2971
while(mc.current_server != NULL){
2972
server *next = mc.current_server->next;
2973
#ifdef __GNUC__
2974
#pragma GCC diagnostic push
2975
#pragma GCC diagnostic ignored "-Wcast-qual"
2976
#endif
2977
free((char *)(mc.current_server->ip));
2978
#ifdef __GNUC__
2979
#pragma GCC diagnostic pop
2980
#endif
2981
free(mc.current_server);
2982
mc.current_server = next;
2983
}
2984
}
2985
2986
/* Re-raise privileges */
2987
{
2988
ret_errno = raise_privileges();
2989
if(ret_errno != 0){
2990
errno = ret_errno;
2991
perror_plus("Failed to raise privileges");
2992
} else {
2993
2994
/* Run network hooks */
2995
run_network_hooks("stop", interfaces_hooks != NULL ?
2996
interfaces_hooks : "", delay);
2997
2998
/* Take down the network interfaces which were brought up */
2999
{
3000
char *interface = NULL;
3001
while((interface=argz_next(interfaces_to_take_down,
3002
interfaces_to_take_down_size,
3003
interface))){
3004
ret_errno = take_down_interface(interface);
3005
if(ret_errno != 0){
3006
errno = ret_errno;
3007
perror_plus("Failed to take down interface");
3008
}
3009
}
3010
if(debug and (interfaces_to_take_down == NULL)){
3011
fprintf_plus(stderr, "No interfaces needed to be taken"
3012
" down\n");
3013
}
3014
}
3015
}
3016
3017
ret_errno = lower_privileges_permanently();
3018
if(ret_errno != 0){
3019
errno = ret_errno;
3020
perror_plus("Failed to lower privileges permanently");
3021
}
3022
}
3023
3024
free(interfaces_to_take_down);
3025
free(interfaces_hooks);
3026
3027
/* Removes the GPGME temp directory and all files inside */
3028
if(tempdir != NULL){
3029
struct dirent **direntries = NULL;
3030
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3031
| O_NOFOLLOW
3032
| O_DIRECTORY
3033
| O_PATH));
3034
if(tempdir_fd == -1){
3035
perror_plus("open");
3036
} else {
3037
int numentries = scandirat(tempdir_fd, ".", &direntries,
3038
notdotentries, alphasort);
3039
if(numentries >= 0){
3040
for(int i = 0; i < numentries; i++){
3041
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3042
if(ret == -1){
3043
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3044
" \"%s\", 0): %s\n", tempdir,
3045
direntries[i]->d_name, strerror(errno));
3046
}
3047
free(direntries[i]);
3048
}
3049
3050
/* need to clean even if 0 because man page doesn't specify */
3051
free(direntries);
3052
if(numentries == -1){
3053
perror_plus("scandir");
3054
}
3055
ret = rmdir(tempdir);
3056
if(ret == -1 and errno != ENOENT){
3057
perror_plus("rmdir");
3058
}
3059
}
3060
close(tempdir_fd);
3061
}
3062
}
3063
3064
if(quit_now){
3065
sigemptyset(&old_sigterm_action.sa_mask);
3066
old_sigterm_action.sa_handler = SIG_DFL;
3067
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3068
&old_sigterm_action,
3069
NULL));
3070
if(ret == -1){
3071
perror_plus("sigaction");
3072
}
3073
do {
3074
ret = raise(signal_received);
3075
} while(ret != 0 and errno == EINTR);
3076
if(ret != 0){
3077
perror_plus("raise");
3078
abort();
3079
}
3080
TEMP_FAILURE_RETRY(pause());
3081
}
3082
3083
return exitcode;
3084
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0