To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/release
« back to all changes in this revision
Viewing changes to plugins.d/mandos-client.c
- browse files at revision 3
- compare with another revision
- download diff
- download tarball
- view history from revision 3
- Committer: Björn Påhlsson
- Date: 2007-12-11 23:40:35 UTC
- Revision ID: belorn@braxen-20071211234035-m1nsu41vuzkak69h
Python based server
Added client configfile
Added client configfile
- files added:
- bad-ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugins.d
- files renamed:
- clients.conf => mandos-clients.conf
- mandos => server.py
- files modified:
- Makefile
added
removed
plugins.d/mandos-client.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos-client - get and decrypt data from a Mandos server
4
*
5
* This program is partly derived from an example program for an Avahi
6
* service browser, downloaded from
7
* <http://avahi.org/browser/examples/core-browse-services.c>. This
8
* includes the following functions: "resolve_callback",
9
* "browse_callback", and parts of "main".
10
*
11
* Everything else is
12
* Copyright © 2008-2014 Teddy Hogeborn
13
* Copyright © 2008-2014 Björn Påhlsson
14
*
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
19
*
20
* This program is distributed in the hope that it will be useful, but
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
* General Public License for more details.
24
*
25
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
*
29
* Contact the authors at <mandos@recompile.se>.
30
*/
31
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
35
#endif /* not _LARGEFILE_SOURCE */
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
38
#endif /* not _FILE_OFFSET_BITS */
39
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
strtof(), abort() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
59
getnameinfo() */
60
#include <fcntl.h> /* open(), unlinkat() */
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
*/
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
strtoimax() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
SIOCSIFFLAGS, if_indextoname(),
70
if_nametoindex(), IF_NAMESIZE */
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
*/
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit(),
77
unlinkat() */
78
#include <arpa/inet.h> /* inet_pton(), htons() */
79
#include <iso646.h> /* not, or, and */
80
#include <argp.h> /* struct argp_option, error_t, struct
81
argp_state, struct argp,
82
argp_parse(), ARGP_KEY_ARG,
83
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
84
#include <signal.h> /* sigemptyset(), sigaddset(),
85
sigaction(), SIGTERM, sig_atomic_t,
86
raise() */
87
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
88
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
90
WEXITSTATUS(), WTERMSIG() */
91
#include <grp.h> /* setgroups() */
92
#include <argz.h> /* argz_add_sep(), argz_next(),
93
argz_delete(), argz_append(),
94
argz_stringify(), argz_add(),
95
argz_count() */
96
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
97
EAI_SYSTEM, gai_strerror() */
98
99
#ifdef __linux__
100
#include <sys/klog.h> /* klogctl() */
101
#endif /* __linux__ */
102
103
/* Avahi */
104
/* All Avahi types, constants and functions
105
Avahi*, avahi_*,
106
AVAHI_* */
107
#include <avahi-core/core.h>
108
#include <avahi-core/lookup.h>
109
#include <avahi-core/log.h>
110
#include <avahi-common/simple-watch.h>
111
#include <avahi-common/malloc.h>
112
#include <avahi-common/error.h>
113
114
/* GnuTLS */
115
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
116
functions:
117
gnutls_*
118
init_gnutls_session(),
119
GNUTLS_* */
120
#include <gnutls/openpgp.h>
121
/* gnutls_certificate_set_openpgp_key_file(),
122
GNUTLS_OPENPGP_FMT_BASE64 */
123
124
/* GPGME */
125
#include <gpgme.h> /* All GPGME types, constants and
126
functions:
127
gpgme_*
128
GPGME_PROTOCOL_OpenPGP,
129
GPG_ERR_NO_* */
130
131
#define BUFFER_SIZE 256
132
133
#define PATHDIR "/conf/conf.d/mandos"
134
#define SECKEY "seckey.txt"
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
137
138
bool debug = false;
139
static const char mandos_protocol_version[] = "1";
140
const char *argp_program_version = "mandos-client " VERSION;
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
142
static const char sys_class_net[] = "/sys/class/net";
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
145
int hookdir_fd = -1;
146
uid_t uid = 65534;
147
gid_t gid = 65534;
148
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
151
const char *ip;
152
in_port_t port;
153
AvahiIfIndex if_index;
154
int af;
155
struct timespec last_seen;
156
struct server *next;
157
struct server *prev;
158
} server;
159
160
/* Used for passing in values through the Avahi callback functions */
161
typedef struct {
162
AvahiServer *server;
163
gnutls_certificate_credentials_t cred;
164
unsigned int dh_bits;
165
gnutls_dh_params_t dh_params;
166
const char *priority;
167
gpgme_ctx_t ctx;
168
server *current_server;
169
char *interfaces;
170
size_t interfaces_size;
171
} mandos_context;
172
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
175
176
sig_atomic_t quit_now = 0;
177
int signal_received = 0;
178
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
181
int e = errno;
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
184
errno = e;
185
perror(print_text);
186
}
187
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
190
va_list ap;
191
va_start (ap, format);
192
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
196
}
197
198
/*
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
200
* bytes. "buffer_capacity" is how much is currently allocated,
201
* "buffer_length" is how much is already used.
202
*/
203
__attribute__((nonnull, warn_unused_result))
204
size_t incbuffer(char **buffer, size_t buffer_length,
205
size_t buffer_capacity){
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
208
if(new_buf == NULL){
209
int old_errno = errno;
210
free(*buffer);
211
errno = old_errno;
212
*buffer = NULL;
213
return 0;
214
}
215
*buffer = new_buf;
216
buffer_capacity += BUFFER_SIZE;
217
}
218
return buffer_capacity;
219
}
220
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
225
int ret;
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
229
return false;
230
}
231
*new_server = (server){ .ip = strdup(ip),
232
.port = port,
233
.if_index = if_index,
234
.af = af };
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
237
free(new_server);
238
return false;
239
}
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
241
if(ret == -1){
242
perror_plus("clock_gettime");
243
#ifdef __GNUC__
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
246
#endif
247
free((char *)(new_server->ip));
248
#ifdef __GNUC__
249
#pragma GCC diagnostic pop
250
#endif
251
free(new_server);
252
return false;
253
}
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
259
} else {
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
265
}
266
return true;
267
}
268
269
/*
270
* Initialize GPGME.
271
*/
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
276
mandos_context *mc){
277
gpgme_error_t rc;
278
gpgme_engine_info_t engine_info;
279
280
/*
281
* Helper function to insert pub and seckey to the engine keyring.
282
*/
283
bool import_key(const char * const filename){
284
int ret;
285
int fd;
286
gpgme_data_t pgp_data;
287
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
289
if(fd == -1){
290
perror_plus("open");
291
return false;
292
}
293
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
295
if(rc != GPG_ERR_NO_ERROR){
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
298
return false;
299
}
300
301
rc = gpgme_op_import(mc->ctx, pgp_data);
302
if(rc != GPG_ERR_NO_ERROR){
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
305
return false;
306
}
307
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
309
if(ret == -1){
310
perror_plus("close");
311
}
312
gpgme_data_release(pgp_data);
313
return true;
314
}
315
316
if(debug){
317
fprintf_plus(stderr, "Initializing GPGME\n");
318
}
319
320
/* Init GPGME */
321
gpgme_check_version(NULL);
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
323
if(rc != GPG_ERR_NO_ERROR){
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
326
return false;
327
}
328
329
/* Set GPGME home directory for the OpenPGP engine only */
330
rc = gpgme_get_engine_info(&engine_info);
331
if(rc != GPG_ERR_NO_ERROR){
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
gpgme_strsource(rc), gpgme_strerror(rc));
334
return false;
335
}
336
while(engine_info != NULL){
337
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
338
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
339
engine_info->file_name, tempdir);
340
break;
341
}
342
engine_info = engine_info->next;
343
}
344
if(engine_info == NULL){
345
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
346
tempdir);
347
return false;
348
}
349
350
/* Create new GPGME "context" */
351
rc = gpgme_new(&(mc->ctx));
352
if(rc != GPG_ERR_NO_ERROR){
353
fprintf_plus(stderr, "Mandos plugin mandos-client: "
354
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
355
gpgme_strerror(rc));
356
return false;
357
}
358
359
if(not import_key(pubkey) or not import_key(seckey)){
360
return false;
361
}
362
363
return true;
364
}
365
366
/*
367
* Decrypt OpenPGP data.
368
* Returns -1 on error
369
*/
370
__attribute__((nonnull, warn_unused_result))
371
static ssize_t pgp_packet_decrypt(const char *cryptotext,
372
size_t crypto_size,
373
char **plaintext,
374
mandos_context *mc){
375
gpgme_data_t dh_crypto, dh_plain;
376
gpgme_error_t rc;
377
ssize_t ret;
378
size_t plaintext_capacity = 0;
379
ssize_t plaintext_length = 0;
380
381
if(debug){
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
383
}
384
385
/* Create new GPGME data buffer from memory cryptotext */
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
387
0);
388
if(rc != GPG_ERR_NO_ERROR){
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
391
return -1;
392
}
393
394
/* Create new empty GPGME data buffer for the plaintext */
395
rc = gpgme_data_new(&dh_plain);
396
if(rc != GPG_ERR_NO_ERROR){
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
400
gpgme_data_release(dh_crypto);
401
return -1;
402
}
403
404
/* Decrypt data from the cryptotext data buffer to the plaintext
405
data buffer */
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
407
if(rc != GPG_ERR_NO_ERROR){
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
410
plaintext_length = -1;
411
if(debug){
412
gpgme_decrypt_result_t result;
413
result = gpgme_op_decrypt_result(mc->ctx);
414
if(result == NULL){
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
416
} else {
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
421
if(result->file_name != NULL){
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
423
}
424
gpgme_recipient_t recipient;
425
recipient = result->recipients;
426
while(recipient != NULL){
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
433
? "No" : "Yes");
434
recipient = recipient->next;
435
}
436
}
437
}
438
goto decrypt_end;
439
}
440
441
if(debug){
442
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
443
}
444
445
/* Seek back to the beginning of the GPGME plaintext data buffer */
446
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
447
perror_plus("gpgme_data_seek");
448
plaintext_length = -1;
449
goto decrypt_end;
450
}
451
452
*plaintext = NULL;
453
while(true){
454
plaintext_capacity = incbuffer(plaintext,
455
(size_t)plaintext_length,
456
plaintext_capacity);
457
if(plaintext_capacity == 0){
458
perror_plus("incbuffer");
459
plaintext_length = -1;
460
goto decrypt_end;
461
}
462
463
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
464
BUFFER_SIZE);
465
/* Print the data, if any */
466
if(ret == 0){
467
/* EOF */
468
break;
469
}
470
if(ret < 0){
471
perror_plus("gpgme_data_read");
472
plaintext_length = -1;
473
goto decrypt_end;
474
}
475
plaintext_length += ret;
476
}
477
478
if(debug){
479
fprintf_plus(stderr, "Decrypted password is: ");
480
for(ssize_t i = 0; i < plaintext_length; i++){
481
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
482
}
483
fprintf(stderr, "\n");
484
}
485
486
decrypt_end:
487
488
/* Delete the GPGME cryptotext data buffer */
489
gpgme_data_release(dh_crypto);
490
491
/* Delete the GPGME plaintext data buffer */
492
gpgme_data_release(dh_plain);
493
return plaintext_length;
494
}
495
496
__attribute__((warn_unused_result))
497
static const char *safer_gnutls_strerror(int value){
498
const char *ret = gnutls_strerror(value);
499
if(ret == NULL)
500
ret = "(unknown)";
501
return ret;
502
}
503
504
/* GnuTLS log function callback */
505
__attribute__((nonnull))
506
static void debuggnutls(__attribute__((unused)) int level,
507
const char* string){
508
fprintf_plus(stderr, "GnuTLS: %s", string);
509
}
510
511
__attribute__((nonnull, warn_unused_result))
512
static int init_gnutls_global(const char *pubkeyfilename,
513
const char *seckeyfilename,
514
mandos_context *mc){
515
int ret;
516
517
if(debug){
518
fprintf_plus(stderr, "Initializing GnuTLS\n");
519
}
520
521
ret = gnutls_global_init();
522
if(ret != GNUTLS_E_SUCCESS){
523
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
524
safer_gnutls_strerror(ret));
525
return -1;
526
}
527
528
if(debug){
529
/* "Use a log level over 10 to enable all debugging options."
530
* - GnuTLS manual
531
*/
532
gnutls_global_set_log_level(11);
533
gnutls_global_set_log_function(debuggnutls);
534
}
535
536
/* OpenPGP credentials */
537
ret = gnutls_certificate_allocate_credentials(&mc->cred);
538
if(ret != GNUTLS_E_SUCCESS){
539
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
540
safer_gnutls_strerror(ret));
541
gnutls_global_deinit();
542
return -1;
543
}
544
545
if(debug){
546
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
547
" secret key %s as GnuTLS credentials\n",
548
pubkeyfilename,
549
seckeyfilename);
550
}
551
552
ret = gnutls_certificate_set_openpgp_key_file
553
(mc->cred, pubkeyfilename, seckeyfilename,
554
GNUTLS_OPENPGP_FMT_BASE64);
555
if(ret != GNUTLS_E_SUCCESS){
556
fprintf_plus(stderr,
557
"Error[%d] while reading the OpenPGP key pair ('%s',"
558
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
559
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
560
safer_gnutls_strerror(ret));
561
goto globalfail;
562
}
563
564
/* GnuTLS server initialization */
565
ret = gnutls_dh_params_init(&mc->dh_params);
566
if(ret != GNUTLS_E_SUCCESS){
567
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
568
" initialization: %s\n",
569
safer_gnutls_strerror(ret));
570
goto globalfail;
571
}
572
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
575
safer_gnutls_strerror(ret));
576
goto globalfail;
577
}
578
579
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
580
581
return 0;
582
583
globalfail:
584
585
gnutls_certificate_free_credentials(mc->cred);
586
gnutls_global_deinit();
587
gnutls_dh_params_deinit(mc->dh_params);
588
return -1;
589
}
590
591
__attribute__((nonnull, warn_unused_result))
592
static int init_gnutls_session(gnutls_session_t *session,
593
mandos_context *mc){
594
int ret;
595
/* GnuTLS session creation */
596
do {
597
ret = gnutls_init(session, GNUTLS_SERVER);
598
if(quit_now){
599
return -1;
600
}
601
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
602
if(ret != GNUTLS_E_SUCCESS){
603
fprintf_plus(stderr,
604
"Error in GnuTLS session initialization: %s\n",
605
safer_gnutls_strerror(ret));
606
}
607
608
{
609
const char *err;
610
do {
611
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
612
if(quit_now){
613
gnutls_deinit(*session);
614
return -1;
615
}
616
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
617
if(ret != GNUTLS_E_SUCCESS){
618
fprintf_plus(stderr, "Syntax error at: %s\n", err);
619
fprintf_plus(stderr, "GnuTLS error: %s\n",
620
safer_gnutls_strerror(ret));
621
gnutls_deinit(*session);
622
return -1;
623
}
624
}
625
626
do {
627
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
628
mc->cred);
629
if(quit_now){
630
gnutls_deinit(*session);
631
return -1;
632
}
633
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
634
if(ret != GNUTLS_E_SUCCESS){
635
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
636
safer_gnutls_strerror(ret));
637
gnutls_deinit(*session);
638
return -1;
639
}
640
641
/* ignore client certificate if any. */
642
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
643
644
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
645
646
return 0;
647
}
648
649
/* Avahi log function callback */
650
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
651
__attribute__((unused)) const char *txt){}
652
653
/* Called when a Mandos server is found */
654
__attribute__((nonnull, warn_unused_result))
655
static int start_mandos_communication(const char *ip, in_port_t port,
656
AvahiIfIndex if_index,
657
int af, mandos_context *mc){
658
int ret, tcp_sd = -1;
659
ssize_t sret;
660
struct sockaddr_storage to;
661
char *buffer = NULL;
662
char *decrypted_buffer = NULL;
663
size_t buffer_length = 0;
664
size_t buffer_capacity = 0;
665
size_t written;
666
int retval = -1;
667
gnutls_session_t session;
668
int pf; /* Protocol family */
669
670
errno = 0;
671
672
if(quit_now){
673
errno = EINTR;
674
return -1;
675
}
676
677
switch(af){
678
case AF_INET6:
679
pf = PF_INET6;
680
break;
681
case AF_INET:
682
pf = PF_INET;
683
break;
684
default:
685
fprintf_plus(stderr, "Bad address family: %d\n", af);
686
errno = EINVAL;
687
return -1;
688
}
689
690
/* If the interface is specified and we have a list of interfaces */
691
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
692
/* Check if the interface is one of the interfaces we are using */
693
bool match = false;
694
{
695
char *interface = NULL;
696
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
697
interface))){
698
if(if_nametoindex(interface) == (unsigned int)if_index){
699
match = true;
700
break;
701
}
702
}
703
}
704
if(not match){
705
/* This interface does not match any in the list, so we don't
706
connect to the server */
707
if(debug){
708
char interface[IF_NAMESIZE];
709
if(if_indextoname((unsigned int)if_index, interface) == NULL){
710
perror_plus("if_indextoname");
711
} else {
712
fprintf_plus(stderr, "Skipping server on non-used interface"
713
" \"%s\"\n",
714
if_indextoname((unsigned int)if_index,
715
interface));
716
}
717
}
718
return -1;
719
}
720
}
721
722
ret = init_gnutls_session(&session, mc);
723
if(ret != 0){
724
return -1;
725
}
726
727
if(debug){
728
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
729
PRIuMAX "\n", ip, (uintmax_t)port);
730
}
731
732
tcp_sd = socket(pf, SOCK_STREAM, 0);
733
if(tcp_sd < 0){
734
int e = errno;
735
perror_plus("socket");
736
errno = e;
737
goto mandos_end;
738
}
739
740
if(quit_now){
741
errno = EINTR;
742
goto mandos_end;
743
}
744
745
memset(&to, 0, sizeof(to));
746
if(af == AF_INET6){
747
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
748
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
749
} else { /* IPv4 */
750
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
751
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
752
}
753
if(ret < 0 ){
754
int e = errno;
755
perror_plus("inet_pton");
756
errno = e;
757
goto mandos_end;
758
}
759
if(ret == 0){
760
int e = errno;
761
fprintf_plus(stderr, "Bad address: %s\n", ip);
762
errno = e;
763
goto mandos_end;
764
}
765
if(af == AF_INET6){
766
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
767
if(IN6_IS_ADDR_LINKLOCAL
768
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
769
if(if_index == AVAHI_IF_UNSPEC){
770
fprintf_plus(stderr, "An IPv6 link-local address is"
771
" incomplete without a network interface\n");
772
errno = EINVAL;
773
goto mandos_end;
774
}
775
/* Set the network interface number as scope */
776
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
777
}
778
} else {
779
((struct sockaddr_in *)&to)->sin_port = htons(port);
780
}
781
782
if(quit_now){
783
errno = EINTR;
784
goto mandos_end;
785
}
786
787
if(debug){
788
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
789
char interface[IF_NAMESIZE];
790
if(if_indextoname((unsigned int)if_index, interface) == NULL){
791
perror_plus("if_indextoname");
792
} else {
793
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
794
"\n", ip, interface, (uintmax_t)port);
795
}
796
} else {
797
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
798
ip, (uintmax_t)port);
799
}
800
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
801
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
802
if(af == AF_INET6){
803
ret = getnameinfo((struct sockaddr *)&to,
804
sizeof(struct sockaddr_in6),
805
addrstr, sizeof(addrstr), NULL, 0,
806
NI_NUMERICHOST);
807
} else {
808
ret = getnameinfo((struct sockaddr *)&to,
809
sizeof(struct sockaddr_in),
810
addrstr, sizeof(addrstr), NULL, 0,
811
NI_NUMERICHOST);
812
}
813
if(ret == EAI_SYSTEM){
814
perror_plus("getnameinfo");
815
} else if(ret != 0) {
816
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
817
} else if(strcmp(addrstr, ip) != 0){
818
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
819
}
820
}
821
822
if(quit_now){
823
errno = EINTR;
824
goto mandos_end;
825
}
826
827
if(af == AF_INET6){
828
ret = connect(tcp_sd, (struct sockaddr *)&to,
829
sizeof(struct sockaddr_in6));
830
} else {
831
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
832
sizeof(struct sockaddr_in));
833
}
834
if(ret < 0){
835
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
836
int e = errno;
837
perror_plus("connect");
838
errno = e;
839
}
840
goto mandos_end;
841
}
842
843
if(quit_now){
844
errno = EINTR;
845
goto mandos_end;
846
}
847
848
const char *out = mandos_protocol_version;
849
written = 0;
850
while(true){
851
size_t out_size = strlen(out);
852
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
853
out_size - written));
854
if(ret == -1){
855
int e = errno;
856
perror_plus("write");
857
errno = e;
858
goto mandos_end;
859
}
860
written += (size_t)ret;
861
if(written < out_size){
862
continue;
863
} else {
864
if(out == mandos_protocol_version){
865
written = 0;
866
out = "\r\n";
867
} else {
868
break;
869
}
870
}
871
872
if(quit_now){
873
errno = EINTR;
874
goto mandos_end;
875
}
876
}
877
878
if(debug){
879
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
880
}
881
882
if(quit_now){
883
errno = EINTR;
884
goto mandos_end;
885
}
886
887
/* This casting via intptr_t is to eliminate warning about casting
888
an int to a pointer type. This is exactly how the GnuTLS Guile
889
function "set-session-transport-fd!" does it. */
890
gnutls_transport_set_ptr(session,
891
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
892
893
if(quit_now){
894
errno = EINTR;
895
goto mandos_end;
896
}
897
898
do {
899
ret = gnutls_handshake(session);
900
if(quit_now){
901
errno = EINTR;
902
goto mandos_end;
903
}
904
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
905
906
if(ret != GNUTLS_E_SUCCESS){
907
if(debug){
908
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
909
gnutls_perror(ret);
910
}
911
errno = EPROTO;
912
goto mandos_end;
913
}
914
915
/* Read OpenPGP packet that contains the wanted password */
916
917
if(debug){
918
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
919
" %s\n", ip);
920
}
921
922
while(true){
923
924
if(quit_now){
925
errno = EINTR;
926
goto mandos_end;
927
}
928
929
buffer_capacity = incbuffer(&buffer, buffer_length,
930
buffer_capacity);
931
if(buffer_capacity == 0){
932
int e = errno;
933
perror_plus("incbuffer");
934
errno = e;
935
goto mandos_end;
936
}
937
938
if(quit_now){
939
errno = EINTR;
940
goto mandos_end;
941
}
942
943
sret = gnutls_record_recv(session, buffer+buffer_length,
944
BUFFER_SIZE);
945
if(sret == 0){
946
break;
947
}
948
if(sret < 0){
949
switch(sret){
950
case GNUTLS_E_INTERRUPTED:
951
case GNUTLS_E_AGAIN:
952
break;
953
case GNUTLS_E_REHANDSHAKE:
954
do {
955
ret = gnutls_handshake(session);
956
957
if(quit_now){
958
errno = EINTR;
959
goto mandos_end;
960
}
961
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
962
if(ret < 0){
963
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
964
"***\n");
965
gnutls_perror(ret);
966
errno = EPROTO;
967
goto mandos_end;
968
}
969
break;
970
default:
971
fprintf_plus(stderr, "Unknown error while reading data from"
972
" encrypted session with Mandos server\n");
973
gnutls_bye(session, GNUTLS_SHUT_RDWR);
974
errno = EIO;
975
goto mandos_end;
976
}
977
} else {
978
buffer_length += (size_t) sret;
979
}
980
}
981
982
if(debug){
983
fprintf_plus(stderr, "Closing TLS session\n");
984
}
985
986
if(quit_now){
987
errno = EINTR;
988
goto mandos_end;
989
}
990
991
do {
992
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
993
if(quit_now){
994
errno = EINTR;
995
goto mandos_end;
996
}
997
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
998
999
if(buffer_length > 0){
1000
ssize_t decrypted_buffer_size;
1001
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1002
&decrypted_buffer, mc);
1003
if(decrypted_buffer_size >= 0){
1004
1005
written = 0;
1006
while(written < (size_t) decrypted_buffer_size){
1007
if(quit_now){
1008
errno = EINTR;
1009
goto mandos_end;
1010
}
1011
1012
ret = (int)fwrite(decrypted_buffer + written, 1,
1013
(size_t)decrypted_buffer_size - written,
1014
stdout);
1015
if(ret == 0 and ferror(stdout)){
1016
int e = errno;
1017
if(debug){
1018
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1019
strerror(errno));
1020
}
1021
errno = e;
1022
goto mandos_end;
1023
}
1024
written += (size_t)ret;
1025
}
1026
retval = 0;
1027
}
1028
}
1029
1030
/* Shutdown procedure */
1031
1032
mandos_end:
1033
{
1034
int e = errno;
1035
free(decrypted_buffer);
1036
free(buffer);
1037
if(tcp_sd >= 0){
1038
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1039
}
1040
if(ret == -1){
1041
if(e == 0){
1042
e = errno;
1043
}
1044
perror_plus("close");
1045
}
1046
gnutls_deinit(session);
1047
errno = e;
1048
if(quit_now){
1049
errno = EINTR;
1050
retval = -1;
1051
}
1052
}
1053
return retval;
1054
}
1055
1056
__attribute__((nonnull))
1057
static void resolve_callback(AvahiSServiceResolver *r,
1058
AvahiIfIndex interface,
1059
AvahiProtocol proto,
1060
AvahiResolverEvent event,
1061
const char *name,
1062
const char *type,
1063
const char *domain,
1064
const char *host_name,
1065
const AvahiAddress *address,
1066
uint16_t port,
1067
AVAHI_GCC_UNUSED AvahiStringList *txt,
1068
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1069
flags,
1070
void *mc){
1071
if(r == NULL){
1072
return;
1073
}
1074
1075
/* Called whenever a service has been resolved successfully or
1076
timed out */
1077
1078
if(quit_now){
1079
avahi_s_service_resolver_free(r);
1080
return;
1081
}
1082
1083
switch(event){
1084
default:
1085
case AVAHI_RESOLVER_FAILURE:
1086
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1087
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1088
domain,
1089
avahi_strerror(avahi_server_errno
1090
(((mandos_context*)mc)->server)));
1091
break;
1092
1093
case AVAHI_RESOLVER_FOUND:
1094
{
1095
char ip[AVAHI_ADDRESS_STR_MAX];
1096
avahi_address_snprint(ip, sizeof(ip), address);
1097
if(debug){
1098
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1099
PRIdMAX ") on port %" PRIu16 "\n", name,
1100
host_name, ip, (intmax_t)interface, port);
1101
}
1102
int ret = start_mandos_communication(ip, (in_port_t)port,
1103
interface,
1104
avahi_proto_to_af(proto),
1105
mc);
1106
if(ret == 0){
1107
avahi_simple_poll_quit(simple_poll);
1108
} else {
1109
if(not add_server(ip, (in_port_t)port, interface,
1110
avahi_proto_to_af(proto),
1111
&((mandos_context*)mc)->current_server)){
1112
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1113
" list\n", name);
1114
}
1115
}
1116
}
1117
}
1118
avahi_s_service_resolver_free(r);
1119
}
1120
1121
static void browse_callback(AvahiSServiceBrowser *b,
1122
AvahiIfIndex interface,
1123
AvahiProtocol protocol,
1124
AvahiBrowserEvent event,
1125
const char *name,
1126
const char *type,
1127
const char *domain,
1128
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1129
flags,
1130
void *mc){
1131
if(b == NULL){
1132
return;
1133
}
1134
1135
/* Called whenever a new services becomes available on the LAN or
1136
is removed from the LAN */
1137
1138
if(quit_now){
1139
return;
1140
}
1141
1142
switch(event){
1143
default:
1144
case AVAHI_BROWSER_FAILURE:
1145
1146
fprintf_plus(stderr, "(Avahi browser) %s\n",
1147
avahi_strerror(avahi_server_errno
1148
(((mandos_context*)mc)->server)));
1149
avahi_simple_poll_quit(simple_poll);
1150
return;
1151
1152
case AVAHI_BROWSER_NEW:
1153
/* We ignore the returned Avahi resolver object. In the callback
1154
function we free it. If the Avahi server is terminated before
1155
the callback function is called the Avahi server will free the
1156
resolver for us. */
1157
1158
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1159
interface, protocol, name, type,
1160
domain, protocol, 0,
1161
resolve_callback, mc) == NULL)
1162
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1163
" %s\n", name,
1164
avahi_strerror(avahi_server_errno
1165
(((mandos_context*)mc)->server)));
1166
break;
1167
1168
case AVAHI_BROWSER_REMOVE:
1169
break;
1170
1171
case AVAHI_BROWSER_ALL_FOR_NOW:
1172
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1173
if(debug){
1174
fprintf_plus(stderr, "No Mandos server found, still"
1175
" searching...\n");
1176
}
1177
break;
1178
}
1179
}
1180
1181
/* Signal handler that stops main loop after SIGTERM */
1182
static void handle_sigterm(int sig){
1183
if(quit_now){
1184
return;
1185
}
1186
quit_now = 1;
1187
signal_received = sig;
1188
int old_errno = errno;
1189
/* set main loop to exit */
1190
if(simple_poll != NULL){
1191
avahi_simple_poll_quit(simple_poll);
1192
}
1193
errno = old_errno;
1194
}
1195
1196
__attribute__((nonnull, warn_unused_result))
1197
bool get_flags(const char *ifname, struct ifreq *ifr){
1198
int ret;
1199
error_t ret_errno;
1200
1201
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1202
if(s < 0){
1203
ret_errno = errno;
1204
perror_plus("socket");
1205
errno = ret_errno;
1206
return false;
1207
}
1208
strcpy(ifr->ifr_name, ifname);
1209
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1210
if(ret == -1){
1211
if(debug){
1212
ret_errno = errno;
1213
perror_plus("ioctl SIOCGIFFLAGS");
1214
errno = ret_errno;
1215
}
1216
return false;
1217
}
1218
return true;
1219
}
1220
1221
__attribute__((nonnull, warn_unused_result))
1222
bool good_flags(const char *ifname, const struct ifreq *ifr){
1223
1224
/* Reject the loopback device */
1225
if(ifr->ifr_flags & IFF_LOOPBACK){
1226
if(debug){
1227
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1228
ifname);
1229
}
1230
return false;
1231
}
1232
/* Accept point-to-point devices only if connect_to is specified */
1233
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1234
if(debug){
1235
fprintf_plus(stderr, "Accepting point-to-point interface"
1236
" \"%s\"\n", ifname);
1237
}
1238
return true;
1239
}
1240
/* Otherwise, reject non-broadcast-capable devices */
1241
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1242
if(debug){
1243
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1244
" \"%s\"\n", ifname);
1245
}
1246
return false;
1247
}
1248
/* Reject non-ARP interfaces (including dummy interfaces) */
1249
if(ifr->ifr_flags & IFF_NOARP){
1250
if(debug){
1251
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1252
ifname);
1253
}
1254
return false;
1255
}
1256
1257
/* Accept this device */
1258
if(debug){
1259
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1260
}
1261
return true;
1262
}
1263
1264
/*
1265
* This function determines if a directory entry in /sys/class/net
1266
* corresponds to an acceptable network device.
1267
* (This function is passed to scandir(3) as a filter function.)
1268
*/
1269
__attribute__((nonnull, warn_unused_result))
1270
int good_interface(const struct dirent *if_entry){
1271
if(if_entry->d_name[0] == '.'){
1272
return 0;
1273
}
1274
1275
struct ifreq ifr;
1276
if(not get_flags(if_entry->d_name, &ifr)){
1277
if(debug){
1278
fprintf_plus(stderr, "Failed to get flags for interface "
1279
"\"%s\"\n", if_entry->d_name);
1280
}
1281
return 0;
1282
}
1283
1284
if(not good_flags(if_entry->d_name, &ifr)){
1285
return 0;
1286
}
1287
return 1;
1288
}
1289
1290
/*
1291
* This function determines if a network interface is up.
1292
*/
1293
__attribute__((nonnull, warn_unused_result))
1294
bool interface_is_up(const char *interface){
1295
struct ifreq ifr;
1296
if(not get_flags(interface, &ifr)){
1297
if(debug){
1298
fprintf_plus(stderr, "Failed to get flags for interface "
1299
"\"%s\"\n", interface);
1300
}
1301
return false;
1302
}
1303
1304
return (bool)(ifr.ifr_flags & IFF_UP);
1305
}
1306
1307
/*
1308
* This function determines if a network interface is running
1309
*/
1310
__attribute__((nonnull, warn_unused_result))
1311
bool interface_is_running(const char *interface){
1312
struct ifreq ifr;
1313
if(not get_flags(interface, &ifr)){
1314
if(debug){
1315
fprintf_plus(stderr, "Failed to get flags for interface "
1316
"\"%s\"\n", interface);
1317
}
1318
return false;
1319
}
1320
1321
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1322
}
1323
1324
__attribute__((nonnull, pure, warn_unused_result))
1325
int notdotentries(const struct dirent *direntry){
1326
/* Skip "." and ".." */
1327
if(direntry->d_name[0] == '.'
1328
and (direntry->d_name[1] == '\0'
1329
or (direntry->d_name[1] == '.'
1330
and direntry->d_name[2] == '\0'))){
1331
return 0;
1332
}
1333
return 1;
1334
}
1335
1336
/* Is this directory entry a runnable program? */
1337
__attribute__((nonnull, warn_unused_result))
1338
int runnable_hook(const struct dirent *direntry){
1339
int ret;
1340
size_t sret;
1341
struct stat st;
1342
1343
if((direntry->d_name)[0] == '\0'){
1344
/* Empty name? */
1345
return 0;
1346
}
1347
1348
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1349
"abcdefghijklmnopqrstuvwxyz"
1350
"0123456789"
1351
"_.-");
1352
if((direntry->d_name)[sret] != '\0'){
1353
/* Contains non-allowed characters */
1354
if(debug){
1355
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1356
direntry->d_name);
1357
}
1358
return 0;
1359
}
1360
1361
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1362
if(ret == -1){
1363
if(debug){
1364
perror_plus("Could not stat hook");
1365
}
1366
return 0;
1367
}
1368
if(not (S_ISREG(st.st_mode))){
1369
/* Not a regular file */
1370
if(debug){
1371
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1372
direntry->d_name);
1373
}
1374
return 0;
1375
}
1376
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1377
/* Not executable */
1378
if(debug){
1379
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1380
direntry->d_name);
1381
}
1382
return 0;
1383
}
1384
if(debug){
1385
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1386
direntry->d_name);
1387
}
1388
return 1;
1389
}
1390
1391
__attribute__((nonnull, warn_unused_result))
1392
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1393
mandos_context *mc){
1394
int ret;
1395
struct timespec now;
1396
struct timespec waited_time;
1397
intmax_t block_time;
1398
1399
while(true){
1400
if(mc->current_server == NULL){
1401
if(debug){
1402
fprintf_plus(stderr, "Wait until first server is found."
1403
" No timeout!\n");
1404
}
1405
ret = avahi_simple_poll_iterate(s, -1);
1406
} else {
1407
if(debug){
1408
fprintf_plus(stderr, "Check current_server if we should run"
1409
" it, or wait\n");
1410
}
1411
/* the current time */
1412
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1413
if(ret == -1){
1414
perror_plus("clock_gettime");
1415
return -1;
1416
}
1417
/* Calculating in ms how long time between now and server
1418
who we visted longest time ago. Now - last seen. */
1419
waited_time.tv_sec = (now.tv_sec
1420
- mc->current_server->last_seen.tv_sec);
1421
waited_time.tv_nsec = (now.tv_nsec
1422
- mc->current_server->last_seen.tv_nsec);
1423
/* total time is 10s/10,000ms.
1424
Converting to s from ms by dividing by 1,000,
1425
and ns to ms by dividing by 1,000,000. */
1426
block_time = ((retry_interval
1427
- ((intmax_t)waited_time.tv_sec * 1000))
1428
- ((intmax_t)waited_time.tv_nsec / 1000000));
1429
1430
if(debug){
1431
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1432
block_time);
1433
}
1434
1435
if(block_time <= 0){
1436
ret = start_mandos_communication(mc->current_server->ip,
1437
mc->current_server->port,
1438
mc->current_server->if_index,
1439
mc->current_server->af, mc);
1440
if(ret == 0){
1441
avahi_simple_poll_quit(s);
1442
return 0;
1443
}
1444
ret = clock_gettime(CLOCK_MONOTONIC,
1445
&mc->current_server->last_seen);
1446
if(ret == -1){
1447
perror_plus("clock_gettime");
1448
return -1;
1449
}
1450
mc->current_server = mc->current_server->next;
1451
block_time = 0; /* Call avahi to find new Mandos
1452
servers, but don't block */
1453
}
1454
1455
ret = avahi_simple_poll_iterate(s, (int)block_time);
1456
}
1457
if(ret != 0){
1458
if(ret > 0 or errno != EINTR){
1459
return (ret != 1) ? ret : 0;
1460
}
1461
}
1462
}
1463
}
1464
1465
/* Set effective uid to 0, return errno */
1466
__attribute__((warn_unused_result))
1467
error_t raise_privileges(void){
1468
error_t old_errno = errno;
1469
error_t ret_errno = 0;
1470
if(seteuid(0) == -1){
1471
ret_errno = errno;
1472
}
1473
errno = old_errno;
1474
return ret_errno;
1475
}
1476
1477
/* Set effective and real user ID to 0. Return errno. */
1478
__attribute__((warn_unused_result))
1479
error_t raise_privileges_permanently(void){
1480
error_t old_errno = errno;
1481
error_t ret_errno = raise_privileges();
1482
if(ret_errno != 0){
1483
errno = old_errno;
1484
return ret_errno;
1485
}
1486
if(setuid(0) == -1){
1487
ret_errno = errno;
1488
}
1489
errno = old_errno;
1490
return ret_errno;
1491
}
1492
1493
/* Set effective user ID to unprivileged saved user ID */
1494
__attribute__((warn_unused_result))
1495
error_t lower_privileges(void){
1496
error_t old_errno = errno;
1497
error_t ret_errno = 0;
1498
if(seteuid(uid) == -1){
1499
ret_errno = errno;
1500
}
1501
errno = old_errno;
1502
return ret_errno;
1503
}
1504
1505
/* Lower privileges permanently */
1506
__attribute__((warn_unused_result))
1507
error_t lower_privileges_permanently(void){
1508
error_t old_errno = errno;
1509
error_t ret_errno = 0;
1510
if(setuid(uid) == -1){
1511
ret_errno = errno;
1512
}
1513
errno = old_errno;
1514
return ret_errno;
1515
}
1516
1517
__attribute__((nonnull))
1518
void run_network_hooks(const char *mode, const char *interface,
1519
const float delay){
1520
struct dirent **direntries = NULL;
1521
if(hookdir_fd == -1){
1522
hookdir_fd = open(hookdir, O_RDONLY);
1523
if(hookdir_fd == -1){
1524
if(errno == ENOENT){
1525
if(debug){
1526
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1527
" found\n", hookdir);
1528
}
1529
} else {
1530
perror_plus("open");
1531
}
1532
return;
1533
}
1534
}
1535
#ifdef __GLIBC__
1536
#if __GLIBC_PREREQ(2, 15)
1537
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1538
runnable_hook, alphasort);
1539
#else /* not __GLIBC_PREREQ(2, 15) */
1540
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1541
alphasort);
1542
#endif /* not __GLIBC_PREREQ(2, 15) */
1543
#else /* not __GLIBC__ */
1544
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1545
alphasort);
1546
#endif /* not __GLIBC__ */
1547
if(numhooks == -1){
1548
perror_plus("scandir");
1549
return;
1550
}
1551
struct dirent *direntry;
1552
int ret;
1553
int devnull = open("/dev/null", O_RDONLY);
1554
for(int i = 0; i < numhooks; i++){
1555
direntry = direntries[i];
1556
if(debug){
1557
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1558
direntry->d_name);
1559
}
1560
pid_t hook_pid = fork();
1561
if(hook_pid == 0){
1562
/* Child */
1563
/* Raise privileges */
1564
errno = raise_privileges_permanently();
1565
if(errno != 0){
1566
perror_plus("Failed to raise privileges");
1567
_exit(EX_NOPERM);
1568
}
1569
/* Set group */
1570
errno = 0;
1571
ret = setgid(0);
1572
if(ret == -1){
1573
perror_plus("setgid");
1574
_exit(EX_NOPERM);
1575
}
1576
/* Reset supplementary groups */
1577
errno = 0;
1578
ret = setgroups(0, NULL);
1579
if(ret == -1){
1580
perror_plus("setgroups");
1581
_exit(EX_NOPERM);
1582
}
1583
ret = dup2(devnull, STDIN_FILENO);
1584
if(ret == -1){
1585
perror_plus("dup2(devnull, STDIN_FILENO)");
1586
_exit(EX_OSERR);
1587
}
1588
ret = close(devnull);
1589
if(ret == -1){
1590
perror_plus("close");
1591
_exit(EX_OSERR);
1592
}
1593
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1594
if(ret == -1){
1595
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1596
_exit(EX_OSERR);
1597
}
1598
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1599
if(ret == -1){
1600
perror_plus("setenv");
1601
_exit(EX_OSERR);
1602
}
1603
ret = setenv("DEVICE", interface, 1);
1604
if(ret == -1){
1605
perror_plus("setenv");
1606
_exit(EX_OSERR);
1607
}
1608
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1609
if(ret == -1){
1610
perror_plus("setenv");
1611
_exit(EX_OSERR);
1612
}
1613
ret = setenv("MODE", mode, 1);
1614
if(ret == -1){
1615
perror_plus("setenv");
1616
_exit(EX_OSERR);
1617
}
1618
char *delaystring;
1619
ret = asprintf(&delaystring, "%f", (double)delay);
1620
if(ret == -1){
1621
perror_plus("asprintf");
1622
_exit(EX_OSERR);
1623
}
1624
ret = setenv("DELAY", delaystring, 1);
1625
if(ret == -1){
1626
free(delaystring);
1627
perror_plus("setenv");
1628
_exit(EX_OSERR);
1629
}
1630
free(delaystring);
1631
if(connect_to != NULL){
1632
ret = setenv("CONNECT", connect_to, 1);
1633
if(ret == -1){
1634
perror_plus("setenv");
1635
_exit(EX_OSERR);
1636
}
1637
}
1638
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1639
if(hook_fd == -1){
1640
perror_plus("openat");
1641
_exit(EXIT_FAILURE);
1642
}
1643
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1644
perror_plus("close");
1645
_exit(EXIT_FAILURE);
1646
}
1647
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1648
environ) == -1){
1649
perror_plus("fexecve");
1650
_exit(EXIT_FAILURE);
1651
}
1652
} else {
1653
int status;
1654
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1655
perror_plus("waitpid");
1656
free(direntry);
1657
continue;
1658
}
1659
if(WIFEXITED(status)){
1660
if(WEXITSTATUS(status) != 0){
1661
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1662
" with status %d\n", direntry->d_name,
1663
WEXITSTATUS(status));
1664
free(direntry);
1665
continue;
1666
}
1667
} else if(WIFSIGNALED(status)){
1668
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1669
" signal %d\n", direntry->d_name,
1670
WTERMSIG(status));
1671
free(direntry);
1672
continue;
1673
} else {
1674
fprintf_plus(stderr, "Warning: network hook \"%s\""
1675
" crashed\n", direntry->d_name);
1676
free(direntry);
1677
continue;
1678
}
1679
}
1680
if(debug){
1681
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1682
direntry->d_name);
1683
}
1684
free(direntry);
1685
}
1686
free(direntries);
1687
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1688
perror_plus("close");
1689
} else {
1690
hookdir_fd = -1;
1691
}
1692
close(devnull);
1693
}
1694
1695
__attribute__((nonnull, warn_unused_result))
1696
error_t bring_up_interface(const char *const interface,
1697
const float delay){
1698
error_t old_errno = errno;
1699
int ret;
1700
struct ifreq network;
1701
unsigned int if_index = if_nametoindex(interface);
1702
if(if_index == 0){
1703
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1704
errno = old_errno;
1705
return ENXIO;
1706
}
1707
1708
if(quit_now){
1709
errno = old_errno;
1710
return EINTR;
1711
}
1712
1713
if(not interface_is_up(interface)){
1714
error_t ret_errno = 0, ioctl_errno = 0;
1715
if(not get_flags(interface, &network)){
1716
ret_errno = errno;
1717
fprintf_plus(stderr, "Failed to get flags for interface "
1718
"\"%s\"\n", interface);
1719
errno = old_errno;
1720
return ret_errno;
1721
}
1722
network.ifr_flags |= IFF_UP; /* set flag */
1723
1724
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1725
if(sd == -1){
1726
ret_errno = errno;
1727
perror_plus("socket");
1728
errno = old_errno;
1729
return ret_errno;
1730
}
1731
1732
if(quit_now){
1733
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1734
if(ret == -1){
1735
perror_plus("close");
1736
}
1737
errno = old_errno;
1738
return EINTR;
1739
}
1740
1741
if(debug){
1742
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1743
interface);
1744
}
1745
1746
/* Raise privileges */
1747
ret_errno = raise_privileges();
1748
if(ret_errno != 0){
1749
errno = ret_errno;
1750
perror_plus("Failed to raise privileges");
1751
}
1752
1753
#ifdef __linux__
1754
int ret_linux;
1755
bool restore_loglevel = false;
1756
if(ret_errno == 0){
1757
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1758
messages about the network interface to mess up the prompt */
1759
ret_linux = klogctl(8, NULL, 5);
1760
if(ret_linux == -1){
1761
perror_plus("klogctl");
1762
} else {
1763
restore_loglevel = true;
1764
}
1765
}
1766
#endif /* __linux__ */
1767
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1768
ioctl_errno = errno;
1769
#ifdef __linux__
1770
if(restore_loglevel){
1771
ret_linux = klogctl(7, NULL, 0);
1772
if(ret_linux == -1){
1773
perror_plus("klogctl");
1774
}
1775
}
1776
#endif /* __linux__ */
1777
1778
/* If raise_privileges() succeeded above */
1779
if(ret_errno == 0){
1780
/* Lower privileges */
1781
ret_errno = lower_privileges();
1782
if(ret_errno != 0){
1783
errno = ret_errno;
1784
perror_plus("Failed to lower privileges");
1785
}
1786
}
1787
1788
/* Close the socket */
1789
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1790
if(ret == -1){
1791
perror_plus("close");
1792
}
1793
1794
if(ret_setflags == -1){
1795
errno = ioctl_errno;
1796
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1797
errno = old_errno;
1798
return ioctl_errno;
1799
}
1800
} else if(debug){
1801
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1802
interface);
1803
}
1804
1805
/* Sleep checking until interface is running.
1806
Check every 0.25s, up to total time of delay */
1807
for(int i=0; i < delay * 4; i++){
1808
if(interface_is_running(interface)){
1809
break;
1810
}
1811
struct timespec sleeptime = { .tv_nsec = 250000000 };
1812
ret = nanosleep(&sleeptime, NULL);
1813
if(ret == -1 and errno != EINTR){
1814
perror_plus("nanosleep");
1815
}
1816
}
1817
1818
errno = old_errno;
1819
return 0;
1820
}
1821
1822
__attribute__((nonnull, warn_unused_result))
1823
error_t take_down_interface(const char *const interface){
1824
error_t old_errno = errno;
1825
struct ifreq network;
1826
unsigned int if_index = if_nametoindex(interface);
1827
if(if_index == 0){
1828
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1829
errno = old_errno;
1830
return ENXIO;
1831
}
1832
if(interface_is_up(interface)){
1833
error_t ret_errno = 0, ioctl_errno = 0;
1834
if(not get_flags(interface, &network) and debug){
1835
ret_errno = errno;
1836
fprintf_plus(stderr, "Failed to get flags for interface "
1837
"\"%s\"\n", interface);
1838
errno = old_errno;
1839
return ret_errno;
1840
}
1841
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1842
1843
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1844
if(sd == -1){
1845
ret_errno = errno;
1846
perror_plus("socket");
1847
errno = old_errno;
1848
return ret_errno;
1849
}
1850
1851
if(debug){
1852
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1853
interface);
1854
}
1855
1856
/* Raise privileges */
1857
ret_errno = raise_privileges();
1858
if(ret_errno != 0){
1859
errno = ret_errno;
1860
perror_plus("Failed to raise privileges");
1861
}
1862
1863
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1864
ioctl_errno = errno;
1865
1866
/* If raise_privileges() succeeded above */
1867
if(ret_errno == 0){
1868
/* Lower privileges */
1869
ret_errno = lower_privileges();
1870
if(ret_errno != 0){
1871
errno = ret_errno;
1872
perror_plus("Failed to lower privileges");
1873
}
1874
}
1875
1876
/* Close the socket */
1877
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1878
if(ret == -1){
1879
perror_plus("close");
1880
}
1881
1882
if(ret_setflags == -1){
1883
errno = ioctl_errno;
1884
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1885
errno = old_errno;
1886
return ioctl_errno;
1887
}
1888
} else if(debug){
1889
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1890
interface);
1891
}
1892
1893
errno = old_errno;
1894
return 0;
1895
}
1896
1897
int main(int argc, char *argv[]){
1898
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1899
.priority = "SECURE256:!CTYPE-X.509:"
1900
"+CTYPE-OPENPGP", .current_server = NULL,
1901
.interfaces = NULL, .interfaces_size = 0 };
1902
AvahiSServiceBrowser *sb = NULL;
1903
error_t ret_errno;
1904
int ret;
1905
intmax_t tmpmax;
1906
char *tmp;
1907
int exitcode = EXIT_SUCCESS;
1908
char *interfaces_to_take_down = NULL;
1909
size_t interfaces_to_take_down_size = 0;
1910
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1911
char old_tempdir[] = "/tmp/mandosXXXXXX";
1912
char *tempdir = NULL;
1913
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1914
const char *seckey = PATHDIR "/" SECKEY;
1915
const char *pubkey = PATHDIR "/" PUBKEY;
1916
char *interfaces_hooks = NULL;
1917
1918
bool gnutls_initialized = false;
1919
bool gpgme_initialized = false;
1920
float delay = 2.5f;
1921
double retry_interval = 10; /* 10s between trying a server and
1922
retrying the same server again */
1923
1924
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1925
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1926
1927
uid = getuid();
1928
gid = getgid();
1929
1930
/* Lower any group privileges we might have, just to be safe */
1931
errno = 0;
1932
ret = setgid(gid);
1933
if(ret == -1){
1934
perror_plus("setgid");
1935
}
1936
1937
/* Lower user privileges (temporarily) */
1938
errno = 0;
1939
ret = seteuid(uid);
1940
if(ret == -1){
1941
perror_plus("seteuid");
1942
}
1943
1944
if(quit_now){
1945
goto end;
1946
}
1947
1948
{
1949
struct argp_option options[] = {
1950
{ .name = "debug", .key = 128,
1951
.doc = "Debug mode", .group = 3 },
1952
{ .name = "connect", .key = 'c',
1953
.arg = "ADDRESS:PORT",
1954
.doc = "Connect directly to a specific Mandos server",
1955
.group = 1 },
1956
{ .name = "interface", .key = 'i',
1957
.arg = "NAME",
1958
.doc = "Network interface that will be used to search for"
1959
" Mandos servers",
1960
.group = 1 },
1961
{ .name = "seckey", .key = 's',
1962
.arg = "FILE",
1963
.doc = "OpenPGP secret key file base name",
1964
.group = 1 },
1965
{ .name = "pubkey", .key = 'p',
1966
.arg = "FILE",
1967
.doc = "OpenPGP public key file base name",
1968
.group = 2 },
1969
{ .name = "dh-bits", .key = 129,
1970
.arg = "BITS",
1971
.doc = "Bit length of the prime number used in the"
1972
" Diffie-Hellman key exchange",
1973
.group = 2 },
1974
{ .name = "priority", .key = 130,
1975
.arg = "STRING",
1976
.doc = "GnuTLS priority string for the TLS handshake",
1977
.group = 1 },
1978
{ .name = "delay", .key = 131,
1979
.arg = "SECONDS",
1980
.doc = "Maximum delay to wait for interface startup",
1981
.group = 2 },
1982
{ .name = "retry", .key = 132,
1983
.arg = "SECONDS",
1984
.doc = "Retry interval used when denied by the Mandos server",
1985
.group = 2 },
1986
{ .name = "network-hook-dir", .key = 133,
1987
.arg = "DIR",
1988
.doc = "Directory where network hooks are located",
1989
.group = 2 },
1990
/*
1991
* These reproduce what we would get without ARGP_NO_HELP
1992
*/
1993
{ .name = "help", .key = '?',
1994
.doc = "Give this help list", .group = -1 },
1995
{ .name = "usage", .key = -3,
1996
.doc = "Give a short usage message", .group = -1 },
1997
{ .name = "version", .key = 'V',
1998
.doc = "Print program version", .group = -1 },
1999
{ .name = NULL }
2000
};
2001
2002
error_t parse_opt(int key, char *arg,
2003
struct argp_state *state){
2004
errno = 0;
2005
switch(key){
2006
case 128: /* --debug */
2007
debug = true;
2008
break;
2009
case 'c': /* --connect */
2010
connect_to = arg;
2011
break;
2012
case 'i': /* --interface */
2013
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2014
arg, (int)',');
2015
if(ret_errno != 0){
2016
argp_error(state, "%s", strerror(ret_errno));
2017
}
2018
break;
2019
case 's': /* --seckey */
2020
seckey = arg;
2021
break;
2022
case 'p': /* --pubkey */
2023
pubkey = arg;
2024
break;
2025
case 129: /* --dh-bits */
2026
errno = 0;
2027
tmpmax = strtoimax(arg, &tmp, 10);
2028
if(errno != 0 or tmp == arg or *tmp != '\0'
2029
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2030
argp_error(state, "Bad number of DH bits");
2031
}
2032
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2033
break;
2034
case 130: /* --priority */
2035
mc.priority = arg;
2036
break;
2037
case 131: /* --delay */
2038
errno = 0;
2039
delay = strtof(arg, &tmp);
2040
if(errno != 0 or tmp == arg or *tmp != '\0'){
2041
argp_error(state, "Bad delay");
2042
}
2043
case 132: /* --retry */
2044
errno = 0;
2045
retry_interval = strtod(arg, &tmp);
2046
if(errno != 0 or tmp == arg or *tmp != '\0'
2047
or (retry_interval * 1000) > INT_MAX
2048
or retry_interval < 0){
2049
argp_error(state, "Bad retry interval");
2050
}
2051
break;
2052
case 133: /* --network-hook-dir */
2053
hookdir = arg;
2054
break;
2055
/*
2056
* These reproduce what we would get without ARGP_NO_HELP
2057
*/
2058
case '?': /* --help */
2059
argp_state_help(state, state->out_stream,
2060
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2061
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2062
case -3: /* --usage */
2063
argp_state_help(state, state->out_stream,
2064
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2065
case 'V': /* --version */
2066
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2067
exit(argp_err_exit_status);
2068
break;
2069
default:
2070
return ARGP_ERR_UNKNOWN;
2071
}
2072
return errno;
2073
}
2074
2075
struct argp argp = { .options = options, .parser = parse_opt,
2076
.args_doc = "",
2077
.doc = "Mandos client -- Get and decrypt"
2078
" passwords from a Mandos server" };
2079
ret = argp_parse(&argp, argc, argv,
2080
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2081
switch(ret){
2082
case 0:
2083
break;
2084
case ENOMEM:
2085
default:
2086
errno = ret;
2087
perror_plus("argp_parse");
2088
exitcode = EX_OSERR;
2089
goto end;
2090
case EINVAL:
2091
exitcode = EX_USAGE;
2092
goto end;
2093
}
2094
}
2095
2096
{
2097
/* Work around Debian bug #633582:
2098
<http://bugs.debian.org/633582> */
2099
2100
/* Re-raise privileges */
2101
ret_errno = raise_privileges();
2102
if(ret_errno != 0){
2103
errno = ret_errno;
2104
perror_plus("Failed to raise privileges");
2105
} else {
2106
struct stat st;
2107
2108
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2109
int seckey_fd = open(seckey, O_RDONLY);
2110
if(seckey_fd == -1){
2111
perror_plus("open");
2112
} else {
2113
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2114
if(ret == -1){
2115
perror_plus("fstat");
2116
} else {
2117
if(S_ISREG(st.st_mode)
2118
and st.st_uid == 0 and st.st_gid == 0){
2119
ret = fchown(seckey_fd, uid, gid);
2120
if(ret == -1){
2121
perror_plus("fchown");
2122
}
2123
}
2124
}
2125
TEMP_FAILURE_RETRY(close(seckey_fd));
2126
}
2127
}
2128
2129
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2130
int pubkey_fd = open(pubkey, O_RDONLY);
2131
if(pubkey_fd == -1){
2132
perror_plus("open");
2133
} else {
2134
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2135
if(ret == -1){
2136
perror_plus("fstat");
2137
} else {
2138
if(S_ISREG(st.st_mode)
2139
and st.st_uid == 0 and st.st_gid == 0){
2140
ret = fchown(pubkey_fd, uid, gid);
2141
if(ret == -1){
2142
perror_plus("fchown");
2143
}
2144
}
2145
}
2146
TEMP_FAILURE_RETRY(close(pubkey_fd));
2147
}
2148
}
2149
2150
/* Lower privileges */
2151
ret_errno = lower_privileges();
2152
if(ret_errno != 0){
2153
errno = ret_errno;
2154
perror_plus("Failed to lower privileges");
2155
}
2156
}
2157
}
2158
2159
/* Remove invalid interface names (except "none") */
2160
{
2161
char *interface = NULL;
2162
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2163
interface))){
2164
if(strcmp(interface, "none") != 0
2165
and if_nametoindex(interface) == 0){
2166
if(interface[0] != '\0'){
2167
fprintf_plus(stderr, "Not using nonexisting interface"
2168
" \"%s\"\n", interface);
2169
}
2170
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2171
interface = NULL;
2172
}
2173
}
2174
}
2175
2176
/* Run network hooks */
2177
{
2178
if(mc.interfaces != NULL){
2179
interfaces_hooks = malloc(mc.interfaces_size);
2180
if(interfaces_hooks == NULL){
2181
perror_plus("malloc");
2182
goto end;
2183
}
2184
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2185
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2186
}
2187
run_network_hooks("start", interfaces_hooks != NULL ?
2188
interfaces_hooks : "", delay);
2189
}
2190
2191
if(not debug){
2192
avahi_set_log_function(empty_log);
2193
}
2194
2195
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2196
from the signal handler */
2197
/* Initialize the pseudo-RNG for Avahi */
2198
srand((unsigned int) time(NULL));
2199
simple_poll = avahi_simple_poll_new();
2200
if(simple_poll == NULL){
2201
fprintf_plus(stderr,
2202
"Avahi: Failed to create simple poll object.\n");
2203
exitcode = EX_UNAVAILABLE;
2204
goto end;
2205
}
2206
2207
sigemptyset(&sigterm_action.sa_mask);
2208
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2209
if(ret == -1){
2210
perror_plus("sigaddset");
2211
exitcode = EX_OSERR;
2212
goto end;
2213
}
2214
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2215
if(ret == -1){
2216
perror_plus("sigaddset");
2217
exitcode = EX_OSERR;
2218
goto end;
2219
}
2220
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2221
if(ret == -1){
2222
perror_plus("sigaddset");
2223
exitcode = EX_OSERR;
2224
goto end;
2225
}
2226
/* Need to check if the handler is SIG_IGN before handling:
2227
| [[info:libc:Initial Signal Actions]] |
2228
| [[info:libc:Basic Signal Handling]] |
2229
*/
2230
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2231
if(ret == -1){
2232
perror_plus("sigaction");
2233
return EX_OSERR;
2234
}
2235
if(old_sigterm_action.sa_handler != SIG_IGN){
2236
ret = sigaction(SIGINT, &sigterm_action, NULL);
2237
if(ret == -1){
2238
perror_plus("sigaction");
2239
exitcode = EX_OSERR;
2240
goto end;
2241
}
2242
}
2243
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2244
if(ret == -1){
2245
perror_plus("sigaction");
2246
return EX_OSERR;
2247
}
2248
if(old_sigterm_action.sa_handler != SIG_IGN){
2249
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2250
if(ret == -1){
2251
perror_plus("sigaction");
2252
exitcode = EX_OSERR;
2253
goto end;
2254
}
2255
}
2256
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2257
if(ret == -1){
2258
perror_plus("sigaction");
2259
return EX_OSERR;
2260
}
2261
if(old_sigterm_action.sa_handler != SIG_IGN){
2262
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2263
if(ret == -1){
2264
perror_plus("sigaction");
2265
exitcode = EX_OSERR;
2266
goto end;
2267
}
2268
}
2269
2270
/* If no interfaces were specified, make a list */
2271
if(mc.interfaces == NULL){
2272
struct dirent **direntries = NULL;
2273
/* Look for any good interfaces */
2274
ret = scandir(sys_class_net, &direntries, good_interface,
2275
alphasort);
2276
if(ret >= 1){
2277
/* Add all found interfaces to interfaces list */
2278
for(int i = 0; i < ret; ++i){
2279
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2280
direntries[i]->d_name);
2281
if(ret_errno != 0){
2282
errno = ret_errno;
2283
perror_plus("argz_add");
2284
free(direntries[i]);
2285
continue;
2286
}
2287
if(debug){
2288
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2289
direntries[i]->d_name);
2290
}
2291
free(direntries[i]);
2292
}
2293
free(direntries);
2294
} else {
2295
if(ret == 0){
2296
free(direntries);
2297
}
2298
fprintf_plus(stderr, "Could not find a network interface\n");
2299
exitcode = EXIT_FAILURE;
2300
goto end;
2301
}
2302
}
2303
2304
/* Bring up interfaces which are down, and remove any "none"s */
2305
{
2306
char *interface = NULL;
2307
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2308
interface))){
2309
/* If interface name is "none", stop bringing up interfaces.
2310
Also remove all instances of "none" from the list */
2311
if(strcmp(interface, "none") == 0){
2312
argz_delete(&mc.interfaces, &mc.interfaces_size,
2313
interface);
2314
interface = NULL;
2315
while((interface = argz_next(mc.interfaces,
2316
mc.interfaces_size, interface))){
2317
if(strcmp(interface, "none") == 0){
2318
argz_delete(&mc.interfaces, &mc.interfaces_size,
2319
interface);
2320
interface = NULL;
2321
}
2322
}
2323
break;
2324
}
2325
bool interface_was_up = interface_is_up(interface);
2326
errno = bring_up_interface(interface, delay);
2327
if(not interface_was_up){
2328
if(errno != 0){
2329
perror_plus("Failed to bring up interface");
2330
} else {
2331
errno = argz_add(&interfaces_to_take_down,
2332
&interfaces_to_take_down_size,
2333
interface);
2334
if(errno != 0){
2335
perror_plus("argz_add");
2336
}
2337
}
2338
}
2339
}
2340
if(debug and (interfaces_to_take_down == NULL)){
2341
fprintf_plus(stderr, "No interfaces were brought up\n");
2342
}
2343
}
2344
2345
/* If we only got one interface, explicitly use only that one */
2346
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2347
if(debug){
2348
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2349
mc.interfaces);
2350
}
2351
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2352
}
2353
2354
if(quit_now){
2355
goto end;
2356
}
2357
2358
ret = init_gnutls_global(pubkey, seckey, &mc);
2359
if(ret == -1){
2360
fprintf_plus(stderr, "init_gnutls_global failed\n");
2361
exitcode = EX_UNAVAILABLE;
2362
goto end;
2363
} else {
2364
gnutls_initialized = true;
2365
}
2366
2367
if(quit_now){
2368
goto end;
2369
}
2370
2371
/* Try /run/tmp before /tmp */
2372
tempdir = mkdtemp(run_tempdir);
2373
if(tempdir == NULL and errno == ENOENT){
2374
if(debug){
2375
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2376
run_tempdir, old_tempdir);
2377
}
2378
tempdir = mkdtemp(old_tempdir);
2379
}
2380
if(tempdir == NULL){
2381
perror_plus("mkdtemp");
2382
goto end;
2383
}
2384
2385
if(quit_now){
2386
goto end;
2387
}
2388
2389
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2390
fprintf_plus(stderr, "init_gpgme failed\n");
2391
exitcode = EX_UNAVAILABLE;
2392
goto end;
2393
} else {
2394
gpgme_initialized = true;
2395
}
2396
2397
if(quit_now){
2398
goto end;
2399
}
2400
2401
if(connect_to != NULL){
2402
/* Connect directly, do not use Zeroconf */
2403
/* (Mainly meant for debugging) */
2404
char *address = strrchr(connect_to, ':');
2405
2406
if(address == NULL){
2407
fprintf_plus(stderr, "No colon in address\n");
2408
exitcode = EX_USAGE;
2409
goto end;
2410
}
2411
2412
if(quit_now){
2413
goto end;
2414
}
2415
2416
in_port_t port;
2417
errno = 0;
2418
tmpmax = strtoimax(address+1, &tmp, 10);
2419
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2420
or tmpmax != (in_port_t)tmpmax){
2421
fprintf_plus(stderr, "Bad port number\n");
2422
exitcode = EX_USAGE;
2423
goto end;
2424
}
2425
2426
if(quit_now){
2427
goto end;
2428
}
2429
2430
port = (in_port_t)tmpmax;
2431
*address = '\0';
2432
/* Colon in address indicates IPv6 */
2433
int af;
2434
if(strchr(connect_to, ':') != NULL){
2435
af = AF_INET6;
2436
/* Accept [] around IPv6 address - see RFC 5952 */
2437
if(connect_to[0] == '[' and address[-1] == ']')
2438
{
2439
connect_to++;
2440
address[-1] = '\0';
2441
}
2442
} else {
2443
af = AF_INET;
2444
}
2445
address = connect_to;
2446
2447
if(quit_now){
2448
goto end;
2449
}
2450
2451
while(not quit_now){
2452
ret = start_mandos_communication(address, port, if_index, af,
2453
&mc);
2454
if(quit_now or ret == 0){
2455
break;
2456
}
2457
if(debug){
2458
fprintf_plus(stderr, "Retrying in %d seconds\n",
2459
(int)retry_interval);
2460
}
2461
sleep((unsigned int)retry_interval);
2462
}
2463
2464
if(not quit_now){
2465
exitcode = EXIT_SUCCESS;
2466
}
2467
2468
goto end;
2469
}
2470
2471
if(quit_now){
2472
goto end;
2473
}
2474
2475
{
2476
AvahiServerConfig config;
2477
/* Do not publish any local Zeroconf records */
2478
avahi_server_config_init(&config);
2479
config.publish_hinfo = 0;
2480
config.publish_addresses = 0;
2481
config.publish_workstation = 0;
2482
config.publish_domain = 0;
2483
2484
/* Allocate a new server */
2485
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2486
&config, NULL, NULL, &ret_errno);
2487
2488
/* Free the Avahi configuration data */
2489
avahi_server_config_free(&config);
2490
}
2491
2492
/* Check if creating the Avahi server object succeeded */
2493
if(mc.server == NULL){
2494
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2495
avahi_strerror(ret_errno));
2496
exitcode = EX_UNAVAILABLE;
2497
goto end;
2498
}
2499
2500
if(quit_now){
2501
goto end;
2502
}
2503
2504
/* Create the Avahi service browser */
2505
sb = avahi_s_service_browser_new(mc.server, if_index,
2506
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2507
NULL, 0, browse_callback,
2508
(void *)&mc);
2509
if(sb == NULL){
2510
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2511
avahi_strerror(avahi_server_errno(mc.server)));
2512
exitcode = EX_UNAVAILABLE;
2513
goto end;
2514
}
2515
2516
if(quit_now){
2517
goto end;
2518
}
2519
2520
/* Run the main loop */
2521
2522
if(debug){
2523
fprintf_plus(stderr, "Starting Avahi loop search\n");
2524
}
2525
2526
ret = avahi_loop_with_timeout(simple_poll,
2527
(int)(retry_interval * 1000), &mc);
2528
if(debug){
2529
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2530
(ret == 0) ? "successfully" : "with error");
2531
}
2532
2533
end:
2534
2535
if(debug){
2536
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2537
}
2538
2539
/* Cleanup things */
2540
free(mc.interfaces);
2541
2542
if(sb != NULL)
2543
avahi_s_service_browser_free(sb);
2544
2545
if(mc.server != NULL)
2546
avahi_server_free(mc.server);
2547
2548
if(simple_poll != NULL)
2549
avahi_simple_poll_free(simple_poll);
2550
2551
if(gnutls_initialized){
2552
gnutls_certificate_free_credentials(mc.cred);
2553
gnutls_global_deinit();
2554
gnutls_dh_params_deinit(mc.dh_params);
2555
}
2556
2557
if(gpgme_initialized){
2558
gpgme_release(mc.ctx);
2559
}
2560
2561
/* Cleans up the circular linked list of Mandos servers the client
2562
has seen */
2563
if(mc.current_server != NULL){
2564
mc.current_server->prev->next = NULL;
2565
while(mc.current_server != NULL){
2566
server *next = mc.current_server->next;
2567
#ifdef __GNUC__
2568
#pragma GCC diagnostic push
2569
#pragma GCC diagnostic ignored "-Wcast-qual"
2570
#endif
2571
free((char *)(mc.current_server->ip));
2572
#ifdef __GNUC__
2573
#pragma GCC diagnostic pop
2574
#endif
2575
free(mc.current_server);
2576
mc.current_server = next;
2577
}
2578
}
2579
2580
/* Re-raise privileges */
2581
{
2582
ret_errno = raise_privileges();
2583
if(ret_errno != 0){
2584
errno = ret_errno;
2585
perror_plus("Failed to raise privileges");
2586
} else {
2587
2588
/* Run network hooks */
2589
run_network_hooks("stop", interfaces_hooks != NULL ?
2590
interfaces_hooks : "", delay);
2591
2592
/* Take down the network interfaces which were brought up */
2593
{
2594
char *interface = NULL;
2595
while((interface=argz_next(interfaces_to_take_down,
2596
interfaces_to_take_down_size,
2597
interface))){
2598
ret_errno = take_down_interface(interface);
2599
if(ret_errno != 0){
2600
errno = ret_errno;
2601
perror_plus("Failed to take down interface");
2602
}
2603
}
2604
if(debug and (interfaces_to_take_down == NULL)){
2605
fprintf_plus(stderr, "No interfaces needed to be taken"
2606
" down\n");
2607
}
2608
}
2609
}
2610
2611
ret_errno = lower_privileges_permanently();
2612
if(ret_errno != 0){
2613
errno = ret_errno;
2614
perror_plus("Failed to lower privileges permanently");
2615
}
2616
}
2617
2618
free(interfaces_to_take_down);
2619
free(interfaces_hooks);
2620
2621
/* Removes the GPGME temp directory and all files inside */
2622
if(tempdir != NULL){
2623
struct dirent **direntries = NULL;
2624
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2625
O_NOFOLLOW));
2626
if(tempdir_fd == -1){
2627
perror_plus("open");
2628
} else {
2629
#ifdef __GLIBC__
2630
#if __GLIBC_PREREQ(2, 15)
2631
int numentries = scandirat(tempdir_fd, ".", &direntries,
2632
notdotentries, alphasort);
2633
#else /* not __GLIBC_PREREQ(2, 15) */
2634
int numentries = scandir(tempdir, &direntries, notdotentries,
2635
alphasort);
2636
#endif /* not __GLIBC_PREREQ(2, 15) */
2637
#else /* not __GLIBC__ */
2638
int numentries = scandir(tempdir, &direntries, notdotentries,
2639
alphasort);
2640
#endif /* not __GLIBC__ */
2641
if(numentries >= 0){
2642
for(int i = 0; i < numentries; i++){
2643
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2644
if(ret == -1){
2645
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2646
" \"%s\", 0): %s\n", tempdir,
2647
direntries[i]->d_name, strerror(errno));
2648
}
2649
free(direntries[i]);
2650
}
2651
2652
/* need to clean even if 0 because man page doesn't specify */
2653
free(direntries);
2654
if(numentries == -1){
2655
perror_plus("scandir");
2656
}
2657
ret = rmdir(tempdir);
2658
if(ret == -1 and errno != ENOENT){
2659
perror_plus("rmdir");
2660
}
2661
}
2662
TEMP_FAILURE_RETRY(close(tempdir_fd));
2663
}
2664
}
2665
2666
if(quit_now){
2667
sigemptyset(&old_sigterm_action.sa_mask);
2668
old_sigterm_action.sa_handler = SIG_DFL;
2669
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2670
&old_sigterm_action,
2671
NULL));
2672
if(ret == -1){
2673
perror_plus("sigaction");
2674
}
2675
do {
2676
ret = raise(signal_received);
2677
} while(ret != 0 and errno == EINTR);
2678
if(ret != 0){
2679
perror_plus("raise");
2680
abort();
2681
}
2682
TEMP_FAILURE_RETRY(pause());
2683
}
2684
2685
return exitcode;
2686
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0