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- Committer: Teddy Hogeborn
- Date: 2008-07-19 18:43:24 UTC
- Revision ID: teddy@fukt.bsnet.se-20080719184324-iwhoa5in75xa0u2u
* mandos-clients.conf ([foo]/dn, [foo]/password, [braxen_client]/dn,
[braxen_client]/password): Removed.
([foo]/fingerprint, [braxen_client]/fingerprint): New.
([foo]/checker): New.
([foo]/secfile): New.
([braxen_client]/secret): New.
* server.py: New "--debug" option to set debug flag. Removed "cert",
"key", "ca", "crl", and "cred" variables. Added default
value for "checker" config file setting. Do not pass
credentials to IPv6_TCPServer constructor.
(debug): New global debug flag. Used by most debugging output code.
(Client.__init__): Keyword argument "dn" replaced by "fingerprint",
"password" renamed to "secret", and "passfile"
renamed to "secfile". New keyword argument
"checker". All callers changed.
(Client.dn): Removed.
(Client.fingerprint): New.
(Client.password): Renamed to "secret"; all users changed.
(Client.passfile): Renamed to "secfile"; all users changed.
(Client.timeout, Client.interval): Changed to be properties; now
automatically updates the
"_timeout_milliseconds" and
"_interval_milliseconds" values.
(Client.timeout_milliseconds): Renamed to "_timeout_milliseconds".
(Client.interval_milliseconds): Renamed to "_interval_milliseconds".
(Client.check_command): New.
(Client.start_checker): Use the new "check_command" attribute.
(peer_certificate, fingerprint): New functions.
(tcp_handler.handle): Use ClientSession with empty credentials
object instead of ServerSession. Set gnutls
priority string. Do not verify peer. Use
fingerprint instead of DN when searching for
clients. Bug fix: Loop sending data so even large
secret data strings are sent.
(IPv6_TCPServer.credentials): Removed.
(if_nametoindex): Do not import ctypes since that is now imported
globally.
[braxen_client]/password): Removed.
([foo]/fingerprint, [braxen_client]/fingerprint): New.
([foo]/checker): New.
([foo]/secfile): New.
([braxen_client]/secret): New.
* server.py: New "--debug" option to set debug flag. Removed "cert",
"key", "ca", "crl", and "cred" variables. Added default
value for "checker" config file setting. Do not pass
credentials to IPv6_TCPServer constructor.
(debug): New global debug flag. Used by most debugging output code.
(Client.__init__): Keyword argument "dn" replaced by "fingerprint",
"password" renamed to "secret", and "passfile"
renamed to "secfile". New keyword argument
"checker". All callers changed.
(Client.dn): Removed.
(Client.fingerprint): New.
(Client.password): Renamed to "secret"; all users changed.
(Client.passfile): Renamed to "secfile"; all users changed.
(Client.timeout, Client.interval): Changed to be properties; now
automatically updates the
"_timeout_milliseconds" and
"_interval_milliseconds" values.
(Client.timeout_milliseconds): Renamed to "_timeout_milliseconds".
(Client.interval_milliseconds): Renamed to "_interval_milliseconds".
(Client.check_command): New.
(Client.start_checker): Use the new "check_command" attribute.
(peer_certificate, fingerprint): New functions.
(tcp_handler.handle): Use ClientSession with empty credentials
object instead of ServerSession. Set gnutls
priority string. Do not verify peer. Use
fingerprint instead of DN when searching for
clients. Bug fix: Loop sending data so even large
secret data strings are sent.
(IPv6_TCPServer.credentials): Removed.
(if_nametoindex): Do not import ctypes since that is now imported
globally.
- files added:
- 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
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
38
#endif
39
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
strtof(), abort() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
59
getnameinfo() */
60
#include <fcntl.h> /* open() */
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
#include <arpa/inet.h> /* inet_pton(), htons() */
78
#include <iso646.h> /* not, or, and */
79
#include <argp.h> /* struct argp_option, error_t, struct
80
argp_state, struct argp,
81
argp_parse(), ARGP_KEY_ARG,
82
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
83
#include <signal.h> /* sigemptyset(), sigaddset(),
84
sigaction(), SIGTERM, sig_atomic_t,
85
raise() */
86
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
87
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
88
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
89
WEXITSTATUS(), WTERMSIG() */
90
#include <grp.h> /* setgroups() */
91
#include <argz.h> /* argz_add_sep(), argz_next(),
92
argz_delete(), argz_append(),
93
argz_stringify(), argz_add(),
94
argz_count() */
95
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
96
EAI_SYSTEM, gai_strerror() */
97
98
#ifdef __linux__
99
#include <sys/klog.h> /* klogctl() */
100
#endif /* __linux__ */
101
102
/* Avahi */
103
/* All Avahi types, constants and functions
104
Avahi*, avahi_*,
105
AVAHI_* */
106
#include <avahi-core/core.h>
107
#include <avahi-core/lookup.h>
108
#include <avahi-core/log.h>
109
#include <avahi-common/simple-watch.h>
110
#include <avahi-common/malloc.h>
111
#include <avahi-common/error.h>
112
113
/* GnuTLS */
114
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
115
functions:
116
gnutls_*
117
init_gnutls_session(),
118
GNUTLS_* */
119
#include <gnutls/openpgp.h>
120
/* gnutls_certificate_set_openpgp_key_file(),
121
GNUTLS_OPENPGP_FMT_BASE64 */
122
123
/* GPGME */
124
#include <gpgme.h> /* All GPGME types, constants and
125
functions:
126
gpgme_*
127
GPGME_PROTOCOL_OpenPGP,
128
GPG_ERR_NO_* */
129
130
#define BUFFER_SIZE 256
131
132
#define PATHDIR "/conf/conf.d/mandos"
133
#define SECKEY "seckey.txt"
134
#define PUBKEY "pubkey.txt"
135
#define HOOKDIR "/lib/mandos/network-hooks.d"
136
137
bool debug = false;
138
static const char mandos_protocol_version[] = "1";
139
const char *argp_program_version = "mandos-client " VERSION;
140
const char *argp_program_bug_address = "<mandos@recompile.se>";
141
static const char sys_class_net[] = "/sys/class/net";
142
char *connect_to = NULL;
143
const char *hookdir = HOOKDIR;
144
uid_t uid = 65534;
145
gid_t gid = 65534;
146
147
/* Doubly linked list that need to be circularly linked when used */
148
typedef struct server{
149
const char *ip;
150
in_port_t port;
151
AvahiIfIndex if_index;
152
int af;
153
struct timespec last_seen;
154
struct server *next;
155
struct server *prev;
156
} server;
157
158
/* Used for passing in values through the Avahi callback functions */
159
typedef struct {
160
AvahiServer *server;
161
gnutls_certificate_credentials_t cred;
162
unsigned int dh_bits;
163
gnutls_dh_params_t dh_params;
164
const char *priority;
165
gpgme_ctx_t ctx;
166
server *current_server;
167
char *interfaces;
168
size_t interfaces_size;
169
} mandos_context;
170
171
/* global so signal handler can reach it*/
172
AvahiSimplePoll *simple_poll;
173
174
sig_atomic_t quit_now = 0;
175
int signal_received = 0;
176
177
/* Function to use when printing errors */
178
void perror_plus(const char *print_text){
179
int e = errno;
180
fprintf(stderr, "Mandos plugin %s: ",
181
program_invocation_short_name);
182
errno = e;
183
perror(print_text);
184
}
185
186
__attribute__((format (gnu_printf, 2, 3), nonnull))
187
int fprintf_plus(FILE *stream, const char *format, ...){
188
va_list ap;
189
va_start (ap, format);
190
191
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
192
program_invocation_short_name));
193
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
194
}
195
196
/*
197
* Make additional room in "buffer" for at least BUFFER_SIZE more
198
* bytes. "buffer_capacity" is how much is currently allocated,
199
* "buffer_length" is how much is already used.
200
*/
201
__attribute__((nonnull, warn_unused_result))
202
size_t incbuffer(char **buffer, size_t buffer_length,
203
size_t buffer_capacity){
204
if(buffer_length + BUFFER_SIZE > buffer_capacity){
205
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
206
if(new_buf == NULL){
207
int old_errno = errno;
208
free(*buffer);
209
errno = old_errno;
210
*buffer = NULL;
211
return 0;
212
}
213
*buffer = new_buf;
214
buffer_capacity += BUFFER_SIZE;
215
}
216
return buffer_capacity;
217
}
218
219
/* Add server to set of servers to retry periodically */
220
__attribute__((nonnull, warn_unused_result))
221
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
222
int af, server **current_server){
223
int ret;
224
server *new_server = malloc(sizeof(server));
225
if(new_server == NULL){
226
perror_plus("malloc");
227
return false;
228
}
229
*new_server = (server){ .ip = strdup(ip),
230
.port = port,
231
.if_index = if_index,
232
.af = af };
233
if(new_server->ip == NULL){
234
perror_plus("strdup");
235
return false;
236
}
237
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
238
if(ret == -1){
239
perror_plus("clock_gettime");
240
return false;
241
}
242
/* Special case of first server */
243
if(*current_server == NULL){
244
new_server->next = new_server;
245
new_server->prev = new_server;
246
*current_server = new_server;
247
} else {
248
/* Place the new server last in the list */
249
new_server->next = *current_server;
250
new_server->prev = (*current_server)->prev;
251
new_server->prev->next = new_server;
252
(*current_server)->prev = new_server;
253
}
254
return true;
255
}
256
257
/*
258
* Initialize GPGME.
259
*/
260
__attribute__((nonnull, warn_unused_result))
261
static bool init_gpgme(const char * const seckey,
262
const char * const pubkey,
263
const char * const tempdir,
264
mandos_context *mc){
265
gpgme_error_t rc;
266
gpgme_engine_info_t engine_info;
267
268
/*
269
* Helper function to insert pub and seckey to the engine keyring.
270
*/
271
bool import_key(const char * const filename){
272
int ret;
273
int fd;
274
gpgme_data_t pgp_data;
275
276
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
277
if(fd == -1){
278
perror_plus("open");
279
return false;
280
}
281
282
rc = gpgme_data_new_from_fd(&pgp_data, fd);
283
if(rc != GPG_ERR_NO_ERROR){
284
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
286
return false;
287
}
288
289
rc = gpgme_op_import(mc->ctx, pgp_data);
290
if(rc != GPG_ERR_NO_ERROR){
291
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
293
return false;
294
}
295
296
ret = (int)TEMP_FAILURE_RETRY(close(fd));
297
if(ret == -1){
298
perror_plus("close");
299
}
300
gpgme_data_release(pgp_data);
301
return true;
302
}
303
304
if(debug){
305
fprintf_plus(stderr, "Initializing GPGME\n");
306
}
307
308
/* Init GPGME */
309
gpgme_check_version(NULL);
310
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
311
if(rc != GPG_ERR_NO_ERROR){
312
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
313
gpgme_strsource(rc), gpgme_strerror(rc));
314
return false;
315
}
316
317
/* Set GPGME home directory for the OpenPGP engine only */
318
rc = gpgme_get_engine_info(&engine_info);
319
if(rc != GPG_ERR_NO_ERROR){
320
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
321
gpgme_strsource(rc), gpgme_strerror(rc));
322
return false;
323
}
324
while(engine_info != NULL){
325
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
326
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
327
engine_info->file_name, tempdir);
328
break;
329
}
330
engine_info = engine_info->next;
331
}
332
if(engine_info == NULL){
333
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
334
tempdir);
335
return false;
336
}
337
338
/* Create new GPGME "context" */
339
rc = gpgme_new(&(mc->ctx));
340
if(rc != GPG_ERR_NO_ERROR){
341
fprintf_plus(stderr, "Mandos plugin mandos-client: "
342
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
343
gpgme_strerror(rc));
344
return false;
345
}
346
347
if(not import_key(pubkey) or not import_key(seckey)){
348
return false;
349
}
350
351
return true;
352
}
353
354
/*
355
* Decrypt OpenPGP data.
356
* Returns -1 on error
357
*/
358
__attribute__((nonnull, warn_unused_result))
359
static ssize_t pgp_packet_decrypt(const char *cryptotext,
360
size_t crypto_size,
361
char **plaintext,
362
mandos_context *mc){
363
gpgme_data_t dh_crypto, dh_plain;
364
gpgme_error_t rc;
365
ssize_t ret;
366
size_t plaintext_capacity = 0;
367
ssize_t plaintext_length = 0;
368
369
if(debug){
370
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
371
}
372
373
/* Create new GPGME data buffer from memory cryptotext */
374
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
375
0);
376
if(rc != GPG_ERR_NO_ERROR){
377
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
378
gpgme_strsource(rc), gpgme_strerror(rc));
379
return -1;
380
}
381
382
/* Create new empty GPGME data buffer for the plaintext */
383
rc = gpgme_data_new(&dh_plain);
384
if(rc != GPG_ERR_NO_ERROR){
385
fprintf_plus(stderr, "Mandos plugin mandos-client: "
386
"bad gpgme_data_new: %s: %s\n",
387
gpgme_strsource(rc), gpgme_strerror(rc));
388
gpgme_data_release(dh_crypto);
389
return -1;
390
}
391
392
/* Decrypt data from the cryptotext data buffer to the plaintext
393
data buffer */
394
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
395
if(rc != GPG_ERR_NO_ERROR){
396
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
397
gpgme_strsource(rc), gpgme_strerror(rc));
398
plaintext_length = -1;
399
if(debug){
400
gpgme_decrypt_result_t result;
401
result = gpgme_op_decrypt_result(mc->ctx);
402
if(result == NULL){
403
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
404
} else {
405
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
406
result->unsupported_algorithm);
407
fprintf_plus(stderr, "Wrong key usage: %u\n",
408
result->wrong_key_usage);
409
if(result->file_name != NULL){
410
fprintf_plus(stderr, "File name: %s\n", result->file_name);
411
}
412
gpgme_recipient_t recipient;
413
recipient = result->recipients;
414
while(recipient != NULL){
415
fprintf_plus(stderr, "Public key algorithm: %s\n",
416
gpgme_pubkey_algo_name
417
(recipient->pubkey_algo));
418
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
419
fprintf_plus(stderr, "Secret key available: %s\n",
420
recipient->status == GPG_ERR_NO_SECKEY
421
? "No" : "Yes");
422
recipient = recipient->next;
423
}
424
}
425
}
426
goto decrypt_end;
427
}
428
429
if(debug){
430
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
431
}
432
433
/* Seek back to the beginning of the GPGME plaintext data buffer */
434
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
435
perror_plus("gpgme_data_seek");
436
plaintext_length = -1;
437
goto decrypt_end;
438
}
439
440
*plaintext = NULL;
441
while(true){
442
plaintext_capacity = incbuffer(plaintext,
443
(size_t)plaintext_length,
444
plaintext_capacity);
445
if(plaintext_capacity == 0){
446
perror_plus("incbuffer");
447
plaintext_length = -1;
448
goto decrypt_end;
449
}
450
451
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
452
BUFFER_SIZE);
453
/* Print the data, if any */
454
if(ret == 0){
455
/* EOF */
456
break;
457
}
458
if(ret < 0){
459
perror_plus("gpgme_data_read");
460
plaintext_length = -1;
461
goto decrypt_end;
462
}
463
plaintext_length += ret;
464
}
465
466
if(debug){
467
fprintf_plus(stderr, "Decrypted password is: ");
468
for(ssize_t i = 0; i < plaintext_length; i++){
469
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
470
}
471
fprintf(stderr, "\n");
472
}
473
474
decrypt_end:
475
476
/* Delete the GPGME cryptotext data buffer */
477
gpgme_data_release(dh_crypto);
478
479
/* Delete the GPGME plaintext data buffer */
480
gpgme_data_release(dh_plain);
481
return plaintext_length;
482
}
483
484
__attribute__((warn_unused_result))
485
static const char *safer_gnutls_strerror(int value){
486
const char *ret = gnutls_strerror(value);
487
if(ret == NULL)
488
ret = "(unknown)";
489
return ret;
490
}
491
492
/* GnuTLS log function callback */
493
__attribute__((nonnull))
494
static void debuggnutls(__attribute__((unused)) int level,
495
const char* string){
496
fprintf_plus(stderr, "GnuTLS: %s", string);
497
}
498
499
__attribute__((nonnull, warn_unused_result))
500
static int init_gnutls_global(const char *pubkeyfilename,
501
const char *seckeyfilename,
502
mandos_context *mc){
503
int ret;
504
505
if(debug){
506
fprintf_plus(stderr, "Initializing GnuTLS\n");
507
}
508
509
ret = gnutls_global_init();
510
if(ret != GNUTLS_E_SUCCESS){
511
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
512
safer_gnutls_strerror(ret));
513
return -1;
514
}
515
516
if(debug){
517
/* "Use a log level over 10 to enable all debugging options."
518
* - GnuTLS manual
519
*/
520
gnutls_global_set_log_level(11);
521
gnutls_global_set_log_function(debuggnutls);
522
}
523
524
/* OpenPGP credentials */
525
ret = gnutls_certificate_allocate_credentials(&mc->cred);
526
if(ret != GNUTLS_E_SUCCESS){
527
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
528
safer_gnutls_strerror(ret));
529
gnutls_global_deinit();
530
return -1;
531
}
532
533
if(debug){
534
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
535
" secret key %s as GnuTLS credentials\n",
536
pubkeyfilename,
537
seckeyfilename);
538
}
539
540
ret = gnutls_certificate_set_openpgp_key_file
541
(mc->cred, pubkeyfilename, seckeyfilename,
542
GNUTLS_OPENPGP_FMT_BASE64);
543
if(ret != GNUTLS_E_SUCCESS){
544
fprintf_plus(stderr,
545
"Error[%d] while reading the OpenPGP key pair ('%s',"
546
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
547
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
548
safer_gnutls_strerror(ret));
549
goto globalfail;
550
}
551
552
/* GnuTLS server initialization */
553
ret = gnutls_dh_params_init(&mc->dh_params);
554
if(ret != GNUTLS_E_SUCCESS){
555
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
556
" initialization: %s\n",
557
safer_gnutls_strerror(ret));
558
goto globalfail;
559
}
560
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
561
if(ret != GNUTLS_E_SUCCESS){
562
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
563
safer_gnutls_strerror(ret));
564
goto globalfail;
565
}
566
567
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
568
569
return 0;
570
571
globalfail:
572
573
gnutls_certificate_free_credentials(mc->cred);
574
gnutls_global_deinit();
575
gnutls_dh_params_deinit(mc->dh_params);
576
return -1;
577
}
578
579
__attribute__((nonnull, warn_unused_result))
580
static int init_gnutls_session(gnutls_session_t *session,
581
mandos_context *mc){
582
int ret;
583
/* GnuTLS session creation */
584
do {
585
ret = gnutls_init(session, GNUTLS_SERVER);
586
if(quit_now){
587
return -1;
588
}
589
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
590
if(ret != GNUTLS_E_SUCCESS){
591
fprintf_plus(stderr,
592
"Error in GnuTLS session initialization: %s\n",
593
safer_gnutls_strerror(ret));
594
}
595
596
{
597
const char *err;
598
do {
599
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
600
if(quit_now){
601
gnutls_deinit(*session);
602
return -1;
603
}
604
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
605
if(ret != GNUTLS_E_SUCCESS){
606
fprintf_plus(stderr, "Syntax error at: %s\n", err);
607
fprintf_plus(stderr, "GnuTLS error: %s\n",
608
safer_gnutls_strerror(ret));
609
gnutls_deinit(*session);
610
return -1;
611
}
612
}
613
614
do {
615
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
616
mc->cred);
617
if(quit_now){
618
gnutls_deinit(*session);
619
return -1;
620
}
621
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
622
if(ret != GNUTLS_E_SUCCESS){
623
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
624
safer_gnutls_strerror(ret));
625
gnutls_deinit(*session);
626
return -1;
627
}
628
629
/* ignore client certificate if any. */
630
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
631
632
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
633
634
return 0;
635
}
636
637
/* Avahi log function callback */
638
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
639
__attribute__((unused)) const char *txt){}
640
641
/* Called when a Mandos server is found */
642
__attribute__((nonnull, warn_unused_result))
643
static int start_mandos_communication(const char *ip, in_port_t port,
644
AvahiIfIndex if_index,
645
int af, mandos_context *mc){
646
int ret, tcp_sd = -1;
647
ssize_t sret;
648
struct sockaddr_storage to;
649
char *buffer = NULL;
650
char *decrypted_buffer = NULL;
651
size_t buffer_length = 0;
652
size_t buffer_capacity = 0;
653
size_t written;
654
int retval = -1;
655
gnutls_session_t session;
656
int pf; /* Protocol family */
657
658
errno = 0;
659
660
if(quit_now){
661
errno = EINTR;
662
return -1;
663
}
664
665
switch(af){
666
case AF_INET6:
667
pf = PF_INET6;
668
break;
669
case AF_INET:
670
pf = PF_INET;
671
break;
672
default:
673
fprintf_plus(stderr, "Bad address family: %d\n", af);
674
errno = EINVAL;
675
return -1;
676
}
677
678
/* If the interface is specified and we have a list of interfaces */
679
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
680
/* Check if the interface is one of the interfaces we are using */
681
bool match = false;
682
{
683
char *interface = NULL;
684
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
685
interface))){
686
if(if_nametoindex(interface) == (unsigned int)if_index){
687
match = true;
688
break;
689
}
690
}
691
}
692
if(not match){
693
/* This interface does not match any in the list, so we don't
694
connect to the server */
695
if(debug){
696
char interface[IF_NAMESIZE];
697
if(if_indextoname((unsigned int)if_index, interface) == NULL){
698
perror_plus("if_indextoname");
699
} else {
700
fprintf_plus(stderr, "Skipping server on non-used interface"
701
" \"%s\"\n",
702
if_indextoname((unsigned int)if_index,
703
interface));
704
}
705
}
706
return -1;
707
}
708
}
709
710
ret = init_gnutls_session(&session, mc);
711
if(ret != 0){
712
return -1;
713
}
714
715
if(debug){
716
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
717
PRIuMAX "\n", ip, (uintmax_t)port);
718
}
719
720
tcp_sd = socket(pf, SOCK_STREAM, 0);
721
if(tcp_sd < 0){
722
int e = errno;
723
perror_plus("socket");
724
errno = e;
725
goto mandos_end;
726
}
727
728
if(quit_now){
729
errno = EINTR;
730
goto mandos_end;
731
}
732
733
memset(&to, 0, sizeof(to));
734
if(af == AF_INET6){
735
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
736
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
737
} else { /* IPv4 */
738
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
739
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
740
}
741
if(ret < 0 ){
742
int e = errno;
743
perror_plus("inet_pton");
744
errno = e;
745
goto mandos_end;
746
}
747
if(ret == 0){
748
int e = errno;
749
fprintf_plus(stderr, "Bad address: %s\n", ip);
750
errno = e;
751
goto mandos_end;
752
}
753
if(af == AF_INET6){
754
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
755
if(IN6_IS_ADDR_LINKLOCAL
756
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
757
if(if_index == AVAHI_IF_UNSPEC){
758
fprintf_plus(stderr, "An IPv6 link-local address is"
759
" incomplete without a network interface\n");
760
errno = EINVAL;
761
goto mandos_end;
762
}
763
/* Set the network interface number as scope */
764
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
765
}
766
} else {
767
((struct sockaddr_in *)&to)->sin_port = htons(port);
768
}
769
770
if(quit_now){
771
errno = EINTR;
772
goto mandos_end;
773
}
774
775
if(debug){
776
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
777
char interface[IF_NAMESIZE];
778
if(if_indextoname((unsigned int)if_index, interface) == NULL){
779
perror_plus("if_indextoname");
780
} else {
781
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
782
"\n", ip, interface, (uintmax_t)port);
783
}
784
} else {
785
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
786
ip, (uintmax_t)port);
787
}
788
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
789
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
790
if(af == AF_INET6){
791
ret = getnameinfo((struct sockaddr *)&to,
792
sizeof(struct sockaddr_in6),
793
addrstr, sizeof(addrstr), NULL, 0,
794
NI_NUMERICHOST);
795
} else {
796
ret = getnameinfo((struct sockaddr *)&to,
797
sizeof(struct sockaddr_in),
798
addrstr, sizeof(addrstr), NULL, 0,
799
NI_NUMERICHOST);
800
}
801
if(ret == EAI_SYSTEM){
802
perror_plus("getnameinfo");
803
} else if(ret != 0) {
804
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
805
} else if(strcmp(addrstr, ip) != 0){
806
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
807
}
808
}
809
810
if(quit_now){
811
errno = EINTR;
812
goto mandos_end;
813
}
814
815
if(af == AF_INET6){
816
ret = connect(tcp_sd, (struct sockaddr *)&to,
817
sizeof(struct sockaddr_in6));
818
} else {
819
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
820
sizeof(struct sockaddr_in));
821
}
822
if(ret < 0){
823
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
824
int e = errno;
825
perror_plus("connect");
826
errno = e;
827
}
828
goto mandos_end;
829
}
830
831
if(quit_now){
832
errno = EINTR;
833
goto mandos_end;
834
}
835
836
const char *out = mandos_protocol_version;
837
written = 0;
838
while(true){
839
size_t out_size = strlen(out);
840
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
841
out_size - written));
842
if(ret == -1){
843
int e = errno;
844
perror_plus("write");
845
errno = e;
846
goto mandos_end;
847
}
848
written += (size_t)ret;
849
if(written < out_size){
850
continue;
851
} else {
852
if(out == mandos_protocol_version){
853
written = 0;
854
out = "\r\n";
855
} else {
856
break;
857
}
858
}
859
860
if(quit_now){
861
errno = EINTR;
862
goto mandos_end;
863
}
864
}
865
866
if(debug){
867
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
868
}
869
870
if(quit_now){
871
errno = EINTR;
872
goto mandos_end;
873
}
874
875
/* This casting via intptr_t is to eliminate warning about casting
876
an int to a pointer type. This is exactly how the GnuTLS Guile
877
function "set-session-transport-fd!" does it. */
878
gnutls_transport_set_ptr(session,
879
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
880
881
if(quit_now){
882
errno = EINTR;
883
goto mandos_end;
884
}
885
886
do {
887
ret = gnutls_handshake(session);
888
if(quit_now){
889
errno = EINTR;
890
goto mandos_end;
891
}
892
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
893
894
if(ret != GNUTLS_E_SUCCESS){
895
if(debug){
896
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
897
gnutls_perror(ret);
898
}
899
errno = EPROTO;
900
goto mandos_end;
901
}
902
903
/* Read OpenPGP packet that contains the wanted password */
904
905
if(debug){
906
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
907
" %s\n", ip);
908
}
909
910
while(true){
911
912
if(quit_now){
913
errno = EINTR;
914
goto mandos_end;
915
}
916
917
buffer_capacity = incbuffer(&buffer, buffer_length,
918
buffer_capacity);
919
if(buffer_capacity == 0){
920
int e = errno;
921
perror_plus("incbuffer");
922
errno = e;
923
goto mandos_end;
924
}
925
926
if(quit_now){
927
errno = EINTR;
928
goto mandos_end;
929
}
930
931
sret = gnutls_record_recv(session, buffer+buffer_length,
932
BUFFER_SIZE);
933
if(sret == 0){
934
break;
935
}
936
if(sret < 0){
937
switch(sret){
938
case GNUTLS_E_INTERRUPTED:
939
case GNUTLS_E_AGAIN:
940
break;
941
case GNUTLS_E_REHANDSHAKE:
942
do {
943
ret = gnutls_handshake(session);
944
945
if(quit_now){
946
errno = EINTR;
947
goto mandos_end;
948
}
949
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
950
if(ret < 0){
951
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
952
"***\n");
953
gnutls_perror(ret);
954
errno = EPROTO;
955
goto mandos_end;
956
}
957
break;
958
default:
959
fprintf_plus(stderr, "Unknown error while reading data from"
960
" encrypted session with Mandos server\n");
961
gnutls_bye(session, GNUTLS_SHUT_RDWR);
962
errno = EIO;
963
goto mandos_end;
964
}
965
} else {
966
buffer_length += (size_t) sret;
967
}
968
}
969
970
if(debug){
971
fprintf_plus(stderr, "Closing TLS session\n");
972
}
973
974
if(quit_now){
975
errno = EINTR;
976
goto mandos_end;
977
}
978
979
do {
980
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
981
if(quit_now){
982
errno = EINTR;
983
goto mandos_end;
984
}
985
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
986
987
if(buffer_length > 0){
988
ssize_t decrypted_buffer_size;
989
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
990
&decrypted_buffer, mc);
991
if(decrypted_buffer_size >= 0){
992
993
written = 0;
994
while(written < (size_t) decrypted_buffer_size){
995
if(quit_now){
996
errno = EINTR;
997
goto mandos_end;
998
}
999
1000
ret = (int)fwrite(decrypted_buffer + written, 1,
1001
(size_t)decrypted_buffer_size - written,
1002
stdout);
1003
if(ret == 0 and ferror(stdout)){
1004
int e = errno;
1005
if(debug){
1006
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1007
strerror(errno));
1008
}
1009
errno = e;
1010
goto mandos_end;
1011
}
1012
written += (size_t)ret;
1013
}
1014
retval = 0;
1015
}
1016
}
1017
1018
/* Shutdown procedure */
1019
1020
mandos_end:
1021
{
1022
int e = errno;
1023
free(decrypted_buffer);
1024
free(buffer);
1025
if(tcp_sd >= 0){
1026
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1027
}
1028
if(ret == -1){
1029
if(e == 0){
1030
e = errno;
1031
}
1032
perror_plus("close");
1033
}
1034
gnutls_deinit(session);
1035
errno = e;
1036
if(quit_now){
1037
errno = EINTR;
1038
retval = -1;
1039
}
1040
}
1041
return retval;
1042
}
1043
1044
__attribute__((nonnull))
1045
static void resolve_callback(AvahiSServiceResolver *r,
1046
AvahiIfIndex interface,
1047
AvahiProtocol proto,
1048
AvahiResolverEvent event,
1049
const char *name,
1050
const char *type,
1051
const char *domain,
1052
const char *host_name,
1053
const AvahiAddress *address,
1054
uint16_t port,
1055
AVAHI_GCC_UNUSED AvahiStringList *txt,
1056
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1057
flags,
1058
void *mc){
1059
if(r == NULL){
1060
return;
1061
}
1062
1063
/* Called whenever a service has been resolved successfully or
1064
timed out */
1065
1066
if(quit_now){
1067
return;
1068
}
1069
1070
switch(event){
1071
default:
1072
case AVAHI_RESOLVER_FAILURE:
1073
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1074
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1075
domain,
1076
avahi_strerror(avahi_server_errno
1077
(((mandos_context*)mc)->server)));
1078
break;
1079
1080
case AVAHI_RESOLVER_FOUND:
1081
{
1082
char ip[AVAHI_ADDRESS_STR_MAX];
1083
avahi_address_snprint(ip, sizeof(ip), address);
1084
if(debug){
1085
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1086
PRIdMAX ") on port %" PRIu16 "\n", name,
1087
host_name, ip, (intmax_t)interface, port);
1088
}
1089
int ret = start_mandos_communication(ip, (in_port_t)port,
1090
interface,
1091
avahi_proto_to_af(proto),
1092
mc);
1093
if(ret == 0){
1094
avahi_simple_poll_quit(simple_poll);
1095
} else {
1096
if(not add_server(ip, (in_port_t)port, interface,
1097
avahi_proto_to_af(proto),
1098
&((mandos_context*)mc)->current_server)){
1099
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1100
" list\n", name);
1101
}
1102
}
1103
}
1104
}
1105
avahi_s_service_resolver_free(r);
1106
}
1107
1108
static void browse_callback(AvahiSServiceBrowser *b,
1109
AvahiIfIndex interface,
1110
AvahiProtocol protocol,
1111
AvahiBrowserEvent event,
1112
const char *name,
1113
const char *type,
1114
const char *domain,
1115
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1116
flags,
1117
void *mc){
1118
if(b == NULL){
1119
return;
1120
}
1121
1122
/* Called whenever a new services becomes available on the LAN or
1123
is removed from the LAN */
1124
1125
if(quit_now){
1126
return;
1127
}
1128
1129
switch(event){
1130
default:
1131
case AVAHI_BROWSER_FAILURE:
1132
1133
fprintf_plus(stderr, "(Avahi browser) %s\n",
1134
avahi_strerror(avahi_server_errno
1135
(((mandos_context*)mc)->server)));
1136
avahi_simple_poll_quit(simple_poll);
1137
return;
1138
1139
case AVAHI_BROWSER_NEW:
1140
/* We ignore the returned Avahi resolver object. In the callback
1141
function we free it. If the Avahi server is terminated before
1142
the callback function is called the Avahi server will free the
1143
resolver for us. */
1144
1145
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1146
interface, protocol, name, type,
1147
domain, protocol, 0,
1148
resolve_callback, mc) == NULL)
1149
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1150
" %s\n", name,
1151
avahi_strerror(avahi_server_errno
1152
(((mandos_context*)mc)->server)));
1153
break;
1154
1155
case AVAHI_BROWSER_REMOVE:
1156
break;
1157
1158
case AVAHI_BROWSER_ALL_FOR_NOW:
1159
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1160
if(debug){
1161
fprintf_plus(stderr, "No Mandos server found, still"
1162
" searching...\n");
1163
}
1164
break;
1165
}
1166
}
1167
1168
/* Signal handler that stops main loop after SIGTERM */
1169
static void handle_sigterm(int sig){
1170
if(quit_now){
1171
return;
1172
}
1173
quit_now = 1;
1174
signal_received = sig;
1175
int old_errno = errno;
1176
/* set main loop to exit */
1177
if(simple_poll != NULL){
1178
avahi_simple_poll_quit(simple_poll);
1179
}
1180
errno = old_errno;
1181
}
1182
1183
__attribute__((nonnull, warn_unused_result))
1184
bool get_flags(const char *ifname, struct ifreq *ifr){
1185
int ret;
1186
error_t ret_errno;
1187
1188
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1189
if(s < 0){
1190
ret_errno = errno;
1191
perror_plus("socket");
1192
errno = ret_errno;
1193
return false;
1194
}
1195
strcpy(ifr->ifr_name, ifname);
1196
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1197
if(ret == -1){
1198
if(debug){
1199
ret_errno = errno;
1200
perror_plus("ioctl SIOCGIFFLAGS");
1201
errno = ret_errno;
1202
}
1203
return false;
1204
}
1205
return true;
1206
}
1207
1208
__attribute__((nonnull, warn_unused_result))
1209
bool good_flags(const char *ifname, const struct ifreq *ifr){
1210
1211
/* Reject the loopback device */
1212
if(ifr->ifr_flags & IFF_LOOPBACK){
1213
if(debug){
1214
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1215
ifname);
1216
}
1217
return false;
1218
}
1219
/* Accept point-to-point devices only if connect_to is specified */
1220
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1221
if(debug){
1222
fprintf_plus(stderr, "Accepting point-to-point interface"
1223
" \"%s\"\n", ifname);
1224
}
1225
return true;
1226
}
1227
/* Otherwise, reject non-broadcast-capable devices */
1228
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1229
if(debug){
1230
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1231
" \"%s\"\n", ifname);
1232
}
1233
return false;
1234
}
1235
/* Reject non-ARP interfaces (including dummy interfaces) */
1236
if(ifr->ifr_flags & IFF_NOARP){
1237
if(debug){
1238
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1239
ifname);
1240
}
1241
return false;
1242
}
1243
1244
/* Accept this device */
1245
if(debug){
1246
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1247
}
1248
return true;
1249
}
1250
1251
/*
1252
* This function determines if a directory entry in /sys/class/net
1253
* corresponds to an acceptable network device.
1254
* (This function is passed to scandir(3) as a filter function.)
1255
*/
1256
__attribute__((nonnull, warn_unused_result))
1257
int good_interface(const struct dirent *if_entry){
1258
if(if_entry->d_name[0] == '.'){
1259
return 0;
1260
}
1261
1262
struct ifreq ifr;
1263
if(not get_flags(if_entry->d_name, &ifr)){
1264
if(debug){
1265
fprintf_plus(stderr, "Failed to get flags for interface "
1266
"\"%s\"\n", if_entry->d_name);
1267
}
1268
return 0;
1269
}
1270
1271
if(not good_flags(if_entry->d_name, &ifr)){
1272
return 0;
1273
}
1274
return 1;
1275
}
1276
1277
/*
1278
* This function determines if a network interface is up.
1279
*/
1280
__attribute__((nonnull, warn_unused_result))
1281
bool interface_is_up(const char *interface){
1282
struct ifreq ifr;
1283
if(not get_flags(interface, &ifr)){
1284
if(debug){
1285
fprintf_plus(stderr, "Failed to get flags for interface "
1286
"\"%s\"\n", interface);
1287
}
1288
return false;
1289
}
1290
1291
return (bool)(ifr.ifr_flags & IFF_UP);
1292
}
1293
1294
/*
1295
* This function determines if a network interface is running
1296
*/
1297
__attribute__((nonnull, warn_unused_result))
1298
bool interface_is_running(const char *interface){
1299
struct ifreq ifr;
1300
if(not get_flags(interface, &ifr)){
1301
if(debug){
1302
fprintf_plus(stderr, "Failed to get flags for interface "
1303
"\"%s\"\n", interface);
1304
}
1305
return false;
1306
}
1307
1308
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1309
}
1310
1311
__attribute__((nonnull, pure, warn_unused_result))
1312
int notdotentries(const struct dirent *direntry){
1313
/* Skip "." and ".." */
1314
if(direntry->d_name[0] == '.'
1315
and (direntry->d_name[1] == '\0'
1316
or (direntry->d_name[1] == '.'
1317
and direntry->d_name[2] == '\0'))){
1318
return 0;
1319
}
1320
return 1;
1321
}
1322
1323
/* Is this directory entry a runnable program? */
1324
__attribute__((nonnull, warn_unused_result))
1325
int runnable_hook(const struct dirent *direntry){
1326
int ret;
1327
size_t sret;
1328
struct stat st;
1329
1330
if((direntry->d_name)[0] == '\0'){
1331
/* Empty name? */
1332
return 0;
1333
}
1334
1335
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1336
"abcdefghijklmnopqrstuvwxyz"
1337
"0123456789"
1338
"_.-");
1339
if((direntry->d_name)[sret] != '\0'){
1340
/* Contains non-allowed characters */
1341
if(debug){
1342
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1343
direntry->d_name);
1344
}
1345
return 0;
1346
}
1347
1348
char *fullname = NULL;
1349
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1350
if(ret < 0){
1351
perror_plus("asprintf");
1352
return 0;
1353
}
1354
1355
ret = stat(fullname, &st);
1356
if(ret == -1){
1357
if(debug){
1358
perror_plus("Could not stat hook");
1359
}
1360
return 0;
1361
}
1362
free(fullname);
1363
if(not (S_ISREG(st.st_mode))){
1364
/* Not a regular file */
1365
if(debug){
1366
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1367
direntry->d_name);
1368
}
1369
return 0;
1370
}
1371
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1372
/* Not executable */
1373
if(debug){
1374
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1375
direntry->d_name);
1376
}
1377
return 0;
1378
}
1379
if(debug){
1380
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1381
direntry->d_name);
1382
}
1383
return 1;
1384
}
1385
1386
__attribute__((nonnull, warn_unused_result))
1387
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1388
mandos_context *mc){
1389
int ret;
1390
struct timespec now;
1391
struct timespec waited_time;
1392
intmax_t block_time;
1393
1394
while(true){
1395
if(mc->current_server == NULL){
1396
if(debug){
1397
fprintf_plus(stderr, "Wait until first server is found."
1398
" No timeout!\n");
1399
}
1400
ret = avahi_simple_poll_iterate(s, -1);
1401
} else {
1402
if(debug){
1403
fprintf_plus(stderr, "Check current_server if we should run"
1404
" it, or wait\n");
1405
}
1406
/* the current time */
1407
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1408
if(ret == -1){
1409
perror_plus("clock_gettime");
1410
return -1;
1411
}
1412
/* Calculating in ms how long time between now and server
1413
who we visted longest time ago. Now - last seen. */
1414
waited_time.tv_sec = (now.tv_sec
1415
- mc->current_server->last_seen.tv_sec);
1416
waited_time.tv_nsec = (now.tv_nsec
1417
- mc->current_server->last_seen.tv_nsec);
1418
/* total time is 10s/10,000ms.
1419
Converting to s from ms by dividing by 1,000,
1420
and ns to ms by dividing by 1,000,000. */
1421
block_time = ((retry_interval
1422
- ((intmax_t)waited_time.tv_sec * 1000))
1423
- ((intmax_t)waited_time.tv_nsec / 1000000));
1424
1425
if(debug){
1426
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1427
block_time);
1428
}
1429
1430
if(block_time <= 0){
1431
ret = start_mandos_communication(mc->current_server->ip,
1432
mc->current_server->port,
1433
mc->current_server->if_index,
1434
mc->current_server->af, mc);
1435
if(ret == 0){
1436
avahi_simple_poll_quit(s);
1437
return 0;
1438
}
1439
ret = clock_gettime(CLOCK_MONOTONIC,
1440
&mc->current_server->last_seen);
1441
if(ret == -1){
1442
perror_plus("clock_gettime");
1443
return -1;
1444
}
1445
mc->current_server = mc->current_server->next;
1446
block_time = 0; /* Call avahi to find new Mandos
1447
servers, but don't block */
1448
}
1449
1450
ret = avahi_simple_poll_iterate(s, (int)block_time);
1451
}
1452
if(ret != 0){
1453
if(ret > 0 or errno != EINTR){
1454
return (ret != 1) ? ret : 0;
1455
}
1456
}
1457
}
1458
}
1459
1460
/* Set effective uid to 0, return errno */
1461
__attribute__((warn_unused_result))
1462
error_t raise_privileges(void){
1463
error_t old_errno = errno;
1464
error_t ret_errno = 0;
1465
if(seteuid(0) == -1){
1466
ret_errno = errno;
1467
perror_plus("seteuid");
1468
}
1469
errno = old_errno;
1470
return ret_errno;
1471
}
1472
1473
/* Set effective and real user ID to 0. Return errno. */
1474
__attribute__((warn_unused_result))
1475
error_t raise_privileges_permanently(void){
1476
error_t old_errno = errno;
1477
error_t ret_errno = raise_privileges();
1478
if(ret_errno != 0){
1479
errno = old_errno;
1480
return ret_errno;
1481
}
1482
if(setuid(0) == -1){
1483
ret_errno = errno;
1484
perror_plus("seteuid");
1485
}
1486
errno = old_errno;
1487
return ret_errno;
1488
}
1489
1490
/* Set effective user ID to unprivileged saved user ID */
1491
__attribute__((warn_unused_result))
1492
error_t lower_privileges(void){
1493
error_t old_errno = errno;
1494
error_t ret_errno = 0;
1495
if(seteuid(uid) == -1){
1496
ret_errno = errno;
1497
perror_plus("seteuid");
1498
}
1499
errno = old_errno;
1500
return ret_errno;
1501
}
1502
1503
/* Lower privileges permanently */
1504
__attribute__((warn_unused_result))
1505
error_t lower_privileges_permanently(void){
1506
error_t old_errno = errno;
1507
error_t ret_errno = 0;
1508
if(setuid(uid) == -1){
1509
ret_errno = errno;
1510
perror_plus("setuid");
1511
}
1512
errno = old_errno;
1513
return ret_errno;
1514
}
1515
1516
__attribute__((nonnull))
1517
void run_network_hooks(const char *mode, const char *interface,
1518
const float delay){
1519
struct dirent **direntries;
1520
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1521
alphasort);
1522
if(numhooks == -1){
1523
if(errno == ENOENT){
1524
if(debug){
1525
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1526
" found\n", hookdir);
1527
}
1528
} else {
1529
perror_plus("scandir");
1530
}
1531
} else {
1532
struct dirent *direntry;
1533
int ret;
1534
int devnull = open("/dev/null", O_RDONLY);
1535
for(int i = 0; i < numhooks; i++){
1536
direntry = direntries[i];
1537
char *fullname = NULL;
1538
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1539
if(ret < 0){
1540
perror_plus("asprintf");
1541
continue;
1542
}
1543
if(debug){
1544
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1545
direntry->d_name);
1546
}
1547
pid_t hook_pid = fork();
1548
if(hook_pid == 0){
1549
/* Child */
1550
/* Raise privileges */
1551
if(raise_privileges_permanently() != 0){
1552
perror_plus("Failed to raise privileges");
1553
_exit(EX_NOPERM);
1554
}
1555
/* Set group */
1556
errno = 0;
1557
ret = setgid(0);
1558
if(ret == -1){
1559
perror_plus("setgid");
1560
_exit(EX_NOPERM);
1561
}
1562
/* Reset supplementary groups */
1563
errno = 0;
1564
ret = setgroups(0, NULL);
1565
if(ret == -1){
1566
perror_plus("setgroups");
1567
_exit(EX_NOPERM);
1568
}
1569
ret = dup2(devnull, STDIN_FILENO);
1570
if(ret == -1){
1571
perror_plus("dup2(devnull, STDIN_FILENO)");
1572
_exit(EX_OSERR);
1573
}
1574
ret = close(devnull);
1575
if(ret == -1){
1576
perror_plus("close");
1577
_exit(EX_OSERR);
1578
}
1579
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1580
if(ret == -1){
1581
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1582
_exit(EX_OSERR);
1583
}
1584
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1585
if(ret == -1){
1586
perror_plus("setenv");
1587
_exit(EX_OSERR);
1588
}
1589
ret = setenv("DEVICE", interface, 1);
1590
if(ret == -1){
1591
perror_plus("setenv");
1592
_exit(EX_OSERR);
1593
}
1594
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1595
if(ret == -1){
1596
perror_plus("setenv");
1597
_exit(EX_OSERR);
1598
}
1599
ret = setenv("MODE", mode, 1);
1600
if(ret == -1){
1601
perror_plus("setenv");
1602
_exit(EX_OSERR);
1603
}
1604
char *delaystring;
1605
ret = asprintf(&delaystring, "%f", (double)delay);
1606
if(ret == -1){
1607
perror_plus("asprintf");
1608
_exit(EX_OSERR);
1609
}
1610
ret = setenv("DELAY", delaystring, 1);
1611
if(ret == -1){
1612
free(delaystring);
1613
perror_plus("setenv");
1614
_exit(EX_OSERR);
1615
}
1616
free(delaystring);
1617
if(connect_to != NULL){
1618
ret = setenv("CONNECT", connect_to, 1);
1619
if(ret == -1){
1620
perror_plus("setenv");
1621
_exit(EX_OSERR);
1622
}
1623
}
1624
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1625
perror_plus("execl");
1626
_exit(EXIT_FAILURE);
1627
}
1628
} else {
1629
int status;
1630
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1631
perror_plus("waitpid");
1632
free(fullname);
1633
continue;
1634
}
1635
if(WIFEXITED(status)){
1636
if(WEXITSTATUS(status) != 0){
1637
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1638
" with status %d\n", direntry->d_name,
1639
WEXITSTATUS(status));
1640
free(fullname);
1641
continue;
1642
}
1643
} else if(WIFSIGNALED(status)){
1644
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1645
" signal %d\n", direntry->d_name,
1646
WTERMSIG(status));
1647
free(fullname);
1648
continue;
1649
} else {
1650
fprintf_plus(stderr, "Warning: network hook \"%s\""
1651
" crashed\n", direntry->d_name);
1652
free(fullname);
1653
continue;
1654
}
1655
}
1656
free(fullname);
1657
if(debug){
1658
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1659
direntry->d_name);
1660
}
1661
}
1662
close(devnull);
1663
}
1664
}
1665
1666
__attribute__((nonnull, warn_unused_result))
1667
error_t bring_up_interface(const char *const interface,
1668
const float delay){
1669
error_t old_errno = errno;
1670
int ret;
1671
struct ifreq network;
1672
unsigned int if_index = if_nametoindex(interface);
1673
if(if_index == 0){
1674
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1675
errno = old_errno;
1676
return ENXIO;
1677
}
1678
1679
if(quit_now){
1680
errno = old_errno;
1681
return EINTR;
1682
}
1683
1684
if(not interface_is_up(interface)){
1685
error_t ret_errno = 0, ioctl_errno = 0;
1686
if(not get_flags(interface, &network)){
1687
ret_errno = errno;
1688
fprintf_plus(stderr, "Failed to get flags for interface "
1689
"\"%s\"\n", interface);
1690
errno = old_errno;
1691
return ret_errno;
1692
}
1693
network.ifr_flags |= IFF_UP; /* set flag */
1694
1695
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1696
if(sd == -1){
1697
ret_errno = errno;
1698
perror_plus("socket");
1699
errno = old_errno;
1700
return ret_errno;
1701
}
1702
1703
if(quit_now){
1704
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1705
if(ret == -1){
1706
perror_plus("close");
1707
}
1708
errno = old_errno;
1709
return EINTR;
1710
}
1711
1712
if(debug){
1713
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1714
interface);
1715
}
1716
1717
/* Raise privileges */
1718
ret_errno = raise_privileges();
1719
if(ret_errno != 0){
1720
perror_plus("Failed to raise privileges");
1721
}
1722
1723
#ifdef __linux__
1724
int ret_linux;
1725
bool restore_loglevel = false;
1726
if(ret_errno == 0){
1727
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1728
messages about the network interface to mess up the prompt */
1729
ret_linux = klogctl(8, NULL, 5);
1730
if(ret_linux == -1){
1731
perror_plus("klogctl");
1732
} else {
1733
restore_loglevel = true;
1734
}
1735
}
1736
#endif /* __linux__ */
1737
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1738
ioctl_errno = errno;
1739
#ifdef __linux__
1740
if(restore_loglevel){
1741
ret_linux = klogctl(7, NULL, 0);
1742
if(ret_linux == -1){
1743
perror_plus("klogctl");
1744
}
1745
}
1746
#endif /* __linux__ */
1747
1748
/* If raise_privileges() succeeded above */
1749
if(ret_errno == 0){
1750
/* Lower privileges */
1751
ret_errno = lower_privileges();
1752
if(ret_errno != 0){
1753
errno = ret_errno;
1754
perror_plus("Failed to lower privileges");
1755
}
1756
}
1757
1758
/* Close the socket */
1759
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1760
if(ret == -1){
1761
perror_plus("close");
1762
}
1763
1764
if(ret_setflags == -1){
1765
errno = ioctl_errno;
1766
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1767
errno = old_errno;
1768
return ioctl_errno;
1769
}
1770
} else if(debug){
1771
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1772
interface);
1773
}
1774
1775
/* Sleep checking until interface is running.
1776
Check every 0.25s, up to total time of delay */
1777
for(int i=0; i < delay * 4; i++){
1778
if(interface_is_running(interface)){
1779
break;
1780
}
1781
struct timespec sleeptime = { .tv_nsec = 250000000 };
1782
ret = nanosleep(&sleeptime, NULL);
1783
if(ret == -1 and errno != EINTR){
1784
perror_plus("nanosleep");
1785
}
1786
}
1787
1788
errno = old_errno;
1789
return 0;
1790
}
1791
1792
__attribute__((nonnull, warn_unused_result))
1793
error_t take_down_interface(const char *const interface){
1794
error_t old_errno = errno;
1795
struct ifreq network;
1796
unsigned int if_index = if_nametoindex(interface);
1797
if(if_index == 0){
1798
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1799
errno = old_errno;
1800
return ENXIO;
1801
}
1802
if(interface_is_up(interface)){
1803
error_t ret_errno = 0, ioctl_errno = 0;
1804
if(not get_flags(interface, &network) and debug){
1805
ret_errno = errno;
1806
fprintf_plus(stderr, "Failed to get flags for interface "
1807
"\"%s\"\n", interface);
1808
errno = old_errno;
1809
return ret_errno;
1810
}
1811
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1812
1813
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1814
if(sd == -1){
1815
ret_errno = errno;
1816
perror_plus("socket");
1817
errno = old_errno;
1818
return ret_errno;
1819
}
1820
1821
if(debug){
1822
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1823
interface);
1824
}
1825
1826
/* Raise privileges */
1827
ret_errno = raise_privileges();
1828
if(ret_errno != 0){
1829
perror_plus("Failed to raise privileges");
1830
}
1831
1832
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1833
ioctl_errno = errno;
1834
1835
/* If raise_privileges() succeeded above */
1836
if(ret_errno == 0){
1837
/* Lower privileges */
1838
ret_errno = lower_privileges();
1839
if(ret_errno != 0){
1840
errno = ret_errno;
1841
perror_plus("Failed to lower privileges");
1842
}
1843
}
1844
1845
/* Close the socket */
1846
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1847
if(ret == -1){
1848
perror_plus("close");
1849
}
1850
1851
if(ret_setflags == -1){
1852
errno = ioctl_errno;
1853
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1854
errno = old_errno;
1855
return ioctl_errno;
1856
}
1857
} else if(debug){
1858
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1859
interface);
1860
}
1861
1862
errno = old_errno;
1863
return 0;
1864
}
1865
1866
int main(int argc, char *argv[]){
1867
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1868
.priority = "SECURE256:!CTYPE-X.509:"
1869
"+CTYPE-OPENPGP", .current_server = NULL,
1870
.interfaces = NULL, .interfaces_size = 0 };
1871
AvahiSServiceBrowser *sb = NULL;
1872
error_t ret_errno;
1873
int ret;
1874
intmax_t tmpmax;
1875
char *tmp;
1876
int exitcode = EXIT_SUCCESS;
1877
char *interfaces_to_take_down = NULL;
1878
size_t interfaces_to_take_down_size = 0;
1879
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1880
char old_tempdir[] = "/tmp/mandosXXXXXX";
1881
char *tempdir = NULL;
1882
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1883
const char *seckey = PATHDIR "/" SECKEY;
1884
const char *pubkey = PATHDIR "/" PUBKEY;
1885
char *interfaces_hooks = NULL;
1886
1887
bool gnutls_initialized = false;
1888
bool gpgme_initialized = false;
1889
float delay = 2.5f;
1890
double retry_interval = 10; /* 10s between trying a server and
1891
retrying the same server again */
1892
1893
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1894
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1895
1896
uid = getuid();
1897
gid = getgid();
1898
1899
/* Lower any group privileges we might have, just to be safe */
1900
errno = 0;
1901
ret = setgid(gid);
1902
if(ret == -1){
1903
perror_plus("setgid");
1904
}
1905
1906
/* Lower user privileges (temporarily) */
1907
errno = 0;
1908
ret = seteuid(uid);
1909
if(ret == -1){
1910
perror_plus("seteuid");
1911
}
1912
1913
if(quit_now){
1914
goto end;
1915
}
1916
1917
{
1918
struct argp_option options[] = {
1919
{ .name = "debug", .key = 128,
1920
.doc = "Debug mode", .group = 3 },
1921
{ .name = "connect", .key = 'c',
1922
.arg = "ADDRESS:PORT",
1923
.doc = "Connect directly to a specific Mandos server",
1924
.group = 1 },
1925
{ .name = "interface", .key = 'i',
1926
.arg = "NAME",
1927
.doc = "Network interface that will be used to search for"
1928
" Mandos servers",
1929
.group = 1 },
1930
{ .name = "seckey", .key = 's',
1931
.arg = "FILE",
1932
.doc = "OpenPGP secret key file base name",
1933
.group = 1 },
1934
{ .name = "pubkey", .key = 'p',
1935
.arg = "FILE",
1936
.doc = "OpenPGP public key file base name",
1937
.group = 2 },
1938
{ .name = "dh-bits", .key = 129,
1939
.arg = "BITS",
1940
.doc = "Bit length of the prime number used in the"
1941
" Diffie-Hellman key exchange",
1942
.group = 2 },
1943
{ .name = "priority", .key = 130,
1944
.arg = "STRING",
1945
.doc = "GnuTLS priority string for the TLS handshake",
1946
.group = 1 },
1947
{ .name = "delay", .key = 131,
1948
.arg = "SECONDS",
1949
.doc = "Maximum delay to wait for interface startup",
1950
.group = 2 },
1951
{ .name = "retry", .key = 132,
1952
.arg = "SECONDS",
1953
.doc = "Retry interval used when denied by the Mandos server",
1954
.group = 2 },
1955
{ .name = "network-hook-dir", .key = 133,
1956
.arg = "DIR",
1957
.doc = "Directory where network hooks are located",
1958
.group = 2 },
1959
/*
1960
* These reproduce what we would get without ARGP_NO_HELP
1961
*/
1962
{ .name = "help", .key = '?',
1963
.doc = "Give this help list", .group = -1 },
1964
{ .name = "usage", .key = -3,
1965
.doc = "Give a short usage message", .group = -1 },
1966
{ .name = "version", .key = 'V',
1967
.doc = "Print program version", .group = -1 },
1968
{ .name = NULL }
1969
};
1970
1971
error_t parse_opt(int key, char *arg,
1972
struct argp_state *state){
1973
errno = 0;
1974
switch(key){
1975
case 128: /* --debug */
1976
debug = true;
1977
break;
1978
case 'c': /* --connect */
1979
connect_to = arg;
1980
break;
1981
case 'i': /* --interface */
1982
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1983
arg, (int)',');
1984
if(ret_errno != 0){
1985
argp_error(state, "%s", strerror(ret_errno));
1986
}
1987
break;
1988
case 's': /* --seckey */
1989
seckey = arg;
1990
break;
1991
case 'p': /* --pubkey */
1992
pubkey = arg;
1993
break;
1994
case 129: /* --dh-bits */
1995
errno = 0;
1996
tmpmax = strtoimax(arg, &tmp, 10);
1997
if(errno != 0 or tmp == arg or *tmp != '\0'
1998
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1999
argp_error(state, "Bad number of DH bits");
2000
}
2001
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2002
break;
2003
case 130: /* --priority */
2004
mc.priority = arg;
2005
break;
2006
case 131: /* --delay */
2007
errno = 0;
2008
delay = strtof(arg, &tmp);
2009
if(errno != 0 or tmp == arg or *tmp != '\0'){
2010
argp_error(state, "Bad delay");
2011
}
2012
case 132: /* --retry */
2013
errno = 0;
2014
retry_interval = strtod(arg, &tmp);
2015
if(errno != 0 or tmp == arg or *tmp != '\0'
2016
or (retry_interval * 1000) > INT_MAX
2017
or retry_interval < 0){
2018
argp_error(state, "Bad retry interval");
2019
}
2020
break;
2021
case 133: /* --network-hook-dir */
2022
hookdir = arg;
2023
break;
2024
/*
2025
* These reproduce what we would get without ARGP_NO_HELP
2026
*/
2027
case '?': /* --help */
2028
argp_state_help(state, state->out_stream,
2029
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2030
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2031
case -3: /* --usage */
2032
argp_state_help(state, state->out_stream,
2033
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2034
case 'V': /* --version */
2035
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2036
exit(argp_err_exit_status);
2037
break;
2038
default:
2039
return ARGP_ERR_UNKNOWN;
2040
}
2041
return errno;
2042
}
2043
2044
struct argp argp = { .options = options, .parser = parse_opt,
2045
.args_doc = "",
2046
.doc = "Mandos client -- Get and decrypt"
2047
" passwords from a Mandos server" };
2048
ret = argp_parse(&argp, argc, argv,
2049
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2050
switch(ret){
2051
case 0:
2052
break;
2053
case ENOMEM:
2054
default:
2055
errno = ret;
2056
perror_plus("argp_parse");
2057
exitcode = EX_OSERR;
2058
goto end;
2059
case EINVAL:
2060
exitcode = EX_USAGE;
2061
goto end;
2062
}
2063
}
2064
2065
{
2066
/* Work around Debian bug #633582:
2067
<http://bugs.debian.org/633582> */
2068
2069
/* Re-raise privileges */
2070
ret_errno = raise_privileges();
2071
if(ret_errno != 0){
2072
errno = ret_errno;
2073
perror_plus("Failed to raise privileges");
2074
} else {
2075
struct stat st;
2076
2077
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2078
int seckey_fd = open(seckey, O_RDONLY);
2079
if(seckey_fd == -1){
2080
perror_plus("open");
2081
} else {
2082
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2083
if(ret == -1){
2084
perror_plus("fstat");
2085
} else {
2086
if(S_ISREG(st.st_mode)
2087
and st.st_uid == 0 and st.st_gid == 0){
2088
ret = fchown(seckey_fd, uid, gid);
2089
if(ret == -1){
2090
perror_plus("fchown");
2091
}
2092
}
2093
}
2094
TEMP_FAILURE_RETRY(close(seckey_fd));
2095
}
2096
}
2097
2098
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2099
int pubkey_fd = open(pubkey, O_RDONLY);
2100
if(pubkey_fd == -1){
2101
perror_plus("open");
2102
} else {
2103
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2104
if(ret == -1){
2105
perror_plus("fstat");
2106
} else {
2107
if(S_ISREG(st.st_mode)
2108
and st.st_uid == 0 and st.st_gid == 0){
2109
ret = fchown(pubkey_fd, uid, gid);
2110
if(ret == -1){
2111
perror_plus("fchown");
2112
}
2113
}
2114
}
2115
TEMP_FAILURE_RETRY(close(pubkey_fd));
2116
}
2117
}
2118
2119
/* Lower privileges */
2120
ret_errno = lower_privileges();
2121
if(ret_errno != 0){
2122
errno = ret_errno;
2123
perror_plus("Failed to lower privileges");
2124
}
2125
}
2126
}
2127
2128
/* Remove invalid interface names (except "none") */
2129
{
2130
char *interface = NULL;
2131
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2132
interface))){
2133
if(strcmp(interface, "none") != 0
2134
and if_nametoindex(interface) == 0){
2135
if(interface[0] != '\0'){
2136
fprintf_plus(stderr, "Not using nonexisting interface"
2137
" \"%s\"\n", interface);
2138
}
2139
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2140
interface = NULL;
2141
}
2142
}
2143
}
2144
2145
/* Run network hooks */
2146
{
2147
if(mc.interfaces != NULL){
2148
interfaces_hooks = malloc(mc.interfaces_size);
2149
if(interfaces_hooks == NULL){
2150
perror_plus("malloc");
2151
goto end;
2152
}
2153
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2154
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2155
}
2156
run_network_hooks("start", interfaces_hooks != NULL ?
2157
interfaces_hooks : "", delay);
2158
}
2159
2160
if(not debug){
2161
avahi_set_log_function(empty_log);
2162
}
2163
2164
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2165
from the signal handler */
2166
/* Initialize the pseudo-RNG for Avahi */
2167
srand((unsigned int) time(NULL));
2168
simple_poll = avahi_simple_poll_new();
2169
if(simple_poll == NULL){
2170
fprintf_plus(stderr,
2171
"Avahi: Failed to create simple poll object.\n");
2172
exitcode = EX_UNAVAILABLE;
2173
goto end;
2174
}
2175
2176
sigemptyset(&sigterm_action.sa_mask);
2177
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2178
if(ret == -1){
2179
perror_plus("sigaddset");
2180
exitcode = EX_OSERR;
2181
goto end;
2182
}
2183
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2184
if(ret == -1){
2185
perror_plus("sigaddset");
2186
exitcode = EX_OSERR;
2187
goto end;
2188
}
2189
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2190
if(ret == -1){
2191
perror_plus("sigaddset");
2192
exitcode = EX_OSERR;
2193
goto end;
2194
}
2195
/* Need to check if the handler is SIG_IGN before handling:
2196
| [[info:libc:Initial Signal Actions]] |
2197
| [[info:libc:Basic Signal Handling]] |
2198
*/
2199
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2200
if(ret == -1){
2201
perror_plus("sigaction");
2202
return EX_OSERR;
2203
}
2204
if(old_sigterm_action.sa_handler != SIG_IGN){
2205
ret = sigaction(SIGINT, &sigterm_action, NULL);
2206
if(ret == -1){
2207
perror_plus("sigaction");
2208
exitcode = EX_OSERR;
2209
goto end;
2210
}
2211
}
2212
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2213
if(ret == -1){
2214
perror_plus("sigaction");
2215
return EX_OSERR;
2216
}
2217
if(old_sigterm_action.sa_handler != SIG_IGN){
2218
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2219
if(ret == -1){
2220
perror_plus("sigaction");
2221
exitcode = EX_OSERR;
2222
goto end;
2223
}
2224
}
2225
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2226
if(ret == -1){
2227
perror_plus("sigaction");
2228
return EX_OSERR;
2229
}
2230
if(old_sigterm_action.sa_handler != SIG_IGN){
2231
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2232
if(ret == -1){
2233
perror_plus("sigaction");
2234
exitcode = EX_OSERR;
2235
goto end;
2236
}
2237
}
2238
2239
/* If no interfaces were specified, make a list */
2240
if(mc.interfaces == NULL){
2241
struct dirent **direntries;
2242
/* Look for any good interfaces */
2243
ret = scandir(sys_class_net, &direntries, good_interface,
2244
alphasort);
2245
if(ret >= 1){
2246
/* Add all found interfaces to interfaces list */
2247
for(int i = 0; i < ret; ++i){
2248
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2249
direntries[i]->d_name);
2250
if(ret_errno != 0){
2251
errno = ret_errno;
2252
perror_plus("argz_add");
2253
continue;
2254
}
2255
if(debug){
2256
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2257
direntries[i]->d_name);
2258
}
2259
}
2260
free(direntries);
2261
} else {
2262
free(direntries);
2263
fprintf_plus(stderr, "Could not find a network interface\n");
2264
exitcode = EXIT_FAILURE;
2265
goto end;
2266
}
2267
}
2268
2269
/* Bring up interfaces which are down, and remove any "none"s */
2270
{
2271
char *interface = NULL;
2272
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2273
interface))){
2274
/* If interface name is "none", stop bringing up interfaces.
2275
Also remove all instances of "none" from the list */
2276
if(strcmp(interface, "none") == 0){
2277
argz_delete(&mc.interfaces, &mc.interfaces_size,
2278
interface);
2279
interface = NULL;
2280
while((interface = argz_next(mc.interfaces,
2281
mc.interfaces_size, interface))){
2282
if(strcmp(interface, "none") == 0){
2283
argz_delete(&mc.interfaces, &mc.interfaces_size,
2284
interface);
2285
interface = NULL;
2286
}
2287
}
2288
break;
2289
}
2290
bool interface_was_up = interface_is_up(interface);
2291
errno = bring_up_interface(interface, delay);
2292
if(not interface_was_up){
2293
if(errno != 0){
2294
perror_plus("Failed to bring up interface");
2295
} else {
2296
errno = argz_add(&interfaces_to_take_down,
2297
&interfaces_to_take_down_size,
2298
interface);
2299
if(errno != 0){
2300
perror_plus("argz_add");
2301
}
2302
}
2303
}
2304
}
2305
if(debug and (interfaces_to_take_down == NULL)){
2306
fprintf_plus(stderr, "No interfaces were brought up\n");
2307
}
2308
}
2309
2310
/* If we only got one interface, explicitly use only that one */
2311
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2312
if(debug){
2313
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2314
mc.interfaces);
2315
}
2316
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2317
}
2318
2319
if(quit_now){
2320
goto end;
2321
}
2322
2323
ret = init_gnutls_global(pubkey, seckey, &mc);
2324
if(ret == -1){
2325
fprintf_plus(stderr, "init_gnutls_global failed\n");
2326
exitcode = EX_UNAVAILABLE;
2327
goto end;
2328
} else {
2329
gnutls_initialized = true;
2330
}
2331
2332
if(quit_now){
2333
goto end;
2334
}
2335
2336
/* Try /run/tmp before /tmp */
2337
tempdir = mkdtemp(run_tempdir);
2338
if(tempdir == NULL and errno == ENOENT){
2339
if(debug){
2340
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2341
run_tempdir, old_tempdir);
2342
}
2343
tempdir = mkdtemp(old_tempdir);
2344
}
2345
if(tempdir == NULL){
2346
perror_plus("mkdtemp");
2347
goto end;
2348
}
2349
2350
if(quit_now){
2351
goto end;
2352
}
2353
2354
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2355
fprintf_plus(stderr, "init_gpgme failed\n");
2356
exitcode = EX_UNAVAILABLE;
2357
goto end;
2358
} else {
2359
gpgme_initialized = true;
2360
}
2361
2362
if(quit_now){
2363
goto end;
2364
}
2365
2366
if(connect_to != NULL){
2367
/* Connect directly, do not use Zeroconf */
2368
/* (Mainly meant for debugging) */
2369
char *address = strrchr(connect_to, ':');
2370
2371
if(address == NULL){
2372
fprintf_plus(stderr, "No colon in address\n");
2373
exitcode = EX_USAGE;
2374
goto end;
2375
}
2376
2377
if(quit_now){
2378
goto end;
2379
}
2380
2381
in_port_t port;
2382
errno = 0;
2383
tmpmax = strtoimax(address+1, &tmp, 10);
2384
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2385
or tmpmax != (in_port_t)tmpmax){
2386
fprintf_plus(stderr, "Bad port number\n");
2387
exitcode = EX_USAGE;
2388
goto end;
2389
}
2390
2391
if(quit_now){
2392
goto end;
2393
}
2394
2395
port = (in_port_t)tmpmax;
2396
*address = '\0';
2397
/* Colon in address indicates IPv6 */
2398
int af;
2399
if(strchr(connect_to, ':') != NULL){
2400
af = AF_INET6;
2401
/* Accept [] around IPv6 address - see RFC 5952 */
2402
if(connect_to[0] == '[' and address[-1] == ']')
2403
{
2404
connect_to++;
2405
address[-1] = '\0';
2406
}
2407
} else {
2408
af = AF_INET;
2409
}
2410
address = connect_to;
2411
2412
if(quit_now){
2413
goto end;
2414
}
2415
2416
while(not quit_now){
2417
ret = start_mandos_communication(address, port, if_index, af,
2418
&mc);
2419
if(quit_now or ret == 0){
2420
break;
2421
}
2422
if(debug){
2423
fprintf_plus(stderr, "Retrying in %d seconds\n",
2424
(int)retry_interval);
2425
}
2426
sleep((unsigned int)retry_interval);
2427
}
2428
2429
if(not quit_now){
2430
exitcode = EXIT_SUCCESS;
2431
}
2432
2433
goto end;
2434
}
2435
2436
if(quit_now){
2437
goto end;
2438
}
2439
2440
{
2441
AvahiServerConfig config;
2442
/* Do not publish any local Zeroconf records */
2443
avahi_server_config_init(&config);
2444
config.publish_hinfo = 0;
2445
config.publish_addresses = 0;
2446
config.publish_workstation = 0;
2447
config.publish_domain = 0;
2448
2449
/* Allocate a new server */
2450
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2451
&config, NULL, NULL, &ret_errno);
2452
2453
/* Free the Avahi configuration data */
2454
avahi_server_config_free(&config);
2455
}
2456
2457
/* Check if creating the Avahi server object succeeded */
2458
if(mc.server == NULL){
2459
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2460
avahi_strerror(ret_errno));
2461
exitcode = EX_UNAVAILABLE;
2462
goto end;
2463
}
2464
2465
if(quit_now){
2466
goto end;
2467
}
2468
2469
/* Create the Avahi service browser */
2470
sb = avahi_s_service_browser_new(mc.server, if_index,
2471
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2472
NULL, 0, browse_callback,
2473
(void *)&mc);
2474
if(sb == NULL){
2475
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2476
avahi_strerror(avahi_server_errno(mc.server)));
2477
exitcode = EX_UNAVAILABLE;
2478
goto end;
2479
}
2480
2481
if(quit_now){
2482
goto end;
2483
}
2484
2485
/* Run the main loop */
2486
2487
if(debug){
2488
fprintf_plus(stderr, "Starting Avahi loop search\n");
2489
}
2490
2491
ret = avahi_loop_with_timeout(simple_poll,
2492
(int)(retry_interval * 1000), &mc);
2493
if(debug){
2494
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2495
(ret == 0) ? "successfully" : "with error");
2496
}
2497
2498
end:
2499
2500
if(debug){
2501
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2502
}
2503
2504
/* Cleanup things */
2505
free(mc.interfaces);
2506
2507
if(sb != NULL)
2508
avahi_s_service_browser_free(sb);
2509
2510
if(mc.server != NULL)
2511
avahi_server_free(mc.server);
2512
2513
if(simple_poll != NULL)
2514
avahi_simple_poll_free(simple_poll);
2515
2516
if(gnutls_initialized){
2517
gnutls_certificate_free_credentials(mc.cred);
2518
gnutls_global_deinit();
2519
gnutls_dh_params_deinit(mc.dh_params);
2520
}
2521
2522
if(gpgme_initialized){
2523
gpgme_release(mc.ctx);
2524
}
2525
2526
/* Cleans up the circular linked list of Mandos servers the client
2527
has seen */
2528
if(mc.current_server != NULL){
2529
mc.current_server->prev->next = NULL;
2530
while(mc.current_server != NULL){
2531
server *next = mc.current_server->next;
2532
free(mc.current_server);
2533
mc.current_server = next;
2534
}
2535
}
2536
2537
/* Re-raise privileges */
2538
{
2539
ret_errno = raise_privileges();
2540
if(ret_errno != 0){
2541
perror_plus("Failed to raise privileges");
2542
} else {
2543
2544
/* Run network hooks */
2545
run_network_hooks("stop", interfaces_hooks != NULL ?
2546
interfaces_hooks : "", delay);
2547
2548
/* Take down the network interfaces which were brought up */
2549
{
2550
char *interface = NULL;
2551
while((interface=argz_next(interfaces_to_take_down,
2552
interfaces_to_take_down_size,
2553
interface))){
2554
ret_errno = take_down_interface(interface);
2555
if(ret_errno != 0){
2556
errno = ret_errno;
2557
perror_plus("Failed to take down interface");
2558
}
2559
}
2560
if(debug and (interfaces_to_take_down == NULL)){
2561
fprintf_plus(stderr, "No interfaces needed to be taken"
2562
" down\n");
2563
}
2564
}
2565
}
2566
2567
ret_errno = lower_privileges_permanently();
2568
if(ret_errno != 0){
2569
perror_plus("Failed to lower privileges permanently");
2570
}
2571
}
2572
2573
free(interfaces_to_take_down);
2574
free(interfaces_hooks);
2575
2576
/* Removes the GPGME temp directory and all files inside */
2577
if(tempdir != NULL){
2578
struct dirent **direntries = NULL;
2579
struct dirent *direntry = NULL;
2580
int numentries = scandir(tempdir, &direntries, notdotentries,
2581
alphasort);
2582
if(numentries > 0){
2583
for(int i = 0; i < numentries; i++){
2584
direntry = direntries[i];
2585
char *fullname = NULL;
2586
ret = asprintf(&fullname, "%s/%s", tempdir,
2587
direntry->d_name);
2588
if(ret < 0){
2589
perror_plus("asprintf");
2590
continue;
2591
}
2592
ret = remove(fullname);
2593
if(ret == -1){
2594
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2595
strerror(errno));
2596
}
2597
free(fullname);
2598
}
2599
}
2600
2601
/* need to clean even if 0 because man page doesn't specify */
2602
free(direntries);
2603
if(numentries == -1){
2604
perror_plus("scandir");
2605
}
2606
ret = rmdir(tempdir);
2607
if(ret == -1 and errno != ENOENT){
2608
perror_plus("rmdir");
2609
}
2610
}
2611
2612
if(quit_now){
2613
sigemptyset(&old_sigterm_action.sa_mask);
2614
old_sigterm_action.sa_handler = SIG_DFL;
2615
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2616
&old_sigterm_action,
2617
NULL));
2618
if(ret == -1){
2619
perror_plus("sigaction");
2620
}
2621
do {
2622
ret = raise(signal_received);
2623
} while(ret != 0 and errno == EINTR);
2624
if(ret != 0){
2625
perror_plus("raise");
2626
abort();
2627
}
2628
TEMP_FAILURE_RETRY(pause());
2629
}
2630
2631
return exitcode;
2632
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0