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- Committer: Björn Påhlsson
- Date: 2007-10-28 17:59:38 UTC
- Revision ID: belorn@tower-20071028175938-26b85eaa85b84771
Working client and server and password system
- files added:
- bad-ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- network-hooks.d
- plugins.d
- 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 © 2008-2013 Teddy Hogeborn
13
* Copyright © 2008-2013 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
#include <fcntl.h> /* open() */
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
*/
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
strtoimax() */
64
#include <errno.h> /* perror(), errno,
65
program_invocation_short_name */
66
#include <time.h> /* nanosleep(), time(), sleep() */
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
SIOCSIFFLAGS, if_indextoname(),
69
if_nametoindex(), IF_NAMESIZE */
70
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
72
*/
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), seteuid(),
75
setgid(), pause(), _exit() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
77
#include <iso646.h> /* not, or, and */
78
#include <argp.h> /* struct argp_option, error_t, struct
79
argp_state, struct argp,
80
argp_parse(), ARGP_KEY_ARG,
81
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
sigaction(), SIGTERM, sig_atomic_t,
84
raise() */
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
87
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
88
WEXITSTATUS(), WTERMSIG() */
89
#include <grp.h> /* setgroups() */
90
#include <argz.h> /* argz_add_sep(), argz_next(),
91
argz_delete(), argz_append(),
92
argz_stringify(), argz_add(),
93
argz_count() */
94
95
#ifdef __linux__
96
#include <sys/klog.h> /* klogctl() */
97
#endif /* __linux__ */
98
99
/* Avahi */
100
/* All Avahi types, constants and functions
101
Avahi*, avahi_*,
102
AVAHI_* */
103
#include <avahi-core/core.h>
104
#include <avahi-core/lookup.h>
105
#include <avahi-core/log.h>
106
#include <avahi-common/simple-watch.h>
107
#include <avahi-common/malloc.h>
108
#include <avahi-common/error.h>
109
110
/* GnuTLS */
111
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
112
functions:
113
gnutls_*
114
init_gnutls_session(),
115
GNUTLS_* */
116
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
119
120
/* GPGME */
121
#include <gpgme.h> /* All GPGME types, constants and
122
functions:
123
gpgme_*
124
GPGME_PROTOCOL_OpenPGP,
125
GPG_ERR_NO_* */
126
127
#define BUFFER_SIZE 256
128
129
#define PATHDIR "/conf/conf.d/mandos"
130
#define SECKEY "seckey.txt"
131
#define PUBKEY "pubkey.txt"
132
#define HOOKDIR "/lib/mandos/network-hooks.d"
133
134
bool debug = false;
135
static const char mandos_protocol_version[] = "1";
136
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
138
static const char sys_class_net[] = "/sys/class/net";
139
char *connect_to = NULL;
140
const char *hookdir = HOOKDIR;
141
uid_t uid = 65534;
142
gid_t gid = 65534;
143
144
/* Doubly linked list that need to be circularly linked when used */
145
typedef struct server{
146
const char *ip;
147
in_port_t port;
148
AvahiIfIndex if_index;
149
int af;
150
struct timespec last_seen;
151
struct server *next;
152
struct server *prev;
153
} server;
154
155
/* Used for passing in values through the Avahi callback functions */
156
typedef struct {
157
AvahiServer *server;
158
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
gnutls_dh_params_t dh_params;
161
const char *priority;
162
gpgme_ctx_t ctx;
163
server *current_server;
164
char *interfaces;
165
size_t interfaces_size;
166
} mandos_context;
167
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
170
171
sig_atomic_t quit_now = 0;
172
int signal_received = 0;
173
174
/* Function to use when printing errors */
175
void perror_plus(const char *print_text){
176
int e = errno;
177
fprintf(stderr, "Mandos plugin %s: ",
178
program_invocation_short_name);
179
errno = e;
180
perror(print_text);
181
}
182
183
__attribute__((format (gnu_printf, 2, 3)))
184
int fprintf_plus(FILE *stream, const char *format, ...){
185
va_list ap;
186
va_start (ap, format);
187
188
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
program_invocation_short_name));
190
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
191
}
192
193
/*
194
* Make additional room in "buffer" for at least BUFFER_SIZE more
195
* bytes. "buffer_capacity" is how much is currently allocated,
196
* "buffer_length" is how much is already used.
197
*/
198
size_t incbuffer(char **buffer, size_t buffer_length,
199
size_t buffer_capacity){
200
if(buffer_length + BUFFER_SIZE > buffer_capacity){
201
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
202
if(new_buf == NULL){
203
int old_errno = errno;
204
free(*buffer);
205
errno = old_errno;
206
*buffer = NULL;
207
return 0;
208
}
209
*buffer = new_buf;
210
buffer_capacity += BUFFER_SIZE;
211
}
212
return buffer_capacity;
213
}
214
215
/* Add server to set of servers to retry periodically */
216
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
217
int af, server **current_server){
218
int ret;
219
server *new_server = malloc(sizeof(server));
220
if(new_server == NULL){
221
perror_plus("malloc");
222
return false;
223
}
224
*new_server = (server){ .ip = strdup(ip),
225
.port = port,
226
.if_index = if_index,
227
.af = af };
228
if(new_server->ip == NULL){
229
perror_plus("strdup");
230
return false;
231
}
232
/* Special case of first server */
233
if(*current_server == NULL){
234
new_server->next = new_server;
235
new_server->prev = new_server;
236
*current_server = new_server;
237
/* Place the new server last in the list */
238
} else {
239
new_server->next = *current_server;
240
new_server->prev = (*current_server)->prev;
241
new_server->prev->next = new_server;
242
(*current_server)->prev = new_server;
243
}
244
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
245
if(ret == -1){
246
perror_plus("clock_gettime");
247
return false;
248
}
249
return true;
250
}
251
252
/*
253
* Initialize GPGME.
254
*/
255
static bool init_gpgme(const char *seckey, const char *pubkey,
256
const char *tempdir, mandos_context *mc){
257
gpgme_error_t rc;
258
gpgme_engine_info_t engine_info;
259
260
/*
261
* Helper function to insert pub and seckey to the engine keyring.
262
*/
263
bool import_key(const char *filename){
264
int ret;
265
int fd;
266
gpgme_data_t pgp_data;
267
268
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
269
if(fd == -1){
270
perror_plus("open");
271
return false;
272
}
273
274
rc = gpgme_data_new_from_fd(&pgp_data, fd);
275
if(rc != GPG_ERR_NO_ERROR){
276
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
278
return false;
279
}
280
281
rc = gpgme_op_import(mc->ctx, pgp_data);
282
if(rc != GPG_ERR_NO_ERROR){
283
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
284
gpgme_strsource(rc), gpgme_strerror(rc));
285
return false;
286
}
287
288
ret = (int)TEMP_FAILURE_RETRY(close(fd));
289
if(ret == -1){
290
perror_plus("close");
291
}
292
gpgme_data_release(pgp_data);
293
return true;
294
}
295
296
if(debug){
297
fprintf_plus(stderr, "Initializing GPGME\n");
298
}
299
300
/* Init GPGME */
301
gpgme_check_version(NULL);
302
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
303
if(rc != GPG_ERR_NO_ERROR){
304
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
305
gpgme_strsource(rc), gpgme_strerror(rc));
306
return false;
307
}
308
309
/* Set GPGME home directory for the OpenPGP engine only */
310
rc = gpgme_get_engine_info(&engine_info);
311
if(rc != GPG_ERR_NO_ERROR){
312
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
313
gpgme_strsource(rc), gpgme_strerror(rc));
314
return false;
315
}
316
while(engine_info != NULL){
317
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
318
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
319
engine_info->file_name, tempdir);
320
break;
321
}
322
engine_info = engine_info->next;
323
}
324
if(engine_info == NULL){
325
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
326
tempdir);
327
return false;
328
}
329
330
/* Create new GPGME "context" */
331
rc = gpgme_new(&(mc->ctx));
332
if(rc != GPG_ERR_NO_ERROR){
333
fprintf_plus(stderr, "Mandos plugin mandos-client: "
334
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
335
gpgme_strerror(rc));
336
return false;
337
}
338
339
if(not import_key(pubkey) or not import_key(seckey)){
340
return false;
341
}
342
343
return true;
344
}
345
346
/*
347
* Decrypt OpenPGP data.
348
* Returns -1 on error
349
*/
350
static ssize_t pgp_packet_decrypt(const char *cryptotext,
351
size_t crypto_size,
352
char **plaintext,
353
mandos_context *mc){
354
gpgme_data_t dh_crypto, dh_plain;
355
gpgme_error_t rc;
356
ssize_t ret;
357
size_t plaintext_capacity = 0;
358
ssize_t plaintext_length = 0;
359
360
if(debug){
361
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
362
}
363
364
/* Create new GPGME data buffer from memory cryptotext */
365
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
366
0);
367
if(rc != GPG_ERR_NO_ERROR){
368
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
369
gpgme_strsource(rc), gpgme_strerror(rc));
370
return -1;
371
}
372
373
/* Create new empty GPGME data buffer for the plaintext */
374
rc = gpgme_data_new(&dh_plain);
375
if(rc != GPG_ERR_NO_ERROR){
376
fprintf_plus(stderr, "Mandos plugin mandos-client: "
377
"bad gpgme_data_new: %s: %s\n",
378
gpgme_strsource(rc), gpgme_strerror(rc));
379
gpgme_data_release(dh_crypto);
380
return -1;
381
}
382
383
/* Decrypt data from the cryptotext data buffer to the plaintext
384
data buffer */
385
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
386
if(rc != GPG_ERR_NO_ERROR){
387
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
388
gpgme_strsource(rc), gpgme_strerror(rc));
389
plaintext_length = -1;
390
if(debug){
391
gpgme_decrypt_result_t result;
392
result = gpgme_op_decrypt_result(mc->ctx);
393
if(result == NULL){
394
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
395
} else {
396
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
397
result->unsupported_algorithm);
398
fprintf_plus(stderr, "Wrong key usage: %u\n",
399
result->wrong_key_usage);
400
if(result->file_name != NULL){
401
fprintf_plus(stderr, "File name: %s\n", result->file_name);
402
}
403
gpgme_recipient_t recipient;
404
recipient = result->recipients;
405
while(recipient != NULL){
406
fprintf_plus(stderr, "Public key algorithm: %s\n",
407
gpgme_pubkey_algo_name
408
(recipient->pubkey_algo));
409
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
410
fprintf_plus(stderr, "Secret key available: %s\n",
411
recipient->status == GPG_ERR_NO_SECKEY
412
? "No" : "Yes");
413
recipient = recipient->next;
414
}
415
}
416
}
417
goto decrypt_end;
418
}
419
420
if(debug){
421
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
422
}
423
424
/* Seek back to the beginning of the GPGME plaintext data buffer */
425
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
426
perror_plus("gpgme_data_seek");
427
plaintext_length = -1;
428
goto decrypt_end;
429
}
430
431
*plaintext = NULL;
432
while(true){
433
plaintext_capacity = incbuffer(plaintext,
434
(size_t)plaintext_length,
435
plaintext_capacity);
436
if(plaintext_capacity == 0){
437
perror_plus("incbuffer");
438
plaintext_length = -1;
439
goto decrypt_end;
440
}
441
442
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
443
BUFFER_SIZE);
444
/* Print the data, if any */
445
if(ret == 0){
446
/* EOF */
447
break;
448
}
449
if(ret < 0){
450
perror_plus("gpgme_data_read");
451
plaintext_length = -1;
452
goto decrypt_end;
453
}
454
plaintext_length += ret;
455
}
456
457
if(debug){
458
fprintf_plus(stderr, "Decrypted password is: ");
459
for(ssize_t i = 0; i < plaintext_length; i++){
460
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
461
}
462
fprintf(stderr, "\n");
463
}
464
465
decrypt_end:
466
467
/* Delete the GPGME cryptotext data buffer */
468
gpgme_data_release(dh_crypto);
469
470
/* Delete the GPGME plaintext data buffer */
471
gpgme_data_release(dh_plain);
472
return plaintext_length;
473
}
474
475
static const char * safer_gnutls_strerror(int value){
476
const char *ret = gnutls_strerror(value);
477
if(ret == NULL)
478
ret = "(unknown)";
479
return ret;
480
}
481
482
/* GnuTLS log function callback */
483
static void debuggnutls(__attribute__((unused)) int level,
484
const char* string){
485
fprintf_plus(stderr, "GnuTLS: %s", string);
486
}
487
488
static int init_gnutls_global(const char *pubkeyfilename,
489
const char *seckeyfilename,
490
mandos_context *mc){
491
int ret;
492
493
if(debug){
494
fprintf_plus(stderr, "Initializing GnuTLS\n");
495
}
496
497
ret = gnutls_global_init();
498
if(ret != GNUTLS_E_SUCCESS){
499
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
500
safer_gnutls_strerror(ret));
501
return -1;
502
}
503
504
if(debug){
505
/* "Use a log level over 10 to enable all debugging options."
506
* - GnuTLS manual
507
*/
508
gnutls_global_set_log_level(11);
509
gnutls_global_set_log_function(debuggnutls);
510
}
511
512
/* OpenPGP credentials */
513
ret = gnutls_certificate_allocate_credentials(&mc->cred);
514
if(ret != GNUTLS_E_SUCCESS){
515
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
516
safer_gnutls_strerror(ret));
517
gnutls_global_deinit();
518
return -1;
519
}
520
521
if(debug){
522
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
523
" secret key %s as GnuTLS credentials\n",
524
pubkeyfilename,
525
seckeyfilename);
526
}
527
528
ret = gnutls_certificate_set_openpgp_key_file
529
(mc->cred, pubkeyfilename, seckeyfilename,
530
GNUTLS_OPENPGP_FMT_BASE64);
531
if(ret != GNUTLS_E_SUCCESS){
532
fprintf_plus(stderr,
533
"Error[%d] while reading the OpenPGP key pair ('%s',"
534
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
535
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
536
safer_gnutls_strerror(ret));
537
goto globalfail;
538
}
539
540
/* GnuTLS server initialization */
541
ret = gnutls_dh_params_init(&mc->dh_params);
542
if(ret != GNUTLS_E_SUCCESS){
543
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
544
" initialization: %s\n",
545
safer_gnutls_strerror(ret));
546
goto globalfail;
547
}
548
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
549
if(ret != GNUTLS_E_SUCCESS){
550
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
551
safer_gnutls_strerror(ret));
552
goto globalfail;
553
}
554
555
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
556
557
return 0;
558
559
globalfail:
560
561
gnutls_certificate_free_credentials(mc->cred);
562
gnutls_global_deinit();
563
gnutls_dh_params_deinit(mc->dh_params);
564
return -1;
565
}
566
567
static int init_gnutls_session(gnutls_session_t *session,
568
mandos_context *mc){
569
int ret;
570
/* GnuTLS session creation */
571
do {
572
ret = gnutls_init(session, GNUTLS_SERVER);
573
if(quit_now){
574
return -1;
575
}
576
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
577
if(ret != GNUTLS_E_SUCCESS){
578
fprintf_plus(stderr,
579
"Error in GnuTLS session initialization: %s\n",
580
safer_gnutls_strerror(ret));
581
}
582
583
{
584
const char *err;
585
do {
586
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
587
if(quit_now){
588
gnutls_deinit(*session);
589
return -1;
590
}
591
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
592
if(ret != GNUTLS_E_SUCCESS){
593
fprintf_plus(stderr, "Syntax error at: %s\n", err);
594
fprintf_plus(stderr, "GnuTLS error: %s\n",
595
safer_gnutls_strerror(ret));
596
gnutls_deinit(*session);
597
return -1;
598
}
599
}
600
601
do {
602
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
603
mc->cred);
604
if(quit_now){
605
gnutls_deinit(*session);
606
return -1;
607
}
608
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
609
if(ret != GNUTLS_E_SUCCESS){
610
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
611
safer_gnutls_strerror(ret));
612
gnutls_deinit(*session);
613
return -1;
614
}
615
616
/* ignore client certificate if any. */
617
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
618
619
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
620
621
return 0;
622
}
623
624
/* Avahi log function callback */
625
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
626
__attribute__((unused)) const char *txt){}
627
628
/* Called when a Mandos server is found */
629
static int start_mandos_communication(const char *ip, in_port_t port,
630
AvahiIfIndex if_index,
631
int af, mandos_context *mc){
632
int ret, tcp_sd = -1;
633
ssize_t sret;
634
union {
635
struct sockaddr_in in;
636
struct sockaddr_in6 in6;
637
} to;
638
char *buffer = NULL;
639
char *decrypted_buffer = NULL;
640
size_t buffer_length = 0;
641
size_t buffer_capacity = 0;
642
size_t written;
643
int retval = -1;
644
gnutls_session_t session;
645
int pf; /* Protocol family */
646
647
errno = 0;
648
649
if(quit_now){
650
errno = EINTR;
651
return -1;
652
}
653
654
switch(af){
655
case AF_INET6:
656
pf = PF_INET6;
657
break;
658
case AF_INET:
659
pf = PF_INET;
660
break;
661
default:
662
fprintf_plus(stderr, "Bad address family: %d\n", af);
663
errno = EINVAL;
664
return -1;
665
}
666
667
/* If the interface is specified and we have a list of interfaces */
668
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
669
/* Check if the interface is one of the interfaces we are using */
670
bool match = false;
671
{
672
char *interface = NULL;
673
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
674
interface))){
675
if(if_nametoindex(interface) == (unsigned int)if_index){
676
match = true;
677
break;
678
}
679
}
680
}
681
if(not match){
682
/* This interface does not match any in the list, so we don't
683
connect to the server */
684
if(debug){
685
char interface[IF_NAMESIZE];
686
if(if_indextoname((unsigned int)if_index, interface) == NULL){
687
perror_plus("if_indextoname");
688
} else {
689
fprintf_plus(stderr, "Skipping server on non-used interface"
690
" \"%s\"\n",
691
if_indextoname((unsigned int)if_index,
692
interface));
693
}
694
}
695
return -1;
696
}
697
}
698
699
ret = init_gnutls_session(&session, mc);
700
if(ret != 0){
701
return -1;
702
}
703
704
if(debug){
705
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
706
PRIuMAX "\n", ip, (uintmax_t)port);
707
}
708
709
tcp_sd = socket(pf, SOCK_STREAM, 0);
710
if(tcp_sd < 0){
711
int e = errno;
712
perror_plus("socket");
713
errno = e;
714
goto mandos_end;
715
}
716
717
if(quit_now){
718
errno = EINTR;
719
goto mandos_end;
720
}
721
722
memset(&to, 0, sizeof(to));
723
if(af == AF_INET6){
724
to.in6.sin6_family = (sa_family_t)af;
725
ret = inet_pton(af, ip, &to.in6.sin6_addr);
726
} else { /* IPv4 */
727
to.in.sin_family = (sa_family_t)af;
728
ret = inet_pton(af, ip, &to.in.sin_addr);
729
}
730
if(ret < 0 ){
731
int e = errno;
732
perror_plus("inet_pton");
733
errno = e;
734
goto mandos_end;
735
}
736
if(ret == 0){
737
int e = errno;
738
fprintf_plus(stderr, "Bad address: %s\n", ip);
739
errno = e;
740
goto mandos_end;
741
}
742
if(af == AF_INET6){
743
to.in6.sin6_port = htons(port);
744
#ifdef __GNUC__
745
#pragma GCC diagnostic push
746
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
747
#endif
748
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
749
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */
750
#ifdef __GNUC__
751
#pragma GCC diagnostic pop
752
#endif
753
if(if_index == AVAHI_IF_UNSPEC){
754
fprintf_plus(stderr, "An IPv6 link-local address is"
755
" incomplete without a network interface\n");
756
errno = EINVAL;
757
goto mandos_end;
758
}
759
/* Set the network interface number as scope */
760
to.in6.sin6_scope_id = (uint32_t)if_index;
761
}
762
} else {
763
to.in.sin_port = htons(port);
764
}
765
766
if(quit_now){
767
errno = EINTR;
768
goto mandos_end;
769
}
770
771
if(debug){
772
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
773
char interface[IF_NAMESIZE];
774
if(if_indextoname((unsigned int)if_index, interface) == NULL){
775
perror_plus("if_indextoname");
776
} else {
777
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
778
"\n", ip, interface, (uintmax_t)port);
779
}
780
} else {
781
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
782
ip, (uintmax_t)port);
783
}
784
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
785
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
786
const char *pcret;
787
if(af == AF_INET6){
788
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
789
sizeof(addrstr));
790
} else {
791
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
792
sizeof(addrstr));
793
}
794
if(pcret == NULL){
795
perror_plus("inet_ntop");
796
} else {
797
if(strcmp(addrstr, ip) != 0){
798
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
799
}
800
}
801
}
802
803
if(quit_now){
804
errno = EINTR;
805
goto mandos_end;
806
}
807
808
if(af == AF_INET6){
809
ret = connect(tcp_sd, &to.in6, sizeof(to));
810
} else {
811
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
812
}
813
if(ret < 0){
814
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
815
int e = errno;
816
perror_plus("connect");
817
errno = e;
818
}
819
goto mandos_end;
820
}
821
822
if(quit_now){
823
errno = EINTR;
824
goto mandos_end;
825
}
826
827
const char *out = mandos_protocol_version;
828
written = 0;
829
while(true){
830
size_t out_size = strlen(out);
831
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
832
out_size - written));
833
if(ret == -1){
834
int e = errno;
835
perror_plus("write");
836
errno = e;
837
goto mandos_end;
838
}
839
written += (size_t)ret;
840
if(written < out_size){
841
continue;
842
} else {
843
if(out == mandos_protocol_version){
844
written = 0;
845
out = "\r\n";
846
} else {
847
break;
848
}
849
}
850
851
if(quit_now){
852
errno = EINTR;
853
goto mandos_end;
854
}
855
}
856
857
if(debug){
858
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
859
}
860
861
if(quit_now){
862
errno = EINTR;
863
goto mandos_end;
864
}
865
866
/* This casting via intptr_t is to eliminate warning about casting
867
an int to a pointer type. This is exactly how the GnuTLS Guile
868
function "set-session-transport-fd!" does it. */
869
gnutls_transport_set_ptr(session,
870
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
871
872
if(quit_now){
873
errno = EINTR;
874
goto mandos_end;
875
}
876
877
do {
878
ret = gnutls_handshake(session);
879
if(quit_now){
880
errno = EINTR;
881
goto mandos_end;
882
}
883
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
884
885
if(ret != GNUTLS_E_SUCCESS){
886
if(debug){
887
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
888
gnutls_perror(ret);
889
}
890
errno = EPROTO;
891
goto mandos_end;
892
}
893
894
/* Read OpenPGP packet that contains the wanted password */
895
896
if(debug){
897
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
898
" %s\n", ip);
899
}
900
901
while(true){
902
903
if(quit_now){
904
errno = EINTR;
905
goto mandos_end;
906
}
907
908
buffer_capacity = incbuffer(&buffer, buffer_length,
909
buffer_capacity);
910
if(buffer_capacity == 0){
911
int e = errno;
912
perror_plus("incbuffer");
913
errno = e;
914
goto mandos_end;
915
}
916
917
if(quit_now){
918
errno = EINTR;
919
goto mandos_end;
920
}
921
922
sret = gnutls_record_recv(session, buffer+buffer_length,
923
BUFFER_SIZE);
924
if(sret == 0){
925
break;
926
}
927
if(sret < 0){
928
switch(sret){
929
case GNUTLS_E_INTERRUPTED:
930
case GNUTLS_E_AGAIN:
931
break;
932
case GNUTLS_E_REHANDSHAKE:
933
do {
934
ret = gnutls_handshake(session);
935
936
if(quit_now){
937
errno = EINTR;
938
goto mandos_end;
939
}
940
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
941
if(ret < 0){
942
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
943
"***\n");
944
gnutls_perror(ret);
945
errno = EPROTO;
946
goto mandos_end;
947
}
948
break;
949
default:
950
fprintf_plus(stderr, "Unknown error while reading data from"
951
" encrypted session with Mandos server\n");
952
gnutls_bye(session, GNUTLS_SHUT_RDWR);
953
errno = EIO;
954
goto mandos_end;
955
}
956
} else {
957
buffer_length += (size_t) sret;
958
}
959
}
960
961
if(debug){
962
fprintf_plus(stderr, "Closing TLS session\n");
963
}
964
965
if(quit_now){
966
errno = EINTR;
967
goto mandos_end;
968
}
969
970
do {
971
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
972
if(quit_now){
973
errno = EINTR;
974
goto mandos_end;
975
}
976
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
977
978
if(buffer_length > 0){
979
ssize_t decrypted_buffer_size;
980
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
981
&decrypted_buffer, mc);
982
if(decrypted_buffer_size >= 0){
983
984
written = 0;
985
while(written < (size_t) decrypted_buffer_size){
986
if(quit_now){
987
errno = EINTR;
988
goto mandos_end;
989
}
990
991
ret = (int)fwrite(decrypted_buffer + written, 1,
992
(size_t)decrypted_buffer_size - written,
993
stdout);
994
if(ret == 0 and ferror(stdout)){
995
int e = errno;
996
if(debug){
997
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
998
strerror(errno));
999
}
1000
errno = e;
1001
goto mandos_end;
1002
}
1003
written += (size_t)ret;
1004
}
1005
retval = 0;
1006
}
1007
}
1008
1009
/* Shutdown procedure */
1010
1011
mandos_end:
1012
{
1013
int e = errno;
1014
free(decrypted_buffer);
1015
free(buffer);
1016
if(tcp_sd >= 0){
1017
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1018
}
1019
if(ret == -1){
1020
if(e == 0){
1021
e = errno;
1022
}
1023
perror_plus("close");
1024
}
1025
gnutls_deinit(session);
1026
errno = e;
1027
if(quit_now){
1028
errno = EINTR;
1029
retval = -1;
1030
}
1031
}
1032
return retval;
1033
}
1034
1035
static void resolve_callback(AvahiSServiceResolver *r,
1036
AvahiIfIndex interface,
1037
AvahiProtocol proto,
1038
AvahiResolverEvent event,
1039
const char *name,
1040
const char *type,
1041
const char *domain,
1042
const char *host_name,
1043
const AvahiAddress *address,
1044
uint16_t port,
1045
AVAHI_GCC_UNUSED AvahiStringList *txt,
1046
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1047
flags,
1048
void* mc){
1049
if(r == NULL){
1050
return;
1051
}
1052
1053
/* Called whenever a service has been resolved successfully or
1054
timed out */
1055
1056
if(quit_now){
1057
return;
1058
}
1059
1060
switch(event){
1061
default:
1062
case AVAHI_RESOLVER_FAILURE:
1063
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1064
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1065
domain,
1066
avahi_strerror(avahi_server_errno
1067
(((mandos_context*)mc)->server)));
1068
break;
1069
1070
case AVAHI_RESOLVER_FOUND:
1071
{
1072
char ip[AVAHI_ADDRESS_STR_MAX];
1073
avahi_address_snprint(ip, sizeof(ip), address);
1074
if(debug){
1075
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1076
PRIdMAX ") on port %" PRIu16 "\n", name,
1077
host_name, ip, (intmax_t)interface, port);
1078
}
1079
int ret = start_mandos_communication(ip, (in_port_t)port,
1080
interface,
1081
avahi_proto_to_af(proto),
1082
mc);
1083
if(ret == 0){
1084
avahi_simple_poll_quit(simple_poll);
1085
} else {
1086
if(not add_server(ip, (in_port_t)port, interface,
1087
avahi_proto_to_af(proto),
1088
&((mandos_context*)mc)->current_server)){
1089
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1090
" list\n", name);
1091
}
1092
}
1093
}
1094
}
1095
avahi_s_service_resolver_free(r);
1096
}
1097
1098
static void browse_callback(AvahiSServiceBrowser *b,
1099
AvahiIfIndex interface,
1100
AvahiProtocol protocol,
1101
AvahiBrowserEvent event,
1102
const char *name,
1103
const char *type,
1104
const char *domain,
1105
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1106
flags,
1107
void* mc){
1108
if(b == NULL){
1109
return;
1110
}
1111
1112
/* Called whenever a new services becomes available on the LAN or
1113
is removed from the LAN */
1114
1115
if(quit_now){
1116
return;
1117
}
1118
1119
switch(event){
1120
default:
1121
case AVAHI_BROWSER_FAILURE:
1122
1123
fprintf_plus(stderr, "(Avahi browser) %s\n",
1124
avahi_strerror(avahi_server_errno
1125
(((mandos_context*)mc)->server)));
1126
avahi_simple_poll_quit(simple_poll);
1127
return;
1128
1129
case AVAHI_BROWSER_NEW:
1130
/* We ignore the returned Avahi resolver object. In the callback
1131
function we free it. If the Avahi server is terminated before
1132
the callback function is called the Avahi server will free the
1133
resolver for us. */
1134
1135
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1136
interface, protocol, name, type,
1137
domain, protocol, 0,
1138
resolve_callback, mc) == NULL)
1139
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1140
" %s\n", name,
1141
avahi_strerror(avahi_server_errno
1142
(((mandos_context*)mc)->server)));
1143
break;
1144
1145
case AVAHI_BROWSER_REMOVE:
1146
break;
1147
1148
case AVAHI_BROWSER_ALL_FOR_NOW:
1149
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1150
if(debug){
1151
fprintf_plus(stderr, "No Mandos server found, still"
1152
" searching...\n");
1153
}
1154
break;
1155
}
1156
}
1157
1158
/* Signal handler that stops main loop after SIGTERM */
1159
static void handle_sigterm(int sig){
1160
if(quit_now){
1161
return;
1162
}
1163
quit_now = 1;
1164
signal_received = sig;
1165
int old_errno = errno;
1166
/* set main loop to exit */
1167
if(simple_poll != NULL){
1168
avahi_simple_poll_quit(simple_poll);
1169
}
1170
errno = old_errno;
1171
}
1172
1173
bool get_flags(const char *ifname, struct ifreq *ifr){
1174
int ret;
1175
error_t ret_errno;
1176
1177
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1178
if(s < 0){
1179
ret_errno = errno;
1180
perror_plus("socket");
1181
errno = ret_errno;
1182
return false;
1183
}
1184
strcpy(ifr->ifr_name, ifname);
1185
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1186
if(ret == -1){
1187
if(debug){
1188
ret_errno = errno;
1189
perror_plus("ioctl SIOCGIFFLAGS");
1190
errno = ret_errno;
1191
}
1192
return false;
1193
}
1194
return true;
1195
}
1196
1197
bool good_flags(const char *ifname, const struct ifreq *ifr){
1198
1199
/* Reject the loopback device */
1200
if(ifr->ifr_flags & IFF_LOOPBACK){
1201
if(debug){
1202
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1203
ifname);
1204
}
1205
return false;
1206
}
1207
/* Accept point-to-point devices only if connect_to is specified */
1208
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1209
if(debug){
1210
fprintf_plus(stderr, "Accepting point-to-point interface"
1211
" \"%s\"\n", ifname);
1212
}
1213
return true;
1214
}
1215
/* Otherwise, reject non-broadcast-capable devices */
1216
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1217
if(debug){
1218
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1219
" \"%s\"\n", ifname);
1220
}
1221
return false;
1222
}
1223
/* Reject non-ARP interfaces (including dummy interfaces) */
1224
if(ifr->ifr_flags & IFF_NOARP){
1225
if(debug){
1226
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1227
ifname);
1228
}
1229
return false;
1230
}
1231
1232
/* Accept this device */
1233
if(debug){
1234
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1235
}
1236
return true;
1237
}
1238
1239
/*
1240
* This function determines if a directory entry in /sys/class/net
1241
* corresponds to an acceptable network device.
1242
* (This function is passed to scandir(3) as a filter function.)
1243
*/
1244
int good_interface(const struct dirent *if_entry){
1245
if(if_entry->d_name[0] == '.'){
1246
return 0;
1247
}
1248
1249
struct ifreq ifr;
1250
if(not get_flags(if_entry->d_name, &ifr)){
1251
if(debug){
1252
fprintf_plus(stderr, "Failed to get flags for interface "
1253
"\"%s\"\n", if_entry->d_name);
1254
}
1255
return 0;
1256
}
1257
1258
if(not good_flags(if_entry->d_name, &ifr)){
1259
return 0;
1260
}
1261
return 1;
1262
}
1263
1264
/*
1265
* This function determines if a network interface is up.
1266
*/
1267
bool interface_is_up(const char *interface){
1268
struct ifreq ifr;
1269
if(not get_flags(interface, &ifr)){
1270
if(debug){
1271
fprintf_plus(stderr, "Failed to get flags for interface "
1272
"\"%s\"\n", interface);
1273
}
1274
return false;
1275
}
1276
1277
return (bool)(ifr.ifr_flags & IFF_UP);
1278
}
1279
1280
/*
1281
* This function determines if a network interface is running
1282
*/
1283
bool interface_is_running(const char *interface){
1284
struct ifreq ifr;
1285
if(not get_flags(interface, &ifr)){
1286
if(debug){
1287
fprintf_plus(stderr, "Failed to get flags for interface "
1288
"\"%s\"\n", interface);
1289
}
1290
return false;
1291
}
1292
1293
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1294
}
1295
1296
int notdotentries(const struct dirent *direntry){
1297
/* Skip "." and ".." */
1298
if(direntry->d_name[0] == '.'
1299
and (direntry->d_name[1] == '\0'
1300
or (direntry->d_name[1] == '.'
1301
and direntry->d_name[2] == '\0'))){
1302
return 0;
1303
}
1304
return 1;
1305
}
1306
1307
/* Is this directory entry a runnable program? */
1308
int runnable_hook(const struct dirent *direntry){
1309
int ret;
1310
size_t sret;
1311
struct stat st;
1312
1313
if((direntry->d_name)[0] == '\0'){
1314
/* Empty name? */
1315
return 0;
1316
}
1317
1318
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1319
"abcdefghijklmnopqrstuvwxyz"
1320
"0123456789"
1321
"_-");
1322
if((direntry->d_name)[sret] != '\0'){
1323
/* Contains non-allowed characters */
1324
if(debug){
1325
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1326
direntry->d_name);
1327
}
1328
return 0;
1329
}
1330
1331
char *fullname = NULL;
1332
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1333
if(ret < 0){
1334
perror_plus("asprintf");
1335
return 0;
1336
}
1337
1338
ret = stat(fullname, &st);
1339
if(ret == -1){
1340
if(debug){
1341
perror_plus("Could not stat hook");
1342
}
1343
return 0;
1344
}
1345
if(not (S_ISREG(st.st_mode))){
1346
/* Not a regular file */
1347
if(debug){
1348
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1349
direntry->d_name);
1350
}
1351
return 0;
1352
}
1353
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1354
/* Not executable */
1355
if(debug){
1356
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1357
direntry->d_name);
1358
}
1359
return 0;
1360
}
1361
if(debug){
1362
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1363
direntry->d_name);
1364
}
1365
return 1;
1366
}
1367
1368
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1369
mandos_context *mc){
1370
int ret;
1371
struct timespec now;
1372
struct timespec waited_time;
1373
intmax_t block_time;
1374
1375
while(true){
1376
if(mc->current_server == NULL){
1377
if (debug){
1378
fprintf_plus(stderr, "Wait until first server is found."
1379
" No timeout!\n");
1380
}
1381
ret = avahi_simple_poll_iterate(s, -1);
1382
} else {
1383
if (debug){
1384
fprintf_plus(stderr, "Check current_server if we should run"
1385
" it, or wait\n");
1386
}
1387
/* the current time */
1388
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1389
if(ret == -1){
1390
perror_plus("clock_gettime");
1391
return -1;
1392
}
1393
/* Calculating in ms how long time between now and server
1394
who we visted longest time ago. Now - last seen. */
1395
waited_time.tv_sec = (now.tv_sec
1396
- mc->current_server->last_seen.tv_sec);
1397
waited_time.tv_nsec = (now.tv_nsec
1398
- mc->current_server->last_seen.tv_nsec);
1399
/* total time is 10s/10,000ms.
1400
Converting to s from ms by dividing by 1,000,
1401
and ns to ms by dividing by 1,000,000. */
1402
block_time = ((retry_interval
1403
- ((intmax_t)waited_time.tv_sec * 1000))
1404
- ((intmax_t)waited_time.tv_nsec / 1000000));
1405
1406
if (debug){
1407
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1408
block_time);
1409
}
1410
1411
if(block_time <= 0){
1412
ret = start_mandos_communication(mc->current_server->ip,
1413
mc->current_server->port,
1414
mc->current_server->if_index,
1415
mc->current_server->af, mc);
1416
if(ret == 0){
1417
avahi_simple_poll_quit(s);
1418
return 0;
1419
}
1420
ret = clock_gettime(CLOCK_MONOTONIC,
1421
&mc->current_server->last_seen);
1422
if(ret == -1){
1423
perror_plus("clock_gettime");
1424
return -1;
1425
}
1426
mc->current_server = mc->current_server->next;
1427
block_time = 0; /* Call avahi to find new Mandos
1428
servers, but don't block */
1429
}
1430
1431
ret = avahi_simple_poll_iterate(s, (int)block_time);
1432
}
1433
if(ret != 0){
1434
if (ret > 0 or errno != EINTR){
1435
return (ret != 1) ? ret : 0;
1436
}
1437
}
1438
}
1439
}
1440
1441
/* Set effective uid to 0, return errno */
1442
error_t raise_privileges(void){
1443
error_t old_errno = errno;
1444
error_t ret_errno = 0;
1445
if(seteuid(0) == -1){
1446
ret_errno = errno;
1447
perror_plus("seteuid");
1448
}
1449
errno = old_errno;
1450
return ret_errno;
1451
}
1452
1453
/* Set effective and real user ID to 0. Return errno. */
1454
error_t raise_privileges_permanently(void){
1455
error_t old_errno = errno;
1456
error_t ret_errno = raise_privileges();
1457
if(ret_errno != 0){
1458
errno = old_errno;
1459
return ret_errno;
1460
}
1461
if(setuid(0) == -1){
1462
ret_errno = errno;
1463
perror_plus("seteuid");
1464
}
1465
errno = old_errno;
1466
return ret_errno;
1467
}
1468
1469
/* Set effective user ID to unprivileged saved user ID */
1470
error_t lower_privileges(void){
1471
error_t old_errno = errno;
1472
error_t ret_errno = 0;
1473
if(seteuid(uid) == -1){
1474
ret_errno = errno;
1475
perror_plus("seteuid");
1476
}
1477
errno = old_errno;
1478
return ret_errno;
1479
}
1480
1481
/* Lower privileges permanently */
1482
error_t lower_privileges_permanently(void){
1483
error_t old_errno = errno;
1484
error_t ret_errno = 0;
1485
if(setuid(uid) == -1){
1486
ret_errno = errno;
1487
perror_plus("setuid");
1488
}
1489
errno = old_errno;
1490
return ret_errno;
1491
}
1492
1493
bool run_network_hooks(const char *mode, const char *interface,
1494
const float delay){
1495
struct dirent **direntries;
1496
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1497
alphasort);
1498
if(numhooks == -1){
1499
if(errno == ENOENT){
1500
if(debug){
1501
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1502
" found\n", hookdir);
1503
}
1504
} else {
1505
perror_plus("scandir");
1506
}
1507
} else {
1508
struct dirent *direntry;
1509
int ret;
1510
int devnull = open("/dev/null", O_RDONLY);
1511
for(int i = 0; i < numhooks; i++){
1512
direntry = direntries[i];
1513
char *fullname = NULL;
1514
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1515
if(ret < 0){
1516
perror_plus("asprintf");
1517
continue;
1518
}
1519
if(debug){
1520
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1521
direntry->d_name);
1522
}
1523
pid_t hook_pid = fork();
1524
if(hook_pid == 0){
1525
/* Child */
1526
/* Raise privileges */
1527
raise_privileges_permanently();
1528
/* Set group */
1529
errno = 0;
1530
ret = setgid(0);
1531
if(ret == -1){
1532
perror_plus("setgid");
1533
}
1534
/* Reset supplementary groups */
1535
errno = 0;
1536
ret = setgroups(0, NULL);
1537
if(ret == -1){
1538
perror_plus("setgroups");
1539
}
1540
dup2(devnull, STDIN_FILENO);
1541
close(devnull);
1542
dup2(STDERR_FILENO, STDOUT_FILENO);
1543
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1544
if(ret == -1){
1545
perror_plus("setenv");
1546
_exit(EX_OSERR);
1547
}
1548
ret = setenv("DEVICE", interface, 1);
1549
if(ret == -1){
1550
perror_plus("setenv");
1551
_exit(EX_OSERR);
1552
}
1553
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1554
if(ret == -1){
1555
perror_plus("setenv");
1556
_exit(EX_OSERR);
1557
}
1558
ret = setenv("MODE", mode, 1);
1559
if(ret == -1){
1560
perror_plus("setenv");
1561
_exit(EX_OSERR);
1562
}
1563
char *delaystring;
1564
ret = asprintf(&delaystring, "%f", delay);
1565
if(ret == -1){
1566
perror_plus("asprintf");
1567
_exit(EX_OSERR);
1568
}
1569
ret = setenv("DELAY", delaystring, 1);
1570
if(ret == -1){
1571
free(delaystring);
1572
perror_plus("setenv");
1573
_exit(EX_OSERR);
1574
}
1575
free(delaystring);
1576
if(connect_to != NULL){
1577
ret = setenv("CONNECT", connect_to, 1);
1578
if(ret == -1){
1579
perror_plus("setenv");
1580
_exit(EX_OSERR);
1581
}
1582
}
1583
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1584
perror_plus("execl");
1585
_exit(EXIT_FAILURE);
1586
}
1587
} else {
1588
int status;
1589
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1590
perror_plus("waitpid");
1591
free(fullname);
1592
continue;
1593
}
1594
if(WIFEXITED(status)){
1595
if(WEXITSTATUS(status) != 0){
1596
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1597
" with status %d\n", direntry->d_name,
1598
WEXITSTATUS(status));
1599
free(fullname);
1600
continue;
1601
}
1602
} else if(WIFSIGNALED(status)){
1603
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1604
" signal %d\n", direntry->d_name,
1605
WTERMSIG(status));
1606
free(fullname);
1607
continue;
1608
} else {
1609
fprintf_plus(stderr, "Warning: network hook \"%s\""
1610
" crashed\n", direntry->d_name);
1611
free(fullname);
1612
continue;
1613
}
1614
}
1615
free(fullname);
1616
if(debug){
1617
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1618
direntry->d_name);
1619
}
1620
}
1621
close(devnull);
1622
}
1623
return true;
1624
}
1625
1626
error_t bring_up_interface(const char *const interface,
1627
const float delay){
1628
int sd = -1;
1629
error_t old_errno = errno;
1630
error_t ret_errno = 0;
1631
int ret, ret_setflags;
1632
struct ifreq network;
1633
unsigned int if_index = if_nametoindex(interface);
1634
if(if_index == 0){
1635
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1636
errno = old_errno;
1637
return ENXIO;
1638
}
1639
1640
if(quit_now){
1641
errno = old_errno;
1642
return EINTR;
1643
}
1644
1645
if(not interface_is_up(interface)){
1646
if(not get_flags(interface, &network) and debug){
1647
ret_errno = errno;
1648
fprintf_plus(stderr, "Failed to get flags for interface "
1649
"\"%s\"\n", interface);
1650
return ret_errno;
1651
}
1652
network.ifr_flags |= IFF_UP;
1653
1654
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1655
if(sd < 0){
1656
ret_errno = errno;
1657
perror_plus("socket");
1658
errno = old_errno;
1659
return ret_errno;
1660
}
1661
1662
if(quit_now){
1663
close(sd);
1664
errno = old_errno;
1665
return EINTR;
1666
}
1667
1668
if(debug){
1669
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1670
interface);
1671
}
1672
1673
/* Raise priviliges */
1674
raise_privileges();
1675
1676
#ifdef __linux__
1677
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1678
messages about the network interface to mess up the prompt */
1679
int ret_linux = klogctl(8, NULL, 5);
1680
bool restore_loglevel = true;
1681
if(ret_linux == -1){
1682
restore_loglevel = false;
1683
perror_plus("klogctl");
1684
}
1685
#endif /* __linux__ */
1686
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1687
ret_errno = errno;
1688
#ifdef __linux__
1689
if(restore_loglevel){
1690
ret_linux = klogctl(7, NULL, 0);
1691
if(ret_linux == -1){
1692
perror_plus("klogctl");
1693
}
1694
}
1695
#endif /* __linux__ */
1696
1697
/* Lower privileges */
1698
lower_privileges();
1699
1700
/* Close the socket */
1701
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1702
if(ret == -1){
1703
perror_plus("close");
1704
}
1705
1706
if(ret_setflags == -1){
1707
errno = ret_errno;
1708
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1709
errno = old_errno;
1710
return ret_errno;
1711
}
1712
} else if(debug){
1713
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1714
interface);
1715
}
1716
1717
/* Sleep checking until interface is running.
1718
Check every 0.25s, up to total time of delay */
1719
for(int i=0; i < delay * 4; i++){
1720
if(interface_is_running(interface)){
1721
break;
1722
}
1723
struct timespec sleeptime = { .tv_nsec = 250000000 };
1724
ret = nanosleep(&sleeptime, NULL);
1725
if(ret == -1 and errno != EINTR){
1726
perror_plus("nanosleep");
1727
}
1728
}
1729
1730
errno = old_errno;
1731
return 0;
1732
}
1733
1734
error_t take_down_interface(const char *const interface){
1735
error_t old_errno = errno;
1736
struct ifreq network;
1737
unsigned int if_index = if_nametoindex(interface);
1738
if(if_index == 0){
1739
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1740
errno = old_errno;
1741
return ENXIO;
1742
}
1743
if(interface_is_up(interface)){
1744
error_t ret_errno = 0;
1745
if(not get_flags(interface, &network) and debug){
1746
ret_errno = errno;
1747
fprintf_plus(stderr, "Failed to get flags for interface "
1748
"\"%s\"\n", interface);
1749
return ret_errno;
1750
}
1751
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1752
1753
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1754
if(sd < 0){
1755
ret_errno = errno;
1756
perror_plus("socket");
1757
errno = old_errno;
1758
return ret_errno;
1759
}
1760
1761
if(debug){
1762
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1763
interface);
1764
}
1765
1766
/* Raise priviliges */
1767
raise_privileges();
1768
1769
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1770
ret_errno = errno;
1771
1772
/* Lower privileges */
1773
lower_privileges();
1774
1775
/* Close the socket */
1776
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1777
if(ret == -1){
1778
perror_plus("close");
1779
}
1780
1781
if(ret_setflags == -1){
1782
errno = ret_errno;
1783
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1784
errno = old_errno;
1785
return ret_errno;
1786
}
1787
} else if(debug){
1788
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1789
interface);
1790
}
1791
1792
errno = old_errno;
1793
return 0;
1794
}
1795
1796
int main(int argc, char *argv[]){
1797
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1798
.priority = "SECURE256:!CTYPE-X.509:"
1799
"+CTYPE-OPENPGP", .current_server = NULL,
1800
.interfaces = NULL, .interfaces_size = 0 };
1801
AvahiSServiceBrowser *sb = NULL;
1802
error_t ret_errno;
1803
int ret;
1804
intmax_t tmpmax;
1805
char *tmp;
1806
int exitcode = EXIT_SUCCESS;
1807
char *interfaces_to_take_down = NULL;
1808
size_t interfaces_to_take_down_size = 0;
1809
char tempdir[] = "/tmp/mandosXXXXXX";
1810
bool tempdir_created = false;
1811
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1812
const char *seckey = PATHDIR "/" SECKEY;
1813
const char *pubkey = PATHDIR "/" PUBKEY;
1814
char *interfaces_hooks = NULL;
1815
1816
bool gnutls_initialized = false;
1817
bool gpgme_initialized = false;
1818
float delay = 2.5f;
1819
double retry_interval = 10; /* 10s between trying a server and
1820
retrying the same server again */
1821
1822
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1823
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1824
1825
uid = getuid();
1826
gid = getgid();
1827
1828
/* Lower any group privileges we might have, just to be safe */
1829
errno = 0;
1830
ret = setgid(gid);
1831
if(ret == -1){
1832
perror_plus("setgid");
1833
}
1834
1835
/* Lower user privileges (temporarily) */
1836
errno = 0;
1837
ret = seteuid(uid);
1838
if(ret == -1){
1839
perror_plus("seteuid");
1840
}
1841
1842
if(quit_now){
1843
goto end;
1844
}
1845
1846
{
1847
struct argp_option options[] = {
1848
{ .name = "debug", .key = 128,
1849
.doc = "Debug mode", .group = 3 },
1850
{ .name = "connect", .key = 'c',
1851
.arg = "ADDRESS:PORT",
1852
.doc = "Connect directly to a specific Mandos server",
1853
.group = 1 },
1854
{ .name = "interface", .key = 'i',
1855
.arg = "NAME",
1856
.doc = "Network interface that will be used to search for"
1857
" Mandos servers",
1858
.group = 1 },
1859
{ .name = "seckey", .key = 's',
1860
.arg = "FILE",
1861
.doc = "OpenPGP secret key file base name",
1862
.group = 1 },
1863
{ .name = "pubkey", .key = 'p',
1864
.arg = "FILE",
1865
.doc = "OpenPGP public key file base name",
1866
.group = 2 },
1867
{ .name = "dh-bits", .key = 129,
1868
.arg = "BITS",
1869
.doc = "Bit length of the prime number used in the"
1870
" Diffie-Hellman key exchange",
1871
.group = 2 },
1872
{ .name = "priority", .key = 130,
1873
.arg = "STRING",
1874
.doc = "GnuTLS priority string for the TLS handshake",
1875
.group = 1 },
1876
{ .name = "delay", .key = 131,
1877
.arg = "SECONDS",
1878
.doc = "Maximum delay to wait for interface startup",
1879
.group = 2 },
1880
{ .name = "retry", .key = 132,
1881
.arg = "SECONDS",
1882
.doc = "Retry interval used when denied by the Mandos server",
1883
.group = 2 },
1884
{ .name = "network-hook-dir", .key = 133,
1885
.arg = "DIR",
1886
.doc = "Directory where network hooks are located",
1887
.group = 2 },
1888
/*
1889
* These reproduce what we would get without ARGP_NO_HELP
1890
*/
1891
{ .name = "help", .key = '?',
1892
.doc = "Give this help list", .group = -1 },
1893
{ .name = "usage", .key = -3,
1894
.doc = "Give a short usage message", .group = -1 },
1895
{ .name = "version", .key = 'V',
1896
.doc = "Print program version", .group = -1 },
1897
{ .name = NULL }
1898
};
1899
1900
error_t parse_opt(int key, char *arg,
1901
struct argp_state *state){
1902
errno = 0;
1903
switch(key){
1904
case 128: /* --debug */
1905
debug = true;
1906
break;
1907
case 'c': /* --connect */
1908
connect_to = arg;
1909
break;
1910
case 'i': /* --interface */
1911
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1912
arg, (int)',');
1913
if(ret_errno != 0){
1914
argp_error(state, "%s", strerror(ret_errno));
1915
}
1916
break;
1917
case 's': /* --seckey */
1918
seckey = arg;
1919
break;
1920
case 'p': /* --pubkey */
1921
pubkey = arg;
1922
break;
1923
case 129: /* --dh-bits */
1924
errno = 0;
1925
tmpmax = strtoimax(arg, &tmp, 10);
1926
if(errno != 0 or tmp == arg or *tmp != '\0'
1927
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1928
argp_error(state, "Bad number of DH bits");
1929
}
1930
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1931
break;
1932
case 130: /* --priority */
1933
mc.priority = arg;
1934
break;
1935
case 131: /* --delay */
1936
errno = 0;
1937
delay = strtof(arg, &tmp);
1938
if(errno != 0 or tmp == arg or *tmp != '\0'){
1939
argp_error(state, "Bad delay");
1940
}
1941
case 132: /* --retry */
1942
errno = 0;
1943
retry_interval = strtod(arg, &tmp);
1944
if(errno != 0 or tmp == arg or *tmp != '\0'
1945
or (retry_interval * 1000) > INT_MAX
1946
or retry_interval < 0){
1947
argp_error(state, "Bad retry interval");
1948
}
1949
break;
1950
case 133: /* --network-hook-dir */
1951
hookdir = arg;
1952
break;
1953
/*
1954
* These reproduce what we would get without ARGP_NO_HELP
1955
*/
1956
case '?': /* --help */
1957
argp_state_help(state, state->out_stream,
1958
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1959
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1960
case -3: /* --usage */
1961
argp_state_help(state, state->out_stream,
1962
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1963
case 'V': /* --version */
1964
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1965
exit(argp_err_exit_status);
1966
break;
1967
default:
1968
return ARGP_ERR_UNKNOWN;
1969
}
1970
return errno;
1971
}
1972
1973
struct argp argp = { .options = options, .parser = parse_opt,
1974
.args_doc = "",
1975
.doc = "Mandos client -- Get and decrypt"
1976
" passwords from a Mandos server" };
1977
ret = argp_parse(&argp, argc, argv,
1978
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1979
switch(ret){
1980
case 0:
1981
break;
1982
case ENOMEM:
1983
default:
1984
errno = ret;
1985
perror_plus("argp_parse");
1986
exitcode = EX_OSERR;
1987
goto end;
1988
case EINVAL:
1989
exitcode = EX_USAGE;
1990
goto end;
1991
}
1992
}
1993
1994
{
1995
/* Work around Debian bug #633582:
1996
<http://bugs.debian.org/633582> */
1997
1998
/* Re-raise priviliges */
1999
if(raise_privileges() == 0){
2000
struct stat st;
2001
2002
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2003
int seckey_fd = open(seckey, O_RDONLY);
2004
if(seckey_fd == -1){
2005
perror_plus("open");
2006
} else {
2007
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2008
if(ret == -1){
2009
perror_plus("fstat");
2010
} else {
2011
if(S_ISREG(st.st_mode)
2012
and st.st_uid == 0 and st.st_gid == 0){
2013
ret = fchown(seckey_fd, uid, gid);
2014
if(ret == -1){
2015
perror_plus("fchown");
2016
}
2017
}
2018
}
2019
TEMP_FAILURE_RETRY(close(seckey_fd));
2020
}
2021
}
2022
2023
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2024
int pubkey_fd = open(pubkey, O_RDONLY);
2025
if(pubkey_fd == -1){
2026
perror_plus("open");
2027
} else {
2028
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2029
if(ret == -1){
2030
perror_plus("fstat");
2031
} else {
2032
if(S_ISREG(st.st_mode)
2033
and st.st_uid == 0 and st.st_gid == 0){
2034
ret = fchown(pubkey_fd, uid, gid);
2035
if(ret == -1){
2036
perror_plus("fchown");
2037
}
2038
}
2039
}
2040
TEMP_FAILURE_RETRY(close(pubkey_fd));
2041
}
2042
}
2043
2044
/* Lower privileges */
2045
lower_privileges();
2046
}
2047
}
2048
2049
/* Remove invalid interface names (except "none") */
2050
{
2051
char *interface = NULL;
2052
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2053
interface))){
2054
if(strcmp(interface, "none") != 0
2055
and if_nametoindex(interface) == 0){
2056
if(interface[0] != '\0'){
2057
fprintf_plus(stderr, "Not using nonexisting interface"
2058
" \"%s\"\n", interface);
2059
}
2060
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2061
interface = NULL;
2062
}
2063
}
2064
}
2065
2066
/* Run network hooks */
2067
{
2068
if(mc.interfaces != NULL){
2069
interfaces_hooks = malloc(mc.interfaces_size);
2070
if(interfaces_hooks == NULL){
2071
perror_plus("malloc");
2072
goto end;
2073
}
2074
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2075
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2076
}
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
2079
goto end;
2080
}
2081
}
2082
2083
if(not debug){
2084
avahi_set_log_function(empty_log);
2085
}
2086
2087
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2088
from the signal handler */
2089
/* Initialize the pseudo-RNG for Avahi */
2090
srand((unsigned int) time(NULL));
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
2093
fprintf_plus(stderr,
2094
"Avahi: Failed to create simple poll object.\n");
2095
exitcode = EX_UNAVAILABLE;
2096
goto end;
2097
}
2098
2099
sigemptyset(&sigterm_action.sa_mask);
2100
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2101
if(ret == -1){
2102
perror_plus("sigaddset");
2103
exitcode = EX_OSERR;
2104
goto end;
2105
}
2106
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2107
if(ret == -1){
2108
perror_plus("sigaddset");
2109
exitcode = EX_OSERR;
2110
goto end;
2111
}
2112
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2113
if(ret == -1){
2114
perror_plus("sigaddset");
2115
exitcode = EX_OSERR;
2116
goto end;
2117
}
2118
/* Need to check if the handler is SIG_IGN before handling:
2119
| [[info:libc:Initial Signal Actions]] |
2120
| [[info:libc:Basic Signal Handling]] |
2121
*/
2122
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2123
if(ret == -1){
2124
perror_plus("sigaction");
2125
return EX_OSERR;
2126
}
2127
if(old_sigterm_action.sa_handler != SIG_IGN){
2128
ret = sigaction(SIGINT, &sigterm_action, NULL);
2129
if(ret == -1){
2130
perror_plus("sigaction");
2131
exitcode = EX_OSERR;
2132
goto end;
2133
}
2134
}
2135
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2136
if(ret == -1){
2137
perror_plus("sigaction");
2138
return EX_OSERR;
2139
}
2140
if(old_sigterm_action.sa_handler != SIG_IGN){
2141
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2142
if(ret == -1){
2143
perror_plus("sigaction");
2144
exitcode = EX_OSERR;
2145
goto end;
2146
}
2147
}
2148
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2149
if(ret == -1){
2150
perror_plus("sigaction");
2151
return EX_OSERR;
2152
}
2153
if(old_sigterm_action.sa_handler != SIG_IGN){
2154
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2155
if(ret == -1){
2156
perror_plus("sigaction");
2157
exitcode = EX_OSERR;
2158
goto end;
2159
}
2160
}
2161
2162
/* If no interfaces were specified, make a list */
2163
if(mc.interfaces == NULL){
2164
struct dirent **direntries;
2165
/* Look for any good interfaces */
2166
ret = scandir(sys_class_net, &direntries, good_interface,
2167
alphasort);
2168
if(ret >= 1){
2169
/* Add all found interfaces to interfaces list */
2170
for(int i = 0; i < ret; ++i){
2171
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2172
direntries[i]->d_name);
2173
if(ret_errno != 0){
2174
errno = ret_errno;
2175
perror_plus("argz_add");
2176
continue;
2177
}
2178
if(debug){
2179
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2180
direntries[i]->d_name);
2181
}
2182
}
2183
free(direntries);
2184
} else {
2185
free(direntries);
2186
fprintf_plus(stderr, "Could not find a network interface\n");
2187
exitcode = EXIT_FAILURE;
2188
goto end;
2189
}
2190
}
2191
2192
/* Bring up interfaces which are down, and remove any "none"s */
2193
{
2194
char *interface = NULL;
2195
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2196
interface))){
2197
/* If interface name is "none", stop bringing up interfaces.
2198
Also remove all instances of "none" from the list */
2199
if(strcmp(interface, "none") == 0){
2200
argz_delete(&mc.interfaces, &mc.interfaces_size,
2201
interface);
2202
interface = NULL;
2203
while((interface = argz_next(mc.interfaces,
2204
mc.interfaces_size, interface))){
2205
if(strcmp(interface, "none") == 0){
2206
argz_delete(&mc.interfaces, &mc.interfaces_size,
2207
interface);
2208
interface = NULL;
2209
}
2210
}
2211
break;
2212
}
2213
bool interface_was_up = interface_is_up(interface);
2214
ret = bring_up_interface(interface, delay);
2215
if(not interface_was_up){
2216
if(ret != 0){
2217
errno = ret;
2218
perror_plus("Failed to bring up interface");
2219
} else {
2220
ret_errno = argz_add(&interfaces_to_take_down,
2221
&interfaces_to_take_down_size,
2222
interface);
2223
if(ret_errno != 0){
2224
errno = ret_errno;
2225
perror_plus("argz_add");
2226
}
2227
}
2228
}
2229
}
2230
if(debug and (interfaces_to_take_down == NULL)){
2231
fprintf_plus(stderr, "No interfaces were brought up\n");
2232
}
2233
}
2234
2235
/* If we only got one interface, explicitly use only that one */
2236
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2237
if(debug){
2238
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2239
mc.interfaces);
2240
}
2241
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2242
}
2243
2244
if(quit_now){
2245
goto end;
2246
}
2247
2248
ret = init_gnutls_global(pubkey, seckey, &mc);
2249
if(ret == -1){
2250
fprintf_plus(stderr, "init_gnutls_global failed\n");
2251
exitcode = EX_UNAVAILABLE;
2252
goto end;
2253
} else {
2254
gnutls_initialized = true;
2255
}
2256
2257
if(quit_now){
2258
goto end;
2259
}
2260
2261
if(mkdtemp(tempdir) == NULL){
2262
perror_plus("mkdtemp");
2263
goto end;
2264
}
2265
tempdir_created = true;
2266
2267
if(quit_now){
2268
goto end;
2269
}
2270
2271
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2272
fprintf_plus(stderr, "init_gpgme failed\n");
2273
exitcode = EX_UNAVAILABLE;
2274
goto end;
2275
} else {
2276
gpgme_initialized = true;
2277
}
2278
2279
if(quit_now){
2280
goto end;
2281
}
2282
2283
if(connect_to != NULL){
2284
/* Connect directly, do not use Zeroconf */
2285
/* (Mainly meant for debugging) */
2286
char *address = strrchr(connect_to, ':');
2287
2288
if(address == NULL){
2289
fprintf_plus(stderr, "No colon in address\n");
2290
exitcode = EX_USAGE;
2291
goto end;
2292
}
2293
2294
if(quit_now){
2295
goto end;
2296
}
2297
2298
in_port_t port;
2299
errno = 0;
2300
tmpmax = strtoimax(address+1, &tmp, 10);
2301
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2302
or tmpmax != (in_port_t)tmpmax){
2303
fprintf_plus(stderr, "Bad port number\n");
2304
exitcode = EX_USAGE;
2305
goto end;
2306
}
2307
2308
if(quit_now){
2309
goto end;
2310
}
2311
2312
port = (in_port_t)tmpmax;
2313
*address = '\0';
2314
/* Colon in address indicates IPv6 */
2315
int af;
2316
if(strchr(connect_to, ':') != NULL){
2317
af = AF_INET6;
2318
/* Accept [] around IPv6 address - see RFC 5952 */
2319
if(connect_to[0] == '[' and address[-1] == ']')
2320
{
2321
connect_to++;
2322
address[-1] = '\0';
2323
}
2324
} else {
2325
af = AF_INET;
2326
}
2327
address = connect_to;
2328
2329
if(quit_now){
2330
goto end;
2331
}
2332
2333
while(not quit_now){
2334
ret = start_mandos_communication(address, port, if_index, af,
2335
&mc);
2336
if(quit_now or ret == 0){
2337
break;
2338
}
2339
if(debug){
2340
fprintf_plus(stderr, "Retrying in %d seconds\n",
2341
(int)retry_interval);
2342
}
2343
sleep((unsigned int)retry_interval);
2344
}
2345
2346
if (not quit_now){
2347
exitcode = EXIT_SUCCESS;
2348
}
2349
2350
goto end;
2351
}
2352
2353
if(quit_now){
2354
goto end;
2355
}
2356
2357
{
2358
AvahiServerConfig config;
2359
/* Do not publish any local Zeroconf records */
2360
avahi_server_config_init(&config);
2361
config.publish_hinfo = 0;
2362
config.publish_addresses = 0;
2363
config.publish_workstation = 0;
2364
config.publish_domain = 0;
2365
2366
/* Allocate a new server */
2367
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2368
&config, NULL, NULL, &ret_errno);
2369
2370
/* Free the Avahi configuration data */
2371
avahi_server_config_free(&config);
2372
}
2373
2374
/* Check if creating the Avahi server object succeeded */
2375
if(mc.server == NULL){
2376
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2377
avahi_strerror(ret_errno));
2378
exitcode = EX_UNAVAILABLE;
2379
goto end;
2380
}
2381
2382
if(quit_now){
2383
goto end;
2384
}
2385
2386
/* Create the Avahi service browser */
2387
sb = avahi_s_service_browser_new(mc.server, if_index,
2388
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2389
NULL, 0, browse_callback,
2390
(void *)&mc);
2391
if(sb == NULL){
2392
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2393
avahi_strerror(avahi_server_errno(mc.server)));
2394
exitcode = EX_UNAVAILABLE;
2395
goto end;
2396
}
2397
2398
if(quit_now){
2399
goto end;
2400
}
2401
2402
/* Run the main loop */
2403
2404
if(debug){
2405
fprintf_plus(stderr, "Starting Avahi loop search\n");
2406
}
2407
2408
ret = avahi_loop_with_timeout(simple_poll,
2409
(int)(retry_interval * 1000), &mc);
2410
if(debug){
2411
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2412
(ret == 0) ? "successfully" : "with error");
2413
}
2414
2415
end:
2416
2417
if(debug){
2418
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2419
}
2420
2421
/* Cleanup things */
2422
free(mc.interfaces);
2423
2424
if(sb != NULL)
2425
avahi_s_service_browser_free(sb);
2426
2427
if(mc.server != NULL)
2428
avahi_server_free(mc.server);
2429
2430
if(simple_poll != NULL)
2431
avahi_simple_poll_free(simple_poll);
2432
2433
if(gnutls_initialized){
2434
gnutls_certificate_free_credentials(mc.cred);
2435
gnutls_global_deinit();
2436
gnutls_dh_params_deinit(mc.dh_params);
2437
}
2438
2439
if(gpgme_initialized){
2440
gpgme_release(mc.ctx);
2441
}
2442
2443
/* Cleans up the circular linked list of Mandos servers the client
2444
has seen */
2445
if(mc.current_server != NULL){
2446
mc.current_server->prev->next = NULL;
2447
while(mc.current_server != NULL){
2448
server *next = mc.current_server->next;
2449
free(mc.current_server);
2450
mc.current_server = next;
2451
}
2452
}
2453
2454
/* Re-raise priviliges */
2455
{
2456
raise_privileges();
2457
2458
/* Run network hooks */
2459
run_network_hooks("stop", interfaces_hooks != NULL ?
2460
interfaces_hooks : "", delay);
2461
2462
/* Take down the network interfaces which were brought up */
2463
{
2464
char *interface = NULL;
2465
while((interface=argz_next(interfaces_to_take_down,
2466
interfaces_to_take_down_size,
2467
interface))){
2468
ret_errno = take_down_interface(interface);
2469
if(ret_errno != 0){
2470
errno = ret_errno;
2471
perror_plus("Failed to take down interface");
2472
}
2473
}
2474
if(debug and (interfaces_to_take_down == NULL)){
2475
fprintf_plus(stderr, "No interfaces needed to be taken"
2476
" down\n");
2477
}
2478
}
2479
2480
lower_privileges_permanently();
2481
}
2482
2483
free(interfaces_to_take_down);
2484
free(interfaces_hooks);
2485
2486
/* Removes the GPGME temp directory and all files inside */
2487
if(tempdir_created){
2488
struct dirent **direntries = NULL;
2489
struct dirent *direntry = NULL;
2490
int numentries = scandir(tempdir, &direntries, notdotentries,
2491
alphasort);
2492
if (numentries > 0){
2493
for(int i = 0; i < numentries; i++){
2494
direntry = direntries[i];
2495
char *fullname = NULL;
2496
ret = asprintf(&fullname, "%s/%s", tempdir,
2497
direntry->d_name);
2498
if(ret < 0){
2499
perror_plus("asprintf");
2500
continue;
2501
}
2502
ret = remove(fullname);
2503
if(ret == -1){
2504
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2505
strerror(errno));
2506
}
2507
free(fullname);
2508
}
2509
}
2510
2511
/* need to clean even if 0 because man page doesn't specify */
2512
free(direntries);
2513
if (numentries == -1){
2514
perror_plus("scandir");
2515
}
2516
ret = rmdir(tempdir);
2517
if(ret == -1 and errno != ENOENT){
2518
perror_plus("rmdir");
2519
}
2520
}
2521
2522
if(quit_now){
2523
sigemptyset(&old_sigterm_action.sa_mask);
2524
old_sigterm_action.sa_handler = SIG_DFL;
2525
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2526
&old_sigterm_action,
2527
NULL));
2528
if(ret == -1){
2529
perror_plus("sigaction");
2530
}
2531
do {
2532
ret = raise(signal_received);
2533
} while(ret != 0 and errno == EINTR);
2534
if(ret != 0){
2535
perror_plus("raise");
2536
abort();
2537
}
2538
TEMP_FAILURE_RETRY(pause());
2539
}
2540
2541
return exitcode;
2542
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0