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- Committer: Teddy Hogeborn
- Date: 2018-02-22 09:20:19 UTC
- mto: (237.7.594 trunk)
- mto: This revision was merged to the branch mainline in revision 366.
- Revision ID: teddy@recompile.se-20180222092019-ehyz79hzti9dnk2g
Client bug fix: Don't use leak sanitizer with leaking libraries
* Makefile (plugin-helpers/mandos-client): Remove "-fsanitize=leak"
from CFLAGS.
* Makefile (plugin-helpers/mandos-client): Remove "-fsanitize=leak"
from CFLAGS.
- files added:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- plugins.d
- files removed:
- bad-ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- files modified:
- Makefile
added
removed
plugins.d/mandos-client.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos-client - get and decrypt data from a Mandos server
4
*
5
* This program is partly derived from an example program for an Avahi
6
* service browser, downloaded from
7
* <http://avahi.org/browser/examples/core-browse-services.c>. This
8
* includes the following functions: "resolve_callback",
9
* "browse_callback", and parts of "main".
10
*
11
* Everything else is
12
* Copyright © 2008-2018 Teddy Hogeborn
13
* Copyright © 2008-2018 Björn Påhlsson
14
*
15
* This file is part of Mandos.
16
*
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
21
*
22
* Mandos is distributed in the hope that it will be useful, but
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25
* General Public License for more details.
26
*
27
* You should have received a copy of the GNU General Public License
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
29
*
30
* Contact the authors at <mandos@recompile.se>.
31
*/
32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
34
#ifndef _LARGEFILE_SOURCE
35
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
37
#ifndef _FILE_OFFSET_BITS
38
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
40
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
44
stdout, ferror() */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
46
#include <stddef.h> /* NULL, size_t, ssize_t */
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
strtof(), abort() */
49
#include <stdbool.h> /* bool, false, true */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
52
*/
53
#include <sys/ioctl.h> /* ioctl */
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
55
sockaddr_in6, PF_INET6,
56
SOCK_STREAM, uid_t, gid_t, open(),
57
opendir(), DIR */
58
#include <sys/stat.h> /* open(), S_ISREG */
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
60
inet_pton(), connect(),
61
getnameinfo() */
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
64
*/
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
66
strtoimax() */
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
68
EAI_SYSTEM, ENETUNREACH,
69
EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
71
ENOTEMPTY,
72
program_invocation_short_name */
73
#include <time.h> /* nanosleep(), time(), sleep() */
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
75
SIOCSIFFLAGS, if_indextoname(),
76
if_nametoindex(), IF_NAMESIZE */
77
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
78
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
79
*/
80
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
81
getuid(), getgid(), seteuid(),
82
setgid(), pause(), _exit(),
83
unlinkat() */
84
#include <arpa/inet.h> /* inet_pton(), htons() */
85
#include <iso646.h> /* not, or, and */
86
#include <argp.h> /* struct argp_option, error_t, struct
87
argp_state, struct argp,
88
argp_parse(), ARGP_KEY_ARG,
89
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
90
#include <signal.h> /* sigemptyset(), sigaddset(),
91
sigaction(), SIGTERM, sig_atomic_t,
92
raise() */
93
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
94
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
95
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
96
WEXITSTATUS(), WTERMSIG() */
97
#include <grp.h> /* setgroups() */
98
#include <argz.h> /* argz_add_sep(), argz_next(),
99
argz_delete(), argz_append(),
100
argz_stringify(), argz_add(),
101
argz_count() */
102
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
103
EAI_SYSTEM, gai_strerror() */
104
105
#ifdef __linux__
106
#include <sys/klog.h> /* klogctl() */
107
#endif /* __linux__ */
108
109
/* Avahi */
110
/* All Avahi types, constants and functions
111
Avahi*, avahi_*,
112
AVAHI_* */
113
#include <avahi-core/core.h>
114
#include <avahi-core/lookup.h>
115
#include <avahi-core/log.h>
116
#include <avahi-common/simple-watch.h>
117
#include <avahi-common/malloc.h>
118
#include <avahi-common/error.h>
119
120
/* GnuTLS */
121
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
122
functions:
123
gnutls_*
124
init_gnutls_session(),
125
GNUTLS_* */
126
#include <gnutls/openpgp.h>
127
/* gnutls_certificate_set_openpgp_key_file(),
128
GNUTLS_OPENPGP_FMT_BASE64 */
129
130
/* GPGME */
131
#include <gpgme.h> /* All GPGME types, constants and
132
functions:
133
gpgme_*
134
GPGME_PROTOCOL_OpenPGP,
135
GPG_ERR_NO_* */
136
137
#define BUFFER_SIZE 256
138
139
#define PATHDIR "/conf/conf.d/mandos"
140
#define SECKEY "seckey.txt"
141
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
143
144
bool debug = false;
145
static const char mandos_protocol_version[] = "1";
146
const char *argp_program_version = "mandos-client " VERSION;
147
const char *argp_program_bug_address = "<mandos@recompile.se>";
148
static const char sys_class_net[] = "/sys/class/net";
149
char *connect_to = NULL;
150
const char *hookdir = HOOKDIR;
151
int hookdir_fd = -1;
152
uid_t uid = 65534;
153
gid_t gid = 65534;
154
155
/* Doubly linked list that need to be circularly linked when used */
156
typedef struct server{
157
const char *ip;
158
in_port_t port;
159
AvahiIfIndex if_index;
160
int af;
161
struct timespec last_seen;
162
struct server *next;
163
struct server *prev;
164
} server;
165
166
/* Used for passing in values through the Avahi callback functions */
167
typedef struct {
168
AvahiServer *server;
169
gnutls_certificate_credentials_t cred;
170
unsigned int dh_bits;
171
gnutls_dh_params_t dh_params;
172
const char *priority;
173
gpgme_ctx_t ctx;
174
server *current_server;
175
char *interfaces;
176
size_t interfaces_size;
177
} mandos_context;
178
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
181
182
sig_atomic_t quit_now = 0;
183
int signal_received = 0;
184
185
/* Function to use when printing errors */
186
void perror_plus(const char *print_text){
187
int e = errno;
188
fprintf(stderr, "Mandos plugin %s: ",
189
program_invocation_short_name);
190
errno = e;
191
perror(print_text);
192
}
193
194
__attribute__((format (gnu_printf, 2, 3), nonnull))
195
int fprintf_plus(FILE *stream, const char *format, ...){
196
va_list ap;
197
va_start (ap, format);
198
199
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
200
program_invocation_short_name));
201
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
202
}
203
204
/*
205
* Make additional room in "buffer" for at least BUFFER_SIZE more
206
* bytes. "buffer_capacity" is how much is currently allocated,
207
* "buffer_length" is how much is already used.
208
*/
209
__attribute__((nonnull, warn_unused_result))
210
size_t incbuffer(char **buffer, size_t buffer_length,
211
size_t buffer_capacity){
212
if(buffer_length + BUFFER_SIZE > buffer_capacity){
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
214
if(new_buf == NULL){
215
int old_errno = errno;
216
free(*buffer);
217
errno = old_errno;
218
*buffer = NULL;
219
return 0;
220
}
221
*buffer = new_buf;
222
buffer_capacity += BUFFER_SIZE;
223
}
224
return buffer_capacity;
225
}
226
227
/* Add server to set of servers to retry periodically */
228
__attribute__((nonnull, warn_unused_result))
229
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
230
int af, server **current_server){
231
int ret;
232
server *new_server = malloc(sizeof(server));
233
if(new_server == NULL){
234
perror_plus("malloc");
235
return false;
236
}
237
*new_server = (server){ .ip = strdup(ip),
238
.port = port,
239
.if_index = if_index,
240
.af = af };
241
if(new_server->ip == NULL){
242
perror_plus("strdup");
243
free(new_server);
244
return false;
245
}
246
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
247
if(ret == -1){
248
perror_plus("clock_gettime");
249
#ifdef __GNUC__
250
#pragma GCC diagnostic push
251
#pragma GCC diagnostic ignored "-Wcast-qual"
252
#endif
253
free((char *)(new_server->ip));
254
#ifdef __GNUC__
255
#pragma GCC diagnostic pop
256
#endif
257
free(new_server);
258
return false;
259
}
260
/* Special case of first server */
261
if(*current_server == NULL){
262
new_server->next = new_server;
263
new_server->prev = new_server;
264
*current_server = new_server;
265
} else {
266
/* Place the new server last in the list */
267
new_server->next = *current_server;
268
new_server->prev = (*current_server)->prev;
269
new_server->prev->next = new_server;
270
(*current_server)->prev = new_server;
271
}
272
return true;
273
}
274
275
/*
276
* Initialize GPGME.
277
*/
278
__attribute__((nonnull, warn_unused_result))
279
static bool init_gpgme(const char * const seckey,
280
const char * const pubkey,
281
const char * const tempdir,
282
mandos_context *mc){
283
gpgme_error_t rc;
284
gpgme_engine_info_t engine_info;
285
286
/*
287
* Helper function to insert pub and seckey to the engine keyring.
288
*/
289
bool import_key(const char * const filename){
290
int ret;
291
int fd;
292
gpgme_data_t pgp_data;
293
294
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
295
if(fd == -1){
296
perror_plus("open");
297
return false;
298
}
299
300
rc = gpgme_data_new_from_fd(&pgp_data, fd);
301
if(rc != GPG_ERR_NO_ERROR){
302
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
303
gpgme_strsource(rc), gpgme_strerror(rc));
304
return false;
305
}
306
307
rc = gpgme_op_import(mc->ctx, pgp_data);
308
if(rc != GPG_ERR_NO_ERROR){
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
311
return false;
312
}
313
314
ret = close(fd);
315
if(ret == -1){
316
perror_plus("close");
317
}
318
gpgme_data_release(pgp_data);
319
return true;
320
}
321
322
if(debug){
323
fprintf_plus(stderr, "Initializing GPGME\n");
324
}
325
326
/* Init GPGME */
327
gpgme_check_version(NULL);
328
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
329
if(rc != GPG_ERR_NO_ERROR){
330
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
331
gpgme_strsource(rc), gpgme_strerror(rc));
332
return false;
333
}
334
335
/* Set GPGME home directory for the OpenPGP engine only */
336
rc = gpgme_get_engine_info(&engine_info);
337
if(rc != GPG_ERR_NO_ERROR){
338
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
339
gpgme_strsource(rc), gpgme_strerror(rc));
340
return false;
341
}
342
while(engine_info != NULL){
343
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
344
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
345
engine_info->file_name, tempdir);
346
break;
347
}
348
engine_info = engine_info->next;
349
}
350
if(engine_info == NULL){
351
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
352
tempdir);
353
return false;
354
}
355
356
/* Create new GPGME "context" */
357
rc = gpgme_new(&(mc->ctx));
358
if(rc != GPG_ERR_NO_ERROR){
359
fprintf_plus(stderr, "Mandos plugin mandos-client: "
360
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
361
gpgme_strerror(rc));
362
return false;
363
}
364
365
if(not import_key(pubkey) or not import_key(seckey)){
366
return false;
367
}
368
369
return true;
370
}
371
372
/*
373
* Decrypt OpenPGP data.
374
* Returns -1 on error
375
*/
376
__attribute__((nonnull, warn_unused_result))
377
static ssize_t pgp_packet_decrypt(const char *cryptotext,
378
size_t crypto_size,
379
char **plaintext,
380
mandos_context *mc){
381
gpgme_data_t dh_crypto, dh_plain;
382
gpgme_error_t rc;
383
ssize_t ret;
384
size_t plaintext_capacity = 0;
385
ssize_t plaintext_length = 0;
386
387
if(debug){
388
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
389
}
390
391
/* Create new GPGME data buffer from memory cryptotext */
392
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
393
0);
394
if(rc != GPG_ERR_NO_ERROR){
395
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
396
gpgme_strsource(rc), gpgme_strerror(rc));
397
return -1;
398
}
399
400
/* Create new empty GPGME data buffer for the plaintext */
401
rc = gpgme_data_new(&dh_plain);
402
if(rc != GPG_ERR_NO_ERROR){
403
fprintf_plus(stderr, "Mandos plugin mandos-client: "
404
"bad gpgme_data_new: %s: %s\n",
405
gpgme_strsource(rc), gpgme_strerror(rc));
406
gpgme_data_release(dh_crypto);
407
return -1;
408
}
409
410
/* Decrypt data from the cryptotext data buffer to the plaintext
411
data buffer */
412
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
413
if(rc != GPG_ERR_NO_ERROR){
414
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
415
gpgme_strsource(rc), gpgme_strerror(rc));
416
plaintext_length = -1;
417
if(debug){
418
gpgme_decrypt_result_t result;
419
result = gpgme_op_decrypt_result(mc->ctx);
420
if(result == NULL){
421
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
422
} else {
423
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
424
result->unsupported_algorithm);
425
fprintf_plus(stderr, "Wrong key usage: %u\n",
426
result->wrong_key_usage);
427
if(result->file_name != NULL){
428
fprintf_plus(stderr, "File name: %s\n", result->file_name);
429
}
430
gpgme_recipient_t recipient;
431
recipient = result->recipients;
432
while(recipient != NULL){
433
fprintf_plus(stderr, "Public key algorithm: %s\n",
434
gpgme_pubkey_algo_name
435
(recipient->pubkey_algo));
436
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
437
fprintf_plus(stderr, "Secret key available: %s\n",
438
recipient->status == GPG_ERR_NO_SECKEY
439
? "No" : "Yes");
440
recipient = recipient->next;
441
}
442
}
443
}
444
goto decrypt_end;
445
}
446
447
if(debug){
448
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
449
}
450
451
/* Seek back to the beginning of the GPGME plaintext data buffer */
452
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
453
perror_plus("gpgme_data_seek");
454
plaintext_length = -1;
455
goto decrypt_end;
456
}
457
458
*plaintext = NULL;
459
while(true){
460
plaintext_capacity = incbuffer(plaintext,
461
(size_t)plaintext_length,
462
plaintext_capacity);
463
if(plaintext_capacity == 0){
464
perror_plus("incbuffer");
465
plaintext_length = -1;
466
goto decrypt_end;
467
}
468
469
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
470
BUFFER_SIZE);
471
/* Print the data, if any */
472
if(ret == 0){
473
/* EOF */
474
break;
475
}
476
if(ret < 0){
477
perror_plus("gpgme_data_read");
478
plaintext_length = -1;
479
goto decrypt_end;
480
}
481
plaintext_length += ret;
482
}
483
484
if(debug){
485
fprintf_plus(stderr, "Decrypted password is: ");
486
for(ssize_t i = 0; i < plaintext_length; i++){
487
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
488
}
489
fprintf(stderr, "\n");
490
}
491
492
decrypt_end:
493
494
/* Delete the GPGME cryptotext data buffer */
495
gpgme_data_release(dh_crypto);
496
497
/* Delete the GPGME plaintext data buffer */
498
gpgme_data_release(dh_plain);
499
return plaintext_length;
500
}
501
502
__attribute__((warn_unused_result, const))
503
static const char *safe_string(const char *str){
504
if(str == NULL)
505
return "(unknown)";
506
return str;
507
}
508
509
__attribute__((warn_unused_result))
510
static const char *safer_gnutls_strerror(int value){
511
const char *ret = gnutls_strerror(value);
512
return safe_string(ret);
513
}
514
515
/* GnuTLS log function callback */
516
__attribute__((nonnull))
517
static void debuggnutls(__attribute__((unused)) int level,
518
const char* string){
519
fprintf_plus(stderr, "GnuTLS: %s", string);
520
}
521
522
__attribute__((nonnull(1, 2, 4), warn_unused_result))
523
static int init_gnutls_global(const char *pubkeyfilename,
524
const char *seckeyfilename,
525
const char *dhparamsfilename,
526
mandos_context *mc){
527
int ret;
528
unsigned int uret;
529
530
if(debug){
531
fprintf_plus(stderr, "Initializing GnuTLS\n");
532
}
533
534
if(debug){
535
/* "Use a log level over 10 to enable all debugging options."
536
* - GnuTLS manual
537
*/
538
gnutls_global_set_log_level(11);
539
gnutls_global_set_log_function(debuggnutls);
540
}
541
542
/* OpenPGP credentials */
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
544
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
546
safer_gnutls_strerror(ret));
547
return -1;
548
}
549
550
if(debug){
551
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
552
" secret key %s as GnuTLS credentials\n",
553
pubkeyfilename,
554
seckeyfilename);
555
}
556
557
ret = gnutls_certificate_set_openpgp_key_file
558
(mc->cred, pubkeyfilename, seckeyfilename,
559
GNUTLS_OPENPGP_FMT_BASE64);
560
if(ret != GNUTLS_E_SUCCESS){
561
fprintf_plus(stderr,
562
"Error[%d] while reading the OpenPGP key pair ('%s',"
563
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
564
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
565
safer_gnutls_strerror(ret));
566
goto globalfail;
567
}
568
569
/* GnuTLS server initialization */
570
ret = gnutls_dh_params_init(&mc->dh_params);
571
if(ret != GNUTLS_E_SUCCESS){
572
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
573
" initialization: %s\n",
574
safer_gnutls_strerror(ret));
575
goto globalfail;
576
}
577
/* If a Diffie-Hellman parameters file was given, try to use it */
578
if(dhparamsfilename != NULL){
579
gnutls_datum_t params = { .data = NULL, .size = 0 };
580
do {
581
int dhpfile = open(dhparamsfilename, O_RDONLY);
582
if(dhpfile == -1){
583
perror_plus("open");
584
dhparamsfilename = NULL;
585
break;
586
}
587
size_t params_capacity = 0;
588
while(true){
589
params_capacity = incbuffer((char **)¶ms.data,
590
(size_t)params.size,
591
(size_t)params_capacity);
592
if(params_capacity == 0){
593
perror_plus("incbuffer");
594
free(params.data);
595
params.data = NULL;
596
dhparamsfilename = NULL;
597
break;
598
}
599
ssize_t bytes_read = read(dhpfile,
600
params.data + params.size,
601
BUFFER_SIZE);
602
/* EOF */
603
if(bytes_read == 0){
604
break;
605
}
606
/* check bytes_read for failure */
607
if(bytes_read < 0){
608
perror_plus("read");
609
free(params.data);
610
params.data = NULL;
611
dhparamsfilename = NULL;
612
break;
613
}
614
params.size += (unsigned int)bytes_read;
615
}
616
close(dhpfile);
617
if(params.data == NULL){
618
dhparamsfilename = NULL;
619
}
620
if(dhparamsfilename == NULL){
621
break;
622
}
623
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
624
GNUTLS_X509_FMT_PEM);
625
if(ret != GNUTLS_E_SUCCESS){
626
fprintf_plus(stderr, "Failed to parse DH parameters in file"
627
" \"%s\": %s\n", dhparamsfilename,
628
safer_gnutls_strerror(ret));
629
dhparamsfilename = NULL;
630
}
631
free(params.data);
632
} while(false);
633
}
634
if(dhparamsfilename == NULL){
635
if(mc->dh_bits == 0){
636
/* Find out the optimal number of DH bits */
637
/* Try to read the private key file */
638
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
639
do {
640
int secfile = open(seckeyfilename, O_RDONLY);
641
if(secfile == -1){
642
perror_plus("open");
643
break;
644
}
645
size_t buffer_capacity = 0;
646
while(true){
647
buffer_capacity = incbuffer((char **)&buffer.data,
648
(size_t)buffer.size,
649
(size_t)buffer_capacity);
650
if(buffer_capacity == 0){
651
perror_plus("incbuffer");
652
free(buffer.data);
653
buffer.data = NULL;
654
break;
655
}
656
ssize_t bytes_read = read(secfile,
657
buffer.data + buffer.size,
658
BUFFER_SIZE);
659
/* EOF */
660
if(bytes_read == 0){
661
break;
662
}
663
/* check bytes_read for failure */
664
if(bytes_read < 0){
665
perror_plus("read");
666
free(buffer.data);
667
buffer.data = NULL;
668
break;
669
}
670
buffer.size += (unsigned int)bytes_read;
671
}
672
close(secfile);
673
} while(false);
674
/* If successful, use buffer to parse private key */
675
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
676
if(buffer.data != NULL){
677
{
678
gnutls_openpgp_privkey_t privkey = NULL;
679
ret = gnutls_openpgp_privkey_init(&privkey);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error initializing OpenPGP key"
682
" structure: %s",
683
safer_gnutls_strerror(ret));
684
free(buffer.data);
685
buffer.data = NULL;
686
} else {
687
ret = gnutls_openpgp_privkey_import
688
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
689
if(ret != GNUTLS_E_SUCCESS){
690
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
691
safer_gnutls_strerror(ret));
692
privkey = NULL;
693
}
694
free(buffer.data);
695
buffer.data = NULL;
696
if(privkey != NULL){
697
/* Use private key to suggest an appropriate
698
sec_param */
699
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
700
gnutls_openpgp_privkey_deinit(privkey);
701
if(debug){
702
fprintf_plus(stderr, "This OpenPGP key implies using"
703
" a GnuTLS security parameter \"%s\".\n",
704
safe_string(gnutls_sec_param_get_name
705
(sec_param)));
706
}
707
}
708
}
709
}
710
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
711
/* Err on the side of caution */
712
sec_param = GNUTLS_SEC_PARAM_ULTRA;
713
if(debug){
714
fprintf_plus(stderr, "Falling back to security parameter"
715
" \"%s\"\n",
716
safe_string(gnutls_sec_param_get_name
717
(sec_param)));
718
}
719
}
720
}
721
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
722
if(uret != 0){
723
mc->dh_bits = uret;
724
if(debug){
725
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
726
" implies %u DH bits; using that.\n",
727
safe_string(gnutls_sec_param_get_name
728
(sec_param)),
729
mc->dh_bits);
730
}
731
} else {
732
fprintf_plus(stderr, "Failed to get implied number of DH"
733
" bits for security parameter \"%s\"): %s\n",
734
safe_string(gnutls_sec_param_get_name
735
(sec_param)),
736
safer_gnutls_strerror(ret));
737
goto globalfail;
738
}
739
} else if(debug){
740
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
741
mc->dh_bits);
742
}
743
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
744
if(ret != GNUTLS_E_SUCCESS){
745
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
746
" bits): %s\n", mc->dh_bits,
747
safer_gnutls_strerror(ret));
748
goto globalfail;
749
}
750
}
751
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
752
753
return 0;
754
755
globalfail:
756
757
gnutls_certificate_free_credentials(mc->cred);
758
gnutls_dh_params_deinit(mc->dh_params);
759
return -1;
760
}
761
762
__attribute__((nonnull, warn_unused_result))
763
static int init_gnutls_session(gnutls_session_t *session,
764
mandos_context *mc){
765
int ret;
766
/* GnuTLS session creation */
767
do {
768
ret = gnutls_init(session, GNUTLS_SERVER);
769
if(quit_now){
770
return -1;
771
}
772
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
773
if(ret != GNUTLS_E_SUCCESS){
774
fprintf_plus(stderr,
775
"Error in GnuTLS session initialization: %s\n",
776
safer_gnutls_strerror(ret));
777
}
778
779
{
780
const char *err;
781
do {
782
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
783
if(quit_now){
784
gnutls_deinit(*session);
785
return -1;
786
}
787
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
788
if(ret != GNUTLS_E_SUCCESS){
789
fprintf_plus(stderr, "Syntax error at: %s\n", err);
790
fprintf_plus(stderr, "GnuTLS error: %s\n",
791
safer_gnutls_strerror(ret));
792
gnutls_deinit(*session);
793
return -1;
794
}
795
}
796
797
do {
798
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
799
mc->cred);
800
if(quit_now){
801
gnutls_deinit(*session);
802
return -1;
803
}
804
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
805
if(ret != GNUTLS_E_SUCCESS){
806
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
807
safer_gnutls_strerror(ret));
808
gnutls_deinit(*session);
809
return -1;
810
}
811
812
/* ignore client certificate if any. */
813
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
814
815
return 0;
816
}
817
818
/* Avahi log function callback */
819
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
820
__attribute__((unused)) const char *txt){}
821
822
/* Set effective uid to 0, return errno */
823
__attribute__((warn_unused_result))
824
int raise_privileges(void){
825
int old_errno = errno;
826
int ret = 0;
827
if(seteuid(0) == -1){
828
ret = errno;
829
}
830
errno = old_errno;
831
return ret;
832
}
833
834
/* Set effective and real user ID to 0. Return errno. */
835
__attribute__((warn_unused_result))
836
int raise_privileges_permanently(void){
837
int old_errno = errno;
838
int ret = raise_privileges();
839
if(ret != 0){
840
errno = old_errno;
841
return ret;
842
}
843
if(setuid(0) == -1){
844
ret = errno;
845
}
846
errno = old_errno;
847
return ret;
848
}
849
850
/* Set effective user ID to unprivileged saved user ID */
851
__attribute__((warn_unused_result))
852
int lower_privileges(void){
853
int old_errno = errno;
854
int ret = 0;
855
if(seteuid(uid) == -1){
856
ret = errno;
857
}
858
errno = old_errno;
859
return ret;
860
}
861
862
/* Lower privileges permanently */
863
__attribute__((warn_unused_result))
864
int lower_privileges_permanently(void){
865
int old_errno = errno;
866
int ret = 0;
867
if(setuid(uid) == -1){
868
ret = errno;
869
}
870
errno = old_errno;
871
return ret;
872
}
873
874
/* Helper function to add_local_route() and delete_local_route() */
875
__attribute__((nonnull, warn_unused_result))
876
static bool add_delete_local_route(const bool add,
877
const char *address,
878
AvahiIfIndex if_index){
879
int ret;
880
char helper[] = "mandos-client-iprouteadddel";
881
char add_arg[] = "add";
882
char delete_arg[] = "delete";
883
char debug_flag[] = "--debug";
884
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
885
if(pluginhelperdir == NULL){
886
if(debug){
887
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
888
" variable not set; cannot run helper\n");
889
}
890
return false;
891
}
892
893
char interface[IF_NAMESIZE];
894
if(if_indextoname((unsigned int)if_index, interface) == NULL){
895
perror_plus("if_indextoname");
896
return false;
897
}
898
899
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
900
if(devnull == -1){
901
perror_plus("open(\"/dev/null\", O_RDONLY)");
902
return false;
903
}
904
pid_t pid = fork();
905
if(pid == 0){
906
/* Child */
907
/* Raise privileges */
908
errno = raise_privileges_permanently();
909
if(errno != 0){
910
perror_plus("Failed to raise privileges");
911
/* _exit(EX_NOPERM); */
912
} else {
913
/* Set group */
914
errno = 0;
915
ret = setgid(0);
916
if(ret == -1){
917
perror_plus("setgid");
918
_exit(EX_NOPERM);
919
}
920
/* Reset supplementary groups */
921
errno = 0;
922
ret = setgroups(0, NULL);
923
if(ret == -1){
924
perror_plus("setgroups");
925
_exit(EX_NOPERM);
926
}
927
}
928
ret = dup2(devnull, STDIN_FILENO);
929
if(ret == -1){
930
perror_plus("dup2(devnull, STDIN_FILENO)");
931
_exit(EX_OSERR);
932
}
933
ret = close(devnull);
934
if(ret == -1){
935
perror_plus("close");
936
_exit(EX_OSERR);
937
}
938
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
939
if(ret == -1){
940
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
941
_exit(EX_OSERR);
942
}
943
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
944
O_RDONLY
945
| O_DIRECTORY
946
| O_PATH
947
| O_CLOEXEC));
948
if(helperdir_fd == -1){
949
perror_plus("open");
950
_exit(EX_UNAVAILABLE);
951
}
952
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
953
helper, O_RDONLY));
954
if(helper_fd == -1){
955
perror_plus("openat");
956
close(helperdir_fd);
957
_exit(EX_UNAVAILABLE);
958
}
959
close(helperdir_fd);
960
#ifdef __GNUC__
961
#pragma GCC diagnostic push
962
#pragma GCC diagnostic ignored "-Wcast-qual"
963
#endif
964
if(fexecve(helper_fd, (char *const [])
965
{ helper, add ? add_arg : delete_arg, (char *)address,
966
interface, debug ? debug_flag : NULL, NULL },
967
environ) == -1){
968
#ifdef __GNUC__
969
#pragma GCC diagnostic pop
970
#endif
971
perror_plus("fexecve");
972
_exit(EXIT_FAILURE);
973
}
974
}
975
if(pid == -1){
976
perror_plus("fork");
977
return false;
978
}
979
int status;
980
pid_t pret = -1;
981
errno = 0;
982
do {
983
pret = waitpid(pid, &status, 0);
984
if(pret == -1 and errno == EINTR and quit_now){
985
int errno_raising = 0;
986
if((errno = raise_privileges()) != 0){
987
errno_raising = errno;
988
perror_plus("Failed to raise privileges in order to"
989
" kill helper program");
990
}
991
if(kill(pid, SIGTERM) == -1){
992
perror_plus("kill");
993
}
994
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
995
perror_plus("Failed to lower privileges after killing"
996
" helper program");
997
}
998
return false;
999
}
1000
} while(pret == -1 and errno == EINTR);
1001
if(pret == -1){
1002
perror_plus("waitpid");
1003
return false;
1004
}
1005
if(WIFEXITED(status)){
1006
if(WEXITSTATUS(status) != 0){
1007
fprintf_plus(stderr, "Error: iprouteadddel exited"
1008
" with status %d\n", WEXITSTATUS(status));
1009
return false;
1010
}
1011
return true;
1012
}
1013
if(WIFSIGNALED(status)){
1014
fprintf_plus(stderr, "Error: iprouteadddel died by"
1015
" signal %d\n", WTERMSIG(status));
1016
return false;
1017
}
1018
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1019
return false;
1020
}
1021
1022
__attribute__((nonnull, warn_unused_result))
1023
static bool add_local_route(const char *address,
1024
AvahiIfIndex if_index){
1025
if(debug){
1026
fprintf_plus(stderr, "Adding route to %s\n", address);
1027
}
1028
return add_delete_local_route(true, address, if_index);
1029
}
1030
1031
__attribute__((nonnull, warn_unused_result))
1032
static bool delete_local_route(const char *address,
1033
AvahiIfIndex if_index){
1034
if(debug){
1035
fprintf_plus(stderr, "Removing route to %s\n", address);
1036
}
1037
return add_delete_local_route(false, address, if_index);
1038
}
1039
1040
/* Called when a Mandos server is found */
1041
__attribute__((nonnull, warn_unused_result))
1042
static int start_mandos_communication(const char *ip, in_port_t port,
1043
AvahiIfIndex if_index,
1044
int af, mandos_context *mc){
1045
int ret, tcp_sd = -1;
1046
ssize_t sret;
1047
struct sockaddr_storage to;
1048
char *buffer = NULL;
1049
char *decrypted_buffer = NULL;
1050
size_t buffer_length = 0;
1051
size_t buffer_capacity = 0;
1052
size_t written;
1053
int retval = -1;
1054
gnutls_session_t session;
1055
int pf; /* Protocol family */
1056
bool route_added = false;
1057
1058
errno = 0;
1059
1060
if(quit_now){
1061
errno = EINTR;
1062
return -1;
1063
}
1064
1065
switch(af){
1066
case AF_INET6:
1067
pf = PF_INET6;
1068
break;
1069
case AF_INET:
1070
pf = PF_INET;
1071
break;
1072
default:
1073
fprintf_plus(stderr, "Bad address family: %d\n", af);
1074
errno = EINVAL;
1075
return -1;
1076
}
1077
1078
/* If the interface is specified and we have a list of interfaces */
1079
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1080
/* Check if the interface is one of the interfaces we are using */
1081
bool match = false;
1082
{
1083
char *interface = NULL;
1084
while((interface = argz_next(mc->interfaces,
1085
mc->interfaces_size,
1086
interface))){
1087
if(if_nametoindex(interface) == (unsigned int)if_index){
1088
match = true;
1089
break;
1090
}
1091
}
1092
}
1093
if(not match){
1094
/* This interface does not match any in the list, so we don't
1095
connect to the server */
1096
if(debug){
1097
char interface[IF_NAMESIZE];
1098
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1099
perror_plus("if_indextoname");
1100
} else {
1101
fprintf_plus(stderr, "Skipping server on non-used interface"
1102
" \"%s\"\n",
1103
if_indextoname((unsigned int)if_index,
1104
interface));
1105
}
1106
}
1107
return -1;
1108
}
1109
}
1110
1111
ret = init_gnutls_session(&session, mc);
1112
if(ret != 0){
1113
return -1;
1114
}
1115
1116
if(debug){
1117
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1118
PRIuMAX "\n", ip, (uintmax_t)port);
1119
}
1120
1121
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1122
if(tcp_sd < 0){
1123
int e = errno;
1124
perror_plus("socket");
1125
errno = e;
1126
goto mandos_end;
1127
}
1128
1129
if(quit_now){
1130
errno = EINTR;
1131
goto mandos_end;
1132
}
1133
1134
if(af == AF_INET6){
1135
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1136
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1137
ret = inet_pton(af, ip, &to6->sin6_addr);
1138
} else { /* IPv4 */
1139
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1140
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1141
ret = inet_pton(af, ip, &to4->sin_addr);
1142
}
1143
if(ret < 0 ){
1144
int e = errno;
1145
perror_plus("inet_pton");
1146
errno = e;
1147
goto mandos_end;
1148
}
1149
if(ret == 0){
1150
int e = errno;
1151
fprintf_plus(stderr, "Bad address: %s\n", ip);
1152
errno = e;
1153
goto mandos_end;
1154
}
1155
if(af == AF_INET6){
1156
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1157
if(IN6_IS_ADDR_LINKLOCAL
1158
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1159
if(if_index == AVAHI_IF_UNSPEC){
1160
fprintf_plus(stderr, "An IPv6 link-local address is"
1161
" incomplete without a network interface\n");
1162
errno = EINVAL;
1163
goto mandos_end;
1164
}
1165
/* Set the network interface number as scope */
1166
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1167
}
1168
} else {
1169
((struct sockaddr_in *)&to)->sin_port = htons(port);
1170
}
1171
1172
if(quit_now){
1173
errno = EINTR;
1174
goto mandos_end;
1175
}
1176
1177
if(debug){
1178
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1179
char interface[IF_NAMESIZE];
1180
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1181
perror_plus("if_indextoname");
1182
} else {
1183
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1184
"\n", ip, interface, (uintmax_t)port);
1185
}
1186
} else {
1187
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1188
ip, (uintmax_t)port);
1189
}
1190
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1191
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1192
if(af == AF_INET6){
1193
ret = getnameinfo((struct sockaddr *)&to,
1194
sizeof(struct sockaddr_in6),
1195
addrstr, sizeof(addrstr), NULL, 0,
1196
NI_NUMERICHOST);
1197
} else {
1198
ret = getnameinfo((struct sockaddr *)&to,
1199
sizeof(struct sockaddr_in),
1200
addrstr, sizeof(addrstr), NULL, 0,
1201
NI_NUMERICHOST);
1202
}
1203
if(ret == EAI_SYSTEM){
1204
perror_plus("getnameinfo");
1205
} else if(ret != 0) {
1206
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1207
} else if(strcmp(addrstr, ip) != 0){
1208
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1209
}
1210
}
1211
1212
if(quit_now){
1213
errno = EINTR;
1214
goto mandos_end;
1215
}
1216
1217
while(true){
1218
if(af == AF_INET6){
1219
ret = connect(tcp_sd, (struct sockaddr *)&to,
1220
sizeof(struct sockaddr_in6));
1221
} else {
1222
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1223
sizeof(struct sockaddr_in));
1224
}
1225
if(ret < 0){
1226
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1227
and if_index != AVAHI_IF_UNSPEC
1228
and connect_to == NULL
1229
and not route_added and
1230
((af == AF_INET6 and not
1231
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1232
&to)->sin6_addr)))
1233
or (af == AF_INET and
1234
/* Not a a IPv4LL address */
1235
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1236
& 0xFFFF0000L) != 0xA9FE0000L))){
1237
/* Work around Avahi bug - Avahi does not announce link-local
1238
addresses if it has a global address, so local hosts with
1239
*only* a link-local address (e.g. Mandos clients) cannot
1240
connect to a Mandos server announced by Avahi on a server
1241
host with a global address. Work around this by retrying
1242
with an explicit route added with the server's address.
1243
1244
Avahi bug reference:
1245
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1246
https://bugs.debian.org/587961
1247
*/
1248
if(debug){
1249
fprintf_plus(stderr, "Mandos server unreachable, trying"
1250
" direct route\n");
1251
}
1252
int e = errno;
1253
route_added = add_local_route(ip, if_index);
1254
if(route_added){
1255
continue;
1256
}
1257
errno = e;
1258
}
1259
if(errno != ECONNREFUSED or debug){
1260
int e = errno;
1261
perror_plus("connect");
1262
errno = e;
1263
}
1264
goto mandos_end;
1265
}
1266
1267
if(quit_now){
1268
errno = EINTR;
1269
goto mandos_end;
1270
}
1271
break;
1272
}
1273
1274
const char *out = mandos_protocol_version;
1275
written = 0;
1276
while(true){
1277
size_t out_size = strlen(out);
1278
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1279
out_size - written));
1280
if(ret == -1){
1281
int e = errno;
1282
perror_plus("write");
1283
errno = e;
1284
goto mandos_end;
1285
}
1286
written += (size_t)ret;
1287
if(written < out_size){
1288
continue;
1289
} else {
1290
if(out == mandos_protocol_version){
1291
written = 0;
1292
out = "\r\n";
1293
} else {
1294
break;
1295
}
1296
}
1297
1298
if(quit_now){
1299
errno = EINTR;
1300
goto mandos_end;
1301
}
1302
}
1303
1304
if(debug){
1305
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1306
}
1307
1308
if(quit_now){
1309
errno = EINTR;
1310
goto mandos_end;
1311
}
1312
1313
/* This casting via intptr_t is to eliminate warning about casting
1314
an int to a pointer type. This is exactly how the GnuTLS Guile
1315
function "set-session-transport-fd!" does it. */
1316
gnutls_transport_set_ptr(session,
1317
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1318
1319
if(quit_now){
1320
errno = EINTR;
1321
goto mandos_end;
1322
}
1323
1324
do {
1325
ret = gnutls_handshake(session);
1326
if(quit_now){
1327
errno = EINTR;
1328
goto mandos_end;
1329
}
1330
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1331
1332
if(ret != GNUTLS_E_SUCCESS){
1333
if(debug){
1334
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
1335
gnutls_perror(ret);
1336
}
1337
errno = EPROTO;
1338
goto mandos_end;
1339
}
1340
1341
/* Read OpenPGP packet that contains the wanted password */
1342
1343
if(debug){
1344
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1345
" %s\n", ip);
1346
}
1347
1348
while(true){
1349
1350
if(quit_now){
1351
errno = EINTR;
1352
goto mandos_end;
1353
}
1354
1355
buffer_capacity = incbuffer(&buffer, buffer_length,
1356
buffer_capacity);
1357
if(buffer_capacity == 0){
1358
int e = errno;
1359
perror_plus("incbuffer");
1360
errno = e;
1361
goto mandos_end;
1362
}
1363
1364
if(quit_now){
1365
errno = EINTR;
1366
goto mandos_end;
1367
}
1368
1369
sret = gnutls_record_recv(session, buffer+buffer_length,
1370
BUFFER_SIZE);
1371
if(sret == 0){
1372
break;
1373
}
1374
if(sret < 0){
1375
switch(sret){
1376
case GNUTLS_E_INTERRUPTED:
1377
case GNUTLS_E_AGAIN:
1378
break;
1379
case GNUTLS_E_REHANDSHAKE:
1380
do {
1381
ret = gnutls_handshake(session);
1382
1383
if(quit_now){
1384
errno = EINTR;
1385
goto mandos_end;
1386
}
1387
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1388
if(ret < 0){
1389
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1390
"***\n");
1391
gnutls_perror(ret);
1392
errno = EPROTO;
1393
goto mandos_end;
1394
}
1395
break;
1396
default:
1397
fprintf_plus(stderr, "Unknown error while reading data from"
1398
" encrypted session with Mandos server\n");
1399
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1400
errno = EIO;
1401
goto mandos_end;
1402
}
1403
} else {
1404
buffer_length += (size_t) sret;
1405
}
1406
}
1407
1408
if(debug){
1409
fprintf_plus(stderr, "Closing TLS session\n");
1410
}
1411
1412
if(quit_now){
1413
errno = EINTR;
1414
goto mandos_end;
1415
}
1416
1417
do {
1418
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1419
if(quit_now){
1420
errno = EINTR;
1421
goto mandos_end;
1422
}
1423
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1424
1425
if(buffer_length > 0){
1426
ssize_t decrypted_buffer_size;
1427
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1428
&decrypted_buffer, mc);
1429
if(decrypted_buffer_size >= 0){
1430
1431
clearerr(stdout);
1432
written = 0;
1433
while(written < (size_t) decrypted_buffer_size){
1434
if(quit_now){
1435
errno = EINTR;
1436
goto mandos_end;
1437
}
1438
1439
ret = (int)fwrite(decrypted_buffer + written, 1,
1440
(size_t)decrypted_buffer_size - written,
1441
stdout);
1442
if(ret == 0 and ferror(stdout)){
1443
int e = errno;
1444
if(debug){
1445
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1446
strerror(errno));
1447
}
1448
errno = e;
1449
goto mandos_end;
1450
}
1451
written += (size_t)ret;
1452
}
1453
ret = fflush(stdout);
1454
if(ret != 0){
1455
int e = errno;
1456
if(debug){
1457
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1458
strerror(errno));
1459
}
1460
errno = e;
1461
goto mandos_end;
1462
}
1463
retval = 0;
1464
}
1465
}
1466
1467
/* Shutdown procedure */
1468
1469
mandos_end:
1470
{
1471
if(route_added){
1472
if(not delete_local_route(ip, if_index)){
1473
fprintf_plus(stderr, "Failed to delete local route to %s on"
1474
" interface %d", ip, if_index);
1475
}
1476
}
1477
int e = errno;
1478
free(decrypted_buffer);
1479
free(buffer);
1480
if(tcp_sd >= 0){
1481
ret = close(tcp_sd);
1482
}
1483
if(ret == -1){
1484
if(e == 0){
1485
e = errno;
1486
}
1487
perror_plus("close");
1488
}
1489
gnutls_deinit(session);
1490
errno = e;
1491
if(quit_now){
1492
errno = EINTR;
1493
retval = -1;
1494
}
1495
}
1496
return retval;
1497
}
1498
1499
static void resolve_callback(AvahiSServiceResolver *r,
1500
AvahiIfIndex interface,
1501
AvahiProtocol proto,
1502
AvahiResolverEvent event,
1503
const char *name,
1504
const char *type,
1505
const char *domain,
1506
const char *host_name,
1507
const AvahiAddress *address,
1508
uint16_t port,
1509
AVAHI_GCC_UNUSED AvahiStringList *txt,
1510
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1511
flags,
1512
void *mc){
1513
if(r == NULL){
1514
return;
1515
}
1516
1517
/* Called whenever a service has been resolved successfully or
1518
timed out */
1519
1520
if(quit_now){
1521
avahi_s_service_resolver_free(r);
1522
return;
1523
}
1524
1525
switch(event){
1526
default:
1527
case AVAHI_RESOLVER_FAILURE:
1528
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1529
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1530
domain,
1531
avahi_strerror(avahi_server_errno
1532
(((mandos_context*)mc)->server)));
1533
break;
1534
1535
case AVAHI_RESOLVER_FOUND:
1536
{
1537
char ip[AVAHI_ADDRESS_STR_MAX];
1538
avahi_address_snprint(ip, sizeof(ip), address);
1539
if(debug){
1540
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1541
PRIdMAX ") on port %" PRIu16 "\n", name,
1542
host_name, ip, (intmax_t)interface, port);
1543
}
1544
int ret = start_mandos_communication(ip, (in_port_t)port,
1545
interface,
1546
avahi_proto_to_af(proto),
1547
mc);
1548
if(ret == 0){
1549
avahi_simple_poll_quit(simple_poll);
1550
} else {
1551
if(not add_server(ip, (in_port_t)port, interface,
1552
avahi_proto_to_af(proto),
1553
&((mandos_context*)mc)->current_server)){
1554
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1555
" list\n", name);
1556
}
1557
}
1558
}
1559
}
1560
avahi_s_service_resolver_free(r);
1561
}
1562
1563
static void browse_callback(AvahiSServiceBrowser *b,
1564
AvahiIfIndex interface,
1565
AvahiProtocol protocol,
1566
AvahiBrowserEvent event,
1567
const char *name,
1568
const char *type,
1569
const char *domain,
1570
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1571
flags,
1572
void *mc){
1573
if(b == NULL){
1574
return;
1575
}
1576
1577
/* Called whenever a new services becomes available on the LAN or
1578
is removed from the LAN */
1579
1580
if(quit_now){
1581
return;
1582
}
1583
1584
switch(event){
1585
default:
1586
case AVAHI_BROWSER_FAILURE:
1587
1588
fprintf_plus(stderr, "(Avahi browser) %s\n",
1589
avahi_strerror(avahi_server_errno
1590
(((mandos_context*)mc)->server)));
1591
avahi_simple_poll_quit(simple_poll);
1592
return;
1593
1594
case AVAHI_BROWSER_NEW:
1595
/* We ignore the returned Avahi resolver object. In the callback
1596
function we free it. If the Avahi server is terminated before
1597
the callback function is called the Avahi server will free the
1598
resolver for us. */
1599
1600
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1601
interface, protocol, name, type,
1602
domain, protocol, 0,
1603
resolve_callback, mc) == NULL)
1604
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1605
" %s\n", name,
1606
avahi_strerror(avahi_server_errno
1607
(((mandos_context*)mc)->server)));
1608
break;
1609
1610
case AVAHI_BROWSER_REMOVE:
1611
break;
1612
1613
case AVAHI_BROWSER_ALL_FOR_NOW:
1614
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1615
if(debug){
1616
fprintf_plus(stderr, "No Mandos server found, still"
1617
" searching...\n");
1618
}
1619
break;
1620
}
1621
}
1622
1623
/* Signal handler that stops main loop after SIGTERM */
1624
static void handle_sigterm(int sig){
1625
if(quit_now){
1626
return;
1627
}
1628
quit_now = 1;
1629
signal_received = sig;
1630
int old_errno = errno;
1631
/* set main loop to exit */
1632
if(simple_poll != NULL){
1633
avahi_simple_poll_quit(simple_poll);
1634
}
1635
errno = old_errno;
1636
}
1637
1638
__attribute__((nonnull, warn_unused_result))
1639
bool get_flags(const char *ifname, struct ifreq *ifr){
1640
int ret;
1641
int old_errno;
1642
1643
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1644
if(s < 0){
1645
old_errno = errno;
1646
perror_plus("socket");
1647
errno = old_errno;
1648
return false;
1649
}
1650
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1651
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1652
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1653
if(ret == -1){
1654
if(debug){
1655
old_errno = errno;
1656
perror_plus("ioctl SIOCGIFFLAGS");
1657
errno = old_errno;
1658
}
1659
close(s);
1660
return false;
1661
}
1662
close(s);
1663
return true;
1664
}
1665
1666
__attribute__((nonnull, warn_unused_result))
1667
bool good_flags(const char *ifname, const struct ifreq *ifr){
1668
1669
/* Reject the loopback device */
1670
if(ifr->ifr_flags & IFF_LOOPBACK){
1671
if(debug){
1672
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1673
ifname);
1674
}
1675
return false;
1676
}
1677
/* Accept point-to-point devices only if connect_to is specified */
1678
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1679
if(debug){
1680
fprintf_plus(stderr, "Accepting point-to-point interface"
1681
" \"%s\"\n", ifname);
1682
}
1683
return true;
1684
}
1685
/* Otherwise, reject non-broadcast-capable devices */
1686
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1687
if(debug){
1688
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1689
" \"%s\"\n", ifname);
1690
}
1691
return false;
1692
}
1693
/* Reject non-ARP interfaces (including dummy interfaces) */
1694
if(ifr->ifr_flags & IFF_NOARP){
1695
if(debug){
1696
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1697
ifname);
1698
}
1699
return false;
1700
}
1701
1702
/* Accept this device */
1703
if(debug){
1704
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1705
}
1706
return true;
1707
}
1708
1709
/*
1710
* This function determines if a directory entry in /sys/class/net
1711
* corresponds to an acceptable network device.
1712
* (This function is passed to scandir(3) as a filter function.)
1713
*/
1714
__attribute__((nonnull, warn_unused_result))
1715
int good_interface(const struct dirent *if_entry){
1716
if(if_entry->d_name[0] == '.'){
1717
return 0;
1718
}
1719
1720
struct ifreq ifr;
1721
if(not get_flags(if_entry->d_name, &ifr)){
1722
if(debug){
1723
fprintf_plus(stderr, "Failed to get flags for interface "
1724
"\"%s\"\n", if_entry->d_name);
1725
}
1726
return 0;
1727
}
1728
1729
if(not good_flags(if_entry->d_name, &ifr)){
1730
return 0;
1731
}
1732
return 1;
1733
}
1734
1735
/*
1736
* This function determines if a network interface is up.
1737
*/
1738
__attribute__((nonnull, warn_unused_result))
1739
bool interface_is_up(const char *interface){
1740
struct ifreq ifr;
1741
if(not get_flags(interface, &ifr)){
1742
if(debug){
1743
fprintf_plus(stderr, "Failed to get flags for interface "
1744
"\"%s\"\n", interface);
1745
}
1746
return false;
1747
}
1748
1749
return (bool)(ifr.ifr_flags & IFF_UP);
1750
}
1751
1752
/*
1753
* This function determines if a network interface is running
1754
*/
1755
__attribute__((nonnull, warn_unused_result))
1756
bool interface_is_running(const char *interface){
1757
struct ifreq ifr;
1758
if(not get_flags(interface, &ifr)){
1759
if(debug){
1760
fprintf_plus(stderr, "Failed to get flags for interface "
1761
"\"%s\"\n", interface);
1762
}
1763
return false;
1764
}
1765
1766
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1767
}
1768
1769
__attribute__((nonnull, pure, warn_unused_result))
1770
int notdotentries(const struct dirent *direntry){
1771
/* Skip "." and ".." */
1772
if(direntry->d_name[0] == '.'
1773
and (direntry->d_name[1] == '\0'
1774
or (direntry->d_name[1] == '.'
1775
and direntry->d_name[2] == '\0'))){
1776
return 0;
1777
}
1778
return 1;
1779
}
1780
1781
/* Is this directory entry a runnable program? */
1782
__attribute__((nonnull, warn_unused_result))
1783
int runnable_hook(const struct dirent *direntry){
1784
int ret;
1785
size_t sret;
1786
struct stat st;
1787
1788
if((direntry->d_name)[0] == '\0'){
1789
/* Empty name? */
1790
return 0;
1791
}
1792
1793
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1794
"abcdefghijklmnopqrstuvwxyz"
1795
"0123456789"
1796
"_.-");
1797
if((direntry->d_name)[sret] != '\0'){
1798
/* Contains non-allowed characters */
1799
if(debug){
1800
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1801
direntry->d_name);
1802
}
1803
return 0;
1804
}
1805
1806
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1807
if(ret == -1){
1808
if(debug){
1809
perror_plus("Could not stat hook");
1810
}
1811
return 0;
1812
}
1813
if(not (S_ISREG(st.st_mode))){
1814
/* Not a regular file */
1815
if(debug){
1816
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1817
direntry->d_name);
1818
}
1819
return 0;
1820
}
1821
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1822
/* Not executable */
1823
if(debug){
1824
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1825
direntry->d_name);
1826
}
1827
return 0;
1828
}
1829
if(debug){
1830
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1831
direntry->d_name);
1832
}
1833
return 1;
1834
}
1835
1836
__attribute__((nonnull, warn_unused_result))
1837
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1838
mandos_context *mc){
1839
int ret;
1840
struct timespec now;
1841
struct timespec waited_time;
1842
intmax_t block_time;
1843
1844
while(true){
1845
if(mc->current_server == NULL){
1846
if(debug){
1847
fprintf_plus(stderr, "Wait until first server is found."
1848
" No timeout!\n");
1849
}
1850
ret = avahi_simple_poll_iterate(s, -1);
1851
} else {
1852
if(debug){
1853
fprintf_plus(stderr, "Check current_server if we should run"
1854
" it, or wait\n");
1855
}
1856
/* the current time */
1857
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1858
if(ret == -1){
1859
perror_plus("clock_gettime");
1860
return -1;
1861
}
1862
/* Calculating in ms how long time between now and server
1863
who we visted longest time ago. Now - last seen. */
1864
waited_time.tv_sec = (now.tv_sec
1865
- mc->current_server->last_seen.tv_sec);
1866
waited_time.tv_nsec = (now.tv_nsec
1867
- mc->current_server->last_seen.tv_nsec);
1868
/* total time is 10s/10,000ms.
1869
Converting to s from ms by dividing by 1,000,
1870
and ns to ms by dividing by 1,000,000. */
1871
block_time = ((retry_interval
1872
- ((intmax_t)waited_time.tv_sec * 1000))
1873
- ((intmax_t)waited_time.tv_nsec / 1000000));
1874
1875
if(debug){
1876
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1877
block_time);
1878
}
1879
1880
if(block_time <= 0){
1881
ret = start_mandos_communication(mc->current_server->ip,
1882
mc->current_server->port,
1883
mc->current_server->if_index,
1884
mc->current_server->af, mc);
1885
if(ret == 0){
1886
avahi_simple_poll_quit(s);
1887
return 0;
1888
}
1889
ret = clock_gettime(CLOCK_MONOTONIC,
1890
&mc->current_server->last_seen);
1891
if(ret == -1){
1892
perror_plus("clock_gettime");
1893
return -1;
1894
}
1895
mc->current_server = mc->current_server->next;
1896
block_time = 0; /* Call avahi to find new Mandos
1897
servers, but don't block */
1898
}
1899
1900
ret = avahi_simple_poll_iterate(s, (int)block_time);
1901
}
1902
if(ret != 0){
1903
if(ret > 0 or errno != EINTR){
1904
return (ret != 1) ? ret : 0;
1905
}
1906
}
1907
}
1908
}
1909
1910
__attribute__((nonnull))
1911
void run_network_hooks(const char *mode, const char *interface,
1912
const float delay){
1913
struct dirent **direntries = NULL;
1914
if(hookdir_fd == -1){
1915
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1916
| O_CLOEXEC);
1917
if(hookdir_fd == -1){
1918
if(errno == ENOENT){
1919
if(debug){
1920
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1921
" found\n", hookdir);
1922
}
1923
} else {
1924
perror_plus("open");
1925
}
1926
return;
1927
}
1928
}
1929
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1930
if(devnull == -1){
1931
perror_plus("open(\"/dev/null\", O_RDONLY)");
1932
return;
1933
}
1934
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1935
runnable_hook, alphasort);
1936
if(numhooks == -1){
1937
perror_plus("scandir");
1938
close(devnull);
1939
return;
1940
}
1941
struct dirent *direntry;
1942
int ret;
1943
for(int i = 0; i < numhooks; i++){
1944
direntry = direntries[i];
1945
if(debug){
1946
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1947
direntry->d_name);
1948
}
1949
pid_t hook_pid = fork();
1950
if(hook_pid == 0){
1951
/* Child */
1952
/* Raise privileges */
1953
errno = raise_privileges_permanently();
1954
if(errno != 0){
1955
perror_plus("Failed to raise privileges");
1956
_exit(EX_NOPERM);
1957
}
1958
/* Set group */
1959
errno = 0;
1960
ret = setgid(0);
1961
if(ret == -1){
1962
perror_plus("setgid");
1963
_exit(EX_NOPERM);
1964
}
1965
/* Reset supplementary groups */
1966
errno = 0;
1967
ret = setgroups(0, NULL);
1968
if(ret == -1){
1969
perror_plus("setgroups");
1970
_exit(EX_NOPERM);
1971
}
1972
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1973
if(ret == -1){
1974
perror_plus("setenv");
1975
_exit(EX_OSERR);
1976
}
1977
ret = setenv("DEVICE", interface, 1);
1978
if(ret == -1){
1979
perror_plus("setenv");
1980
_exit(EX_OSERR);
1981
}
1982
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1983
if(ret == -1){
1984
perror_plus("setenv");
1985
_exit(EX_OSERR);
1986
}
1987
ret = setenv("MODE", mode, 1);
1988
if(ret == -1){
1989
perror_plus("setenv");
1990
_exit(EX_OSERR);
1991
}
1992
char *delaystring;
1993
ret = asprintf(&delaystring, "%f", (double)delay);
1994
if(ret == -1){
1995
perror_plus("asprintf");
1996
_exit(EX_OSERR);
1997
}
1998
ret = setenv("DELAY", delaystring, 1);
1999
if(ret == -1){
2000
free(delaystring);
2001
perror_plus("setenv");
2002
_exit(EX_OSERR);
2003
}
2004
free(delaystring);
2005
if(connect_to != NULL){
2006
ret = setenv("CONNECT", connect_to, 1);
2007
if(ret == -1){
2008
perror_plus("setenv");
2009
_exit(EX_OSERR);
2010
}
2011
}
2012
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2013
direntry->d_name,
2014
O_RDONLY));
2015
if(hook_fd == -1){
2016
perror_plus("openat");
2017
_exit(EXIT_FAILURE);
2018
}
2019
if(close(hookdir_fd) == -1){
2020
perror_plus("close");
2021
_exit(EXIT_FAILURE);
2022
}
2023
ret = dup2(devnull, STDIN_FILENO);
2024
if(ret == -1){
2025
perror_plus("dup2(devnull, STDIN_FILENO)");
2026
_exit(EX_OSERR);
2027
}
2028
ret = close(devnull);
2029
if(ret == -1){
2030
perror_plus("close");
2031
_exit(EX_OSERR);
2032
}
2033
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2034
if(ret == -1){
2035
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2036
_exit(EX_OSERR);
2037
}
2038
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2039
environ) == -1){
2040
perror_plus("fexecve");
2041
_exit(EXIT_FAILURE);
2042
}
2043
} else {
2044
if(hook_pid == -1){
2045
perror_plus("fork");
2046
free(direntry);
2047
continue;
2048
}
2049
int status;
2050
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2051
perror_plus("waitpid");
2052
free(direntry);
2053
continue;
2054
}
2055
if(WIFEXITED(status)){
2056
if(WEXITSTATUS(status) != 0){
2057
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2058
" with status %d\n", direntry->d_name,
2059
WEXITSTATUS(status));
2060
free(direntry);
2061
continue;
2062
}
2063
} else if(WIFSIGNALED(status)){
2064
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2065
" signal %d\n", direntry->d_name,
2066
WTERMSIG(status));
2067
free(direntry);
2068
continue;
2069
} else {
2070
fprintf_plus(stderr, "Warning: network hook \"%s\""
2071
" crashed\n", direntry->d_name);
2072
free(direntry);
2073
continue;
2074
}
2075
}
2076
if(debug){
2077
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2078
direntry->d_name);
2079
}
2080
free(direntry);
2081
}
2082
free(direntries);
2083
if(close(hookdir_fd) == -1){
2084
perror_plus("close");
2085
} else {
2086
hookdir_fd = -1;
2087
}
2088
close(devnull);
2089
}
2090
2091
__attribute__((nonnull, warn_unused_result))
2092
int bring_up_interface(const char *const interface,
2093
const float delay){
2094
int old_errno = errno;
2095
int ret;
2096
struct ifreq network;
2097
unsigned int if_index = if_nametoindex(interface);
2098
if(if_index == 0){
2099
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2100
errno = old_errno;
2101
return ENXIO;
2102
}
2103
2104
if(quit_now){
2105
errno = old_errno;
2106
return EINTR;
2107
}
2108
2109
if(not interface_is_up(interface)){
2110
int ret_errno = 0;
2111
int ioctl_errno = 0;
2112
if(not get_flags(interface, &network)){
2113
ret_errno = errno;
2114
fprintf_plus(stderr, "Failed to get flags for interface "
2115
"\"%s\"\n", interface);
2116
errno = old_errno;
2117
return ret_errno;
2118
}
2119
network.ifr_flags |= IFF_UP; /* set flag */
2120
2121
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2122
if(sd == -1){
2123
ret_errno = errno;
2124
perror_plus("socket");
2125
errno = old_errno;
2126
return ret_errno;
2127
}
2128
2129
if(quit_now){
2130
ret = close(sd);
2131
if(ret == -1){
2132
perror_plus("close");
2133
}
2134
errno = old_errno;
2135
return EINTR;
2136
}
2137
2138
if(debug){
2139
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2140
interface);
2141
}
2142
2143
/* Raise privileges */
2144
ret_errno = raise_privileges();
2145
if(ret_errno != 0){
2146
errno = ret_errno;
2147
perror_plus("Failed to raise privileges");
2148
}
2149
2150
#ifdef __linux__
2151
int ret_linux;
2152
bool restore_loglevel = false;
2153
if(ret_errno == 0){
2154
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2155
messages about the network interface to mess up the prompt */
2156
ret_linux = klogctl(8, NULL, 5);
2157
if(ret_linux == -1){
2158
perror_plus("klogctl");
2159
} else {
2160
restore_loglevel = true;
2161
}
2162
}
2163
#endif /* __linux__ */
2164
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2165
ioctl_errno = errno;
2166
#ifdef __linux__
2167
if(restore_loglevel){
2168
ret_linux = klogctl(7, NULL, 0);
2169
if(ret_linux == -1){
2170
perror_plus("klogctl");
2171
}
2172
}
2173
#endif /* __linux__ */
2174
2175
/* If raise_privileges() succeeded above */
2176
if(ret_errno == 0){
2177
/* Lower privileges */
2178
ret_errno = lower_privileges();
2179
if(ret_errno != 0){
2180
errno = ret_errno;
2181
perror_plus("Failed to lower privileges");
2182
}
2183
}
2184
2185
/* Close the socket */
2186
ret = close(sd);
2187
if(ret == -1){
2188
perror_plus("close");
2189
}
2190
2191
if(ret_setflags == -1){
2192
errno = ioctl_errno;
2193
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2194
errno = old_errno;
2195
return ioctl_errno;
2196
}
2197
} else if(debug){
2198
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2199
interface);
2200
}
2201
2202
/* Sleep checking until interface is running.
2203
Check every 0.25s, up to total time of delay */
2204
for(int i = 0; i < delay * 4; i++){
2205
if(interface_is_running(interface)){
2206
break;
2207
}
2208
struct timespec sleeptime = { .tv_nsec = 250000000 };
2209
ret = nanosleep(&sleeptime, NULL);
2210
if(ret == -1 and errno != EINTR){
2211
perror_plus("nanosleep");
2212
}
2213
}
2214
2215
errno = old_errno;
2216
return 0;
2217
}
2218
2219
__attribute__((nonnull, warn_unused_result))
2220
int take_down_interface(const char *const interface){
2221
int old_errno = errno;
2222
struct ifreq network;
2223
unsigned int if_index = if_nametoindex(interface);
2224
if(if_index == 0){
2225
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2226
errno = old_errno;
2227
return ENXIO;
2228
}
2229
if(interface_is_up(interface)){
2230
int ret_errno = 0;
2231
int ioctl_errno = 0;
2232
if(not get_flags(interface, &network) and debug){
2233
ret_errno = errno;
2234
fprintf_plus(stderr, "Failed to get flags for interface "
2235
"\"%s\"\n", interface);
2236
errno = old_errno;
2237
return ret_errno;
2238
}
2239
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2240
2241
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2242
if(sd == -1){
2243
ret_errno = errno;
2244
perror_plus("socket");
2245
errno = old_errno;
2246
return ret_errno;
2247
}
2248
2249
if(debug){
2250
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2251
interface);
2252
}
2253
2254
/* Raise privileges */
2255
ret_errno = raise_privileges();
2256
if(ret_errno != 0){
2257
errno = ret_errno;
2258
perror_plus("Failed to raise privileges");
2259
}
2260
2261
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2262
ioctl_errno = errno;
2263
2264
/* If raise_privileges() succeeded above */
2265
if(ret_errno == 0){
2266
/* Lower privileges */
2267
ret_errno = lower_privileges();
2268
if(ret_errno != 0){
2269
errno = ret_errno;
2270
perror_plus("Failed to lower privileges");
2271
}
2272
}
2273
2274
/* Close the socket */
2275
int ret = close(sd);
2276
if(ret == -1){
2277
perror_plus("close");
2278
}
2279
2280
if(ret_setflags == -1){
2281
errno = ioctl_errno;
2282
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2283
errno = old_errno;
2284
return ioctl_errno;
2285
}
2286
} else if(debug){
2287
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2288
interface);
2289
}
2290
2291
errno = old_errno;
2292
return 0;
2293
}
2294
2295
int main(int argc, char *argv[]){
2296
mandos_context mc = { .server = NULL, .dh_bits = 0,
2297
.priority = "SECURE256:!CTYPE-X.509"
2298
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2299
.current_server = NULL, .interfaces = NULL,
2300
.interfaces_size = 0 };
2301
AvahiSServiceBrowser *sb = NULL;
2302
error_t ret_errno;
2303
int ret;
2304
intmax_t tmpmax;
2305
char *tmp;
2306
int exitcode = EXIT_SUCCESS;
2307
char *interfaces_to_take_down = NULL;
2308
size_t interfaces_to_take_down_size = 0;
2309
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2310
char old_tempdir[] = "/tmp/mandosXXXXXX";
2311
char *tempdir = NULL;
2312
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2313
const char *seckey = PATHDIR "/" SECKEY;
2314
const char *pubkey = PATHDIR "/" PUBKEY;
2315
const char *dh_params_file = NULL;
2316
char *interfaces_hooks = NULL;
2317
2318
bool gnutls_initialized = false;
2319
bool gpgme_initialized = false;
2320
float delay = 2.5f;
2321
double retry_interval = 10; /* 10s between trying a server and
2322
retrying the same server again */
2323
2324
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2325
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2326
2327
uid = getuid();
2328
gid = getgid();
2329
2330
/* Lower any group privileges we might have, just to be safe */
2331
errno = 0;
2332
ret = setgid(gid);
2333
if(ret == -1){
2334
perror_plus("setgid");
2335
}
2336
2337
/* Lower user privileges (temporarily) */
2338
errno = 0;
2339
ret = seteuid(uid);
2340
if(ret == -1){
2341
perror_plus("seteuid");
2342
}
2343
2344
if(quit_now){
2345
goto end;
2346
}
2347
2348
{
2349
struct argp_option options[] = {
2350
{ .name = "debug", .key = 128,
2351
.doc = "Debug mode", .group = 3 },
2352
{ .name = "connect", .key = 'c',
2353
.arg = "ADDRESS:PORT",
2354
.doc = "Connect directly to a specific Mandos server",
2355
.group = 1 },
2356
{ .name = "interface", .key = 'i',
2357
.arg = "NAME",
2358
.doc = "Network interface that will be used to search for"
2359
" Mandos servers",
2360
.group = 1 },
2361
{ .name = "seckey", .key = 's',
2362
.arg = "FILE",
2363
.doc = "OpenPGP secret key file base name",
2364
.group = 1 },
2365
{ .name = "pubkey", .key = 'p',
2366
.arg = "FILE",
2367
.doc = "OpenPGP public key file base name",
2368
.group = 2 },
2369
{ .name = "dh-bits", .key = 129,
2370
.arg = "BITS",
2371
.doc = "Bit length of the prime number used in the"
2372
" Diffie-Hellman key exchange",
2373
.group = 2 },
2374
{ .name = "dh-params", .key = 134,
2375
.arg = "FILE",
2376
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2377
" for the Diffie-Hellman key exchange",
2378
.group = 2 },
2379
{ .name = "priority", .key = 130,
2380
.arg = "STRING",
2381
.doc = "GnuTLS priority string for the TLS handshake",
2382
.group = 1 },
2383
{ .name = "delay", .key = 131,
2384
.arg = "SECONDS",
2385
.doc = "Maximum delay to wait for interface startup",
2386
.group = 2 },
2387
{ .name = "retry", .key = 132,
2388
.arg = "SECONDS",
2389
.doc = "Retry interval used when denied by the Mandos server",
2390
.group = 2 },
2391
{ .name = "network-hook-dir", .key = 133,
2392
.arg = "DIR",
2393
.doc = "Directory where network hooks are located",
2394
.group = 2 },
2395
/*
2396
* These reproduce what we would get without ARGP_NO_HELP
2397
*/
2398
{ .name = "help", .key = '?',
2399
.doc = "Give this help list", .group = -1 },
2400
{ .name = "usage", .key = -3,
2401
.doc = "Give a short usage message", .group = -1 },
2402
{ .name = "version", .key = 'V',
2403
.doc = "Print program version", .group = -1 },
2404
{ .name = NULL }
2405
};
2406
2407
error_t parse_opt(int key, char *arg,
2408
struct argp_state *state){
2409
errno = 0;
2410
switch(key){
2411
case 128: /* --debug */
2412
debug = true;
2413
break;
2414
case 'c': /* --connect */
2415
connect_to = arg;
2416
break;
2417
case 'i': /* --interface */
2418
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2419
arg, (int)',');
2420
if(ret_errno != 0){
2421
argp_error(state, "%s", strerror(ret_errno));
2422
}
2423
break;
2424
case 's': /* --seckey */
2425
seckey = arg;
2426
break;
2427
case 'p': /* --pubkey */
2428
pubkey = arg;
2429
break;
2430
case 129: /* --dh-bits */
2431
errno = 0;
2432
tmpmax = strtoimax(arg, &tmp, 10);
2433
if(errno != 0 or tmp == arg or *tmp != '\0'
2434
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2435
argp_error(state, "Bad number of DH bits");
2436
}
2437
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2438
break;
2439
case 134: /* --dh-params */
2440
dh_params_file = arg;
2441
break;
2442
case 130: /* --priority */
2443
mc.priority = arg;
2444
break;
2445
case 131: /* --delay */
2446
errno = 0;
2447
delay = strtof(arg, &tmp);
2448
if(errno != 0 or tmp == arg or *tmp != '\0'){
2449
argp_error(state, "Bad delay");
2450
}
2451
case 132: /* --retry */
2452
errno = 0;
2453
retry_interval = strtod(arg, &tmp);
2454
if(errno != 0 or tmp == arg or *tmp != '\0'
2455
or (retry_interval * 1000) > INT_MAX
2456
or retry_interval < 0){
2457
argp_error(state, "Bad retry interval");
2458
}
2459
break;
2460
case 133: /* --network-hook-dir */
2461
hookdir = arg;
2462
break;
2463
/*
2464
* These reproduce what we would get without ARGP_NO_HELP
2465
*/
2466
case '?': /* --help */
2467
argp_state_help(state, state->out_stream,
2468
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2469
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2470
case -3: /* --usage */
2471
argp_state_help(state, state->out_stream,
2472
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2473
case 'V': /* --version */
2474
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2475
exit(argp_err_exit_status);
2476
break;
2477
default:
2478
return ARGP_ERR_UNKNOWN;
2479
}
2480
return errno;
2481
}
2482
2483
struct argp argp = { .options = options, .parser = parse_opt,
2484
.args_doc = "",
2485
.doc = "Mandos client -- Get and decrypt"
2486
" passwords from a Mandos server" };
2487
ret_errno = argp_parse(&argp, argc, argv,
2488
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2489
switch(ret_errno){
2490
case 0:
2491
break;
2492
case ENOMEM:
2493
default:
2494
errno = ret_errno;
2495
perror_plus("argp_parse");
2496
exitcode = EX_OSERR;
2497
goto end;
2498
case EINVAL:
2499
exitcode = EX_USAGE;
2500
goto end;
2501
}
2502
}
2503
2504
{
2505
/* Work around Debian bug #633582:
2506
<https://bugs.debian.org/633582> */
2507
2508
/* Re-raise privileges */
2509
ret = raise_privileges();
2510
if(ret != 0){
2511
errno = ret;
2512
perror_plus("Failed to raise privileges");
2513
} else {
2514
struct stat st;
2515
2516
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2517
int seckey_fd = open(seckey, O_RDONLY);
2518
if(seckey_fd == -1){
2519
perror_plus("open");
2520
} else {
2521
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2522
if(ret == -1){
2523
perror_plus("fstat");
2524
} else {
2525
if(S_ISREG(st.st_mode)
2526
and st.st_uid == 0 and st.st_gid == 0){
2527
ret = fchown(seckey_fd, uid, gid);
2528
if(ret == -1){
2529
perror_plus("fchown");
2530
}
2531
}
2532
}
2533
close(seckey_fd);
2534
}
2535
}
2536
2537
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2538
int pubkey_fd = open(pubkey, O_RDONLY);
2539
if(pubkey_fd == -1){
2540
perror_plus("open");
2541
} else {
2542
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2543
if(ret == -1){
2544
perror_plus("fstat");
2545
} else {
2546
if(S_ISREG(st.st_mode)
2547
and st.st_uid == 0 and st.st_gid == 0){
2548
ret = fchown(pubkey_fd, uid, gid);
2549
if(ret == -1){
2550
perror_plus("fchown");
2551
}
2552
}
2553
}
2554
close(pubkey_fd);
2555
}
2556
}
2557
2558
if(dh_params_file != NULL
2559
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2560
int dhparams_fd = open(dh_params_file, O_RDONLY);
2561
if(dhparams_fd == -1){
2562
perror_plus("open");
2563
} else {
2564
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2565
if(ret == -1){
2566
perror_plus("fstat");
2567
} else {
2568
if(S_ISREG(st.st_mode)
2569
and st.st_uid == 0 and st.st_gid == 0){
2570
ret = fchown(dhparams_fd, uid, gid);
2571
if(ret == -1){
2572
perror_plus("fchown");
2573
}
2574
}
2575
}
2576
close(dhparams_fd);
2577
}
2578
}
2579
2580
/* Lower privileges */
2581
ret = lower_privileges();
2582
if(ret != 0){
2583
errno = ret;
2584
perror_plus("Failed to lower privileges");
2585
}
2586
}
2587
}
2588
2589
/* Remove invalid interface names (except "none") */
2590
{
2591
char *interface = NULL;
2592
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2593
interface))){
2594
if(strcmp(interface, "none") != 0
2595
and if_nametoindex(interface) == 0){
2596
if(interface[0] != '\0'){
2597
fprintf_plus(stderr, "Not using nonexisting interface"
2598
" \"%s\"\n", interface);
2599
}
2600
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2601
interface = NULL;
2602
}
2603
}
2604
}
2605
2606
/* Run network hooks */
2607
{
2608
if(mc.interfaces != NULL){
2609
interfaces_hooks = malloc(mc.interfaces_size);
2610
if(interfaces_hooks == NULL){
2611
perror_plus("malloc");
2612
goto end;
2613
}
2614
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2615
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2616
}
2617
run_network_hooks("start", interfaces_hooks != NULL ?
2618
interfaces_hooks : "", delay);
2619
}
2620
2621
if(not debug){
2622
avahi_set_log_function(empty_log);
2623
}
2624
2625
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2626
from the signal handler */
2627
/* Initialize the pseudo-RNG for Avahi */
2628
srand((unsigned int) time(NULL));
2629
simple_poll = avahi_simple_poll_new();
2630
if(simple_poll == NULL){
2631
fprintf_plus(stderr,
2632
"Avahi: Failed to create simple poll object.\n");
2633
exitcode = EX_UNAVAILABLE;
2634
goto end;
2635
}
2636
2637
sigemptyset(&sigterm_action.sa_mask);
2638
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2639
if(ret == -1){
2640
perror_plus("sigaddset");
2641
exitcode = EX_OSERR;
2642
goto end;
2643
}
2644
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2645
if(ret == -1){
2646
perror_plus("sigaddset");
2647
exitcode = EX_OSERR;
2648
goto end;
2649
}
2650
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2651
if(ret == -1){
2652
perror_plus("sigaddset");
2653
exitcode = EX_OSERR;
2654
goto end;
2655
}
2656
/* Need to check if the handler is SIG_IGN before handling:
2657
| [[info:libc:Initial Signal Actions]] |
2658
| [[info:libc:Basic Signal Handling]] |
2659
*/
2660
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2661
if(ret == -1){
2662
perror_plus("sigaction");
2663
return EX_OSERR;
2664
}
2665
if(old_sigterm_action.sa_handler != SIG_IGN){
2666
ret = sigaction(SIGINT, &sigterm_action, NULL);
2667
if(ret == -1){
2668
perror_plus("sigaction");
2669
exitcode = EX_OSERR;
2670
goto end;
2671
}
2672
}
2673
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2674
if(ret == -1){
2675
perror_plus("sigaction");
2676
return EX_OSERR;
2677
}
2678
if(old_sigterm_action.sa_handler != SIG_IGN){
2679
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2680
if(ret == -1){
2681
perror_plus("sigaction");
2682
exitcode = EX_OSERR;
2683
goto end;
2684
}
2685
}
2686
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2687
if(ret == -1){
2688
perror_plus("sigaction");
2689
return EX_OSERR;
2690
}
2691
if(old_sigterm_action.sa_handler != SIG_IGN){
2692
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2693
if(ret == -1){
2694
perror_plus("sigaction");
2695
exitcode = EX_OSERR;
2696
goto end;
2697
}
2698
}
2699
2700
/* If no interfaces were specified, make a list */
2701
if(mc.interfaces == NULL){
2702
struct dirent **direntries = NULL;
2703
/* Look for any good interfaces */
2704
ret = scandir(sys_class_net, &direntries, good_interface,
2705
alphasort);
2706
if(ret >= 1){
2707
/* Add all found interfaces to interfaces list */
2708
for(int i = 0; i < ret; ++i){
2709
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2710
direntries[i]->d_name);
2711
if(ret_errno != 0){
2712
errno = ret_errno;
2713
perror_plus("argz_add");
2714
free(direntries[i]);
2715
continue;
2716
}
2717
if(debug){
2718
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2719
direntries[i]->d_name);
2720
}
2721
free(direntries[i]);
2722
}
2723
free(direntries);
2724
} else {
2725
if(ret == 0){
2726
free(direntries);
2727
}
2728
fprintf_plus(stderr, "Could not find a network interface\n");
2729
exitcode = EXIT_FAILURE;
2730
goto end;
2731
}
2732
}
2733
2734
/* Bring up interfaces which are down, and remove any "none"s */
2735
{
2736
char *interface = NULL;
2737
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2738
interface))){
2739
/* If interface name is "none", stop bringing up interfaces.
2740
Also remove all instances of "none" from the list */
2741
if(strcmp(interface, "none") == 0){
2742
argz_delete(&mc.interfaces, &mc.interfaces_size,
2743
interface);
2744
interface = NULL;
2745
while((interface = argz_next(mc.interfaces,
2746
mc.interfaces_size, interface))){
2747
if(strcmp(interface, "none") == 0){
2748
argz_delete(&mc.interfaces, &mc.interfaces_size,
2749
interface);
2750
interface = NULL;
2751
}
2752
}
2753
break;
2754
}
2755
bool interface_was_up = interface_is_up(interface);
2756
errno = bring_up_interface(interface, delay);
2757
if(not interface_was_up){
2758
if(errno != 0){
2759
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2760
" %s\n", interface, strerror(errno));
2761
} else {
2762
errno = argz_add(&interfaces_to_take_down,
2763
&interfaces_to_take_down_size,
2764
interface);
2765
if(errno != 0){
2766
perror_plus("argz_add");
2767
}
2768
}
2769
}
2770
}
2771
if(debug and (interfaces_to_take_down == NULL)){
2772
fprintf_plus(stderr, "No interfaces were brought up\n");
2773
}
2774
}
2775
2776
/* If we only got one interface, explicitly use only that one */
2777
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2778
if(debug){
2779
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2780
mc.interfaces);
2781
}
2782
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2783
}
2784
2785
if(quit_now){
2786
goto end;
2787
}
2788
2789
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2790
if(ret == -1){
2791
fprintf_plus(stderr, "init_gnutls_global failed\n");
2792
exitcode = EX_UNAVAILABLE;
2793
goto end;
2794
} else {
2795
gnutls_initialized = true;
2796
}
2797
2798
if(quit_now){
2799
goto end;
2800
}
2801
2802
/* Try /run/tmp before /tmp */
2803
tempdir = mkdtemp(run_tempdir);
2804
if(tempdir == NULL and errno == ENOENT){
2805
if(debug){
2806
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2807
run_tempdir, old_tempdir);
2808
}
2809
tempdir = mkdtemp(old_tempdir);
2810
}
2811
if(tempdir == NULL){
2812
perror_plus("mkdtemp");
2813
goto end;
2814
}
2815
2816
if(quit_now){
2817
goto end;
2818
}
2819
2820
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2821
fprintf_plus(stderr, "init_gpgme failed\n");
2822
exitcode = EX_UNAVAILABLE;
2823
goto end;
2824
} else {
2825
gpgme_initialized = true;
2826
}
2827
2828
if(quit_now){
2829
goto end;
2830
}
2831
2832
if(connect_to != NULL){
2833
/* Connect directly, do not use Zeroconf */
2834
/* (Mainly meant for debugging) */
2835
char *address = strrchr(connect_to, ':');
2836
2837
if(address == NULL){
2838
fprintf_plus(stderr, "No colon in address\n");
2839
exitcode = EX_USAGE;
2840
goto end;
2841
}
2842
2843
if(quit_now){
2844
goto end;
2845
}
2846
2847
in_port_t port;
2848
errno = 0;
2849
tmpmax = strtoimax(address+1, &tmp, 10);
2850
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2851
or tmpmax != (in_port_t)tmpmax){
2852
fprintf_plus(stderr, "Bad port number\n");
2853
exitcode = EX_USAGE;
2854
goto end;
2855
}
2856
2857
if(quit_now){
2858
goto end;
2859
}
2860
2861
port = (in_port_t)tmpmax;
2862
*address = '\0';
2863
/* Colon in address indicates IPv6 */
2864
int af;
2865
if(strchr(connect_to, ':') != NULL){
2866
af = AF_INET6;
2867
/* Accept [] around IPv6 address - see RFC 5952 */
2868
if(connect_to[0] == '[' and address[-1] == ']')
2869
{
2870
connect_to++;
2871
address[-1] = '\0';
2872
}
2873
} else {
2874
af = AF_INET;
2875
}
2876
address = connect_to;
2877
2878
if(quit_now){
2879
goto end;
2880
}
2881
2882
while(not quit_now){
2883
ret = start_mandos_communication(address, port, if_index, af,
2884
&mc);
2885
if(quit_now or ret == 0){
2886
break;
2887
}
2888
if(debug){
2889
fprintf_plus(stderr, "Retrying in %d seconds\n",
2890
(int)retry_interval);
2891
}
2892
sleep((unsigned int)retry_interval);
2893
}
2894
2895
if(not quit_now){
2896
exitcode = EXIT_SUCCESS;
2897
}
2898
2899
goto end;
2900
}
2901
2902
if(quit_now){
2903
goto end;
2904
}
2905
2906
{
2907
AvahiServerConfig config;
2908
/* Do not publish any local Zeroconf records */
2909
avahi_server_config_init(&config);
2910
config.publish_hinfo = 0;
2911
config.publish_addresses = 0;
2912
config.publish_workstation = 0;
2913
config.publish_domain = 0;
2914
2915
/* Allocate a new server */
2916
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2917
&config, NULL, NULL, &ret);
2918
2919
/* Free the Avahi configuration data */
2920
avahi_server_config_free(&config);
2921
}
2922
2923
/* Check if creating the Avahi server object succeeded */
2924
if(mc.server == NULL){
2925
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2926
avahi_strerror(ret));
2927
exitcode = EX_UNAVAILABLE;
2928
goto end;
2929
}
2930
2931
if(quit_now){
2932
goto end;
2933
}
2934
2935
/* Create the Avahi service browser */
2936
sb = avahi_s_service_browser_new(mc.server, if_index,
2937
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2938
NULL, 0, browse_callback,
2939
(void *)&mc);
2940
if(sb == NULL){
2941
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2942
avahi_strerror(avahi_server_errno(mc.server)));
2943
exitcode = EX_UNAVAILABLE;
2944
goto end;
2945
}
2946
2947
if(quit_now){
2948
goto end;
2949
}
2950
2951
/* Run the main loop */
2952
2953
if(debug){
2954
fprintf_plus(stderr, "Starting Avahi loop search\n");
2955
}
2956
2957
ret = avahi_loop_with_timeout(simple_poll,
2958
(int)(retry_interval * 1000), &mc);
2959
if(debug){
2960
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2961
(ret == 0) ? "successfully" : "with error");
2962
}
2963
2964
end:
2965
2966
if(debug){
2967
if(signal_received){
2968
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
2969
argv[0], signal_received,
2970
strsignal(signal_received));
2971
} else {
2972
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2973
}
2974
}
2975
2976
/* Cleanup things */
2977
free(mc.interfaces);
2978
2979
if(sb != NULL)
2980
avahi_s_service_browser_free(sb);
2981
2982
if(mc.server != NULL)
2983
avahi_server_free(mc.server);
2984
2985
if(simple_poll != NULL)
2986
avahi_simple_poll_free(simple_poll);
2987
2988
if(gnutls_initialized){
2989
gnutls_certificate_free_credentials(mc.cred);
2990
gnutls_dh_params_deinit(mc.dh_params);
2991
}
2992
2993
if(gpgme_initialized){
2994
gpgme_release(mc.ctx);
2995
}
2996
2997
/* Cleans up the circular linked list of Mandos servers the client
2998
has seen */
2999
if(mc.current_server != NULL){
3000
mc.current_server->prev->next = NULL;
3001
while(mc.current_server != NULL){
3002
server *next = mc.current_server->next;
3003
#ifdef __GNUC__
3004
#pragma GCC diagnostic push
3005
#pragma GCC diagnostic ignored "-Wcast-qual"
3006
#endif
3007
free((char *)(mc.current_server->ip));
3008
#ifdef __GNUC__
3009
#pragma GCC diagnostic pop
3010
#endif
3011
free(mc.current_server);
3012
mc.current_server = next;
3013
}
3014
}
3015
3016
/* Re-raise privileges */
3017
{
3018
ret = raise_privileges();
3019
if(ret != 0){
3020
errno = ret;
3021
perror_plus("Failed to raise privileges");
3022
} else {
3023
3024
/* Run network hooks */
3025
run_network_hooks("stop", interfaces_hooks != NULL ?
3026
interfaces_hooks : "", delay);
3027
3028
/* Take down the network interfaces which were brought up */
3029
{
3030
char *interface = NULL;
3031
while((interface = argz_next(interfaces_to_take_down,
3032
interfaces_to_take_down_size,
3033
interface))){
3034
ret = take_down_interface(interface);
3035
if(ret != 0){
3036
errno = ret;
3037
perror_plus("Failed to take down interface");
3038
}
3039
}
3040
if(debug and (interfaces_to_take_down == NULL)){
3041
fprintf_plus(stderr, "No interfaces needed to be taken"
3042
" down\n");
3043
}
3044
}
3045
}
3046
3047
ret = lower_privileges_permanently();
3048
if(ret != 0){
3049
errno = ret;
3050
perror_plus("Failed to lower privileges permanently");
3051
}
3052
}
3053
3054
free(interfaces_to_take_down);
3055
free(interfaces_hooks);
3056
3057
void clean_dir_at(int base, const char * const dirname,
3058
uintmax_t level){
3059
struct dirent **direntries = NULL;
3060
int dret;
3061
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3062
O_RDONLY
3063
| O_NOFOLLOW
3064
| O_DIRECTORY
3065
| O_PATH));
3066
if(dir_fd == -1){
3067
perror_plus("open");
3068
return;
3069
}
3070
int numentries = scandirat(dir_fd, ".", &direntries,
3071
notdotentries, alphasort);
3072
if(numentries >= 0){
3073
for(int i = 0; i < numentries; i++){
3074
if(debug){
3075
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3076
dirname, direntries[i]->d_name);
3077
}
3078
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3079
if(dret == -1){
3080
if(errno == EISDIR){
3081
dret = unlinkat(dir_fd, direntries[i]->d_name,
3082
AT_REMOVEDIR);
3083
}
3084
if((dret == -1) and (errno == ENOTEMPTY)
3085
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3086
== 0) and (level == 0)){
3087
/* Recurse only in this special case */
3088
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3089
dret = 0;
3090
}
3091
if((dret == -1) and (errno != ENOENT)){
3092
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3093
direntries[i]->d_name, strerror(errno));
3094
}
3095
}
3096
free(direntries[i]);
3097
}
3098
3099
/* need to clean even if 0 because man page doesn't specify */
3100
free(direntries);
3101
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3102
if(dret == -1 and errno != ENOENT){
3103
perror_plus("rmdir");
3104
}
3105
} else {
3106
perror_plus("scandirat");
3107
}
3108
close(dir_fd);
3109
}
3110
3111
/* Removes the GPGME temp directory and all files inside */
3112
if(tempdir != NULL){
3113
clean_dir_at(-1, tempdir, 0);
3114
}
3115
3116
if(quit_now){
3117
sigemptyset(&old_sigterm_action.sa_mask);
3118
old_sigterm_action.sa_handler = SIG_DFL;
3119
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3120
&old_sigterm_action,
3121
NULL));
3122
if(ret == -1){
3123
perror_plus("sigaction");
3124
}
3125
do {
3126
ret = raise(signal_received);
3127
} while(ret != 0 and errno == EINTR);
3128
if(ret != 0){
3129
perror_plus("raise");
3130
abort();
3131
}
3132
TEMP_FAILURE_RETRY(pause());
3133
}
3134
3135
return exitcode;
3136
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0