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- Committer: Teddy Hogeborn
- Date: 2018-02-22 18:15:57 UTC
- Revision ID: teddy@recompile.se-20180222181557-yhp7z2pgx9y9nf4b
Mark fallthrough case with comment
* plugin-runner.c (main/parse_opt): Mark case ARGP_KEY_ARG as falling
through (in the case where the argument is not empty).
* plugin-runner.c (main/parse_opt): Mark case ARGP_KEY_ARG as falling
through (in the case where the argument is not empty).
- files added:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- plugins.d
- files removed:
- bad-ca.pem
- 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
ret = close(dhpfile);
617
if(ret == -1){
618
perror_plus("close");
619
}
620
if(params.data == NULL){
621
dhparamsfilename = NULL;
622
}
623
if(dhparamsfilename == NULL){
624
break;
625
}
626
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
627
GNUTLS_X509_FMT_PEM);
628
if(ret != GNUTLS_E_SUCCESS){
629
fprintf_plus(stderr, "Failed to parse DH parameters in file"
630
" \"%s\": %s\n", dhparamsfilename,
631
safer_gnutls_strerror(ret));
632
dhparamsfilename = NULL;
633
}
634
free(params.data);
635
} while(false);
636
}
637
if(dhparamsfilename == NULL){
638
if(mc->dh_bits == 0){
639
/* Find out the optimal number of DH bits */
640
/* Try to read the private key file */
641
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
642
do {
643
int secfile = open(seckeyfilename, O_RDONLY);
644
if(secfile == -1){
645
perror_plus("open");
646
break;
647
}
648
size_t buffer_capacity = 0;
649
while(true){
650
buffer_capacity = incbuffer((char **)&buffer.data,
651
(size_t)buffer.size,
652
(size_t)buffer_capacity);
653
if(buffer_capacity == 0){
654
perror_plus("incbuffer");
655
free(buffer.data);
656
buffer.data = NULL;
657
break;
658
}
659
ssize_t bytes_read = read(secfile,
660
buffer.data + buffer.size,
661
BUFFER_SIZE);
662
/* EOF */
663
if(bytes_read == 0){
664
break;
665
}
666
/* check bytes_read for failure */
667
if(bytes_read < 0){
668
perror_plus("read");
669
free(buffer.data);
670
buffer.data = NULL;
671
break;
672
}
673
buffer.size += (unsigned int)bytes_read;
674
}
675
close(secfile);
676
} while(false);
677
/* If successful, use buffer to parse private key */
678
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
679
if(buffer.data != NULL){
680
{
681
gnutls_openpgp_privkey_t privkey = NULL;
682
ret = gnutls_openpgp_privkey_init(&privkey);
683
if(ret != GNUTLS_E_SUCCESS){
684
fprintf_plus(stderr, "Error initializing OpenPGP key"
685
" structure: %s",
686
safer_gnutls_strerror(ret));
687
free(buffer.data);
688
buffer.data = NULL;
689
} else {
690
ret = gnutls_openpgp_privkey_import
691
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
692
if(ret != GNUTLS_E_SUCCESS){
693
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
694
safer_gnutls_strerror(ret));
695
privkey = NULL;
696
}
697
free(buffer.data);
698
buffer.data = NULL;
699
if(privkey != NULL){
700
/* Use private key to suggest an appropriate
701
sec_param */
702
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
703
gnutls_openpgp_privkey_deinit(privkey);
704
if(debug){
705
fprintf_plus(stderr, "This OpenPGP key implies using"
706
" a GnuTLS security parameter \"%s\".\n",
707
safe_string(gnutls_sec_param_get_name
708
(sec_param)));
709
}
710
}
711
}
712
}
713
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
714
/* Err on the side of caution */
715
sec_param = GNUTLS_SEC_PARAM_ULTRA;
716
if(debug){
717
fprintf_plus(stderr, "Falling back to security parameter"
718
" \"%s\"\n",
719
safe_string(gnutls_sec_param_get_name
720
(sec_param)));
721
}
722
}
723
}
724
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
725
if(uret != 0){
726
mc->dh_bits = uret;
727
if(debug){
728
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
729
" implies %u DH bits; using that.\n",
730
safe_string(gnutls_sec_param_get_name
731
(sec_param)),
732
mc->dh_bits);
733
}
734
} else {
735
fprintf_plus(stderr, "Failed to get implied number of DH"
736
" bits for security parameter \"%s\"): %s\n",
737
safe_string(gnutls_sec_param_get_name
738
(sec_param)),
739
safer_gnutls_strerror(ret));
740
goto globalfail;
741
}
742
} else if(debug){
743
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
744
mc->dh_bits);
745
}
746
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
747
if(ret != GNUTLS_E_SUCCESS){
748
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
749
" bits): %s\n", mc->dh_bits,
750
safer_gnutls_strerror(ret));
751
goto globalfail;
752
}
753
}
754
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
755
756
return 0;
757
758
globalfail:
759
760
gnutls_certificate_free_credentials(mc->cred);
761
gnutls_dh_params_deinit(mc->dh_params);
762
return -1;
763
}
764
765
__attribute__((nonnull, warn_unused_result))
766
static int init_gnutls_session(gnutls_session_t *session,
767
mandos_context *mc){
768
int ret;
769
/* GnuTLS session creation */
770
do {
771
ret = gnutls_init(session, GNUTLS_SERVER);
772
if(quit_now){
773
return -1;
774
}
775
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
776
if(ret != GNUTLS_E_SUCCESS){
777
fprintf_plus(stderr,
778
"Error in GnuTLS session initialization: %s\n",
779
safer_gnutls_strerror(ret));
780
}
781
782
{
783
const char *err;
784
do {
785
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
786
if(quit_now){
787
gnutls_deinit(*session);
788
return -1;
789
}
790
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
791
if(ret != GNUTLS_E_SUCCESS){
792
fprintf_plus(stderr, "Syntax error at: %s\n", err);
793
fprintf_plus(stderr, "GnuTLS error: %s\n",
794
safer_gnutls_strerror(ret));
795
gnutls_deinit(*session);
796
return -1;
797
}
798
}
799
800
do {
801
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
802
mc->cred);
803
if(quit_now){
804
gnutls_deinit(*session);
805
return -1;
806
}
807
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
808
if(ret != GNUTLS_E_SUCCESS){
809
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
810
safer_gnutls_strerror(ret));
811
gnutls_deinit(*session);
812
return -1;
813
}
814
815
/* ignore client certificate if any. */
816
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
817
818
return 0;
819
}
820
821
/* Avahi log function callback */
822
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
823
__attribute__((unused)) const char *txt){}
824
825
/* Set effective uid to 0, return errno */
826
__attribute__((warn_unused_result))
827
int raise_privileges(void){
828
int old_errno = errno;
829
int ret = 0;
830
if(seteuid(0) == -1){
831
ret = errno;
832
}
833
errno = old_errno;
834
return ret;
835
}
836
837
/* Set effective and real user ID to 0. Return errno. */
838
__attribute__((warn_unused_result))
839
int raise_privileges_permanently(void){
840
int old_errno = errno;
841
int ret = raise_privileges();
842
if(ret != 0){
843
errno = old_errno;
844
return ret;
845
}
846
if(setuid(0) == -1){
847
ret = errno;
848
}
849
errno = old_errno;
850
return ret;
851
}
852
853
/* Set effective user ID to unprivileged saved user ID */
854
__attribute__((warn_unused_result))
855
int lower_privileges(void){
856
int old_errno = errno;
857
int ret = 0;
858
if(seteuid(uid) == -1){
859
ret = errno;
860
}
861
errno = old_errno;
862
return ret;
863
}
864
865
/* Lower privileges permanently */
866
__attribute__((warn_unused_result))
867
int lower_privileges_permanently(void){
868
int old_errno = errno;
869
int ret = 0;
870
if(setuid(uid) == -1){
871
ret = errno;
872
}
873
errno = old_errno;
874
return ret;
875
}
876
877
/* Helper function to add_local_route() and delete_local_route() */
878
__attribute__((nonnull, warn_unused_result))
879
static bool add_delete_local_route(const bool add,
880
const char *address,
881
AvahiIfIndex if_index){
882
int ret;
883
char helper[] = "mandos-client-iprouteadddel";
884
char add_arg[] = "add";
885
char delete_arg[] = "delete";
886
char debug_flag[] = "--debug";
887
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
888
if(pluginhelperdir == NULL){
889
if(debug){
890
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
891
" variable not set; cannot run helper\n");
892
}
893
return false;
894
}
895
896
char interface[IF_NAMESIZE];
897
if(if_indextoname((unsigned int)if_index, interface) == NULL){
898
perror_plus("if_indextoname");
899
return false;
900
}
901
902
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
903
if(devnull == -1){
904
perror_plus("open(\"/dev/null\", O_RDONLY)");
905
return false;
906
}
907
pid_t pid = fork();
908
if(pid == 0){
909
/* Child */
910
/* Raise privileges */
911
errno = raise_privileges_permanently();
912
if(errno != 0){
913
perror_plus("Failed to raise privileges");
914
/* _exit(EX_NOPERM); */
915
} else {
916
/* Set group */
917
errno = 0;
918
ret = setgid(0);
919
if(ret == -1){
920
perror_plus("setgid");
921
_exit(EX_NOPERM);
922
}
923
/* Reset supplementary groups */
924
errno = 0;
925
ret = setgroups(0, NULL);
926
if(ret == -1){
927
perror_plus("setgroups");
928
_exit(EX_NOPERM);
929
}
930
}
931
ret = dup2(devnull, STDIN_FILENO);
932
if(ret == -1){
933
perror_plus("dup2(devnull, STDIN_FILENO)");
934
_exit(EX_OSERR);
935
}
936
ret = close(devnull);
937
if(ret == -1){
938
perror_plus("close");
939
_exit(EX_OSERR);
940
}
941
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
942
if(ret == -1){
943
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
944
_exit(EX_OSERR);
945
}
946
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
947
O_RDONLY
948
| O_DIRECTORY
949
| O_PATH
950
| O_CLOEXEC));
951
if(helperdir_fd == -1){
952
perror_plus("open");
953
_exit(EX_UNAVAILABLE);
954
}
955
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
956
helper, O_RDONLY));
957
if(helper_fd == -1){
958
perror_plus("openat");
959
close(helperdir_fd);
960
_exit(EX_UNAVAILABLE);
961
}
962
close(helperdir_fd);
963
#ifdef __GNUC__
964
#pragma GCC diagnostic push
965
#pragma GCC diagnostic ignored "-Wcast-qual"
966
#endif
967
if(fexecve(helper_fd, (char *const [])
968
{ helper, add ? add_arg : delete_arg, (char *)address,
969
interface, debug ? debug_flag : NULL, NULL },
970
environ) == -1){
971
#ifdef __GNUC__
972
#pragma GCC diagnostic pop
973
#endif
974
perror_plus("fexecve");
975
_exit(EXIT_FAILURE);
976
}
977
}
978
if(pid == -1){
979
perror_plus("fork");
980
return false;
981
}
982
int status;
983
pid_t pret = -1;
984
errno = 0;
985
do {
986
pret = waitpid(pid, &status, 0);
987
if(pret == -1 and errno == EINTR and quit_now){
988
int errno_raising = 0;
989
if((errno = raise_privileges()) != 0){
990
errno_raising = errno;
991
perror_plus("Failed to raise privileges in order to"
992
" kill helper program");
993
}
994
if(kill(pid, SIGTERM) == -1){
995
perror_plus("kill");
996
}
997
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
998
perror_plus("Failed to lower privileges after killing"
999
" helper program");
1000
}
1001
return false;
1002
}
1003
} while(pret == -1 and errno == EINTR);
1004
if(pret == -1){
1005
perror_plus("waitpid");
1006
return false;
1007
}
1008
if(WIFEXITED(status)){
1009
if(WEXITSTATUS(status) != 0){
1010
fprintf_plus(stderr, "Error: iprouteadddel exited"
1011
" with status %d\n", WEXITSTATUS(status));
1012
return false;
1013
}
1014
return true;
1015
}
1016
if(WIFSIGNALED(status)){
1017
fprintf_plus(stderr, "Error: iprouteadddel died by"
1018
" signal %d\n", WTERMSIG(status));
1019
return false;
1020
}
1021
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1022
return false;
1023
}
1024
1025
__attribute__((nonnull, warn_unused_result))
1026
static bool add_local_route(const char *address,
1027
AvahiIfIndex if_index){
1028
if(debug){
1029
fprintf_plus(stderr, "Adding route to %s\n", address);
1030
}
1031
return add_delete_local_route(true, address, if_index);
1032
}
1033
1034
__attribute__((nonnull, warn_unused_result))
1035
static bool delete_local_route(const char *address,
1036
AvahiIfIndex if_index){
1037
if(debug){
1038
fprintf_plus(stderr, "Removing route to %s\n", address);
1039
}
1040
return add_delete_local_route(false, address, if_index);
1041
}
1042
1043
/* Called when a Mandos server is found */
1044
__attribute__((nonnull, warn_unused_result))
1045
static int start_mandos_communication(const char *ip, in_port_t port,
1046
AvahiIfIndex if_index,
1047
int af, mandos_context *mc){
1048
int ret, tcp_sd = -1;
1049
ssize_t sret;
1050
struct sockaddr_storage to;
1051
char *buffer = NULL;
1052
char *decrypted_buffer = NULL;
1053
size_t buffer_length = 0;
1054
size_t buffer_capacity = 0;
1055
size_t written;
1056
int retval = -1;
1057
gnutls_session_t session;
1058
int pf; /* Protocol family */
1059
bool route_added = false;
1060
1061
errno = 0;
1062
1063
if(quit_now){
1064
errno = EINTR;
1065
return -1;
1066
}
1067
1068
switch(af){
1069
case AF_INET6:
1070
pf = PF_INET6;
1071
break;
1072
case AF_INET:
1073
pf = PF_INET;
1074
break;
1075
default:
1076
fprintf_plus(stderr, "Bad address family: %d\n", af);
1077
errno = EINVAL;
1078
return -1;
1079
}
1080
1081
/* If the interface is specified and we have a list of interfaces */
1082
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1083
/* Check if the interface is one of the interfaces we are using */
1084
bool match = false;
1085
{
1086
char *interface = NULL;
1087
while((interface = argz_next(mc->interfaces,
1088
mc->interfaces_size,
1089
interface))){
1090
if(if_nametoindex(interface) == (unsigned int)if_index){
1091
match = true;
1092
break;
1093
}
1094
}
1095
}
1096
if(not match){
1097
/* This interface does not match any in the list, so we don't
1098
connect to the server */
1099
if(debug){
1100
char interface[IF_NAMESIZE];
1101
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1102
perror_plus("if_indextoname");
1103
} else {
1104
fprintf_plus(stderr, "Skipping server on non-used interface"
1105
" \"%s\"\n",
1106
if_indextoname((unsigned int)if_index,
1107
interface));
1108
}
1109
}
1110
return -1;
1111
}
1112
}
1113
1114
ret = init_gnutls_session(&session, mc);
1115
if(ret != 0){
1116
return -1;
1117
}
1118
1119
if(debug){
1120
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1121
PRIuMAX "\n", ip, (uintmax_t)port);
1122
}
1123
1124
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1125
if(tcp_sd < 0){
1126
int e = errno;
1127
perror_plus("socket");
1128
errno = e;
1129
goto mandos_end;
1130
}
1131
1132
if(quit_now){
1133
errno = EINTR;
1134
goto mandos_end;
1135
}
1136
1137
if(af == AF_INET6){
1138
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1139
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1140
ret = inet_pton(af, ip, &to6->sin6_addr);
1141
} else { /* IPv4 */
1142
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1143
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1144
ret = inet_pton(af, ip, &to4->sin_addr);
1145
}
1146
if(ret < 0 ){
1147
int e = errno;
1148
perror_plus("inet_pton");
1149
errno = e;
1150
goto mandos_end;
1151
}
1152
if(ret == 0){
1153
int e = errno;
1154
fprintf_plus(stderr, "Bad address: %s\n", ip);
1155
errno = e;
1156
goto mandos_end;
1157
}
1158
if(af == AF_INET6){
1159
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1160
if(IN6_IS_ADDR_LINKLOCAL
1161
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1162
if(if_index == AVAHI_IF_UNSPEC){
1163
fprintf_plus(stderr, "An IPv6 link-local address is"
1164
" incomplete without a network interface\n");
1165
errno = EINVAL;
1166
goto mandos_end;
1167
}
1168
/* Set the network interface number as scope */
1169
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1170
}
1171
} else {
1172
((struct sockaddr_in *)&to)->sin_port = htons(port);
1173
}
1174
1175
if(quit_now){
1176
errno = EINTR;
1177
goto mandos_end;
1178
}
1179
1180
if(debug){
1181
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1182
char interface[IF_NAMESIZE];
1183
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1184
perror_plus("if_indextoname");
1185
} else {
1186
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1187
"\n", ip, interface, (uintmax_t)port);
1188
}
1189
} else {
1190
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1191
ip, (uintmax_t)port);
1192
}
1193
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1194
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1195
if(af == AF_INET6){
1196
ret = getnameinfo((struct sockaddr *)&to,
1197
sizeof(struct sockaddr_in6),
1198
addrstr, sizeof(addrstr), NULL, 0,
1199
NI_NUMERICHOST);
1200
} else {
1201
ret = getnameinfo((struct sockaddr *)&to,
1202
sizeof(struct sockaddr_in),
1203
addrstr, sizeof(addrstr), NULL, 0,
1204
NI_NUMERICHOST);
1205
}
1206
if(ret == EAI_SYSTEM){
1207
perror_plus("getnameinfo");
1208
} else if(ret != 0) {
1209
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1210
} else if(strcmp(addrstr, ip) != 0){
1211
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1212
}
1213
}
1214
1215
if(quit_now){
1216
errno = EINTR;
1217
goto mandos_end;
1218
}
1219
1220
while(true){
1221
if(af == AF_INET6){
1222
ret = connect(tcp_sd, (struct sockaddr *)&to,
1223
sizeof(struct sockaddr_in6));
1224
} else {
1225
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1226
sizeof(struct sockaddr_in));
1227
}
1228
if(ret < 0){
1229
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1230
and if_index != AVAHI_IF_UNSPEC
1231
and connect_to == NULL
1232
and not route_added and
1233
((af == AF_INET6 and not
1234
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1235
&to)->sin6_addr)))
1236
or (af == AF_INET and
1237
/* Not a a IPv4LL address */
1238
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1239
& 0xFFFF0000L) != 0xA9FE0000L))){
1240
/* Work around Avahi bug - Avahi does not announce link-local
1241
addresses if it has a global address, so local hosts with
1242
*only* a link-local address (e.g. Mandos clients) cannot
1243
connect to a Mandos server announced by Avahi on a server
1244
host with a global address. Work around this by retrying
1245
with an explicit route added with the server's address.
1246
1247
Avahi bug reference:
1248
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1249
https://bugs.debian.org/587961
1250
*/
1251
if(debug){
1252
fprintf_plus(stderr, "Mandos server unreachable, trying"
1253
" direct route\n");
1254
}
1255
int e = errno;
1256
route_added = add_local_route(ip, if_index);
1257
if(route_added){
1258
continue;
1259
}
1260
errno = e;
1261
}
1262
if(errno != ECONNREFUSED or debug){
1263
int e = errno;
1264
perror_plus("connect");
1265
errno = e;
1266
}
1267
goto mandos_end;
1268
}
1269
1270
if(quit_now){
1271
errno = EINTR;
1272
goto mandos_end;
1273
}
1274
break;
1275
}
1276
1277
const char *out = mandos_protocol_version;
1278
written = 0;
1279
while(true){
1280
size_t out_size = strlen(out);
1281
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1282
out_size - written));
1283
if(ret == -1){
1284
int e = errno;
1285
perror_plus("write");
1286
errno = e;
1287
goto mandos_end;
1288
}
1289
written += (size_t)ret;
1290
if(written < out_size){
1291
continue;
1292
} else {
1293
if(out == mandos_protocol_version){
1294
written = 0;
1295
out = "\r\n";
1296
} else {
1297
break;
1298
}
1299
}
1300
1301
if(quit_now){
1302
errno = EINTR;
1303
goto mandos_end;
1304
}
1305
}
1306
1307
if(debug){
1308
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1309
}
1310
1311
if(quit_now){
1312
errno = EINTR;
1313
goto mandos_end;
1314
}
1315
1316
/* This casting via intptr_t is to eliminate warning about casting
1317
an int to a pointer type. This is exactly how the GnuTLS Guile
1318
function "set-session-transport-fd!" does it. */
1319
gnutls_transport_set_ptr(session,
1320
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1321
1322
if(quit_now){
1323
errno = EINTR;
1324
goto mandos_end;
1325
}
1326
1327
do {
1328
ret = gnutls_handshake(session);
1329
if(quit_now){
1330
errno = EINTR;
1331
goto mandos_end;
1332
}
1333
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1334
1335
if(ret != GNUTLS_E_SUCCESS){
1336
if(debug){
1337
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
1338
gnutls_perror(ret);
1339
}
1340
errno = EPROTO;
1341
goto mandos_end;
1342
}
1343
1344
/* Read OpenPGP packet that contains the wanted password */
1345
1346
if(debug){
1347
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1348
" %s\n", ip);
1349
}
1350
1351
while(true){
1352
1353
if(quit_now){
1354
errno = EINTR;
1355
goto mandos_end;
1356
}
1357
1358
buffer_capacity = incbuffer(&buffer, buffer_length,
1359
buffer_capacity);
1360
if(buffer_capacity == 0){
1361
int e = errno;
1362
perror_plus("incbuffer");
1363
errno = e;
1364
goto mandos_end;
1365
}
1366
1367
if(quit_now){
1368
errno = EINTR;
1369
goto mandos_end;
1370
}
1371
1372
sret = gnutls_record_recv(session, buffer+buffer_length,
1373
BUFFER_SIZE);
1374
if(sret == 0){
1375
break;
1376
}
1377
if(sret < 0){
1378
switch(sret){
1379
case GNUTLS_E_INTERRUPTED:
1380
case GNUTLS_E_AGAIN:
1381
break;
1382
case GNUTLS_E_REHANDSHAKE:
1383
do {
1384
ret = gnutls_handshake(session);
1385
1386
if(quit_now){
1387
errno = EINTR;
1388
goto mandos_end;
1389
}
1390
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1391
if(ret < 0){
1392
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1393
"***\n");
1394
gnutls_perror(ret);
1395
errno = EPROTO;
1396
goto mandos_end;
1397
}
1398
break;
1399
default:
1400
fprintf_plus(stderr, "Unknown error while reading data from"
1401
" encrypted session with Mandos server\n");
1402
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1403
errno = EIO;
1404
goto mandos_end;
1405
}
1406
} else {
1407
buffer_length += (size_t) sret;
1408
}
1409
}
1410
1411
if(debug){
1412
fprintf_plus(stderr, "Closing TLS session\n");
1413
}
1414
1415
if(quit_now){
1416
errno = EINTR;
1417
goto mandos_end;
1418
}
1419
1420
do {
1421
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1422
if(quit_now){
1423
errno = EINTR;
1424
goto mandos_end;
1425
}
1426
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1427
1428
if(buffer_length > 0){
1429
ssize_t decrypted_buffer_size;
1430
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1431
&decrypted_buffer, mc);
1432
if(decrypted_buffer_size >= 0){
1433
1434
clearerr(stdout);
1435
written = 0;
1436
while(written < (size_t) decrypted_buffer_size){
1437
if(quit_now){
1438
errno = EINTR;
1439
goto mandos_end;
1440
}
1441
1442
ret = (int)fwrite(decrypted_buffer + written, 1,
1443
(size_t)decrypted_buffer_size - written,
1444
stdout);
1445
if(ret == 0 and ferror(stdout)){
1446
int e = errno;
1447
if(debug){
1448
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1449
strerror(errno));
1450
}
1451
errno = e;
1452
goto mandos_end;
1453
}
1454
written += (size_t)ret;
1455
}
1456
ret = fflush(stdout);
1457
if(ret != 0){
1458
int e = errno;
1459
if(debug){
1460
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1461
strerror(errno));
1462
}
1463
errno = e;
1464
goto mandos_end;
1465
}
1466
retval = 0;
1467
}
1468
}
1469
1470
/* Shutdown procedure */
1471
1472
mandos_end:
1473
{
1474
if(route_added){
1475
if(not delete_local_route(ip, if_index)){
1476
fprintf_plus(stderr, "Failed to delete local route to %s on"
1477
" interface %d", ip, if_index);
1478
}
1479
}
1480
int e = errno;
1481
free(decrypted_buffer);
1482
free(buffer);
1483
if(tcp_sd >= 0){
1484
ret = close(tcp_sd);
1485
}
1486
if(ret == -1){
1487
if(e == 0){
1488
e = errno;
1489
}
1490
perror_plus("close");
1491
}
1492
gnutls_deinit(session);
1493
errno = e;
1494
if(quit_now){
1495
errno = EINTR;
1496
retval = -1;
1497
}
1498
}
1499
return retval;
1500
}
1501
1502
static void resolve_callback(AvahiSServiceResolver *r,
1503
AvahiIfIndex interface,
1504
AvahiProtocol proto,
1505
AvahiResolverEvent event,
1506
const char *name,
1507
const char *type,
1508
const char *domain,
1509
const char *host_name,
1510
const AvahiAddress *address,
1511
uint16_t port,
1512
AVAHI_GCC_UNUSED AvahiStringList *txt,
1513
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1514
flags,
1515
void *mc){
1516
if(r == NULL){
1517
return;
1518
}
1519
1520
/* Called whenever a service has been resolved successfully or
1521
timed out */
1522
1523
if(quit_now){
1524
avahi_s_service_resolver_free(r);
1525
return;
1526
}
1527
1528
switch(event){
1529
default:
1530
case AVAHI_RESOLVER_FAILURE:
1531
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1532
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1533
domain,
1534
avahi_strerror(avahi_server_errno
1535
(((mandos_context*)mc)->server)));
1536
break;
1537
1538
case AVAHI_RESOLVER_FOUND:
1539
{
1540
char ip[AVAHI_ADDRESS_STR_MAX];
1541
avahi_address_snprint(ip, sizeof(ip), address);
1542
if(debug){
1543
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1544
PRIdMAX ") on port %" PRIu16 "\n", name,
1545
host_name, ip, (intmax_t)interface, port);
1546
}
1547
int ret = start_mandos_communication(ip, (in_port_t)port,
1548
interface,
1549
avahi_proto_to_af(proto),
1550
mc);
1551
if(ret == 0){
1552
avahi_simple_poll_quit(simple_poll);
1553
} else {
1554
if(not add_server(ip, (in_port_t)port, interface,
1555
avahi_proto_to_af(proto),
1556
&((mandos_context*)mc)->current_server)){
1557
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1558
" list\n", name);
1559
}
1560
}
1561
}
1562
}
1563
avahi_s_service_resolver_free(r);
1564
}
1565
1566
static void browse_callback(AvahiSServiceBrowser *b,
1567
AvahiIfIndex interface,
1568
AvahiProtocol protocol,
1569
AvahiBrowserEvent event,
1570
const char *name,
1571
const char *type,
1572
const char *domain,
1573
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1574
flags,
1575
void *mc){
1576
if(b == NULL){
1577
return;
1578
}
1579
1580
/* Called whenever a new services becomes available on the LAN or
1581
is removed from the LAN */
1582
1583
if(quit_now){
1584
return;
1585
}
1586
1587
switch(event){
1588
default:
1589
case AVAHI_BROWSER_FAILURE:
1590
1591
fprintf_plus(stderr, "(Avahi browser) %s\n",
1592
avahi_strerror(avahi_server_errno
1593
(((mandos_context*)mc)->server)));
1594
avahi_simple_poll_quit(simple_poll);
1595
return;
1596
1597
case AVAHI_BROWSER_NEW:
1598
/* We ignore the returned Avahi resolver object. In the callback
1599
function we free it. If the Avahi server is terminated before
1600
the callback function is called the Avahi server will free the
1601
resolver for us. */
1602
1603
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1604
interface, protocol, name, type,
1605
domain, protocol, 0,
1606
resolve_callback, mc) == NULL)
1607
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1608
" %s\n", name,
1609
avahi_strerror(avahi_server_errno
1610
(((mandos_context*)mc)->server)));
1611
break;
1612
1613
case AVAHI_BROWSER_REMOVE:
1614
break;
1615
1616
case AVAHI_BROWSER_ALL_FOR_NOW:
1617
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1618
if(debug){
1619
fprintf_plus(stderr, "No Mandos server found, still"
1620
" searching...\n");
1621
}
1622
break;
1623
}
1624
}
1625
1626
/* Signal handler that stops main loop after SIGTERM */
1627
static void handle_sigterm(int sig){
1628
if(quit_now){
1629
return;
1630
}
1631
quit_now = 1;
1632
signal_received = sig;
1633
int old_errno = errno;
1634
/* set main loop to exit */
1635
if(simple_poll != NULL){
1636
avahi_simple_poll_quit(simple_poll);
1637
}
1638
errno = old_errno;
1639
}
1640
1641
__attribute__((nonnull, warn_unused_result))
1642
bool get_flags(const char *ifname, struct ifreq *ifr){
1643
int ret;
1644
int old_errno;
1645
1646
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1647
if(s < 0){
1648
old_errno = errno;
1649
perror_plus("socket");
1650
errno = old_errno;
1651
return false;
1652
}
1653
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1654
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1655
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1656
if(ret == -1){
1657
if(debug){
1658
old_errno = errno;
1659
perror_plus("ioctl SIOCGIFFLAGS");
1660
errno = old_errno;
1661
}
1662
if((close(s) == -1) and debug){
1663
old_errno = errno;
1664
perror_plus("close");
1665
errno = old_errno;
1666
}
1667
return false;
1668
}
1669
if((close(s) == -1) and debug){
1670
old_errno = errno;
1671
perror_plus("close");
1672
errno = old_errno;
1673
}
1674
return true;
1675
}
1676
1677
__attribute__((nonnull, warn_unused_result))
1678
bool good_flags(const char *ifname, const struct ifreq *ifr){
1679
1680
/* Reject the loopback device */
1681
if(ifr->ifr_flags & IFF_LOOPBACK){
1682
if(debug){
1683
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1684
ifname);
1685
}
1686
return false;
1687
}
1688
/* Accept point-to-point devices only if connect_to is specified */
1689
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1690
if(debug){
1691
fprintf_plus(stderr, "Accepting point-to-point interface"
1692
" \"%s\"\n", ifname);
1693
}
1694
return true;
1695
}
1696
/* Otherwise, reject non-broadcast-capable devices */
1697
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1698
if(debug){
1699
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1700
" \"%s\"\n", ifname);
1701
}
1702
return false;
1703
}
1704
/* Reject non-ARP interfaces (including dummy interfaces) */
1705
if(ifr->ifr_flags & IFF_NOARP){
1706
if(debug){
1707
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1708
ifname);
1709
}
1710
return false;
1711
}
1712
1713
/* Accept this device */
1714
if(debug){
1715
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1716
}
1717
return true;
1718
}
1719
1720
/*
1721
* This function determines if a directory entry in /sys/class/net
1722
* corresponds to an acceptable network device.
1723
* (This function is passed to scandir(3) as a filter function.)
1724
*/
1725
__attribute__((nonnull, warn_unused_result))
1726
int good_interface(const struct dirent *if_entry){
1727
if(if_entry->d_name[0] == '.'){
1728
return 0;
1729
}
1730
1731
struct ifreq ifr;
1732
if(not get_flags(if_entry->d_name, &ifr)){
1733
if(debug){
1734
fprintf_plus(stderr, "Failed to get flags for interface "
1735
"\"%s\"\n", if_entry->d_name);
1736
}
1737
return 0;
1738
}
1739
1740
if(not good_flags(if_entry->d_name, &ifr)){
1741
return 0;
1742
}
1743
return 1;
1744
}
1745
1746
/*
1747
* This function determines if a network interface is up.
1748
*/
1749
__attribute__((nonnull, warn_unused_result))
1750
bool interface_is_up(const char *interface){
1751
struct ifreq ifr;
1752
if(not get_flags(interface, &ifr)){
1753
if(debug){
1754
fprintf_plus(stderr, "Failed to get flags for interface "
1755
"\"%s\"\n", interface);
1756
}
1757
return false;
1758
}
1759
1760
return (bool)(ifr.ifr_flags & IFF_UP);
1761
}
1762
1763
/*
1764
* This function determines if a network interface is running
1765
*/
1766
__attribute__((nonnull, warn_unused_result))
1767
bool interface_is_running(const char *interface){
1768
struct ifreq ifr;
1769
if(not get_flags(interface, &ifr)){
1770
if(debug){
1771
fprintf_plus(stderr, "Failed to get flags for interface "
1772
"\"%s\"\n", interface);
1773
}
1774
return false;
1775
}
1776
1777
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1778
}
1779
1780
__attribute__((nonnull, pure, warn_unused_result))
1781
int notdotentries(const struct dirent *direntry){
1782
/* Skip "." and ".." */
1783
if(direntry->d_name[0] == '.'
1784
and (direntry->d_name[1] == '\0'
1785
or (direntry->d_name[1] == '.'
1786
and direntry->d_name[2] == '\0'))){
1787
return 0;
1788
}
1789
return 1;
1790
}
1791
1792
/* Is this directory entry a runnable program? */
1793
__attribute__((nonnull, warn_unused_result))
1794
int runnable_hook(const struct dirent *direntry){
1795
int ret;
1796
size_t sret;
1797
struct stat st;
1798
1799
if((direntry->d_name)[0] == '\0'){
1800
/* Empty name? */
1801
return 0;
1802
}
1803
1804
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1805
"abcdefghijklmnopqrstuvwxyz"
1806
"0123456789"
1807
"_.-");
1808
if((direntry->d_name)[sret] != '\0'){
1809
/* Contains non-allowed characters */
1810
if(debug){
1811
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1812
direntry->d_name);
1813
}
1814
return 0;
1815
}
1816
1817
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1818
if(ret == -1){
1819
if(debug){
1820
perror_plus("Could not stat hook");
1821
}
1822
return 0;
1823
}
1824
if(not (S_ISREG(st.st_mode))){
1825
/* Not a regular file */
1826
if(debug){
1827
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1828
direntry->d_name);
1829
}
1830
return 0;
1831
}
1832
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1833
/* Not executable */
1834
if(debug){
1835
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1836
direntry->d_name);
1837
}
1838
return 0;
1839
}
1840
if(debug){
1841
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1842
direntry->d_name);
1843
}
1844
return 1;
1845
}
1846
1847
__attribute__((nonnull, warn_unused_result))
1848
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1849
mandos_context *mc){
1850
int ret;
1851
struct timespec now;
1852
struct timespec waited_time;
1853
intmax_t block_time;
1854
1855
while(true){
1856
if(mc->current_server == NULL){
1857
if(debug){
1858
fprintf_plus(stderr, "Wait until first server is found."
1859
" No timeout!\n");
1860
}
1861
ret = avahi_simple_poll_iterate(s, -1);
1862
} else {
1863
if(debug){
1864
fprintf_plus(stderr, "Check current_server if we should run"
1865
" it, or wait\n");
1866
}
1867
/* the current time */
1868
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1869
if(ret == -1){
1870
perror_plus("clock_gettime");
1871
return -1;
1872
}
1873
/* Calculating in ms how long time between now and server
1874
who we visted longest time ago. Now - last seen. */
1875
waited_time.tv_sec = (now.tv_sec
1876
- mc->current_server->last_seen.tv_sec);
1877
waited_time.tv_nsec = (now.tv_nsec
1878
- mc->current_server->last_seen.tv_nsec);
1879
/* total time is 10s/10,000ms.
1880
Converting to s from ms by dividing by 1,000,
1881
and ns to ms by dividing by 1,000,000. */
1882
block_time = ((retry_interval
1883
- ((intmax_t)waited_time.tv_sec * 1000))
1884
- ((intmax_t)waited_time.tv_nsec / 1000000));
1885
1886
if(debug){
1887
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1888
block_time);
1889
}
1890
1891
if(block_time <= 0){
1892
ret = start_mandos_communication(mc->current_server->ip,
1893
mc->current_server->port,
1894
mc->current_server->if_index,
1895
mc->current_server->af, mc);
1896
if(ret == 0){
1897
avahi_simple_poll_quit(s);
1898
return 0;
1899
}
1900
ret = clock_gettime(CLOCK_MONOTONIC,
1901
&mc->current_server->last_seen);
1902
if(ret == -1){
1903
perror_plus("clock_gettime");
1904
return -1;
1905
}
1906
mc->current_server = mc->current_server->next;
1907
block_time = 0; /* Call avahi to find new Mandos
1908
servers, but don't block */
1909
}
1910
1911
ret = avahi_simple_poll_iterate(s, (int)block_time);
1912
}
1913
if(ret != 0){
1914
if(ret > 0 or errno != EINTR){
1915
return (ret != 1) ? ret : 0;
1916
}
1917
}
1918
}
1919
}
1920
1921
__attribute__((nonnull))
1922
void run_network_hooks(const char *mode, const char *interface,
1923
const float delay){
1924
struct dirent **direntries = NULL;
1925
if(hookdir_fd == -1){
1926
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1927
| O_CLOEXEC);
1928
if(hookdir_fd == -1){
1929
if(errno == ENOENT){
1930
if(debug){
1931
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1932
" found\n", hookdir);
1933
}
1934
} else {
1935
perror_plus("open");
1936
}
1937
return;
1938
}
1939
}
1940
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1941
if(devnull == -1){
1942
perror_plus("open(\"/dev/null\", O_RDONLY)");
1943
return;
1944
}
1945
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1946
runnable_hook, alphasort);
1947
if(numhooks == -1){
1948
perror_plus("scandir");
1949
close(devnull);
1950
return;
1951
}
1952
struct dirent *direntry;
1953
int ret;
1954
for(int i = 0; i < numhooks; i++){
1955
direntry = direntries[i];
1956
if(debug){
1957
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1958
direntry->d_name);
1959
}
1960
pid_t hook_pid = fork();
1961
if(hook_pid == 0){
1962
/* Child */
1963
/* Raise privileges */
1964
errno = raise_privileges_permanently();
1965
if(errno != 0){
1966
perror_plus("Failed to raise privileges");
1967
_exit(EX_NOPERM);
1968
}
1969
/* Set group */
1970
errno = 0;
1971
ret = setgid(0);
1972
if(ret == -1){
1973
perror_plus("setgid");
1974
_exit(EX_NOPERM);
1975
}
1976
/* Reset supplementary groups */
1977
errno = 0;
1978
ret = setgroups(0, NULL);
1979
if(ret == -1){
1980
perror_plus("setgroups");
1981
_exit(EX_NOPERM);
1982
}
1983
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1984
if(ret == -1){
1985
perror_plus("setenv");
1986
_exit(EX_OSERR);
1987
}
1988
ret = setenv("DEVICE", interface, 1);
1989
if(ret == -1){
1990
perror_plus("setenv");
1991
_exit(EX_OSERR);
1992
}
1993
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1994
if(ret == -1){
1995
perror_plus("setenv");
1996
_exit(EX_OSERR);
1997
}
1998
ret = setenv("MODE", mode, 1);
1999
if(ret == -1){
2000
perror_plus("setenv");
2001
_exit(EX_OSERR);
2002
}
2003
char *delaystring;
2004
ret = asprintf(&delaystring, "%f", (double)delay);
2005
if(ret == -1){
2006
perror_plus("asprintf");
2007
_exit(EX_OSERR);
2008
}
2009
ret = setenv("DELAY", delaystring, 1);
2010
if(ret == -1){
2011
free(delaystring);
2012
perror_plus("setenv");
2013
_exit(EX_OSERR);
2014
}
2015
free(delaystring);
2016
if(connect_to != NULL){
2017
ret = setenv("CONNECT", connect_to, 1);
2018
if(ret == -1){
2019
perror_plus("setenv");
2020
_exit(EX_OSERR);
2021
}
2022
}
2023
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2024
direntry->d_name,
2025
O_RDONLY));
2026
if(hook_fd == -1){
2027
perror_plus("openat");
2028
_exit(EXIT_FAILURE);
2029
}
2030
if(close(hookdir_fd) == -1){
2031
perror_plus("close");
2032
_exit(EXIT_FAILURE);
2033
}
2034
ret = dup2(devnull, STDIN_FILENO);
2035
if(ret == -1){
2036
perror_plus("dup2(devnull, STDIN_FILENO)");
2037
_exit(EX_OSERR);
2038
}
2039
ret = close(devnull);
2040
if(ret == -1){
2041
perror_plus("close");
2042
_exit(EX_OSERR);
2043
}
2044
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2045
if(ret == -1){
2046
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2047
_exit(EX_OSERR);
2048
}
2049
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2050
environ) == -1){
2051
perror_plus("fexecve");
2052
_exit(EXIT_FAILURE);
2053
}
2054
} else {
2055
if(hook_pid == -1){
2056
perror_plus("fork");
2057
free(direntry);
2058
continue;
2059
}
2060
int status;
2061
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2062
perror_plus("waitpid");
2063
free(direntry);
2064
continue;
2065
}
2066
if(WIFEXITED(status)){
2067
if(WEXITSTATUS(status) != 0){
2068
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2069
" with status %d\n", direntry->d_name,
2070
WEXITSTATUS(status));
2071
free(direntry);
2072
continue;
2073
}
2074
} else if(WIFSIGNALED(status)){
2075
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2076
" signal %d\n", direntry->d_name,
2077
WTERMSIG(status));
2078
free(direntry);
2079
continue;
2080
} else {
2081
fprintf_plus(stderr, "Warning: network hook \"%s\""
2082
" crashed\n", direntry->d_name);
2083
free(direntry);
2084
continue;
2085
}
2086
}
2087
if(debug){
2088
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2089
direntry->d_name);
2090
}
2091
free(direntry);
2092
}
2093
free(direntries);
2094
if(close(hookdir_fd) == -1){
2095
perror_plus("close");
2096
} else {
2097
hookdir_fd = -1;
2098
}
2099
close(devnull);
2100
}
2101
2102
__attribute__((nonnull, warn_unused_result))
2103
int bring_up_interface(const char *const interface,
2104
const float delay){
2105
int old_errno = errno;
2106
int ret;
2107
struct ifreq network;
2108
unsigned int if_index = if_nametoindex(interface);
2109
if(if_index == 0){
2110
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2111
errno = old_errno;
2112
return ENXIO;
2113
}
2114
2115
if(quit_now){
2116
errno = old_errno;
2117
return EINTR;
2118
}
2119
2120
if(not interface_is_up(interface)){
2121
int ret_errno = 0;
2122
int ioctl_errno = 0;
2123
if(not get_flags(interface, &network)){
2124
ret_errno = errno;
2125
fprintf_plus(stderr, "Failed to get flags for interface "
2126
"\"%s\"\n", interface);
2127
errno = old_errno;
2128
return ret_errno;
2129
}
2130
network.ifr_flags |= IFF_UP; /* set flag */
2131
2132
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2133
if(sd == -1){
2134
ret_errno = errno;
2135
perror_plus("socket");
2136
errno = old_errno;
2137
return ret_errno;
2138
}
2139
2140
if(quit_now){
2141
ret = close(sd);
2142
if(ret == -1){
2143
perror_plus("close");
2144
}
2145
errno = old_errno;
2146
return EINTR;
2147
}
2148
2149
if(debug){
2150
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2151
interface);
2152
}
2153
2154
/* Raise privileges */
2155
ret_errno = raise_privileges();
2156
if(ret_errno != 0){
2157
errno = ret_errno;
2158
perror_plus("Failed to raise privileges");
2159
}
2160
2161
#ifdef __linux__
2162
int ret_linux;
2163
bool restore_loglevel = false;
2164
if(ret_errno == 0){
2165
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2166
messages about the network interface to mess up the prompt */
2167
ret_linux = klogctl(8, NULL, 5);
2168
if(ret_linux == -1){
2169
perror_plus("klogctl");
2170
} else {
2171
restore_loglevel = true;
2172
}
2173
}
2174
#endif /* __linux__ */
2175
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2176
ioctl_errno = errno;
2177
#ifdef __linux__
2178
if(restore_loglevel){
2179
ret_linux = klogctl(7, NULL, 0);
2180
if(ret_linux == -1){
2181
perror_plus("klogctl");
2182
}
2183
}
2184
#endif /* __linux__ */
2185
2186
/* If raise_privileges() succeeded above */
2187
if(ret_errno == 0){
2188
/* Lower privileges */
2189
ret_errno = lower_privileges();
2190
if(ret_errno != 0){
2191
errno = ret_errno;
2192
perror_plus("Failed to lower privileges");
2193
}
2194
}
2195
2196
/* Close the socket */
2197
ret = close(sd);
2198
if(ret == -1){
2199
perror_plus("close");
2200
}
2201
2202
if(ret_setflags == -1){
2203
errno = ioctl_errno;
2204
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2205
errno = old_errno;
2206
return ioctl_errno;
2207
}
2208
} else if(debug){
2209
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2210
interface);
2211
}
2212
2213
/* Sleep checking until interface is running.
2214
Check every 0.25s, up to total time of delay */
2215
for(int i = 0; i < delay * 4; i++){
2216
if(interface_is_running(interface)){
2217
break;
2218
}
2219
struct timespec sleeptime = { .tv_nsec = 250000000 };
2220
ret = nanosleep(&sleeptime, NULL);
2221
if(ret == -1 and errno != EINTR){
2222
perror_plus("nanosleep");
2223
}
2224
}
2225
2226
errno = old_errno;
2227
return 0;
2228
}
2229
2230
__attribute__((nonnull, warn_unused_result))
2231
int take_down_interface(const char *const interface){
2232
int old_errno = errno;
2233
struct ifreq network;
2234
unsigned int if_index = if_nametoindex(interface);
2235
if(if_index == 0){
2236
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2237
errno = old_errno;
2238
return ENXIO;
2239
}
2240
if(interface_is_up(interface)){
2241
int ret_errno = 0;
2242
int ioctl_errno = 0;
2243
if(not get_flags(interface, &network) and debug){
2244
ret_errno = errno;
2245
fprintf_plus(stderr, "Failed to get flags for interface "
2246
"\"%s\"\n", interface);
2247
errno = old_errno;
2248
return ret_errno;
2249
}
2250
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2251
2252
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2253
if(sd == -1){
2254
ret_errno = errno;
2255
perror_plus("socket");
2256
errno = old_errno;
2257
return ret_errno;
2258
}
2259
2260
if(debug){
2261
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2262
interface);
2263
}
2264
2265
/* Raise privileges */
2266
ret_errno = raise_privileges();
2267
if(ret_errno != 0){
2268
errno = ret_errno;
2269
perror_plus("Failed to raise privileges");
2270
}
2271
2272
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2273
ioctl_errno = errno;
2274
2275
/* If raise_privileges() succeeded above */
2276
if(ret_errno == 0){
2277
/* Lower privileges */
2278
ret_errno = lower_privileges();
2279
if(ret_errno != 0){
2280
errno = ret_errno;
2281
perror_plus("Failed to lower privileges");
2282
}
2283
}
2284
2285
/* Close the socket */
2286
int ret = close(sd);
2287
if(ret == -1){
2288
perror_plus("close");
2289
}
2290
2291
if(ret_setflags == -1){
2292
errno = ioctl_errno;
2293
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2294
errno = old_errno;
2295
return ioctl_errno;
2296
}
2297
} else if(debug){
2298
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2299
interface);
2300
}
2301
2302
errno = old_errno;
2303
return 0;
2304
}
2305
2306
int main(int argc, char *argv[]){
2307
mandos_context mc = { .server = NULL, .dh_bits = 0,
2308
.priority = "SECURE256:!CTYPE-X.509"
2309
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2310
.current_server = NULL, .interfaces = NULL,
2311
.interfaces_size = 0 };
2312
AvahiSServiceBrowser *sb = NULL;
2313
error_t ret_errno;
2314
int ret;
2315
intmax_t tmpmax;
2316
char *tmp;
2317
int exitcode = EXIT_SUCCESS;
2318
char *interfaces_to_take_down = NULL;
2319
size_t interfaces_to_take_down_size = 0;
2320
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2321
char old_tempdir[] = "/tmp/mandosXXXXXX";
2322
char *tempdir = NULL;
2323
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2324
const char *seckey = PATHDIR "/" SECKEY;
2325
const char *pubkey = PATHDIR "/" PUBKEY;
2326
const char *dh_params_file = NULL;
2327
char *interfaces_hooks = NULL;
2328
2329
bool gnutls_initialized = false;
2330
bool gpgme_initialized = false;
2331
float delay = 2.5f;
2332
double retry_interval = 10; /* 10s between trying a server and
2333
retrying the same server again */
2334
2335
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2336
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2337
2338
uid = getuid();
2339
gid = getgid();
2340
2341
/* Lower any group privileges we might have, just to be safe */
2342
errno = 0;
2343
ret = setgid(gid);
2344
if(ret == -1){
2345
perror_plus("setgid");
2346
}
2347
2348
/* Lower user privileges (temporarily) */
2349
errno = 0;
2350
ret = seteuid(uid);
2351
if(ret == -1){
2352
perror_plus("seteuid");
2353
}
2354
2355
if(quit_now){
2356
goto end;
2357
}
2358
2359
{
2360
struct argp_option options[] = {
2361
{ .name = "debug", .key = 128,
2362
.doc = "Debug mode", .group = 3 },
2363
{ .name = "connect", .key = 'c',
2364
.arg = "ADDRESS:PORT",
2365
.doc = "Connect directly to a specific Mandos server",
2366
.group = 1 },
2367
{ .name = "interface", .key = 'i',
2368
.arg = "NAME",
2369
.doc = "Network interface that will be used to search for"
2370
" Mandos servers",
2371
.group = 1 },
2372
{ .name = "seckey", .key = 's',
2373
.arg = "FILE",
2374
.doc = "OpenPGP secret key file base name",
2375
.group = 1 },
2376
{ .name = "pubkey", .key = 'p',
2377
.arg = "FILE",
2378
.doc = "OpenPGP public key file base name",
2379
.group = 2 },
2380
{ .name = "dh-bits", .key = 129,
2381
.arg = "BITS",
2382
.doc = "Bit length of the prime number used in the"
2383
" Diffie-Hellman key exchange",
2384
.group = 2 },
2385
{ .name = "dh-params", .key = 134,
2386
.arg = "FILE",
2387
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2388
" for the Diffie-Hellman key exchange",
2389
.group = 2 },
2390
{ .name = "priority", .key = 130,
2391
.arg = "STRING",
2392
.doc = "GnuTLS priority string for the TLS handshake",
2393
.group = 1 },
2394
{ .name = "delay", .key = 131,
2395
.arg = "SECONDS",
2396
.doc = "Maximum delay to wait for interface startup",
2397
.group = 2 },
2398
{ .name = "retry", .key = 132,
2399
.arg = "SECONDS",
2400
.doc = "Retry interval used when denied by the Mandos server",
2401
.group = 2 },
2402
{ .name = "network-hook-dir", .key = 133,
2403
.arg = "DIR",
2404
.doc = "Directory where network hooks are located",
2405
.group = 2 },
2406
/*
2407
* These reproduce what we would get without ARGP_NO_HELP
2408
*/
2409
{ .name = "help", .key = '?',
2410
.doc = "Give this help list", .group = -1 },
2411
{ .name = "usage", .key = -3,
2412
.doc = "Give a short usage message", .group = -1 },
2413
{ .name = "version", .key = 'V',
2414
.doc = "Print program version", .group = -1 },
2415
{ .name = NULL }
2416
};
2417
2418
error_t parse_opt(int key, char *arg,
2419
struct argp_state *state){
2420
errno = 0;
2421
switch(key){
2422
case 128: /* --debug */
2423
debug = true;
2424
break;
2425
case 'c': /* --connect */
2426
connect_to = arg;
2427
break;
2428
case 'i': /* --interface */
2429
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2430
arg, (int)',');
2431
if(ret_errno != 0){
2432
argp_error(state, "%s", strerror(ret_errno));
2433
}
2434
break;
2435
case 's': /* --seckey */
2436
seckey = arg;
2437
break;
2438
case 'p': /* --pubkey */
2439
pubkey = arg;
2440
break;
2441
case 129: /* --dh-bits */
2442
errno = 0;
2443
tmpmax = strtoimax(arg, &tmp, 10);
2444
if(errno != 0 or tmp == arg or *tmp != '\0'
2445
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2446
argp_error(state, "Bad number of DH bits");
2447
}
2448
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2449
break;
2450
case 134: /* --dh-params */
2451
dh_params_file = arg;
2452
break;
2453
case 130: /* --priority */
2454
mc.priority = arg;
2455
break;
2456
case 131: /* --delay */
2457
errno = 0;
2458
delay = strtof(arg, &tmp);
2459
if(errno != 0 or tmp == arg or *tmp != '\0'){
2460
argp_error(state, "Bad delay");
2461
}
2462
case 132: /* --retry */
2463
errno = 0;
2464
retry_interval = strtod(arg, &tmp);
2465
if(errno != 0 or tmp == arg or *tmp != '\0'
2466
or (retry_interval * 1000) > INT_MAX
2467
or retry_interval < 0){
2468
argp_error(state, "Bad retry interval");
2469
}
2470
break;
2471
case 133: /* --network-hook-dir */
2472
hookdir = arg;
2473
break;
2474
/*
2475
* These reproduce what we would get without ARGP_NO_HELP
2476
*/
2477
case '?': /* --help */
2478
argp_state_help(state, state->out_stream,
2479
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2480
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2481
case -3: /* --usage */
2482
argp_state_help(state, state->out_stream,
2483
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2484
case 'V': /* --version */
2485
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2486
exit(argp_err_exit_status);
2487
break;
2488
default:
2489
return ARGP_ERR_UNKNOWN;
2490
}
2491
return errno;
2492
}
2493
2494
struct argp argp = { .options = options, .parser = parse_opt,
2495
.args_doc = "",
2496
.doc = "Mandos client -- Get and decrypt"
2497
" passwords from a Mandos server" };
2498
ret_errno = argp_parse(&argp, argc, argv,
2499
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2500
switch(ret_errno){
2501
case 0:
2502
break;
2503
case ENOMEM:
2504
default:
2505
errno = ret_errno;
2506
perror_plus("argp_parse");
2507
exitcode = EX_OSERR;
2508
goto end;
2509
case EINVAL:
2510
exitcode = EX_USAGE;
2511
goto end;
2512
}
2513
}
2514
2515
{
2516
/* Work around Debian bug #633582:
2517
<https://bugs.debian.org/633582> */
2518
2519
/* Re-raise privileges */
2520
ret = raise_privileges();
2521
if(ret != 0){
2522
errno = ret;
2523
perror_plus("Failed to raise privileges");
2524
} else {
2525
struct stat st;
2526
2527
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2528
int seckey_fd = open(seckey, O_RDONLY);
2529
if(seckey_fd == -1){
2530
perror_plus("open");
2531
} else {
2532
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2533
if(ret == -1){
2534
perror_plus("fstat");
2535
} else {
2536
if(S_ISREG(st.st_mode)
2537
and st.st_uid == 0 and st.st_gid == 0){
2538
ret = fchown(seckey_fd, uid, gid);
2539
if(ret == -1){
2540
perror_plus("fchown");
2541
}
2542
}
2543
}
2544
close(seckey_fd);
2545
}
2546
}
2547
2548
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2549
int pubkey_fd = open(pubkey, O_RDONLY);
2550
if(pubkey_fd == -1){
2551
perror_plus("open");
2552
} else {
2553
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2554
if(ret == -1){
2555
perror_plus("fstat");
2556
} else {
2557
if(S_ISREG(st.st_mode)
2558
and st.st_uid == 0 and st.st_gid == 0){
2559
ret = fchown(pubkey_fd, uid, gid);
2560
if(ret == -1){
2561
perror_plus("fchown");
2562
}
2563
}
2564
}
2565
close(pubkey_fd);
2566
}
2567
}
2568
2569
if(dh_params_file != NULL
2570
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2571
int dhparams_fd = open(dh_params_file, O_RDONLY);
2572
if(dhparams_fd == -1){
2573
perror_plus("open");
2574
} else {
2575
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2576
if(ret == -1){
2577
perror_plus("fstat");
2578
} else {
2579
if(S_ISREG(st.st_mode)
2580
and st.st_uid == 0 and st.st_gid == 0){
2581
ret = fchown(dhparams_fd, uid, gid);
2582
if(ret == -1){
2583
perror_plus("fchown");
2584
}
2585
}
2586
}
2587
close(dhparams_fd);
2588
}
2589
}
2590
2591
/* Lower privileges */
2592
ret = lower_privileges();
2593
if(ret != 0){
2594
errno = ret;
2595
perror_plus("Failed to lower privileges");
2596
}
2597
}
2598
}
2599
2600
/* Remove invalid interface names (except "none") */
2601
{
2602
char *interface = NULL;
2603
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2604
interface))){
2605
if(strcmp(interface, "none") != 0
2606
and if_nametoindex(interface) == 0){
2607
if(interface[0] != '\0'){
2608
fprintf_plus(stderr, "Not using nonexisting interface"
2609
" \"%s\"\n", interface);
2610
}
2611
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2612
interface = NULL;
2613
}
2614
}
2615
}
2616
2617
/* Run network hooks */
2618
{
2619
if(mc.interfaces != NULL){
2620
interfaces_hooks = malloc(mc.interfaces_size);
2621
if(interfaces_hooks == NULL){
2622
perror_plus("malloc");
2623
goto end;
2624
}
2625
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2626
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2627
}
2628
run_network_hooks("start", interfaces_hooks != NULL ?
2629
interfaces_hooks : "", delay);
2630
}
2631
2632
if(not debug){
2633
avahi_set_log_function(empty_log);
2634
}
2635
2636
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2637
from the signal handler */
2638
/* Initialize the pseudo-RNG for Avahi */
2639
srand((unsigned int) time(NULL));
2640
simple_poll = avahi_simple_poll_new();
2641
if(simple_poll == NULL){
2642
fprintf_plus(stderr,
2643
"Avahi: Failed to create simple poll object.\n");
2644
exitcode = EX_UNAVAILABLE;
2645
goto end;
2646
}
2647
2648
sigemptyset(&sigterm_action.sa_mask);
2649
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2650
if(ret == -1){
2651
perror_plus("sigaddset");
2652
exitcode = EX_OSERR;
2653
goto end;
2654
}
2655
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2656
if(ret == -1){
2657
perror_plus("sigaddset");
2658
exitcode = EX_OSERR;
2659
goto end;
2660
}
2661
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2662
if(ret == -1){
2663
perror_plus("sigaddset");
2664
exitcode = EX_OSERR;
2665
goto end;
2666
}
2667
/* Need to check if the handler is SIG_IGN before handling:
2668
| [[info:libc:Initial Signal Actions]] |
2669
| [[info:libc:Basic Signal Handling]] |
2670
*/
2671
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2672
if(ret == -1){
2673
perror_plus("sigaction");
2674
return EX_OSERR;
2675
}
2676
if(old_sigterm_action.sa_handler != SIG_IGN){
2677
ret = sigaction(SIGINT, &sigterm_action, NULL);
2678
if(ret == -1){
2679
perror_plus("sigaction");
2680
exitcode = EX_OSERR;
2681
goto end;
2682
}
2683
}
2684
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2685
if(ret == -1){
2686
perror_plus("sigaction");
2687
return EX_OSERR;
2688
}
2689
if(old_sigterm_action.sa_handler != SIG_IGN){
2690
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2691
if(ret == -1){
2692
perror_plus("sigaction");
2693
exitcode = EX_OSERR;
2694
goto end;
2695
}
2696
}
2697
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2698
if(ret == -1){
2699
perror_plus("sigaction");
2700
return EX_OSERR;
2701
}
2702
if(old_sigterm_action.sa_handler != SIG_IGN){
2703
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2704
if(ret == -1){
2705
perror_plus("sigaction");
2706
exitcode = EX_OSERR;
2707
goto end;
2708
}
2709
}
2710
2711
/* If no interfaces were specified, make a list */
2712
if(mc.interfaces == NULL){
2713
struct dirent **direntries = NULL;
2714
/* Look for any good interfaces */
2715
ret = scandir(sys_class_net, &direntries, good_interface,
2716
alphasort);
2717
if(ret >= 1){
2718
/* Add all found interfaces to interfaces list */
2719
for(int i = 0; i < ret; ++i){
2720
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2721
direntries[i]->d_name);
2722
if(ret_errno != 0){
2723
errno = ret_errno;
2724
perror_plus("argz_add");
2725
free(direntries[i]);
2726
continue;
2727
}
2728
if(debug){
2729
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2730
direntries[i]->d_name);
2731
}
2732
free(direntries[i]);
2733
}
2734
free(direntries);
2735
} else {
2736
if(ret == 0){
2737
free(direntries);
2738
}
2739
fprintf_plus(stderr, "Could not find a network interface\n");
2740
exitcode = EXIT_FAILURE;
2741
goto end;
2742
}
2743
}
2744
2745
/* Bring up interfaces which are down, and remove any "none"s */
2746
{
2747
char *interface = NULL;
2748
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2749
interface))){
2750
/* If interface name is "none", stop bringing up interfaces.
2751
Also remove all instances of "none" from the list */
2752
if(strcmp(interface, "none") == 0){
2753
argz_delete(&mc.interfaces, &mc.interfaces_size,
2754
interface);
2755
interface = NULL;
2756
while((interface = argz_next(mc.interfaces,
2757
mc.interfaces_size, interface))){
2758
if(strcmp(interface, "none") == 0){
2759
argz_delete(&mc.interfaces, &mc.interfaces_size,
2760
interface);
2761
interface = NULL;
2762
}
2763
}
2764
break;
2765
}
2766
bool interface_was_up = interface_is_up(interface);
2767
errno = bring_up_interface(interface, delay);
2768
if(not interface_was_up){
2769
if(errno != 0){
2770
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2771
" %s\n", interface, strerror(errno));
2772
} else {
2773
errno = argz_add(&interfaces_to_take_down,
2774
&interfaces_to_take_down_size,
2775
interface);
2776
if(errno != 0){
2777
perror_plus("argz_add");
2778
}
2779
}
2780
}
2781
}
2782
if(debug and (interfaces_to_take_down == NULL)){
2783
fprintf_plus(stderr, "No interfaces were brought up\n");
2784
}
2785
}
2786
2787
/* If we only got one interface, explicitly use only that one */
2788
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2789
if(debug){
2790
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2791
mc.interfaces);
2792
}
2793
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2794
}
2795
2796
if(quit_now){
2797
goto end;
2798
}
2799
2800
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2801
if(ret == -1){
2802
fprintf_plus(stderr, "init_gnutls_global failed\n");
2803
exitcode = EX_UNAVAILABLE;
2804
goto end;
2805
} else {
2806
gnutls_initialized = true;
2807
}
2808
2809
if(quit_now){
2810
goto end;
2811
}
2812
2813
/* Try /run/tmp before /tmp */
2814
tempdir = mkdtemp(run_tempdir);
2815
if(tempdir == NULL and errno == ENOENT){
2816
if(debug){
2817
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2818
run_tempdir, old_tempdir);
2819
}
2820
tempdir = mkdtemp(old_tempdir);
2821
}
2822
if(tempdir == NULL){
2823
perror_plus("mkdtemp");
2824
goto end;
2825
}
2826
2827
if(quit_now){
2828
goto end;
2829
}
2830
2831
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2832
fprintf_plus(stderr, "init_gpgme failed\n");
2833
exitcode = EX_UNAVAILABLE;
2834
goto end;
2835
} else {
2836
gpgme_initialized = true;
2837
}
2838
2839
if(quit_now){
2840
goto end;
2841
}
2842
2843
if(connect_to != NULL){
2844
/* Connect directly, do not use Zeroconf */
2845
/* (Mainly meant for debugging) */
2846
char *address = strrchr(connect_to, ':');
2847
2848
if(address == NULL){
2849
fprintf_plus(stderr, "No colon in address\n");
2850
exitcode = EX_USAGE;
2851
goto end;
2852
}
2853
2854
if(quit_now){
2855
goto end;
2856
}
2857
2858
in_port_t port;
2859
errno = 0;
2860
tmpmax = strtoimax(address+1, &tmp, 10);
2861
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2862
or tmpmax != (in_port_t)tmpmax){
2863
fprintf_plus(stderr, "Bad port number\n");
2864
exitcode = EX_USAGE;
2865
goto end;
2866
}
2867
2868
if(quit_now){
2869
goto end;
2870
}
2871
2872
port = (in_port_t)tmpmax;
2873
*address = '\0';
2874
/* Colon in address indicates IPv6 */
2875
int af;
2876
if(strchr(connect_to, ':') != NULL){
2877
af = AF_INET6;
2878
/* Accept [] around IPv6 address - see RFC 5952 */
2879
if(connect_to[0] == '[' and address[-1] == ']')
2880
{
2881
connect_to++;
2882
address[-1] = '\0';
2883
}
2884
} else {
2885
af = AF_INET;
2886
}
2887
address = connect_to;
2888
2889
if(quit_now){
2890
goto end;
2891
}
2892
2893
while(not quit_now){
2894
ret = start_mandos_communication(address, port, if_index, af,
2895
&mc);
2896
if(quit_now or ret == 0){
2897
break;
2898
}
2899
if(debug){
2900
fprintf_plus(stderr, "Retrying in %d seconds\n",
2901
(int)retry_interval);
2902
}
2903
sleep((unsigned int)retry_interval);
2904
}
2905
2906
if(not quit_now){
2907
exitcode = EXIT_SUCCESS;
2908
}
2909
2910
goto end;
2911
}
2912
2913
if(quit_now){
2914
goto end;
2915
}
2916
2917
{
2918
AvahiServerConfig config;
2919
/* Do not publish any local Zeroconf records */
2920
avahi_server_config_init(&config);
2921
config.publish_hinfo = 0;
2922
config.publish_addresses = 0;
2923
config.publish_workstation = 0;
2924
config.publish_domain = 0;
2925
2926
/* Allocate a new server */
2927
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2928
&config, NULL, NULL, &ret);
2929
2930
/* Free the Avahi configuration data */
2931
avahi_server_config_free(&config);
2932
}
2933
2934
/* Check if creating the Avahi server object succeeded */
2935
if(mc.server == NULL){
2936
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2937
avahi_strerror(ret));
2938
exitcode = EX_UNAVAILABLE;
2939
goto end;
2940
}
2941
2942
if(quit_now){
2943
goto end;
2944
}
2945
2946
/* Create the Avahi service browser */
2947
sb = avahi_s_service_browser_new(mc.server, if_index,
2948
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2949
NULL, 0, browse_callback,
2950
(void *)&mc);
2951
if(sb == NULL){
2952
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2953
avahi_strerror(avahi_server_errno(mc.server)));
2954
exitcode = EX_UNAVAILABLE;
2955
goto end;
2956
}
2957
2958
if(quit_now){
2959
goto end;
2960
}
2961
2962
/* Run the main loop */
2963
2964
if(debug){
2965
fprintf_plus(stderr, "Starting Avahi loop search\n");
2966
}
2967
2968
ret = avahi_loop_with_timeout(simple_poll,
2969
(int)(retry_interval * 1000), &mc);
2970
if(debug){
2971
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2972
(ret == 0) ? "successfully" : "with error");
2973
}
2974
2975
end:
2976
2977
if(debug){
2978
if(signal_received){
2979
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
2980
argv[0], signal_received,
2981
strsignal(signal_received));
2982
} else {
2983
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2984
}
2985
}
2986
2987
/* Cleanup things */
2988
free(mc.interfaces);
2989
2990
if(sb != NULL)
2991
avahi_s_service_browser_free(sb);
2992
2993
if(mc.server != NULL)
2994
avahi_server_free(mc.server);
2995
2996
if(simple_poll != NULL)
2997
avahi_simple_poll_free(simple_poll);
2998
2999
if(gnutls_initialized){
3000
gnutls_certificate_free_credentials(mc.cred);
3001
gnutls_dh_params_deinit(mc.dh_params);
3002
}
3003
3004
if(gpgme_initialized){
3005
gpgme_release(mc.ctx);
3006
}
3007
3008
/* Cleans up the circular linked list of Mandos servers the client
3009
has seen */
3010
if(mc.current_server != NULL){
3011
mc.current_server->prev->next = NULL;
3012
while(mc.current_server != NULL){
3013
server *next = mc.current_server->next;
3014
#ifdef __GNUC__
3015
#pragma GCC diagnostic push
3016
#pragma GCC diagnostic ignored "-Wcast-qual"
3017
#endif
3018
free((char *)(mc.current_server->ip));
3019
#ifdef __GNUC__
3020
#pragma GCC diagnostic pop
3021
#endif
3022
free(mc.current_server);
3023
mc.current_server = next;
3024
}
3025
}
3026
3027
/* Re-raise privileges */
3028
{
3029
ret = raise_privileges();
3030
if(ret != 0){
3031
errno = ret;
3032
perror_plus("Failed to raise privileges");
3033
} else {
3034
3035
/* Run network hooks */
3036
run_network_hooks("stop", interfaces_hooks != NULL ?
3037
interfaces_hooks : "", delay);
3038
3039
/* Take down the network interfaces which were brought up */
3040
{
3041
char *interface = NULL;
3042
while((interface = argz_next(interfaces_to_take_down,
3043
interfaces_to_take_down_size,
3044
interface))){
3045
ret = take_down_interface(interface);
3046
if(ret != 0){
3047
errno = ret;
3048
perror_plus("Failed to take down interface");
3049
}
3050
}
3051
if(debug and (interfaces_to_take_down == NULL)){
3052
fprintf_plus(stderr, "No interfaces needed to be taken"
3053
" down\n");
3054
}
3055
}
3056
}
3057
3058
ret = lower_privileges_permanently();
3059
if(ret != 0){
3060
errno = ret;
3061
perror_plus("Failed to lower privileges permanently");
3062
}
3063
}
3064
3065
free(interfaces_to_take_down);
3066
free(interfaces_hooks);
3067
3068
void clean_dir_at(int base, const char * const dirname,
3069
uintmax_t level){
3070
struct dirent **direntries = NULL;
3071
int dret;
3072
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3073
O_RDONLY
3074
| O_NOFOLLOW
3075
| O_DIRECTORY
3076
| O_PATH));
3077
if(dir_fd == -1){
3078
perror_plus("open");
3079
return;
3080
}
3081
int numentries = scandirat(dir_fd, ".", &direntries,
3082
notdotentries, alphasort);
3083
if(numentries >= 0){
3084
for(int i = 0; i < numentries; i++){
3085
if(debug){
3086
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3087
dirname, direntries[i]->d_name);
3088
}
3089
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3090
if(dret == -1){
3091
if(errno == EISDIR){
3092
dret = unlinkat(dir_fd, direntries[i]->d_name,
3093
AT_REMOVEDIR);
3094
}
3095
if((dret == -1) and (errno == ENOTEMPTY)
3096
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3097
== 0) and (level == 0)){
3098
/* Recurse only in this special case */
3099
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3100
dret = 0;
3101
}
3102
if((dret == -1) and (errno != ENOENT)){
3103
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3104
direntries[i]->d_name, strerror(errno));
3105
}
3106
}
3107
free(direntries[i]);
3108
}
3109
3110
/* need to clean even if 0 because man page doesn't specify */
3111
free(direntries);
3112
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3113
if(dret == -1 and errno != ENOENT){
3114
perror_plus("rmdir");
3115
}
3116
} else {
3117
perror_plus("scandirat");
3118
}
3119
close(dir_fd);
3120
}
3121
3122
/* Removes the GPGME temp directory and all files inside */
3123
if(tempdir != NULL){
3124
clean_dir_at(-1, tempdir, 0);
3125
}
3126
3127
if(quit_now){
3128
sigemptyset(&old_sigterm_action.sa_mask);
3129
old_sigterm_action.sa_handler = SIG_DFL;
3130
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3131
&old_sigterm_action,
3132
NULL));
3133
if(ret == -1){
3134
perror_plus("sigaction");
3135
}
3136
do {
3137
ret = raise(signal_received);
3138
} while(ret != 0 and errno == EINTR);
3139
if(ret != 0){
3140
perror_plus("raise");
3141
abort();
3142
}
3143
TEMP_FAILURE_RETRY(pause());
3144
}
3145
3146
return exitcode;
3147
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0