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- Committer: Teddy Hogeborn
- Date: 2019-04-09 19:41:53 UTC
- mfrom: (237.7.647 trunk)
- Revision ID: teddy@recompile.se-20190409194153-khftfvj3ee27md1a
Merge from trunk
- files added:
- DBUS-API
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- files removed:
- initramfs-tools-hook-conf
- files modified:
- .bzrignore
added
removed
plugins.d/mandos-client.c
9
9
* "browse_callback", and parts of "main".
10
10
*
11
11
* Everything else is
12
* Copyright © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
14
*
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
19
*
20
* This program is distributed in the hope that it will be useful, but
12
* Copyright © 2008-2019 Teddy Hogeborn
13
* Copyright © 2008-2019 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
21
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
25
* General Public License for more details.
24
26
*
25
27
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
28
29
*
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
* Contact the authors at <mandos@recompile.se>.
30
31
*/
31
32
32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
34
#ifndef _LARGEFILE_SOURCE
33
35
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
37
#ifndef _FILE_OFFSET_BITS
34
38
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
35
40
36
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
37
42
38
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
40
remove() */
41
#include <stdint.h> /* uint16_t, uint32_t */
44
stdout, ferror() */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
42
46
#include <stddef.h> /* NULL, size_t, ssize_t */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
44
srand() */
45
#include <stdbool.h> /* bool, true */
46
#include <string.h> /* memset(), strcmp(), strlen(),
47
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
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 */
49
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
55
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
53
DIR */
54
#include <sys/stat.h> /* open() */
56
SOCK_STREAM, uid_t, gid_t, open(),
57
opendir(), DIR */
58
#include <sys/stat.h> /* open(), S_ISREG */
55
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
57
connect() */
58
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
61
getnameinfo() */
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
59
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
60
64
*/
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* time() */
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() */
65
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
75
SIOCSIFFLAGS, if_indextoname(),
67
76
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
77
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
78
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
79
*/
69
80
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
getuid(), getgid(), setuid(),
71
setgid() */
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
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 */
74
86
#include <argp.h> /* struct argp_option, error_t, struct
75
87
argp_state, struct argp,
76
88
argp_parse(), ARGP_KEY_ARG,
77
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__ */
78
108
79
109
/* Avahi */
80
110
/* All Avahi types, constants and functions
93
123
gnutls_*
94
124
init_gnutls_session(),
95
125
GNUTLS_* */
126
#if GNUTLS_VERSION_NUMBER < 0x030600
96
127
#include <gnutls/openpgp.h>
97
/* gnutls_certificate_set_openpgp_key_file(),
98
GNUTLS_OPENPGP_FMT_BASE64 */
128
/* gnutls_certificate_set_openpgp_key_file(),
129
GNUTLS_OPENPGP_FMT_BASE64 */
130
#elif GNUTLS_VERSION_NUMBER >= 0x030606
131
#include <gnutls/x509.h> /* gnutls_pkcs_encrypt_flags_t,
132
GNUTLS_PKCS_PLAIN,
133
GNUTLS_PKCS_NULL_PASSWORD */
134
#endif
99
135
100
136
/* GPGME */
101
137
#include <gpgme.h> /* All GPGME types, constants and
109
145
#define PATHDIR "/conf/conf.d/mandos"
110
146
#define SECKEY "seckey.txt"
111
147
#define PUBKEY "pubkey.txt"
148
#define TLS_PRIVKEY "tls-privkey.pem"
149
#define TLS_PUBKEY "tls-pubkey.pem"
150
#define HOOKDIR "/lib/mandos/network-hooks.d"
112
151
113
152
bool debug = false;
114
153
static const char mandos_protocol_version[] = "1";
115
154
const char *argp_program_version = "mandos-client " VERSION;
116
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
155
const char *argp_program_bug_address = "<mandos@recompile.se>";
156
static const char sys_class_net[] = "/sys/class/net";
157
char *connect_to = NULL;
158
const char *hookdir = HOOKDIR;
159
int hookdir_fd = -1;
160
uid_t uid = 65534;
161
gid_t gid = 65534;
162
163
/* Doubly linked list that need to be circularly linked when used */
164
typedef struct server{
165
const char *ip;
166
in_port_t port;
167
AvahiIfIndex if_index;
168
int af;
169
struct timespec last_seen;
170
struct server *next;
171
struct server *prev;
172
} server;
117
173
118
174
/* Used for passing in values through the Avahi callback functions */
119
175
typedef struct {
120
AvahiSimplePoll *simple_poll;
121
176
AvahiServer *server;
122
177
gnutls_certificate_credentials_t cred;
123
178
unsigned int dh_bits;
124
179
gnutls_dh_params_t dh_params;
125
180
const char *priority;
126
181
gpgme_ctx_t ctx;
182
server *current_server;
183
char *interfaces;
184
size_t interfaces_size;
127
185
} mandos_context;
128
186
187
/* global so signal handler can reach it*/
188
AvahiSimplePoll *simple_poll;
189
190
sig_atomic_t quit_now = 0;
191
int signal_received = 0;
192
193
/* Function to use when printing errors */
194
void perror_plus(const char *print_text){
195
int e = errno;
196
fprintf(stderr, "Mandos plugin %s: ",
197
program_invocation_short_name);
198
errno = e;
199
perror(print_text);
200
}
201
202
__attribute__((format (gnu_printf, 2, 3), nonnull))
203
int fprintf_plus(FILE *stream, const char *format, ...){
204
va_list ap;
205
va_start (ap, format);
206
207
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
208
program_invocation_short_name));
209
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
210
}
211
129
212
/*
130
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
131
* "buffer_capacity" is how much is currently allocated,
213
* Make additional room in "buffer" for at least BUFFER_SIZE more
214
* bytes. "buffer_capacity" is how much is currently allocated,
132
215
* "buffer_length" is how much is already used.
133
216
*/
134
size_t adjustbuffer(char **buffer, size_t buffer_length,
135
size_t buffer_capacity){
217
__attribute__((nonnull, warn_unused_result))
218
size_t incbuffer(char **buffer, size_t buffer_length,
219
size_t buffer_capacity){
136
220
if(buffer_length + BUFFER_SIZE > buffer_capacity){
137
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
138
if(buffer == NULL){
221
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
222
if(new_buf == NULL){
223
int old_errno = errno;
224
free(*buffer);
225
errno = old_errno;
226
*buffer = NULL;
139
227
return 0;
140
228
}
229
*buffer = new_buf;
141
230
buffer_capacity += BUFFER_SIZE;
142
231
}
143
232
return buffer_capacity;
144
233
}
145
234
235
/* Add server to set of servers to retry periodically */
236
__attribute__((nonnull, warn_unused_result))
237
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
238
int af, server **current_server){
239
int ret;
240
server *new_server = malloc(sizeof(server));
241
if(new_server == NULL){
242
perror_plus("malloc");
243
return false;
244
}
245
*new_server = (server){ .ip = strdup(ip),
246
.port = port,
247
.if_index = if_index,
248
.af = af };
249
if(new_server->ip == NULL){
250
perror_plus("strdup");
251
free(new_server);
252
return false;
253
}
254
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
255
if(ret == -1){
256
perror_plus("clock_gettime");
257
#ifdef __GNUC__
258
#pragma GCC diagnostic push
259
#pragma GCC diagnostic ignored "-Wcast-qual"
260
#endif
261
free((char *)(new_server->ip));
262
#ifdef __GNUC__
263
#pragma GCC diagnostic pop
264
#endif
265
free(new_server);
266
return false;
267
}
268
/* Special case of first server */
269
if(*current_server == NULL){
270
new_server->next = new_server;
271
new_server->prev = new_server;
272
*current_server = new_server;
273
} else {
274
/* Place the new server last in the list */
275
new_server->next = *current_server;
276
new_server->prev = (*current_server)->prev;
277
new_server->prev->next = new_server;
278
(*current_server)->prev = new_server;
279
}
280
return true;
281
}
282
283
/* Set effective uid to 0, return errno */
284
__attribute__((warn_unused_result))
285
int raise_privileges(void){
286
int old_errno = errno;
287
int ret = 0;
288
if(seteuid(0) == -1){
289
ret = errno;
290
}
291
errno = old_errno;
292
return ret;
293
}
294
295
/* Set effective and real user ID to 0. Return errno. */
296
__attribute__((warn_unused_result))
297
int raise_privileges_permanently(void){
298
int old_errno = errno;
299
int ret = raise_privileges();
300
if(ret != 0){
301
errno = old_errno;
302
return ret;
303
}
304
if(setuid(0) == -1){
305
ret = errno;
306
}
307
errno = old_errno;
308
return ret;
309
}
310
311
/* Set effective user ID to unprivileged saved user ID */
312
__attribute__((warn_unused_result))
313
int lower_privileges(void){
314
int old_errno = errno;
315
int ret = 0;
316
if(seteuid(uid) == -1){
317
ret = errno;
318
}
319
errno = old_errno;
320
return ret;
321
}
322
323
/* Lower privileges permanently */
324
__attribute__((warn_unused_result))
325
int lower_privileges_permanently(void){
326
int old_errno = errno;
327
int ret = 0;
328
if(setuid(uid) == -1){
329
ret = errno;
330
}
331
errno = old_errno;
332
return ret;
333
}
334
146
335
/*
147
336
* Initialize GPGME.
148
337
*/
149
static bool init_gpgme(mandos_context *mc, const char *seckey,
150
const char *pubkey, const char *tempdir){
151
int ret;
338
__attribute__((nonnull, warn_unused_result))
339
static bool init_gpgme(const char * const seckey,
340
const char * const pubkey,
341
const char * const tempdir,
342
mandos_context *mc){
152
343
gpgme_error_t rc;
153
344
gpgme_engine_info_t engine_info;
154
345
155
156
346
/*
157
347
* Helper function to insert pub and seckey to the engine keyring.
158
348
*/
159
bool import_key(const char *filename){
349
bool import_key(const char * const filename){
350
int ret;
160
351
int fd;
161
352
gpgme_data_t pgp_data;
162
353
163
354
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
164
355
if(fd == -1){
165
perror("open");
356
perror_plus("open");
166
357
return false;
167
358
}
168
359
360
/* Workaround for systems without a real-time clock; see also
361
Debian bug #894495: <https://bugs.debian.org/894495> */
362
do {
363
{
364
time_t currtime = time(NULL);
365
if(currtime != (time_t)-1){
366
struct tm tm;
367
if(gmtime_r(&currtime, &tm) == NULL) {
368
perror_plus("gmtime_r");
369
break;
370
}
371
if(tm.tm_year != 70 or tm.tm_mon != 0){
372
break;
373
}
374
if(debug){
375
fprintf_plus(stderr, "System clock is January 1970");
376
}
377
} else {
378
if(debug){
379
fprintf_plus(stderr, "System clock is invalid");
380
}
381
}
382
}
383
struct stat keystat;
384
ret = fstat(fd, &keystat);
385
if(ret != 0){
386
perror_plus("fstat");
387
break;
388
}
389
ret = raise_privileges();
390
if(ret != 0){
391
errno = ret;
392
perror_plus("Failed to raise privileges");
393
break;
394
}
395
if(debug){
396
fprintf_plus(stderr,
397
"Setting system clock to key file mtime");
398
}
399
time_t keytime = keystat.st_mtim.tv_sec;
400
if(stime(&keytime) != 0){
401
perror_plus("stime");
402
}
403
ret = lower_privileges();
404
if(ret != 0){
405
errno = ret;
406
perror_plus("Failed to lower privileges");
407
}
408
} while(false);
409
169
410
rc = gpgme_data_new_from_fd(&pgp_data, fd);
170
411
if(rc != GPG_ERR_NO_ERROR){
171
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
172
gpgme_strsource(rc), gpgme_strerror(rc));
412
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
173
414
return false;
174
415
}
175
416
176
417
rc = gpgme_op_import(mc->ctx, pgp_data);
177
418
if(rc != GPG_ERR_NO_ERROR){
178
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
179
gpgme_strsource(rc), gpgme_strerror(rc));
419
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
420
gpgme_strsource(rc), gpgme_strerror(rc));
180
421
return false;
181
422
}
423
{
424
gpgme_import_result_t import_result
425
= gpgme_op_import_result(mc->ctx);
426
if((import_result->imported < 1
427
or import_result->not_imported > 0)
428
and import_result->unchanged == 0){
429
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
430
fprintf_plus(stderr,
431
"The total number of considered keys: %d\n",
432
import_result->considered);
433
fprintf_plus(stderr,
434
"The number of keys without user ID: %d\n",
435
import_result->no_user_id);
436
fprintf_plus(stderr,
437
"The total number of imported keys: %d\n",
438
import_result->imported);
439
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
440
import_result->imported_rsa);
441
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
442
import_result->unchanged);
443
fprintf_plus(stderr, "The number of new user IDs: %d\n",
444
import_result->new_user_ids);
445
fprintf_plus(stderr, "The number of new sub keys: %d\n",
446
import_result->new_sub_keys);
447
fprintf_plus(stderr, "The number of new signatures: %d\n",
448
import_result->new_signatures);
449
fprintf_plus(stderr, "The number of new revocations: %d\n",
450
import_result->new_revocations);
451
fprintf_plus(stderr,
452
"The total number of secret keys read: %d\n",
453
import_result->secret_read);
454
fprintf_plus(stderr,
455
"The number of imported secret keys: %d\n",
456
import_result->secret_imported);
457
fprintf_plus(stderr,
458
"The number of unchanged secret keys: %d\n",
459
import_result->secret_unchanged);
460
fprintf_plus(stderr, "The number of keys not imported: %d\n",
461
import_result->not_imported);
462
for(gpgme_import_status_t import_status
463
= import_result->imports;
464
import_status != NULL;
465
import_status = import_status->next){
466
fprintf_plus(stderr, "Import status for key: %s\n",
467
import_status->fpr);
468
if(import_status->result != GPG_ERR_NO_ERROR){
469
fprintf_plus(stderr, "Import result: %s: %s\n",
470
gpgme_strsource(import_status->result),
471
gpgme_strerror(import_status->result));
472
}
473
fprintf_plus(stderr, "Key status:\n");
474
fprintf_plus(stderr,
475
import_status->status & GPGME_IMPORT_NEW
476
? "The key was new.\n"
477
: "The key was not new.\n");
478
fprintf_plus(stderr,
479
import_status->status & GPGME_IMPORT_UID
480
? "The key contained new user IDs.\n"
481
: "The key did not contain new user IDs.\n");
482
fprintf_plus(stderr,
483
import_status->status & GPGME_IMPORT_SIG
484
? "The key contained new signatures.\n"
485
: "The key did not contain new signatures.\n");
486
fprintf_plus(stderr,
487
import_status->status & GPGME_IMPORT_SUBKEY
488
? "The key contained new sub keys.\n"
489
: "The key did not contain new sub keys.\n");
490
fprintf_plus(stderr,
491
import_status->status & GPGME_IMPORT_SECRET
492
? "The key contained a secret key.\n"
493
: "The key did not contain a secret key.\n");
494
}
495
return false;
496
}
497
}
182
498
183
ret = (int)TEMP_FAILURE_RETRY(close(fd));
499
ret = close(fd);
184
500
if(ret == -1){
185
perror("close");
501
perror_plus("close");
186
502
}
187
503
gpgme_data_release(pgp_data);
188
504
return true;
189
505
}
190
506
191
507
if(debug){
192
fprintf(stderr, "Initialize gpgme\n");
508
fprintf_plus(stderr, "Initializing GPGME\n");
193
509
}
194
510
195
511
/* Init GPGME */
196
512
gpgme_check_version(NULL);
197
513
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
198
514
if(rc != GPG_ERR_NO_ERROR){
199
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
200
gpgme_strsource(rc), gpgme_strerror(rc));
515
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
516
gpgme_strsource(rc), gpgme_strerror(rc));
201
517
return false;
202
518
}
203
519
204
/* Set GPGME home directory for the OpenPGP engine only */
520
/* Set GPGME home directory for the OpenPGP engine only */
205
521
rc = gpgme_get_engine_info(&engine_info);
206
522
if(rc != GPG_ERR_NO_ERROR){
207
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
208
gpgme_strsource(rc), gpgme_strerror(rc));
523
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
524
gpgme_strsource(rc), gpgme_strerror(rc));
209
525
return false;
210
526
}
211
527
while(engine_info != NULL){
217
533
engine_info = engine_info->next;
218
534
}
219
535
if(engine_info == NULL){
220
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
536
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
537
tempdir);
221
538
return false;
222
539
}
223
540
224
541
/* Create new GPGME "context" */
225
542
rc = gpgme_new(&(mc->ctx));
226
543
if(rc != GPG_ERR_NO_ERROR){
227
fprintf(stderr, "bad gpgme_new: %s: %s\n",
228
gpgme_strsource(rc), gpgme_strerror(rc));
544
fprintf_plus(stderr, "bad gpgme_new: %s: %s\n",
545
gpgme_strsource(rc), gpgme_strerror(rc));
229
546
return false;
230
547
}
231
548
233
550
return false;
234
551
}
235
552
236
return true;
553
return true;
237
554
}
238
555
239
556
/*
240
557
* Decrypt OpenPGP data.
241
558
* Returns -1 on error
242
559
*/
243
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
244
const char *cryptotext,
560
__attribute__((nonnull, warn_unused_result))
561
static ssize_t pgp_packet_decrypt(const char *cryptotext,
245
562
size_t crypto_size,
246
char **plaintext){
563
char **plaintext,
564
mandos_context *mc){
247
565
gpgme_data_t dh_crypto, dh_plain;
248
566
gpgme_error_t rc;
249
567
ssize_t ret;
251
569
ssize_t plaintext_length = 0;
252
570
253
571
if(debug){
254
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
572
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
255
573
}
256
574
257
575
/* Create new GPGME data buffer from memory cryptotext */
258
576
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
259
577
0);
260
578
if(rc != GPG_ERR_NO_ERROR){
261
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
262
gpgme_strsource(rc), gpgme_strerror(rc));
579
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
580
gpgme_strsource(rc), gpgme_strerror(rc));
263
581
return -1;
264
582
}
265
583
266
584
/* Create new empty GPGME data buffer for the plaintext */
267
585
rc = gpgme_data_new(&dh_plain);
268
586
if(rc != GPG_ERR_NO_ERROR){
269
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
270
gpgme_strsource(rc), gpgme_strerror(rc));
587
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
588
gpgme_strsource(rc), gpgme_strerror(rc));
271
589
gpgme_data_release(dh_crypto);
272
590
return -1;
273
591
}
276
594
data buffer */
277
595
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
278
596
if(rc != GPG_ERR_NO_ERROR){
279
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
280
gpgme_strsource(rc), gpgme_strerror(rc));
597
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
598
gpgme_strsource(rc), gpgme_strerror(rc));
281
599
plaintext_length = -1;
282
600
if(debug){
283
601
gpgme_decrypt_result_t result;
284
602
result = gpgme_op_decrypt_result(mc->ctx);
285
603
if(result == NULL){
286
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
604
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
287
605
} else {
288
fprintf(stderr, "Unsupported algorithm: %s\n",
289
result->unsupported_algorithm);
290
fprintf(stderr, "Wrong key usage: %u\n",
291
result->wrong_key_usage);
606
if(result->unsupported_algorithm != NULL) {
607
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
608
result->unsupported_algorithm);
609
}
610
fprintf_plus(stderr, "Wrong key usage: %s\n",
611
result->wrong_key_usage ? "Yes" : "No");
292
612
if(result->file_name != NULL){
293
fprintf(stderr, "File name: %s\n", result->file_name);
613
fprintf_plus(stderr, "File name: %s\n", result->file_name);
294
614
}
295
gpgme_recipient_t recipient;
296
recipient = result->recipients;
297
if(recipient){
298
while(recipient != NULL){
299
fprintf(stderr, "Public key algorithm: %s\n",
300
gpgme_pubkey_algo_name(recipient->pubkey_algo));
301
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
302
fprintf(stderr, "Secret key available: %s\n",
303
recipient->status == GPG_ERR_NO_SECKEY
304
? "No" : "Yes");
305
recipient = recipient->next;
306
}
615
616
for(gpgme_recipient_t r = result->recipients; r != NULL;
617
r = r->next){
618
fprintf_plus(stderr, "Public key algorithm: %s\n",
619
gpgme_pubkey_algo_name(r->pubkey_algo));
620
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
621
fprintf_plus(stderr, "Secret key available: %s\n",
622
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
307
623
}
308
624
}
309
625
}
311
627
}
312
628
313
629
if(debug){
314
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
630
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
315
631
}
316
632
317
633
/* Seek back to the beginning of the GPGME plaintext data buffer */
318
634
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
319
perror("gpgme_data_seek");
635
perror_plus("gpgme_data_seek");
320
636
plaintext_length = -1;
321
637
goto decrypt_end;
322
638
}
323
639
324
640
*plaintext = NULL;
325
641
while(true){
326
plaintext_capacity = adjustbuffer(plaintext,
327
(size_t)plaintext_length,
328
plaintext_capacity);
642
plaintext_capacity = incbuffer(plaintext,
643
(size_t)plaintext_length,
644
plaintext_capacity);
329
645
if(plaintext_capacity == 0){
330
perror("adjustbuffer");
331
plaintext_length = -1;
332
goto decrypt_end;
646
perror_plus("incbuffer");
647
plaintext_length = -1;
648
goto decrypt_end;
333
649
}
334
650
335
651
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
340
656
break;
341
657
}
342
658
if(ret < 0){
343
perror("gpgme_data_read");
659
perror_plus("gpgme_data_read");
344
660
plaintext_length = -1;
345
661
goto decrypt_end;
346
662
}
348
664
}
349
665
350
666
if(debug){
351
fprintf(stderr, "Decrypted password is: ");
667
fprintf_plus(stderr, "Decrypted password is: ");
352
668
for(ssize_t i = 0; i < plaintext_length; i++){
353
669
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
354
670
}
365
681
return plaintext_length;
366
682
}
367
683
368
static const char * safer_gnutls_strerror(int value) {
369
const char *ret = gnutls_strerror(value); /* Spurious warning from
370
-Wunreachable-code */
371
if(ret == NULL)
372
ret = "(unknown)";
373
return ret;
684
__attribute__((warn_unused_result, const))
685
static const char *safe_string(const char *str){
686
if(str == NULL)
687
return "(unknown)";
688
return str;
689
}
690
691
__attribute__((warn_unused_result))
692
static const char *safer_gnutls_strerror(int value){
693
const char *ret = gnutls_strerror(value);
694
return safe_string(ret);
374
695
}
375
696
376
697
/* GnuTLS log function callback */
698
__attribute__((nonnull))
377
699
static void debuggnutls(__attribute__((unused)) int level,
378
700
const char* string){
379
fprintf(stderr, "GnuTLS: %s", string);
701
fprintf_plus(stderr, "GnuTLS: %s", string);
380
702
}
381
703
382
static int init_gnutls_global(mandos_context *mc,
383
const char *pubkeyfilename,
384
const char *seckeyfilename){
704
__attribute__((nonnull(1, 2, 4), warn_unused_result))
705
static int init_gnutls_global(const char *pubkeyfilename,
706
const char *seckeyfilename,
707
const char *dhparamsfilename,
708
mandos_context *mc){
385
709
int ret;
386
710
387
711
if(debug){
388
fprintf(stderr, "Initializing GnuTLS\n");
389
}
390
391
ret = gnutls_global_init();
392
if(ret != GNUTLS_E_SUCCESS) {
393
fprintf(stderr, "GnuTLS global_init: %s\n",
394
safer_gnutls_strerror(ret));
395
return -1;
712
fprintf_plus(stderr, "Initializing GnuTLS\n");
396
713
}
397
714
398
715
if(debug){
404
721
}
405
722
406
723
/* OpenPGP credentials */
407
gnutls_certificate_allocate_credentials(&mc->cred);
724
ret = gnutls_certificate_allocate_credentials(&mc->cred);
408
725
if(ret != GNUTLS_E_SUCCESS){
409
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
410
* from
411
* -Wunreachable-code
412
*/
413
safer_gnutls_strerror(ret));
414
gnutls_global_deinit();
726
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
727
safer_gnutls_strerror(ret));
415
728
return -1;
416
729
}
417
730
418
731
if(debug){
419
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
420
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
421
seckeyfilename);
732
fprintf_plus(stderr, "Attempting to use public key %s and"
733
" private key %s as GnuTLS credentials\n",
734
pubkeyfilename,
735
seckeyfilename);
422
736
}
423
737
738
#if GNUTLS_VERSION_NUMBER >= 0x030606
739
ret = gnutls_certificate_set_rawpk_key_file
740
(mc->cred, pubkeyfilename, seckeyfilename,
741
GNUTLS_X509_FMT_PEM, /* format */
742
NULL, /* pass */
743
/* key_usage */
744
GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,
745
NULL, /* names */
746
0, /* names_length */
747
/* privkey_flags */
748
GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,
749
0); /* pkcs11_flags */
750
#elif GNUTLS_VERSION_NUMBER < 0x030600
424
751
ret = gnutls_certificate_set_openpgp_key_file
425
752
(mc->cred, pubkeyfilename, seckeyfilename,
426
753
GNUTLS_OPENPGP_FMT_BASE64);
427
if(ret != GNUTLS_E_SUCCESS) {
428
fprintf(stderr,
429
"Error[%d] while reading the OpenPGP key pair ('%s',"
430
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
431
fprintf(stderr, "The GnuTLS error is: %s\n",
432
safer_gnutls_strerror(ret));
754
#else
755
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
756
#endif
757
if(ret != GNUTLS_E_SUCCESS){
758
fprintf_plus(stderr,
759
"Error[%d] while reading the key pair ('%s',"
760
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
761
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
762
safer_gnutls_strerror(ret));
433
763
goto globalfail;
434
764
}
435
765
436
766
/* GnuTLS server initialization */
437
767
ret = gnutls_dh_params_init(&mc->dh_params);
438
if(ret != GNUTLS_E_SUCCESS) {
439
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
440
" %s\n", safer_gnutls_strerror(ret));
441
goto globalfail;
442
}
443
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
444
if(ret != GNUTLS_E_SUCCESS) {
445
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
446
safer_gnutls_strerror(ret));
447
goto globalfail;
448
}
449
450
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
768
if(ret != GNUTLS_E_SUCCESS){
769
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
770
" initialization: %s\n",
771
safer_gnutls_strerror(ret));
772
goto globalfail;
773
}
774
/* If a Diffie-Hellman parameters file was given, try to use it */
775
if(dhparamsfilename != NULL){
776
gnutls_datum_t params = { .data = NULL, .size = 0 };
777
do {
778
int dhpfile = open(dhparamsfilename, O_RDONLY);
779
if(dhpfile == -1){
780
perror_plus("open");
781
dhparamsfilename = NULL;
782
break;
783
}
784
size_t params_capacity = 0;
785
while(true){
786
params_capacity = incbuffer((char **)¶ms.data,
787
(size_t)params.size,
788
(size_t)params_capacity);
789
if(params_capacity == 0){
790
perror_plus("incbuffer");
791
free(params.data);
792
params.data = NULL;
793
dhparamsfilename = NULL;
794
break;
795
}
796
ssize_t bytes_read = read(dhpfile,
797
params.data + params.size,
798
BUFFER_SIZE);
799
/* EOF */
800
if(bytes_read == 0){
801
break;
802
}
803
/* check bytes_read for failure */
804
if(bytes_read < 0){
805
perror_plus("read");
806
free(params.data);
807
params.data = NULL;
808
dhparamsfilename = NULL;
809
break;
810
}
811
params.size += (unsigned int)bytes_read;
812
}
813
ret = close(dhpfile);
814
if(ret == -1){
815
perror_plus("close");
816
}
817
if(params.data == NULL){
818
dhparamsfilename = NULL;
819
}
820
if(dhparamsfilename == NULL){
821
break;
822
}
823
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
824
GNUTLS_X509_FMT_PEM);
825
if(ret != GNUTLS_E_SUCCESS){
826
fprintf_plus(stderr, "Failed to parse DH parameters in file"
827
" \"%s\": %s\n", dhparamsfilename,
828
safer_gnutls_strerror(ret));
829
dhparamsfilename = NULL;
830
}
831
free(params.data);
832
} while(false);
833
}
834
if(dhparamsfilename == NULL){
835
if(mc->dh_bits == 0){
836
#if GNUTLS_VERSION_NUMBER < 0x030600
837
/* Find out the optimal number of DH bits */
838
/* Try to read the private key file */
839
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
840
do {
841
int secfile = open(seckeyfilename, O_RDONLY);
842
if(secfile == -1){
843
perror_plus("open");
844
break;
845
}
846
size_t buffer_capacity = 0;
847
while(true){
848
buffer_capacity = incbuffer((char **)&buffer.data,
849
(size_t)buffer.size,
850
(size_t)buffer_capacity);
851
if(buffer_capacity == 0){
852
perror_plus("incbuffer");
853
free(buffer.data);
854
buffer.data = NULL;
855
break;
856
}
857
ssize_t bytes_read = read(secfile,
858
buffer.data + buffer.size,
859
BUFFER_SIZE);
860
/* EOF */
861
if(bytes_read == 0){
862
break;
863
}
864
/* check bytes_read for failure */
865
if(bytes_read < 0){
866
perror_plus("read");
867
free(buffer.data);
868
buffer.data = NULL;
869
break;
870
}
871
buffer.size += (unsigned int)bytes_read;
872
}
873
close(secfile);
874
} while(false);
875
/* If successful, use buffer to parse private key */
876
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
877
if(buffer.data != NULL){
878
{
879
gnutls_openpgp_privkey_t privkey = NULL;
880
ret = gnutls_openpgp_privkey_init(&privkey);
881
if(ret != GNUTLS_E_SUCCESS){
882
fprintf_plus(stderr, "Error initializing OpenPGP key"
883
" structure: %s",
884
safer_gnutls_strerror(ret));
885
free(buffer.data);
886
buffer.data = NULL;
887
} else {
888
ret = gnutls_openpgp_privkey_import
889
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
890
if(ret != GNUTLS_E_SUCCESS){
891
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
892
safer_gnutls_strerror(ret));
893
privkey = NULL;
894
}
895
free(buffer.data);
896
buffer.data = NULL;
897
if(privkey != NULL){
898
/* Use private key to suggest an appropriate
899
sec_param */
900
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
901
gnutls_openpgp_privkey_deinit(privkey);
902
if(debug){
903
fprintf_plus(stderr, "This OpenPGP key implies using"
904
" a GnuTLS security parameter \"%s\".\n",
905
safe_string(gnutls_sec_param_get_name
906
(sec_param)));
907
}
908
}
909
}
910
}
911
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
912
/* Err on the side of caution */
913
sec_param = GNUTLS_SEC_PARAM_ULTRA;
914
if(debug){
915
fprintf_plus(stderr, "Falling back to security parameter"
916
" \"%s\"\n",
917
safe_string(gnutls_sec_param_get_name
918
(sec_param)));
919
}
920
}
921
}
922
unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
923
if(uret != 0){
924
mc->dh_bits = uret;
925
if(debug){
926
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
927
" implies %u DH bits; using that.\n",
928
safe_string(gnutls_sec_param_get_name
929
(sec_param)),
930
mc->dh_bits);
931
}
932
} else {
933
fprintf_plus(stderr, "Failed to get implied number of DH"
934
" bits for security parameter \"%s\"): %s\n",
935
safe_string(gnutls_sec_param_get_name
936
(sec_param)),
937
safer_gnutls_strerror(ret));
938
goto globalfail;
939
}
940
#endif
941
} else { /* dh_bits != 0 */
942
if(debug){
943
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
944
mc->dh_bits);
945
}
946
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
947
if(ret != GNUTLS_E_SUCCESS){
948
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
949
" bits): %s\n", mc->dh_bits,
950
safer_gnutls_strerror(ret));
951
goto globalfail;
952
}
953
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
954
}
955
}
451
956
452
957
return 0;
453
958
454
959
globalfail:
455
960
456
961
gnutls_certificate_free_credentials(mc->cred);
457
gnutls_global_deinit();
458
962
gnutls_dh_params_deinit(mc->dh_params);
459
963
return -1;
460
964
}
461
965
462
static int init_gnutls_session(mandos_context *mc,
463
gnutls_session_t *session){
966
__attribute__((nonnull, warn_unused_result))
967
static int init_gnutls_session(gnutls_session_t *session,
968
mandos_context *mc){
464
969
int ret;
465
970
/* GnuTLS session creation */
466
ret = gnutls_init(session, GNUTLS_SERVER);
971
do {
972
ret = gnutls_init(session, (GNUTLS_SERVER
973
#if GNUTLS_VERSION_NUMBER >= 0x030506
974
| GNUTLS_NO_TICKETS
975
#endif
976
#if GNUTLS_VERSION_NUMBER >= 0x030606
977
| GNUTLS_ENABLE_RAWPK
978
#endif
979
));
980
if(quit_now){
981
return -1;
982
}
983
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
467
984
if(ret != GNUTLS_E_SUCCESS){
468
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
469
safer_gnutls_strerror(ret));
985
fprintf_plus(stderr,
986
"Error in GnuTLS session initialization: %s\n",
987
safer_gnutls_strerror(ret));
470
988
}
471
989
472
990
{
473
991
const char *err;
474
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
475
if(ret != GNUTLS_E_SUCCESS) {
476
fprintf(stderr, "Syntax error at: %s\n", err);
477
fprintf(stderr, "GnuTLS error: %s\n",
478
safer_gnutls_strerror(ret));
992
do {
993
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
994
if(quit_now){
995
gnutls_deinit(*session);
996
return -1;
997
}
998
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
999
if(ret != GNUTLS_E_SUCCESS){
1000
fprintf_plus(stderr, "Syntax error at: %s\n", err);
1001
fprintf_plus(stderr, "GnuTLS error: %s\n",
1002
safer_gnutls_strerror(ret));
479
1003
gnutls_deinit(*session);
480
1004
return -1;
481
1005
}
482
1006
}
483
1007
484
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
485
mc->cred);
486
if(ret != GNUTLS_E_SUCCESS) {
487
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
488
safer_gnutls_strerror(ret));
1008
do {
1009
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
1010
mc->cred);
1011
if(quit_now){
1012
gnutls_deinit(*session);
1013
return -1;
1014
}
1015
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
1016
if(ret != GNUTLS_E_SUCCESS){
1017
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
1018
safer_gnutls_strerror(ret));
489
1019
gnutls_deinit(*session);
490
1020
return -1;
491
1021
}
492
1022
493
1023
/* ignore client certificate if any. */
494
gnutls_certificate_server_set_request(*session,
495
GNUTLS_CERT_IGNORE);
496
497
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
1024
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
498
1025
499
1026
return 0;
500
1027
}
503
1030
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
504
1031
__attribute__((unused)) const char *txt){}
505
1032
1033
/* Helper function to add_local_route() and delete_local_route() */
1034
__attribute__((nonnull, warn_unused_result))
1035
static bool add_delete_local_route(const bool add,
1036
const char *address,
1037
AvahiIfIndex if_index){
1038
int ret;
1039
char helper[] = "mandos-client-iprouteadddel";
1040
char add_arg[] = "add";
1041
char delete_arg[] = "delete";
1042
char debug_flag[] = "--debug";
1043
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1044
if(pluginhelperdir == NULL){
1045
if(debug){
1046
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
1047
" variable not set; cannot run helper\n");
1048
}
1049
return false;
1050
}
1051
1052
char interface[IF_NAMESIZE];
1053
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1054
perror_plus("if_indextoname");
1055
return false;
1056
}
1057
1058
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1059
if(devnull == -1){
1060
perror_plus("open(\"/dev/null\", O_RDONLY)");
1061
return false;
1062
}
1063
pid_t pid = fork();
1064
if(pid == 0){
1065
/* Child */
1066
/* Raise privileges */
1067
errno = raise_privileges_permanently();
1068
if(errno != 0){
1069
perror_plus("Failed to raise privileges");
1070
/* _exit(EX_NOPERM); */
1071
} else {
1072
/* Set group */
1073
errno = 0;
1074
ret = setgid(0);
1075
if(ret == -1){
1076
perror_plus("setgid");
1077
_exit(EX_NOPERM);
1078
}
1079
/* Reset supplementary groups */
1080
errno = 0;
1081
ret = setgroups(0, NULL);
1082
if(ret == -1){
1083
perror_plus("setgroups");
1084
_exit(EX_NOPERM);
1085
}
1086
}
1087
ret = dup2(devnull, STDIN_FILENO);
1088
if(ret == -1){
1089
perror_plus("dup2(devnull, STDIN_FILENO)");
1090
_exit(EX_OSERR);
1091
}
1092
ret = close(devnull);
1093
if(ret == -1){
1094
perror_plus("close");
1095
_exit(EX_OSERR);
1096
}
1097
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1098
if(ret == -1){
1099
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1100
_exit(EX_OSERR);
1101
}
1102
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1103
O_RDONLY
1104
| O_DIRECTORY
1105
| O_PATH
1106
| O_CLOEXEC));
1107
if(helperdir_fd == -1){
1108
perror_plus("open");
1109
_exit(EX_UNAVAILABLE);
1110
}
1111
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1112
helper, O_RDONLY));
1113
if(helper_fd == -1){
1114
perror_plus("openat");
1115
close(helperdir_fd);
1116
_exit(EX_UNAVAILABLE);
1117
}
1118
close(helperdir_fd);
1119
#ifdef __GNUC__
1120
#pragma GCC diagnostic push
1121
#pragma GCC diagnostic ignored "-Wcast-qual"
1122
#endif
1123
if(fexecve(helper_fd, (char *const [])
1124
{ helper, add ? add_arg : delete_arg, (char *)address,
1125
interface, debug ? debug_flag : NULL, NULL },
1126
environ) == -1){
1127
#ifdef __GNUC__
1128
#pragma GCC diagnostic pop
1129
#endif
1130
perror_plus("fexecve");
1131
_exit(EXIT_FAILURE);
1132
}
1133
}
1134
if(pid == -1){
1135
perror_plus("fork");
1136
return false;
1137
}
1138
int status;
1139
pid_t pret = -1;
1140
errno = 0;
1141
do {
1142
pret = waitpid(pid, &status, 0);
1143
if(pret == -1 and errno == EINTR and quit_now){
1144
int errno_raising = 0;
1145
if((errno = raise_privileges()) != 0){
1146
errno_raising = errno;
1147
perror_plus("Failed to raise privileges in order to"
1148
" kill helper program");
1149
}
1150
if(kill(pid, SIGTERM) == -1){
1151
perror_plus("kill");
1152
}
1153
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1154
perror_plus("Failed to lower privileges after killing"
1155
" helper program");
1156
}
1157
return false;
1158
}
1159
} while(pret == -1 and errno == EINTR);
1160
if(pret == -1){
1161
perror_plus("waitpid");
1162
return false;
1163
}
1164
if(WIFEXITED(status)){
1165
if(WEXITSTATUS(status) != 0){
1166
fprintf_plus(stderr, "Error: iprouteadddel exited"
1167
" with status %d\n", WEXITSTATUS(status));
1168
return false;
1169
}
1170
return true;
1171
}
1172
if(WIFSIGNALED(status)){
1173
fprintf_plus(stderr, "Error: iprouteadddel died by"
1174
" signal %d\n", WTERMSIG(status));
1175
return false;
1176
}
1177
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1178
return false;
1179
}
1180
1181
__attribute__((nonnull, warn_unused_result))
1182
static bool add_local_route(const char *address,
1183
AvahiIfIndex if_index){
1184
if(debug){
1185
fprintf_plus(stderr, "Adding route to %s\n", address);
1186
}
1187
return add_delete_local_route(true, address, if_index);
1188
}
1189
1190
__attribute__((nonnull, warn_unused_result))
1191
static bool delete_local_route(const char *address,
1192
AvahiIfIndex if_index){
1193
if(debug){
1194
fprintf_plus(stderr, "Removing route to %s\n", address);
1195
}
1196
return add_delete_local_route(false, address, if_index);
1197
}
1198
506
1199
/* Called when a Mandos server is found */
507
static int start_mandos_communication(const char *ip, uint16_t port,
1200
__attribute__((nonnull, warn_unused_result))
1201
static int start_mandos_communication(const char *ip, in_port_t port,
508
1202
AvahiIfIndex if_index,
509
mandos_context *mc){
510
int ret, tcp_sd;
1203
int af, mandos_context *mc){
1204
int ret, tcp_sd = -1;
511
1205
ssize_t sret;
512
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1206
struct sockaddr_storage to;
513
1207
char *buffer = NULL;
514
char *decrypted_buffer;
1208
char *decrypted_buffer = NULL;
515
1209
size_t buffer_length = 0;
516
1210
size_t buffer_capacity = 0;
517
ssize_t decrypted_buffer_size;
518
1211
size_t written;
519
int retval = 0;
520
char interface[IF_NAMESIZE];
1212
int retval = -1;
521
1213
gnutls_session_t session;
522
523
ret = init_gnutls_session(mc, &session);
1214
int pf; /* Protocol family */
1215
bool route_added = false;
1216
1217
errno = 0;
1218
1219
if(quit_now){
1220
errno = EINTR;
1221
return -1;
1222
}
1223
1224
switch(af){
1225
case AF_INET6:
1226
pf = PF_INET6;
1227
break;
1228
case AF_INET:
1229
pf = PF_INET;
1230
break;
1231
default:
1232
fprintf_plus(stderr, "Bad address family: %d\n", af);
1233
errno = EINVAL;
1234
return -1;
1235
}
1236
1237
/* If the interface is specified and we have a list of interfaces */
1238
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1239
/* Check if the interface is one of the interfaces we are using */
1240
bool match = false;
1241
{
1242
char *interface = NULL;
1243
while((interface = argz_next(mc->interfaces,
1244
mc->interfaces_size,
1245
interface))){
1246
if(if_nametoindex(interface) == (unsigned int)if_index){
1247
match = true;
1248
break;
1249
}
1250
}
1251
}
1252
if(not match){
1253
/* This interface does not match any in the list, so we don't
1254
connect to the server */
1255
if(debug){
1256
char interface[IF_NAMESIZE];
1257
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1258
perror_plus("if_indextoname");
1259
} else {
1260
fprintf_plus(stderr, "Skipping server on non-used interface"
1261
" \"%s\"\n",
1262
if_indextoname((unsigned int)if_index,
1263
interface));
1264
}
1265
}
1266
return -1;
1267
}
1268
}
1269
1270
ret = init_gnutls_session(&session, mc);
524
1271
if(ret != 0){
525
1272
return -1;
526
1273
}
527
1274
528
1275
if(debug){
529
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
530
"\n", ip, port);
531
}
532
533
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
534
if(tcp_sd < 0) {
535
perror("socket");
536
return -1;
537
}
538
539
if(debug){
540
if(if_indextoname((unsigned int)if_index, interface) == NULL){
541
perror("if_indextoname");
542
return -1;
543
}
544
fprintf(stderr, "Binding to interface %s\n", interface);
545
}
546
547
memset(&to, 0, sizeof(to));
548
to.in6.sin6_family = AF_INET6;
549
/* It would be nice to have a way to detect if we were passed an
550
IPv4 address here. Now we assume an IPv6 address. */
551
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
1276
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1277
PRIuMAX "\n", ip, (uintmax_t)port);
1278
}
1279
1280
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1281
if(tcp_sd < 0){
1282
int e = errno;
1283
perror_plus("socket");
1284
errno = e;
1285
goto mandos_end;
1286
}
1287
1288
if(quit_now){
1289
errno = EINTR;
1290
goto mandos_end;
1291
}
1292
1293
if(af == AF_INET6){
1294
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1295
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1296
ret = inet_pton(af, ip, &to6->sin6_addr);
1297
} else { /* IPv4 */
1298
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1299
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1300
ret = inet_pton(af, ip, &to4->sin_addr);
1301
}
552
1302
if(ret < 0 ){
553
perror("inet_pton");
554
return -1;
1303
int e = errno;
1304
perror_plus("inet_pton");
1305
errno = e;
1306
goto mandos_end;
555
1307
}
556
1308
if(ret == 0){
557
fprintf(stderr, "Bad address: %s\n", ip);
558
return -1;
559
}
560
to.in6.sin6_port = htons(port); /* Spurious warnings from
561
-Wconversion and
562
-Wunreachable-code */
1309
int e = errno;
1310
fprintf_plus(stderr, "Bad address: %s\n", ip);
1311
errno = e;
1312
goto mandos_end;
1313
}
1314
if(af == AF_INET6){
1315
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1316
if(IN6_IS_ADDR_LINKLOCAL
1317
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1318
if(if_index == AVAHI_IF_UNSPEC){
1319
fprintf_plus(stderr, "An IPv6 link-local address is"
1320
" incomplete without a network interface\n");
1321
errno = EINVAL;
1322
goto mandos_end;
1323
}
1324
/* Set the network interface number as scope */
1325
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1326
}
1327
} else {
1328
((struct sockaddr_in *)&to)->sin_port = htons(port);
1329
}
563
1330
564
to.in6.sin6_scope_id = (uint32_t)if_index;
1331
if(quit_now){
1332
errno = EINTR;
1333
goto mandos_end;
1334
}
565
1335
566
1336
if(debug){
567
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
568
port);
569
char addrstr[INET6_ADDRSTRLEN] = "";
570
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
571
sizeof(addrstr)) == NULL){
572
perror("inet_ntop");
573
} else {
574
if(strcmp(addrstr, ip) != 0){
575
fprintf(stderr, "Canonical address form: %s\n", addrstr);
576
}
577
}
578
}
579
580
ret = connect(tcp_sd, &to.in, sizeof(to));
581
if(ret < 0){
582
perror("connect");
583
return -1;
1337
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1338
char interface[IF_NAMESIZE];
1339
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1340
perror_plus("if_indextoname");
1341
} else {
1342
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1343
"\n", ip, interface, (uintmax_t)port);
1344
}
1345
} else {
1346
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1347
ip, (uintmax_t)port);
1348
}
1349
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1350
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1351
if(af == AF_INET6){
1352
ret = getnameinfo((struct sockaddr *)&to,
1353
sizeof(struct sockaddr_in6),
1354
addrstr, sizeof(addrstr), NULL, 0,
1355
NI_NUMERICHOST);
1356
} else {
1357
ret = getnameinfo((struct sockaddr *)&to,
1358
sizeof(struct sockaddr_in),
1359
addrstr, sizeof(addrstr), NULL, 0,
1360
NI_NUMERICHOST);
1361
}
1362
if(ret == EAI_SYSTEM){
1363
perror_plus("getnameinfo");
1364
} else if(ret != 0) {
1365
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1366
} else if(strcmp(addrstr, ip) != 0){
1367
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1368
}
1369
}
1370
1371
if(quit_now){
1372
errno = EINTR;
1373
goto mandos_end;
1374
}
1375
1376
while(true){
1377
if(af == AF_INET6){
1378
ret = connect(tcp_sd, (struct sockaddr *)&to,
1379
sizeof(struct sockaddr_in6));
1380
} else {
1381
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1382
sizeof(struct sockaddr_in));
1383
}
1384
if(ret < 0){
1385
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1386
and if_index != AVAHI_IF_UNSPEC
1387
and connect_to == NULL
1388
and not route_added and
1389
((af == AF_INET6 and not
1390
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1391
&to)->sin6_addr)))
1392
or (af == AF_INET and
1393
/* Not a a IPv4LL address */
1394
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1395
& 0xFFFF0000L) != 0xA9FE0000L))){
1396
/* Work around Avahi bug - Avahi does not announce link-local
1397
addresses if it has a global address, so local hosts with
1398
*only* a link-local address (e.g. Mandos clients) cannot
1399
connect to a Mandos server announced by Avahi on a server
1400
host with a global address. Work around this by retrying
1401
with an explicit route added with the server's address.
1402
1403
Avahi bug reference:
1404
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1405
https://bugs.debian.org/587961
1406
*/
1407
if(debug){
1408
fprintf_plus(stderr, "Mandos server unreachable, trying"
1409
" direct route\n");
1410
}
1411
int e = errno;
1412
route_added = add_local_route(ip, if_index);
1413
if(route_added){
1414
continue;
1415
}
1416
errno = e;
1417
}
1418
if(errno != ECONNREFUSED or debug){
1419
int e = errno;
1420
perror_plus("connect");
1421
errno = e;
1422
}
1423
goto mandos_end;
1424
}
1425
1426
if(quit_now){
1427
errno = EINTR;
1428
goto mandos_end;
1429
}
1430
break;
584
1431
}
585
1432
586
1433
const char *out = mandos_protocol_version;
588
1435
while(true){
589
1436
size_t out_size = strlen(out);
590
1437
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
591
out_size - written));
1438
out_size - written));
592
1439
if(ret == -1){
593
perror("write");
594
retval = -1;
1440
int e = errno;
1441
perror_plus("write");
1442
errno = e;
595
1443
goto mandos_end;
596
1444
}
597
1445
written += (size_t)ret;
605
1453
break;
606
1454
}
607
1455
}
1456
1457
if(quit_now){
1458
errno = EINTR;
1459
goto mandos_end;
1460
}
608
1461
}
609
1462
610
1463
if(debug){
611
fprintf(stderr, "Establishing TLS session with %s\n", ip);
612
}
613
614
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
615
616
do{
1464
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1465
}
1466
1467
if(quit_now){
1468
errno = EINTR;
1469
goto mandos_end;
1470
}
1471
1472
/* This casting via intptr_t is to eliminate warning about casting
1473
an int to a pointer type. This is exactly how the GnuTLS Guile
1474
function "set-session-transport-fd!" does it. */
1475
gnutls_transport_set_ptr(session,
1476
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1477
1478
if(quit_now){
1479
errno = EINTR;
1480
goto mandos_end;
1481
}
1482
1483
do {
617
1484
ret = gnutls_handshake(session);
1485
if(quit_now){
1486
errno = EINTR;
1487
goto mandos_end;
1488
}
618
1489
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
619
1490
620
1491
if(ret != GNUTLS_E_SUCCESS){
621
1492
if(debug){
622
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1493
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
623
1494
gnutls_perror(ret);
624
1495
}
625
retval = -1;
1496
errno = EPROTO;
626
1497
goto mandos_end;
627
1498
}
628
1499
629
1500
/* Read OpenPGP packet that contains the wanted password */
630
1501
631
1502
if(debug){
632
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
633
ip);
1503
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1504
" %s\n", ip);
634
1505
}
635
1506
636
1507
while(true){
637
buffer_capacity = adjustbuffer(&buffer, buffer_length,
638
buffer_capacity);
1508
1509
if(quit_now){
1510
errno = EINTR;
1511
goto mandos_end;
1512
}
1513
1514
buffer_capacity = incbuffer(&buffer, buffer_length,
1515
buffer_capacity);
639
1516
if(buffer_capacity == 0){
640
perror("adjustbuffer");
641
retval = -1;
1517
int e = errno;
1518
perror_plus("incbuffer");
1519
errno = e;
1520
goto mandos_end;
1521
}
1522
1523
if(quit_now){
1524
errno = EINTR;
642
1525
goto mandos_end;
643
1526
}
644
1527
653
1536
case GNUTLS_E_AGAIN:
654
1537
break;
655
1538
case GNUTLS_E_REHANDSHAKE:
656
do{
1539
do {
657
1540
ret = gnutls_handshake(session);
1541
1542
if(quit_now){
1543
errno = EINTR;
1544
goto mandos_end;
1545
}
658
1546
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
659
1547
if(ret < 0){
660
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1548
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1549
"***\n");
661
1550
gnutls_perror(ret);
662
retval = -1;
1551
errno = EPROTO;
663
1552
goto mandos_end;
664
1553
}
665
1554
break;
666
1555
default:
667
fprintf(stderr, "Unknown error while reading data from"
668
" encrypted session with Mandos server\n");
669
retval = -1;
1556
fprintf_plus(stderr, "Unknown error while reading data from"
1557
" encrypted session with Mandos server\n");
670
1558
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1559
errno = EIO;
671
1560
goto mandos_end;
672
1561
}
673
1562
} else {
676
1565
}
677
1566
678
1567
if(debug){
679
fprintf(stderr, "Closing TLS session\n");
680
}
681
682
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1568
fprintf_plus(stderr, "Closing TLS session\n");
1569
}
1570
1571
if(quit_now){
1572
errno = EINTR;
1573
goto mandos_end;
1574
}
1575
1576
do {
1577
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1578
if(quit_now){
1579
errno = EINTR;
1580
goto mandos_end;
1581
}
1582
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
683
1583
684
1584
if(buffer_length > 0){
685
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
686
buffer_length,
687
&decrypted_buffer);
1585
ssize_t decrypted_buffer_size;
1586
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1587
&decrypted_buffer, mc);
688
1588
if(decrypted_buffer_size >= 0){
1589
1590
clearerr(stdout);
689
1591
written = 0;
690
1592
while(written < (size_t) decrypted_buffer_size){
1593
if(quit_now){
1594
errno = EINTR;
1595
goto mandos_end;
1596
}
1597
691
1598
ret = (int)fwrite(decrypted_buffer + written, 1,
692
1599
(size_t)decrypted_buffer_size - written,
693
1600
stdout);
694
1601
if(ret == 0 and ferror(stdout)){
1602
int e = errno;
695
1603
if(debug){
696
fprintf(stderr, "Error writing encrypted data: %s\n",
697
strerror(errno));
1604
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1605
strerror(errno));
698
1606
}
699
retval = -1;
700
break;
1607
errno = e;
1608
goto mandos_end;
701
1609
}
702
1610
written += (size_t)ret;
703
1611
}
704
free(decrypted_buffer);
705
} else {
706
retval = -1;
1612
ret = fflush(stdout);
1613
if(ret != 0){
1614
int e = errno;
1615
if(debug){
1616
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1617
strerror(errno));
1618
}
1619
errno = e;
1620
goto mandos_end;
1621
}
1622
retval = 0;
707
1623
}
708
} else {
709
retval = -1;
710
1624
}
711
1625
712
1626
/* Shutdown procedure */
713
1627
714
1628
mandos_end:
715
free(buffer);
716
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
717
if(ret == -1){
718
perror("close");
1629
{
1630
if(route_added){
1631
if(not delete_local_route(ip, if_index)){
1632
fprintf_plus(stderr, "Failed to delete local route to %s on"
1633
" interface %d", ip, if_index);
1634
}
1635
}
1636
int e = errno;
1637
free(decrypted_buffer);
1638
free(buffer);
1639
if(tcp_sd >= 0){
1640
ret = close(tcp_sd);
1641
}
1642
if(ret == -1){
1643
if(e == 0){
1644
e = errno;
1645
}
1646
perror_plus("close");
1647
}
1648
gnutls_deinit(session);
1649
errno = e;
1650
if(quit_now){
1651
errno = EINTR;
1652
retval = -1;
1653
}
719
1654
}
720
gnutls_deinit(session);
721
1655
return retval;
722
1656
}
723
1657
724
1658
static void resolve_callback(AvahiSServiceResolver *r,
725
1659
AvahiIfIndex interface,
726
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1660
AvahiProtocol proto,
727
1661
AvahiResolverEvent event,
728
1662
const char *name,
729
1663
const char *type,
734
1668
AVAHI_GCC_UNUSED AvahiStringList *txt,
735
1669
AVAHI_GCC_UNUSED AvahiLookupResultFlags
736
1670
flags,
737
void* userdata) {
738
mandos_context *mc = userdata;
739
assert(r);
1671
void *mc){
1672
if(r == NULL){
1673
return;
1674
}
740
1675
741
1676
/* Called whenever a service has been resolved successfully or
742
1677
timed out */
743
1678
744
switch(event) {
1679
if(quit_now){
1680
avahi_s_service_resolver_free(r);
1681
return;
1682
}
1683
1684
switch(event){
745
1685
default:
746
1686
case AVAHI_RESOLVER_FAILURE:
747
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
748
" of type '%s' in domain '%s': %s\n", name, type, domain,
749
avahi_strerror(avahi_server_errno(mc->server)));
1687
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1688
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1689
domain,
1690
avahi_strerror(avahi_server_errno
1691
(((mandos_context*)mc)->server)));
750
1692
break;
751
1693
752
1694
case AVAHI_RESOLVER_FOUND:
754
1696
char ip[AVAHI_ADDRESS_STR_MAX];
755
1697
avahi_address_snprint(ip, sizeof(ip), address);
756
1698
if(debug){
757
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
758
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
759
ip, (intmax_t)interface, port);
1699
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1700
PRIdMAX ") on port %" PRIu16 "\n", name,
1701
host_name, ip, (intmax_t)interface, port);
760
1702
}
761
int ret = start_mandos_communication(ip, port, interface, mc);
1703
int ret = start_mandos_communication(ip, (in_port_t)port,
1704
interface,
1705
avahi_proto_to_af(proto),
1706
mc);
762
1707
if(ret == 0){
763
avahi_simple_poll_quit(mc->simple_poll);
1708
avahi_simple_poll_quit(simple_poll);
1709
} else {
1710
if(not add_server(ip, (in_port_t)port, interface,
1711
avahi_proto_to_af(proto),
1712
&((mandos_context*)mc)->current_server)){
1713
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1714
" list\n", name);
1715
}
764
1716
}
765
1717
}
766
1718
}
767
1719
avahi_s_service_resolver_free(r);
768
1720
}
769
1721
770
static void browse_callback( AvahiSServiceBrowser *b,
771
AvahiIfIndex interface,
772
AvahiProtocol protocol,
773
AvahiBrowserEvent event,
774
const char *name,
775
const char *type,
776
const char *domain,
777
AVAHI_GCC_UNUSED AvahiLookupResultFlags
778
flags,
779
void* userdata) {
780
mandos_context *mc = userdata;
781
assert(b);
1722
static void browse_callback(AvahiSServiceBrowser *b,
1723
AvahiIfIndex interface,
1724
AvahiProtocol protocol,
1725
AvahiBrowserEvent event,
1726
const char *name,
1727
const char *type,
1728
const char *domain,
1729
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1730
flags,
1731
void *mc){
1732
if(b == NULL){
1733
return;
1734
}
782
1735
783
1736
/* Called whenever a new services becomes available on the LAN or
784
1737
is removed from the LAN */
785
1738
786
switch(event) {
1739
if(quit_now){
1740
return;
1741
}
1742
1743
switch(event){
787
1744
default:
788
1745
case AVAHI_BROWSER_FAILURE:
789
1746
790
fprintf(stderr, "(Avahi browser) %s\n",
791
avahi_strerror(avahi_server_errno(mc->server)));
792
avahi_simple_poll_quit(mc->simple_poll);
1747
fprintf_plus(stderr, "(Avahi browser) %s\n",
1748
avahi_strerror(avahi_server_errno
1749
(((mandos_context*)mc)->server)));
1750
avahi_simple_poll_quit(simple_poll);
793
1751
return;
794
1752
795
1753
case AVAHI_BROWSER_NEW:
798
1756
the callback function is called the Avahi server will free the
799
1757
resolver for us. */
800
1758
801
if(!(avahi_s_service_resolver_new(mc->server, interface,
802
protocol, name, type, domain,
803
AVAHI_PROTO_INET6, 0,
804
resolve_callback, mc)))
805
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
806
name, avahi_strerror(avahi_server_errno(mc->server)));
1759
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1760
interface, protocol, name, type,
1761
domain, protocol, 0,
1762
resolve_callback, mc) == NULL)
1763
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1764
" %s\n", name,
1765
avahi_strerror(avahi_server_errno
1766
(((mandos_context*)mc)->server)));
807
1767
break;
808
1768
809
1769
case AVAHI_BROWSER_REMOVE:
812
1772
case AVAHI_BROWSER_ALL_FOR_NOW:
813
1773
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
1774
if(debug){
815
fprintf(stderr, "No Mandos server found, still searching...\n");
1775
fprintf_plus(stderr, "No Mandos server found, still"
1776
" searching...\n");
816
1777
}
817
1778
break;
818
1779
}
819
1780
}
820
1781
1782
/* Signal handler that stops main loop after SIGTERM */
1783
static void handle_sigterm(int sig){
1784
if(quit_now){
1785
return;
1786
}
1787
quit_now = 1;
1788
signal_received = sig;
1789
int old_errno = errno;
1790
/* set main loop to exit */
1791
if(simple_poll != NULL){
1792
avahi_simple_poll_quit(simple_poll);
1793
}
1794
errno = old_errno;
1795
}
1796
1797
__attribute__((nonnull, warn_unused_result))
1798
bool get_flags(const char *ifname, struct ifreq *ifr){
1799
int ret;
1800
int old_errno;
1801
1802
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1803
if(s < 0){
1804
old_errno = errno;
1805
perror_plus("socket");
1806
errno = old_errno;
1807
return false;
1808
}
1809
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1810
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1811
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1812
if(ret == -1){
1813
if(debug){
1814
old_errno = errno;
1815
perror_plus("ioctl SIOCGIFFLAGS");
1816
errno = old_errno;
1817
}
1818
if((close(s) == -1) and debug){
1819
old_errno = errno;
1820
perror_plus("close");
1821
errno = old_errno;
1822
}
1823
return false;
1824
}
1825
if((close(s) == -1) and debug){
1826
old_errno = errno;
1827
perror_plus("close");
1828
errno = old_errno;
1829
}
1830
return true;
1831
}
1832
1833
__attribute__((nonnull, warn_unused_result))
1834
bool good_flags(const char *ifname, const struct ifreq *ifr){
1835
1836
/* Reject the loopback device */
1837
if(ifr->ifr_flags & IFF_LOOPBACK){
1838
if(debug){
1839
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1840
ifname);
1841
}
1842
return false;
1843
}
1844
/* Accept point-to-point devices only if connect_to is specified */
1845
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1846
if(debug){
1847
fprintf_plus(stderr, "Accepting point-to-point interface"
1848
" \"%s\"\n", ifname);
1849
}
1850
return true;
1851
}
1852
/* Otherwise, reject non-broadcast-capable devices */
1853
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1854
if(debug){
1855
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1856
" \"%s\"\n", ifname);
1857
}
1858
return false;
1859
}
1860
/* Reject non-ARP interfaces (including dummy interfaces) */
1861
if(ifr->ifr_flags & IFF_NOARP){
1862
if(debug){
1863
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1864
ifname);
1865
}
1866
return false;
1867
}
1868
1869
/* Accept this device */
1870
if(debug){
1871
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1872
}
1873
return true;
1874
}
1875
1876
/*
1877
* This function determines if a directory entry in /sys/class/net
1878
* corresponds to an acceptable network device.
1879
* (This function is passed to scandir(3) as a filter function.)
1880
*/
1881
__attribute__((nonnull, warn_unused_result))
1882
int good_interface(const struct dirent *if_entry){
1883
if(if_entry->d_name[0] == '.'){
1884
return 0;
1885
}
1886
1887
struct ifreq ifr;
1888
if(not get_flags(if_entry->d_name, &ifr)){
1889
if(debug){
1890
fprintf_plus(stderr, "Failed to get flags for interface "
1891
"\"%s\"\n", if_entry->d_name);
1892
}
1893
return 0;
1894
}
1895
1896
if(not good_flags(if_entry->d_name, &ifr)){
1897
return 0;
1898
}
1899
return 1;
1900
}
1901
1902
/*
1903
* This function determines if a network interface is up.
1904
*/
1905
__attribute__((nonnull, warn_unused_result))
1906
bool interface_is_up(const char *interface){
1907
struct ifreq ifr;
1908
if(not get_flags(interface, &ifr)){
1909
if(debug){
1910
fprintf_plus(stderr, "Failed to get flags for interface "
1911
"\"%s\"\n", interface);
1912
}
1913
return false;
1914
}
1915
1916
return (bool)(ifr.ifr_flags & IFF_UP);
1917
}
1918
1919
/*
1920
* This function determines if a network interface is running
1921
*/
1922
__attribute__((nonnull, warn_unused_result))
1923
bool interface_is_running(const char *interface){
1924
struct ifreq ifr;
1925
if(not get_flags(interface, &ifr)){
1926
if(debug){
1927
fprintf_plus(stderr, "Failed to get flags for interface "
1928
"\"%s\"\n", interface);
1929
}
1930
return false;
1931
}
1932
1933
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1934
}
1935
1936
__attribute__((nonnull, pure, warn_unused_result))
1937
int notdotentries(const struct dirent *direntry){
1938
/* Skip "." and ".." */
1939
if(direntry->d_name[0] == '.'
1940
and (direntry->d_name[1] == '\0'
1941
or (direntry->d_name[1] == '.'
1942
and direntry->d_name[2] == '\0'))){
1943
return 0;
1944
}
1945
return 1;
1946
}
1947
1948
/* Is this directory entry a runnable program? */
1949
__attribute__((nonnull, warn_unused_result))
1950
int runnable_hook(const struct dirent *direntry){
1951
int ret;
1952
size_t sret;
1953
struct stat st;
1954
1955
if((direntry->d_name)[0] == '\0'){
1956
/* Empty name? */
1957
return 0;
1958
}
1959
1960
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1961
"abcdefghijklmnopqrstuvwxyz"
1962
"0123456789"
1963
"_.-");
1964
if((direntry->d_name)[sret] != '\0'){
1965
/* Contains non-allowed characters */
1966
if(debug){
1967
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1968
direntry->d_name);
1969
}
1970
return 0;
1971
}
1972
1973
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1974
if(ret == -1){
1975
if(debug){
1976
perror_plus("Could not stat hook");
1977
}
1978
return 0;
1979
}
1980
if(not (S_ISREG(st.st_mode))){
1981
/* Not a regular file */
1982
if(debug){
1983
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1984
direntry->d_name);
1985
}
1986
return 0;
1987
}
1988
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1989
/* Not executable */
1990
if(debug){
1991
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1992
direntry->d_name);
1993
}
1994
return 0;
1995
}
1996
if(debug){
1997
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1998
direntry->d_name);
1999
}
2000
return 1;
2001
}
2002
2003
__attribute__((nonnull, warn_unused_result))
2004
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
2005
mandos_context *mc){
2006
int ret;
2007
struct timespec now;
2008
struct timespec waited_time;
2009
intmax_t block_time;
2010
2011
while(true){
2012
if(mc->current_server == NULL){
2013
if(debug){
2014
fprintf_plus(stderr, "Wait until first server is found."
2015
" No timeout!\n");
2016
}
2017
ret = avahi_simple_poll_iterate(s, -1);
2018
} else {
2019
if(debug){
2020
fprintf_plus(stderr, "Check current_server if we should run"
2021
" it, or wait\n");
2022
}
2023
/* the current time */
2024
ret = clock_gettime(CLOCK_MONOTONIC, &now);
2025
if(ret == -1){
2026
perror_plus("clock_gettime");
2027
return -1;
2028
}
2029
/* Calculating in ms how long time between now and server
2030
who we visted longest time ago. Now - last seen. */
2031
waited_time.tv_sec = (now.tv_sec
2032
- mc->current_server->last_seen.tv_sec);
2033
waited_time.tv_nsec = (now.tv_nsec
2034
- mc->current_server->last_seen.tv_nsec);
2035
/* total time is 10s/10,000ms.
2036
Converting to s from ms by dividing by 1,000,
2037
and ns to ms by dividing by 1,000,000. */
2038
block_time = ((retry_interval
2039
- ((intmax_t)waited_time.tv_sec * 1000))
2040
- ((intmax_t)waited_time.tv_nsec / 1000000));
2041
2042
if(debug){
2043
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
2044
block_time);
2045
}
2046
2047
if(block_time <= 0){
2048
ret = start_mandos_communication(mc->current_server->ip,
2049
mc->current_server->port,
2050
mc->current_server->if_index,
2051
mc->current_server->af, mc);
2052
if(ret == 0){
2053
avahi_simple_poll_quit(s);
2054
return 0;
2055
}
2056
ret = clock_gettime(CLOCK_MONOTONIC,
2057
&mc->current_server->last_seen);
2058
if(ret == -1){
2059
perror_plus("clock_gettime");
2060
return -1;
2061
}
2062
mc->current_server = mc->current_server->next;
2063
block_time = 0; /* Call avahi to find new Mandos
2064
servers, but don't block */
2065
}
2066
2067
ret = avahi_simple_poll_iterate(s, (int)block_time);
2068
}
2069
if(ret != 0){
2070
if(ret > 0 or errno != EINTR){
2071
return (ret != 1) ? ret : 0;
2072
}
2073
}
2074
}
2075
}
2076
2077
__attribute__((nonnull))
2078
void run_network_hooks(const char *mode, const char *interface,
2079
const float delay){
2080
struct dirent **direntries = NULL;
2081
if(hookdir_fd == -1){
2082
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2083
| O_CLOEXEC);
2084
if(hookdir_fd == -1){
2085
if(errno == ENOENT){
2086
if(debug){
2087
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2088
" found\n", hookdir);
2089
}
2090
} else {
2091
perror_plus("open");
2092
}
2093
return;
2094
}
2095
}
2096
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2097
if(devnull == -1){
2098
perror_plus("open(\"/dev/null\", O_RDONLY)");
2099
return;
2100
}
2101
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2102
runnable_hook, alphasort);
2103
if(numhooks == -1){
2104
perror_plus("scandir");
2105
close(devnull);
2106
return;
2107
}
2108
struct dirent *direntry;
2109
int ret;
2110
for(int i = 0; i < numhooks; i++){
2111
direntry = direntries[i];
2112
if(debug){
2113
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2114
direntry->d_name);
2115
}
2116
pid_t hook_pid = fork();
2117
if(hook_pid == 0){
2118
/* Child */
2119
/* Raise privileges */
2120
errno = raise_privileges_permanently();
2121
if(errno != 0){
2122
perror_plus("Failed to raise privileges");
2123
_exit(EX_NOPERM);
2124
}
2125
/* Set group */
2126
errno = 0;
2127
ret = setgid(0);
2128
if(ret == -1){
2129
perror_plus("setgid");
2130
_exit(EX_NOPERM);
2131
}
2132
/* Reset supplementary groups */
2133
errno = 0;
2134
ret = setgroups(0, NULL);
2135
if(ret == -1){
2136
perror_plus("setgroups");
2137
_exit(EX_NOPERM);
2138
}
2139
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2140
if(ret == -1){
2141
perror_plus("setenv");
2142
_exit(EX_OSERR);
2143
}
2144
ret = setenv("DEVICE", interface, 1);
2145
if(ret == -1){
2146
perror_plus("setenv");
2147
_exit(EX_OSERR);
2148
}
2149
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2150
if(ret == -1){
2151
perror_plus("setenv");
2152
_exit(EX_OSERR);
2153
}
2154
ret = setenv("MODE", mode, 1);
2155
if(ret == -1){
2156
perror_plus("setenv");
2157
_exit(EX_OSERR);
2158
}
2159
char *delaystring;
2160
ret = asprintf(&delaystring, "%f", (double)delay);
2161
if(ret == -1){
2162
perror_plus("asprintf");
2163
_exit(EX_OSERR);
2164
}
2165
ret = setenv("DELAY", delaystring, 1);
2166
if(ret == -1){
2167
free(delaystring);
2168
perror_plus("setenv");
2169
_exit(EX_OSERR);
2170
}
2171
free(delaystring);
2172
if(connect_to != NULL){
2173
ret = setenv("CONNECT", connect_to, 1);
2174
if(ret == -1){
2175
perror_plus("setenv");
2176
_exit(EX_OSERR);
2177
}
2178
}
2179
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2180
direntry->d_name,
2181
O_RDONLY));
2182
if(hook_fd == -1){
2183
perror_plus("openat");
2184
_exit(EXIT_FAILURE);
2185
}
2186
if(close(hookdir_fd) == -1){
2187
perror_plus("close");
2188
_exit(EXIT_FAILURE);
2189
}
2190
ret = dup2(devnull, STDIN_FILENO);
2191
if(ret == -1){
2192
perror_plus("dup2(devnull, STDIN_FILENO)");
2193
_exit(EX_OSERR);
2194
}
2195
ret = close(devnull);
2196
if(ret == -1){
2197
perror_plus("close");
2198
_exit(EX_OSERR);
2199
}
2200
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2201
if(ret == -1){
2202
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2203
_exit(EX_OSERR);
2204
}
2205
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2206
environ) == -1){
2207
perror_plus("fexecve");
2208
_exit(EXIT_FAILURE);
2209
}
2210
} else {
2211
if(hook_pid == -1){
2212
perror_plus("fork");
2213
free(direntry);
2214
continue;
2215
}
2216
int status;
2217
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2218
perror_plus("waitpid");
2219
free(direntry);
2220
continue;
2221
}
2222
if(WIFEXITED(status)){
2223
if(WEXITSTATUS(status) != 0){
2224
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2225
" with status %d\n", direntry->d_name,
2226
WEXITSTATUS(status));
2227
free(direntry);
2228
continue;
2229
}
2230
} else if(WIFSIGNALED(status)){
2231
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2232
" signal %d\n", direntry->d_name,
2233
WTERMSIG(status));
2234
free(direntry);
2235
continue;
2236
} else {
2237
fprintf_plus(stderr, "Warning: network hook \"%s\""
2238
" crashed\n", direntry->d_name);
2239
free(direntry);
2240
continue;
2241
}
2242
}
2243
if(debug){
2244
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2245
direntry->d_name);
2246
}
2247
free(direntry);
2248
}
2249
free(direntries);
2250
if(close(hookdir_fd) == -1){
2251
perror_plus("close");
2252
} else {
2253
hookdir_fd = -1;
2254
}
2255
close(devnull);
2256
}
2257
2258
__attribute__((nonnull, warn_unused_result))
2259
int bring_up_interface(const char *const interface,
2260
const float delay){
2261
int old_errno = errno;
2262
int ret;
2263
struct ifreq network;
2264
unsigned int if_index = if_nametoindex(interface);
2265
if(if_index == 0){
2266
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2267
errno = old_errno;
2268
return ENXIO;
2269
}
2270
2271
if(quit_now){
2272
errno = old_errno;
2273
return EINTR;
2274
}
2275
2276
if(not interface_is_up(interface)){
2277
int ret_errno = 0;
2278
int ioctl_errno = 0;
2279
if(not get_flags(interface, &network)){
2280
ret_errno = errno;
2281
fprintf_plus(stderr, "Failed to get flags for interface "
2282
"\"%s\"\n", interface);
2283
errno = old_errno;
2284
return ret_errno;
2285
}
2286
network.ifr_flags |= IFF_UP; /* set flag */
2287
2288
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2289
if(sd == -1){
2290
ret_errno = errno;
2291
perror_plus("socket");
2292
errno = old_errno;
2293
return ret_errno;
2294
}
2295
2296
if(quit_now){
2297
ret = close(sd);
2298
if(ret == -1){
2299
perror_plus("close");
2300
}
2301
errno = old_errno;
2302
return EINTR;
2303
}
2304
2305
if(debug){
2306
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2307
interface);
2308
}
2309
2310
/* Raise privileges */
2311
ret_errno = raise_privileges();
2312
if(ret_errno != 0){
2313
errno = ret_errno;
2314
perror_plus("Failed to raise privileges");
2315
}
2316
2317
#ifdef __linux__
2318
int ret_linux;
2319
bool restore_loglevel = false;
2320
if(ret_errno == 0){
2321
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2322
messages about the network interface to mess up the prompt */
2323
ret_linux = klogctl(8, NULL, 5);
2324
if(ret_linux == -1){
2325
perror_plus("klogctl");
2326
} else {
2327
restore_loglevel = true;
2328
}
2329
}
2330
#endif /* __linux__ */
2331
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2332
ioctl_errno = errno;
2333
#ifdef __linux__
2334
if(restore_loglevel){
2335
ret_linux = klogctl(7, NULL, 0);
2336
if(ret_linux == -1){
2337
perror_plus("klogctl");
2338
}
2339
}
2340
#endif /* __linux__ */
2341
2342
/* If raise_privileges() succeeded above */
2343
if(ret_errno == 0){
2344
/* Lower privileges */
2345
ret_errno = lower_privileges();
2346
if(ret_errno != 0){
2347
errno = ret_errno;
2348
perror_plus("Failed to lower privileges");
2349
}
2350
}
2351
2352
/* Close the socket */
2353
ret = close(sd);
2354
if(ret == -1){
2355
perror_plus("close");
2356
}
2357
2358
if(ret_setflags == -1){
2359
errno = ioctl_errno;
2360
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2361
errno = old_errno;
2362
return ioctl_errno;
2363
}
2364
} else if(debug){
2365
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2366
interface);
2367
}
2368
2369
/* Sleep checking until interface is running.
2370
Check every 0.25s, up to total time of delay */
2371
for(int i = 0; i < delay * 4; i++){
2372
if(interface_is_running(interface)){
2373
break;
2374
}
2375
struct timespec sleeptime = { .tv_nsec = 250000000 };
2376
ret = nanosleep(&sleeptime, NULL);
2377
if(ret == -1 and errno != EINTR){
2378
perror_plus("nanosleep");
2379
}
2380
}
2381
2382
errno = old_errno;
2383
return 0;
2384
}
2385
2386
__attribute__((nonnull, warn_unused_result))
2387
int take_down_interface(const char *const interface){
2388
int old_errno = errno;
2389
struct ifreq network;
2390
unsigned int if_index = if_nametoindex(interface);
2391
if(if_index == 0){
2392
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2393
errno = old_errno;
2394
return ENXIO;
2395
}
2396
if(interface_is_up(interface)){
2397
int ret_errno = 0;
2398
int ioctl_errno = 0;
2399
if(not get_flags(interface, &network) and debug){
2400
ret_errno = errno;
2401
fprintf_plus(stderr, "Failed to get flags for interface "
2402
"\"%s\"\n", interface);
2403
errno = old_errno;
2404
return ret_errno;
2405
}
2406
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2407
2408
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2409
if(sd == -1){
2410
ret_errno = errno;
2411
perror_plus("socket");
2412
errno = old_errno;
2413
return ret_errno;
2414
}
2415
2416
if(debug){
2417
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2418
interface);
2419
}
2420
2421
/* Raise privileges */
2422
ret_errno = raise_privileges();
2423
if(ret_errno != 0){
2424
errno = ret_errno;
2425
perror_plus("Failed to raise privileges");
2426
}
2427
2428
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2429
ioctl_errno = errno;
2430
2431
/* If raise_privileges() succeeded above */
2432
if(ret_errno == 0){
2433
/* Lower privileges */
2434
ret_errno = lower_privileges();
2435
if(ret_errno != 0){
2436
errno = ret_errno;
2437
perror_plus("Failed to lower privileges");
2438
}
2439
}
2440
2441
/* Close the socket */
2442
int ret = close(sd);
2443
if(ret == -1){
2444
perror_plus("close");
2445
}
2446
2447
if(ret_setflags == -1){
2448
errno = ioctl_errno;
2449
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2450
errno = old_errno;
2451
return ioctl_errno;
2452
}
2453
} else if(debug){
2454
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2455
interface);
2456
}
2457
2458
errno = old_errno;
2459
return 0;
2460
}
2461
821
2462
int main(int argc, char *argv[]){
822
AvahiSServiceBrowser *sb = NULL;
823
int error;
824
int ret;
825
intmax_t tmpmax;
826
int numchars;
827
int exitcode = EXIT_SUCCESS;
828
const char *interface = "eth0";
829
struct ifreq network;
830
int sd;
831
uid_t uid;
832
gid_t gid;
833
char *connect_to = NULL;
834
char tempdir[] = "/tmp/mandosXXXXXX";
835
bool tempdir_created = false;
836
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
837
const char *seckey = PATHDIR "/" SECKEY;
838
const char *pubkey = PATHDIR "/" PUBKEY;
839
840
mandos_context mc = { .simple_poll = NULL, .server = NULL,
841
.dh_bits = 1024, .priority = "SECURE256"
842
":!CTYPE-X.509:+CTYPE-OPENPGP" };
843
bool gnutls_initialized = false;
844
bool gpgme_initialized = false;
845
846
{
847
struct argp_option options[] = {
848
{ .name = "debug", .key = 128,
849
.doc = "Debug mode", .group = 3 },
850
{ .name = "connect", .key = 'c',
851
.arg = "ADDRESS:PORT",
852
.doc = "Connect directly to a specific Mandos server",
853
.group = 1 },
854
{ .name = "interface", .key = 'i',
855
.arg = "NAME",
856
.doc = "Interface that will be used to search for Mandos"
857
" servers",
858
.group = 1 },
859
{ .name = "seckey", .key = 's',
860
.arg = "FILE",
861
.doc = "OpenPGP secret key file base name",
862
.group = 1 },
863
{ .name = "pubkey", .key = 'p',
864
.arg = "FILE",
865
.doc = "OpenPGP public key file base name",
866
.group = 2 },
867
{ .name = "dh-bits", .key = 129,
868
.arg = "BITS",
869
.doc = "Bit length of the prime number used in the"
870
" Diffie-Hellman key exchange",
871
.group = 2 },
872
{ .name = "priority", .key = 130,
873
.arg = "STRING",
874
.doc = "GnuTLS priority string for the TLS handshake",
875
.group = 1 },
876
{ .name = NULL }
877
};
878
879
error_t parse_opt(int key, char *arg,
880
struct argp_state *state) {
881
switch(key) {
882
case 128: /* --debug */
883
debug = true;
884
break;
885
case 'c': /* --connect */
886
connect_to = arg;
887
break;
888
case 'i': /* --interface */
889
interface = arg;
890
break;
891
case 's': /* --seckey */
892
seckey = arg;
893
break;
894
case 'p': /* --pubkey */
895
pubkey = arg;
896
break;
897
case 129: /* --dh-bits */
898
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
899
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
900
or arg[numchars] != '\0'){
901
fprintf(stderr, "Bad number of DH bits\n");
902
exit(EXIT_FAILURE);
903
}
904
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
905
break;
906
case 130: /* --priority */
907
mc.priority = arg;
908
break;
909
case ARGP_KEY_ARG:
910
argp_usage(state);
911
case ARGP_KEY_END:
912
break;
913
default:
914
return ARGP_ERR_UNKNOWN;
915
}
916
return 0;
917
}
918
919
struct argp argp = { .options = options, .parser = parse_opt,
920
.args_doc = "",
921
.doc = "Mandos client -- Get and decrypt"
922
" passwords from a Mandos server" };
923
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
924
if(ret == ARGP_ERR_UNKNOWN){
925
fprintf(stderr, "Unknown error while parsing arguments\n");
926
exitcode = EXIT_FAILURE;
927
goto end;
928
}
929
}
930
931
/* If the interface is down, bring it up */
932
{
933
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
934
if(sd < 0) {
935
perror("socket");
936
exitcode = EXIT_FAILURE;
937
goto end;
938
}
939
strcpy(network.ifr_name, interface);
940
ret = ioctl(sd, SIOCGIFFLAGS, &network);
941
if(ret == -1){
942
perror("ioctl SIOCGIFFLAGS");
943
exitcode = EXIT_FAILURE;
944
goto end;
945
}
946
if((network.ifr_flags & IFF_UP) == 0){
947
network.ifr_flags |= IFF_UP;
948
ret = ioctl(sd, SIOCSIFFLAGS, &network);
949
if(ret == -1){
950
perror("ioctl SIOCSIFFLAGS");
951
exitcode = EXIT_FAILURE;
952
goto end;
953
}
954
}
955
ret = (int)TEMP_FAILURE_RETRY(close(sd));
956
if(ret == -1){
957
perror("close");
958
}
959
}
960
961
uid = getuid();
962
gid = getgid();
963
964
ret = setuid(uid);
965
if(ret == -1){
966
perror("setuid");
967
}
968
969
setgid(gid);
970
if(ret == -1){
971
perror("setgid");
972
}
973
974
ret = init_gnutls_global(&mc, pubkey, seckey);
975
if(ret == -1){
976
fprintf(stderr, "init_gnutls_global failed\n");
977
exitcode = EXIT_FAILURE;
978
goto end;
979
} else {
980
gnutls_initialized = true;
981
}
982
983
if(mkdtemp(tempdir) == NULL){
984
perror("mkdtemp");
985
goto end;
986
}
987
tempdir_created = true;
988
989
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
990
fprintf(stderr, "init_gpgme failed\n");
991
exitcode = EXIT_FAILURE;
992
goto end;
993
} else {
994
gpgme_initialized = true;
995
}
996
997
if_index = (AvahiIfIndex) if_nametoindex(interface);
998
if(if_index == 0){
999
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1000
exitcode = EXIT_FAILURE;
1001
goto end;
1002
}
1003
1004
if(connect_to != NULL){
1005
/* Connect directly, do not use Zeroconf */
1006
/* (Mainly meant for debugging) */
1007
char *address = strrchr(connect_to, ':');
1008
if(address == NULL){
1009
fprintf(stderr, "No colon in address\n");
1010
exitcode = EXIT_FAILURE;
1011
goto end;
1012
}
1013
uint16_t port;
1014
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1015
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1016
or address[numchars+1] != '\0'){
1017
fprintf(stderr, "Bad port number\n");
1018
exitcode = EXIT_FAILURE;
1019
goto end;
1020
}
1021
port = (uint16_t)tmpmax;
1022
*address = '\0';
1023
address = connect_to;
1024
ret = start_mandos_communication(address, port, if_index, &mc);
1025
if(ret < 0){
1026
exitcode = EXIT_FAILURE;
1027
} else {
1028
exitcode = EXIT_SUCCESS;
1029
}
1030
goto end;
1031
}
1032
1033
if(not debug){
1034
avahi_set_log_function(empty_log);
1035
}
1036
1037
/* Initialize the pseudo-RNG for Avahi */
1038
srand((unsigned int) time(NULL));
1039
1040
/* Allocate main Avahi loop object */
1041
mc.simple_poll = avahi_simple_poll_new();
1042
if(mc.simple_poll == NULL) {
1043
fprintf(stderr, "Avahi: Failed to create simple poll"
1044
" object.\n");
1045
exitcode = EXIT_FAILURE;
1046
goto end;
1047
}
1048
1049
{
1050
AvahiServerConfig config;
1051
/* Do not publish any local Zeroconf records */
1052
avahi_server_config_init(&config);
1053
config.publish_hinfo = 0;
1054
config.publish_addresses = 0;
1055
config.publish_workstation = 0;
1056
config.publish_domain = 0;
1057
1058
/* Allocate a new server */
1059
mc.server = avahi_server_new(avahi_simple_poll_get
1060
(mc.simple_poll), &config, NULL,
1061
NULL, &error);
1062
1063
/* Free the Avahi configuration data */
1064
avahi_server_config_free(&config);
1065
}
1066
1067
/* Check if creating the Avahi server object succeeded */
1068
if(mc.server == NULL) {
1069
fprintf(stderr, "Failed to create Avahi server: %s\n",
1070
avahi_strerror(error));
1071
exitcode = EXIT_FAILURE;
1072
goto end;
1073
}
1074
1075
/* Create the Avahi service browser */
1076
sb = avahi_s_service_browser_new(mc.server, if_index,
1077
AVAHI_PROTO_INET6,
1078
"_mandos._tcp", NULL, 0,
1079
browse_callback, &mc);
1080
if(sb == NULL) {
1081
fprintf(stderr, "Failed to create service browser: %s\n",
1082
avahi_strerror(avahi_server_errno(mc.server)));
1083
exitcode = EXIT_FAILURE;
1084
goto end;
1085
}
1086
1087
/* Run the main loop */
1088
2463
mandos_context mc = { .server = NULL, .dh_bits = 0,
2464
#if GNUTLS_VERSION_NUMBER >= 0x030606
2465
.priority = "SECURE128:!CTYPE-X.509"
2466
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2467
":%PROFILE_ULTRA",
2468
#elif GNUTLS_VERSION_NUMBER < 0x030600
2469
.priority = "SECURE256:!CTYPE-X.509"
2470
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2471
#else
2472
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2473
#endif
2474
.current_server = NULL, .interfaces = NULL,
2475
.interfaces_size = 0 };
2476
AvahiSServiceBrowser *sb = NULL;
2477
error_t ret_errno;
2478
int ret;
2479
intmax_t tmpmax;
2480
char *tmp;
2481
int exitcode = EXIT_SUCCESS;
2482
char *interfaces_to_take_down = NULL;
2483
size_t interfaces_to_take_down_size = 0;
2484
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2485
char old_tempdir[] = "/tmp/mandosXXXXXX";
2486
char *tempdir = NULL;
2487
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2488
const char *seckey = PATHDIR "/" SECKEY;
2489
const char *pubkey = PATHDIR "/" PUBKEY;
2490
#if GNUTLS_VERSION_NUMBER >= 0x030606
2491
const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;
2492
const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;
2493
#endif
2494
const char *dh_params_file = NULL;
2495
char *interfaces_hooks = NULL;
2496
2497
bool gnutls_initialized = false;
2498
bool gpgme_initialized = false;
2499
float delay = 2.5f;
2500
double retry_interval = 10; /* 10s between trying a server and
2501
retrying the same server again */
2502
2503
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2504
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2505
2506
uid = getuid();
2507
gid = getgid();
2508
2509
/* Lower any group privileges we might have, just to be safe */
2510
errno = 0;
2511
ret = setgid(gid);
2512
if(ret == -1){
2513
perror_plus("setgid");
2514
}
2515
2516
/* Lower user privileges (temporarily) */
2517
errno = 0;
2518
ret = seteuid(uid);
2519
if(ret == -1){
2520
perror_plus("seteuid");
2521
}
2522
2523
if(quit_now){
2524
goto end;
2525
}
2526
2527
{
2528
struct argp_option options[] = {
2529
{ .name = "debug", .key = 128,
2530
.doc = "Debug mode", .group = 3 },
2531
{ .name = "connect", .key = 'c',
2532
.arg = "ADDRESS:PORT",
2533
.doc = "Connect directly to a specific Mandos server",
2534
.group = 1 },
2535
{ .name = "interface", .key = 'i',
2536
.arg = "NAME",
2537
.doc = "Network interface that will be used to search for"
2538
" Mandos servers",
2539
.group = 1 },
2540
{ .name = "seckey", .key = 's',
2541
.arg = "FILE",
2542
.doc = "OpenPGP secret key file base name",
2543
.group = 1 },
2544
{ .name = "pubkey", .key = 'p',
2545
.arg = "FILE",
2546
.doc = "OpenPGP public key file base name",
2547
.group = 1 },
2548
{ .name = "tls-privkey", .key = 't',
2549
.arg = "FILE",
2550
#if GNUTLS_VERSION_NUMBER >= 0x030606
2551
.doc = "TLS private key file base name",
2552
#else
2553
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2554
#endif
2555
.group = 1 },
2556
{ .name = "tls-pubkey", .key = 'T',
2557
.arg = "FILE",
2558
#if GNUTLS_VERSION_NUMBER >= 0x030606
2559
.doc = "TLS public key file base name",
2560
#else
2561
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2562
#endif
2563
.group = 1 },
2564
{ .name = "dh-bits", .key = 129,
2565
.arg = "BITS",
2566
.doc = "Bit length of the prime number used in the"
2567
" Diffie-Hellman key exchange",
2568
.group = 2 },
2569
{ .name = "dh-params", .key = 134,
2570
.arg = "FILE",
2571
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2572
" for the Diffie-Hellman key exchange",
2573
.group = 2 },
2574
{ .name = "priority", .key = 130,
2575
.arg = "STRING",
2576
.doc = "GnuTLS priority string for the TLS handshake",
2577
.group = 1 },
2578
{ .name = "delay", .key = 131,
2579
.arg = "SECONDS",
2580
.doc = "Maximum delay to wait for interface startup",
2581
.group = 2 },
2582
{ .name = "retry", .key = 132,
2583
.arg = "SECONDS",
2584
.doc = "Retry interval used when denied by the Mandos server",
2585
.group = 2 },
2586
{ .name = "network-hook-dir", .key = 133,
2587
.arg = "DIR",
2588
.doc = "Directory where network hooks are located",
2589
.group = 2 },
2590
/*
2591
* These reproduce what we would get without ARGP_NO_HELP
2592
*/
2593
{ .name = "help", .key = '?',
2594
.doc = "Give this help list", .group = -1 },
2595
{ .name = "usage", .key = -3,
2596
.doc = "Give a short usage message", .group = -1 },
2597
{ .name = "version", .key = 'V',
2598
.doc = "Print program version", .group = -1 },
2599
{ .name = NULL }
2600
};
2601
2602
error_t parse_opt(int key, char *arg,
2603
struct argp_state *state){
2604
errno = 0;
2605
switch(key){
2606
case 128: /* --debug */
2607
debug = true;
2608
break;
2609
case 'c': /* --connect */
2610
connect_to = arg;
2611
break;
2612
case 'i': /* --interface */
2613
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2614
arg, (int)',');
2615
if(ret_errno != 0){
2616
argp_error(state, "%s", strerror(ret_errno));
2617
}
2618
break;
2619
case 's': /* --seckey */
2620
seckey = arg;
2621
break;
2622
case 'p': /* --pubkey */
2623
pubkey = arg;
2624
break;
2625
case 't': /* --tls-privkey */
2626
#if GNUTLS_VERSION_NUMBER >= 0x030606
2627
tls_privkey = arg;
2628
#endif
2629
break;
2630
case 'T': /* --tls-pubkey */
2631
#if GNUTLS_VERSION_NUMBER >= 0x030606
2632
tls_pubkey = arg;
2633
#endif
2634
break;
2635
case 129: /* --dh-bits */
2636
errno = 0;
2637
tmpmax = strtoimax(arg, &tmp, 10);
2638
if(errno != 0 or tmp == arg or *tmp != '\0'
2639
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2640
argp_error(state, "Bad number of DH bits");
2641
}
2642
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2643
break;
2644
case 134: /* --dh-params */
2645
dh_params_file = arg;
2646
break;
2647
case 130: /* --priority */
2648
mc.priority = arg;
2649
break;
2650
case 131: /* --delay */
2651
errno = 0;
2652
delay = strtof(arg, &tmp);
2653
if(errno != 0 or tmp == arg or *tmp != '\0'){
2654
argp_error(state, "Bad delay");
2655
}
2656
case 132: /* --retry */
2657
errno = 0;
2658
retry_interval = strtod(arg, &tmp);
2659
if(errno != 0 or tmp == arg or *tmp != '\0'
2660
or (retry_interval * 1000) > INT_MAX
2661
or retry_interval < 0){
2662
argp_error(state, "Bad retry interval");
2663
}
2664
break;
2665
case 133: /* --network-hook-dir */
2666
hookdir = arg;
2667
break;
2668
/*
2669
* These reproduce what we would get without ARGP_NO_HELP
2670
*/
2671
case '?': /* --help */
2672
argp_state_help(state, state->out_stream,
2673
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2674
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2675
__builtin_unreachable();
2676
case -3: /* --usage */
2677
argp_state_help(state, state->out_stream,
2678
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2679
__builtin_unreachable();
2680
case 'V': /* --version */
2681
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2682
exit(argp_err_exit_status);
2683
break;
2684
default:
2685
return ARGP_ERR_UNKNOWN;
2686
}
2687
return errno;
2688
}
2689
2690
struct argp argp = { .options = options, .parser = parse_opt,
2691
.args_doc = "",
2692
.doc = "Mandos client -- Get and decrypt"
2693
" passwords from a Mandos server" };
2694
ret_errno = argp_parse(&argp, argc, argv,
2695
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2696
switch(ret_errno){
2697
case 0:
2698
break;
2699
case ENOMEM:
2700
default:
2701
errno = ret_errno;
2702
perror_plus("argp_parse");
2703
exitcode = EX_OSERR;
2704
goto end;
2705
case EINVAL:
2706
exitcode = EX_USAGE;
2707
goto end;
2708
}
2709
}
2710
2711
{
2712
/* Work around Debian bug #633582:
2713
<https://bugs.debian.org/633582> */
2714
2715
/* Re-raise privileges */
2716
ret = raise_privileges();
2717
if(ret != 0){
2718
errno = ret;
2719
perror_plus("Failed to raise privileges");
2720
} else {
2721
struct stat st;
2722
2723
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2724
int seckey_fd = open(seckey, O_RDONLY);
2725
if(seckey_fd == -1){
2726
perror_plus("open");
2727
} else {
2728
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2729
if(ret == -1){
2730
perror_plus("fstat");
2731
} else {
2732
if(S_ISREG(st.st_mode)
2733
and st.st_uid == 0 and st.st_gid == 0){
2734
ret = fchown(seckey_fd, uid, gid);
2735
if(ret == -1){
2736
perror_plus("fchown");
2737
}
2738
}
2739
}
2740
close(seckey_fd);
2741
}
2742
}
2743
2744
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2745
int pubkey_fd = open(pubkey, O_RDONLY);
2746
if(pubkey_fd == -1){
2747
perror_plus("open");
2748
} else {
2749
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2750
if(ret == -1){
2751
perror_plus("fstat");
2752
} else {
2753
if(S_ISREG(st.st_mode)
2754
and st.st_uid == 0 and st.st_gid == 0){
2755
ret = fchown(pubkey_fd, uid, gid);
2756
if(ret == -1){
2757
perror_plus("fchown");
2758
}
2759
}
2760
}
2761
close(pubkey_fd);
2762
}
2763
}
2764
2765
if(dh_params_file != NULL
2766
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2767
int dhparams_fd = open(dh_params_file, O_RDONLY);
2768
if(dhparams_fd == -1){
2769
perror_plus("open");
2770
} else {
2771
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2772
if(ret == -1){
2773
perror_plus("fstat");
2774
} else {
2775
if(S_ISREG(st.st_mode)
2776
and st.st_uid == 0 and st.st_gid == 0){
2777
ret = fchown(dhparams_fd, uid, gid);
2778
if(ret == -1){
2779
perror_plus("fchown");
2780
}
2781
}
2782
}
2783
close(dhparams_fd);
2784
}
2785
}
2786
2787
/* Lower privileges */
2788
ret = lower_privileges();
2789
if(ret != 0){
2790
errno = ret;
2791
perror_plus("Failed to lower privileges");
2792
}
2793
}
2794
}
2795
2796
/* Remove invalid interface names (except "none") */
2797
{
2798
char *interface = NULL;
2799
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2800
interface))){
2801
if(strcmp(interface, "none") != 0
2802
and if_nametoindex(interface) == 0){
2803
if(interface[0] != '\0'){
2804
fprintf_plus(stderr, "Not using nonexisting interface"
2805
" \"%s\"\n", interface);
2806
}
2807
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2808
interface = NULL;
2809
}
2810
}
2811
}
2812
2813
/* Run network hooks */
2814
{
2815
if(mc.interfaces != NULL){
2816
interfaces_hooks = malloc(mc.interfaces_size);
2817
if(interfaces_hooks == NULL){
2818
perror_plus("malloc");
2819
goto end;
2820
}
2821
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2822
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2823
}
2824
run_network_hooks("start", interfaces_hooks != NULL ?
2825
interfaces_hooks : "", delay);
2826
}
2827
2828
if(not debug){
2829
avahi_set_log_function(empty_log);
2830
}
2831
2832
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2833
from the signal handler */
2834
/* Initialize the pseudo-RNG for Avahi */
2835
srand((unsigned int) time(NULL));
2836
simple_poll = avahi_simple_poll_new();
2837
if(simple_poll == NULL){
2838
fprintf_plus(stderr,
2839
"Avahi: Failed to create simple poll object.\n");
2840
exitcode = EX_UNAVAILABLE;
2841
goto end;
2842
}
2843
2844
sigemptyset(&sigterm_action.sa_mask);
2845
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2846
if(ret == -1){
2847
perror_plus("sigaddset");
2848
exitcode = EX_OSERR;
2849
goto end;
2850
}
2851
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2852
if(ret == -1){
2853
perror_plus("sigaddset");
2854
exitcode = EX_OSERR;
2855
goto end;
2856
}
2857
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2858
if(ret == -1){
2859
perror_plus("sigaddset");
2860
exitcode = EX_OSERR;
2861
goto end;
2862
}
2863
/* Need to check if the handler is SIG_IGN before handling:
2864
| [[info:libc:Initial Signal Actions]] |
2865
| [[info:libc:Basic Signal Handling]] |
2866
*/
2867
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2868
if(ret == -1){
2869
perror_plus("sigaction");
2870
return EX_OSERR;
2871
}
2872
if(old_sigterm_action.sa_handler != SIG_IGN){
2873
ret = sigaction(SIGINT, &sigterm_action, NULL);
2874
if(ret == -1){
2875
perror_plus("sigaction");
2876
exitcode = EX_OSERR;
2877
goto end;
2878
}
2879
}
2880
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2881
if(ret == -1){
2882
perror_plus("sigaction");
2883
return EX_OSERR;
2884
}
2885
if(old_sigterm_action.sa_handler != SIG_IGN){
2886
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2887
if(ret == -1){
2888
perror_plus("sigaction");
2889
exitcode = EX_OSERR;
2890
goto end;
2891
}
2892
}
2893
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2894
if(ret == -1){
2895
perror_plus("sigaction");
2896
return EX_OSERR;
2897
}
2898
if(old_sigterm_action.sa_handler != SIG_IGN){
2899
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2900
if(ret == -1){
2901
perror_plus("sigaction");
2902
exitcode = EX_OSERR;
2903
goto end;
2904
}
2905
}
2906
2907
/* If no interfaces were specified, make a list */
2908
if(mc.interfaces == NULL){
2909
struct dirent **direntries = NULL;
2910
/* Look for any good interfaces */
2911
ret = scandir(sys_class_net, &direntries, good_interface,
2912
alphasort);
2913
if(ret >= 1){
2914
/* Add all found interfaces to interfaces list */
2915
for(int i = 0; i < ret; ++i){
2916
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2917
direntries[i]->d_name);
2918
if(ret_errno != 0){
2919
errno = ret_errno;
2920
perror_plus("argz_add");
2921
free(direntries[i]);
2922
continue;
2923
}
2924
if(debug){
2925
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2926
direntries[i]->d_name);
2927
}
2928
free(direntries[i]);
2929
}
2930
free(direntries);
2931
} else {
2932
if(ret == 0){
2933
free(direntries);
2934
}
2935
fprintf_plus(stderr, "Could not find a network interface\n");
2936
exitcode = EXIT_FAILURE;
2937
goto end;
2938
}
2939
}
2940
2941
/* Bring up interfaces which are down, and remove any "none"s */
2942
{
2943
char *interface = NULL;
2944
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2945
interface))){
2946
/* If interface name is "none", stop bringing up interfaces.
2947
Also remove all instances of "none" from the list */
2948
if(strcmp(interface, "none") == 0){
2949
argz_delete(&mc.interfaces, &mc.interfaces_size,
2950
interface);
2951
interface = NULL;
2952
while((interface = argz_next(mc.interfaces,
2953
mc.interfaces_size, interface))){
2954
if(strcmp(interface, "none") == 0){
2955
argz_delete(&mc.interfaces, &mc.interfaces_size,
2956
interface);
2957
interface = NULL;
2958
}
2959
}
2960
break;
2961
}
2962
bool interface_was_up = interface_is_up(interface);
2963
errno = bring_up_interface(interface, delay);
2964
if(not interface_was_up){
2965
if(errno != 0){
2966
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2967
" %s\n", interface, strerror(errno));
2968
} else {
2969
errno = argz_add(&interfaces_to_take_down,
2970
&interfaces_to_take_down_size,
2971
interface);
2972
if(errno != 0){
2973
perror_plus("argz_add");
2974
}
2975
}
2976
}
2977
}
2978
if(debug and (interfaces_to_take_down == NULL)){
2979
fprintf_plus(stderr, "No interfaces were brought up\n");
2980
}
2981
}
2982
2983
/* If we only got one interface, explicitly use only that one */
2984
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
1089
2985
if(debug){
1090
fprintf(stderr, "Starting Avahi loop search\n");
1091
}
1092
1093
avahi_simple_poll_loop(mc.simple_poll);
1094
2986
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2987
mc.interfaces);
2988
}
2989
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2990
}
2991
2992
if(quit_now){
2993
goto end;
2994
}
2995
2996
#if GNUTLS_VERSION_NUMBER >= 0x030606
2997
ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);
2998
#elif GNUTLS_VERSION_NUMBER < 0x030600
2999
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
3000
#else
3001
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
3002
#endif
3003
if(ret == -1){
3004
fprintf_plus(stderr, "init_gnutls_global failed\n");
3005
exitcode = EX_UNAVAILABLE;
3006
goto end;
3007
} else {
3008
gnutls_initialized = true;
3009
}
3010
3011
if(quit_now){
3012
goto end;
3013
}
3014
3015
/* Try /run/tmp before /tmp */
3016
tempdir = mkdtemp(run_tempdir);
3017
if(tempdir == NULL and errno == ENOENT){
3018
if(debug){
3019
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
3020
run_tempdir, old_tempdir);
3021
}
3022
tempdir = mkdtemp(old_tempdir);
3023
}
3024
if(tempdir == NULL){
3025
perror_plus("mkdtemp");
3026
goto end;
3027
}
3028
3029
if(quit_now){
3030
goto end;
3031
}
3032
3033
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
3034
fprintf_plus(stderr, "init_gpgme failed\n");
3035
exitcode = EX_UNAVAILABLE;
3036
goto end;
3037
} else {
3038
gpgme_initialized = true;
3039
}
3040
3041
if(quit_now){
3042
goto end;
3043
}
3044
3045
if(connect_to != NULL){
3046
/* Connect directly, do not use Zeroconf */
3047
/* (Mainly meant for debugging) */
3048
char *address = strrchr(connect_to, ':');
3049
3050
if(address == NULL){
3051
fprintf_plus(stderr, "No colon in address\n");
3052
exitcode = EX_USAGE;
3053
goto end;
3054
}
3055
3056
if(quit_now){
3057
goto end;
3058
}
3059
3060
in_port_t port;
3061
errno = 0;
3062
tmpmax = strtoimax(address+1, &tmp, 10);
3063
if(errno != 0 or tmp == address+1 or *tmp != '\0'
3064
or tmpmax != (in_port_t)tmpmax){
3065
fprintf_plus(stderr, "Bad port number\n");
3066
exitcode = EX_USAGE;
3067
goto end;
3068
}
3069
3070
if(quit_now){
3071
goto end;
3072
}
3073
3074
port = (in_port_t)tmpmax;
3075
*address = '\0';
3076
/* Colon in address indicates IPv6 */
3077
int af;
3078
if(strchr(connect_to, ':') != NULL){
3079
af = AF_INET6;
3080
/* Accept [] around IPv6 address - see RFC 5952 */
3081
if(connect_to[0] == '[' and address[-1] == ']')
3082
{
3083
connect_to++;
3084
address[-1] = '\0';
3085
}
3086
} else {
3087
af = AF_INET;
3088
}
3089
address = connect_to;
3090
3091
if(quit_now){
3092
goto end;
3093
}
3094
3095
while(not quit_now){
3096
ret = start_mandos_communication(address, port, if_index, af,
3097
&mc);
3098
if(quit_now or ret == 0){
3099
break;
3100
}
3101
if(debug){
3102
fprintf_plus(stderr, "Retrying in %d seconds\n",
3103
(int)retry_interval);
3104
}
3105
sleep((unsigned int)retry_interval);
3106
}
3107
3108
if(not quit_now){
3109
exitcode = EXIT_SUCCESS;
3110
}
3111
3112
goto end;
3113
}
3114
3115
if(quit_now){
3116
goto end;
3117
}
3118
3119
{
3120
AvahiServerConfig config;
3121
/* Do not publish any local Zeroconf records */
3122
avahi_server_config_init(&config);
3123
config.publish_hinfo = 0;
3124
config.publish_addresses = 0;
3125
config.publish_workstation = 0;
3126
config.publish_domain = 0;
3127
3128
/* Allocate a new server */
3129
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
3130
&config, NULL, NULL, &ret);
3131
3132
/* Free the Avahi configuration data */
3133
avahi_server_config_free(&config);
3134
}
3135
3136
/* Check if creating the Avahi server object succeeded */
3137
if(mc.server == NULL){
3138
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
3139
avahi_strerror(ret));
3140
exitcode = EX_UNAVAILABLE;
3141
goto end;
3142
}
3143
3144
if(quit_now){
3145
goto end;
3146
}
3147
3148
/* Create the Avahi service browser */
3149
sb = avahi_s_service_browser_new(mc.server, if_index,
3150
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
3151
NULL, 0, browse_callback,
3152
(void *)&mc);
3153
if(sb == NULL){
3154
fprintf_plus(stderr, "Failed to create service browser: %s\n",
3155
avahi_strerror(avahi_server_errno(mc.server)));
3156
exitcode = EX_UNAVAILABLE;
3157
goto end;
3158
}
3159
3160
if(quit_now){
3161
goto end;
3162
}
3163
3164
/* Run the main loop */
3165
3166
if(debug){
3167
fprintf_plus(stderr, "Starting Avahi loop search\n");
3168
}
3169
3170
ret = avahi_loop_with_timeout(simple_poll,
3171
(int)(retry_interval * 1000), &mc);
3172
if(debug){
3173
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
3174
(ret == 0) ? "successfully" : "with error");
3175
}
3176
1095
3177
end:
1096
1097
if(debug){
1098
fprintf(stderr, "%s exiting\n", argv[0]);
1099
}
1100
1101
/* Cleanup things */
1102
if(sb != NULL)
1103
avahi_s_service_browser_free(sb);
1104
1105
if(mc.server != NULL)
1106
avahi_server_free(mc.server);
1107
1108
if(mc.simple_poll != NULL)
1109
avahi_simple_poll_free(mc.simple_poll);
1110
1111
if(gnutls_initialized){
1112
gnutls_certificate_free_credentials(mc.cred);
1113
gnutls_global_deinit();
1114
gnutls_dh_params_deinit(mc.dh_params);
1115
}
1116
1117
if(gpgme_initialized){
1118
gpgme_release(mc.ctx);
1119
}
1120
1121
/* Removes the temp directory used by GPGME */
1122
if(tempdir_created){
1123
DIR *d;
1124
struct dirent *direntry;
1125
d = opendir(tempdir);
1126
if(d == NULL){
1127
if(errno != ENOENT){
1128
perror("opendir");
1129
}
1130
} else {
1131
while(true){
1132
direntry = readdir(d);
1133
if(direntry == NULL){
1134
break;
1135
}
1136
/* Skip "." and ".." */
1137
if(direntry->d_name[0] == '.'
1138
and (direntry->d_name[1] == '\0'
1139
or (direntry->d_name[1] == '.'
1140
and direntry->d_name[2] == '\0'))){
1141
continue;
1142
}
1143
char *fullname = NULL;
1144
ret = asprintf(&fullname, "%s/%s", tempdir,
1145
direntry->d_name);
1146
if(ret < 0){
1147
perror("asprintf");
1148
continue;
1149
}
1150
ret = remove(fullname);
1151
if(ret == -1){
1152
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1153
strerror(errno));
1154
}
1155
free(fullname);
1156
}
1157
closedir(d);
1158
}
1159
ret = rmdir(tempdir);
1160
if(ret == -1 and errno != ENOENT){
1161
perror("rmdir");
1162
}
1163
}
1164
1165
return exitcode;
3178
3179
if(debug){
3180
if(signal_received){
3181
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
3182
argv[0], signal_received,
3183
strsignal(signal_received));
3184
} else {
3185
fprintf_plus(stderr, "%s exiting\n", argv[0]);
3186
}
3187
}
3188
3189
/* Cleanup things */
3190
free(mc.interfaces);
3191
3192
if(sb != NULL)
3193
avahi_s_service_browser_free(sb);
3194
3195
if(mc.server != NULL)
3196
avahi_server_free(mc.server);
3197
3198
if(simple_poll != NULL)
3199
avahi_simple_poll_free(simple_poll);
3200
3201
if(gnutls_initialized){
3202
gnutls_certificate_free_credentials(mc.cred);
3203
gnutls_dh_params_deinit(mc.dh_params);
3204
}
3205
3206
if(gpgme_initialized){
3207
gpgme_release(mc.ctx);
3208
}
3209
3210
/* Cleans up the circular linked list of Mandos servers the client
3211
has seen */
3212
if(mc.current_server != NULL){
3213
mc.current_server->prev->next = NULL;
3214
while(mc.current_server != NULL){
3215
server *next = mc.current_server->next;
3216
#ifdef __GNUC__
3217
#pragma GCC diagnostic push
3218
#pragma GCC diagnostic ignored "-Wcast-qual"
3219
#endif
3220
free((char *)(mc.current_server->ip));
3221
#ifdef __GNUC__
3222
#pragma GCC diagnostic pop
3223
#endif
3224
free(mc.current_server);
3225
mc.current_server = next;
3226
}
3227
}
3228
3229
/* Re-raise privileges */
3230
{
3231
ret = raise_privileges();
3232
if(ret != 0){
3233
errno = ret;
3234
perror_plus("Failed to raise privileges");
3235
} else {
3236
3237
/* Run network hooks */
3238
run_network_hooks("stop", interfaces_hooks != NULL ?
3239
interfaces_hooks : "", delay);
3240
3241
/* Take down the network interfaces which were brought up */
3242
{
3243
char *interface = NULL;
3244
while((interface = argz_next(interfaces_to_take_down,
3245
interfaces_to_take_down_size,
3246
interface))){
3247
ret = take_down_interface(interface);
3248
if(ret != 0){
3249
errno = ret;
3250
perror_plus("Failed to take down interface");
3251
}
3252
}
3253
if(debug and (interfaces_to_take_down == NULL)){
3254
fprintf_plus(stderr, "No interfaces needed to be taken"
3255
" down\n");
3256
}
3257
}
3258
}
3259
3260
ret = lower_privileges_permanently();
3261
if(ret != 0){
3262
errno = ret;
3263
perror_plus("Failed to lower privileges permanently");
3264
}
3265
}
3266
3267
free(interfaces_to_take_down);
3268
free(interfaces_hooks);
3269
3270
void clean_dir_at(int base, const char * const dirname,
3271
uintmax_t level){
3272
struct dirent **direntries = NULL;
3273
int dret;
3274
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3275
O_RDONLY
3276
| O_NOFOLLOW
3277
| O_DIRECTORY
3278
| O_PATH));
3279
if(dir_fd == -1){
3280
perror_plus("open");
3281
return;
3282
}
3283
int numentries = scandirat(dir_fd, ".", &direntries,
3284
notdotentries, alphasort);
3285
if(numentries >= 0){
3286
for(int i = 0; i < numentries; i++){
3287
if(debug){
3288
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3289
dirname, direntries[i]->d_name);
3290
}
3291
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3292
if(dret == -1){
3293
if(errno == EISDIR){
3294
dret = unlinkat(dir_fd, direntries[i]->d_name,
3295
AT_REMOVEDIR);
3296
}
3297
if((dret == -1) and (errno == ENOTEMPTY)
3298
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3299
== 0) and (level == 0)){
3300
/* Recurse only in this special case */
3301
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3302
dret = 0;
3303
}
3304
if((dret == -1) and (errno != ENOENT)){
3305
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3306
direntries[i]->d_name, strerror(errno));
3307
}
3308
}
3309
free(direntries[i]);
3310
}
3311
3312
/* need to clean even if 0 because man page doesn't specify */
3313
free(direntries);
3314
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3315
if(dret == -1 and errno != ENOENT){
3316
perror_plus("rmdir");
3317
}
3318
} else {
3319
perror_plus("scandirat");
3320
}
3321
close(dir_fd);
3322
}
3323
3324
/* Removes the GPGME temp directory and all files inside */
3325
if(tempdir != NULL){
3326
clean_dir_at(-1, tempdir, 0);
3327
}
3328
3329
if(quit_now){
3330
sigemptyset(&old_sigterm_action.sa_mask);
3331
old_sigterm_action.sa_handler = SIG_DFL;
3332
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3333
&old_sigterm_action,
3334
NULL));
3335
if(ret == -1){
3336
perror_plus("sigaction");
3337
}
3338
do {
3339
ret = raise(signal_received);
3340
} while(ret != 0 and errno == EINTR);
3341
if(ret != 0){
3342
perror_plus("raise");
3343
abort();
3344
}
3345
TEMP_FAILURE_RETRY(pause());
3346
}
3347
3348
return exitcode;
1166
3349
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0