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- Committer: teddy at recompile
- Date: 2020-04-05 21:30:59 UTC
- Revision ID: teddy@recompile.se-20200405213059-fb2a61ckqynrmatk
Fix file descriptor leak in mandos-client
When the local network has Mandos servers announcing themselves using
real, globally reachable, IPv6 addresses (i.e. not link-local
addresses), but there is no router on the local network providing IPv6
RA (Router Advertisement) packets, the client cannot reach the server
by normal means, since the client only has a link-local IPv6 address,
and has no usable route to reach the server's global IPv6 address.
(This is not a common situation, and usually only happens when the
router itself reboots and runs a Mandos client, since it cannot then
give RA packets to itself.) The client code has a solution for
this, which consists of adding a temporary local route to reach the
address of the server during communication, and removing this
temporary route afterwards.
This solution with a temporary route works, but has a file descriptor
leak; it leaks one file descriptor for each addition and for each
removal of a route. If one server requiring an added route is present
on the network, but no servers gives a password, making the client
retry after the default ten seconds, and we furthermore assume a
default 1024 open files limit, the client runs out of file descriptors
after about 90 minutes, after which time the client process will be
useless and fail to retrieve any passwords, necessitating manual
password entry via the keyboard.
Fix this by eliminating the file descriptor leak in the client.
* plugins.d/mandos-client.c (add_delete_local_route): Do
close(devnull) also in parent process, also if fork() fails, and on
any failure in child process.
When the local network has Mandos servers announcing themselves using
real, globally reachable, IPv6 addresses (i.e. not link-local
addresses), but there is no router on the local network providing IPv6
RA (Router Advertisement) packets, the client cannot reach the server
by normal means, since the client only has a link-local IPv6 address,
and has no usable route to reach the server's global IPv6 address.
(This is not a common situation, and usually only happens when the
router itself reboots and runs a Mandos client, since it cannot then
give RA packets to itself.) The client code has a solution for
this, which consists of adding a temporary local route to reach the
address of the server during communication, and removing this
temporary route afterwards.
This solution with a temporary route works, but has a file descriptor
leak; it leaks one file descriptor for each addition and for each
removal of a route. If one server requiring an added route is present
on the network, but no servers gives a password, making the client
retry after the default ten seconds, and we furthermore assume a
default 1024 open files limit, the client runs out of file descriptors
after about 90 minutes, after which time the client process will be
useless and fail to retrieve any passwords, necessitating manual
password entry via the keyboard.
Fix this by eliminating the file descriptor leak in the client.
* plugins.d/mandos-client.c (add_delete_local_route): Do
close(devnull) also in parent process, also if fork() fails, and on
any failure in child process.
- files added:
- bugs.xml
- debian/source
- debian/tests
- debian/upstream
- dracut-module
- 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 © 2008-2010 Teddy Hogeborn
13
* Copyright © 2008-2010 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() */
33
34
#ifndef _LARGEFILE_SOURCE
34
35
#define _LARGEFILE_SOURCE
35
#endif
36
#endif /* not _LARGEFILE_SOURCE */
36
37
#ifndef _FILE_OFFSET_BITS
37
38
#define _FILE_OFFSET_BITS 64
38
#endif
39
#endif /* not _FILE_OFFSET_BITS */
39
40
40
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
42
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
44
stdout, ferror() */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
46
#include <stddef.h> /* NULL, size_t, ssize_t */
46
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
48
strtof(), abort() */
48
49
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
52
*/
51
53
#include <sys/ioctl.h> /* ioctl */
52
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
55
sockaddr_in6, PF_INET6,
54
56
SOCK_STREAM, uid_t, gid_t, open(),
55
57
opendir(), DIR */
56
#include <sys/stat.h> /* open() */
58
#include <sys/stat.h> /* open(), S_ISREG */
57
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
61
getnameinfo() */
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
64
*/
62
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
66
strtoimax() */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
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 */
66
73
#include <time.h> /* nanosleep(), time(), sleep() */
67
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
75
SIOCSIFFLAGS, if_indextoname(),
72
79
*/
73
80
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
81
getuid(), getgid(), seteuid(),
75
setgid(), pause() */
76
#include <arpa/inet.h> /* inet_pton(), htons */
82
setgid(), pause(), _exit(),
83
unlinkat() */
84
#include <arpa/inet.h> /* inet_pton(), htons() */
77
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#include <iso646.h> /* not, or, and */
78
86
#include <argp.h> /* struct argp_option, error_t, struct
79
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argp_state, struct argp,
84
92
raise() */
85
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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
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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() */
87
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88
105
#ifdef __linux__
89
106
#include <sys/klog.h> /* klogctl() */
106
123
gnutls_*
107
124
init_gnutls_session(),
108
125
GNUTLS_* */
126
#if GNUTLS_VERSION_NUMBER < 0x030600
109
127
#include <gnutls/openpgp.h>
110
/* gnutls_certificate_set_openpgp_key_file(),
111
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
112
135
113
136
/* GPGME */
114
137
#include <gpgme.h> /* All GPGME types, constants and
122
145
#define PATHDIR "/conf/conf.d/mandos"
123
146
#define SECKEY "seckey.txt"
124
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"
125
151
126
152
bool debug = false;
127
153
static const char mandos_protocol_version[] = "1";
128
154
const char *argp_program_version = "mandos-client " VERSION;
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
155
const char *argp_program_bug_address = "<mandos@recompile.se>";
130
156
static const char sys_class_net[] = "/sys/class/net";
131
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;
132
173
133
174
/* Used for passing in values through the Avahi callback functions */
134
175
typedef struct {
135
AvahiSimplePoll *simple_poll;
136
176
AvahiServer *server;
137
177
gnutls_certificate_credentials_t cred;
138
178
unsigned int dh_bits;
139
179
gnutls_dh_params_t dh_params;
140
180
const char *priority;
141
181
gpgme_ctx_t ctx;
182
server *current_server;
183
char *interfaces;
184
size_t interfaces_size;
142
185
} mandos_context;
143
186
144
/* global context so signal handler can reach it*/
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
187
/* global so signal handler can reach it*/
188
AvahiSimplePoll *simple_poll;
148
189
149
190
sig_atomic_t quit_now = 0;
150
191
int signal_received = 0;
151
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
152
212
/*
153
213
* Make additional room in "buffer" for at least BUFFER_SIZE more
154
214
* bytes. "buffer_capacity" is how much is currently allocated,
155
215
* "buffer_length" is how much is already used.
156
216
*/
217
__attribute__((nonnull, warn_unused_result))
157
218
size_t incbuffer(char **buffer, size_t buffer_length,
158
size_t buffer_capacity){
219
size_t buffer_capacity){
159
220
if(buffer_length + BUFFER_SIZE > buffer_capacity){
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
161
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;
162
227
return 0;
163
228
}
229
*buffer = new_buf;
164
230
buffer_capacity += BUFFER_SIZE;
165
231
}
166
232
return buffer_capacity;
167
233
}
168
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
169
335
/*
170
336
* Initialize GPGME.
171
337
*/
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
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){
174
343
gpgme_error_t rc;
175
344
gpgme_engine_info_t engine_info;
176
345
177
178
346
/*
179
347
* Helper function to insert pub and seckey to the engine keyring.
180
348
*/
181
bool import_key(const char *filename){
349
bool import_key(const char * const filename){
182
350
int ret;
183
351
int fd;
184
352
gpgme_data_t pgp_data;
185
353
186
354
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
187
355
if(fd == -1){
188
perror("open");
356
perror_plus("open");
189
357
return false;
190
358
}
191
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
192
410
rc = gpgme_data_new_from_fd(&pgp_data, fd);
193
411
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
195
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));
196
414
return false;
197
415
}
198
416
199
rc = gpgme_op_import(mc.ctx, pgp_data);
417
rc = gpgme_op_import(mc->ctx, pgp_data);
200
418
if(rc != GPG_ERR_NO_ERROR){
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
gpgme_strsource(rc), gpgme_strerror(rc));
419
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
420
gpgme_strsource(rc), gpgme_strerror(rc));
203
421
return false;
204
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
}
205
498
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
499
ret = close(fd);
207
500
if(ret == -1){
208
perror("close");
501
perror_plus("close");
209
502
}
210
503
gpgme_data_release(pgp_data);
211
504
return true;
212
505
}
213
506
214
507
if(debug){
215
fprintf(stderr, "Initializing GPGME\n");
508
fprintf_plus(stderr, "Initializing GPGME\n");
216
509
}
217
510
218
511
/* Init GPGME */
219
512
gpgme_check_version(NULL);
220
513
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
221
514
if(rc != GPG_ERR_NO_ERROR){
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
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));
224
517
return false;
225
518
}
226
519
227
/* Set GPGME home directory for the OpenPGP engine only */
520
/* Set GPGME home directory for the OpenPGP engine only */
228
521
rc = gpgme_get_engine_info(&engine_info);
229
522
if(rc != GPG_ERR_NO_ERROR){
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
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));
232
525
return false;
233
526
}
234
527
while(engine_info != NULL){
240
533
engine_info = engine_info->next;
241
534
}
242
535
if(engine_info == NULL){
243
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);
244
538
return false;
245
539
}
246
540
247
541
/* Create new GPGME "context" */
248
rc = gpgme_new(&(mc.ctx));
542
rc = gpgme_new(&(mc->ctx));
249
543
if(rc != GPG_ERR_NO_ERROR){
250
fprintf(stderr, "bad gpgme_new: %s: %s\n",
251
gpgme_strsource(rc), gpgme_strerror(rc));
544
fprintf_plus(stderr, "bad gpgme_new: %s: %s\n",
545
gpgme_strsource(rc), gpgme_strerror(rc));
252
546
return false;
253
547
}
254
548
263
557
* Decrypt OpenPGP data.
264
558
* Returns -1 on error
265
559
*/
560
__attribute__((nonnull, warn_unused_result))
266
561
static ssize_t pgp_packet_decrypt(const char *cryptotext,
267
562
size_t crypto_size,
268
char **plaintext){
563
char **plaintext,
564
mandos_context *mc){
269
565
gpgme_data_t dh_crypto, dh_plain;
270
566
gpgme_error_t rc;
271
567
ssize_t ret;
273
569
ssize_t plaintext_length = 0;
274
570
275
571
if(debug){
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
572
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
277
573
}
278
574
279
575
/* Create new GPGME data buffer from memory cryptotext */
280
576
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
281
577
0);
282
578
if(rc != GPG_ERR_NO_ERROR){
283
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
284
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));
285
581
return -1;
286
582
}
287
583
288
584
/* Create new empty GPGME data buffer for the plaintext */
289
585
rc = gpgme_data_new(&dh_plain);
290
586
if(rc != GPG_ERR_NO_ERROR){
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
587
fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",
588
gpgme_strsource(rc), gpgme_strerror(rc));
293
589
gpgme_data_release(dh_crypto);
294
590
return -1;
295
591
}
296
592
297
593
/* Decrypt data from the cryptotext data buffer to the plaintext
298
594
data buffer */
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
595
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
300
596
if(rc != GPG_ERR_NO_ERROR){
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
597
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
598
gpgme_strsource(rc), gpgme_strerror(rc));
303
599
plaintext_length = -1;
304
600
if(debug){
305
601
gpgme_decrypt_result_t result;
306
result = gpgme_op_decrypt_result(mc.ctx);
602
result = gpgme_op_decrypt_result(mc->ctx);
307
603
if(result == NULL){
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
604
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
309
605
} else {
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
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");
314
612
if(result->file_name != NULL){
315
fprintf(stderr, "File name: %s\n", result->file_name);
613
fprintf_plus(stderr, "File name: %s\n", result->file_name);
316
614
}
317
gpgme_recipient_t recipient;
318
recipient = result->recipients;
319
while(recipient != NULL){
320
fprintf(stderr, "Public key algorithm: %s\n",
321
gpgme_pubkey_algo_name(recipient->pubkey_algo));
322
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
323
fprintf(stderr, "Secret key available: %s\n",
324
recipient->status == GPG_ERR_NO_SECKEY
325
? "No" : "Yes");
326
recipient = recipient->next;
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");
327
623
}
328
624
}
329
625
}
331
627
}
332
628
333
629
if(debug){
334
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
630
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
335
631
}
336
632
337
633
/* Seek back to the beginning of the GPGME plaintext data buffer */
338
634
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
339
perror("gpgme_data_seek");
635
perror_plus("gpgme_data_seek");
340
636
plaintext_length = -1;
341
637
goto decrypt_end;
342
638
}
344
640
*plaintext = NULL;
345
641
while(true){
346
642
plaintext_capacity = incbuffer(plaintext,
347
(size_t)plaintext_length,
348
plaintext_capacity);
643
(size_t)plaintext_length,
644
plaintext_capacity);
349
645
if(plaintext_capacity == 0){
350
perror("incbuffer");
351
plaintext_length = -1;
352
goto decrypt_end;
646
perror_plus("incbuffer");
647
plaintext_length = -1;
648
goto decrypt_end;
353
649
}
354
650
355
651
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
360
656
break;
361
657
}
362
658
if(ret < 0){
363
perror("gpgme_data_read");
659
perror_plus("gpgme_data_read");
364
660
plaintext_length = -1;
365
661
goto decrypt_end;
366
662
}
368
664
}
369
665
370
666
if(debug){
371
fprintf(stderr, "Decrypted password is: ");
667
fprintf_plus(stderr, "Decrypted password is: ");
372
668
for(ssize_t i = 0; i < plaintext_length; i++){
373
669
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
374
670
}
385
681
return plaintext_length;
386
682
}
387
683
388
static const char * safer_gnutls_strerror(int value){
389
const char *ret = gnutls_strerror(value); /* Spurious warning from
390
-Wunreachable-code */
391
if(ret == NULL)
392
ret = "(unknown)";
393
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);
394
695
}
395
696
396
697
/* GnuTLS log function callback */
698
__attribute__((nonnull))
397
699
static void debuggnutls(__attribute__((unused)) int level,
398
700
const char* string){
399
fprintf(stderr, "GnuTLS: %s", string);
701
fprintf_plus(stderr, "GnuTLS: %s", string);
400
702
}
401
703
704
__attribute__((nonnull(1, 2, 4), warn_unused_result))
402
705
static int init_gnutls_global(const char *pubkeyfilename,
403
const char *seckeyfilename){
706
const char *seckeyfilename,
707
const char *dhparamsfilename,
708
mandos_context *mc){
404
709
int ret;
405
710
406
711
if(debug){
407
fprintf(stderr, "Initializing GnuTLS\n");
408
}
409
410
ret = gnutls_global_init();
411
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS global_init: %s\n",
413
safer_gnutls_strerror(ret));
414
return -1;
712
fprintf_plus(stderr, "Initializing GnuTLS\n");
415
713
}
416
714
417
715
if(debug){
423
721
}
424
722
425
723
/* OpenPGP credentials */
426
gnutls_certificate_allocate_credentials(&mc.cred);
724
ret = gnutls_certificate_allocate_credentials(&mc->cred);
427
725
if(ret != GNUTLS_E_SUCCESS){
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
429
from
430
-Wunreachable-code
431
*/
432
safer_gnutls_strerror(ret));
433
gnutls_global_deinit();
726
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
727
safer_gnutls_strerror(ret));
434
728
return -1;
435
729
}
436
730
437
731
if(debug){
438
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
439
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
440
seckeyfilename);
732
fprintf_plus(stderr, "Attempting to use public key %s and"
733
" private key %s as GnuTLS credentials\n",
734
pubkeyfilename,
735
seckeyfilename);
441
736
}
442
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
443
751
ret = gnutls_certificate_set_openpgp_key_file
444
(mc.cred, pubkeyfilename, seckeyfilename,
752
(mc->cred, pubkeyfilename, seckeyfilename,
445
753
GNUTLS_OPENPGP_FMT_BASE64);
754
#else
755
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
756
#endif
446
757
if(ret != GNUTLS_E_SUCCESS){
447
fprintf(stderr,
448
"Error[%d] while reading the OpenPGP key pair ('%s',"
449
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
450
fprintf(stderr, "The GnuTLS error is: %s\n",
451
safer_gnutls_strerror(ret));
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));
452
763
goto globalfail;
453
764
}
454
765
455
766
/* GnuTLS server initialization */
456
ret = gnutls_dh_params_init(&mc.dh_params);
457
if(ret != GNUTLS_E_SUCCESS){
458
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
459
" %s\n", safer_gnutls_strerror(ret));
460
goto globalfail;
461
}
462
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
463
if(ret != GNUTLS_E_SUCCESS){
464
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
465
safer_gnutls_strerror(ret));
466
goto globalfail;
467
}
468
469
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
767
ret = gnutls_dh_params_init(&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
}
470
956
471
957
return 0;
472
958
473
959
globalfail:
474
960
475
gnutls_certificate_free_credentials(mc.cred);
476
gnutls_global_deinit();
477
gnutls_dh_params_deinit(mc.dh_params);
961
gnutls_certificate_free_credentials(mc->cred);
962
gnutls_dh_params_deinit(mc->dh_params);
478
963
return -1;
479
964
}
480
965
481
static int init_gnutls_session(gnutls_session_t *session){
966
__attribute__((nonnull, warn_unused_result))
967
static int init_gnutls_session(gnutls_session_t *session,
968
mandos_context *mc){
482
969
int ret;
483
970
/* GnuTLS session creation */
484
971
do {
485
ret = gnutls_init(session, GNUTLS_SERVER);
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
));
486
980
if(quit_now){
487
981
return -1;
488
982
}
489
983
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
490
984
if(ret != GNUTLS_E_SUCCESS){
491
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
492
safer_gnutls_strerror(ret));
985
fprintf_plus(stderr,
986
"Error in GnuTLS session initialization: %s\n",
987
safer_gnutls_strerror(ret));
493
988
}
494
989
495
990
{
496
991
const char *err;
497
992
do {
498
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
993
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
499
994
if(quit_now){
500
995
gnutls_deinit(*session);
501
996
return -1;
502
997
}
503
998
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
504
999
if(ret != GNUTLS_E_SUCCESS){
505
fprintf(stderr, "Syntax error at: %s\n", err);
506
fprintf(stderr, "GnuTLS error: %s\n",
507
safer_gnutls_strerror(ret));
1000
fprintf_plus(stderr, "Syntax error at: %s\n", err);
1001
fprintf_plus(stderr, "GnuTLS error: %s\n",
1002
safer_gnutls_strerror(ret));
508
1003
gnutls_deinit(*session);
509
1004
return -1;
510
1005
}
512
1007
513
1008
do {
514
1009
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
515
mc.cred);
1010
mc->cred);
516
1011
if(quit_now){
517
1012
gnutls_deinit(*session);
518
1013
return -1;
519
1014
}
520
1015
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
521
1016
if(ret != GNUTLS_E_SUCCESS){
522
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
523
safer_gnutls_strerror(ret));
1017
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
1018
safer_gnutls_strerror(ret));
524
1019
gnutls_deinit(*session);
525
1020
return -1;
526
1021
}
528
1023
/* ignore client certificate if any. */
529
1024
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
530
1025
531
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
532
533
1026
return 0;
534
1027
}
535
1028
537
1030
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
538
1031
__attribute__((unused)) const char *txt){}
539
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
close(devnull);
1078
_exit(EX_NOPERM);
1079
}
1080
/* Reset supplementary groups */
1081
errno = 0;
1082
ret = setgroups(0, NULL);
1083
if(ret == -1){
1084
perror_plus("setgroups");
1085
close(devnull);
1086
_exit(EX_NOPERM);
1087
}
1088
}
1089
ret = dup2(devnull, STDIN_FILENO);
1090
if(ret == -1){
1091
perror_plus("dup2(devnull, STDIN_FILENO)");
1092
close(devnull);
1093
_exit(EX_OSERR);
1094
}
1095
ret = close(devnull);
1096
if(ret == -1){
1097
perror_plus("close");
1098
}
1099
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1100
if(ret == -1){
1101
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1102
_exit(EX_OSERR);
1103
}
1104
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1105
O_RDONLY
1106
| O_DIRECTORY
1107
| O_PATH
1108
| O_CLOEXEC));
1109
if(helperdir_fd == -1){
1110
perror_plus("open");
1111
_exit(EX_UNAVAILABLE);
1112
}
1113
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1114
helper, O_RDONLY));
1115
if(helper_fd == -1){
1116
perror_plus("openat");
1117
close(helperdir_fd);
1118
_exit(EX_UNAVAILABLE);
1119
}
1120
close(helperdir_fd);
1121
#ifdef __GNUC__
1122
#pragma GCC diagnostic push
1123
#pragma GCC diagnostic ignored "-Wcast-qual"
1124
#endif
1125
if(fexecve(helper_fd, (char *const [])
1126
{ helper, add ? add_arg : delete_arg, (char *)address,
1127
interface, debug ? debug_flag : NULL, NULL },
1128
environ) == -1){
1129
#ifdef __GNUC__
1130
#pragma GCC diagnostic pop
1131
#endif
1132
perror_plus("fexecve");
1133
_exit(EXIT_FAILURE);
1134
}
1135
}
1136
if(pid == -1){
1137
perror_plus("fork");
1138
close(devnull);
1139
return false;
1140
}
1141
ret = close(devnull);
1142
if(ret == -1){
1143
perror_plus("close");
1144
}
1145
int status;
1146
pid_t pret = -1;
1147
errno = 0;
1148
do {
1149
pret = waitpid(pid, &status, 0);
1150
if(pret == -1 and errno == EINTR and quit_now){
1151
int errno_raising = 0;
1152
if((errno = raise_privileges()) != 0){
1153
errno_raising = errno;
1154
perror_plus("Failed to raise privileges in order to"
1155
" kill helper program");
1156
}
1157
if(kill(pid, SIGTERM) == -1){
1158
perror_plus("kill");
1159
}
1160
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1161
perror_plus("Failed to lower privileges after killing"
1162
" helper program");
1163
}
1164
return false;
1165
}
1166
} while(pret == -1 and errno == EINTR);
1167
if(pret == -1){
1168
perror_plus("waitpid");
1169
return false;
1170
}
1171
if(WIFEXITED(status)){
1172
if(WEXITSTATUS(status) != 0){
1173
fprintf_plus(stderr, "Error: iprouteadddel exited"
1174
" with status %d\n", WEXITSTATUS(status));
1175
return false;
1176
}
1177
return true;
1178
}
1179
if(WIFSIGNALED(status)){
1180
fprintf_plus(stderr, "Error: iprouteadddel died by"
1181
" signal %d\n", WTERMSIG(status));
1182
return false;
1183
}
1184
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1185
return false;
1186
}
1187
1188
__attribute__((nonnull, warn_unused_result))
1189
static bool add_local_route(const char *address,
1190
AvahiIfIndex if_index){
1191
if(debug){
1192
fprintf_plus(stderr, "Adding route to %s\n", address);
1193
}
1194
return add_delete_local_route(true, address, if_index);
1195
}
1196
1197
__attribute__((nonnull, warn_unused_result))
1198
static bool delete_local_route(const char *address,
1199
AvahiIfIndex if_index){
1200
if(debug){
1201
fprintf_plus(stderr, "Removing route to %s\n", address);
1202
}
1203
return add_delete_local_route(false, address, if_index);
1204
}
1205
540
1206
/* Called when a Mandos server is found */
541
static int start_mandos_communication(const char *ip, uint16_t port,
1207
__attribute__((nonnull, warn_unused_result))
1208
static int start_mandos_communication(const char *ip, in_port_t port,
542
1209
AvahiIfIndex if_index,
543
int af){
1210
int af, mandos_context *mc){
544
1211
int ret, tcp_sd = -1;
545
1212
ssize_t sret;
546
union {
547
struct sockaddr_in in;
548
struct sockaddr_in6 in6;
549
} to;
1213
struct sockaddr_storage to;
550
1214
char *buffer = NULL;
551
1215
char *decrypted_buffer = NULL;
552
1216
size_t buffer_length = 0;
555
1219
int retval = -1;
556
1220
gnutls_session_t session;
557
1221
int pf; /* Protocol family */
1222
bool route_added = false;
558
1223
559
1224
errno = 0;
560
1225
571
1236
pf = PF_INET;
572
1237
break;
573
1238
default:
574
fprintf(stderr, "Bad address family: %d\n", af);
1239
fprintf_plus(stderr, "Bad address family: %d\n", af);
575
1240
errno = EINVAL;
576
1241
return -1;
577
1242
}
578
1243
579
ret = init_gnutls_session(&session);
1244
/* If the interface is specified and we have a list of interfaces */
1245
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1246
/* Check if the interface is one of the interfaces we are using */
1247
bool match = false;
1248
{
1249
char *interface = NULL;
1250
while((interface = argz_next(mc->interfaces,
1251
mc->interfaces_size,
1252
interface))){
1253
if(if_nametoindex(interface) == (unsigned int)if_index){
1254
match = true;
1255
break;
1256
}
1257
}
1258
}
1259
if(not match){
1260
/* This interface does not match any in the list, so we don't
1261
connect to the server */
1262
if(debug){
1263
char interface[IF_NAMESIZE];
1264
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1265
perror_plus("if_indextoname");
1266
} else {
1267
fprintf_plus(stderr, "Skipping server on non-used interface"
1268
" \"%s\"\n",
1269
if_indextoname((unsigned int)if_index,
1270
interface));
1271
}
1272
}
1273
return -1;
1274
}
1275
}
1276
1277
ret = init_gnutls_session(&session, mc);
580
1278
if(ret != 0){
581
1279
return -1;
582
1280
}
583
1281
584
1282
if(debug){
585
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
586
"\n", ip, port);
1283
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1284
PRIuMAX "\n", ip, (uintmax_t)port);
587
1285
}
588
1286
589
tcp_sd = socket(pf, SOCK_STREAM, 0);
1287
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
590
1288
if(tcp_sd < 0){
591
1289
int e = errno;
592
perror("socket");
1290
perror_plus("socket");
593
1291
errno = e;
594
1292
goto mandos_end;
595
1293
}
599
1297
goto mandos_end;
600
1298
}
601
1299
602
memset(&to, 0, sizeof(to));
603
1300
if(af == AF_INET6){
604
to.in6.sin6_family = (sa_family_t)af;
605
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1301
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1302
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1303
ret = inet_pton(af, ip, &to6->sin6_addr);
606
1304
} else { /* IPv4 */
607
to.in.sin_family = (sa_family_t)af;
608
ret = inet_pton(af, ip, &to.in.sin_addr);
1305
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1306
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1307
ret = inet_pton(af, ip, &to4->sin_addr);
609
1308
}
610
1309
if(ret < 0 ){
611
1310
int e = errno;
612
perror("inet_pton");
1311
perror_plus("inet_pton");
613
1312
errno = e;
614
1313
goto mandos_end;
615
1314
}
616
1315
if(ret == 0){
617
1316
int e = errno;
618
fprintf(stderr, "Bad address: %s\n", ip);
1317
fprintf_plus(stderr, "Bad address: %s\n", ip);
619
1318
errno = e;
620
1319
goto mandos_end;
621
1320
}
622
1321
if(af == AF_INET6){
623
to.in6.sin6_port = htons(port); /* Spurious warnings from
624
-Wconversion and
625
-Wunreachable-code */
626
627
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
628
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
629
-Wunreachable-code*/
1322
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1323
if(IN6_IS_ADDR_LINKLOCAL
1324
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
630
1325
if(if_index == AVAHI_IF_UNSPEC){
631
fprintf(stderr, "An IPv6 link-local address is incomplete"
632
" without a network interface\n");
1326
fprintf_plus(stderr, "An IPv6 link-local address is"
1327
" incomplete without a network interface\n");
633
1328
errno = EINVAL;
634
1329
goto mandos_end;
635
1330
}
636
1331
/* Set the network interface number as scope */
637
to.in6.sin6_scope_id = (uint32_t)if_index;
1332
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
638
1333
}
639
1334
} else {
640
to.in.sin_port = htons(port); /* Spurious warnings from
641
-Wconversion and
642
-Wunreachable-code */
1335
((struct sockaddr_in *)&to)->sin_port = htons(port);
643
1336
}
644
1337
645
1338
if(quit_now){
651
1344
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
652
1345
char interface[IF_NAMESIZE];
653
1346
if(if_indextoname((unsigned int)if_index, interface) == NULL){
654
perror("if_indextoname");
1347
perror_plus("if_indextoname");
655
1348
} else {
656
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
657
ip, interface, port);
1349
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1350
"\n", ip, interface, (uintmax_t)port);
658
1351
}
659
1352
} else {
660
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
661
port);
1353
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1354
ip, (uintmax_t)port);
662
1355
}
663
1356
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
664
1357
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
665
const char *pcret;
666
if(af == AF_INET6){
667
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
668
sizeof(addrstr));
669
} else {
670
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
671
sizeof(addrstr));
672
}
673
if(pcret == NULL){
674
perror("inet_ntop");
675
} else {
676
if(strcmp(addrstr, ip) != 0){
677
fprintf(stderr, "Canonical address form: %s\n", addrstr);
678
}
679
}
680
}
681
682
if(quit_now){
683
errno = EINTR;
684
goto mandos_end;
685
}
686
687
if(af == AF_INET6){
688
ret = connect(tcp_sd, &to.in6, sizeof(to));
689
} else {
690
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
691
}
692
if(ret < 0){
693
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
694
int e = errno;
695
perror("connect");
696
errno = e;
697
}
698
goto mandos_end;
699
}
700
701
if(quit_now){
702
errno = EINTR;
703
goto mandos_end;
1358
if(af == AF_INET6){
1359
ret = getnameinfo((struct sockaddr *)&to,
1360
sizeof(struct sockaddr_in6),
1361
addrstr, sizeof(addrstr), NULL, 0,
1362
NI_NUMERICHOST);
1363
} else {
1364
ret = getnameinfo((struct sockaddr *)&to,
1365
sizeof(struct sockaddr_in),
1366
addrstr, sizeof(addrstr), NULL, 0,
1367
NI_NUMERICHOST);
1368
}
1369
if(ret == EAI_SYSTEM){
1370
perror_plus("getnameinfo");
1371
} else if(ret != 0) {
1372
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1373
} else if(strcmp(addrstr, ip) != 0){
1374
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1375
}
1376
}
1377
1378
if(quit_now){
1379
errno = EINTR;
1380
goto mandos_end;
1381
}
1382
1383
while(true){
1384
if(af == AF_INET6){
1385
ret = connect(tcp_sd, (struct sockaddr *)&to,
1386
sizeof(struct sockaddr_in6));
1387
} else {
1388
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1389
sizeof(struct sockaddr_in));
1390
}
1391
if(ret < 0){
1392
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1393
and if_index != AVAHI_IF_UNSPEC
1394
and connect_to == NULL
1395
and not route_added and
1396
((af == AF_INET6 and not
1397
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1398
&to)->sin6_addr)))
1399
or (af == AF_INET and
1400
/* Not a a IPv4LL address */
1401
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1402
& 0xFFFF0000L) != 0xA9FE0000L))){
1403
/* Work around Avahi bug - Avahi does not announce link-local
1404
addresses if it has a global address, so local hosts with
1405
*only* a link-local address (e.g. Mandos clients) cannot
1406
connect to a Mandos server announced by Avahi on a server
1407
host with a global address. Work around this by retrying
1408
with an explicit route added with the server's address.
1409
1410
Avahi bug reference:
1411
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1412
https://bugs.debian.org/587961
1413
*/
1414
if(debug){
1415
fprintf_plus(stderr, "Mandos server unreachable, trying"
1416
" direct route\n");
1417
}
1418
int e = errno;
1419
route_added = add_local_route(ip, if_index);
1420
if(route_added){
1421
continue;
1422
}
1423
errno = e;
1424
}
1425
if(errno != ECONNREFUSED or debug){
1426
int e = errno;
1427
perror_plus("connect");
1428
errno = e;
1429
}
1430
goto mandos_end;
1431
}
1432
1433
if(quit_now){
1434
errno = EINTR;
1435
goto mandos_end;
1436
}
1437
break;
704
1438
}
705
1439
706
1440
const char *out = mandos_protocol_version;
708
1442
while(true){
709
1443
size_t out_size = strlen(out);
710
1444
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
711
out_size - written));
1445
out_size - written));
712
1446
if(ret == -1){
713
1447
int e = errno;
714
perror("write");
1448
perror_plus("write");
715
1449
errno = e;
716
1450
goto mandos_end;
717
1451
}
734
1468
}
735
1469
736
1470
if(debug){
737
fprintf(stderr, "Establishing TLS session with %s\n", ip);
1471
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
738
1472
}
739
1473
740
1474
if(quit_now){
742
1476
goto mandos_end;
743
1477
}
744
1478
745
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
1479
/* This casting via intptr_t is to eliminate warning about casting
1480
an int to a pointer type. This is exactly how the GnuTLS Guile
1481
function "set-session-transport-fd!" does it. */
1482
gnutls_transport_set_ptr(session,
1483
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
746
1484
747
1485
if(quit_now){
748
1486
errno = EINTR;
759
1497
760
1498
if(ret != GNUTLS_E_SUCCESS){
761
1499
if(debug){
762
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1500
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
763
1501
gnutls_perror(ret);
764
1502
}
765
1503
errno = EPROTO;
769
1507
/* Read OpenPGP packet that contains the wanted password */
770
1508
771
1509
if(debug){
772
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
773
ip);
1510
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1511
" %s\n", ip);
774
1512
}
775
1513
776
1514
while(true){
781
1519
}
782
1520
783
1521
buffer_capacity = incbuffer(&buffer, buffer_length,
784
buffer_capacity);
1522
buffer_capacity);
785
1523
if(buffer_capacity == 0){
786
1524
int e = errno;
787
perror("incbuffer");
1525
perror_plus("incbuffer");
788
1526
errno = e;
789
1527
goto mandos_end;
790
1528
}
814
1552
}
815
1553
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
816
1554
if(ret < 0){
817
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1555
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1556
"***\n");
818
1557
gnutls_perror(ret);
819
1558
errno = EPROTO;
820
1559
goto mandos_end;
821
1560
}
822
1561
break;
823
1562
default:
824
fprintf(stderr, "Unknown error while reading data from"
825
" encrypted session with Mandos server\n");
1563
fprintf_plus(stderr, "Unknown error while reading data from"
1564
" encrypted session with Mandos server\n");
826
1565
gnutls_bye(session, GNUTLS_SHUT_RDWR);
827
1566
errno = EIO;
828
1567
goto mandos_end;
833
1572
}
834
1573
835
1574
if(debug){
836
fprintf(stderr, "Closing TLS session\n");
1575
fprintf_plus(stderr, "Closing TLS session\n");
837
1576
}
838
1577
839
1578
if(quit_now){
851
1590
852
1591
if(buffer_length > 0){
853
1592
ssize_t decrypted_buffer_size;
854
decrypted_buffer_size = pgp_packet_decrypt(buffer,
855
buffer_length,
856
&decrypted_buffer);
1593
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1594
&decrypted_buffer, mc);
857
1595
if(decrypted_buffer_size >= 0){
858
1596
1597
clearerr(stdout);
859
1598
written = 0;
860
1599
while(written < (size_t) decrypted_buffer_size){
861
1600
if(quit_now){
869
1608
if(ret == 0 and ferror(stdout)){
870
1609
int e = errno;
871
1610
if(debug){
872
fprintf(stderr, "Error writing encrypted data: %s\n",
873
strerror(errno));
1611
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1612
strerror(errno));
874
1613
}
875
1614
errno = e;
876
1615
goto mandos_end;
877
1616
}
878
1617
written += (size_t)ret;
879
1618
}
1619
ret = fflush(stdout);
1620
if(ret != 0){
1621
int e = errno;
1622
if(debug){
1623
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1624
strerror(errno));
1625
}
1626
errno = e;
1627
goto mandos_end;
1628
}
880
1629
retval = 0;
881
1630
}
882
1631
}
885
1634
886
1635
mandos_end:
887
1636
{
1637
if(route_added){
1638
if(not delete_local_route(ip, if_index)){
1639
fprintf_plus(stderr, "Failed to delete local route to %s on"
1640
" interface %d", ip, if_index);
1641
}
1642
}
888
1643
int e = errno;
889
1644
free(decrypted_buffer);
890
1645
free(buffer);
891
1646
if(tcp_sd >= 0){
892
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1647
ret = close(tcp_sd);
893
1648
}
894
1649
if(ret == -1){
895
1650
if(e == 0){
896
1651
e = errno;
897
1652
}
898
perror("close");
1653
perror_plus("close");
899
1654
}
900
1655
gnutls_deinit(session);
1656
errno = e;
901
1657
if(quit_now){
902
e = EINTR;
1658
errno = EINTR;
903
1659
retval = -1;
904
1660
}
905
errno = e;
906
1661
}
907
1662
return retval;
908
1663
}
920
1675
AVAHI_GCC_UNUSED AvahiStringList *txt,
921
1676
AVAHI_GCC_UNUSED AvahiLookupResultFlags
922
1677
flags,
923
AVAHI_GCC_UNUSED void* userdata){
924
assert(r);
1678
void *mc){
1679
if(r == NULL){
1680
return;
1681
}
925
1682
926
1683
/* Called whenever a service has been resolved successfully or
927
1684
timed out */
928
1685
929
1686
if(quit_now){
1687
avahi_s_service_resolver_free(r);
930
1688
return;
931
1689
}
932
1690
933
1691
switch(event){
934
1692
default:
935
1693
case AVAHI_RESOLVER_FAILURE:
936
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
937
" of type '%s' in domain '%s': %s\n", name, type, domain,
938
avahi_strerror(avahi_server_errno(mc.server)));
1694
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1695
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1696
domain,
1697
avahi_strerror(avahi_server_errno
1698
(((mandos_context*)mc)->server)));
939
1699
break;
940
1700
941
1701
case AVAHI_RESOLVER_FOUND:
943
1703
char ip[AVAHI_ADDRESS_STR_MAX];
944
1704
avahi_address_snprint(ip, sizeof(ip), address);
945
1705
if(debug){
946
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
947
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
948
ip, (intmax_t)interface, port);
1706
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1707
PRIdMAX ") on port %" PRIu16 "\n", name,
1708
host_name, ip, (intmax_t)interface, port);
949
1709
}
950
int ret = start_mandos_communication(ip, port, interface,
951
avahi_proto_to_af(proto));
1710
int ret = start_mandos_communication(ip, (in_port_t)port,
1711
interface,
1712
avahi_proto_to_af(proto),
1713
mc);
952
1714
if(ret == 0){
953
avahi_simple_poll_quit(mc.simple_poll);
1715
avahi_simple_poll_quit(simple_poll);
1716
} else {
1717
if(not add_server(ip, (in_port_t)port, interface,
1718
avahi_proto_to_af(proto),
1719
&((mandos_context*)mc)->current_server)){
1720
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1721
" list\n", name);
1722
}
954
1723
}
955
1724
}
956
1725
}
966
1735
const char *domain,
967
1736
AVAHI_GCC_UNUSED AvahiLookupResultFlags
968
1737
flags,
969
AVAHI_GCC_UNUSED void* userdata){
970
assert(b);
1738
void *mc){
1739
if(b == NULL){
1740
return;
1741
}
971
1742
972
1743
/* Called whenever a new services becomes available on the LAN or
973
1744
is removed from the LAN */
980
1751
default:
981
1752
case AVAHI_BROWSER_FAILURE:
982
1753
983
fprintf(stderr, "(Avahi browser) %s\n",
984
avahi_strerror(avahi_server_errno(mc.server)));
985
avahi_simple_poll_quit(mc.simple_poll);
1754
fprintf_plus(stderr, "(Avahi browser) %s\n",
1755
avahi_strerror(avahi_server_errno
1756
(((mandos_context*)mc)->server)));
1757
avahi_simple_poll_quit(simple_poll);
986
1758
return;
987
1759
988
1760
case AVAHI_BROWSER_NEW:
991
1763
the callback function is called the Avahi server will free the
992
1764
resolver for us. */
993
1765
994
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
995
name, type, domain, protocol, 0,
996
resolve_callback, NULL) == NULL)
997
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
998
name, avahi_strerror(avahi_server_errno(mc.server)));
1766
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1767
interface, protocol, name, type,
1768
domain, protocol, 0,
1769
resolve_callback, mc) == NULL)
1770
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1771
" %s\n", name,
1772
avahi_strerror(avahi_server_errno
1773
(((mandos_context*)mc)->server)));
999
1774
break;
1000
1775
1001
1776
case AVAHI_BROWSER_REMOVE:
1004
1779
case AVAHI_BROWSER_ALL_FOR_NOW:
1005
1780
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1006
1781
if(debug){
1007
fprintf(stderr, "No Mandos server found, still searching...\n");
1782
fprintf_plus(stderr, "No Mandos server found, still"
1783
" searching...\n");
1008
1784
}
1009
1785
break;
1010
1786
}
1011
1787
}
1012
1788
1013
/* stop main loop after sigterm has been called */
1789
/* Signal handler that stops main loop after SIGTERM */
1014
1790
static void handle_sigterm(int sig){
1015
1791
if(quit_now){
1016
1792
return;
1018
1794
quit_now = 1;
1019
1795
signal_received = sig;
1020
1796
int old_errno = errno;
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1797
/* set main loop to exit */
1798
if(simple_poll != NULL){
1799
avahi_simple_poll_quit(simple_poll);
1023
1800
}
1024
1801
errno = old_errno;
1025
1802
}
1026
1803
1804
__attribute__((nonnull, warn_unused_result))
1805
bool get_flags(const char *ifname, struct ifreq *ifr){
1806
int ret;
1807
int old_errno;
1808
1809
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1810
if(s < 0){
1811
old_errno = errno;
1812
perror_plus("socket");
1813
errno = old_errno;
1814
return false;
1815
}
1816
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1817
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1818
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1819
if(ret == -1){
1820
if(debug){
1821
old_errno = errno;
1822
perror_plus("ioctl SIOCGIFFLAGS");
1823
errno = old_errno;
1824
}
1825
if((close(s) == -1) and debug){
1826
old_errno = errno;
1827
perror_plus("close");
1828
errno = old_errno;
1829
}
1830
return false;
1831
}
1832
if((close(s) == -1) and debug){
1833
old_errno = errno;
1834
perror_plus("close");
1835
errno = old_errno;
1836
}
1837
return true;
1838
}
1839
1840
__attribute__((nonnull, warn_unused_result))
1841
bool good_flags(const char *ifname, const struct ifreq *ifr){
1842
1843
/* Reject the loopback device */
1844
if(ifr->ifr_flags & IFF_LOOPBACK){
1845
if(debug){
1846
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1847
ifname);
1848
}
1849
return false;
1850
}
1851
/* Accept point-to-point devices only if connect_to is specified */
1852
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1853
if(debug){
1854
fprintf_plus(stderr, "Accepting point-to-point interface"
1855
" \"%s\"\n", ifname);
1856
}
1857
return true;
1858
}
1859
/* Otherwise, reject non-broadcast-capable devices */
1860
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1861
if(debug){
1862
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1863
" \"%s\"\n", ifname);
1864
}
1865
return false;
1866
}
1867
/* Reject non-ARP interfaces (including dummy interfaces) */
1868
if(ifr->ifr_flags & IFF_NOARP){
1869
if(debug){
1870
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1871
ifname);
1872
}
1873
return false;
1874
}
1875
1876
/* Accept this device */
1877
if(debug){
1878
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1879
}
1880
return true;
1881
}
1882
1027
1883
/*
1028
1884
* This function determines if a directory entry in /sys/class/net
1029
1885
* corresponds to an acceptable network device.
1030
1886
* (This function is passed to scandir(3) as a filter function.)
1031
1887
*/
1888
__attribute__((nonnull, warn_unused_result))
1032
1889
int good_interface(const struct dirent *if_entry){
1033
ssize_t ssret;
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1036
if_entry->d_name);
1037
if(ret < 0){
1038
perror("asprintf");
1039
return 0;
1040
}
1041
1890
if(if_entry->d_name[0] == '.'){
1042
1891
return 0;
1043
1892
}
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1045
if(flags_fd == -1){
1046
perror("open");
1047
return 0;
1048
}
1049
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1050
/* read line from flags_fd */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1052
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1053
flagstring[(size_t)to_read] = '\0';
1054
if(flagstring == NULL){
1055
perror("malloc");
1056
close(flags_fd);
1057
return 0;
1058
}
1059
while(to_read > 0){
1060
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1061
(size_t)to_read));
1062
if(ssret == -1){
1063
perror("read");
1064
free(flagstring);
1065
close(flags_fd);
1066
return 0;
1067
}
1068
to_read -= ssret;
1069
if(ssret == 0){
1893
1894
struct ifreq ifr;
1895
if(not get_flags(if_entry->d_name, &ifr)){
1896
if(debug){
1897
fprintf_plus(stderr, "Failed to get flags for interface "
1898
"\"%s\"\n", if_entry->d_name);
1899
}
1900
return 0;
1901
}
1902
1903
if(not good_flags(if_entry->d_name, &ifr)){
1904
return 0;
1905
}
1906
return 1;
1907
}
1908
1909
/*
1910
* This function determines if a network interface is up.
1911
*/
1912
__attribute__((nonnull, warn_unused_result))
1913
bool interface_is_up(const char *interface){
1914
struct ifreq ifr;
1915
if(not get_flags(interface, &ifr)){
1916
if(debug){
1917
fprintf_plus(stderr, "Failed to get flags for interface "
1918
"\"%s\"\n", interface);
1919
}
1920
return false;
1921
}
1922
1923
return (bool)(ifr.ifr_flags & IFF_UP);
1924
}
1925
1926
/*
1927
* This function determines if a network interface is running
1928
*/
1929
__attribute__((nonnull, warn_unused_result))
1930
bool interface_is_running(const char *interface){
1931
struct ifreq ifr;
1932
if(not get_flags(interface, &ifr)){
1933
if(debug){
1934
fprintf_plus(stderr, "Failed to get flags for interface "
1935
"\"%s\"\n", interface);
1936
}
1937
return false;
1938
}
1939
1940
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1941
}
1942
1943
__attribute__((nonnull, pure, warn_unused_result))
1944
int notdotentries(const struct dirent *direntry){
1945
/* Skip "." and ".." */
1946
if(direntry->d_name[0] == '.'
1947
and (direntry->d_name[1] == '\0'
1948
or (direntry->d_name[1] == '.'
1949
and direntry->d_name[2] == '\0'))){
1950
return 0;
1951
}
1952
return 1;
1953
}
1954
1955
/* Is this directory entry a runnable program? */
1956
__attribute__((nonnull, warn_unused_result))
1957
int runnable_hook(const struct dirent *direntry){
1958
int ret;
1959
size_t sret;
1960
struct stat st;
1961
1962
if((direntry->d_name)[0] == '\0'){
1963
/* Empty name? */
1964
return 0;
1965
}
1966
1967
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1968
"abcdefghijklmnopqrstuvwxyz"
1969
"0123456789"
1970
"_.-");
1971
if((direntry->d_name)[sret] != '\0'){
1972
/* Contains non-allowed characters */
1973
if(debug){
1974
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1975
direntry->d_name);
1976
}
1977
return 0;
1978
}
1979
1980
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1981
if(ret == -1){
1982
if(debug){
1983
perror_plus("Could not stat hook");
1984
}
1985
return 0;
1986
}
1987
if(not (S_ISREG(st.st_mode))){
1988
/* Not a regular file */
1989
if(debug){
1990
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1991
direntry->d_name);
1992
}
1993
return 0;
1994
}
1995
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1996
/* Not executable */
1997
if(debug){
1998
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1999
direntry->d_name);
2000
}
2001
return 0;
2002
}
2003
if(debug){
2004
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
2005
direntry->d_name);
2006
}
2007
return 1;
2008
}
2009
2010
__attribute__((nonnull, warn_unused_result))
2011
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
2012
mandos_context *mc){
2013
int ret;
2014
struct timespec now;
2015
struct timespec waited_time;
2016
intmax_t block_time;
2017
2018
while(true){
2019
if(mc->current_server == NULL){
2020
if(debug){
2021
fprintf_plus(stderr, "Wait until first server is found."
2022
" No timeout!\n");
2023
}
2024
ret = avahi_simple_poll_iterate(s, -1);
2025
} else {
2026
if(debug){
2027
fprintf_plus(stderr, "Check current_server if we should run"
2028
" it, or wait\n");
2029
}
2030
/* the current time */
2031
ret = clock_gettime(CLOCK_MONOTONIC, &now);
2032
if(ret == -1){
2033
perror_plus("clock_gettime");
2034
return -1;
2035
}
2036
/* Calculating in ms how long time between now and server
2037
who we visted longest time ago. Now - last seen. */
2038
waited_time.tv_sec = (now.tv_sec
2039
- mc->current_server->last_seen.tv_sec);
2040
waited_time.tv_nsec = (now.tv_nsec
2041
- mc->current_server->last_seen.tv_nsec);
2042
/* total time is 10s/10,000ms.
2043
Converting to s from ms by dividing by 1,000,
2044
and ns to ms by dividing by 1,000,000. */
2045
block_time = ((retry_interval
2046
- ((intmax_t)waited_time.tv_sec * 1000))
2047
- ((intmax_t)waited_time.tv_nsec / 1000000));
2048
2049
if(debug){
2050
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
2051
block_time);
2052
}
2053
2054
if(block_time <= 0){
2055
ret = start_mandos_communication(mc->current_server->ip,
2056
mc->current_server->port,
2057
mc->current_server->if_index,
2058
mc->current_server->af, mc);
2059
if(ret == 0){
2060
avahi_simple_poll_quit(s);
2061
return 0;
2062
}
2063
ret = clock_gettime(CLOCK_MONOTONIC,
2064
&mc->current_server->last_seen);
2065
if(ret == -1){
2066
perror_plus("clock_gettime");
2067
return -1;
2068
}
2069
mc->current_server = mc->current_server->next;
2070
block_time = 0; /* Call avahi to find new Mandos
2071
servers, but don't block */
2072
}
2073
2074
ret = avahi_simple_poll_iterate(s, (int)block_time);
2075
}
2076
if(ret != 0){
2077
if(ret > 0 or errno != EINTR){
2078
return (ret != 1) ? ret : 0;
2079
}
2080
}
2081
}
2082
}
2083
2084
__attribute__((nonnull))
2085
void run_network_hooks(const char *mode, const char *interface,
2086
const float delay){
2087
struct dirent **direntries = NULL;
2088
if(hookdir_fd == -1){
2089
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2090
| O_CLOEXEC);
2091
if(hookdir_fd == -1){
2092
if(errno == ENOENT){
2093
if(debug){
2094
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2095
" found\n", hookdir);
2096
}
2097
} else {
2098
perror_plus("open");
2099
}
2100
return;
2101
}
2102
}
2103
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2104
if(devnull == -1){
2105
perror_plus("open(\"/dev/null\", O_RDONLY)");
2106
return;
2107
}
2108
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2109
runnable_hook, alphasort);
2110
if(numhooks == -1){
2111
perror_plus("scandir");
2112
close(devnull);
2113
return;
2114
}
2115
struct dirent *direntry;
2116
int ret;
2117
for(int i = 0; i < numhooks; i++){
2118
direntry = direntries[i];
2119
if(debug){
2120
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2121
direntry->d_name);
2122
}
2123
pid_t hook_pid = fork();
2124
if(hook_pid == 0){
2125
/* Child */
2126
/* Raise privileges */
2127
errno = raise_privileges_permanently();
2128
if(errno != 0){
2129
perror_plus("Failed to raise privileges");
2130
_exit(EX_NOPERM);
2131
}
2132
/* Set group */
2133
errno = 0;
2134
ret = setgid(0);
2135
if(ret == -1){
2136
perror_plus("setgid");
2137
_exit(EX_NOPERM);
2138
}
2139
/* Reset supplementary groups */
2140
errno = 0;
2141
ret = setgroups(0, NULL);
2142
if(ret == -1){
2143
perror_plus("setgroups");
2144
_exit(EX_NOPERM);
2145
}
2146
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2147
if(ret == -1){
2148
perror_plus("setenv");
2149
_exit(EX_OSERR);
2150
}
2151
ret = setenv("DEVICE", interface, 1);
2152
if(ret == -1){
2153
perror_plus("setenv");
2154
_exit(EX_OSERR);
2155
}
2156
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2157
if(ret == -1){
2158
perror_plus("setenv");
2159
_exit(EX_OSERR);
2160
}
2161
ret = setenv("MODE", mode, 1);
2162
if(ret == -1){
2163
perror_plus("setenv");
2164
_exit(EX_OSERR);
2165
}
2166
char *delaystring;
2167
ret = asprintf(&delaystring, "%f", (double)delay);
2168
if(ret == -1){
2169
perror_plus("asprintf");
2170
_exit(EX_OSERR);
2171
}
2172
ret = setenv("DELAY", delaystring, 1);
2173
if(ret == -1){
2174
free(delaystring);
2175
perror_plus("setenv");
2176
_exit(EX_OSERR);
2177
}
2178
free(delaystring);
2179
if(connect_to != NULL){
2180
ret = setenv("CONNECT", connect_to, 1);
2181
if(ret == -1){
2182
perror_plus("setenv");
2183
_exit(EX_OSERR);
2184
}
2185
}
2186
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2187
direntry->d_name,
2188
O_RDONLY));
2189
if(hook_fd == -1){
2190
perror_plus("openat");
2191
_exit(EXIT_FAILURE);
2192
}
2193
if(close(hookdir_fd) == -1){
2194
perror_plus("close");
2195
_exit(EXIT_FAILURE);
2196
}
2197
ret = dup2(devnull, STDIN_FILENO);
2198
if(ret == -1){
2199
perror_plus("dup2(devnull, STDIN_FILENO)");
2200
_exit(EX_OSERR);
2201
}
2202
ret = close(devnull);
2203
if(ret == -1){
2204
perror_plus("close");
2205
_exit(EX_OSERR);
2206
}
2207
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2208
if(ret == -1){
2209
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2210
_exit(EX_OSERR);
2211
}
2212
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2213
environ) == -1){
2214
perror_plus("fexecve");
2215
_exit(EXIT_FAILURE);
2216
}
2217
} else {
2218
if(hook_pid == -1){
2219
perror_plus("fork");
2220
free(direntry);
2221
continue;
2222
}
2223
int status;
2224
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2225
perror_plus("waitpid");
2226
free(direntry);
2227
continue;
2228
}
2229
if(WIFEXITED(status)){
2230
if(WEXITSTATUS(status) != 0){
2231
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2232
" with status %d\n", direntry->d_name,
2233
WEXITSTATUS(status));
2234
free(direntry);
2235
continue;
2236
}
2237
} else if(WIFSIGNALED(status)){
2238
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2239
" signal %d\n", direntry->d_name,
2240
WTERMSIG(status));
2241
free(direntry);
2242
continue;
2243
} else {
2244
fprintf_plus(stderr, "Warning: network hook \"%s\""
2245
" crashed\n", direntry->d_name);
2246
free(direntry);
2247
continue;
2248
}
2249
}
2250
if(debug){
2251
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2252
direntry->d_name);
2253
}
2254
free(direntry);
2255
}
2256
free(direntries);
2257
if(close(hookdir_fd) == -1){
2258
perror_plus("close");
2259
} else {
2260
hookdir_fd = -1;
2261
}
2262
close(devnull);
2263
}
2264
2265
__attribute__((nonnull, warn_unused_result))
2266
int bring_up_interface(const char *const interface,
2267
const float delay){
2268
int old_errno = errno;
2269
int ret;
2270
struct ifreq network;
2271
unsigned int if_index = if_nametoindex(interface);
2272
if(if_index == 0){
2273
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2274
errno = old_errno;
2275
return ENXIO;
2276
}
2277
2278
if(quit_now){
2279
errno = old_errno;
2280
return EINTR;
2281
}
2282
2283
if(not interface_is_up(interface)){
2284
int ret_errno = 0;
2285
int ioctl_errno = 0;
2286
if(not get_flags(interface, &network)){
2287
ret_errno = errno;
2288
fprintf_plus(stderr, "Failed to get flags for interface "
2289
"\"%s\"\n", interface);
2290
errno = old_errno;
2291
return ret_errno;
2292
}
2293
network.ifr_flags |= IFF_UP; /* set flag */
2294
2295
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2296
if(sd == -1){
2297
ret_errno = errno;
2298
perror_plus("socket");
2299
errno = old_errno;
2300
return ret_errno;
2301
}
2302
2303
if(quit_now){
2304
ret = close(sd);
2305
if(ret == -1){
2306
perror_plus("close");
2307
}
2308
errno = old_errno;
2309
return EINTR;
2310
}
2311
2312
if(debug){
2313
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2314
interface);
2315
}
2316
2317
/* Raise privileges */
2318
ret_errno = raise_privileges();
2319
if(ret_errno != 0){
2320
errno = ret_errno;
2321
perror_plus("Failed to raise privileges");
2322
}
2323
2324
#ifdef __linux__
2325
int ret_linux;
2326
bool restore_loglevel = false;
2327
if(ret_errno == 0){
2328
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2329
messages about the network interface to mess up the prompt */
2330
ret_linux = klogctl(8, NULL, 5);
2331
if(ret_linux == -1){
2332
perror_plus("klogctl");
2333
} else {
2334
restore_loglevel = true;
2335
}
2336
}
2337
#endif /* __linux__ */
2338
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2339
ioctl_errno = errno;
2340
#ifdef __linux__
2341
if(restore_loglevel){
2342
ret_linux = klogctl(7, NULL, 0);
2343
if(ret_linux == -1){
2344
perror_plus("klogctl");
2345
}
2346
}
2347
#endif /* __linux__ */
2348
2349
/* If raise_privileges() succeeded above */
2350
if(ret_errno == 0){
2351
/* Lower privileges */
2352
ret_errno = lower_privileges();
2353
if(ret_errno != 0){
2354
errno = ret_errno;
2355
perror_plus("Failed to lower privileges");
2356
}
2357
}
2358
2359
/* Close the socket */
2360
ret = close(sd);
2361
if(ret == -1){
2362
perror_plus("close");
2363
}
2364
2365
if(ret_setflags == -1){
2366
errno = ioctl_errno;
2367
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2368
errno = old_errno;
2369
return ioctl_errno;
2370
}
2371
} else if(debug){
2372
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2373
interface);
2374
}
2375
2376
/* Sleep checking until interface is running.
2377
Check every 0.25s, up to total time of delay */
2378
for(int i = 0; i < delay * 4; i++){
2379
if(interface_is_running(interface)){
1070
2380
break;
1071
2381
}
1072
}
1073
close(flags_fd);
1074
intmax_t tmpmax;
1075
char *tmp;
1076
errno = 0;
1077
tmpmax = strtoimax(flagstring, &tmp, 0);
1078
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1079
and not (isspace(*tmp)))
1080
or tmpmax != (ifreq_flags)tmpmax){
1081
if(debug){
1082
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1083
flagstring, if_entry->d_name);
1084
}
1085
free(flagstring);
1086
return 0;
1087
}
1088
free(flagstring);
1089
ifreq_flags flags = (ifreq_flags)tmpmax;
1090
/* Reject the loopback device */
1091
if(flags & IFF_LOOPBACK){
1092
if(debug){
1093
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1094
if_entry->d_name);
1095
}
1096
return 0;
1097
}
1098
/* Accept point-to-point devices only if connect_to is specified */
1099
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1100
if(debug){
1101
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1102
if_entry->d_name);
1103
}
1104
return 1;
1105
}
1106
/* Otherwise, reject non-broadcast-capable devices */
1107
if(not (flags & IFF_BROADCAST)){
1108
if(debug){
1109
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1110
if_entry->d_name);
1111
}
1112
return 0;
1113
}
1114
/* Accept this device */
1115
if(debug){
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1117
if_entry->d_name);
1118
}
1119
return 1;
2382
struct timespec sleeptime = { .tv_nsec = 250000000 };
2383
ret = nanosleep(&sleeptime, NULL);
2384
if(ret == -1 and errno != EINTR){
2385
perror_plus("nanosleep");
2386
}
2387
}
2388
2389
errno = old_errno;
2390
return 0;
2391
}
2392
2393
__attribute__((nonnull, warn_unused_result))
2394
int take_down_interface(const char *const interface){
2395
int old_errno = errno;
2396
struct ifreq network;
2397
unsigned int if_index = if_nametoindex(interface);
2398
if(if_index == 0){
2399
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2400
errno = old_errno;
2401
return ENXIO;
2402
}
2403
if(interface_is_up(interface)){
2404
int ret_errno = 0;
2405
int ioctl_errno = 0;
2406
if(not get_flags(interface, &network) and debug){
2407
ret_errno = errno;
2408
fprintf_plus(stderr, "Failed to get flags for interface "
2409
"\"%s\"\n", interface);
2410
errno = old_errno;
2411
return ret_errno;
2412
}
2413
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2414
2415
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2416
if(sd == -1){
2417
ret_errno = errno;
2418
perror_plus("socket");
2419
errno = old_errno;
2420
return ret_errno;
2421
}
2422
2423
if(debug){
2424
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2425
interface);
2426
}
2427
2428
/* Raise privileges */
2429
ret_errno = raise_privileges();
2430
if(ret_errno != 0){
2431
errno = ret_errno;
2432
perror_plus("Failed to raise privileges");
2433
}
2434
2435
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2436
ioctl_errno = errno;
2437
2438
/* If raise_privileges() succeeded above */
2439
if(ret_errno == 0){
2440
/* Lower privileges */
2441
ret_errno = lower_privileges();
2442
if(ret_errno != 0){
2443
errno = ret_errno;
2444
perror_plus("Failed to lower privileges");
2445
}
2446
}
2447
2448
/* Close the socket */
2449
int ret = close(sd);
2450
if(ret == -1){
2451
perror_plus("close");
2452
}
2453
2454
if(ret_setflags == -1){
2455
errno = ioctl_errno;
2456
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2457
errno = old_errno;
2458
return ioctl_errno;
2459
}
2460
} else if(debug){
2461
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2462
interface);
2463
}
2464
2465
errno = old_errno;
2466
return 0;
1120
2467
}
1121
2468
1122
2469
int main(int argc, char *argv[]){
2470
mandos_context mc = { .server = NULL, .dh_bits = 0,
2471
#if GNUTLS_VERSION_NUMBER >= 0x030606
2472
.priority = "SECURE128:!CTYPE-X.509"
2473
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2474
":%PROFILE_ULTRA",
2475
#elif GNUTLS_VERSION_NUMBER < 0x030600
2476
.priority = "SECURE256:!CTYPE-X.509"
2477
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2478
#else
2479
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2480
#endif
2481
.current_server = NULL, .interfaces = NULL,
2482
.interfaces_size = 0 };
1123
2483
AvahiSServiceBrowser *sb = NULL;
1124
int error;
2484
error_t ret_errno;
1125
2485
int ret;
1126
2486
intmax_t tmpmax;
1127
2487
char *tmp;
1128
2488
int exitcode = EXIT_SUCCESS;
1129
const char *interface = "";
1130
struct ifreq network;
1131
int sd = -1;
1132
bool take_down_interface = false;
1133
uid_t uid;
1134
gid_t gid;
1135
char tempdir[] = "/tmp/mandosXXXXXX";
1136
bool tempdir_created = false;
2489
char *interfaces_to_take_down = NULL;
2490
size_t interfaces_to_take_down_size = 0;
2491
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2492
char old_tempdir[] = "/tmp/mandosXXXXXX";
2493
char *tempdir = NULL;
1137
2494
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1138
2495
const char *seckey = PATHDIR "/" SECKEY;
1139
2496
const char *pubkey = PATHDIR "/" PUBKEY;
2497
#if GNUTLS_VERSION_NUMBER >= 0x030606
2498
const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;
2499
const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;
2500
#endif
2501
const char *dh_params_file = NULL;
2502
char *interfaces_hooks = NULL;
1140
2503
1141
2504
bool gnutls_initialized = false;
1142
2505
bool gpgme_initialized = false;
1143
2506
float delay = 2.5f;
2507
double retry_interval = 10; /* 10s between trying a server and
2508
retrying the same server again */
1144
2509
1145
2510
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1146
2511
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1152
2517
errno = 0;
1153
2518
ret = setgid(gid);
1154
2519
if(ret == -1){
1155
perror("setgid");
2520
perror_plus("setgid");
1156
2521
}
1157
2522
1158
2523
/* Lower user privileges (temporarily) */
1159
2524
errno = 0;
1160
2525
ret = seteuid(uid);
1161
2526
if(ret == -1){
1162
perror("seteuid");
2527
perror_plus("seteuid");
1163
2528
}
1164
2529
1165
2530
if(quit_now){
1186
2551
{ .name = "pubkey", .key = 'p',
1187
2552
.arg = "FILE",
1188
2553
.doc = "OpenPGP public key file base name",
1189
.group = 2 },
2554
.group = 1 },
2555
{ .name = "tls-privkey", .key = 't',
2556
.arg = "FILE",
2557
#if GNUTLS_VERSION_NUMBER >= 0x030606
2558
.doc = "TLS private key file base name",
2559
#else
2560
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2561
#endif
2562
.group = 1 },
2563
{ .name = "tls-pubkey", .key = 'T',
2564
.arg = "FILE",
2565
#if GNUTLS_VERSION_NUMBER >= 0x030606
2566
.doc = "TLS public key file base name",
2567
#else
2568
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2569
#endif
2570
.group = 1 },
1190
2571
{ .name = "dh-bits", .key = 129,
1191
2572
.arg = "BITS",
1192
2573
.doc = "Bit length of the prime number used in the"
1193
2574
" Diffie-Hellman key exchange",
1194
2575
.group = 2 },
2576
{ .name = "dh-params", .key = 134,
2577
.arg = "FILE",
2578
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2579
" for the Diffie-Hellman key exchange",
2580
.group = 2 },
1195
2581
{ .name = "priority", .key = 130,
1196
2582
.arg = "STRING",
1197
2583
.doc = "GnuTLS priority string for the TLS handshake",
1200
2586
.arg = "SECONDS",
1201
2587
.doc = "Maximum delay to wait for interface startup",
1202
2588
.group = 2 },
2589
{ .name = "retry", .key = 132,
2590
.arg = "SECONDS",
2591
.doc = "Retry interval used when denied by the Mandos server",
2592
.group = 2 },
2593
{ .name = "network-hook-dir", .key = 133,
2594
.arg = "DIR",
2595
.doc = "Directory where network hooks are located",
2596
.group = 2 },
1203
2597
/*
1204
2598
* These reproduce what we would get without ARGP_NO_HELP
1205
2599
*/
1223
2617
connect_to = arg;
1224
2618
break;
1225
2619
case 'i': /* --interface */
1226
interface = arg;
2620
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2621
arg, (int)',');
2622
if(ret_errno != 0){
2623
argp_error(state, "%s", strerror(ret_errno));
2624
}
1227
2625
break;
1228
2626
case 's': /* --seckey */
1229
2627
seckey = arg;
1231
2629
case 'p': /* --pubkey */
1232
2630
pubkey = arg;
1233
2631
break;
2632
case 't': /* --tls-privkey */
2633
#if GNUTLS_VERSION_NUMBER >= 0x030606
2634
tls_privkey = arg;
2635
#endif
2636
break;
2637
case 'T': /* --tls-pubkey */
2638
#if GNUTLS_VERSION_NUMBER >= 0x030606
2639
tls_pubkey = arg;
2640
#endif
2641
break;
1234
2642
case 129: /* --dh-bits */
1235
2643
errno = 0;
1236
2644
tmpmax = strtoimax(arg, &tmp, 10);
1240
2648
}
1241
2649
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1242
2650
break;
2651
case 134: /* --dh-params */
2652
dh_params_file = arg;
2653
break;
1243
2654
case 130: /* --priority */
1244
2655
mc.priority = arg;
1245
2656
break;
1249
2660
if(errno != 0 or tmp == arg or *tmp != '\0'){
1250
2661
argp_error(state, "Bad delay");
1251
2662
}
2663
case 132: /* --retry */
2664
errno = 0;
2665
retry_interval = strtod(arg, &tmp);
2666
if(errno != 0 or tmp == arg or *tmp != '\0'
2667
or (retry_interval * 1000) > INT_MAX
2668
or retry_interval < 0){
2669
argp_error(state, "Bad retry interval");
2670
}
2671
break;
2672
case 133: /* --network-hook-dir */
2673
hookdir = arg;
1252
2674
break;
1253
2675
/*
1254
2676
* These reproduce what we would get without ARGP_NO_HELP
1257
2679
argp_state_help(state, state->out_stream,
1258
2680
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1259
2681
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2682
__builtin_unreachable();
1260
2683
case -3: /* --usage */
1261
2684
argp_state_help(state, state->out_stream,
1262
2685
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2686
__builtin_unreachable();
1263
2687
case 'V': /* --version */
1264
fprintf(state->out_stream, "%s\n", argp_program_version);
2688
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1265
2689
exit(argp_err_exit_status);
1266
2690
break;
1267
2691
default:
1274
2698
.args_doc = "",
1275
2699
.doc = "Mandos client -- Get and decrypt"
1276
2700
" passwords from a Mandos server" };
1277
ret = argp_parse(&argp, argc, argv,
1278
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1279
switch(ret){
2701
ret_errno = argp_parse(&argp, argc, argv,
2702
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2703
switch(ret_errno){
1280
2704
case 0:
1281
2705
break;
1282
2706
case ENOMEM:
1283
2707
default:
1284
errno = ret;
1285
perror("argp_parse");
2708
errno = ret_errno;
2709
perror_plus("argp_parse");
1286
2710
exitcode = EX_OSERR;
1287
2711
goto end;
1288
2712
case EINVAL:
1291
2715
}
1292
2716
}
1293
2717
2718
{
2719
/* Work around Debian bug #633582:
2720
<https://bugs.debian.org/633582> */
2721
2722
/* Re-raise privileges */
2723
ret = raise_privileges();
2724
if(ret != 0){
2725
errno = ret;
2726
perror_plus("Failed to raise privileges");
2727
} else {
2728
struct stat st;
2729
2730
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2731
int seckey_fd = open(seckey, O_RDONLY);
2732
if(seckey_fd == -1){
2733
perror_plus("open");
2734
} else {
2735
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2736
if(ret == -1){
2737
perror_plus("fstat");
2738
} else {
2739
if(S_ISREG(st.st_mode)
2740
and st.st_uid == 0 and st.st_gid == 0){
2741
ret = fchown(seckey_fd, uid, gid);
2742
if(ret == -1){
2743
perror_plus("fchown");
2744
}
2745
}
2746
}
2747
close(seckey_fd);
2748
}
2749
}
2750
2751
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2752
int pubkey_fd = open(pubkey, O_RDONLY);
2753
if(pubkey_fd == -1){
2754
perror_plus("open");
2755
} else {
2756
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2757
if(ret == -1){
2758
perror_plus("fstat");
2759
} else {
2760
if(S_ISREG(st.st_mode)
2761
and st.st_uid == 0 and st.st_gid == 0){
2762
ret = fchown(pubkey_fd, uid, gid);
2763
if(ret == -1){
2764
perror_plus("fchown");
2765
}
2766
}
2767
}
2768
close(pubkey_fd);
2769
}
2770
}
2771
2772
if(dh_params_file != NULL
2773
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2774
int dhparams_fd = open(dh_params_file, O_RDONLY);
2775
if(dhparams_fd == -1){
2776
perror_plus("open");
2777
} else {
2778
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2779
if(ret == -1){
2780
perror_plus("fstat");
2781
} else {
2782
if(S_ISREG(st.st_mode)
2783
and st.st_uid == 0 and st.st_gid == 0){
2784
ret = fchown(dhparams_fd, uid, gid);
2785
if(ret == -1){
2786
perror_plus("fchown");
2787
}
2788
}
2789
}
2790
close(dhparams_fd);
2791
}
2792
}
2793
2794
/* Lower privileges */
2795
ret = lower_privileges();
2796
if(ret != 0){
2797
errno = ret;
2798
perror_plus("Failed to lower privileges");
2799
}
2800
}
2801
}
2802
2803
/* Remove invalid interface names (except "none") */
2804
{
2805
char *interface = NULL;
2806
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2807
interface))){
2808
if(strcmp(interface, "none") != 0
2809
and if_nametoindex(interface) == 0){
2810
if(interface[0] != '\0'){
2811
fprintf_plus(stderr, "Not using nonexisting interface"
2812
" \"%s\"\n", interface);
2813
}
2814
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2815
interface = NULL;
2816
}
2817
}
2818
}
2819
2820
/* Run network hooks */
2821
{
2822
if(mc.interfaces != NULL){
2823
interfaces_hooks = malloc(mc.interfaces_size);
2824
if(interfaces_hooks == NULL){
2825
perror_plus("malloc");
2826
goto end;
2827
}
2828
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2829
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2830
}
2831
run_network_hooks("start", interfaces_hooks != NULL ?
2832
interfaces_hooks : "", delay);
2833
}
2834
1294
2835
if(not debug){
1295
2836
avahi_set_log_function(empty_log);
1296
2837
}
1297
1298
if(interface[0] == '\0'){
1299
struct dirent **direntries;
1300
ret = scandir(sys_class_net, &direntries, good_interface,
1301
alphasort);
1302
if(ret >= 1){
1303
/* Pick the first good interface */
1304
interface = strdup(direntries[0]->d_name);
1305
if(debug){
1306
fprintf(stderr, "Using interface \"%s\"\n", interface);
1307
}
1308
if(interface == NULL){
1309
perror("malloc");
1310
free(direntries);
1311
exitcode = EXIT_FAILURE;
1312
goto end;
1313
}
1314
free(direntries);
1315
} else {
1316
free(direntries);
1317
fprintf(stderr, "Could not find a network interface\n");
1318
exitcode = EXIT_FAILURE;
1319
goto end;
1320
}
1321
}
1322
2838
1323
2839
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1324
2840
from the signal handler */
1325
2841
/* Initialize the pseudo-RNG for Avahi */
1326
2842
srand((unsigned int) time(NULL));
1327
mc.simple_poll = avahi_simple_poll_new();
1328
if(mc.simple_poll == NULL){
1329
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2843
simple_poll = avahi_simple_poll_new();
2844
if(simple_poll == NULL){
2845
fprintf_plus(stderr,
2846
"Avahi: Failed to create simple poll object.\n");
1330
2847
exitcode = EX_UNAVAILABLE;
1331
2848
goto end;
1332
2849
}
1334
2851
sigemptyset(&sigterm_action.sa_mask);
1335
2852
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1336
2853
if(ret == -1){
1337
perror("sigaddset");
2854
perror_plus("sigaddset");
1338
2855
exitcode = EX_OSERR;
1339
2856
goto end;
1340
2857
}
1341
2858
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1342
2859
if(ret == -1){
1343
perror("sigaddset");
2860
perror_plus("sigaddset");
1344
2861
exitcode = EX_OSERR;
1345
2862
goto end;
1346
2863
}
1347
2864
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1348
2865
if(ret == -1){
1349
perror("sigaddset");
2866
perror_plus("sigaddset");
1350
2867
exitcode = EX_OSERR;
1351
2868
goto end;
1352
2869
}
1356
2873
*/
1357
2874
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1358
2875
if(ret == -1){
1359
perror("sigaction");
2876
perror_plus("sigaction");
1360
2877
return EX_OSERR;
1361
2878
}
1362
2879
if(old_sigterm_action.sa_handler != SIG_IGN){
1363
2880
ret = sigaction(SIGINT, &sigterm_action, NULL);
1364
2881
if(ret == -1){
1365
perror("sigaction");
2882
perror_plus("sigaction");
1366
2883
exitcode = EX_OSERR;
1367
2884
goto end;
1368
2885
}
1369
2886
}
1370
2887
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1371
2888
if(ret == -1){
1372
perror("sigaction");
2889
perror_plus("sigaction");
1373
2890
return EX_OSERR;
1374
2891
}
1375
2892
if(old_sigterm_action.sa_handler != SIG_IGN){
1376
2893
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1377
2894
if(ret == -1){
1378
perror("sigaction");
2895
perror_plus("sigaction");
1379
2896
exitcode = EX_OSERR;
1380
2897
goto end;
1381
2898
}
1382
2899
}
1383
2900
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1384
2901
if(ret == -1){
1385
perror("sigaction");
2902
perror_plus("sigaction");
1386
2903
return EX_OSERR;
1387
2904
}
1388
2905
if(old_sigterm_action.sa_handler != SIG_IGN){
1389
2906
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1390
2907
if(ret == -1){
1391
perror("sigaction");
1392
exitcode = EX_OSERR;
1393
goto end;
1394
}
1395
}
1396
1397
/* If the interface is down, bring it up */
1398
if(strcmp(interface, "none") != 0){
1399
if_index = (AvahiIfIndex) if_nametoindex(interface);
1400
if(if_index == 0){
1401
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1402
exitcode = EX_UNAVAILABLE;
1403
goto end;
1404
}
1405
1406
if(quit_now){
1407
goto end;
1408
}
1409
1410
/* Re-raise priviliges */
1411
errno = 0;
1412
ret = seteuid(0);
1413
if(ret == -1){
1414
perror("seteuid");
1415
}
1416
1417
#ifdef __linux__
1418
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1419
messages about the network interface to mess up the prompt */
1420
ret = klogctl(8, NULL, 5);
1421
bool restore_loglevel = true;
1422
if(ret == -1){
1423
restore_loglevel = false;
1424
perror("klogctl");
1425
}
1426
#endif /* __linux__ */
1427
1428
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1429
if(sd < 0){
1430
perror("socket");
1431
exitcode = EX_OSERR;
1432
#ifdef __linux__
1433
if(restore_loglevel){
1434
ret = klogctl(7, NULL, 0);
1435
if(ret == -1){
1436
perror("klogctl");
1437
}
1438
}
1439
#endif /* __linux__ */
1440
/* Lower privileges */
1441
errno = 0;
1442
ret = seteuid(uid);
1443
if(ret == -1){
1444
perror("seteuid");
1445
}
1446
goto end;
1447
}
1448
strcpy(network.ifr_name, interface);
1449
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1450
if(ret == -1){
1451
perror("ioctl SIOCGIFFLAGS");
1452
#ifdef __linux__
1453
if(restore_loglevel){
1454
ret = klogctl(7, NULL, 0);
1455
if(ret == -1){
1456
perror("klogctl");
1457
}
1458
}
1459
#endif /* __linux__ */
1460
exitcode = EX_OSERR;
1461
/* Lower privileges */
1462
errno = 0;
1463
ret = seteuid(uid);
1464
if(ret == -1){
1465
perror("seteuid");
1466
}
1467
goto end;
1468
}
1469
if((network.ifr_flags & IFF_UP) == 0){
1470
network.ifr_flags |= IFF_UP;
1471
take_down_interface = true;
1472
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1473
if(ret == -1){
1474
take_down_interface = false;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1476
exitcode = EX_OSERR;
1477
#ifdef __linux__
1478
if(restore_loglevel){
1479
ret = klogctl(7, NULL, 0);
1480
if(ret == -1){
1481
perror("klogctl");
2908
perror_plus("sigaction");
2909
exitcode = EX_OSERR;
2910
goto end;
2911
}
2912
}
2913
2914
/* If no interfaces were specified, make a list */
2915
if(mc.interfaces == NULL){
2916
struct dirent **direntries = NULL;
2917
/* Look for any good interfaces */
2918
ret = scandir(sys_class_net, &direntries, good_interface,
2919
alphasort);
2920
if(ret >= 1){
2921
/* Add all found interfaces to interfaces list */
2922
for(int i = 0; i < ret; ++i){
2923
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2924
direntries[i]->d_name);
2925
if(ret_errno != 0){
2926
errno = ret_errno;
2927
perror_plus("argz_add");
2928
free(direntries[i]);
2929
continue;
2930
}
2931
if(debug){
2932
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2933
direntries[i]->d_name);
2934
}
2935
free(direntries[i]);
2936
}
2937
free(direntries);
2938
} else {
2939
if(ret == 0){
2940
free(direntries);
2941
}
2942
fprintf_plus(stderr, "Could not find a network interface\n");
2943
exitcode = EXIT_FAILURE;
2944
goto end;
2945
}
2946
}
2947
2948
/* Bring up interfaces which are down, and remove any "none"s */
2949
{
2950
char *interface = NULL;
2951
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2952
interface))){
2953
/* If interface name is "none", stop bringing up interfaces.
2954
Also remove all instances of "none" from the list */
2955
if(strcmp(interface, "none") == 0){
2956
argz_delete(&mc.interfaces, &mc.interfaces_size,
2957
interface);
2958
interface = NULL;
2959
while((interface = argz_next(mc.interfaces,
2960
mc.interfaces_size, interface))){
2961
if(strcmp(interface, "none") == 0){
2962
argz_delete(&mc.interfaces, &mc.interfaces_size,
2963
interface);
2964
interface = NULL;
1482
2965
}
1483
2966
}
1484
#endif /* __linux__ */
1485
/* Lower privileges */
1486
errno = 0;
1487
ret = seteuid(uid);
1488
if(ret == -1){
1489
perror("seteuid");
1490
}
1491
goto end;
1492
}
1493
}
1494
/* sleep checking until interface is running */
1495
for(int i=0; i < delay * 4; i++){
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1497
if(ret == -1){
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_RUNNING){
1500
2967
break;
1501
2968
}
1502
struct timespec sleeptime = { .tv_nsec = 250000000 };
1503
ret = nanosleep(&sleeptime, NULL);
1504
if(ret == -1 and errno != EINTR){
1505
perror("nanosleep");
1506
}
1507
}
1508
if(not take_down_interface){
1509
/* We won't need the socket anymore */
1510
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1511
if(ret == -1){
1512
perror("close");
1513
}
1514
}
1515
#ifdef __linux__
1516
if(restore_loglevel){
1517
/* Restores kernel loglevel to default */
1518
ret = klogctl(7, NULL, 0);
1519
if(ret == -1){
1520
perror("klogctl");
1521
}
1522
}
1523
#endif /* __linux__ */
1524
/* Lower privileges */
1525
errno = 0;
1526
if(take_down_interface){
1527
/* Lower privileges */
1528
ret = seteuid(uid);
1529
if(ret == -1){
1530
perror("seteuid");
1531
}
1532
} else {
1533
/* Lower privileges permanently */
1534
ret = setuid(uid);
1535
if(ret == -1){
1536
perror("setuid");
1537
}
1538
}
2969
bool interface_was_up = interface_is_up(interface);
2970
errno = bring_up_interface(interface, delay);
2971
if(not interface_was_up){
2972
if(errno != 0){
2973
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2974
" %s\n", interface, strerror(errno));
2975
} else {
2976
errno = argz_add(&interfaces_to_take_down,
2977
&interfaces_to_take_down_size,
2978
interface);
2979
if(errno != 0){
2980
perror_plus("argz_add");
2981
}
2982
}
2983
}
2984
}
2985
if(debug and (interfaces_to_take_down == NULL)){
2986
fprintf_plus(stderr, "No interfaces were brought up\n");
2987
}
2988
}
2989
2990
/* If we only got one interface, explicitly use only that one */
2991
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2992
if(debug){
2993
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2994
mc.interfaces);
2995
}
2996
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1539
2997
}
1540
2998
1541
2999
if(quit_now){
1542
3000
goto end;
1543
3001
}
1544
3002
1545
ret = init_gnutls_global(pubkey, seckey);
3003
#if GNUTLS_VERSION_NUMBER >= 0x030606
3004
ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);
3005
#elif GNUTLS_VERSION_NUMBER < 0x030600
3006
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
3007
#else
3008
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
3009
#endif
1546
3010
if(ret == -1){
1547
fprintf(stderr, "init_gnutls_global failed\n");
3011
fprintf_plus(stderr, "init_gnutls_global failed\n");
1548
3012
exitcode = EX_UNAVAILABLE;
1549
3013
goto end;
1550
3014
} else {
1555
3019
goto end;
1556
3020
}
1557
3021
1558
tempdir_created = true;
1559
if(mkdtemp(tempdir) == NULL){
1560
tempdir_created = false;
1561
perror("mkdtemp");
3022
/* Try /run/tmp before /tmp */
3023
tempdir = mkdtemp(run_tempdir);
3024
if(tempdir == NULL and errno == ENOENT){
3025
if(debug){
3026
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
3027
run_tempdir, old_tempdir);
3028
}
3029
tempdir = mkdtemp(old_tempdir);
3030
}
3031
if(tempdir == NULL){
3032
perror_plus("mkdtemp");
1562
3033
goto end;
1563
3034
}
1564
3035
1566
3037
goto end;
1567
3038
}
1568
3039
1569
if(not init_gpgme(pubkey, seckey, tempdir)){
1570
fprintf(stderr, "init_gpgme failed\n");
3040
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
3041
fprintf_plus(stderr, "init_gpgme failed\n");
1571
3042
exitcode = EX_UNAVAILABLE;
1572
3043
goto end;
1573
3044
} else {
1582
3053
/* Connect directly, do not use Zeroconf */
1583
3054
/* (Mainly meant for debugging) */
1584
3055
char *address = strrchr(connect_to, ':');
3056
1585
3057
if(address == NULL){
1586
fprintf(stderr, "No colon in address\n");
3058
fprintf_plus(stderr, "No colon in address\n");
1587
3059
exitcode = EX_USAGE;
1588
3060
goto end;
1589
3061
}
1592
3064
goto end;
1593
3065
}
1594
3066
1595
uint16_t port;
3067
in_port_t port;
1596
3068
errno = 0;
1597
3069
tmpmax = strtoimax(address+1, &tmp, 10);
1598
3070
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1599
or tmpmax != (uint16_t)tmpmax){
1600
fprintf(stderr, "Bad port number\n");
3071
or tmpmax != (in_port_t)tmpmax){
3072
fprintf_plus(stderr, "Bad port number\n");
1601
3073
exitcode = EX_USAGE;
1602
3074
goto end;
1603
3075
}
1604
3076
1605
3077
if(quit_now){
1606
3078
goto end;
1607
3079
}
1608
3080
1609
port = (uint16_t)tmpmax;
3081
port = (in_port_t)tmpmax;
1610
3082
*address = '\0';
1611
address = connect_to;
1612
3083
/* Colon in address indicates IPv6 */
1613
3084
int af;
1614
if(strchr(address, ':') != NULL){
3085
if(strchr(connect_to, ':') != NULL){
1615
3086
af = AF_INET6;
3087
/* Accept [] around IPv6 address - see RFC 5952 */
3088
if(connect_to[0] == '[' and address[-1] == ']')
3089
{
3090
connect_to++;
3091
address[-1] = '\0';
3092
}
1616
3093
} else {
1617
3094
af = AF_INET;
1618
3095
}
3096
address = connect_to;
1619
3097
1620
3098
if(quit_now){
1621
3099
goto end;
1622
3100
}
1623
3101
1624
3102
while(not quit_now){
1625
ret = start_mandos_communication(address, port, if_index, af);
3103
ret = start_mandos_communication(address, port, if_index, af,
3104
&mc);
1626
3105
if(quit_now or ret == 0){
1627
3106
break;
1628
3107
}
1629
sleep(15);
1630
};
1631
1632
if (not quit_now){
3108
if(debug){
3109
fprintf_plus(stderr, "Retrying in %d seconds\n",
3110
(int)retry_interval);
3111
}
3112
sleep((unsigned int)retry_interval);
3113
}
3114
3115
if(not quit_now){
1633
3116
exitcode = EXIT_SUCCESS;
1634
3117
}
1635
3118
1636
3119
goto end;
1637
3120
}
1638
3121
1650
3133
config.publish_domain = 0;
1651
3134
1652
3135
/* Allocate a new server */
1653
mc.server = avahi_server_new(avahi_simple_poll_get
1654
(mc.simple_poll), &config, NULL,
1655
NULL, &error);
3136
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
3137
&config, NULL, NULL, &ret);
1656
3138
1657
3139
/* Free the Avahi configuration data */
1658
3140
avahi_server_config_free(&config);
1660
3142
1661
3143
/* Check if creating the Avahi server object succeeded */
1662
3144
if(mc.server == NULL){
1663
fprintf(stderr, "Failed to create Avahi server: %s\n",
1664
avahi_strerror(error));
3145
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
3146
avahi_strerror(ret));
1665
3147
exitcode = EX_UNAVAILABLE;
1666
3148
goto end;
1667
3149
}
1673
3155
/* Create the Avahi service browser */
1674
3156
sb = avahi_s_service_browser_new(mc.server, if_index,
1675
3157
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1676
NULL, 0, browse_callback, NULL);
3158
NULL, 0, browse_callback,
3159
(void *)&mc);
1677
3160
if(sb == NULL){
1678
fprintf(stderr, "Failed to create service browser: %s\n",
1679
avahi_strerror(avahi_server_errno(mc.server)));
3161
fprintf_plus(stderr, "Failed to create service browser: %s\n",
3162
avahi_strerror(avahi_server_errno(mc.server)));
1680
3163
exitcode = EX_UNAVAILABLE;
1681
3164
goto end;
1682
3165
}
1688
3171
/* Run the main loop */
1689
3172
1690
3173
if(debug){
1691
fprintf(stderr, "Starting Avahi loop search\n");
3174
fprintf_plus(stderr, "Starting Avahi loop search\n");
1692
3175
}
1693
3176
1694
avahi_simple_poll_loop(mc.simple_poll);
3177
ret = avahi_loop_with_timeout(simple_poll,
3178
(int)(retry_interval * 1000), &mc);
3179
if(debug){
3180
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
3181
(ret == 0) ? "successfully" : "with error");
3182
}
1695
3183
1696
3184
end:
1697
3185
1698
3186
if(debug){
1699
fprintf(stderr, "%s exiting\n", argv[0]);
3187
if(signal_received){
3188
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
3189
argv[0], signal_received,
3190
strsignal(signal_received));
3191
} else {
3192
fprintf_plus(stderr, "%s exiting\n", argv[0]);
3193
}
1700
3194
}
1701
3195
1702
3196
/* Cleanup things */
3197
free(mc.interfaces);
3198
1703
3199
if(sb != NULL)
1704
3200
avahi_s_service_browser_free(sb);
1705
3201
1706
3202
if(mc.server != NULL)
1707
3203
avahi_server_free(mc.server);
1708
3204
1709
if(mc.simple_poll != NULL)
1710
avahi_simple_poll_free(mc.simple_poll);
3205
if(simple_poll != NULL)
3206
avahi_simple_poll_free(simple_poll);
1711
3207
1712
3208
if(gnutls_initialized){
1713
3209
gnutls_certificate_free_credentials(mc.cred);
1714
gnutls_global_deinit();
1715
3210
gnutls_dh_params_deinit(mc.dh_params);
1716
3211
}
1717
3212
1719
3214
gpgme_release(mc.ctx);
1720
3215
}
1721
3216
1722
/* Take down the network interface */
1723
if(take_down_interface){
1724
/* Re-raise priviliges */
1725
errno = 0;
1726
ret = seteuid(0);
1727
if(ret == -1){
1728
perror("seteuid");
1729
}
1730
if(geteuid() == 0){
1731
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1732
if(ret == -1){
1733
perror("ioctl SIOCGIFFLAGS");
1734
} else if(network.ifr_flags & IFF_UP) {
1735
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1736
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1737
if(ret == -1){
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1739
}
1740
}
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1742
if(ret == -1){
1743
perror("close");
1744
}
1745
/* Lower privileges permanently */
1746
errno = 0;
1747
ret = setuid(uid);
1748
if(ret == -1){
1749
perror("setuid");
1750
}
1751
}
1752
}
1753
1754
/* Removes the temp directory used by GPGME */
1755
if(tempdir_created){
1756
DIR *d;
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1759
if(d == NULL){
1760
if(errno != ENOENT){
1761
perror("opendir");
1762
}
1763
} else {
1764
while(true){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1767
break;
1768
}
1769
/* Skip "." and ".." */
1770
if(direntry->d_name[0] == '.'
1771
and (direntry->d_name[1] == '\0'
1772
or (direntry->d_name[1] == '.'
1773
and direntry->d_name[2] == '\0'))){
1774
continue;
1775
}
1776
char *fullname = NULL;
1777
ret = asprintf(&fullname, "%s/%s", tempdir,
1778
direntry->d_name);
1779
if(ret < 0){
1780
perror("asprintf");
1781
continue;
1782
}
1783
ret = remove(fullname);
1784
if(ret == -1){
1785
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1786
strerror(errno));
1787
}
1788
free(fullname);
1789
}
1790
closedir(d);
1791
}
1792
ret = rmdir(tempdir);
1793
if(ret == -1 and errno != ENOENT){
1794
perror("rmdir");
1795
}
3217
/* Cleans up the circular linked list of Mandos servers the client
3218
has seen */
3219
if(mc.current_server != NULL){
3220
mc.current_server->prev->next = NULL;
3221
while(mc.current_server != NULL){
3222
server *next = mc.current_server->next;
3223
#ifdef __GNUC__
3224
#pragma GCC diagnostic push
3225
#pragma GCC diagnostic ignored "-Wcast-qual"
3226
#endif
3227
free((char *)(mc.current_server->ip));
3228
#ifdef __GNUC__
3229
#pragma GCC diagnostic pop
3230
#endif
3231
free(mc.current_server);
3232
mc.current_server = next;
3233
}
3234
}
3235
3236
/* Re-raise privileges */
3237
{
3238
ret = raise_privileges();
3239
if(ret != 0){
3240
errno = ret;
3241
perror_plus("Failed to raise privileges");
3242
} else {
3243
3244
/* Run network hooks */
3245
run_network_hooks("stop", interfaces_hooks != NULL ?
3246
interfaces_hooks : "", delay);
3247
3248
/* Take down the network interfaces which were brought up */
3249
{
3250
char *interface = NULL;
3251
while((interface = argz_next(interfaces_to_take_down,
3252
interfaces_to_take_down_size,
3253
interface))){
3254
ret = take_down_interface(interface);
3255
if(ret != 0){
3256
errno = ret;
3257
perror_plus("Failed to take down interface");
3258
}
3259
}
3260
if(debug and (interfaces_to_take_down == NULL)){
3261
fprintf_plus(stderr, "No interfaces needed to be taken"
3262
" down\n");
3263
}
3264
}
3265
}
3266
3267
ret = lower_privileges_permanently();
3268
if(ret != 0){
3269
errno = ret;
3270
perror_plus("Failed to lower privileges permanently");
3271
}
3272
}
3273
3274
free(interfaces_to_take_down);
3275
free(interfaces_hooks);
3276
3277
void clean_dir_at(int base, const char * const dirname,
3278
uintmax_t level){
3279
struct dirent **direntries = NULL;
3280
int dret;
3281
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3282
O_RDONLY
3283
| O_NOFOLLOW
3284
| O_DIRECTORY
3285
| O_PATH));
3286
if(dir_fd == -1){
3287
perror_plus("open");
3288
return;
3289
}
3290
int numentries = scandirat(dir_fd, ".", &direntries,
3291
notdotentries, alphasort);
3292
if(numentries >= 0){
3293
for(int i = 0; i < numentries; i++){
3294
if(debug){
3295
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3296
dirname, direntries[i]->d_name);
3297
}
3298
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3299
if(dret == -1){
3300
if(errno == EISDIR){
3301
dret = unlinkat(dir_fd, direntries[i]->d_name,
3302
AT_REMOVEDIR);
3303
}
3304
if((dret == -1) and (errno == ENOTEMPTY)
3305
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3306
== 0) and (level == 0)){
3307
/* Recurse only in this special case */
3308
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3309
dret = 0;
3310
}
3311
if((dret == -1) and (errno != ENOENT)){
3312
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3313
direntries[i]->d_name, strerror(errno));
3314
}
3315
}
3316
free(direntries[i]);
3317
}
3318
3319
/* need to clean even if 0 because man page doesn't specify */
3320
free(direntries);
3321
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3322
if(dret == -1 and errno != ENOENT){
3323
perror_plus("rmdir");
3324
}
3325
} else {
3326
perror_plus("scandirat");
3327
}
3328
close(dir_fd);
3329
}
3330
3331
/* Removes the GPGME temp directory and all files inside */
3332
if(tempdir != NULL){
3333
clean_dir_at(-1, tempdir, 0);
1796
3334
}
1797
3335
1798
3336
if(quit_now){
1802
3340
&old_sigterm_action,
1803
3341
NULL));
1804
3342
if(ret == -1){
1805
perror("sigaction");
3343
perror_plus("sigaction");
1806
3344
}
1807
3345
do {
1808
3346
ret = raise(signal_received);
1809
3347
} while(ret != 0 and errno == EINTR);
1810
3348
if(ret != 0){
1811
perror("raise");
3349
perror_plus("raise");
1812
3350
abort();
1813
3351
}
1814
3352
TEMP_FAILURE_RETRY(pause());
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0