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- Committer: Teddy Hogeborn
- Date: 2016-03-17 20:40:55 UTC
- Revision ID: teddy@recompile.se-20160317204055-bhsh5xsidq7w5cxu
Client: Fix plymouth agent; broken since 1.7.2.
Fix an very old memory bug in the plymouth agent (which has been
present since its apperance in version 1.2), but which was only
recently detected at run time due to the new -fsanitize=address
compile- time flag, which has been used since version 1.7.2. This
detection of a memory access violation causes the program to abort,
making the Plymouth graphical boot system unable to accept interactive
input of passwords when using the Mandos client.
* plugins.d/plymouth.c (exec_and_wait): Fix memory allocation bug when
allocating new_argv. Also tolerate a zero-length argv.
Fix an very old memory bug in the plymouth agent (which has been
present since its apperance in version 1.2), but which was only
recently detected at run time due to the new -fsanitize=address
compile- time flag, which has been used since version 1.7.2. This
detection of a memory access violation causes the program to abort,
making the Plymouth graphical boot system unable to accept interactive
input of passwords when using the Mandos client.
* plugins.d/plymouth.c (exec_and_wait): Fix memory allocation bug when
allocating new_argv. Also tolerate a zero-length argv.
- files added:
- DBUS-API
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- files modified:
- .bzrignore
added
removed
plugins.d/mandos-client.c
9
9
* "browse_callback", and parts of "main".
10
10
*
11
11
* Everything else is
12
* Copyright © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
12
* Copyright © 2008-2016 Teddy Hogeborn
13
* Copyright © 2008-2016 Björn Påhlsson
14
14
*
15
15
* This program is free software: you can redistribute it and/or
16
16
* modify it under the terms of the GNU General Public License as
26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
28
28
*
29
* Contact the authors at <mandos@fukt.bsnet.se>.
29
* Contact the authors at <mandos@recompile.se>.
30
30
*/
31
31
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
33
34
#define _LARGEFILE_SOURCE
35
#endif /* not _LARGEFILE_SOURCE */
36
#ifndef _FILE_OFFSET_BITS
34
37
#define _FILE_OFFSET_BITS 64
38
#endif /* not _FILE_OFFSET_BITS */
35
39
36
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
37
41
38
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
40
remove() */
41
#include <stdint.h> /* uint16_t, uint32_t */
43
stdout, ferror() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
42
45
#include <stddef.h> /* NULL, size_t, ssize_t */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
44
srand() */
45
#include <stdbool.h> /* bool, true */
46
#include <string.h> /* memset(), strcmp(), strlen(),
47
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
strtof(), abort() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* strcmp(), strlen(), strerror(),
50
asprintf(), strncpy() */
51
#include <sys/ioctl.h> /* ioctl */
49
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
53
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
53
DIR */
54
#include <sys/stat.h> /* open() */
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
55
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
57
connect() */
58
#include <fcntl.h> /* open() */
58
inet_pton(), connect(),
59
getnameinfo() */
60
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
59
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
60
62
*/
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* time() */
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
strtoimax() */
65
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
66
EAI_SYSTEM, ENETUNREACH,
67
EHOSTUNREACH, ECONNREFUSED, EPROTO,
68
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
69
ENOTEMPTY,
70
program_invocation_short_name */
71
#include <time.h> /* nanosleep(), time(), sleep() */
65
72
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
73
SIOCSIFFLAGS, if_indextoname(),
67
74
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
75
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
76
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
77
*/
69
78
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
getuid(), getgid(), setuid(),
71
setgid() */
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
79
getuid(), getgid(), seteuid(),
80
setgid(), pause(), _exit(),
81
unlinkat() */
82
#include <arpa/inet.h> /* inet_pton(), htons() */
83
#include <iso646.h> /* not, or, and */
74
84
#include <argp.h> /* struct argp_option, error_t, struct
75
85
argp_state, struct argp,
76
86
argp_parse(), ARGP_KEY_ARG,
77
87
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
88
#include <signal.h> /* sigemptyset(), sigaddset(),
89
sigaction(), SIGTERM, sig_atomic_t,
90
raise() */
91
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
92
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
93
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
94
WEXITSTATUS(), WTERMSIG() */
95
#include <grp.h> /* setgroups() */
96
#include <argz.h> /* argz_add_sep(), argz_next(),
97
argz_delete(), argz_append(),
98
argz_stringify(), argz_add(),
99
argz_count() */
100
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
101
EAI_SYSTEM, gai_strerror() */
102
103
#ifdef __linux__
104
#include <sys/klog.h> /* klogctl() */
105
#endif /* __linux__ */
78
106
79
107
/* Avahi */
80
108
/* All Avahi types, constants and functions
94
122
init_gnutls_session(),
95
123
GNUTLS_* */
96
124
#include <gnutls/openpgp.h>
97
/* gnutls_certificate_set_openpgp_key_file(),
98
GNUTLS_OPENPGP_FMT_BASE64 */
125
/* gnutls_certificate_set_openpgp_key_file(),
126
GNUTLS_OPENPGP_FMT_BASE64 */
99
127
100
128
/* GPGME */
101
129
#include <gpgme.h> /* All GPGME types, constants and
109
137
#define PATHDIR "/conf/conf.d/mandos"
110
138
#define SECKEY "seckey.txt"
111
139
#define PUBKEY "pubkey.txt"
140
#define HOOKDIR "/lib/mandos/network-hooks.d"
112
141
113
142
bool debug = false;
114
143
static const char mandos_protocol_version[] = "1";
115
144
const char *argp_program_version = "mandos-client " VERSION;
116
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
145
const char *argp_program_bug_address = "<mandos@recompile.se>";
146
static const char sys_class_net[] = "/sys/class/net";
147
char *connect_to = NULL;
148
const char *hookdir = HOOKDIR;
149
int hookdir_fd = -1;
150
uid_t uid = 65534;
151
gid_t gid = 65534;
152
153
/* Doubly linked list that need to be circularly linked when used */
154
typedef struct server{
155
const char *ip;
156
in_port_t port;
157
AvahiIfIndex if_index;
158
int af;
159
struct timespec last_seen;
160
struct server *next;
161
struct server *prev;
162
} server;
117
163
118
164
/* Used for passing in values through the Avahi callback functions */
119
165
typedef struct {
120
AvahiSimplePoll *simple_poll;
121
166
AvahiServer *server;
122
167
gnutls_certificate_credentials_t cred;
123
168
unsigned int dh_bits;
124
169
gnutls_dh_params_t dh_params;
125
170
const char *priority;
126
171
gpgme_ctx_t ctx;
172
server *current_server;
173
char *interfaces;
174
size_t interfaces_size;
127
175
} mandos_context;
128
176
177
/* global so signal handler can reach it*/
178
AvahiSimplePoll *simple_poll;
179
180
sig_atomic_t quit_now = 0;
181
int signal_received = 0;
182
183
/* Function to use when printing errors */
184
void perror_plus(const char *print_text){
185
int e = errno;
186
fprintf(stderr, "Mandos plugin %s: ",
187
program_invocation_short_name);
188
errno = e;
189
perror(print_text);
190
}
191
192
__attribute__((format (gnu_printf, 2, 3), nonnull))
193
int fprintf_plus(FILE *stream, const char *format, ...){
194
va_list ap;
195
va_start (ap, format);
196
197
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
198
program_invocation_short_name));
199
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
200
}
201
129
202
/*
130
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
131
* "buffer_capacity" is how much is currently allocated,
203
* Make additional room in "buffer" for at least BUFFER_SIZE more
204
* bytes. "buffer_capacity" is how much is currently allocated,
132
205
* "buffer_length" is how much is already used.
133
206
*/
134
size_t adjustbuffer(char **buffer, size_t buffer_length,
135
size_t buffer_capacity){
207
__attribute__((nonnull, warn_unused_result))
208
size_t incbuffer(char **buffer, size_t buffer_length,
209
size_t buffer_capacity){
136
210
if(buffer_length + BUFFER_SIZE > buffer_capacity){
137
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
138
if(buffer == NULL){
211
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
212
if(new_buf == NULL){
213
int old_errno = errno;
214
free(*buffer);
215
errno = old_errno;
216
*buffer = NULL;
139
217
return 0;
140
218
}
219
*buffer = new_buf;
141
220
buffer_capacity += BUFFER_SIZE;
142
221
}
143
222
return buffer_capacity;
144
223
}
145
224
225
/* Add server to set of servers to retry periodically */
226
__attribute__((nonnull, warn_unused_result))
227
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
228
int af, server **current_server){
229
int ret;
230
server *new_server = malloc(sizeof(server));
231
if(new_server == NULL){
232
perror_plus("malloc");
233
return false;
234
}
235
*new_server = (server){ .ip = strdup(ip),
236
.port = port,
237
.if_index = if_index,
238
.af = af };
239
if(new_server->ip == NULL){
240
perror_plus("strdup");
241
free(new_server);
242
return false;
243
}
244
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
245
if(ret == -1){
246
perror_plus("clock_gettime");
247
#ifdef __GNUC__
248
#pragma GCC diagnostic push
249
#pragma GCC diagnostic ignored "-Wcast-qual"
250
#endif
251
free((char *)(new_server->ip));
252
#ifdef __GNUC__
253
#pragma GCC diagnostic pop
254
#endif
255
free(new_server);
256
return false;
257
}
258
/* Special case of first server */
259
if(*current_server == NULL){
260
new_server->next = new_server;
261
new_server->prev = new_server;
262
*current_server = new_server;
263
} else {
264
/* Place the new server last in the list */
265
new_server->next = *current_server;
266
new_server->prev = (*current_server)->prev;
267
new_server->prev->next = new_server;
268
(*current_server)->prev = new_server;
269
}
270
return true;
271
}
272
146
273
/*
147
274
* Initialize GPGME.
148
275
*/
149
static bool init_gpgme(mandos_context *mc, const char *seckey,
150
const char *pubkey, const char *tempdir){
151
int ret;
276
__attribute__((nonnull, warn_unused_result))
277
static bool init_gpgme(const char * const seckey,
278
const char * const pubkey,
279
const char * const tempdir,
280
mandos_context *mc){
152
281
gpgme_error_t rc;
153
282
gpgme_engine_info_t engine_info;
154
283
155
156
284
/*
157
285
* Helper function to insert pub and seckey to the engine keyring.
158
286
*/
159
bool import_key(const char *filename){
287
bool import_key(const char * const filename){
288
int ret;
160
289
int fd;
161
290
gpgme_data_t pgp_data;
162
291
163
292
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
164
293
if(fd == -1){
165
perror("open");
294
perror_plus("open");
166
295
return false;
167
296
}
168
297
169
298
rc = gpgme_data_new_from_fd(&pgp_data, fd);
170
299
if(rc != GPG_ERR_NO_ERROR){
171
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
172
gpgme_strsource(rc), gpgme_strerror(rc));
300
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
301
gpgme_strsource(rc), gpgme_strerror(rc));
173
302
return false;
174
303
}
175
304
176
305
rc = gpgme_op_import(mc->ctx, pgp_data);
177
306
if(rc != GPG_ERR_NO_ERROR){
178
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
179
gpgme_strsource(rc), gpgme_strerror(rc));
307
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
180
309
return false;
181
310
}
182
311
183
ret = (int)TEMP_FAILURE_RETRY(close(fd));
312
ret = close(fd);
184
313
if(ret == -1){
185
perror("close");
314
perror_plus("close");
186
315
}
187
316
gpgme_data_release(pgp_data);
188
317
return true;
189
318
}
190
319
191
320
if(debug){
192
fprintf(stderr, "Initialize gpgme\n");
321
fprintf_plus(stderr, "Initializing GPGME\n");
193
322
}
194
323
195
324
/* Init GPGME */
196
325
gpgme_check_version(NULL);
197
326
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
198
327
if(rc != GPG_ERR_NO_ERROR){
199
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
200
gpgme_strsource(rc), gpgme_strerror(rc));
328
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
329
gpgme_strsource(rc), gpgme_strerror(rc));
201
330
return false;
202
331
}
203
332
204
/* Set GPGME home directory for the OpenPGP engine only */
333
/* Set GPGME home directory for the OpenPGP engine only */
205
334
rc = gpgme_get_engine_info(&engine_info);
206
335
if(rc != GPG_ERR_NO_ERROR){
207
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
208
gpgme_strsource(rc), gpgme_strerror(rc));
336
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
337
gpgme_strsource(rc), gpgme_strerror(rc));
209
338
return false;
210
339
}
211
340
while(engine_info != NULL){
217
346
engine_info = engine_info->next;
218
347
}
219
348
if(engine_info == NULL){
220
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
349
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
350
tempdir);
221
351
return false;
222
352
}
223
353
224
354
/* Create new GPGME "context" */
225
355
rc = gpgme_new(&(mc->ctx));
226
356
if(rc != GPG_ERR_NO_ERROR){
227
fprintf(stderr, "bad gpgme_new: %s: %s\n",
228
gpgme_strsource(rc), gpgme_strerror(rc));
357
fprintf_plus(stderr, "Mandos plugin mandos-client: "
358
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
359
gpgme_strerror(rc));
229
360
return false;
230
361
}
231
362
233
364
return false;
234
365
}
235
366
236
return true;
367
return true;
237
368
}
238
369
239
370
/*
240
371
* Decrypt OpenPGP data.
241
372
* Returns -1 on error
242
373
*/
243
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
244
const char *cryptotext,
374
__attribute__((nonnull, warn_unused_result))
375
static ssize_t pgp_packet_decrypt(const char *cryptotext,
245
376
size_t crypto_size,
246
char **plaintext){
377
char **plaintext,
378
mandos_context *mc){
247
379
gpgme_data_t dh_crypto, dh_plain;
248
380
gpgme_error_t rc;
249
381
ssize_t ret;
251
383
ssize_t plaintext_length = 0;
252
384
253
385
if(debug){
254
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
386
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
255
387
}
256
388
257
389
/* Create new GPGME data buffer from memory cryptotext */
258
390
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
259
391
0);
260
392
if(rc != GPG_ERR_NO_ERROR){
261
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
262
gpgme_strsource(rc), gpgme_strerror(rc));
393
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
394
gpgme_strsource(rc), gpgme_strerror(rc));
263
395
return -1;
264
396
}
265
397
266
398
/* Create new empty GPGME data buffer for the plaintext */
267
399
rc = gpgme_data_new(&dh_plain);
268
400
if(rc != GPG_ERR_NO_ERROR){
269
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
270
gpgme_strsource(rc), gpgme_strerror(rc));
401
fprintf_plus(stderr, "Mandos plugin mandos-client: "
402
"bad gpgme_data_new: %s: %s\n",
403
gpgme_strsource(rc), gpgme_strerror(rc));
271
404
gpgme_data_release(dh_crypto);
272
405
return -1;
273
406
}
276
409
data buffer */
277
410
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
278
411
if(rc != GPG_ERR_NO_ERROR){
279
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
280
gpgme_strsource(rc), gpgme_strerror(rc));
412
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
281
414
plaintext_length = -1;
282
415
if(debug){
283
416
gpgme_decrypt_result_t result;
284
417
result = gpgme_op_decrypt_result(mc->ctx);
285
418
if(result == NULL){
286
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
419
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
287
420
} else {
288
fprintf(stderr, "Unsupported algorithm: %s\n",
289
result->unsupported_algorithm);
290
fprintf(stderr, "Wrong key usage: %u\n",
291
result->wrong_key_usage);
421
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
422
result->unsupported_algorithm);
423
fprintf_plus(stderr, "Wrong key usage: %u\n",
424
result->wrong_key_usage);
292
425
if(result->file_name != NULL){
293
fprintf(stderr, "File name: %s\n", result->file_name);
426
fprintf_plus(stderr, "File name: %s\n", result->file_name);
294
427
}
295
428
gpgme_recipient_t recipient;
296
429
recipient = result->recipients;
297
if(recipient){
298
while(recipient != NULL){
299
fprintf(stderr, "Public key algorithm: %s\n",
300
gpgme_pubkey_algo_name(recipient->pubkey_algo));
301
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
302
fprintf(stderr, "Secret key available: %s\n",
303
recipient->status == GPG_ERR_NO_SECKEY
304
? "No" : "Yes");
305
recipient = recipient->next;
306
}
430
while(recipient != NULL){
431
fprintf_plus(stderr, "Public key algorithm: %s\n",
432
gpgme_pubkey_algo_name
433
(recipient->pubkey_algo));
434
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
435
fprintf_plus(stderr, "Secret key available: %s\n",
436
recipient->status == GPG_ERR_NO_SECKEY
437
? "No" : "Yes");
438
recipient = recipient->next;
307
439
}
308
440
}
309
441
}
311
443
}
312
444
313
445
if(debug){
314
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
446
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
315
447
}
316
448
317
449
/* Seek back to the beginning of the GPGME plaintext data buffer */
318
450
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
319
perror("gpgme_data_seek");
451
perror_plus("gpgme_data_seek");
320
452
plaintext_length = -1;
321
453
goto decrypt_end;
322
454
}
323
455
324
456
*plaintext = NULL;
325
457
while(true){
326
plaintext_capacity = adjustbuffer(plaintext,
327
(size_t)plaintext_length,
328
plaintext_capacity);
458
plaintext_capacity = incbuffer(plaintext,
459
(size_t)plaintext_length,
460
plaintext_capacity);
329
461
if(plaintext_capacity == 0){
330
perror("adjustbuffer");
331
plaintext_length = -1;
332
goto decrypt_end;
462
perror_plus("incbuffer");
463
plaintext_length = -1;
464
goto decrypt_end;
333
465
}
334
466
335
467
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
340
472
break;
341
473
}
342
474
if(ret < 0){
343
perror("gpgme_data_read");
475
perror_plus("gpgme_data_read");
344
476
plaintext_length = -1;
345
477
goto decrypt_end;
346
478
}
348
480
}
349
481
350
482
if(debug){
351
fprintf(stderr, "Decrypted password is: ");
483
fprintf_plus(stderr, "Decrypted password is: ");
352
484
for(ssize_t i = 0; i < plaintext_length; i++){
353
485
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
354
486
}
365
497
return plaintext_length;
366
498
}
367
499
368
static const char * safer_gnutls_strerror(int value) {
369
const char *ret = gnutls_strerror(value); /* Spurious warning from
370
-Wunreachable-code */
371
if(ret == NULL)
372
ret = "(unknown)";
373
return ret;
500
__attribute__((warn_unused_result, const))
501
static const char *safe_string(const char *str){
502
if(str == NULL)
503
return "(unknown)";
504
return str;
505
}
506
507
__attribute__((warn_unused_result))
508
static const char *safer_gnutls_strerror(int value){
509
const char *ret = gnutls_strerror(value);
510
return safe_string(ret);
374
511
}
375
512
376
513
/* GnuTLS log function callback */
514
__attribute__((nonnull))
377
515
static void debuggnutls(__attribute__((unused)) int level,
378
516
const char* string){
379
fprintf(stderr, "GnuTLS: %s", string);
517
fprintf_plus(stderr, "GnuTLS: %s", string);
380
518
}
381
519
382
static int init_gnutls_global(mandos_context *mc,
383
const char *pubkeyfilename,
384
const char *seckeyfilename){
520
__attribute__((nonnull(1, 2, 4), warn_unused_result))
521
static int init_gnutls_global(const char *pubkeyfilename,
522
const char *seckeyfilename,
523
const char *dhparamsfilename,
524
mandos_context *mc){
385
525
int ret;
526
unsigned int uret;
386
527
387
528
if(debug){
388
fprintf(stderr, "Initializing GnuTLS\n");
389
}
390
391
ret = gnutls_global_init();
392
if(ret != GNUTLS_E_SUCCESS) {
393
fprintf(stderr, "GnuTLS global_init: %s\n",
394
safer_gnutls_strerror(ret));
395
return -1;
529
fprintf_plus(stderr, "Initializing GnuTLS\n");
396
530
}
397
531
398
532
if(debug){
404
538
}
405
539
406
540
/* OpenPGP credentials */
407
gnutls_certificate_allocate_credentials(&mc->cred);
541
ret = gnutls_certificate_allocate_credentials(&mc->cred);
408
542
if(ret != GNUTLS_E_SUCCESS){
409
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
410
* from
411
* -Wunreachable-code
412
*/
413
safer_gnutls_strerror(ret));
414
gnutls_global_deinit();
543
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
544
safer_gnutls_strerror(ret));
415
545
return -1;
416
546
}
417
547
418
548
if(debug){
419
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
420
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
421
seckeyfilename);
549
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
550
" secret key %s as GnuTLS credentials\n",
551
pubkeyfilename,
552
seckeyfilename);
422
553
}
423
554
424
555
ret = gnutls_certificate_set_openpgp_key_file
425
556
(mc->cred, pubkeyfilename, seckeyfilename,
426
557
GNUTLS_OPENPGP_FMT_BASE64);
427
if(ret != GNUTLS_E_SUCCESS) {
428
fprintf(stderr,
429
"Error[%d] while reading the OpenPGP key pair ('%s',"
430
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
431
fprintf(stderr, "The GnuTLS error is: %s\n",
432
safer_gnutls_strerror(ret));
558
if(ret != GNUTLS_E_SUCCESS){
559
fprintf_plus(stderr,
560
"Error[%d] while reading the OpenPGP key pair ('%s',"
561
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
562
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
563
safer_gnutls_strerror(ret));
433
564
goto globalfail;
434
565
}
435
566
436
567
/* GnuTLS server initialization */
437
568
ret = gnutls_dh_params_init(&mc->dh_params);
438
if(ret != GNUTLS_E_SUCCESS) {
439
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
440
" %s\n", safer_gnutls_strerror(ret));
441
goto globalfail;
442
}
443
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
444
if(ret != GNUTLS_E_SUCCESS) {
445
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
446
safer_gnutls_strerror(ret));
447
goto globalfail;
448
}
449
569
if(ret != GNUTLS_E_SUCCESS){
570
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
571
" initialization: %s\n",
572
safer_gnutls_strerror(ret));
573
goto globalfail;
574
}
575
/* If a Diffie-Hellman parameters file was given, try to use it */
576
if(dhparamsfilename != NULL){
577
gnutls_datum_t params = { .data = NULL, .size = 0 };
578
do {
579
int dhpfile = open(dhparamsfilename, O_RDONLY);
580
if(dhpfile == -1){
581
perror_plus("open");
582
dhparamsfilename = NULL;
583
break;
584
}
585
size_t params_capacity = 0;
586
while(true){
587
params_capacity = incbuffer((char **)¶ms.data,
588
(size_t)params.size,
589
(size_t)params_capacity);
590
if(params_capacity == 0){
591
perror_plus("incbuffer");
592
free(params.data);
593
params.data = NULL;
594
dhparamsfilename = NULL;
595
break;
596
}
597
ssize_t bytes_read = read(dhpfile,
598
params.data + params.size,
599
BUFFER_SIZE);
600
/* EOF */
601
if(bytes_read == 0){
602
break;
603
}
604
/* check bytes_read for failure */
605
if(bytes_read < 0){
606
perror_plus("read");
607
free(params.data);
608
params.data = NULL;
609
dhparamsfilename = NULL;
610
break;
611
}
612
params.size += (unsigned int)bytes_read;
613
}
614
if(params.data == NULL){
615
dhparamsfilename = NULL;
616
}
617
if(dhparamsfilename == NULL){
618
break;
619
}
620
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
621
GNUTLS_X509_FMT_PEM);
622
if(ret != GNUTLS_E_SUCCESS){
623
fprintf_plus(stderr, "Failed to parse DH parameters in file"
624
" \"%s\": %s\n", dhparamsfilename,
625
safer_gnutls_strerror(ret));
626
dhparamsfilename = NULL;
627
}
628
} while(false);
629
}
630
if(dhparamsfilename == NULL){
631
if(mc->dh_bits == 0){
632
/* Find out the optimal number of DH bits */
633
/* Try to read the private key file */
634
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
635
do {
636
int secfile = open(seckeyfilename, O_RDONLY);
637
if(secfile == -1){
638
perror_plus("open");
639
break;
640
}
641
size_t buffer_capacity = 0;
642
while(true){
643
buffer_capacity = incbuffer((char **)&buffer.data,
644
(size_t)buffer.size,
645
(size_t)buffer_capacity);
646
if(buffer_capacity == 0){
647
perror_plus("incbuffer");
648
free(buffer.data);
649
buffer.data = NULL;
650
break;
651
}
652
ssize_t bytes_read = read(secfile,
653
buffer.data + buffer.size,
654
BUFFER_SIZE);
655
/* EOF */
656
if(bytes_read == 0){
657
break;
658
}
659
/* check bytes_read for failure */
660
if(bytes_read < 0){
661
perror_plus("read");
662
free(buffer.data);
663
buffer.data = NULL;
664
break;
665
}
666
buffer.size += (unsigned int)bytes_read;
667
}
668
close(secfile);
669
} while(false);
670
/* If successful, use buffer to parse private key */
671
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
672
if(buffer.data != NULL){
673
{
674
gnutls_openpgp_privkey_t privkey = NULL;
675
ret = gnutls_openpgp_privkey_init(&privkey);
676
if(ret != GNUTLS_E_SUCCESS){
677
fprintf_plus(stderr, "Error initializing OpenPGP key"
678
" structure: %s",
679
safer_gnutls_strerror(ret));
680
free(buffer.data);
681
buffer.data = NULL;
682
} else {
683
ret = gnutls_openpgp_privkey_import
684
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
685
if(ret != GNUTLS_E_SUCCESS){
686
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
687
safer_gnutls_strerror(ret));
688
privkey = NULL;
689
}
690
free(buffer.data);
691
buffer.data = NULL;
692
if(privkey != NULL){
693
/* Use private key to suggest an appropriate
694
sec_param */
695
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
696
gnutls_openpgp_privkey_deinit(privkey);
697
if(debug){
698
fprintf_plus(stderr, "This OpenPGP key implies using"
699
" a GnuTLS security parameter \"%s\".\n",
700
safe_string(gnutls_sec_param_get_name
701
(sec_param)));
702
}
703
}
704
}
705
}
706
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
707
/* Err on the side of caution */
708
sec_param = GNUTLS_SEC_PARAM_ULTRA;
709
if(debug){
710
fprintf_plus(stderr, "Falling back to security parameter"
711
" \"%s\"\n",
712
safe_string(gnutls_sec_param_get_name
713
(sec_param)));
714
}
715
}
716
}
717
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
718
if(uret != 0){
719
mc->dh_bits = uret;
720
if(debug){
721
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
722
" implies %u DH bits; using that.\n",
723
safe_string(gnutls_sec_param_get_name
724
(sec_param)),
725
mc->dh_bits);
726
}
727
} else {
728
fprintf_plus(stderr, "Failed to get implied number of DH"
729
" bits for security parameter \"%s\"): %s\n",
730
safe_string(gnutls_sec_param_get_name
731
(sec_param)),
732
safer_gnutls_strerror(ret));
733
goto globalfail;
734
}
735
} else if(debug){
736
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
737
mc->dh_bits);
738
}
739
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
740
if(ret != GNUTLS_E_SUCCESS){
741
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
742
" bits): %s\n", mc->dh_bits,
743
safer_gnutls_strerror(ret));
744
goto globalfail;
745
}
746
}
450
747
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
451
748
452
749
return 0;
454
751
globalfail:
455
752
456
753
gnutls_certificate_free_credentials(mc->cred);
457
gnutls_global_deinit();
458
754
gnutls_dh_params_deinit(mc->dh_params);
459
755
return -1;
460
756
}
461
757
462
static int init_gnutls_session(mandos_context *mc,
463
gnutls_session_t *session){
758
__attribute__((nonnull, warn_unused_result))
759
static int init_gnutls_session(gnutls_session_t *session,
760
mandos_context *mc){
464
761
int ret;
465
762
/* GnuTLS session creation */
466
ret = gnutls_init(session, GNUTLS_SERVER);
763
do {
764
ret = gnutls_init(session, GNUTLS_SERVER);
765
if(quit_now){
766
return -1;
767
}
768
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
467
769
if(ret != GNUTLS_E_SUCCESS){
468
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
469
safer_gnutls_strerror(ret));
770
fprintf_plus(stderr,
771
"Error in GnuTLS session initialization: %s\n",
772
safer_gnutls_strerror(ret));
470
773
}
471
774
472
775
{
473
776
const char *err;
474
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
475
if(ret != GNUTLS_E_SUCCESS) {
476
fprintf(stderr, "Syntax error at: %s\n", err);
477
fprintf(stderr, "GnuTLS error: %s\n",
478
safer_gnutls_strerror(ret));
777
do {
778
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
779
if(quit_now){
780
gnutls_deinit(*session);
781
return -1;
782
}
783
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
784
if(ret != GNUTLS_E_SUCCESS){
785
fprintf_plus(stderr, "Syntax error at: %s\n", err);
786
fprintf_plus(stderr, "GnuTLS error: %s\n",
787
safer_gnutls_strerror(ret));
479
788
gnutls_deinit(*session);
480
789
return -1;
481
790
}
482
791
}
483
792
484
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
485
mc->cred);
486
if(ret != GNUTLS_E_SUCCESS) {
487
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
488
safer_gnutls_strerror(ret));
793
do {
794
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
795
mc->cred);
796
if(quit_now){
797
gnutls_deinit(*session);
798
return -1;
799
}
800
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
801
if(ret != GNUTLS_E_SUCCESS){
802
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
803
safer_gnutls_strerror(ret));
489
804
gnutls_deinit(*session);
490
805
return -1;
491
806
}
492
807
493
808
/* ignore client certificate if any. */
494
gnutls_certificate_server_set_request(*session,
495
GNUTLS_CERT_IGNORE);
496
497
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
809
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
498
810
499
811
return 0;
500
812
}
503
815
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
504
816
__attribute__((unused)) const char *txt){}
505
817
818
/* Set effective uid to 0, return errno */
819
__attribute__((warn_unused_result))
820
int raise_privileges(void){
821
int old_errno = errno;
822
int ret = 0;
823
if(seteuid(0) == -1){
824
ret = errno;
825
}
826
errno = old_errno;
827
return ret;
828
}
829
830
/* Set effective and real user ID to 0. Return errno. */
831
__attribute__((warn_unused_result))
832
int raise_privileges_permanently(void){
833
int old_errno = errno;
834
int ret = raise_privileges();
835
if(ret != 0){
836
errno = old_errno;
837
return ret;
838
}
839
if(setuid(0) == -1){
840
ret = errno;
841
}
842
errno = old_errno;
843
return ret;
844
}
845
846
/* Set effective user ID to unprivileged saved user ID */
847
__attribute__((warn_unused_result))
848
int lower_privileges(void){
849
int old_errno = errno;
850
int ret = 0;
851
if(seteuid(uid) == -1){
852
ret = errno;
853
}
854
errno = old_errno;
855
return ret;
856
}
857
858
/* Lower privileges permanently */
859
__attribute__((warn_unused_result))
860
int lower_privileges_permanently(void){
861
int old_errno = errno;
862
int ret = 0;
863
if(setuid(uid) == -1){
864
ret = errno;
865
}
866
errno = old_errno;
867
return ret;
868
}
869
870
/* Helper function to add_local_route() and delete_local_route() */
871
__attribute__((nonnull, warn_unused_result))
872
static bool add_delete_local_route(const bool add,
873
const char *address,
874
AvahiIfIndex if_index){
875
int ret;
876
char helper[] = "mandos-client-iprouteadddel";
877
char add_arg[] = "add";
878
char delete_arg[] = "delete";
879
char debug_flag[] = "--debug";
880
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
881
if(pluginhelperdir == NULL){
882
if(debug){
883
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
884
" variable not set; cannot run helper\n");
885
}
886
return false;
887
}
888
889
char interface[IF_NAMESIZE];
890
if(if_indextoname((unsigned int)if_index, interface) == NULL){
891
perror_plus("if_indextoname");
892
return false;
893
}
894
895
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
896
if(devnull == -1){
897
perror_plus("open(\"/dev/null\", O_RDONLY)");
898
return false;
899
}
900
pid_t pid = fork();
901
if(pid == 0){
902
/* Child */
903
/* Raise privileges */
904
errno = raise_privileges_permanently();
905
if(errno != 0){
906
perror_plus("Failed to raise privileges");
907
/* _exit(EX_NOPERM); */
908
} else {
909
/* Set group */
910
errno = 0;
911
ret = setgid(0);
912
if(ret == -1){
913
perror_plus("setgid");
914
_exit(EX_NOPERM);
915
}
916
/* Reset supplementary groups */
917
errno = 0;
918
ret = setgroups(0, NULL);
919
if(ret == -1){
920
perror_plus("setgroups");
921
_exit(EX_NOPERM);
922
}
923
}
924
ret = dup2(devnull, STDIN_FILENO);
925
if(ret == -1){
926
perror_plus("dup2(devnull, STDIN_FILENO)");
927
_exit(EX_OSERR);
928
}
929
ret = close(devnull);
930
if(ret == -1){
931
perror_plus("close");
932
_exit(EX_OSERR);
933
}
934
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
935
if(ret == -1){
936
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
937
_exit(EX_OSERR);
938
}
939
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
940
O_RDONLY
941
| O_DIRECTORY
942
| O_PATH
943
| O_CLOEXEC));
944
if(helperdir_fd == -1){
945
perror_plus("open");
946
_exit(EX_UNAVAILABLE);
947
}
948
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
949
helper, O_RDONLY));
950
if(helper_fd == -1){
951
perror_plus("openat");
952
close(helperdir_fd);
953
_exit(EX_UNAVAILABLE);
954
}
955
close(helperdir_fd);
956
#ifdef __GNUC__
957
#pragma GCC diagnostic push
958
#pragma GCC diagnostic ignored "-Wcast-qual"
959
#endif
960
if(fexecve(helper_fd, (char *const [])
961
{ helper, add ? add_arg : delete_arg, (char *)address,
962
interface, debug ? debug_flag : NULL, NULL },
963
environ) == -1){
964
#ifdef __GNUC__
965
#pragma GCC diagnostic pop
966
#endif
967
perror_plus("fexecve");
968
_exit(EXIT_FAILURE);
969
}
970
}
971
if(pid == -1){
972
perror_plus("fork");
973
return false;
974
}
975
int status;
976
pid_t pret = -1;
977
errno = 0;
978
do {
979
pret = waitpid(pid, &status, 0);
980
if(pret == -1 and errno == EINTR and quit_now){
981
int errno_raising = 0;
982
if((errno = raise_privileges()) != 0){
983
errno_raising = errno;
984
perror_plus("Failed to raise privileges in order to"
985
" kill helper program");
986
}
987
if(kill(pid, SIGTERM) == -1){
988
perror_plus("kill");
989
}
990
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
991
perror_plus("Failed to lower privileges after killing"
992
" helper program");
993
}
994
return false;
995
}
996
} while(pret == -1 and errno == EINTR);
997
if(pret == -1){
998
perror_plus("waitpid");
999
return false;
1000
}
1001
if(WIFEXITED(status)){
1002
if(WEXITSTATUS(status) != 0){
1003
fprintf_plus(stderr, "Error: iprouteadddel exited"
1004
" with status %d\n", WEXITSTATUS(status));
1005
return false;
1006
}
1007
return true;
1008
}
1009
if(WIFSIGNALED(status)){
1010
fprintf_plus(stderr, "Error: iprouteadddel died by"
1011
" signal %d\n", WTERMSIG(status));
1012
return false;
1013
}
1014
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1015
return false;
1016
}
1017
1018
__attribute__((nonnull, warn_unused_result))
1019
static bool add_local_route(const char *address,
1020
AvahiIfIndex if_index){
1021
if(debug){
1022
fprintf_plus(stderr, "Adding route to %s\n", address);
1023
}
1024
return add_delete_local_route(true, address, if_index);
1025
}
1026
1027
__attribute__((nonnull, warn_unused_result))
1028
static bool delete_local_route(const char *address,
1029
AvahiIfIndex if_index){
1030
if(debug){
1031
fprintf_plus(stderr, "Removing route to %s\n", address);
1032
}
1033
return add_delete_local_route(false, address, if_index);
1034
}
1035
506
1036
/* Called when a Mandos server is found */
507
static int start_mandos_communication(const char *ip, uint16_t port,
1037
__attribute__((nonnull, warn_unused_result))
1038
static int start_mandos_communication(const char *ip, in_port_t port,
508
1039
AvahiIfIndex if_index,
509
mandos_context *mc){
510
int ret, tcp_sd;
1040
int af, mandos_context *mc){
1041
int ret, tcp_sd = -1;
511
1042
ssize_t sret;
512
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1043
struct sockaddr_storage to;
513
1044
char *buffer = NULL;
514
char *decrypted_buffer;
1045
char *decrypted_buffer = NULL;
515
1046
size_t buffer_length = 0;
516
1047
size_t buffer_capacity = 0;
517
ssize_t decrypted_buffer_size;
518
1048
size_t written;
519
int retval = 0;
520
char interface[IF_NAMESIZE];
1049
int retval = -1;
521
1050
gnutls_session_t session;
522
523
ret = init_gnutls_session(mc, &session);
1051
int pf; /* Protocol family */
1052
bool route_added = false;
1053
1054
errno = 0;
1055
1056
if(quit_now){
1057
errno = EINTR;
1058
return -1;
1059
}
1060
1061
switch(af){
1062
case AF_INET6:
1063
pf = PF_INET6;
1064
break;
1065
case AF_INET:
1066
pf = PF_INET;
1067
break;
1068
default:
1069
fprintf_plus(stderr, "Bad address family: %d\n", af);
1070
errno = EINVAL;
1071
return -1;
1072
}
1073
1074
/* If the interface is specified and we have a list of interfaces */
1075
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1076
/* Check if the interface is one of the interfaces we are using */
1077
bool match = false;
1078
{
1079
char *interface = NULL;
1080
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1081
interface))){
1082
if(if_nametoindex(interface) == (unsigned int)if_index){
1083
match = true;
1084
break;
1085
}
1086
}
1087
}
1088
if(not match){
1089
/* This interface does not match any in the list, so we don't
1090
connect to the server */
1091
if(debug){
1092
char interface[IF_NAMESIZE];
1093
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1094
perror_plus("if_indextoname");
1095
} else {
1096
fprintf_plus(stderr, "Skipping server on non-used interface"
1097
" \"%s\"\n",
1098
if_indextoname((unsigned int)if_index,
1099
interface));
1100
}
1101
}
1102
return -1;
1103
}
1104
}
1105
1106
ret = init_gnutls_session(&session, mc);
524
1107
if(ret != 0){
525
1108
return -1;
526
1109
}
527
1110
528
1111
if(debug){
529
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
530
"\n", ip, port);
531
}
532
533
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
534
if(tcp_sd < 0) {
535
perror("socket");
536
return -1;
537
}
538
539
if(debug){
540
if(if_indextoname((unsigned int)if_index, interface) == NULL){
541
perror("if_indextoname");
542
return -1;
543
}
544
fprintf(stderr, "Binding to interface %s\n", interface);
545
}
546
547
memset(&to, 0, sizeof(to));
548
to.in6.sin6_family = AF_INET6;
549
/* It would be nice to have a way to detect if we were passed an
550
IPv4 address here. Now we assume an IPv6 address. */
551
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
1112
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1113
PRIuMAX "\n", ip, (uintmax_t)port);
1114
}
1115
1116
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1117
if(tcp_sd < 0){
1118
int e = errno;
1119
perror_plus("socket");
1120
errno = e;
1121
goto mandos_end;
1122
}
1123
1124
if(quit_now){
1125
errno = EINTR;
1126
goto mandos_end;
1127
}
1128
1129
if(af == AF_INET6){
1130
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1131
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1132
ret = inet_pton(af, ip, &to6->sin6_addr);
1133
} else { /* IPv4 */
1134
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1135
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to4->sin_addr);
1137
}
552
1138
if(ret < 0 ){
553
perror("inet_pton");
554
return -1;
1139
int e = errno;
1140
perror_plus("inet_pton");
1141
errno = e;
1142
goto mandos_end;
555
1143
}
556
1144
if(ret == 0){
557
fprintf(stderr, "Bad address: %s\n", ip);
558
return -1;
559
}
560
to.in6.sin6_port = htons(port); /* Spurious warnings from
561
-Wconversion and
562
-Wunreachable-code */
1145
int e = errno;
1146
fprintf_plus(stderr, "Bad address: %s\n", ip);
1147
errno = e;
1148
goto mandos_end;
1149
}
1150
if(af == AF_INET6){
1151
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1152
if(IN6_IS_ADDR_LINKLOCAL
1153
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1154
if(if_index == AVAHI_IF_UNSPEC){
1155
fprintf_plus(stderr, "An IPv6 link-local address is"
1156
" incomplete without a network interface\n");
1157
errno = EINVAL;
1158
goto mandos_end;
1159
}
1160
/* Set the network interface number as scope */
1161
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1162
}
1163
} else {
1164
((struct sockaddr_in *)&to)->sin_port = htons(port);
1165
}
563
1166
564
to.in6.sin6_scope_id = (uint32_t)if_index;
1167
if(quit_now){
1168
errno = EINTR;
1169
goto mandos_end;
1170
}
565
1171
566
1172
if(debug){
567
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
568
port);
569
char addrstr[INET6_ADDRSTRLEN] = "";
570
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
571
sizeof(addrstr)) == NULL){
572
perror("inet_ntop");
573
} else {
574
if(strcmp(addrstr, ip) != 0){
575
fprintf(stderr, "Canonical address form: %s\n", addrstr);
576
}
577
}
578
}
579
580
ret = connect(tcp_sd, &to.in, sizeof(to));
581
if(ret < 0){
582
perror("connect");
583
return -1;
1173
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1174
char interface[IF_NAMESIZE];
1175
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1176
perror_plus("if_indextoname");
1177
} else {
1178
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1179
"\n", ip, interface, (uintmax_t)port);
1180
}
1181
} else {
1182
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1183
ip, (uintmax_t)port);
1184
}
1185
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1186
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1187
if(af == AF_INET6){
1188
ret = getnameinfo((struct sockaddr *)&to,
1189
sizeof(struct sockaddr_in6),
1190
addrstr, sizeof(addrstr), NULL, 0,
1191
NI_NUMERICHOST);
1192
} else {
1193
ret = getnameinfo((struct sockaddr *)&to,
1194
sizeof(struct sockaddr_in),
1195
addrstr, sizeof(addrstr), NULL, 0,
1196
NI_NUMERICHOST);
1197
}
1198
if(ret == EAI_SYSTEM){
1199
perror_plus("getnameinfo");
1200
} else if(ret != 0) {
1201
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1202
} else if(strcmp(addrstr, ip) != 0){
1203
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1204
}
1205
}
1206
1207
if(quit_now){
1208
errno = EINTR;
1209
goto mandos_end;
1210
}
1211
1212
while(true){
1213
if(af == AF_INET6){
1214
ret = connect(tcp_sd, (struct sockaddr *)&to,
1215
sizeof(struct sockaddr_in6));
1216
} else {
1217
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1218
sizeof(struct sockaddr_in));
1219
}
1220
if(ret < 0){
1221
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1222
and if_index != AVAHI_IF_UNSPEC
1223
and connect_to == NULL
1224
and not route_added and
1225
((af == AF_INET6 and not
1226
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1227
&to)->sin6_addr)))
1228
or (af == AF_INET and
1229
/* Not a a IPv4LL address */
1230
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1231
& 0xFFFF0000L) != 0xA9FE0000L))){
1232
/* Work around Avahi bug - Avahi does not announce link-local
1233
addresses if it has a global address, so local hosts with
1234
*only* a link-local address (e.g. Mandos clients) cannot
1235
connect to a Mandos server announced by Avahi on a server
1236
host with a global address. Work around this by retrying
1237
with an explicit route added with the server's address.
1238
1239
Avahi bug reference:
1240
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1241
https://bugs.debian.org/587961
1242
*/
1243
if(debug){
1244
fprintf_plus(stderr, "Mandos server unreachable, trying"
1245
" direct route\n");
1246
}
1247
int e = errno;
1248
route_added = add_local_route(ip, if_index);
1249
if(route_added){
1250
continue;
1251
}
1252
errno = e;
1253
}
1254
if(errno != ECONNREFUSED or debug){
1255
int e = errno;
1256
perror_plus("connect");
1257
errno = e;
1258
}
1259
goto mandos_end;
1260
}
1261
1262
if(quit_now){
1263
errno = EINTR;
1264
goto mandos_end;
1265
}
1266
break;
584
1267
}
585
1268
586
1269
const char *out = mandos_protocol_version;
588
1271
while(true){
589
1272
size_t out_size = strlen(out);
590
1273
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
591
out_size - written));
1274
out_size - written));
592
1275
if(ret == -1){
593
perror("write");
594
retval = -1;
1276
int e = errno;
1277
perror_plus("write");
1278
errno = e;
595
1279
goto mandos_end;
596
1280
}
597
1281
written += (size_t)ret;
605
1289
break;
606
1290
}
607
1291
}
1292
1293
if(quit_now){
1294
errno = EINTR;
1295
goto mandos_end;
1296
}
608
1297
}
609
1298
610
1299
if(debug){
611
fprintf(stderr, "Establishing TLS session with %s\n", ip);
612
}
613
614
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
615
616
do{
1300
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1301
}
1302
1303
if(quit_now){
1304
errno = EINTR;
1305
goto mandos_end;
1306
}
1307
1308
/* This casting via intptr_t is to eliminate warning about casting
1309
an int to a pointer type. This is exactly how the GnuTLS Guile
1310
function "set-session-transport-fd!" does it. */
1311
gnutls_transport_set_ptr(session,
1312
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1313
1314
if(quit_now){
1315
errno = EINTR;
1316
goto mandos_end;
1317
}
1318
1319
do {
617
1320
ret = gnutls_handshake(session);
1321
if(quit_now){
1322
errno = EINTR;
1323
goto mandos_end;
1324
}
618
1325
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
619
1326
620
1327
if(ret != GNUTLS_E_SUCCESS){
621
1328
if(debug){
622
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1329
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
623
1330
gnutls_perror(ret);
624
1331
}
625
retval = -1;
1332
errno = EPROTO;
626
1333
goto mandos_end;
627
1334
}
628
1335
629
1336
/* Read OpenPGP packet that contains the wanted password */
630
1337
631
1338
if(debug){
632
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
633
ip);
1339
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1340
" %s\n", ip);
634
1341
}
635
1342
636
1343
while(true){
637
buffer_capacity = adjustbuffer(&buffer, buffer_length,
638
buffer_capacity);
1344
1345
if(quit_now){
1346
errno = EINTR;
1347
goto mandos_end;
1348
}
1349
1350
buffer_capacity = incbuffer(&buffer, buffer_length,
1351
buffer_capacity);
639
1352
if(buffer_capacity == 0){
640
perror("adjustbuffer");
641
retval = -1;
1353
int e = errno;
1354
perror_plus("incbuffer");
1355
errno = e;
1356
goto mandos_end;
1357
}
1358
1359
if(quit_now){
1360
errno = EINTR;
642
1361
goto mandos_end;
643
1362
}
644
1363
653
1372
case GNUTLS_E_AGAIN:
654
1373
break;
655
1374
case GNUTLS_E_REHANDSHAKE:
656
do{
1375
do {
657
1376
ret = gnutls_handshake(session);
1377
1378
if(quit_now){
1379
errno = EINTR;
1380
goto mandos_end;
1381
}
658
1382
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
659
1383
if(ret < 0){
660
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1384
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1385
"***\n");
661
1386
gnutls_perror(ret);
662
retval = -1;
1387
errno = EPROTO;
663
1388
goto mandos_end;
664
1389
}
665
1390
break;
666
1391
default:
667
fprintf(stderr, "Unknown error while reading data from"
668
" encrypted session with Mandos server\n");
669
retval = -1;
1392
fprintf_plus(stderr, "Unknown error while reading data from"
1393
" encrypted session with Mandos server\n");
670
1394
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1395
errno = EIO;
671
1396
goto mandos_end;
672
1397
}
673
1398
} else {
676
1401
}
677
1402
678
1403
if(debug){
679
fprintf(stderr, "Closing TLS session\n");
680
}
681
682
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1404
fprintf_plus(stderr, "Closing TLS session\n");
1405
}
1406
1407
if(quit_now){
1408
errno = EINTR;
1409
goto mandos_end;
1410
}
1411
1412
do {
1413
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1414
if(quit_now){
1415
errno = EINTR;
1416
goto mandos_end;
1417
}
1418
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
683
1419
684
1420
if(buffer_length > 0){
685
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
686
buffer_length,
687
&decrypted_buffer);
1421
ssize_t decrypted_buffer_size;
1422
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1423
&decrypted_buffer, mc);
688
1424
if(decrypted_buffer_size >= 0){
1425
689
1426
written = 0;
690
1427
while(written < (size_t) decrypted_buffer_size){
1428
if(quit_now){
1429
errno = EINTR;
1430
goto mandos_end;
1431
}
1432
691
1433
ret = (int)fwrite(decrypted_buffer + written, 1,
692
1434
(size_t)decrypted_buffer_size - written,
693
1435
stdout);
694
1436
if(ret == 0 and ferror(stdout)){
1437
int e = errno;
695
1438
if(debug){
696
fprintf(stderr, "Error writing encrypted data: %s\n",
697
strerror(errno));
1439
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1440
strerror(errno));
698
1441
}
699
retval = -1;
700
break;
1442
errno = e;
1443
goto mandos_end;
701
1444
}
702
1445
written += (size_t)ret;
703
1446
}
704
free(decrypted_buffer);
705
} else {
706
retval = -1;
1447
retval = 0;
707
1448
}
708
} else {
709
retval = -1;
710
1449
}
711
1450
712
1451
/* Shutdown procedure */
713
1452
714
1453
mandos_end:
715
free(buffer);
716
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
717
if(ret == -1){
718
perror("close");
1454
{
1455
if(route_added){
1456
if(not delete_local_route(ip, if_index)){
1457
fprintf_plus(stderr, "Failed to delete local route to %s on"
1458
" interface %d", ip, if_index);
1459
}
1460
}
1461
int e = errno;
1462
free(decrypted_buffer);
1463
free(buffer);
1464
if(tcp_sd >= 0){
1465
ret = close(tcp_sd);
1466
}
1467
if(ret == -1){
1468
if(e == 0){
1469
e = errno;
1470
}
1471
perror_plus("close");
1472
}
1473
gnutls_deinit(session);
1474
errno = e;
1475
if(quit_now){
1476
errno = EINTR;
1477
retval = -1;
1478
}
719
1479
}
720
gnutls_deinit(session);
721
1480
return retval;
722
1481
}
723
1482
1483
__attribute__((nonnull))
724
1484
static void resolve_callback(AvahiSServiceResolver *r,
725
1485
AvahiIfIndex interface,
726
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1486
AvahiProtocol proto,
727
1487
AvahiResolverEvent event,
728
1488
const char *name,
729
1489
const char *type,
734
1494
AVAHI_GCC_UNUSED AvahiStringList *txt,
735
1495
AVAHI_GCC_UNUSED AvahiLookupResultFlags
736
1496
flags,
737
void* userdata) {
738
mandos_context *mc = userdata;
739
assert(r);
1497
void *mc){
1498
if(r == NULL){
1499
return;
1500
}
740
1501
741
1502
/* Called whenever a service has been resolved successfully or
742
1503
timed out */
743
1504
744
switch(event) {
1505
if(quit_now){
1506
avahi_s_service_resolver_free(r);
1507
return;
1508
}
1509
1510
switch(event){
745
1511
default:
746
1512
case AVAHI_RESOLVER_FAILURE:
747
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
748
" of type '%s' in domain '%s': %s\n", name, type, domain,
749
avahi_strerror(avahi_server_errno(mc->server)));
1513
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1514
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1515
domain,
1516
avahi_strerror(avahi_server_errno
1517
(((mandos_context*)mc)->server)));
750
1518
break;
751
1519
752
1520
case AVAHI_RESOLVER_FOUND:
754
1522
char ip[AVAHI_ADDRESS_STR_MAX];
755
1523
avahi_address_snprint(ip, sizeof(ip), address);
756
1524
if(debug){
757
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
758
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
759
ip, (intmax_t)interface, port);
1525
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1526
PRIdMAX ") on port %" PRIu16 "\n", name,
1527
host_name, ip, (intmax_t)interface, port);
760
1528
}
761
int ret = start_mandos_communication(ip, port, interface, mc);
1529
int ret = start_mandos_communication(ip, (in_port_t)port,
1530
interface,
1531
avahi_proto_to_af(proto),
1532
mc);
762
1533
if(ret == 0){
763
avahi_simple_poll_quit(mc->simple_poll);
1534
avahi_simple_poll_quit(simple_poll);
1535
} else {
1536
if(not add_server(ip, (in_port_t)port, interface,
1537
avahi_proto_to_af(proto),
1538
&((mandos_context*)mc)->current_server)){
1539
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1540
" list\n", name);
1541
}
764
1542
}
765
1543
}
766
1544
}
767
1545
avahi_s_service_resolver_free(r);
768
1546
}
769
1547
770
static void browse_callback( AvahiSServiceBrowser *b,
771
AvahiIfIndex interface,
772
AvahiProtocol protocol,
773
AvahiBrowserEvent event,
774
const char *name,
775
const char *type,
776
const char *domain,
777
AVAHI_GCC_UNUSED AvahiLookupResultFlags
778
flags,
779
void* userdata) {
780
mandos_context *mc = userdata;
781
assert(b);
1548
static void browse_callback(AvahiSServiceBrowser *b,
1549
AvahiIfIndex interface,
1550
AvahiProtocol protocol,
1551
AvahiBrowserEvent event,
1552
const char *name,
1553
const char *type,
1554
const char *domain,
1555
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1556
flags,
1557
void *mc){
1558
if(b == NULL){
1559
return;
1560
}
782
1561
783
1562
/* Called whenever a new services becomes available on the LAN or
784
1563
is removed from the LAN */
785
1564
786
switch(event) {
1565
if(quit_now){
1566
return;
1567
}
1568
1569
switch(event){
787
1570
default:
788
1571
case AVAHI_BROWSER_FAILURE:
789
1572
790
fprintf(stderr, "(Avahi browser) %s\n",
791
avahi_strerror(avahi_server_errno(mc->server)));
792
avahi_simple_poll_quit(mc->simple_poll);
1573
fprintf_plus(stderr, "(Avahi browser) %s\n",
1574
avahi_strerror(avahi_server_errno
1575
(((mandos_context*)mc)->server)));
1576
avahi_simple_poll_quit(simple_poll);
793
1577
return;
794
1578
795
1579
case AVAHI_BROWSER_NEW:
798
1582
the callback function is called the Avahi server will free the
799
1583
resolver for us. */
800
1584
801
if(!(avahi_s_service_resolver_new(mc->server, interface,
802
protocol, name, type, domain,
803
AVAHI_PROTO_INET6, 0,
804
resolve_callback, mc)))
805
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
806
name, avahi_strerror(avahi_server_errno(mc->server)));
1585
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1586
interface, protocol, name, type,
1587
domain, protocol, 0,
1588
resolve_callback, mc) == NULL)
1589
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1590
" %s\n", name,
1591
avahi_strerror(avahi_server_errno
1592
(((mandos_context*)mc)->server)));
807
1593
break;
808
1594
809
1595
case AVAHI_BROWSER_REMOVE:
812
1598
case AVAHI_BROWSER_ALL_FOR_NOW:
813
1599
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
1600
if(debug){
815
fprintf(stderr, "No Mandos server found, still searching...\n");
1601
fprintf_plus(stderr, "No Mandos server found, still"
1602
" searching...\n");
816
1603
}
817
1604
break;
818
1605
}
819
1606
}
820
1607
1608
/* Signal handler that stops main loop after SIGTERM */
1609
static void handle_sigterm(int sig){
1610
if(quit_now){
1611
return;
1612
}
1613
quit_now = 1;
1614
signal_received = sig;
1615
int old_errno = errno;
1616
/* set main loop to exit */
1617
if(simple_poll != NULL){
1618
avahi_simple_poll_quit(simple_poll);
1619
}
1620
errno = old_errno;
1621
}
1622
1623
__attribute__((nonnull, warn_unused_result))
1624
bool get_flags(const char *ifname, struct ifreq *ifr){
1625
int ret;
1626
int old_errno;
1627
1628
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1629
if(s < 0){
1630
old_errno = errno;
1631
perror_plus("socket");
1632
errno = old_errno;
1633
return false;
1634
}
1635
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1636
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1637
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1638
if(ret == -1){
1639
if(debug){
1640
old_errno = errno;
1641
perror_plus("ioctl SIOCGIFFLAGS");
1642
errno = old_errno;
1643
}
1644
return false;
1645
}
1646
return true;
1647
}
1648
1649
__attribute__((nonnull, warn_unused_result))
1650
bool good_flags(const char *ifname, const struct ifreq *ifr){
1651
1652
/* Reject the loopback device */
1653
if(ifr->ifr_flags & IFF_LOOPBACK){
1654
if(debug){
1655
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1656
ifname);
1657
}
1658
return false;
1659
}
1660
/* Accept point-to-point devices only if connect_to is specified */
1661
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1662
if(debug){
1663
fprintf_plus(stderr, "Accepting point-to-point interface"
1664
" \"%s\"\n", ifname);
1665
}
1666
return true;
1667
}
1668
/* Otherwise, reject non-broadcast-capable devices */
1669
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1670
if(debug){
1671
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1672
" \"%s\"\n", ifname);
1673
}
1674
return false;
1675
}
1676
/* Reject non-ARP interfaces (including dummy interfaces) */
1677
if(ifr->ifr_flags & IFF_NOARP){
1678
if(debug){
1679
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1680
ifname);
1681
}
1682
return false;
1683
}
1684
1685
/* Accept this device */
1686
if(debug){
1687
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1688
}
1689
return true;
1690
}
1691
1692
/*
1693
* This function determines if a directory entry in /sys/class/net
1694
* corresponds to an acceptable network device.
1695
* (This function is passed to scandir(3) as a filter function.)
1696
*/
1697
__attribute__((nonnull, warn_unused_result))
1698
int good_interface(const struct dirent *if_entry){
1699
if(if_entry->d_name[0] == '.'){
1700
return 0;
1701
}
1702
1703
struct ifreq ifr;
1704
if(not get_flags(if_entry->d_name, &ifr)){
1705
if(debug){
1706
fprintf_plus(stderr, "Failed to get flags for interface "
1707
"\"%s\"\n", if_entry->d_name);
1708
}
1709
return 0;
1710
}
1711
1712
if(not good_flags(if_entry->d_name, &ifr)){
1713
return 0;
1714
}
1715
return 1;
1716
}
1717
1718
/*
1719
* This function determines if a network interface is up.
1720
*/
1721
__attribute__((nonnull, warn_unused_result))
1722
bool interface_is_up(const char *interface){
1723
struct ifreq ifr;
1724
if(not get_flags(interface, &ifr)){
1725
if(debug){
1726
fprintf_plus(stderr, "Failed to get flags for interface "
1727
"\"%s\"\n", interface);
1728
}
1729
return false;
1730
}
1731
1732
return (bool)(ifr.ifr_flags & IFF_UP);
1733
}
1734
1735
/*
1736
* This function determines if a network interface is running
1737
*/
1738
__attribute__((nonnull, warn_unused_result))
1739
bool interface_is_running(const char *interface){
1740
struct ifreq ifr;
1741
if(not get_flags(interface, &ifr)){
1742
if(debug){
1743
fprintf_plus(stderr, "Failed to get flags for interface "
1744
"\"%s\"\n", interface);
1745
}
1746
return false;
1747
}
1748
1749
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1750
}
1751
1752
__attribute__((nonnull, pure, warn_unused_result))
1753
int notdotentries(const struct dirent *direntry){
1754
/* Skip "." and ".." */
1755
if(direntry->d_name[0] == '.'
1756
and (direntry->d_name[1] == '\0'
1757
or (direntry->d_name[1] == '.'
1758
and direntry->d_name[2] == '\0'))){
1759
return 0;
1760
}
1761
return 1;
1762
}
1763
1764
/* Is this directory entry a runnable program? */
1765
__attribute__((nonnull, warn_unused_result))
1766
int runnable_hook(const struct dirent *direntry){
1767
int ret;
1768
size_t sret;
1769
struct stat st;
1770
1771
if((direntry->d_name)[0] == '\0'){
1772
/* Empty name? */
1773
return 0;
1774
}
1775
1776
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1777
"abcdefghijklmnopqrstuvwxyz"
1778
"0123456789"
1779
"_.-");
1780
if((direntry->d_name)[sret] != '\0'){
1781
/* Contains non-allowed characters */
1782
if(debug){
1783
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1784
direntry->d_name);
1785
}
1786
return 0;
1787
}
1788
1789
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1790
if(ret == -1){
1791
if(debug){
1792
perror_plus("Could not stat hook");
1793
}
1794
return 0;
1795
}
1796
if(not (S_ISREG(st.st_mode))){
1797
/* Not a regular file */
1798
if(debug){
1799
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1800
direntry->d_name);
1801
}
1802
return 0;
1803
}
1804
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1805
/* Not executable */
1806
if(debug){
1807
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1808
direntry->d_name);
1809
}
1810
return 0;
1811
}
1812
if(debug){
1813
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1814
direntry->d_name);
1815
}
1816
return 1;
1817
}
1818
1819
__attribute__((nonnull, warn_unused_result))
1820
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1821
mandos_context *mc){
1822
int ret;
1823
struct timespec now;
1824
struct timespec waited_time;
1825
intmax_t block_time;
1826
1827
while(true){
1828
if(mc->current_server == NULL){
1829
if(debug){
1830
fprintf_plus(stderr, "Wait until first server is found."
1831
" No timeout!\n");
1832
}
1833
ret = avahi_simple_poll_iterate(s, -1);
1834
} else {
1835
if(debug){
1836
fprintf_plus(stderr, "Check current_server if we should run"
1837
" it, or wait\n");
1838
}
1839
/* the current time */
1840
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1841
if(ret == -1){
1842
perror_plus("clock_gettime");
1843
return -1;
1844
}
1845
/* Calculating in ms how long time between now and server
1846
who we visted longest time ago. Now - last seen. */
1847
waited_time.tv_sec = (now.tv_sec
1848
- mc->current_server->last_seen.tv_sec);
1849
waited_time.tv_nsec = (now.tv_nsec
1850
- mc->current_server->last_seen.tv_nsec);
1851
/* total time is 10s/10,000ms.
1852
Converting to s from ms by dividing by 1,000,
1853
and ns to ms by dividing by 1,000,000. */
1854
block_time = ((retry_interval
1855
- ((intmax_t)waited_time.tv_sec * 1000))
1856
- ((intmax_t)waited_time.tv_nsec / 1000000));
1857
1858
if(debug){
1859
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1860
block_time);
1861
}
1862
1863
if(block_time <= 0){
1864
ret = start_mandos_communication(mc->current_server->ip,
1865
mc->current_server->port,
1866
mc->current_server->if_index,
1867
mc->current_server->af, mc);
1868
if(ret == 0){
1869
avahi_simple_poll_quit(s);
1870
return 0;
1871
}
1872
ret = clock_gettime(CLOCK_MONOTONIC,
1873
&mc->current_server->last_seen);
1874
if(ret == -1){
1875
perror_plus("clock_gettime");
1876
return -1;
1877
}
1878
mc->current_server = mc->current_server->next;
1879
block_time = 0; /* Call avahi to find new Mandos
1880
servers, but don't block */
1881
}
1882
1883
ret = avahi_simple_poll_iterate(s, (int)block_time);
1884
}
1885
if(ret != 0){
1886
if(ret > 0 or errno != EINTR){
1887
return (ret != 1) ? ret : 0;
1888
}
1889
}
1890
}
1891
}
1892
1893
__attribute__((nonnull))
1894
void run_network_hooks(const char *mode, const char *interface,
1895
const float delay){
1896
struct dirent **direntries = NULL;
1897
if(hookdir_fd == -1){
1898
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1899
| O_CLOEXEC);
1900
if(hookdir_fd == -1){
1901
if(errno == ENOENT){
1902
if(debug){
1903
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1904
" found\n", hookdir);
1905
}
1906
} else {
1907
perror_plus("open");
1908
}
1909
return;
1910
}
1911
}
1912
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1913
runnable_hook, alphasort);
1914
if(numhooks == -1){
1915
perror_plus("scandir");
1916
return;
1917
}
1918
struct dirent *direntry;
1919
int ret;
1920
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1921
if(devnull == -1){
1922
perror_plus("open(\"/dev/null\", O_RDONLY)");
1923
return;
1924
}
1925
for(int i = 0; i < numhooks; i++){
1926
direntry = direntries[i];
1927
if(debug){
1928
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1929
direntry->d_name);
1930
}
1931
pid_t hook_pid = fork();
1932
if(hook_pid == 0){
1933
/* Child */
1934
/* Raise privileges */
1935
errno = raise_privileges_permanently();
1936
if(errno != 0){
1937
perror_plus("Failed to raise privileges");
1938
_exit(EX_NOPERM);
1939
}
1940
/* Set group */
1941
errno = 0;
1942
ret = setgid(0);
1943
if(ret == -1){
1944
perror_plus("setgid");
1945
_exit(EX_NOPERM);
1946
}
1947
/* Reset supplementary groups */
1948
errno = 0;
1949
ret = setgroups(0, NULL);
1950
if(ret == -1){
1951
perror_plus("setgroups");
1952
_exit(EX_NOPERM);
1953
}
1954
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1955
if(ret == -1){
1956
perror_plus("setenv");
1957
_exit(EX_OSERR);
1958
}
1959
ret = setenv("DEVICE", interface, 1);
1960
if(ret == -1){
1961
perror_plus("setenv");
1962
_exit(EX_OSERR);
1963
}
1964
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1965
if(ret == -1){
1966
perror_plus("setenv");
1967
_exit(EX_OSERR);
1968
}
1969
ret = setenv("MODE", mode, 1);
1970
if(ret == -1){
1971
perror_plus("setenv");
1972
_exit(EX_OSERR);
1973
}
1974
char *delaystring;
1975
ret = asprintf(&delaystring, "%f", (double)delay);
1976
if(ret == -1){
1977
perror_plus("asprintf");
1978
_exit(EX_OSERR);
1979
}
1980
ret = setenv("DELAY", delaystring, 1);
1981
if(ret == -1){
1982
free(delaystring);
1983
perror_plus("setenv");
1984
_exit(EX_OSERR);
1985
}
1986
free(delaystring);
1987
if(connect_to != NULL){
1988
ret = setenv("CONNECT", connect_to, 1);
1989
if(ret == -1){
1990
perror_plus("setenv");
1991
_exit(EX_OSERR);
1992
}
1993
}
1994
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
1995
direntry->d_name,
1996
O_RDONLY));
1997
if(hook_fd == -1){
1998
perror_plus("openat");
1999
_exit(EXIT_FAILURE);
2000
}
2001
if(close(hookdir_fd) == -1){
2002
perror_plus("close");
2003
_exit(EXIT_FAILURE);
2004
}
2005
ret = dup2(devnull, STDIN_FILENO);
2006
if(ret == -1){
2007
perror_plus("dup2(devnull, STDIN_FILENO)");
2008
_exit(EX_OSERR);
2009
}
2010
ret = close(devnull);
2011
if(ret == -1){
2012
perror_plus("close");
2013
_exit(EX_OSERR);
2014
}
2015
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2016
if(ret == -1){
2017
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2018
_exit(EX_OSERR);
2019
}
2020
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2021
environ) == -1){
2022
perror_plus("fexecve");
2023
_exit(EXIT_FAILURE);
2024
}
2025
} else {
2026
if(hook_pid == -1){
2027
perror_plus("fork");
2028
free(direntry);
2029
continue;
2030
}
2031
int status;
2032
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2033
perror_plus("waitpid");
2034
free(direntry);
2035
continue;
2036
}
2037
if(WIFEXITED(status)){
2038
if(WEXITSTATUS(status) != 0){
2039
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2040
" with status %d\n", direntry->d_name,
2041
WEXITSTATUS(status));
2042
free(direntry);
2043
continue;
2044
}
2045
} else if(WIFSIGNALED(status)){
2046
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2047
" signal %d\n", direntry->d_name,
2048
WTERMSIG(status));
2049
free(direntry);
2050
continue;
2051
} else {
2052
fprintf_plus(stderr, "Warning: network hook \"%s\""
2053
" crashed\n", direntry->d_name);
2054
free(direntry);
2055
continue;
2056
}
2057
}
2058
if(debug){
2059
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2060
direntry->d_name);
2061
}
2062
free(direntry);
2063
}
2064
free(direntries);
2065
if(close(hookdir_fd) == -1){
2066
perror_plus("close");
2067
} else {
2068
hookdir_fd = -1;
2069
}
2070
close(devnull);
2071
}
2072
2073
__attribute__((nonnull, warn_unused_result))
2074
int bring_up_interface(const char *const interface,
2075
const float delay){
2076
int old_errno = errno;
2077
int ret;
2078
struct ifreq network;
2079
unsigned int if_index = if_nametoindex(interface);
2080
if(if_index == 0){
2081
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2082
errno = old_errno;
2083
return ENXIO;
2084
}
2085
2086
if(quit_now){
2087
errno = old_errno;
2088
return EINTR;
2089
}
2090
2091
if(not interface_is_up(interface)){
2092
int ret_errno = 0;
2093
int ioctl_errno = 0;
2094
if(not get_flags(interface, &network)){
2095
ret_errno = errno;
2096
fprintf_plus(stderr, "Failed to get flags for interface "
2097
"\"%s\"\n", interface);
2098
errno = old_errno;
2099
return ret_errno;
2100
}
2101
network.ifr_flags |= IFF_UP; /* set flag */
2102
2103
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2104
if(sd == -1){
2105
ret_errno = errno;
2106
perror_plus("socket");
2107
errno = old_errno;
2108
return ret_errno;
2109
}
2110
2111
if(quit_now){
2112
ret = close(sd);
2113
if(ret == -1){
2114
perror_plus("close");
2115
}
2116
errno = old_errno;
2117
return EINTR;
2118
}
2119
2120
if(debug){
2121
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2122
interface);
2123
}
2124
2125
/* Raise privileges */
2126
ret_errno = raise_privileges();
2127
if(ret_errno != 0){
2128
errno = ret_errno;
2129
perror_plus("Failed to raise privileges");
2130
}
2131
2132
#ifdef __linux__
2133
int ret_linux;
2134
bool restore_loglevel = false;
2135
if(ret_errno == 0){
2136
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2137
messages about the network interface to mess up the prompt */
2138
ret_linux = klogctl(8, NULL, 5);
2139
if(ret_linux == -1){
2140
perror_plus("klogctl");
2141
} else {
2142
restore_loglevel = true;
2143
}
2144
}
2145
#endif /* __linux__ */
2146
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2147
ioctl_errno = errno;
2148
#ifdef __linux__
2149
if(restore_loglevel){
2150
ret_linux = klogctl(7, NULL, 0);
2151
if(ret_linux == -1){
2152
perror_plus("klogctl");
2153
}
2154
}
2155
#endif /* __linux__ */
2156
2157
/* If raise_privileges() succeeded above */
2158
if(ret_errno == 0){
2159
/* Lower privileges */
2160
ret_errno = lower_privileges();
2161
if(ret_errno != 0){
2162
errno = ret_errno;
2163
perror_plus("Failed to lower privileges");
2164
}
2165
}
2166
2167
/* Close the socket */
2168
ret = close(sd);
2169
if(ret == -1){
2170
perror_plus("close");
2171
}
2172
2173
if(ret_setflags == -1){
2174
errno = ioctl_errno;
2175
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2176
errno = old_errno;
2177
return ioctl_errno;
2178
}
2179
} else if(debug){
2180
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2181
interface);
2182
}
2183
2184
/* Sleep checking until interface is running.
2185
Check every 0.25s, up to total time of delay */
2186
for(int i=0; i < delay * 4; i++){
2187
if(interface_is_running(interface)){
2188
break;
2189
}
2190
struct timespec sleeptime = { .tv_nsec = 250000000 };
2191
ret = nanosleep(&sleeptime, NULL);
2192
if(ret == -1 and errno != EINTR){
2193
perror_plus("nanosleep");
2194
}
2195
}
2196
2197
errno = old_errno;
2198
return 0;
2199
}
2200
2201
__attribute__((nonnull, warn_unused_result))
2202
int take_down_interface(const char *const interface){
2203
int old_errno = errno;
2204
struct ifreq network;
2205
unsigned int if_index = if_nametoindex(interface);
2206
if(if_index == 0){
2207
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2208
errno = old_errno;
2209
return ENXIO;
2210
}
2211
if(interface_is_up(interface)){
2212
int ret_errno = 0;
2213
int ioctl_errno = 0;
2214
if(not get_flags(interface, &network) and debug){
2215
ret_errno = errno;
2216
fprintf_plus(stderr, "Failed to get flags for interface "
2217
"\"%s\"\n", interface);
2218
errno = old_errno;
2219
return ret_errno;
2220
}
2221
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2222
2223
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2224
if(sd == -1){
2225
ret_errno = errno;
2226
perror_plus("socket");
2227
errno = old_errno;
2228
return ret_errno;
2229
}
2230
2231
if(debug){
2232
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2233
interface);
2234
}
2235
2236
/* Raise privileges */
2237
ret_errno = raise_privileges();
2238
if(ret_errno != 0){
2239
errno = ret_errno;
2240
perror_plus("Failed to raise privileges");
2241
}
2242
2243
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2244
ioctl_errno = errno;
2245
2246
/* If raise_privileges() succeeded above */
2247
if(ret_errno == 0){
2248
/* Lower privileges */
2249
ret_errno = lower_privileges();
2250
if(ret_errno != 0){
2251
errno = ret_errno;
2252
perror_plus("Failed to lower privileges");
2253
}
2254
}
2255
2256
/* Close the socket */
2257
int ret = close(sd);
2258
if(ret == -1){
2259
perror_plus("close");
2260
}
2261
2262
if(ret_setflags == -1){
2263
errno = ioctl_errno;
2264
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2265
errno = old_errno;
2266
return ioctl_errno;
2267
}
2268
} else if(debug){
2269
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2270
interface);
2271
}
2272
2273
errno = old_errno;
2274
return 0;
2275
}
2276
821
2277
int main(int argc, char *argv[]){
822
AvahiSServiceBrowser *sb = NULL;
823
int error;
824
int ret;
825
intmax_t tmpmax;
826
int numchars;
827
int exitcode = EXIT_SUCCESS;
828
const char *interface = "eth0";
829
struct ifreq network;
830
int sd;
831
uid_t uid;
832
gid_t gid;
833
char *connect_to = NULL;
834
char tempdir[] = "/tmp/mandosXXXXXX";
835
bool tempdir_created = false;
836
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
837
const char *seckey = PATHDIR "/" SECKEY;
838
const char *pubkey = PATHDIR "/" PUBKEY;
839
840
mandos_context mc = { .simple_poll = NULL, .server = NULL,
841
.dh_bits = 1024, .priority = "SECURE256"
842
":!CTYPE-X.509:+CTYPE-OPENPGP" };
843
bool gnutls_initialized = false;
844
bool gpgme_initialized = false;
845
846
{
847
struct argp_option options[] = {
848
{ .name = "debug", .key = 128,
849
.doc = "Debug mode", .group = 3 },
850
{ .name = "connect", .key = 'c',
851
.arg = "ADDRESS:PORT",
852
.doc = "Connect directly to a specific Mandos server",
853
.group = 1 },
854
{ .name = "interface", .key = 'i',
855
.arg = "NAME",
856
.doc = "Interface that will be used to search for Mandos"
857
" servers",
858
.group = 1 },
859
{ .name = "seckey", .key = 's',
860
.arg = "FILE",
861
.doc = "OpenPGP secret key file base name",
862
.group = 1 },
863
{ .name = "pubkey", .key = 'p',
864
.arg = "FILE",
865
.doc = "OpenPGP public key file base name",
866
.group = 2 },
867
{ .name = "dh-bits", .key = 129,
868
.arg = "BITS",
869
.doc = "Bit length of the prime number used in the"
870
" Diffie-Hellman key exchange",
871
.group = 2 },
872
{ .name = "priority", .key = 130,
873
.arg = "STRING",
874
.doc = "GnuTLS priority string for the TLS handshake",
875
.group = 1 },
876
{ .name = NULL }
877
};
878
879
error_t parse_opt(int key, char *arg,
880
struct argp_state *state) {
881
switch(key) {
882
case 128: /* --debug */
883
debug = true;
884
break;
885
case 'c': /* --connect */
886
connect_to = arg;
887
break;
888
case 'i': /* --interface */
889
interface = arg;
890
break;
891
case 's': /* --seckey */
892
seckey = arg;
893
break;
894
case 'p': /* --pubkey */
895
pubkey = arg;
896
break;
897
case 129: /* --dh-bits */
898
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
899
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
900
or arg[numchars] != '\0'){
901
fprintf(stderr, "Bad number of DH bits\n");
902
exit(EXIT_FAILURE);
903
}
904
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
905
break;
906
case 130: /* --priority */
907
mc.priority = arg;
908
break;
909
case ARGP_KEY_ARG:
910
argp_usage(state);
911
case ARGP_KEY_END:
912
break;
913
default:
914
return ARGP_ERR_UNKNOWN;
915
}
916
return 0;
917
}
918
919
struct argp argp = { .options = options, .parser = parse_opt,
920
.args_doc = "",
921
.doc = "Mandos client -- Get and decrypt"
922
" passwords from a Mandos server" };
923
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
924
if(ret == ARGP_ERR_UNKNOWN){
925
fprintf(stderr, "Unknown error while parsing arguments\n");
926
exitcode = EXIT_FAILURE;
927
goto end;
928
}
929
}
930
931
/* If the interface is down, bring it up */
932
{
933
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
934
if(sd < 0) {
935
perror("socket");
936
exitcode = EXIT_FAILURE;
937
goto end;
938
}
939
strcpy(network.ifr_name, interface);
940
ret = ioctl(sd, SIOCGIFFLAGS, &network);
941
if(ret == -1){
942
perror("ioctl SIOCGIFFLAGS");
943
exitcode = EXIT_FAILURE;
944
goto end;
945
}
946
if((network.ifr_flags & IFF_UP) == 0){
947
network.ifr_flags |= IFF_UP;
948
ret = ioctl(sd, SIOCSIFFLAGS, &network);
949
if(ret == -1){
950
perror("ioctl SIOCSIFFLAGS");
951
exitcode = EXIT_FAILURE;
952
goto end;
953
}
954
}
955
ret = (int)TEMP_FAILURE_RETRY(close(sd));
956
if(ret == -1){
957
perror("close");
958
}
959
}
960
961
uid = getuid();
962
gid = getgid();
963
964
ret = setuid(uid);
965
if(ret == -1){
966
perror("setuid");
967
}
968
969
setgid(gid);
970
if(ret == -1){
971
perror("setgid");
972
}
973
974
ret = init_gnutls_global(&mc, pubkey, seckey);
975
if(ret == -1){
976
fprintf(stderr, "init_gnutls_global failed\n");
977
exitcode = EXIT_FAILURE;
978
goto end;
979
} else {
980
gnutls_initialized = true;
981
}
982
983
if(mkdtemp(tempdir) == NULL){
984
perror("mkdtemp");
985
goto end;
986
}
987
tempdir_created = true;
988
989
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
990
fprintf(stderr, "init_gpgme failed\n");
991
exitcode = EXIT_FAILURE;
992
goto end;
993
} else {
994
gpgme_initialized = true;
995
}
996
997
if_index = (AvahiIfIndex) if_nametoindex(interface);
998
if(if_index == 0){
999
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1000
exitcode = EXIT_FAILURE;
1001
goto end;
1002
}
1003
1004
if(connect_to != NULL){
1005
/* Connect directly, do not use Zeroconf */
1006
/* (Mainly meant for debugging) */
1007
char *address = strrchr(connect_to, ':');
1008
if(address == NULL){
1009
fprintf(stderr, "No colon in address\n");
1010
exitcode = EXIT_FAILURE;
1011
goto end;
1012
}
1013
uint16_t port;
1014
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1015
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1016
or address[numchars+1] != '\0'){
1017
fprintf(stderr, "Bad port number\n");
1018
exitcode = EXIT_FAILURE;
1019
goto end;
1020
}
1021
port = (uint16_t)tmpmax;
1022
*address = '\0';
1023
address = connect_to;
1024
ret = start_mandos_communication(address, port, if_index, &mc);
1025
if(ret < 0){
1026
exitcode = EXIT_FAILURE;
1027
} else {
1028
exitcode = EXIT_SUCCESS;
1029
}
1030
goto end;
1031
}
1032
1033
if(not debug){
1034
avahi_set_log_function(empty_log);
1035
}
1036
1037
/* Initialize the pseudo-RNG for Avahi */
1038
srand((unsigned int) time(NULL));
1039
1040
/* Allocate main Avahi loop object */
1041
mc.simple_poll = avahi_simple_poll_new();
1042
if(mc.simple_poll == NULL) {
1043
fprintf(stderr, "Avahi: Failed to create simple poll"
1044
" object.\n");
1045
exitcode = EXIT_FAILURE;
1046
goto end;
1047
}
1048
1049
{
1050
AvahiServerConfig config;
1051
/* Do not publish any local Zeroconf records */
1052
avahi_server_config_init(&config);
1053
config.publish_hinfo = 0;
1054
config.publish_addresses = 0;
1055
config.publish_workstation = 0;
1056
config.publish_domain = 0;
1057
1058
/* Allocate a new server */
1059
mc.server = avahi_server_new(avahi_simple_poll_get
1060
(mc.simple_poll), &config, NULL,
1061
NULL, &error);
1062
1063
/* Free the Avahi configuration data */
1064
avahi_server_config_free(&config);
1065
}
1066
1067
/* Check if creating the Avahi server object succeeded */
1068
if(mc.server == NULL) {
1069
fprintf(stderr, "Failed to create Avahi server: %s\n",
1070
avahi_strerror(error));
1071
exitcode = EXIT_FAILURE;
1072
goto end;
1073
}
1074
1075
/* Create the Avahi service browser */
1076
sb = avahi_s_service_browser_new(mc.server, if_index,
1077
AVAHI_PROTO_INET6,
1078
"_mandos._tcp", NULL, 0,
1079
browse_callback, &mc);
1080
if(sb == NULL) {
1081
fprintf(stderr, "Failed to create service browser: %s\n",
1082
avahi_strerror(avahi_server_errno(mc.server)));
1083
exitcode = EXIT_FAILURE;
1084
goto end;
1085
}
1086
1087
/* Run the main loop */
1088
2278
mandos_context mc = { .server = NULL, .dh_bits = 0,
2279
.priority = "SECURE256:!CTYPE-X.509"
2280
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2281
.current_server = NULL, .interfaces = NULL,
2282
.interfaces_size = 0 };
2283
AvahiSServiceBrowser *sb = NULL;
2284
error_t ret_errno;
2285
int ret;
2286
intmax_t tmpmax;
2287
char *tmp;
2288
int exitcode = EXIT_SUCCESS;
2289
char *interfaces_to_take_down = NULL;
2290
size_t interfaces_to_take_down_size = 0;
2291
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2292
char old_tempdir[] = "/tmp/mandosXXXXXX";
2293
char *tempdir = NULL;
2294
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2295
const char *seckey = PATHDIR "/" SECKEY;
2296
const char *pubkey = PATHDIR "/" PUBKEY;
2297
const char *dh_params_file = NULL;
2298
char *interfaces_hooks = NULL;
2299
2300
bool gnutls_initialized = false;
2301
bool gpgme_initialized = false;
2302
float delay = 2.5f;
2303
double retry_interval = 10; /* 10s between trying a server and
2304
retrying the same server again */
2305
2306
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2307
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2308
2309
uid = getuid();
2310
gid = getgid();
2311
2312
/* Lower any group privileges we might have, just to be safe */
2313
errno = 0;
2314
ret = setgid(gid);
2315
if(ret == -1){
2316
perror_plus("setgid");
2317
}
2318
2319
/* Lower user privileges (temporarily) */
2320
errno = 0;
2321
ret = seteuid(uid);
2322
if(ret == -1){
2323
perror_plus("seteuid");
2324
}
2325
2326
if(quit_now){
2327
goto end;
2328
}
2329
2330
{
2331
struct argp_option options[] = {
2332
{ .name = "debug", .key = 128,
2333
.doc = "Debug mode", .group = 3 },
2334
{ .name = "connect", .key = 'c',
2335
.arg = "ADDRESS:PORT",
2336
.doc = "Connect directly to a specific Mandos server",
2337
.group = 1 },
2338
{ .name = "interface", .key = 'i',
2339
.arg = "NAME",
2340
.doc = "Network interface that will be used to search for"
2341
" Mandos servers",
2342
.group = 1 },
2343
{ .name = "seckey", .key = 's',
2344
.arg = "FILE",
2345
.doc = "OpenPGP secret key file base name",
2346
.group = 1 },
2347
{ .name = "pubkey", .key = 'p',
2348
.arg = "FILE",
2349
.doc = "OpenPGP public key file base name",
2350
.group = 2 },
2351
{ .name = "dh-bits", .key = 129,
2352
.arg = "BITS",
2353
.doc = "Bit length of the prime number used in the"
2354
" Diffie-Hellman key exchange",
2355
.group = 2 },
2356
{ .name = "dh-params", .key = 134,
2357
.arg = "FILE",
2358
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2359
" for the Diffie-Hellman key exchange",
2360
.group = 2 },
2361
{ .name = "priority", .key = 130,
2362
.arg = "STRING",
2363
.doc = "GnuTLS priority string for the TLS handshake",
2364
.group = 1 },
2365
{ .name = "delay", .key = 131,
2366
.arg = "SECONDS",
2367
.doc = "Maximum delay to wait for interface startup",
2368
.group = 2 },
2369
{ .name = "retry", .key = 132,
2370
.arg = "SECONDS",
2371
.doc = "Retry interval used when denied by the Mandos server",
2372
.group = 2 },
2373
{ .name = "network-hook-dir", .key = 133,
2374
.arg = "DIR",
2375
.doc = "Directory where network hooks are located",
2376
.group = 2 },
2377
/*
2378
* These reproduce what we would get without ARGP_NO_HELP
2379
*/
2380
{ .name = "help", .key = '?',
2381
.doc = "Give this help list", .group = -1 },
2382
{ .name = "usage", .key = -3,
2383
.doc = "Give a short usage message", .group = -1 },
2384
{ .name = "version", .key = 'V',
2385
.doc = "Print program version", .group = -1 },
2386
{ .name = NULL }
2387
};
2388
2389
error_t parse_opt(int key, char *arg,
2390
struct argp_state *state){
2391
errno = 0;
2392
switch(key){
2393
case 128: /* --debug */
2394
debug = true;
2395
break;
2396
case 'c': /* --connect */
2397
connect_to = arg;
2398
break;
2399
case 'i': /* --interface */
2400
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2401
arg, (int)',');
2402
if(ret_errno != 0){
2403
argp_error(state, "%s", strerror(ret_errno));
2404
}
2405
break;
2406
case 's': /* --seckey */
2407
seckey = arg;
2408
break;
2409
case 'p': /* --pubkey */
2410
pubkey = arg;
2411
break;
2412
case 129: /* --dh-bits */
2413
errno = 0;
2414
tmpmax = strtoimax(arg, &tmp, 10);
2415
if(errno != 0 or tmp == arg or *tmp != '\0'
2416
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2417
argp_error(state, "Bad number of DH bits");
2418
}
2419
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2420
break;
2421
case 134: /* --dh-params */
2422
dh_params_file = arg;
2423
break;
2424
case 130: /* --priority */
2425
mc.priority = arg;
2426
break;
2427
case 131: /* --delay */
2428
errno = 0;
2429
delay = strtof(arg, &tmp);
2430
if(errno != 0 or tmp == arg or *tmp != '\0'){
2431
argp_error(state, "Bad delay");
2432
}
2433
case 132: /* --retry */
2434
errno = 0;
2435
retry_interval = strtod(arg, &tmp);
2436
if(errno != 0 or tmp == arg or *tmp != '\0'
2437
or (retry_interval * 1000) > INT_MAX
2438
or retry_interval < 0){
2439
argp_error(state, "Bad retry interval");
2440
}
2441
break;
2442
case 133: /* --network-hook-dir */
2443
hookdir = arg;
2444
break;
2445
/*
2446
* These reproduce what we would get without ARGP_NO_HELP
2447
*/
2448
case '?': /* --help */
2449
argp_state_help(state, state->out_stream,
2450
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2451
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2452
case -3: /* --usage */
2453
argp_state_help(state, state->out_stream,
2454
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2455
case 'V': /* --version */
2456
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2457
exit(argp_err_exit_status);
2458
break;
2459
default:
2460
return ARGP_ERR_UNKNOWN;
2461
}
2462
return errno;
2463
}
2464
2465
struct argp argp = { .options = options, .parser = parse_opt,
2466
.args_doc = "",
2467
.doc = "Mandos client -- Get and decrypt"
2468
" passwords from a Mandos server" };
2469
ret_errno = argp_parse(&argp, argc, argv,
2470
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2471
switch(ret_errno){
2472
case 0:
2473
break;
2474
case ENOMEM:
2475
default:
2476
errno = ret_errno;
2477
perror_plus("argp_parse");
2478
exitcode = EX_OSERR;
2479
goto end;
2480
case EINVAL:
2481
exitcode = EX_USAGE;
2482
goto end;
2483
}
2484
}
2485
2486
{
2487
/* Work around Debian bug #633582:
2488
<http://bugs.debian.org/633582> */
2489
2490
/* Re-raise privileges */
2491
ret = raise_privileges();
2492
if(ret != 0){
2493
errno = ret;
2494
perror_plus("Failed to raise privileges");
2495
} else {
2496
struct stat st;
2497
2498
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2499
int seckey_fd = open(seckey, O_RDONLY);
2500
if(seckey_fd == -1){
2501
perror_plus("open");
2502
} else {
2503
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2504
if(ret == -1){
2505
perror_plus("fstat");
2506
} else {
2507
if(S_ISREG(st.st_mode)
2508
and st.st_uid == 0 and st.st_gid == 0){
2509
ret = fchown(seckey_fd, uid, gid);
2510
if(ret == -1){
2511
perror_plus("fchown");
2512
}
2513
}
2514
}
2515
close(seckey_fd);
2516
}
2517
}
2518
2519
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2520
int pubkey_fd = open(pubkey, O_RDONLY);
2521
if(pubkey_fd == -1){
2522
perror_plus("open");
2523
} else {
2524
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2525
if(ret == -1){
2526
perror_plus("fstat");
2527
} else {
2528
if(S_ISREG(st.st_mode)
2529
and st.st_uid == 0 and st.st_gid == 0){
2530
ret = fchown(pubkey_fd, uid, gid);
2531
if(ret == -1){
2532
perror_plus("fchown");
2533
}
2534
}
2535
}
2536
close(pubkey_fd);
2537
}
2538
}
2539
2540
if(dh_params_file != NULL
2541
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2542
int dhparams_fd = open(dh_params_file, O_RDONLY);
2543
if(dhparams_fd == -1){
2544
perror_plus("open");
2545
} else {
2546
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2547
if(ret == -1){
2548
perror_plus("fstat");
2549
} else {
2550
if(S_ISREG(st.st_mode)
2551
and st.st_uid == 0 and st.st_gid == 0){
2552
ret = fchown(dhparams_fd, uid, gid);
2553
if(ret == -1){
2554
perror_plus("fchown");
2555
}
2556
}
2557
}
2558
close(dhparams_fd);
2559
}
2560
}
2561
2562
/* Lower privileges */
2563
ret = lower_privileges();
2564
if(ret != 0){
2565
errno = ret;
2566
perror_plus("Failed to lower privileges");
2567
}
2568
}
2569
}
2570
2571
/* Remove invalid interface names (except "none") */
2572
{
2573
char *interface = NULL;
2574
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2575
interface))){
2576
if(strcmp(interface, "none") != 0
2577
and if_nametoindex(interface) == 0){
2578
if(interface[0] != '\0'){
2579
fprintf_plus(stderr, "Not using nonexisting interface"
2580
" \"%s\"\n", interface);
2581
}
2582
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2583
interface = NULL;
2584
}
2585
}
2586
}
2587
2588
/* Run network hooks */
2589
{
2590
if(mc.interfaces != NULL){
2591
interfaces_hooks = malloc(mc.interfaces_size);
2592
if(interfaces_hooks == NULL){
2593
perror_plus("malloc");
2594
goto end;
2595
}
2596
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2597
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2598
}
2599
run_network_hooks("start", interfaces_hooks != NULL ?
2600
interfaces_hooks : "", delay);
2601
}
2602
2603
if(not debug){
2604
avahi_set_log_function(empty_log);
2605
}
2606
2607
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2608
from the signal handler */
2609
/* Initialize the pseudo-RNG for Avahi */
2610
srand((unsigned int) time(NULL));
2611
simple_poll = avahi_simple_poll_new();
2612
if(simple_poll == NULL){
2613
fprintf_plus(stderr,
2614
"Avahi: Failed to create simple poll object.\n");
2615
exitcode = EX_UNAVAILABLE;
2616
goto end;
2617
}
2618
2619
sigemptyset(&sigterm_action.sa_mask);
2620
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2621
if(ret == -1){
2622
perror_plus("sigaddset");
2623
exitcode = EX_OSERR;
2624
goto end;
2625
}
2626
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2627
if(ret == -1){
2628
perror_plus("sigaddset");
2629
exitcode = EX_OSERR;
2630
goto end;
2631
}
2632
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2633
if(ret == -1){
2634
perror_plus("sigaddset");
2635
exitcode = EX_OSERR;
2636
goto end;
2637
}
2638
/* Need to check if the handler is SIG_IGN before handling:
2639
| [[info:libc:Initial Signal Actions]] |
2640
| [[info:libc:Basic Signal Handling]] |
2641
*/
2642
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2643
if(ret == -1){
2644
perror_plus("sigaction");
2645
return EX_OSERR;
2646
}
2647
if(old_sigterm_action.sa_handler != SIG_IGN){
2648
ret = sigaction(SIGINT, &sigterm_action, NULL);
2649
if(ret == -1){
2650
perror_plus("sigaction");
2651
exitcode = EX_OSERR;
2652
goto end;
2653
}
2654
}
2655
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2656
if(ret == -1){
2657
perror_plus("sigaction");
2658
return EX_OSERR;
2659
}
2660
if(old_sigterm_action.sa_handler != SIG_IGN){
2661
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2662
if(ret == -1){
2663
perror_plus("sigaction");
2664
exitcode = EX_OSERR;
2665
goto end;
2666
}
2667
}
2668
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2669
if(ret == -1){
2670
perror_plus("sigaction");
2671
return EX_OSERR;
2672
}
2673
if(old_sigterm_action.sa_handler != SIG_IGN){
2674
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2675
if(ret == -1){
2676
perror_plus("sigaction");
2677
exitcode = EX_OSERR;
2678
goto end;
2679
}
2680
}
2681
2682
/* If no interfaces were specified, make a list */
2683
if(mc.interfaces == NULL){
2684
struct dirent **direntries = NULL;
2685
/* Look for any good interfaces */
2686
ret = scandir(sys_class_net, &direntries, good_interface,
2687
alphasort);
2688
if(ret >= 1){
2689
/* Add all found interfaces to interfaces list */
2690
for(int i = 0; i < ret; ++i){
2691
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2692
direntries[i]->d_name);
2693
if(ret_errno != 0){
2694
errno = ret_errno;
2695
perror_plus("argz_add");
2696
free(direntries[i]);
2697
continue;
2698
}
2699
if(debug){
2700
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2701
direntries[i]->d_name);
2702
}
2703
free(direntries[i]);
2704
}
2705
free(direntries);
2706
} else {
2707
if(ret == 0){
2708
free(direntries);
2709
}
2710
fprintf_plus(stderr, "Could not find a network interface\n");
2711
exitcode = EXIT_FAILURE;
2712
goto end;
2713
}
2714
}
2715
2716
/* Bring up interfaces which are down, and remove any "none"s */
2717
{
2718
char *interface = NULL;
2719
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2720
interface))){
2721
/* If interface name is "none", stop bringing up interfaces.
2722
Also remove all instances of "none" from the list */
2723
if(strcmp(interface, "none") == 0){
2724
argz_delete(&mc.interfaces, &mc.interfaces_size,
2725
interface);
2726
interface = NULL;
2727
while((interface = argz_next(mc.interfaces,
2728
mc.interfaces_size, interface))){
2729
if(strcmp(interface, "none") == 0){
2730
argz_delete(&mc.interfaces, &mc.interfaces_size,
2731
interface);
2732
interface = NULL;
2733
}
2734
}
2735
break;
2736
}
2737
bool interface_was_up = interface_is_up(interface);
2738
errno = bring_up_interface(interface, delay);
2739
if(not interface_was_up){
2740
if(errno != 0){
2741
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2742
" %s\n", interface, strerror(errno));
2743
} else {
2744
errno = argz_add(&interfaces_to_take_down,
2745
&interfaces_to_take_down_size,
2746
interface);
2747
if(errno != 0){
2748
perror_plus("argz_add");
2749
}
2750
}
2751
}
2752
}
2753
if(debug and (interfaces_to_take_down == NULL)){
2754
fprintf_plus(stderr, "No interfaces were brought up\n");
2755
}
2756
}
2757
2758
/* If we only got one interface, explicitly use only that one */
2759
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
1089
2760
if(debug){
1090
fprintf(stderr, "Starting Avahi loop search\n");
1091
}
1092
1093
avahi_simple_poll_loop(mc.simple_poll);
1094
2761
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2762
mc.interfaces);
2763
}
2764
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2765
}
2766
2767
if(quit_now){
2768
goto end;
2769
}
2770
2771
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2772
if(ret == -1){
2773
fprintf_plus(stderr, "init_gnutls_global failed\n");
2774
exitcode = EX_UNAVAILABLE;
2775
goto end;
2776
} else {
2777
gnutls_initialized = true;
2778
}
2779
2780
if(quit_now){
2781
goto end;
2782
}
2783
2784
/* Try /run/tmp before /tmp */
2785
tempdir = mkdtemp(run_tempdir);
2786
if(tempdir == NULL and errno == ENOENT){
2787
if(debug){
2788
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2789
run_tempdir, old_tempdir);
2790
}
2791
tempdir = mkdtemp(old_tempdir);
2792
}
2793
if(tempdir == NULL){
2794
perror_plus("mkdtemp");
2795
goto end;
2796
}
2797
2798
if(quit_now){
2799
goto end;
2800
}
2801
2802
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2803
fprintf_plus(stderr, "init_gpgme failed\n");
2804
exitcode = EX_UNAVAILABLE;
2805
goto end;
2806
} else {
2807
gpgme_initialized = true;
2808
}
2809
2810
if(quit_now){
2811
goto end;
2812
}
2813
2814
if(connect_to != NULL){
2815
/* Connect directly, do not use Zeroconf */
2816
/* (Mainly meant for debugging) */
2817
char *address = strrchr(connect_to, ':');
2818
2819
if(address == NULL){
2820
fprintf_plus(stderr, "No colon in address\n");
2821
exitcode = EX_USAGE;
2822
goto end;
2823
}
2824
2825
if(quit_now){
2826
goto end;
2827
}
2828
2829
in_port_t port;
2830
errno = 0;
2831
tmpmax = strtoimax(address+1, &tmp, 10);
2832
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2833
or tmpmax != (in_port_t)tmpmax){
2834
fprintf_plus(stderr, "Bad port number\n");
2835
exitcode = EX_USAGE;
2836
goto end;
2837
}
2838
2839
if(quit_now){
2840
goto end;
2841
}
2842
2843
port = (in_port_t)tmpmax;
2844
*address = '\0';
2845
/* Colon in address indicates IPv6 */
2846
int af;
2847
if(strchr(connect_to, ':') != NULL){
2848
af = AF_INET6;
2849
/* Accept [] around IPv6 address - see RFC 5952 */
2850
if(connect_to[0] == '[' and address[-1] == ']')
2851
{
2852
connect_to++;
2853
address[-1] = '\0';
2854
}
2855
} else {
2856
af = AF_INET;
2857
}
2858
address = connect_to;
2859
2860
if(quit_now){
2861
goto end;
2862
}
2863
2864
while(not quit_now){
2865
ret = start_mandos_communication(address, port, if_index, af,
2866
&mc);
2867
if(quit_now or ret == 0){
2868
break;
2869
}
2870
if(debug){
2871
fprintf_plus(stderr, "Retrying in %d seconds\n",
2872
(int)retry_interval);
2873
}
2874
sleep((unsigned int)retry_interval);
2875
}
2876
2877
if(not quit_now){
2878
exitcode = EXIT_SUCCESS;
2879
}
2880
2881
goto end;
2882
}
2883
2884
if(quit_now){
2885
goto end;
2886
}
2887
2888
{
2889
AvahiServerConfig config;
2890
/* Do not publish any local Zeroconf records */
2891
avahi_server_config_init(&config);
2892
config.publish_hinfo = 0;
2893
config.publish_addresses = 0;
2894
config.publish_workstation = 0;
2895
config.publish_domain = 0;
2896
2897
/* Allocate a new server */
2898
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2899
&config, NULL, NULL, &ret);
2900
2901
/* Free the Avahi configuration data */
2902
avahi_server_config_free(&config);
2903
}
2904
2905
/* Check if creating the Avahi server object succeeded */
2906
if(mc.server == NULL){
2907
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2908
avahi_strerror(ret));
2909
exitcode = EX_UNAVAILABLE;
2910
goto end;
2911
}
2912
2913
if(quit_now){
2914
goto end;
2915
}
2916
2917
/* Create the Avahi service browser */
2918
sb = avahi_s_service_browser_new(mc.server, if_index,
2919
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2920
NULL, 0, browse_callback,
2921
(void *)&mc);
2922
if(sb == NULL){
2923
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2924
avahi_strerror(avahi_server_errno(mc.server)));
2925
exitcode = EX_UNAVAILABLE;
2926
goto end;
2927
}
2928
2929
if(quit_now){
2930
goto end;
2931
}
2932
2933
/* Run the main loop */
2934
2935
if(debug){
2936
fprintf_plus(stderr, "Starting Avahi loop search\n");
2937
}
2938
2939
ret = avahi_loop_with_timeout(simple_poll,
2940
(int)(retry_interval * 1000), &mc);
2941
if(debug){
2942
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2943
(ret == 0) ? "successfully" : "with error");
2944
}
2945
1095
2946
end:
1096
1097
if(debug){
1098
fprintf(stderr, "%s exiting\n", argv[0]);
1099
}
1100
1101
/* Cleanup things */
1102
if(sb != NULL)
1103
avahi_s_service_browser_free(sb);
1104
1105
if(mc.server != NULL)
1106
avahi_server_free(mc.server);
1107
1108
if(mc.simple_poll != NULL)
1109
avahi_simple_poll_free(mc.simple_poll);
1110
1111
if(gnutls_initialized){
1112
gnutls_certificate_free_credentials(mc.cred);
1113
gnutls_global_deinit();
1114
gnutls_dh_params_deinit(mc.dh_params);
1115
}
1116
1117
if(gpgme_initialized){
1118
gpgme_release(mc.ctx);
1119
}
1120
1121
/* Removes the temp directory used by GPGME */
1122
if(tempdir_created){
1123
DIR *d;
1124
struct dirent *direntry;
1125
d = opendir(tempdir);
1126
if(d == NULL){
1127
if(errno != ENOENT){
1128
perror("opendir");
1129
}
1130
} else {
1131
while(true){
1132
direntry = readdir(d);
1133
if(direntry == NULL){
1134
break;
1135
}
1136
/* Skip "." and ".." */
1137
if(direntry->d_name[0] == '.'
1138
and (direntry->d_name[1] == '\0'
1139
or (direntry->d_name[1] == '.'
1140
and direntry->d_name[2] == '\0'))){
1141
continue;
1142
}
1143
char *fullname = NULL;
1144
ret = asprintf(&fullname, "%s/%s", tempdir,
1145
direntry->d_name);
1146
if(ret < 0){
1147
perror("asprintf");
1148
continue;
1149
}
1150
ret = remove(fullname);
1151
if(ret == -1){
1152
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1153
strerror(errno));
1154
}
1155
free(fullname);
1156
}
1157
closedir(d);
1158
}
1159
ret = rmdir(tempdir);
1160
if(ret == -1 and errno != ENOENT){
1161
perror("rmdir");
1162
}
1163
}
1164
1165
return exitcode;
2947
2948
if(debug){
2949
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2950
}
2951
2952
/* Cleanup things */
2953
free(mc.interfaces);
2954
2955
if(sb != NULL)
2956
avahi_s_service_browser_free(sb);
2957
2958
if(mc.server != NULL)
2959
avahi_server_free(mc.server);
2960
2961
if(simple_poll != NULL)
2962
avahi_simple_poll_free(simple_poll);
2963
2964
if(gnutls_initialized){
2965
gnutls_certificate_free_credentials(mc.cred);
2966
gnutls_dh_params_deinit(mc.dh_params);
2967
}
2968
2969
if(gpgme_initialized){
2970
gpgme_release(mc.ctx);
2971
}
2972
2973
/* Cleans up the circular linked list of Mandos servers the client
2974
has seen */
2975
if(mc.current_server != NULL){
2976
mc.current_server->prev->next = NULL;
2977
while(mc.current_server != NULL){
2978
server *next = mc.current_server->next;
2979
#ifdef __GNUC__
2980
#pragma GCC diagnostic push
2981
#pragma GCC diagnostic ignored "-Wcast-qual"
2982
#endif
2983
free((char *)(mc.current_server->ip));
2984
#ifdef __GNUC__
2985
#pragma GCC diagnostic pop
2986
#endif
2987
free(mc.current_server);
2988
mc.current_server = next;
2989
}
2990
}
2991
2992
/* Re-raise privileges */
2993
{
2994
ret = raise_privileges();
2995
if(ret != 0){
2996
errno = ret;
2997
perror_plus("Failed to raise privileges");
2998
} else {
2999
3000
/* Run network hooks */
3001
run_network_hooks("stop", interfaces_hooks != NULL ?
3002
interfaces_hooks : "", delay);
3003
3004
/* Take down the network interfaces which were brought up */
3005
{
3006
char *interface = NULL;
3007
while((interface=argz_next(interfaces_to_take_down,
3008
interfaces_to_take_down_size,
3009
interface))){
3010
ret = take_down_interface(interface);
3011
if(ret != 0){
3012
errno = ret;
3013
perror_plus("Failed to take down interface");
3014
}
3015
}
3016
if(debug and (interfaces_to_take_down == NULL)){
3017
fprintf_plus(stderr, "No interfaces needed to be taken"
3018
" down\n");
3019
}
3020
}
3021
}
3022
3023
ret = lower_privileges_permanently();
3024
if(ret != 0){
3025
errno = ret;
3026
perror_plus("Failed to lower privileges permanently");
3027
}
3028
}
3029
3030
free(interfaces_to_take_down);
3031
free(interfaces_hooks);
3032
3033
void clean_dir_at(int base, const char * const dirname,
3034
uintmax_t level){
3035
struct dirent **direntries = NULL;
3036
int dret;
3037
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3038
O_RDONLY
3039
| O_NOFOLLOW
3040
| O_DIRECTORY
3041
| O_PATH));
3042
if(dir_fd == -1){
3043
perror_plus("open");
3044
}
3045
int numentries = scandirat(dir_fd, ".", &direntries,
3046
notdotentries, alphasort);
3047
if(numentries >= 0){
3048
for(int i = 0; i < numentries; i++){
3049
if(debug){
3050
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3051
dirname, direntries[i]->d_name);
3052
}
3053
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3054
if(dret == -1){
3055
if(errno == EISDIR){
3056
dret = unlinkat(dir_fd, direntries[i]->d_name,
3057
AT_REMOVEDIR);
3058
}
3059
if((dret == -1) and (errno == ENOTEMPTY)
3060
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3061
== 0) and (level == 0)){
3062
/* Recurse only in this special case */
3063
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3064
dret = 0;
3065
}
3066
if(dret == -1){
3067
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3068
direntries[i]->d_name, strerror(errno));
3069
}
3070
}
3071
free(direntries[i]);
3072
}
3073
3074
/* need to clean even if 0 because man page doesn't specify */
3075
free(direntries);
3076
if(numentries == -1){
3077
perror_plus("scandirat");
3078
}
3079
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3080
if(dret == -1 and errno != ENOENT){
3081
perror_plus("rmdir");
3082
}
3083
} else {
3084
perror_plus("scandirat");
3085
}
3086
close(dir_fd);
3087
}
3088
3089
/* Removes the GPGME temp directory and all files inside */
3090
if(tempdir != NULL){
3091
clean_dir_at(-1, tempdir, 0);
3092
}
3093
3094
if(quit_now){
3095
sigemptyset(&old_sigterm_action.sa_mask);
3096
old_sigterm_action.sa_handler = SIG_DFL;
3097
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3098
&old_sigterm_action,
3099
NULL));
3100
if(ret == -1){
3101
perror_plus("sigaction");
3102
}
3103
do {
3104
ret = raise(signal_received);
3105
} while(ret != 0 and errno == EINTR);
3106
if(ret != 0){
3107
perror_plus("raise");
3108
abort();
3109
}
3110
TEMP_FAILURE_RETRY(pause());
3111
}
3112
3113
return exitcode;
1166
3114
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0