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237.7.381
(compared to revision 237.2.38)
: plugins.d/mandos-client.c
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- Committer: Teddy Hogeborn
- Date: 2016-03-17 20:40:55 UTC
- mto: (237.7.594 trunk)
- mto: This revision was merged to the branch mainline in revision 341.
- 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
#include <stdint.h> /* uint16_t, uint32_t */
43
stdout, ferror() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
41
45
#include <stddef.h> /* NULL, size_t, ssize_t */
42
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
43
srand() */
44
#include <stdbool.h> /* bool, true */
45
#include <string.h> /* memset(), strcmp(), strlen(),
46
strerror(), asprintf(), strcpy() */
47
#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 */
48
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
49
53
sockaddr_in6, PF_INET6,
50
SOCK_STREAM, INET6_ADDRSTRLEN,
51
uid_t, gid_t, open(), opendir(),
52
DIR */
53
#include <sys/stat.h> /* open() */
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open(), S_ISREG */
54
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
55
struct in6_addr, inet_pton(),
56
connect() */
57
#include <fcntl.h> /* open() */
58
inet_pton(), connect(),
59
getnameinfo() */
60
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
58
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
59
62
*/
60
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
61
#include <assert.h> /* assert() */
62
#include <errno.h> /* perror(), errno */
63
#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() */
64
72
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
65
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SIOCSIFFLAGS, if_indextoname(),
66
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if_nametoindex(), IF_NAMESIZE */
67
#include <netinet/in.h>
75
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
76
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
77
*/
68
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#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
69
getuid(), getgid(), setuid(),
70
setgid() */
71
#include <arpa/inet.h> /* inet_pton(), htons */
72
#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 */
73
84
#include <argp.h> /* struct argp_option, error_t, struct
74
85
argp_state, struct argp,
75
86
argp_parse(), ARGP_KEY_ARG,
76
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__ */
77
106
78
107
/* Avahi */
79
108
/* All Avahi types, constants and functions
93
122
init_gnutls_session(),
94
123
GNUTLS_* */
95
124
#include <gnutls/openpgp.h>
96
/* gnutls_certificate_set_openpgp_key_file(),
97
GNUTLS_OPENPGP_FMT_BASE64 */
125
/* gnutls_certificate_set_openpgp_key_file(),
126
GNUTLS_OPENPGP_FMT_BASE64 */
98
127
99
128
/* GPGME */
100
129
#include <gpgme.h> /* All GPGME types, constants and
108
137
#define PATHDIR "/conf/conf.d/mandos"
109
138
#define SECKEY "seckey.txt"
110
139
#define PUBKEY "pubkey.txt"
140
#define HOOKDIR "/lib/mandos/network-hooks.d"
111
141
112
142
bool debug = false;
113
143
static const char mandos_protocol_version[] = "1";
114
144
const char *argp_program_version = "mandos-client " VERSION;
115
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;
116
163
117
164
/* Used for passing in values through the Avahi callback functions */
118
165
typedef struct {
119
AvahiSimplePoll *simple_poll;
120
166
AvahiServer *server;
121
167
gnutls_certificate_credentials_t cred;
122
168
unsigned int dh_bits;
123
169
gnutls_dh_params_t dh_params;
124
170
const char *priority;
125
171
gpgme_ctx_t ctx;
172
server *current_server;
173
char *interfaces;
174
size_t interfaces_size;
126
175
} mandos_context;
127
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
128
202
/*
129
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
130
* "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,
131
205
* "buffer_length" is how much is already used.
132
206
*/
133
size_t adjustbuffer(char **buffer, size_t buffer_length,
134
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){
135
210
if(buffer_length + BUFFER_SIZE > buffer_capacity){
136
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
137
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;
138
217
return 0;
139
218
}
219
*buffer = new_buf;
140
220
buffer_capacity += BUFFER_SIZE;
141
221
}
142
222
return buffer_capacity;
143
223
}
144
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
145
273
/*
146
274
* Initialize GPGME.
147
275
*/
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
149
const char *pubkey, const char *tempdir){
150
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){
151
281
gpgme_error_t rc;
152
282
gpgme_engine_info_t engine_info;
153
283
154
155
284
/*
156
* Helper function to insert pub and seckey to the enigne keyring.
285
* Helper function to insert pub and seckey to the engine keyring.
157
286
*/
158
bool import_key(const char *filename){
287
bool import_key(const char * const filename){
288
int ret;
159
289
int fd;
160
290
gpgme_data_t pgp_data;
161
291
162
292
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
163
293
if(fd == -1){
164
perror("open");
294
perror_plus("open");
165
295
return false;
166
296
}
167
297
168
298
rc = gpgme_data_new_from_fd(&pgp_data, fd);
169
299
if(rc != GPG_ERR_NO_ERROR){
170
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
171
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));
172
302
return false;
173
303
}
174
304
175
305
rc = gpgme_op_import(mc->ctx, pgp_data);
176
306
if(rc != GPG_ERR_NO_ERROR){
177
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
178
gpgme_strsource(rc), gpgme_strerror(rc));
307
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
179
309
return false;
180
310
}
181
311
182
ret = (int)TEMP_FAILURE_RETRY(close(fd));
312
ret = close(fd);
183
313
if(ret == -1){
184
perror("close");
314
perror_plus("close");
185
315
}
186
316
gpgme_data_release(pgp_data);
187
317
return true;
188
318
}
189
319
190
320
if(debug){
191
fprintf(stderr, "Initialize gpgme\n");
321
fprintf_plus(stderr, "Initializing GPGME\n");
192
322
}
193
323
194
324
/* Init GPGME */
195
325
gpgme_check_version(NULL);
196
326
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
197
327
if(rc != GPG_ERR_NO_ERROR){
198
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
199
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));
200
330
return false;
201
331
}
202
332
203
/* Set GPGME home directory for the OpenPGP engine only */
333
/* Set GPGME home directory for the OpenPGP engine only */
204
334
rc = gpgme_get_engine_info(&engine_info);
205
335
if(rc != GPG_ERR_NO_ERROR){
206
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
207
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));
208
338
return false;
209
339
}
210
340
while(engine_info != NULL){
216
346
engine_info = engine_info->next;
217
347
}
218
348
if(engine_info == NULL){
219
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);
220
351
return false;
221
352
}
222
353
223
354
/* Create new GPGME "context" */
224
355
rc = gpgme_new(&(mc->ctx));
225
356
if(rc != GPG_ERR_NO_ERROR){
226
fprintf(stderr, "bad gpgme_new: %s: %s\n",
227
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));
228
360
return false;
229
361
}
230
362
232
364
return false;
233
365
}
234
366
235
return true;
367
return true;
236
368
}
237
369
238
370
/*
239
371
* Decrypt OpenPGP data.
240
372
* Returns -1 on error
241
373
*/
242
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
243
const char *cryptotext,
374
__attribute__((nonnull, warn_unused_result))
375
static ssize_t pgp_packet_decrypt(const char *cryptotext,
244
376
size_t crypto_size,
245
char **plaintext){
377
char **plaintext,
378
mandos_context *mc){
246
379
gpgme_data_t dh_crypto, dh_plain;
247
380
gpgme_error_t rc;
248
381
ssize_t ret;
250
383
ssize_t plaintext_length = 0;
251
384
252
385
if(debug){
253
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
386
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
254
387
}
255
388
256
389
/* Create new GPGME data buffer from memory cryptotext */
257
390
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
258
391
0);
259
392
if(rc != GPG_ERR_NO_ERROR){
260
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
261
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));
262
395
return -1;
263
396
}
264
397
265
398
/* Create new empty GPGME data buffer for the plaintext */
266
399
rc = gpgme_data_new(&dh_plain);
267
400
if(rc != GPG_ERR_NO_ERROR){
268
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
269
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));
270
404
gpgme_data_release(dh_crypto);
271
405
return -1;
272
406
}
275
409
data buffer */
276
410
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
277
411
if(rc != GPG_ERR_NO_ERROR){
278
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
412
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
280
414
plaintext_length = -1;
281
415
if(debug){
282
416
gpgme_decrypt_result_t result;
283
417
result = gpgme_op_decrypt_result(mc->ctx);
284
418
if(result == NULL){
285
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
419
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
286
420
} else {
287
fprintf(stderr, "Unsupported algorithm: %s\n",
288
result->unsupported_algorithm);
289
fprintf(stderr, "Wrong key usage: %u\n",
290
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);
291
425
if(result->file_name != NULL){
292
fprintf(stderr, "File name: %s\n", result->file_name);
426
fprintf_plus(stderr, "File name: %s\n", result->file_name);
293
427
}
294
428
gpgme_recipient_t recipient;
295
429
recipient = result->recipients;
296
if(recipient){
297
while(recipient != NULL){
298
fprintf(stderr, "Public key algorithm: %s\n",
299
gpgme_pubkey_algo_name(recipient->pubkey_algo));
300
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
301
fprintf(stderr, "Secret key available: %s\n",
302
recipient->status == GPG_ERR_NO_SECKEY
303
? "No" : "Yes");
304
recipient = recipient->next;
305
}
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;
306
439
}
307
440
}
308
441
}
310
443
}
311
444
312
445
if(debug){
313
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
446
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
314
447
}
315
448
316
449
/* Seek back to the beginning of the GPGME plaintext data buffer */
317
450
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
318
perror("gpgme_data_seek");
451
perror_plus("gpgme_data_seek");
319
452
plaintext_length = -1;
320
453
goto decrypt_end;
321
454
}
322
455
323
456
*plaintext = NULL;
324
457
while(true){
325
plaintext_capacity = adjustbuffer(plaintext,
326
(size_t)plaintext_length,
327
plaintext_capacity);
458
plaintext_capacity = incbuffer(plaintext,
459
(size_t)plaintext_length,
460
plaintext_capacity);
328
461
if(plaintext_capacity == 0){
329
perror("adjustbuffer");
330
plaintext_length = -1;
331
goto decrypt_end;
462
perror_plus("incbuffer");
463
plaintext_length = -1;
464
goto decrypt_end;
332
465
}
333
466
334
467
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
339
472
break;
340
473
}
341
474
if(ret < 0){
342
perror("gpgme_data_read");
475
perror_plus("gpgme_data_read");
343
476
plaintext_length = -1;
344
477
goto decrypt_end;
345
478
}
347
480
}
348
481
349
482
if(debug){
350
fprintf(stderr, "Decrypted password is: ");
483
fprintf_plus(stderr, "Decrypted password is: ");
351
484
for(ssize_t i = 0; i < plaintext_length; i++){
352
485
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
353
486
}
364
497
return plaintext_length;
365
498
}
366
499
367
static const char * safer_gnutls_strerror(int value) {
368
const char *ret = gnutls_strerror(value); /* Spurious warning from
369
-Wunreachable-code */
370
if(ret == NULL)
371
ret = "(unknown)";
372
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);
373
511
}
374
512
375
513
/* GnuTLS log function callback */
514
__attribute__((nonnull))
376
515
static void debuggnutls(__attribute__((unused)) int level,
377
516
const char* string){
378
fprintf(stderr, "GnuTLS: %s", string);
517
fprintf_plus(stderr, "GnuTLS: %s", string);
379
518
}
380
519
381
static int init_gnutls_global(mandos_context *mc,
382
const char *pubkeyfilename,
383
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){
384
525
int ret;
526
unsigned int uret;
385
527
386
528
if(debug){
387
fprintf(stderr, "Initializing GnuTLS\n");
388
}
389
390
ret = gnutls_global_init();
391
if(ret != GNUTLS_E_SUCCESS) {
392
fprintf(stderr, "GnuTLS global_init: %s\n",
393
safer_gnutls_strerror(ret));
394
return -1;
529
fprintf_plus(stderr, "Initializing GnuTLS\n");
395
530
}
396
531
397
532
if(debug){
403
538
}
404
539
405
540
/* OpenPGP credentials */
406
gnutls_certificate_allocate_credentials(&mc->cred);
541
ret = gnutls_certificate_allocate_credentials(&mc->cred);
407
542
if(ret != GNUTLS_E_SUCCESS){
408
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
409
* from
410
* -Wunreachable-code
411
*/
412
safer_gnutls_strerror(ret));
413
gnutls_global_deinit();
543
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
544
safer_gnutls_strerror(ret));
414
545
return -1;
415
546
}
416
547
417
548
if(debug){
418
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
419
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
420
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);
421
553
}
422
554
423
555
ret = gnutls_certificate_set_openpgp_key_file
424
556
(mc->cred, pubkeyfilename, seckeyfilename,
425
557
GNUTLS_OPENPGP_FMT_BASE64);
426
if(ret != GNUTLS_E_SUCCESS) {
427
fprintf(stderr,
428
"Error[%d] while reading the OpenPGP key pair ('%s',"
429
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
430
fprintf(stderr, "The GnuTLS error is: %s\n",
431
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));
432
564
goto globalfail;
433
565
}
434
566
435
567
/* GnuTLS server initialization */
436
568
ret = gnutls_dh_params_init(&mc->dh_params);
437
if(ret != GNUTLS_E_SUCCESS) {
438
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
439
" %s\n", safer_gnutls_strerror(ret));
440
goto globalfail;
441
}
442
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
443
if(ret != GNUTLS_E_SUCCESS) {
444
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
445
safer_gnutls_strerror(ret));
446
goto globalfail;
447
}
448
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
}
449
747
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
450
748
451
749
return 0;
453
751
globalfail:
454
752
455
753
gnutls_certificate_free_credentials(mc->cred);
456
gnutls_global_deinit();
457
754
gnutls_dh_params_deinit(mc->dh_params);
458
755
return -1;
459
756
}
460
757
461
static int init_gnutls_session(mandos_context *mc,
462
gnutls_session_t *session){
758
__attribute__((nonnull, warn_unused_result))
759
static int init_gnutls_session(gnutls_session_t *session,
760
mandos_context *mc){
463
761
int ret;
464
762
/* GnuTLS session creation */
465
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);
466
769
if(ret != GNUTLS_E_SUCCESS){
467
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
468
safer_gnutls_strerror(ret));
770
fprintf_plus(stderr,
771
"Error in GnuTLS session initialization: %s\n",
772
safer_gnutls_strerror(ret));
469
773
}
470
774
471
775
{
472
776
const char *err;
473
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
474
if(ret != GNUTLS_E_SUCCESS) {
475
fprintf(stderr, "Syntax error at: %s\n", err);
476
fprintf(stderr, "GnuTLS error: %s\n",
477
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));
478
788
gnutls_deinit(*session);
479
789
return -1;
480
790
}
481
791
}
482
792
483
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
484
mc->cred);
485
if(ret != GNUTLS_E_SUCCESS) {
486
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
487
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));
488
804
gnutls_deinit(*session);
489
805
return -1;
490
806
}
491
807
492
808
/* ignore client certificate if any. */
493
gnutls_certificate_server_set_request(*session,
494
GNUTLS_CERT_IGNORE);
495
496
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
809
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
497
810
498
811
return 0;
499
812
}
502
815
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
503
816
__attribute__((unused)) const char *txt){}
504
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
505
1036
/* Called when a Mandos server is found */
506
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,
507
1039
AvahiIfIndex if_index,
508
mandos_context *mc){
509
int ret, tcp_sd;
1040
int af, mandos_context *mc){
1041
int ret, tcp_sd = -1;
510
1042
ssize_t sret;
511
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1043
struct sockaddr_storage to;
512
1044
char *buffer = NULL;
513
char *decrypted_buffer;
1045
char *decrypted_buffer = NULL;
514
1046
size_t buffer_length = 0;
515
1047
size_t buffer_capacity = 0;
516
ssize_t decrypted_buffer_size;
517
1048
size_t written;
518
int retval = 0;
519
char interface[IF_NAMESIZE];
1049
int retval = -1;
520
1050
gnutls_session_t session;
521
522
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);
523
1107
if(ret != 0){
524
1108
return -1;
525
1109
}
526
1110
527
1111
if(debug){
528
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
529
"\n", ip, port);
530
}
531
532
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
533
if(tcp_sd < 0) {
534
perror("socket");
535
return -1;
536
}
537
538
if(debug){
539
if(if_indextoname((unsigned int)if_index, interface) == NULL){
540
perror("if_indextoname");
541
return -1;
542
}
543
fprintf(stderr, "Binding to interface %s\n", interface);
544
}
545
546
memset(&to, 0, sizeof(to));
547
to.in6.sin6_family = AF_INET6;
548
/* It would be nice to have a way to detect if we were passed an
549
IPv4 address here. Now we assume an IPv6 address. */
550
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
}
551
1138
if(ret < 0 ){
552
perror("inet_pton");
553
return -1;
1139
int e = errno;
1140
perror_plus("inet_pton");
1141
errno = e;
1142
goto mandos_end;
554
1143
}
555
1144
if(ret == 0){
556
fprintf(stderr, "Bad address: %s\n", ip);
557
return -1;
558
}
559
to.in6.sin6_port = htons(port); /* Spurious warnings from
560
-Wconversion and
561
-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
}
562
1166
563
to.in6.sin6_scope_id = (uint32_t)if_index;
1167
if(quit_now){
1168
errno = EINTR;
1169
goto mandos_end;
1170
}
564
1171
565
1172
if(debug){
566
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
567
port);
568
char addrstr[INET6_ADDRSTRLEN] = "";
569
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
570
sizeof(addrstr)) == NULL){
571
perror("inet_ntop");
572
} else {
573
if(strcmp(addrstr, ip) != 0){
574
fprintf(stderr, "Canonical address form: %s\n", addrstr);
575
}
576
}
577
}
578
579
ret = connect(tcp_sd, &to.in, sizeof(to));
580
if(ret < 0){
581
perror("connect");
582
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;
583
1267
}
584
1268
585
1269
const char *out = mandos_protocol_version;
587
1271
while(true){
588
1272
size_t out_size = strlen(out);
589
1273
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
590
out_size - written));
1274
out_size - written));
591
1275
if(ret == -1){
592
perror("write");
593
retval = -1;
1276
int e = errno;
1277
perror_plus("write");
1278
errno = e;
594
1279
goto mandos_end;
595
1280
}
596
1281
written += (size_t)ret;
604
1289
break;
605
1290
}
606
1291
}
1292
1293
if(quit_now){
1294
errno = EINTR;
1295
goto mandos_end;
1296
}
607
1297
}
608
1298
609
1299
if(debug){
610
fprintf(stderr, "Establishing TLS session with %s\n", ip);
611
}
612
613
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
614
615
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 {
616
1320
ret = gnutls_handshake(session);
1321
if(quit_now){
1322
errno = EINTR;
1323
goto mandos_end;
1324
}
617
1325
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
618
1326
619
1327
if(ret != GNUTLS_E_SUCCESS){
620
1328
if(debug){
621
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1329
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
622
1330
gnutls_perror(ret);
623
1331
}
624
retval = -1;
1332
errno = EPROTO;
625
1333
goto mandos_end;
626
1334
}
627
1335
628
1336
/* Read OpenPGP packet that contains the wanted password */
629
1337
630
1338
if(debug){
631
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
632
ip);
1339
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1340
" %s\n", ip);
633
1341
}
634
1342
635
1343
while(true){
636
buffer_capacity = adjustbuffer(&buffer, buffer_length,
637
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);
638
1352
if(buffer_capacity == 0){
639
perror("adjustbuffer");
640
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;
641
1361
goto mandos_end;
642
1362
}
643
1363
652
1372
case GNUTLS_E_AGAIN:
653
1373
break;
654
1374
case GNUTLS_E_REHANDSHAKE:
655
do{
1375
do {
656
1376
ret = gnutls_handshake(session);
1377
1378
if(quit_now){
1379
errno = EINTR;
1380
goto mandos_end;
1381
}
657
1382
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
658
1383
if(ret < 0){
659
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1384
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1385
"***\n");
660
1386
gnutls_perror(ret);
661
retval = -1;
1387
errno = EPROTO;
662
1388
goto mandos_end;
663
1389
}
664
1390
break;
665
1391
default:
666
fprintf(stderr, "Unknown error while reading data from"
667
" encrypted session with Mandos server\n");
668
retval = -1;
1392
fprintf_plus(stderr, "Unknown error while reading data from"
1393
" encrypted session with Mandos server\n");
669
1394
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1395
errno = EIO;
670
1396
goto mandos_end;
671
1397
}
672
1398
} else {
675
1401
}
676
1402
677
1403
if(debug){
678
fprintf(stderr, "Closing TLS session\n");
679
}
680
681
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);
682
1419
683
1420
if(buffer_length > 0){
684
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
685
buffer_length,
686
&decrypted_buffer);
1421
ssize_t decrypted_buffer_size;
1422
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1423
&decrypted_buffer, mc);
687
1424
if(decrypted_buffer_size >= 0){
1425
688
1426
written = 0;
689
1427
while(written < (size_t) decrypted_buffer_size){
1428
if(quit_now){
1429
errno = EINTR;
1430
goto mandos_end;
1431
}
1432
690
1433
ret = (int)fwrite(decrypted_buffer + written, 1,
691
1434
(size_t)decrypted_buffer_size - written,
692
1435
stdout);
693
1436
if(ret == 0 and ferror(stdout)){
1437
int e = errno;
694
1438
if(debug){
695
fprintf(stderr, "Error writing encrypted data: %s\n",
696
strerror(errno));
1439
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1440
strerror(errno));
697
1441
}
698
retval = -1;
699
break;
1442
errno = e;
1443
goto mandos_end;
700
1444
}
701
1445
written += (size_t)ret;
702
1446
}
703
free(decrypted_buffer);
704
} else {
705
retval = -1;
1447
retval = 0;
706
1448
}
707
} else {
708
retval = -1;
709
1449
}
710
1450
711
1451
/* Shutdown procedure */
712
1452
713
1453
mandos_end:
714
free(buffer);
715
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
716
if(ret == -1){
717
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
}
718
1479
}
719
gnutls_deinit(session);
720
1480
return retval;
721
1481
}
722
1482
1483
__attribute__((nonnull))
723
1484
static void resolve_callback(AvahiSServiceResolver *r,
724
1485
AvahiIfIndex interface,
725
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1486
AvahiProtocol proto,
726
1487
AvahiResolverEvent event,
727
1488
const char *name,
728
1489
const char *type,
733
1494
AVAHI_GCC_UNUSED AvahiStringList *txt,
734
1495
AVAHI_GCC_UNUSED AvahiLookupResultFlags
735
1496
flags,
736
void* userdata) {
737
mandos_context *mc = userdata;
738
assert(r);
1497
void *mc){
1498
if(r == NULL){
1499
return;
1500
}
739
1501
740
1502
/* Called whenever a service has been resolved successfully or
741
1503
timed out */
742
1504
743
switch(event) {
1505
if(quit_now){
1506
avahi_s_service_resolver_free(r);
1507
return;
1508
}
1509
1510
switch(event){
744
1511
default:
745
1512
case AVAHI_RESOLVER_FAILURE:
746
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
747
" of type '%s' in domain '%s': %s\n", name, type, domain,
748
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)));
749
1518
break;
750
1519
751
1520
case AVAHI_RESOLVER_FOUND:
753
1522
char ip[AVAHI_ADDRESS_STR_MAX];
754
1523
avahi_address_snprint(ip, sizeof(ip), address);
755
1524
if(debug){
756
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
757
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
758
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);
759
1528
}
760
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);
761
1533
if(ret == 0){
762
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
}
763
1542
}
764
1543
}
765
1544
}
766
1545
avahi_s_service_resolver_free(r);
767
1546
}
768
1547
769
static void browse_callback( AvahiSServiceBrowser *b,
770
AvahiIfIndex interface,
771
AvahiProtocol protocol,
772
AvahiBrowserEvent event,
773
const char *name,
774
const char *type,
775
const char *domain,
776
AVAHI_GCC_UNUSED AvahiLookupResultFlags
777
flags,
778
void* userdata) {
779
mandos_context *mc = userdata;
780
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
}
781
1561
782
1562
/* Called whenever a new services becomes available on the LAN or
783
1563
is removed from the LAN */
784
1564
785
switch(event) {
1565
if(quit_now){
1566
return;
1567
}
1568
1569
switch(event){
786
1570
default:
787
1571
case AVAHI_BROWSER_FAILURE:
788
1572
789
fprintf(stderr, "(Avahi browser) %s\n",
790
avahi_strerror(avahi_server_errno(mc->server)));
791
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);
792
1577
return;
793
1578
794
1579
case AVAHI_BROWSER_NEW:
797
1582
the callback function is called the Avahi server will free the
798
1583
resolver for us. */
799
1584
800
if(!(avahi_s_service_resolver_new(mc->server, interface,
801
protocol, name, type, domain,
802
AVAHI_PROTO_INET6, 0,
803
resolve_callback, mc)))
804
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
805
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)));
806
1593
break;
807
1594
808
1595
case AVAHI_BROWSER_REMOVE:
811
1598
case AVAHI_BROWSER_ALL_FOR_NOW:
812
1599
case AVAHI_BROWSER_CACHE_EXHAUSTED:
813
1600
if(debug){
814
fprintf(stderr, "No Mandos server found, still searching...\n");
1601
fprintf_plus(stderr, "No Mandos server found, still"
1602
" searching...\n");
815
1603
}
816
1604
break;
817
1605
}
818
1606
}
819
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
820
2277
int main(int argc, char *argv[]){
821
AvahiSServiceBrowser *sb = NULL;
822
int error;
823
int ret;
824
intmax_t tmpmax;
825
int numchars;
826
int exitcode = EXIT_SUCCESS;
827
const char *interface = "eth0";
828
struct ifreq network;
829
int sd;
830
uid_t uid;
831
gid_t gid;
832
char *connect_to = NULL;
833
char tempdir[] = "/tmp/mandosXXXXXX";
834
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
835
const char *seckey = PATHDIR "/" SECKEY;
836
const char *pubkey = PATHDIR "/" PUBKEY;
837
838
mandos_context mc = { .simple_poll = NULL, .server = NULL,
839
.dh_bits = 1024, .priority = "SECURE256"
840
":!CTYPE-X.509:+CTYPE-OPENPGP" };
841
bool gnutls_initalized = false;
842
bool gpgme_initalized = false;
843
844
{
845
struct argp_option options[] = {
846
{ .name = "debug", .key = 128,
847
.doc = "Debug mode", .group = 3 },
848
{ .name = "connect", .key = 'c',
849
.arg = "ADDRESS:PORT",
850
.doc = "Connect directly to a specific Mandos server",
851
.group = 1 },
852
{ .name = "interface", .key = 'i',
853
.arg = "NAME",
854
.doc = "Interface that will be used to search for Mandos"
855
" servers",
856
.group = 1 },
857
{ .name = "seckey", .key = 's',
858
.arg = "FILE",
859
.doc = "OpenPGP secret key file base name",
860
.group = 1 },
861
{ .name = "pubkey", .key = 'p',
862
.arg = "FILE",
863
.doc = "OpenPGP public key file base name",
864
.group = 2 },
865
{ .name = "dh-bits", .key = 129,
866
.arg = "BITS",
867
.doc = "Bit length of the prime number used in the"
868
" Diffie-Hellman key exchange",
869
.group = 2 },
870
{ .name = "priority", .key = 130,
871
.arg = "STRING",
872
.doc = "GnuTLS priority string for the TLS handshake",
873
.group = 1 },
874
{ .name = NULL }
875
};
876
877
error_t parse_opt(int key, char *arg,
878
struct argp_state *state) {
879
switch(key) {
880
case 128: /* --debug */
881
debug = true;
882
break;
883
case 'c': /* --connect */
884
connect_to = arg;
885
break;
886
case 'i': /* --interface */
887
interface = arg;
888
break;
889
case 's': /* --seckey */
890
seckey = arg;
891
break;
892
case 'p': /* --pubkey */
893
pubkey = arg;
894
break;
895
case 129: /* --dh-bits */
896
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
897
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
898
or arg[numchars] != '\0'){
899
fprintf(stderr, "Bad number of DH bits\n");
900
exit(EXIT_FAILURE);
901
}
902
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
903
break;
904
case 130: /* --priority */
905
mc.priority = arg;
906
break;
907
case ARGP_KEY_ARG:
908
argp_usage(state);
909
case ARGP_KEY_END:
910
break;
911
default:
912
return ARGP_ERR_UNKNOWN;
913
}
914
return 0;
915
}
916
917
struct argp argp = { .options = options, .parser = parse_opt,
918
.args_doc = "",
919
.doc = "Mandos client -- Get and decrypt"
920
" passwords from a Mandos server" };
921
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
922
if(ret == ARGP_ERR_UNKNOWN){
923
fprintf(stderr, "Unknown error while parsing arguments\n");
924
exitcode = EXIT_FAILURE;
925
goto end;
926
}
927
}
928
929
/* If the interface is down, bring it up */
930
{
931
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
932
if(sd < 0) {
933
perror("socket");
934
exitcode = EXIT_FAILURE;
935
goto end;
936
}
937
strcpy(network.ifr_name, interface);
938
ret = ioctl(sd, SIOCGIFFLAGS, &network);
939
if(ret == -1){
940
perror("ioctl SIOCGIFFLAGS");
941
exitcode = EXIT_FAILURE;
942
goto end;
943
}
944
if((network.ifr_flags & IFF_UP) == 0){
945
network.ifr_flags |= IFF_UP;
946
ret = ioctl(sd, SIOCSIFFLAGS, &network);
947
if(ret == -1){
948
perror("ioctl SIOCSIFFLAGS");
949
exitcode = EXIT_FAILURE;
950
goto end;
951
}
952
}
953
ret = (int)TEMP_FAILURE_RETRY(close(sd));
954
if(ret == -1){
955
perror("close");
956
}
957
}
958
959
uid = getuid();
960
gid = getgid();
961
962
ret = setuid(uid);
963
if(ret == -1){
964
perror("setuid");
965
}
966
967
setgid(gid);
968
if(ret == -1){
969
perror("setgid");
970
}
971
972
ret = init_gnutls_global(&mc, pubkey, seckey);
973
if(ret == -1){
974
fprintf(stderr, "init_gnutls_global failed\n");
975
exitcode = EXIT_FAILURE;
976
goto end;
977
} else {
978
gnutls_initalized = true;
979
}
980
981
if(mkdtemp(tempdir) == NULL){
982
perror("mkdtemp");
983
tempdir[0] = '\0';
984
goto end;
985
}
986
987
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
988
fprintf(stderr, "gpgme_initalized failed\n");
989
exitcode = EXIT_FAILURE;
990
goto end;
991
} else {
992
gpgme_initalized = true;
993
}
994
995
if_index = (AvahiIfIndex) if_nametoindex(interface);
996
if(if_index == 0){
997
fprintf(stderr, "No such interface: \"%s\"\n", interface);
998
exit(EXIT_FAILURE);
999
}
1000
1001
if(connect_to != NULL){
1002
/* Connect directly, do not use Zeroconf */
1003
/* (Mainly meant for debugging) */
1004
char *address = strrchr(connect_to, ':');
1005
if(address == NULL){
1006
fprintf(stderr, "No colon in address\n");
1007
exitcode = EXIT_FAILURE;
1008
goto end;
1009
}
1010
uint16_t port;
1011
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1012
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1013
or address[numchars+1] != '\0'){
1014
fprintf(stderr, "Bad port number\n");
1015
exitcode = EXIT_FAILURE;
1016
goto end;
1017
}
1018
port = (uint16_t)tmpmax;
1019
*address = '\0';
1020
address = connect_to;
1021
ret = start_mandos_communication(address, port, if_index, &mc);
1022
if(ret < 0){
1023
exitcode = EXIT_FAILURE;
1024
} else {
1025
exitcode = EXIT_SUCCESS;
1026
}
1027
goto end;
1028
}
1029
1030
if(not debug){
1031
avahi_set_log_function(empty_log);
1032
}
1033
1034
/* Initialize the pseudo-RNG for Avahi */
1035
srand((unsigned int) time(NULL));
1036
1037
/* Allocate main Avahi loop object */
1038
mc.simple_poll = avahi_simple_poll_new();
1039
if(mc.simple_poll == NULL) {
1040
fprintf(stderr, "Avahi: Failed to create simple poll"
1041
" object.\n");
1042
exitcode = EXIT_FAILURE;
1043
goto end;
1044
}
1045
1046
{
1047
AvahiServerConfig config;
1048
/* Do not publish any local Zeroconf records */
1049
avahi_server_config_init(&config);
1050
config.publish_hinfo = 0;
1051
config.publish_addresses = 0;
1052
config.publish_workstation = 0;
1053
config.publish_domain = 0;
1054
1055
/* Allocate a new server */
1056
mc.server = avahi_server_new(avahi_simple_poll_get
1057
(mc.simple_poll), &config, NULL,
1058
NULL, &error);
1059
1060
/* Free the Avahi configuration data */
1061
avahi_server_config_free(&config);
1062
}
1063
1064
/* Check if creating the Avahi server object succeeded */
1065
if(mc.server == NULL) {
1066
fprintf(stderr, "Failed to create Avahi server: %s\n",
1067
avahi_strerror(error));
1068
exitcode = EXIT_FAILURE;
1069
goto end;
1070
}
1071
1072
/* Create the Avahi service browser */
1073
sb = avahi_s_service_browser_new(mc.server, if_index,
1074
AVAHI_PROTO_INET6,
1075
"_mandos._tcp", NULL, 0,
1076
browse_callback, &mc);
1077
if(sb == NULL) {
1078
fprintf(stderr, "Failed to create service browser: %s\n",
1079
avahi_strerror(avahi_server_errno(mc.server)));
1080
exitcode = EXIT_FAILURE;
1081
goto end;
1082
}
1083
1084
/* Run the main loop */
1085
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){
1086
2760
if(debug){
1087
fprintf(stderr, "Starting Avahi loop search\n");
1088
}
1089
1090
avahi_simple_poll_loop(mc.simple_poll);
1091
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
1092
2946
end:
1093
1094
if(debug){
1095
fprintf(stderr, "%s exiting\n", argv[0]);
1096
}
1097
1098
/* Cleanup things */
1099
if(sb != NULL)
1100
avahi_s_service_browser_free(sb);
1101
1102
if(mc.server != NULL)
1103
avahi_server_free(mc.server);
1104
1105
if(mc.simple_poll != NULL)
1106
avahi_simple_poll_free(mc.simple_poll);
1107
1108
if(gnutls_initalized){
1109
gnutls_certificate_free_credentials(mc.cred);
1110
gnutls_global_deinit();
1111
gnutls_dh_params_deinit(mc.dh_params);
1112
}
1113
1114
if(gpgme_initalized){
1115
gpgme_release(mc.ctx);
1116
}
1117
1118
/* Removes the temp directory used by GPGME */
1119
if(tempdir[0] != '\0'){
1120
DIR *d;
1121
struct dirent *direntry;
1122
d = opendir(tempdir);
1123
if(d == NULL){
1124
if(errno != ENOENT){
1125
perror("opendir");
1126
}
1127
} else {
1128
while(true){
1129
direntry = readdir(d);
1130
if(direntry == NULL){
1131
break;
1132
}
1133
if(direntry->d_type == DT_REG){
1134
char *fullname = NULL;
1135
ret = asprintf(&fullname, "%s/%s", tempdir,
1136
direntry->d_name);
1137
if(ret < 0){
1138
perror("asprintf");
1139
continue;
1140
}
1141
ret = unlink(fullname);
1142
if(ret == -1){
1143
fprintf(stderr, "unlink(\"%s\"): %s",
1144
fullname, strerror(errno));
1145
}
1146
free(fullname);
1147
}
1148
}
1149
closedir(d);
1150
}
1151
ret = rmdir(tempdir);
1152
if(ret == -1 and errno != ENOENT){
1153
perror("rmdir");
1154
}
1155
}
1156
1157
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;
1158
3114
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0