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- Committer: Teddy Hogeborn
- Date: 2008-10-07 21:31:09 UTC
- Revision ID: teddy@fukt.bsnet.se-20081007213109-jylxoydo3iyb3y8i
Tags: version-1.0.1-1
* Makefile (version): Changed to "1.0.1".
* mandos (version): - '' -
* mandos-keygen (version): - '' -
* NEWS: New file.
* debian/changelog: New entry for "1.0.1-1".
* mandos-clients.conf.xml (OPTIONS): Document ~username and $ENVVAR
expansion for "secfile" option.
* mandos (version): - '' -
* mandos-keygen (version): - '' -
* NEWS: New file.
* debian/changelog: New entry for "1.0.1-1".
* mandos-clients.conf.xml (OPTIONS): Document ~username and $ENVVAR
expansion for "secfile" option.
added
removed
plugins.d/mandos-client.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos client - get and decrypt data from a Mandos server
4
*
5
* This program is partly derived from an example program for an Avahi
6
* service browser, downloaded from
7
* <http://avahi.org/browser/examples/core-browse-services.c>. This
8
* includes the following functions: "resolve_callback",
9
* "browse_callback", and parts of "main".
10
*
11
* Everything else is
12
* Copyright © 2008 Teddy Hogeborn & Björn Påhlsson
13
*
14
* This program is free software: you can redistribute it and/or
15
* modify it under the terms of the GNU General Public License as
16
* published by the Free Software Foundation, either version 3 of the
17
* License, or (at your option) any later version.
18
*
19
* This program is distributed in the hope that it will be useful, but
20
* WITHOUT ANY WARRANTY; without even the implied warranty of
21
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22
* General Public License for more details.
23
*
24
* You should have received a copy of the GNU General Public License
25
* along with this program. If not, see
26
* <http://www.gnu.org/licenses/>.
27
*
28
* Contact the authors at <mandos@fukt.bsnet.se>.
29
*/
30
31
/* Needed by GPGME, specifically gpgme_data_seek() */
32
#define _LARGEFILE_SOURCE
33
#define _FILE_OFFSET_BITS 64
34
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
36
37
#include <stdio.h> /* fprintf(), stderr, fwrite(),
38
stdout, ferror() */
39
#include <stdint.h> /* uint16_t, uint32_t */
40
#include <stddef.h> /* NULL, size_t, ssize_t */
41
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
42
srand() */
43
#include <stdbool.h> /* bool, true */
44
#include <string.h> /* memset(), strcmp(), strlen(),
45
strerror(), asprintf(), strcpy() */
46
#include <sys/ioctl.h> /* ioctl */
47
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
48
sockaddr_in6, PF_INET6,
49
SOCK_STREAM, INET6_ADDRSTRLEN,
50
uid_t, gid_t, open(), opendir(), DIR */
51
#include <sys/stat.h> /* open() */
52
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
53
struct in6_addr, inet_pton(),
54
connect() */
55
#include <fcntl.h> /* open() */
56
#include <dirent.h> /* opendir(), struct dirent, readdir() */
57
#include <inttypes.h> /* PRIu16 */
58
#include <assert.h> /* assert() */
59
#include <errno.h> /* perror(), errno */
60
#include <time.h> /* time() */
61
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
62
SIOCSIFFLAGS, if_indextoname(),
63
if_nametoindex(), IF_NAMESIZE */
64
#include <netinet/in.h>
65
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
66
getuid(), getgid(), setuid(),
67
setgid() */
68
#include <arpa/inet.h> /* inet_pton(), htons */
69
#include <iso646.h> /* not, and */
70
#include <argp.h> /* struct argp_option, error_t, struct
71
argp_state, struct argp,
72
argp_parse(), ARGP_KEY_ARG,
73
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
74
75
/* Avahi */
76
/* All Avahi types, constants and functions
77
Avahi*, avahi_*,
78
AVAHI_* */
79
#include <avahi-core/core.h>
80
#include <avahi-core/lookup.h>
81
#include <avahi-core/log.h>
82
#include <avahi-common/simple-watch.h>
83
#include <avahi-common/malloc.h>
84
#include <avahi-common/error.h>
85
86
/* GnuTLS */
87
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
88
functions:
89
gnutls_*
90
init_gnutls_session(),
91
GNUTLS_* */
92
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
93
GNUTLS_OPENPGP_FMT_BASE64 */
94
95
/* GPGME */
96
#include <gpgme.h> /* All GPGME types, constants and
97
functions:
98
gpgme_*
99
GPGME_PROTOCOL_OpenPGP,
100
GPG_ERR_NO_* */
101
102
#define BUFFER_SIZE 256
103
104
#define PATHDIR "/conf/conf.d/mandos"
105
#define SECKEY "seckey.txt"
106
#define PUBKEY "pubkey.txt"
107
108
bool debug = false;
109
static const char mandos_protocol_version[] = "1";
110
const char *argp_program_version = "mandos-client " VERSION;
111
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
112
113
/* Used for passing in values through the Avahi callback functions */
114
typedef struct {
115
AvahiSimplePoll *simple_poll;
116
AvahiServer *server;
117
gnutls_certificate_credentials_t cred;
118
unsigned int dh_bits;
119
gnutls_dh_params_t dh_params;
120
const char *priority;
121
gpgme_ctx_t ctx;
122
} mandos_context;
123
124
/*
125
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
126
* "buffer_capacity" is how much is currently allocated,
127
* "buffer_length" is how much is already used.
128
*/
129
size_t adjustbuffer(char **buffer, size_t buffer_length,
130
size_t buffer_capacity){
131
if (buffer_length + BUFFER_SIZE > buffer_capacity){
132
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
133
if (buffer == NULL){
134
return 0;
135
}
136
buffer_capacity += BUFFER_SIZE;
137
}
138
return buffer_capacity;
139
}
140
141
/*
142
* Initialize GPGME.
143
*/
144
static bool init_gpgme(mandos_context *mc, const char *seckey,
145
const char *pubkey, const char *tempdir){
146
int ret;
147
gpgme_error_t rc;
148
gpgme_engine_info_t engine_info;
149
150
151
/*
152
* Helper function to insert pub and seckey to the enigne keyring.
153
*/
154
bool import_key(const char *filename){
155
int fd;
156
gpgme_data_t pgp_data;
157
158
fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
159
if(fd == -1){
160
perror("open");
161
return false;
162
}
163
164
rc = gpgme_data_new_from_fd(&pgp_data, fd);
165
if (rc != GPG_ERR_NO_ERROR){
166
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
167
gpgme_strsource(rc), gpgme_strerror(rc));
168
return false;
169
}
170
171
rc = gpgme_op_import(mc->ctx, pgp_data);
172
if (rc != GPG_ERR_NO_ERROR){
173
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
174
gpgme_strsource(rc), gpgme_strerror(rc));
175
return false;
176
}
177
178
ret = TEMP_FAILURE_RETRY(close(fd));
179
if(ret == -1){
180
perror("close");
181
}
182
gpgme_data_release(pgp_data);
183
return true;
184
}
185
186
if (debug){
187
fprintf(stderr, "Initialize gpgme\n");
188
}
189
190
/* Init GPGME */
191
gpgme_check_version(NULL);
192
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
193
if (rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
196
return false;
197
}
198
199
/* Set GPGME home directory for the OpenPGP engine only */
200
rc = gpgme_get_engine_info (&engine_info);
201
if (rc != GPG_ERR_NO_ERROR){
202
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
203
gpgme_strsource(rc), gpgme_strerror(rc));
204
return false;
205
}
206
while(engine_info != NULL){
207
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
208
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
209
engine_info->file_name, tempdir);
210
break;
211
}
212
engine_info = engine_info->next;
213
}
214
if(engine_info == NULL){
215
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
216
return false;
217
}
218
219
/* Create new GPGME "context" */
220
rc = gpgme_new(&(mc->ctx));
221
if (rc != GPG_ERR_NO_ERROR){
222
fprintf(stderr, "bad gpgme_new: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
224
return false;
225
}
226
227
if (not import_key(pubkey) or not import_key(seckey)){
228
return false;
229
}
230
231
return true;
232
}
233
234
/*
235
* Decrypt OpenPGP data.
236
* Returns -1 on error
237
*/
238
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
239
const char *cryptotext,
240
size_t crypto_size,
241
char **plaintext){
242
gpgme_data_t dh_crypto, dh_plain;
243
gpgme_error_t rc;
244
ssize_t ret;
245
size_t plaintext_capacity = 0;
246
ssize_t plaintext_length = 0;
247
248
if (debug){
249
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
250
}
251
252
/* Create new GPGME data buffer from memory cryptotext */
253
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
254
0);
255
if (rc != GPG_ERR_NO_ERROR){
256
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
257
gpgme_strsource(rc), gpgme_strerror(rc));
258
return -1;
259
}
260
261
/* Create new empty GPGME data buffer for the plaintext */
262
rc = gpgme_data_new(&dh_plain);
263
if (rc != GPG_ERR_NO_ERROR){
264
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
265
gpgme_strsource(rc), gpgme_strerror(rc));
266
gpgme_data_release(dh_crypto);
267
return -1;
268
}
269
270
/* Decrypt data from the cryptotext data buffer to the plaintext
271
data buffer */
272
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
273
if (rc != GPG_ERR_NO_ERROR){
274
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
275
gpgme_strsource(rc), gpgme_strerror(rc));
276
plaintext_length = -1;
277
if (debug){
278
gpgme_decrypt_result_t result;
279
result = gpgme_op_decrypt_result(mc->ctx);
280
if (result == NULL){
281
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
282
} else {
283
fprintf(stderr, "Unsupported algorithm: %s\n",
284
result->unsupported_algorithm);
285
fprintf(stderr, "Wrong key usage: %u\n",
286
result->wrong_key_usage);
287
if(result->file_name != NULL){
288
fprintf(stderr, "File name: %s\n", result->file_name);
289
}
290
gpgme_recipient_t recipient;
291
recipient = result->recipients;
292
if(recipient){
293
while(recipient != NULL){
294
fprintf(stderr, "Public key algorithm: %s\n",
295
gpgme_pubkey_algo_name(recipient->pubkey_algo));
296
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
297
fprintf(stderr, "Secret key available: %s\n",
298
recipient->status == GPG_ERR_NO_SECKEY
299
? "No" : "Yes");
300
recipient = recipient->next;
301
}
302
}
303
}
304
}
305
goto decrypt_end;
306
}
307
308
if(debug){
309
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
310
}
311
312
/* Seek back to the beginning of the GPGME plaintext data buffer */
313
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
314
perror("gpgme_data_seek");
315
plaintext_length = -1;
316
goto decrypt_end;
317
}
318
319
*plaintext = NULL;
320
while(true){
321
plaintext_capacity = adjustbuffer(plaintext,
322
(size_t)plaintext_length,
323
plaintext_capacity);
324
if (plaintext_capacity == 0){
325
perror("adjustbuffer");
326
plaintext_length = -1;
327
goto decrypt_end;
328
}
329
330
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
331
BUFFER_SIZE);
332
/* Print the data, if any */
333
if (ret == 0){
334
/* EOF */
335
break;
336
}
337
if(ret < 0){
338
perror("gpgme_data_read");
339
plaintext_length = -1;
340
goto decrypt_end;
341
}
342
plaintext_length += ret;
343
}
344
345
if(debug){
346
fprintf(stderr, "Decrypted password is: ");
347
for(ssize_t i = 0; i < plaintext_length; i++){
348
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
349
}
350
fprintf(stderr, "\n");
351
}
352
353
decrypt_end:
354
355
/* Delete the GPGME cryptotext data buffer */
356
gpgme_data_release(dh_crypto);
357
358
/* Delete the GPGME plaintext data buffer */
359
gpgme_data_release(dh_plain);
360
return plaintext_length;
361
}
362
363
static const char * safer_gnutls_strerror (int value) {
364
const char *ret = gnutls_strerror (value); /* Spurious warning */
365
if (ret == NULL)
366
ret = "(unknown)";
367
return ret;
368
}
369
370
/* GnuTLS log function callback */
371
static void debuggnutls(__attribute__((unused)) int level,
372
const char* string){
373
fprintf(stderr, "GnuTLS: %s", string);
374
}
375
376
static int init_gnutls_global(mandos_context *mc,
377
const char *pubkeyfilename,
378
const char *seckeyfilename){
379
int ret;
380
381
if(debug){
382
fprintf(stderr, "Initializing GnuTLS\n");
383
}
384
385
ret = gnutls_global_init();
386
if (ret != GNUTLS_E_SUCCESS) {
387
fprintf (stderr, "GnuTLS global_init: %s\n",
388
safer_gnutls_strerror(ret));
389
return -1;
390
}
391
392
if (debug){
393
/* "Use a log level over 10 to enable all debugging options."
394
* - GnuTLS manual
395
*/
396
gnutls_global_set_log_level(11);
397
gnutls_global_set_log_function(debuggnutls);
398
}
399
400
/* OpenPGP credentials */
401
gnutls_certificate_allocate_credentials(&mc->cred);
402
if (ret != GNUTLS_E_SUCCESS){
403
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
404
warning */
405
safer_gnutls_strerror(ret));
406
gnutls_global_deinit ();
407
return -1;
408
}
409
410
if(debug){
411
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
412
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
413
seckeyfilename);
414
}
415
416
ret = gnutls_certificate_set_openpgp_key_file
417
(mc->cred, pubkeyfilename, seckeyfilename,
418
GNUTLS_OPENPGP_FMT_BASE64);
419
if (ret != GNUTLS_E_SUCCESS) {
420
fprintf(stderr,
421
"Error[%d] while reading the OpenPGP key pair ('%s',"
422
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
423
fprintf(stderr, "The GnuTLS error is: %s\n",
424
safer_gnutls_strerror(ret));
425
goto globalfail;
426
}
427
428
/* GnuTLS server initialization */
429
ret = gnutls_dh_params_init(&mc->dh_params);
430
if (ret != GNUTLS_E_SUCCESS) {
431
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
432
" %s\n", safer_gnutls_strerror(ret));
433
goto globalfail;
434
}
435
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
436
if (ret != GNUTLS_E_SUCCESS) {
437
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
438
safer_gnutls_strerror(ret));
439
goto globalfail;
440
}
441
442
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
443
444
return 0;
445
446
globalfail:
447
448
gnutls_certificate_free_credentials(mc->cred);
449
gnutls_global_deinit();
450
gnutls_dh_params_deinit(mc->dh_params);
451
return -1;
452
}
453
454
static int init_gnutls_session(mandos_context *mc,
455
gnutls_session_t *session){
456
int ret;
457
/* GnuTLS session creation */
458
ret = gnutls_init(session, GNUTLS_SERVER);
459
if (ret != GNUTLS_E_SUCCESS){
460
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
461
safer_gnutls_strerror(ret));
462
}
463
464
{
465
const char *err;
466
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
467
if (ret != GNUTLS_E_SUCCESS) {
468
fprintf(stderr, "Syntax error at: %s\n", err);
469
fprintf(stderr, "GnuTLS error: %s\n",
470
safer_gnutls_strerror(ret));
471
gnutls_deinit (*session);
472
return -1;
473
}
474
}
475
476
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
477
mc->cred);
478
if (ret != GNUTLS_E_SUCCESS) {
479
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
480
safer_gnutls_strerror(ret));
481
gnutls_deinit (*session);
482
return -1;
483
}
484
485
/* ignore client certificate if any. */
486
gnutls_certificate_server_set_request (*session,
487
GNUTLS_CERT_IGNORE);
488
489
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
490
491
return 0;
492
}
493
494
/* Avahi log function callback */
495
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
496
__attribute__((unused)) const char *txt){}
497
498
/* Called when a Mandos server is found */
499
static int start_mandos_communication(const char *ip, uint16_t port,
500
AvahiIfIndex if_index,
501
mandos_context *mc){
502
int ret, tcp_sd;
503
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
504
char *buffer = NULL;
505
char *decrypted_buffer;
506
size_t buffer_length = 0;
507
size_t buffer_capacity = 0;
508
ssize_t decrypted_buffer_size;
509
size_t written;
510
int retval = 0;
511
char interface[IF_NAMESIZE];
512
gnutls_session_t session;
513
514
ret = init_gnutls_session (mc, &session);
515
if (ret != 0){
516
return -1;
517
}
518
519
if(debug){
520
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
521
"\n", ip, port);
522
}
523
524
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
525
if(tcp_sd < 0) {
526
perror("socket");
527
return -1;
528
}
529
530
if(debug){
531
if(if_indextoname((unsigned int)if_index, interface) == NULL){
532
perror("if_indextoname");
533
return -1;
534
}
535
fprintf(stderr, "Binding to interface %s\n", interface);
536
}
537
538
memset(&to, 0, sizeof(to));
539
to.in6.sin6_family = AF_INET6;
540
/* It would be nice to have a way to detect if we were passed an
541
IPv4 address here. Now we assume an IPv6 address. */
542
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
543
if (ret < 0 ){
544
perror("inet_pton");
545
return -1;
546
}
547
if(ret == 0){
548
fprintf(stderr, "Bad address: %s\n", ip);
549
return -1;
550
}
551
to.in6.sin6_port = htons(port); /* Spurious warning */
552
553
to.in6.sin6_scope_id = (uint32_t)if_index;
554
555
if(debug){
556
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
557
port);
558
char addrstr[INET6_ADDRSTRLEN] = "";
559
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
560
sizeof(addrstr)) == NULL){
561
perror("inet_ntop");
562
} else {
563
if(strcmp(addrstr, ip) != 0){
564
fprintf(stderr, "Canonical address form: %s\n", addrstr);
565
}
566
}
567
}
568
569
ret = connect(tcp_sd, &to.in, sizeof(to));
570
if (ret < 0){
571
perror("connect");
572
return -1;
573
}
574
575
const char *out = mandos_protocol_version;
576
written = 0;
577
while (true){
578
size_t out_size = strlen(out);
579
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
580
out_size - written));
581
if (ret == -1){
582
perror("write");
583
retval = -1;
584
goto mandos_end;
585
}
586
written += (size_t)ret;
587
if(written < out_size){
588
continue;
589
} else {
590
if (out == mandos_protocol_version){
591
written = 0;
592
out = "\r\n";
593
} else {
594
break;
595
}
596
}
597
}
598
599
if(debug){
600
fprintf(stderr, "Establishing TLS session with %s\n", ip);
601
}
602
603
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
604
605
do{
606
ret = gnutls_handshake (session);
607
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
608
609
if (ret != GNUTLS_E_SUCCESS){
610
if(debug){
611
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
612
gnutls_perror (ret);
613
}
614
retval = -1;
615
goto mandos_end;
616
}
617
618
/* Read OpenPGP packet that contains the wanted password */
619
620
if(debug){
621
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
622
ip);
623
}
624
625
while(true){
626
buffer_capacity = adjustbuffer(&buffer, buffer_length,
627
buffer_capacity);
628
if (buffer_capacity == 0){
629
perror("adjustbuffer");
630
retval = -1;
631
goto mandos_end;
632
}
633
634
ret = gnutls_record_recv(session, buffer+buffer_length,
635
BUFFER_SIZE);
636
if (ret == 0){
637
break;
638
}
639
if (ret < 0){
640
switch(ret){
641
case GNUTLS_E_INTERRUPTED:
642
case GNUTLS_E_AGAIN:
643
break;
644
case GNUTLS_E_REHANDSHAKE:
645
do{
646
ret = gnutls_handshake (session);
647
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
648
if (ret < 0){
649
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
650
gnutls_perror (ret);
651
retval = -1;
652
goto mandos_end;
653
}
654
break;
655
default:
656
fprintf(stderr, "Unknown error while reading data from"
657
" encrypted session with Mandos server\n");
658
retval = -1;
659
gnutls_bye (session, GNUTLS_SHUT_RDWR);
660
goto mandos_end;
661
}
662
} else {
663
buffer_length += (size_t) ret;
664
}
665
}
666
667
if(debug){
668
fprintf(stderr, "Closing TLS session\n");
669
}
670
671
gnutls_bye (session, GNUTLS_SHUT_RDWR);
672
673
if (buffer_length > 0){
674
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
675
buffer_length,
676
&decrypted_buffer);
677
if (decrypted_buffer_size >= 0){
678
written = 0;
679
while(written < (size_t) decrypted_buffer_size){
680
ret = (int)fwrite (decrypted_buffer + written, 1,
681
(size_t)decrypted_buffer_size - written,
682
stdout);
683
if(ret == 0 and ferror(stdout)){
684
if(debug){
685
fprintf(stderr, "Error writing encrypted data: %s\n",
686
strerror(errno));
687
}
688
retval = -1;
689
break;
690
}
691
written += (size_t)ret;
692
}
693
free(decrypted_buffer);
694
} else {
695
retval = -1;
696
}
697
} else {
698
retval = -1;
699
}
700
701
/* Shutdown procedure */
702
703
mandos_end:
704
free(buffer);
705
ret = TEMP_FAILURE_RETRY(close(tcp_sd));
706
if(ret == -1){
707
perror("close");
708
}
709
gnutls_deinit (session);
710
return retval;
711
}
712
713
static void resolve_callback(AvahiSServiceResolver *r,
714
AvahiIfIndex interface,
715
AVAHI_GCC_UNUSED AvahiProtocol protocol,
716
AvahiResolverEvent event,
717
const char *name,
718
const char *type,
719
const char *domain,
720
const char *host_name,
721
const AvahiAddress *address,
722
uint16_t port,
723
AVAHI_GCC_UNUSED AvahiStringList *txt,
724
AVAHI_GCC_UNUSED AvahiLookupResultFlags
725
flags,
726
void* userdata) {
727
mandos_context *mc = userdata;
728
assert(r);
729
730
/* Called whenever a service has been resolved successfully or
731
timed out */
732
733
switch (event) {
734
default:
735
case AVAHI_RESOLVER_FAILURE:
736
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
737
" of type '%s' in domain '%s': %s\n", name, type, domain,
738
avahi_strerror(avahi_server_errno(mc->server)));
739
break;
740
741
case AVAHI_RESOLVER_FOUND:
742
{
743
char ip[AVAHI_ADDRESS_STR_MAX];
744
avahi_address_snprint(ip, sizeof(ip), address);
745
if(debug){
746
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
747
PRIu16 ") on port %d\n", name, host_name, ip,
748
interface, port);
749
}
750
int ret = start_mandos_communication(ip, port, interface, mc);
751
if (ret == 0){
752
avahi_simple_poll_quit(mc->simple_poll);
753
}
754
}
755
}
756
avahi_s_service_resolver_free(r);
757
}
758
759
static void browse_callback( AvahiSServiceBrowser *b,
760
AvahiIfIndex interface,
761
AvahiProtocol protocol,
762
AvahiBrowserEvent event,
763
const char *name,
764
const char *type,
765
const char *domain,
766
AVAHI_GCC_UNUSED AvahiLookupResultFlags
767
flags,
768
void* userdata) {
769
mandos_context *mc = userdata;
770
assert(b);
771
772
/* Called whenever a new services becomes available on the LAN or
773
is removed from the LAN */
774
775
switch (event) {
776
default:
777
case AVAHI_BROWSER_FAILURE:
778
779
fprintf(stderr, "(Avahi browser) %s\n",
780
avahi_strerror(avahi_server_errno(mc->server)));
781
avahi_simple_poll_quit(mc->simple_poll);
782
return;
783
784
case AVAHI_BROWSER_NEW:
785
/* We ignore the returned Avahi resolver object. In the callback
786
function we free it. If the Avahi server is terminated before
787
the callback function is called the Avahi server will free the
788
resolver for us. */
789
790
if (!(avahi_s_service_resolver_new(mc->server, interface,
791
protocol, name, type, domain,
792
AVAHI_PROTO_INET6, 0,
793
resolve_callback, mc)))
794
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
795
name, avahi_strerror(avahi_server_errno(mc->server)));
796
break;
797
798
case AVAHI_BROWSER_REMOVE:
799
break;
800
801
case AVAHI_BROWSER_ALL_FOR_NOW:
802
case AVAHI_BROWSER_CACHE_EXHAUSTED:
803
if(debug){
804
fprintf(stderr, "No Mandos server found, still searching...\n");
805
}
806
break;
807
}
808
}
809
810
int main(int argc, char *argv[]){
811
AvahiSServiceBrowser *sb = NULL;
812
int error;
813
int ret;
814
int exitcode = EXIT_SUCCESS;
815
const char *interface = "eth0";
816
struct ifreq network;
817
int sd;
818
uid_t uid;
819
gid_t gid;
820
char *connect_to = NULL;
821
char tempdir[] = "/tmp/mandosXXXXXX";
822
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
823
const char *seckey = PATHDIR "/" SECKEY;
824
const char *pubkey = PATHDIR "/" PUBKEY;
825
826
mandos_context mc = { .simple_poll = NULL, .server = NULL,
827
.dh_bits = 1024, .priority = "SECURE256"
828
":!CTYPE-X.509:+CTYPE-OPENPGP" };
829
bool gnutls_initalized = false;
830
bool gpgme_initalized = false;
831
832
{
833
struct argp_option options[] = {
834
{ .name = "debug", .key = 128,
835
.doc = "Debug mode", .group = 3 },
836
{ .name = "connect", .key = 'c',
837
.arg = "ADDRESS:PORT",
838
.doc = "Connect directly to a specific Mandos server",
839
.group = 1 },
840
{ .name = "interface", .key = 'i',
841
.arg = "NAME",
842
.doc = "Interface that will be used to search for Mandos"
843
" servers",
844
.group = 1 },
845
{ .name = "seckey", .key = 's',
846
.arg = "FILE",
847
.doc = "OpenPGP secret key file base name",
848
.group = 1 },
849
{ .name = "pubkey", .key = 'p',
850
.arg = "FILE",
851
.doc = "OpenPGP public key file base name",
852
.group = 2 },
853
{ .name = "dh-bits", .key = 129,
854
.arg = "BITS",
855
.doc = "Bit length of the prime number used in the"
856
" Diffie-Hellman key exchange",
857
.group = 2 },
858
{ .name = "priority", .key = 130,
859
.arg = "STRING",
860
.doc = "GnuTLS priority string for the TLS handshake",
861
.group = 1 },
862
{ .name = NULL }
863
};
864
865
error_t parse_opt (int key, char *arg,
866
struct argp_state *state) {
867
/* Get the INPUT argument from `argp_parse', which we know is
868
a pointer to our plugin list pointer. */
869
switch (key) {
870
case 128: /* --debug */
871
debug = true;
872
break;
873
case 'c': /* --connect */
874
connect_to = arg;
875
break;
876
case 'i': /* --interface */
877
interface = arg;
878
break;
879
case 's': /* --seckey */
880
seckey = arg;
881
break;
882
case 'p': /* --pubkey */
883
pubkey = arg;
884
break;
885
case 129: /* --dh-bits */
886
errno = 0;
887
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
888
if (errno){
889
perror("strtol");
890
exit(EXIT_FAILURE);
891
}
892
break;
893
case 130: /* --priority */
894
mc.priority = arg;
895
break;
896
case ARGP_KEY_ARG:
897
argp_usage (state);
898
case ARGP_KEY_END:
899
break;
900
default:
901
return ARGP_ERR_UNKNOWN;
902
}
903
return 0;
904
}
905
906
struct argp argp = { .options = options, .parser = parse_opt,
907
.args_doc = "",
908
.doc = "Mandos client -- Get and decrypt"
909
" passwords from a Mandos server" };
910
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
911
if (ret == ARGP_ERR_UNKNOWN){
912
fprintf(stderr, "Unknown error while parsing arguments\n");
913
exitcode = EXIT_FAILURE;
914
goto end;
915
}
916
}
917
918
/* If the interface is down, bring it up */
919
{
920
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
921
if(sd < 0) {
922
perror("socket");
923
exitcode = EXIT_FAILURE;
924
goto end;
925
}
926
strcpy(network.ifr_name, interface);
927
ret = ioctl(sd, SIOCGIFFLAGS, &network);
928
if(ret == -1){
929
perror("ioctl SIOCGIFFLAGS");
930
exitcode = EXIT_FAILURE;
931
goto end;
932
}
933
if((network.ifr_flags & IFF_UP) == 0){
934
network.ifr_flags |= IFF_UP;
935
ret = ioctl(sd, SIOCSIFFLAGS, &network);
936
if(ret == -1){
937
perror("ioctl SIOCSIFFLAGS");
938
exitcode = EXIT_FAILURE;
939
goto end;
940
}
941
}
942
ret = TEMP_FAILURE_RETRY(close(sd));
943
if(ret == -1){
944
perror("close");
945
}
946
}
947
948
uid = getuid();
949
gid = getgid();
950
951
ret = setuid(uid);
952
if (ret == -1){
953
perror("setuid");
954
}
955
956
setgid(gid);
957
if (ret == -1){
958
perror("setgid");
959
}
960
961
ret = init_gnutls_global(&mc, pubkey, seckey);
962
if (ret == -1){
963
fprintf(stderr, "init_gnutls_global failed\n");
964
exitcode = EXIT_FAILURE;
965
goto end;
966
} else {
967
gnutls_initalized = true;
968
}
969
970
if(mkdtemp(tempdir) == NULL){
971
perror("mkdtemp");
972
tempdir[0] = '\0';
973
goto end;
974
}
975
976
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
977
fprintf(stderr, "gpgme_initalized failed\n");
978
exitcode = EXIT_FAILURE;
979
goto end;
980
} else {
981
gpgme_initalized = true;
982
}
983
984
if_index = (AvahiIfIndex) if_nametoindex(interface);
985
if(if_index == 0){
986
fprintf(stderr, "No such interface: \"%s\"\n", interface);
987
exit(EXIT_FAILURE);
988
}
989
990
if(connect_to != NULL){
991
/* Connect directly, do not use Zeroconf */
992
/* (Mainly meant for debugging) */
993
char *address = strrchr(connect_to, ':');
994
if(address == NULL){
995
fprintf(stderr, "No colon in address\n");
996
exitcode = EXIT_FAILURE;
997
goto end;
998
}
999
errno = 0;
1000
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1001
if(errno){
1002
perror("Bad port number");
1003
exitcode = EXIT_FAILURE;
1004
goto end;
1005
}
1006
*address = '\0';
1007
address = connect_to;
1008
ret = start_mandos_communication(address, port, if_index, &mc);
1009
if(ret < 0){
1010
exitcode = EXIT_FAILURE;
1011
} else {
1012
exitcode = EXIT_SUCCESS;
1013
}
1014
goto end;
1015
}
1016
1017
if (not debug){
1018
avahi_set_log_function(empty_log);
1019
}
1020
1021
/* Initialize the pseudo-RNG for Avahi */
1022
srand((unsigned int) time(NULL));
1023
1024
/* Allocate main Avahi loop object */
1025
mc.simple_poll = avahi_simple_poll_new();
1026
if (mc.simple_poll == NULL) {
1027
fprintf(stderr, "Avahi: Failed to create simple poll"
1028
" object.\n");
1029
exitcode = EXIT_FAILURE;
1030
goto end;
1031
}
1032
1033
{
1034
AvahiServerConfig config;
1035
/* Do not publish any local Zeroconf records */
1036
avahi_server_config_init(&config);
1037
config.publish_hinfo = 0;
1038
config.publish_addresses = 0;
1039
config.publish_workstation = 0;
1040
config.publish_domain = 0;
1041
1042
/* Allocate a new server */
1043
mc.server = avahi_server_new(avahi_simple_poll_get
1044
(mc.simple_poll), &config, NULL,
1045
NULL, &error);
1046
1047
/* Free the Avahi configuration data */
1048
avahi_server_config_free(&config);
1049
}
1050
1051
/* Check if creating the Avahi server object succeeded */
1052
if (mc.server == NULL) {
1053
fprintf(stderr, "Failed to create Avahi server: %s\n",
1054
avahi_strerror(error));
1055
exitcode = EXIT_FAILURE;
1056
goto end;
1057
}
1058
1059
/* Create the Avahi service browser */
1060
sb = avahi_s_service_browser_new(mc.server, if_index,
1061
AVAHI_PROTO_INET6,
1062
"_mandos._tcp", NULL, 0,
1063
browse_callback, &mc);
1064
if (sb == NULL) {
1065
fprintf(stderr, "Failed to create service browser: %s\n",
1066
avahi_strerror(avahi_server_errno(mc.server)));
1067
exitcode = EXIT_FAILURE;
1068
goto end;
1069
}
1070
1071
/* Run the main loop */
1072
1073
if (debug){
1074
fprintf(stderr, "Starting Avahi loop search\n");
1075
}
1076
1077
avahi_simple_poll_loop(mc.simple_poll);
1078
1079
end:
1080
1081
if (debug){
1082
fprintf(stderr, "%s exiting\n", argv[0]);
1083
}
1084
1085
/* Cleanup things */
1086
if (sb != NULL)
1087
avahi_s_service_browser_free(sb);
1088
1089
if (mc.server != NULL)
1090
avahi_server_free(mc.server);
1091
1092
if (mc.simple_poll != NULL)
1093
avahi_simple_poll_free(mc.simple_poll);
1094
1095
if (gnutls_initalized){
1096
gnutls_certificate_free_credentials(mc.cred);
1097
gnutls_global_deinit ();
1098
gnutls_dh_params_deinit(mc.dh_params);
1099
}
1100
1101
if(gpgme_initalized){
1102
gpgme_release(mc.ctx);
1103
}
1104
1105
/* Removes the temp directory used by GPGME */
1106
if(tempdir[0] != '\0'){
1107
DIR *d;
1108
struct dirent *direntry;
1109
d = opendir(tempdir);
1110
if(d == NULL){
1111
perror("opendir");
1112
} else {
1113
while(true){
1114
direntry = readdir(d);
1115
if(direntry == NULL){
1116
break;
1117
}
1118
if (direntry->d_type == DT_REG){
1119
char *fullname = NULL;
1120
ret = asprintf(&fullname, "%s/%s", tempdir,
1121
direntry->d_name);
1122
if(ret < 0){
1123
perror("asprintf");
1124
continue;
1125
}
1126
ret = unlink(fullname);
1127
if(ret == -1){
1128
fprintf(stderr, "unlink(\"%s\"): %s",
1129
fullname, strerror(errno));
1130
}
1131
free(fullname);
1132
}
1133
}
1134
closedir(d);
1135
}
1136
ret = rmdir(tempdir);
1137
if(ret == -1){
1138
perror("rmdir");
1139
}
1140
}
1141
1142
return exitcode;
1143
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0