To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/release
« back to all changes in this revision
Viewing changes to plugins.d/mandosclient.c
- browse files at revision 1
- compare with another revision
- download diff
- download tarball
- view history from revision 1
- Committer: Björn Påhlsson
- Date: 2007-10-20 21:38:25 UTC
- Revision ID: belorn@tower-20071020213825-abf6f0d1c33ee961
First working version with: IPv6, GnuTLS, X.509 certificates, DN
retrieval.
retrieval.
- files added:
- bad-ca.pem
- files removed:
- TODO
- plugins.d
- files modified:
- Makefile
added
removed
plugins.d/mandosclient.c
1
/***
2
This file is part of avahi.
3
4
avahi is free software; you can redistribute it and/or modify it
5
under the terms of the GNU Lesser General Public License as
6
published by the Free Software Foundation; either version 2.1 of the
7
License, or (at your option) any later version.
8
9
avahi is distributed in the hope that it will be useful, but WITHOUT
10
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12
Public License for more details.
13
14
You should have received a copy of the GNU Lesser General Public
15
License along with avahi; if not, write to the Free Software
16
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
17
USA.
18
***/
19
20
#define _LARGEFILE_SOURCE
21
#define _FILE_OFFSET_BITS 64
22
23
#include <stdio.h>
24
#include <assert.h>
25
#include <stdlib.h>
26
#include <time.h>
27
#include <net/if.h> /* if_nametoindex */
28
29
#include <avahi-core/core.h>
30
#include <avahi-core/lookup.h>
31
#include <avahi-core/log.h>
32
#include <avahi-common/simple-watch.h>
33
#include <avahi-common/malloc.h>
34
#include <avahi-common/error.h>
35
36
//mandos client part
37
#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
38
#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
39
#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
40
#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
41
42
#include <unistd.h> /* close() */
43
#include <netinet/in.h>
44
#include <stdbool.h> /* true */
45
#include <string.h> /* memset */
46
#include <arpa/inet.h> /* inet_pton() */
47
#include <iso646.h> /* not */
48
49
// gpgme
50
#include <errno.h> /* perror() */
51
#include <gpgme.h>
52
53
// getopt long
54
#include <getopt.h>
55
56
#ifndef CERT_ROOT
57
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
58
#endif
59
#define CERTFILE CERT_ROOT "openpgp-client.txt"
60
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
61
#define BUFFER_SIZE 256
62
#define DH_BITS 1024
63
64
bool debug = false;
65
char *interface = "eth0";
66
67
typedef struct {
68
gnutls_session_t session;
69
gnutls_certificate_credentials_t cred;
70
gnutls_dh_params_t dh_params;
71
} encrypted_session;
72
73
74
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
75
gpgme_data_t dh_crypto, dh_plain;
76
gpgme_ctx_t ctx;
77
gpgme_error_t rc;
78
ssize_t ret;
79
size_t new_packet_capacity = 0;
80
size_t new_packet_length = 0;
81
gpgme_engine_info_t engine_info;
82
83
if (debug){
84
fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
85
}
86
87
/* Init GPGME */
88
gpgme_check_version(NULL);
89
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
90
91
/* Set GPGME home directory */
92
rc = gpgme_get_engine_info (&engine_info);
93
if (rc != GPG_ERR_NO_ERROR){
94
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
95
gpgme_strsource(rc), gpgme_strerror(rc));
96
return -1;
97
}
98
while(engine_info != NULL){
99
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
100
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
101
engine_info->file_name, homedir);
102
break;
103
}
104
engine_info = engine_info->next;
105
}
106
if(engine_info == NULL){
107
fprintf(stderr, "Could not set home dir to %s\n", homedir);
108
return -1;
109
}
110
111
/* Create new GPGME data buffer from packet buffer */
112
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
113
if (rc != GPG_ERR_NO_ERROR){
114
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
115
gpgme_strsource(rc), gpgme_strerror(rc));
116
return -1;
117
}
118
119
/* Create new empty GPGME data buffer for the plaintext */
120
rc = gpgme_data_new(&dh_plain);
121
if (rc != GPG_ERR_NO_ERROR){
122
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
123
gpgme_strsource(rc), gpgme_strerror(rc));
124
return -1;
125
}
126
127
/* Create new GPGME "context" */
128
rc = gpgme_new(&ctx);
129
if (rc != GPG_ERR_NO_ERROR){
130
fprintf(stderr, "bad gpgme_new: %s: %s\n",
131
gpgme_strsource(rc), gpgme_strerror(rc));
132
return -1;
133
}
134
135
/* Decrypt data from the FILE pointer to the plaintext data buffer */
136
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
137
if (rc != GPG_ERR_NO_ERROR){
138
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
139
gpgme_strsource(rc), gpgme_strerror(rc));
140
return -1;
141
}
142
143
if(debug){
144
fprintf(stderr, "decryption of gpg packet succeeded\n");
145
}
146
147
if (debug){
148
gpgme_decrypt_result_t result;
149
result = gpgme_op_decrypt_result(ctx);
150
if (result == NULL){
151
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
152
} else {
153
fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm);
154
fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage);
155
if(result->file_name != NULL){
156
fprintf(stderr, "File name: %s\n", result->file_name);
157
}
158
gpgme_recipient_t recipient;
159
recipient = result->recipients;
160
if(recipient){
161
while(recipient != NULL){
162
fprintf(stderr, "Public key algorithm: %s\n",
163
gpgme_pubkey_algo_name(recipient->pubkey_algo));
164
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
165
fprintf(stderr, "Secret key available: %s\n",
166
recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
167
recipient = recipient->next;
168
}
169
}
170
}
171
}
172
173
/* Delete the GPGME FILE pointer cryptotext data buffer */
174
gpgme_data_release(dh_crypto);
175
176
/* Seek back to the beginning of the GPGME plaintext data buffer */
177
gpgme_data_seek(dh_plain, 0, SEEK_SET);
178
179
*new_packet = 0;
180
while(true){
181
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
182
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
183
if (*new_packet == NULL){
184
perror("realloc");
185
return -1;
186
}
187
new_packet_capacity += BUFFER_SIZE;
188
}
189
190
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
191
/* Print the data, if any */
192
if (ret == 0){
193
/* If password is empty, then a incorrect error will be printed */
194
break;
195
}
196
if(ret < 0){
197
perror("gpgme_data_read");
198
return -1;
199
}
200
new_packet_length += ret;
201
}
202
203
/* FIXME: check characters before printing to screen so to not print
204
terminal control characters */
205
/* if(debug){ */
206
/* fprintf(stderr, "decrypted password is: "); */
207
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
208
/* fprintf(stderr, "\n"); */
209
/* } */
210
211
/* Delete the GPGME plaintext data buffer */
212
gpgme_data_release(dh_plain);
213
return new_packet_length;
214
}
215
216
static const char * safer_gnutls_strerror (int value) {
217
const char *ret = gnutls_strerror (value);
218
if (ret == NULL)
219
ret = "(unknown)";
220
return ret;
221
}
222
223
void debuggnutls(int level, const char* string){
224
fprintf(stderr, "%s", string);
225
}
226
227
int initgnutls(encrypted_session *es){
228
const char *err;
229
int ret;
230
231
if(debug){
232
fprintf(stderr, "Initializing gnutls\n");
233
}
234
235
236
if ((ret = gnutls_global_init ())
237
!= GNUTLS_E_SUCCESS) {
238
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
239
return -1;
240
}
241
242
if (debug){
243
gnutls_global_set_log_level(11);
244
gnutls_global_set_log_function(debuggnutls);
245
}
246
247
248
/* openpgp credentials */
249
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
250
!= GNUTLS_E_SUCCESS) {
251
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
252
return -1;
253
}
254
255
if(debug){
256
fprintf(stderr, "Attempting to use openpgp certificate %s"
257
" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
258
}
259
260
ret = gnutls_certificate_set_openpgp_key_file
261
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
262
if (ret != GNUTLS_E_SUCCESS) {
263
fprintf
264
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
265
ret, CERTFILE, KEYFILE);
266
fprintf(stdout, "The Error is: %s\n",
267
safer_gnutls_strerror(ret));
268
return -1;
269
}
270
271
//Gnutls server initialization
272
if ((ret = gnutls_dh_params_init (&es->dh_params))
273
!= GNUTLS_E_SUCCESS) {
274
fprintf (stderr, "Error in dh parameter initialization: %s\n",
275
safer_gnutls_strerror(ret));
276
return -1;
277
}
278
279
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
280
!= GNUTLS_E_SUCCESS) {
281
fprintf (stderr, "Error in prime generation: %s\n",
282
safer_gnutls_strerror(ret));
283
return -1;
284
}
285
286
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
287
288
// Gnutls session creation
289
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
290
!= GNUTLS_E_SUCCESS){
291
fprintf(stderr, "Error in gnutls session initialization: %s\n",
292
safer_gnutls_strerror(ret));
293
}
294
295
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
296
!= GNUTLS_E_SUCCESS) {
297
fprintf(stderr, "Syntax error at: %s\n", err);
298
fprintf(stderr, "Gnutls error: %s\n",
299
safer_gnutls_strerror(ret));
300
return -1;
301
}
302
303
if ((ret = gnutls_credentials_set
304
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
305
!= GNUTLS_E_SUCCESS) {
306
fprintf(stderr, "Error setting a credentials set: %s\n",
307
safer_gnutls_strerror(ret));
308
return -1;
309
}
310
311
/* ignore client certificate if any. */
312
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
313
314
gnutls_dh_set_prime_bits (es->session, DH_BITS);
315
316
return 0;
317
}
318
319
void empty_log(AvahiLogLevel level, const char *txt){}
320
321
int start_mandos_communication(char *ip, uint16_t port){
322
int ret, tcp_sd;
323
struct sockaddr_in6 to;
324
encrypted_session es;
325
char *buffer = NULL;
326
char *decrypted_buffer;
327
size_t buffer_length = 0;
328
size_t buffer_capacity = 0;
329
ssize_t decrypted_buffer_size;
330
int retval = 0;
331
332
if(debug){
333
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
334
}
335
336
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
337
if(tcp_sd < 0) {
338
perror("socket");
339
return -1;
340
}
341
342
if(debug){
343
fprintf(stderr, "Binding to interface %s\n", interface);
344
}
345
346
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
347
if(tcp_sd < 0) {
348
perror("setsockopt bindtodevice");
349
return -1;
350
}
351
352
memset(&to,0,sizeof(to));
353
to.sin6_family = AF_INET6;
354
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
355
if (ret < 0 ){
356
perror("inet_pton");
357
return -1;
358
}
359
if(ret == 0){
360
fprintf(stderr, "Bad address: %s\n", ip);
361
return -1;
362
}
363
to.sin6_port = htons(port);
364
to.sin6_scope_id = if_nametoindex(interface);
365
366
if(debug){
367
fprintf(stderr, "Connection to: %s\n", ip);
368
}
369
370
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
371
if (ret < 0){
372
perror("connect");
373
return -1;
374
}
375
376
ret = initgnutls (&es);
377
if (ret != 0){
378
retval = -1;
379
return -1;
380
}
381
382
383
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
384
385
if(debug){
386
fprintf(stderr, "Establishing tls session with %s\n", ip);
387
}
388
389
390
ret = gnutls_handshake (es.session);
391
392
if (ret != GNUTLS_E_SUCCESS){
393
fprintf(stderr, "\n*** Handshake failed ***\n");
394
gnutls_perror (ret);
395
retval = -1;
396
goto exit;
397
}
398
399
//Retrieve gpg packet that contains the wanted password
400
401
if(debug){
402
fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
403
}
404
405
while(true){
406
if (buffer_length + BUFFER_SIZE > buffer_capacity){
407
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
408
if (buffer == NULL){
409
perror("realloc");
410
goto exit;
411
}
412
buffer_capacity += BUFFER_SIZE;
413
}
414
415
ret = gnutls_record_recv
416
(es.session, buffer+buffer_length, BUFFER_SIZE);
417
if (ret == 0){
418
break;
419
}
420
if (ret < 0){
421
switch(ret){
422
case GNUTLS_E_INTERRUPTED:
423
case GNUTLS_E_AGAIN:
424
break;
425
case GNUTLS_E_REHANDSHAKE:
426
ret = gnutls_handshake (es.session);
427
if (ret < 0){
428
fprintf(stderr, "\n*** Handshake failed ***\n");
429
gnutls_perror (ret);
430
retval = -1;
431
goto exit;
432
}
433
break;
434
default:
435
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
436
retval = -1;
437
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
438
goto exit;
439
}
440
} else {
441
buffer_length += ret;
442
}
443
}
444
445
if (buffer_length > 0){
446
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) >= 0){
447
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
448
free(decrypted_buffer);
449
} else {
450
retval = -1;
451
}
452
}
453
454
//shutdown procedure
455
456
if(debug){
457
fprintf(stderr, "Closing tls session\n");
458
}
459
460
free(buffer);
461
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
462
exit:
463
close(tcp_sd);
464
gnutls_deinit (es.session);
465
gnutls_certificate_free_credentials (es.cred);
466
gnutls_global_deinit ();
467
return retval;
468
}
469
470
static AvahiSimplePoll *simple_poll = NULL;
471
static AvahiServer *server = NULL;
472
473
static void resolve_callback(
474
AvahiSServiceResolver *r,
475
AVAHI_GCC_UNUSED AvahiIfIndex interface,
476
AVAHI_GCC_UNUSED AvahiProtocol protocol,
477
AvahiResolverEvent event,
478
const char *name,
479
const char *type,
480
const char *domain,
481
const char *host_name,
482
const AvahiAddress *address,
483
uint16_t port,
484
AvahiStringList *txt,
485
AvahiLookupResultFlags flags,
486
AVAHI_GCC_UNUSED void* userdata) {
487
488
assert(r);
489
490
/* Called whenever a service has been resolved successfully or timed out */
491
492
switch (event) {
493
case AVAHI_RESOLVER_FAILURE:
494
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s\n", name, type, domain, avahi_strerror(avahi_server_errno(server)));
495
break;
496
497
case AVAHI_RESOLVER_FOUND: {
498
char ip[AVAHI_ADDRESS_STR_MAX];
499
avahi_address_snprint(ip, sizeof(ip), address);
500
if(debug){
501
fprintf(stderr, "Mandos server found at %s on port %d\n", ip, port);
502
}
503
int ret = start_mandos_communication(ip, port);
504
if (ret == 0){
505
exit(EXIT_SUCCESS);
506
} else {
507
exit(EXIT_FAILURE);
508
}
509
}
510
}
511
avahi_s_service_resolver_free(r);
512
}
513
514
static void browse_callback(
515
AvahiSServiceBrowser *b,
516
AvahiIfIndex interface,
517
AvahiProtocol protocol,
518
AvahiBrowserEvent event,
519
const char *name,
520
const char *type,
521
const char *domain,
522
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
523
void* userdata) {
524
525
AvahiServer *s = userdata;
526
assert(b);
527
528
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
529
530
switch (event) {
531
532
case AVAHI_BROWSER_FAILURE:
533
534
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
535
avahi_simple_poll_quit(simple_poll);
536
return;
537
538
case AVAHI_BROWSER_NEW:
539
/* We ignore the returned resolver object. In the callback
540
function we free it. If the server is terminated before
541
the callback function is called the server will free
542
the resolver for us. */
543
544
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
545
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
546
547
break;
548
549
case AVAHI_BROWSER_REMOVE:
550
break;
551
552
case AVAHI_BROWSER_ALL_FOR_NOW:
553
case AVAHI_BROWSER_CACHE_EXHAUSTED:
554
break;
555
}
556
}
557
558
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
559
AvahiServerConfig config;
560
AvahiSServiceBrowser *sb = NULL;
561
int error;
562
int ret;
563
int returncode = EXIT_SUCCESS;
564
565
while (true){
566
static struct option long_options[] = {
567
{"debug", no_argument, (int *)&debug, 1},
568
{"interface", required_argument, 0, 'i'},
569
{0, 0, 0, 0} };
570
571
int option_index = 0;
572
ret = getopt_long (argc, argv, "i:", long_options, &option_index);
573
574
if (ret == -1){
575
break;
576
}
577
578
switch(ret){
579
case 0:
580
break;
581
case 'i':
582
interface = optarg;
583
break;
584
default:
585
exit(EXIT_FAILURE);
586
}
587
}
588
589
if (not debug){
590
avahi_set_log_function(empty_log);
591
}
592
593
/* Initialize the psuedo-RNG */
594
srand(time(NULL));
595
596
/* Allocate main loop object */
597
if (!(simple_poll = avahi_simple_poll_new())) {
598
fprintf(stderr, "Failed to create simple poll object.\n");
599
600
goto exit;
601
}
602
603
/* Do not publish any local records */
604
avahi_server_config_init(&config);
605
config.publish_hinfo = 0;
606
config.publish_addresses = 0;
607
config.publish_workstation = 0;
608
config.publish_domain = 0;
609
610
/* Allocate a new server */
611
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
612
613
/* Free the configuration data */
614
avahi_server_config_free(&config);
615
616
/* Check if creating the server object succeeded */
617
if (!server) {
618
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
619
returncode = EXIT_FAILURE;
620
goto exit;
621
}
622
623
/* Create the service browser */
624
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
625
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
626
returncode = EXIT_FAILURE;
627
goto exit;
628
}
629
630
/* Run the main loop */
631
632
if (debug){
633
fprintf(stderr, "Starting avahi loop search\n");
634
}
635
636
avahi_simple_poll_loop(simple_poll);
637
638
exit:
639
640
if (debug){
641
fprintf(stderr, "%s exiting\n", argv[0]);
642
}
643
644
/* Cleanup things */
645
if (sb)
646
avahi_s_service_browser_free(sb);
647
648
if (server)
649
avahi_server_free(server);
650
651
if (simple_poll)
652
avahi_simple_poll_free(simple_poll);
653
654
return returncode;
655
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0