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- Committer: Björn Påhlsson
- Date: 2007-10-28 17:59:38 UTC
- Revision ID: belorn@tower-20071028175938-26b85eaa85b84771
Working client and server and password system
- files added:
- bad-ca.pem
- files removed:
- TODO
- plugins.d
- files modified:
- Makefile
added
removed
plugins.d/password-request.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 © 2007-2008 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() */
36
37
#include <stdio.h> /* fprintf(), stderr, fwrite(), stdout,
38
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(), memcpy(), strcpy() */
46
#include <sys/ioctl.h> /* ioctl */
47
#include <net/if.h> /* ifreq, SIOCGIFFLAGS, SIOCSIFFLAGS,
48
IFF_UP */
49
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t */
53
#include <inttypes.h> /* PRIu16 */
54
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
55
struct in6_addr, inet_pton(),
56
connect() */
57
#include <assert.h> /* assert() */
58
#include <errno.h> /* perror(), errno */
59
#include <time.h> /* time() */
60
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
61
SIOCSIFFLAGS, if_indextoname(),
62
if_nametoindex(), IF_NAMESIZE */
63
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
64
getuid(), getgid(), setuid(),
65
setgid() */
66
#include <netinet/in.h>
67
#include <arpa/inet.h> /* inet_pton(), htons */
68
#include <iso646.h> /* not, and */
69
#include <argp.h> /* struct argp_option, error_t, struct
70
argp_state, struct argp,
71
argp_parse(), ARGP_KEY_ARG,
72
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
73
74
/* Avahi */
75
/* All Avahi types, constants and functions
76
Avahi*, avahi_*,
77
AVAHI_* */
78
#include <avahi-core/core.h>
79
#include <avahi-core/lookup.h>
80
#include <avahi-core/log.h>
81
#include <avahi-common/simple-watch.h>
82
#include <avahi-common/malloc.h>
83
#include <avahi-common/error.h>
84
85
/* GnuTLS */
86
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and functions
87
gnutls_*
88
init_gnutls_session(),
89
GNUTLS_* */
90
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
91
GNUTLS_OPENPGP_FMT_BASE64 */
92
93
/* GPGME */
94
#include <gpgme.h> /* All GPGME types, constants and functions
95
gpgme_*
96
GPGME_PROTOCOL_OpenPGP,
97
GPG_ERR_NO_* */
98
99
#define BUFFER_SIZE 256
100
101
bool debug = false;
102
static const char *keydir = "/conf/conf.d/mandos";
103
static const char mandos_protocol_version[] = "1";
104
const char *argp_program_version = "password-request 1.0";
105
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
106
107
/* Used for passing in values through the Avahi callback functions */
108
typedef struct {
109
AvahiSimplePoll *simple_poll;
110
AvahiServer *server;
111
gnutls_certificate_credentials_t cred;
112
unsigned int dh_bits;
113
gnutls_dh_params_t dh_params;
114
const char *priority;
115
} mandos_context;
116
117
/*
118
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
119
* "buffer_capacity" is how much is currently allocated,
120
* "buffer_length" is how much is already used.
121
*/
122
size_t adjustbuffer(char **buffer, size_t buffer_length,
123
size_t buffer_capacity){
124
if (buffer_length + BUFFER_SIZE > buffer_capacity){
125
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
126
if (buffer == NULL){
127
return 0;
128
}
129
buffer_capacity += BUFFER_SIZE;
130
}
131
return buffer_capacity;
132
}
133
134
/*
135
* Decrypt OpenPGP data using keyrings in HOMEDIR.
136
* Returns -1 on error
137
*/
138
static ssize_t pgp_packet_decrypt (const char *cryptotext,
139
size_t crypto_size,
140
char **plaintext,
141
const char *homedir){
142
gpgme_data_t dh_crypto, dh_plain;
143
gpgme_ctx_t ctx;
144
gpgme_error_t rc;
145
ssize_t ret;
146
size_t plaintext_capacity = 0;
147
ssize_t plaintext_length = 0;
148
gpgme_engine_info_t engine_info;
149
150
if (debug){
151
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
152
}
153
154
/* Init GPGME */
155
gpgme_check_version(NULL);
156
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
157
if (rc != GPG_ERR_NO_ERROR){
158
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
159
gpgme_strsource(rc), gpgme_strerror(rc));
160
return -1;
161
}
162
163
/* Set GPGME home directory for the OpenPGP engine only */
164
rc = gpgme_get_engine_info (&engine_info);
165
if (rc != GPG_ERR_NO_ERROR){
166
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
167
gpgme_strsource(rc), gpgme_strerror(rc));
168
return -1;
169
}
170
while(engine_info != NULL){
171
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
172
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
173
engine_info->file_name, homedir);
174
break;
175
}
176
engine_info = engine_info->next;
177
}
178
if(engine_info == NULL){
179
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
180
return -1;
181
}
182
183
/* Create new GPGME data buffer from memory cryptotext */
184
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
185
0);
186
if (rc != GPG_ERR_NO_ERROR){
187
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
189
return -1;
190
}
191
192
/* Create new empty GPGME data buffer for the plaintext */
193
rc = gpgme_data_new(&dh_plain);
194
if (rc != GPG_ERR_NO_ERROR){
195
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
196
gpgme_strsource(rc), gpgme_strerror(rc));
197
gpgme_data_release(dh_crypto);
198
return -1;
199
}
200
201
/* Create new GPGME "context" */
202
rc = gpgme_new(&ctx);
203
if (rc != GPG_ERR_NO_ERROR){
204
fprintf(stderr, "bad gpgme_new: %s: %s\n",
205
gpgme_strsource(rc), gpgme_strerror(rc));
206
plaintext_length = -1;
207
goto decrypt_end;
208
}
209
210
/* Decrypt data from the cryptotext data buffer to the plaintext
211
data buffer */
212
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
213
if (rc != GPG_ERR_NO_ERROR){
214
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
215
gpgme_strsource(rc), gpgme_strerror(rc));
216
plaintext_length = -1;
217
goto decrypt_end;
218
}
219
220
if(debug){
221
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
222
}
223
224
if (debug){
225
gpgme_decrypt_result_t result;
226
result = gpgme_op_decrypt_result(ctx);
227
if (result == NULL){
228
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
229
} else {
230
fprintf(stderr, "Unsupported algorithm: %s\n",
231
result->unsupported_algorithm);
232
fprintf(stderr, "Wrong key usage: %u\n",
233
result->wrong_key_usage);
234
if(result->file_name != NULL){
235
fprintf(stderr, "File name: %s\n", result->file_name);
236
}
237
gpgme_recipient_t recipient;
238
recipient = result->recipients;
239
if(recipient){
240
while(recipient != NULL){
241
fprintf(stderr, "Public key algorithm: %s\n",
242
gpgme_pubkey_algo_name(recipient->pubkey_algo));
243
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
244
fprintf(stderr, "Secret key available: %s\n",
245
recipient->status == GPG_ERR_NO_SECKEY
246
? "No" : "Yes");
247
recipient = recipient->next;
248
}
249
}
250
}
251
}
252
253
/* Seek back to the beginning of the GPGME plaintext data buffer */
254
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
255
perror("pgpme_data_seek");
256
plaintext_length = -1;
257
goto decrypt_end;
258
}
259
260
*plaintext = NULL;
261
while(true){
262
plaintext_capacity = adjustbuffer(plaintext,
263
(size_t)plaintext_length,
264
plaintext_capacity);
265
if (plaintext_capacity == 0){
266
perror("adjustbuffer");
267
plaintext_length = -1;
268
goto decrypt_end;
269
}
270
271
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
272
BUFFER_SIZE);
273
/* Print the data, if any */
274
if (ret == 0){
275
/* EOF */
276
break;
277
}
278
if(ret < 0){
279
perror("gpgme_data_read");
280
plaintext_length = -1;
281
goto decrypt_end;
282
}
283
plaintext_length += ret;
284
}
285
286
if(debug){
287
fprintf(stderr, "Decrypted password is: ");
288
for(ssize_t i = 0; i < plaintext_length; i++){
289
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
290
}
291
fprintf(stderr, "\n");
292
}
293
294
decrypt_end:
295
296
/* Delete the GPGME cryptotext data buffer */
297
gpgme_data_release(dh_crypto);
298
299
/* Delete the GPGME plaintext data buffer */
300
gpgme_data_release(dh_plain);
301
return plaintext_length;
302
}
303
304
static const char * safer_gnutls_strerror (int value) {
305
const char *ret = gnutls_strerror (value);
306
if (ret == NULL)
307
ret = "(unknown)";
308
return ret;
309
}
310
311
/* GnuTLS log function callback */
312
static void debuggnutls(__attribute__((unused)) int level,
313
const char* string){
314
fprintf(stderr, "GnuTLS: %s", string);
315
}
316
317
static int init_gnutls_global(mandos_context *mc,
318
const char *pubkeyfile,
319
const char *seckeyfile){
320
int ret;
321
322
if(debug){
323
fprintf(stderr, "Initializing GnuTLS\n");
324
}
325
326
ret = gnutls_global_init();
327
if (ret != GNUTLS_E_SUCCESS) {
328
fprintf (stderr, "GnuTLS global_init: %s\n",
329
safer_gnutls_strerror(ret));
330
return -1;
331
}
332
333
if (debug){
334
/* "Use a log level over 10 to enable all debugging options."
335
* - GnuTLS manual
336
*/
337
gnutls_global_set_log_level(11);
338
gnutls_global_set_log_function(debuggnutls);
339
}
340
341
/* OpenPGP credentials */
342
gnutls_certificate_allocate_credentials(&mc->cred);
343
if (ret != GNUTLS_E_SUCCESS){
344
fprintf (stderr, "GnuTLS memory error: %s\n",
345
safer_gnutls_strerror(ret));
346
gnutls_global_deinit ();
347
return -1;
348
}
349
350
if(debug){
351
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
352
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
353
seckeyfile);
354
}
355
356
ret = gnutls_certificate_set_openpgp_key_file
357
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
358
if (ret != GNUTLS_E_SUCCESS) {
359
fprintf(stderr,
360
"Error[%d] while reading the OpenPGP key pair ('%s',"
361
" '%s')\n", ret, pubkeyfile, seckeyfile);
362
fprintf(stdout, "The GnuTLS error is: %s\n",
363
safer_gnutls_strerror(ret));
364
goto globalfail;
365
}
366
367
/* GnuTLS server initialization */
368
ret = gnutls_dh_params_init(&mc->dh_params);
369
if (ret != GNUTLS_E_SUCCESS) {
370
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
371
" %s\n", safer_gnutls_strerror(ret));
372
goto globalfail;
373
}
374
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
375
if (ret != GNUTLS_E_SUCCESS) {
376
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
377
safer_gnutls_strerror(ret));
378
goto globalfail;
379
}
380
381
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
382
383
return 0;
384
385
globalfail:
386
387
gnutls_certificate_free_credentials(mc->cred);
388
gnutls_global_deinit();
389
return -1;
390
391
}
392
393
static int init_gnutls_session(mandos_context *mc,
394
gnutls_session_t *session){
395
int ret;
396
/* GnuTLS session creation */
397
ret = gnutls_init(session, GNUTLS_SERVER);
398
if (ret != GNUTLS_E_SUCCESS){
399
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
400
safer_gnutls_strerror(ret));
401
}
402
403
{
404
const char *err;
405
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
406
if (ret != GNUTLS_E_SUCCESS) {
407
fprintf(stderr, "Syntax error at: %s\n", err);
408
fprintf(stderr, "GnuTLS error: %s\n",
409
safer_gnutls_strerror(ret));
410
gnutls_deinit (*session);
411
return -1;
412
}
413
}
414
415
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
416
mc->cred);
417
if (ret != GNUTLS_E_SUCCESS) {
418
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
419
safer_gnutls_strerror(ret));
420
gnutls_deinit (*session);
421
return -1;
422
}
423
424
/* ignore client certificate if any. */
425
gnutls_certificate_server_set_request (*session,
426
GNUTLS_CERT_IGNORE);
427
428
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
429
430
return 0;
431
}
432
433
/* Avahi log function callback */
434
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
435
__attribute__((unused)) const char *txt){}
436
437
/* Called when a Mandos server is found */
438
static int start_mandos_communication(const char *ip, uint16_t port,
439
AvahiIfIndex if_index,
440
mandos_context *mc){
441
int ret, tcp_sd;
442
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
443
char *buffer = NULL;
444
char *decrypted_buffer;
445
size_t buffer_length = 0;
446
size_t buffer_capacity = 0;
447
ssize_t decrypted_buffer_size;
448
size_t written;
449
int retval = 0;
450
char interface[IF_NAMESIZE];
451
gnutls_session_t session;
452
453
ret = init_gnutls_session (mc, &session);
454
if (ret != 0){
455
return -1;
456
}
457
458
if(debug){
459
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
460
"\n", ip, port);
461
}
462
463
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
464
if(tcp_sd < 0) {
465
perror("socket");
466
return -1;
467
}
468
469
if(debug){
470
if(if_indextoname((unsigned int)if_index, interface) == NULL){
471
perror("if_indextoname");
472
return -1;
473
}
474
fprintf(stderr, "Binding to interface %s\n", interface);
475
}
476
477
memset(&to,0,sizeof(to)); /* Spurious warning */
478
to.in6.sin6_family = AF_INET6;
479
/* It would be nice to have a way to detect if we were passed an
480
IPv4 address here. Now we assume an IPv6 address. */
481
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
482
if (ret < 0 ){
483
perror("inet_pton");
484
return -1;
485
}
486
if(ret == 0){
487
fprintf(stderr, "Bad address: %s\n", ip);
488
return -1;
489
}
490
to.in6.sin6_port = htons(port); /* Spurious warning */
491
492
to.in6.sin6_scope_id = (uint32_t)if_index;
493
494
if(debug){
495
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
496
port);
497
char addrstr[INET6_ADDRSTRLEN] = "";
498
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
499
sizeof(addrstr)) == NULL){
500
perror("inet_ntop");
501
} else {
502
if(strcmp(addrstr, ip) != 0){
503
fprintf(stderr, "Canonical address form: %s\n", addrstr);
504
}
505
}
506
}
507
508
ret = connect(tcp_sd, &to.in, sizeof(to));
509
if (ret < 0){
510
perror("connect");
511
return -1;
512
}
513
514
const char *out = mandos_protocol_version;
515
written = 0;
516
while (true){
517
size_t out_size = strlen(out);
518
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
519
out_size - written));
520
if (ret == -1){
521
perror("write");
522
retval = -1;
523
goto mandos_end;
524
}
525
written += (size_t)ret;
526
if(written < out_size){
527
continue;
528
} else {
529
if (out == mandos_protocol_version){
530
written = 0;
531
out = "\r\n";
532
} else {
533
break;
534
}
535
}
536
}
537
538
if(debug){
539
fprintf(stderr, "Establishing TLS session with %s\n", ip);
540
}
541
542
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
543
544
do{
545
ret = gnutls_handshake (session);
546
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
547
548
if (ret != GNUTLS_E_SUCCESS){
549
if(debug){
550
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
551
gnutls_perror (ret);
552
}
553
retval = -1;
554
goto mandos_end;
555
}
556
557
/* Read OpenPGP packet that contains the wanted password */
558
559
if(debug){
560
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
561
ip);
562
}
563
564
while(true){
565
buffer_capacity = adjustbuffer(&buffer, buffer_length,
566
buffer_capacity);
567
if (buffer_capacity == 0){
568
perror("adjustbuffer");
569
retval = -1;
570
goto mandos_end;
571
}
572
573
ret = gnutls_record_recv(session, buffer+buffer_length,
574
BUFFER_SIZE);
575
if (ret == 0){
576
break;
577
}
578
if (ret < 0){
579
switch(ret){
580
case GNUTLS_E_INTERRUPTED:
581
case GNUTLS_E_AGAIN:
582
break;
583
case GNUTLS_E_REHANDSHAKE:
584
do{
585
ret = gnutls_handshake (session);
586
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
587
if (ret < 0){
588
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
589
gnutls_perror (ret);
590
retval = -1;
591
goto mandos_end;
592
}
593
break;
594
default:
595
fprintf(stderr, "Unknown error while reading data from"
596
" encrypted session with Mandos server\n");
597
retval = -1;
598
gnutls_bye (session, GNUTLS_SHUT_RDWR);
599
goto mandos_end;
600
}
601
} else {
602
buffer_length += (size_t) ret;
603
}
604
}
605
606
if(debug){
607
fprintf(stderr, "Closing TLS session\n");
608
}
609
610
gnutls_bye (session, GNUTLS_SHUT_RDWR);
611
612
if (buffer_length > 0){
613
decrypted_buffer_size = pgp_packet_decrypt(buffer,
614
buffer_length,
615
&decrypted_buffer,
616
keydir);
617
if (decrypted_buffer_size >= 0){
618
written = 0;
619
while(written < (size_t) decrypted_buffer_size){
620
ret = (int)fwrite (decrypted_buffer + written, 1,
621
(size_t)decrypted_buffer_size - written,
622
stdout);
623
if(ret == 0 and ferror(stdout)){
624
if(debug){
625
fprintf(stderr, "Error writing encrypted data: %s\n",
626
strerror(errno));
627
}
628
retval = -1;
629
break;
630
}
631
written += (size_t)ret;
632
}
633
free(decrypted_buffer);
634
} else {
635
retval = -1;
636
}
637
}
638
639
/* Shutdown procedure */
640
641
mandos_end:
642
free(buffer);
643
close(tcp_sd);
644
gnutls_deinit (session);
645
return retval;
646
}
647
648
static void resolve_callback(AvahiSServiceResolver *r,
649
AvahiIfIndex interface,
650
AVAHI_GCC_UNUSED AvahiProtocol protocol,
651
AvahiResolverEvent event,
652
const char *name,
653
const char *type,
654
const char *domain,
655
const char *host_name,
656
const AvahiAddress *address,
657
uint16_t port,
658
AVAHI_GCC_UNUSED AvahiStringList *txt,
659
AVAHI_GCC_UNUSED AvahiLookupResultFlags
660
flags,
661
void* userdata) {
662
mandos_context *mc = userdata;
663
assert(r); /* Spurious warning */
664
665
/* Called whenever a service has been resolved successfully or
666
timed out */
667
668
switch (event) {
669
default:
670
case AVAHI_RESOLVER_FAILURE:
671
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
672
" of type '%s' in domain '%s': %s\n", name, type, domain,
673
avahi_strerror(avahi_server_errno(mc->server)));
674
break;
675
676
case AVAHI_RESOLVER_FOUND:
677
{
678
char ip[AVAHI_ADDRESS_STR_MAX];
679
avahi_address_snprint(ip, sizeof(ip), address);
680
if(debug){
681
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
682
PRIu16 ") on port %d\n", name, host_name, ip,
683
interface, port);
684
}
685
int ret = start_mandos_communication(ip, port, interface, mc);
686
if (ret == 0){
687
exit(EXIT_SUCCESS);
688
}
689
}
690
}
691
avahi_s_service_resolver_free(r);
692
}
693
694
static void browse_callback( AvahiSServiceBrowser *b,
695
AvahiIfIndex interface,
696
AvahiProtocol protocol,
697
AvahiBrowserEvent event,
698
const char *name,
699
const char *type,
700
const char *domain,
701
AVAHI_GCC_UNUSED AvahiLookupResultFlags
702
flags,
703
void* userdata) {
704
mandos_context *mc = userdata;
705
assert(b); /* Spurious warning */
706
707
/* Called whenever a new services becomes available on the LAN or
708
is removed from the LAN */
709
710
switch (event) {
711
default:
712
case AVAHI_BROWSER_FAILURE:
713
714
fprintf(stderr, "(Avahi browser) %s\n",
715
avahi_strerror(avahi_server_errno(mc->server)));
716
avahi_simple_poll_quit(mc->simple_poll);
717
return;
718
719
case AVAHI_BROWSER_NEW:
720
/* We ignore the returned Avahi resolver object. In the callback
721
function we free it. If the Avahi server is terminated before
722
the callback function is called the Avahi server will free the
723
resolver for us. */
724
725
if (!(avahi_s_service_resolver_new(mc->server, interface,
726
protocol, name, type, domain,
727
AVAHI_PROTO_INET6, 0,
728
resolve_callback, mc)))
729
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
730
name, avahi_strerror(avahi_server_errno(mc->server)));
731
break;
732
733
case AVAHI_BROWSER_REMOVE:
734
break;
735
736
case AVAHI_BROWSER_ALL_FOR_NOW:
737
case AVAHI_BROWSER_CACHE_EXHAUSTED:
738
if(debug){
739
fprintf(stderr, "No Mandos server found, still searching...\n");
740
}
741
break;
742
}
743
}
744
745
/* Combines file name and path and returns the malloced new
746
string. some sane checks could/should be added */
747
static const char *combinepath(const char *first, const char *second){
748
size_t f_len = strlen(first);
749
size_t s_len = strlen(second);
750
char *tmp = malloc(f_len + s_len + 2);
751
if (tmp == NULL){
752
return NULL;
753
}
754
if(f_len > 0){
755
memcpy(tmp, first, f_len); /* Spurious warning */
756
}
757
tmp[f_len] = '/';
758
if(s_len > 0){
759
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
760
}
761
tmp[f_len + 1 + s_len] = '\0';
762
return tmp;
763
}
764
765
766
int main(int argc, char *argv[]){
767
AvahiSServiceBrowser *sb = NULL;
768
int error;
769
int ret;
770
int exitcode = EXIT_SUCCESS;
771
const char *interface = "eth0";
772
struct ifreq network;
773
int sd;
774
uid_t uid;
775
gid_t gid;
776
char *connect_to = NULL;
777
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
778
const char *pubkeyfile = "pubkey.txt";
779
const char *seckeyfile = "seckey.txt";
780
mandos_context mc = { .simple_poll = NULL, .server = NULL,
781
.dh_bits = 1024, .priority = "SECURE256"};
782
bool gnutls_initalized = false;
783
784
{
785
struct argp_option options[] = {
786
{ .name = "debug", .key = 128,
787
.doc = "Debug mode", .group = 3 },
788
{ .name = "connect", .key = 'c',
789
.arg = "IP",
790
.doc = "Connect directly to a sepcified mandos server",
791
.group = 1 },
792
{ .name = "interface", .key = 'i',
793
.arg = "INTERFACE",
794
.doc = "Interface that Avahi will conntect through",
795
.group = 1 },
796
{ .name = "keydir", .key = 'd',
797
.arg = "KEYDIR",
798
.doc = "Directory where the openpgp keyring is",
799
.group = 1 },
800
{ .name = "seckey", .key = 's',
801
.arg = "SECKEY",
802
.doc = "Secret openpgp key for gnutls authentication",
803
.group = 1 },
804
{ .name = "pubkey", .key = 'p',
805
.arg = "PUBKEY",
806
.doc = "Public openpgp key for gnutls authentication",
807
.group = 2 },
808
{ .name = "dh-bits", .key = 129,
809
.arg = "BITS",
810
.doc = "dh-bits to use in gnutls communication",
811
.group = 2 },
812
{ .name = "priority", .key = 130,
813
.arg = "PRIORITY",
814
.doc = "GNUTLS priority", .group = 1 },
815
{ .name = NULL }
816
};
817
818
819
error_t parse_opt (int key, char *arg,
820
struct argp_state *state) {
821
/* Get the INPUT argument from `argp_parse', which we know is
822
a pointer to our plugin list pointer. */
823
switch (key) {
824
case 128:
825
debug = true;
826
break;
827
case 'c':
828
connect_to = arg;
829
break;
830
case 'i':
831
interface = arg;
832
break;
833
case 'd':
834
keydir = arg;
835
break;
836
case 's':
837
seckeyfile = arg;
838
break;
839
case 'p':
840
pubkeyfile = arg;
841
break;
842
case 129:
843
errno = 0;
844
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
845
if (errno){
846
perror("strtol");
847
exit(EXIT_FAILURE);
848
}
849
break;
850
case 130:
851
mc.priority = arg;
852
break;
853
case ARGP_KEY_ARG:
854
argp_usage (state);
855
break;
856
case ARGP_KEY_END:
857
break;
858
default:
859
return ARGP_ERR_UNKNOWN;
860
}
861
return 0;
862
}
863
864
struct argp argp = { .options = options, .parser = parse_opt,
865
.args_doc = "",
866
.doc = "Mandos client -- Get and decrypt"
867
" passwords from mandos server" };
868
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
869
if (ret == ARGP_ERR_UNKNOWN){
870
fprintf(stderr, "Unkown error while parsing arguments\n");
871
exitcode = EXIT_FAILURE;
872
goto end;
873
}
874
}
875
876
pubkeyfile = combinepath(keydir, pubkeyfile);
877
if (pubkeyfile == NULL){
878
perror("combinepath");
879
exitcode = EXIT_FAILURE;
880
goto end;
881
}
882
883
seckeyfile = combinepath(keydir, seckeyfile);
884
if (seckeyfile == NULL){
885
perror("combinepath");
886
goto end;
887
}
888
889
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
890
if (ret == -1){
891
fprintf(stderr, "init_gnutls_global\n");
892
goto end;
893
} else {
894
gnutls_initalized = true;
895
}
896
897
uid = getuid();
898
gid = getgid();
899
900
ret = setuid(uid);
901
if (ret == -1){
902
perror("setuid");
903
}
904
905
setgid(gid);
906
if (ret == -1){
907
perror("setgid");
908
}
909
910
if_index = (AvahiIfIndex) if_nametoindex(interface);
911
if(if_index == 0){
912
fprintf(stderr, "No such interface: \"%s\"\n", interface);
913
exit(EXIT_FAILURE);
914
}
915
916
if(connect_to != NULL){
917
/* Connect directly, do not use Zeroconf */
918
/* (Mainly meant for debugging) */
919
char *address = strrchr(connect_to, ':');
920
if(address == NULL){
921
fprintf(stderr, "No colon in address\n");
922
exitcode = EXIT_FAILURE;
923
goto end;
924
}
925
errno = 0;
926
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
927
if(errno){
928
perror("Bad port number");
929
exitcode = EXIT_FAILURE;
930
goto end;
931
}
932
*address = '\0';
933
address = connect_to;
934
ret = start_mandos_communication(address, port, if_index, &mc);
935
if(ret < 0){
936
exitcode = EXIT_FAILURE;
937
} else {
938
exitcode = EXIT_SUCCESS;
939
}
940
goto end;
941
}
942
943
/* If the interface is down, bring it up */
944
{
945
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
946
if(sd < 0) {
947
perror("socket");
948
exitcode = EXIT_FAILURE;
949
goto end;
950
}
951
strcpy(network.ifr_name, interface); /* Spurious warning */
952
ret = ioctl(sd, SIOCGIFFLAGS, &network);
953
if(ret == -1){
954
perror("ioctl SIOCGIFFLAGS");
955
exitcode = EXIT_FAILURE;
956
goto end;
957
}
958
if((network.ifr_flags & IFF_UP) == 0){
959
network.ifr_flags |= IFF_UP;
960
ret = ioctl(sd, SIOCSIFFLAGS, &network);
961
if(ret == -1){
962
perror("ioctl SIOCSIFFLAGS");
963
exitcode = EXIT_FAILURE;
964
goto end;
965
}
966
}
967
close(sd);
968
}
969
970
if (not debug){
971
avahi_set_log_function(empty_log);
972
}
973
974
/* Initialize the pseudo-RNG for Avahi */
975
srand((unsigned int) time(NULL));
976
977
/* Allocate main Avahi loop object */
978
mc.simple_poll = avahi_simple_poll_new();
979
if (mc.simple_poll == NULL) {
980
fprintf(stderr, "Avahi: Failed to create simple poll"
981
" object.\n");
982
exitcode = EXIT_FAILURE;
983
goto end;
984
}
985
986
{
987
AvahiServerConfig config;
988
/* Do not publish any local Zeroconf records */
989
avahi_server_config_init(&config);
990
config.publish_hinfo = 0;
991
config.publish_addresses = 0;
992
config.publish_workstation = 0;
993
config.publish_domain = 0;
994
995
/* Allocate a new server */
996
mc.server = avahi_server_new(avahi_simple_poll_get
997
(mc.simple_poll), &config, NULL,
998
NULL, &error);
999
1000
/* Free the Avahi configuration data */
1001
avahi_server_config_free(&config);
1002
}
1003
1004
/* Check if creating the Avahi server object succeeded */
1005
if (mc.server == NULL) {
1006
fprintf(stderr, "Failed to create Avahi server: %s\n",
1007
avahi_strerror(error));
1008
exitcode = EXIT_FAILURE;
1009
goto end;
1010
}
1011
1012
/* Create the Avahi service browser */
1013
sb = avahi_s_service_browser_new(mc.server, if_index,
1014
AVAHI_PROTO_INET6,
1015
"_mandos._tcp", NULL, 0,
1016
browse_callback, &mc);
1017
if (sb == NULL) {
1018
fprintf(stderr, "Failed to create service browser: %s\n",
1019
avahi_strerror(avahi_server_errno(mc.server)));
1020
exitcode = EXIT_FAILURE;
1021
goto end;
1022
}
1023
1024
/* Run the main loop */
1025
1026
if (debug){
1027
fprintf(stderr, "Starting Avahi loop search\n");
1028
}
1029
1030
avahi_simple_poll_loop(mc.simple_poll);
1031
1032
end:
1033
1034
if (debug){
1035
fprintf(stderr, "%s exiting\n", argv[0]);
1036
}
1037
1038
/* Cleanup things */
1039
if (sb != NULL)
1040
avahi_s_service_browser_free(sb);
1041
1042
if (mc.server != NULL)
1043
avahi_server_free(mc.server);
1044
1045
if (mc.simple_poll != NULL)
1046
avahi_simple_poll_free(mc.simple_poll);
1047
free(pubkeyfile);
1048
free(seckeyfile);
1049
1050
if (gnutls_initalized){
1051
gnutls_certificate_free_credentials(mc.cred);
1052
gnutls_global_deinit ();
1053
}
1054
1055
return exitcode;
1056
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0