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- Committer: Teddy Hogeborn
- Date: 2008-09-03 17:34:29 UTC
- Revision ID: teddy@fukt.bsnet.se-20080903173429-db2mjtddf7mgbx8z
* plugins.d/password-request.xml (OVERVIEW): Refer to
password-prompt(8) by
name.
(SECURITY): Improved wording. Add paragraph about insecurity of
ping.
(SEE ALSO): Add references to cryptsetup(8) and crypttab(5).
Changed to be a <variablelist> and added text.
password-prompt(8) by
name.
(SECURITY): Improved wording. Add paragraph about insecurity of
ping.
(SEE ALSO): Add references to cryptsetup(8) and crypttab(5).
Changed to be a <variablelist> and added text.
- files added:
- .bzrignore
- plugins.d
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- 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(), 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 */
51
#include <inttypes.h> /* PRIu16 */
52
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
53
struct in6_addr, inet_pton(),
54
connect() */
55
#include <assert.h> /* assert() */
56
#include <errno.h> /* perror(), errno */
57
#include <time.h> /* time() */
58
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
59
SIOCSIFFLAGS, if_indextoname(),
60
if_nametoindex(), IF_NAMESIZE */
61
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
62
getuid(), getgid(), setuid(),
63
setgid() */
64
#include <netinet/in.h>
65
#include <arpa/inet.h> /* inet_pton(), htons */
66
#include <iso646.h> /* not, and */
67
#include <argp.h> /* struct argp_option, error_t, struct
68
argp_state, struct argp,
69
argp_parse(), ARGP_KEY_ARG,
70
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
71
72
/* Avahi */
73
/* All Avahi types, constants and functions
74
Avahi*, avahi_*,
75
AVAHI_* */
76
#include <avahi-core/core.h>
77
#include <avahi-core/lookup.h>
78
#include <avahi-core/log.h>
79
#include <avahi-common/simple-watch.h>
80
#include <avahi-common/malloc.h>
81
#include <avahi-common/error.h>
82
83
/* GnuTLS */
84
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
85
functions:
86
gnutls_*
87
init_gnutls_session(),
88
GNUTLS_* */
89
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
90
GNUTLS_OPENPGP_FMT_BASE64 */
91
92
/* GPGME */
93
#include <gpgme.h> /* All GPGME types, constants and
94
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
if (debug){
218
gpgme_decrypt_result_t result;
219
result = gpgme_op_decrypt_result(ctx);
220
if (result == NULL){
221
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
222
} else {
223
fprintf(stderr, "Unsupported algorithm: %s\n",
224
result->unsupported_algorithm);
225
fprintf(stderr, "Wrong key usage: %u\n",
226
result->wrong_key_usage);
227
if(result->file_name != NULL){
228
fprintf(stderr, "File name: %s\n", result->file_name);
229
}
230
gpgme_recipient_t recipient;
231
recipient = result->recipients;
232
if(recipient){
233
while(recipient != NULL){
234
fprintf(stderr, "Public key algorithm: %s\n",
235
gpgme_pubkey_algo_name(recipient->pubkey_algo));
236
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
237
fprintf(stderr, "Secret key available: %s\n",
238
recipient->status == GPG_ERR_NO_SECKEY
239
? "No" : "Yes");
240
recipient = recipient->next;
241
}
242
}
243
}
244
}
245
goto decrypt_end;
246
}
247
248
if(debug){
249
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
250
}
251
252
/* Seek back to the beginning of the GPGME plaintext data buffer */
253
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
254
perror("pgpme_data_seek");
255
plaintext_length = -1;
256
goto decrypt_end;
257
}
258
259
*plaintext = NULL;
260
while(true){
261
plaintext_capacity = adjustbuffer(plaintext,
262
(size_t)plaintext_length,
263
plaintext_capacity);
264
if (plaintext_capacity == 0){
265
perror("adjustbuffer");
266
plaintext_length = -1;
267
goto decrypt_end;
268
}
269
270
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
271
BUFFER_SIZE);
272
/* Print the data, if any */
273
if (ret == 0){
274
/* EOF */
275
break;
276
}
277
if(ret < 0){
278
perror("gpgme_data_read");
279
plaintext_length = -1;
280
goto decrypt_end;
281
}
282
plaintext_length += ret;
283
}
284
285
if(debug){
286
fprintf(stderr, "Decrypted password is: ");
287
for(ssize_t i = 0; i < plaintext_length; i++){
288
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
289
}
290
fprintf(stderr, "\n");
291
}
292
293
decrypt_end:
294
295
/* Delete the GPGME cryptotext data buffer */
296
gpgme_data_release(dh_crypto);
297
298
/* Delete the GPGME plaintext data buffer */
299
gpgme_data_release(dh_plain);
300
return plaintext_length;
301
}
302
303
static const char * safer_gnutls_strerror (int value) {
304
const char *ret = gnutls_strerror (value); /* Spurious warning */
305
if (ret == NULL)
306
ret = "(unknown)";
307
return ret;
308
}
309
310
/* GnuTLS log function callback */
311
static void debuggnutls(__attribute__((unused)) int level,
312
const char* string){
313
fprintf(stderr, "GnuTLS: %s", string);
314
}
315
316
static int init_gnutls_global(mandos_context *mc,
317
const char *pubkeyfilename,
318
const char *seckeyfilename){
319
int ret;
320
321
if(debug){
322
fprintf(stderr, "Initializing GnuTLS\n");
323
}
324
325
ret = gnutls_global_init();
326
if (ret != GNUTLS_E_SUCCESS) {
327
fprintf (stderr, "GnuTLS global_init: %s\n",
328
safer_gnutls_strerror(ret));
329
return -1;
330
}
331
332
if (debug){
333
/* "Use a log level over 10 to enable all debugging options."
334
* - GnuTLS manual
335
*/
336
gnutls_global_set_log_level(11);
337
gnutls_global_set_log_function(debuggnutls);
338
}
339
340
/* OpenPGP credentials */
341
gnutls_certificate_allocate_credentials(&mc->cred);
342
if (ret != GNUTLS_E_SUCCESS){
343
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
344
warning */
345
safer_gnutls_strerror(ret));
346
gnutls_global_deinit ();
347
return -1;
348
}
349
350
if(debug){
351
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
352
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
353
seckeyfilename);
354
}
355
356
ret = gnutls_certificate_set_openpgp_key_file
357
(mc->cred, pubkeyfilename, seckeyfilename,
358
GNUTLS_OPENPGP_FMT_BASE64);
359
if (ret != GNUTLS_E_SUCCESS) {
360
fprintf(stderr,
361
"Error[%d] while reading the OpenPGP key pair ('%s',"
362
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
363
fprintf(stderr, "The GnuTLS error is: %s\n",
364
safer_gnutls_strerror(ret));
365
goto globalfail;
366
}
367
368
/* GnuTLS server initialization */
369
ret = gnutls_dh_params_init(&mc->dh_params);
370
if (ret != GNUTLS_E_SUCCESS) {
371
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
372
" %s\n", safer_gnutls_strerror(ret));
373
goto globalfail;
374
}
375
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
376
if (ret != GNUTLS_E_SUCCESS) {
377
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
378
safer_gnutls_strerror(ret));
379
goto globalfail;
380
}
381
382
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
383
384
return 0;
385
386
globalfail:
387
388
gnutls_certificate_free_credentials(mc->cred);
389
gnutls_global_deinit();
390
return -1;
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));
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
} else {
638
retval = -1;
639
}
640
641
/* Shutdown procedure */
642
643
mandos_end:
644
free(buffer);
645
close(tcp_sd);
646
gnutls_deinit (session);
647
return retval;
648
}
649
650
static void resolve_callback(AvahiSServiceResolver *r,
651
AvahiIfIndex interface,
652
AVAHI_GCC_UNUSED AvahiProtocol protocol,
653
AvahiResolverEvent event,
654
const char *name,
655
const char *type,
656
const char *domain,
657
const char *host_name,
658
const AvahiAddress *address,
659
uint16_t port,
660
AVAHI_GCC_UNUSED AvahiStringList *txt,
661
AVAHI_GCC_UNUSED AvahiLookupResultFlags
662
flags,
663
void* userdata) {
664
mandos_context *mc = userdata;
665
assert(r);
666
667
/* Called whenever a service has been resolved successfully or
668
timed out */
669
670
switch (event) {
671
default:
672
case AVAHI_RESOLVER_FAILURE:
673
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
674
" of type '%s' in domain '%s': %s\n", name, type, domain,
675
avahi_strerror(avahi_server_errno(mc->server)));
676
break;
677
678
case AVAHI_RESOLVER_FOUND:
679
{
680
char ip[AVAHI_ADDRESS_STR_MAX];
681
avahi_address_snprint(ip, sizeof(ip), address);
682
if(debug){
683
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
684
PRIu16 ") on port %d\n", name, host_name, ip,
685
interface, port);
686
}
687
int ret = start_mandos_communication(ip, port, interface, mc);
688
if (ret == 0){
689
avahi_simple_poll_quit(mc->simple_poll);
690
}
691
}
692
}
693
avahi_s_service_resolver_free(r);
694
}
695
696
static void browse_callback( AvahiSServiceBrowser *b,
697
AvahiIfIndex interface,
698
AvahiProtocol protocol,
699
AvahiBrowserEvent event,
700
const char *name,
701
const char *type,
702
const char *domain,
703
AVAHI_GCC_UNUSED AvahiLookupResultFlags
704
flags,
705
void* userdata) {
706
mandos_context *mc = userdata;
707
assert(b);
708
709
/* Called whenever a new services becomes available on the LAN or
710
is removed from the LAN */
711
712
switch (event) {
713
default:
714
case AVAHI_BROWSER_FAILURE:
715
716
fprintf(stderr, "(Avahi browser) %s\n",
717
avahi_strerror(avahi_server_errno(mc->server)));
718
avahi_simple_poll_quit(mc->simple_poll);
719
return;
720
721
case AVAHI_BROWSER_NEW:
722
/* We ignore the returned Avahi resolver object. In the callback
723
function we free it. If the Avahi server is terminated before
724
the callback function is called the Avahi server will free the
725
resolver for us. */
726
727
if (!(avahi_s_service_resolver_new(mc->server, interface,
728
protocol, name, type, domain,
729
AVAHI_PROTO_INET6, 0,
730
resolve_callback, mc)))
731
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
732
name, avahi_strerror(avahi_server_errno(mc->server)));
733
break;
734
735
case AVAHI_BROWSER_REMOVE:
736
break;
737
738
case AVAHI_BROWSER_ALL_FOR_NOW:
739
case AVAHI_BROWSER_CACHE_EXHAUSTED:
740
if(debug){
741
fprintf(stderr, "No Mandos server found, still searching...\n");
742
}
743
break;
744
}
745
}
746
747
/* Combines file name and path and returns the malloced new
748
string. some sane checks could/should be added */
749
static char *combinepath(const char *first, const char *second){
750
char *tmp;
751
int ret = asprintf(&tmp, "%s/%s", first, second);
752
if(ret < 0){
753
return NULL;
754
}
755
return tmp;
756
}
757
758
759
int main(int argc, char *argv[]){
760
AvahiSServiceBrowser *sb = NULL;
761
int error;
762
int ret;
763
int exitcode = EXIT_SUCCESS;
764
const char *interface = "eth0";
765
struct ifreq network;
766
int sd;
767
uid_t uid;
768
gid_t gid;
769
char *connect_to = NULL;
770
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
771
char *pubkeyfilename = NULL;
772
char *seckeyfilename = NULL;
773
const char *pubkeyname = "pubkey.txt";
774
const char *seckeyname = "seckey.txt";
775
mandos_context mc = { .simple_poll = NULL, .server = NULL,
776
.dh_bits = 1024, .priority = "SECURE256"
777
":!CTYPE-X.509:+CTYPE-OPENPGP" };
778
bool gnutls_initalized = false;
779
780
{
781
struct argp_option options[] = {
782
{ .name = "debug", .key = 128,
783
.doc = "Debug mode", .group = 3 },
784
{ .name = "connect", .key = 'c',
785
.arg = "ADDRESS:PORT",
786
.doc = "Connect directly to a specific Mandos server",
787
.group = 1 },
788
{ .name = "interface", .key = 'i',
789
.arg = "NAME",
790
.doc = "Interface that will be used to search for Mandos"
791
" servers",
792
.group = 1 },
793
{ .name = "keydir", .key = 'd',
794
.arg = "DIRECTORY",
795
.doc = "Directory to read the OpenPGP key files from",
796
.group = 1 },
797
{ .name = "seckey", .key = 's',
798
.arg = "FILE",
799
.doc = "OpenPGP secret key file base name",
800
.group = 1 },
801
{ .name = "pubkey", .key = 'p',
802
.arg = "FILE",
803
.doc = "OpenPGP public key file base name",
804
.group = 2 },
805
{ .name = "dh-bits", .key = 129,
806
.arg = "BITS",
807
.doc = "Bit length of the prime number used in the"
808
" Diffie-Hellman key exchange",
809
.group = 2 },
810
{ .name = "priority", .key = 130,
811
.arg = "STRING",
812
.doc = "GnuTLS priority string for the TLS handshake",
813
.group = 1 },
814
{ .name = NULL }
815
};
816
817
error_t parse_opt (int key, char *arg,
818
struct argp_state *state) {
819
/* Get the INPUT argument from `argp_parse', which we know is
820
a pointer to our plugin list pointer. */
821
switch (key) {
822
case 128: /* --debug */
823
debug = true;
824
break;
825
case 'c': /* --connect */
826
connect_to = arg;
827
break;
828
case 'i': /* --interface */
829
interface = arg;
830
break;
831
case 'd': /* --keydir */
832
keydir = arg;
833
break;
834
case 's': /* --seckey */
835
seckeyname = arg;
836
break;
837
case 'p': /* --pubkey */
838
pubkeyname = arg;
839
break;
840
case 129: /* --dh-bits */
841
errno = 0;
842
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
843
if (errno){
844
perror("strtol");
845
exit(EXIT_FAILURE);
846
}
847
break;
848
case 130: /* --priority */
849
mc.priority = arg;
850
break;
851
case ARGP_KEY_ARG:
852
argp_usage (state);
853
case ARGP_KEY_END:
854
break;
855
default:
856
return ARGP_ERR_UNKNOWN;
857
}
858
return 0;
859
}
860
861
struct argp argp = { .options = options, .parser = parse_opt,
862
.args_doc = "",
863
.doc = "Mandos client -- Get and decrypt"
864
" passwords from a Mandos server" };
865
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
866
if (ret == ARGP_ERR_UNKNOWN){
867
fprintf(stderr, "Unknown error while parsing arguments\n");
868
exitcode = EXIT_FAILURE;
869
goto end;
870
}
871
}
872
873
pubkeyfilename = combinepath(keydir, pubkeyname);
874
if (pubkeyfilename == NULL){
875
perror("combinepath");
876
exitcode = EXIT_FAILURE;
877
goto end;
878
}
879
880
seckeyfilename = combinepath(keydir, seckeyname);
881
if (seckeyfilename == NULL){
882
perror("combinepath");
883
exitcode = EXIT_FAILURE;
884
goto end;
885
}
886
887
ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);
888
if (ret == -1){
889
fprintf(stderr, "init_gnutls_global failed\n");
890
exitcode = EXIT_FAILURE;
891
goto end;
892
} else {
893
gnutls_initalized = true;
894
}
895
896
/* If the interface is down, bring it up */
897
{
898
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
899
if(sd < 0) {
900
perror("socket");
901
exitcode = EXIT_FAILURE;
902
goto end;
903
}
904
strcpy(network.ifr_name, interface);
905
ret = ioctl(sd, SIOCGIFFLAGS, &network);
906
if(ret == -1){
907
perror("ioctl SIOCGIFFLAGS");
908
exitcode = EXIT_FAILURE;
909
goto end;
910
}
911
if((network.ifr_flags & IFF_UP) == 0){
912
network.ifr_flags |= IFF_UP;
913
ret = ioctl(sd, SIOCSIFFLAGS, &network);
914
if(ret == -1){
915
perror("ioctl SIOCSIFFLAGS");
916
exitcode = EXIT_FAILURE;
917
goto end;
918
}
919
}
920
close(sd);
921
}
922
923
uid = getuid();
924
gid = getgid();
925
926
ret = setuid(uid);
927
if (ret == -1){
928
perror("setuid");
929
}
930
931
setgid(gid);
932
if (ret == -1){
933
perror("setgid");
934
}
935
936
if_index = (AvahiIfIndex) if_nametoindex(interface);
937
if(if_index == 0){
938
fprintf(stderr, "No such interface: \"%s\"\n", interface);
939
exit(EXIT_FAILURE);
940
}
941
942
if(connect_to != NULL){
943
/* Connect directly, do not use Zeroconf */
944
/* (Mainly meant for debugging) */
945
char *address = strrchr(connect_to, ':');
946
if(address == NULL){
947
fprintf(stderr, "No colon in address\n");
948
exitcode = EXIT_FAILURE;
949
goto end;
950
}
951
errno = 0;
952
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
953
if(errno){
954
perror("Bad port number");
955
exitcode = EXIT_FAILURE;
956
goto end;
957
}
958
*address = '\0';
959
address = connect_to;
960
ret = start_mandos_communication(address, port, if_index, &mc);
961
if(ret < 0){
962
exitcode = EXIT_FAILURE;
963
} else {
964
exitcode = EXIT_SUCCESS;
965
}
966
goto end;
967
}
968
969
if (not debug){
970
avahi_set_log_function(empty_log);
971
}
972
973
/* Initialize the pseudo-RNG for Avahi */
974
srand((unsigned int) time(NULL));
975
976
/* Allocate main Avahi loop object */
977
mc.simple_poll = avahi_simple_poll_new();
978
if (mc.simple_poll == NULL) {
979
fprintf(stderr, "Avahi: Failed to create simple poll"
980
" object.\n");
981
exitcode = EXIT_FAILURE;
982
goto end;
983
}
984
985
{
986
AvahiServerConfig config;
987
/* Do not publish any local Zeroconf records */
988
avahi_server_config_init(&config);
989
config.publish_hinfo = 0;
990
config.publish_addresses = 0;
991
config.publish_workstation = 0;
992
config.publish_domain = 0;
993
994
/* Allocate a new server */
995
mc.server = avahi_server_new(avahi_simple_poll_get
996
(mc.simple_poll), &config, NULL,
997
NULL, &error);
998
999
/* Free the Avahi configuration data */
1000
avahi_server_config_free(&config);
1001
}
1002
1003
/* Check if creating the Avahi server object succeeded */
1004
if (mc.server == NULL) {
1005
fprintf(stderr, "Failed to create Avahi server: %s\n",
1006
avahi_strerror(error));
1007
exitcode = EXIT_FAILURE;
1008
goto end;
1009
}
1010
1011
/* Create the Avahi service browser */
1012
sb = avahi_s_service_browser_new(mc.server, if_index,
1013
AVAHI_PROTO_INET6,
1014
"_mandos._tcp", NULL, 0,
1015
browse_callback, &mc);
1016
if (sb == NULL) {
1017
fprintf(stderr, "Failed to create service browser: %s\n",
1018
avahi_strerror(avahi_server_errno(mc.server)));
1019
exitcode = EXIT_FAILURE;
1020
goto end;
1021
}
1022
1023
/* Run the main loop */
1024
1025
if (debug){
1026
fprintf(stderr, "Starting Avahi loop search\n");
1027
}
1028
1029
avahi_simple_poll_loop(mc.simple_poll);
1030
1031
end:
1032
1033
if (debug){
1034
fprintf(stderr, "%s exiting\n", argv[0]);
1035
}
1036
1037
/* Cleanup things */
1038
if (sb != NULL)
1039
avahi_s_service_browser_free(sb);
1040
1041
if (mc.server != NULL)
1042
avahi_server_free(mc.server);
1043
1044
if (mc.simple_poll != NULL)
1045
avahi_simple_poll_free(mc.simple_poll);
1046
free(pubkeyfilename);
1047
free(seckeyfilename);
1048
1049
if (gnutls_initalized){
1050
gnutls_certificate_free_credentials(mc.cred);
1051
gnutls_global_deinit ();
1052
}
1053
1054
return exitcode;
1055
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0