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- Committer: Teddy Hogeborn
- Date: 2008-09-06 17:24:58 UTC
- Revision ID: teddy@fukt.bsnet.se-20080906172458-2x5wlfkn7oqckt1y
* legalnotice.xml: Copy DocBook 4.4-formatted text from
<http://www.gnu.org/licenses/gpl-3.0.dbk>.
<http://www.gnu.org/licenses/gpl-3.0.dbk>.
- files added:
- .bzrignore
- plugins.d
- files removed:
- bad-ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- files modified:
- Makefile
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 © 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, 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
/*
105
#define PATHDIR "/conf/conf.d/mandos"
106
*/
107
108
#define PATHDIR "/conf/conf.d/mandos"
109
#define SECKEY "seckey.txt"
110
#define PUBKEY "pubkey.txt"
111
112
bool debug = false;
113
static const char mandos_protocol_version[] = "1";
114
const char *argp_program_version = "mandos-client 1.0";
115
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
116
117
/* Used for passing in values through the Avahi callback functions */
118
typedef struct {
119
AvahiSimplePoll *simple_poll;
120
AvahiServer *server;
121
gnutls_certificate_credentials_t cred;
122
unsigned int dh_bits;
123
gnutls_dh_params_t dh_params;
124
const char *priority;
125
gpgme_ctx_t ctx;
126
} mandos_context;
127
128
/*
129
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
130
* "buffer_capacity" is how much is currently allocated,
131
* "buffer_length" is how much is already used.
132
*/
133
size_t adjustbuffer(char **buffer, size_t buffer_length,
134
size_t buffer_capacity){
135
if (buffer_length + BUFFER_SIZE > buffer_capacity){
136
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
137
if (buffer == NULL){
138
return 0;
139
}
140
buffer_capacity += BUFFER_SIZE;
141
}
142
return buffer_capacity;
143
}
144
145
/*
146
* Initialize GPGME.
147
*/
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
149
const char *pubkey, const char *tempdir){
150
int ret;
151
gpgme_error_t rc;
152
gpgme_engine_info_t engine_info;
153
154
155
/*
156
* Helper function to insert pub and seckey to the enigne keyring.
157
*/
158
bool import_key(const char *filename){
159
int fd;
160
gpgme_data_t pgp_data;
161
162
fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
163
if(fd == -1){
164
perror("open");
165
return false;
166
}
167
168
rc = gpgme_data_new_from_fd(&pgp_data, fd);
169
if (rc != GPG_ERR_NO_ERROR){
170
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
171
gpgme_strsource(rc), gpgme_strerror(rc));
172
return false;
173
}
174
175
rc = gpgme_op_import(mc->ctx, pgp_data);
176
if (rc != GPG_ERR_NO_ERROR){
177
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
178
gpgme_strsource(rc), gpgme_strerror(rc));
179
return false;
180
}
181
182
ret = TEMP_FAILURE_RETRY(close(fd));
183
if(ret == -1){
184
perror("close");
185
}
186
gpgme_data_release(pgp_data);
187
return true;
188
}
189
190
if (debug){
191
fprintf(stderr, "Initialize gpgme\n");
192
}
193
194
/* Init GPGME */
195
gpgme_check_version(NULL);
196
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
197
if (rc != GPG_ERR_NO_ERROR){
198
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
199
gpgme_strsource(rc), gpgme_strerror(rc));
200
return false;
201
}
202
203
/* Set GPGME home directory for the OpenPGP engine only */
204
rc = gpgme_get_engine_info (&engine_info);
205
if (rc != GPG_ERR_NO_ERROR){
206
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
207
gpgme_strsource(rc), gpgme_strerror(rc));
208
return false;
209
}
210
while(engine_info != NULL){
211
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
212
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
213
engine_info->file_name, tempdir);
214
break;
215
}
216
engine_info = engine_info->next;
217
}
218
if(engine_info == NULL){
219
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
220
return false;
221
}
222
223
/* Create new GPGME "context" */
224
rc = gpgme_new(&(mc->ctx));
225
if (rc != GPG_ERR_NO_ERROR){
226
fprintf(stderr, "bad gpgme_new: %s: %s\n",
227
gpgme_strsource(rc), gpgme_strerror(rc));
228
return false;
229
}
230
231
if (not import_key(pubkey) or not import_key(seckey)){
232
return false;
233
}
234
235
return true;
236
}
237
238
/*
239
* Decrypt OpenPGP data.
240
* Returns -1 on error
241
*/
242
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
243
const char *cryptotext,
244
size_t crypto_size,
245
char **plaintext){
246
gpgme_data_t dh_crypto, dh_plain;
247
gpgme_error_t rc;
248
ssize_t ret;
249
size_t plaintext_capacity = 0;
250
ssize_t plaintext_length = 0;
251
252
if (debug){
253
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
254
}
255
256
/* Create new GPGME data buffer from memory cryptotext */
257
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
258
0);
259
if (rc != GPG_ERR_NO_ERROR){
260
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
261
gpgme_strsource(rc), gpgme_strerror(rc));
262
return -1;
263
}
264
265
/* Create new empty GPGME data buffer for the plaintext */
266
rc = gpgme_data_new(&dh_plain);
267
if (rc != GPG_ERR_NO_ERROR){
268
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
269
gpgme_strsource(rc), gpgme_strerror(rc));
270
gpgme_data_release(dh_crypto);
271
return -1;
272
}
273
274
/* Decrypt data from the cryptotext data buffer to the plaintext
275
data buffer */
276
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
277
if (rc != GPG_ERR_NO_ERROR){
278
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
280
plaintext_length = -1;
281
if (debug){
282
gpgme_decrypt_result_t result;
283
result = gpgme_op_decrypt_result(mc->ctx);
284
if (result == NULL){
285
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
286
} else {
287
fprintf(stderr, "Unsupported algorithm: %s\n",
288
result->unsupported_algorithm);
289
fprintf(stderr, "Wrong key usage: %u\n",
290
result->wrong_key_usage);
291
if(result->file_name != NULL){
292
fprintf(stderr, "File name: %s\n", result->file_name);
293
}
294
gpgme_recipient_t recipient;
295
recipient = result->recipients;
296
if(recipient){
297
while(recipient != NULL){
298
fprintf(stderr, "Public key algorithm: %s\n",
299
gpgme_pubkey_algo_name(recipient->pubkey_algo));
300
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
301
fprintf(stderr, "Secret key available: %s\n",
302
recipient->status == GPG_ERR_NO_SECKEY
303
? "No" : "Yes");
304
recipient = recipient->next;
305
}
306
}
307
}
308
}
309
goto decrypt_end;
310
}
311
312
if(debug){
313
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
314
}
315
316
/* Seek back to the beginning of the GPGME plaintext data buffer */
317
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
318
perror("pgpme_data_seek");
319
plaintext_length = -1;
320
goto decrypt_end;
321
}
322
323
*plaintext = NULL;
324
while(true){
325
plaintext_capacity = adjustbuffer(plaintext,
326
(size_t)plaintext_length,
327
plaintext_capacity);
328
if (plaintext_capacity == 0){
329
perror("adjustbuffer");
330
plaintext_length = -1;
331
goto decrypt_end;
332
}
333
334
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
335
BUFFER_SIZE);
336
/* Print the data, if any */
337
if (ret == 0){
338
/* EOF */
339
break;
340
}
341
if(ret < 0){
342
perror("gpgme_data_read");
343
plaintext_length = -1;
344
goto decrypt_end;
345
}
346
plaintext_length += ret;
347
}
348
349
if(debug){
350
fprintf(stderr, "Decrypted password is: ");
351
for(ssize_t i = 0; i < plaintext_length; i++){
352
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
353
}
354
fprintf(stderr, "\n");
355
}
356
357
decrypt_end:
358
359
/* Delete the GPGME cryptotext data buffer */
360
gpgme_data_release(dh_crypto);
361
362
/* Delete the GPGME plaintext data buffer */
363
gpgme_data_release(dh_plain);
364
return plaintext_length;
365
}
366
367
static const char * safer_gnutls_strerror (int value) {
368
const char *ret = gnutls_strerror (value); /* Spurious warning */
369
if (ret == NULL)
370
ret = "(unknown)";
371
return ret;
372
}
373
374
/* GnuTLS log function callback */
375
static void debuggnutls(__attribute__((unused)) int level,
376
const char* string){
377
fprintf(stderr, "GnuTLS: %s", string);
378
}
379
380
static int init_gnutls_global(mandos_context *mc,
381
const char *pubkeyfilename,
382
const char *seckeyfilename){
383
int ret;
384
385
if(debug){
386
fprintf(stderr, "Initializing GnuTLS\n");
387
}
388
389
ret = gnutls_global_init();
390
if (ret != GNUTLS_E_SUCCESS) {
391
fprintf (stderr, "GnuTLS global_init: %s\n",
392
safer_gnutls_strerror(ret));
393
return -1;
394
}
395
396
if (debug){
397
/* "Use a log level over 10 to enable all debugging options."
398
* - GnuTLS manual
399
*/
400
gnutls_global_set_log_level(11);
401
gnutls_global_set_log_function(debuggnutls);
402
}
403
404
/* OpenPGP credentials */
405
gnutls_certificate_allocate_credentials(&mc->cred);
406
if (ret != GNUTLS_E_SUCCESS){
407
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
408
warning */
409
safer_gnutls_strerror(ret));
410
gnutls_global_deinit ();
411
return -1;
412
}
413
414
if(debug){
415
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
416
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
417
seckeyfilename);
418
}
419
420
ret = gnutls_certificate_set_openpgp_key_file
421
(mc->cred, pubkeyfilename, seckeyfilename,
422
GNUTLS_OPENPGP_FMT_BASE64);
423
if (ret != GNUTLS_E_SUCCESS) {
424
fprintf(stderr,
425
"Error[%d] while reading the OpenPGP key pair ('%s',"
426
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
427
fprintf(stderr, "The GnuTLS error is: %s\n",
428
safer_gnutls_strerror(ret));
429
goto globalfail;
430
}
431
432
/* GnuTLS server initialization */
433
ret = gnutls_dh_params_init(&mc->dh_params);
434
if (ret != GNUTLS_E_SUCCESS) {
435
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
436
" %s\n", safer_gnutls_strerror(ret));
437
goto globalfail;
438
}
439
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
440
if (ret != GNUTLS_E_SUCCESS) {
441
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
442
safer_gnutls_strerror(ret));
443
goto globalfail;
444
}
445
446
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
447
448
return 0;
449
450
globalfail:
451
452
gnutls_certificate_free_credentials(mc->cred);
453
gnutls_global_deinit();
454
return -1;
455
}
456
457
static int init_gnutls_session(mandos_context *mc,
458
gnutls_session_t *session){
459
int ret;
460
/* GnuTLS session creation */
461
ret = gnutls_init(session, GNUTLS_SERVER);
462
if (ret != GNUTLS_E_SUCCESS){
463
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
464
safer_gnutls_strerror(ret));
465
}
466
467
{
468
const char *err;
469
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
470
if (ret != GNUTLS_E_SUCCESS) {
471
fprintf(stderr, "Syntax error at: %s\n", err);
472
fprintf(stderr, "GnuTLS error: %s\n",
473
safer_gnutls_strerror(ret));
474
gnutls_deinit (*session);
475
return -1;
476
}
477
}
478
479
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
480
mc->cred);
481
if (ret != GNUTLS_E_SUCCESS) {
482
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
483
safer_gnutls_strerror(ret));
484
gnutls_deinit (*session);
485
return -1;
486
}
487
488
/* ignore client certificate if any. */
489
gnutls_certificate_server_set_request (*session,
490
GNUTLS_CERT_IGNORE);
491
492
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
493
494
return 0;
495
}
496
497
/* Avahi log function callback */
498
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
499
__attribute__((unused)) const char *txt){}
500
501
/* Called when a Mandos server is found */
502
static int start_mandos_communication(const char *ip, uint16_t port,
503
AvahiIfIndex if_index,
504
mandos_context *mc){
505
int ret, tcp_sd;
506
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
507
char *buffer = NULL;
508
char *decrypted_buffer;
509
size_t buffer_length = 0;
510
size_t buffer_capacity = 0;
511
ssize_t decrypted_buffer_size;
512
size_t written;
513
int retval = 0;
514
char interface[IF_NAMESIZE];
515
gnutls_session_t session;
516
517
ret = init_gnutls_session (mc, &session);
518
if (ret != 0){
519
return -1;
520
}
521
522
if(debug){
523
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
524
"\n", ip, port);
525
}
526
527
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
528
if(tcp_sd < 0) {
529
perror("socket");
530
return -1;
531
}
532
533
if(debug){
534
if(if_indextoname((unsigned int)if_index, interface) == NULL){
535
perror("if_indextoname");
536
return -1;
537
}
538
fprintf(stderr, "Binding to interface %s\n", interface);
539
}
540
541
memset(&to, 0, sizeof(to));
542
to.in6.sin6_family = AF_INET6;
543
/* It would be nice to have a way to detect if we were passed an
544
IPv4 address here. Now we assume an IPv6 address. */
545
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
546
if (ret < 0 ){
547
perror("inet_pton");
548
return -1;
549
}
550
if(ret == 0){
551
fprintf(stderr, "Bad address: %s\n", ip);
552
return -1;
553
}
554
to.in6.sin6_port = htons(port); /* Spurious warning */
555
556
to.in6.sin6_scope_id = (uint32_t)if_index;
557
558
if(debug){
559
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
560
port);
561
char addrstr[INET6_ADDRSTRLEN] = "";
562
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
563
sizeof(addrstr)) == NULL){
564
perror("inet_ntop");
565
} else {
566
if(strcmp(addrstr, ip) != 0){
567
fprintf(stderr, "Canonical address form: %s\n", addrstr);
568
}
569
}
570
}
571
572
ret = connect(tcp_sd, &to.in, sizeof(to));
573
if (ret < 0){
574
perror("connect");
575
return -1;
576
}
577
578
const char *out = mandos_protocol_version;
579
written = 0;
580
while (true){
581
size_t out_size = strlen(out);
582
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
583
out_size - written));
584
if (ret == -1){
585
perror("write");
586
retval = -1;
587
goto mandos_end;
588
}
589
written += (size_t)ret;
590
if(written < out_size){
591
continue;
592
} else {
593
if (out == mandos_protocol_version){
594
written = 0;
595
out = "\r\n";
596
} else {
597
break;
598
}
599
}
600
}
601
602
if(debug){
603
fprintf(stderr, "Establishing TLS session with %s\n", ip);
604
}
605
606
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
607
608
do{
609
ret = gnutls_handshake (session);
610
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
611
612
if (ret != GNUTLS_E_SUCCESS){
613
if(debug){
614
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
615
gnutls_perror (ret);
616
}
617
retval = -1;
618
goto mandos_end;
619
}
620
621
/* Read OpenPGP packet that contains the wanted password */
622
623
if(debug){
624
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
625
ip);
626
}
627
628
while(true){
629
buffer_capacity = adjustbuffer(&buffer, buffer_length,
630
buffer_capacity);
631
if (buffer_capacity == 0){
632
perror("adjustbuffer");
633
retval = -1;
634
goto mandos_end;
635
}
636
637
ret = gnutls_record_recv(session, buffer+buffer_length,
638
BUFFER_SIZE);
639
if (ret == 0){
640
break;
641
}
642
if (ret < 0){
643
switch(ret){
644
case GNUTLS_E_INTERRUPTED:
645
case GNUTLS_E_AGAIN:
646
break;
647
case GNUTLS_E_REHANDSHAKE:
648
do{
649
ret = gnutls_handshake (session);
650
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
651
if (ret < 0){
652
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
653
gnutls_perror (ret);
654
retval = -1;
655
goto mandos_end;
656
}
657
break;
658
default:
659
fprintf(stderr, "Unknown error while reading data from"
660
" encrypted session with Mandos server\n");
661
retval = -1;
662
gnutls_bye (session, GNUTLS_SHUT_RDWR);
663
goto mandos_end;
664
}
665
} else {
666
buffer_length += (size_t) ret;
667
}
668
}
669
670
if(debug){
671
fprintf(stderr, "Closing TLS session\n");
672
}
673
674
gnutls_bye (session, GNUTLS_SHUT_RDWR);
675
676
if (buffer_length > 0){
677
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
678
buffer_length,
679
&decrypted_buffer);
680
if (decrypted_buffer_size >= 0){
681
written = 0;
682
while(written < (size_t) decrypted_buffer_size){
683
ret = (int)fwrite (decrypted_buffer + written, 1,
684
(size_t)decrypted_buffer_size - written,
685
stdout);
686
if(ret == 0 and ferror(stdout)){
687
if(debug){
688
fprintf(stderr, "Error writing encrypted data: %s\n",
689
strerror(errno));
690
}
691
retval = -1;
692
break;
693
}
694
written += (size_t)ret;
695
}
696
free(decrypted_buffer);
697
} else {
698
retval = -1;
699
}
700
} else {
701
retval = -1;
702
}
703
704
/* Shutdown procedure */
705
706
mandos_end:
707
free(buffer);
708
ret = TEMP_FAILURE_RETRY(close(tcp_sd));
709
if(ret == -1){
710
perror("close");
711
}
712
gnutls_deinit (session);
713
return retval;
714
}
715
716
static void resolve_callback(AvahiSServiceResolver *r,
717
AvahiIfIndex interface,
718
AVAHI_GCC_UNUSED AvahiProtocol protocol,
719
AvahiResolverEvent event,
720
const char *name,
721
const char *type,
722
const char *domain,
723
const char *host_name,
724
const AvahiAddress *address,
725
uint16_t port,
726
AVAHI_GCC_UNUSED AvahiStringList *txt,
727
AVAHI_GCC_UNUSED AvahiLookupResultFlags
728
flags,
729
void* userdata) {
730
mandos_context *mc = userdata;
731
assert(r);
732
733
/* Called whenever a service has been resolved successfully or
734
timed out */
735
736
switch (event) {
737
default:
738
case AVAHI_RESOLVER_FAILURE:
739
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
740
" of type '%s' in domain '%s': %s\n", name, type, domain,
741
avahi_strerror(avahi_server_errno(mc->server)));
742
break;
743
744
case AVAHI_RESOLVER_FOUND:
745
{
746
char ip[AVAHI_ADDRESS_STR_MAX];
747
avahi_address_snprint(ip, sizeof(ip), address);
748
if(debug){
749
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
750
PRIu16 ") on port %d\n", name, host_name, ip,
751
interface, port);
752
}
753
int ret = start_mandos_communication(ip, port, interface, mc);
754
if (ret == 0){
755
avahi_simple_poll_quit(mc->simple_poll);
756
}
757
}
758
}
759
avahi_s_service_resolver_free(r);
760
}
761
762
static void browse_callback( AvahiSServiceBrowser *b,
763
AvahiIfIndex interface,
764
AvahiProtocol protocol,
765
AvahiBrowserEvent event,
766
const char *name,
767
const char *type,
768
const char *domain,
769
AVAHI_GCC_UNUSED AvahiLookupResultFlags
770
flags,
771
void* userdata) {
772
mandos_context *mc = userdata;
773
assert(b);
774
775
/* Called whenever a new services becomes available on the LAN or
776
is removed from the LAN */
777
778
switch (event) {
779
default:
780
case AVAHI_BROWSER_FAILURE:
781
782
fprintf(stderr, "(Avahi browser) %s\n",
783
avahi_strerror(avahi_server_errno(mc->server)));
784
avahi_simple_poll_quit(mc->simple_poll);
785
return;
786
787
case AVAHI_BROWSER_NEW:
788
/* We ignore the returned Avahi resolver object. In the callback
789
function we free it. If the Avahi server is terminated before
790
the callback function is called the Avahi server will free the
791
resolver for us. */
792
793
if (!(avahi_s_service_resolver_new(mc->server, interface,
794
protocol, name, type, domain,
795
AVAHI_PROTO_INET6, 0,
796
resolve_callback, mc)))
797
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
798
name, avahi_strerror(avahi_server_errno(mc->server)));
799
break;
800
801
case AVAHI_BROWSER_REMOVE:
802
break;
803
804
case AVAHI_BROWSER_ALL_FOR_NOW:
805
case AVAHI_BROWSER_CACHE_EXHAUSTED:
806
if(debug){
807
fprintf(stderr, "No Mandos server found, still searching...\n");
808
}
809
break;
810
}
811
}
812
813
int main(int argc, char *argv[]){
814
AvahiSServiceBrowser *sb = NULL;
815
int error;
816
int ret;
817
int exitcode = EXIT_SUCCESS;
818
const char *interface = "eth0";
819
struct ifreq network;
820
int sd;
821
uid_t uid;
822
gid_t gid;
823
char *connect_to = NULL;
824
char tempdir[] = "/tmp/mandosXXXXXX";
825
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
826
const char *seckey = PATHDIR "/" SECKEY;
827
const char *pubkey = PATHDIR "/" PUBKEY;
828
829
mandos_context mc = { .simple_poll = NULL, .server = NULL,
830
.dh_bits = 1024, .priority = "SECURE256"
831
":!CTYPE-X.509:+CTYPE-OPENPGP" };
832
bool gnutls_initalized = false;
833
bool pgpme_initalized = false;
834
835
{
836
struct argp_option options[] = {
837
{ .name = "debug", .key = 128,
838
.doc = "Debug mode", .group = 3 },
839
{ .name = "connect", .key = 'c',
840
.arg = "ADDRESS:PORT",
841
.doc = "Connect directly to a specific Mandos server",
842
.group = 1 },
843
{ .name = "interface", .key = 'i',
844
.arg = "NAME",
845
.doc = "Interface that will be used to search for Mandos"
846
" servers",
847
.group = 1 },
848
{ .name = "seckey", .key = 's',
849
.arg = "FILE",
850
.doc = "OpenPGP secret key file base name",
851
.group = 1 },
852
{ .name = "pubkey", .key = 'p',
853
.arg = "FILE",
854
.doc = "OpenPGP public key file base name",
855
.group = 2 },
856
{ .name = "dh-bits", .key = 129,
857
.arg = "BITS",
858
.doc = "Bit length of the prime number used in the"
859
" Diffie-Hellman key exchange",
860
.group = 2 },
861
{ .name = "priority", .key = 130,
862
.arg = "STRING",
863
.doc = "GnuTLS priority string for the TLS handshake",
864
.group = 1 },
865
{ .name = NULL }
866
};
867
868
error_t parse_opt (int key, char *arg,
869
struct argp_state *state) {
870
/* Get the INPUT argument from `argp_parse', which we know is
871
a pointer to our plugin list pointer. */
872
switch (key) {
873
case 128: /* --debug */
874
debug = true;
875
break;
876
case 'c': /* --connect */
877
connect_to = arg;
878
break;
879
case 'i': /* --interface */
880
interface = arg;
881
break;
882
case 's': /* --seckey */
883
seckey = arg;
884
break;
885
case 'p': /* --pubkey */
886
pubkey = arg;
887
break;
888
case 129: /* --dh-bits */
889
errno = 0;
890
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
891
if (errno){
892
perror("strtol");
893
exit(EXIT_FAILURE);
894
}
895
break;
896
case 130: /* --priority */
897
mc.priority = arg;
898
break;
899
case ARGP_KEY_ARG:
900
argp_usage (state);
901
case ARGP_KEY_END:
902
break;
903
default:
904
return ARGP_ERR_UNKNOWN;
905
}
906
return 0;
907
}
908
909
struct argp argp = { .options = options, .parser = parse_opt,
910
.args_doc = "",
911
.doc = "Mandos client -- Get and decrypt"
912
" passwords from a Mandos server" };
913
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
914
if (ret == ARGP_ERR_UNKNOWN){
915
fprintf(stderr, "Unknown error while parsing arguments\n");
916
exitcode = EXIT_FAILURE;
917
goto end;
918
}
919
}
920
921
/* If the interface is down, bring it up */
922
{
923
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
924
if(sd < 0) {
925
perror("socket");
926
exitcode = EXIT_FAILURE;
927
goto end;
928
}
929
strcpy(network.ifr_name, interface);
930
ret = ioctl(sd, SIOCGIFFLAGS, &network);
931
if(ret == -1){
932
perror("ioctl SIOCGIFFLAGS");
933
exitcode = EXIT_FAILURE;
934
goto end;
935
}
936
if((network.ifr_flags & IFF_UP) == 0){
937
network.ifr_flags |= IFF_UP;
938
ret = ioctl(sd, SIOCSIFFLAGS, &network);
939
if(ret == -1){
940
perror("ioctl SIOCSIFFLAGS");
941
exitcode = EXIT_FAILURE;
942
goto end;
943
}
944
}
945
ret = TEMP_FAILURE_RETRY(close(sd));
946
if(ret == -1){
947
perror("close");
948
}
949
}
950
951
uid = getuid();
952
gid = getgid();
953
954
ret = setuid(uid);
955
if (ret == -1){
956
perror("setuid");
957
}
958
959
setgid(gid);
960
if (ret == -1){
961
perror("setgid");
962
}
963
964
ret = init_gnutls_global(&mc, pubkey, seckey);
965
if (ret == -1){
966
fprintf(stderr, "init_gnutls_global failed\n");
967
exitcode = EXIT_FAILURE;
968
goto end;
969
} else {
970
gnutls_initalized = true;
971
}
972
973
if(mkdtemp(tempdir) == NULL){
974
perror("mkdtemp");
975
tempdir[0] = '\0';
976
goto end;
977
}
978
979
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
980
fprintf(stderr, "pgpme_initalized failed\n");
981
exitcode = EXIT_FAILURE;
982
goto end;
983
} else {
984
pgpme_initalized = true;
985
}
986
987
if_index = (AvahiIfIndex) if_nametoindex(interface);
988
if(if_index == 0){
989
fprintf(stderr, "No such interface: \"%s\"\n", interface);
990
exit(EXIT_FAILURE);
991
}
992
993
if(connect_to != NULL){
994
/* Connect directly, do not use Zeroconf */
995
/* (Mainly meant for debugging) */
996
char *address = strrchr(connect_to, ':');
997
if(address == NULL){
998
fprintf(stderr, "No colon in address\n");
999
exitcode = EXIT_FAILURE;
1000
goto end;
1001
}
1002
errno = 0;
1003
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1004
if(errno){
1005
perror("Bad port number");
1006
exitcode = EXIT_FAILURE;
1007
goto end;
1008
}
1009
*address = '\0';
1010
address = connect_to;
1011
ret = start_mandos_communication(address, port, if_index, &mc);
1012
if(ret < 0){
1013
exitcode = EXIT_FAILURE;
1014
} else {
1015
exitcode = EXIT_SUCCESS;
1016
}
1017
goto end;
1018
}
1019
1020
if (not debug){
1021
avahi_set_log_function(empty_log);
1022
}
1023
1024
/* Initialize the pseudo-RNG for Avahi */
1025
srand((unsigned int) time(NULL));
1026
1027
/* Allocate main Avahi loop object */
1028
mc.simple_poll = avahi_simple_poll_new();
1029
if (mc.simple_poll == NULL) {
1030
fprintf(stderr, "Avahi: Failed to create simple poll"
1031
" object.\n");
1032
exitcode = EXIT_FAILURE;
1033
goto end;
1034
}
1035
1036
{
1037
AvahiServerConfig config;
1038
/* Do not publish any local Zeroconf records */
1039
avahi_server_config_init(&config);
1040
config.publish_hinfo = 0;
1041
config.publish_addresses = 0;
1042
config.publish_workstation = 0;
1043
config.publish_domain = 0;
1044
1045
/* Allocate a new server */
1046
mc.server = avahi_server_new(avahi_simple_poll_get
1047
(mc.simple_poll), &config, NULL,
1048
NULL, &error);
1049
1050
/* Free the Avahi configuration data */
1051
avahi_server_config_free(&config);
1052
}
1053
1054
/* Check if creating the Avahi server object succeeded */
1055
if (mc.server == NULL) {
1056
fprintf(stderr, "Failed to create Avahi server: %s\n",
1057
avahi_strerror(error));
1058
exitcode = EXIT_FAILURE;
1059
goto end;
1060
}
1061
1062
/* Create the Avahi service browser */
1063
sb = avahi_s_service_browser_new(mc.server, if_index,
1064
AVAHI_PROTO_INET6,
1065
"_mandos._tcp", NULL, 0,
1066
browse_callback, &mc);
1067
if (sb == NULL) {
1068
fprintf(stderr, "Failed to create service browser: %s\n",
1069
avahi_strerror(avahi_server_errno(mc.server)));
1070
exitcode = EXIT_FAILURE;
1071
goto end;
1072
}
1073
1074
/* Run the main loop */
1075
1076
if (debug){
1077
fprintf(stderr, "Starting Avahi loop search\n");
1078
}
1079
1080
avahi_simple_poll_loop(mc.simple_poll);
1081
1082
end:
1083
1084
if (debug){
1085
fprintf(stderr, "%s exiting\n", argv[0]);
1086
}
1087
1088
/* Cleanup things */
1089
if (sb != NULL)
1090
avahi_s_service_browser_free(sb);
1091
1092
if (mc.server != NULL)
1093
avahi_server_free(mc.server);
1094
1095
if (mc.simple_poll != NULL)
1096
avahi_simple_poll_free(mc.simple_poll);
1097
1098
if (gnutls_initalized){
1099
gnutls_certificate_free_credentials(mc.cred);
1100
gnutls_global_deinit ();
1101
}
1102
1103
if(pgpme_initalized){
1104
gpgme_release(mc.ctx);
1105
}
1106
1107
/* Removes the temp directory used by GPGME */
1108
if(tempdir[0] != '\0'){
1109
DIR *d;
1110
struct dirent *direntry;
1111
d = opendir(tempdir);
1112
if(d == NULL){
1113
perror("opendir");
1114
} else {
1115
while(true){
1116
direntry = readdir(d);
1117
if(direntry == NULL){
1118
break;
1119
}
1120
if (direntry->d_type == DT_REG){
1121
char *fullname = NULL;
1122
ret = asprintf(&fullname, "%s/%s", tempdir,
1123
direntry->d_name);
1124
if(ret < 0){
1125
perror("asprintf");
1126
continue;
1127
}
1128
ret = unlink(fullname);
1129
if(ret == -1){
1130
fprintf(stderr, "unlink(\"%s\"): %s",
1131
fullname, strerror(errno));
1132
}
1133
free(fullname);
1134
}
1135
}
1136
}
1137
ret = rmdir(tempdir);
1138
if(ret == -1){
1139
perror("rmdir");
1140
}
1141
}
1142
1143
return exitcode;
1144
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0