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- Committer: Teddy Hogeborn
- Date: 2009-01-27 15:42:41 UTC
- Revision ID: teddy@fukt.bsnet.se-20090127154241-x0kosjtvuo0iuptd
* plugins.d/mandos-client.c (main): Use separate bool variable instead
of clumsy NUL character in
"tempdir". Bug fix: Don't try to
remove temp directory if it was
never created.
of clumsy NUL character in
"tempdir". Bug fix: Don't try to
remove temp directory if it was
never created.
- files added:
- .bzr-builddeb
- debian
- debian/po
- 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 © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
14
*
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
19
*
20
* This program is distributed in the hope that it will be useful, but
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
* General Public License for more details.
24
*
25
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
*
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
*/
31
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#define _LARGEFILE_SOURCE
34
#define _FILE_OFFSET_BITS 64
35
36
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
37
38
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
40
remove() */
41
#include <stdint.h> /* uint16_t, uint32_t */
42
#include <stddef.h> /* NULL, size_t, ssize_t */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
44
srand() */
45
#include <stdbool.h> /* bool, true */
46
#include <string.h> /* memset(), strcmp(), strlen(),
47
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
49
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
53
DIR */
54
#include <sys/stat.h> /* open() */
55
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
57
connect() */
58
#include <fcntl.h> /* open() */
59
#include <dirent.h> /* opendir(), struct dirent, readdir()
60
*/
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* time() */
65
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
SIOCSIFFLAGS, if_indextoname(),
67
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
69
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
getuid(), getgid(), setuid(),
71
setgid() */
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
74
#include <argp.h> /* struct argp_option, error_t, struct
75
argp_state, struct argp,
76
argp_parse(), ARGP_KEY_ARG,
77
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
78
79
/* Avahi */
80
/* All Avahi types, constants and functions
81
Avahi*, avahi_*,
82
AVAHI_* */
83
#include <avahi-core/core.h>
84
#include <avahi-core/lookup.h>
85
#include <avahi-core/log.h>
86
#include <avahi-common/simple-watch.h>
87
#include <avahi-common/malloc.h>
88
#include <avahi-common/error.h>
89
90
/* GnuTLS */
91
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
92
functions:
93
gnutls_*
94
init_gnutls_session(),
95
GNUTLS_* */
96
#include <gnutls/openpgp.h>
97
/* gnutls_certificate_set_openpgp_key_file(),
98
GNUTLS_OPENPGP_FMT_BASE64 */
99
100
/* GPGME */
101
#include <gpgme.h> /* All GPGME types, constants and
102
functions:
103
gpgme_*
104
GPGME_PROTOCOL_OpenPGP,
105
GPG_ERR_NO_* */
106
107
#define BUFFER_SIZE 256
108
109
#define PATHDIR "/conf/conf.d/mandos"
110
#define SECKEY "seckey.txt"
111
#define PUBKEY "pubkey.txt"
112
113
bool debug = false;
114
static const char mandos_protocol_version[] = "1";
115
const char *argp_program_version = "mandos-client " VERSION;
116
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
117
118
/* Used for passing in values through the Avahi callback functions */
119
typedef struct {
120
AvahiSimplePoll *simple_poll;
121
AvahiServer *server;
122
gnutls_certificate_credentials_t cred;
123
unsigned int dh_bits;
124
gnutls_dh_params_t dh_params;
125
const char *priority;
126
gpgme_ctx_t ctx;
127
} mandos_context;
128
129
/*
130
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
131
* "buffer_capacity" is how much is currently allocated,
132
* "buffer_length" is how much is already used.
133
*/
134
size_t adjustbuffer(char **buffer, size_t buffer_length,
135
size_t buffer_capacity){
136
if(buffer_length + BUFFER_SIZE > buffer_capacity){
137
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
138
if(buffer == NULL){
139
return 0;
140
}
141
buffer_capacity += BUFFER_SIZE;
142
}
143
return buffer_capacity;
144
}
145
146
/*
147
* Initialize GPGME.
148
*/
149
static bool init_gpgme(mandos_context *mc, const char *seckey,
150
const char *pubkey, const char *tempdir){
151
int ret;
152
gpgme_error_t rc;
153
gpgme_engine_info_t engine_info;
154
155
156
/*
157
* Helper function to insert pub and seckey to the engine keyring.
158
*/
159
bool import_key(const char *filename){
160
int fd;
161
gpgme_data_t pgp_data;
162
163
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
164
if(fd == -1){
165
perror("open");
166
return false;
167
}
168
169
rc = gpgme_data_new_from_fd(&pgp_data, fd);
170
if(rc != GPG_ERR_NO_ERROR){
171
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
172
gpgme_strsource(rc), gpgme_strerror(rc));
173
return false;
174
}
175
176
rc = gpgme_op_import(mc->ctx, pgp_data);
177
if(rc != GPG_ERR_NO_ERROR){
178
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
179
gpgme_strsource(rc), gpgme_strerror(rc));
180
return false;
181
}
182
183
ret = (int)TEMP_FAILURE_RETRY(close(fd));
184
if(ret == -1){
185
perror("close");
186
}
187
gpgme_data_release(pgp_data);
188
return true;
189
}
190
191
if(debug){
192
fprintf(stderr, "Initialize gpgme\n");
193
}
194
195
/* Init GPGME */
196
gpgme_check_version(NULL);
197
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
198
if(rc != GPG_ERR_NO_ERROR){
199
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
200
gpgme_strsource(rc), gpgme_strerror(rc));
201
return false;
202
}
203
204
/* Set GPGME home directory for the OpenPGP engine only */
205
rc = gpgme_get_engine_info(&engine_info);
206
if(rc != GPG_ERR_NO_ERROR){
207
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
208
gpgme_strsource(rc), gpgme_strerror(rc));
209
return false;
210
}
211
while(engine_info != NULL){
212
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
213
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
214
engine_info->file_name, tempdir);
215
break;
216
}
217
engine_info = engine_info->next;
218
}
219
if(engine_info == NULL){
220
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
221
return false;
222
}
223
224
/* Create new GPGME "context" */
225
rc = gpgme_new(&(mc->ctx));
226
if(rc != GPG_ERR_NO_ERROR){
227
fprintf(stderr, "bad gpgme_new: %s: %s\n",
228
gpgme_strsource(rc), gpgme_strerror(rc));
229
return false;
230
}
231
232
if(not import_key(pubkey) or not import_key(seckey)){
233
return false;
234
}
235
236
return true;
237
}
238
239
/*
240
* Decrypt OpenPGP data.
241
* Returns -1 on error
242
*/
243
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
244
const char *cryptotext,
245
size_t crypto_size,
246
char **plaintext){
247
gpgme_data_t dh_crypto, dh_plain;
248
gpgme_error_t rc;
249
ssize_t ret;
250
size_t plaintext_capacity = 0;
251
ssize_t plaintext_length = 0;
252
253
if(debug){
254
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
255
}
256
257
/* Create new GPGME data buffer from memory cryptotext */
258
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
259
0);
260
if(rc != GPG_ERR_NO_ERROR){
261
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
262
gpgme_strsource(rc), gpgme_strerror(rc));
263
return -1;
264
}
265
266
/* Create new empty GPGME data buffer for the plaintext */
267
rc = gpgme_data_new(&dh_plain);
268
if(rc != GPG_ERR_NO_ERROR){
269
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
270
gpgme_strsource(rc), gpgme_strerror(rc));
271
gpgme_data_release(dh_crypto);
272
return -1;
273
}
274
275
/* Decrypt data from the cryptotext data buffer to the plaintext
276
data buffer */
277
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
278
if(rc != GPG_ERR_NO_ERROR){
279
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
280
gpgme_strsource(rc), gpgme_strerror(rc));
281
plaintext_length = -1;
282
if(debug){
283
gpgme_decrypt_result_t result;
284
result = gpgme_op_decrypt_result(mc->ctx);
285
if(result == NULL){
286
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
287
} else {
288
fprintf(stderr, "Unsupported algorithm: %s\n",
289
result->unsupported_algorithm);
290
fprintf(stderr, "Wrong key usage: %u\n",
291
result->wrong_key_usage);
292
if(result->file_name != NULL){
293
fprintf(stderr, "File name: %s\n", result->file_name);
294
}
295
gpgme_recipient_t recipient;
296
recipient = result->recipients;
297
if(recipient){
298
while(recipient != NULL){
299
fprintf(stderr, "Public key algorithm: %s\n",
300
gpgme_pubkey_algo_name(recipient->pubkey_algo));
301
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
302
fprintf(stderr, "Secret key available: %s\n",
303
recipient->status == GPG_ERR_NO_SECKEY
304
? "No" : "Yes");
305
recipient = recipient->next;
306
}
307
}
308
}
309
}
310
goto decrypt_end;
311
}
312
313
if(debug){
314
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
315
}
316
317
/* Seek back to the beginning of the GPGME plaintext data buffer */
318
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
319
perror("gpgme_data_seek");
320
plaintext_length = -1;
321
goto decrypt_end;
322
}
323
324
*plaintext = NULL;
325
while(true){
326
plaintext_capacity = adjustbuffer(plaintext,
327
(size_t)plaintext_length,
328
plaintext_capacity);
329
if(plaintext_capacity == 0){
330
perror("adjustbuffer");
331
plaintext_length = -1;
332
goto decrypt_end;
333
}
334
335
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
336
BUFFER_SIZE);
337
/* Print the data, if any */
338
if(ret == 0){
339
/* EOF */
340
break;
341
}
342
if(ret < 0){
343
perror("gpgme_data_read");
344
plaintext_length = -1;
345
goto decrypt_end;
346
}
347
plaintext_length += ret;
348
}
349
350
if(debug){
351
fprintf(stderr, "Decrypted password is: ");
352
for(ssize_t i = 0; i < plaintext_length; i++){
353
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
354
}
355
fprintf(stderr, "\n");
356
}
357
358
decrypt_end:
359
360
/* Delete the GPGME cryptotext data buffer */
361
gpgme_data_release(dh_crypto);
362
363
/* Delete the GPGME plaintext data buffer */
364
gpgme_data_release(dh_plain);
365
return plaintext_length;
366
}
367
368
static const char * safer_gnutls_strerror(int value) {
369
const char *ret = gnutls_strerror(value); /* Spurious warning from
370
-Wunreachable-code */
371
if(ret == NULL)
372
ret = "(unknown)";
373
return ret;
374
}
375
376
/* GnuTLS log function callback */
377
static void debuggnutls(__attribute__((unused)) int level,
378
const char* string){
379
fprintf(stderr, "GnuTLS: %s", string);
380
}
381
382
static int init_gnutls_global(mandos_context *mc,
383
const char *pubkeyfilename,
384
const char *seckeyfilename){
385
int ret;
386
387
if(debug){
388
fprintf(stderr, "Initializing GnuTLS\n");
389
}
390
391
ret = gnutls_global_init();
392
if(ret != GNUTLS_E_SUCCESS) {
393
fprintf(stderr, "GnuTLS global_init: %s\n",
394
safer_gnutls_strerror(ret));
395
return -1;
396
}
397
398
if(debug){
399
/* "Use a log level over 10 to enable all debugging options."
400
* - GnuTLS manual
401
*/
402
gnutls_global_set_log_level(11);
403
gnutls_global_set_log_function(debuggnutls);
404
}
405
406
/* OpenPGP credentials */
407
gnutls_certificate_allocate_credentials(&mc->cred);
408
if(ret != GNUTLS_E_SUCCESS){
409
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
410
* from
411
* -Wunreachable-code
412
*/
413
safer_gnutls_strerror(ret));
414
gnutls_global_deinit();
415
return -1;
416
}
417
418
if(debug){
419
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
420
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
421
seckeyfilename);
422
}
423
424
ret = gnutls_certificate_set_openpgp_key_file
425
(mc->cred, pubkeyfilename, seckeyfilename,
426
GNUTLS_OPENPGP_FMT_BASE64);
427
if(ret != GNUTLS_E_SUCCESS) {
428
fprintf(stderr,
429
"Error[%d] while reading the OpenPGP key pair ('%s',"
430
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
431
fprintf(stderr, "The GnuTLS error is: %s\n",
432
safer_gnutls_strerror(ret));
433
goto globalfail;
434
}
435
436
/* GnuTLS server initialization */
437
ret = gnutls_dh_params_init(&mc->dh_params);
438
if(ret != GNUTLS_E_SUCCESS) {
439
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
440
" %s\n", safer_gnutls_strerror(ret));
441
goto globalfail;
442
}
443
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
444
if(ret != GNUTLS_E_SUCCESS) {
445
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
446
safer_gnutls_strerror(ret));
447
goto globalfail;
448
}
449
450
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
451
452
return 0;
453
454
globalfail:
455
456
gnutls_certificate_free_credentials(mc->cred);
457
gnutls_global_deinit();
458
gnutls_dh_params_deinit(mc->dh_params);
459
return -1;
460
}
461
462
static int init_gnutls_session(mandos_context *mc,
463
gnutls_session_t *session){
464
int ret;
465
/* GnuTLS session creation */
466
ret = gnutls_init(session, GNUTLS_SERVER);
467
if(ret != GNUTLS_E_SUCCESS){
468
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
469
safer_gnutls_strerror(ret));
470
}
471
472
{
473
const char *err;
474
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
475
if(ret != GNUTLS_E_SUCCESS) {
476
fprintf(stderr, "Syntax error at: %s\n", err);
477
fprintf(stderr, "GnuTLS error: %s\n",
478
safer_gnutls_strerror(ret));
479
gnutls_deinit(*session);
480
return -1;
481
}
482
}
483
484
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
485
mc->cred);
486
if(ret != GNUTLS_E_SUCCESS) {
487
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
488
safer_gnutls_strerror(ret));
489
gnutls_deinit(*session);
490
return -1;
491
}
492
493
/* ignore client certificate if any. */
494
gnutls_certificate_server_set_request(*session,
495
GNUTLS_CERT_IGNORE);
496
497
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
498
499
return 0;
500
}
501
502
/* Avahi log function callback */
503
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
504
__attribute__((unused)) const char *txt){}
505
506
/* Called when a Mandos server is found */
507
static int start_mandos_communication(const char *ip, uint16_t port,
508
AvahiIfIndex if_index,
509
mandos_context *mc){
510
int ret, tcp_sd;
511
ssize_t sret;
512
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
513
char *buffer = NULL;
514
char *decrypted_buffer;
515
size_t buffer_length = 0;
516
size_t buffer_capacity = 0;
517
ssize_t decrypted_buffer_size;
518
size_t written;
519
int retval = 0;
520
char interface[IF_NAMESIZE];
521
gnutls_session_t session;
522
523
ret = init_gnutls_session(mc, &session);
524
if(ret != 0){
525
return -1;
526
}
527
528
if(debug){
529
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
530
"\n", ip, port);
531
}
532
533
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
534
if(tcp_sd < 0) {
535
perror("socket");
536
return -1;
537
}
538
539
if(debug){
540
if(if_indextoname((unsigned int)if_index, interface) == NULL){
541
perror("if_indextoname");
542
return -1;
543
}
544
fprintf(stderr, "Binding to interface %s\n", interface);
545
}
546
547
memset(&to, 0, sizeof(to));
548
to.in6.sin6_family = AF_INET6;
549
/* It would be nice to have a way to detect if we were passed an
550
IPv4 address here. Now we assume an IPv6 address. */
551
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
552
if(ret < 0 ){
553
perror("inet_pton");
554
return -1;
555
}
556
if(ret == 0){
557
fprintf(stderr, "Bad address: %s\n", ip);
558
return -1;
559
}
560
to.in6.sin6_port = htons(port); /* Spurious warnings from
561
-Wconversion and
562
-Wunreachable-code */
563
564
to.in6.sin6_scope_id = (uint32_t)if_index;
565
566
if(debug){
567
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
568
port);
569
char addrstr[INET6_ADDRSTRLEN] = "";
570
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
571
sizeof(addrstr)) == NULL){
572
perror("inet_ntop");
573
} else {
574
if(strcmp(addrstr, ip) != 0){
575
fprintf(stderr, "Canonical address form: %s\n", addrstr);
576
}
577
}
578
}
579
580
ret = connect(tcp_sd, &to.in, sizeof(to));
581
if(ret < 0){
582
perror("connect");
583
return -1;
584
}
585
586
const char *out = mandos_protocol_version;
587
written = 0;
588
while(true){
589
size_t out_size = strlen(out);
590
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
591
out_size - written));
592
if(ret == -1){
593
perror("write");
594
retval = -1;
595
goto mandos_end;
596
}
597
written += (size_t)ret;
598
if(written < out_size){
599
continue;
600
} else {
601
if(out == mandos_protocol_version){
602
written = 0;
603
out = "\r\n";
604
} else {
605
break;
606
}
607
}
608
}
609
610
if(debug){
611
fprintf(stderr, "Establishing TLS session with %s\n", ip);
612
}
613
614
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
615
616
do{
617
ret = gnutls_handshake(session);
618
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
619
620
if(ret != GNUTLS_E_SUCCESS){
621
if(debug){
622
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
623
gnutls_perror(ret);
624
}
625
retval = -1;
626
goto mandos_end;
627
}
628
629
/* Read OpenPGP packet that contains the wanted password */
630
631
if(debug){
632
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
633
ip);
634
}
635
636
while(true){
637
buffer_capacity = adjustbuffer(&buffer, buffer_length,
638
buffer_capacity);
639
if(buffer_capacity == 0){
640
perror("adjustbuffer");
641
retval = -1;
642
goto mandos_end;
643
}
644
645
sret = gnutls_record_recv(session, buffer+buffer_length,
646
BUFFER_SIZE);
647
if(sret == 0){
648
break;
649
}
650
if(sret < 0){
651
switch(sret){
652
case GNUTLS_E_INTERRUPTED:
653
case GNUTLS_E_AGAIN:
654
break;
655
case GNUTLS_E_REHANDSHAKE:
656
do{
657
ret = gnutls_handshake(session);
658
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
659
if(ret < 0){
660
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
661
gnutls_perror(ret);
662
retval = -1;
663
goto mandos_end;
664
}
665
break;
666
default:
667
fprintf(stderr, "Unknown error while reading data from"
668
" encrypted session with Mandos server\n");
669
retval = -1;
670
gnutls_bye(session, GNUTLS_SHUT_RDWR);
671
goto mandos_end;
672
}
673
} else {
674
buffer_length += (size_t) sret;
675
}
676
}
677
678
if(debug){
679
fprintf(stderr, "Closing TLS session\n");
680
}
681
682
gnutls_bye(session, GNUTLS_SHUT_RDWR);
683
684
if(buffer_length > 0){
685
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
686
buffer_length,
687
&decrypted_buffer);
688
if(decrypted_buffer_size >= 0){
689
written = 0;
690
while(written < (size_t) decrypted_buffer_size){
691
ret = (int)fwrite(decrypted_buffer + written, 1,
692
(size_t)decrypted_buffer_size - written,
693
stdout);
694
if(ret == 0 and ferror(stdout)){
695
if(debug){
696
fprintf(stderr, "Error writing encrypted data: %s\n",
697
strerror(errno));
698
}
699
retval = -1;
700
break;
701
}
702
written += (size_t)ret;
703
}
704
free(decrypted_buffer);
705
} else {
706
retval = -1;
707
}
708
} else {
709
retval = -1;
710
}
711
712
/* Shutdown procedure */
713
714
mandos_end:
715
free(buffer);
716
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
717
if(ret == -1){
718
perror("close");
719
}
720
gnutls_deinit(session);
721
return retval;
722
}
723
724
static void resolve_callback(AvahiSServiceResolver *r,
725
AvahiIfIndex interface,
726
AVAHI_GCC_UNUSED AvahiProtocol protocol,
727
AvahiResolverEvent event,
728
const char *name,
729
const char *type,
730
const char *domain,
731
const char *host_name,
732
const AvahiAddress *address,
733
uint16_t port,
734
AVAHI_GCC_UNUSED AvahiStringList *txt,
735
AVAHI_GCC_UNUSED AvahiLookupResultFlags
736
flags,
737
void* userdata) {
738
mandos_context *mc = userdata;
739
assert(r);
740
741
/* Called whenever a service has been resolved successfully or
742
timed out */
743
744
switch(event) {
745
default:
746
case AVAHI_RESOLVER_FAILURE:
747
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
748
" of type '%s' in domain '%s': %s\n", name, type, domain,
749
avahi_strerror(avahi_server_errno(mc->server)));
750
break;
751
752
case AVAHI_RESOLVER_FOUND:
753
{
754
char ip[AVAHI_ADDRESS_STR_MAX];
755
avahi_address_snprint(ip, sizeof(ip), address);
756
if(debug){
757
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
758
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
759
ip, (intmax_t)interface, port);
760
}
761
int ret = start_mandos_communication(ip, port, interface, mc);
762
if(ret == 0){
763
avahi_simple_poll_quit(mc->simple_poll);
764
}
765
}
766
}
767
avahi_s_service_resolver_free(r);
768
}
769
770
static void browse_callback( AvahiSServiceBrowser *b,
771
AvahiIfIndex interface,
772
AvahiProtocol protocol,
773
AvahiBrowserEvent event,
774
const char *name,
775
const char *type,
776
const char *domain,
777
AVAHI_GCC_UNUSED AvahiLookupResultFlags
778
flags,
779
void* userdata) {
780
mandos_context *mc = userdata;
781
assert(b);
782
783
/* Called whenever a new services becomes available on the LAN or
784
is removed from the LAN */
785
786
switch(event) {
787
default:
788
case AVAHI_BROWSER_FAILURE:
789
790
fprintf(stderr, "(Avahi browser) %s\n",
791
avahi_strerror(avahi_server_errno(mc->server)));
792
avahi_simple_poll_quit(mc->simple_poll);
793
return;
794
795
case AVAHI_BROWSER_NEW:
796
/* We ignore the returned Avahi resolver object. In the callback
797
function we free it. If the Avahi server is terminated before
798
the callback function is called the Avahi server will free the
799
resolver for us. */
800
801
if(!(avahi_s_service_resolver_new(mc->server, interface,
802
protocol, name, type, domain,
803
AVAHI_PROTO_INET6, 0,
804
resolve_callback, mc)))
805
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
806
name, avahi_strerror(avahi_server_errno(mc->server)));
807
break;
808
809
case AVAHI_BROWSER_REMOVE:
810
break;
811
812
case AVAHI_BROWSER_ALL_FOR_NOW:
813
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
if(debug){
815
fprintf(stderr, "No Mandos server found, still searching...\n");
816
}
817
break;
818
}
819
}
820
821
int main(int argc, char *argv[]){
822
AvahiSServiceBrowser *sb = NULL;
823
int error;
824
int ret;
825
intmax_t tmpmax;
826
int numchars;
827
int exitcode = EXIT_SUCCESS;
828
const char *interface = "eth0";
829
struct ifreq network;
830
int sd;
831
uid_t uid;
832
gid_t gid;
833
char *connect_to = NULL;
834
char tempdir[] = "/tmp/mandosXXXXXX";
835
bool tempdir_created = false;
836
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
837
const char *seckey = PATHDIR "/" SECKEY;
838
const char *pubkey = PATHDIR "/" PUBKEY;
839
840
mandos_context mc = { .simple_poll = NULL, .server = NULL,
841
.dh_bits = 1024, .priority = "SECURE256"
842
":!CTYPE-X.509:+CTYPE-OPENPGP" };
843
bool gnutls_initialized = false;
844
bool gpgme_initialized = false;
845
846
{
847
struct argp_option options[] = {
848
{ .name = "debug", .key = 128,
849
.doc = "Debug mode", .group = 3 },
850
{ .name = "connect", .key = 'c',
851
.arg = "ADDRESS:PORT",
852
.doc = "Connect directly to a specific Mandos server",
853
.group = 1 },
854
{ .name = "interface", .key = 'i',
855
.arg = "NAME",
856
.doc = "Interface that will be used to search for Mandos"
857
" servers",
858
.group = 1 },
859
{ .name = "seckey", .key = 's',
860
.arg = "FILE",
861
.doc = "OpenPGP secret key file base name",
862
.group = 1 },
863
{ .name = "pubkey", .key = 'p',
864
.arg = "FILE",
865
.doc = "OpenPGP public key file base name",
866
.group = 2 },
867
{ .name = "dh-bits", .key = 129,
868
.arg = "BITS",
869
.doc = "Bit length of the prime number used in the"
870
" Diffie-Hellman key exchange",
871
.group = 2 },
872
{ .name = "priority", .key = 130,
873
.arg = "STRING",
874
.doc = "GnuTLS priority string for the TLS handshake",
875
.group = 1 },
876
{ .name = NULL }
877
};
878
879
error_t parse_opt(int key, char *arg,
880
struct argp_state *state) {
881
switch(key) {
882
case 128: /* --debug */
883
debug = true;
884
break;
885
case 'c': /* --connect */
886
connect_to = arg;
887
break;
888
case 'i': /* --interface */
889
interface = arg;
890
break;
891
case 's': /* --seckey */
892
seckey = arg;
893
break;
894
case 'p': /* --pubkey */
895
pubkey = arg;
896
break;
897
case 129: /* --dh-bits */
898
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
899
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
900
or arg[numchars] != '\0'){
901
fprintf(stderr, "Bad number of DH bits\n");
902
exit(EXIT_FAILURE);
903
}
904
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
905
break;
906
case 130: /* --priority */
907
mc.priority = arg;
908
break;
909
case ARGP_KEY_ARG:
910
argp_usage(state);
911
case ARGP_KEY_END:
912
break;
913
default:
914
return ARGP_ERR_UNKNOWN;
915
}
916
return 0;
917
}
918
919
struct argp argp = { .options = options, .parser = parse_opt,
920
.args_doc = "",
921
.doc = "Mandos client -- Get and decrypt"
922
" passwords from a Mandos server" };
923
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
924
if(ret == ARGP_ERR_UNKNOWN){
925
fprintf(stderr, "Unknown error while parsing arguments\n");
926
exitcode = EXIT_FAILURE;
927
goto end;
928
}
929
}
930
931
/* If the interface is down, bring it up */
932
{
933
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
934
if(sd < 0) {
935
perror("socket");
936
exitcode = EXIT_FAILURE;
937
goto end;
938
}
939
strcpy(network.ifr_name, interface);
940
ret = ioctl(sd, SIOCGIFFLAGS, &network);
941
if(ret == -1){
942
perror("ioctl SIOCGIFFLAGS");
943
exitcode = EXIT_FAILURE;
944
goto end;
945
}
946
if((network.ifr_flags & IFF_UP) == 0){
947
network.ifr_flags |= IFF_UP;
948
ret = ioctl(sd, SIOCSIFFLAGS, &network);
949
if(ret == -1){
950
perror("ioctl SIOCSIFFLAGS");
951
exitcode = EXIT_FAILURE;
952
goto end;
953
}
954
}
955
ret = (int)TEMP_FAILURE_RETRY(close(sd));
956
if(ret == -1){
957
perror("close");
958
}
959
}
960
961
uid = getuid();
962
gid = getgid();
963
964
ret = setuid(uid);
965
if(ret == -1){
966
perror("setuid");
967
}
968
969
setgid(gid);
970
if(ret == -1){
971
perror("setgid");
972
}
973
974
ret = init_gnutls_global(&mc, pubkey, seckey);
975
if(ret == -1){
976
fprintf(stderr, "init_gnutls_global failed\n");
977
exitcode = EXIT_FAILURE;
978
goto end;
979
} else {
980
gnutls_initialized = true;
981
}
982
983
if(mkdtemp(tempdir) == NULL){
984
perror("mkdtemp");
985
goto end;
986
}
987
tempdir_created = true;
988
989
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
990
fprintf(stderr, "init_gpgme failed\n");
991
exitcode = EXIT_FAILURE;
992
goto end;
993
} else {
994
gpgme_initialized = true;
995
}
996
997
if_index = (AvahiIfIndex) if_nametoindex(interface);
998
if(if_index == 0){
999
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1000
exitcode = EXIT_FAILURE;
1001
goto end;
1002
}
1003
1004
if(connect_to != NULL){
1005
/* Connect directly, do not use Zeroconf */
1006
/* (Mainly meant for debugging) */
1007
char *address = strrchr(connect_to, ':');
1008
if(address == NULL){
1009
fprintf(stderr, "No colon in address\n");
1010
exitcode = EXIT_FAILURE;
1011
goto end;
1012
}
1013
uint16_t port;
1014
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1015
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1016
or address[numchars+1] != '\0'){
1017
fprintf(stderr, "Bad port number\n");
1018
exitcode = EXIT_FAILURE;
1019
goto end;
1020
}
1021
port = (uint16_t)tmpmax;
1022
*address = '\0';
1023
address = connect_to;
1024
ret = start_mandos_communication(address, port, if_index, &mc);
1025
if(ret < 0){
1026
exitcode = EXIT_FAILURE;
1027
} else {
1028
exitcode = EXIT_SUCCESS;
1029
}
1030
goto end;
1031
}
1032
1033
if(not debug){
1034
avahi_set_log_function(empty_log);
1035
}
1036
1037
/* Initialize the pseudo-RNG for Avahi */
1038
srand((unsigned int) time(NULL));
1039
1040
/* Allocate main Avahi loop object */
1041
mc.simple_poll = avahi_simple_poll_new();
1042
if(mc.simple_poll == NULL) {
1043
fprintf(stderr, "Avahi: Failed to create simple poll"
1044
" object.\n");
1045
exitcode = EXIT_FAILURE;
1046
goto end;
1047
}
1048
1049
{
1050
AvahiServerConfig config;
1051
/* Do not publish any local Zeroconf records */
1052
avahi_server_config_init(&config);
1053
config.publish_hinfo = 0;
1054
config.publish_addresses = 0;
1055
config.publish_workstation = 0;
1056
config.publish_domain = 0;
1057
1058
/* Allocate a new server */
1059
mc.server = avahi_server_new(avahi_simple_poll_get
1060
(mc.simple_poll), &config, NULL,
1061
NULL, &error);
1062
1063
/* Free the Avahi configuration data */
1064
avahi_server_config_free(&config);
1065
}
1066
1067
/* Check if creating the Avahi server object succeeded */
1068
if(mc.server == NULL) {
1069
fprintf(stderr, "Failed to create Avahi server: %s\n",
1070
avahi_strerror(error));
1071
exitcode = EXIT_FAILURE;
1072
goto end;
1073
}
1074
1075
/* Create the Avahi service browser */
1076
sb = avahi_s_service_browser_new(mc.server, if_index,
1077
AVAHI_PROTO_INET6,
1078
"_mandos._tcp", NULL, 0,
1079
browse_callback, &mc);
1080
if(sb == NULL) {
1081
fprintf(stderr, "Failed to create service browser: %s\n",
1082
avahi_strerror(avahi_server_errno(mc.server)));
1083
exitcode = EXIT_FAILURE;
1084
goto end;
1085
}
1086
1087
/* Run the main loop */
1088
1089
if(debug){
1090
fprintf(stderr, "Starting Avahi loop search\n");
1091
}
1092
1093
avahi_simple_poll_loop(mc.simple_poll);
1094
1095
end:
1096
1097
if(debug){
1098
fprintf(stderr, "%s exiting\n", argv[0]);
1099
}
1100
1101
/* Cleanup things */
1102
if(sb != NULL)
1103
avahi_s_service_browser_free(sb);
1104
1105
if(mc.server != NULL)
1106
avahi_server_free(mc.server);
1107
1108
if(mc.simple_poll != NULL)
1109
avahi_simple_poll_free(mc.simple_poll);
1110
1111
if(gnutls_initialized){
1112
gnutls_certificate_free_credentials(mc.cred);
1113
gnutls_global_deinit();
1114
gnutls_dh_params_deinit(mc.dh_params);
1115
}
1116
1117
if(gpgme_initialized){
1118
gpgme_release(mc.ctx);
1119
}
1120
1121
/* Removes the temp directory used by GPGME */
1122
if(tempdir_created){
1123
DIR *d;
1124
struct dirent *direntry;
1125
d = opendir(tempdir);
1126
if(d == NULL){
1127
if(errno != ENOENT){
1128
perror("opendir");
1129
}
1130
} else {
1131
while(true){
1132
direntry = readdir(d);
1133
if(direntry == NULL){
1134
break;
1135
}
1136
/* Skip "." and ".." */
1137
if(direntry->d_name[0] == '.'
1138
and (direntry->d_name[1] == '\0'
1139
or (direntry->d_name[1] == '.'
1140
and direntry->d_name[2] == '\0'))){
1141
continue;
1142
}
1143
char *fullname = NULL;
1144
ret = asprintf(&fullname, "%s/%s", tempdir,
1145
direntry->d_name);
1146
if(ret < 0){
1147
perror("asprintf");
1148
continue;
1149
}
1150
ret = remove(fullname);
1151
if(ret == -1){
1152
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1153
strerror(errno));
1154
}
1155
free(fullname);
1156
}
1157
closedir(d);
1158
}
1159
ret = rmdir(tempdir);
1160
if(ret == -1 and errno != ENOENT){
1161
perror("rmdir");
1162
}
1163
}
1164
1165
return exitcode;
1166
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0