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- Committer: Teddy Hogeborn
- Date: 2008-01-18 21:23:46 UTC
- mfrom: (2.1.1 Project)
- Revision ID: teddy@fukt.bsnet.se-20080118212346-qo103d6o8r7xs4za
Merged from Björn.
- files added:
- ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- plugins.d
- files renamed:
- clients.conf => mandos-clients.conf
- mandos => server.py
- 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
#include <stdint.h> /* uint16_t, uint32_t */
41
#include <stddef.h> /* NULL, size_t, ssize_t */
42
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
43
srand() */
44
#include <stdbool.h> /* bool, true */
45
#include <string.h> /* memset(), strcmp(), strlen(),
46
strerror(), asprintf(), strcpy() */
47
#include <sys/ioctl.h> /* ioctl */
48
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
49
sockaddr_in6, PF_INET6,
50
SOCK_STREAM, INET6_ADDRSTRLEN,
51
uid_t, gid_t, open(), opendir(), DIR */
52
#include <sys/stat.h> /* open() */
53
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
54
struct in6_addr, inet_pton(),
55
connect() */
56
#include <fcntl.h> /* open() */
57
#include <dirent.h> /* opendir(), struct dirent, readdir() */
58
#include <inttypes.h> /* PRIu16, SCNu16 */
59
#include <assert.h> /* assert() */
60
#include <errno.h> /* perror(), errno */
61
#include <time.h> /* time() */
62
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
63
SIOCSIFFLAGS, if_indextoname(),
64
if_nametoindex(), IF_NAMESIZE */
65
#include <netinet/in.h>
66
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
67
getuid(), getgid(), setuid(),
68
setgid() */
69
#include <arpa/inet.h> /* inet_pton(), htons */
70
#include <iso646.h> /* not, and, or */
71
#include <argp.h> /* struct argp_option, error_t, struct
72
argp_state, struct argp,
73
argp_parse(), ARGP_KEY_ARG,
74
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
75
76
/* Avahi */
77
/* All Avahi types, constants and functions
78
Avahi*, avahi_*,
79
AVAHI_* */
80
#include <avahi-core/core.h>
81
#include <avahi-core/lookup.h>
82
#include <avahi-core/log.h>
83
#include <avahi-common/simple-watch.h>
84
#include <avahi-common/malloc.h>
85
#include <avahi-common/error.h>
86
87
/* GnuTLS */
88
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
89
functions:
90
gnutls_*
91
init_gnutls_session(),
92
GNUTLS_* */
93
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
94
GNUTLS_OPENPGP_FMT_BASE64 */
95
96
/* GPGME */
97
#include <gpgme.h> /* All GPGME types, constants and
98
functions:
99
gpgme_*
100
GPGME_PROTOCOL_OpenPGP,
101
GPG_ERR_NO_* */
102
103
#define BUFFER_SIZE 256
104
105
#define PATHDIR "/conf/conf.d/mandos"
106
#define SECKEY "seckey.txt"
107
#define PUBKEY "pubkey.txt"
108
109
bool debug = false;
110
static const char mandos_protocol_version[] = "1";
111
const char *argp_program_version = "mandos-client " VERSION;
112
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
113
114
/* Used for passing in values through the Avahi callback functions */
115
typedef struct {
116
AvahiSimplePoll *simple_poll;
117
AvahiServer *server;
118
gnutls_certificate_credentials_t cred;
119
unsigned int dh_bits;
120
gnutls_dh_params_t dh_params;
121
const char *priority;
122
gpgme_ctx_t ctx;
123
} mandos_context;
124
125
/*
126
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
127
* "buffer_capacity" is how much is currently allocated,
128
* "buffer_length" is how much is already used.
129
*/
130
size_t adjustbuffer(char **buffer, size_t buffer_length,
131
size_t buffer_capacity){
132
if (buffer_length + BUFFER_SIZE > buffer_capacity){
133
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
134
if (buffer == NULL){
135
return 0;
136
}
137
buffer_capacity += BUFFER_SIZE;
138
}
139
return buffer_capacity;
140
}
141
142
/*
143
* Initialize GPGME.
144
*/
145
static bool init_gpgme(mandos_context *mc, const char *seckey,
146
const char *pubkey, const char *tempdir){
147
int ret;
148
gpgme_error_t rc;
149
gpgme_engine_info_t engine_info;
150
151
152
/*
153
* Helper function to insert pub and seckey to the enigne keyring.
154
*/
155
bool import_key(const char *filename){
156
int fd;
157
gpgme_data_t pgp_data;
158
159
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
160
if(fd == -1){
161
perror("open");
162
return false;
163
}
164
165
rc = gpgme_data_new_from_fd(&pgp_data, fd);
166
if (rc != GPG_ERR_NO_ERROR){
167
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
168
gpgme_strsource(rc), gpgme_strerror(rc));
169
return false;
170
}
171
172
rc = gpgme_op_import(mc->ctx, pgp_data);
173
if (rc != GPG_ERR_NO_ERROR){
174
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
176
return false;
177
}
178
179
ret = (int)TEMP_FAILURE_RETRY(close(fd));
180
if(ret == -1){
181
perror("close");
182
}
183
gpgme_data_release(pgp_data);
184
return true;
185
}
186
187
if (debug){
188
fprintf(stderr, "Initialize gpgme\n");
189
}
190
191
/* Init GPGME */
192
gpgme_check_version(NULL);
193
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
194
if (rc != GPG_ERR_NO_ERROR){
195
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
196
gpgme_strsource(rc), gpgme_strerror(rc));
197
return false;
198
}
199
200
/* Set GPGME home directory for the OpenPGP engine only */
201
rc = gpgme_get_engine_info (&engine_info);
202
if (rc != GPG_ERR_NO_ERROR){
203
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
204
gpgme_strsource(rc), gpgme_strerror(rc));
205
return false;
206
}
207
while(engine_info != NULL){
208
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
209
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
210
engine_info->file_name, tempdir);
211
break;
212
}
213
engine_info = engine_info->next;
214
}
215
if(engine_info == NULL){
216
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
217
return false;
218
}
219
220
/* Create new GPGME "context" */
221
rc = gpgme_new(&(mc->ctx));
222
if (rc != GPG_ERR_NO_ERROR){
223
fprintf(stderr, "bad gpgme_new: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
225
return false;
226
}
227
228
if (not import_key(pubkey) or not import_key(seckey)){
229
return false;
230
}
231
232
return true;
233
}
234
235
/*
236
* Decrypt OpenPGP data.
237
* Returns -1 on error
238
*/
239
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
240
const char *cryptotext,
241
size_t crypto_size,
242
char **plaintext){
243
gpgme_data_t dh_crypto, dh_plain;
244
gpgme_error_t rc;
245
ssize_t ret;
246
size_t plaintext_capacity = 0;
247
ssize_t plaintext_length = 0;
248
249
if (debug){
250
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
251
}
252
253
/* Create new GPGME data buffer from memory cryptotext */
254
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
255
0);
256
if (rc != GPG_ERR_NO_ERROR){
257
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
258
gpgme_strsource(rc), gpgme_strerror(rc));
259
return -1;
260
}
261
262
/* Create new empty GPGME data buffer for the plaintext */
263
rc = gpgme_data_new(&dh_plain);
264
if (rc != GPG_ERR_NO_ERROR){
265
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
266
gpgme_strsource(rc), gpgme_strerror(rc));
267
gpgme_data_release(dh_crypto);
268
return -1;
269
}
270
271
/* Decrypt data from the cryptotext data buffer to the plaintext
272
data buffer */
273
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
274
if (rc != GPG_ERR_NO_ERROR){
275
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
276
gpgme_strsource(rc), gpgme_strerror(rc));
277
plaintext_length = -1;
278
if (debug){
279
gpgme_decrypt_result_t result;
280
result = gpgme_op_decrypt_result(mc->ctx);
281
if (result == NULL){
282
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
283
} else {
284
fprintf(stderr, "Unsupported algorithm: %s\n",
285
result->unsupported_algorithm);
286
fprintf(stderr, "Wrong key usage: %u\n",
287
result->wrong_key_usage);
288
if(result->file_name != NULL){
289
fprintf(stderr, "File name: %s\n", result->file_name);
290
}
291
gpgme_recipient_t recipient;
292
recipient = result->recipients;
293
if(recipient){
294
while(recipient != NULL){
295
fprintf(stderr, "Public key algorithm: %s\n",
296
gpgme_pubkey_algo_name(recipient->pubkey_algo));
297
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
298
fprintf(stderr, "Secret key available: %s\n",
299
recipient->status == GPG_ERR_NO_SECKEY
300
? "No" : "Yes");
301
recipient = recipient->next;
302
}
303
}
304
}
305
}
306
goto decrypt_end;
307
}
308
309
if(debug){
310
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
311
}
312
313
/* Seek back to the beginning of the GPGME plaintext data buffer */
314
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
315
perror("gpgme_data_seek");
316
plaintext_length = -1;
317
goto decrypt_end;
318
}
319
320
*plaintext = NULL;
321
while(true){
322
plaintext_capacity = adjustbuffer(plaintext,
323
(size_t)plaintext_length,
324
plaintext_capacity);
325
if (plaintext_capacity == 0){
326
perror("adjustbuffer");
327
plaintext_length = -1;
328
goto decrypt_end;
329
}
330
331
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
332
BUFFER_SIZE);
333
/* Print the data, if any */
334
if (ret == 0){
335
/* EOF */
336
break;
337
}
338
if(ret < 0){
339
perror("gpgme_data_read");
340
plaintext_length = -1;
341
goto decrypt_end;
342
}
343
plaintext_length += ret;
344
}
345
346
if(debug){
347
fprintf(stderr, "Decrypted password is: ");
348
for(ssize_t i = 0; i < plaintext_length; i++){
349
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
350
}
351
fprintf(stderr, "\n");
352
}
353
354
decrypt_end:
355
356
/* Delete the GPGME cryptotext data buffer */
357
gpgme_data_release(dh_crypto);
358
359
/* Delete the GPGME plaintext data buffer */
360
gpgme_data_release(dh_plain);
361
return plaintext_length;
362
}
363
364
static const char * safer_gnutls_strerror (int value) {
365
const char *ret = gnutls_strerror (value); /* Spurious warning */
366
if (ret == NULL)
367
ret = "(unknown)";
368
return ret;
369
}
370
371
/* GnuTLS log function callback */
372
static void debuggnutls(__attribute__((unused)) int level,
373
const char* string){
374
fprintf(stderr, "GnuTLS: %s", string);
375
}
376
377
static int init_gnutls_global(mandos_context *mc,
378
const char *pubkeyfilename,
379
const char *seckeyfilename){
380
int ret;
381
382
if(debug){
383
fprintf(stderr, "Initializing GnuTLS\n");
384
}
385
386
ret = gnutls_global_init();
387
if (ret != GNUTLS_E_SUCCESS) {
388
fprintf (stderr, "GnuTLS global_init: %s\n",
389
safer_gnutls_strerror(ret));
390
return -1;
391
}
392
393
if (debug){
394
/* "Use a log level over 10 to enable all debugging options."
395
* - GnuTLS manual
396
*/
397
gnutls_global_set_log_level(11);
398
gnutls_global_set_log_function(debuggnutls);
399
}
400
401
/* OpenPGP credentials */
402
gnutls_certificate_allocate_credentials(&mc->cred);
403
if (ret != GNUTLS_E_SUCCESS){
404
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
405
warning */
406
safer_gnutls_strerror(ret));
407
gnutls_global_deinit ();
408
return -1;
409
}
410
411
if(debug){
412
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
413
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
414
seckeyfilename);
415
}
416
417
ret = gnutls_certificate_set_openpgp_key_file
418
(mc->cred, pubkeyfilename, seckeyfilename,
419
GNUTLS_OPENPGP_FMT_BASE64);
420
if (ret != GNUTLS_E_SUCCESS) {
421
fprintf(stderr,
422
"Error[%d] while reading the OpenPGP key pair ('%s',"
423
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
424
fprintf(stderr, "The GnuTLS error is: %s\n",
425
safer_gnutls_strerror(ret));
426
goto globalfail;
427
}
428
429
/* GnuTLS server initialization */
430
ret = gnutls_dh_params_init(&mc->dh_params);
431
if (ret != GNUTLS_E_SUCCESS) {
432
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
433
" %s\n", safer_gnutls_strerror(ret));
434
goto globalfail;
435
}
436
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
437
if (ret != GNUTLS_E_SUCCESS) {
438
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
439
safer_gnutls_strerror(ret));
440
goto globalfail;
441
}
442
443
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
444
445
return 0;
446
447
globalfail:
448
449
gnutls_certificate_free_credentials(mc->cred);
450
gnutls_global_deinit();
451
gnutls_dh_params_deinit(mc->dh_params);
452
return -1;
453
}
454
455
static int init_gnutls_session(mandos_context *mc,
456
gnutls_session_t *session){
457
int ret;
458
/* GnuTLS session creation */
459
ret = gnutls_init(session, GNUTLS_SERVER);
460
if (ret != GNUTLS_E_SUCCESS){
461
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
462
safer_gnutls_strerror(ret));
463
}
464
465
{
466
const char *err;
467
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
468
if (ret != GNUTLS_E_SUCCESS) {
469
fprintf(stderr, "Syntax error at: %s\n", err);
470
fprintf(stderr, "GnuTLS error: %s\n",
471
safer_gnutls_strerror(ret));
472
gnutls_deinit (*session);
473
return -1;
474
}
475
}
476
477
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
478
mc->cred);
479
if (ret != GNUTLS_E_SUCCESS) {
480
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
481
safer_gnutls_strerror(ret));
482
gnutls_deinit (*session);
483
return -1;
484
}
485
486
/* ignore client certificate if any. */
487
gnutls_certificate_server_set_request (*session,
488
GNUTLS_CERT_IGNORE);
489
490
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
491
492
return 0;
493
}
494
495
/* Avahi log function callback */
496
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
497
__attribute__((unused)) const char *txt){}
498
499
/* Called when a Mandos server is found */
500
static int start_mandos_communication(const char *ip, uint16_t port,
501
AvahiIfIndex if_index,
502
mandos_context *mc){
503
int ret, tcp_sd;
504
ssize_t sret;
505
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
506
char *buffer = NULL;
507
char *decrypted_buffer;
508
size_t buffer_length = 0;
509
size_t buffer_capacity = 0;
510
ssize_t decrypted_buffer_size;
511
size_t written;
512
int retval = 0;
513
char interface[IF_NAMESIZE];
514
gnutls_session_t session;
515
516
ret = init_gnutls_session (mc, &session);
517
if (ret != 0){
518
return -1;
519
}
520
521
if(debug){
522
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
523
"\n", ip, port);
524
}
525
526
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
527
if(tcp_sd < 0) {
528
perror("socket");
529
return -1;
530
}
531
532
if(debug){
533
if(if_indextoname((unsigned int)if_index, interface) == NULL){
534
perror("if_indextoname");
535
return -1;
536
}
537
fprintf(stderr, "Binding to interface %s\n", interface);
538
}
539
540
memset(&to, 0, sizeof(to));
541
to.in6.sin6_family = AF_INET6;
542
/* It would be nice to have a way to detect if we were passed an
543
IPv4 address here. Now we assume an IPv6 address. */
544
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
545
if (ret < 0 ){
546
perror("inet_pton");
547
return -1;
548
}
549
if(ret == 0){
550
fprintf(stderr, "Bad address: %s\n", ip);
551
return -1;
552
}
553
to.in6.sin6_port = htons(port); /* Spurious warning */
554
555
to.in6.sin6_scope_id = (uint32_t)if_index;
556
557
if(debug){
558
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
559
port);
560
char addrstr[INET6_ADDRSTRLEN] = "";
561
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
562
sizeof(addrstr)) == NULL){
563
perror("inet_ntop");
564
} else {
565
if(strcmp(addrstr, ip) != 0){
566
fprintf(stderr, "Canonical address form: %s\n", addrstr);
567
}
568
}
569
}
570
571
ret = connect(tcp_sd, &to.in, sizeof(to));
572
if (ret < 0){
573
perror("connect");
574
return -1;
575
}
576
577
const char *out = mandos_protocol_version;
578
written = 0;
579
while (true){
580
size_t out_size = strlen(out);
581
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
582
out_size - written));
583
if (ret == -1){
584
perror("write");
585
retval = -1;
586
goto mandos_end;
587
}
588
written += (size_t)ret;
589
if(written < out_size){
590
continue;
591
} else {
592
if (out == mandos_protocol_version){
593
written = 0;
594
out = "\r\n";
595
} else {
596
break;
597
}
598
}
599
}
600
601
if(debug){
602
fprintf(stderr, "Establishing TLS session with %s\n", ip);
603
}
604
605
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
606
607
do{
608
ret = gnutls_handshake (session);
609
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
610
611
if (ret != GNUTLS_E_SUCCESS){
612
if(debug){
613
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
614
gnutls_perror (ret);
615
}
616
retval = -1;
617
goto mandos_end;
618
}
619
620
/* Read OpenPGP packet that contains the wanted password */
621
622
if(debug){
623
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
624
ip);
625
}
626
627
while(true){
628
buffer_capacity = adjustbuffer(&buffer, buffer_length,
629
buffer_capacity);
630
if (buffer_capacity == 0){
631
perror("adjustbuffer");
632
retval = -1;
633
goto mandos_end;
634
}
635
636
sret = gnutls_record_recv(session, buffer+buffer_length,
637
BUFFER_SIZE);
638
if (sret == 0){
639
break;
640
}
641
if (sret < 0){
642
switch(sret){
643
case GNUTLS_E_INTERRUPTED:
644
case GNUTLS_E_AGAIN:
645
break;
646
case GNUTLS_E_REHANDSHAKE:
647
do{
648
ret = gnutls_handshake (session);
649
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
650
if (ret < 0){
651
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
652
gnutls_perror (ret);
653
retval = -1;
654
goto mandos_end;
655
}
656
break;
657
default:
658
fprintf(stderr, "Unknown error while reading data from"
659
" encrypted session with Mandos server\n");
660
retval = -1;
661
gnutls_bye (session, GNUTLS_SHUT_RDWR);
662
goto mandos_end;
663
}
664
} else {
665
buffer_length += (size_t) sret;
666
}
667
}
668
669
if(debug){
670
fprintf(stderr, "Closing TLS session\n");
671
}
672
673
gnutls_bye (session, GNUTLS_SHUT_RDWR);
674
675
if (buffer_length > 0){
676
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
677
buffer_length,
678
&decrypted_buffer);
679
if (decrypted_buffer_size >= 0){
680
written = 0;
681
while(written < (size_t) decrypted_buffer_size){
682
ret = (int)fwrite (decrypted_buffer + written, 1,
683
(size_t)decrypted_buffer_size - written,
684
stdout);
685
if(ret == 0 and ferror(stdout)){
686
if(debug){
687
fprintf(stderr, "Error writing encrypted data: %s\n",
688
strerror(errno));
689
}
690
retval = -1;
691
break;
692
}
693
written += (size_t)ret;
694
}
695
free(decrypted_buffer);
696
} else {
697
retval = -1;
698
}
699
} else {
700
retval = -1;
701
}
702
703
/* Shutdown procedure */
704
705
mandos_end:
706
free(buffer);
707
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
708
if(ret == -1){
709
perror("close");
710
}
711
gnutls_deinit (session);
712
return retval;
713
}
714
715
static void resolve_callback(AvahiSServiceResolver *r,
716
AvahiIfIndex interface,
717
AVAHI_GCC_UNUSED AvahiProtocol protocol,
718
AvahiResolverEvent event,
719
const char *name,
720
const char *type,
721
const char *domain,
722
const char *host_name,
723
const AvahiAddress *address,
724
uint16_t port,
725
AVAHI_GCC_UNUSED AvahiStringList *txt,
726
AVAHI_GCC_UNUSED AvahiLookupResultFlags
727
flags,
728
void* userdata) {
729
mandos_context *mc = userdata;
730
assert(r);
731
732
/* Called whenever a service has been resolved successfully or
733
timed out */
734
735
switch (event) {
736
default:
737
case AVAHI_RESOLVER_FAILURE:
738
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
739
" of type '%s' in domain '%s': %s\n", name, type, domain,
740
avahi_strerror(avahi_server_errno(mc->server)));
741
break;
742
743
case AVAHI_RESOLVER_FOUND:
744
{
745
char ip[AVAHI_ADDRESS_STR_MAX];
746
avahi_address_snprint(ip, sizeof(ip), address);
747
if(debug){
748
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
749
PRIu16 ") on port %d\n", name, host_name, ip,
750
interface, port);
751
}
752
int ret = start_mandos_communication(ip, port, interface, mc);
753
if (ret == 0){
754
avahi_simple_poll_quit(mc->simple_poll);
755
}
756
}
757
}
758
avahi_s_service_resolver_free(r);
759
}
760
761
static void browse_callback( AvahiSServiceBrowser *b,
762
AvahiIfIndex interface,
763
AvahiProtocol protocol,
764
AvahiBrowserEvent event,
765
const char *name,
766
const char *type,
767
const char *domain,
768
AVAHI_GCC_UNUSED AvahiLookupResultFlags
769
flags,
770
void* userdata) {
771
mandos_context *mc = userdata;
772
assert(b);
773
774
/* Called whenever a new services becomes available on the LAN or
775
is removed from the LAN */
776
777
switch (event) {
778
default:
779
case AVAHI_BROWSER_FAILURE:
780
781
fprintf(stderr, "(Avahi browser) %s\n",
782
avahi_strerror(avahi_server_errno(mc->server)));
783
avahi_simple_poll_quit(mc->simple_poll);
784
return;
785
786
case AVAHI_BROWSER_NEW:
787
/* We ignore the returned Avahi resolver object. In the callback
788
function we free it. If the Avahi server is terminated before
789
the callback function is called the Avahi server will free the
790
resolver for us. */
791
792
if (!(avahi_s_service_resolver_new(mc->server, interface,
793
protocol, name, type, domain,
794
AVAHI_PROTO_INET6, 0,
795
resolve_callback, mc)))
796
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
797
name, avahi_strerror(avahi_server_errno(mc->server)));
798
break;
799
800
case AVAHI_BROWSER_REMOVE:
801
break;
802
803
case AVAHI_BROWSER_ALL_FOR_NOW:
804
case AVAHI_BROWSER_CACHE_EXHAUSTED:
805
if(debug){
806
fprintf(stderr, "No Mandos server found, still searching...\n");
807
}
808
break;
809
}
810
}
811
812
int main(int argc, char *argv[]){
813
AvahiSServiceBrowser *sb = NULL;
814
int error;
815
int ret;
816
int exitcode = EXIT_SUCCESS;
817
const char *interface = "eth0";
818
struct ifreq network;
819
int sd;
820
uid_t uid;
821
gid_t gid;
822
char *connect_to = NULL;
823
char tempdir[] = "/tmp/mandosXXXXXX";
824
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
825
const char *seckey = PATHDIR "/" SECKEY;
826
const char *pubkey = PATHDIR "/" PUBKEY;
827
828
mandos_context mc = { .simple_poll = NULL, .server = NULL,
829
.dh_bits = 1024, .priority = "SECURE256"
830
":!CTYPE-X.509:+CTYPE-OPENPGP" };
831
bool gnutls_initalized = false;
832
bool gpgme_initalized = false;
833
834
{
835
struct argp_option options[] = {
836
{ .name = "debug", .key = 128,
837
.doc = "Debug mode", .group = 3 },
838
{ .name = "connect", .key = 'c',
839
.arg = "ADDRESS:PORT",
840
.doc = "Connect directly to a specific Mandos server",
841
.group = 1 },
842
{ .name = "interface", .key = 'i',
843
.arg = "NAME",
844
.doc = "Interface that will be used to search for Mandos"
845
" servers",
846
.group = 1 },
847
{ .name = "seckey", .key = 's',
848
.arg = "FILE",
849
.doc = "OpenPGP secret key file base name",
850
.group = 1 },
851
{ .name = "pubkey", .key = 'p',
852
.arg = "FILE",
853
.doc = "OpenPGP public key file base name",
854
.group = 2 },
855
{ .name = "dh-bits", .key = 129,
856
.arg = "BITS",
857
.doc = "Bit length of the prime number used in the"
858
" Diffie-Hellman key exchange",
859
.group = 2 },
860
{ .name = "priority", .key = 130,
861
.arg = "STRING",
862
.doc = "GnuTLS priority string for the TLS handshake",
863
.group = 1 },
864
{ .name = NULL }
865
};
866
867
error_t parse_opt (int key, char *arg,
868
struct argp_state *state) {
869
switch (key) {
870
case 128: /* --debug */
871
debug = true;
872
break;
873
case 'c': /* --connect */
874
connect_to = arg;
875
break;
876
case 'i': /* --interface */
877
interface = arg;
878
break;
879
case 's': /* --seckey */
880
seckey = arg;
881
break;
882
case 'p': /* --pubkey */
883
pubkey = arg;
884
break;
885
case 129: /* --dh-bits */
886
ret = sscanf(arg, "%u", &mc.dh_bits);
887
if(ret != 1){
888
fprintf(stderr, "Bad number of DH bits\n");
889
exit(EXIT_FAILURE);
890
}
891
break;
892
case 130: /* --priority */
893
mc.priority = arg;
894
break;
895
case ARGP_KEY_ARG:
896
argp_usage (state);
897
case ARGP_KEY_END:
898
break;
899
default:
900
return ARGP_ERR_UNKNOWN;
901
}
902
return 0;
903
}
904
905
struct argp argp = { .options = options, .parser = parse_opt,
906
.args_doc = "",
907
.doc = "Mandos client -- Get and decrypt"
908
" passwords from a Mandos server" };
909
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
910
if (ret == ARGP_ERR_UNKNOWN){
911
fprintf(stderr, "Unknown error while parsing arguments\n");
912
exitcode = EXIT_FAILURE;
913
goto end;
914
}
915
}
916
917
/* If the interface is down, bring it up */
918
{
919
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
920
if(sd < 0) {
921
perror("socket");
922
exitcode = EXIT_FAILURE;
923
goto end;
924
}
925
strcpy(network.ifr_name, interface);
926
ret = ioctl(sd, SIOCGIFFLAGS, &network);
927
if(ret == -1){
928
perror("ioctl SIOCGIFFLAGS");
929
exitcode = EXIT_FAILURE;
930
goto end;
931
}
932
if((network.ifr_flags & IFF_UP) == 0){
933
network.ifr_flags |= IFF_UP;
934
ret = ioctl(sd, SIOCSIFFLAGS, &network);
935
if(ret == -1){
936
perror("ioctl SIOCSIFFLAGS");
937
exitcode = EXIT_FAILURE;
938
goto end;
939
}
940
}
941
ret = (int)TEMP_FAILURE_RETRY(close(sd));
942
if(ret == -1){
943
perror("close");
944
}
945
}
946
947
uid = getuid();
948
gid = getgid();
949
950
ret = setuid(uid);
951
if (ret == -1){
952
perror("setuid");
953
}
954
955
setgid(gid);
956
if (ret == -1){
957
perror("setgid");
958
}
959
960
ret = init_gnutls_global(&mc, pubkey, seckey);
961
if (ret == -1){
962
fprintf(stderr, "init_gnutls_global failed\n");
963
exitcode = EXIT_FAILURE;
964
goto end;
965
} else {
966
gnutls_initalized = true;
967
}
968
969
if(mkdtemp(tempdir) == NULL){
970
perror("mkdtemp");
971
tempdir[0] = '\0';
972
goto end;
973
}
974
975
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
976
fprintf(stderr, "gpgme_initalized failed\n");
977
exitcode = EXIT_FAILURE;
978
goto end;
979
} else {
980
gpgme_initalized = true;
981
}
982
983
if_index = (AvahiIfIndex) if_nametoindex(interface);
984
if(if_index == 0){
985
fprintf(stderr, "No such interface: \"%s\"\n", interface);
986
exit(EXIT_FAILURE);
987
}
988
989
if(connect_to != NULL){
990
/* Connect directly, do not use Zeroconf */
991
/* (Mainly meant for debugging) */
992
char *address = strrchr(connect_to, ':');
993
if(address == NULL){
994
fprintf(stderr, "No colon in address\n");
995
exitcode = EXIT_FAILURE;
996
goto end;
997
}
998
uint16_t port;
999
ret = sscanf(address+1, "%" SCNu16, &port);
1000
if(ret != 1){
1001
fprintf(stderr, "Bad port number\n");
1002
exitcode = EXIT_FAILURE;
1003
goto end;
1004
}
1005
*address = '\0';
1006
address = connect_to;
1007
ret = start_mandos_communication(address, port, if_index, &mc);
1008
if(ret < 0){
1009
exitcode = EXIT_FAILURE;
1010
} else {
1011
exitcode = EXIT_SUCCESS;
1012
}
1013
goto end;
1014
}
1015
1016
if (not debug){
1017
avahi_set_log_function(empty_log);
1018
}
1019
1020
/* Initialize the pseudo-RNG for Avahi */
1021
srand((unsigned int) time(NULL));
1022
1023
/* Allocate main Avahi loop object */
1024
mc.simple_poll = avahi_simple_poll_new();
1025
if (mc.simple_poll == NULL) {
1026
fprintf(stderr, "Avahi: Failed to create simple poll"
1027
" object.\n");
1028
exitcode = EXIT_FAILURE;
1029
goto end;
1030
}
1031
1032
{
1033
AvahiServerConfig config;
1034
/* Do not publish any local Zeroconf records */
1035
avahi_server_config_init(&config);
1036
config.publish_hinfo = 0;
1037
config.publish_addresses = 0;
1038
config.publish_workstation = 0;
1039
config.publish_domain = 0;
1040
1041
/* Allocate a new server */
1042
mc.server = avahi_server_new(avahi_simple_poll_get
1043
(mc.simple_poll), &config, NULL,
1044
NULL, &error);
1045
1046
/* Free the Avahi configuration data */
1047
avahi_server_config_free(&config);
1048
}
1049
1050
/* Check if creating the Avahi server object succeeded */
1051
if (mc.server == NULL) {
1052
fprintf(stderr, "Failed to create Avahi server: %s\n",
1053
avahi_strerror(error));
1054
exitcode = EXIT_FAILURE;
1055
goto end;
1056
}
1057
1058
/* Create the Avahi service browser */
1059
sb = avahi_s_service_browser_new(mc.server, if_index,
1060
AVAHI_PROTO_INET6,
1061
"_mandos._tcp", NULL, 0,
1062
browse_callback, &mc);
1063
if (sb == NULL) {
1064
fprintf(stderr, "Failed to create service browser: %s\n",
1065
avahi_strerror(avahi_server_errno(mc.server)));
1066
exitcode = EXIT_FAILURE;
1067
goto end;
1068
}
1069
1070
/* Run the main loop */
1071
1072
if (debug){
1073
fprintf(stderr, "Starting Avahi loop search\n");
1074
}
1075
1076
avahi_simple_poll_loop(mc.simple_poll);
1077
1078
end:
1079
1080
if (debug){
1081
fprintf(stderr, "%s exiting\n", argv[0]);
1082
}
1083
1084
/* Cleanup things */
1085
if (sb != NULL)
1086
avahi_s_service_browser_free(sb);
1087
1088
if (mc.server != NULL)
1089
avahi_server_free(mc.server);
1090
1091
if (mc.simple_poll != NULL)
1092
avahi_simple_poll_free(mc.simple_poll);
1093
1094
if (gnutls_initalized){
1095
gnutls_certificate_free_credentials(mc.cred);
1096
gnutls_global_deinit ();
1097
gnutls_dh_params_deinit(mc.dh_params);
1098
}
1099
1100
if(gpgme_initalized){
1101
gpgme_release(mc.ctx);
1102
}
1103
1104
/* Removes the temp directory used by GPGME */
1105
if(tempdir[0] != '\0'){
1106
DIR *d;
1107
struct dirent *direntry;
1108
d = opendir(tempdir);
1109
if(d == NULL){
1110
if(errno != ENOENT){
1111
perror("opendir");
1112
}
1113
} else {
1114
while(true){
1115
direntry = readdir(d);
1116
if(direntry == NULL){
1117
break;
1118
}
1119
if (direntry->d_type == DT_REG){
1120
char *fullname = NULL;
1121
ret = asprintf(&fullname, "%s/%s", tempdir,
1122
direntry->d_name);
1123
if(ret < 0){
1124
perror("asprintf");
1125
continue;
1126
}
1127
ret = unlink(fullname);
1128
if(ret == -1){
1129
fprintf(stderr, "unlink(\"%s\"): %s",
1130
fullname, strerror(errno));
1131
}
1132
free(fullname);
1133
}
1134
}
1135
closedir(d);
1136
}
1137
ret = rmdir(tempdir);
1138
if(ret == -1 and errno != ENOENT){
1139
perror("rmdir");
1140
}
1141
}
1142
1143
return exitcode;
1144
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0