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- Committer: Björn Påhlsson
- Date: 2007-12-11 23:40:35 UTC
- Revision ID: belorn@braxen-20071211234035-m1nsu41vuzkak69h
Python based server
Added client configfile
Added client configfile
- files added:
- bad-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
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> /* nanosleep(), 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
#ifdef __linux__
79
#include <sys/klog.h> /* klogctl() */
80
#endif
81
82
/* Avahi */
83
/* All Avahi types, constants and functions
84
Avahi*, avahi_*,
85
AVAHI_* */
86
#include <avahi-core/core.h>
87
#include <avahi-core/lookup.h>
88
#include <avahi-core/log.h>
89
#include <avahi-common/simple-watch.h>
90
#include <avahi-common/malloc.h>
91
#include <avahi-common/error.h>
92
93
/* GnuTLS */
94
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
95
functions:
96
gnutls_*
97
init_gnutls_session(),
98
GNUTLS_* */
99
#include <gnutls/openpgp.h>
100
/* gnutls_certificate_set_openpgp_key_file(),
101
GNUTLS_OPENPGP_FMT_BASE64 */
102
103
/* GPGME */
104
#include <gpgme.h> /* All GPGME types, constants and
105
functions:
106
gpgme_*
107
GPGME_PROTOCOL_OpenPGP,
108
GPG_ERR_NO_* */
109
110
#define BUFFER_SIZE 256
111
112
#define PATHDIR "/conf/conf.d/mandos"
113
#define SECKEY "seckey.txt"
114
#define PUBKEY "pubkey.txt"
115
116
bool debug = false;
117
static const char mandos_protocol_version[] = "1";
118
const char *argp_program_version = "mandos-client " VERSION;
119
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
120
121
/* Used for passing in values through the Avahi callback functions */
122
typedef struct {
123
AvahiSimplePoll *simple_poll;
124
AvahiServer *server;
125
gnutls_certificate_credentials_t cred;
126
unsigned int dh_bits;
127
gnutls_dh_params_t dh_params;
128
const char *priority;
129
gpgme_ctx_t ctx;
130
} mandos_context;
131
132
/*
133
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
134
* "buffer_capacity" is how much is currently allocated,
135
* "buffer_length" is how much is already used.
136
*/
137
size_t adjustbuffer(char **buffer, size_t buffer_length,
138
size_t buffer_capacity){
139
if(buffer_length + BUFFER_SIZE > buffer_capacity){
140
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
141
if(buffer == NULL){
142
return 0;
143
}
144
buffer_capacity += BUFFER_SIZE;
145
}
146
return buffer_capacity;
147
}
148
149
/*
150
* Initialize GPGME.
151
*/
152
static bool init_gpgme(mandos_context *mc, const char *seckey,
153
const char *pubkey, const char *tempdir){
154
int ret;
155
gpgme_error_t rc;
156
gpgme_engine_info_t engine_info;
157
158
159
/*
160
* Helper function to insert pub and seckey to the engine keyring.
161
*/
162
bool import_key(const char *filename){
163
int fd;
164
gpgme_data_t pgp_data;
165
166
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
167
if(fd == -1){
168
perror("open");
169
return false;
170
}
171
172
rc = gpgme_data_new_from_fd(&pgp_data, fd);
173
if(rc != GPG_ERR_NO_ERROR){
174
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
176
return false;
177
}
178
179
rc = gpgme_op_import(mc->ctx, pgp_data);
180
if(rc != GPG_ERR_NO_ERROR){
181
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
182
gpgme_strsource(rc), gpgme_strerror(rc));
183
return false;
184
}
185
186
ret = (int)TEMP_FAILURE_RETRY(close(fd));
187
if(ret == -1){
188
perror("close");
189
}
190
gpgme_data_release(pgp_data);
191
return true;
192
}
193
194
if(debug){
195
fprintf(stderr, "Initialize gpgme\n");
196
}
197
198
/* Init GPGME */
199
gpgme_check_version(NULL);
200
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
201
if(rc != GPG_ERR_NO_ERROR){
202
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
203
gpgme_strsource(rc), gpgme_strerror(rc));
204
return false;
205
}
206
207
/* Set GPGME home directory for the OpenPGP engine only */
208
rc = gpgme_get_engine_info(&engine_info);
209
if(rc != GPG_ERR_NO_ERROR){
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
211
gpgme_strsource(rc), gpgme_strerror(rc));
212
return false;
213
}
214
while(engine_info != NULL){
215
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
216
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
217
engine_info->file_name, tempdir);
218
break;
219
}
220
engine_info = engine_info->next;
221
}
222
if(engine_info == NULL){
223
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
224
return false;
225
}
226
227
/* Create new GPGME "context" */
228
rc = gpgme_new(&(mc->ctx));
229
if(rc != GPG_ERR_NO_ERROR){
230
fprintf(stderr, "bad gpgme_new: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
232
return false;
233
}
234
235
if(not import_key(pubkey) or not import_key(seckey)){
236
return false;
237
}
238
239
return true;
240
}
241
242
/*
243
* Decrypt OpenPGP data.
244
* Returns -1 on error
245
*/
246
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
247
const char *cryptotext,
248
size_t crypto_size,
249
char **plaintext){
250
gpgme_data_t dh_crypto, dh_plain;
251
gpgme_error_t rc;
252
ssize_t ret;
253
size_t plaintext_capacity = 0;
254
ssize_t plaintext_length = 0;
255
256
if(debug){
257
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
258
}
259
260
/* Create new GPGME data buffer from memory cryptotext */
261
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
262
0);
263
if(rc != GPG_ERR_NO_ERROR){
264
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
265
gpgme_strsource(rc), gpgme_strerror(rc));
266
return -1;
267
}
268
269
/* Create new empty GPGME data buffer for the plaintext */
270
rc = gpgme_data_new(&dh_plain);
271
if(rc != GPG_ERR_NO_ERROR){
272
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
273
gpgme_strsource(rc), gpgme_strerror(rc));
274
gpgme_data_release(dh_crypto);
275
return -1;
276
}
277
278
/* Decrypt data from the cryptotext data buffer to the plaintext
279
data buffer */
280
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
281
if(rc != GPG_ERR_NO_ERROR){
282
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
283
gpgme_strsource(rc), gpgme_strerror(rc));
284
plaintext_length = -1;
285
if(debug){
286
gpgme_decrypt_result_t result;
287
result = gpgme_op_decrypt_result(mc->ctx);
288
if(result == NULL){
289
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
290
} else {
291
fprintf(stderr, "Unsupported algorithm: %s\n",
292
result->unsupported_algorithm);
293
fprintf(stderr, "Wrong key usage: %u\n",
294
result->wrong_key_usage);
295
if(result->file_name != NULL){
296
fprintf(stderr, "File name: %s\n", result->file_name);
297
}
298
gpgme_recipient_t recipient;
299
recipient = result->recipients;
300
if(recipient){
301
while(recipient != NULL){
302
fprintf(stderr, "Public key algorithm: %s\n",
303
gpgme_pubkey_algo_name(recipient->pubkey_algo));
304
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
305
fprintf(stderr, "Secret key available: %s\n",
306
recipient->status == GPG_ERR_NO_SECKEY
307
? "No" : "Yes");
308
recipient = recipient->next;
309
}
310
}
311
}
312
}
313
goto decrypt_end;
314
}
315
316
if(debug){
317
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
318
}
319
320
/* Seek back to the beginning of the GPGME plaintext data buffer */
321
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
322
perror("gpgme_data_seek");
323
plaintext_length = -1;
324
goto decrypt_end;
325
}
326
327
*plaintext = NULL;
328
while(true){
329
plaintext_capacity = adjustbuffer(plaintext,
330
(size_t)plaintext_length,
331
plaintext_capacity);
332
if(plaintext_capacity == 0){
333
perror("adjustbuffer");
334
plaintext_length = -1;
335
goto decrypt_end;
336
}
337
338
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
339
BUFFER_SIZE);
340
/* Print the data, if any */
341
if(ret == 0){
342
/* EOF */
343
break;
344
}
345
if(ret < 0){
346
perror("gpgme_data_read");
347
plaintext_length = -1;
348
goto decrypt_end;
349
}
350
plaintext_length += ret;
351
}
352
353
if(debug){
354
fprintf(stderr, "Decrypted password is: ");
355
for(ssize_t i = 0; i < plaintext_length; i++){
356
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
357
}
358
fprintf(stderr, "\n");
359
}
360
361
decrypt_end:
362
363
/* Delete the GPGME cryptotext data buffer */
364
gpgme_data_release(dh_crypto);
365
366
/* Delete the GPGME plaintext data buffer */
367
gpgme_data_release(dh_plain);
368
return plaintext_length;
369
}
370
371
static const char * safer_gnutls_strerror(int value){
372
const char *ret = gnutls_strerror(value); /* Spurious warning from
373
-Wunreachable-code */
374
if(ret == NULL)
375
ret = "(unknown)";
376
return ret;
377
}
378
379
/* GnuTLS log function callback */
380
static void debuggnutls(__attribute__((unused)) int level,
381
const char* string){
382
fprintf(stderr, "GnuTLS: %s", string);
383
}
384
385
static int init_gnutls_global(mandos_context *mc,
386
const char *pubkeyfilename,
387
const char *seckeyfilename){
388
int ret;
389
390
if(debug){
391
fprintf(stderr, "Initializing GnuTLS\n");
392
}
393
394
ret = gnutls_global_init();
395
if(ret != GNUTLS_E_SUCCESS){
396
fprintf(stderr, "GnuTLS global_init: %s\n",
397
safer_gnutls_strerror(ret));
398
return -1;
399
}
400
401
if(debug){
402
/* "Use a log level over 10 to enable all debugging options."
403
* - GnuTLS manual
404
*/
405
gnutls_global_set_log_level(11);
406
gnutls_global_set_log_function(debuggnutls);
407
}
408
409
/* OpenPGP credentials */
410
gnutls_certificate_allocate_credentials(&mc->cred);
411
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
413
* from
414
* -Wunreachable-code
415
*/
416
safer_gnutls_strerror(ret));
417
gnutls_global_deinit();
418
return -1;
419
}
420
421
if(debug){
422
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
423
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
424
seckeyfilename);
425
}
426
427
ret = gnutls_certificate_set_openpgp_key_file
428
(mc->cred, pubkeyfilename, seckeyfilename,
429
GNUTLS_OPENPGP_FMT_BASE64);
430
if(ret != GNUTLS_E_SUCCESS){
431
fprintf(stderr,
432
"Error[%d] while reading the OpenPGP key pair ('%s',"
433
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
434
fprintf(stderr, "The GnuTLS error is: %s\n",
435
safer_gnutls_strerror(ret));
436
goto globalfail;
437
}
438
439
/* GnuTLS server initialization */
440
ret = gnutls_dh_params_init(&mc->dh_params);
441
if(ret != GNUTLS_E_SUCCESS){
442
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
443
" %s\n", safer_gnutls_strerror(ret));
444
goto globalfail;
445
}
446
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
447
if(ret != GNUTLS_E_SUCCESS){
448
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
449
safer_gnutls_strerror(ret));
450
goto globalfail;
451
}
452
453
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
454
455
return 0;
456
457
globalfail:
458
459
gnutls_certificate_free_credentials(mc->cred);
460
gnutls_global_deinit();
461
gnutls_dh_params_deinit(mc->dh_params);
462
return -1;
463
}
464
465
static int init_gnutls_session(mandos_context *mc,
466
gnutls_session_t *session){
467
int ret;
468
/* GnuTLS session creation */
469
ret = gnutls_init(session, GNUTLS_SERVER);
470
if(ret != GNUTLS_E_SUCCESS){
471
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
472
safer_gnutls_strerror(ret));
473
}
474
475
{
476
const char *err;
477
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
478
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Syntax error at: %s\n", err);
480
fprintf(stderr, "GnuTLS error: %s\n",
481
safer_gnutls_strerror(ret));
482
gnutls_deinit(*session);
483
return -1;
484
}
485
}
486
487
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
488
mc->cred);
489
if(ret != GNUTLS_E_SUCCESS){
490
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
491
safer_gnutls_strerror(ret));
492
gnutls_deinit(*session);
493
return -1;
494
}
495
496
/* ignore client certificate if any. */
497
gnutls_certificate_server_set_request(*session,
498
GNUTLS_CERT_IGNORE);
499
500
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
501
502
return 0;
503
}
504
505
/* Avahi log function callback */
506
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
507
__attribute__((unused)) const char *txt){}
508
509
/* Called when a Mandos server is found */
510
static int start_mandos_communication(const char *ip, uint16_t port,
511
AvahiIfIndex if_index,
512
mandos_context *mc){
513
int ret, tcp_sd;
514
ssize_t sret;
515
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
516
char *buffer = NULL;
517
char *decrypted_buffer;
518
size_t buffer_length = 0;
519
size_t buffer_capacity = 0;
520
ssize_t decrypted_buffer_size;
521
size_t written;
522
int retval = 0;
523
char interface[IF_NAMESIZE];
524
gnutls_session_t session;
525
526
ret = init_gnutls_session(mc, &session);
527
if(ret != 0){
528
return -1;
529
}
530
531
if(debug){
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
533
"\n", ip, port);
534
}
535
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
537
if(tcp_sd < 0){
538
perror("socket");
539
return -1;
540
}
541
542
if(debug){
543
if(if_indextoname((unsigned int)if_index, interface) == NULL){
544
perror("if_indextoname");
545
return -1;
546
}
547
fprintf(stderr, "Binding to interface %s\n", interface);
548
}
549
550
memset(&to, 0, sizeof(to));
551
to.in6.sin6_family = AF_INET6;
552
/* It would be nice to have a way to detect if we were passed an
553
IPv4 address here. Now we assume an IPv6 address. */
554
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
555
if(ret < 0 ){
556
perror("inet_pton");
557
return -1;
558
}
559
if(ret == 0){
560
fprintf(stderr, "Bad address: %s\n", ip);
561
return -1;
562
}
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
564
-Wconversion and
565
-Wunreachable-code */
566
567
to.in6.sin6_scope_id = (uint32_t)if_index;
568
569
if(debug){
570
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
571
port);
572
char addrstr[INET6_ADDRSTRLEN] = "";
573
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
574
sizeof(addrstr)) == NULL){
575
perror("inet_ntop");
576
} else {
577
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
579
}
580
}
581
}
582
583
ret = connect(tcp_sd, &to.in, sizeof(to));
584
if(ret < 0){
585
perror("connect");
586
return -1;
587
}
588
589
const char *out = mandos_protocol_version;
590
written = 0;
591
while(true){
592
size_t out_size = strlen(out);
593
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
594
out_size - written));
595
if(ret == -1){
596
perror("write");
597
retval = -1;
598
goto mandos_end;
599
}
600
written += (size_t)ret;
601
if(written < out_size){
602
continue;
603
} else {
604
if(out == mandos_protocol_version){
605
written = 0;
606
out = "\r\n";
607
} else {
608
break;
609
}
610
}
611
}
612
613
if(debug){
614
fprintf(stderr, "Establishing TLS session with %s\n", ip);
615
}
616
617
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
618
619
do{
620
ret = gnutls_handshake(session);
621
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
622
623
if(ret != GNUTLS_E_SUCCESS){
624
if(debug){
625
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
626
gnutls_perror(ret);
627
}
628
retval = -1;
629
goto mandos_end;
630
}
631
632
/* Read OpenPGP packet that contains the wanted password */
633
634
if(debug){
635
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
636
ip);
637
}
638
639
while(true){
640
buffer_capacity = adjustbuffer(&buffer, buffer_length,
641
buffer_capacity);
642
if(buffer_capacity == 0){
643
perror("adjustbuffer");
644
retval = -1;
645
goto mandos_end;
646
}
647
648
sret = gnutls_record_recv(session, buffer+buffer_length,
649
BUFFER_SIZE);
650
if(sret == 0){
651
break;
652
}
653
if(sret < 0){
654
switch(sret){
655
case GNUTLS_E_INTERRUPTED:
656
case GNUTLS_E_AGAIN:
657
break;
658
case GNUTLS_E_REHANDSHAKE:
659
do{
660
ret = gnutls_handshake(session);
661
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
662
if(ret < 0){
663
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
664
gnutls_perror(ret);
665
retval = -1;
666
goto mandos_end;
667
}
668
break;
669
default:
670
fprintf(stderr, "Unknown error while reading data from"
671
" encrypted session with Mandos server\n");
672
retval = -1;
673
gnutls_bye(session, GNUTLS_SHUT_RDWR);
674
goto mandos_end;
675
}
676
} else {
677
buffer_length += (size_t) sret;
678
}
679
}
680
681
if(debug){
682
fprintf(stderr, "Closing TLS session\n");
683
}
684
685
gnutls_bye(session, GNUTLS_SHUT_RDWR);
686
687
if(buffer_length > 0){
688
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
689
buffer_length,
690
&decrypted_buffer);
691
if(decrypted_buffer_size >= 0){
692
written = 0;
693
while(written < (size_t) decrypted_buffer_size){
694
ret = (int)fwrite(decrypted_buffer + written, 1,
695
(size_t)decrypted_buffer_size - written,
696
stdout);
697
if(ret == 0 and ferror(stdout)){
698
if(debug){
699
fprintf(stderr, "Error writing encrypted data: %s\n",
700
strerror(errno));
701
}
702
retval = -1;
703
break;
704
}
705
written += (size_t)ret;
706
}
707
free(decrypted_buffer);
708
} else {
709
retval = -1;
710
}
711
} else {
712
retval = -1;
713
}
714
715
/* Shutdown procedure */
716
717
mandos_end:
718
free(buffer);
719
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
720
if(ret == -1){
721
perror("close");
722
}
723
gnutls_deinit(session);
724
return retval;
725
}
726
727
static void resolve_callback(AvahiSServiceResolver *r,
728
AvahiIfIndex interface,
729
AVAHI_GCC_UNUSED AvahiProtocol protocol,
730
AvahiResolverEvent event,
731
const char *name,
732
const char *type,
733
const char *domain,
734
const char *host_name,
735
const AvahiAddress *address,
736
uint16_t port,
737
AVAHI_GCC_UNUSED AvahiStringList *txt,
738
AVAHI_GCC_UNUSED AvahiLookupResultFlags
739
flags,
740
void* userdata){
741
mandos_context *mc = userdata;
742
assert(r);
743
744
/* Called whenever a service has been resolved successfully or
745
timed out */
746
747
switch(event){
748
default:
749
case AVAHI_RESOLVER_FAILURE:
750
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
751
" of type '%s' in domain '%s': %s\n", name, type, domain,
752
avahi_strerror(avahi_server_errno(mc->server)));
753
break;
754
755
case AVAHI_RESOLVER_FOUND:
756
{
757
char ip[AVAHI_ADDRESS_STR_MAX];
758
avahi_address_snprint(ip, sizeof(ip), address);
759
if(debug){
760
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
761
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
762
ip, (intmax_t)interface, port);
763
}
764
int ret = start_mandos_communication(ip, port, interface, mc);
765
if(ret == 0){
766
avahi_simple_poll_quit(mc->simple_poll);
767
}
768
}
769
}
770
avahi_s_service_resolver_free(r);
771
}
772
773
static void browse_callback(AvahiSServiceBrowser *b,
774
AvahiIfIndex interface,
775
AvahiProtocol protocol,
776
AvahiBrowserEvent event,
777
const char *name,
778
const char *type,
779
const char *domain,
780
AVAHI_GCC_UNUSED AvahiLookupResultFlags
781
flags,
782
void* userdata){
783
mandos_context *mc = userdata;
784
assert(b);
785
786
/* Called whenever a new services becomes available on the LAN or
787
is removed from the LAN */
788
789
switch(event){
790
default:
791
case AVAHI_BROWSER_FAILURE:
792
793
fprintf(stderr, "(Avahi browser) %s\n",
794
avahi_strerror(avahi_server_errno(mc->server)));
795
avahi_simple_poll_quit(mc->simple_poll);
796
return;
797
798
case AVAHI_BROWSER_NEW:
799
/* We ignore the returned Avahi resolver object. In the callback
800
function we free it. If the Avahi server is terminated before
801
the callback function is called the Avahi server will free the
802
resolver for us. */
803
804
if(!(avahi_s_service_resolver_new(mc->server, interface,
805
protocol, name, type, domain,
806
AVAHI_PROTO_INET6, 0,
807
resolve_callback, mc)))
808
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
809
name, avahi_strerror(avahi_server_errno(mc->server)));
810
break;
811
812
case AVAHI_BROWSER_REMOVE:
813
break;
814
815
case AVAHI_BROWSER_ALL_FOR_NOW:
816
case AVAHI_BROWSER_CACHE_EXHAUSTED:
817
if(debug){
818
fprintf(stderr, "No Mandos server found, still searching...\n");
819
}
820
break;
821
}
822
}
823
824
int main(int argc, char *argv[]){
825
AvahiSServiceBrowser *sb = NULL;
826
int error;
827
int ret;
828
intmax_t tmpmax;
829
int numchars;
830
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
832
struct ifreq network;
833
int sd;
834
uid_t uid;
835
gid_t gid;
836
char *connect_to = NULL;
837
char tempdir[] = "/tmp/mandosXXXXXX";
838
bool tempdir_created = false;
839
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
const char *seckey = PATHDIR "/" SECKEY;
841
const char *pubkey = PATHDIR "/" PUBKEY;
842
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
846
bool gnutls_initialized = false;
847
bool gpgme_initialized = false;
848
double delay = 2.5;
849
850
{
851
struct argp_option options[] = {
852
{ .name = "debug", .key = 128,
853
.doc = "Debug mode", .group = 3 },
854
{ .name = "connect", .key = 'c',
855
.arg = "ADDRESS:PORT",
856
.doc = "Connect directly to a specific Mandos server",
857
.group = 1 },
858
{ .name = "interface", .key = 'i',
859
.arg = "NAME",
860
.doc = "Interface that will be used to search for Mandos"
861
" servers",
862
.group = 1 },
863
{ .name = "seckey", .key = 's',
864
.arg = "FILE",
865
.doc = "OpenPGP secret key file base name",
866
.group = 1 },
867
{ .name = "pubkey", .key = 'p',
868
.arg = "FILE",
869
.doc = "OpenPGP public key file base name",
870
.group = 2 },
871
{ .name = "dh-bits", .key = 129,
872
.arg = "BITS",
873
.doc = "Bit length of the prime number used in the"
874
" Diffie-Hellman key exchange",
875
.group = 2 },
876
{ .name = "priority", .key = 130,
877
.arg = "STRING",
878
.doc = "GnuTLS priority string for the TLS handshake",
879
.group = 1 },
880
{ .name = "delay", .key = 131,
881
.arg = "SECONDS",
882
.doc = "Maximum delay to wait for interface startup",
883
.group = 2 },
884
{ .name = NULL }
885
};
886
887
error_t parse_opt(int key, char *arg,
888
struct argp_state *state){
889
switch(key){
890
case 128: /* --debug */
891
debug = true;
892
break;
893
case 'c': /* --connect */
894
connect_to = arg;
895
break;
896
case 'i': /* --interface */
897
interface = arg;
898
break;
899
case 's': /* --seckey */
900
seckey = arg;
901
break;
902
case 'p': /* --pubkey */
903
pubkey = arg;
904
break;
905
case 129: /* --dh-bits */
906
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
907
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
908
or arg[numchars] != '\0'){
909
fprintf(stderr, "Bad number of DH bits\n");
910
exit(EXIT_FAILURE);
911
}
912
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
913
break;
914
case 130: /* --priority */
915
mc.priority = arg;
916
break;
917
case 131: /* --delay */
918
ret = sscanf(arg, "%lf%n", &delay, &numchars);
919
if(ret < 1 or arg[numchars] != '\0'){
920
fprintf(stderr, "Bad delay\n");
921
exit(EXIT_FAILURE);
922
}
923
break;
924
case ARGP_KEY_ARG:
925
argp_usage(state);
926
case ARGP_KEY_END:
927
break;
928
default:
929
return ARGP_ERR_UNKNOWN;
930
}
931
return 0;
932
}
933
934
struct argp argp = { .options = options, .parser = parse_opt,
935
.args_doc = "",
936
.doc = "Mandos client -- Get and decrypt"
937
" passwords from a Mandos server" };
938
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
939
if(ret == ARGP_ERR_UNKNOWN){
940
fprintf(stderr, "Unknown error while parsing arguments\n");
941
exitcode = EXIT_FAILURE;
942
goto end;
943
}
944
}
945
946
/* If the interface is down, bring it up */
947
{
948
#ifdef __linux__
949
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
951
ret = klogctl(8, NULL, 5);
952
if(ret == -1){
953
perror("klogctl");
954
}
955
#endif
956
957
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
958
if(sd < 0){
959
perror("socket");
960
exitcode = EXIT_FAILURE;
961
#ifdef __linux__
962
ret = klogctl(7, NULL, 0);
963
if(ret == -1){
964
perror("klogctl");
965
}
966
#endif
967
goto end;
968
}
969
strcpy(network.ifr_name, interface);
970
ret = ioctl(sd, SIOCGIFFLAGS, &network);
971
if(ret == -1){
972
perror("ioctl SIOCGIFFLAGS");
973
#ifdef __linux__
974
ret = klogctl(7, NULL, 0);
975
if(ret == -1){
976
perror("klogctl");
977
}
978
#endif
979
exitcode = EXIT_FAILURE;
980
goto end;
981
}
982
if((network.ifr_flags & IFF_UP) == 0){
983
network.ifr_flags |= IFF_UP;
984
ret = ioctl(sd, SIOCSIFFLAGS, &network);
985
if(ret == -1){
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
988
#ifdef __linux__
989
ret = klogctl(7, NULL, 0);
990
if(ret == -1){
991
perror("klogctl");
992
}
993
#endif
994
goto end;
995
}
996
}
997
/* sleep checking until interface is running */
998
for(int i=0; i < delay * 4; i++){
999
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1000
if(ret == -1){
1001
perror("ioctl SIOCGIFFLAGS");
1002
} else if(network.ifr_flags & IFF_RUNNING){
1003
break;
1004
}
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
1009
}
1010
}
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1012
if(ret == -1){
1013
perror("close");
1014
}
1015
#ifdef __linux__
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1018
if(ret == -1){
1019
perror("klogctl");
1020
}
1021
#endif
1022
}
1023
1024
uid = getuid();
1025
gid = getgid();
1026
1027
setgid(gid);
1028
if(ret == -1){
1029
perror("setgid");
1030
}
1031
1032
ret = setuid(uid);
1033
if(ret == -1){
1034
perror("setuid");
1035
}
1036
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1038
if(ret == -1){
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
1041
goto end;
1042
} else {
1043
gnutls_initialized = true;
1044
}
1045
1046
if(mkdtemp(tempdir) == NULL){
1047
perror("mkdtemp");
1048
goto end;
1049
}
1050
tempdir_created = true;
1051
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
1055
goto end;
1056
} else {
1057
gpgme_initialized = true;
1058
}
1059
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1061
if(if_index == 0){
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;
1064
goto end;
1065
}
1066
1067
if(connect_to != NULL){
1068
/* Connect directly, do not use Zeroconf */
1069
/* (Mainly meant for debugging) */
1070
char *address = strrchr(connect_to, ':');
1071
if(address == NULL){
1072
fprintf(stderr, "No colon in address\n");
1073
exitcode = EXIT_FAILURE;
1074
goto end;
1075
}
1076
uint16_t port;
1077
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1078
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1079
or address[numchars+1] != '\0'){
1080
fprintf(stderr, "Bad port number\n");
1081
exitcode = EXIT_FAILURE;
1082
goto end;
1083
}
1084
port = (uint16_t)tmpmax;
1085
*address = '\0';
1086
address = connect_to;
1087
ret = start_mandos_communication(address, port, if_index, &mc);
1088
if(ret < 0){
1089
exitcode = EXIT_FAILURE;
1090
} else {
1091
exitcode = EXIT_SUCCESS;
1092
}
1093
goto end;
1094
}
1095
1096
if(not debug){
1097
avahi_set_log_function(empty_log);
1098
}
1099
1100
/* Initialize the pseudo-RNG for Avahi */
1101
srand((unsigned int) time(NULL));
1102
1103
/* Allocate main Avahi loop object */
1104
mc.simple_poll = avahi_simple_poll_new();
1105
if(mc.simple_poll == NULL){
1106
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1107
exitcode = EXIT_FAILURE;
1108
goto end;
1109
}
1110
1111
{
1112
AvahiServerConfig config;
1113
/* Do not publish any local Zeroconf records */
1114
avahi_server_config_init(&config);
1115
config.publish_hinfo = 0;
1116
config.publish_addresses = 0;
1117
config.publish_workstation = 0;
1118
config.publish_domain = 0;
1119
1120
/* Allocate a new server */
1121
mc.server = avahi_server_new(avahi_simple_poll_get
1122
(mc.simple_poll), &config, NULL,
1123
NULL, &error);
1124
1125
/* Free the Avahi configuration data */
1126
avahi_server_config_free(&config);
1127
}
1128
1129
/* Check if creating the Avahi server object succeeded */
1130
if(mc.server == NULL){
1131
fprintf(stderr, "Failed to create Avahi server: %s\n",
1132
avahi_strerror(error));
1133
exitcode = EXIT_FAILURE;
1134
goto end;
1135
}
1136
1137
/* Create the Avahi service browser */
1138
sb = avahi_s_service_browser_new(mc.server, if_index,
1139
AVAHI_PROTO_INET6, "_mandos._tcp",
1140
NULL, 0, browse_callback, &mc);
1141
if(sb == NULL){
1142
fprintf(stderr, "Failed to create service browser: %s\n",
1143
avahi_strerror(avahi_server_errno(mc.server)));
1144
exitcode = EXIT_FAILURE;
1145
goto end;
1146
}
1147
1148
/* Run the main loop */
1149
1150
if(debug){
1151
fprintf(stderr, "Starting Avahi loop search\n");
1152
}
1153
1154
avahi_simple_poll_loop(mc.simple_poll);
1155
1156
end:
1157
1158
if(debug){
1159
fprintf(stderr, "%s exiting\n", argv[0]);
1160
}
1161
1162
/* Cleanup things */
1163
if(sb != NULL)
1164
avahi_s_service_browser_free(sb);
1165
1166
if(mc.server != NULL)
1167
avahi_server_free(mc.server);
1168
1169
if(mc.simple_poll != NULL)
1170
avahi_simple_poll_free(mc.simple_poll);
1171
1172
if(gnutls_initialized){
1173
gnutls_certificate_free_credentials(mc.cred);
1174
gnutls_global_deinit();
1175
gnutls_dh_params_deinit(mc.dh_params);
1176
}
1177
1178
if(gpgme_initialized){
1179
gpgme_release(mc.ctx);
1180
}
1181
1182
/* Removes the temp directory used by GPGME */
1183
if(tempdir_created){
1184
DIR *d;
1185
struct dirent *direntry;
1186
d = opendir(tempdir);
1187
if(d == NULL){
1188
if(errno != ENOENT){
1189
perror("opendir");
1190
}
1191
} else {
1192
while(true){
1193
direntry = readdir(d);
1194
if(direntry == NULL){
1195
break;
1196
}
1197
/* Skip "." and ".." */
1198
if(direntry->d_name[0] == '.'
1199
and (direntry->d_name[1] == '\0'
1200
or (direntry->d_name[1] == '.'
1201
and direntry->d_name[2] == '\0'))){
1202
continue;
1203
}
1204
char *fullname = NULL;
1205
ret = asprintf(&fullname, "%s/%s", tempdir,
1206
direntry->d_name);
1207
if(ret < 0){
1208
perror("asprintf");
1209
continue;
1210
}
1211
ret = remove(fullname);
1212
if(ret == -1){
1213
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1214
strerror(errno));
1215
}
1216
free(fullname);
1217
}
1218
closedir(d);
1219
}
1220
ret = rmdir(tempdir);
1221
if(ret == -1 and errno != ENOENT){
1222
perror("rmdir");
1223
}
1224
}
1225
1226
return exitcode;
1227
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0