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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
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
35
#endif
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
38
#endif
39
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
srand(), strtof() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
55
opendir(), DIR */
56
#include <sys/stat.h> /* open() */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
*/
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
63
strtoimax() */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
SIOCSIFFLAGS, if_indextoname(),
69
if_nametoindex(), IF_NAMESIZE */
70
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
72
*/
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), setuid(),
75
setgid() */
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
#include <iso646.h> /* not, or, and */
78
#include <argp.h> /* struct argp_option, error_t, struct
79
argp_state, struct argp,
80
argp_parse(), ARGP_KEY_ARG,
81
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
sigaction(), SIGTERM, sigaction,
84
sig_atomic_t */
85
86
#ifdef __linux__
87
#include <sys/klog.h> /* klogctl() */
88
#endif /* __linux__ */
89
90
/* Avahi */
91
/* All Avahi types, constants and functions
92
Avahi*, avahi_*,
93
AVAHI_* */
94
#include <avahi-core/core.h>
95
#include <avahi-core/lookup.h>
96
#include <avahi-core/log.h>
97
#include <avahi-common/simple-watch.h>
98
#include <avahi-common/malloc.h>
99
#include <avahi-common/error.h>
100
101
/* GnuTLS */
102
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
103
functions:
104
gnutls_*
105
init_gnutls_session(),
106
GNUTLS_* */
107
#include <gnutls/openpgp.h>
108
/* gnutls_certificate_set_openpgp_key_file(),
109
GNUTLS_OPENPGP_FMT_BASE64 */
110
111
/* GPGME */
112
#include <gpgme.h> /* All GPGME types, constants and
113
functions:
114
gpgme_*
115
GPGME_PROTOCOL_OpenPGP,
116
GPG_ERR_NO_* */
117
118
#define BUFFER_SIZE 256
119
120
#define PATHDIR "/conf/conf.d/mandos"
121
#define SECKEY "seckey.txt"
122
#define PUBKEY "pubkey.txt"
123
124
bool debug = false;
125
static const char mandos_protocol_version[] = "1";
126
const char *argp_program_version = "mandos-client " VERSION;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
128
129
/* Used for passing in values through the Avahi callback functions */
130
typedef struct {
131
AvahiSimplePoll *simple_poll;
132
AvahiServer *server;
133
gnutls_certificate_credentials_t cred;
134
unsigned int dh_bits;
135
gnutls_dh_params_t dh_params;
136
const char *priority;
137
gpgme_ctx_t ctx;
138
} mandos_context;
139
140
/* global context so signal handler can reach it*/
141
mandos_context mc = { .simple_poll = NULL, .server = NULL,
142
.dh_bits = 1024, .priority = "SECURE256"
143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
144
145
/*
146
* Make additional room in "buffer" for at least BUFFER_SIZE more
147
* bytes. "buffer_capacity" is how much is currently allocated,
148
* "buffer_length" is how much is already used.
149
*/
150
size_t incbuffer(char **buffer, size_t buffer_length,
151
size_t buffer_capacity){
152
if(buffer_length + BUFFER_SIZE > buffer_capacity){
153
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
154
if(buffer == NULL){
155
return 0;
156
}
157
buffer_capacity += BUFFER_SIZE;
158
}
159
return buffer_capacity;
160
}
161
162
/*
163
* Initialize GPGME.
164
*/
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
167
int ret;
168
gpgme_error_t rc;
169
gpgme_engine_info_t engine_info;
170
171
172
/*
173
* Helper function to insert pub and seckey to the engine keyring.
174
*/
175
bool import_key(const char *filename){
176
int fd;
177
gpgme_data_t pgp_data;
178
179
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
180
if(fd == -1){
181
perror("open");
182
return false;
183
}
184
185
rc = gpgme_data_new_from_fd(&pgp_data, fd);
186
if(rc != GPG_ERR_NO_ERROR){
187
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
189
return false;
190
}
191
192
rc = gpgme_op_import(mc.ctx, pgp_data);
193
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
196
return false;
197
}
198
199
ret = (int)TEMP_FAILURE_RETRY(close(fd));
200
if(ret == -1){
201
perror("close");
202
}
203
gpgme_data_release(pgp_data);
204
return true;
205
}
206
207
if(debug){
208
fprintf(stderr, "Initializing GPGME\n");
209
}
210
211
/* Init GPGME */
212
gpgme_check_version(NULL);
213
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
214
if(rc != GPG_ERR_NO_ERROR){
215
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
216
gpgme_strsource(rc), gpgme_strerror(rc));
217
return false;
218
}
219
220
/* Set GPGME home directory for the OpenPGP engine only */
221
rc = gpgme_get_engine_info(&engine_info);
222
if(rc != GPG_ERR_NO_ERROR){
223
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
225
return false;
226
}
227
while(engine_info != NULL){
228
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
229
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
230
engine_info->file_name, tempdir);
231
break;
232
}
233
engine_info = engine_info->next;
234
}
235
if(engine_info == NULL){
236
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
237
return false;
238
}
239
240
/* Create new GPGME "context" */
241
rc = gpgme_new(&(mc.ctx));
242
if(rc != GPG_ERR_NO_ERROR){
243
fprintf(stderr, "bad gpgme_new: %s: %s\n",
244
gpgme_strsource(rc), gpgme_strerror(rc));
245
return false;
246
}
247
248
if(not import_key(pubkey) or not import_key(seckey)){
249
return false;
250
}
251
252
return true;
253
}
254
255
/*
256
* Decrypt OpenPGP data.
257
* Returns -1 on error
258
*/
259
static ssize_t pgp_packet_decrypt(const char *cryptotext,
260
size_t crypto_size,
261
char **plaintext){
262
gpgme_data_t dh_crypto, dh_plain;
263
gpgme_error_t rc;
264
ssize_t ret;
265
size_t plaintext_capacity = 0;
266
ssize_t plaintext_length = 0;
267
268
if(debug){
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
270
}
271
272
/* Create new GPGME data buffer from memory cryptotext */
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
274
0);
275
if(rc != GPG_ERR_NO_ERROR){
276
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
278
return -1;
279
}
280
281
/* Create new empty GPGME data buffer for the plaintext */
282
rc = gpgme_data_new(&dh_plain);
283
if(rc != GPG_ERR_NO_ERROR){
284
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
286
gpgme_data_release(dh_crypto);
287
return -1;
288
}
289
290
/* Decrypt data from the cryptotext data buffer to the plaintext
291
data buffer */
292
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
293
if(rc != GPG_ERR_NO_ERROR){
294
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
295
gpgme_strsource(rc), gpgme_strerror(rc));
296
plaintext_length = -1;
297
if(debug){
298
gpgme_decrypt_result_t result;
299
result = gpgme_op_decrypt_result(mc.ctx);
300
if(result == NULL){
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
302
} else {
303
fprintf(stderr, "Unsupported algorithm: %s\n",
304
result->unsupported_algorithm);
305
fprintf(stderr, "Wrong key usage: %u\n",
306
result->wrong_key_usage);
307
if(result->file_name != NULL){
308
fprintf(stderr, "File name: %s\n", result->file_name);
309
}
310
gpgme_recipient_t recipient;
311
recipient = result->recipients;
312
while(recipient != NULL){
313
fprintf(stderr, "Public key algorithm: %s\n",
314
gpgme_pubkey_algo_name(recipient->pubkey_algo));
315
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
316
fprintf(stderr, "Secret key available: %s\n",
317
recipient->status == GPG_ERR_NO_SECKEY
318
? "No" : "Yes");
319
recipient = recipient->next;
320
}
321
}
322
}
323
goto decrypt_end;
324
}
325
326
if(debug){
327
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
328
}
329
330
/* Seek back to the beginning of the GPGME plaintext data buffer */
331
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
332
perror("gpgme_data_seek");
333
plaintext_length = -1;
334
goto decrypt_end;
335
}
336
337
*plaintext = NULL;
338
while(true){
339
plaintext_capacity = incbuffer(plaintext,
340
(size_t)plaintext_length,
341
plaintext_capacity);
342
if(plaintext_capacity == 0){
343
perror("incbuffer");
344
plaintext_length = -1;
345
goto decrypt_end;
346
}
347
348
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
349
BUFFER_SIZE);
350
/* Print the data, if any */
351
if(ret == 0){
352
/* EOF */
353
break;
354
}
355
if(ret < 0){
356
perror("gpgme_data_read");
357
plaintext_length = -1;
358
goto decrypt_end;
359
}
360
plaintext_length += ret;
361
}
362
363
if(debug){
364
fprintf(stderr, "Decrypted password is: ");
365
for(ssize_t i = 0; i < plaintext_length; i++){
366
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
367
}
368
fprintf(stderr, "\n");
369
}
370
371
decrypt_end:
372
373
/* Delete the GPGME cryptotext data buffer */
374
gpgme_data_release(dh_crypto);
375
376
/* Delete the GPGME plaintext data buffer */
377
gpgme_data_release(dh_plain);
378
return plaintext_length;
379
}
380
381
static const char * safer_gnutls_strerror(int value){
382
const char *ret = gnutls_strerror(value); /* Spurious warning from
383
-Wunreachable-code */
384
if(ret == NULL)
385
ret = "(unknown)";
386
return ret;
387
}
388
389
/* GnuTLS log function callback */
390
static void debuggnutls(__attribute__((unused)) int level,
391
const char* string){
392
fprintf(stderr, "GnuTLS: %s", string);
393
}
394
395
static int init_gnutls_global(const char *pubkeyfilename,
396
const char *seckeyfilename){
397
int ret;
398
399
if(debug){
400
fprintf(stderr, "Initializing GnuTLS\n");
401
}
402
403
ret = gnutls_global_init();
404
if(ret != GNUTLS_E_SUCCESS){
405
fprintf(stderr, "GnuTLS global_init: %s\n",
406
safer_gnutls_strerror(ret));
407
return -1;
408
}
409
410
if(debug){
411
/* "Use a log level over 10 to enable all debugging options."
412
* - GnuTLS manual
413
*/
414
gnutls_global_set_log_level(11);
415
gnutls_global_set_log_function(debuggnutls);
416
}
417
418
/* OpenPGP credentials */
419
gnutls_certificate_allocate_credentials(&mc.cred);
420
if(ret != GNUTLS_E_SUCCESS){
421
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
422
from
423
-Wunreachable-code
424
*/
425
safer_gnutls_strerror(ret));
426
gnutls_global_deinit();
427
return -1;
428
}
429
430
if(debug){
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
433
seckeyfilename);
434
}
435
436
ret = gnutls_certificate_set_openpgp_key_file
437
(mc.cred, pubkeyfilename, seckeyfilename,
438
GNUTLS_OPENPGP_FMT_BASE64);
439
if(ret != GNUTLS_E_SUCCESS){
440
fprintf(stderr,
441
"Error[%d] while reading the OpenPGP key pair ('%s',"
442
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
443
fprintf(stderr, "The GnuTLS error is: %s\n",
444
safer_gnutls_strerror(ret));
445
goto globalfail;
446
}
447
448
/* GnuTLS server initialization */
449
ret = gnutls_dh_params_init(&mc.dh_params);
450
if(ret != GNUTLS_E_SUCCESS){
451
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
452
" %s\n", safer_gnutls_strerror(ret));
453
goto globalfail;
454
}
455
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
456
if(ret != GNUTLS_E_SUCCESS){
457
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
458
safer_gnutls_strerror(ret));
459
goto globalfail;
460
}
461
462
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
463
464
return 0;
465
466
globalfail:
467
468
gnutls_certificate_free_credentials(mc.cred);
469
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
471
return -1;
472
}
473
474
static int init_gnutls_session(gnutls_session_t *session){
475
int ret;
476
/* GnuTLS session creation */
477
ret = gnutls_init(session, GNUTLS_SERVER);
478
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
480
safer_gnutls_strerror(ret));
481
}
482
483
{
484
const char *err;
485
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
486
if(ret != GNUTLS_E_SUCCESS){
487
fprintf(stderr, "Syntax error at: %s\n", err);
488
fprintf(stderr, "GnuTLS error: %s\n",
489
safer_gnutls_strerror(ret));
490
gnutls_deinit(*session);
491
return -1;
492
}
493
}
494
495
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
496
mc.cred);
497
if(ret != GNUTLS_E_SUCCESS){
498
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
499
safer_gnutls_strerror(ret));
500
gnutls_deinit(*session);
501
return -1;
502
}
503
504
/* ignore client certificate if any. */
505
gnutls_certificate_server_set_request(*session,
506
GNUTLS_CERT_IGNORE);
507
508
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
509
510
return 0;
511
}
512
513
/* Avahi log function callback */
514
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
515
__attribute__((unused)) const char *txt){}
516
517
/* Called when a Mandos server is found */
518
static int start_mandos_communication(const char *ip, uint16_t port,
519
AvahiIfIndex if_index,
520
int af){
521
int ret, tcp_sd;
522
ssize_t sret;
523
union {
524
struct sockaddr_in in;
525
struct sockaddr_in6 in6;
526
} to;
527
char *buffer = NULL;
528
char *decrypted_buffer;
529
size_t buffer_length = 0;
530
size_t buffer_capacity = 0;
531
ssize_t decrypted_buffer_size;
532
size_t written;
533
int retval = 0;
534
gnutls_session_t session;
535
int pf; /* Protocol family */
536
537
switch(af){
538
case AF_INET6:
539
pf = PF_INET6;
540
break;
541
case AF_INET:
542
pf = PF_INET;
543
break;
544
default:
545
fprintf(stderr, "Bad address family: %d\n", af);
546
return -1;
547
}
548
549
ret = init_gnutls_session(&session);
550
if(ret != 0){
551
return -1;
552
}
553
554
if(debug){
555
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
556
"\n", ip, port);
557
}
558
559
tcp_sd = socket(pf, SOCK_STREAM, 0);
560
if(tcp_sd < 0){
561
perror("socket");
562
return -1;
563
}
564
565
memset(&to, 0, sizeof(to));
566
if(af == AF_INET6){
567
to.in6.sin6_family = (sa_family_t)af;
568
ret = inet_pton(af, ip, &to.in6.sin6_addr);
569
} else { /* IPv4 */
570
to.in.sin_family = (sa_family_t)af;
571
ret = inet_pton(af, ip, &to.in.sin_addr);
572
}
573
if(ret < 0 ){
574
perror("inet_pton");
575
return -1;
576
}
577
if(ret == 0){
578
fprintf(stderr, "Bad address: %s\n", ip);
579
return -1;
580
}
581
if(af == AF_INET6){
582
to.in6.sin6_port = htons(port); /* Spurious warnings from
583
-Wconversion and
584
-Wunreachable-code */
585
586
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
587
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
588
-Wunreachable-code*/
589
if(if_index == AVAHI_IF_UNSPEC){
590
fprintf(stderr, "An IPv6 link-local address is incomplete"
591
" without a network interface\n");
592
return -1;
593
}
594
/* Set the network interface number as scope */
595
to.in6.sin6_scope_id = (uint32_t)if_index;
596
}
597
} else {
598
to.in.sin_port = htons(port); /* Spurious warnings from
599
-Wconversion and
600
-Wunreachable-code */
601
}
602
603
if(debug){
604
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
605
char interface[IF_NAMESIZE];
606
if(if_indextoname((unsigned int)if_index, interface) == NULL){
607
perror("if_indextoname");
608
} else {
609
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
610
ip, interface, port);
611
}
612
} else {
613
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
614
port);
615
}
616
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
617
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
618
const char *pcret;
619
if(af == AF_INET6){
620
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
621
sizeof(addrstr));
622
} else {
623
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
624
sizeof(addrstr));
625
}
626
if(pcret == NULL){
627
perror("inet_ntop");
628
} else {
629
if(strcmp(addrstr, ip) != 0){
630
fprintf(stderr, "Canonical address form: %s\n", addrstr);
631
}
632
}
633
}
634
635
if(af == AF_INET6){
636
ret = connect(tcp_sd, &to.in6, sizeof(to));
637
} else {
638
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
639
}
640
if(ret < 0){
641
perror("connect");
642
return -1;
643
}
644
645
const char *out = mandos_protocol_version;
646
written = 0;
647
while(true){
648
size_t out_size = strlen(out);
649
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
650
out_size - written));
651
if(ret == -1){
652
perror("write");
653
retval = -1;
654
goto mandos_end;
655
}
656
written += (size_t)ret;
657
if(written < out_size){
658
continue;
659
} else {
660
if(out == mandos_protocol_version){
661
written = 0;
662
out = "\r\n";
663
} else {
664
break;
665
}
666
}
667
}
668
669
if(debug){
670
fprintf(stderr, "Establishing TLS session with %s\n", ip);
671
}
672
673
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
674
675
do{
676
ret = gnutls_handshake(session);
677
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
678
679
if(ret != GNUTLS_E_SUCCESS){
680
if(debug){
681
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
682
gnutls_perror(ret);
683
}
684
retval = -1;
685
goto mandos_end;
686
}
687
688
/* Read OpenPGP packet that contains the wanted password */
689
690
if(debug){
691
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
692
ip);
693
}
694
695
while(true){
696
buffer_capacity = incbuffer(&buffer, buffer_length,
697
buffer_capacity);
698
if(buffer_capacity == 0){
699
perror("incbuffer");
700
retval = -1;
701
goto mandos_end;
702
}
703
704
sret = gnutls_record_recv(session, buffer+buffer_length,
705
BUFFER_SIZE);
706
if(sret == 0){
707
break;
708
}
709
if(sret < 0){
710
switch(sret){
711
case GNUTLS_E_INTERRUPTED:
712
case GNUTLS_E_AGAIN:
713
break;
714
case GNUTLS_E_REHANDSHAKE:
715
do{
716
ret = gnutls_handshake(session);
717
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
718
if(ret < 0){
719
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
720
gnutls_perror(ret);
721
retval = -1;
722
goto mandos_end;
723
}
724
break;
725
default:
726
fprintf(stderr, "Unknown error while reading data from"
727
" encrypted session with Mandos server\n");
728
retval = -1;
729
gnutls_bye(session, GNUTLS_SHUT_RDWR);
730
goto mandos_end;
731
}
732
} else {
733
buffer_length += (size_t) sret;
734
}
735
}
736
737
if(debug){
738
fprintf(stderr, "Closing TLS session\n");
739
}
740
741
gnutls_bye(session, GNUTLS_SHUT_RDWR);
742
743
if(buffer_length > 0){
744
decrypted_buffer_size = pgp_packet_decrypt(buffer,
745
buffer_length,
746
&decrypted_buffer);
747
if(decrypted_buffer_size >= 0){
748
written = 0;
749
while(written < (size_t) decrypted_buffer_size){
750
ret = (int)fwrite(decrypted_buffer + written, 1,
751
(size_t)decrypted_buffer_size - written,
752
stdout);
753
if(ret == 0 and ferror(stdout)){
754
if(debug){
755
fprintf(stderr, "Error writing encrypted data: %s\n",
756
strerror(errno));
757
}
758
retval = -1;
759
break;
760
}
761
written += (size_t)ret;
762
}
763
free(decrypted_buffer);
764
} else {
765
retval = -1;
766
}
767
} else {
768
retval = -1;
769
}
770
771
/* Shutdown procedure */
772
773
mandos_end:
774
free(buffer);
775
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
776
if(ret == -1){
777
perror("close");
778
}
779
gnutls_deinit(session);
780
return retval;
781
}
782
783
sig_atomic_t quit_now = 0;
784
785
static void resolve_callback(AvahiSServiceResolver *r,
786
AvahiIfIndex interface,
787
AvahiProtocol proto,
788
AvahiResolverEvent event,
789
const char *name,
790
const char *type,
791
const char *domain,
792
const char *host_name,
793
const AvahiAddress *address,
794
uint16_t port,
795
AVAHI_GCC_UNUSED AvahiStringList *txt,
796
AVAHI_GCC_UNUSED AvahiLookupResultFlags
797
flags,
798
AVAHI_GCC_UNUSED void* userdata){
799
assert(r);
800
801
/* Called whenever a service has been resolved successfully or
802
timed out */
803
804
if(quit_now){
805
return;
806
}
807
808
switch(event){
809
default:
810
case AVAHI_RESOLVER_FAILURE:
811
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
812
" of type '%s' in domain '%s': %s\n", name, type, domain,
813
avahi_strerror(avahi_server_errno(mc.server)));
814
break;
815
816
case AVAHI_RESOLVER_FOUND:
817
{
818
char ip[AVAHI_ADDRESS_STR_MAX];
819
avahi_address_snprint(ip, sizeof(ip), address);
820
if(debug){
821
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
822
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
823
ip, (intmax_t)interface, port);
824
}
825
int ret = start_mandos_communication(ip, port, interface,
826
avahi_proto_to_af(proto));
827
if(ret == 0){
828
avahi_simple_poll_quit(mc.simple_poll);
829
}
830
}
831
}
832
avahi_s_service_resolver_free(r);
833
}
834
835
static void browse_callback(AvahiSServiceBrowser *b,
836
AvahiIfIndex interface,
837
AvahiProtocol protocol,
838
AvahiBrowserEvent event,
839
const char *name,
840
const char *type,
841
const char *domain,
842
AVAHI_GCC_UNUSED AvahiLookupResultFlags
843
flags,
844
AVAHI_GCC_UNUSED void* userdata){
845
assert(b);
846
847
/* Called whenever a new services becomes available on the LAN or
848
is removed from the LAN */
849
850
switch(event){
851
default:
852
case AVAHI_BROWSER_FAILURE:
853
854
fprintf(stderr, "(Avahi browser) %s\n",
855
avahi_strerror(avahi_server_errno(mc.server)));
856
avahi_simple_poll_quit(mc.simple_poll);
857
return;
858
859
case AVAHI_BROWSER_NEW:
860
/* We ignore the returned Avahi resolver object. In the callback
861
function we free it. If the Avahi server is terminated before
862
the callback function is called the Avahi server will free the
863
resolver for us. */
864
865
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
866
name, type, domain, protocol, 0,
867
resolve_callback, NULL) == NULL)
868
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
869
name, avahi_strerror(avahi_server_errno(mc.server)));
870
break;
871
872
case AVAHI_BROWSER_REMOVE:
873
break;
874
875
case AVAHI_BROWSER_ALL_FOR_NOW:
876
case AVAHI_BROWSER_CACHE_EXHAUSTED:
877
if(debug){
878
fprintf(stderr, "No Mandos server found, still searching...\n");
879
}
880
break;
881
}
882
}
883
884
/* stop main loop after sigterm has been called */
885
static void handle_sigterm(__attribute__((unused)) int sig){
886
if(quit_now){
887
return;
888
}
889
quit_now = 1;
890
int old_errno = errno;
891
if(mc.simple_poll != NULL){
892
avahi_simple_poll_quit(mc.simple_poll);
893
}
894
errno = old_errno;
895
}
896
897
int main(int argc, char *argv[]){
898
AvahiSServiceBrowser *sb = NULL;
899
int error;
900
int ret;
901
intmax_t tmpmax;
902
char *tmp;
903
int exitcode = EXIT_SUCCESS;
904
const char *interface = "eth0";
905
struct ifreq network;
906
int sd = -1;
907
bool take_down_interface = false;
908
uid_t uid;
909
gid_t gid;
910
char *connect_to = NULL;
911
char tempdir[] = "/tmp/mandosXXXXXX";
912
bool tempdir_created = false;
913
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
914
const char *seckey = PATHDIR "/" SECKEY;
915
const char *pubkey = PATHDIR "/" PUBKEY;
916
917
bool gnutls_initialized = false;
918
bool gpgme_initialized = false;
919
float delay = 2.5f;
920
921
struct sigaction old_sigterm_action;
922
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
923
924
{
925
struct argp_option options[] = {
926
{ .name = "debug", .key = 128,
927
.doc = "Debug mode", .group = 3 },
928
{ .name = "connect", .key = 'c',
929
.arg = "ADDRESS:PORT",
930
.doc = "Connect directly to a specific Mandos server",
931
.group = 1 },
932
{ .name = "interface", .key = 'i',
933
.arg = "NAME",
934
.doc = "Network interface that will be used to search for"
935
" Mandos servers",
936
.group = 1 },
937
{ .name = "seckey", .key = 's',
938
.arg = "FILE",
939
.doc = "OpenPGP secret key file base name",
940
.group = 1 },
941
{ .name = "pubkey", .key = 'p',
942
.arg = "FILE",
943
.doc = "OpenPGP public key file base name",
944
.group = 2 },
945
{ .name = "dh-bits", .key = 129,
946
.arg = "BITS",
947
.doc = "Bit length of the prime number used in the"
948
" Diffie-Hellman key exchange",
949
.group = 2 },
950
{ .name = "priority", .key = 130,
951
.arg = "STRING",
952
.doc = "GnuTLS priority string for the TLS handshake",
953
.group = 1 },
954
{ .name = "delay", .key = 131,
955
.arg = "SECONDS",
956
.doc = "Maximum delay to wait for interface startup",
957
.group = 2 },
958
{ .name = NULL }
959
};
960
961
error_t parse_opt(int key, char *arg,
962
struct argp_state *state){
963
switch(key){
964
case 128: /* --debug */
965
debug = true;
966
break;
967
case 'c': /* --connect */
968
connect_to = arg;
969
break;
970
case 'i': /* --interface */
971
interface = arg;
972
break;
973
case 's': /* --seckey */
974
seckey = arg;
975
break;
976
case 'p': /* --pubkey */
977
pubkey = arg;
978
break;
979
case 129: /* --dh-bits */
980
errno = 0;
981
tmpmax = strtoimax(arg, &tmp, 10);
982
if(errno != 0 or tmp == arg or *tmp != '\0'
983
or tmpmax != (typeof(mc.dh_bits))tmpmax){
984
fprintf(stderr, "Bad number of DH bits\n");
985
exit(EXIT_FAILURE);
986
}
987
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
988
break;
989
case 130: /* --priority */
990
mc.priority = arg;
991
break;
992
case 131: /* --delay */
993
errno = 0;
994
delay = strtof(arg, &tmp);
995
if(errno != 0 or tmp == arg or *tmp != '\0'){
996
fprintf(stderr, "Bad delay\n");
997
exit(EXIT_FAILURE);
998
}
999
break;
1000
case ARGP_KEY_ARG:
1001
argp_usage(state);
1002
case ARGP_KEY_END:
1003
break;
1004
default:
1005
return ARGP_ERR_UNKNOWN;
1006
}
1007
return 0;
1008
}
1009
1010
struct argp argp = { .options = options, .parser = parse_opt,
1011
.args_doc = "",
1012
.doc = "Mandos client -- Get and decrypt"
1013
" passwords from a Mandos server" };
1014
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1015
if(ret == ARGP_ERR_UNKNOWN){
1016
fprintf(stderr, "Unknown error while parsing arguments\n");
1017
exitcode = EXIT_FAILURE;
1018
goto end;
1019
}
1020
}
1021
1022
if(not debug){
1023
avahi_set_log_function(empty_log);
1024
}
1025
1026
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1027
from the signal handler */
1028
/* Initialize the pseudo-RNG for Avahi */
1029
srand((unsigned int) time(NULL));
1030
mc.simple_poll = avahi_simple_poll_new();
1031
if(mc.simple_poll == NULL){
1032
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1033
exitcode = EXIT_FAILURE;
1034
goto end;
1035
}
1036
1037
sigemptyset(&sigterm_action.sa_mask);
1038
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1039
if(ret == -1){
1040
perror("sigaddset");
1041
exitcode = EXIT_FAILURE;
1042
goto end;
1043
}
1044
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1045
if(ret == -1){
1046
perror("sigaddset");
1047
exitcode = EXIT_FAILURE;
1048
goto end;
1049
}
1050
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1051
if(ret == -1){
1052
perror("sigaddset");
1053
exitcode = EXIT_FAILURE;
1054
goto end;
1055
}
1056
ret = sigaction(SIGTERM, &sigterm_action, &old_sigterm_action);
1057
if(ret == -1){
1058
perror("sigaction");
1059
exitcode = EXIT_FAILURE;
1060
goto end;
1061
}
1062
1063
/* If the interface is down, bring it up */
1064
if(interface[0] != '\0'){
1065
if_index = (AvahiIfIndex) if_nametoindex(interface);
1066
if(if_index == 0){
1067
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1068
exitcode = EXIT_FAILURE;
1069
goto end;
1070
}
1071
1072
if(quit_now){
1073
goto end;
1074
}
1075
1076
#ifdef __linux__
1077
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1078
messages to mess up the prompt */
1079
ret = klogctl(8, NULL, 5);
1080
bool restore_loglevel = true;
1081
if(ret == -1){
1082
restore_loglevel = false;
1083
perror("klogctl");
1084
}
1085
#endif /* __linux__ */
1086
1087
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1088
if(sd < 0){
1089
perror("socket");
1090
exitcode = EXIT_FAILURE;
1091
#ifdef __linux__
1092
if(restore_loglevel){
1093
ret = klogctl(7, NULL, 0);
1094
if(ret == -1){
1095
perror("klogctl");
1096
}
1097
}
1098
#endif /* __linux__ */
1099
goto end;
1100
}
1101
strcpy(network.ifr_name, interface);
1102
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1103
if(ret == -1){
1104
perror("ioctl SIOCGIFFLAGS");
1105
#ifdef __linux__
1106
if(restore_loglevel){
1107
ret = klogctl(7, NULL, 0);
1108
if(ret == -1){
1109
perror("klogctl");
1110
}
1111
}
1112
#endif /* __linux__ */
1113
exitcode = EXIT_FAILURE;
1114
goto end;
1115
}
1116
if((network.ifr_flags & IFF_UP) == 0){
1117
network.ifr_flags |= IFF_UP;
1118
take_down_interface = true;
1119
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1120
if(ret == -1){
1121
take_down_interface = false;
1122
perror("ioctl SIOCSIFFLAGS");
1123
exitcode = EXIT_FAILURE;
1124
#ifdef __linux__
1125
if(restore_loglevel){
1126
ret = klogctl(7, NULL, 0);
1127
if(ret == -1){
1128
perror("klogctl");
1129
}
1130
}
1131
#endif /* __linux__ */
1132
goto end;
1133
}
1134
}
1135
/* sleep checking until interface is running */
1136
for(int i=0; i < delay * 4; i++){
1137
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1138
if(ret == -1){
1139
perror("ioctl SIOCGIFFLAGS");
1140
} else if(network.ifr_flags & IFF_RUNNING){
1141
break;
1142
}
1143
struct timespec sleeptime = { .tv_nsec = 250000000 };
1144
ret = nanosleep(&sleeptime, NULL);
1145
if(ret == -1 and errno != EINTR){
1146
perror("nanosleep");
1147
}
1148
}
1149
if(not take_down_interface){
1150
/* We won't need the socket anymore */
1151
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1152
if(ret == -1){
1153
perror("close");
1154
}
1155
}
1156
#ifdef __linux__
1157
if(restore_loglevel){
1158
/* Restores kernel loglevel to default */
1159
ret = klogctl(7, NULL, 0);
1160
if(ret == -1){
1161
perror("klogctl");
1162
}
1163
}
1164
#endif /* __linux__ */
1165
}
1166
1167
if(quit_now){
1168
goto end;
1169
}
1170
1171
uid = getuid();
1172
gid = getgid();
1173
1174
errno = 0;
1175
setgid(gid);
1176
if(ret == -1){
1177
perror("setgid");
1178
}
1179
1180
ret = setuid(uid);
1181
if(ret == -1){
1182
perror("setuid");
1183
}
1184
1185
if(quit_now){
1186
goto end;
1187
}
1188
1189
ret = init_gnutls_global(pubkey, seckey);
1190
if(ret == -1){
1191
fprintf(stderr, "init_gnutls_global failed\n");
1192
exitcode = EXIT_FAILURE;
1193
goto end;
1194
} else {
1195
gnutls_initialized = true;
1196
}
1197
1198
if(quit_now){
1199
goto end;
1200
}
1201
1202
tempdir_created = true;
1203
if(mkdtemp(tempdir) == NULL){
1204
tempdir_created = false;
1205
perror("mkdtemp");
1206
goto end;
1207
}
1208
1209
if(quit_now){
1210
goto end;
1211
}
1212
1213
if(not init_gpgme(pubkey, seckey, tempdir)){
1214
fprintf(stderr, "init_gpgme failed\n");
1215
exitcode = EXIT_FAILURE;
1216
goto end;
1217
} else {
1218
gpgme_initialized = true;
1219
}
1220
1221
if(quit_now){
1222
goto end;
1223
}
1224
1225
if(connect_to != NULL){
1226
/* Connect directly, do not use Zeroconf */
1227
/* (Mainly meant for debugging) */
1228
char *address = strrchr(connect_to, ':');
1229
if(address == NULL){
1230
fprintf(stderr, "No colon in address\n");
1231
exitcode = EXIT_FAILURE;
1232
goto end;
1233
}
1234
1235
if(quit_now){
1236
goto end;
1237
}
1238
1239
uint16_t port;
1240
errno = 0;
1241
tmpmax = strtoimax(address+1, &tmp, 10);
1242
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1243
or tmpmax != (uint16_t)tmpmax){
1244
fprintf(stderr, "Bad port number\n");
1245
exitcode = EXIT_FAILURE;
1246
goto end;
1247
}
1248
1249
if(quit_now){
1250
goto end;
1251
}
1252
1253
port = (uint16_t)tmpmax;
1254
*address = '\0';
1255
address = connect_to;
1256
/* Colon in address indicates IPv6 */
1257
int af;
1258
if(strchr(address, ':') != NULL){
1259
af = AF_INET6;
1260
} else {
1261
af = AF_INET;
1262
}
1263
1264
if(quit_now){
1265
goto end;
1266
}
1267
1268
ret = start_mandos_communication(address, port, if_index, af);
1269
if(ret < 0){
1270
exitcode = EXIT_FAILURE;
1271
} else {
1272
exitcode = EXIT_SUCCESS;
1273
}
1274
goto end;
1275
}
1276
1277
if(quit_now){
1278
goto end;
1279
}
1280
1281
{
1282
AvahiServerConfig config;
1283
/* Do not publish any local Zeroconf records */
1284
avahi_server_config_init(&config);
1285
config.publish_hinfo = 0;
1286
config.publish_addresses = 0;
1287
config.publish_workstation = 0;
1288
config.publish_domain = 0;
1289
1290
/* Allocate a new server */
1291
mc.server = avahi_server_new(avahi_simple_poll_get
1292
(mc.simple_poll), &config, NULL,
1293
NULL, &error);
1294
1295
/* Free the Avahi configuration data */
1296
avahi_server_config_free(&config);
1297
}
1298
1299
/* Check if creating the Avahi server object succeeded */
1300
if(mc.server == NULL){
1301
fprintf(stderr, "Failed to create Avahi server: %s\n",
1302
avahi_strerror(error));
1303
exitcode = EXIT_FAILURE;
1304
goto end;
1305
}
1306
1307
if(quit_now){
1308
goto end;
1309
}
1310
1311
/* Create the Avahi service browser */
1312
sb = avahi_s_service_browser_new(mc.server, if_index,
1313
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1314
NULL, 0, browse_callback, NULL);
1315
if(sb == NULL){
1316
fprintf(stderr, "Failed to create service browser: %s\n",
1317
avahi_strerror(avahi_server_errno(mc.server)));
1318
exitcode = EXIT_FAILURE;
1319
goto end;
1320
}
1321
1322
if(quit_now){
1323
goto end;
1324
}
1325
1326
/* Run the main loop */
1327
1328
if(debug){
1329
fprintf(stderr, "Starting Avahi loop search\n");
1330
}
1331
1332
avahi_simple_poll_loop(mc.simple_poll);
1333
1334
end:
1335
1336
if(debug){
1337
fprintf(stderr, "%s exiting\n", argv[0]);
1338
}
1339
1340
/* Cleanup things */
1341
if(sb != NULL)
1342
avahi_s_service_browser_free(sb);
1343
1344
if(mc.server != NULL)
1345
avahi_server_free(mc.server);
1346
1347
if(mc.simple_poll != NULL)
1348
avahi_simple_poll_free(mc.simple_poll);
1349
1350
if(gnutls_initialized){
1351
gnutls_certificate_free_credentials(mc.cred);
1352
gnutls_global_deinit();
1353
gnutls_dh_params_deinit(mc.dh_params);
1354
}
1355
1356
if(gpgme_initialized){
1357
gpgme_release(mc.ctx);
1358
}
1359
1360
/* Take down the network interface */
1361
if(take_down_interface){
1362
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1363
if(ret == -1){
1364
perror("ioctl SIOCGIFFLAGS");
1365
} else if(network.ifr_flags & IFF_UP) {
1366
network.ifr_flags &= ~IFF_UP; /* clear flag */
1367
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1368
if(ret == -1){
1369
perror("ioctl SIOCSIFFLAGS");
1370
}
1371
}
1372
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1373
if(ret == -1){
1374
perror("close");
1375
}
1376
}
1377
1378
/* Removes the temp directory used by GPGME */
1379
if(tempdir_created){
1380
DIR *d;
1381
struct dirent *direntry;
1382
d = opendir(tempdir);
1383
if(d == NULL){
1384
if(errno != ENOENT){
1385
perror("opendir");
1386
}
1387
} else {
1388
while(true){
1389
direntry = readdir(d);
1390
if(direntry == NULL){
1391
break;
1392
}
1393
/* Skip "." and ".." */
1394
if(direntry->d_name[0] == '.'
1395
and (direntry->d_name[1] == '\0'
1396
or (direntry->d_name[1] == '.'
1397
and direntry->d_name[2] == '\0'))){
1398
continue;
1399
}
1400
char *fullname = NULL;
1401
ret = asprintf(&fullname, "%s/%s", tempdir,
1402
direntry->d_name);
1403
if(ret < 0){
1404
perror("asprintf");
1405
continue;
1406
}
1407
ret = remove(fullname);
1408
if(ret == -1){
1409
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1410
strerror(errno));
1411
}
1412
free(fullname);
1413
}
1414
closedir(d);
1415
}
1416
ret = rmdir(tempdir);
1417
if(ret == -1 and errno != ENOENT){
1418
perror("rmdir");
1419
}
1420
}
1421
1422
return exitcode;
1423
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0