1
/* -*- coding: utf-8 -*- */
3
* Mandos-client - get and decrypt data from a Mandos server
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".
12
* Copyright © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
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.
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.
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/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
37
#define _FILE_OFFSET_BITS 64
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
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,
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(),
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()
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
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
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), setuid(),
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, sig_atomic_t,
87
#include <sys/klog.h> /* klogctl() */
88
#endif /* __linux__ */
91
/* All Avahi types, constants and functions
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>
102
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
105
init_gnutls_session(),
107
#include <gnutls/openpgp.h>
108
/* gnutls_certificate_set_openpgp_key_file(),
109
GNUTLS_OPENPGP_FMT_BASE64 */
112
#include <gpgme.h> /* All GPGME types, constants and
115
GPGME_PROTOCOL_OpenPGP,
118
#define BUFFER_SIZE 256
120
#define PATHDIR "/conf/conf.d/mandos"
121
#define SECKEY "seckey.txt"
122
#define PUBKEY "pubkey.txt"
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>";
129
/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
133
gnutls_certificate_credentials_t cred;
134
unsigned int dh_bits;
135
gnutls_dh_params_t dh_params;
136
const char *priority;
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" };
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.
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);
157
buffer_capacity += BUFFER_SIZE;
159
return buffer_capacity;
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
169
gpgme_engine_info_t engine_info;
173
* Helper function to insert pub and seckey to the engine keyring.
175
bool import_key(const char *filename){
177
gpgme_data_t pgp_data;
179
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
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));
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));
199
ret = (int)TEMP_FAILURE_RETRY(close(fd));
203
gpgme_data_release(pgp_data);
208
fprintf(stderr, "Initializing GPGME\n");
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));
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));
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);
233
engine_info = engine_info->next;
235
if(engine_info == NULL){
236
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
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));
248
if(not import_key(pubkey) or not import_key(seckey)){
256
* Decrypt OpenPGP data.
257
* Returns -1 on error
259
static ssize_t pgp_packet_decrypt(const char *cryptotext,
262
gpgme_data_t dh_crypto, dh_plain;
265
size_t plaintext_capacity = 0;
266
ssize_t plaintext_length = 0;
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
272
/* Create new GPGME data buffer from memory cryptotext */
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
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));
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);
290
/* Decrypt data from the cryptotext data buffer to the plaintext
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;
298
gpgme_decrypt_result_t result;
299
result = gpgme_op_decrypt_result(mc.ctx);
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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);
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
319
recipient = recipient->next;
327
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
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;
339
plaintext_capacity = incbuffer(plaintext,
340
(size_t)plaintext_length,
342
if(plaintext_capacity == 0){
344
plaintext_length = -1;
348
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
350
/* Print the data, if any */
356
perror("gpgme_data_read");
357
plaintext_length = -1;
360
plaintext_length += ret;
364
fprintf(stderr, "Decrypted password is: ");
365
for(ssize_t i = 0; i < plaintext_length; i++){
366
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
368
fprintf(stderr, "\n");
373
/* Delete the GPGME cryptotext data buffer */
374
gpgme_data_release(dh_crypto);
376
/* Delete the GPGME plaintext data buffer */
377
gpgme_data_release(dh_plain);
378
return plaintext_length;
381
static const char * safer_gnutls_strerror(int value){
382
const char *ret = gnutls_strerror(value); /* Spurious warning from
383
-Wunreachable-code */
389
/* GnuTLS log function callback */
390
static void debuggnutls(__attribute__((unused)) int level,
392
fprintf(stderr, "GnuTLS: %s", string);
395
static int init_gnutls_global(const char *pubkeyfilename,
396
const char *seckeyfilename){
400
fprintf(stderr, "Initializing GnuTLS\n");
403
ret = gnutls_global_init();
404
if(ret != GNUTLS_E_SUCCESS){
405
fprintf(stderr, "GnuTLS global_init: %s\n",
406
safer_gnutls_strerror(ret));
411
/* "Use a log level over 10 to enable all debugging options."
414
gnutls_global_set_log_level(11);
415
gnutls_global_set_log_function(debuggnutls);
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
425
safer_gnutls_strerror(ret));
426
gnutls_global_deinit();
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
436
ret = gnutls_certificate_set_openpgp_key_file
437
(mc.cred, pubkeyfilename, seckeyfilename,
438
GNUTLS_OPENPGP_FMT_BASE64);
439
if(ret != GNUTLS_E_SUCCESS){
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));
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));
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));
462
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
468
gnutls_certificate_free_credentials(mc.cred);
469
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
474
static int init_gnutls_session(gnutls_session_t *session){
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));
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);
495
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
497
if(ret != GNUTLS_E_SUCCESS){
498
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
499
safer_gnutls_strerror(ret));
500
gnutls_deinit(*session);
504
/* ignore client certificate if any. */
505
gnutls_certificate_server_set_request(*session,
508
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
513
/* Avahi log function callback */
514
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
515
__attribute__((unused)) const char *txt){}
517
sig_atomic_t quit_now = 0;
518
int signal_received = 0;
520
/* Called when a Mandos server is found */
521
static int start_mandos_communication(const char *ip, uint16_t port,
522
AvahiIfIndex if_index,
527
struct sockaddr_in in;
528
struct sockaddr_in6 in6;
531
char *decrypted_buffer;
532
size_t buffer_length = 0;
533
size_t buffer_capacity = 0;
534
ssize_t decrypted_buffer_size;
537
gnutls_session_t session;
538
int pf; /* Protocol family */
548
fprintf(stderr, "Bad address family: %d\n", af);
552
ret = init_gnutls_session(&session);
558
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
562
tcp_sd = socket(pf, SOCK_STREAM, 0);
568
memset(&to, 0, sizeof(to));
570
to.in6.sin6_family = (sa_family_t)af;
571
ret = inet_pton(af, ip, &to.in6.sin6_addr);
573
to.in.sin_family = (sa_family_t)af;
574
ret = inet_pton(af, ip, &to.in.sin_addr);
581
fprintf(stderr, "Bad address: %s\n", ip);
585
to.in6.sin6_port = htons(port); /* Spurious warnings from
587
-Wunreachable-code */
589
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
590
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
592
if(if_index == AVAHI_IF_UNSPEC){
593
fprintf(stderr, "An IPv6 link-local address is incomplete"
594
" without a network interface\n");
597
/* Set the network interface number as scope */
598
to.in6.sin6_scope_id = (uint32_t)if_index;
601
to.in.sin_port = htons(port); /* Spurious warnings from
603
-Wunreachable-code */
607
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
608
char interface[IF_NAMESIZE];
609
if(if_indextoname((unsigned int)if_index, interface) == NULL){
610
perror("if_indextoname");
612
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
613
ip, interface, port);
616
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
619
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
620
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
623
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
626
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
632
if(strcmp(addrstr, ip) != 0){
633
fprintf(stderr, "Canonical address form: %s\n", addrstr);
639
ret = connect(tcp_sd, &to.in6, sizeof(to));
641
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
648
const char *out = mandos_protocol_version;
651
size_t out_size = strlen(out);
652
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
653
out_size - written));
659
written += (size_t)ret;
660
if(written < out_size){
663
if(out == mandos_protocol_version){
673
fprintf(stderr, "Establishing TLS session with %s\n", ip);
676
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
679
ret = gnutls_handshake(session);
680
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
682
if(ret != GNUTLS_E_SUCCESS){
684
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
691
/* Read OpenPGP packet that contains the wanted password */
694
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
699
buffer_capacity = incbuffer(&buffer, buffer_length,
701
if(buffer_capacity == 0){
707
sret = gnutls_record_recv(session, buffer+buffer_length,
714
case GNUTLS_E_INTERRUPTED:
717
case GNUTLS_E_REHANDSHAKE:
719
ret = gnutls_handshake(session);
720
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
722
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
729
fprintf(stderr, "Unknown error while reading data from"
730
" encrypted session with Mandos server\n");
732
gnutls_bye(session, GNUTLS_SHUT_RDWR);
736
buffer_length += (size_t) sret;
741
fprintf(stderr, "Closing TLS session\n");
744
gnutls_bye(session, GNUTLS_SHUT_RDWR);
746
if(buffer_length > 0){
747
decrypted_buffer_size = pgp_packet_decrypt(buffer,
750
if(decrypted_buffer_size >= 0){
752
while(written < (size_t) decrypted_buffer_size){
753
ret = (int)fwrite(decrypted_buffer + written, 1,
754
(size_t)decrypted_buffer_size - written,
756
if(ret == 0 and ferror(stdout)){
758
fprintf(stderr, "Error writing encrypted data: %s\n",
764
written += (size_t)ret;
766
free(decrypted_buffer);
774
/* Shutdown procedure */
778
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
782
gnutls_deinit(session);
786
static void resolve_callback(AvahiSServiceResolver *r,
787
AvahiIfIndex interface,
789
AvahiResolverEvent event,
793
const char *host_name,
794
const AvahiAddress *address,
796
AVAHI_GCC_UNUSED AvahiStringList *txt,
797
AVAHI_GCC_UNUSED AvahiLookupResultFlags
799
AVAHI_GCC_UNUSED void* userdata){
802
/* Called whenever a service has been resolved successfully or
811
case AVAHI_RESOLVER_FAILURE:
812
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
813
" of type '%s' in domain '%s': %s\n", name, type, domain,
814
avahi_strerror(avahi_server_errno(mc.server)));
817
case AVAHI_RESOLVER_FOUND:
819
char ip[AVAHI_ADDRESS_STR_MAX];
820
avahi_address_snprint(ip, sizeof(ip), address);
822
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
823
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
824
ip, (intmax_t)interface, port);
826
int ret = start_mandos_communication(ip, port, interface,
827
avahi_proto_to_af(proto));
829
avahi_simple_poll_quit(mc.simple_poll);
833
avahi_s_service_resolver_free(r);
836
static void browse_callback(AvahiSServiceBrowser *b,
837
AvahiIfIndex interface,
838
AvahiProtocol protocol,
839
AvahiBrowserEvent event,
843
AVAHI_GCC_UNUSED AvahiLookupResultFlags
845
AVAHI_GCC_UNUSED void* userdata){
848
/* Called whenever a new services becomes available on the LAN or
849
is removed from the LAN */
853
case AVAHI_BROWSER_FAILURE:
855
fprintf(stderr, "(Avahi browser) %s\n",
856
avahi_strerror(avahi_server_errno(mc.server)));
857
avahi_simple_poll_quit(mc.simple_poll);
860
case AVAHI_BROWSER_NEW:
861
/* We ignore the returned Avahi resolver object. In the callback
862
function we free it. If the Avahi server is terminated before
863
the callback function is called the Avahi server will free the
866
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
867
name, type, domain, protocol, 0,
868
resolve_callback, NULL) == NULL)
869
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
870
name, avahi_strerror(avahi_server_errno(mc.server)));
873
case AVAHI_BROWSER_REMOVE:
876
case AVAHI_BROWSER_ALL_FOR_NOW:
877
case AVAHI_BROWSER_CACHE_EXHAUSTED:
879
fprintf(stderr, "No Mandos server found, still searching...\n");
885
/* stop main loop after sigterm has been called */
886
static void handle_sigterm(int sig){
891
signal_received = sig;
892
int old_errno = errno;
893
if(mc.simple_poll != NULL){
894
avahi_simple_poll_quit(mc.simple_poll);
899
int main(int argc, char *argv[]){
900
AvahiSServiceBrowser *sb = NULL;
905
int exitcode = EXIT_SUCCESS;
906
const char *interface = "eth0";
907
struct ifreq network;
909
bool take_down_interface = false;
912
char *connect_to = NULL;
913
char tempdir[] = "/tmp/mandosXXXXXX";
914
bool tempdir_created = false;
915
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
916
const char *seckey = PATHDIR "/" SECKEY;
917
const char *pubkey = PATHDIR "/" PUBKEY;
919
bool gnutls_initialized = false;
920
bool gpgme_initialized = false;
923
struct sigaction old_sigterm_action;
924
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
927
struct argp_option options[] = {
928
{ .name = "debug", .key = 128,
929
.doc = "Debug mode", .group = 3 },
930
{ .name = "connect", .key = 'c',
931
.arg = "ADDRESS:PORT",
932
.doc = "Connect directly to a specific Mandos server",
934
{ .name = "interface", .key = 'i',
936
.doc = "Network interface that will be used to search for"
939
{ .name = "seckey", .key = 's',
941
.doc = "OpenPGP secret key file base name",
943
{ .name = "pubkey", .key = 'p',
945
.doc = "OpenPGP public key file base name",
947
{ .name = "dh-bits", .key = 129,
949
.doc = "Bit length of the prime number used in the"
950
" Diffie-Hellman key exchange",
952
{ .name = "priority", .key = 130,
954
.doc = "GnuTLS priority string for the TLS handshake",
956
{ .name = "delay", .key = 131,
958
.doc = "Maximum delay to wait for interface startup",
963
error_t parse_opt(int key, char *arg,
964
struct argp_state *state){
966
case 128: /* --debug */
969
case 'c': /* --connect */
972
case 'i': /* --interface */
975
case 's': /* --seckey */
978
case 'p': /* --pubkey */
981
case 129: /* --dh-bits */
983
tmpmax = strtoimax(arg, &tmp, 10);
984
if(errno != 0 or tmp == arg or *tmp != '\0'
985
or tmpmax != (typeof(mc.dh_bits))tmpmax){
986
fprintf(stderr, "Bad number of DH bits\n");
989
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
991
case 130: /* --priority */
994
case 131: /* --delay */
996
delay = strtof(arg, &tmp);
997
if(errno != 0 or tmp == arg or *tmp != '\0'){
998
fprintf(stderr, "Bad delay\n");
1007
return ARGP_ERR_UNKNOWN;
1012
struct argp argp = { .options = options, .parser = parse_opt,
1014
.doc = "Mandos client -- Get and decrypt"
1015
" passwords from a Mandos server" };
1016
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1017
if(ret == ARGP_ERR_UNKNOWN){
1018
fprintf(stderr, "Unknown error while parsing arguments\n");
1019
exitcode = EXIT_FAILURE;
1025
avahi_set_log_function(empty_log);
1028
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1029
from the signal handler */
1030
/* Initialize the pseudo-RNG for Avahi */
1031
srand((unsigned int) time(NULL));
1032
mc.simple_poll = avahi_simple_poll_new();
1033
if(mc.simple_poll == NULL){
1034
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1035
exitcode = EXIT_FAILURE;
1039
sigemptyset(&sigterm_action.sa_mask);
1040
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1042
perror("sigaddset");
1043
exitcode = EXIT_FAILURE;
1046
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1048
perror("sigaddset");
1049
exitcode = EXIT_FAILURE;
1052
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1054
perror("sigaddset");
1055
exitcode = EXIT_FAILURE;
1058
ret = sigaction(SIGINT, &sigterm_action, &old_sigterm_action);
1060
perror("sigaction");
1061
exitcode = EXIT_FAILURE;
1064
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1066
perror("sigaction");
1067
exitcode = EXIT_FAILURE;
1070
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1072
perror("sigaction");
1073
exitcode = EXIT_FAILURE;
1077
/* If the interface is down, bring it up */
1078
if(interface[0] != '\0'){
1079
if_index = (AvahiIfIndex) if_nametoindex(interface);
1081
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1082
exitcode = EXIT_FAILURE;
1091
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1092
messages to mess up the prompt */
1093
ret = klogctl(8, NULL, 5);
1094
bool restore_loglevel = true;
1096
restore_loglevel = false;
1099
#endif /* __linux__ */
1101
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1104
exitcode = EXIT_FAILURE;
1106
if(restore_loglevel){
1107
ret = klogctl(7, NULL, 0);
1112
#endif /* __linux__ */
1115
strcpy(network.ifr_name, interface);
1116
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1118
perror("ioctl SIOCGIFFLAGS");
1120
if(restore_loglevel){
1121
ret = klogctl(7, NULL, 0);
1126
#endif /* __linux__ */
1127
exitcode = EXIT_FAILURE;
1130
if((network.ifr_flags & IFF_UP) == 0){
1131
network.ifr_flags |= IFF_UP;
1132
take_down_interface = true;
1133
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1135
take_down_interface = false;
1136
perror("ioctl SIOCSIFFLAGS");
1137
exitcode = EXIT_FAILURE;
1139
if(restore_loglevel){
1140
ret = klogctl(7, NULL, 0);
1145
#endif /* __linux__ */
1149
/* sleep checking until interface is running */
1150
for(int i=0; i < delay * 4; i++){
1151
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1153
perror("ioctl SIOCGIFFLAGS");
1154
} else if(network.ifr_flags & IFF_RUNNING){
1157
struct timespec sleeptime = { .tv_nsec = 250000000 };
1158
ret = nanosleep(&sleeptime, NULL);
1159
if(ret == -1 and errno != EINTR){
1160
perror("nanosleep");
1163
if(not take_down_interface){
1164
/* We won't need the socket anymore */
1165
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1171
if(restore_loglevel){
1172
/* Restores kernel loglevel to default */
1173
ret = klogctl(7, NULL, 0);
1178
#endif /* __linux__ */
1203
ret = init_gnutls_global(pubkey, seckey);
1205
fprintf(stderr, "init_gnutls_global failed\n");
1206
exitcode = EXIT_FAILURE;
1209
gnutls_initialized = true;
1216
tempdir_created = true;
1217
if(mkdtemp(tempdir) == NULL){
1218
tempdir_created = false;
1227
if(not init_gpgme(pubkey, seckey, tempdir)){
1228
fprintf(stderr, "init_gpgme failed\n");
1229
exitcode = EXIT_FAILURE;
1232
gpgme_initialized = true;
1239
if(connect_to != NULL){
1240
/* Connect directly, do not use Zeroconf */
1241
/* (Mainly meant for debugging) */
1242
char *address = strrchr(connect_to, ':');
1243
if(address == NULL){
1244
fprintf(stderr, "No colon in address\n");
1245
exitcode = EXIT_FAILURE;
1255
tmpmax = strtoimax(address+1, &tmp, 10);
1256
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1257
or tmpmax != (uint16_t)tmpmax){
1258
fprintf(stderr, "Bad port number\n");
1259
exitcode = EXIT_FAILURE;
1267
port = (uint16_t)tmpmax;
1269
address = connect_to;
1270
/* Colon in address indicates IPv6 */
1272
if(strchr(address, ':') != NULL){
1282
ret = start_mandos_communication(address, port, if_index, af);
1284
exitcode = EXIT_FAILURE;
1286
exitcode = EXIT_SUCCESS;
1296
AvahiServerConfig config;
1297
/* Do not publish any local Zeroconf records */
1298
avahi_server_config_init(&config);
1299
config.publish_hinfo = 0;
1300
config.publish_addresses = 0;
1301
config.publish_workstation = 0;
1302
config.publish_domain = 0;
1304
/* Allocate a new server */
1305
mc.server = avahi_server_new(avahi_simple_poll_get
1306
(mc.simple_poll), &config, NULL,
1309
/* Free the Avahi configuration data */
1310
avahi_server_config_free(&config);
1313
/* Check if creating the Avahi server object succeeded */
1314
if(mc.server == NULL){
1315
fprintf(stderr, "Failed to create Avahi server: %s\n",
1316
avahi_strerror(error));
1317
exitcode = EXIT_FAILURE;
1325
/* Create the Avahi service browser */
1326
sb = avahi_s_service_browser_new(mc.server, if_index,
1327
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1328
NULL, 0, browse_callback, NULL);
1330
fprintf(stderr, "Failed to create service browser: %s\n",
1331
avahi_strerror(avahi_server_errno(mc.server)));
1332
exitcode = EXIT_FAILURE;
1340
/* Run the main loop */
1343
fprintf(stderr, "Starting Avahi loop search\n");
1346
avahi_simple_poll_loop(mc.simple_poll);
1351
fprintf(stderr, "%s exiting\n", argv[0]);
1354
/* Cleanup things */
1356
avahi_s_service_browser_free(sb);
1358
if(mc.server != NULL)
1359
avahi_server_free(mc.server);
1361
if(mc.simple_poll != NULL)
1362
avahi_simple_poll_free(mc.simple_poll);
1364
if(gnutls_initialized){
1365
gnutls_certificate_free_credentials(mc.cred);
1366
gnutls_global_deinit();
1367
gnutls_dh_params_deinit(mc.dh_params);
1370
if(gpgme_initialized){
1371
gpgme_release(mc.ctx);
1374
/* Take down the network interface */
1375
if(take_down_interface){
1376
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1378
perror("ioctl SIOCGIFFLAGS");
1379
} else if(network.ifr_flags & IFF_UP) {
1380
network.ifr_flags &= ~IFF_UP; /* clear flag */
1381
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1383
perror("ioctl SIOCSIFFLAGS");
1386
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1392
/* Removes the temp directory used by GPGME */
1393
if(tempdir_created){
1395
struct dirent *direntry;
1396
d = opendir(tempdir);
1398
if(errno != ENOENT){
1403
direntry = readdir(d);
1404
if(direntry == NULL){
1407
/* Skip "." and ".." */
1408
if(direntry->d_name[0] == '.'
1409
and (direntry->d_name[1] == '\0'
1410
or (direntry->d_name[1] == '.'
1411
and direntry->d_name[2] == '\0'))){
1414
char *fullname = NULL;
1415
ret = asprintf(&fullname, "%s/%s", tempdir,
1421
ret = remove(fullname);
1423
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1430
ret = rmdir(tempdir);
1431
if(ret == -1 and errno != ENOENT){
1437
ret = sigaction(signal_received, &old_sigterm_action, NULL);
1439
perror("sigaction");
1441
raise(signal_received);