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 © 2008-2012 Teddy Hogeborn
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* Copyright © 2008-2012 Björn Påhlsson
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* 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@recompile.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, srand(),
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(), S_ISREG */
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
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
SIOCSIFFLAGS, if_indextoname(),
70
if_nametoindex(), IF_NAMESIZE */
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit() */
77
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
78
#include <iso646.h> /* not, or, and */
79
#include <argp.h> /* struct argp_option, error_t, struct
80
argp_state, struct argp,
81
argp_parse(), ARGP_KEY_ARG,
82
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
83
#include <signal.h> /* sigemptyset(), sigaddset(),
84
sigaction(), SIGTERM, sig_atomic_t,
86
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
87
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
88
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
89
WEXITSTATUS(), WTERMSIG() */
90
#include <grp.h> /* setgroups() */
93
#include <sys/klog.h> /* klogctl() */
94
#endif /* __linux__ */
97
/* All Avahi types, constants and functions
100
#include <avahi-core/core.h>
101
#include <avahi-core/lookup.h>
102
#include <avahi-core/log.h>
103
#include <avahi-common/simple-watch.h>
104
#include <avahi-common/malloc.h>
105
#include <avahi-common/error.h>
108
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
111
init_gnutls_session(),
113
#include <gnutls/openpgp.h>
114
/* gnutls_certificate_set_openpgp_key_file(),
115
GNUTLS_OPENPGP_FMT_BASE64 */
118
#include <gpgme.h> /* All GPGME types, constants and
121
GPGME_PROTOCOL_OpenPGP,
124
#define BUFFER_SIZE 256
126
#define PATHDIR "/conf/conf.d/mandos"
127
#define SECKEY "seckey.txt"
128
#define PUBKEY "pubkey.txt"
129
#define HOOKDIR "/lib/mandos/network-hooks.d"
132
static const char mandos_protocol_version[] = "1";
133
const char *argp_program_version = "mandos-client " VERSION;
134
const char *argp_program_bug_address = "<mandos@recompile.se>";
135
static const char sys_class_net[] = "/sys/class/net";
136
char *connect_to = NULL;
137
const char *hookdir = HOOKDIR;
139
/* Doubly linked list that need to be circularly linked when used */
140
typedef struct server{
143
AvahiIfIndex if_index;
145
struct timespec last_seen;
150
/* Used for passing in values through the Avahi callback functions */
152
AvahiSimplePoll *simple_poll;
154
gnutls_certificate_credentials_t cred;
155
unsigned int dh_bits;
156
gnutls_dh_params_t dh_params;
157
const char *priority;
159
server *current_server;
162
/* global context so signal handler can reach it*/
163
mandos_context mc = { .simple_poll = NULL, .server = NULL,
164
.dh_bits = 1024, .priority = "SECURE256"
165
":!CTYPE-X.509:+CTYPE-OPENPGP",
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.current_server = NULL };
168
sig_atomic_t quit_now = 0;
169
int signal_received = 0;
171
/* Function to use when printing errors */
172
void perror_plus(const char *print_text){
174
fprintf(stderr, "Mandos plugin %s: ",
175
program_invocation_short_name);
180
__attribute__((format (gnu_printf, 2, 3)))
181
int fprintf_plus(FILE *stream, const char *format, ...){
183
va_start (ap, format);
185
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
186
program_invocation_short_name));
187
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
191
* Make additional room in "buffer" for at least BUFFER_SIZE more
192
* bytes. "buffer_capacity" is how much is currently allocated,
193
* "buffer_length" is how much is already used.
195
size_t incbuffer(char **buffer, size_t buffer_length,
196
size_t buffer_capacity){
197
if(buffer_length + BUFFER_SIZE > buffer_capacity){
198
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
202
buffer_capacity += BUFFER_SIZE;
204
return buffer_capacity;
207
/* Add server to set of servers to retry periodically */
208
bool add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,
211
server *new_server = malloc(sizeof(server));
212
if(new_server == NULL){
213
perror_plus("malloc");
216
*new_server = (server){ .ip = strdup(ip),
218
.if_index = if_index,
220
if(new_server->ip == NULL){
221
perror_plus("strdup");
224
/* Special case of first server */
225
if (mc.current_server == NULL){
226
new_server->next = new_server;
227
new_server->prev = new_server;
228
mc.current_server = new_server;
229
/* Place the new server last in the list */
231
new_server->next = mc.current_server;
232
new_server->prev = mc.current_server->prev;
233
new_server->prev->next = new_server;
234
mc.current_server->prev = new_server;
236
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
238
perror_plus("clock_gettime");
247
static bool init_gpgme(const char *seckey, const char *pubkey,
248
const char *tempdir){
250
gpgme_engine_info_t engine_info;
254
* Helper function to insert pub and seckey to the engine keyring.
256
bool import_key(const char *filename){
259
gpgme_data_t pgp_data;
261
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
267
rc = gpgme_data_new_from_fd(&pgp_data, fd);
268
if(rc != GPG_ERR_NO_ERROR){
269
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
270
gpgme_strsource(rc), gpgme_strerror(rc));
274
rc = gpgme_op_import(mc.ctx, pgp_data);
275
if(rc != GPG_ERR_NO_ERROR){
276
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
281
ret = (int)TEMP_FAILURE_RETRY(close(fd));
283
perror_plus("close");
285
gpgme_data_release(pgp_data);
290
fprintf_plus(stderr, "Initializing GPGME\n");
294
gpgme_check_version(NULL);
295
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
296
if(rc != GPG_ERR_NO_ERROR){
297
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
298
gpgme_strsource(rc), gpgme_strerror(rc));
302
/* Set GPGME home directory for the OpenPGP engine only */
303
rc = gpgme_get_engine_info(&engine_info);
304
if(rc != GPG_ERR_NO_ERROR){
305
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
306
gpgme_strsource(rc), gpgme_strerror(rc));
309
while(engine_info != NULL){
310
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
311
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
312
engine_info->file_name, tempdir);
315
engine_info = engine_info->next;
317
if(engine_info == NULL){
318
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
323
/* Create new GPGME "context" */
324
rc = gpgme_new(&(mc.ctx));
325
if(rc != GPG_ERR_NO_ERROR){
326
fprintf_plus(stderr, "Mandos plugin mandos-client: "
327
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
332
if(not import_key(pubkey) or not import_key(seckey)){
340
* Decrypt OpenPGP data.
341
* Returns -1 on error
343
static ssize_t pgp_packet_decrypt(const char *cryptotext,
346
gpgme_data_t dh_crypto, dh_plain;
349
size_t plaintext_capacity = 0;
350
ssize_t plaintext_length = 0;
353
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
356
/* Create new GPGME data buffer from memory cryptotext */
357
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
359
if(rc != GPG_ERR_NO_ERROR){
360
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
361
gpgme_strsource(rc), gpgme_strerror(rc));
365
/* Create new empty GPGME data buffer for the plaintext */
366
rc = gpgme_data_new(&dh_plain);
367
if(rc != GPG_ERR_NO_ERROR){
368
fprintf_plus(stderr, "Mandos plugin mandos-client: "
369
"bad gpgme_data_new: %s: %s\n",
370
gpgme_strsource(rc), gpgme_strerror(rc));
371
gpgme_data_release(dh_crypto);
375
/* Decrypt data from the cryptotext data buffer to the plaintext
377
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
378
if(rc != GPG_ERR_NO_ERROR){
379
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
380
gpgme_strsource(rc), gpgme_strerror(rc));
381
plaintext_length = -1;
383
gpgme_decrypt_result_t result;
384
result = gpgme_op_decrypt_result(mc.ctx);
386
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
388
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
389
result->unsupported_algorithm);
390
fprintf_plus(stderr, "Wrong key usage: %u\n",
391
result->wrong_key_usage);
392
if(result->file_name != NULL){
393
fprintf_plus(stderr, "File name: %s\n", result->file_name);
395
gpgme_recipient_t recipient;
396
recipient = result->recipients;
397
while(recipient != NULL){
398
fprintf_plus(stderr, "Public key algorithm: %s\n",
399
gpgme_pubkey_algo_name
400
(recipient->pubkey_algo));
401
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
402
fprintf_plus(stderr, "Secret key available: %s\n",
403
recipient->status == GPG_ERR_NO_SECKEY
405
recipient = recipient->next;
413
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
416
/* Seek back to the beginning of the GPGME plaintext data buffer */
417
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
418
perror_plus("gpgme_data_seek");
419
plaintext_length = -1;
425
plaintext_capacity = incbuffer(plaintext,
426
(size_t)plaintext_length,
428
if(plaintext_capacity == 0){
429
perror_plus("incbuffer");
430
plaintext_length = -1;
434
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
436
/* Print the data, if any */
442
perror_plus("gpgme_data_read");
443
plaintext_length = -1;
446
plaintext_length += ret;
450
fprintf_plus(stderr, "Decrypted password is: ");
451
for(ssize_t i = 0; i < plaintext_length; i++){
452
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
454
fprintf(stderr, "\n");
459
/* Delete the GPGME cryptotext data buffer */
460
gpgme_data_release(dh_crypto);
462
/* Delete the GPGME plaintext data buffer */
463
gpgme_data_release(dh_plain);
464
return plaintext_length;
467
static const char * safer_gnutls_strerror(int value){
468
const char *ret = gnutls_strerror(value); /* Spurious warning from
469
-Wunreachable-code */
475
/* GnuTLS log function callback */
476
static void debuggnutls(__attribute__((unused)) int level,
478
fprintf_plus(stderr, "GnuTLS: %s", string);
481
static int init_gnutls_global(const char *pubkeyfilename,
482
const char *seckeyfilename){
486
fprintf_plus(stderr, "Initializing GnuTLS\n");
489
ret = gnutls_global_init();
490
if(ret != GNUTLS_E_SUCCESS){
491
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
492
safer_gnutls_strerror(ret));
497
/* "Use a log level over 10 to enable all debugging options."
500
gnutls_global_set_log_level(11);
501
gnutls_global_set_log_function(debuggnutls);
504
/* OpenPGP credentials */
505
ret = gnutls_certificate_allocate_credentials(&mc.cred);
506
if(ret != GNUTLS_E_SUCCESS){
507
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
508
safer_gnutls_strerror(ret));
509
gnutls_global_deinit();
514
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
515
" secret key %s as GnuTLS credentials\n",
520
ret = gnutls_certificate_set_openpgp_key_file
521
(mc.cred, pubkeyfilename, seckeyfilename,
522
GNUTLS_OPENPGP_FMT_BASE64);
523
if(ret != GNUTLS_E_SUCCESS){
525
"Error[%d] while reading the OpenPGP key pair ('%s',"
526
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
527
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
528
safer_gnutls_strerror(ret));
532
/* GnuTLS server initialization */
533
ret = gnutls_dh_params_init(&mc.dh_params);
534
if(ret != GNUTLS_E_SUCCESS){
535
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
536
" initialization: %s\n",
537
safer_gnutls_strerror(ret));
540
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
541
if(ret != GNUTLS_E_SUCCESS){
542
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
543
safer_gnutls_strerror(ret));
547
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
553
gnutls_certificate_free_credentials(mc.cred);
554
gnutls_global_deinit();
555
gnutls_dh_params_deinit(mc.dh_params);
559
static int init_gnutls_session(gnutls_session_t *session){
561
/* GnuTLS session creation */
563
ret = gnutls_init(session, GNUTLS_SERVER);
567
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
568
if(ret != GNUTLS_E_SUCCESS){
570
"Error in GnuTLS session initialization: %s\n",
571
safer_gnutls_strerror(ret));
577
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
579
gnutls_deinit(*session);
582
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
583
if(ret != GNUTLS_E_SUCCESS){
584
fprintf_plus(stderr, "Syntax error at: %s\n", err);
585
fprintf_plus(stderr, "GnuTLS error: %s\n",
586
safer_gnutls_strerror(ret));
587
gnutls_deinit(*session);
593
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
596
gnutls_deinit(*session);
599
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
600
if(ret != GNUTLS_E_SUCCESS){
601
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
602
safer_gnutls_strerror(ret));
603
gnutls_deinit(*session);
607
/* ignore client certificate if any. */
608
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
610
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
615
/* Avahi log function callback */
616
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
617
__attribute__((unused)) const char *txt){}
619
/* Called when a Mandos server is found */
620
static int start_mandos_communication(const char *ip, uint16_t port,
621
AvahiIfIndex if_index,
623
int ret, tcp_sd = -1;
626
struct sockaddr_in in;
627
struct sockaddr_in6 in6;
630
char *decrypted_buffer = NULL;
631
size_t buffer_length = 0;
632
size_t buffer_capacity = 0;
635
gnutls_session_t session;
636
int pf; /* Protocol family */
653
fprintf_plus(stderr, "Bad address family: %d\n", af);
658
ret = init_gnutls_session(&session);
664
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
665
PRIu16 "\n", ip, port);
668
tcp_sd = socket(pf, SOCK_STREAM, 0);
671
perror_plus("socket");
681
memset(&to, 0, sizeof(to));
683
to.in6.sin6_family = (sa_family_t)af;
684
ret = inet_pton(af, ip, &to.in6.sin6_addr);
686
to.in.sin_family = (sa_family_t)af;
687
ret = inet_pton(af, ip, &to.in.sin_addr);
691
perror_plus("inet_pton");
697
fprintf_plus(stderr, "Bad address: %s\n", ip);
702
to.in6.sin6_port = htons(port); /* Spurious warnings from
704
-Wunreachable-code */
706
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
707
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
709
if(if_index == AVAHI_IF_UNSPEC){
710
fprintf_plus(stderr, "An IPv6 link-local address is"
711
" incomplete without a network interface\n");
715
/* Set the network interface number as scope */
716
to.in6.sin6_scope_id = (uint32_t)if_index;
719
to.in.sin_port = htons(port); /* Spurious warnings from
721
-Wunreachable-code */
730
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
731
char interface[IF_NAMESIZE];
732
if(if_indextoname((unsigned int)if_index, interface) == NULL){
733
perror_plus("if_indextoname");
735
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
736
"\n", ip, interface, port);
739
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
742
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
743
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
746
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
749
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
753
perror_plus("inet_ntop");
755
if(strcmp(addrstr, ip) != 0){
756
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
767
ret = connect(tcp_sd, &to.in6, sizeof(to));
769
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
772
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
774
perror_plus("connect");
785
const char *out = mandos_protocol_version;
788
size_t out_size = strlen(out);
789
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
790
out_size - written));
793
perror_plus("write");
797
written += (size_t)ret;
798
if(written < out_size){
801
if(out == mandos_protocol_version){
816
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
824
/* Spurious warning from -Wint-to-pointer-cast */
825
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
833
ret = gnutls_handshake(session);
838
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
840
if(ret != GNUTLS_E_SUCCESS){
842
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
849
/* Read OpenPGP packet that contains the wanted password */
852
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
863
buffer_capacity = incbuffer(&buffer, buffer_length,
865
if(buffer_capacity == 0){
867
perror_plus("incbuffer");
877
sret = gnutls_record_recv(session, buffer+buffer_length,
884
case GNUTLS_E_INTERRUPTED:
887
case GNUTLS_E_REHANDSHAKE:
889
ret = gnutls_handshake(session);
895
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
897
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
905
fprintf_plus(stderr, "Unknown error while reading data from"
906
" encrypted session with Mandos server\n");
907
gnutls_bye(session, GNUTLS_SHUT_RDWR);
912
buffer_length += (size_t) sret;
917
fprintf_plus(stderr, "Closing TLS session\n");
926
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
931
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
933
if(buffer_length > 0){
934
ssize_t decrypted_buffer_size;
935
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
937
if(decrypted_buffer_size >= 0){
940
while(written < (size_t) decrypted_buffer_size){
946
ret = (int)fwrite(decrypted_buffer + written, 1,
947
(size_t)decrypted_buffer_size - written,
949
if(ret == 0 and ferror(stdout)){
952
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
958
written += (size_t)ret;
964
/* Shutdown procedure */
969
free(decrypted_buffer);
972
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
978
perror_plus("close");
980
gnutls_deinit(session);
990
static void resolve_callback(AvahiSServiceResolver *r,
991
AvahiIfIndex interface,
993
AvahiResolverEvent event,
997
const char *host_name,
998
const AvahiAddress *address,
1000
AVAHI_GCC_UNUSED AvahiStringList *txt,
1001
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1003
AVAHI_GCC_UNUSED void* userdata){
1006
/* Called whenever a service has been resolved successfully or
1015
case AVAHI_RESOLVER_FAILURE:
1016
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1017
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1019
avahi_strerror(avahi_server_errno(mc.server)));
1022
case AVAHI_RESOLVER_FOUND:
1024
char ip[AVAHI_ADDRESS_STR_MAX];
1025
avahi_address_snprint(ip, sizeof(ip), address);
1027
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1028
PRIdMAX ") on port %" PRIu16 "\n", name,
1029
host_name, ip, (intmax_t)interface, port);
1031
int ret = start_mandos_communication(ip, port, interface,
1032
avahi_proto_to_af(proto));
1034
avahi_simple_poll_quit(mc.simple_poll);
1036
if(not add_server(ip, port, interface,
1037
avahi_proto_to_af(proto))){
1038
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1044
avahi_s_service_resolver_free(r);
1047
static void browse_callback(AvahiSServiceBrowser *b,
1048
AvahiIfIndex interface,
1049
AvahiProtocol protocol,
1050
AvahiBrowserEvent event,
1054
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1056
AVAHI_GCC_UNUSED void* userdata){
1059
/* Called whenever a new services becomes available on the LAN or
1060
is removed from the LAN */
1068
case AVAHI_BROWSER_FAILURE:
1070
fprintf_plus(stderr, "(Avahi browser) %s\n",
1071
avahi_strerror(avahi_server_errno(mc.server)));
1072
avahi_simple_poll_quit(mc.simple_poll);
1075
case AVAHI_BROWSER_NEW:
1076
/* We ignore the returned Avahi resolver object. In the callback
1077
function we free it. If the Avahi server is terminated before
1078
the callback function is called the Avahi server will free the
1081
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1082
name, type, domain, protocol, 0,
1083
resolve_callback, NULL) == NULL)
1084
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1086
avahi_strerror(avahi_server_errno(mc.server)));
1089
case AVAHI_BROWSER_REMOVE:
1092
case AVAHI_BROWSER_ALL_FOR_NOW:
1093
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1095
fprintf_plus(stderr, "No Mandos server found, still"
1102
/* Signal handler that stops main loop after SIGTERM */
1103
static void handle_sigterm(int sig){
1108
signal_received = sig;
1109
int old_errno = errno;
1110
/* set main loop to exit */
1111
if(mc.simple_poll != NULL){
1112
avahi_simple_poll_quit(mc.simple_poll);
1117
bool get_flags(const char *ifname, struct ifreq *ifr){
1120
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1122
perror_plus("socket");
1125
strcpy(ifr->ifr_name, ifname);
1126
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1129
perror_plus("ioctl SIOCGIFFLAGS");
1136
bool good_flags(const char *ifname, const struct ifreq *ifr){
1138
/* Reject the loopback device */
1139
if(ifr->ifr_flags & IFF_LOOPBACK){
1141
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1146
/* Accept point-to-point devices only if connect_to is specified */
1147
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1149
fprintf_plus(stderr, "Accepting point-to-point interface"
1150
" \"%s\"\n", ifname);
1154
/* Otherwise, reject non-broadcast-capable devices */
1155
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1157
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1158
" \"%s\"\n", ifname);
1162
/* Reject non-ARP interfaces (including dummy interfaces) */
1163
if(ifr->ifr_flags & IFF_NOARP){
1165
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1171
/* Accept this device */
1173
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1179
* This function determines if a directory entry in /sys/class/net
1180
* corresponds to an acceptable network device.
1181
* (This function is passed to scandir(3) as a filter function.)
1183
int good_interface(const struct dirent *if_entry){
1184
if(if_entry->d_name[0] == '.'){
1189
if(not get_flags(if_entry->d_name, &ifr)){
1191
fprintf_plus(stderr, "Failed to get flags for interface "
1192
"\"%s\"\n", if_entry->d_name);
1197
if(not good_flags(if_entry->d_name, &ifr)){
1204
* This function determines if a directory entry in /sys/class/net
1205
* corresponds to an acceptable network device which is up.
1206
* (This function is passed to scandir(3) as a filter function.)
1208
int up_interface(const struct dirent *if_entry){
1209
if(if_entry->d_name[0] == '.'){
1214
if(not get_flags(if_entry->d_name, &ifr)){
1216
fprintf_plus(stderr, "Failed to get flags for interface "
1217
"\"%s\"\n", if_entry->d_name);
1222
/* Reject down interfaces */
1223
if(not (ifr.ifr_flags & IFF_UP)){
1225
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1231
/* Reject non-running interfaces */
1232
if(not (ifr.ifr_flags & IFF_RUNNING)){
1234
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1240
if(not good_flags(if_entry->d_name, &ifr)){
1246
int notdotentries(const struct dirent *direntry){
1247
/* Skip "." and ".." */
1248
if(direntry->d_name[0] == '.'
1249
and (direntry->d_name[1] == '\0'
1250
or (direntry->d_name[1] == '.'
1251
and direntry->d_name[2] == '\0'))){
1257
/* Is this directory entry a runnable program? */
1258
int runnable_hook(const struct dirent *direntry){
1263
if((direntry->d_name)[0] == '\0'){
1268
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1269
"abcdefghijklmnopqrstuvwxyz"
1272
if((direntry->d_name)[sret] != '\0'){
1273
/* Contains non-allowed characters */
1275
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1281
char *fullname = NULL;
1282
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1284
perror_plus("asprintf");
1288
ret = stat(fullname, &st);
1291
perror_plus("Could not stat hook");
1295
if(not (S_ISREG(st.st_mode))){
1296
/* Not a regular file */
1298
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1303
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1304
/* Not executable */
1306
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1312
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1318
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1320
struct timespec now;
1321
struct timespec waited_time;
1322
intmax_t block_time;
1325
if(mc.current_server == NULL){
1327
fprintf_plus(stderr, "Wait until first server is found."
1330
ret = avahi_simple_poll_iterate(s, -1);
1333
fprintf_plus(stderr, "Check current_server if we should run"
1336
/* the current time */
1337
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1339
perror_plus("clock_gettime");
1342
/* Calculating in ms how long time between now and server
1343
who we visted longest time ago. Now - last seen. */
1344
waited_time.tv_sec = (now.tv_sec
1345
- mc.current_server->last_seen.tv_sec);
1346
waited_time.tv_nsec = (now.tv_nsec
1347
- mc.current_server->last_seen.tv_nsec);
1348
/* total time is 10s/10,000ms.
1349
Converting to s from ms by dividing by 1,000,
1350
and ns to ms by dividing by 1,000,000. */
1351
block_time = ((retry_interval
1352
- ((intmax_t)waited_time.tv_sec * 1000))
1353
- ((intmax_t)waited_time.tv_nsec / 1000000));
1356
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1360
if(block_time <= 0){
1361
ret = start_mandos_communication(mc.current_server->ip,
1362
mc.current_server->port,
1363
mc.current_server->if_index,
1364
mc.current_server->af);
1366
avahi_simple_poll_quit(mc.simple_poll);
1369
ret = clock_gettime(CLOCK_MONOTONIC,
1370
&mc.current_server->last_seen);
1372
perror_plus("clock_gettime");
1375
mc.current_server = mc.current_server->next;
1376
block_time = 0; /* Call avahi to find new Mandos
1377
servers, but don't block */
1380
ret = avahi_simple_poll_iterate(s, (int)block_time);
1383
if (ret > 0 or errno != EINTR){
1384
return (ret != 1) ? ret : 0;
1390
bool run_network_hooks(const char *mode, const char *interface,
1392
struct dirent **direntries;
1393
struct dirent *direntry;
1395
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1398
perror_plus("scandir");
1400
int devnull = open("/dev/null", O_RDONLY);
1401
for(int i = 0; i < numhooks; i++){
1402
direntry = direntries[i];
1403
char *fullname = NULL;
1404
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1406
perror_plus("asprintf");
1410
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1413
pid_t hook_pid = fork();
1416
/* Raise privileges */
1420
perror_plus("seteuid");
1422
/* Raise privileges even more */
1426
perror_plus("setuid");
1432
perror_plus("setgid");
1434
/* Reset supplementary groups */
1436
ret = setgroups(0, NULL);
1438
perror_plus("setgroups");
1440
dup2(devnull, STDIN_FILENO);
1442
dup2(STDERR_FILENO, STDOUT_FILENO);
1443
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1445
perror_plus("setenv");
1448
ret = setenv("DEVICE", interface, 1);
1450
perror_plus("setenv");
1453
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1455
perror_plus("setenv");
1458
ret = setenv("MODE", mode, 1);
1460
perror_plus("setenv");
1464
ret = asprintf(&delaystring, "%f", delay);
1466
perror_plus("asprintf");
1469
ret = setenv("DELAY", delaystring, 1);
1472
perror_plus("setenv");
1476
if(connect_to != NULL){
1477
ret = setenv("CONNECT", connect_to, 1);
1479
perror_plus("setenv");
1483
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1484
perror_plus("execl");
1485
_exit(EXIT_FAILURE);
1489
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1490
perror_plus("waitpid");
1494
if(WIFEXITED(status)){
1495
if(WEXITSTATUS(status) != 0){
1496
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1497
" with status %d\n", direntry->d_name,
1498
WEXITSTATUS(status));
1502
} else if(WIFSIGNALED(status)){
1503
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1504
" signal %d\n", direntry->d_name,
1509
fprintf_plus(stderr, "Warning: network hook \"%s\""
1510
" crashed\n", direntry->d_name);
1517
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1526
int main(int argc, char *argv[]){
1527
AvahiSServiceBrowser *sb = NULL;
1532
int exitcode = EXIT_SUCCESS;
1533
const char *interface = "";
1534
struct ifreq network;
1536
bool take_down_interface = false;
1539
char tempdir[] = "/tmp/mandosXXXXXX";
1540
bool tempdir_created = false;
1541
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1542
const char *seckey = PATHDIR "/" SECKEY;
1543
const char *pubkey = PATHDIR "/" PUBKEY;
1545
bool gnutls_initialized = false;
1546
bool gpgme_initialized = false;
1548
double retry_interval = 10; /* 10s between trying a server and
1549
retrying the same server again */
1551
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1552
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1557
/* Lower any group privileges we might have, just to be safe */
1561
perror_plus("setgid");
1564
/* Lower user privileges (temporarily) */
1568
perror_plus("seteuid");
1576
struct argp_option options[] = {
1577
{ .name = "debug", .key = 128,
1578
.doc = "Debug mode", .group = 3 },
1579
{ .name = "connect", .key = 'c',
1580
.arg = "ADDRESS:PORT",
1581
.doc = "Connect directly to a specific Mandos server",
1583
{ .name = "interface", .key = 'i',
1585
.doc = "Network interface that will be used to search for"
1588
{ .name = "seckey", .key = 's',
1590
.doc = "OpenPGP secret key file base name",
1592
{ .name = "pubkey", .key = 'p',
1594
.doc = "OpenPGP public key file base name",
1596
{ .name = "dh-bits", .key = 129,
1598
.doc = "Bit length of the prime number used in the"
1599
" Diffie-Hellman key exchange",
1601
{ .name = "priority", .key = 130,
1603
.doc = "GnuTLS priority string for the TLS handshake",
1605
{ .name = "delay", .key = 131,
1607
.doc = "Maximum delay to wait for interface startup",
1609
{ .name = "retry", .key = 132,
1611
.doc = "Retry interval used when denied by the Mandos server",
1613
{ .name = "network-hook-dir", .key = 133,
1615
.doc = "Directory where network hooks are located",
1618
* These reproduce what we would get without ARGP_NO_HELP
1620
{ .name = "help", .key = '?',
1621
.doc = "Give this help list", .group = -1 },
1622
{ .name = "usage", .key = -3,
1623
.doc = "Give a short usage message", .group = -1 },
1624
{ .name = "version", .key = 'V',
1625
.doc = "Print program version", .group = -1 },
1629
error_t parse_opt(int key, char *arg,
1630
struct argp_state *state){
1633
case 128: /* --debug */
1636
case 'c': /* --connect */
1639
case 'i': /* --interface */
1642
case 's': /* --seckey */
1645
case 'p': /* --pubkey */
1648
case 129: /* --dh-bits */
1650
tmpmax = strtoimax(arg, &tmp, 10);
1651
if(errno != 0 or tmp == arg or *tmp != '\0'
1652
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1653
argp_error(state, "Bad number of DH bits");
1655
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1657
case 130: /* --priority */
1660
case 131: /* --delay */
1662
delay = strtof(arg, &tmp);
1663
if(errno != 0 or tmp == arg or *tmp != '\0'){
1664
argp_error(state, "Bad delay");
1666
case 132: /* --retry */
1668
retry_interval = strtod(arg, &tmp);
1669
if(errno != 0 or tmp == arg or *tmp != '\0'
1670
or (retry_interval * 1000) > INT_MAX
1671
or retry_interval < 0){
1672
argp_error(state, "Bad retry interval");
1675
case 133: /* --network-hook-dir */
1679
* These reproduce what we would get without ARGP_NO_HELP
1681
case '?': /* --help */
1682
argp_state_help(state, state->out_stream,
1683
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1684
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1685
case -3: /* --usage */
1686
argp_state_help(state, state->out_stream,
1687
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1688
case 'V': /* --version */
1689
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1690
exit(argp_err_exit_status);
1693
return ARGP_ERR_UNKNOWN;
1698
struct argp argp = { .options = options, .parser = parse_opt,
1700
.doc = "Mandos client -- Get and decrypt"
1701
" passwords from a Mandos server" };
1702
ret = argp_parse(&argp, argc, argv,
1703
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1710
perror_plus("argp_parse");
1711
exitcode = EX_OSERR;
1714
exitcode = EX_USAGE;
1720
/* Work around Debian bug #633582:
1721
<http://bugs.debian.org/633582> */
1723
/* Re-raise priviliges */
1727
perror_plus("seteuid");
1731
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1732
int seckey_fd = open(seckey, O_RDONLY);
1733
if(seckey_fd == -1){
1734
perror_plus("open");
1736
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1738
perror_plus("fstat");
1740
if(S_ISREG(st.st_mode)
1741
and st.st_uid == 0 and st.st_gid == 0){
1742
ret = fchown(seckey_fd, uid, gid);
1744
perror_plus("fchown");
1748
TEMP_FAILURE_RETRY(close(seckey_fd));
1752
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1753
int pubkey_fd = open(pubkey, O_RDONLY);
1754
if(pubkey_fd == -1){
1755
perror_plus("open");
1757
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1759
perror_plus("fstat");
1761
if(S_ISREG(st.st_mode)
1762
and st.st_uid == 0 and st.st_gid == 0){
1763
ret = fchown(pubkey_fd, uid, gid);
1765
perror_plus("fchown");
1769
TEMP_FAILURE_RETRY(close(pubkey_fd));
1773
/* Lower privileges */
1777
perror_plus("seteuid");
1782
/* Run network hooks */
1783
if(not run_network_hooks("start", interface, delay)){
1788
avahi_set_log_function(empty_log);
1791
if(interface[0] == '\0'){
1792
struct dirent **direntries;
1793
/* First look for interfaces that are up */
1794
ret = scandir(sys_class_net, &direntries, up_interface,
1797
/* No up interfaces, look for any good interfaces */
1799
ret = scandir(sys_class_net, &direntries, good_interface,
1803
/* Pick the first interface returned */
1804
interface = strdup(direntries[0]->d_name);
1806
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1808
if(interface == NULL){
1809
perror_plus("malloc");
1811
exitcode = EXIT_FAILURE;
1817
fprintf_plus(stderr, "Could not find a network interface\n");
1818
exitcode = EXIT_FAILURE;
1823
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1824
from the signal handler */
1825
/* Initialize the pseudo-RNG for Avahi */
1826
srand((unsigned int) time(NULL));
1827
mc.simple_poll = avahi_simple_poll_new();
1828
if(mc.simple_poll == NULL){
1829
fprintf_plus(stderr,
1830
"Avahi: Failed to create simple poll object.\n");
1831
exitcode = EX_UNAVAILABLE;
1835
sigemptyset(&sigterm_action.sa_mask);
1836
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1838
perror_plus("sigaddset");
1839
exitcode = EX_OSERR;
1842
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1844
perror_plus("sigaddset");
1845
exitcode = EX_OSERR;
1848
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1850
perror_plus("sigaddset");
1851
exitcode = EX_OSERR;
1854
/* Need to check if the handler is SIG_IGN before handling:
1855
| [[info:libc:Initial Signal Actions]] |
1856
| [[info:libc:Basic Signal Handling]] |
1858
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1860
perror_plus("sigaction");
1863
if(old_sigterm_action.sa_handler != SIG_IGN){
1864
ret = sigaction(SIGINT, &sigterm_action, NULL);
1866
perror_plus("sigaction");
1867
exitcode = EX_OSERR;
1871
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1873
perror_plus("sigaction");
1876
if(old_sigterm_action.sa_handler != SIG_IGN){
1877
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1879
perror_plus("sigaction");
1880
exitcode = EX_OSERR;
1884
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1886
perror_plus("sigaction");
1889
if(old_sigterm_action.sa_handler != SIG_IGN){
1890
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1892
perror_plus("sigaction");
1893
exitcode = EX_OSERR;
1898
/* If the interface is down, bring it up */
1899
if(strcmp(interface, "none") != 0){
1900
if_index = (AvahiIfIndex) if_nametoindex(interface);
1902
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1903
exitcode = EX_UNAVAILABLE;
1911
/* Re-raise priviliges */
1915
perror_plus("seteuid");
1919
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1920
messages about the network interface to mess up the prompt */
1921
ret = klogctl(8, NULL, 5);
1922
bool restore_loglevel = true;
1924
restore_loglevel = false;
1925
perror_plus("klogctl");
1927
#endif /* __linux__ */
1929
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1931
perror_plus("socket");
1932
exitcode = EX_OSERR;
1934
if(restore_loglevel){
1935
ret = klogctl(7, NULL, 0);
1937
perror_plus("klogctl");
1940
#endif /* __linux__ */
1941
/* Lower privileges */
1945
perror_plus("seteuid");
1949
strcpy(network.ifr_name, interface);
1950
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1952
perror_plus("ioctl SIOCGIFFLAGS");
1954
if(restore_loglevel){
1955
ret = klogctl(7, NULL, 0);
1957
perror_plus("klogctl");
1960
#endif /* __linux__ */
1961
exitcode = EX_OSERR;
1962
/* Lower privileges */
1966
perror_plus("seteuid");
1970
if((network.ifr_flags & IFF_UP) == 0){
1971
network.ifr_flags |= IFF_UP;
1972
take_down_interface = true;
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1975
take_down_interface = false;
1976
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1977
exitcode = EX_OSERR;
1979
if(restore_loglevel){
1980
ret = klogctl(7, NULL, 0);
1982
perror_plus("klogctl");
1985
#endif /* __linux__ */
1986
/* Lower privileges */
1990
perror_plus("seteuid");
1995
/* Sleep checking until interface is running.
1996
Check every 0.25s, up to total time of delay */
1997
for(int i=0; i < delay * 4; i++){
1998
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2000
perror_plus("ioctl SIOCGIFFLAGS");
2001
} else if(network.ifr_flags & IFF_RUNNING){
2004
struct timespec sleeptime = { .tv_nsec = 250000000 };
2005
ret = nanosleep(&sleeptime, NULL);
2006
if(ret == -1 and errno != EINTR){
2007
perror_plus("nanosleep");
2010
if(not take_down_interface){
2011
/* We won't need the socket anymore */
2012
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2014
perror_plus("close");
2018
if(restore_loglevel){
2019
/* Restores kernel loglevel to default */
2020
ret = klogctl(7, NULL, 0);
2022
perror_plus("klogctl");
2025
#endif /* __linux__ */
2026
/* Lower privileges */
2028
/* Lower privileges */
2031
perror_plus("seteuid");
2039
ret = init_gnutls_global(pubkey, seckey);
2041
fprintf_plus(stderr, "init_gnutls_global failed\n");
2042
exitcode = EX_UNAVAILABLE;
2045
gnutls_initialized = true;
2052
if(mkdtemp(tempdir) == NULL){
2053
perror_plus("mkdtemp");
2056
tempdir_created = true;
2062
if(not init_gpgme(pubkey, seckey, tempdir)){
2063
fprintf_plus(stderr, "init_gpgme failed\n");
2064
exitcode = EX_UNAVAILABLE;
2067
gpgme_initialized = true;
2074
if(connect_to != NULL){
2075
/* Connect directly, do not use Zeroconf */
2076
/* (Mainly meant for debugging) */
2077
char *address = strrchr(connect_to, ':');
2078
if(address == NULL){
2079
fprintf_plus(stderr, "No colon in address\n");
2080
exitcode = EX_USAGE;
2090
tmpmax = strtoimax(address+1, &tmp, 10);
2091
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2092
or tmpmax != (uint16_t)tmpmax){
2093
fprintf_plus(stderr, "Bad port number\n");
2094
exitcode = EX_USAGE;
2102
port = (uint16_t)tmpmax;
2104
/* Colon in address indicates IPv6 */
2106
if(strchr(connect_to, ':') != NULL){
2108
/* Accept [] around IPv6 address - see RFC 5952 */
2109
if(connect_to[0] == '[' and address[-1] == ']')
2117
address = connect_to;
2123
while(not quit_now){
2124
ret = start_mandos_communication(address, port, if_index, af);
2125
if(quit_now or ret == 0){
2129
fprintf_plus(stderr, "Retrying in %d seconds\n",
2130
(int)retry_interval);
2132
sleep((int)retry_interval);
2136
exitcode = EXIT_SUCCESS;
2147
AvahiServerConfig config;
2148
/* Do not publish any local Zeroconf records */
2149
avahi_server_config_init(&config);
2150
config.publish_hinfo = 0;
2151
config.publish_addresses = 0;
2152
config.publish_workstation = 0;
2153
config.publish_domain = 0;
2155
/* Allocate a new server */
2156
mc.server = avahi_server_new(avahi_simple_poll_get
2157
(mc.simple_poll), &config, NULL,
2160
/* Free the Avahi configuration data */
2161
avahi_server_config_free(&config);
2164
/* Check if creating the Avahi server object succeeded */
2165
if(mc.server == NULL){
2166
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2167
avahi_strerror(error));
2168
exitcode = EX_UNAVAILABLE;
2176
/* Create the Avahi service browser */
2177
sb = avahi_s_service_browser_new(mc.server, if_index,
2178
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2179
NULL, 0, browse_callback, NULL);
2181
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2182
avahi_strerror(avahi_server_errno(mc.server)));
2183
exitcode = EX_UNAVAILABLE;
2191
/* Run the main loop */
2194
fprintf_plus(stderr, "Starting Avahi loop search\n");
2197
ret = avahi_loop_with_timeout(mc.simple_poll,
2198
(int)(retry_interval * 1000));
2200
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2201
(ret == 0) ? "successfully" : "with error");
2207
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2210
/* Cleanup things */
2212
avahi_s_service_browser_free(sb);
2214
if(mc.server != NULL)
2215
avahi_server_free(mc.server);
2217
if(mc.simple_poll != NULL)
2218
avahi_simple_poll_free(mc.simple_poll);
2220
if(gnutls_initialized){
2221
gnutls_certificate_free_credentials(mc.cred);
2222
gnutls_global_deinit();
2223
gnutls_dh_params_deinit(mc.dh_params);
2226
if(gpgme_initialized){
2227
gpgme_release(mc.ctx);
2230
/* Cleans up the circular linked list of Mandos servers the client
2232
if(mc.current_server != NULL){
2233
mc.current_server->prev->next = NULL;
2234
while(mc.current_server != NULL){
2235
server *next = mc.current_server->next;
2236
free(mc.current_server);
2237
mc.current_server = next;
2241
/* Run network hooks */
2242
run_network_hooks("stop", interface, delay);
2244
/* Re-raise priviliges */
2249
perror_plus("seteuid");
2252
/* Take down the network interface */
2253
if(take_down_interface and geteuid() == 0){
2254
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2256
perror_plus("ioctl SIOCGIFFLAGS");
2257
} else if(network.ifr_flags & IFF_UP){
2258
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2259
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2261
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2264
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2266
perror_plus("close");
2270
/* Lower privileges permanently */
2274
perror_plus("setuid");
2277
/* Removes the GPGME temp directory and all files inside */
2278
if(tempdir_created){
2279
struct dirent **direntries = NULL;
2280
struct dirent *direntry = NULL;
2281
int numentries = scandir(tempdir, &direntries, notdotentries,
2283
if (numentries > 0){
2284
for(int i = 0; i < numentries; i++){
2285
direntry = direntries[i];
2286
char *fullname = NULL;
2287
ret = asprintf(&fullname, "%s/%s", tempdir,
2290
perror_plus("asprintf");
2293
ret = remove(fullname);
2295
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2302
/* need to clean even if 0 because man page doesn't specify */
2304
if (numentries == -1){
2305
perror_plus("scandir");
2307
ret = rmdir(tempdir);
2308
if(ret == -1 and errno != ENOENT){
2309
perror_plus("rmdir");
2314
sigemptyset(&old_sigterm_action.sa_mask);
2315
old_sigterm_action.sa_handler = SIG_DFL;
2316
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2317
&old_sigterm_action,
2320
perror_plus("sigaction");
2323
ret = raise(signal_received);
2324
} while(ret != 0 and errno == EINTR);
2326
perror_plus("raise");
2329
TEMP_FAILURE_RETRY(pause());