1
/* -*- coding: utf-8 -*- */
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* 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",
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* "browse_callback", and parts of "main".
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* Copyright © 2008-2015 Teddy Hogeborn
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* Copyright © 2008-2015 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
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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* 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.
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@recompile.se>.
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/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
35
#endif /* not _LARGEFILE_SOURCE */
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#ifndef _FILE_OFFSET_BITS
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#define _FILE_OFFSET_BITS 64
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#endif /* not _FILE_OFFSET_BITS */
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
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#include <stdio.h> /* fprintf(), stderr, fwrite(),
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#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
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#include <stddef.h> /* NULL, size_t, ssize_t */
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#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
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strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
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sockaddr_in6, PF_INET6,
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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(),
60
#include <fcntl.h> /* open(), unlinkat() */
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
65
#include <errno.h> /* perror(), errno,
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program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
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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(),
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getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit(),
78
#include <arpa/inet.h> /* inet_pton(), htons() */
79
#include <iso646.h> /* not, or, and */
80
#include <argp.h> /* struct argp_option, error_t, struct
81
argp_state, struct argp,
82
argp_parse(), ARGP_KEY_ARG,
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ARGP_KEY_END, ARGP_ERR_UNKNOWN */
84
#include <signal.h> /* sigemptyset(), sigaddset(),
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sigaction(), SIGTERM, sig_atomic_t,
87
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
88
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
90
WEXITSTATUS(), WTERMSIG() */
91
#include <grp.h> /* setgroups() */
92
#include <argz.h> /* argz_add_sep(), argz_next(),
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argz_delete(), argz_append(),
94
argz_stringify(), argz_add(),
96
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
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EAI_SYSTEM, gai_strerror() */
100
#include <sys/klog.h> /* klogctl() */
101
#endif /* __linux__ */
104
/* All Avahi types, constants and functions
107
#include <avahi-core/core.h>
108
#include <avahi-core/lookup.h>
109
#include <avahi-core/log.h>
110
#include <avahi-common/simple-watch.h>
111
#include <avahi-common/malloc.h>
112
#include <avahi-common/error.h>
115
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
118
init_gnutls_session(),
120
#include <gnutls/openpgp.h>
121
/* gnutls_certificate_set_openpgp_key_file(),
122
GNUTLS_OPENPGP_FMT_BASE64 */
125
#include <gpgme.h> /* All GPGME types, constants and
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GPGME_PROTOCOL_OpenPGP,
131
#define BUFFER_SIZE 256
133
#define PATHDIR "/conf/conf.d/mandos"
134
#define SECKEY "seckey.txt"
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#define PUBKEY "pubkey.txt"
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#define HOOKDIR "/lib/mandos/network-hooks.d"
139
static const char mandos_protocol_version[] = "1";
140
const char *argp_program_version = "mandos-client " VERSION;
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const char *argp_program_bug_address = "<mandos@recompile.se>";
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static const char sys_class_net[] = "/sys/class/net";
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char *connect_to = NULL;
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const char *hookdir = HOOKDIR;
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/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
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AvahiIfIndex if_index;
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struct timespec last_seen;
160
/* Used for passing in values through the Avahi callback functions */
163
gnutls_certificate_credentials_t cred;
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unsigned int dh_bits;
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gnutls_dh_params_t dh_params;
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const char *priority;
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server *current_server;
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size_t interfaces_size;
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/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
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sig_atomic_t quit_now = 0;
177
int signal_received = 0;
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
182
fprintf(stderr, "Mandos plugin %s: ",
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program_invocation_short_name);
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
191
va_start (ap, format);
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
200
* bytes. "buffer_capacity" is how much is currently allocated,
201
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
204
size_t incbuffer(char **buffer, size_t buffer_length,
205
size_t buffer_capacity){
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
int old_errno = errno;
216
buffer_capacity += BUFFER_SIZE;
218
return buffer_capacity;
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
231
*new_server = (server){ .ip = strdup(ip),
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.if_index = if_index,
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
242
perror_plus("clock_gettime");
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
247
free((char *)(new_server->ip));
249
#pragma GCC diagnostic pop
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
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new_server->prev = new_server;
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*current_server = new_server;
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
278
gpgme_engine_info_t engine_info;
281
* Helper function to insert pub and seckey to the engine keyring.
283
bool import_key(const char * const filename){
286
gpgme_data_t pgp_data;
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
295
if(rc != GPG_ERR_NO_ERROR){
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
301
rc = gpgme_op_import(mc->ctx, pgp_data);
302
if(rc != GPG_ERR_NO_ERROR){
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
310
perror_plus("close");
312
gpgme_data_release(pgp_data);
317
fprintf_plus(stderr, "Initializing GPGME\n");
321
gpgme_check_version(NULL);
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
323
if(rc != GPG_ERR_NO_ERROR){
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
329
/* Set GPGME home directory for the OpenPGP engine only */
330
rc = gpgme_get_engine_info(&engine_info);
331
if(rc != GPG_ERR_NO_ERROR){
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
336
while(engine_info != NULL){
337
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
338
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
339
engine_info->file_name, tempdir);
342
engine_info = engine_info->next;
344
if(engine_info == NULL){
345
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
350
/* Create new GPGME "context" */
351
rc = gpgme_new(&(mc->ctx));
352
if(rc != GPG_ERR_NO_ERROR){
353
fprintf_plus(stderr, "Mandos plugin mandos-client: "
354
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
359
if(not import_key(pubkey) or not import_key(seckey)){
367
* Decrypt OpenPGP data.
368
* Returns -1 on error
370
__attribute__((nonnull, warn_unused_result))
371
static ssize_t pgp_packet_decrypt(const char *cryptotext,
375
gpgme_data_t dh_crypto, dh_plain;
378
size_t plaintext_capacity = 0;
379
ssize_t plaintext_length = 0;
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
385
/* Create new GPGME data buffer from memory cryptotext */
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
388
if(rc != GPG_ERR_NO_ERROR){
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
394
/* Create new empty GPGME data buffer for the plaintext */
395
rc = gpgme_data_new(&dh_plain);
396
if(rc != GPG_ERR_NO_ERROR){
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
400
gpgme_data_release(dh_crypto);
404
/* Decrypt data from the cryptotext data buffer to the plaintext
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
407
if(rc != GPG_ERR_NO_ERROR){
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
410
plaintext_length = -1;
412
gpgme_decrypt_result_t result;
413
result = gpgme_op_decrypt_result(mc->ctx);
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
421
if(result->file_name != NULL){
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
424
gpgme_recipient_t recipient;
425
recipient = result->recipients;
426
while(recipient != NULL){
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
434
recipient = recipient->next;
442
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
445
/* Seek back to the beginning of the GPGME plaintext data buffer */
446
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
447
perror_plus("gpgme_data_seek");
448
plaintext_length = -1;
454
plaintext_capacity = incbuffer(plaintext,
455
(size_t)plaintext_length,
457
if(plaintext_capacity == 0){
458
perror_plus("incbuffer");
459
plaintext_length = -1;
463
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
465
/* Print the data, if any */
471
perror_plus("gpgme_data_read");
472
plaintext_length = -1;
475
plaintext_length += ret;
479
fprintf_plus(stderr, "Decrypted password is: ");
480
for(ssize_t i = 0; i < plaintext_length; i++){
481
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
483
fprintf(stderr, "\n");
488
/* Delete the GPGME cryptotext data buffer */
489
gpgme_data_release(dh_crypto);
491
/* Delete the GPGME plaintext data buffer */
492
gpgme_data_release(dh_plain);
493
return plaintext_length;
496
__attribute__((warn_unused_result, const))
497
static const char *safe_string(const char *str){
503
__attribute__((warn_unused_result))
504
static const char *safer_gnutls_strerror(int value){
505
const char *ret = gnutls_strerror(value);
506
return safe_string(ret);
509
/* GnuTLS log function callback */
510
__attribute__((nonnull))
511
static void debuggnutls(__attribute__((unused)) int level,
513
fprintf_plus(stderr, "GnuTLS: %s", string);
516
__attribute__((nonnull, warn_unused_result))
517
static int init_gnutls_global(const char *pubkeyfilename,
518
const char *seckeyfilename,
524
fprintf_plus(stderr, "Initializing GnuTLS\n");
527
ret = gnutls_global_init();
528
if(ret != GNUTLS_E_SUCCESS){
529
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
530
safer_gnutls_strerror(ret));
535
/* "Use a log level over 10 to enable all debugging options."
538
gnutls_global_set_log_level(11);
539
gnutls_global_set_log_function(debuggnutls);
542
/* OpenPGP credentials */
543
ret = gnutls_certificate_allocate_credentials(&mc->cred);
544
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
546
safer_gnutls_strerror(ret));
547
gnutls_global_deinit();
552
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
553
" secret key %s as GnuTLS credentials\n",
558
ret = gnutls_certificate_set_openpgp_key_file
559
(mc->cred, pubkeyfilename, seckeyfilename,
560
GNUTLS_OPENPGP_FMT_BASE64);
561
if(ret != GNUTLS_E_SUCCESS){
563
"Error[%d] while reading the OpenPGP key pair ('%s',"
564
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
565
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
566
safer_gnutls_strerror(ret));
570
/* GnuTLS server initialization */
571
ret = gnutls_dh_params_init(&mc->dh_params);
572
if(ret != GNUTLS_E_SUCCESS){
573
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
574
" initialization: %s\n",
575
safer_gnutls_strerror(ret));
578
if(mc->dh_bits == 0){
579
/* Find out the optimal number of DH bits */
580
/* Try to read the private key file */
581
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
583
int secfile = open(seckeyfilename, O_RDONLY);
584
size_t buffer_capacity = 0;
586
buffer_capacity = incbuffer((char **)&buffer.data,
588
(size_t)buffer_capacity);
589
if(buffer_capacity == 0){
590
perror_plus("incbuffer");
595
ssize_t bytes_read = read(secfile, buffer.data + buffer.size,
601
/* check bytes_read for failure */
608
buffer.size += (unsigned int)bytes_read;
612
/* If successful, use buffer to parse private key */
613
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
614
if(buffer.data != NULL){
616
gnutls_openpgp_privkey_t privkey = NULL;
617
ret = gnutls_openpgp_privkey_init(&privkey);
618
if(ret != GNUTLS_E_SUCCESS){
619
fprintf_plus(stderr, "Error initializing OpenPGP key"
620
" structure: %s", safer_gnutls_strerror(ret));
624
ret = gnutls_openpgp_privkey_import(privkey, &buffer,
625
GNUTLS_OPENPGP_FMT_BASE64,
627
if(ret != GNUTLS_E_SUCCESS){
628
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
629
safer_gnutls_strerror(ret));
635
/* Use private key to suggest an appropriate sec_param */
636
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
637
gnutls_openpgp_privkey_deinit(privkey);
639
fprintf_plus(stderr, "This OpenPGP key implies using a"
640
" GnuTLS security parameter \"%s\".\n",
641
safe_string(gnutls_sec_param_get_name
647
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
648
/* Err on the side of caution */
649
sec_param = GNUTLS_SEC_PARAM_ULTRA;
651
fprintf_plus(stderr, "Falling back to security parameter"
653
safe_string(gnutls_sec_param_get_name
658
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
662
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
663
" implies %u DH bits; using that.\n",
664
safe_string(gnutls_sec_param_get_name
669
fprintf_plus(stderr, "Failed to get implied number of DH"
670
" bits for security parameter \"%s\"): %s\n",
671
safe_string(gnutls_sec_param_get_name(sec_param)),
672
safer_gnutls_strerror(ret));
676
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
679
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u bits):"
682
" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));
686
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
692
gnutls_certificate_free_credentials(mc->cred);
693
gnutls_global_deinit();
694
gnutls_dh_params_deinit(mc->dh_params);
698
__attribute__((nonnull, warn_unused_result))
699
static int init_gnutls_session(gnutls_session_t *session,
702
/* GnuTLS session creation */
704
ret = gnutls_init(session, GNUTLS_SERVER);
708
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
709
if(ret != GNUTLS_E_SUCCESS){
711
"Error in GnuTLS session initialization: %s\n",
712
safer_gnutls_strerror(ret));
718
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
720
gnutls_deinit(*session);
723
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
724
if(ret != GNUTLS_E_SUCCESS){
725
fprintf_plus(stderr, "Syntax error at: %s\n", err);
726
fprintf_plus(stderr, "GnuTLS error: %s\n",
727
safer_gnutls_strerror(ret));
728
gnutls_deinit(*session);
734
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
737
gnutls_deinit(*session);
740
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
741
if(ret != GNUTLS_E_SUCCESS){
742
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
743
safer_gnutls_strerror(ret));
744
gnutls_deinit(*session);
748
/* ignore client certificate if any. */
749
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
751
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
756
/* Avahi log function callback */
757
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
758
__attribute__((unused)) const char *txt){}
760
/* Set effective uid to 0, return errno */
761
__attribute__((warn_unused_result))
762
error_t raise_privileges(void){
763
error_t old_errno = errno;
764
error_t ret_errno = 0;
765
if(seteuid(0) == -1){
772
/* Set effective and real user ID to 0. Return errno. */
773
__attribute__((warn_unused_result))
774
error_t raise_privileges_permanently(void){
775
error_t old_errno = errno;
776
error_t ret_errno = raise_privileges();
788
/* Set effective user ID to unprivileged saved user ID */
789
__attribute__((warn_unused_result))
790
error_t lower_privileges(void){
791
error_t old_errno = errno;
792
error_t ret_errno = 0;
793
if(seteuid(uid) == -1){
800
/* Lower privileges permanently */
801
__attribute__((warn_unused_result))
802
error_t lower_privileges_permanently(void){
803
error_t old_errno = errno;
804
error_t ret_errno = 0;
805
if(setuid(uid) == -1){
812
/* Helper function to add_local_route() and delete_local_route() */
813
__attribute__((nonnull, warn_unused_result))
814
static bool add_delete_local_route(const bool add,
816
AvahiIfIndex if_index){
818
char helper[] = "mandos-client-iprouteadddel";
819
char add_arg[] = "add";
820
char delete_arg[] = "delete";
821
char debug_flag[] = "--debug";
822
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
823
if(pluginhelperdir == NULL){
825
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
826
" variable not set; cannot run helper\n");
831
char interface[IF_NAMESIZE];
832
if(if_indextoname((unsigned int)if_index, interface) == NULL){
833
perror_plus("if_indextoname");
837
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
839
perror_plus("open(\"/dev/null\", O_RDONLY)");
845
/* Raise privileges */
846
errno = raise_privileges_permanently();
848
perror_plus("Failed to raise privileges");
849
/* _exit(EX_NOPERM); */
855
perror_plus("setgid");
858
/* Reset supplementary groups */
860
ret = setgroups(0, NULL);
862
perror_plus("setgroups");
866
ret = dup2(devnull, STDIN_FILENO);
868
perror_plus("dup2(devnull, STDIN_FILENO)");
871
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
873
perror_plus("close");
876
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
878
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
881
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
886
if(helperdir_fd == -1){
888
_exit(EX_UNAVAILABLE);
890
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
893
perror_plus("openat");
894
_exit(EX_UNAVAILABLE);
896
TEMP_FAILURE_RETRY(close(helperdir_fd));
898
#pragma GCC diagnostic push
899
#pragma GCC diagnostic ignored "-Wcast-qual"
901
if(fexecve(helper_fd, (char *const [])
902
{ helper, add ? add_arg : delete_arg, (char *)address,
903
interface, debug ? debug_flag : NULL, NULL },
906
#pragma GCC diagnostic pop
908
perror_plus("fexecve");
920
pret = waitpid(pid, &status, 0);
921
if(pret == -1 and errno == EINTR and quit_now){
922
int errno_raising = 0;
923
if((errno = raise_privileges()) != 0){
924
errno_raising = errno;
925
perror_plus("Failed to raise privileges in order to"
926
" kill helper program");
928
if(kill(pid, SIGTERM) == -1){
931
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
932
perror_plus("Failed to lower privileges after killing"
937
} while(pret == -1 and errno == EINTR);
939
perror_plus("waitpid");
942
if(WIFEXITED(status)){
943
if(WEXITSTATUS(status) != 0){
944
fprintf_plus(stderr, "Error: iprouteadddel exited"
945
" with status %d\n", WEXITSTATUS(status));
950
if(WIFSIGNALED(status)){
951
fprintf_plus(stderr, "Error: iprouteadddel died by"
952
" signal %d\n", WTERMSIG(status));
955
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
959
__attribute__((nonnull, warn_unused_result))
960
static bool add_local_route(const char *address,
961
AvahiIfIndex if_index){
963
fprintf_plus(stderr, "Adding route to %s\n", address);
965
return add_delete_local_route(true, address, if_index);
968
__attribute__((nonnull, warn_unused_result))
969
static bool delete_local_route(const char *address,
970
AvahiIfIndex if_index){
972
fprintf_plus(stderr, "Removing route to %s\n", address);
974
return add_delete_local_route(false, address, if_index);
977
/* Called when a Mandos server is found */
978
__attribute__((nonnull, warn_unused_result))
979
static int start_mandos_communication(const char *ip, in_port_t port,
980
AvahiIfIndex if_index,
981
int af, mandos_context *mc){
982
int ret, tcp_sd = -1;
984
struct sockaddr_storage to;
986
char *decrypted_buffer = NULL;
987
size_t buffer_length = 0;
988
size_t buffer_capacity = 0;
991
gnutls_session_t session;
992
int pf; /* Protocol family */
993
bool route_added = false;
1010
fprintf_plus(stderr, "Bad address family: %d\n", af);
1015
/* If the interface is specified and we have a list of interfaces */
1016
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1017
/* Check if the interface is one of the interfaces we are using */
1020
char *interface = NULL;
1021
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1023
if(if_nametoindex(interface) == (unsigned int)if_index){
1030
/* This interface does not match any in the list, so we don't
1031
connect to the server */
1033
char interface[IF_NAMESIZE];
1034
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1035
perror_plus("if_indextoname");
1037
fprintf_plus(stderr, "Skipping server on non-used interface"
1039
if_indextoname((unsigned int)if_index,
1047
ret = init_gnutls_session(&session, mc);
1053
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1054
PRIuMAX "\n", ip, (uintmax_t)port);
1057
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1060
perror_plus("socket");
1070
memset(&to, 0, sizeof(to));
1072
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
1073
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
1075
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
1076
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
1080
perror_plus("inet_pton");
1086
fprintf_plus(stderr, "Bad address: %s\n", ip);
1091
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1092
if(IN6_IS_ADDR_LINKLOCAL
1093
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1094
if(if_index == AVAHI_IF_UNSPEC){
1095
fprintf_plus(stderr, "An IPv6 link-local address is"
1096
" incomplete without a network interface\n");
1100
/* Set the network interface number as scope */
1101
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1104
((struct sockaddr_in *)&to)->sin_port = htons(port);
1113
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1114
char interface[IF_NAMESIZE];
1115
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1116
perror_plus("if_indextoname");
1118
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1119
"\n", ip, interface, (uintmax_t)port);
1122
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1123
ip, (uintmax_t)port);
1125
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1126
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1128
ret = getnameinfo((struct sockaddr *)&to,
1129
sizeof(struct sockaddr_in6),
1130
addrstr, sizeof(addrstr), NULL, 0,
1133
ret = getnameinfo((struct sockaddr *)&to,
1134
sizeof(struct sockaddr_in),
1135
addrstr, sizeof(addrstr), NULL, 0,
1138
if(ret == EAI_SYSTEM){
1139
perror_plus("getnameinfo");
1140
} else if(ret != 0) {
1141
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1142
} else if(strcmp(addrstr, ip) != 0){
1143
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1154
ret = connect(tcp_sd, (struct sockaddr *)&to,
1155
sizeof(struct sockaddr_in6));
1157
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1158
sizeof(struct sockaddr_in));
1161
if(errno == ENETUNREACH
1162
and if_index != AVAHI_IF_UNSPEC
1163
and connect_to == NULL
1164
and not route_added and
1165
((af == AF_INET6 and not
1166
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1168
or (af == AF_INET and
1169
/* Not a a IPv4LL address */
1170
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1171
& 0xFFFF0000L) != 0xA9FE0000L))){
1172
/* Work around Avahi bug - Avahi does not announce link-local
1173
addresses if it has a global address, so local hosts with
1174
*only* a link-local address (e.g. Mandos clients) cannot
1175
connect to a Mandos server announced by Avahi on a server
1176
host with a global address. Work around this by retrying
1177
with an explicit route added with the server's address.
1179
Avahi bug reference:
1180
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1181
https://bugs.debian.org/587961
1184
fprintf_plus(stderr, "Mandos server unreachable, trying"
1188
route_added = add_local_route(ip, if_index);
1194
if(errno != ECONNREFUSED or debug){
1196
perror_plus("connect");
1209
const char *out = mandos_protocol_version;
1212
size_t out_size = strlen(out);
1213
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1214
out_size - written));
1217
perror_plus("write");
1221
written += (size_t)ret;
1222
if(written < out_size){
1225
if(out == mandos_protocol_version){
1240
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1248
/* This casting via intptr_t is to eliminate warning about casting
1249
an int to a pointer type. This is exactly how the GnuTLS Guile
1250
function "set-session-transport-fd!" does it. */
1251
gnutls_transport_set_ptr(session,
1252
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1260
ret = gnutls_handshake(session);
1265
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1267
if(ret != GNUTLS_E_SUCCESS){
1269
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
1276
/* Read OpenPGP packet that contains the wanted password */
1279
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
1290
buffer_capacity = incbuffer(&buffer, buffer_length,
1292
if(buffer_capacity == 0){
1294
perror_plus("incbuffer");
1304
sret = gnutls_record_recv(session, buffer+buffer_length,
1311
case GNUTLS_E_INTERRUPTED:
1312
case GNUTLS_E_AGAIN:
1314
case GNUTLS_E_REHANDSHAKE:
1316
ret = gnutls_handshake(session);
1322
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1324
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
1332
fprintf_plus(stderr, "Unknown error while reading data from"
1333
" encrypted session with Mandos server\n");
1334
gnutls_bye(session, GNUTLS_SHUT_RDWR);
1339
buffer_length += (size_t) sret;
1344
fprintf_plus(stderr, "Closing TLS session\n");
1353
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1358
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1360
if(buffer_length > 0){
1361
ssize_t decrypted_buffer_size;
1362
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1363
&decrypted_buffer, mc);
1364
if(decrypted_buffer_size >= 0){
1367
while(written < (size_t) decrypted_buffer_size){
1373
ret = (int)fwrite(decrypted_buffer + written, 1,
1374
(size_t)decrypted_buffer_size - written,
1376
if(ret == 0 and ferror(stdout)){
1379
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
1385
written += (size_t)ret;
1391
/* Shutdown procedure */
1396
if(not delete_local_route(ip, if_index)){
1397
fprintf_plus(stderr, "Failed to delete local route to %s on"
1398
" interface %d", ip, if_index);
1402
free(decrypted_buffer);
1405
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1411
perror_plus("close");
1413
gnutls_deinit(session);
1423
__attribute__((nonnull))
1424
static void resolve_callback(AvahiSServiceResolver *r,
1425
AvahiIfIndex interface,
1426
AvahiProtocol proto,
1427
AvahiResolverEvent event,
1431
const char *host_name,
1432
const AvahiAddress *address,
1434
AVAHI_GCC_UNUSED AvahiStringList *txt,
1435
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1442
/* Called whenever a service has been resolved successfully or
1446
avahi_s_service_resolver_free(r);
1452
case AVAHI_RESOLVER_FAILURE:
1453
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1454
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1456
avahi_strerror(avahi_server_errno
1457
(((mandos_context*)mc)->server)));
1460
case AVAHI_RESOLVER_FOUND:
1462
char ip[AVAHI_ADDRESS_STR_MAX];
1463
avahi_address_snprint(ip, sizeof(ip), address);
1465
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1466
PRIdMAX ") on port %" PRIu16 "\n", name,
1467
host_name, ip, (intmax_t)interface, port);
1469
int ret = start_mandos_communication(ip, (in_port_t)port,
1471
avahi_proto_to_af(proto),
1474
avahi_simple_poll_quit(simple_poll);
1476
if(not add_server(ip, (in_port_t)port, interface,
1477
avahi_proto_to_af(proto),
1478
&((mandos_context*)mc)->current_server)){
1479
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1485
avahi_s_service_resolver_free(r);
1488
static void browse_callback(AvahiSServiceBrowser *b,
1489
AvahiIfIndex interface,
1490
AvahiProtocol protocol,
1491
AvahiBrowserEvent event,
1495
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1502
/* Called whenever a new services becomes available on the LAN or
1503
is removed from the LAN */
1511
case AVAHI_BROWSER_FAILURE:
1513
fprintf_plus(stderr, "(Avahi browser) %s\n",
1514
avahi_strerror(avahi_server_errno
1515
(((mandos_context*)mc)->server)));
1516
avahi_simple_poll_quit(simple_poll);
1519
case AVAHI_BROWSER_NEW:
1520
/* We ignore the returned Avahi resolver object. In the callback
1521
function we free it. If the Avahi server is terminated before
1522
the callback function is called the Avahi server will free the
1525
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1526
interface, protocol, name, type,
1527
domain, protocol, 0,
1528
resolve_callback, mc) == NULL)
1529
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1531
avahi_strerror(avahi_server_errno
1532
(((mandos_context*)mc)->server)));
1535
case AVAHI_BROWSER_REMOVE:
1538
case AVAHI_BROWSER_ALL_FOR_NOW:
1539
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1541
fprintf_plus(stderr, "No Mandos server found, still"
1548
/* Signal handler that stops main loop after SIGTERM */
1549
static void handle_sigterm(int sig){
1554
signal_received = sig;
1555
int old_errno = errno;
1556
/* set main loop to exit */
1557
if(simple_poll != NULL){
1558
avahi_simple_poll_quit(simple_poll);
1563
__attribute__((nonnull, warn_unused_result))
1564
bool get_flags(const char *ifname, struct ifreq *ifr){
1568
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1571
perror_plus("socket");
1575
strcpy(ifr->ifr_name, ifname);
1576
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1580
perror_plus("ioctl SIOCGIFFLAGS");
1588
__attribute__((nonnull, warn_unused_result))
1589
bool good_flags(const char *ifname, const struct ifreq *ifr){
1591
/* Reject the loopback device */
1592
if(ifr->ifr_flags & IFF_LOOPBACK){
1594
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1599
/* Accept point-to-point devices only if connect_to is specified */
1600
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1602
fprintf_plus(stderr, "Accepting point-to-point interface"
1603
" \"%s\"\n", ifname);
1607
/* Otherwise, reject non-broadcast-capable devices */
1608
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1610
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1611
" \"%s\"\n", ifname);
1615
/* Reject non-ARP interfaces (including dummy interfaces) */
1616
if(ifr->ifr_flags & IFF_NOARP){
1618
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1624
/* Accept this device */
1626
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1632
* This function determines if a directory entry in /sys/class/net
1633
* corresponds to an acceptable network device.
1634
* (This function is passed to scandir(3) as a filter function.)
1636
__attribute__((nonnull, warn_unused_result))
1637
int good_interface(const struct dirent *if_entry){
1638
if(if_entry->d_name[0] == '.'){
1643
if(not get_flags(if_entry->d_name, &ifr)){
1645
fprintf_plus(stderr, "Failed to get flags for interface "
1646
"\"%s\"\n", if_entry->d_name);
1651
if(not good_flags(if_entry->d_name, &ifr)){
1658
* This function determines if a network interface is up.
1660
__attribute__((nonnull, warn_unused_result))
1661
bool interface_is_up(const char *interface){
1663
if(not get_flags(interface, &ifr)){
1665
fprintf_plus(stderr, "Failed to get flags for interface "
1666
"\"%s\"\n", interface);
1671
return (bool)(ifr.ifr_flags & IFF_UP);
1675
* This function determines if a network interface is running
1677
__attribute__((nonnull, warn_unused_result))
1678
bool interface_is_running(const char *interface){
1680
if(not get_flags(interface, &ifr)){
1682
fprintf_plus(stderr, "Failed to get flags for interface "
1683
"\"%s\"\n", interface);
1688
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1691
__attribute__((nonnull, pure, warn_unused_result))
1692
int notdotentries(const struct dirent *direntry){
1693
/* Skip "." and ".." */
1694
if(direntry->d_name[0] == '.'
1695
and (direntry->d_name[1] == '\0'
1696
or (direntry->d_name[1] == '.'
1697
and direntry->d_name[2] == '\0'))){
1703
/* Is this directory entry a runnable program? */
1704
__attribute__((nonnull, warn_unused_result))
1705
int runnable_hook(const struct dirent *direntry){
1710
if((direntry->d_name)[0] == '\0'){
1715
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1716
"abcdefghijklmnopqrstuvwxyz"
1719
if((direntry->d_name)[sret] != '\0'){
1720
/* Contains non-allowed characters */
1722
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1728
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1731
perror_plus("Could not stat hook");
1735
if(not (S_ISREG(st.st_mode))){
1736
/* Not a regular file */
1738
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1743
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1744
/* Not executable */
1746
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1752
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1758
__attribute__((nonnull, warn_unused_result))
1759
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1760
mandos_context *mc){
1762
struct timespec now;
1763
struct timespec waited_time;
1764
intmax_t block_time;
1767
if(mc->current_server == NULL){
1769
fprintf_plus(stderr, "Wait until first server is found."
1772
ret = avahi_simple_poll_iterate(s, -1);
1775
fprintf_plus(stderr, "Check current_server if we should run"
1778
/* the current time */
1779
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1781
perror_plus("clock_gettime");
1784
/* Calculating in ms how long time between now and server
1785
who we visted longest time ago. Now - last seen. */
1786
waited_time.tv_sec = (now.tv_sec
1787
- mc->current_server->last_seen.tv_sec);
1788
waited_time.tv_nsec = (now.tv_nsec
1789
- mc->current_server->last_seen.tv_nsec);
1790
/* total time is 10s/10,000ms.
1791
Converting to s from ms by dividing by 1,000,
1792
and ns to ms by dividing by 1,000,000. */
1793
block_time = ((retry_interval
1794
- ((intmax_t)waited_time.tv_sec * 1000))
1795
- ((intmax_t)waited_time.tv_nsec / 1000000));
1798
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1802
if(block_time <= 0){
1803
ret = start_mandos_communication(mc->current_server->ip,
1804
mc->current_server->port,
1805
mc->current_server->if_index,
1806
mc->current_server->af, mc);
1808
avahi_simple_poll_quit(s);
1811
ret = clock_gettime(CLOCK_MONOTONIC,
1812
&mc->current_server->last_seen);
1814
perror_plus("clock_gettime");
1817
mc->current_server = mc->current_server->next;
1818
block_time = 0; /* Call avahi to find new Mandos
1819
servers, but don't block */
1822
ret = avahi_simple_poll_iterate(s, (int)block_time);
1825
if(ret > 0 or errno != EINTR){
1826
return (ret != 1) ? ret : 0;
1832
__attribute__((nonnull))
1833
void run_network_hooks(const char *mode, const char *interface,
1835
struct dirent **direntries = NULL;
1836
if(hookdir_fd == -1){
1837
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1839
if(hookdir_fd == -1){
1840
if(errno == ENOENT){
1842
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1843
" found\n", hookdir);
1846
perror_plus("open");
1852
#if __GLIBC_PREREQ(2, 15)
1853
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1854
runnable_hook, alphasort);
1855
#else /* not __GLIBC_PREREQ(2, 15) */
1856
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1858
#endif /* not __GLIBC_PREREQ(2, 15) */
1859
#else /* not __GLIBC__ */
1860
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1862
#endif /* not __GLIBC__ */
1864
perror_plus("scandir");
1867
struct dirent *direntry;
1869
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1871
perror_plus("open(\"/dev/null\", O_RDONLY)");
1874
for(int i = 0; i < numhooks; i++){
1875
direntry = direntries[i];
1877
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1880
pid_t hook_pid = fork();
1883
/* Raise privileges */
1884
errno = raise_privileges_permanently();
1886
perror_plus("Failed to raise privileges");
1893
perror_plus("setgid");
1896
/* Reset supplementary groups */
1898
ret = setgroups(0, NULL);
1900
perror_plus("setgroups");
1903
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1905
perror_plus("setenv");
1908
ret = setenv("DEVICE", interface, 1);
1910
perror_plus("setenv");
1913
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1915
perror_plus("setenv");
1918
ret = setenv("MODE", mode, 1);
1920
perror_plus("setenv");
1924
ret = asprintf(&delaystring, "%f", (double)delay);
1926
perror_plus("asprintf");
1929
ret = setenv("DELAY", delaystring, 1);
1932
perror_plus("setenv");
1936
if(connect_to != NULL){
1937
ret = setenv("CONNECT", connect_to, 1);
1939
perror_plus("setenv");
1943
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
1947
perror_plus("openat");
1948
_exit(EXIT_FAILURE);
1950
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1951
perror_plus("close");
1952
_exit(EXIT_FAILURE);
1954
ret = dup2(devnull, STDIN_FILENO);
1956
perror_plus("dup2(devnull, STDIN_FILENO)");
1959
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
1961
perror_plus("close");
1964
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1966
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1969
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1971
perror_plus("fexecve");
1972
_exit(EXIT_FAILURE);
1976
perror_plus("fork");
1981
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1982
perror_plus("waitpid");
1986
if(WIFEXITED(status)){
1987
if(WEXITSTATUS(status) != 0){
1988
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1989
" with status %d\n", direntry->d_name,
1990
WEXITSTATUS(status));
1994
} else if(WIFSIGNALED(status)){
1995
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1996
" signal %d\n", direntry->d_name,
2001
fprintf_plus(stderr, "Warning: network hook \"%s\""
2002
" crashed\n", direntry->d_name);
2008
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2014
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2015
perror_plus("close");
2022
__attribute__((nonnull, warn_unused_result))
2023
error_t bring_up_interface(const char *const interface,
2025
error_t old_errno = errno;
2027
struct ifreq network;
2028
unsigned int if_index = if_nametoindex(interface);
2030
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2040
if(not interface_is_up(interface)){
2041
error_t ret_errno = 0, ioctl_errno = 0;
2042
if(not get_flags(interface, &network)){
2044
fprintf_plus(stderr, "Failed to get flags for interface "
2045
"\"%s\"\n", interface);
2049
network.ifr_flags |= IFF_UP; /* set flag */
2051
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2054
perror_plus("socket");
2060
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2062
perror_plus("close");
2069
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2073
/* Raise privileges */
2074
ret_errno = raise_privileges();
2077
perror_plus("Failed to raise privileges");
2082
bool restore_loglevel = false;
2084
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2085
messages about the network interface to mess up the prompt */
2086
ret_linux = klogctl(8, NULL, 5);
2087
if(ret_linux == -1){
2088
perror_plus("klogctl");
2090
restore_loglevel = true;
2093
#endif /* __linux__ */
2094
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2095
ioctl_errno = errno;
2097
if(restore_loglevel){
2098
ret_linux = klogctl(7, NULL, 0);
2099
if(ret_linux == -1){
2100
perror_plus("klogctl");
2103
#endif /* __linux__ */
2105
/* If raise_privileges() succeeded above */
2107
/* Lower privileges */
2108
ret_errno = lower_privileges();
2111
perror_plus("Failed to lower privileges");
2115
/* Close the socket */
2116
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2118
perror_plus("close");
2121
if(ret_setflags == -1){
2122
errno = ioctl_errno;
2123
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2128
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2132
/* Sleep checking until interface is running.
2133
Check every 0.25s, up to total time of delay */
2134
for(int i=0; i < delay * 4; i++){
2135
if(interface_is_running(interface)){
2138
struct timespec sleeptime = { .tv_nsec = 250000000 };
2139
ret = nanosleep(&sleeptime, NULL);
2140
if(ret == -1 and errno != EINTR){
2141
perror_plus("nanosleep");
2149
__attribute__((nonnull, warn_unused_result))
2150
error_t take_down_interface(const char *const interface){
2151
error_t old_errno = errno;
2152
struct ifreq network;
2153
unsigned int if_index = if_nametoindex(interface);
2155
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2159
if(interface_is_up(interface)){
2160
error_t ret_errno = 0, ioctl_errno = 0;
2161
if(not get_flags(interface, &network) and debug){
2163
fprintf_plus(stderr, "Failed to get flags for interface "
2164
"\"%s\"\n", interface);
2168
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2170
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2173
perror_plus("socket");
2179
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2183
/* Raise privileges */
2184
ret_errno = raise_privileges();
2187
perror_plus("Failed to raise privileges");
2190
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2191
ioctl_errno = errno;
2193
/* If raise_privileges() succeeded above */
2195
/* Lower privileges */
2196
ret_errno = lower_privileges();
2199
perror_plus("Failed to lower privileges");
2203
/* Close the socket */
2204
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
2206
perror_plus("close");
2209
if(ret_setflags == -1){
2210
errno = ioctl_errno;
2211
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2216
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
2224
int main(int argc, char *argv[]){
2225
mandos_context mc = { .server = NULL, .dh_bits = 0,
2226
.priority = "SECURE256:!CTYPE-X.509:"
2227
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
2228
.interfaces = NULL, .interfaces_size = 0 };
2229
AvahiSServiceBrowser *sb = NULL;
2234
int exitcode = EXIT_SUCCESS;
2235
char *interfaces_to_take_down = NULL;
2236
size_t interfaces_to_take_down_size = 0;
2237
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2238
char old_tempdir[] = "/tmp/mandosXXXXXX";
2239
char *tempdir = NULL;
2240
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2241
const char *seckey = PATHDIR "/" SECKEY;
2242
const char *pubkey = PATHDIR "/" PUBKEY;
2243
char *interfaces_hooks = NULL;
2245
bool gnutls_initialized = false;
2246
bool gpgme_initialized = false;
2248
double retry_interval = 10; /* 10s between trying a server and
2249
retrying the same server again */
2251
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2252
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2257
/* Lower any group privileges we might have, just to be safe */
2261
perror_plus("setgid");
2264
/* Lower user privileges (temporarily) */
2268
perror_plus("seteuid");
2276
struct argp_option options[] = {
2277
{ .name = "debug", .key = 128,
2278
.doc = "Debug mode", .group = 3 },
2279
{ .name = "connect", .key = 'c',
2280
.arg = "ADDRESS:PORT",
2281
.doc = "Connect directly to a specific Mandos server",
2283
{ .name = "interface", .key = 'i',
2285
.doc = "Network interface that will be used to search for"
2288
{ .name = "seckey", .key = 's',
2290
.doc = "OpenPGP secret key file base name",
2292
{ .name = "pubkey", .key = 'p',
2294
.doc = "OpenPGP public key file base name",
2296
{ .name = "dh-bits", .key = 129,
2298
.doc = "Bit length of the prime number used in the"
2299
" Diffie-Hellman key exchange",
2301
{ .name = "priority", .key = 130,
2303
.doc = "GnuTLS priority string for the TLS handshake",
2305
{ .name = "delay", .key = 131,
2307
.doc = "Maximum delay to wait for interface startup",
2309
{ .name = "retry", .key = 132,
2311
.doc = "Retry interval used when denied by the Mandos server",
2313
{ .name = "network-hook-dir", .key = 133,
2315
.doc = "Directory where network hooks are located",
2318
* These reproduce what we would get without ARGP_NO_HELP
2320
{ .name = "help", .key = '?',
2321
.doc = "Give this help list", .group = -1 },
2322
{ .name = "usage", .key = -3,
2323
.doc = "Give a short usage message", .group = -1 },
2324
{ .name = "version", .key = 'V',
2325
.doc = "Print program version", .group = -1 },
2329
error_t parse_opt(int key, char *arg,
2330
struct argp_state *state){
2333
case 128: /* --debug */
2336
case 'c': /* --connect */
2339
case 'i': /* --interface */
2340
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2343
argp_error(state, "%s", strerror(ret_errno));
2346
case 's': /* --seckey */
2349
case 'p': /* --pubkey */
2352
case 129: /* --dh-bits */
2354
tmpmax = strtoimax(arg, &tmp, 10);
2355
if(errno != 0 or tmp == arg or *tmp != '\0'
2356
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2357
argp_error(state, "Bad number of DH bits");
2359
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2361
case 130: /* --priority */
2364
case 131: /* --delay */
2366
delay = strtof(arg, &tmp);
2367
if(errno != 0 or tmp == arg or *tmp != '\0'){
2368
argp_error(state, "Bad delay");
2370
case 132: /* --retry */
2372
retry_interval = strtod(arg, &tmp);
2373
if(errno != 0 or tmp == arg or *tmp != '\0'
2374
or (retry_interval * 1000) > INT_MAX
2375
or retry_interval < 0){
2376
argp_error(state, "Bad retry interval");
2379
case 133: /* --network-hook-dir */
2383
* These reproduce what we would get without ARGP_NO_HELP
2385
case '?': /* --help */
2386
argp_state_help(state, state->out_stream,
2387
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2388
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2389
case -3: /* --usage */
2390
argp_state_help(state, state->out_stream,
2391
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2392
case 'V': /* --version */
2393
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2394
exit(argp_err_exit_status);
2397
return ARGP_ERR_UNKNOWN;
2402
struct argp argp = { .options = options, .parser = parse_opt,
2404
.doc = "Mandos client -- Get and decrypt"
2405
" passwords from a Mandos server" };
2406
ret = argp_parse(&argp, argc, argv,
2407
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2414
perror_plus("argp_parse");
2415
exitcode = EX_OSERR;
2418
exitcode = EX_USAGE;
2424
/* Work around Debian bug #633582:
2425
<http://bugs.debian.org/633582> */
2427
/* Re-raise privileges */
2428
ret_errno = raise_privileges();
2431
perror_plus("Failed to raise privileges");
2435
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2436
int seckey_fd = open(seckey, O_RDONLY);
2437
if(seckey_fd == -1){
2438
perror_plus("open");
2440
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2442
perror_plus("fstat");
2444
if(S_ISREG(st.st_mode)
2445
and st.st_uid == 0 and st.st_gid == 0){
2446
ret = fchown(seckey_fd, uid, gid);
2448
perror_plus("fchown");
2452
TEMP_FAILURE_RETRY(close(seckey_fd));
2456
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2457
int pubkey_fd = open(pubkey, O_RDONLY);
2458
if(pubkey_fd == -1){
2459
perror_plus("open");
2461
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2463
perror_plus("fstat");
2465
if(S_ISREG(st.st_mode)
2466
and st.st_uid == 0 and st.st_gid == 0){
2467
ret = fchown(pubkey_fd, uid, gid);
2469
perror_plus("fchown");
2473
TEMP_FAILURE_RETRY(close(pubkey_fd));
2477
/* Lower privileges */
2478
ret_errno = lower_privileges();
2481
perror_plus("Failed to lower privileges");
2486
/* Remove invalid interface names (except "none") */
2488
char *interface = NULL;
2489
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2491
if(strcmp(interface, "none") != 0
2492
and if_nametoindex(interface) == 0){
2493
if(interface[0] != '\0'){
2494
fprintf_plus(stderr, "Not using nonexisting interface"
2495
" \"%s\"\n", interface);
2497
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2503
/* Run network hooks */
2505
if(mc.interfaces != NULL){
2506
interfaces_hooks = malloc(mc.interfaces_size);
2507
if(interfaces_hooks == NULL){
2508
perror_plus("malloc");
2511
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2512
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2514
run_network_hooks("start", interfaces_hooks != NULL ?
2515
interfaces_hooks : "", delay);
2519
avahi_set_log_function(empty_log);
2522
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2523
from the signal handler */
2524
/* Initialize the pseudo-RNG for Avahi */
2525
srand((unsigned int) time(NULL));
2526
simple_poll = avahi_simple_poll_new();
2527
if(simple_poll == NULL){
2528
fprintf_plus(stderr,
2529
"Avahi: Failed to create simple poll object.\n");
2530
exitcode = EX_UNAVAILABLE;
2534
sigemptyset(&sigterm_action.sa_mask);
2535
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2537
perror_plus("sigaddset");
2538
exitcode = EX_OSERR;
2541
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2543
perror_plus("sigaddset");
2544
exitcode = EX_OSERR;
2547
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2549
perror_plus("sigaddset");
2550
exitcode = EX_OSERR;
2553
/* Need to check if the handler is SIG_IGN before handling:
2554
| [[info:libc:Initial Signal Actions]] |
2555
| [[info:libc:Basic Signal Handling]] |
2557
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2559
perror_plus("sigaction");
2562
if(old_sigterm_action.sa_handler != SIG_IGN){
2563
ret = sigaction(SIGINT, &sigterm_action, NULL);
2565
perror_plus("sigaction");
2566
exitcode = EX_OSERR;
2570
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2572
perror_plus("sigaction");
2575
if(old_sigterm_action.sa_handler != SIG_IGN){
2576
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2578
perror_plus("sigaction");
2579
exitcode = EX_OSERR;
2583
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2585
perror_plus("sigaction");
2588
if(old_sigterm_action.sa_handler != SIG_IGN){
2589
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2591
perror_plus("sigaction");
2592
exitcode = EX_OSERR;
2597
/* If no interfaces were specified, make a list */
2598
if(mc.interfaces == NULL){
2599
struct dirent **direntries = NULL;
2600
/* Look for any good interfaces */
2601
ret = scandir(sys_class_net, &direntries, good_interface,
2604
/* Add all found interfaces to interfaces list */
2605
for(int i = 0; i < ret; ++i){
2606
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2607
direntries[i]->d_name);
2610
perror_plus("argz_add");
2611
free(direntries[i]);
2615
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2616
direntries[i]->d_name);
2618
free(direntries[i]);
2625
fprintf_plus(stderr, "Could not find a network interface\n");
2626
exitcode = EXIT_FAILURE;
2631
/* Bring up interfaces which are down, and remove any "none"s */
2633
char *interface = NULL;
2634
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2636
/* If interface name is "none", stop bringing up interfaces.
2637
Also remove all instances of "none" from the list */
2638
if(strcmp(interface, "none") == 0){
2639
argz_delete(&mc.interfaces, &mc.interfaces_size,
2642
while((interface = argz_next(mc.interfaces,
2643
mc.interfaces_size, interface))){
2644
if(strcmp(interface, "none") == 0){
2645
argz_delete(&mc.interfaces, &mc.interfaces_size,
2652
bool interface_was_up = interface_is_up(interface);
2653
errno = bring_up_interface(interface, delay);
2654
if(not interface_was_up){
2656
perror_plus("Failed to bring up interface");
2658
errno = argz_add(&interfaces_to_take_down,
2659
&interfaces_to_take_down_size,
2662
perror_plus("argz_add");
2667
if(debug and (interfaces_to_take_down == NULL)){
2668
fprintf_plus(stderr, "No interfaces were brought up\n");
2672
/* If we only got one interface, explicitly use only that one */
2673
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2675
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2678
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2685
ret = init_gnutls_global(pubkey, seckey, &mc);
2687
fprintf_plus(stderr, "init_gnutls_global failed\n");
2688
exitcode = EX_UNAVAILABLE;
2691
gnutls_initialized = true;
2698
/* Try /run/tmp before /tmp */
2699
tempdir = mkdtemp(run_tempdir);
2700
if(tempdir == NULL and errno == ENOENT){
2702
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2703
run_tempdir, old_tempdir);
2705
tempdir = mkdtemp(old_tempdir);
2707
if(tempdir == NULL){
2708
perror_plus("mkdtemp");
2716
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2717
fprintf_plus(stderr, "init_gpgme failed\n");
2718
exitcode = EX_UNAVAILABLE;
2721
gpgme_initialized = true;
2728
if(connect_to != NULL){
2729
/* Connect directly, do not use Zeroconf */
2730
/* (Mainly meant for debugging) */
2731
char *address = strrchr(connect_to, ':');
2733
if(address == NULL){
2734
fprintf_plus(stderr, "No colon in address\n");
2735
exitcode = EX_USAGE;
2745
tmpmax = strtoimax(address+1, &tmp, 10);
2746
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2747
or tmpmax != (in_port_t)tmpmax){
2748
fprintf_plus(stderr, "Bad port number\n");
2749
exitcode = EX_USAGE;
2757
port = (in_port_t)tmpmax;
2759
/* Colon in address indicates IPv6 */
2761
if(strchr(connect_to, ':') != NULL){
2763
/* Accept [] around IPv6 address - see RFC 5952 */
2764
if(connect_to[0] == '[' and address[-1] == ']')
2772
address = connect_to;
2778
while(not quit_now){
2779
ret = start_mandos_communication(address, port, if_index, af,
2781
if(quit_now or ret == 0){
2785
fprintf_plus(stderr, "Retrying in %d seconds\n",
2786
(int)retry_interval);
2788
sleep((unsigned int)retry_interval);
2792
exitcode = EXIT_SUCCESS;
2803
AvahiServerConfig config;
2804
/* Do not publish any local Zeroconf records */
2805
avahi_server_config_init(&config);
2806
config.publish_hinfo = 0;
2807
config.publish_addresses = 0;
2808
config.publish_workstation = 0;
2809
config.publish_domain = 0;
2811
/* Allocate a new server */
2812
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2813
&config, NULL, NULL, &ret_errno);
2815
/* Free the Avahi configuration data */
2816
avahi_server_config_free(&config);
2819
/* Check if creating the Avahi server object succeeded */
2820
if(mc.server == NULL){
2821
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2822
avahi_strerror(ret_errno));
2823
exitcode = EX_UNAVAILABLE;
2831
/* Create the Avahi service browser */
2832
sb = avahi_s_service_browser_new(mc.server, if_index,
2833
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2834
NULL, 0, browse_callback,
2837
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2838
avahi_strerror(avahi_server_errno(mc.server)));
2839
exitcode = EX_UNAVAILABLE;
2847
/* Run the main loop */
2850
fprintf_plus(stderr, "Starting Avahi loop search\n");
2853
ret = avahi_loop_with_timeout(simple_poll,
2854
(int)(retry_interval * 1000), &mc);
2856
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2857
(ret == 0) ? "successfully" : "with error");
2863
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2866
/* Cleanup things */
2867
free(mc.interfaces);
2870
avahi_s_service_browser_free(sb);
2872
if(mc.server != NULL)
2873
avahi_server_free(mc.server);
2875
if(simple_poll != NULL)
2876
avahi_simple_poll_free(simple_poll);
2878
if(gnutls_initialized){
2879
gnutls_certificate_free_credentials(mc.cred);
2880
gnutls_global_deinit();
2881
gnutls_dh_params_deinit(mc.dh_params);
2884
if(gpgme_initialized){
2885
gpgme_release(mc.ctx);
2888
/* Cleans up the circular linked list of Mandos servers the client
2890
if(mc.current_server != NULL){
2891
mc.current_server->prev->next = NULL;
2892
while(mc.current_server != NULL){
2893
server *next = mc.current_server->next;
2895
#pragma GCC diagnostic push
2896
#pragma GCC diagnostic ignored "-Wcast-qual"
2898
free((char *)(mc.current_server->ip));
2900
#pragma GCC diagnostic pop
2902
free(mc.current_server);
2903
mc.current_server = next;
2907
/* Re-raise privileges */
2909
ret_errno = raise_privileges();
2912
perror_plus("Failed to raise privileges");
2915
/* Run network hooks */
2916
run_network_hooks("stop", interfaces_hooks != NULL ?
2917
interfaces_hooks : "", delay);
2919
/* Take down the network interfaces which were brought up */
2921
char *interface = NULL;
2922
while((interface=argz_next(interfaces_to_take_down,
2923
interfaces_to_take_down_size,
2925
ret_errno = take_down_interface(interface);
2928
perror_plus("Failed to take down interface");
2931
if(debug and (interfaces_to_take_down == NULL)){
2932
fprintf_plus(stderr, "No interfaces needed to be taken"
2938
ret_errno = lower_privileges_permanently();
2941
perror_plus("Failed to lower privileges permanently");
2945
free(interfaces_to_take_down);
2946
free(interfaces_hooks);
2948
/* Removes the GPGME temp directory and all files inside */
2949
if(tempdir != NULL){
2950
struct dirent **direntries = NULL;
2951
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
2955
if(tempdir_fd == -1){
2956
perror_plus("open");
2959
#if __GLIBC_PREREQ(2, 15)
2960
int numentries = scandirat(tempdir_fd, ".", &direntries,
2961
notdotentries, alphasort);
2962
#else /* not __GLIBC_PREREQ(2, 15) */
2963
int numentries = scandir(tempdir, &direntries, notdotentries,
2965
#endif /* not __GLIBC_PREREQ(2, 15) */
2966
#else /* not __GLIBC__ */
2967
int numentries = scandir(tempdir, &direntries, notdotentries,
2969
#endif /* not __GLIBC__ */
2970
if(numentries >= 0){
2971
for(int i = 0; i < numentries; i++){
2972
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2974
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2975
" \"%s\", 0): %s\n", tempdir,
2976
direntries[i]->d_name, strerror(errno));
2978
free(direntries[i]);
2981
/* need to clean even if 0 because man page doesn't specify */
2983
if(numentries == -1){
2984
perror_plus("scandir");
2986
ret = rmdir(tempdir);
2987
if(ret == -1 and errno != ENOENT){
2988
perror_plus("rmdir");
2991
TEMP_FAILURE_RETRY(close(tempdir_fd));
2996
sigemptyset(&old_sigterm_action.sa_mask);
2997
old_sigterm_action.sa_handler = SIG_DFL;
2998
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2999
&old_sigterm_action,
3002
perror_plus("sigaction");
3005
ret = raise(signal_received);
3006
} while(ret != 0 and errno == EINTR);
3008
perror_plus("raise");
3011
TEMP_FAILURE_RETRY(pause());