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
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* <http://avahi.org/browser/examples/core-browse-services.c>. This
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* includes the following functions: "resolve_callback",
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* "browse_callback", and parts of "main".
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* Copyright © 2008,2009 Teddy Hogeborn
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* Copyright © 2008,2009 Björn Påhlsson
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* This program is free software: you can redistribute it and/or
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* 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
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* 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@fukt.bsnet.se>.
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/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
#define _LARGEFILE_SOURCE
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#ifndef _FILE_OFFSET_BITS
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#define _FILE_OFFSET_BITS 64
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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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stdout, ferror(), remove() */
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#include <stdint.h> /* uint16_t, uint32_t */
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#include <stddef.h> /* NULL, size_t, ssize_t */
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#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
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#include <stdbool.h> /* bool, false, true */
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#include <string.h> /* memset(), strcmp(), strlen(),
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strerror(), asprintf(), strcpy() */
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#include <sys/ioctl.h> /* ioctl */
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#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(),
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#include <sys/stat.h> /* open() */
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#include <sys/socket.h> /* socket(), struct sockaddr_in6,
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inet_pton(), connect() */
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#include <fcntl.h> /* open() */
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
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#include <assert.h> /* assert() */
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#include <errno.h> /* perror(), errno */
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#include <time.h> /* nanosleep(), time() */
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#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
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SIOCSIFFLAGS, if_indextoname(),
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if_nametoindex(), IF_NAMESIZE */
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#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
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INET_ADDRSTRLEN, INET6_ADDRSTRLEN
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#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
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getuid(), getgid(), setuid(),
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#include <arpa/inet.h> /* inet_pton(), htons */
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#include <iso646.h> /* not, or, and */
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#include <argp.h> /* struct argp_option, error_t, struct
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argp_state, struct argp,
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argp_parse(), ARGP_KEY_ARG,
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ARGP_KEY_END, ARGP_ERR_UNKNOWN */
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#include <signal.h> /* sigemptyset(), sigaddset(),
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sigaction(), SIGTERM, sig_atomic_t,
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#include <sys/klog.h> /* klogctl() */
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#endif /* __linux__ */
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/* All Avahi types, constants and functions
94
#include <avahi-core/core.h>
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#include <avahi-core/lookup.h>
96
#include <avahi-core/log.h>
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#include <avahi-common/simple-watch.h>
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#include <avahi-common/malloc.h>
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#include <avahi-common/error.h>
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#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
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init_gnutls_session(),
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#include <gnutls/openpgp.h>
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/* gnutls_certificate_set_openpgp_key_file(),
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GNUTLS_OPENPGP_FMT_BASE64 */
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#include <gpgme.h> /* All GPGME types, constants and
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GPGME_PROTOCOL_OpenPGP,
118
#define BUFFER_SIZE 256
120
#define PATHDIR "/conf/conf.d/mandos"
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#define SECKEY "seckey.txt"
122
#define PUBKEY "pubkey.txt"
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static const char mandos_protocol_version[] = "1";
126
const char *argp_program_version = "mandos-client " VERSION;
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
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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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/* global context so signal handler can reach it*/
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mandos_context mc = { .simple_poll = NULL, .server = NULL,
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.dh_bits = 1024, .priority = "SECURE256"
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":!CTYPE-X.509:+CTYPE-OPENPGP" };
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* Make additional room in "buffer" for at least BUFFER_SIZE more
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* bytes. "buffer_capacity" is how much is currently allocated,
148
* "buffer_length" is how much is already used.
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size_t incbuffer(char **buffer, size_t buffer_length,
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size_t buffer_capacity){
152
if(buffer_length + BUFFER_SIZE > buffer_capacity){
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*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
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buffer_capacity += BUFFER_SIZE;
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return buffer_capacity;
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static bool init_gpgme(const char *seckey,
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const char *pubkey, const char *tempdir){
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gpgme_engine_info_t engine_info;
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* Helper function to insert pub and seckey to the engine keyring.
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bool import_key(const char *filename){
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gpgme_data_t pgp_data;
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fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
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rc = gpgme_data_new_from_fd(&pgp_data, fd);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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rc = gpgme_op_import(mc.ctx, pgp_data);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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ret = (int)TEMP_FAILURE_RETRY(close(fd));
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gpgme_data_release(pgp_data);
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fprintf(stderr, "Initializing GPGME\n");
212
gpgme_check_version(NULL);
213
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
214
if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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/* Set GPGME home directory for the OpenPGP engine only */
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rc = gpgme_get_engine_info(&engine_info);
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if(rc != GPG_ERR_NO_ERROR){
223
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
227
while(engine_info != NULL){
228
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
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gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
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engine_info->file_name, tempdir);
233
engine_info = engine_info->next;
235
if(engine_info == NULL){
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fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
240
/* Create new GPGME "context" */
241
rc = gpgme_new(&(mc.ctx));
242
if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
248
if(not import_key(pubkey) or not import_key(seckey)){
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* Decrypt OpenPGP data.
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* Returns -1 on error
259
static ssize_t pgp_packet_decrypt(const char *cryptotext,
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gpgme_data_t dh_crypto, dh_plain;
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size_t plaintext_capacity = 0;
266
ssize_t plaintext_length = 0;
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
272
/* Create new GPGME data buffer from memory cryptotext */
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
275
if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
281
/* Create new empty GPGME data buffer for the plaintext */
282
rc = gpgme_data_new(&dh_plain);
283
if(rc != GPG_ERR_NO_ERROR){
284
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
286
gpgme_data_release(dh_crypto);
290
/* Decrypt data from the cryptotext data buffer to the plaintext
292
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
293
if(rc != GPG_ERR_NO_ERROR){
294
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
295
gpgme_strsource(rc), gpgme_strerror(rc));
296
plaintext_length = -1;
298
gpgme_decrypt_result_t result;
299
result = gpgme_op_decrypt_result(mc.ctx);
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
303
fprintf(stderr, "Unsupported algorithm: %s\n",
304
result->unsupported_algorithm);
305
fprintf(stderr, "Wrong key usage: %u\n",
306
result->wrong_key_usage);
307
if(result->file_name != NULL){
308
fprintf(stderr, "File name: %s\n", result->file_name);
310
gpgme_recipient_t recipient;
311
recipient = result->recipients;
312
while(recipient != NULL){
313
fprintf(stderr, "Public key algorithm: %s\n",
314
gpgme_pubkey_algo_name(recipient->pubkey_algo));
315
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
316
fprintf(stderr, "Secret key available: %s\n",
317
recipient->status == GPG_ERR_NO_SECKEY
319
recipient = recipient->next;
327
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
330
/* Seek back to the beginning of the GPGME plaintext data buffer */
331
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
332
perror("gpgme_data_seek");
333
plaintext_length = -1;
339
plaintext_capacity = incbuffer(plaintext,
340
(size_t)plaintext_length,
342
if(plaintext_capacity == 0){
344
plaintext_length = -1;
348
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
350
/* Print the data, if any */
356
perror("gpgme_data_read");
357
plaintext_length = -1;
360
plaintext_length += ret;
364
fprintf(stderr, "Decrypted password is: ");
365
for(ssize_t i = 0; i < plaintext_length; i++){
366
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
368
fprintf(stderr, "\n");
373
/* Delete the GPGME cryptotext data buffer */
374
gpgme_data_release(dh_crypto);
376
/* Delete the GPGME plaintext data buffer */
377
gpgme_data_release(dh_plain);
378
return plaintext_length;
381
static const char * safer_gnutls_strerror(int value){
382
const char *ret = gnutls_strerror(value); /* Spurious warning from
383
-Wunreachable-code */
389
/* GnuTLS log function callback */
390
static void debuggnutls(__attribute__((unused)) int level,
392
fprintf(stderr, "GnuTLS: %s", string);
395
static int init_gnutls_global(const char *pubkeyfilename,
396
const char *seckeyfilename){
400
fprintf(stderr, "Initializing GnuTLS\n");
403
ret = gnutls_global_init();
404
if(ret != GNUTLS_E_SUCCESS){
405
fprintf(stderr, "GnuTLS global_init: %s\n",
406
safer_gnutls_strerror(ret));
411
/* "Use a log level over 10 to enable all debugging options."
414
gnutls_global_set_log_level(11);
415
gnutls_global_set_log_function(debuggnutls);
418
/* OpenPGP credentials */
419
gnutls_certificate_allocate_credentials(&mc.cred);
420
if(ret != GNUTLS_E_SUCCESS){
421
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
425
safer_gnutls_strerror(ret));
426
gnutls_global_deinit();
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
436
ret = gnutls_certificate_set_openpgp_key_file
437
(mc.cred, pubkeyfilename, seckeyfilename,
438
GNUTLS_OPENPGP_FMT_BASE64);
439
if(ret != GNUTLS_E_SUCCESS){
441
"Error[%d] while reading the OpenPGP key pair ('%s',"
442
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
443
fprintf(stderr, "The GnuTLS error is: %s\n",
444
safer_gnutls_strerror(ret));
448
/* GnuTLS server initialization */
449
ret = gnutls_dh_params_init(&mc.dh_params);
450
if(ret != GNUTLS_E_SUCCESS){
451
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
452
" %s\n", safer_gnutls_strerror(ret));
455
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
456
if(ret != GNUTLS_E_SUCCESS){
457
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
458
safer_gnutls_strerror(ret));
462
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
468
gnutls_certificate_free_credentials(mc.cred);
469
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
474
static int init_gnutls_session(gnutls_session_t *session){
476
/* GnuTLS session creation */
477
ret = gnutls_init(session, GNUTLS_SERVER);
478
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
480
safer_gnutls_strerror(ret));
485
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
486
if(ret != GNUTLS_E_SUCCESS){
487
fprintf(stderr, "Syntax error at: %s\n", err);
488
fprintf(stderr, "GnuTLS error: %s\n",
489
safer_gnutls_strerror(ret));
490
gnutls_deinit(*session);
495
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
497
if(ret != GNUTLS_E_SUCCESS){
498
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
499
safer_gnutls_strerror(ret));
500
gnutls_deinit(*session);
504
/* ignore client certificate if any. */
505
gnutls_certificate_server_set_request(*session,
508
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
513
/* Avahi log function callback */
514
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
515
__attribute__((unused)) const char *txt){}
517
sig_atomic_t quit_now = 0;
518
int signal_received = 0;
520
/* Called when a Mandos server is found */
521
static int start_mandos_communication(const char *ip, uint16_t port,
522
AvahiIfIndex if_index,
524
int ret, tcp_sd = -1;
527
struct sockaddr_in in;
528
struct sockaddr_in6 in6;
531
char *decrypted_buffer;
532
size_t buffer_length = 0;
533
size_t buffer_capacity = 0;
534
ssize_t decrypted_buffer_size;
537
gnutls_session_t session;
538
int pf; /* Protocol family */
552
fprintf(stderr, "Bad address family: %d\n", af);
556
ret = init_gnutls_session(&session);
562
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
566
tcp_sd = socket(pf, SOCK_STREAM, 0);
577
memset(&to, 0, sizeof(to));
579
to.in6.sin6_family = (sa_family_t)af;
580
ret = inet_pton(af, ip, &to.in6.sin6_addr);
582
to.in.sin_family = (sa_family_t)af;
583
ret = inet_pton(af, ip, &to.in.sin_addr);
591
fprintf(stderr, "Bad address: %s\n", ip);
596
to.in6.sin6_port = htons(port); /* Spurious warnings from
598
-Wunreachable-code */
600
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
601
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
603
if(if_index == AVAHI_IF_UNSPEC){
604
fprintf(stderr, "An IPv6 link-local address is incomplete"
605
" without a network interface\n");
609
/* Set the network interface number as scope */
610
to.in6.sin6_scope_id = (uint32_t)if_index;
613
to.in.sin_port = htons(port); /* Spurious warnings from
615
-Wunreachable-code */
623
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
624
char interface[IF_NAMESIZE];
625
if(if_indextoname((unsigned int)if_index, interface) == NULL){
626
perror("if_indextoname");
628
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
629
ip, interface, port);
632
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
635
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
636
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
639
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
642
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
648
if(strcmp(addrstr, ip) != 0){
649
fprintf(stderr, "Canonical address form: %s\n", addrstr);
659
ret = connect(tcp_sd, &to.in6, sizeof(to));
661
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
673
const char *out = mandos_protocol_version;
676
size_t out_size = strlen(out);
677
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
678
out_size - written));
684
written += (size_t)ret;
685
if(written < out_size){
688
if(out == mandos_protocol_version){
702
fprintf(stderr, "Establishing TLS session with %s\n", ip);
709
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
716
ret = gnutls_handshake(session);
720
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
722
if(ret != GNUTLS_E_SUCCESS){
724
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
731
/* Read OpenPGP packet that contains the wanted password */
734
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
744
buffer_capacity = incbuffer(&buffer, buffer_length,
746
if(buffer_capacity == 0){
756
sret = gnutls_record_recv(session, buffer+buffer_length,
763
case GNUTLS_E_INTERRUPTED:
766
case GNUTLS_E_REHANDSHAKE:
768
ret = gnutls_handshake(session);
773
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
775
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
782
fprintf(stderr, "Unknown error while reading data from"
783
" encrypted session with Mandos server\n");
785
gnutls_bye(session, GNUTLS_SHUT_RDWR);
789
buffer_length += (size_t) sret;
794
fprintf(stderr, "Closing TLS session\n");
801
gnutls_bye(session, GNUTLS_SHUT_RDWR);
807
if(buffer_length > 0){
808
decrypted_buffer_size = pgp_packet_decrypt(buffer,
811
if(decrypted_buffer_size >= 0){
813
while(written < (size_t) decrypted_buffer_size){
818
ret = (int)fwrite(decrypted_buffer + written, 1,
819
(size_t)decrypted_buffer_size - written,
821
if(ret == 0 and ferror(stdout)){
823
fprintf(stderr, "Error writing encrypted data: %s\n",
829
written += (size_t)ret;
831
free(decrypted_buffer);
839
/* Shutdown procedure */
844
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
849
gnutls_deinit(session);
856
static void resolve_callback(AvahiSServiceResolver *r,
857
AvahiIfIndex interface,
859
AvahiResolverEvent event,
863
const char *host_name,
864
const AvahiAddress *address,
866
AVAHI_GCC_UNUSED AvahiStringList *txt,
867
AVAHI_GCC_UNUSED AvahiLookupResultFlags
869
AVAHI_GCC_UNUSED void* userdata){
872
/* Called whenever a service has been resolved successfully or
881
case AVAHI_RESOLVER_FAILURE:
882
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
883
" of type '%s' in domain '%s': %s\n", name, type, domain,
884
avahi_strerror(avahi_server_errno(mc.server)));
887
case AVAHI_RESOLVER_FOUND:
889
char ip[AVAHI_ADDRESS_STR_MAX];
890
avahi_address_snprint(ip, sizeof(ip), address);
892
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
893
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
894
ip, (intmax_t)interface, port);
896
int ret = start_mandos_communication(ip, port, interface,
897
avahi_proto_to_af(proto));
899
avahi_simple_poll_quit(mc.simple_poll);
903
avahi_s_service_resolver_free(r);
906
static void browse_callback(AvahiSServiceBrowser *b,
907
AvahiIfIndex interface,
908
AvahiProtocol protocol,
909
AvahiBrowserEvent event,
913
AVAHI_GCC_UNUSED AvahiLookupResultFlags
915
AVAHI_GCC_UNUSED void* userdata){
918
/* Called whenever a new services becomes available on the LAN or
919
is removed from the LAN */
927
case AVAHI_BROWSER_FAILURE:
929
fprintf(stderr, "(Avahi browser) %s\n",
930
avahi_strerror(avahi_server_errno(mc.server)));
931
avahi_simple_poll_quit(mc.simple_poll);
934
case AVAHI_BROWSER_NEW:
935
/* We ignore the returned Avahi resolver object. In the callback
936
function we free it. If the Avahi server is terminated before
937
the callback function is called the Avahi server will free the
940
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
941
name, type, domain, protocol, 0,
942
resolve_callback, NULL) == NULL)
943
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
944
name, avahi_strerror(avahi_server_errno(mc.server)));
947
case AVAHI_BROWSER_REMOVE:
950
case AVAHI_BROWSER_ALL_FOR_NOW:
951
case AVAHI_BROWSER_CACHE_EXHAUSTED:
953
fprintf(stderr, "No Mandos server found, still searching...\n");
959
/* stop main loop after sigterm has been called */
960
static void handle_sigterm(int sig){
965
signal_received = sig;
966
int old_errno = errno;
967
if(mc.simple_poll != NULL){
968
avahi_simple_poll_quit(mc.simple_poll);
973
int main(int argc, char *argv[]){
974
AvahiSServiceBrowser *sb = NULL;
979
int exitcode = EXIT_SUCCESS;
980
const char *interface = "eth0";
981
struct ifreq network;
983
bool take_down_interface = false;
986
char *connect_to = NULL;
987
char tempdir[] = "/tmp/mandosXXXXXX";
988
bool tempdir_created = false;
989
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
990
const char *seckey = PATHDIR "/" SECKEY;
991
const char *pubkey = PATHDIR "/" PUBKEY;
993
bool gnutls_initialized = false;
994
bool gpgme_initialized = false;
997
struct sigaction old_sigterm_action;
998
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1001
struct argp_option options[] = {
1002
{ .name = "debug", .key = 128,
1003
.doc = "Debug mode", .group = 3 },
1004
{ .name = "connect", .key = 'c',
1005
.arg = "ADDRESS:PORT",
1006
.doc = "Connect directly to a specific Mandos server",
1008
{ .name = "interface", .key = 'i',
1010
.doc = "Network interface that will be used to search for"
1013
{ .name = "seckey", .key = 's',
1015
.doc = "OpenPGP secret key file base name",
1017
{ .name = "pubkey", .key = 'p',
1019
.doc = "OpenPGP public key file base name",
1021
{ .name = "dh-bits", .key = 129,
1023
.doc = "Bit length of the prime number used in the"
1024
" Diffie-Hellman key exchange",
1026
{ .name = "priority", .key = 130,
1028
.doc = "GnuTLS priority string for the TLS handshake",
1030
{ .name = "delay", .key = 131,
1032
.doc = "Maximum delay to wait for interface startup",
1037
error_t parse_opt(int key, char *arg,
1038
struct argp_state *state){
1040
case 128: /* --debug */
1043
case 'c': /* --connect */
1046
case 'i': /* --interface */
1049
case 's': /* --seckey */
1052
case 'p': /* --pubkey */
1055
case 129: /* --dh-bits */
1057
tmpmax = strtoimax(arg, &tmp, 10);
1058
if(errno != 0 or tmp == arg or *tmp != '\0'
1059
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1060
fprintf(stderr, "Bad number of DH bits\n");
1063
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1065
case 130: /* --priority */
1068
case 131: /* --delay */
1070
delay = strtof(arg, &tmp);
1071
if(errno != 0 or tmp == arg or *tmp != '\0'){
1072
fprintf(stderr, "Bad delay\n");
1081
return ARGP_ERR_UNKNOWN;
1086
struct argp argp = { .options = options, .parser = parse_opt,
1088
.doc = "Mandos client -- Get and decrypt"
1089
" passwords from a Mandos server" };
1090
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1091
if(ret == ARGP_ERR_UNKNOWN){
1092
fprintf(stderr, "Unknown error while parsing arguments\n");
1093
exitcode = EXIT_FAILURE;
1099
avahi_set_log_function(empty_log);
1102
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1103
from the signal handler */
1104
/* Initialize the pseudo-RNG for Avahi */
1105
srand((unsigned int) time(NULL));
1106
mc.simple_poll = avahi_simple_poll_new();
1107
if(mc.simple_poll == NULL){
1108
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1109
exitcode = EXIT_FAILURE;
1113
sigemptyset(&sigterm_action.sa_mask);
1114
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1116
perror("sigaddset");
1117
exitcode = EXIT_FAILURE;
1120
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1122
perror("sigaddset");
1123
exitcode = EXIT_FAILURE;
1126
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1128
perror("sigaddset");
1129
exitcode = EXIT_FAILURE;
1132
/* Need to check if the handler is SIG_IGN before handling:
1133
| [[info:libc:Initial Signal Actions]] |
1134
| [[info:libc:Basic Signal Handling]] |
1136
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1138
perror("sigaction");
1139
return EXIT_FAILURE;
1141
if(old_sigterm_action.sa_handler != SIG_IGN){
1142
ret = sigaction(SIGINT, &sigterm_action, NULL);
1144
perror("sigaction");
1145
exitcode = EXIT_FAILURE;
1149
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1151
perror("sigaction");
1152
return EXIT_FAILURE;
1154
if(old_sigterm_action.sa_handler != SIG_IGN){
1155
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1157
perror("sigaction");
1158
exitcode = EXIT_FAILURE;
1162
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1164
perror("sigaction");
1165
return EXIT_FAILURE;
1167
if(old_sigterm_action.sa_handler != SIG_IGN){
1168
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1170
perror("sigaction");
1171
exitcode = EXIT_FAILURE;
1176
/* If the interface is down, bring it up */
1177
if(interface[0] != '\0'){
1178
if_index = (AvahiIfIndex) if_nametoindex(interface);
1180
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1181
exitcode = EXIT_FAILURE;
1190
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1191
messages to mess up the prompt */
1192
ret = klogctl(8, NULL, 5);
1193
bool restore_loglevel = true;
1195
restore_loglevel = false;
1198
#endif /* __linux__ */
1200
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1203
exitcode = EXIT_FAILURE;
1205
if(restore_loglevel){
1206
ret = klogctl(7, NULL, 0);
1211
#endif /* __linux__ */
1214
strcpy(network.ifr_name, interface);
1215
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1217
perror("ioctl SIOCGIFFLAGS");
1219
if(restore_loglevel){
1220
ret = klogctl(7, NULL, 0);
1225
#endif /* __linux__ */
1226
exitcode = EXIT_FAILURE;
1229
if((network.ifr_flags & IFF_UP) == 0){
1230
network.ifr_flags |= IFF_UP;
1231
take_down_interface = true;
1232
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1234
take_down_interface = false;
1235
perror("ioctl SIOCSIFFLAGS");
1236
exitcode = EXIT_FAILURE;
1238
if(restore_loglevel){
1239
ret = klogctl(7, NULL, 0);
1244
#endif /* __linux__ */
1248
/* sleep checking until interface is running */
1249
for(int i=0; i < delay * 4; i++){
1250
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1252
perror("ioctl SIOCGIFFLAGS");
1253
} else if(network.ifr_flags & IFF_RUNNING){
1256
struct timespec sleeptime = { .tv_nsec = 250000000 };
1257
ret = nanosleep(&sleeptime, NULL);
1258
if(ret == -1 and errno != EINTR){
1259
perror("nanosleep");
1262
if(not take_down_interface){
1263
/* We won't need the socket anymore */
1264
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1270
if(restore_loglevel){
1271
/* Restores kernel loglevel to default */
1272
ret = klogctl(7, NULL, 0);
1277
#endif /* __linux__ */
1302
ret = init_gnutls_global(pubkey, seckey);
1304
fprintf(stderr, "init_gnutls_global failed\n");
1305
exitcode = EXIT_FAILURE;
1308
gnutls_initialized = true;
1315
tempdir_created = true;
1316
if(mkdtemp(tempdir) == NULL){
1317
tempdir_created = false;
1326
if(not init_gpgme(pubkey, seckey, tempdir)){
1327
fprintf(stderr, "init_gpgme failed\n");
1328
exitcode = EXIT_FAILURE;
1331
gpgme_initialized = true;
1338
if(connect_to != NULL){
1339
/* Connect directly, do not use Zeroconf */
1340
/* (Mainly meant for debugging) */
1341
char *address = strrchr(connect_to, ':');
1342
if(address == NULL){
1343
fprintf(stderr, "No colon in address\n");
1344
exitcode = EXIT_FAILURE;
1354
tmpmax = strtoimax(address+1, &tmp, 10);
1355
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1356
or tmpmax != (uint16_t)tmpmax){
1357
fprintf(stderr, "Bad port number\n");
1358
exitcode = EXIT_FAILURE;
1366
port = (uint16_t)tmpmax;
1368
address = connect_to;
1369
/* Colon in address indicates IPv6 */
1371
if(strchr(address, ':') != NULL){
1381
ret = start_mandos_communication(address, port, if_index, af);
1383
exitcode = EXIT_FAILURE;
1385
exitcode = EXIT_SUCCESS;
1395
AvahiServerConfig config;
1396
/* Do not publish any local Zeroconf records */
1397
avahi_server_config_init(&config);
1398
config.publish_hinfo = 0;
1399
config.publish_addresses = 0;
1400
config.publish_workstation = 0;
1401
config.publish_domain = 0;
1403
/* Allocate a new server */
1404
mc.server = avahi_server_new(avahi_simple_poll_get
1405
(mc.simple_poll), &config, NULL,
1408
/* Free the Avahi configuration data */
1409
avahi_server_config_free(&config);
1412
/* Check if creating the Avahi server object succeeded */
1413
if(mc.server == NULL){
1414
fprintf(stderr, "Failed to create Avahi server: %s\n",
1415
avahi_strerror(error));
1416
exitcode = EXIT_FAILURE;
1424
/* Create the Avahi service browser */
1425
sb = avahi_s_service_browser_new(mc.server, if_index,
1426
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1427
NULL, 0, browse_callback, NULL);
1429
fprintf(stderr, "Failed to create service browser: %s\n",
1430
avahi_strerror(avahi_server_errno(mc.server)));
1431
exitcode = EXIT_FAILURE;
1439
/* Run the main loop */
1442
fprintf(stderr, "Starting Avahi loop search\n");
1445
avahi_simple_poll_loop(mc.simple_poll);
1450
fprintf(stderr, "%s exiting\n", argv[0]);
1453
/* Cleanup things */
1455
avahi_s_service_browser_free(sb);
1457
if(mc.server != NULL)
1458
avahi_server_free(mc.server);
1460
if(mc.simple_poll != NULL)
1461
avahi_simple_poll_free(mc.simple_poll);
1463
if(gnutls_initialized){
1464
gnutls_certificate_free_credentials(mc.cred);
1465
gnutls_global_deinit();
1466
gnutls_dh_params_deinit(mc.dh_params);
1469
if(gpgme_initialized){
1470
gpgme_release(mc.ctx);
1473
/* Take down the network interface */
1474
if(take_down_interface){
1475
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1477
perror("ioctl SIOCGIFFLAGS");
1478
} else if(network.ifr_flags & IFF_UP) {
1479
network.ifr_flags &= ~IFF_UP; /* clear flag */
1480
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1482
perror("ioctl SIOCSIFFLAGS");
1485
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1491
/* Removes the temp directory used by GPGME */
1492
if(tempdir_created){
1494
struct dirent *direntry;
1495
d = opendir(tempdir);
1497
if(errno != ENOENT){
1502
direntry = readdir(d);
1503
if(direntry == NULL){
1506
/* Skip "." and ".." */
1507
if(direntry->d_name[0] == '.'
1508
and (direntry->d_name[1] == '\0'
1509
or (direntry->d_name[1] == '.'
1510
and direntry->d_name[2] == '\0'))){
1513
char *fullname = NULL;
1514
ret = asprintf(&fullname, "%s/%s", tempdir,
1520
ret = remove(fullname);
1522
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1529
ret = rmdir(tempdir);
1530
if(ret == -1 and errno != ENOENT){
1536
sigemptyset(&old_sigterm_action.sa_mask);
1537
old_sigterm_action.sa_handler = SIG_DFL;
1538
ret = sigaction(signal_received, &old_sigterm_action, NULL);
1540
perror("sigaction");
1542
raise(signal_received);