1
/* -*- coding: utf-8 -*- */
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* Mandos-client - get and decrypt data from a Mandos server
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* 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
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@fukt.bsnet.se>.
2
This file is part of avahi.
4
avahi is free software; you can redistribute it and/or modify it
5
under the terms of the GNU Lesser General Public License as
6
published by the Free Software Foundation; either version 2.1 of the
7
License, or (at your option) any later version.
9
avahi is distributed in the hope that it will be useful, but WITHOUT
10
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12
Public License for more details.
14
You should have received a copy of the GNU Lesser General Public
15
License along with avahi; if not, write to the Free Software
16
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
20
#define _LARGEFILE_SOURCE
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21
#define _FILE_OFFSET_BITS 64
36
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
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#include <stdio.h> /* fprintf(), stderr, fwrite(),
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stdout, ferror(), sscanf */
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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, 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, INET6_ADDRSTRLEN,
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uid_t, gid_t, open(), opendir(),
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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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struct in6_addr, inet_pton(),
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#include <fcntl.h> /* open() */
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#include <dirent.h> /* opendir(), struct dirent, readdir()
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#include <inttypes.h> /* PRIu16, SCNu16 */
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#include <assert.h> /* assert() */
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#include <errno.h> /* perror(), errno */
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#include <time.h> /* 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 */
67
#include <netinet/in.h>
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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, and, or */
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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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/* All Avahi types, constants and functions
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#include <net/if.h> /* if_nametoindex */
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29
#include <avahi-core/core.h>
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30
#include <avahi-core/lookup.h>
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31
#include <avahi-core/log.h>
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33
#include <avahi-common/malloc.h>
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34
#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,
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#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
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#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
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#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
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#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
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#include <unistd.h> /* close() */
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#include <netinet/in.h>
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#include <stdbool.h> /* true */
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#include <string.h> /* memset */
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#include <arpa/inet.h> /* inet_pton() */
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#include <iso646.h> /* not */
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#include <errno.h> /* perror() */
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#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
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#define CERTFILE CERT_ROOT "openpgp-client.txt"
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#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
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#define BUFFER_SIZE 256
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#define PATHDIR "/conf/conf.d/mandos"
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#define SECKEY "seckey.txt"
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#define PUBKEY "pubkey.txt"
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bool debug = false;
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static const char mandos_protocol_version[] = "1";
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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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char *interface = "eth0";
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/* Used for passing in values through the Avahi callback functions */
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AvahiSimplePoll *simple_poll;
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gnutls_session_t session;
121
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gnutls_certificate_credentials_t cred;
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unsigned int dh_bits;
123
70
gnutls_dh_params_t dh_params;
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const char *priority;
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ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
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gpgme_data_t dh_crypto, dh_plain;
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* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
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* "buffer_capacity" is how much is currently allocated,
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* "buffer_length" is how much is already used.
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size_t adjustbuffer(char **buffer, size_t buffer_length,
134
size_t buffer_capacity){
135
if(buffer_length + BUFFER_SIZE > buffer_capacity){
136
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
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buffer_capacity += BUFFER_SIZE;
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return buffer_capacity;
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
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const char *pubkey, const char *tempdir){
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size_t new_packet_capacity = 0;
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size_t new_packet_length = 0;
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gpgme_engine_info_t engine_info;
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* Helper function to insert pub and seckey to the enigne keyring.
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bool import_key(const char *filename){
160
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, "Initialize gpgme\n");
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fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
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gpgme_check_version(NULL);
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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
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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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gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
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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){
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/* Set GPGME home directory */
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rc = gpgme_get_engine_info (&engine_info);
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if (rc != GPG_ERR_NO_ERROR){
206
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fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
207
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gpgme_strsource(rc), gpgme_strerror(rc));
210
98
while(engine_info != NULL){
211
99
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
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100
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
213
engine_info->file_name, tempdir);
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engine_info->file_name, homedir);
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engine_info = engine_info->next;
218
106
if(engine_info == NULL){
219
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
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/* Create new GPGME "context" */
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rc = gpgme_new(&(mc->ctx));
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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));
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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
242
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
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const char *cryptotext,
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gpgme_data_t dh_crypto, dh_plain;
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size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
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fprintf(stderr, "Trying to decrypt OpenPGP data\n");
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/* Create new GPGME data buffer from memory cryptotext */
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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "Could not set home dir to %s\n", homedir);
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/* Create new GPGME data buffer from packet buffer */
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rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
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if (rc != GPG_ERR_NO_ERROR){
260
114
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
265
119
/* Create new empty GPGME data buffer for the plaintext */
266
120
rc = gpgme_data_new(&dh_plain);
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if(rc != GPG_ERR_NO_ERROR){
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if (rc != GPG_ERR_NO_ERROR){
268
122
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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gpgme_data_release(dh_crypto);
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/* Decrypt data from the cryptotext data buffer to the plaintext
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rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
277
if(rc != GPG_ERR_NO_ERROR){
127
/* Create new GPGME "context" */
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rc = gpgme_new(&ctx);
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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));
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/* Decrypt data from the FILE pointer to the plaintext data buffer */
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rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
137
if (rc != GPG_ERR_NO_ERROR){
278
138
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
279
139
gpgme_strsource(rc), gpgme_strerror(rc));
280
plaintext_length = -1;
282
gpgme_decrypt_result_t result;
283
result = gpgme_op_decrypt_result(mc->ctx);
285
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
287
fprintf(stderr, "Unsupported algorithm: %s\n",
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result->unsupported_algorithm);
289
fprintf(stderr, "Wrong key usage: %u\n",
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result->wrong_key_usage);
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if(result->file_name != NULL){
292
fprintf(stderr, "File name: %s\n", result->file_name);
294
gpgme_recipient_t recipient;
295
recipient = result->recipients;
297
while(recipient != NULL){
298
fprintf(stderr, "Public key algorithm: %s\n",
299
gpgme_pubkey_algo_name(recipient->pubkey_algo));
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fprintf(stderr, "Key ID: %s\n", recipient->keyid);
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fprintf(stderr, "Secret key available: %s\n",
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recipient->status == GPG_ERR_NO_SECKEY
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recipient = recipient->next;
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fprintf(stderr, "decryption of gpg packet succeeded\n");
148
gpgme_decrypt_result_t result;
149
result = gpgme_op_decrypt_result(ctx);
151
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
153
fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage);
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if(result->file_name != NULL){
156
fprintf(stderr, "File name: %s\n", result->file_name);
158
gpgme_recipient_t recipient;
159
recipient = result->recipients;
161
while(recipient != NULL){
162
fprintf(stderr, "Public key algorithm: %s\n",
163
gpgme_pubkey_algo_name(recipient->pubkey_algo));
164
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
165
fprintf(stderr, "Secret key available: %s\n",
166
recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
167
recipient = recipient->next;
313
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
173
/* Delete the GPGME FILE pointer cryptotext data buffer */
174
gpgme_data_release(dh_crypto);
316
176
/* Seek back to the beginning of the GPGME plaintext data buffer */
317
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
318
perror("gpgme_data_seek");
319
plaintext_length = -1;
177
gpgme_data_seek(dh_plain, 0, SEEK_SET);
325
plaintext_capacity = adjustbuffer(plaintext,
326
(size_t)plaintext_length,
328
if(plaintext_capacity == 0){
329
perror("adjustbuffer");
330
plaintext_length = -1;
181
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
182
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
183
if (*new_packet == NULL){
187
new_packet_capacity += BUFFER_SIZE;
334
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
190
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
336
191
/* Print the data, if any */
193
/* If password is empty, then a incorrect error will be printed */
342
197
perror("gpgme_data_read");
343
plaintext_length = -1;
346
plaintext_length += ret;
350
fprintf(stderr, "Decrypted password is: ");
351
for(ssize_t i = 0; i < plaintext_length; i++){
352
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
354
fprintf(stderr, "\n");
359
/* Delete the GPGME cryptotext data buffer */
360
gpgme_data_release(dh_crypto);
200
new_packet_length += ret;
203
/* FIXME: check characters before printing to screen so to not print
204
terminal control characters */
206
/* fprintf(stderr, "decrypted password is: "); */
207
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
208
/* fprintf(stderr, "\n"); */
362
211
/* Delete the GPGME plaintext data buffer */
363
212
gpgme_data_release(dh_plain);
364
return plaintext_length;
213
return new_packet_length;
367
static const char * safer_gnutls_strerror(int value) {
368
const char *ret = gnutls_strerror(value); /* Spurious warning from
369
-Wunreachable-code */
216
static const char * safer_gnutls_strerror (int value) {
217
const char *ret = gnutls_strerror (value);
371
219
ret = "(unknown)";
375
/* GnuTLS log function callback */
376
static void debuggnutls(__attribute__((unused)) int level,
378
fprintf(stderr, "GnuTLS: %s", string);
223
void debuggnutls(int level, const char* string){
224
fprintf(stderr, "%s", string);
381
static int init_gnutls_global(mandos_context *mc,
382
const char *pubkeyfilename,
383
const char *seckeyfilename){
227
int initgnutls(encrypted_session *es){
387
fprintf(stderr, "Initializing GnuTLS\n");
232
fprintf(stderr, "Initializing gnutls\n");
390
ret = gnutls_global_init();
391
if(ret != GNUTLS_E_SUCCESS) {
392
fprintf(stderr, "GnuTLS global_init: %s\n",
393
safer_gnutls_strerror(ret));
236
if ((ret = gnutls_global_init ())
237
!= GNUTLS_E_SUCCESS) {
238
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
398
/* "Use a log level over 10 to enable all debugging options."
401
243
gnutls_global_set_log_level(11);
402
244
gnutls_global_set_log_function(debuggnutls);
405
/* OpenPGP credentials */
406
gnutls_certificate_allocate_credentials(&mc->cred);
407
if(ret != GNUTLS_E_SUCCESS){
408
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
412
safer_gnutls_strerror(ret));
413
gnutls_global_deinit();
248
/* openpgp credentials */
249
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
250
!= GNUTLS_E_SUCCESS) {
251
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
418
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
419
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
256
fprintf(stderr, "Attempting to use openpgp certificate %s"
257
" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
423
260
ret = gnutls_certificate_set_openpgp_key_file
424
(mc->cred, pubkeyfilename, seckeyfilename,
425
GNUTLS_OPENPGP_FMT_BASE64);
426
if(ret != GNUTLS_E_SUCCESS) {
428
"Error[%d] while reading the OpenPGP key pair ('%s',"
429
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
430
fprintf(stderr, "The GnuTLS error is: %s\n",
431
safer_gnutls_strerror(ret));
435
/* GnuTLS server initialization */
436
ret = gnutls_dh_params_init(&mc->dh_params);
437
if(ret != GNUTLS_E_SUCCESS) {
438
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
439
" %s\n", safer_gnutls_strerror(ret));
442
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
443
if(ret != GNUTLS_E_SUCCESS) {
444
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
445
safer_gnutls_strerror(ret));
449
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
455
gnutls_certificate_free_credentials(mc->cred);
456
gnutls_global_deinit();
457
gnutls_dh_params_deinit(mc->dh_params);
461
static int init_gnutls_session(mandos_context *mc,
462
gnutls_session_t *session){
464
/* GnuTLS session creation */
465
ret = gnutls_init(session, GNUTLS_SERVER);
466
if(ret != GNUTLS_E_SUCCESS){
467
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
468
safer_gnutls_strerror(ret));
473
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
474
if(ret != GNUTLS_E_SUCCESS) {
475
fprintf(stderr, "Syntax error at: %s\n", err);
476
fprintf(stderr, "GnuTLS error: %s\n",
477
safer_gnutls_strerror(ret));
478
gnutls_deinit(*session);
483
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
485
if(ret != GNUTLS_E_SUCCESS) {
486
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
487
safer_gnutls_strerror(ret));
488
gnutls_deinit(*session);
261
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
262
if (ret != GNUTLS_E_SUCCESS) {
264
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
265
ret, CERTFILE, KEYFILE);
266
fprintf(stdout, "The Error is: %s\n",
267
safer_gnutls_strerror(ret));
271
//Gnutls server initialization
272
if ((ret = gnutls_dh_params_init (&es->dh_params))
273
!= GNUTLS_E_SUCCESS) {
274
fprintf (stderr, "Error in dh parameter initialization: %s\n",
275
safer_gnutls_strerror(ret));
279
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
280
!= GNUTLS_E_SUCCESS) {
281
fprintf (stderr, "Error in prime generation: %s\n",
282
safer_gnutls_strerror(ret));
286
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
288
// Gnutls session creation
289
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
290
!= GNUTLS_E_SUCCESS){
291
fprintf(stderr, "Error in gnutls session initialization: %s\n",
292
safer_gnutls_strerror(ret));
295
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
296
!= GNUTLS_E_SUCCESS) {
297
fprintf(stderr, "Syntax error at: %s\n", err);
298
fprintf(stderr, "Gnutls error: %s\n",
299
safer_gnutls_strerror(ret));
303
if ((ret = gnutls_credentials_set
304
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
305
!= GNUTLS_E_SUCCESS) {
306
fprintf(stderr, "Error setting a credentials set: %s\n",
307
safer_gnutls_strerror(ret));
492
311
/* ignore client certificate if any. */
493
gnutls_certificate_server_set_request(*session,
312
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
496
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
314
gnutls_dh_set_prime_bits (es->session, DH_BITS);
501
/* Avahi log function callback */
502
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
503
__attribute__((unused)) const char *txt){}
319
void empty_log(AvahiLogLevel level, const char *txt){}
505
/* Called when a Mandos server is found */
506
static int start_mandos_communication(const char *ip, uint16_t port,
507
AvahiIfIndex if_index,
321
int start_mandos_communcation(char *ip, uint16_t port){
511
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
323
struct sockaddr_in6 to;
324
struct in6_addr ip_addr;
325
encrypted_session es;
512
326
char *buffer = NULL;
513
327
char *decrypted_buffer;
514
328
size_t buffer_length = 0;
515
329
size_t buffer_capacity = 0;
516
330
ssize_t decrypted_buffer_size;
519
char interface[IF_NAMESIZE];
520
gnutls_session_t session;
522
ret = init_gnutls_session(mc, &session);
528
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
334
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
532
337
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
534
339
perror("socket");
539
if(if_indextoname((unsigned int)if_index, interface) == NULL){
540
perror("if_indextoname");
543
344
fprintf(stderr, "Binding to interface %s\n", interface);
347
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
349
perror("setsockopt bindtodevice");
546
memset(&to, 0, sizeof(to));
547
to.in6.sin6_family = AF_INET6;
548
/* It would be nice to have a way to detect if we were passed an
549
IPv4 address here. Now we assume an IPv6 address. */
550
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
353
memset(&to,0,sizeof(to));
354
to.sin6_family = AF_INET6;
355
ret = inet_pton(AF_INET6, ip, &ip_addr);
552
357
perror("inet_pton");
556
361
fprintf(stderr, "Bad address: %s\n", ip);
559
to.in6.sin6_port = htons(port); /* Spurious warnings from
561
-Wunreachable-code */
563
to.in6.sin6_scope_id = (uint32_t)if_index;
364
to.sin6_port = htons(port);
365
to.sin6_scope_id = if_nametoindex(interface);
566
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
568
char addrstr[INET6_ADDRSTRLEN] = "";
569
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
570
sizeof(addrstr)) == NULL){
573
if(strcmp(addrstr, ip) != 0){
574
fprintf(stderr, "Canonical address form: %s\n", addrstr);
368
fprintf(stderr, "Connection to: %s\n", ip);
579
ret = connect(tcp_sd, &to.in, sizeof(to));
371
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
581
373
perror("connect");
585
const char *out = mandos_protocol_version;
377
ret = initgnutls (&es);
384
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
387
fprintf(stderr, "Establishing tls session with %s\n", ip);
391
ret = gnutls_handshake (es.session);
393
if (ret != GNUTLS_E_SUCCESS){
394
fprintf(stderr, "\n*** Handshake failed ***\n");
400
//Retrieve gpg packet that contains the wanted password
403
fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
588
size_t out_size = strlen(out);
589
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
590
out_size - written));
596
written += (size_t)ret;
597
if(written < out_size){
600
if(out == mandos_protocol_version){
407
if (buffer_length + BUFFER_SIZE > buffer_capacity){
408
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
610
fprintf(stderr, "Establishing TLS session with %s\n", ip);
613
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
616
ret = gnutls_handshake(session);
617
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
619
if(ret != GNUTLS_E_SUCCESS){
621
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
628
/* Read OpenPGP packet that contains the wanted password */
631
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
636
buffer_capacity = adjustbuffer(&buffer, buffer_length,
638
if(buffer_capacity == 0){
639
perror("adjustbuffer");
413
buffer_capacity += BUFFER_SIZE;
644
sret = gnutls_record_recv(session, buffer+buffer_length,
416
ret = gnutls_record_recv
417
(es.session, buffer+buffer_length, BUFFER_SIZE);
651
423
case GNUTLS_E_INTERRUPTED:
652
424
case GNUTLS_E_AGAIN:
654
426
case GNUTLS_E_REHANDSHAKE:
656
ret = gnutls_handshake(session);
657
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
659
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
427
ret = gnutls_handshake (es.session);
429
fprintf(stderr, "\n*** Handshake failed ***\n");
666
fprintf(stderr, "Unknown error while reading data from"
667
" encrypted session with Mandos server\n");
436
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
669
gnutls_bye(session, GNUTLS_SHUT_RDWR);
438
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
673
buffer_length += (size_t) sret;
442
buffer_length += ret;
678
fprintf(stderr, "Closing TLS session\n");
681
gnutls_bye(session, GNUTLS_SHUT_RDWR);
683
if(buffer_length > 0){
684
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
687
if(decrypted_buffer_size >= 0){
689
while(written < (size_t) decrypted_buffer_size){
690
ret = (int)fwrite(decrypted_buffer + written, 1,
691
(size_t)decrypted_buffer_size - written,
693
if(ret == 0 and ferror(stdout)){
695
fprintf(stderr, "Error writing encrypted data: %s\n",
701
written += (size_t)ret;
446
if (buffer_length > 0){
447
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) >= 0){
448
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
703
449
free(decrypted_buffer);
711
/* Shutdown procedure */
458
fprintf(stderr, "Closing tls session\n");
715
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
719
gnutls_deinit(session);
462
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
465
gnutls_deinit (es.session);
466
gnutls_certificate_free_credentials (es.cred);
467
gnutls_global_deinit ();
723
static void resolve_callback(AvahiSServiceResolver *r,
724
AvahiIfIndex interface,
725
AVAHI_GCC_UNUSED AvahiProtocol protocol,
726
AvahiResolverEvent event,
730
const char *host_name,
731
const AvahiAddress *address,
733
AVAHI_GCC_UNUSED AvahiStringList *txt,
734
AVAHI_GCC_UNUSED AvahiLookupResultFlags
737
mandos_context *mc = userdata;
740
/* Called whenever a service has been resolved successfully or
745
case AVAHI_RESOLVER_FAILURE:
746
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
747
" of type '%s' in domain '%s': %s\n", name, type, domain,
748
avahi_strerror(avahi_server_errno(mc->server)));
751
case AVAHI_RESOLVER_FOUND:
753
char ip[AVAHI_ADDRESS_STR_MAX];
754
avahi_address_snprint(ip, sizeof(ip), address);
756
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
757
PRIu16 ") on port %d\n", name, host_name, ip,
760
int ret = start_mandos_communication(ip, port, interface, mc);
762
avahi_simple_poll_quit(mc->simple_poll);
766
avahi_s_service_resolver_free(r);
769
static void browse_callback( AvahiSServiceBrowser *b,
770
AvahiIfIndex interface,
771
AvahiProtocol protocol,
772
AvahiBrowserEvent event,
776
AVAHI_GCC_UNUSED AvahiLookupResultFlags
779
mandos_context *mc = userdata;
782
/* Called whenever a new services becomes available on the LAN or
783
is removed from the LAN */
787
case AVAHI_BROWSER_FAILURE:
789
fprintf(stderr, "(Avahi browser) %s\n",
790
avahi_strerror(avahi_server_errno(mc->server)));
791
avahi_simple_poll_quit(mc->simple_poll);
794
case AVAHI_BROWSER_NEW:
795
/* We ignore the returned Avahi resolver object. In the callback
796
function we free it. If the Avahi server is terminated before
797
the callback function is called the Avahi server will free the
800
if(!(avahi_s_service_resolver_new(mc->server, interface,
801
protocol, name, type, domain,
802
AVAHI_PROTO_INET6, 0,
803
resolve_callback, mc)))
804
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
805
name, avahi_strerror(avahi_server_errno(mc->server)));
808
case AVAHI_BROWSER_REMOVE:
811
case AVAHI_BROWSER_ALL_FOR_NOW:
812
case AVAHI_BROWSER_CACHE_EXHAUSTED:
814
fprintf(stderr, "No Mandos server found, still searching...\n");
820
int main(int argc, char *argv[]){
471
static AvahiSimplePoll *simple_poll = NULL;
472
static AvahiServer *server = NULL;
474
static void resolve_callback(
475
AvahiSServiceResolver *r,
476
AVAHI_GCC_UNUSED AvahiIfIndex interface,
477
AVAHI_GCC_UNUSED AvahiProtocol protocol,
478
AvahiResolverEvent event,
482
const char *host_name,
483
const AvahiAddress *address,
485
AvahiStringList *txt,
486
AvahiLookupResultFlags flags,
487
AVAHI_GCC_UNUSED void* userdata) {
491
/* Called whenever a service has been resolved successfully or timed out */
494
case AVAHI_RESOLVER_FAILURE:
495
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s\n", name, type, domain, avahi_strerror(avahi_server_errno(server)));
498
case AVAHI_RESOLVER_FOUND: {
499
char ip[AVAHI_ADDRESS_STR_MAX];
500
avahi_address_snprint(ip, sizeof(ip), address);
502
fprintf(stderr, "Mandos server found at %s on port %d\n", ip, port);
504
int ret = start_mandos_communcation(ip, port);
512
avahi_s_service_resolver_free(r);
515
static void browse_callback(
516
AvahiSServiceBrowser *b,
517
AvahiIfIndex interface,
518
AvahiProtocol protocol,
519
AvahiBrowserEvent event,
523
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
526
AvahiServer *s = userdata;
529
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
533
case AVAHI_BROWSER_FAILURE:
535
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
536
avahi_simple_poll_quit(simple_poll);
539
case AVAHI_BROWSER_NEW:
540
/* We ignore the returned resolver object. In the callback
541
function we free it. If the server is terminated before
542
the callback function is called the server will free
543
the resolver for us. */
545
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
546
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
550
case AVAHI_BROWSER_REMOVE:
553
case AVAHI_BROWSER_ALL_FOR_NOW:
554
case AVAHI_BROWSER_CACHE_EXHAUSTED:
559
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
560
AvahiServerConfig config;
821
561
AvahiSServiceBrowser *sb = NULL;
824
int exitcode = EXIT_SUCCESS;
825
const char *interface = "eth0";
826
struct ifreq network;
830
char *connect_to = NULL;
831
char tempdir[] = "/tmp/mandosXXXXXX";
832
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
833
const char *seckey = PATHDIR "/" SECKEY;
834
const char *pubkey = PATHDIR "/" PUBKEY;
836
mandos_context mc = { .simple_poll = NULL, .server = NULL,
837
.dh_bits = 1024, .priority = "SECURE256"
838
":!CTYPE-X.509:+CTYPE-OPENPGP" };
839
bool gnutls_initalized = false;
840
bool gpgme_initalized = false;
843
struct argp_option options[] = {
844
{ .name = "debug", .key = 128,
845
.doc = "Debug mode", .group = 3 },
846
{ .name = "connect", .key = 'c',
847
.arg = "ADDRESS:PORT",
848
.doc = "Connect directly to a specific Mandos server",
850
{ .name = "interface", .key = 'i',
852
.doc = "Interface that will be used to search for Mandos"
855
{ .name = "seckey", .key = 's',
857
.doc = "OpenPGP secret key file base name",
859
{ .name = "pubkey", .key = 'p',
861
.doc = "OpenPGP public key file base name",
863
{ .name = "dh-bits", .key = 129,
865
.doc = "Bit length of the prime number used in the"
866
" Diffie-Hellman key exchange",
868
{ .name = "priority", .key = 130,
870
.doc = "GnuTLS priority string for the TLS handshake",
875
error_t parse_opt(int key, char *arg,
876
struct argp_state *state) {
878
case 128: /* --debug */
881
case 'c': /* --connect */
884
case 'i': /* --interface */
887
case 's': /* --seckey */
890
case 'p': /* --pubkey */
893
case 129: /* --dh-bits */
894
ret = sscanf(arg, "%u", &mc.dh_bits);
896
fprintf(stderr, "Bad number of DH bits\n");
900
case 130: /* --priority */
908
return ARGP_ERR_UNKNOWN;
913
struct argp argp = { .options = options, .parser = parse_opt,
915
.doc = "Mandos client -- Get and decrypt"
916
" passwords from a Mandos server" };
917
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
918
if(ret == ARGP_ERR_UNKNOWN){
919
fprintf(stderr, "Unknown error while parsing arguments\n");
920
exitcode = EXIT_FAILURE;
925
/* If the interface is down, bring it up */
927
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
930
exitcode = EXIT_FAILURE;
933
strcpy(network.ifr_name, interface);
934
ret = ioctl(sd, SIOCGIFFLAGS, &network);
936
perror("ioctl SIOCGIFFLAGS");
937
exitcode = EXIT_FAILURE;
940
if((network.ifr_flags & IFF_UP) == 0){
941
network.ifr_flags |= IFF_UP;
942
ret = ioctl(sd, SIOCSIFFLAGS, &network);
944
perror("ioctl SIOCSIFFLAGS");
945
exitcode = EXIT_FAILURE;
949
ret = (int)TEMP_FAILURE_RETRY(close(sd));
968
ret = init_gnutls_global(&mc, pubkey, seckey);
970
fprintf(stderr, "init_gnutls_global failed\n");
971
exitcode = EXIT_FAILURE;
974
gnutls_initalized = true;
977
if(mkdtemp(tempdir) == NULL){
983
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
984
fprintf(stderr, "gpgme_initalized failed\n");
985
exitcode = EXIT_FAILURE;
988
gpgme_initalized = true;
991
if_index = (AvahiIfIndex) if_nametoindex(interface);
993
fprintf(stderr, "No such interface: \"%s\"\n", interface);
997
if(connect_to != NULL){
998
/* Connect directly, do not use Zeroconf */
999
/* (Mainly meant for debugging) */
1000
char *address = strrchr(connect_to, ':');
1001
if(address == NULL){
1002
fprintf(stderr, "No colon in address\n");
1003
exitcode = EXIT_FAILURE;
1007
ret = sscanf(address+1, "%" SCNu16, &port);
1009
fprintf(stderr, "Bad port number\n");
1010
exitcode = EXIT_FAILURE;
1014
address = connect_to;
1015
ret = start_mandos_communication(address, port, if_index, &mc);
1017
exitcode = EXIT_FAILURE;
1019
exitcode = EXIT_SUCCESS;
564
int returncode = EXIT_SUCCESS;
567
static struct option long_options[] = {
568
{"debug", no_argument, (int *)&debug, 1},
569
{"interface", required_argument, 0, 'i'},
572
int option_index = 0;
573
ret = getopt_long (argc, argv, "i:", long_options, &option_index);
1025
591
avahi_set_log_function(empty_log);
1028
/* Initialize the pseudo-RNG for Avahi */
1029
srand((unsigned int) time(NULL));
1031
/* Allocate main Avahi loop object */
1032
mc.simple_poll = avahi_simple_poll_new();
1033
if(mc.simple_poll == NULL) {
1034
fprintf(stderr, "Avahi: Failed to create simple poll"
1036
exitcode = EXIT_FAILURE;
1041
AvahiServerConfig config;
1042
/* Do not publish any local Zeroconf records */
1043
avahi_server_config_init(&config);
1044
config.publish_hinfo = 0;
1045
config.publish_addresses = 0;
1046
config.publish_workstation = 0;
1047
config.publish_domain = 0;
1049
/* Allocate a new server */
1050
mc.server = avahi_server_new(avahi_simple_poll_get
1051
(mc.simple_poll), &config, NULL,
1054
/* Free the Avahi configuration data */
1055
avahi_server_config_free(&config);
1058
/* Check if creating the Avahi server object succeeded */
1059
if(mc.server == NULL) {
1060
fprintf(stderr, "Failed to create Avahi server: %s\n",
1061
avahi_strerror(error));
1062
exitcode = EXIT_FAILURE;
1066
/* Create the Avahi service browser */
1067
sb = avahi_s_service_browser_new(mc.server, if_index,
1069
"_mandos._tcp", NULL, 0,
1070
browse_callback, &mc);
1072
fprintf(stderr, "Failed to create service browser: %s\n",
1073
avahi_strerror(avahi_server_errno(mc.server)));
1074
exitcode = EXIT_FAILURE;
594
/* Initialize the psuedo-RNG */
597
/* Allocate main loop object */
598
if (!(simple_poll = avahi_simple_poll_new())) {
599
fprintf(stderr, "Failed to create simple poll object.\n");
604
/* Do not publish any local records */
605
avahi_server_config_init(&config);
606
config.publish_hinfo = 0;
607
config.publish_addresses = 0;
608
config.publish_workstation = 0;
609
config.publish_domain = 0;
611
/* Allocate a new server */
612
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
614
/* Free the configuration data */
615
avahi_server_config_free(&config);
617
/* Check if creating the server object succeeded */
619
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
620
returncode = EXIT_FAILURE;
624
/* Create the service browser */
625
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
626
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
627
returncode = EXIT_FAILURE;
1078
631
/* Run the main loop */
1081
fprintf(stderr, "Starting Avahi loop search\n");
634
fprintf(stderr, "Starting avahi loop search\n");
1084
avahi_simple_poll_loop(mc.simple_poll);
637
avahi_simple_poll_loop(simple_poll);
1089
642
fprintf(stderr, "%s exiting\n", argv[0]);
1092
645
/* Cleanup things */
1094
647
avahi_s_service_browser_free(sb);
1096
if(mc.server != NULL)
1097
avahi_server_free(mc.server);
1099
if(mc.simple_poll != NULL)
1100
avahi_simple_poll_free(mc.simple_poll);
1102
if(gnutls_initalized){
1103
gnutls_certificate_free_credentials(mc.cred);
1104
gnutls_global_deinit();
1105
gnutls_dh_params_deinit(mc.dh_params);
1108
if(gpgme_initalized){
1109
gpgme_release(mc.ctx);
1112
/* Removes the temp directory used by GPGME */
1113
if(tempdir[0] != '\0'){
1115
struct dirent *direntry;
1116
d = opendir(tempdir);
1118
if(errno != ENOENT){
1123
direntry = readdir(d);
1124
if(direntry == NULL){
1127
if(direntry->d_type == DT_REG){
1128
char *fullname = NULL;
1129
ret = asprintf(&fullname, "%s/%s", tempdir,
1135
ret = unlink(fullname);
1137
fprintf(stderr, "unlink(\"%s\"): %s",
1138
fullname, strerror(errno));
1145
ret = rmdir(tempdir);
1146
if(ret == -1 and errno != ENOENT){
650
avahi_server_free(server);
653
avahi_simple_poll_free(simple_poll);