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/* -*- coding: utf-8 -*- */
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* Mandos-client - get and decrypt data from a Mandos server
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* This file demonstrates how to use Avahi's core API, this is
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* the embeddable mDNS stack for embedded applications.
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* This program is partly derived from an example program for an Avahi
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* 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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* End user applications should *not* use this API and should use
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* the D-Bus or C APIs, please see
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* client-browse-services.c and glib-integration.c
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* I repeat, you probably do *not* want to use this example.
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/* Needed by GPGME, specifically gpgme_data_seek() */
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This file is part of avahi.
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avahi is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as
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published by the Free Software Foundation; either version 2.1 of the
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License, or (at your option) any later version.
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avahi is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
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Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with avahi; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
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#define _LARGEFILE_SOURCE
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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(), 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, intmax_t, SCNdMAX */
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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>
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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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#include <sys/klog.h> /* klogctl() */
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/* All Avahi types, constants and functions
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#include <net/if.h> /* if_nametoindex */
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#include <avahi-core/core.h>
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43
#include <avahi-core/lookup.h>
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#include <avahi-core/log.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,
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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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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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/* 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;
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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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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,
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size_t buffer_capacity){
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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(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 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, "Initialize gpgme\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){
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fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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while(engine_info != NULL){
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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);
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engine_info->file_name, homedir);
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engine_info = engine_info->next;
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if(engine_info == NULL){
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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
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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){
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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));
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/* Create new empty GPGME data buffer for the plaintext */
268
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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){
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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);
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if(rc != GPG_ERR_NO_ERROR){
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/* 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);
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if (rc != GPG_ERR_NO_ERROR){
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142
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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plaintext_length = -1;
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gpgme_decrypt_result_t result;
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result = gpgme_op_decrypt_result(mc->ctx);
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fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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fprintf(stderr, "Unsupported algorithm: %s\n",
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result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %u\n",
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result->wrong_key_usage);
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if(result->file_name != NULL){
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fprintf(stderr, "File name: %s\n", result->file_name);
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gpgme_recipient_t recipient;
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recipient = result->recipients;
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while(recipient != NULL){
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fprintf(stderr, "Public key algorithm: %s\n",
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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 OpenPGP data succeeded\n");
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/* gpgme_decrypt_result_t result; */
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/* result = gpgme_op_decrypt_result(ctx); */
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/* 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){ */
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/* fprintf(stderr, "File name: %s\n", result->file_name); */
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/* gpgme_recipient_t recipient; */
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/* recipient = result->recipients; */
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/* while(recipient != NULL){ */
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/* fprintf(stderr, "Public key algorithm: %s\n", */
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/* 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 ? "No" : "Yes"); */
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/* recipient = recipient->next; */
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/* Delete the GPGME FILE pointer cryptotext data buffer */
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gpgme_data_release(dh_crypto);
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/* Seek back to the beginning of the GPGME plaintext data buffer */
319
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
320
perror("gpgme_data_seek");
321
plaintext_length = -1;
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gpgme_data_seek(dh_plain, 0, SEEK_SET);
327
plaintext_capacity = adjustbuffer(plaintext,
328
(size_t)plaintext_length,
330
if(plaintext_capacity == 0){
331
perror("adjustbuffer");
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plaintext_length = -1;
175
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
176
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
177
if (*new_packet == NULL){
181
new_packet_capacity += BUFFER_SIZE;
336
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
184
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
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185
/* Print the data, if any */
187
/* If password is empty, then a incorrect error will be printed */
344
191
perror("gpgme_data_read");
345
plaintext_length = -1;
348
plaintext_length += ret;
352
fprintf(stderr, "Decrypted password is: ");
353
for(ssize_t i = 0; i < plaintext_length; i++){
354
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
356
fprintf(stderr, "\n");
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/* Delete the GPGME cryptotext data buffer */
362
gpgme_data_release(dh_crypto);
364
/* Delete the GPGME plaintext data buffer */
194
new_packet_length += ret;
197
/* Delete the GPGME plaintext data buffer */
365
198
gpgme_data_release(dh_plain);
366
return plaintext_length;
199
return new_packet_length;
369
static const char * safer_gnutls_strerror(int value) {
370
const char *ret = gnutls_strerror(value); /* Spurious warning from
371
-Wunreachable-code */
202
static const char * safer_gnutls_strerror (int value) {
203
const char *ret = gnutls_strerror (value);
373
205
ret = "(unknown)";
377
/* GnuTLS log function callback */
378
static void debuggnutls(__attribute__((unused)) int level,
380
fprintf(stderr, "GnuTLS: %s", string);
209
void debuggnutls(int level, const char* string){
210
fprintf(stderr, "%s", string);
383
static int init_gnutls_global(mandos_context *mc,
384
const char *pubkeyfilename,
385
const char *seckeyfilename){
213
int initgnutls(encrypted_session *es){
389
fprintf(stderr, "Initializing GnuTLS\n");
392
ret = gnutls_global_init();
393
if(ret != GNUTLS_E_SUCCESS) {
394
fprintf(stderr, "GnuTLS global_init: %s\n",
395
safer_gnutls_strerror(ret));
400
/* "Use a log level over 10 to enable all debugging options."
403
gnutls_global_set_log_level(11);
404
gnutls_global_set_log_function(debuggnutls);
407
/* OpenPGP credentials */
408
gnutls_certificate_allocate_credentials(&mc->cred);
409
if(ret != GNUTLS_E_SUCCESS){
410
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
414
safer_gnutls_strerror(ret));
415
gnutls_global_deinit();
420
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
421
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
217
if ((ret = gnutls_global_init ())
218
!= GNUTLS_E_SUCCESS) {
219
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
223
/* Uncomment to enable full debuggin on the gnutls library */
224
/* gnutls_global_set_log_level(11); */
225
/* gnutls_global_set_log_function(debuggnutls); */
228
/* openpgp credentials */
229
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
230
!= GNUTLS_E_SUCCESS) {
231
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
425
235
ret = gnutls_certificate_set_openpgp_key_file
426
(mc->cred, pubkeyfilename, seckeyfilename,
427
GNUTLS_OPENPGP_FMT_BASE64);
428
if(ret != GNUTLS_E_SUCCESS) {
430
"Error[%d] while reading the OpenPGP key pair ('%s',"
431
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
432
fprintf(stderr, "The GnuTLS error is: %s\n",
433
safer_gnutls_strerror(ret));
437
/* GnuTLS server initialization */
438
ret = gnutls_dh_params_init(&mc->dh_params);
439
if(ret != GNUTLS_E_SUCCESS) {
440
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
441
" %s\n", safer_gnutls_strerror(ret));
444
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
445
if(ret != GNUTLS_E_SUCCESS) {
446
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
447
safer_gnutls_strerror(ret));
451
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
457
gnutls_certificate_free_credentials(mc->cred);
458
gnutls_global_deinit();
459
gnutls_dh_params_deinit(mc->dh_params);
463
static int init_gnutls_session(mandos_context *mc,
464
gnutls_session_t *session){
466
/* GnuTLS session creation */
467
ret = gnutls_init(session, GNUTLS_SERVER);
468
if(ret != GNUTLS_E_SUCCESS){
469
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
470
safer_gnutls_strerror(ret));
475
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
476
if(ret != GNUTLS_E_SUCCESS) {
477
fprintf(stderr, "Syntax error at: %s\n", err);
478
fprintf(stderr, "GnuTLS error: %s\n",
479
safer_gnutls_strerror(ret));
480
gnutls_deinit(*session);
485
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
487
if(ret != GNUTLS_E_SUCCESS) {
488
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
489
safer_gnutls_strerror(ret));
490
gnutls_deinit(*session);
236
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
237
if (ret != GNUTLS_E_SUCCESS) {
239
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
240
ret, CERTFILE, KEYFILE);
241
fprintf(stdout, "The Error is: %s\n",
242
safer_gnutls_strerror(ret));
246
//Gnutls server initialization
247
if ((ret = gnutls_dh_params_init (&es->dh_params))
248
!= GNUTLS_E_SUCCESS) {
249
fprintf (stderr, "Error in dh parameter initialization: %s\n",
250
safer_gnutls_strerror(ret));
254
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
255
!= GNUTLS_E_SUCCESS) {
256
fprintf (stderr, "Error in prime generation: %s\n",
257
safer_gnutls_strerror(ret));
261
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
263
// Gnutls session creation
264
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
265
!= GNUTLS_E_SUCCESS){
266
fprintf(stderr, "Error in gnutls session initialization: %s\n",
267
safer_gnutls_strerror(ret));
270
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
271
!= GNUTLS_E_SUCCESS) {
272
fprintf(stderr, "Syntax error at: %s\n", err);
273
fprintf(stderr, "Gnutls error: %s\n",
274
safer_gnutls_strerror(ret));
278
if ((ret = gnutls_credentials_set
279
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
280
!= GNUTLS_E_SUCCESS) {
281
fprintf(stderr, "Error setting a credentials set: %s\n",
282
safer_gnutls_strerror(ret));
494
286
/* ignore client certificate if any. */
495
gnutls_certificate_server_set_request(*session,
287
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
498
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
289
gnutls_dh_set_prime_bits (es->session, DH_BITS);
503
/* Avahi log function callback */
504
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
505
__attribute__((unused)) const char *txt){}
294
void empty_log(AvahiLogLevel level, const char *txt){}
507
/* Called when a Mandos server is found */
508
static int start_mandos_communication(const char *ip, uint16_t port,
509
AvahiIfIndex if_index,
296
int start_mandos_communcation(char *ip, uint16_t port){
513
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
298
struct sockaddr_in6 to;
299
struct in6_addr ip_addr;
300
encrypted_session es;
514
301
char *buffer = NULL;
515
302
char *decrypted_buffer;
516
303
size_t buffer_length = 0;
517
304
size_t buffer_capacity = 0;
518
305
ssize_t decrypted_buffer_size;
521
char interface[IF_NAMESIZE];
522
gnutls_session_t session;
524
ret = init_gnutls_session(mc, &session);
530
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
534
309
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
541
if(if_indextoname((unsigned int)if_index, interface) == NULL){
542
perror("if_indextoname");
545
fprintf(stderr, "Binding to interface %s\n", interface);
315
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, "eth0", 5);
317
perror("setsockopt bindtodevice");
548
memset(&to, 0, sizeof(to));
549
to.in6.sin6_family = AF_INET6;
550
/* It would be nice to have a way to detect if we were passed an
551
IPv4 address here. Now we assume an IPv6 address. */
552
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
321
memset(&to,0,sizeof(to));
322
to.sin6_family = AF_INET6;
323
ret = inet_pton(AF_INET6, ip, &ip_addr);
554
325
perror("inet_pton");
558
329
fprintf(stderr, "Bad address: %s\n", ip);
561
to.in6.sin6_port = htons(port); /* Spurious warnings from
563
-Wunreachable-code */
565
to.in6.sin6_scope_id = (uint32_t)if_index;
568
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
570
char addrstr[INET6_ADDRSTRLEN] = "";
571
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
572
sizeof(addrstr)) == NULL){
575
if(strcmp(addrstr, ip) != 0){
576
fprintf(stderr, "Canonical address form: %s\n", addrstr);
581
ret = connect(tcp_sd, &to.in, sizeof(to));
332
to.sin6_port = htons(port);
333
to.sin6_scope_id = if_nametoindex("eth0");
335
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
583
337
perror("connect");
587
const char *out = mandos_protocol_version;
341
ret = initgnutls (&es);
348
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
350
ret = gnutls_handshake (es.session);
352
if (ret != GNUTLS_E_SUCCESS){
353
fprintf(stderr, "\n*** Handshake failed ***\n");
590
size_t out_size = strlen(out);
591
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
592
out_size - written));
598
written += (size_t)ret;
599
if(written < out_size){
602
if(out == mandos_protocol_version){
361
if (buffer_length + BUFFER_SIZE > buffer_capacity){
362
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
612
fprintf(stderr, "Establishing TLS session with %s\n", ip);
615
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
618
ret = gnutls_handshake(session);
619
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
621
if(ret != GNUTLS_E_SUCCESS){
623
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
630
/* Read OpenPGP packet that contains the wanted password */
633
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
638
buffer_capacity = adjustbuffer(&buffer, buffer_length,
640
if(buffer_capacity == 0){
641
perror("adjustbuffer");
367
buffer_capacity += BUFFER_SIZE;
646
sret = gnutls_record_recv(session, buffer+buffer_length,
370
ret = gnutls_record_recv
371
(es.session, buffer+buffer_length, BUFFER_SIZE);
653
377
case GNUTLS_E_INTERRUPTED:
654
378
case GNUTLS_E_AGAIN:
656
380
case GNUTLS_E_REHANDSHAKE:
658
ret = gnutls_handshake(session);
659
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
661
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
381
ret = gnutls_handshake (es.session);
383
fprintf(stderr, "\n*** Handshake failed ***\n");
668
fprintf(stderr, "Unknown error while reading data from"
669
" encrypted session with Mandos server\n");
390
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
671
gnutls_bye(session, GNUTLS_SHUT_RDWR);
392
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
675
buffer_length += (size_t) sret;
396
buffer_length += ret;
680
fprintf(stderr, "Closing TLS session\n");
683
gnutls_bye(session, GNUTLS_SHUT_RDWR);
685
if(buffer_length > 0){
686
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
689
if(decrypted_buffer_size >= 0){
691
while(written < (size_t) decrypted_buffer_size){
692
ret = (int)fwrite(decrypted_buffer + written, 1,
693
(size_t)decrypted_buffer_size - written,
695
if(ret == 0 and ferror(stdout)){
697
fprintf(stderr, "Error writing encrypted data: %s\n",
703
written += (size_t)ret;
400
if (buffer_length > 0){
401
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) == 0){
404
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
705
405
free(decrypted_buffer);
713
/* Shutdown procedure */
717
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
721
gnutls_deinit(session);
412
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
415
gnutls_deinit (es.session);
416
gnutls_certificate_free_credentials (es.cred);
417
gnutls_global_deinit ();
725
static void resolve_callback(AvahiSServiceResolver *r,
726
AvahiIfIndex interface,
727
AVAHI_GCC_UNUSED AvahiProtocol protocol,
728
AvahiResolverEvent event,
732
const char *host_name,
733
const AvahiAddress *address,
735
AVAHI_GCC_UNUSED AvahiStringList *txt,
736
AVAHI_GCC_UNUSED AvahiLookupResultFlags
739
mandos_context *mc = userdata;
742
/* Called whenever a service has been resolved successfully or
747
case AVAHI_RESOLVER_FAILURE:
748
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
749
" of type '%s' in domain '%s': %s\n", name, type, domain,
750
avahi_strerror(avahi_server_errno(mc->server)));
753
case AVAHI_RESOLVER_FOUND:
755
char ip[AVAHI_ADDRESS_STR_MAX];
756
avahi_address_snprint(ip, sizeof(ip), address);
758
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
759
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
760
ip, (intmax_t)interface, port);
762
int ret = start_mandos_communication(ip, port, interface, mc);
764
avahi_simple_poll_quit(mc->simple_poll);
768
avahi_s_service_resolver_free(r);
771
static void browse_callback( AvahiSServiceBrowser *b,
772
AvahiIfIndex interface,
773
AvahiProtocol protocol,
774
AvahiBrowserEvent event,
778
AVAHI_GCC_UNUSED AvahiLookupResultFlags
781
mandos_context *mc = userdata;
784
/* Called whenever a new services becomes available on the LAN or
785
is removed from the LAN */
789
case AVAHI_BROWSER_FAILURE:
791
fprintf(stderr, "(Avahi browser) %s\n",
792
avahi_strerror(avahi_server_errno(mc->server)));
793
avahi_simple_poll_quit(mc->simple_poll);
796
case AVAHI_BROWSER_NEW:
797
/* We ignore the returned Avahi resolver object. In the callback
798
function we free it. If the Avahi server is terminated before
799
the callback function is called the Avahi server will free the
802
if(!(avahi_s_service_resolver_new(mc->server, interface,
803
protocol, name, type, domain,
804
AVAHI_PROTO_INET6, 0,
805
resolve_callback, mc)))
806
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
807
name, avahi_strerror(avahi_server_errno(mc->server)));
810
case AVAHI_BROWSER_REMOVE:
813
case AVAHI_BROWSER_ALL_FOR_NOW:
814
case AVAHI_BROWSER_CACHE_EXHAUSTED:
816
fprintf(stderr, "No Mandos server found, still searching...\n");
822
int main(int argc, char *argv[]){
421
static AvahiSimplePoll *simple_poll = NULL;
422
static AvahiServer *server = NULL;
424
static void resolve_callback(
425
AvahiSServiceResolver *r,
426
AVAHI_GCC_UNUSED AvahiIfIndex interface,
427
AVAHI_GCC_UNUSED AvahiProtocol protocol,
428
AvahiResolverEvent event,
432
const char *host_name,
433
const AvahiAddress *address,
435
AvahiStringList *txt,
436
AvahiLookupResultFlags flags,
437
AVAHI_GCC_UNUSED void* userdata) {
441
/* Called whenever a service has been resolved successfully or timed out */
444
case AVAHI_RESOLVER_FAILURE:
445
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)));
448
case AVAHI_RESOLVER_FOUND: {
449
char ip[AVAHI_ADDRESS_STR_MAX];
450
avahi_address_snprint(ip, sizeof(ip), address);
451
int ret = start_mandos_communcation(ip, port);
459
avahi_s_service_resolver_free(r);
462
static void browse_callback(
463
AvahiSServiceBrowser *b,
464
AvahiIfIndex interface,
465
AvahiProtocol protocol,
466
AvahiBrowserEvent event,
470
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
473
AvahiServer *s = userdata;
476
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
480
case AVAHI_BROWSER_FAILURE:
482
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
483
avahi_simple_poll_quit(simple_poll);
486
case AVAHI_BROWSER_NEW:
487
/* We ignore the returned resolver object. In the callback
488
function we free it. If the server is terminated before
489
the callback function is called the server will free
490
the resolver for us. */
492
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
493
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
497
case AVAHI_BROWSER_REMOVE:
500
case AVAHI_BROWSER_ALL_FOR_NOW:
501
case AVAHI_BROWSER_CACHE_EXHAUSTED:
506
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
507
AvahiServerConfig config;
823
508
AvahiSServiceBrowser *sb = NULL;
828
int exitcode = EXIT_SUCCESS;
829
const char *interface = "eth0";
830
struct ifreq network;
834
char *connect_to = NULL;
835
char tempdir[] = "/tmp/mandosXXXXXX";
836
bool tempdir_created = false;
837
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
838
const char *seckey = PATHDIR "/" SECKEY;
839
const char *pubkey = PATHDIR "/" PUBKEY;
841
mandos_context mc = { .simple_poll = NULL, .server = NULL,
842
.dh_bits = 1024, .priority = "SECURE256"
843
":!CTYPE-X.509:+CTYPE-OPENPGP" };
844
bool gnutls_initialized = false;
845
bool gpgme_initialized = false;
849
struct argp_option options[] = {
850
{ .name = "debug", .key = 128,
851
.doc = "Debug mode", .group = 3 },
852
{ .name = "connect", .key = 'c',
853
.arg = "ADDRESS:PORT",
854
.doc = "Connect directly to a specific Mandos server",
856
{ .name = "interface", .key = 'i',
858
.doc = "Interface that will be used to search for Mandos"
861
{ .name = "seckey", .key = 's',
863
.doc = "OpenPGP secret key file base name",
865
{ .name = "pubkey", .key = 'p',
867
.doc = "OpenPGP public key file base name",
869
{ .name = "dh-bits", .key = 129,
871
.doc = "Bit length of the prime number used in the"
872
" Diffie-Hellman key exchange",
874
{ .name = "priority", .key = 130,
876
.doc = "GnuTLS priority string for the TLS handshake",
878
{ .name = "delay", .key = 131,
880
.doc = "Maximum delay to wait for interface startup",
885
error_t parse_opt(int key, char *arg,
886
struct argp_state *state) {
888
case 128: /* --debug */
891
case 'c': /* --connect */
894
case 'i': /* --interface */
897
case 's': /* --seckey */
900
case 'p': /* --pubkey */
903
case 129: /* --dh-bits */
904
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
905
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
906
or arg[numchars] != '\0'){
907
fprintf(stderr, "Bad number of DH bits\n");
910
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
912
case 130: /* --priority */
915
case 131: /* --delay */
916
ret = sscanf(arg, "%lf%n", &delay, &numchars);
917
if(ret < 1 or arg[numchars] != '\0'){
918
fprintf(stderr, "Bad delay\n");
927
return ARGP_ERR_UNKNOWN;
932
struct argp argp = { .options = options, .parser = parse_opt,
934
.doc = "Mandos client -- Get and decrypt"
935
" passwords from a Mandos server" };
936
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
937
if(ret == ARGP_ERR_UNKNOWN){
938
fprintf(stderr, "Unknown error while parsing arguments\n");
939
exitcode = EXIT_FAILURE;
944
/* If the interface is down, bring it up */
946
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
947
messages to mess up the prompt */
948
ret = klogctl(8, NULL, 5);
953
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
956
exitcode = EXIT_FAILURE;
957
ret = klogctl(7, NULL, 0);
963
strcpy(network.ifr_name, interface);
964
ret = ioctl(sd, SIOCGIFFLAGS, &network);
966
perror("ioctl SIOCGIFFLAGS");
967
ret = klogctl(7, NULL, 0);
971
exitcode = EXIT_FAILURE;
974
if((network.ifr_flags & IFF_UP) == 0){
975
network.ifr_flags |= IFF_UP;
976
ret = ioctl(sd, SIOCSIFFLAGS, &network);
978
perror("ioctl SIOCSIFFLAGS");
979
exitcode = EXIT_FAILURE;
980
ret = klogctl(7, NULL, 0);
987
/* sleep checking until interface is running */
988
for(int i=0; i < delay * 4; i++){
989
ret = ioctl(sd, SIOCGIFFLAGS, &network);
991
perror("ioctl SIOCGIFFLAGS");
992
} else if(network.ifr_flags & IFF_RUNNING){
995
struct timespec sleeptime = { .tv_nsec = 250000000 };
996
nanosleep(&sleeptime, NULL);
998
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1002
/* Restores kernel loglevel to default */
1003
ret = klogctl(7, NULL, 0);
1022
ret = init_gnutls_global(&mc, pubkey, seckey);
1024
fprintf(stderr, "init_gnutls_global failed\n");
1025
exitcode = EXIT_FAILURE;
1028
gnutls_initialized = true;
1031
if(mkdtemp(tempdir) == NULL){
1035
tempdir_created = true;
1037
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1038
fprintf(stderr, "init_gpgme failed\n");
1039
exitcode = EXIT_FAILURE;
1042
gpgme_initialized = true;
1045
if_index = (AvahiIfIndex) if_nametoindex(interface);
1047
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1048
exitcode = EXIT_FAILURE;
1052
if(connect_to != NULL){
1053
/* Connect directly, do not use Zeroconf */
1054
/* (Mainly meant for debugging) */
1055
char *address = strrchr(connect_to, ':');
1056
if(address == NULL){
1057
fprintf(stderr, "No colon in address\n");
1058
exitcode = EXIT_FAILURE;
1062
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1063
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1064
or address[numchars+1] != '\0'){
1065
fprintf(stderr, "Bad port number\n");
1066
exitcode = EXIT_FAILURE;
1069
port = (uint16_t)tmpmax;
1071
address = connect_to;
1072
ret = start_mandos_communication(address, port, if_index, &mc);
1074
exitcode = EXIT_FAILURE;
1076
exitcode = EXIT_SUCCESS;
1082
avahi_set_log_function(empty_log);
1085
/* Initialize the pseudo-RNG for Avahi */
1086
srand((unsigned int) time(NULL));
1088
/* Allocate main Avahi loop object */
1089
mc.simple_poll = avahi_simple_poll_new();
1090
if(mc.simple_poll == NULL) {
1091
fprintf(stderr, "Avahi: Failed to create simple poll"
1093
exitcode = EXIT_FAILURE;
1098
AvahiServerConfig config;
1099
/* Do not publish any local Zeroconf records */
1100
avahi_server_config_init(&config);
1101
config.publish_hinfo = 0;
1102
config.publish_addresses = 0;
1103
config.publish_workstation = 0;
1104
config.publish_domain = 0;
1106
/* Allocate a new server */
1107
mc.server = avahi_server_new(avahi_simple_poll_get
1108
(mc.simple_poll), &config, NULL,
1111
/* Free the Avahi configuration data */
1112
avahi_server_config_free(&config);
1115
/* Check if creating the Avahi server object succeeded */
1116
if(mc.server == NULL) {
1117
fprintf(stderr, "Failed to create Avahi server: %s\n",
1118
avahi_strerror(error));
1119
exitcode = EXIT_FAILURE;
1123
/* Create the Avahi service browser */
1124
sb = avahi_s_service_browser_new(mc.server, if_index,
1126
"_mandos._tcp", NULL, 0,
1127
browse_callback, &mc);
1129
fprintf(stderr, "Failed to create service browser: %s\n",
1130
avahi_strerror(avahi_server_errno(mc.server)));
1131
exitcode = EXIT_FAILURE;
512
avahi_set_log_function(empty_log);
514
/* Initialize the psuedo-RNG */
517
/* Allocate main loop object */
518
if (!(simple_poll = avahi_simple_poll_new())) {
519
fprintf(stderr, "Failed to create simple poll object.\n");
523
/* Do not publish any local records */
524
avahi_server_config_init(&config);
525
config.publish_hinfo = 0;
526
config.publish_addresses = 0;
527
config.publish_workstation = 0;
528
config.publish_domain = 0;
530
/* /\* Set a unicast DNS server for wide area DNS-SD *\/ */
531
/* avahi_address_parse("193.11.177.11", AVAHI_PROTO_UNSPEC, &config.wide_area_servers[0]); */
532
/* config.n_wide_area_servers = 1; */
533
/* config.enable_wide_area = 1; */
535
/* Allocate a new server */
536
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
538
/* Free the configuration data */
539
avahi_server_config_free(&config);
541
/* Check wether creating the server object succeeded */
543
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
547
/* Create the service browser */
548
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
549
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
1135
553
/* Run the main loop */
1138
fprintf(stderr, "Starting Avahi loop search\n");
1141
avahi_simple_poll_loop(mc.simple_poll);
1146
fprintf(stderr, "%s exiting\n", argv[0]);
554
avahi_simple_poll_loop(simple_poll);
1149
560
/* Cleanup things */
1151
562
avahi_s_service_browser_free(sb);
1153
if(mc.server != NULL)
1154
avahi_server_free(mc.server);
1156
if(mc.simple_poll != NULL)
1157
avahi_simple_poll_free(mc.simple_poll);
1159
if(gnutls_initialized){
1160
gnutls_certificate_free_credentials(mc.cred);
1161
gnutls_global_deinit();
1162
gnutls_dh_params_deinit(mc.dh_params);
1165
if(gpgme_initialized){
1166
gpgme_release(mc.ctx);
1169
/* Removes the temp directory used by GPGME */
1170
if(tempdir_created){
1172
struct dirent *direntry;
1173
d = opendir(tempdir);
1175
if(errno != ENOENT){
1180
direntry = readdir(d);
1181
if(direntry == NULL){
1184
/* Skip "." and ".." */
1185
if(direntry->d_name[0] == '.'
1186
and (direntry->d_name[1] == '\0'
1187
or (direntry->d_name[1] == '.'
1188
and direntry->d_name[2] == '\0'))){
1191
char *fullname = NULL;
1192
ret = asprintf(&fullname, "%s/%s", tempdir,
1198
ret = remove(fullname);
1200
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1207
ret = rmdir(tempdir);
1208
if(ret == -1 and errno != ENOENT){
565
avahi_server_free(server);
568
avahi_simple_poll_free(simple_poll);