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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
15
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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/* -*- 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
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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 © 2007-2008 Teddy Hogeborn & Björn Påhlsson
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* This program is free software: you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@fukt.bsnet.se>.
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/* Needed by GPGME, specifically gpgme_data_seek() */
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#define _LARGEFILE_SOURCE
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#define _FILE_OFFSET_BITS 64
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#include <avahi-common/error.h>
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//mandos client part
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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 <sys/types.h> /* socket(), inet_pton() */
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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 <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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82
} encrypted_session;
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ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
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ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
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char **new_packet, const char *homedir){
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gpgme_data_t dh_crypto, dh_plain;
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size_t new_packet_capacity = 0;
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size_t new_packet_length = 0;
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ssize_t new_packet_capacity = 0;
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ssize_t new_packet_length = 0;
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gpgme_engine_info_t engine_info;
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fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
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fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
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gpgme_check_version(NULL);
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gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
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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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/* Set GPGME home directory */
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rc = gpgme_get_engine_info (&engine_info);
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168
if (result == NULL){
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fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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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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fprintf(stderr, "Unsupported algorithm: %s\n",
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result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %d\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_data_release(dh_crypto);
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/* Seek back to the beginning of the GPGME plaintext data buffer */
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gpgme_data_seek(dh_plain, 0, SEEK_SET);
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if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
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perror("pgpme_data_seek");
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if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
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*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
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*new_packet = realloc(*new_packet,
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(unsigned int)new_packet_capacity
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if (*new_packet == NULL){
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perror("realloc");
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void debuggnutls(int level, const char* string){
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void debuggnutls(__attribute__((unused)) int level,
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fprintf(stderr, "%s", string);
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int initgnutls(encrypted_session *es){
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fprintf(stderr, "Initializing gnutls\n");
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fprintf(stderr, "Initializing GnuTLS\n");
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if ((ret = gnutls_global_init ())
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!= GNUTLS_E_SUCCESS) {
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fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
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gnutls_global_set_log_function(debuggnutls);
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/* openpgp credentials */
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if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
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!= GNUTLS_E_SUCCESS) {
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fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
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fprintf (stderr, "memory error: %s\n",
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safer_gnutls_strerror(ret));
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fprintf(stderr, "Attempting to use openpgp certificate %s"
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" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
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fprintf(stderr, "Attempting to use OpenPGP certificate %s"
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" and keyfile %s as GnuTLS credentials\n", certfile,
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ret = gnutls_certificate_set_openpgp_key_file
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(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
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(es->cred, certfile, certkey, GNUTLS_OPENPGP_FMT_BASE64);
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if (ret != GNUTLS_E_SUCCESS) {
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(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
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ret, CERTFILE, KEYFILE);
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(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
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ret, certfile, certkey);
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fprintf(stdout, "The Error is: %s\n",
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safer_gnutls_strerror(ret));
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//Gnutls server initialization
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//GnuTLS server initialization
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if ((ret = gnutls_dh_params_init (&es->dh_params))
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!= GNUTLS_E_SUCCESS) {
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fprintf (stderr, "Error in dh parameter initialization: %s\n",
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safer_gnutls_strerror(ret));
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if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
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!= GNUTLS_E_SUCCESS) {
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fprintf (stderr, "Error in prime generation: %s\n",
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safer_gnutls_strerror(ret));
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gnutls_certificate_set_dh_params (es->cred, es->dh_params);
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// Gnutls session creation
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// GnuTLS session creation
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if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
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!= GNUTLS_E_SUCCESS){
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fprintf(stderr, "Error in gnutls session initialization: %s\n",
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fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
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safer_gnutls_strerror(ret));
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if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
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!= GNUTLS_E_SUCCESS) {
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fprintf(stderr, "Syntax error at: %s\n", err);
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fprintf(stderr, "Gnutls error: %s\n",
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fprintf(stderr, "GnuTLS error: %s\n",
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safer_gnutls_strerror(ret));
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if ((ret = gnutls_credentials_set
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(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
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!= GNUTLS_E_SUCCESS) {
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safer_gnutls_strerror(ret));
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338
/* ignore client certificate if any. */
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gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
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gnutls_certificate_server_set_request (es->session,
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gnutls_dh_set_prime_bits (es->session, DH_BITS);
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void empty_log(AvahiLogLevel level, const char *txt){}
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void empty_log(__attribute__((unused)) AvahiLogLevel level,
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__attribute__((unused)) const char *txt){}
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int start_mandos_communcation(char *ip, uint16_t port){
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int start_mandos_communication(const char *ip, uint16_t port,
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AvahiIfIndex if_index){
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353
struct sockaddr_in6 to;
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struct in6_addr ip_addr;
325
354
encrypted_session es;
326
355
char *buffer = NULL;
327
356
char *decrypted_buffer;
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size_t buffer_length = 0;
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358
size_t buffer_capacity = 0;
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ssize_t decrypted_buffer_size;
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char interface[IF_NAMESIZE];
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fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
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fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
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tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
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perror("socket");
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if(if_indextoname((unsigned int)if_index, interface) == NULL){
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perror("if_indextoname");
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fprintf(stderr, "Binding to interface %s\n", interface);
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ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
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perror("setsockopt bindtodevice");
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memset(&to,0,sizeof(to));
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memset(&to,0,sizeof(to)); /* Spurious warning */
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to.sin6_family = AF_INET6;
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ret = inet_pton(AF_INET6, ip, &ip_addr);
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ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
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perror("inet_pton");
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fprintf(stderr, "Bad address: %s\n", ip);
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to.sin6_port = htons(port);
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to.sin6_scope_id = if_nametoindex(interface);
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to.sin6_port = htons(port); /* Spurious warning */
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to.sin6_scope_id = (uint32_t)if_index;
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fprintf(stderr, "Connection to: %s\n", ip);
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fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
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/* char addrstr[INET6_ADDRSTRLEN]; */
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/* if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr, */
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/* sizeof(addrstr)) == NULL){ */
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/* perror("inet_ntop"); */
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/* fprintf(stderr, "Really connecting to: %s, port %d\n", */
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/* addrstr, ntohs(to.sin6_port)); */
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413
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
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gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
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gnutls_transport_set_ptr (es.session,
426
(gnutls_transport_ptr_t) tcp_sd);
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fprintf(stderr, "Establishing tls session with %s\n", ip);
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fprintf(stderr, "Establishing TLS session with %s\n", ip);
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432
ret = gnutls_handshake (es.session);
393
434
if (ret != GNUTLS_E_SUCCESS){
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fprintf(stderr, "\n*** Handshake failed ***\n");
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fprintf(stderr, "\n*** Handshake failed ***\n");
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//Retrieve gpg packet that contains the wanted password
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//Retrieve OpenPGP packet that contains the wanted password
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fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
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fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
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fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
480
fprintf(stderr, "Unknown error while reading data from"
481
" encrypted session with mandos server\n");
438
483
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
442
buffer_length += ret;
487
buffer_length += (size_t) ret;
446
491
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);
492
decrypted_buffer_size = pgp_packet_decrypt(buffer,
496
if (decrypted_buffer_size >= 0){
497
while(written < (size_t) decrypted_buffer_size){
498
ret = (int)fwrite (decrypted_buffer + written, 1,
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(size_t)decrypted_buffer_size - written,
501
if(ret == 0 and ferror(stdout)){
503
fprintf(stderr, "Error writing encrypted data: %s\n",
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written += (size_t)ret;
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511
free(decrypted_buffer);
482
544
const char *host_name,
483
545
const AvahiAddress *address,
485
AvahiStringList *txt,
486
AvahiLookupResultFlags flags,
547
AVAHI_GCC_UNUSED AvahiStringList *txt,
548
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
487
549
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);
551
assert(r); /* Spurious warning */
553
/* Called whenever a service has been resolved successfully or
558
case AVAHI_RESOLVER_FAILURE:
559
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of"
560
" type '%s' in domain '%s': %s\n", name, type, domain,
561
avahi_strerror(avahi_server_errno(server)));
564
case AVAHI_RESOLVER_FOUND:
566
char ip[AVAHI_ADDRESS_STR_MAX];
567
avahi_address_snprint(ip, sizeof(ip), address);
569
fprintf(stderr, "Mandos server \"%s\" found on %s (%s) on"
570
" port %d\n", name, host_name, ip, port);
572
int ret = start_mandos_communication(ip, port, interface);
512
avahi_s_service_resolver_free(r);
578
avahi_s_service_resolver_free(r);
515
581
static void browse_callback(
524
590
void* userdata) {
526
592
AvahiServer *s = userdata;
529
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
593
assert(b); /* Spurious warning */
595
/* Called whenever a new services becomes available on the LAN or
596
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:
600
case AVAHI_BROWSER_FAILURE:
602
fprintf(stderr, "(Browser) %s\n",
603
avahi_strerror(avahi_server_errno(server)));
604
avahi_simple_poll_quit(simple_poll);
607
case AVAHI_BROWSER_NEW:
608
/* We ignore the returned resolver object. In the callback
609
function we free it. If the server is terminated before
610
the callback function is called the server will free
611
the resolver for us. */
613
if (!(avahi_s_service_resolver_new(s, interface, protocol, name,
615
AVAHI_PROTO_INET6, 0,
616
resolve_callback, s)))
617
fprintf(stderr, "Failed to resolve service '%s': %s\n", name,
618
avahi_strerror(avahi_server_errno(s)));
621
case AVAHI_BROWSER_REMOVE:
624
case AVAHI_BROWSER_ALL_FOR_NOW:
625
case AVAHI_BROWSER_CACHE_EXHAUSTED:
630
/* combinds file name and path and returns the malloced new string. som sane checks could/should be added */
631
const char *combinepath(const char *first, const char *second){
633
tmp = malloc(strlen(first) + strlen(second) + 2);
639
if (first[0] != '\0' and first[strlen(first) - 1] != '/'){
559
647
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
560
648
AvahiServerConfig config;
561
649
AvahiSServiceBrowser *sb = NULL;
564
652
int returncode = EXIT_SUCCESS;
653
const char *interface = NULL;
654
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
655
char *connect_to = NULL;
567
658
static struct option long_options[] = {
568
659
{"debug", no_argument, (int *)&debug, 1},
660
{"connect", required_argument, 0, 'C'},
569
661
{"interface", required_argument, 0, 'i'},
662
{"certdir", required_argument, 0, 'd'},
663
{"certkey", required_argument, 0, 'c'},
664
{"certfile", required_argument, 0, 'k'},
572
667
int option_index = 0;
573
ret = getopt_long (argc, argv, "i:", long_options, &option_index);
668
ret = getopt_long (argc, argv, "i:", long_options,
583
679
interface = optarg;
586
694
exit(EXIT_FAILURE);
698
certfile = combinepath(certdir, certfile);
699
if (certfile == NULL){
703
if(interface != NULL){
704
if_index = (AvahiIfIndex) if_nametoindex(interface);
706
fprintf(stderr, "No such interface: \"%s\"\n", interface);
711
if(connect_to != NULL){
712
/* Connect directly, do not use Zeroconf */
713
/* (Mainly meant for debugging) */
714
char *address = strrchr(connect_to, ':');
716
fprintf(stderr, "No colon in address\n");
720
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
722
perror("Bad port number");
726
address = connect_to;
727
ret = start_mandos_communication(address, port, if_index);
735
certkey = combinepath(certdir, certkey);
736
if (certkey == NULL){
591
741
avahi_set_log_function(empty_log);
594
744
/* Initialize the psuedo-RNG */
745
srand((unsigned int) time(NULL));
597
747
/* Allocate main loop object */
598
748
if (!(simple_poll = avahi_simple_poll_new())) {
609
759
config.publish_domain = 0;
611
761
/* Allocate a new server */
612
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
762
server = avahi_server_new(avahi_simple_poll_get(simple_poll),
763
&config, NULL, NULL, &error);
614
765
/* Free the configuration data */
615
766
avahi_server_config_free(&config);
617
768
/* Check if creating the server object succeeded */
619
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
770
fprintf(stderr, "Failed to create server: %s\n",
771
avahi_strerror(error));
620
772
returncode = EXIT_FAILURE;
624
776
/* 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)));
777
sb = avahi_s_service_browser_new(server, if_index,
779
"_mandos._tcp", NULL, 0,
780
browse_callback, server);
782
fprintf(stderr, "Failed to create service browser: %s\n",
783
avahi_strerror(avahi_server_errno(server)));
627
784
returncode = EXIT_FAILURE;