/mandos/trunk : revision 204

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/* -*- coding: utf-8 -*- */

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/*

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* Mandos-client - get and decrypt data from a Mandos server

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* Mandos client - get and decrypt data from a Mandos server

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*

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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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* "browse_callback", and parts of "main".

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*

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* Everything else is

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*

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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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#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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remove() */

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stdout, ferror() */

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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 <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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DIR */

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uid_t, gid_t, open(), opendir(), DIR */

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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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connect() */

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#include <fcntl.h> /* open() */

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#include <dirent.h> /* opendir(), struct dirent, readdir()

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*/

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#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */

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#include <dirent.h> /* opendir(), struct dirent, readdir() */

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#include <inttypes.h> /* PRIu16 */

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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 <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 */

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getuid(), getgid(), setuid(),

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setgid() */

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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 <iso646.h> /* not, and */

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#include <argp.h> /* struct argp_option, error_t, struct

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argp_state, struct argp,

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argp_parse(), ARGP_KEY_ARG,

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ARGP_KEY_END, ARGP_ERR_UNKNOWN */

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#include <sys/klog.h> /* klogctl() */

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/* Avahi */

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/* All Avahi types, constants and functions

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gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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#define BUFFER_SIZE 256

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/*

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#define PATHDIR "/conf/conf.d/mandos"

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*/

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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_version = "mandos-client 1.0";

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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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*/

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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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if (buffer_length + BUFFER_SIZE > buffer_capacity){

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*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

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if(buffer == NULL){

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if (buffer == NULL){

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return 0;

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}

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buffer_capacity += BUFFER_SIZE;

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/*

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* Helper function to insert pub and seckey to the engine keyring.

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* Helper function to insert pub and seckey to the enigne keyring.

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*/

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bool import_key(const char *filename){

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int fd;

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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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fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

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if(fd == -1){

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perror("open");

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return false;

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}

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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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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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return false;

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}

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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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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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return false;

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}

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ret = (int)TEMP_FAILURE_RETRY(close(fd));

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ret = TEMP_FAILURE_RETRY(close(fd));

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if(ret == -1){

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perror("close");

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}

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return true;

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}

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if(debug){

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if (debug){

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fprintf(stderr, "Initialize gpgme\n");

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

198

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

199

if(rc != GPG_ERR_NO_ERROR){

197

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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return false;

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}

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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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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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return false;

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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){

225

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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return false;

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}

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if(not import_key(pubkey) or not import_key(seckey)){

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if (not import_key(pubkey) or not import_key(seckey)){

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return false;

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}

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* Decrypt OpenPGP data.

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* Returns -1 on error

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*/

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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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size_t crypto_size,

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char **plaintext){

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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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size_t crypto_size,

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char **plaintext){

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gpgme_data_t dh_crypto, dh_plain;

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gpgme_error_t rc;

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ssize_t ret;

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size_t plaintext_capacity = 0;

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ssize_t plaintext_length = 0;

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if(debug){

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if (debug){

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fprintf(stderr, "Trying to decrypt OpenPGP data\n");

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}

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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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0);

261

if(rc != GPG_ERR_NO_ERROR){

259

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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return -1;

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264

267

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/* Create new empty GPGME data buffer for the plaintext */

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rc = gpgme_data_new(&dh_plain);

269

if(rc != GPG_ERR_NO_ERROR){

267

if (rc != GPG_ERR_NO_ERROR){

270

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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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data buffer */

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rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);

279

if(rc != GPG_ERR_NO_ERROR){

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if (rc != GPG_ERR_NO_ERROR){

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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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if(debug){

281

if (debug){

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gpgme_decrypt_result_t result;

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result = gpgme_op_decrypt_result(mc->ctx);

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if(result == NULL){

284

if (result == NULL){

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fprintf(stderr, "gpgme_op_decrypt_result failed\n");

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} else {

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fprintf(stderr, "Unsupported algorithm: %s\n",

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}

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/* Seek back to the beginning of the GPGME plaintext data buffer */

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if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){

317

if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){

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perror("gpgme_data_seek");

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plaintext_length = -1;

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goto decrypt_end;

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plaintext_capacity = adjustbuffer(plaintext,

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(size_t)plaintext_length,

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plaintext_capacity);

330

if(plaintext_capacity == 0){

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if (plaintext_capacity == 0){

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perror("adjustbuffer");

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plaintext_length = -1;

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331

goto decrypt_end;

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ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

337

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BUFFER_SIZE);

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/* Print the data, if any */

339

if(ret == 0){

337

if (ret == 0){

340

338

/* EOF */

341

339

break;

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340

}

366

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return plaintext_length;

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}

368

366

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static const char * safer_gnutls_strerror(int value) {

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const char *ret = gnutls_strerror(value); /* Spurious warning from

371

-Wunreachable-code */

372

if(ret == NULL)

367

static const char * safer_gnutls_strerror (int value) {

368

const char *ret = gnutls_strerror (value); /* Spurious warning */

369

if (ret == NULL)

373

370

ret = "(unknown)";

374

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return ret;

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}

390

387

}

391

388

392

389

ret = gnutls_global_init();

393

if(ret != GNUTLS_E_SUCCESS) {

394

fprintf(stderr, "GnuTLS global_init: %s\n",

395

safer_gnutls_strerror(ret));

390

if (ret != GNUTLS_E_SUCCESS) {

391

fprintf (stderr, "GnuTLS global_init: %s\n",

392

safer_gnutls_strerror(ret));

396

393

return -1;

397

394

}

398

395

399

if(debug){

396

if (debug){

400

397

/* "Use a log level over 10 to enable all debugging options."

401

398

* - GnuTLS manual

402

399

*/

406

403

407

404

/* OpenPGP credentials */

408

405

gnutls_certificate_allocate_credentials(&mc->cred);

409

if(ret != GNUTLS_E_SUCCESS){

410

fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning

411

* from

412

* -Wunreachable-code

413

*/

414

safer_gnutls_strerror(ret));

415

gnutls_global_deinit();

406

if (ret != GNUTLS_E_SUCCESS){

407

fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious

408

warning */

409

safer_gnutls_strerror(ret));

410

gnutls_global_deinit ();

416

411

return -1;

417

412

}

418

413

425

420

ret = gnutls_certificate_set_openpgp_key_file

426

421

(mc->cred, pubkeyfilename, seckeyfilename,

427

422

GNUTLS_OPENPGP_FMT_BASE64);

428

if(ret != GNUTLS_E_SUCCESS) {

423

if (ret != GNUTLS_E_SUCCESS) {

429

424

fprintf(stderr,

430

425

"Error[%d] while reading the OpenPGP key pair ('%s',"

431

426

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

436

431

437

432

/* GnuTLS server initialization */

438

433

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));

434

if (ret != GNUTLS_E_SUCCESS) {

435

fprintf (stderr, "Error in GnuTLS DH parameter initialization:"

436

" %s\n", safer_gnutls_strerror(ret));

442

437

goto globalfail;

443

438

}

444

439

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));

440

if (ret != GNUTLS_E_SUCCESS) {

441

fprintf (stderr, "Error in GnuTLS prime generation: %s\n",

442

safer_gnutls_strerror(ret));

448

443

goto globalfail;

449

444

}

450

445

465

460

int ret;

466

461

/* GnuTLS session creation */

467

462

ret = gnutls_init(session, GNUTLS_SERVER);

468

if(ret != GNUTLS_E_SUCCESS){

463

if (ret != GNUTLS_E_SUCCESS){

469

464

fprintf(stderr, "Error in GnuTLS session initialization: %s\n",

470

465

safer_gnutls_strerror(ret));

471

466

}

473

468

{

474

469

const char *err;

475

470

ret = gnutls_priority_set_direct(*session, mc->priority, &err);

476

if(ret != GNUTLS_E_SUCCESS) {

471

if (ret != GNUTLS_E_SUCCESS) {

477

472

fprintf(stderr, "Syntax error at: %s\n", err);

478

473

fprintf(stderr, "GnuTLS error: %s\n",

479

474

safer_gnutls_strerror(ret));

480

gnutls_deinit(*session);

475

gnutls_deinit (*session);

481

476

return -1;

482

477

}

483

478

}

484

479

485

480

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

486

481

mc->cred);

487

if(ret != GNUTLS_E_SUCCESS) {

482

if (ret != GNUTLS_E_SUCCESS) {

488

483

fprintf(stderr, "Error setting GnuTLS credentials: %s\n",

489

484

safer_gnutls_strerror(ret));

490

gnutls_deinit(*session);

485

gnutls_deinit (*session);

491

486

return -1;

492

487

}

493

488

494

489

/* ignore client certificate if any. */

495

gnutls_certificate_server_set_request(*session,

496

GNUTLS_CERT_IGNORE);

490

gnutls_certificate_server_set_request (*session,

491

GNUTLS_CERT_IGNORE);

497

492

498

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

493

gnutls_dh_set_prime_bits (*session, mc->dh_bits);

499

494

500

495

return 0;

501

496

}

509

504

AvahiIfIndex if_index,

510

505

mandos_context *mc){

511

506

int ret, tcp_sd;

512

ssize_t sret;

513

507

union { struct sockaddr in; struct sockaddr_in6 in6; } to;

514

508

char *buffer = NULL;

515

509

char *decrypted_buffer;

521

515

char interface[IF_NAMESIZE];

522

516

gnutls_session_t session;

523

517

524

ret = init_gnutls_session(mc, &session);

525

if(ret != 0){

518

ret = init_gnutls_session (mc, &session);

519

if (ret != 0){

526

520

return -1;

527

521

}

528

522

550

544

/* It would be nice to have a way to detect if we were passed an

551

545

IPv4 address here. Now we assume an IPv6 address. */

552

546

ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);

553

if(ret < 0 ){

547

if (ret < 0 ){

554

548

perror("inet_pton");

555

549

return -1;

556

550

}

558

552

fprintf(stderr, "Bad address: %s\n", ip);

559

553

return -1;

560

554

}

561

to.in6.sin6_port = htons(port); /* Spurious warnings from

562

-Wconversion and

563

-Wunreachable-code */

555

to.in6.sin6_port = htons(port); /* Spurious warning */

564

556

565

557

to.in6.sin6_scope_id = (uint32_t)if_index;

566

558

579

571

}

580

572

581

573

ret = connect(tcp_sd, &to.in, sizeof(to));

582

if(ret < 0){

574

if (ret < 0){

583

575

perror("connect");

584

576

return -1;

585

577

}

586

578

587

579

const char *out = mandos_protocol_version;

588

580

written = 0;

589

while(true){

581

while (true){

590

582

size_t out_size = strlen(out);

591

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

583

ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

592

584

out_size - written));

593

if(ret == -1){

585

if (ret == -1){

594

586

perror("write");

595

587

retval = -1;

596

588

goto mandos_end;

599

591

if(written < out_size){

600

592

continue;

601

593

} else {

602

if(out == mandos_protocol_version){

594

if (out == mandos_protocol_version){

603

595

written = 0;

604

596

out = "\r\n";

605

597

} else {

612

604

fprintf(stderr, "Establishing TLS session with %s\n", ip);

613

605

}

614

606

615

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

607

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

616

608

617

609

do{

618

ret = gnutls_handshake(session);

610

ret = gnutls_handshake (session);

619

611

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

620

612

621

if(ret != GNUTLS_E_SUCCESS){

613

if (ret != GNUTLS_E_SUCCESS){

622

614

if(debug){

623

615

fprintf(stderr, "*** GnuTLS Handshake failed ***\n");

624

gnutls_perror(ret);

616

gnutls_perror (ret);

625

617

}

626

618

retval = -1;

627

619

goto mandos_end;

637

629

while(true){

638

630

buffer_capacity = adjustbuffer(&buffer, buffer_length,

639

631

buffer_capacity);

640

if(buffer_capacity == 0){

632

if (buffer_capacity == 0){

641

633

perror("adjustbuffer");

642

634

retval = -1;

643

635

goto mandos_end;

644

636

}

645

637

646

sret = gnutls_record_recv(session, buffer+buffer_length,

647

BUFFER_SIZE);

648

if(sret == 0){

638

ret = gnutls_record_recv(session, buffer+buffer_length,

639

BUFFER_SIZE);

640

if (ret == 0){

649

641

break;

650

642

}

651

if(sret < 0){

652

switch(sret){

643

if (ret < 0){

644

switch(ret){

653

645

case GNUTLS_E_INTERRUPTED:

654

646

case GNUTLS_E_AGAIN:

655

647

break;

656

648

case GNUTLS_E_REHANDSHAKE:

657

649

do{

658

ret = gnutls_handshake(session);

650

ret = gnutls_handshake (session);

659

651

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

660

if(ret < 0){

652

if (ret < 0){

661

653

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

662

gnutls_perror(ret);

654

gnutls_perror (ret);

663

655

retval = -1;

664

656

goto mandos_end;

665

657

}

668

660

fprintf(stderr, "Unknown error while reading data from"

669

661

" encrypted session with Mandos server\n");

670

662

retval = -1;

671

gnutls_bye(session, GNUTLS_SHUT_RDWR);

663

gnutls_bye (session, GNUTLS_SHUT_RDWR);

672

664

goto mandos_end;

673

665

}

674

666

} else {

675

buffer_length += (size_t) sret;

667

buffer_length += (size_t) ret;

676

668

}

677

669

}

678

670

680

672

fprintf(stderr, "Closing TLS session\n");

681

673

}

682

674

683

gnutls_bye(session, GNUTLS_SHUT_RDWR);

675

gnutls_bye (session, GNUTLS_SHUT_RDWR);

684

676

685

if(buffer_length > 0){

677

if (buffer_length > 0){

686

678

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

687

679

buffer_length,

688

680

&decrypted_buffer);

689

if(decrypted_buffer_size >= 0){

681

if (decrypted_buffer_size >= 0){

690

682

written = 0;

691

683

while(written < (size_t) decrypted_buffer_size){

692

ret = (int)fwrite(decrypted_buffer + written, 1,

693

(size_t)decrypted_buffer_size - written,

694

stdout);

684

ret = (int)fwrite (decrypted_buffer + written, 1,

685

(size_t)decrypted_buffer_size - written,

686

stdout);

695

687

if(ret == 0 and ferror(stdout)){

696

688

if(debug){

697

689

fprintf(stderr, "Error writing encrypted data: %s\n",

714

706

715

707

mandos_end:

716

708

free(buffer);

717

ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));

709

ret = TEMP_FAILURE_RETRY(close(tcp_sd));

718

710

if(ret == -1){

719

711

perror("close");

720

712

}

721

gnutls_deinit(session);

713

gnutls_deinit (session);

722

714

return retval;

723

715

}

724

716

742

734

/* Called whenever a service has been resolved successfully or

743

735

timed out */

744

736

745

switch(event) {

737

switch (event) {

746

738

default:

747

739

case AVAHI_RESOLVER_FAILURE:

748

740

fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"

756

748

avahi_address_snprint(ip, sizeof(ip), address);

757

749

if(debug){

758

750

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"

759

PRIdMAX ") on port %" PRIu16 "\n", name, host_name,

760

ip, (intmax_t)interface, port);

751

PRIu16 ") on port %d\n", name, host_name, ip,

752

interface, port);

761

753

}

762

754

int ret = start_mandos_communication(ip, port, interface, mc);

763

if(ret == 0){

755

if (ret == 0){

764

756

avahi_simple_poll_quit(mc->simple_poll);

765

757

}

766

758

}

784

776

/* Called whenever a new services becomes available on the LAN or

785

777

is removed from the LAN */

786

778

787

switch(event) {

779

switch (event) {

788

780

default:

789

781

case AVAHI_BROWSER_FAILURE:

790

782

799

791

the callback function is called the Avahi server will free the

800

792

resolver for us. */

801

793

802

if(!(avahi_s_service_resolver_new(mc->server, interface,

794

if (!(avahi_s_service_resolver_new(mc->server, interface,

803

795

protocol, name, type, domain,

804

796

AVAHI_PROTO_INET6, 0,

805

797

resolve_callback, mc)))

823

815

AvahiSServiceBrowser *sb = NULL;

824

816

int error;

825

817

int ret;

826

intmax_t tmpmax;

827

int numchars;

828

818

int exitcode = EXIT_SUCCESS;

829

819

const char *interface = "eth0";

830

820

struct ifreq network;

833

823

gid_t gid;

834

824

char *connect_to = NULL;

835

825

char tempdir[] = "/tmp/mandosXXXXXX";

836

bool tempdir_created = false;

837

826

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

838

827

const char *seckey = PATHDIR "/" SECKEY;

839

828

const char *pubkey = PATHDIR "/" PUBKEY;

841

830

mandos_context mc = { .simple_poll = NULL, .server = NULL,

842

831

.dh_bits = 1024, .priority = "SECURE256"

843

832

":!CTYPE-X.509:+CTYPE-OPENPGP" };

844

bool gnutls_initialized = false;

845

bool gpgme_initialized = false;

846

double delay = 2.5;

833

bool gnutls_initalized = false;

834

bool gpgme_initalized = false;

847

835

848

836

{

849

837

struct argp_option options[] = {

875

863

.arg = "STRING",

876

864

.doc = "GnuTLS priority string for the TLS handshake",

877

865

.group = 1 },

878

{ .name = "delay", .key = 131,

879

.arg = "SECONDS",

880

.doc = "Maximum delay to wait for interface startup",

881

.group = 2 },

882

866

{ .name = NULL }

883

867

};

884

868

885

error_t parse_opt(int key, char *arg,

886

struct argp_state *state) {

887

switch(key) {

869

error_t parse_opt (int key, char *arg,

870

struct argp_state *state) {

871

/* Get the INPUT argument from `argp_parse', which we know is

872

a pointer to our plugin list pointer. */

873

switch (key) {

888

874

case 128: /* --debug */

889

875

debug = true;

890

876

break;

901

887

pubkey = arg;

902

888

break;

903

889

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");

890

errno = 0;

891

mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);

892

if (errno){

893

perror("strtol");

908

894

exit(EXIT_FAILURE);

909

895

}

910

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

911

896

break;

912

897

case 130: /* --priority */

913

898

mc.priority = arg;

914

899

break;

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");

919

exit(EXIT_FAILURE);

920

}

921

break;

922

900

case ARGP_KEY_ARG:

923

argp_usage(state);

901

argp_usage (state);

924

902

case ARGP_KEY_END:

925

903

break;

926

904

default:

933

911

.args_doc = "",

934

912

.doc = "Mandos client -- Get and decrypt"

935

913

" passwords from a Mandos server" };

936

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

937

if(ret == ARGP_ERR_UNKNOWN){

914

ret = argp_parse (&argp, argc, argv, 0, 0, NULL);

915

if (ret == ARGP_ERR_UNKNOWN){

938

916

fprintf(stderr, "Unknown error while parsing arguments\n");

939

917

exitcode = EXIT_FAILURE;

940

918

goto end;

943

921

944

922

/* If the interface is down, bring it up */

945

923

{

946

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

947

messages to mess up the prompt */

948

ret = klogctl(8, NULL, 5);

949

if(ret == -1){

950

perror("klogctl");

951

}

952

953

924

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

954

925

if(sd < 0) {

955

926

perror("socket");

956

927

exitcode = EXIT_FAILURE;

957

ret = klogctl(7, NULL, 0);

958

if(ret == -1){

959

perror("klogctl");

960

}

961

928

goto end;

962

929

}

963

930

strcpy(network.ifr_name, interface);

964

931

ret = ioctl(sd, SIOCGIFFLAGS, &network);

965

932

if(ret == -1){

966

933

perror("ioctl SIOCGIFFLAGS");

967

ret = klogctl(7, NULL, 0);

968

if(ret == -1){

969

perror("klogctl");

970

}

971

934

exitcode = EXIT_FAILURE;

972

935

goto end;

973

936

}

977

940

if(ret == -1){

978

941

perror("ioctl SIOCSIFFLAGS");

979

942

exitcode = EXIT_FAILURE;

980

ret = klogctl(7, NULL, 0);

981

if(ret == -1){

982

perror("klogctl");

983

}

984

943

goto end;

985

944

}

986

945

}

987

/* sleep checking until interface is running */

988

for(int i=0; i < delay * 4; i++){

989

ret = ioctl(sd, SIOCGIFFLAGS, &network);

990

if(ret == -1){

991

perror("ioctl SIOCGIFFLAGS");

992

} else if(network.ifr_flags & IFF_RUNNING){

993

break;

994

}

995

struct timespec sleeptime = { .tv_nsec = 250000000 };

996

nanosleep(&sleeptime, NULL);

997

}

998

ret = (int)TEMP_FAILURE_RETRY(close(sd));

946

ret = TEMP_FAILURE_RETRY(close(sd));

999

947

if(ret == -1){

1000

948

perror("close");

1001

949

}

1002

/* Restores kernel loglevel to default */

1003

ret = klogctl(7, NULL, 0);

1004

if(ret == -1){

1005

perror("klogctl");

1006

}

1007

950

}

1008

951

1009

952

uid = getuid();

1010

953

gid = getgid();

1011

954

955

ret = setuid(uid);

956

if (ret == -1){

957

perror("setuid");

958

}

959

1012

960

setgid(gid);

1013

if(ret == -1){

961

if (ret == -1){

1014

962

perror("setgid");

1015

963

}

1016

964

1017

ret = setuid(uid);

1018

if(ret == -1){

1019

perror("setuid");

1020

}

1021

1022

965

ret = init_gnutls_global(&mc, pubkey, seckey);

1023

if(ret == -1){

966

if (ret == -1){

1024

967

fprintf(stderr, "init_gnutls_global failed\n");

1025

968

exitcode = EXIT_FAILURE;

1026

969

goto end;

1027

970

} else {

1028

gnutls_initialized = true;

971

gnutls_initalized = true;

1029

972

}

1030

973

1031

974

if(mkdtemp(tempdir) == NULL){

1032

975

perror("mkdtemp");

976

tempdir[0] = '\0';

1033

977

goto end;

1034

978

}

1035

tempdir_created = true;

1036

979

1037

980

if(not init_gpgme(&mc, pubkey, seckey, tempdir)){

1038

fprintf(stderr, "init_gpgme failed\n");

981

fprintf(stderr, "gpgme_initalized failed\n");

1039

982

exitcode = EXIT_FAILURE;

1040

983

goto end;

1041

984

} else {

1042

gpgme_initialized = true;

985

gpgme_initalized = true;

1043

986

}

1044

987

1045

988

if_index = (AvahiIfIndex) if_nametoindex(interface);

1046

989

if(if_index == 0){

1047

990

fprintf(stderr, "No such interface: \"%s\"\n", interface);

1048

exitcode = EXIT_FAILURE;

1049

goto end;

991

exit(EXIT_FAILURE);

1050

992

}

1051

993

1052

994

if(connect_to != NULL){

1058

1000

exitcode = EXIT_FAILURE;

1059

1001

goto end;

1060

1002

}

1061

uint16_t port;

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");

1003

errno = 0;

1004

uint16_t port = (uint16_t) strtol(address+1, NULL, 10);

1005

if(errno){

1006

perror("Bad port number");

1066

1007

exitcode = EXIT_FAILURE;

1067

1008

goto end;

1068

1009

}

1069

port = (uint16_t)tmpmax;

1070

1010

*address = '\0';

1071

1011

address = connect_to;

1072

1012

ret = start_mandos_communication(address, port, if_index, &mc);

1078

1018

goto end;

1079

1019

}

1080

1020

1081

if(not debug){

1021

if (not debug){

1082

1022

avahi_set_log_function(empty_log);

1083

1023

}

1084

1024

1087

1027

1088

1028

/* Allocate main Avahi loop object */

1089

1029

mc.simple_poll = avahi_simple_poll_new();

1090

if(mc.simple_poll == NULL) {

1030

if (mc.simple_poll == NULL) {

1091

1031

fprintf(stderr, "Avahi: Failed to create simple poll"

1092

1032

" object.\n");

1093

1033

exitcode = EXIT_FAILURE;

1113

1053

}

1114

1054

1115

1055

/* Check if creating the Avahi server object succeeded */

1116

if(mc.server == NULL) {

1056

if (mc.server == NULL) {

1117

1057

fprintf(stderr, "Failed to create Avahi server: %s\n",

1118

1058

avahi_strerror(error));

1119

1059

exitcode = EXIT_FAILURE;

1125

1065

AVAHI_PROTO_INET6,

1126

1066

"_mandos._tcp", NULL, 0,

1127

1067

browse_callback, &mc);

1128

if(sb == NULL) {

1068

if (sb == NULL) {

1129

1069

fprintf(stderr, "Failed to create service browser: %s\n",

1130

1070

avahi_strerror(avahi_server_errno(mc.server)));

1131

1071

exitcode = EXIT_FAILURE;

1134

1074

1135

1075

/* Run the main loop */

1136

1076

1137

if(debug){

1077

if (debug){

1138

1078

fprintf(stderr, "Starting Avahi loop search\n");

1139

1079

}

1140

1080

1141

1081

avahi_simple_poll_loop(mc.simple_poll);

1142

1082

1143

1083

end:

1144

1084

1145

if(debug){

1085

if (debug){

1146

1086

fprintf(stderr, "%s exiting\n", argv[0]);

1147

1087

}

1148

1088

1149

1089

/* Cleanup things */

1150

if(sb != NULL)

1090

if (sb != NULL)

1151

1091

avahi_s_service_browser_free(sb);

1152

1092

1153

if(mc.server != NULL)

1093

if (mc.server != NULL)

1154

1094

avahi_server_free(mc.server);

1155

1095

1156

if(mc.simple_poll != NULL)

1096

if (mc.simple_poll != NULL)

1157

1097

avahi_simple_poll_free(mc.simple_poll);

1158

1098

1159

if(gnutls_initialized){

1099

if (gnutls_initalized){

1160

1100

gnutls_certificate_free_credentials(mc.cred);

1161

gnutls_global_deinit();

1101

gnutls_global_deinit ();

1162

1102

gnutls_dh_params_deinit(mc.dh_params);

1163

1103

}

1164

1104

1165

if(gpgme_initialized){

1105

if(gpgme_initalized){

1166

1106

gpgme_release(mc.ctx);

1167

1107

}

1168

1108

1169

1109

/* Removes the temp directory used by GPGME */

1170

if(tempdir_created){

1110

if(tempdir[0] != '\0'){

1171

1111

DIR *d;

1172

1112

struct dirent *direntry;

1173

1113

d = opendir(tempdir);

1174

1114

if(d == NULL){

1175

if(errno != ENOENT){

1176

perror("opendir");

1177

}

1115

perror("opendir");

1178

1116

} else {

1179

1117

while(true){

1180

1118

direntry = readdir(d);

1181

1119

if(direntry == NULL){

1182

1120

break;

1183

1121

}

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'))){

1189

continue;

1190

}

1191

char *fullname = NULL;

1192

ret = asprintf(&fullname, "%s/%s", tempdir,

1193

direntry->d_name);

1194

if(ret < 0){

1195

perror("asprintf");

1196

continue;

1197

}

1198

ret = remove(fullname);

1199

if(ret == -1){

1200

fprintf(stderr, "remove(\"%s\"): %s\n", fullname,

1201

strerror(errno));

1202

}

1203

free(fullname);

1122

if (direntry->d_type == DT_REG){

1123

char *fullname = NULL;

1124

ret = asprintf(&fullname, "%s/%s", tempdir,

1125

direntry->d_name);

1126

if(ret < 0){

1127

perror("asprintf");

1128

continue;

1129

}

1130

ret = unlink(fullname);

1131

if(ret == -1){

1132

fprintf(stderr, "unlink(\"%s\"): %s",

1133

fullname, strerror(errno));

1134

}

1135

free(fullname);

1136

}

1204

1137

}

1205

1138

closedir(d);

1206

1139

}

1207

1140

ret = rmdir(tempdir);

1208

if(ret == -1 and errno != ENOENT){

1141

if(ret == -1){

1209

1142

perror("rmdir");

1210

1143

}

1211

1144

}

1212

1145

1213

1146

return exitcode;

1214

1147

}