/mandos/trunk : revision 24.1.186

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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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* along with this program. If not, see

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* <http://www.gnu.org/licenses/>.

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*

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* Contact the authors at <mandos@recompile.se>.

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* Contact the authors at <mandos@fukt.bsnet.se>.

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*/

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/* Needed by GPGME, specifically gpgme_data_seek() */

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#include <stdio.h> /* fprintf(), stderr, fwrite(),

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stdout, ferror(), remove() */

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#include <stdint.h> /* uint16_t, uint32_t, intptr_t */

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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, srand(),

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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#include <sys/stat.h> /* open(), S_ISREG */

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#include <sys/stat.h> /* open() */

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#include <sys/socket.h> /* socket(), struct sockaddr_in6,

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inet_pton(), connect() */

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

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*/

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

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strtoimax() */

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#include <assert.h> /* assert() */

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#include <errno.h> /* perror(), errno,

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program_invocation_short_name */

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#include <time.h> /* nanosleep(), time(), sleep() */

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*/

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#include <unistd.h> /* close(), SEEK_SET, off_t, write(),

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getuid(), getgid(), seteuid(),

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setgid(), pause(), _exit() */

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setgid(), pause() */

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#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */

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#include <iso646.h> /* not, or, and */

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

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raise() */

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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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#include <sys/wait.h> /* waitpid(), WIFEXITED(),

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WEXITSTATUS(), WTERMSIG() */

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#include <grp.h> /* setgroups() */

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#include <argz.h> /* argz_add_sep(), argz_next(),

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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

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init_gnutls_session(),

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109

GNUTLS_* */

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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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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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#include <gpgme.h> /* All GPGME types, constants and

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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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#define HOOKDIR "/lib/mandos/network-hooks.d"

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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const char *argp_program_version = "mandos-client " VERSION;

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const char *argp_program_bug_address = "<mandos@recompile.se>";

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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

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static const char sys_class_net[] = "/sys/class/net";

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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/* Doubly linked list that need to be circularly linked when used */

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typedef struct server{

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136

const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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/* Used for passing in values through the Avahi callback functions */

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typedef struct {

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AvahiSimplePoll *simple_poll;

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148

AvahiServer *server;

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149

gnutls_certificate_credentials_t cred;

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150

unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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/* global context so signal handler can reach it*/

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

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.dh_bits = 1024, .priority = "SECURE256"

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":!CTYPE-X.509:+CTYPE-OPENPGP",

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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165

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/* Function to use when printing errors */

175

167

void perror_plus(const char *print_text){

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int e = errno;

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168

fprintf(stderr, "Mandos plugin %s: ",

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169

program_invocation_short_name);

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errno = e;

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perror(print_text);

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171

}

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__attribute__((format (gnu_printf, 2, 3)))

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int fprintf_plus(FILE *stream, const char *format, ...){

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va_list ap;

186

va_start (ap, format);

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188

TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",

189

program_invocation_short_name));

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return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

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}

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193

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/*

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* Make additional room in "buffer" for at least BUFFER_SIZE more

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* bytes. "buffer_capacity" is how much is currently allocated,

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* "buffer_length" is how much is already used.

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*/

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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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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182

if(buffer == NULL){

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188

}

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/* Add server to set of servers to retry periodically */

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bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,

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int af, server **current_server){

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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int ret;

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server *new_server = malloc(sizeof(server));

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if(new_server == NULL){

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197

perror_plus("malloc");

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return false;

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return -1;

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}

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*new_server = (server){ .ip = strdup(ip),

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

224

205

perror_plus("strdup");

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return false;

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return -1;

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207

}

227

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/* Special case of first server */

228

if(*current_server == NULL){

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if (mc.current_server == NULL){

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new_server->next = new_server;

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211

new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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/* Place the new server last in the list */

233

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} else {

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new_server->next = *current_server;

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new_server->prev = (*current_server)->prev;

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new_server->next = mc.current_server;

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new_server->prev = mc.current_server->prev;

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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mc.current_server->prev = new_server;

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}

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ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);

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ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);

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221

if(ret == -1){

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222

perror_plus("clock_gettime");

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return false;

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return -1;

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}

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return true;

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return 0;

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226

}

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227

247

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/*

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* Initialize GPGME.

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*/

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static bool init_gpgme(const char *seckey, const char *pubkey,

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const char *tempdir, mandos_context *mc){

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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233

gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

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

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239

*/

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

270

252

if(rc != GPG_ERR_NO_ERROR){

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fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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rc = gpgme_op_import(mc.ctx, pgp_data);

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if(rc != GPG_ERR_NO_ERROR){

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fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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}

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if(debug){

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fprintf_plus(stderr, "Initializing GPGME\n");

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fprintf(stderr, "Initializing GPGME\n");

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}

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/* Init GPGME */

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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_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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284

}

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285

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/* Set GPGME home directory for the OpenPGP engine only */

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rc = gpgme_get_engine_info(&engine_info);

306

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if(rc != GPG_ERR_NO_ERROR){

307

fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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291

return false;

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292

}

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while(engine_info != NULL){

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engine_info = engine_info->next;

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300

}

319

301

if(engine_info == NULL){

320

fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",

321

tempdir);

302

fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);

322

303

return false;

323

304

}

324

305

325

306

/* Create new GPGME "context" */

326

rc = gpgme_new(&(mc->ctx));

307

rc = gpgme_new(&(mc.ctx));

327

308

if(rc != GPG_ERR_NO_ERROR){

328

fprintf_plus(stderr, "Mandos plugin mandos-client: "

329

"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),

330

gpgme_strerror(rc));

309

fprintf(stderr, "bad gpgme_new: %s: %s\n",

310

gpgme_strsource(rc), gpgme_strerror(rc));

331

311

return false;

332

312

}

333

313

344

324

*/

345

325

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

326

size_t crypto_size,

347

char **plaintext,

348

mandos_context *mc){

327

char **plaintext){

349

328

gpgme_data_t dh_crypto, dh_plain;

350

329

gpgme_error_t rc;

351

330

ssize_t ret;

353

332

ssize_t plaintext_length = 0;

354

333

355

334

if(debug){

356

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

335

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

357

336

}

358

337

359

338

/* Create new GPGME data buffer from memory cryptotext */

360

339

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

361

340

0);

362

341

if(rc != GPG_ERR_NO_ERROR){

363

fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",

364

gpgme_strsource(rc), gpgme_strerror(rc));

342

fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",

343

gpgme_strsource(rc), gpgme_strerror(rc));

365

344

return -1;

366

345

}

367

346

368

347

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

369

348

rc = gpgme_data_new(&dh_plain);

370

349

if(rc != GPG_ERR_NO_ERROR){

371

fprintf_plus(stderr, "Mandos plugin mandos-client: "

372

"bad gpgme_data_new: %s: %s\n",

373

gpgme_strsource(rc), gpgme_strerror(rc));

350

fprintf(stderr, "bad gpgme_data_new: %s: %s\n",

351

gpgme_strsource(rc), gpgme_strerror(rc));

374

352

gpgme_data_release(dh_crypto);

375

353

return -1;

376

354

}

377

355

378

356

/* Decrypt data from the cryptotext data buffer to the plaintext

379

357

data buffer */

380

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

358

rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);

381

359

if(rc != GPG_ERR_NO_ERROR){

382

fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",

383

gpgme_strsource(rc), gpgme_strerror(rc));

360

fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",

361

gpgme_strsource(rc), gpgme_strerror(rc));

384

362

plaintext_length = -1;

385

363

if(debug){

386

364

gpgme_decrypt_result_t result;

387

result = gpgme_op_decrypt_result(mc->ctx);

365

result = gpgme_op_decrypt_result(mc.ctx);

388

366

if(result == NULL){

389

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

367

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

390

368

} else {

391

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

392

result->unsupported_algorithm);

393

fprintf_plus(stderr, "Wrong key usage: %u\n",

394

result->wrong_key_usage);

369

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

370

result->unsupported_algorithm);

371

fprintf(stderr, "Wrong key usage: %u\n",

372

result->wrong_key_usage);

395

373

if(result->file_name != NULL){

396

fprintf_plus(stderr, "File name: %s\n", result->file_name);

374

fprintf(stderr, "File name: %s\n", result->file_name);

397

375

}

398

376

gpgme_recipient_t recipient;

399

377

recipient = result->recipients;

400

378

while(recipient != NULL){

401

fprintf_plus(stderr, "Public key algorithm: %s\n",

402

gpgme_pubkey_algo_name

403

(recipient->pubkey_algo));

404

fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);

405

fprintf_plus(stderr, "Secret key available: %s\n",

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

379

fprintf(stderr, "Public key algorithm: %s\n",

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

382

fprintf(stderr, "Secret key available: %s\n",

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

408

385

recipient = recipient->next;

409

386

}

410

387

}

413

390

}

414

391

415

392

if(debug){

416

fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");

393

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

417

394

}

418

395

419

396

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

426

403

*plaintext = NULL;

427

404

while(true){

428

405

plaintext_capacity = incbuffer(plaintext,

429

(size_t)plaintext_length,

430

plaintext_capacity);

406

(size_t)plaintext_length,

407

plaintext_capacity);

431

408

if(plaintext_capacity == 0){

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

435

412

}

436

413

437

414

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

450

427

}

451

428

452

429

if(debug){

453

fprintf_plus(stderr, "Decrypted password is: ");

430

fprintf(stderr, "Decrypted password is: ");

454

431

for(ssize_t i = 0; i < plaintext_length; i++){

455

432

fprintf(stderr, "%02hhX ", (*plaintext)[i]);

456

433

}

468

445

}

469

446

470

447

static const char * safer_gnutls_strerror(int value){

471

const char *ret = gnutls_strerror(value);

448

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

449

-Wunreachable-code */

472

450

if(ret == NULL)

473

451

ret = "(unknown)";

474

452

return ret;

477

455

/* GnuTLS log function callback */

478

456

static void debuggnutls(__attribute__((unused)) int level,

479

457

const char* string){

480

fprintf_plus(stderr, "GnuTLS: %s", string);

458

fprintf(stderr, "GnuTLS: %s", string);

481

459

}

482

460

483

461

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename,

485

mandos_context *mc){

462

const char *seckeyfilename){

486

463

int ret;

487

464

488

465

if(debug){

489

fprintf_plus(stderr, "Initializing GnuTLS\n");

466

fprintf(stderr, "Initializing GnuTLS\n");

490

467

}

491

468

492

469

ret = gnutls_global_init();

493

470

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

496

473

return -1;

497

474

}

498

475

505

482

}

506

483

507

484

/* OpenPGP credentials */

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

509

486

if(ret != GNUTLS_E_SUCCESS){

510

fprintf_plus(stderr, "GnuTLS memory error: %s\n",

511

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

512

489

gnutls_global_deinit();

513

490

return -1;

514

491

}

515

492

516

493

if(debug){

517

fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"

518

" secret key %s as GnuTLS credentials\n",

519

pubkeyfilename,

520

seckeyfilename);

494

fprintf(stderr, "Attempting to use OpenPGP public key %s and"

495

" secret key %s as GnuTLS credentials\n", pubkeyfilename,

496

seckeyfilename);

521

497

}

522

498

523

499

ret = gnutls_certificate_set_openpgp_key_file

524

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

525

501

GNUTLS_OPENPGP_FMT_BASE64);

526

502

if(ret != GNUTLS_E_SUCCESS){

527

fprintf_plus(stderr,

528

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

529

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

530

fprintf_plus(stderr, "The GnuTLS error is: %s\n",

531

safer_gnutls_strerror(ret));

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

532

508

goto globalfail;

533

509

}

534

510

535

511

/* GnuTLS server initialization */

536

ret = gnutls_dh_params_init(&mc->dh_params);

512

ret = gnutls_dh_params_init(&mc.dh_params);

537

513

if(ret != GNUTLS_E_SUCCESS){

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

514

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

515

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

541

516

goto globalfail;

542

517

}

543

ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);

518

ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);

544

519

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

520

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

521

safer_gnutls_strerror(ret));

547

522

goto globalfail;

548

523

}

549

524

550

gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

551

526

552

527

return 0;

553

528

554

529

globalfail:

555

530

556

gnutls_certificate_free_credentials(mc->cred);

531

gnutls_certificate_free_credentials(mc.cred);

557

532

gnutls_global_deinit();

558

gnutls_dh_params_deinit(mc->dh_params);

533

gnutls_dh_params_deinit(mc.dh_params);

559

534

return -1;

560

535

}

561

536

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

564

538

int ret;

565

539

/* GnuTLS session creation */

566

540

do {

570

544

}

571

545

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

572

546

if(ret != GNUTLS_E_SUCCESS){

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

547

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

548

safer_gnutls_strerror(ret));

576

549

}

577

550

578

551

{

579

552

const char *err;

580

553

do {

581

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

554

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

582

555

if(quit_now){

583

556

gnutls_deinit(*session);

584

557

return -1;

585

558

}

586

559

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

587

560

if(ret != GNUTLS_E_SUCCESS){

588

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

589

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

590

safer_gnutls_strerror(ret));

561

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

562

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

563

safer_gnutls_strerror(ret));

591

564

gnutls_deinit(*session);

592

565

return -1;

593

566

}

595

568

596

569

do {

597

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

598

mc->cred);

571

mc.cred);

599

572

if(quit_now){

600

573

gnutls_deinit(*session);

601

574

return -1;

602

575

}

603

576

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

604

577

if(ret != GNUTLS_E_SUCCESS){

605

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

606

safer_gnutls_strerror(ret));

578

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

579

safer_gnutls_strerror(ret));

607

580

gnutls_deinit(*session);

608

581

return -1;

609

582

}

611

584

/* ignore client certificate if any. */

612

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

586

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

615

588

616

589

return 0;

617

590

}

621

594

__attribute__((unused)) const char *txt){}

622

595

623

596

/* Called when a Mandos server is found */

624

static int start_mandos_communication(const char *ip, in_port_t port,

597

static int start_mandos_communication(const char *ip, uint16_t port,

625

598

AvahiIfIndex if_index,

626

int af, mandos_context *mc){

599

int af){

627

600

int ret, tcp_sd = -1;

628

601

ssize_t sret;

629

602

union {

654

627

pf = PF_INET;

655

628

break;

656

629

default:

657

fprintf_plus(stderr, "Bad address family: %d\n", af);

630

fprintf(stderr, "Bad address family: %d\n", af);

658

631

errno = EINVAL;

659

632

return -1;

660

633

}

661

634

662

/* If the interface is specified and we have a list of interfaces */

663

if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){

664

/* Check if the interface is one of the interfaces we are using */

665

bool match = false;

666

{

667

char *interface = NULL;

668

while((interface=argz_next(mc->interfaces, mc->interfaces_size,

669

interface))){

670

if(if_nametoindex(interface) == (unsigned int)if_index){

671

match = true;

672

break;

673

}

674

}

675

}

676

if(not match){

677

/* This interface does not match any in the list, so we don't

678

connect to the server */

679

if(debug){

680

char interface[IF_NAMESIZE];

681

if(if_indextoname((unsigned int)if_index, interface) == NULL){

682

perror_plus("if_indextoname");

683

} else {

684

fprintf_plus(stderr, "Skipping server on non-used interface"

685

" \"%s\"\n",

686

if_indextoname((unsigned int)if_index,

687

interface));

688

}

689

}

690

return -1;

691

}

692

}

693

694

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

695

636

if(ret != 0){

696

637

return -1;

697

638

}

698

639

699

640

if(debug){

700

fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"

701

PRIuMAX "\n", ip, (uintmax_t)port);

641

fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16

642

"\n", ip, port);

702

643

}

703

644

704

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

730

671

}

731

672

if(ret == 0){

732

673

int e = errno;

733

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

674

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

734

675

errno = e;

735

676

goto mandos_end;

736

677

}

737

678

if(af == AF_INET6){

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

743

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

744

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

684

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and

685

-Wunreachable-code*/

748

686

if(if_index == AVAHI_IF_UNSPEC){

749

fprintf_plus(stderr, "An IPv6 link-local address is"

750

" incomplete without a network interface\n");

687

fprintf(stderr, "An IPv6 link-local address is incomplete"

688

" without a network interface\n");

751

689

errno = EINVAL;

752

690

goto mandos_end;

753

691

}

755

693

to.in6.sin6_scope_id = (uint32_t)if_index;

756

694

}

757

695

} else {

758

to.in.sin_port = htons(port);

696

to.in.sin_port = htons(port); /* Spurious warnings from

697

-Wconversion and

698

-Wunreachable-code */

759

699

}

760

700

761

701

if(quit_now){

769

709

if(if_indextoname((unsigned int)if_index, interface) == NULL){

770

710

perror_plus("if_indextoname");

771

711

} else {

772

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX

773

"\n", ip, interface, (uintmax_t)port);

712

fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",

713

ip, interface, port);

774

714

}

775

715

} else {

776

fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",

777

ip, (uintmax_t)port);

716

fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,

717

port);

778

718

}

779

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

780

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

790

730

perror_plus("inet_ntop");

791

731

} else {

792

732

if(strcmp(addrstr, ip) != 0){

793

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

733

fprintf(stderr, "Canonical address form: %s\n", addrstr);

794

734

}

795

735

}

796

736

}

824

764

while(true){

825

765

size_t out_size = strlen(out);

826

766

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

827

out_size - written));

767

out_size - written));

828

768

if(ret == -1){

829

769

int e = errno;

830

770

perror_plus("write");

850

790

}

851

791

852

792

if(debug){

853

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

793

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

854

794

}

855

795

856

796

if(quit_now){

858

798

goto mandos_end;

859

799

}

860

800

861

/* This casting via intptr_t is to eliminate warning about casting

862

an int to a pointer type. This is exactly how the GnuTLS Guile

863

function "set-session-transport-fd!" does it. */

864

gnutls_transport_set_ptr(session,

865

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

801

/* Spurious warning from -Wint-to-pointer-cast */

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

866

803

867

804

if(quit_now){

868

805

errno = EINTR;

879

816

880

817

if(ret != GNUTLS_E_SUCCESS){

881

818

if(debug){

882

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

819

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

883

820

gnutls_perror(ret);

884

821

}

885

822

errno = EPROTO;

889

826

/* Read OpenPGP packet that contains the wanted password */

890

827

891

828

if(debug){

892

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

893

" %s\n", ip);

829

fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",

830

ip);

894

831

}

895

832

896

833

while(true){

901

838

}

902

839

903

840

buffer_capacity = incbuffer(&buffer, buffer_length,

904

buffer_capacity);

841

buffer_capacity);

905

842

if(buffer_capacity == 0){

906

843

int e = errno;

907

844

perror_plus("incbuffer");

934

871

}

935

872

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

936

873

if(ret < 0){

937

fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "

938

"***\n");

874

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

939

875

gnutls_perror(ret);

940

876

errno = EPROTO;

941

877

goto mandos_end;

942

878

}

943

879

break;

944

880

default:

945

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

946

" encrypted session with Mandos server\n");

881

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

882

" encrypted session with Mandos server\n");

947

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

948

884

errno = EIO;

949

885

goto mandos_end;

954

890

}

955

891

956

892

if(debug){

957

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

893

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

958

894

}

959

895

960

896

if(quit_now){

972

908

973

909

if(buffer_length > 0){

974

910

ssize_t decrypted_buffer_size;

975

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

976

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

977

914

if(decrypted_buffer_size >= 0){

978

915

979

916

written = 0;

989

926

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

990

927

int e = errno;

991

928

if(debug){

992

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

993

strerror(errno));

929

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

930

strerror(errno));

994

931

}

995

932

errno = e;

996

933

goto mandos_end;

1040

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1041

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1042

979

flags,

1043

void* mc){

1044

if(r == NULL){

1045

return;

1046

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1047

982

1048

983

/* Called whenever a service has been resolved successfully or

1049

984

timed out */

1055

990

switch(event){

1056

991

default:

1057

992

case AVAHI_RESOLVER_FAILURE:

1058

fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "

1059

"'%s' of type '%s' in domain '%s': %s\n", name, type,

1060

domain,

1061

avahi_strerror(avahi_server_errno

1062

(((mandos_context*)mc)->server)));

993

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

994

" of type '%s' in domain '%s': %s\n", name, type, domain,

995

avahi_strerror(avahi_server_errno(mc.server)));

1063

996

break;

1064

997

1065

998

case AVAHI_RESOLVER_FOUND:

1067

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1068

1001

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

1069

1002

if(debug){

1070

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

1071

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

1072

host_name, ip, (intmax_t)interface, port);

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1073

1006

}

1074

int ret = start_mandos_communication(ip, (in_port_t)port,

1075

interface,

1076

avahi_proto_to_af(proto),

1077

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1078

1009

if(ret == 0){

1079

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1080

1011

} else {

1081

if(not add_server(ip, (in_port_t)port, interface,

1082

avahi_proto_to_af(proto),

1083

&((mandos_context*)mc)->current_server)){

1084

fprintf_plus(stderr, "Failed to add server \"%s\" to server"

1085

" list\n", name);

1086

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1087

1014

}

1088

1015

}

1089

1016

}

1099

1026

const char *domain,

1100

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1101

1028

flags,

1102

void* mc){

1103

if(b == NULL){

1104

return;

1105

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1106

1031

1107

1032

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

1108

1033

is removed from the LAN */

1115

1040

default:

1116

1041

case AVAHI_BROWSER_FAILURE:

1117

1042

1118

fprintf_plus(stderr, "(Avahi browser) %s\n",

1119

avahi_strerror(avahi_server_errno

1120

(((mandos_context*)mc)->server)));

1121

avahi_simple_poll_quit(simple_poll);

1043

fprintf(stderr, "(Avahi browser) %s\n",

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1122

1046

return;

1123

1047

1124

1048

case AVAHI_BROWSER_NEW:

1127

1051

the callback function is called the Avahi server will free the

1128

1052

resolver for us. */

1129

1053

1130

if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,

1131

interface, protocol, name, type,

1132

domain, protocol, 0,

1133

resolve_callback, mc) == NULL)

1134

fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"

1135

" %s\n", name,

1136

avahi_strerror(avahi_server_errno

1137

(((mandos_context*)mc)->server)));

1054

if(avahi_s_service_resolver_new(mc.server, interface, protocol,

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",

1058

name, avahi_strerror(avahi_server_errno(mc.server)));

1138

1059

break;

1139

1060

1140

1061

case AVAHI_BROWSER_REMOVE:

1143

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1144

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1145

1066

if(debug){

1146

fprintf_plus(stderr, "No Mandos server found, still"

1147

" searching...\n");

1067

fprintf(stderr, "No Mandos server found, still searching...\n");

1148

1068

}

1149

1069

break;

1150

1070

}

1159

1079

signal_received = sig;

1160

1080

int old_errno = errno;

1161

1081

/* set main loop to exit */

1162

if(simple_poll != NULL){

1163

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1164

1084

}

1165

1085

errno = old_errno;

1166

1086

}

1167

1087

1168

bool get_flags(const char *ifname, struct ifreq *ifr){

1169

int ret;

1170

error_t ret_errno;

1171

1172

int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1173

if(s < 0){

1174

ret_errno = errno;

1175

perror_plus("socket");

1176

errno = ret_errno;

1177

return false;

1178

}

1179

strcpy(ifr->ifr_name, ifname);

1180

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1181

if(ret == -1){

1088

/*

1089

* This function determines if a directory entry in /sys/class/net

1090

* corresponds to an acceptable network device.

1091

* (This function is passed to scandir(3) as a filter function.)

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

if(if_entry->d_name[0] == '.'){

1097

return 0;

1098

}

1099

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1116

flagstring[(size_t)to_read] = '\0';

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

tmpmax = strtoimax(flagstring, &tmp, 0);

1141

if(errno != 0 or tmp == flagstring or (*tmp != '\0'

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1182

1144

if(debug){

1183

ret_errno = errno;

1184

perror_plus("ioctl SIOCGIFFLAGS");

1185

errno = ret_errno;

1145

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1146

flagstring, if_entry->d_name);

1186

1147

}

1187

return false;

1148

free(flagstring);

1149

return 0;

1188

1150

}

1189

return true;

1190

}

1191

1192

bool good_flags(const char *ifname, const struct ifreq *ifr){

1193

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1194

1153

/* Reject the loopback device */

1195

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1196

1155

if(debug){

1197

fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",

1198

ifname);

1156

fprintf(stderr, "Rejecting loopback interface \"%s\"\n",

1157

if_entry->d_name);

1199

1158

}

1200

return false;

1159

return 0;

1201

1160

}

1202

1161

/* Accept point-to-point devices only if connect_to is specified */

1203

if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){

1162

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1204

1163

if(debug){

1205

fprintf_plus(stderr, "Accepting point-to-point interface"

1206

" \"%s\"\n", ifname);

1164

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1165

if_entry->d_name);

1207

1166

}

1208

return true;

1167

return 1;

1209

1168

}

1210

1169

/* Otherwise, reject non-broadcast-capable devices */

1211

if(not (ifr->ifr_flags & IFF_BROADCAST)){

1170

if(not (flags & IFF_BROADCAST)){

1212

1171

if(debug){

1213

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1214

" \"%s\"\n", ifname);

1172

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1173

if_entry->d_name);

1215

1174

}

1216

return false;

1175

return 0;

1217

1176

}

1218

1177

/* Reject non-ARP interfaces (including dummy interfaces) */

1219

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1220

1179

if(debug){

1221

fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",

1222

ifname);

1180

fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",

1181

if_entry->d_name);

1223

1182

}

1224

return false;

1183

return 0;

1225

1184

}

1226

1227

1185

/* Accept this device */

1228

1186

if(debug){

1229

fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);

1230

}

1231

return true;

1232

}

1233

1234

/*

1235

* This function determines if a directory entry in /sys/class/net

1236

* corresponds to an acceptable network device.

1237

* (This function is passed to scandir(3) as a filter function.)

1238

*/

1239

int good_interface(const struct dirent *if_entry){

1240

if(if_entry->d_name[0] == '.'){

1241

return 0;

1242

}

1243

1244

struct ifreq ifr;

1245

if(not get_flags(if_entry->d_name, &ifr)){

1246

if(debug){

1247

fprintf_plus(stderr, "Failed to get flags for interface "

1248

"\"%s\"\n", if_entry->d_name);

1249

}

1250

return 0;

1251

}

1252

1253

if(not good_flags(if_entry->d_name, &ifr)){

1254

return 0;

1187

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1188

if_entry->d_name);

1255

1189

}

1256

1190

return 1;

1257

1191

}

1258

1192

1259

/*

1260

* This function determines if a network interface is up.

1261

*/

1262

bool interface_is_up(const char *interface){

1263

struct ifreq ifr;

1264

if(not get_flags(interface, &ifr)){

1265

if(debug){

1266

fprintf_plus(stderr, "Failed to get flags for interface "

1267

"\"%s\"\n", interface);

1268

}

1269

return false;

1270

}

1271

1272

return (bool)(ifr.ifr_flags & IFF_UP);

1273

}

1274

1275

/*

1276

* This function determines if a network interface is running

1277

*/

1278

bool interface_is_running(const char *interface){

1279

struct ifreq ifr;

1280

if(not get_flags(interface, &ifr)){

1281

if(debug){

1282

fprintf_plus(stderr, "Failed to get flags for interface "

1283

"\"%s\"\n", interface);

1284

}

1285

return false;

1286

}

1287

1288

return (bool)(ifr.ifr_flags & IFF_RUNNING);

1289

}

1290

1291

1193

int notdotentries(const struct dirent *direntry){

1292

1194

/* Skip "." and ".." */

1293

1195

if(direntry->d_name[0] == '.'

1299

1201

return 1;

1300

1202

}

1301

1203

1302

/* Is this directory entry a runnable program? */

1303

int runnable_hook(const struct dirent *direntry){

1304

int ret;

1305

size_t sret;

1306

struct stat st;

1307

1308

if((direntry->d_name)[0] == '\0'){

1309

/* Empty name? */

1310

return 0;

1311

}

1312

1313

sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

1314

"abcdefghijklmnopqrstuvwxyz"

1315

"0123456789"

1316

"_-");

1317

if((direntry->d_name)[sret] != '\0'){

1318

/* Contains non-allowed characters */

1319

if(debug){

1320

fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",

1321

direntry->d_name);

1322

}

1323

return 0;

1324

}

1325

1326

char *fullname = NULL;

1327

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1328

if(ret < 0){

1329

perror_plus("asprintf");

1330

return 0;

1331

}

1332

1333

ret = stat(fullname, &st);

1334

if(ret == -1){

1335

if(debug){

1336

perror_plus("Could not stat hook");

1337

}

1338

return 0;

1339

}

1340

if(not (S_ISREG(st.st_mode))){

1341

/* Not a regular file */

1342

if(debug){

1343

fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",

1344

direntry->d_name);

1345

}

1346

return 0;

1347

}

1348

if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){

1349

/* Not executable */

1350

if(debug){

1351

fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",

1352

direntry->d_name);

1353

}

1354

return 0;

1355

}

1356

if(debug){

1357

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1358

direntry->d_name);

1359

}

1360

return 1;

1361

}

1362

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1365

1205

int ret;

1366

1206

struct timespec now;

1367

1207

struct timespec waited_time;

1368

1208

intmax_t block_time;

1369

1209

1370

1210

while(true){

1371

if(mc->current_server == NULL){

1211

if(mc.current_server == NULL){

1372

1212

if (debug){

1373

fprintf_plus(stderr, "Wait until first server is found."

1374

" No timeout!\n");

1213

fprintf(stderr,

1214

"Wait until first server is found. No timeout!\n");

1375

1215

}

1376

1216

ret = avahi_simple_poll_iterate(s, -1);

1377

1217

} else {

1378

1218

if (debug){

1379

fprintf_plus(stderr, "Check current_server if we should run"

1380

" it, or wait\n");

1219

fprintf(stderr, "Check current_server if we should run it,"

1220

" or wait\n");

1381

1221

}

1382

1222

/* the current time */

1383

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1388

1228

/* Calculating in ms how long time between now and server

1389

1229

who we visted longest time ago. Now - last seen. */

1390

1230

waited_time.tv_sec = (now.tv_sec

1391

- mc->current_server->last_seen.tv_sec);

1231

- mc.current_server->last_seen.tv_sec);

1392

1232

waited_time.tv_nsec = (now.tv_nsec

1393

- mc->current_server->last_seen.tv_nsec);

1233

- mc.current_server->last_seen.tv_nsec);

1394

1234

/* total time is 10s/10,000ms.

1395

1235

Converting to s from ms by dividing by 1,000,

1396

1236

and ns to ms by dividing by 1,000,000. */

1399

1239

- ((intmax_t)waited_time.tv_nsec / 1000000));

1400

1240

1401

1241

if (debug){

1402

fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",

1403

block_time);

1242

fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);

1404

1243

}

1405

1244

1406

1245

if(block_time <= 0){

1407

ret = start_mandos_communication(mc->current_server->ip,

1408

mc->current_server->port,

1409

mc->current_server->if_index,

1410

mc->current_server->af, mc);

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1411

1250

if(ret == 0){

1412

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

1413

1252

return 0;

1414

1253

}

1415

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1416

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

1417

1256

if(ret == -1){

1418

1257

perror_plus("clock_gettime");

1419

1258

return -1;

1420

1259

}

1421

mc->current_server = mc->current_server->next;

1260

mc.current_server = mc.current_server->next;

1422

1261

block_time = 0; /* Call avahi to find new Mandos

1423

1262

servers, but don't block */

1424

1263

}

1426

1265

ret = avahi_simple_poll_iterate(s, (int)block_time);

1427

1266

}

1428

1267

if(ret != 0){

1429

if (ret > 0 or errno != EINTR){

1268

if (ret > 0 or errno != EINTR) {

1430

1269

return (ret != 1) ? ret : 0;

1431

1270

}

1432

1271

}

1433

1272

}

1434

1273

}

1435

1274

1436

/* Set effective uid to 0, return errno */

1437

error_t raise_privileges(void){

1438

error_t old_errno = errno;

1439

error_t ret_errno = 0;

1440

if(seteuid(0) == -1){

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1443

}

1444

errno = old_errno;

1445

return ret_errno;

1446

}

1447

1448

/* Set effective and real user ID to 0. Return errno. */

1449

error_t raise_privileges_permanently(void){

1450

error_t old_errno = errno;

1451

error_t ret_errno = raise_privileges();

1452

if(ret_errno != 0){

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

if(setuid(0) == -1){

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1459

}

1460

errno = old_errno;

1461

return ret_errno;

1462

}

1463

1464

/* Set effective user ID to unprivileged saved user ID */

1465

error_t lower_privileges(void){

1466

error_t old_errno = errno;

1467

error_t ret_errno = 0;

1468

if(seteuid(uid) == -1){

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1471

}

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

1476

/* Lower privileges permanently */

1477

error_t lower_privileges_permanently(void){

1478

error_t old_errno = errno;

1479

error_t ret_errno = 0;

1480

if(setuid(uid) == -1){

1481

ret_errno = errno;

1482

perror_plus("setuid");

1483

}

1484

errno = old_errno;

1485

return ret_errno;

1486

}

1487

1488

bool run_network_hooks(const char *mode, const char *interface,

1489

const float delay){

1490

struct dirent **direntries;

1491

struct dirent *direntry;

1492

int ret;

1493

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1494

alphasort);

1495

if(numhooks == -1){

1496

if(errno == ENOENT){

1497

if(debug){

1498

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

1503

}

1504

} else {

1505

int devnull = open("/dev/null", O_RDONLY);

1506

for(int i = 0; i < numhooks; i++){

1507

direntry = direntries[i];

1508

char *fullname = NULL;

1509

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1510

if(ret < 0){

1511

perror_plus("asprintf");

1512

continue;

1513

}

1514

if(debug){

1515

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1516

direntry->d_name);

1517

}

1518

pid_t hook_pid = fork();

1519

if(hook_pid == 0){

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1535

dup2(devnull, STDIN_FILENO);

1536

close(devnull);

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1538

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1539

if(ret == -1){

1540

perror_plus("setenv");

1541

_exit(EX_OSERR);

1542

}

1543

ret = setenv("DEVICE", interface, 1);

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

ret = setenv("MODE", mode, 1);

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

char *delaystring;

1559

ret = asprintf(&delaystring, "%f", delay);

1560

if(ret == -1){

1561

perror_plus("asprintf");

1562

_exit(EX_OSERR);

1563

}

1564

ret = setenv("DELAY", delaystring, 1);

1565

if(ret == -1){

1566

free(delaystring);

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1570

free(delaystring);

1571

if(connect_to != NULL){

1572

ret = setenv("CONNECT", connect_to, 1);

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

1582

} else {

1583

int status;

1584

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1585

perror_plus("waitpid");

1586

free(fullname);

1587

continue;

1588

}

1589

if(WIFEXITED(status)){

1590

if(WEXITSTATUS(status) != 0){

1591

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1592

" with status %d\n", direntry->d_name,

1593

WEXITSTATUS(status));

1594

free(fullname);

1595

continue;

1596

}

1597

} else if(WIFSIGNALED(status)){

1598

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1599

" signal %d\n", direntry->d_name,

1600

WTERMSIG(status));

1601

free(fullname);

1602

continue;

1603

} else {

1604

fprintf_plus(stderr, "Warning: network hook \"%s\""

1605

" crashed\n", direntry->d_name);

1606

free(fullname);

1607

continue;

1608

}

1609

}

1610

free(fullname);

1611

if(debug){

1612

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1613

direntry->d_name);

1614

}

1615

}

1616

close(devnull);

1617

}

1618

return true;

1619

}

1620

1621

error_t bring_up_interface(const char *const interface,

1622

const float delay){

1623

int sd = -1;

1624

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1627

struct ifreq network;

1628

unsigned int if_index = if_nametoindex(interface);

1629

if(if_index == 0){

1630

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

1631

errno = old_errno;

1632

return ENXIO;

1633

}

1634

1635

if(quit_now){

1636

errno = old_errno;

1637

return EINTR;

1638

}

1639

1640

if(not interface_is_up(interface)){

1641

if(not get_flags(interface, &network) and debug){

1642

ret_errno = errno;

1643

fprintf_plus(stderr, "Failed to get flags for interface "

1644

"\"%s\"\n", interface);

1645

return ret_errno;

1646

}

1647

network.ifr_flags |= IFF_UP;

1648

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1651

ret_errno = errno;

1652

perror_plus("socket");

1653

errno = old_errno;

1654

return ret_errno;

1655

}

1656

1657

if(quit_now){

1658

close(sd);

1659

errno = old_errno;

1660

return EINTR;

1661

}

1662

1663

if(debug){

1664

fprintf_plus(stderr, "Bringing up interface \"%s\"\n",

1665

interface);

1666

}

1667

1668

/* Raise priviliges */

1669

raise_privileges();

1670

1671

#ifdef __linux__

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

messages about the network interface to mess up the prompt */

1674

int ret_linux = klogctl(8, NULL, 5);

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

1679

}

1680

#endif /* __linux__ */

1681

ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

1682

ret_errno = errno;

1683

#ifdef __linux__

1684

if(restore_loglevel){

1685

ret_linux = klogctl(7, NULL, 0);

1686

if(ret_linux == -1){

1687

perror_plus("klogctl");

1688

}

1689

}

1690

#endif /* __linux__ */

1691

1692

/* Lower privileges */

1693

lower_privileges();

1694

1695

/* Close the socket */

1696

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

1697

if(ret == -1){

1698

perror_plus("close");

1699

}

1700

1701

if(ret_setflags == -1){

1702

errno = ret_errno;

1703

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

} else if(debug){

1708

fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",

1709

interface);

1710

}

1711

1712

/* Sleep checking until interface is running.

1713

Check every 0.25s, up to total time of delay */

1714

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

1715

if(interface_is_running(interface)){

1716

break;

1717

}

1718

struct timespec sleeptime = { .tv_nsec = 250000000 };

1719

ret = nanosleep(&sleeptime, NULL);

1720

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

1721

perror_plus("nanosleep");

1722

}

1723

}

1724

1725

errno = old_errno;

1726

return 0;

1727

}

1728

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1734

struct ifreq network;

1735

unsigned int if_index = if_nametoindex(interface);

1736

if(if_index == 0){

1737

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

1738

errno = old_errno;

1739

return ENXIO;

1740

}

1741

if(interface_is_up(interface)){

1742

if(not get_flags(interface, &network) and debug){

1743

ret_errno = errno;

1744

fprintf_plus(stderr, "Failed to get flags for interface "

1745

"\"%s\"\n", interface);

1746

return ret_errno;

1747

}

1748

network.ifr_flags &= ~(short)IFF_UP; /* clear flag */

1749

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1752

ret_errno = errno;

1753

perror_plus("socket");

1754

errno = old_errno;

1755

return ret_errno;

1756

}

1757

1758

if(debug){

1759

fprintf_plus(stderr, "Taking down interface \"%s\"\n",

1760

interface);

1761

}

1762

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

1771

1772

/* Close the socket */

1773

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

1774

if(ret == -1){

1775

perror_plus("close");

1776

}

1777

1778

if(ret_setflags == -1){

1779

errno = ret_errno;

1780

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

errno = old_errno;

1782

return ret_errno;

1783

}

1784

} else if(debug){

1785

fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",

1786

interface);

1787

}

1788

1789

errno = old_errno;

1790

return 0;

1791

}

1792

1793

1275

int main(int argc, char *argv[]){

1794

mandos_context mc = { .server = NULL, .dh_bits = 1024,

1795

.priority = "SECURE256:!CTYPE-X.509:"

1796

"+CTYPE-OPENPGP", .current_server = NULL,

1797

.interfaces = NULL, .interfaces_size = 0 };

1798

1276

AvahiSServiceBrowser *sb = NULL;

1799

error_t ret_errno;

1277

int error;

1800

1278

int ret;

1801

1279

intmax_t tmpmax;

1802

1280

char *tmp;

1803

1281

int exitcode = EXIT_SUCCESS;

1804

char *interfaces_to_take_down = NULL;

1805

size_t interfaces_to_take_down_size = 0;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1806

1288

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

1807

1289

bool tempdir_created = false;

1808

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1809

1291

const char *seckey = PATHDIR "/" SECKEY;

1810

1292

const char *pubkey = PATHDIR "/" PUBKEY;

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1813

1293

1814

1294

bool gnutls_initialized = false;

1815

1295

bool gpgme_initialized = false;

1877

1357

.group = 2 },

1878

1358

{ .name = "retry", .key = 132,

1879

1359

.arg = "SECONDS",

1880

.doc = "Retry interval used when denied by the Mandos server",

1881

.group = 2 },

1882

{ .name = "network-hook-dir", .key = 133,

1883

.arg = "DIR",

1884

.doc = "Directory where network hooks are located",

1360

.doc = "Retry interval used when denied by the mandos server",

1885

1361

.group = 2 },

1886

1362

/*

1887

1363

* These reproduce what we would get without ARGP_NO_HELP

1906

1382

connect_to = arg;

1907

1383

break;

1908

1384

case 'i': /* --interface */

1909

ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,

1910

arg, (int)',');

1911

if(ret_errno != 0){

1912

argp_error(state, "%s", strerror(ret_errno));

1913

}

1385

interface = arg;

1914

1386

break;

1915

1387

case 's': /* --seckey */

1916

1388

seckey = arg;

1945

1417

argp_error(state, "Bad retry interval");

1946

1418

}

1947

1419

break;

1948

case 133: /* --network-hook-dir */

1949

hookdir = arg;

1950

break;

1951

1420

/*

1952

1421

* These reproduce what we would get without ARGP_NO_HELP

1953

1422

*/

1959

1428

argp_state_help(state, state->out_stream,

1960

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1961

1430

case 'V': /* --version */

1962

fprintf_plus(state->out_stream, "%s\n", argp_program_version);

1431

fprintf(state->out_stream, "%s\n", argp_program_version);

1963

1432

exit(argp_err_exit_status);

1964

1433

break;

1965

1434

default:

1992

1461

{

1993

1462

/* Work around Debian bug #633582:

1994

1463

<http://bugs.debian.org/633582> */

1464

struct stat st;

1995

1465

1996

1466

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

1998

struct stat st;

1999

2000

if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){

2001

int seckey_fd = open(seckey, O_RDONLY);

2002

if(seckey_fd == -1){

2003

perror_plus("open");

2004

} else {

2005

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

2006

if(ret == -1){

2007

perror_plus("fstat");

2008

} else {

2009

if(S_ISREG(st.st_mode)

2010

and st.st_uid == 0 and st.st_gid == 0){

2011

ret = fchown(seckey_fd, uid, gid);

2012

if(ret == -1){

2013

perror_plus("fchown");

2014

}

2015

}

2016

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2018

}

2019

}

2020

2021

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

2022

int pubkey_fd = open(pubkey, O_RDONLY);

2023

if(pubkey_fd == -1){

2024

perror_plus("open");

2025

} else {

2026

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

2027

if(ret == -1){

2028

perror_plus("fstat");

2029

} else {

2030

if(S_ISREG(st.st_mode)

2031

and st.st_uid == 0 and st.st_gid == 0){

2032

ret = fchown(pubkey_fd, uid, gid);

2033

if(ret == -1){

2034

perror_plus("fchown");

2035

}

2036

}

2037

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

2042

/* Lower privileges */

2043

lower_privileges();

2044

}

2045

}

2046

2047

/* Remove invalid interface names (except "none") */

2048

{

2049

char *interface = NULL;

2050

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2051

interface))){

2052

if(strcmp(interface, "none") != 0

2053

and if_nametoindex(interface) == 0){

2054

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

2055

fprintf_plus(stderr, "Not using nonexisting interface"

2056

" \"%s\"\n", interface);

2057

}

2058

argz_delete(&mc.interfaces, &mc.interfaces_size, interface);

2059

interface = NULL;

2060

}

2061

}

2062

}

2063

2064

/* Run network hooks */

2065

{

2066

if(mc.interfaces != NULL){

2067

interfaces_hooks = malloc(mc.interfaces_size);

2068

if(interfaces_hooks == NULL){

2069

perror_plus("malloc");

2070

goto end;

2071

}

2072

memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

2076

}

2077

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2078

interfaces_hooks : "", delay)){

2079

goto end;

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

2080

1518

}

2081

1519

}

2082

1520

2083

1521

if(not debug){

2084

1522

avahi_set_log_function(empty_log);

2085

1523

}

1524

1525

if(interface[0] == '\0'){

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

interface = strdup(direntries[0]->d_name);

1532

if(debug){

1533

fprintf(stderr, "Using interface \"%s\"\n", interface);

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

fprintf(stderr, "Could not find a network interface\n");

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

2086

1549

2087

1550

/* Initialize Avahi early so avahi_simple_poll_quit() can be called

2088

1551

from the signal handler */

2089

1552

/* Initialize the pseudo-RNG for Avahi */

2090

1553

srand((unsigned int) time(NULL));

2091

simple_poll = avahi_simple_poll_new();

2092

if(simple_poll == NULL){

2093

fprintf_plus(stderr,

2094

"Avahi: Failed to create simple poll object.\n");

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

2095

1557

exitcode = EX_UNAVAILABLE;

2096

1558

goto end;

2097

1559

}

2159

1621

}

2160

1622

}

2161

1623

2162

/* If no interfaces were specified, make a list */

2163

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2165

/* Look for any good interfaces */

2166

ret = scandir(sys_class_net, &direntries, good_interface,

2167

alphasort);

2168

if(ret >= 1){

2169

/* Add all found interfaces to interfaces list */

2170

for(int i = 0; i < ret; ++i){

2171

ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,

2172

direntries[i]->d_name);

2173

if(ret_errno != 0){

2174

perror_plus("argz_add");

2175

continue;

2176

}

2177

if(debug){

2178

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2179

direntries[i]->d_name);

2180

}

2181

}

2182

free(direntries);

2183

} else {

2184

free(direntries);

2185

fprintf_plus(stderr, "Could not find a network interface\n");

2186

exitcode = EXIT_FAILURE;

2187

goto end;

2188

}

2189

}

2190

2191

/* Bring up interfaces which are down, and remove any "none"s */

2192

{

2193

char *interface = NULL;

2194

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2195

interface))){

2196

/* If interface name is "none", stop bringing up interfaces.

2197

Also remove all instances of "none" from the list */

2198

if(strcmp(interface, "none") == 0){

2199

argz_delete(&mc.interfaces, &mc.interfaces_size,

2200

interface);

2201

interface = NULL;

2202

while((interface = argz_next(mc.interfaces,

2203

mc.interfaces_size, interface))){

2204

if(strcmp(interface, "none") == 0){

2205

argz_delete(&mc.interfaces, &mc.interfaces_size,

2206

interface);

2207

interface = NULL;

1624

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

1625

if(strcmp(interface, "none") != 0){

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

messages about the network interface to mess up the prompt */

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

if((network.ifr_flags & IFF_UP) == 0){

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

2208

1709

}

2209

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

Check every 0.25s, up to total time of delay */

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

2210

1728

break;

2211

1729

}

2212

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2214

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2217

perror_plus("Failed to bring up interface");

2218

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2222

}

2223

}

2224

}

2225

if(debug and (interfaces_to_take_down == NULL)){

2226

fprintf_plus(stderr, "No interfaces were brought up\n");

2227

}

2228

}

2229

2230

/* If we only got one interface, explicitly use only that one */

2231

if(argz_count(mc.interfaces, mc.interfaces_size) == 1){

2232

if(debug){

2233

fprintf_plus(stderr, "Using only interface \"%s\"\n",

2234

mc.interfaces);

2235

}

2236

if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

/* We won't need the socket anymore */

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

2237

1767

}

2238

1768

2239

1769

if(quit_now){

2240

1770

goto end;

2241

1771

}

2242

1772

2243

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

1773

ret = init_gnutls_global(pubkey, seckey);

2244

1774

if(ret == -1){

2245

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

1775

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

2246

1776

exitcode = EX_UNAVAILABLE;

2247

1777

goto end;

2248

1778

} else {

2263

1793

goto end;

2264

1794

}

2265

1795

2266

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

2267

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

1796

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

1797

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

2268

1798

exitcode = EX_UNAVAILABLE;

2269

1799

goto end;

2270

1800

} else {

2279

1809

/* Connect directly, do not use Zeroconf */

2280

1810

/* (Mainly meant for debugging) */

2281

1811

char *address = strrchr(connect_to, ':');

2282

2283

1812

if(address == NULL){

2284

fprintf_plus(stderr, "No colon in address\n");

1813

fprintf(stderr, "No colon in address\n");

2285

1814

exitcode = EX_USAGE;

2286

1815

goto end;

2287

1816

}

2290

1819

goto end;

2291

1820

}

2292

1821

2293

in_port_t port;

1822

uint16_t port;

2294

1823

errno = 0;

2295

1824

tmpmax = strtoimax(address+1, &tmp, 10);

2296

1825

if(errno != 0 or tmp == address+1 or *tmp != '\0'

2297

or tmpmax != (in_port_t)tmpmax){

2298

fprintf_plus(stderr, "Bad port number\n");

1826

or tmpmax != (uint16_t)tmpmax){

1827

fprintf(stderr, "Bad port number\n");

2299

1828

exitcode = EX_USAGE;

2300

1829

goto end;

2301

1830

}

2302

1831

2303

1832

if(quit_now){

2304

1833

goto end;

2305

1834

}

2306

1835

2307

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

2308

1837

*address = '\0';

2309

1838

/* Colon in address indicates IPv6 */

2310

1839

int af;

2326

1855

}

2327

1856

2328

1857

while(not quit_now){

2329

ret = start_mandos_communication(address, port, if_index, af,

2330

&mc);

1858

ret = start_mandos_communication(address, port, if_index, af);

2331

1859

if(quit_now or ret == 0){

2332

1860

break;

2333

1861

}

2334

1862

if(debug){

2335

fprintf_plus(stderr, "Retrying in %d seconds\n",

2336

(int)retry_interval);

1863

fprintf(stderr, "Retrying in %d seconds\n",

1864

(int)retry_interval);

2337

1865

}

2338

sleep((unsigned int)retry_interval);

1866

sleep((int)retry_interval);

2339

1867

}

2340

1868

2341

1869

if (not quit_now){

2342

1870

exitcode = EXIT_SUCCESS;

2343

1871

}

2344

1872

2345

1873

goto end;

2346

1874

}

2347

1875

2359

1887

config.publish_domain = 0;

2360

1888

2361

1889

/* Allocate a new server */

2362

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2363

&config, NULL, NULL, &ret_errno);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2364

1893

2365

1894

/* Free the Avahi configuration data */

2366

1895

avahi_server_config_free(&config);

2368

1897

2369

1898

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

2370

1899

if(mc.server == NULL){

2371

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

2372

avahi_strerror(ret_errno));

1900

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

1901

avahi_strerror(error));

2373

1902

exitcode = EX_UNAVAILABLE;

2374

1903

goto end;

2375

1904

}

2381

1910

/* Create the Avahi service browser */

2382

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

2383

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2384

NULL, 0, browse_callback,

2385

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

2386

1914

if(sb == NULL){

2387

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

2388

avahi_strerror(avahi_server_errno(mc.server)));

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2389

1917

exitcode = EX_UNAVAILABLE;

2390

1918

goto end;

2391

1919

}

2397

1925

/* Run the main loop */

2398

1926

2399

1927

if(debug){

2400

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

1928

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

2401

1929

}

2402

1930

2403

ret = avahi_loop_with_timeout(simple_poll,

2404

(int)(retry_interval * 1000), &mc);

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2405

1933

if(debug){

2406

fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",

2407

(ret == 0) ? "successfully" : "with error");

1934

fprintf(stderr, "avahi_loop_with_timeout exited %s\n",

1935

(ret == 0) ? "successfully" : "with error");

2408

1936

}

2409

1937

2410

1938

end:

2411

1939

2412

1940

if(debug){

2413

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

1941

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

2414

1942

}

2415

1943

2416

1944

/* Cleanup things */

2417

free(mc.interfaces);

2418

2419

1945

if(sb != NULL)

2420

1946

avahi_s_service_browser_free(sb);

2421

1947

2422

1948

if(mc.server != NULL)

2423

1949

avahi_server_free(mc.server);

2424

1950

2425

if(simple_poll != NULL)

2426

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2427

1953

2428

1954

if(gnutls_initialized){

2429

1955

gnutls_certificate_free_credentials(mc.cred);

2434

1960

if(gpgme_initialized){

2435

1961

gpgme_release(mc.ctx);

2436

1962

}

2437

1963

2438

1964

/* Cleans up the circular linked list of Mandos servers the client

2439

1965

has seen */

2440

1966

if(mc.current_server != NULL){

2446

1972

}

2447

1973

}

2448

1974

2449

/* Re-raise priviliges */

2450

{

2451

raise_privileges();

2452

2453

/* Run network hooks */

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2456

2457

/* Take down the network interfaces which were brought up */

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

network.ifr_flags &= ~(short)IFF_UP; /* clear flag */

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2467

1992

}

2468

1993

}

2469

if(debug and (interfaces_to_take_down == NULL)){

2470

fprintf_plus(stderr, "No interfaces needed to be taken"

2471

" down\n");

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2472

2003

}

2473

2004

}

2474

2475

lower_privileges_permanently();

2476

2005

}

2477

2006

2478

free(interfaces_to_take_down);

2479

free(interfaces_hooks);

2480

2481

2007

/* Removes the GPGME temp directory and all files inside */

2482

2008

if(tempdir_created){

2483

2009

struct dirent **direntries = NULL;

2496

2022

}

2497

2023

ret = remove(fullname);

2498

2024

if(ret == -1){

2499

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

2500

strerror(errno));

2025

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

2026

strerror(errno));

2501

2027

}

2502

2028

free(fullname);

2503

2029

}