/mandos/trunk : revision 505.2.4

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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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#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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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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const char *argp_program_bug_address = "<mandos@recompile.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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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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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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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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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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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;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ", program_invocation_short_name));

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

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}

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/*

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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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if(buffer == NULL){

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}

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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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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){

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perror_plus("strdup");

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return false;

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return -1;

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}

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/* Special case of first server */

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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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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 */

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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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if(ret == -1){

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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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}

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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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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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*/

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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if(rc != GPG_ERR_NO_ERROR){

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fprintf_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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}

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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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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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return false;

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}

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while(engine_info != NULL){

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engine_info = engine_info->next;

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}

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if(engine_info == NULL){

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

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tempdir);

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

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return false;

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}

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/* Create new GPGME "context" */

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

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

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if(rc != GPG_ERR_NO_ERROR){

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

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

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gpgme_strerror(rc));

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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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321

}

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*/

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static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

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size_t crypto_size,

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char **plaintext,

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mandos_context *mc){

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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;

353

341

ssize_t plaintext_length = 0;

354

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if(debug){

356

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

344

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

357

345

}

358

346

359

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

360

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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

361

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0);

362

350

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));

351

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

352

gpgme_strsource(rc), gpgme_strerror(rc));

365

353

return -1;

366

354

}

367

355

368

356

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

369

357

rc = gpgme_data_new(&dh_plain);

370

358

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));

359

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

360

gpgme_strsource(rc), gpgme_strerror(rc));

374

361

gpgme_data_release(dh_crypto);

375

362

return -1;

376

363

}

377

364

378

365

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

379

366

data buffer */

380

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

367

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

381

368

if(rc != GPG_ERR_NO_ERROR){

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

384

371

plaintext_length = -1;

385

372

if(debug){

386

373

gpgme_decrypt_result_t result;

387

result = gpgme_op_decrypt_result(mc->ctx);

374

result = gpgme_op_decrypt_result(mc.ctx);

388

375

if(result == NULL){

389

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

376

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

390

377

} 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);

378

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

379

result->unsupported_algorithm);

380

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

381

result->wrong_key_usage);

395

382

if(result->file_name != NULL){

396

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

383

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

397

384

}

398

385

gpgme_recipient_t recipient;

399

386

recipient = result->recipients;

400

387

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");

388

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

389

gpgme_pubkey_algo_name(recipient->pubkey_algo));

390

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

391

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

392

recipient->status == GPG_ERR_NO_SECKEY

393

? "No" : "Yes");

408

394

recipient = recipient->next;

409

395

}

410

396

}

413

399

}

414

400

415

401

if(debug){

416

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

402

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

417

403

}

418

404

419

405

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

426

412

*plaintext = NULL;

427

413

while(true){

428

414

plaintext_capacity = incbuffer(plaintext,

429

(size_t)plaintext_length,

430

plaintext_capacity);

415

(size_t)plaintext_length,

416

plaintext_capacity);

431

417

if(plaintext_capacity == 0){

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

418

perror_plus("incbuffer");

419

plaintext_length = -1;

420

goto decrypt_end;

435

421

}

436

422

437

423

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

450

436

}

451

437

452

438

if(debug){

453

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

439

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

454

440

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

455

441

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

456

442

}

468

454

}

469

455

470

456

static const char * safer_gnutls_strerror(int value){

471

const char *ret = gnutls_strerror(value);

457

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

458

-Wunreachable-code */

472

459

if(ret == NULL)

473

460

ret = "(unknown)";

474

461

return ret;

477

464

/* GnuTLS log function callback */

478

465

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

479

466

const char* string){

480

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

467

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

481

468

}

482

469

483

470

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename,

485

mandos_context *mc){

471

const char *seckeyfilename){

486

472

int ret;

487

473

488

474

if(debug){

489

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

475

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

490

476

}

491

477

492

478

ret = gnutls_global_init();

493

479

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

480

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

481

safer_gnutls_strerror(ret));

496

482

return -1;

497

483

}

498

484

505

491

}

506

492

507

493

/* OpenPGP credentials */

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

494

ret = gnutls_certificate_allocate_credentials(&mc.cred);

509

495

if(ret != GNUTLS_E_SUCCESS){

510

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

511

safer_gnutls_strerror(ret));

496

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

497

safer_gnutls_strerror(ret));

512

498

gnutls_global_deinit();

513

499

return -1;

514

500

}

515

501

516

502

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);

503

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

504

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

505

seckeyfilename);

521

506

}

522

507

523

508

ret = gnutls_certificate_set_openpgp_key_file

524

(mc->cred, pubkeyfilename, seckeyfilename,

509

(mc.cred, pubkeyfilename, seckeyfilename,

525

510

GNUTLS_OPENPGP_FMT_BASE64);

526

511

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));

512

fprintf(stderr,

513

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

514

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

515

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

516

safer_gnutls_strerror(ret));

532

517

goto globalfail;

533

518

}

534

519

535

520

/* GnuTLS server initialization */

536

ret = gnutls_dh_params_init(&mc->dh_params);

521

ret = gnutls_dh_params_init(&mc.dh_params);

537

522

if(ret != GNUTLS_E_SUCCESS){

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

523

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

524

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

541

525

goto globalfail;

542

526

}

543

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

527

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

544

528

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

529

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

530

safer_gnutls_strerror(ret));

547

531

goto globalfail;

548

532

}

549

533

550

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

534

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

551

535

552

536

return 0;

553

537

554

538

globalfail:

555

539

556

gnutls_certificate_free_credentials(mc->cred);

540

gnutls_certificate_free_credentials(mc.cred);

557

541

gnutls_global_deinit();

558

gnutls_dh_params_deinit(mc->dh_params);

542

gnutls_dh_params_deinit(mc.dh_params);

559

543

return -1;

560

544

}

561

545

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

546

static int init_gnutls_session(gnutls_session_t *session){

564

547

int ret;

565

548

/* GnuTLS session creation */

566

549

do {

570

553

}

571

554

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

572

555

if(ret != GNUTLS_E_SUCCESS){

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

556

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

557

safer_gnutls_strerror(ret));

576

558

}

577

559

578

560

{

579

561

const char *err;

580

562

do {

581

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

563

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

582

564

if(quit_now){

583

565

gnutls_deinit(*session);

584

566

return -1;

585

567

}

586

568

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

587

569

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));

570

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

571

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

572

safer_gnutls_strerror(ret));

591

573

gnutls_deinit(*session);

592

574

return -1;

593

575

}

595

577

596

578

do {

597

579

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

598

mc->cred);

580

mc.cred);

599

581

if(quit_now){

600

582

gnutls_deinit(*session);

601

583

return -1;

602

584

}

603

585

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

604

586

if(ret != GNUTLS_E_SUCCESS){

605

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

606

safer_gnutls_strerror(ret));

587

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

588

safer_gnutls_strerror(ret));

607

589

gnutls_deinit(*session);

608

590

return -1;

609

591

}

611

593

/* ignore client certificate if any. */

612

594

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

595

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

596

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

615

597

616

598

return 0;

617

599

}

621

603

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

622

604

623

605

/* Called when a Mandos server is found */

624

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

606

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

625

607

AvahiIfIndex if_index,

626

int af, mandos_context *mc){

608

int af){

627

609

int ret, tcp_sd = -1;

628

610

ssize_t sret;

629

611

union {

654

636

pf = PF_INET;

655

637

break;

656

638

default:

657

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

639

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

658

640

errno = EINVAL;

659

641

return -1;

660

642

}

661

643

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);

644

ret = init_gnutls_session(&session);

695

645

if(ret != 0){

696

646

return -1;

697

647

}

698

648

699

649

if(debug){

700

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

701

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

650

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

651

"\n", ip, port);

702

652

}

703

653

704

654

tcp_sd = socket(pf, SOCK_STREAM, 0);

730

680

}

731

681

if(ret == 0){

732

682

int e = errno;

733

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

683

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

734

684

errno = e;

735

685

goto mandos_end;

736

686

}

737

687

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

688

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

689

-Wconversion and

690

-Wunreachable-code */

691

743

692

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

693

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

694

-Wunreachable-code*/

748

695

if(if_index == AVAHI_IF_UNSPEC){

749

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

750

" incomplete without a network interface\n");

696

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

697

" without a network interface\n");

751

698

errno = EINVAL;

752

699

goto mandos_end;

753

700

}

755

702

to.in6.sin6_scope_id = (uint32_t)if_index;

756

703

}

757

704

} else {

758

to.in.sin_port = htons(port);

705

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

706

-Wconversion and

707

-Wunreachable-code */

759

708

}

760

709

761

710

if(quit_now){

769

718

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

770

719

perror_plus("if_indextoname");

771

720

} else {

772

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

773

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

721

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

722

ip, interface, port);

774

723

}

775

724

} else {

776

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

777

ip, (uintmax_t)port);

725

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

726

port);

778

727

}

779

728

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

780

729

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

790

739

perror_plus("inet_ntop");

791

740

} else {

792

741

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

793

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

742

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

794

743

}

795

744

}

796

745

}

824

773

while(true){

825

774

size_t out_size = strlen(out);

826

775

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

827

out_size - written));

776

out_size - written));

828

777

if(ret == -1){

829

778

int e = errno;

830

779

perror_plus("write");

850

799

}

851

800

852

801

if(debug){

853

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

802

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

854

803

}

855

804

856

805

if(quit_now){

858

807

goto mandos_end;

859

808

}

860

809

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);

810

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

811

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

866

812

867

813

if(quit_now){

868

814

errno = EINTR;

879

825

880

826

if(ret != GNUTLS_E_SUCCESS){

881

827

if(debug){

882

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

828

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

883

829

gnutls_perror(ret);

884

830

}

885

831

errno = EPROTO;

889

835

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

890

836

891

837

if(debug){

892

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

893

" %s\n", ip);

838

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

839

ip);

894

840

}

895

841

896

842

while(true){

901

847

}

902

848

903

849

buffer_capacity = incbuffer(&buffer, buffer_length,

904

buffer_capacity);

850

buffer_capacity);

905

851

if(buffer_capacity == 0){

906

852

int e = errno;

907

853

perror_plus("incbuffer");

934

880

}

935

881

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

936

882

if(ret < 0){

937

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

938

"***\n");

883

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

939

884

gnutls_perror(ret);

940

885

errno = EPROTO;

941

886

goto mandos_end;

942

887

}

943

888

break;

944

889

default:

945

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

946

" encrypted session with Mandos server\n");

890

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

891

" encrypted session with Mandos server\n");

947

892

gnutls_bye(session, GNUTLS_SHUT_RDWR);

948

893

errno = EIO;

949

894

goto mandos_end;

954

899

}

955

900

956

901

if(debug){

957

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

902

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

958

903

}

959

904

960

905

if(quit_now){

972

917

973

918

if(buffer_length > 0){

974

919

ssize_t decrypted_buffer_size;

975

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

976

&decrypted_buffer, mc);

920

decrypted_buffer_size = pgp_packet_decrypt(buffer,

921

buffer_length,

922

&decrypted_buffer);

977

923

if(decrypted_buffer_size >= 0){

978

924

979

925

written = 0;

989

935

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

990

936

int e = errno;

991

937

if(debug){

992

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

993

strerror(errno));

938

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

939

strerror(errno));

994

940

}

995

941

errno = e;

996

942

goto mandos_end;

1040

986

AVAHI_GCC_UNUSED AvahiStringList *txt,

1041

987

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1042

988

flags,

1043

void* mc){

1044

if(r == NULL){

1045

return;

1046

}

989

AVAHI_GCC_UNUSED void* userdata){

990

assert(r);

1047

991

1048

992

/* Called whenever a service has been resolved successfully or

1049

993

timed out */

1055

999

switch(event){

1056

1000

default:

1057

1001

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)));

1002

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

1003

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

1004

avahi_strerror(avahi_server_errno(mc.server)));

1063

1005

break;

1064

1006

1065

1007

case AVAHI_RESOLVER_FOUND:

1067

1009

char ip[AVAHI_ADDRESS_STR_MAX];

1068

1010

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

1069

1011

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);

1012

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

1013

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

1014

ip, (intmax_t)interface, port);

1073

1015

}

1074

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

1075

interface,

1076

avahi_proto_to_af(proto),

1077

mc);

1016

int ret = start_mandos_communication(ip, port, interface,

1017

avahi_proto_to_af(proto));

1078

1018

if(ret == 0){

1079

avahi_simple_poll_quit(simple_poll);

1019

avahi_simple_poll_quit(mc.simple_poll);

1080

1020

} 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

}

1021

ret = add_server(ip, port, interface,

1022

avahi_proto_to_af(proto));

1087

1023

}

1088

1024

}

1089

1025

}

1099

1035

const char *domain,

1100

1036

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1101

1037

flags,

1102

void* mc){

1103

if(b == NULL){

1104

return;

1105

}

1038

AVAHI_GCC_UNUSED void* userdata){

1039

assert(b);

1106

1040

1107

1041

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

1108

1042

is removed from the LAN */

1115

1049

default:

1116

1050

case AVAHI_BROWSER_FAILURE:

1117

1051

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);

1052

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

1053

avahi_strerror(avahi_server_errno(mc.server)));

1054

avahi_simple_poll_quit(mc.simple_poll);

1122

1055

return;

1123

1056

1124

1057

case AVAHI_BROWSER_NEW:

1127

1060

the callback function is called the Avahi server will free the

1128

1061

resolver for us. */

1129

1062

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)));

1063

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

1064

name, type, domain, protocol, 0,

1065

resolve_callback, NULL) == NULL)

1066

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

1067

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

1138

1068

break;

1139

1069

1140

1070

case AVAHI_BROWSER_REMOVE:

1143

1073

case AVAHI_BROWSER_ALL_FOR_NOW:

1144

1074

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1145

1075

if(debug){

1146

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

1147

" searching...\n");

1076

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

1148

1077

}

1149

1078

break;

1150

1079

}

1159

1088

signal_received = sig;

1160

1089

int old_errno = errno;

1161

1090

/* set main loop to exit */

1162

if(simple_poll != NULL){

1163

avahi_simple_poll_quit(simple_poll);

1091

if(mc.simple_poll != NULL){

1092

avahi_simple_poll_quit(mc.simple_poll);

1164

1093

}

1165

1094

errno = old_errno;

1166

1095

}

1167

1096

1168

1097

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

1169

1098

int ret;

1170

error_t ret_errno;

1171

1099

1172

1100

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

1173

1101

if(s < 0){

1174

ret_errno = errno;

1175

1102

perror_plus("socket");

1176

errno = ret_errno;

1177

1103

return false;

1178

1104

}

1179

1105

strcpy(ifr->ifr_name, ifname);

1180

1106

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1181

1107

if(ret == -1){

1182

1108

if(debug){

1183

ret_errno = errno;

1184

1109

perror_plus("ioctl SIOCGIFFLAGS");

1185

errno = ret_errno;

1186

1110

}

1187

1111

return false;

1188

1112

}

1194

1118

/* Reject the loopback device */

1195

1119

if(ifr->ifr_flags & IFF_LOOPBACK){

1196

1120

if(debug){

1197

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

1198

ifname);

1121

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

1122

ifname);

1199

1123

}

1200

1124

return false;

1201

1125

}

1202

1126

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

1203

1127

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

1204

1128

if(debug){

1205

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

1206

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

1129

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

1130

ifname);

1207

1131

}

1208

1132

return true;

1209

1133

}

1210

1134

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

1211

1135

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

1212

1136

if(debug){

1213

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1214

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

1137

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

1138

ifname);

1215

1139

}

1216

1140

return false;

1217

1141

}

1218

1142

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

1219

1143

if(ifr->ifr_flags & IFF_NOARP){

1220

1144

if(debug){

1221

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

1222

ifname);

1145

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

1223

1146

}

1224

1147

return false;

1225

1148

}

1226

1149

1227

1150

/* Accept this device */

1228

1151

if(debug){

1229

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

1152

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

1230

1153

}

1231

1154

return true;

1232

1155

}

1237

1160

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

1238

1161

*/

1239

1162

int good_interface(const struct dirent *if_entry){

1163

int ret;

1240

1164

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

1241

1165

return 0;

1242

1166

}

1243

1244

1167

struct ifreq ifr;

1168

1245

1169

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

1170

return 0;

1251

1171

}

1252

1172

1257

1177

}

1258

1178

1259

1179

/*

1260

* This function determines if a network interface is up.

1180

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

1181

* corresponds to an acceptable network device which is up.

1182

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

1261

1183

*/

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

}

1184

int up_interface(const struct dirent *if_entry){

1185

ssize_t ssret;

1186

char *flagname = NULL;

1187

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

1188

return 0;

1189

}

1190

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

1191

if_entry->d_name);

1192

if(ret < 0){

1193

perror_plus("asprintf");

1194

return 0;

1195

}

1196

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

1197

if(flags_fd == -1){

1198

perror_plus("open");

1199

free(flagname);

1200

return 0;

1201

}

1202

free(flagname);

1203

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

1204

/* read line from flags_fd */

1205

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

1206

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

1207

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

1208

if(flagstring == NULL){

1209

perror_plus("malloc");

1210

close(flags_fd);

1211

return 0;

1212

}

1213

while(to_read > 0){

1214

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

1215

(size_t)to_read));

1216

if(ssret == -1){

1217

perror_plus("read");

1218

free(flagstring);

1219

close(flags_fd);

1220

return 0;

1221

}

1222

to_read -= ssret;

1223

if(ssret == 0){

1224

break;

1225

}

1226

}

1227

close(flags_fd);

1228

intmax_t tmpmax;

1229

char *tmp;

1230

errno = 0;

1231

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

1232

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

1233

and not (isspace(*tmp)))

1234

or tmpmax != (ifreq_flags)tmpmax){

1235

if(debug){

1236

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

1237

flagstring, if_entry->d_name);

1238

}

1239

free(flagstring);

1240

return 0;

1241

}

1242

free(flagstring);

1243

ifreq_flags flags = (ifreq_flags)tmpmax;

1244

/* Reject the loopback device */

1245

if(flags & IFF_LOOPBACK){

1246

if(debug){

1247

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

1248

if_entry->d_name);

1249

}

1250

return 0;

1251

}

1274

1252

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;

1253

/* Reject down interfaces */

1254

if(not (flags & IFF_UP)){

1255

return 0;

1286

1256

}

1287

1257

1288

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

1258

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

1259

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

1260

if(debug){

1261

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

1262

if_entry->d_name);

1263

}

1264

return 1;

1265

}

1266

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

1267

if(not (flags & IFF_BROADCAST)){

1268

if(debug){

1269

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

1270

if_entry->d_name);

1271

}

1272

return 0;

1273

}

1274

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

1275

if(flags & IFF_NOARP){

1276

if(debug){

1277

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

1278

if_entry->d_name);

1279

}

1280

return 0;

1281

}

1282

/* Accept this device */

1283

if(debug){

1284

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

1285

if_entry->d_name);

1286

}

1287

return 1;

1289

1288

}

1290

1289

1291

1290

int notdotentries(const struct dirent *direntry){

1302

1301

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

1303

1302

int runnable_hook(const struct dirent *direntry){

1304

1303

int ret;

1305

size_t sret;

1306

1304

struct stat st;

1307

1305

1308

1306

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

1310

1308

return 0;

1311

1309

}

1312

1310

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);

1311

/* Save pointer to last character */

1312

char *end = strchr(direntry->d_name, '\0')-1;

1313

1314

if(*end == '~'){

1315

/* Backup name~ */

1316

return 0;

1317

}

1318

1319

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

1320

and (*end == '#')){

1321

/* Temporary #name# */

1322

return 0;

1323

}

1324

1325

/* XXX more rules here */

1326

1327

ret = stat(direntry->d_name, &st);

1334

1328

if(ret == -1){

1335

1329

if(debug){

1336

perror_plus("Could not stat hook");

1330

perror_plus("Could not stat plugin");

1337

1331

}

1338

1332

return 0;

1339

1333

}

1340

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

1334

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

1341

1335

/* Not a regular file */

1342

if(debug){

1343

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

1344

direntry->d_name);

1345

}

1346

1336

return 0;

1347

1337

}

1348

1338

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

1349

1339

/* Not executable */

1350

if(debug){

1351

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

1352

direntry->d_name);

1353

}

1354

1340

return 0;

1355

1341

}

1356

if(debug){

1357

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

1358

direntry->d_name);

1359

}

1360

1342

return 1;

1361

1343

}

1362

1344

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

mandos_context *mc){

1345

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1365

1346

int ret;

1366

1347

struct timespec now;

1367

1348

struct timespec waited_time;

1368

1349

intmax_t block_time;

1369

1350

1370

1351

while(true){

1371

if(mc->current_server == NULL){

1352

if(mc.current_server == NULL){

1372

1353

if (debug){

1373

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

1374

" No timeout!\n");

1354

fprintf(stderr,

1355

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

1375

1356

}

1376

1357

ret = avahi_simple_poll_iterate(s, -1);

1377

1358

} else {

1378

1359

if (debug){

1379

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

1380

" it, or wait\n");

1360

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

1361

" or wait\n");

1381

1362

}

1382

1363

/* the current time */

1383

1364

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1388

1369

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

1389

1370

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

1390

1371

waited_time.tv_sec = (now.tv_sec

1391

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

1372

- mc.current_server->last_seen.tv_sec);

1392

1373

waited_time.tv_nsec = (now.tv_nsec

1393

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

1374

- mc.current_server->last_seen.tv_nsec);

1394

1375

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

1395

1376

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

1396

1377

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

1399

1380

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

1400

1381

1401

1382

if (debug){

1402

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

1403

block_time);

1383

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

1404

1384

}

1405

1385

1406

1386

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);

1387

ret = start_mandos_communication(mc.current_server->ip,

1388

mc.current_server->port,

1389

mc.current_server->if_index,

1390

mc.current_server->af);

1411

1391

if(ret == 0){

1412

avahi_simple_poll_quit(s);

1392

avahi_simple_poll_quit(mc.simple_poll);

1413

1393

return 0;

1414

1394

}

1415

1395

ret = clock_gettime(CLOCK_MONOTONIC,

1416

&mc->current_server->last_seen);

1396

&mc.current_server->last_seen);

1417

1397

if(ret == -1){

1418

1398

perror_plus("clock_gettime");

1419

1399

return -1;

1420

1400

}

1421

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

1401

mc.current_server = mc.current_server->next;

1422

1402

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

1423

1403

servers, but don't block */

1424

1404

}

1426

1406

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

1427

1407

}

1428

1408

if(ret != 0){

1429

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

1409

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

1430

1410

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

1431

1411

}

1432

1412

}

1433

1413

}

1434

1414

}

1435

1415

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

1416

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

1417

AvahiSServiceBrowser *sb = NULL;

1799

error_t ret_errno;

1418

int error;

1800

1419

int ret;

1801

1420

intmax_t tmpmax;

1802

1421

char *tmp;

1803

1422

int exitcode = EXIT_SUCCESS;

1804

char *interfaces_to_take_down = NULL;

1805

size_t interfaces_to_take_down_size = 0;

1423

const char *interface = "";

1424

struct ifreq network;

1425

int sd = -1;

1426

bool take_down_interface = false;

1427

uid_t uid;

1428

gid_t gid;

1806

1429

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

1807

1430

bool tempdir_created = false;

1808

1431

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1809

1432

const char *seckey = PATHDIR "/" SECKEY;

1810

1433

const char *pubkey = PATHDIR "/" PUBKEY;

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1813

1434

1814

1435

bool gnutls_initialized = false;

1815

1436

bool gpgme_initialized = false;

1877

1498

.group = 2 },

1878

1499

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

1879

1500

.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",

1501

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

1885

1502

.group = 2 },

1886

1503

/*

1887

1504

* These reproduce what we would get without ARGP_NO_HELP

1906

1523

connect_to = arg;

1907

1524

break;

1908

1525

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

}

1526

interface = arg;

1914

1527

break;

1915

1528

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

1916

1529

seckey = arg;

1945

1558

argp_error(state, "Bad retry interval");

1946

1559

}

1947

1560

break;

1948

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

1949

hookdir = arg;

1950

break;

1951

1561

/*

1952

1562

* These reproduce what we would get without ARGP_NO_HELP

1953

1563

*/

1959

1569

argp_state_help(state, state->out_stream,

1960

1570

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1961

1571

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

1962

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

1572

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

1963

1573

exit(argp_err_exit_status);

1964

1574

break;

1965

1575

default:

1992

1602

{

1993

1603

/* Work around Debian bug #633582:

1994

1604

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

1605

struct stat st;

1995

1606

1996

1607

/* 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");

1608

errno = 0;

1609

ret = seteuid(0);

1610

if(ret == -1){

1611

perror_plus("seteuid");

1612

}

1613

1614

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

1615

int seckey_fd = open(seckey, O_RDONLY);

1616

if(seckey_fd == -1){

1617

perror_plus("open");

1618

} else {

1619

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

1620

if(ret == -1){

1621

perror_plus("fstat");

1622

} else {

1623

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

1624

ret = fchown(seckey_fd, uid, gid);

1625

if(ret == -1){

1626

perror_plus("fchown");

1627

}

1628

}

1629

}

1630

TEMP_FAILURE_RETRY(close(seckey_fd));

1631

}

1632

}

1633

1634

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

1635

int pubkey_fd = open(pubkey, O_RDONLY);

1636

if(pubkey_fd == -1){

1637

perror_plus("open");

1638

} else {

1639

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

1640

if(ret == -1){

1641

perror_plus("fstat");

1642

} else {

1643

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

1644

ret = fchown(pubkey_fd, uid, gid);

1645

if(ret == -1){

1646

perror_plus("fchown");

1647

}

1648

}

1649

}

1650

TEMP_FAILURE_RETRY(close(pubkey_fd));

1651

}

1652

}

1653

1654

/* Lower privileges */

1655

errno = 0;

1656

ret = seteuid(uid);

1657

if(ret == -1){

1658

perror_plus("seteuid");

1659

}

1660

}

1661

1662

/* Find network hooks and run them */

1663

{

1664

struct dirent **direntries;

1665

struct dirent *direntry;

1666

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

1667

alphasort);

1668

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

1669

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

1670

direntry = direntries[0];

1671

char *fullname = NULL;

1672

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

1673

direntry->d_name);

1674

if(ret < 0){

1675

perror_plus("asprintf");

1676

continue;

1677

}

1678

pid_t hook_pid = fork();

1679

if(hook_pid == 0){

1680

/* Child */

1681

dup2(devnull, STDIN_FILENO);

1682

close(devnull);

1683

dup2(STDERR_FILENO, STDOUT_FILENO);

1684

setenv("DEVICE", interface, 1);

1685

setenv("VERBOSE", debug ? "1" : "0", 1);

1686

setenv("MODE", "start", 1);

1687

/* setenv( XXX more here */

1688

ret = execl(fullname, direntry->d_name, "start");

1689

perror_plus("execl");

1690

}

1691

free(fullname);

1692

if(quit_now){

2070

1693

goto end;

2071

1694

}

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;

2080

}

1695

}

1696

close(devnull);

2081

1697

}

2082

1698

2083

1699

if(not debug){

2084

1700

avahi_set_log_function(empty_log);

2085

1701

}

2086

1702

1703

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

1704

struct dirent **direntries;

1705

ret = scandir(sys_class_net, &direntries, good_interface,

1706

alphasort);

1707

if(ret >= 1){

1708

/* Pick the first good interface */

1709

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

1710

if(debug){

1711

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

1712

}

1713

if(interface == NULL){

1714

perror_plus("malloc");

1715

free(direntries);

1716

exitcode = EXIT_FAILURE;

1717

goto end;

1718

}

1719

free(direntries);

1720

} else {

1721

free(direntries);

1722

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

1723

exitcode = EXIT_FAILURE;

1724

goto end;

1725

}

1726

}

1727

2087

1728

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

2088

1729

from the signal handler */

2089

1730

/* Initialize the pseudo-RNG for Avahi */

2090

1731

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");

1732

mc.simple_poll = avahi_simple_poll_new();

1733

if(mc.simple_poll == NULL){

1734

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

2095

1735

exitcode = EX_UNAVAILABLE;

2096

1736

goto end;

2097

1737

}

2159

1799

}

2160

1800

}

2161

1801

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;

1802

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

1803

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

1804

if_index = (AvahiIfIndex) if_nametoindex(interface);

1805

if(if_index == 0){

1806

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

1807

exitcode = EX_UNAVAILABLE;

1808

goto end;

1809

}

1810

1811

if(quit_now){

1812

goto end;

1813

}

1814

1815

/* Re-raise priviliges */

1816

errno = 0;

1817

ret = seteuid(0);

1818

if(ret == -1){

1819

perror_plus("seteuid");

1820

}

1821

1822

#ifdef __linux__

1823

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1824

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

1825

ret = klogctl(8, NULL, 5);

1826

bool restore_loglevel = true;

1827

if(ret == -1){

1828

restore_loglevel = false;

1829

perror_plus("klogctl");

1830

}

1831

#endif /* __linux__ */

1832

1833

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1834

if(sd < 0){

1835

perror_plus("socket");

1836

exitcode = EX_OSERR;

1837

#ifdef __linux__

1838

if(restore_loglevel){

1839

ret = klogctl(7, NULL, 0);

1840

if(ret == -1){

1841

perror_plus("klogctl");

1842

}

1843

}

1844

#endif /* __linux__ */

1845

/* Lower privileges */

1846

errno = 0;

1847

ret = seteuid(uid);

1848

if(ret == -1){

1849

perror_plus("seteuid");

1850

}

1851

goto end;

1852

}

1853

strcpy(network.ifr_name, interface);

1854

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

1855

if(ret == -1){

1856

perror_plus("ioctl SIOCGIFFLAGS");

1857

#ifdef __linux__

1858

if(restore_loglevel){

1859

ret = klogctl(7, NULL, 0);

1860

if(ret == -1){

1861

perror_plus("klogctl");

1862

}

1863

}

1864

#endif /* __linux__ */

1865

exitcode = EX_OSERR;

1866

/* Lower privileges */

1867

errno = 0;

1868

ret = seteuid(uid);

1869

if(ret == -1){

1870

perror_plus("seteuid");

1871

}

1872

goto end;

1873

}

1874

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

1875

network.ifr_flags |= IFF_UP;

1876

take_down_interface = true;

1877

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

1878

if(ret == -1){

1879

take_down_interface = false;

1880

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1881

exitcode = EX_OSERR;

1882

#ifdef __linux__

1883

if(restore_loglevel){

1884

ret = klogctl(7, NULL, 0);

1885

if(ret == -1){

1886

perror_plus("klogctl");

2208

1887

}

2209

1888

}

1889

#endif /* __linux__ */

1890

/* Lower privileges */

1891

errno = 0;

1892

ret = seteuid(uid);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

goto end;

1897

}

1898

}

1899

/* Sleep checking until interface is running.

1900

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

1901

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

1902

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

1903

if(ret == -1){

1904

perror_plus("ioctl SIOCGIFFLAGS");

1905

} else if(network.ifr_flags & IFF_RUNNING){

2210

1906

break;

2211

1907

}

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);

1908

struct timespec sleeptime = { .tv_nsec = 250000000 };

1909

ret = nanosleep(&sleeptime, NULL);

1910

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

1911

perror_plus("nanosleep");

1912

}

1913

}

1914

if(not take_down_interface){

1915

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

1916

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

1917

if(ret == -1){

1918

perror_plus("close");

1919

}

1920

}

1921

#ifdef __linux__

1922

if(restore_loglevel){

1923

/* Restores kernel loglevel to default */

1924

ret = klogctl(7, NULL, 0);

1925

if(ret == -1){

1926

perror_plus("klogctl");

1927

}

1928

}

1929

#endif /* __linux__ */

1930

/* Lower privileges */

1931

errno = 0;

1932

if(take_down_interface){

1933

/* Lower privileges */

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

1938

} else {

1939

/* Lower privileges permanently */

1940

ret = setuid(uid);

1941

if(ret == -1){

1942

perror_plus("setuid");

1943

}

1944

}

2237

1945

}

2238

1946

2239

1947

if(quit_now){

2240

1948

goto end;

2241

1949

}

2242

1950

2243

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

1951

ret = init_gnutls_global(pubkey, seckey);

2244

1952

if(ret == -1){

2245

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

1953

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

2246

1954

exitcode = EX_UNAVAILABLE;

2247

1955

goto end;

2248

1956

} else {

2263

1971

goto end;

2264

1972

}

2265

1973

2266

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

2267

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

1974

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

1975

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

2268

1976

exitcode = EX_UNAVAILABLE;

2269

1977

goto end;

2270

1978

} else {

2279

1987

/* Connect directly, do not use Zeroconf */

2280

1988

/* (Mainly meant for debugging) */

2281

1989

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

2282

2283

1990

if(address == NULL){

2284

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

1991

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

2285

1992

exitcode = EX_USAGE;

2286

1993

goto end;

2287

1994

}

2290

1997

goto end;

2291

1998

}

2292

1999

2293

in_port_t port;

2000

uint16_t port;

2294

2001

errno = 0;

2295

2002

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

2296

2003

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");

2004

or tmpmax != (uint16_t)tmpmax){

2005

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

2299

2006

exitcode = EX_USAGE;

2300

2007

goto end;

2301

2008

}

2302

2009

2303

2010

if(quit_now){

2304

2011

goto end;

2305

2012

}

2306

2013

2307

port = (in_port_t)tmpmax;

2014

port = (uint16_t)tmpmax;

2308

2015

*address = '\0';

2309

2016

/* Colon in address indicates IPv6 */

2310

2017

int af;

2326

2033

}

2327

2034

2328

2035

while(not quit_now){

2329

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

2330

&mc);

2036

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

2331

2037

if(quit_now or ret == 0){

2332

2038

break;

2333

2039

}

2334

2040

if(debug){

2335

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

2336

(int)retry_interval);

2041

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

2042

(int)retry_interval);

2337

2043

}

2338

sleep((unsigned int)retry_interval);

2044

sleep((int)retry_interval);

2339

2045

}

2340

2046

2341

2047

if (not quit_now){

2359

2065

config.publish_domain = 0;

2360

2066

2361

2067

/* Allocate a new server */

2362

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2363

&config, NULL, NULL, &ret_errno);

2068

mc.server = avahi_server_new(avahi_simple_poll_get

2069

(mc.simple_poll), &config, NULL,

2070

NULL, &error);

2364

2071

2365

2072

/* Free the Avahi configuration data */

2366

2073

avahi_server_config_free(&config);

2368

2075

2369

2076

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

2370

2077

if(mc.server == NULL){

2371

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

2372

avahi_strerror(ret_errno));

2078

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

2079

avahi_strerror(error));

2373

2080

exitcode = EX_UNAVAILABLE;

2374

2081

goto end;

2375

2082

}

2381

2088

/* Create the Avahi service browser */

2382

2089

sb = avahi_s_service_browser_new(mc.server, if_index,

2383

2090

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2384

NULL, 0, browse_callback,

2385

(void *)&mc);

2091

NULL, 0, browse_callback, NULL);

2386

2092

if(sb == NULL){

2387

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

2388

avahi_strerror(avahi_server_errno(mc.server)));

2093

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

2094

avahi_strerror(avahi_server_errno(mc.server)));

2389

2095

exitcode = EX_UNAVAILABLE;

2390

2096

goto end;

2391

2097

}

2397

2103

/* Run the main loop */

2398

2104

2399

2105

if(debug){

2400

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

2106

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

2401

2107

}

2402

2108

2403

ret = avahi_loop_with_timeout(simple_poll,

2404

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

2109

ret = avahi_loop_with_timeout(mc.simple_poll,

2110

(int)(retry_interval * 1000));

2405

2111

if(debug){

2406

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

2407

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

2112

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

2113

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

2408

2114

}

2409

2115

2410

2116

end:

2411

2117

2412

2118

if(debug){

2413

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

2119

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

2414

2120

}

2415

2121

2416

2122

/* Cleanup things */

2417

free(mc.interfaces);

2418

2419

2123

if(sb != NULL)

2420

2124

avahi_s_service_browser_free(sb);

2421

2125

2422

2126

if(mc.server != NULL)

2423

2127

avahi_server_free(mc.server);

2424

2128

2425

if(simple_poll != NULL)

2426

avahi_simple_poll_free(simple_poll);

2129

if(mc.simple_poll != NULL)

2130

avahi_simple_poll_free(mc.simple_poll);

2427

2131

2428

2132

if(gnutls_initialized){

2429

2133

gnutls_certificate_free_credentials(mc.cred);

2434

2138

if(gpgme_initialized){

2435

2139

gpgme_release(mc.ctx);

2436

2140

}

2437

2141

2438

2142

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

2439

2143

has seen */

2440

2144

if(mc.current_server != NULL){

2446

2150

}

2447

2151

}

2448

2152

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");

2153

/* XXX run network hooks "stop" here */

2154

2155

/* Take down the network interface */

2156

if(take_down_interface){

2157

/* Re-raise priviliges */

2158

errno = 0;

2159

ret = seteuid(0);

2160

if(ret == -1){

2161

perror_plus("seteuid");

2162

}

2163

if(geteuid() == 0){

2164

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

2165

if(ret == -1){

2166

perror_plus("ioctl SIOCGIFFLAGS");

2167

} else if(network.ifr_flags & IFF_UP) {

2168

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

2169

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

2170

if(ret == -1){

2171

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2467

2172

}

2468

2173

}

2469

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

2470

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

2471

" down\n");

2174

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

2175

if(ret == -1){

2176

perror_plus("close");

2177

}

2178

/* Lower privileges permanently */

2179

errno = 0;

2180

ret = setuid(uid);

2181

if(ret == -1){

2182

perror_plus("setuid");

2472

2183

}

2473

2184

}

2474

2475

lower_privileges_permanently();

2476

2185

}

2477

2186

2478

free(interfaces_to_take_down);

2479

free(interfaces_hooks);

2480

2481

2187

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

2482

2188

if(tempdir_created){

2483

2189

struct dirent **direntries = NULL;

2496

2202

}

2497

2203

ret = remove(fullname);

2498

2204

if(ret == -1){

2499

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

2500

strerror(errno));

2205

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

2206

strerror(errno));

2501

2207

}

2502

2208

free(fullname);

2503

2209

}