/mandos/trunk : revision 616

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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 */

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#include <stdint.h> /* uint16_t, uint32_t, intptr_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() */

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

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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() */

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

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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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#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_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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uint16_t port;

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

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AvahiSimplePoll *simple_poll;

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

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}

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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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if(buffer == NULL){

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}

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

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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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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 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 -1;

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return false;

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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 -1;

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return false;

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}

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/* Special case of first server */

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if (mc.current_server == NULL){

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if(*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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mc.current_server = new_server;

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*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 = mc.current_server;

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

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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->prev->next = new_server;

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mc.current_server->prev = new_server;

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(*current_server)->prev = new_server;

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}

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

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return -1;

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return false;

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}

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return 0;

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return true;

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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,

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const char *pubkey, const char *tempdir){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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return false;

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}

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}

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if(debug){

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

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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return false;

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}

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*/

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static ssize_t pgp_packet_decrypt(const char *cryptotext,

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size_t crypto_size,

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char **plaintext){

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char **plaintext,

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mandos_context *mc){

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gpgme_data_t dh_crypto, dh_plain;

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gpgme_error_t rc;

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ssize_t ret;

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ssize_t plaintext_length = 0;

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if(debug){

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

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

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}

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

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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

340

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0);

341

362

if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return -1;

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}

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367

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

348

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rc = gpgme_data_new(&dh_plain);

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370

if(rc != GPG_ERR_NO_ERROR){

350

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

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gpgme_strsource(rc), gpgme_strerror(rc));

371

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

372

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

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gpgme_strsource(rc), gpgme_strerror(rc));

352

374

gpgme_data_release(dh_crypto);

353

375

return -1;

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376

}

355

377

356

378

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

357

379

data buffer */

358

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

380

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

359

381

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

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384

plaintext_length = -1;

363

385

if(debug){

364

386

gpgme_decrypt_result_t result;

365

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

366

388

if(result == NULL){

367

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

389

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

368

390

} else {

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

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);

373

395

if(result->file_name != NULL){

374

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

396

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

375

397

}

376

398

gpgme_recipient_t recipient;

377

399

recipient = result->recipients;

378

400

while(recipient != NULL){

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");

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");

385

408

recipient = recipient->next;

386

409

}

387

410

}

390

413

}

391

414

392

415

if(debug){

393

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

416

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

394

417

}

395

418

396

419

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

403

426

*plaintext = NULL;

404

427

while(true){

405

428

plaintext_capacity = incbuffer(plaintext,

406

(size_t)plaintext_length,

407

plaintext_capacity);

429

(size_t)plaintext_length,

430

plaintext_capacity);

408

431

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

412

435

}

413

436

414

437

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

427

450

}

428

451

429

452

if(debug){

430

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

453

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

431

454

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

432

455

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

433

456

}

445

468

}

446

469

447

470

static const char * safer_gnutls_strerror(int value){

448

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

449

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

450

472

if(ret == NULL)

451

473

ret = "(unknown)";

452

474

return ret;

455

477

/* GnuTLS log function callback */

456

478

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

457

479

const char* string){

458

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

480

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

459

481

}

460

482

461

483

static int init_gnutls_global(const char *pubkeyfilename,

462

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

463

486

int ret;

464

487

465

488

if(debug){

466

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

489

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

467

490

}

468

491

469

492

ret = gnutls_global_init();

470

493

if(ret != GNUTLS_E_SUCCESS){

471

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

472

safer_gnutls_strerror(ret));

494

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

495

safer_gnutls_strerror(ret));

473

496

return -1;

474

497

}

475

498

482

505

}

483

506

484

507

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

486

509

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

510

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

511

safer_gnutls_strerror(ret));

489

512

gnutls_global_deinit();

490

513

return -1;

491

514

}

492

515

493

516

if(debug){

494

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

495

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

496

seckeyfilename);

517

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

518

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

519

pubkeyfilename,

520

seckeyfilename);

497

521

}

498

522

499

523

ret = gnutls_certificate_set_openpgp_key_file

500

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

501

525

GNUTLS_OPENPGP_FMT_BASE64);

502

526

if(ret != GNUTLS_E_SUCCESS){

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));

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));

508

532

goto globalfail;

509

533

}

510

534

511

535

/* GnuTLS server initialization */

512

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

513

537

if(ret != GNUTLS_E_SUCCESS){

514

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

515

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

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

516

541

goto globalfail;

517

542

}

518

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

543

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

519

544

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

545

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

546

safer_gnutls_strerror(ret));

522

547

goto globalfail;

523

548

}

524

549

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

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

526

551

527

552

return 0;

528

553

529

554

globalfail:

530

555

531

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

532

557

gnutls_global_deinit();

533

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

534

559

return -1;

535

560

}

536

561

537

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

538

564

int ret;

539

565

/* GnuTLS session creation */

540

566

do {

544

570

}

545

571

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

546

572

if(ret != GNUTLS_E_SUCCESS){

547

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

548

safer_gnutls_strerror(ret));

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

549

576

}

550

577

551

578

{

552

579

const char *err;

553

580

do {

554

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

581

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

555

582

if(quit_now){

556

583

gnutls_deinit(*session);

557

584

return -1;

558

585

}

559

586

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

560

587

if(ret != GNUTLS_E_SUCCESS){

561

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

562

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

563

safer_gnutls_strerror(ret));

588

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

589

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

590

safer_gnutls_strerror(ret));

564

591

gnutls_deinit(*session);

565

592

return -1;

566

593

}

568

595

569

596

do {

570

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

571

mc.cred);

598

mc->cred);

572

599

if(quit_now){

573

600

gnutls_deinit(*session);

574

601

return -1;

575

602

}

576

603

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

577

604

if(ret != GNUTLS_E_SUCCESS){

578

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

579

safer_gnutls_strerror(ret));

605

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

606

safer_gnutls_strerror(ret));

580

607

gnutls_deinit(*session);

581

608

return -1;

582

609

}

584

611

/* ignore client certificate if any. */

585

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

586

613

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

588

615

589

616

return 0;

590

617

}

594

621

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

595

622

596

623

/* Called when a Mandos server is found */

597

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

624

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

598

625

AvahiIfIndex if_index,

599

int af){

626

int af, mandos_context *mc){

600

627

int ret, tcp_sd = -1;

601

628

ssize_t sret;

602

629

union {

627

654

pf = PF_INET;

628

655

break;

629

656

default:

630

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

657

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

631

658

errno = EINVAL;

632

659

return -1;

633

660

}

634

661

635

ret = init_gnutls_session(&session);

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);

636

695

if(ret != 0){

637

696

return -1;

638

697

}

639

698

640

699

if(debug){

641

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

642

"\n", ip, port);

700

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

701

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

643

702

}

644

703

645

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

671

730

}

672

731

if(ret == 0){

673

732

int e = errno;

674

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

733

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

675

734

errno = e;

676

735

goto mandos_end;

677

736

}

678

737

if(af == AF_INET6){

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

738

to.in6.sin6_port = htons(port);

683

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

740

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

685

-Wunreachable-code*/

741

-Wunreachable-code*/

686

742

if(if_index == AVAHI_IF_UNSPEC){

687

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

688

" without a network interface\n");

743

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

744

" incomplete without a network interface\n");

689

745

errno = EINVAL;

690

746

goto mandos_end;

691

747

}

709

765

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

710

766

perror_plus("if_indextoname");

711

767

} else {

712

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

713

ip, interface, port);

768

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

769

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

714

770

}

715

771

} else {

716

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

717

port);

772

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

773

ip, (uintmax_t)port);

718

774

}

719

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

720

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

730

786

perror_plus("inet_ntop");

731

787

} else {

732

788

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

733

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

789

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

734

790

}

735

791

}

736

792

}

764

820

while(true){

765

821

size_t out_size = strlen(out);

766

822

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

767

out_size - written));

823

out_size - written));

768

824

if(ret == -1){

769

825

int e = errno;

770

826

perror_plus("write");

790

846

}

791

847

792

848

if(debug){

793

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

849

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

794

850

}

795

851

796

852

if(quit_now){

798

854

goto mandos_end;

799

855

}

800

856

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

857

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

858

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

859

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

860

gnutls_transport_set_ptr(session,

861

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

803

862

804

863

if(quit_now){

805

864

errno = EINTR;

816

875

817

876

if(ret != GNUTLS_E_SUCCESS){

818

877

if(debug){

819

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

878

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

820

879

gnutls_perror(ret);

821

880

}

822

881

errno = EPROTO;

826

885

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

827

886

828

887

if(debug){

829

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

830

ip);

888

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

889

" %s\n", ip);

831

890

}

832

891

833

892

while(true){

838

897

}

839

898

840

899

buffer_capacity = incbuffer(&buffer, buffer_length,

841

buffer_capacity);

900

buffer_capacity);

842

901

if(buffer_capacity == 0){

843

902

int e = errno;

844

903

perror_plus("incbuffer");

871

930

}

872

931

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

873

932

if(ret < 0){

874

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

933

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

934

"***\n");

875

935

gnutls_perror(ret);

876

936

errno = EPROTO;

877

937

goto mandos_end;

878

938

}

879

939

break;

880

940

default:

881

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

882

" encrypted session with Mandos server\n");

941

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

942

" encrypted session with Mandos server\n");

883

943

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

944

errno = EIO;

885

945

goto mandos_end;

890

950

}

891

951

892

952

if(debug){

893

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

953

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

894

954

}

895

955

896

956

if(quit_now){

908

968

909

969

if(buffer_length > 0){

910

970

ssize_t decrypted_buffer_size;

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

971

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

972

&decrypted_buffer, mc);

914

973

if(decrypted_buffer_size >= 0){

915

974

916

975

written = 0;

926

985

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

927

986

int e = errno;

928

987

if(debug){

929

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

930

strerror(errno));

988

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

989

strerror(errno));

931

990

}

932

991

errno = e;

933

992

goto mandos_end;

977

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

978

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

979

1038

flags,

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1039

void* mc){

1040

if(r == NULL){

1041

return;

1042

}

982

1043

983

1044

/* Called whenever a service has been resolved successfully or

984

1045

timed out */

990

1051

switch(event){

991

1052

default:

992

1053

case AVAHI_RESOLVER_FAILURE:

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)));

1054

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

1055

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

1056

domain,

1057

avahi_strerror(avahi_server_errno

1058

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

996

1059

break;

997

1060

998

1061

case AVAHI_RESOLVER_FOUND:

1000

1063

char ip[AVAHI_ADDRESS_STR_MAX];

1001

1064

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

1002

1065

if(debug){

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);

1066

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

1067

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

1068

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

1006

1069

}

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1070

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

1071

interface,

1072

avahi_proto_to_af(proto),

1073

mc);

1009

1074

if(ret == 0){

1010

avahi_simple_poll_quit(mc.simple_poll);

1075

avahi_simple_poll_quit(simple_poll);

1011

1076

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1077

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

1078

avahi_proto_to_af(proto),

1079

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

1080

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

1081

" list\n", name);

1082

}

1014

1083

}

1015

1084

}

1016

1085

}

1026

1095

const char *domain,

1027

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1028

1097

flags,

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1098

void* mc){

1099

if(b == NULL){

1100

return;

1101

}

1031

1102

1032

1103

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

1033

1104

is removed from the LAN */

1040

1111

default:

1041

1112

case AVAHI_BROWSER_FAILURE:

1042

1113

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1114

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

1115

avahi_strerror(avahi_server_errno

1116

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

1117

avahi_simple_poll_quit(simple_poll);

1046

1118

return;

1047

1119

1048

1120

case AVAHI_BROWSER_NEW:

1051

1123

the callback function is called the Avahi server will free the

1052

1124

resolver for us. */

1053

1125

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)));

1126

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

1127

interface, protocol, name, type,

1128

domain, protocol, 0,

1129

resolve_callback, mc) == NULL)

1130

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

1131

" %s\n", name,

1132

avahi_strerror(avahi_server_errno

1133

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

1059

1134

break;

1060

1135

1061

1136

case AVAHI_BROWSER_REMOVE:

1064

1139

case AVAHI_BROWSER_ALL_FOR_NOW:

1065

1140

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1066

1141

if(debug){

1067

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

1142

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

1143

" searching...\n");

1068

1144

}

1069

1145

break;

1070

1146

}

1079

1155

signal_received = sig;

1080

1156

int old_errno = errno;

1081

1157

/* set main loop to exit */

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1158

if(simple_poll != NULL){

1159

avahi_simple_poll_quit(simple_poll);

1084

1160

}

1085

1161

errno = old_errno;

1086

1162

}

1087

1163

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;

1164

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

1095

1165

int ret;

1096

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

1097

return 0;

1098

}

1166

error_t ret_errno;

1167

1099

1168

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

1100

1169

if(s < 0){

1170

ret_errno = errno;

1101

1171

perror_plus("socket");

1102

return 0;

1172

errno = ret_errno;

1173

return false;

1103

1174

}

1104

struct ifreq ifr;

1105

strcpy(ifr.ifr_name, if_entry->d_name);

1106

ret = ioctl(s, SIOCGIFFLAGS, &ifr);

1175

strcpy(ifr->ifr_name, ifname);

1176

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1107

1177

if(ret == -1){

1108

1178

if(debug){

1179

ret_errno = errno;

1109

1180

perror_plus("ioctl SIOCGIFFLAGS");

1181

errno = ret_errno;

1110

1182

}

1111

return 0;

1183

return false;

1112

1184

}

1185

return true;

1186

}

1187

1188

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

1189

1113

1190

/* Reject the loopback device */

1114

if(ifr.ifr_flags & IFF_LOOPBACK){

1191

if(ifr->ifr_flags & IFF_LOOPBACK){

1115

1192

if(debug){

1116

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

1117

if_entry->d_name);

1193

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

1194

ifname);

1118

1195

}

1119

return 0;

1196

return false;

1120

1197

}

1121

1198

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

1122

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

1199

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

1123

1200

if(debug){

1124

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

1125

if_entry->d_name);

1201

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

1202

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

1126

1203

}

1127

return 1;

1204

return true;

1128

1205

}

1129

1206

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

1130

if(not (ifr.ifr_flags & IFF_BROADCAST)){

1207

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

1131

1208

if(debug){

1132

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

1133

if_entry->d_name);

1209

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1210

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

1134

1211

}

1135

return 0;

1212

return false;

1136

1213

}

1137

1214

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

1138

if(ifr.ifr_flags & IFF_NOARP){

1215

if(ifr->ifr_flags & IFF_NOARP){

1139

1216

if(debug){

1140

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

1141

if_entry->d_name);

1217

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

1218

ifname);

1142

1219

}

1143

return 0;

1220

return false;

1144

1221

}

1222

1145

1223

/* Accept this device */

1146

1224

if(debug){

1147

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

1148

if_entry->d_name);

1225

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

1226

}

1227

return true;

1228

}

1229

1230

/*

1231

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

1232

* corresponds to an acceptable network device.

1233

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

1234

*/

1235

int good_interface(const struct dirent *if_entry){

1236

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

1237

return 0;

1238

}

1239

1240

struct ifreq ifr;

1241

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

1242

if(debug){

1243

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

1244

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

1245

}

1246

return 0;

1247

}

1248

1249

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

1250

return 0;

1149

1251

}

1150

1252

return 1;

1151

1253

}

1152

1254

1255

/*

1256

* This function determines if a network interface is up.

1257

*/

1258

bool interface_is_up(const char *interface){

1259

struct ifreq ifr;

1260

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

1261

if(debug){

1262

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

1263

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

1264

}

1265

return false;

1266

}

1267

1268

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

1269

}

1270

1271

/*

1272

* This function determines if a network interface is running

1273

*/

1274

bool interface_is_running(const char *interface){

1275

struct ifreq ifr;

1276

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

1277

if(debug){

1278

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

1279

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

1280

}

1281

return false;

1282

}

1283

1284

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

1285

}

1286

1153

1287

int notdotentries(const struct dirent *direntry){

1154

1288

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

1155

1289

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

1161

1295

return 1;

1162

1296

}

1163

1297

1164

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1298

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

1299

int runnable_hook(const struct dirent *direntry){

1300

int ret;

1301

size_t sret;

1302

struct stat st;

1303

1304

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

1305

/* Empty name? */

1306

return 0;

1307

}

1308

1309

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

1310

"abcdefghijklmnopqrstuvwxyz"

1311

"0123456789"

1312

"_-");

1313

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

1314

/* Contains non-allowed characters */

1315

if(debug){

1316

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

1317

direntry->d_name);

1318

}

1319

return 0;

1320

}

1321

1322

char *fullname = NULL;

1323

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

1324

if(ret < 0){

1325

perror_plus("asprintf");

1326

return 0;

1327

}

1328

1329

ret = stat(fullname, &st);

1330

if(ret == -1){

1331

if(debug){

1332

perror_plus("Could not stat hook");

1333

}

1334

return 0;

1335

}

1336

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

1337

/* Not a regular file */

1338

if(debug){

1339

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

1340

direntry->d_name);

1341

}

1342

return 0;

1343

}

1344

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

1345

/* Not executable */

1346

if(debug){

1347

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

1348

direntry->d_name);

1349

}

1350

return 0;

1351

}

1352

if(debug){

1353

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

1354

direntry->d_name);

1355

}

1356

return 1;

1357

}

1358

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

mandos_context *mc){

1165

1361

int ret;

1166

1362

struct timespec now;

1167

1363

struct timespec waited_time;

1168

1364

intmax_t block_time;

1169

1365

1170

1366

while(true){

1171

if(mc.current_server == NULL){

1367

if(mc->current_server == NULL){

1172

1368

if (debug){

1173

fprintf(stderr,

1174

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

1369

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

1370

" No timeout!\n");

1175

1371

}

1176

1372

ret = avahi_simple_poll_iterate(s, -1);

1177

1373

} else {

1178

1374

if (debug){

1179

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

1180

" or wait\n");

1375

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

1376

" it, or wait\n");

1181

1377

}

1182

1378

/* the current time */

1183

1379

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1188

1384

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

1189

1385

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

1190

1386

waited_time.tv_sec = (now.tv_sec

1191

- mc.current_server->last_seen.tv_sec);

1387

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

1192

1388

waited_time.tv_nsec = (now.tv_nsec

1193

- mc.current_server->last_seen.tv_nsec);

1389

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

1194

1390

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

1195

1391

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

1196

1392

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

1199

1395

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

1200

1396

1201

1397

if (debug){

1202

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

1398

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

1399

block_time);

1203

1400

}

1204

1401

1205

1402

if(block_time <= 0){

1206

ret = start_mandos_communication(mc.current_server->ip,

1207

mc.current_server->port,

1208

mc.current_server->if_index,

1209

mc.current_server->af);

1403

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

1404

mc->current_server->port,

1405

mc->current_server->if_index,

1406

mc->current_server->af, mc);

1210

1407

if(ret == 0){

1211

avahi_simple_poll_quit(mc.simple_poll);

1408

avahi_simple_poll_quit(s);

1212

1409

return 0;

1213

1410

}

1214

1411

ret = clock_gettime(CLOCK_MONOTONIC,

1215

&mc.current_server->last_seen);

1412

&mc->current_server->last_seen);

1216

1413

if(ret == -1){

1217

1414

perror_plus("clock_gettime");

1218

1415

return -1;

1219

1416

}

1220

mc.current_server = mc.current_server->next;

1417

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

1221

1418

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

1222

1419

servers, but don't block */

1223

1420

}

1225

1422

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

1226

1423

}

1227

1424

if(ret != 0){

1228

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

1425

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

1229

1426

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

1230

1427

}

1231

1428

}

1232

1429

}

1233

1430

}

1234

1431

1432

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

1433

error_t raise_privileges(void){

1434

error_t old_errno = errno;

1435

error_t ret_errno = 0;

1436

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

1437

ret_errno = errno;

1438

perror_plus("seteuid");

1439

}

1440

errno = old_errno;

1441

return ret_errno;

1442

}

1443

1444

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

1445

error_t raise_privileges_permanently(void){

1446

error_t old_errno = errno;

1447

error_t ret_errno = raise_privileges();

1448

if(ret_errno != 0){

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

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

1453

ret_errno = errno;

1454

perror_plus("seteuid");

1455

}

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

1460

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

1461

error_t lower_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

/* Lower privileges permanently */

1473

error_t lower_privileges_permanently(void){

1474

error_t old_errno = errno;

1475

error_t ret_errno = 0;

1476

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

1477

ret_errno = errno;

1478

perror_plus("setuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

const float delay){

1486

struct dirent **direntries;

1487

struct dirent *direntry;

1488

int ret;

1489

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

1490

alphasort);

1491

if(numhooks == -1){

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

1499

}

1500

} else {

1501

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

1502

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

1503

direntry = direntries[i];

1504

char *fullname = NULL;

1505

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

1506

if(ret < 0){

1507

perror_plus("asprintf");

1508

continue;

1509

}

1510

if(debug){

1511

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

1512

direntry->d_name);

1513

}

1514

pid_t hook_pid = fork();

1515

if(hook_pid == 0){

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1531

dup2(devnull, STDIN_FILENO);

1532

close(devnull);

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

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

1540

if(ret == -1){

1541

perror_plus("setenv");

1542

_exit(EX_OSERR);

1543

}

1544

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

1545

if(ret == -1){

1546

perror_plus("setenv");

1547

_exit(EX_OSERR);

1548

}

1549

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

1550

if(ret == -1){

1551

perror_plus("setenv");

1552

_exit(EX_OSERR);

1553

}

1554

char *delaystring;

1555

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

1556

if(ret == -1){

1557

perror_plus("asprintf");

1558

_exit(EX_OSERR);

1559

}

1560

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

1561

if(ret == -1){

1562

free(delaystring);

1563

perror_plus("setenv");

1564

_exit(EX_OSERR);

1565

}

1566

free(delaystring);

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

1578

} else {

1579

int status;

1580

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

1581

perror_plus("waitpid");

1582

free(fullname);

1583

continue;

1584

}

1585

if(WIFEXITED(status)){

1586

if(WEXITSTATUS(status) != 0){

1587

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

1588

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

1589

WEXITSTATUS(status));

1590

free(fullname);

1591

continue;

1592

}

1593

} else if(WIFSIGNALED(status)){

1594

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

1595

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

1596

WTERMSIG(status));

1597

free(fullname);

1598

continue;

1599

} else {

1600

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

1601

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

1602

free(fullname);

1603

continue;

1604

}

1605

}

1606

free(fullname);

1607

if(debug){

1608

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

1609

direntry->d_name);

1610

}

1611

}

1612

close(devnull);

1613

}

1614

return true;

1615

}

1616

1617

error_t bring_up_interface(const char *const interface,

1618

const float delay){

1619

int sd = -1;

1620

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

1623

struct ifreq network;

1624

unsigned int if_index = if_nametoindex(interface);

1625

if(if_index == 0){

1626

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

1627

errno = old_errno;

1628

return ENXIO;

1629

}

1630

1631

if(quit_now){

1632

errno = old_errno;

1633

return EINTR;

1634

}

1635

1636

if(not interface_is_up(interface)){

1637

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

1638

ret_errno = errno;

1639

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

1640

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

1641

return ret_errno;

1642

}

1643

network.ifr_flags |= IFF_UP;

1644

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

1647

ret_errno = errno;

1648

perror_plus("socket");

1649

errno = old_errno;

1650

return ret_errno;

1651

}

1652

1653

if(quit_now){

1654

close(sd);

1655

errno = old_errno;

1656

return EINTR;

1657

}

1658

1659

if(debug){

1660

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

1661

interface);

1662

}

1663

1664

/* Raise priviliges */

1665

raise_privileges();

1666

1667

#ifdef __linux__

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

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

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

1675

}

1676

#endif /* __linux__ */

1677

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

1678

ret_errno = errno;

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret_linux = klogctl(7, NULL, 0);

1682

if(ret_linux == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

1688

/* Lower privileges */

1689

lower_privileges();

1690

1691

/* Close the socket */

1692

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

1693

if(ret == -1){

1694

perror_plus("close");

1695

}

1696

1697

if(ret_setflags == -1){

1698

errno = ret_errno;

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1700

errno = old_errno;

1701

return ret_errno;

1702

}

1703

} else if(debug){

1704

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

1705

interface);

1706

}

1707

1708

/* Sleep checking until interface is running.

1709

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

1710

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

1711

if(interface_is_running(interface)){

1712

break;

1713

}

1714

struct timespec sleeptime = { .tv_nsec = 250000000 };

1715

ret = nanosleep(&sleeptime, NULL);

1716

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

1717

perror_plus("nanosleep");

1718

}

1719

}

1720

1721

errno = old_errno;

1722

return 0;

1723

}

1724

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

1730

struct ifreq network;

1731

unsigned int if_index = if_nametoindex(interface);

1732

if(if_index == 0){

1733

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

1734

errno = old_errno;

1735

return ENXIO;

1736

}

1737

if(interface_is_up(interface)){

1738

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

1739

ret_errno = errno;

1740

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

1741

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

1742

return ret_errno;

1743

}

1744

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

1745

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

1748

ret_errno = errno;

1749

perror_plus("socket");

1750

errno = old_errno;

1751

return ret_errno;

1752

}

1753

1754

if(debug){

1755

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

1756

interface);

1757

}

1758

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

1767

1768

/* Close the socket */

1769

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

1770

if(ret == -1){

1771

perror_plus("close");

1772

}

1773

1774

if(ret_setflags == -1){

1775

errno = ret_errno;

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1777

errno = old_errno;

1778

return ret_errno;

1779

}

1780

} else if(debug){

1781

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

1782

interface);

1783

}

1784

1785

errno = old_errno;

1786

return 0;

1787

}

1788

1235

1789

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

1790

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

1791

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

1792

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

1793

.interfaces = NULL, .interfaces_size = 0 };

1236

1794

AvahiSServiceBrowser *sb = NULL;

1237

int error;

1795

error_t ret_errno;

1238

1796

int ret;

1239

1797

intmax_t tmpmax;

1240

1798

char *tmp;

1241

1799

int exitcode = EXIT_SUCCESS;

1242

const char *interface = "";

1243

struct ifreq network;

1244

int sd = -1;

1245

bool take_down_interface = false;

1246

uid_t uid;

1247

gid_t gid;

1800

char *interfaces_to_take_down = NULL;

1801

size_t interfaces_to_take_down_size = 0;

1248

1802

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

1249

1803

bool tempdir_created = false;

1250

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1251

1805

const char *seckey = PATHDIR "/" SECKEY;

1252

1806

const char *pubkey = PATHDIR "/" PUBKEY;

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1253

1809

1254

1810

bool gnutls_initialized = false;

1255

1811

bool gpgme_initialized = false;

1317

1873

.group = 2 },

1318

1874

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

1319

1875

.arg = "SECONDS",

1320

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

1876

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

1877

.group = 2 },

1878

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

1879

.arg = "DIR",

1880

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

1321

1881

.group = 2 },

1322

1882

/*

1323

1883

* These reproduce what we would get without ARGP_NO_HELP

1342

1902

connect_to = arg;

1343

1903

break;

1344

1904

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

1345

interface = arg;

1905

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

1906

arg, (int)',');

1907

if(ret_errno != 0){

1908

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

1909

}

1346

1910

break;

1347

1911

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

1348

1912

seckey = arg;

1377

1941

argp_error(state, "Bad retry interval");

1378

1942

}

1379

1943

break;

1944

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

1945

hookdir = arg;

1946

break;

1380

1947

/*

1381

1948

* These reproduce what we would get without ARGP_NO_HELP

1382

1949

*/

1388

1955

argp_state_help(state, state->out_stream,

1389

1956

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1390

1957

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

1391

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

1958

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

1392

1959

exit(argp_err_exit_status);

1393

1960

break;

1394

1961

default:

1421

1988

{

1422

1989

/* Work around Debian bug #633582:

1423

1990

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

1424

struct stat st;

1425

1991

1426

1992

/* Re-raise priviliges */

1427

errno = 0;

1428

ret = seteuid(0);

1429

if(ret == -1){

1430

perror_plus("seteuid");

1431

}

1432

1433

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

1434

int seckey_fd = open(seckey, O_RDONLY);

1435

if(seckey_fd == -1){

1436

perror_plus("open");

1437

} else {

1438

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

1439

if(ret == -1){

1440

perror_plus("fstat");

1441

} else {

1442

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

1443

ret = fchown(seckey_fd, uid, gid);

1444

if(ret == -1){

1445

perror_plus("fchown");

1446

}

1447

}

1448

}

1449

TEMP_FAILURE_RETRY(close(seckey_fd));

1450

}

1451

}

1452

1453

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

1454

int pubkey_fd = open(pubkey, O_RDONLY);

1455

if(pubkey_fd == -1){

1456

perror_plus("open");

1457

} else {

1458

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

1459

if(ret == -1){

1460

perror_plus("fstat");

1461

} else {

1462

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

1463

ret = fchown(pubkey_fd, uid, gid);

1464

if(ret == -1){

1465

perror_plus("fchown");

1466

}

1467

}

1468

}

1469

TEMP_FAILURE_RETRY(close(pubkey_fd));

1470

}

1471

}

1472

1473

/* Lower privileges */

1474

errno = 0;

1475

ret = seteuid(uid);

1476

if(ret == -1){

1477

perror_plus("seteuid");

1993

if(raise_privileges() == 0){

1994

struct stat st;

1995

1996

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

1997

int seckey_fd = open(seckey, O_RDONLY);

1998

if(seckey_fd == -1){

1999

perror_plus("open");

2000

} else {

2001

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

2002

if(ret == -1){

2003

perror_plus("fstat");

2004

} else {

2005

if(S_ISREG(st.st_mode)

2006

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

2007

ret = fchown(seckey_fd, uid, gid);

2008

if(ret == -1){

2009

perror_plus("fchown");

2010

}

2011

}

2012

}

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2014

}

2015

}

2016

2017

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

2018

int pubkey_fd = open(pubkey, O_RDONLY);

2019

if(pubkey_fd == -1){

2020

perror_plus("open");

2021

} else {

2022

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

2023

if(ret == -1){

2024

perror_plus("fstat");

2025

} else {

2026

if(S_ISREG(st.st_mode)

2027

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

2028

ret = fchown(pubkey_fd, uid, gid);

2029

if(ret == -1){

2030

perror_plus("fchown");

2031

}

2032

}

2033

}

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2038

/* Lower privileges */

2039

lower_privileges();

2040

}

2041

}

2042

2043

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

2044

{

2045

char *interface = NULL;

2046

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

2047

interface))){

2048

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

2049

and if_nametoindex(interface) == 0){

2050

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

2051

fprintf_plus(stderr, "Not using nonexisting interface"

2052

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

2053

}

2054

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

2055

interface = NULL;

2056

}

2057

}

2058

}

2059

2060

/* Run network hooks */

2061

{

2062

if(mc.interfaces != NULL){

2063

interfaces_hooks = malloc(mc.interfaces_size);

2064

if(interfaces_hooks == NULL){

2065

perror_plus("malloc");

2066

goto end;

2067

}

2068

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

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

2072

}

2073

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

2074

interfaces_hooks : "", delay)){

2075

goto end;

1478

2076

}

1479

2077

}

1480

2078

1481

2079

if(not debug){

1482

2080

avahi_set_log_function(empty_log);

1483

2081

}

1484

1485

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

1486

struct dirent **direntries;

1487

ret = scandir(sys_class_net, &direntries, good_interface,

1488

alphasort);

1489

if(ret >= 1){

1490

/* Pick the first good interface */

1491

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

1492

if(debug){

1493

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

1494

}

1495

if(interface == NULL){

1496

perror_plus("malloc");

1497

free(direntries);

1498

exitcode = EXIT_FAILURE;

1499

goto end;

1500

}

1501

free(direntries);

1502

} else {

1503

free(direntries);

1504

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

1505

exitcode = EXIT_FAILURE;

1506

goto end;

1507

}

1508

}

1509

2082

1510

2083

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

1511

2084

from the signal handler */

1512

2085

/* Initialize the pseudo-RNG for Avahi */

1513

2086

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

1514

mc.simple_poll = avahi_simple_poll_new();

1515

if(mc.simple_poll == NULL){

1516

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

2087

simple_poll = avahi_simple_poll_new();

2088

if(simple_poll == NULL){

2089

fprintf_plus(stderr,

2090

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

1517

2091

exitcode = EX_UNAVAILABLE;

1518

2092

goto end;

1519

2093

}

1581

2155

}

1582

2156

}

1583

2157

1584

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

1585

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

1586

if_index = (AvahiIfIndex) if_nametoindex(interface);

1587

if(if_index == 0){

1588

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

1589

exitcode = EX_UNAVAILABLE;

1590

goto end;

1591

}

1592

1593

if(quit_now){

1594

goto end;

1595

}

1596

1597

/* Re-raise priviliges */

1598

errno = 0;

1599

ret = seteuid(0);

1600

if(ret == -1){

1601

perror_plus("seteuid");

1602

}

1603

1604

#ifdef __linux__

1605

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1606

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

1607

ret = klogctl(8, NULL, 5);

1608

bool restore_loglevel = true;

1609

if(ret == -1){

1610

restore_loglevel = false;

1611

perror_plus("klogctl");

1612

}

1613

#endif /* __linux__ */

1614

1615

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1616

if(sd < 0){

1617

perror_plus("socket");

1618

exitcode = EX_OSERR;

1619

#ifdef __linux__

1620

if(restore_loglevel){

1621

ret = klogctl(7, NULL, 0);

1622

if(ret == -1){

1623

perror_plus("klogctl");

1624

}

1625

}

1626

#endif /* __linux__ */

1627

/* Lower privileges */

1628

errno = 0;

1629

ret = seteuid(uid);

1630

if(ret == -1){

1631

perror_plus("seteuid");

1632

}

1633

goto end;

1634

}

1635

strcpy(network.ifr_name, interface);

1636

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

1637

if(ret == -1){

1638

perror_plus("ioctl SIOCGIFFLAGS");

1639

#ifdef __linux__

1640

if(restore_loglevel){

1641

ret = klogctl(7, NULL, 0);

1642

if(ret == -1){

1643

perror_plus("klogctl");

1644

}

1645

}

1646

#endif /* __linux__ */

1647

exitcode = EX_OSERR;

1648

/* Lower privileges */

1649

errno = 0;

1650

ret = seteuid(uid);

1651

if(ret == -1){

1652

perror_plus("seteuid");

1653

}

1654

goto end;

1655

}

1656

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

1657

network.ifr_flags |= IFF_UP;

1658

take_down_interface = true;

1659

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

1660

if(ret == -1){

1661

take_down_interface = false;

1662

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1663

exitcode = EX_OSERR;

1664

#ifdef __linux__

1665

if(restore_loglevel){

1666

ret = klogctl(7, NULL, 0);

1667

if(ret == -1){

1668

perror_plus("klogctl");

2158

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

2159

if(mc.interfaces == NULL){

2160

struct dirent **direntries;

2161

/* Look for any good interfaces */

2162

ret = scandir(sys_class_net, &direntries, good_interface,

2163

alphasort);

2164

if(ret >= 1){

2165

/* Add all found interfaces to interfaces list */

2166

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

2167

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

2168

direntries[i]->d_name);

2169

if(ret_errno != 0){

2170

perror_plus("argz_add");

2171

continue;

2172

}

2173

if(debug){

2174

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

2175

direntries[i]->d_name);

2176

}

2177

}

2178

free(direntries);

2179

} else {

2180

free(direntries);

2181

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

2182

exitcode = EXIT_FAILURE;

2183

goto end;

2184

}

2185

}

2186

2187

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

2188

{

2189

char *interface = NULL;

2190

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

2191

interface))){

2192

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

2193

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

2194

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

2195

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

2196

interface);

2197

interface = NULL;

2198

while((interface = argz_next(mc.interfaces,

2199

mc.interfaces_size, interface))){

2200

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

2201

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

2202

interface);

2203

interface = NULL;

1669

2204

}

1670

2205

}

1671

#endif /* __linux__ */

1672

/* Lower privileges */

1673

errno = 0;

1674

ret = seteuid(uid);

1675

if(ret == -1){

1676

perror_plus("seteuid");

1677

}

1678

goto end;

1679

}

1680

}

1681

/* Sleep checking until interface is running.

1682

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

1683

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

1684

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

1685

if(ret == -1){

1686

perror_plus("ioctl SIOCGIFFLAGS");

1687

} else if(network.ifr_flags & IFF_RUNNING){

1688

2206

break;

1689

2207

}

1690

struct timespec sleeptime = { .tv_nsec = 250000000 };

1691

ret = nanosleep(&sleeptime, NULL);

1692

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

1693

perror_plus("nanosleep");

1694

}

1695

}

1696

if(not take_down_interface){

1697

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

1698

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

1699

if(ret == -1){

1700

perror_plus("close");

1701

}

1702

}

1703

#ifdef __linux__

1704

if(restore_loglevel){

1705

/* Restores kernel loglevel to default */

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

1709

}

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

if(take_down_interface){

1715

/* Lower privileges */

1716

ret = seteuid(uid);

1717

if(ret == -1){

1718

perror_plus("seteuid");

1719

}

1720

} else {

1721

/* Lower privileges permanently */

1722

ret = setuid(uid);

1723

if(ret == -1){

1724

perror_plus("setuid");

1725

}

1726

}

2208

bool interface_was_up = interface_is_up(interface);

2209

ret = bring_up_interface(interface, delay);

2210

if(not interface_was_up){

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2214

} else {

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2218

}

2219

}

2220

}

2221

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

2222

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

2223

}

2224

}

2225

2226

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

2227

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

2228

if(debug){

2229

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

2230

mc.interfaces);

2231

}

2232

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

1727

2233

}

1728

2234

1729

2235

if(quit_now){

1730

2236

goto end;

1731

2237

}

1732

2238

1733

ret = init_gnutls_global(pubkey, seckey);

2239

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

1734

2240

if(ret == -1){

1735

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

2241

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

1736

2242

exitcode = EX_UNAVAILABLE;

1737

2243

goto end;

1738

2244

} else {

1753

2259

goto end;

1754

2260

}

1755

2261

1756

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

1757

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

2262

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

2263

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

1758

2264

exitcode = EX_UNAVAILABLE;

1759

2265

goto end;

1760

2266

} else {

1769

2275

/* Connect directly, do not use Zeroconf */

1770

2276

/* (Mainly meant for debugging) */

1771

2277

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

2278

1772

2279

if(address == NULL){

1773

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

2280

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

1774

2281

exitcode = EX_USAGE;

1775

2282

goto end;

1776

2283

}

1779

2286

goto end;

1780

2287

}

1781

2288

1782

uint16_t port;

2289

in_port_t port;

1783

2290

errno = 0;

1784

2291

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

1785

2292

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

1786

or tmpmax != (uint16_t)tmpmax){

1787

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

2293

or tmpmax != (in_port_t)tmpmax){

2294

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

1788

2295

exitcode = EX_USAGE;

1789

2296

goto end;

1790

2297

}

1791

2298

1792

2299

if(quit_now){

1793

2300

goto end;

1794

2301

}

1795

2302

1796

port = (uint16_t)tmpmax;

2303

port = (in_port_t)tmpmax;

1797

2304

*address = '\0';

1798

2305

/* Colon in address indicates IPv6 */

1799

2306

int af;

1815

2322

}

1816

2323

1817

2324

while(not quit_now){

1818

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

2325

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

2326

&mc);

1819

2327

if(quit_now or ret == 0){

1820

2328

break;

1821

2329

}

1822

2330

if(debug){

1823

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

1824

(int)retry_interval);

2331

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

2332

(int)retry_interval);

1825

2333

}

1826

2334

sleep((int)retry_interval);

1827

2335

}

1829

2337

if (not quit_now){

1830

2338

exitcode = EXIT_SUCCESS;

1831

2339

}

1832

2340

1833

2341

goto end;

1834

2342

}

1835

2343

1847

2355

config.publish_domain = 0;

1848

2356

1849

2357

/* Allocate a new server */

1850

mc.server = avahi_server_new(avahi_simple_poll_get

1851

(mc.simple_poll), &config, NULL,

1852

NULL, &error);

2358

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2359

&config, NULL, NULL, &ret_errno);

1853

2360

1854

2361

/* Free the Avahi configuration data */

1855

2362

avahi_server_config_free(&config);

1857

2364

1858

2365

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

1859

2366

if(mc.server == NULL){

1860

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

1861

avahi_strerror(error));

2367

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

2368

avahi_strerror(ret_errno));

1862

2369

exitcode = EX_UNAVAILABLE;

1863

2370

goto end;

1864

2371

}

1870

2377

/* Create the Avahi service browser */

1871

2378

sb = avahi_s_service_browser_new(mc.server, if_index,

1872

2379

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1873

NULL, 0, browse_callback, NULL);

2380

NULL, 0, browse_callback,

2381

(void *)&mc);

1874

2382

if(sb == NULL){

1875

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

1876

avahi_strerror(avahi_server_errno(mc.server)));

2383

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

2384

avahi_strerror(avahi_server_errno(mc.server)));

1877

2385

exitcode = EX_UNAVAILABLE;

1878

2386

goto end;

1879

2387

}

1885

2393

/* Run the main loop */

1886

2394

1887

2395

if(debug){

1888

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

2396

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

1889

2397

}

1890

2398

1891

ret = avahi_loop_with_timeout(mc.simple_poll,

1892

(int)(retry_interval * 1000));

2399

ret = avahi_loop_with_timeout(simple_poll,

2400

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

1893

2401

if(debug){

1894

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

1895

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

2402

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

2403

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

1896

2404

}

1897

2405

1898

2406

end:

1899

2407

1900

2408

if(debug){

1901

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

2409

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

1902

2410

}

1903

2411

1904

2412

/* Cleanup things */

2413

free(mc.interfaces);

2414

1905

2415

if(sb != NULL)

1906

2416

avahi_s_service_browser_free(sb);

1907

2417

1908

2418

if(mc.server != NULL)

1909

2419

avahi_server_free(mc.server);

1910

2420

1911

if(mc.simple_poll != NULL)

1912

avahi_simple_poll_free(mc.simple_poll);

2421

if(simple_poll != NULL)

2422

avahi_simple_poll_free(simple_poll);

1913

2423

1914

2424

if(gnutls_initialized){

1915

2425

gnutls_certificate_free_credentials(mc.cred);

1920

2430

if(gpgme_initialized){

1921

2431

gpgme_release(mc.ctx);

1922

2432

}

1923

2433

1924

2434

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

1925

2435

has seen */

1926

2436

if(mc.current_server != NULL){

1932

2442

}

1933

2443

}

1934

2444

1935

/* Take down the network interface */

1936

if(take_down_interface){

1937

/* Re-raise priviliges */

1938

errno = 0;

1939

ret = seteuid(0);

1940

if(ret == -1){

1941

perror_plus("seteuid");

1942

}

1943

if(geteuid() == 0){

1944

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

1945

if(ret == -1){

1946

perror_plus("ioctl SIOCGIFFLAGS");

1947

} else if(network.ifr_flags & IFF_UP) {

1948

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

1949

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

1950

if(ret == -1){

1951

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2445

/* Re-raise priviliges */

2446

{

2447

raise_privileges();

2448

2449

/* Run network hooks */

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2452

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

1952

2463

}

1953

2464

}

1954

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

1955

if(ret == -1){

1956

perror_plus("close");

1957

}

1958

/* Lower privileges permanently */

1959

errno = 0;

1960

ret = setuid(uid);

1961

if(ret == -1){

1962

perror_plus("setuid");

2465

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

2466

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

2467

" down\n");

1963

2468

}

1964

2469

}

2470

2471

lower_privileges_permanently();

1965

2472

}

1966

2473

2474

free(interfaces_to_take_down);

2475

free(interfaces_hooks);

2476

1967

2477

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

1968

2478

if(tempdir_created){

1969

2479

struct dirent **direntries = NULL;

1982

2492

}

1983

2493

ret = remove(fullname);

1984

2494

if(ret == -1){

1985

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

1986

strerror(errno));

2495

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

2496

strerror(errno));

1987

2497

}

1988

2498

free(fullname);

1989

2499

}