/mandos/trunk : revision 609

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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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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,

341

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0);

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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",

364

gpgme_strsource(rc), gpgme_strerror(rc));

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return -1;

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366

}

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348

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

349

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rc = gpgme_data_new(&dh_plain);

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370

if(rc != GPG_ERR_NO_ERROR){

351

fprintf(stderr, "bad gpgme_data_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: "

372

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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374

gpgme_data_release(dh_crypto);

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375

return -1;

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376

}

356

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357

378

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

358

379

data buffer */

359

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

380

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

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381

if(rc != GPG_ERR_NO_ERROR){

361

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

362

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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plaintext_length = -1;

364

385

if(debug){

365

386

gpgme_decrypt_result_t result;

366

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

367

388

if(result == NULL){

368

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

389

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

369

390

} else {

370

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

371

result->unsupported_algorithm);

372

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

373

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);

374

395

if(result->file_name != NULL){

375

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

396

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

376

397

}

377

398

gpgme_recipient_t recipient;

378

399

recipient = result->recipients;

379

400

while(recipient != NULL){

380

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

381

gpgme_pubkey_algo_name(recipient->pubkey_algo));

382

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

383

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

384

recipient->status == GPG_ERR_NO_SECKEY

385

? "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");

386

408

recipient = recipient->next;

387

409

}

388

410

}

391

413

}

392

414

393

415

if(debug){

394

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

416

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

395

417

}

396

418

397

419

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

404

426

*plaintext = NULL;

405

427

while(true){

406

428

plaintext_capacity = incbuffer(plaintext,

407

(size_t)plaintext_length,

408

plaintext_capacity);

429

(size_t)plaintext_length,

430

plaintext_capacity);

409

431

if(plaintext_capacity == 0){

410

perror_plus("incbuffer");

411

plaintext_length = -1;

412

goto decrypt_end;

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

413

435

}

414

436

415

437

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

428

450

}

429

451

430

452

if(debug){

431

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

453

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

432

454

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

433

455

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

434

456

}

446

468

}

447

469

448

470

static const char * safer_gnutls_strerror(int value){

449

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

450

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

451

472

if(ret == NULL)

452

473

ret = "(unknown)";

453

474

return ret;

456

477

/* GnuTLS log function callback */

457

478

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

458

479

const char* string){

459

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

480

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

460

481

}

461

482

462

483

static int init_gnutls_global(const char *pubkeyfilename,

463

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

464

486

int ret;

465

487

466

488

if(debug){

467

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

489

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

468

490

}

469

491

470

492

ret = gnutls_global_init();

471

493

if(ret != GNUTLS_E_SUCCESS){

472

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

473

safer_gnutls_strerror(ret));

494

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

495

safer_gnutls_strerror(ret));

474

496

return -1;

475

497

}

476

498

483

505

}

484

506

485

507

/* OpenPGP credentials */

486

ret = gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

487

509

if(ret != GNUTLS_E_SUCCESS){

488

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

489

safer_gnutls_strerror(ret));

510

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

511

safer_gnutls_strerror(ret));

490

512

gnutls_global_deinit();

491

513

return -1;

492

514

}

493

515

494

516

if(debug){

495

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

496

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

497

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);

498

521

}

499

522

500

523

ret = gnutls_certificate_set_openpgp_key_file

501

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

502

525

GNUTLS_OPENPGP_FMT_BASE64);

503

526

if(ret != GNUTLS_E_SUCCESS){

504

fprintf(stderr,

505

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

506

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

507

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

508

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));

509

532

goto globalfail;

510

533

}

511

534

512

535

/* GnuTLS server initialization */

513

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

514

537

if(ret != GNUTLS_E_SUCCESS){

515

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

516

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

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

517

541

goto globalfail;

518

542

}

519

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

543

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

520

544

if(ret != GNUTLS_E_SUCCESS){

521

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

522

safer_gnutls_strerror(ret));

545

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

546

safer_gnutls_strerror(ret));

523

547

goto globalfail;

524

548

}

525

549

526

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

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

527

551

528

552

return 0;

529

553

530

554

globalfail:

531

555

532

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

533

557

gnutls_global_deinit();

534

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

535

559

return -1;

536

560

}

537

561

538

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

539

564

int ret;

540

565

/* GnuTLS session creation */

541

566

do {

545

570

}

546

571

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

547

572

if(ret != GNUTLS_E_SUCCESS){

548

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

549

safer_gnutls_strerror(ret));

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

550

576

}

551

577

552

578

{

553

579

const char *err;

554

580

do {

555

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

581

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

556

582

if(quit_now){

557

583

gnutls_deinit(*session);

558

584

return -1;

559

585

}

560

586

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

561

587

if(ret != GNUTLS_E_SUCCESS){

562

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

563

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

564

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));

565

591

gnutls_deinit(*session);

566

592

return -1;

567

593

}

569

595

570

596

do {

571

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

572

mc.cred);

598

mc->cred);

573

599

if(quit_now){

574

600

gnutls_deinit(*session);

575

601

return -1;

576

602

}

577

603

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

578

604

if(ret != GNUTLS_E_SUCCESS){

579

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

580

safer_gnutls_strerror(ret));

605

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

606

safer_gnutls_strerror(ret));

581

607

gnutls_deinit(*session);

582

608

return -1;

583

609

}

585

611

/* ignore client certificate if any. */

586

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

587

613

588

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

589

615

590

616

return 0;

591

617

}

595

621

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

596

622

597

623

/* Called when a Mandos server is found */

598

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

624

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

599

625

AvahiIfIndex if_index,

600

int af){

626

int af, mandos_context *mc){

601

627

int ret, tcp_sd = -1;

602

628

ssize_t sret;

603

629

union {

628

654

pf = PF_INET;

629

655

break;

630

656

default:

631

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

657

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

632

658

errno = EINVAL;

633

659

return -1;

634

660

}

635

661

636

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);

637

695

if(ret != 0){

638

696

return -1;

639

697

}

640

698

641

699

if(debug){

642

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

643

"\n", ip, port);

700

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

701

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

644

702

}

645

703

646

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

672

730

}

673

731

if(ret == 0){

674

732

int e = errno;

675

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

733

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

676

734

errno = e;

677

735

goto mandos_end;

678

736

}

679

737

if(af == AF_INET6){

680

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

681

-Wconversion and

682

-Wunreachable-code */

683

738

to.in6.sin6_port = htons(port);

684

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

685

740

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

686

-Wunreachable-code*/

741

-Wunreachable-code*/

687

742

if(if_index == AVAHI_IF_UNSPEC){

688

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

689

" without a network interface\n");

743

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

744

" incomplete without a network interface\n");

690

745

errno = EINVAL;

691

746

goto mandos_end;

692

747

}

710

765

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

711

766

perror_plus("if_indextoname");

712

767

} else {

713

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

714

ip, interface, port);

768

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

769

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

715

770

}

716

771

} else {

717

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

718

port);

772

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

773

ip, (uintmax_t)port);

719

774

}

720

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

721

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

731

786

perror_plus("inet_ntop");

732

787

} else {

733

788

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

734

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

789

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

735

790

}

736

791

}

737

792

}

765

820

while(true){

766

821

size_t out_size = strlen(out);

767

822

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

768

out_size - written));

823

out_size - written));

769

824

if(ret == -1){

770

825

int e = errno;

771

826

perror_plus("write");

791

846

}

792

847

793

848

if(debug){

794

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

849

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

795

850

}

796

851

797

852

if(quit_now){

799

854

goto mandos_end;

800

855

}

801

856

802

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

803

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);

804

862

805

863

if(quit_now){

806

864

errno = EINTR;

817

875

818

876

if(ret != GNUTLS_E_SUCCESS){

819

877

if(debug){

820

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

878

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

821

879

gnutls_perror(ret);

822

880

}

823

881

errno = EPROTO;

827

885

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

828

886

829

887

if(debug){

830

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

831

ip);

888

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

889

" %s\n", ip);

832

890

}

833

891

834

892

while(true){

839

897

}

840

898

841

899

buffer_capacity = incbuffer(&buffer, buffer_length,

842

buffer_capacity);

900

buffer_capacity);

843

901

if(buffer_capacity == 0){

844

902

int e = errno;

845

903

perror_plus("incbuffer");

872

930

}

873

931

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

874

932

if(ret < 0){

875

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

933

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

934

"***\n");

876

935

gnutls_perror(ret);

877

936

errno = EPROTO;

878

937

goto mandos_end;

879

938

}

880

939

break;

881

940

default:

882

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

883

" encrypted session with Mandos server\n");

941

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

942

" encrypted session with Mandos server\n");

884

943

gnutls_bye(session, GNUTLS_SHUT_RDWR);

885

944

errno = EIO;

886

945

goto mandos_end;

891

950

}

892

951

893

952

if(debug){

894

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

953

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

895

954

}

896

955

897

956

if(quit_now){

909

968

910

969

if(buffer_length > 0){

911

970

ssize_t decrypted_buffer_size;

912

decrypted_buffer_size = pgp_packet_decrypt(buffer,

913

buffer_length,

914

&decrypted_buffer);

971

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

972

&decrypted_buffer, mc);

915

973

if(decrypted_buffer_size >= 0){

916

974

917

975

written = 0;

927

985

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

928

986

int e = errno;

929

987

if(debug){

930

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

931

strerror(errno));

988

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

989

strerror(errno));

932

990

}

933

991

errno = e;

934

992

goto mandos_end;

978

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

979

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

980

1038

flags,

981

AVAHI_GCC_UNUSED void* userdata){

982

assert(r);

1039

void* mc){

1040

if(r == NULL){

1041

return;

1042

}

983

1043

984

1044

/* Called whenever a service has been resolved successfully or

985

1045

timed out */

991

1051

switch(event){

992

1052

default:

993

1053

case AVAHI_RESOLVER_FAILURE:

994

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

995

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

996

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)));

997

1059

break;

998

1060

999

1061

case AVAHI_RESOLVER_FOUND:

1001

1063

char ip[AVAHI_ADDRESS_STR_MAX];

1002

1064

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

1003

1065

if(debug){

1004

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

1005

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

1006

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);

1007

1069

}

1008

int ret = start_mandos_communication(ip, port, interface,

1009

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);

1010

1074

if(ret == 0){

1011

avahi_simple_poll_quit(mc.simple_poll);

1075

avahi_simple_poll_quit(simple_poll);

1012

1076

} else {

1013

ret = add_server(ip, port, interface,

1014

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

}

1015

1083

}

1016

1084

}

1017

1085

}

1027

1095

const char *domain,

1028

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1029

1097

flags,

1030

AVAHI_GCC_UNUSED void* userdata){

1031

assert(b);

1098

void* mc){

1099

if(b == NULL){

1100

return;

1101

}

1032

1102

1033

1103

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

1034

1104

is removed from the LAN */

1041

1111

default:

1042

1112

case AVAHI_BROWSER_FAILURE:

1043

1113

1044

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

1045

avahi_strerror(avahi_server_errno(mc.server)));

1046

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);

1047

1118

return;

1048

1119

1049

1120

case AVAHI_BROWSER_NEW:

1052

1123

the callback function is called the Avahi server will free the

1053

1124

resolver for us. */

1054

1125

1055

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

1056

name, type, domain, protocol, 0,

1057

resolve_callback, NULL) == NULL)

1058

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

1059

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)));

1060

1134

break;

1061

1135

1062

1136

case AVAHI_BROWSER_REMOVE:

1065

1139

case AVAHI_BROWSER_ALL_FOR_NOW:

1066

1140

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1067

1141

if(debug){

1068

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

1142

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

1143

" searching...\n");

1069

1144

}

1070

1145

break;

1071

1146

}

1080

1155

signal_received = sig;

1081

1156

int old_errno = errno;

1082

1157

/* set main loop to exit */

1083

if(mc.simple_poll != NULL){

1084

avahi_simple_poll_quit(mc.simple_poll);

1158

if(simple_poll != NULL){

1159

avahi_simple_poll_quit(simple_poll);

1085

1160

}

1086

1161

errno = old_errno;

1087

1162

}

1088

1163

1089

1164

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

1090

1165

int ret;

1166

error_t ret_errno;

1091

1167

1092

1168

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

1093

1169

if(s < 0){

1170

ret_errno = errno;

1094

1171

perror_plus("socket");

1172

errno = ret_errno;

1095

1173

return false;

1096

1174

}

1097

1175

strcpy(ifr->ifr_name, ifname);

1098

1176

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1099

1177

if(ret == -1){

1100

1178

if(debug){

1179

ret_errno = errno;

1101

1180

perror_plus("ioctl SIOCGIFFLAGS");

1181

errno = ret_errno;

1102

1182

}

1103

1183

return false;

1104

1184

}

1110

1190

/* Reject the loopback device */

1111

1191

if(ifr->ifr_flags & IFF_LOOPBACK){

1112

1192

if(debug){

1113

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

1114

ifname);

1193

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

1194

ifname);

1115

1195

}

1116

1196

return false;

1117

1197

}

1118

1198

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

1119

1199

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

1120

1200

if(debug){

1121

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

1122

ifname);

1201

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

1202

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

1123

1203

}

1124

1204

return true;

1125

1205

}

1126

1206

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

1127

1207

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

1128

1208

if(debug){

1129

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

1130

ifname);

1209

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1210

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

1131

1211

}

1132

1212

return false;

1133

1213

}

1134

1214

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

1135

1215

if(ifr->ifr_flags & IFF_NOARP){

1136

1216

if(debug){

1137

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

1217

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

1218

ifname);

1138

1219

}

1139

1220

return false;

1140

1221

}

1141

1222

1142

1223

/* Accept this device */

1143

1224

if(debug){

1144

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

1225

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

1145

1226

}

1146

1227

return true;

1147

1228

}

1152

1233

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

1153

1234

*/

1154

1235

int good_interface(const struct dirent *if_entry){

1155

int ret;

1156

1236

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

1157

1237

return 0;

1158

1238

}

1239

1159

1240

struct ifreq ifr;

1160

1161

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

}

1162

1246

return 0;

1163

1247

}

1164

1248

1169

1253

}

1170

1254

1171

1255

/*

1172

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

1173

* corresponds to an acceptable network device which is up.

1174

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

1256

* This function determines if a network interface is up.

1175

1257

*/

1176

int up_interface(const struct dirent *if_entry){

1177

ssize_t ssret;

1178

char *flagname = NULL;

1179

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

1180

return 0;

1181

}

1182

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

1183

if_entry->d_name);

1184

if(ret < 0){

1185

perror_plus("asprintf");

1186

return 0;

1187

}

1188

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

1189

if(flags_fd == -1){

1190

perror_plus("open");

1191

free(flagname);

1192

return 0;

1193

}

1194

free(flagname);

1195

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

1196

/* read line from flags_fd */

1197

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

1198

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

1199

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

1200

if(flagstring == NULL){

1201

perror_plus("malloc");

1202

close(flags_fd);

1203

return 0;

1204

}

1205

while(to_read > 0){

1206

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

1207

(size_t)to_read));

1208

if(ssret == -1){

1209

perror_plus("read");

1210

free(flagstring);

1211

close(flags_fd);

1212

return 0;

1213

}

1214

to_read -= ssret;

1215

if(ssret == 0){

1216

break;

1217

}

1218

}

1219

close(flags_fd);

1220

intmax_t tmpmax;

1221

char *tmp;

1222

errno = 0;

1223

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

1224

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

1225

and not (isspace(*tmp)))

1226

or tmpmax != (ifreq_flags)tmpmax){

1227

if(debug){

1228

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

1229

flagstring, if_entry->d_name);

1230

}

1231

free(flagstring);

1232

return 0;

1233

}

1234

free(flagstring);

1235

ifreq_flags flags = (ifreq_flags)tmpmax;

1236

/* Reject the loopback device */

1237

if(flags & IFF_LOOPBACK){

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

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

}

1244

1270

1245

/* Reject down interfaces */

1246

if(not (flags & IFF_UP)){

1247

return 0;

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;

1248

1282

}

1249

1283

1250

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

1251

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

1252

if(debug){

1253

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

1254

if_entry->d_name);

1255

}

1256

return 1;

1257

}

1258

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

1259

if(not (flags & IFF_BROADCAST)){

1260

if(debug){

1261

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

1262

if_entry->d_name);

1263

}

1264

return 0;

1265

}

1266

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

1267

if(flags & IFF_NOARP){

1268

if(debug){

1269

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

1270

if_entry->d_name);

1271

}

1272

return 0;

1273

}

1274

/* Accept this device */

1275

if(debug){

1276

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

1277

if_entry->d_name);

1278

}

1279

return 1;

1284

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

1280

1285

}

1281

1286

1282

1287

int notdotentries(const struct dirent *direntry){

1293

1298

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

1294

1299

int runnable_hook(const struct dirent *direntry){

1295

1300

int ret;

1301

size_t sret;

1296

1302

struct stat st;

1297

1303

1298

1304

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

1300

1306

return 0;

1301

1307

}

1302

1308

1303

/* Save pointer to last character */

1304

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

1305

1306

if(*end == '~'){

1307

/* Backup name~ */

1308

return 0;

1309

}

1310

1311

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

1312

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

1313

/* Temporary #name# */

1314

return 0;

1315

}

1316

1317

/* XXX more rules here */

1318

1319

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

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);

1320

1330

if(ret == -1){

1321

1331

if(debug){

1322

perror_plus("Could not stat plugin");

1332

perror_plus("Could not stat hook");

1323

1333

}

1324

1334

return 0;

1325

1335

}

1326

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

1336

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

1327

1337

/* Not a regular file */

1338

if(debug){

1339

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

1340

direntry->d_name);

1341

}

1328

1342

return 0;

1329

1343

}

1330

1344

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

1331

1345

/* Not executable */

1346

if(debug){

1347

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

1348

direntry->d_name);

1349

}

1332

1350

return 0;

1333

1351

}

1352

if(debug){

1353

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

1354

direntry->d_name);

1355

}

1334

1356

return 1;

1335

1357

}

1336

1358

1337

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

mandos_context *mc){

1338

1361

int ret;

1339

1362

struct timespec now;

1340

1363

struct timespec waited_time;

1341

1364

intmax_t block_time;

1342

1365

1343

1366

while(true){

1344

if(mc.current_server == NULL){

1367

if(mc->current_server == NULL){

1345

1368

if (debug){

1346

fprintf(stderr,

1347

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

1369

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

1370

" No timeout!\n");

1348

1371

}

1349

1372

ret = avahi_simple_poll_iterate(s, -1);

1350

1373

} else {

1351

1374

if (debug){

1352

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

1353

" or wait\n");

1375

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

1376

" it, or wait\n");

1354

1377

}

1355

1378

/* the current time */

1356

1379

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1361

1384

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

1362

1385

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

1363

1386

waited_time.tv_sec = (now.tv_sec

1364

- mc.current_server->last_seen.tv_sec);

1387

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

1365

1388

waited_time.tv_nsec = (now.tv_nsec

1366

- mc.current_server->last_seen.tv_nsec);

1389

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

1367

1390

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

1368

1391

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

1369

1392

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

1372

1395

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

1373

1396

1374

1397

if (debug){

1375

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

1398

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

1399

block_time);

1376

1400

}

1377

1401

1378

1402

if(block_time <= 0){

1379

ret = start_mandos_communication(mc.current_server->ip,

1380

mc.current_server->port,

1381

mc.current_server->if_index,

1382

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);

1383

1407

if(ret == 0){

1384

avahi_simple_poll_quit(mc.simple_poll);

1408

avahi_simple_poll_quit(s);

1385

1409

return 0;

1386

1410

}

1387

1411

ret = clock_gettime(CLOCK_MONOTONIC,

1388

&mc.current_server->last_seen);

1412

&mc->current_server->last_seen);

1389

1413

if(ret == -1){

1390

1414

perror_plus("clock_gettime");

1391

1415

return -1;

1392

1416

}

1393

mc.current_server = mc.current_server->next;

1417

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

1394

1418

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

1395

1419

servers, but don't block */

1396

1420

}

1398

1422

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

1399

1423

}

1400

1424

if(ret != 0){

1401

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

1425

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

1402

1426

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

1403

1427

}

1404

1428

}

1405

1429

}

1406

1430

}

1407

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

1408

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 };

1409

1794

AvahiSServiceBrowser *sb = NULL;

1410

int error;

1795

error_t ret_errno;

1411

1796

int ret;

1412

1797

intmax_t tmpmax;

1413

1798

char *tmp;

1414

1799

int exitcode = EXIT_SUCCESS;

1415

const char *interface = "";

1416

struct ifreq network;

1417

int sd = -1;

1418

bool take_down_interface = false;

1419

uid_t uid;

1420

gid_t gid;

1800

char *interfaces_to_take_down = NULL;

1801

size_t interfaces_to_take_down_size = 0;

1421

1802

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

1422

1803

bool tempdir_created = false;

1423

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1424

1805

const char *seckey = PATHDIR "/" SECKEY;

1425

1806

const char *pubkey = PATHDIR "/" PUBKEY;

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1426

1809

1427

1810

bool gnutls_initialized = false;

1428

1811

bool gpgme_initialized = false;

1490

1873

.group = 2 },

1491

1874

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

1492

1875

.arg = "SECONDS",

1493

.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",

1494

1881

.group = 2 },

1495

1882

/*

1496

1883

* These reproduce what we would get without ARGP_NO_HELP

1515

1902

connect_to = arg;

1516

1903

break;

1517

1904

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

1518

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

}

1519

1910

break;

1520

1911

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

1521

1912

seckey = arg;

1550

1941

argp_error(state, "Bad retry interval");

1551

1942

}

1552

1943

break;

1944

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

1945

hookdir = arg;

1946

break;

1553

1947

/*

1554

1948

* These reproduce what we would get without ARGP_NO_HELP

1555

1949

*/

1561

1955

argp_state_help(state, state->out_stream,

1562

1956

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1563

1957

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

1564

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

1958

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

1565

1959

exit(argp_err_exit_status);

1566

1960

break;

1567

1961

default:

1594

1988

{

1595

1989

/* Work around Debian bug #633582:

1596

1990

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

1597

struct stat st;

1598

1991

1599

1992

/* Re-raise priviliges */

1600

errno = 0;

1601

ret = seteuid(0);

1602

if(ret == -1){

1603

perror_plus("seteuid");

1604

}

1605

1606

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

1607

int seckey_fd = open(seckey, O_RDONLY);

1608

if(seckey_fd == -1){

1609

perror_plus("open");

1610

} else {

1611

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

1612

if(ret == -1){

1613

perror_plus("fstat");

1614

} else {

1615

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

1616

ret = fchown(seckey_fd, uid, gid);

1617

if(ret == -1){

1618

perror_plus("fchown");

1619

}

1620

}

1621

}

1622

TEMP_FAILURE_RETRY(close(seckey_fd));

1623

}

1624

}

1625

1626

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

1627

int pubkey_fd = open(pubkey, O_RDONLY);

1628

if(pubkey_fd == -1){

1629

perror_plus("open");

1630

} else {

1631

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

1632

if(ret == -1){

1633

perror_plus("fstat");

1634

} else {

1635

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

1636

ret = fchown(pubkey_fd, uid, gid);

1637

if(ret == -1){

1638

perror_plus("fchown");

1639

}

1640

}

1641

}

1642

TEMP_FAILURE_RETRY(close(pubkey_fd));

1643

}

1644

}

1645

1646

/* Lower privileges */

1647

errno = 0;

1648

ret = seteuid(uid);

1649

if(ret == -1){

1650

perror_plus("seteuid");

1651

}

1652

}

1653

1654

/* Find network hooks and run them */

1655

{

1656

struct dirent **direntries;

1657

struct dirent *direntry;

1658

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

1659

alphasort);

1660

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

1661

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

1662

direntry = direntries[0];

1663

char *fullname = NULL;

1664

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

1665

direntry->d_name);

1666

if(ret < 0){

1667

perror_plus("asprintf");

1668

continue;

1669

}

1670

pid_t hook_pid = fork();

1671

if(hook_pid == 0){

1672

/* Child */

1673

dup2(devnull, STDIN_FILENO);

1674

close(devnull);

1675

dup2(STDERR_FILENO, STDOUT_FILENO);

1676

setenv("DEVICE", interface, 1);

1677

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

1678

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

1679

/* setenv( XXX more here */

1680

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

1681

perror_plus("execl");

1682

}

1683

free(fullname);

1684

if(quit_now){

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");

1685

2066

goto end;

1686

2067

}

1687

}

1688

close(devnull);

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;

2076

}

1689

2077

}

1690

2078

1691

2079

if(not debug){

1692

2080

avahi_set_log_function(empty_log);

1693

2081

}

1694

2082

1695

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

1696

struct dirent **direntries;

1697

ret = scandir(sys_class_net, &direntries, good_interface,

1698

alphasort);

1699

if(ret >= 1){

1700

/* Pick the first good interface */

1701

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

1702

if(debug){

1703

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

1704

}

1705

if(interface == NULL){

1706

perror_plus("malloc");

1707

free(direntries);

1708

exitcode = EXIT_FAILURE;

1709

goto end;

1710

}

1711

free(direntries);

1712

} else {

1713

free(direntries);

1714

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

1715

exitcode = EXIT_FAILURE;

1716

goto end;

1717

}

1718

}

1719

1720

2083

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

1721

2084

from the signal handler */

1722

2085

/* Initialize the pseudo-RNG for Avahi */

1723

2086

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

1724

mc.simple_poll = avahi_simple_poll_new();

1725

if(mc.simple_poll == NULL){

1726

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");

1727

2091

exitcode = EX_UNAVAILABLE;

1728

2092

goto end;

1729

2093

}

1791

2155

}

1792

2156

}

1793

2157

1794

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

1795

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

1796

if_index = (AvahiIfIndex) if_nametoindex(interface);

1797

if(if_index == 0){

1798

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

1799

exitcode = EX_UNAVAILABLE;

1800

goto end;

1801

}

1802

1803

if(quit_now){

1804

goto end;

1805

}

1806

1807

/* Re-raise priviliges */

1808

errno = 0;

1809

ret = seteuid(0);

1810

if(ret == -1){

1811

perror_plus("seteuid");

1812

}

1813

1814

#ifdef __linux__

1815

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1816

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

1817

ret = klogctl(8, NULL, 5);

1818

bool restore_loglevel = true;

1819

if(ret == -1){

1820

restore_loglevel = false;

1821

perror_plus("klogctl");

1822

}

1823

#endif /* __linux__ */

1824

1825

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1826

if(sd < 0){

1827

perror_plus("socket");

1828

exitcode = EX_OSERR;

1829

#ifdef __linux__

1830

if(restore_loglevel){

1831

ret = klogctl(7, NULL, 0);

1832

if(ret == -1){

1833

perror_plus("klogctl");

1834

}

1835

}

1836

#endif /* __linux__ */

1837

/* Lower privileges */

1838

errno = 0;

1839

ret = seteuid(uid);

1840

if(ret == -1){

1841

perror_plus("seteuid");

1842

}

1843

goto end;

1844

}

1845

strcpy(network.ifr_name, interface);

1846

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

1847

if(ret == -1){

1848

perror_plus("ioctl SIOCGIFFLAGS");

1849

#ifdef __linux__

1850

if(restore_loglevel){

1851

ret = klogctl(7, NULL, 0);

1852

if(ret == -1){

1853

perror_plus("klogctl");

1854

}

1855

}

1856

#endif /* __linux__ */

1857

exitcode = EX_OSERR;

1858

/* Lower privileges */

1859

errno = 0;

1860

ret = seteuid(uid);

1861

if(ret == -1){

1862

perror_plus("seteuid");

1863

}

1864

goto end;

1865

}

1866

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

1867

network.ifr_flags |= IFF_UP;

1868

take_down_interface = true;

1869

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

1870

if(ret == -1){

1871

take_down_interface = false;

1872

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1873

exitcode = EX_OSERR;

1874

#ifdef __linux__

1875

if(restore_loglevel){

1876

ret = klogctl(7, NULL, 0);

1877

if(ret == -1){

1878

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;

1879

2204

}

1880

2205

}

1881

#endif /* __linux__ */

1882

/* Lower privileges */

1883

errno = 0;

1884

ret = seteuid(uid);

1885

if(ret == -1){

1886

perror_plus("seteuid");

1887

}

1888

goto end;

1889

}

1890

}

1891

/* Sleep checking until interface is running.

1892

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

1893

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

1894

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

1895

if(ret == -1){

1896

perror_plus("ioctl SIOCGIFFLAGS");

1897

} else if(network.ifr_flags & IFF_RUNNING){

1898

2206

break;

1899

2207

}

1900

struct timespec sleeptime = { .tv_nsec = 250000000 };

1901

ret = nanosleep(&sleeptime, NULL);

1902

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

1903

perror_plus("nanosleep");

1904

}

1905

}

1906

if(not take_down_interface){

1907

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

1908

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

1909

if(ret == -1){

1910

perror_plus("close");

1911

}

1912

}

1913

#ifdef __linux__

1914

if(restore_loglevel){

1915

/* Restores kernel loglevel to default */

1916

ret = klogctl(7, NULL, 0);

1917

if(ret == -1){

1918

perror_plus("klogctl");

1919

}

1920

}

1921

#endif /* __linux__ */

1922

/* Lower privileges */

1923

errno = 0;

1924

if(take_down_interface){

1925

/* Lower privileges */

1926

ret = seteuid(uid);

1927

if(ret == -1){

1928

perror_plus("seteuid");

1929

}

1930

} else {

1931

/* Lower privileges permanently */

1932

ret = setuid(uid);

1933

if(ret == -1){

1934

perror_plus("setuid");

1935

}

1936

}

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);

1937

2233

}

1938

2234

1939

2235

if(quit_now){

1940

2236

goto end;

1941

2237

}

1942

2238

1943

ret = init_gnutls_global(pubkey, seckey);

2239

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

1944

2240

if(ret == -1){

1945

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

2241

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

1946

2242

exitcode = EX_UNAVAILABLE;

1947

2243

goto end;

1948

2244

} else {

1963

2259

goto end;

1964

2260

}

1965

2261

1966

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

1967

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

2262

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

2263

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

1968

2264

exitcode = EX_UNAVAILABLE;

1969

2265

goto end;

1970

2266

} else {

1979

2275

/* Connect directly, do not use Zeroconf */

1980

2276

/* (Mainly meant for debugging) */

1981

2277

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

2278

1982

2279

if(address == NULL){

1983

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

2280

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

1984

2281

exitcode = EX_USAGE;

1985

2282

goto end;

1986

2283

}

1989

2286

goto end;

1990

2287

}

1991

2288

1992

uint16_t port;

2289

in_port_t port;

1993

2290

errno = 0;

1994

2291

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

1995

2292

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

1996

or tmpmax != (uint16_t)tmpmax){

1997

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

2293

or tmpmax != (in_port_t)tmpmax){

2294

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

1998

2295

exitcode = EX_USAGE;

1999

2296

goto end;

2000

2297

}

2001

2298

2002

2299

if(quit_now){

2003

2300

goto end;

2004

2301

}

2005

2302

2006

port = (uint16_t)tmpmax;

2303

port = (in_port_t)tmpmax;

2007

2304

*address = '\0';

2008

2305

/* Colon in address indicates IPv6 */

2009

2306

int af;

2025

2322

}

2026

2323

2027

2324

while(not quit_now){

2028

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

2325

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

2326

&mc);

2029

2327

if(quit_now or ret == 0){

2030

2328

break;

2031

2329

}

2032

2330

if(debug){

2033

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

2034

(int)retry_interval);

2331

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

2332

(int)retry_interval);

2035

2333

}

2036

2334

sleep((int)retry_interval);

2037

2335

}

2057

2355

config.publish_domain = 0;

2058

2356

2059

2357

/* Allocate a new server */

2060

mc.server = avahi_server_new(avahi_simple_poll_get

2061

(mc.simple_poll), &config, NULL,

2062

NULL, &error);

2358

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2359

&config, NULL, NULL, &ret_errno);

2063

2360

2064

2361

/* Free the Avahi configuration data */

2065

2362

avahi_server_config_free(&config);

2067

2364

2068

2365

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

2069

2366

if(mc.server == NULL){

2070

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

2071

avahi_strerror(error));

2367

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

2368

avahi_strerror(ret_errno));

2072

2369

exitcode = EX_UNAVAILABLE;

2073

2370

goto end;

2074

2371

}

2080

2377

/* Create the Avahi service browser */

2081

2378

sb = avahi_s_service_browser_new(mc.server, if_index,

2082

2379

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2083

NULL, 0, browse_callback, NULL);

2380

NULL, 0, browse_callback,

2381

(void *)&mc);

2084

2382

if(sb == NULL){

2085

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

2086

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)));

2087

2385

exitcode = EX_UNAVAILABLE;

2088

2386

goto end;

2089

2387

}

2095

2393

/* Run the main loop */

2096

2394

2097

2395

if(debug){

2098

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

2396

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

2099

2397

}

2100

2398

2101

ret = avahi_loop_with_timeout(mc.simple_poll,

2102

(int)(retry_interval * 1000));

2399

ret = avahi_loop_with_timeout(simple_poll,

2400

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

2103

2401

if(debug){

2104

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

2105

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

2402

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

2403

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

2106

2404

}

2107

2405

2108

2406

end:

2109

2407

2110

2408

if(debug){

2111

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

2409

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

2112

2410

}

2113

2411

2114

2412

/* Cleanup things */

2413

free(mc.interfaces);

2414

2115

2415

if(sb != NULL)

2116

2416

avahi_s_service_browser_free(sb);

2117

2417

2118

2418

if(mc.server != NULL)

2119

2419

avahi_server_free(mc.server);

2120

2420

2121

if(mc.simple_poll != NULL)

2122

avahi_simple_poll_free(mc.simple_poll);

2421

if(simple_poll != NULL)

2422

avahi_simple_poll_free(simple_poll);

2123

2423

2124

2424

if(gnutls_initialized){

2125

2425

gnutls_certificate_free_credentials(mc.cred);

2130

2430

if(gpgme_initialized){

2131

2431

gpgme_release(mc.ctx);

2132

2432

}

2133

2433

2134

2434

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

2135

2435

has seen */

2136

2436

if(mc.current_server != NULL){

2142

2442

}

2143

2443

}

2144

2444

2145

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

2146

2147

/* Take down the network interface */

2148

if(take_down_interface){

2149

/* Re-raise priviliges */

2150

errno = 0;

2151

ret = seteuid(0);

2152

if(ret == -1){

2153

perror_plus("seteuid");

2154

}

2155

if(geteuid() == 0){

2156

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

2157

if(ret == -1){

2158

perror_plus("ioctl SIOCGIFFLAGS");

2159

} else if(network.ifr_flags & IFF_UP) {

2160

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

2161

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

2162

if(ret == -1){

2163

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");

2164

2463

}

2165

2464

}

2166

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

2167

if(ret == -1){

2168

perror_plus("close");

2169

}

2170

/* Lower privileges permanently */

2171

errno = 0;

2172

ret = setuid(uid);

2173

if(ret == -1){

2174

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");

2175

2468

}

2176

2469

}

2470

2471

lower_privileges_permanently();

2177

2472

}

2178

2473

2474

free(interfaces_to_take_down);

2475

free(interfaces_hooks);

2476

2179

2477

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

2180

2478

if(tempdir_created){

2181

2479

struct dirent **direntries = NULL;

2194

2492

}

2195

2493

ret = remove(fullname);

2196

2494

if(ret == -1){

2197

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

2198

strerror(errno));

2495

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

2496

strerror(errno));

2199

2497

}

2200

2498

free(fullname);

2201

2499

}