/mandos/trunk : revision 500

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

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*

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* Everything else is

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*

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* This program is free software: you can redistribute it and/or

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* modify it under the terms of the GNU General Public License as

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* along with this program. If not, see

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

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*

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

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

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*/

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

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

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stdout, ferror(), remove() */

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

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

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#include <stddef.h> /* NULL, size_t, ssize_t */

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#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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*/

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

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strtoimax() */

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

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

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program_invocation_short_name */

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

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*/

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

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

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

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setgid(), pause() */

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

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

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

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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

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init_gnutls_session(),

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GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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server *current_server;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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return 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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182

if(buffer == NULL){

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188

}

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

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

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int af, server **current_server){

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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int ret;

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

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if(new_server == NULL){

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197

perror_plus("malloc");

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return false;

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return -1;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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return false;

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return -1;

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207

}

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/* Special case of first server */

226

if(*current_server == NULL){

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if (mc.current_server == NULL){

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210

new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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

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} else {

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new_server->next = *current_server;

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

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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mc.current_server->prev = new_server;

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}

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

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return false;

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return -1;

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}

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return true;

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return 0;

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226

}

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/*

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* Initialize GPGME.

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*/

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

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const char *tempdir, mandos_context *mc){

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

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

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239

*/

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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rc = gpgme_op_import(mc->ctx, pgp_data);

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rc = gpgme_op_import(mc.ctx, pgp_data);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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}

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if(debug){

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

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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

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rc = gpgme_get_engine_info(&engine_info);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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while(engine_info != NULL){

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engine_info = engine_info->next;

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}

317

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if(engine_info == NULL){

318

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

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tempdir);

302

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

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return false;

321

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}

322

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/* Create new GPGME "context" */

324

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

307

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

325

308

if(rc != GPG_ERR_NO_ERROR){

326

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

327

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

328

gpgme_strerror(rc));

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

329

311

return false;

330

312

}

331

313

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324

*/

343

325

static ssize_t pgp_packet_decrypt(const char *cryptotext,

344

326

size_t crypto_size,

345

char **plaintext,

346

mandos_context *mc){

327

char **plaintext){

347

328

gpgme_data_t dh_crypto, dh_plain;

348

329

gpgme_error_t rc;

349

330

ssize_t ret;

351

332

ssize_t plaintext_length = 0;

352

333

353

334

if(debug){

354

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

335

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

355

336

}

356

337

357

338

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

358

339

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

359

340

0);

360

341

if(rc != GPG_ERR_NO_ERROR){

361

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

362

gpgme_strsource(rc), gpgme_strerror(rc));

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

363

344

return -1;

364

345

}

365

346

366

347

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

367

348

rc = gpgme_data_new(&dh_plain);

368

349

if(rc != GPG_ERR_NO_ERROR){

369

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

370

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

371

gpgme_strsource(rc), gpgme_strerror(rc));

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

372

352

gpgme_data_release(dh_crypto);

373

353

return -1;

374

354

}

375

355

376

356

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

377

357

data buffer */

378

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

358

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

379

359

if(rc != GPG_ERR_NO_ERROR){

380

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

381

gpgme_strsource(rc), gpgme_strerror(rc));

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

382

362

plaintext_length = -1;

383

363

if(debug){

384

364

gpgme_decrypt_result_t result;

385

result = gpgme_op_decrypt_result(mc->ctx);

365

result = gpgme_op_decrypt_result(mc.ctx);

386

366

if(result == NULL){

387

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

367

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

388

368

} else {

389

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

390

result->unsupported_algorithm);

391

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

392

result->wrong_key_usage);

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

393

373

if(result->file_name != NULL){

394

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

374

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

395

375

}

396

376

gpgme_recipient_t recipient;

397

377

recipient = result->recipients;

398

378

while(recipient != NULL){

399

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

400

gpgme_pubkey_algo_name

401

(recipient->pubkey_algo));

402

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

403

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

404

recipient->status == GPG_ERR_NO_SECKEY

405

? "No" : "Yes");

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

406

385

recipient = recipient->next;

407

386

}

408

387

}

411

390

}

412

391

413

392

if(debug){

414

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

393

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

415

394

}

416

395

417

396

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

424

403

*plaintext = NULL;

425

404

while(true){

426

405

plaintext_capacity = incbuffer(plaintext,

427

(size_t)plaintext_length,

428

plaintext_capacity);

406

(size_t)plaintext_length,

407

plaintext_capacity);

429

408

if(plaintext_capacity == 0){

430

perror_plus("incbuffer");

431

plaintext_length = -1;

432

goto decrypt_end;

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

433

412

}

434

413

435

414

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

448

427

}

449

428

450

429

if(debug){

451

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

430

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

452

431

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

453

432

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

454

433

}

466

445

}

467

446

468

447

static const char * safer_gnutls_strerror(int value){

469

const char *ret = gnutls_strerror(value);

448

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

449

-Wunreachable-code */

470

450

if(ret == NULL)

471

451

ret = "(unknown)";

472

452

return ret;

475

455

/* GnuTLS log function callback */

476

456

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

477

457

const char* string){

478

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

458

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

479

459

}

480

460

481

461

static int init_gnutls_global(const char *pubkeyfilename,

482

const char *seckeyfilename,

483

mandos_context *mc){

462

const char *seckeyfilename){

484

463

int ret;

485

464

486

465

if(debug){

487

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

466

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

488

467

}

489

468

490

469

ret = gnutls_global_init();

491

470

if(ret != GNUTLS_E_SUCCESS){

492

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

493

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

494

473

return -1;

495

474

}

496

475

503

482

}

504

483

505

484

/* OpenPGP credentials */

506

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

507

486

if(ret != GNUTLS_E_SUCCESS){

508

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

509

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

510

489

gnutls_global_deinit();

511

490

return -1;

512

491

}

513

492

514

493

if(debug){

515

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

516

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

517

pubkeyfilename,

518

seckeyfilename);

494

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

495

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

496

seckeyfilename);

519

497

}

520

498

521

499

ret = gnutls_certificate_set_openpgp_key_file

522

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

523

501

GNUTLS_OPENPGP_FMT_BASE64);

524

502

if(ret != GNUTLS_E_SUCCESS){

525

fprintf_plus(stderr,

526

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

527

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

528

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

529

safer_gnutls_strerror(ret));

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

530

508

goto globalfail;

531

509

}

532

510

533

511

/* GnuTLS server initialization */

534

ret = gnutls_dh_params_init(&mc->dh_params);

512

ret = gnutls_dh_params_init(&mc.dh_params);

535

513

if(ret != GNUTLS_E_SUCCESS){

536

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

537

" initialization: %s\n",

538

safer_gnutls_strerror(ret));

514

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

515

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

539

516

goto globalfail;

540

517

}

541

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

518

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

542

519

if(ret != GNUTLS_E_SUCCESS){

543

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

544

safer_gnutls_strerror(ret));

520

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

521

safer_gnutls_strerror(ret));

545

522

goto globalfail;

546

523

}

547

524

548

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

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

549

526

550

527

return 0;

551

528

552

529

globalfail:

553

530

554

gnutls_certificate_free_credentials(mc->cred);

531

gnutls_certificate_free_credentials(mc.cred);

555

532

gnutls_global_deinit();

556

gnutls_dh_params_deinit(mc->dh_params);

533

gnutls_dh_params_deinit(mc.dh_params);

557

534

return -1;

558

535

}

559

536

560

static int init_gnutls_session(gnutls_session_t *session,

561

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

562

538

int ret;

563

539

/* GnuTLS session creation */

564

540

do {

568

544

}

569

545

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

570

546

if(ret != GNUTLS_E_SUCCESS){

571

fprintf_plus(stderr,

572

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

573

safer_gnutls_strerror(ret));

547

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

548

safer_gnutls_strerror(ret));

574

549

}

575

550

576

551

{

577

552

const char *err;

578

553

do {

579

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

554

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

580

555

if(quit_now){

581

556

gnutls_deinit(*session);

582

557

return -1;

583

558

}

584

559

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

585

560

if(ret != GNUTLS_E_SUCCESS){

586

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

587

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

588

safer_gnutls_strerror(ret));

561

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

562

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

563

safer_gnutls_strerror(ret));

589

564

gnutls_deinit(*session);

590

565

return -1;

591

566

}

593

568

594

569

do {

595

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc->cred);

571

mc.cred);

597

572

if(quit_now){

598

573

gnutls_deinit(*session);

599

574

return -1;

600

575

}

601

576

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

602

577

if(ret != GNUTLS_E_SUCCESS){

603

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

604

safer_gnutls_strerror(ret));

578

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

579

safer_gnutls_strerror(ret));

605

580

gnutls_deinit(*session);

606

581

return -1;

607

582

}

609

584

/* ignore client certificate if any. */

610

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

586

612

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

613

588

614

589

return 0;

615

590

}

619

594

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

620

595

621

596

/* Called when a Mandos server is found */

622

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

597

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

623

598

AvahiIfIndex if_index,

624

int af, mandos_context *mc){

599

int af){

625

600

int ret, tcp_sd = -1;

626

601

ssize_t sret;

627

602

union {

652

627

pf = PF_INET;

653

628

break;

654

629

default:

655

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

630

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

656

631

errno = EINVAL;

657

632

return -1;

658

633

}

659

634

660

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

661

636

if(ret != 0){

662

637

return -1;

663

638

}

664

639

665

640

if(debug){

666

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

667

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

641

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

642

"\n", ip, port);

668

643

}

669

644

670

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

696

671

}

697

672

if(ret == 0){

698

673

int e = errno;

699

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

674

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

700

675

errno = e;

701

676

goto mandos_end;

702

677

}

703

678

if(af == AF_INET6){

704

to.in6.sin6_port = htons(port);

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

705

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

706

684

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

707

-Wunreachable-code*/

685

-Wunreachable-code*/

708

686

if(if_index == AVAHI_IF_UNSPEC){

709

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

710

" incomplete without a network interface\n");

687

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

688

" without a network interface\n");

711

689

errno = EINVAL;

712

690

goto mandos_end;

713

691

}

731

709

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

732

710

perror_plus("if_indextoname");

733

711

} else {

734

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

735

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

712

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

713

ip, interface, port);

736

714

}

737

715

} else {

738

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

739

ip, (uintmax_t)port);

716

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

717

port);

740

718

}

741

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

742

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

752

730

perror_plus("inet_ntop");

753

731

} else {

754

732

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

755

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

733

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

756

734

}

757

735

}

758

736

}

786

764

while(true){

787

765

size_t out_size = strlen(out);

788

766

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

789

out_size - written));

767

out_size - written));

790

768

if(ret == -1){

791

769

int e = errno;

792

770

perror_plus("write");

812

790

}

813

791

814

792

if(debug){

815

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

793

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

816

794

}

817

795

818

796

if(quit_now){

820

798

goto mandos_end;

821

799

}

822

800

823

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

824

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

825

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

826

gnutls_transport_set_ptr(session,

827

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

828

803

829

804

if(quit_now){

830

805

errno = EINTR;

841

816

842

817

if(ret != GNUTLS_E_SUCCESS){

843

818

if(debug){

844

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

819

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

845

820

gnutls_perror(ret);

846

821

}

847

822

errno = EPROTO;

851

826

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

852

827

853

828

if(debug){

854

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

855

" %s\n", ip);

829

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

830

ip);

856

831

}

857

832

858

833

while(true){

863

838

}

864

839

865

840

buffer_capacity = incbuffer(&buffer, buffer_length,

866

buffer_capacity);

841

buffer_capacity);

867

842

if(buffer_capacity == 0){

868

843

int e = errno;

869

844

perror_plus("incbuffer");

896

871

}

897

872

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

898

873

if(ret < 0){

899

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

900

"***\n");

874

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

901

875

gnutls_perror(ret);

902

876

errno = EPROTO;

903

877

goto mandos_end;

904

878

}

905

879

break;

906

880

default:

907

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

908

" encrypted session with Mandos server\n");

881

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

882

" encrypted session with Mandos server\n");

909

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

910

884

errno = EIO;

911

885

goto mandos_end;

916

890

}

917

891

918

892

if(debug){

919

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

893

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

920

894

}

921

895

922

896

if(quit_now){

934

908

935

909

if(buffer_length > 0){

936

910

ssize_t decrypted_buffer_size;

937

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

938

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

939

914

if(decrypted_buffer_size >= 0){

940

915

941

916

written = 0;

951

926

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

952

927

int e = errno;

953

928

if(debug){

954

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

955

strerror(errno));

929

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

930

strerror(errno));

956

931

}

957

932

errno = e;

958

933

goto mandos_end;

1002

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1003

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1004

979

flags,

1005

void* mc){

1006

if(r == NULL){

1007

return;

1008

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1009

982

1010

983

/* Called whenever a service has been resolved successfully or

1011

984

timed out */

1017

990

switch(event){

1018

991

default:

1019

992

case AVAHI_RESOLVER_FAILURE:

1020

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

1021

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

1022

domain,

1023

avahi_strerror(avahi_server_errno

1024

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

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1025

996

break;

1026

997

1027

998

case AVAHI_RESOLVER_FOUND:

1029

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1030

1001

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

1031

1002

if(debug){

1032

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

1033

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

1034

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

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1035

1006

}

1036

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

1037

interface,

1038

avahi_proto_to_af(proto),

1039

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1040

1009

if(ret == 0){

1041

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1042

1011

} else {

1043

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

1044

avahi_proto_to_af(proto),

1045

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

1046

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

1047

" list\n", name);

1048

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1049

1014

}

1050

1015

}

1051

1016

}

1061

1026

const char *domain,

1062

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1063

1028

flags,

1064

void* mc){

1065

if(b == NULL){

1066

return;

1067

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1068

1031

1069

1032

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

1070

1033

is removed from the LAN */

1077

1040

default:

1078

1041

case AVAHI_BROWSER_FAILURE:

1079

1042

1080

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

1081

avahi_strerror(avahi_server_errno

1082

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

1083

avahi_simple_poll_quit(simple_poll);

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1084

1046

return;

1085

1047

1086

1048

case AVAHI_BROWSER_NEW:

1089

1051

the callback function is called the Avahi server will free the

1090

1052

resolver for us. */

1091

1053

1092

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

1093

interface, protocol, name, type,

1094

domain, protocol, 0,

1095

resolve_callback, mc) == NULL)

1096

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

1097

" %s\n", name,

1098

avahi_strerror(avahi_server_errno

1099

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

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

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

1058

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

1100

1059

break;

1101

1060

1102

1061

case AVAHI_BROWSER_REMOVE:

1105

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1106

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1107

1066

if(debug){

1108

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

1109

" searching...\n");

1067

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

1110

1068

}

1111

1069

break;

1112

1070

}

1121

1079

signal_received = sig;

1122

1080

int old_errno = errno;

1123

1081

/* set main loop to exit */

1124

if(simple_poll != NULL){

1125

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1126

1084

}

1127

1085

errno = old_errno;

1128

1086

}

1129

1087

1130

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

1131

int ret;

1132

error_t ret_errno;

1133

1134

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

1135

if(s < 0){

1136

ret_errno = errno;

1137

perror_plus("socket");

1138

errno = ret_errno;

1139

return false;

1140

}

1141

strcpy(ifr->ifr_name, ifname);

1142

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1143

if(ret == -1){

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

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

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

ret_errno = errno;

1146

perror_plus("ioctl SIOCGIFFLAGS");

1147

errno = ret_errno;

1145

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

1146

flagstring, if_entry->d_name);

1148

1147

}

1149

return false;

1148

free(flagstring);

1149

return 0;

1150

}

1151

return true;

1152

}

1153

1154

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

1155

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1156

1153

/* Reject the loopback device */

1157

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1158

1155

if(debug){

1159

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

1160

ifname);

1156

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

1157

if_entry->d_name);

1161

1158

}

1162

return false;

1159

return 0;

1163

1160

}

1164

1161

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

1165

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

1162

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

1166

1163

if(debug){

1167

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

1168

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

1164

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

1165

if_entry->d_name);

1169

1166

}

1170

return true;

1167

return 1;

1171

1168

}

1172

1169

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

1173

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

1170

if(not (flags & IFF_BROADCAST)){

1174

1171

if(debug){

1175

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1176

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

1172

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

1173

if_entry->d_name);

1177

1174

}

1178

return false;

1175

return 0;

1179

1176

}

1180

1177

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

1181

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1182

1179

if(debug){

1183

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

1184

ifname);

1180

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

1181

if_entry->d_name);

1185

1182

}

1186

return false;

1183

return 0;

1187

1184

}

1188

1189

1185

/* Accept this device */

1190

1186

if(debug){

1191

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

1192

}

1193

return true;

1194

}

1195

1196

/*

1197

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

1198

* corresponds to an acceptable network device.

1199

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

1200

*/

1201

int good_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

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

1216

return 0;

1187

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

1188

if_entry->d_name);

1217

1189

}

1218

1190

return 1;

1219

1191

}

1220

1192

1221

/*

1222

* This function determines if a network interface is up.

1223

*/

1224

bool interface_is_up(const char *interface){

1225

struct ifreq ifr;

1226

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

1227

if(debug){

1228

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

1229

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

1230

}

1231

return false;

1232

}

1233

1234

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

1235

}

1236

1237

/*

1238

* This function determines if a network interface is running

1239

*/

1240

bool interface_is_running(const char *interface){

1241

struct ifreq ifr;

1242

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

1243

if(debug){

1244

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

1245

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

1246

}

1247

return false;

1248

}

1249

1250

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

1251

}

1252

1253

1193

int notdotentries(const struct dirent *direntry){

1254

1194

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

1255

1195

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

1261

1201

return 1;

1262

1202

}

1263

1203

1264

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

1265

int runnable_hook(const struct dirent *direntry){

1266

int ret;

1267

size_t sret;

1268

struct stat st;

1269

1270

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

1271

/* Empty name? */

1272

return 0;

1273

}

1274

1275

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

1276

"abcdefghijklmnopqrstuvwxyz"

1277

"0123456789"

1278

"_-");

1279

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

1280

/* Contains non-allowed characters */

1281

if(debug){

1282

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

1283

direntry->d_name);

1284

}

1285

return 0;

1286

}

1287

1288

char *fullname = NULL;

1289

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

1290

if(ret < 0){

1291

perror_plus("asprintf");

1292

return 0;

1293

}

1294

1295

ret = stat(fullname, &st);

1296

if(ret == -1){

1297

if(debug){

1298

perror_plus("Could not stat hook");

1299

}

1300

return 0;

1301

}

1302

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

1303

/* Not a regular file */

1304

if(debug){

1305

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

1306

direntry->d_name);

1307

}

1308

return 0;

1309

}

1310

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

1311

/* Not executable */

1312

if(debug){

1313

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

1314

direntry->d_name);

1315

}

1316

return 0;

1317

}

1318

if(debug){

1319

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

1320

direntry->d_name);

1321

}

1322

return 1;

1323

}

1324

1325

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1326

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1327

1205

int ret;

1328

1206

struct timespec now;

1329

1207

struct timespec waited_time;

1330

1208

intmax_t block_time;

1331

1209

1332

1210

while(true){

1333

if(mc->current_server == NULL){

1211

if(mc.current_server == NULL){

1334

1212

if (debug){

1335

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

1336

" No timeout!\n");

1213

fprintf(stderr,

1214

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

1337

1215

}

1338

1216

ret = avahi_simple_poll_iterate(s, -1);

1339

1217

} else {

1340

1218

if (debug){

1341

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

1342

" it, or wait\n");

1219

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

1220

" or wait\n");

1343

1221

}

1344

1222

/* the current time */

1345

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1350

1228

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

1351

1229

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

1352

1230

waited_time.tv_sec = (now.tv_sec

1353

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

1231

- mc.current_server->last_seen.tv_sec);

1354

1232

waited_time.tv_nsec = (now.tv_nsec

1355

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

1233

- mc.current_server->last_seen.tv_nsec);

1356

1234

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

1357

1235

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

1358

1236

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

1361

1239

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

1362

1240

1363

1241

if (debug){

1364

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

1365

block_time);

1242

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

1366

1243

}

1367

1244

1368

1245

if(block_time <= 0){

1369

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

1370

mc->current_server->port,

1371

mc->current_server->if_index,

1372

mc->current_server->af, mc);

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1373

1250

if(ret == 0){

1374

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

1375

1252

return 0;

1376

1253

}

1377

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1378

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

1379

1256

if(ret == -1){

1380

1257

perror_plus("clock_gettime");

1381

1258

return -1;

1382

1259

}

1383

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

1260

mc.current_server = mc.current_server->next;

1384

1261

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

1385

1262

servers, but don't block */

1386

1263

}

1388

1265

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

1389

1266

}

1390

1267

if(ret != 0){

1391

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

1268

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

1392

1269

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

1393

1270

}

1394

1271

}

1395

1272

}

1396

1273

}

1397

1274

1398

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

1399

error_t raise_privileges(void){

1400

error_t old_errno = errno;

1401

error_t ret_errno = 0;

1402

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

1403

ret_errno = errno;

1404

perror_plus("seteuid");

1405

}

1406

errno = old_errno;

1407

return ret_errno;

1408

}

1409

1410

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

1411

error_t raise_privileges_permanently(void){

1412

error_t old_errno = errno;

1413

error_t ret_errno = raise_privileges();

1414

if(ret_errno != 0){

1415

errno = old_errno;

1416

return ret_errno;

1417

}

1418

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

1419

ret_errno = errno;

1420

perror_plus("seteuid");

1421

}

1422

errno = old_errno;

1423

return ret_errno;

1424

}

1425

1426

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

1427

error_t lower_privileges(void){

1428

error_t old_errno = errno;

1429

error_t ret_errno = 0;

1430

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

1431

ret_errno = errno;

1432

perror_plus("seteuid");

1433

}

1434

errno = old_errno;

1435

return ret_errno;

1436

}

1437

1438

/* Lower privileges permanently */

1439

error_t lower_privileges_permanently(void){

1440

error_t old_errno = errno;

1441

error_t ret_errno = 0;

1442

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

1443

ret_errno = errno;

1444

perror_plus("setuid");

1445

}

1446

errno = old_errno;

1447

return ret_errno;

1448

}

1449

1450

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

1451

const float delay){

1452

struct dirent **direntries;

1453

struct dirent *direntry;

1454

int ret;

1455

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

1456

alphasort);

1457

if(numhooks == -1){

1458

if(errno == ENOENT){

1459

if(debug){

1460

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

1461

" found\n", hookdir);

1462

}

1463

} else {

1464

perror_plus("scandir");

1465

}

1466

} else {

1467

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

1468

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

1469

direntry = direntries[i];

1470

char *fullname = NULL;

1471

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

1472

if(ret < 0){

1473

perror_plus("asprintf");

1474

continue;

1475

}

1476

if(debug){

1477

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

1478

direntry->d_name);

1479

}

1480

pid_t hook_pid = fork();

1481

if(hook_pid == 0){

1482

/* Child */

1483

/* Raise privileges */

1484

raise_privileges_permanently();

1485

/* Set group */

1486

errno = 0;

1487

ret = setgid(0);

1488

if(ret == -1){

1489

perror_plus("setgid");

1490

}

1491

/* Reset supplementary groups */

1492

errno = 0;

1493

ret = setgroups(0, NULL);

1494

if(ret == -1){

1495

perror_plus("setgroups");

1496

}

1497

dup2(devnull, STDIN_FILENO);

1498

close(devnull);

1499

dup2(STDERR_FILENO, STDOUT_FILENO);

1500

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

1501

if(ret == -1){

1502

perror_plus("setenv");

1503

_exit(EX_OSERR);

1504

}

1505

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

1506

if(ret == -1){

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

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

1511

if(ret == -1){

1512

perror_plus("setenv");

1513

_exit(EX_OSERR);

1514

}

1515

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

1516

if(ret == -1){

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

char *delaystring;

1521

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

1522

if(ret == -1){

1523

perror_plus("asprintf");

1524

_exit(EX_OSERR);

1525

}

1526

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

1527

if(ret == -1){

1528

free(delaystring);

1529

perror_plus("setenv");

1530

_exit(EX_OSERR);

1531

}

1532

free(delaystring);

1533

if(connect_to != NULL){

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

}

1540

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

1541

perror_plus("execl");

1542

_exit(EXIT_FAILURE);

1543

}

1544

} else {

1545

int status;

1546

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

1547

perror_plus("waitpid");

1548

free(fullname);

1549

continue;

1550

}

1551

if(WIFEXITED(status)){

1552

if(WEXITSTATUS(status) != 0){

1553

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

1554

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

1555

WEXITSTATUS(status));

1556

free(fullname);

1557

continue;

1558

}

1559

} else if(WIFSIGNALED(status)){

1560

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

1561

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

1562

WTERMSIG(status));

1563

free(fullname);

1564

continue;

1565

} else {

1566

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

1567

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

1568

free(fullname);

1569

continue;

1570

}

1571

}

1572

free(fullname);

1573

if(debug){

1574

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

1575

direntry->d_name);

1576

}

1577

}

1578

close(devnull);

1579

}

1580

return true;

1581

}

1582

1583

error_t bring_up_interface(const char *const interface,

1584

const float delay){

1585

int sd = -1;

1586

error_t old_errno = errno;

1587

error_t ret_errno = 0;

1588

int ret, ret_setflags;

1589

struct ifreq network;

1590

unsigned int if_index = if_nametoindex(interface);

1591

if(if_index == 0){

1592

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

1593

errno = old_errno;

1594

return ENXIO;

1595

}

1596

1597

if(quit_now){

1598

errno = old_errno;

1599

return EINTR;

1600

}

1601

1602

if(not interface_is_up(interface)){

1603

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

1604

ret_errno = errno;

1605

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

1606

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

1607

return ret_errno;

1608

}

1609

network.ifr_flags |= IFF_UP;

1610

1611

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1612

if(sd < 0){

1613

ret_errno = errno;

1614

perror_plus("socket");

1615

errno = old_errno;

1616

return ret_errno;

1617

}

1618

1619

if(quit_now){

1620

close(sd);

1621

errno = old_errno;

1622

return EINTR;

1623

}

1624

1625

if(debug){

1626

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

1627

interface);

1628

}

1629

1630

/* Raise priviliges */

1631

raise_privileges();

1632

1633

#ifdef __linux__

1634

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1635

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

1636

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

1637

bool restore_loglevel = true;

1638

if(ret_linux == -1){

1639

restore_loglevel = false;

1640

perror_plus("klogctl");

1641

}

1642

#endif /* __linux__ */

1643

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

1644

ret_errno = errno;

1645

#ifdef __linux__

1646

if(restore_loglevel){

1647

ret_linux = klogctl(7, NULL, 0);

1648

if(ret_linux == -1){

1649

perror_plus("klogctl");

1650

}

1651

}

1652

#endif /* __linux__ */

1653

1654

/* Lower privileges */

1655

lower_privileges();

1656

1657

/* Close the socket */

1658

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

1659

if(ret == -1){

1660

perror_plus("close");

1661

}

1662

1663

if(ret_setflags == -1){

1664

errno = ret_errno;

1665

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1666

errno = old_errno;

1667

return ret_errno;

1668

}

1669

} else if(debug){

1670

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

1671

interface);

1672

}

1673

1674

/* Sleep checking until interface is running.

1675

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

1676

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

1677

if(interface_is_running(interface)){

1678

break;

1679

}

1680

struct timespec sleeptime = { .tv_nsec = 250000000 };

1681

ret = nanosleep(&sleeptime, NULL);

1682

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

1683

perror_plus("nanosleep");

1684

}

1685

}

1686

1687

errno = old_errno;

1688

return 0;

1689

}

1690

1691

error_t take_down_interface(const char *const interface){

1692

int sd = -1;

1693

error_t old_errno = errno;

1694

error_t ret_errno = 0;

1695

int ret, ret_setflags;

1696

struct ifreq network;

1697

unsigned int if_index = if_nametoindex(interface);

1698

if(if_index == 0){

1699

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

1700

errno = old_errno;

1701

return ENXIO;

1702

}

1703

if(interface_is_up(interface)){

1704

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

1705

ret_errno = errno;

1706

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

1707

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

1708

return ret_errno;

1709

}

1710

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

1711

1712

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1713

if(sd < 0){

1714

ret_errno = errno;

1715

perror_plus("socket");

1716

errno = old_errno;

1717

return ret_errno;

1718

}

1719

1720

if(debug){

1721

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

1722

interface);

1723

}

1724

1725

/* Raise priviliges */

1726

raise_privileges();

1727

1728

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

1729

ret_errno = errno;

1730

1731

/* Lower privileges */

1732

lower_privileges();

1733

1734

/* Close the socket */

1735

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

1736

if(ret == -1){

1737

perror_plus("close");

1738

}

1739

1740

if(ret_setflags == -1){

1741

errno = ret_errno;

1742

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1743

errno = old_errno;

1744

return ret_errno;

1745

}

1746

} else if(debug){

1747

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

1748

interface);

1749

}

1750

1751

errno = old_errno;

1752

return 0;

1753

}

1754

1755

1275

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

1756

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

1757

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

1758

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

1759

1276

AvahiSServiceBrowser *sb = NULL;

1760

error_t ret_errno;

1277

int error;

1761

1278

int ret;

1762

1279

intmax_t tmpmax;

1763

1280

char *tmp;

1764

1281

int exitcode = EXIT_SUCCESS;

1765

char *interfaces = NULL;

1766

size_t interfaces_size = 0;

1767

char *interfaces_to_take_down = NULL;

1768

size_t interfaces_to_take_down_size = 0;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1769

1288

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

1770

1289

bool tempdir_created = false;

1771

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1772

1291

const char *seckey = PATHDIR "/" SECKEY;

1773

1292

const char *pubkey = PATHDIR "/" PUBKEY;

1774

char *interfaces_hooks = NULL;

1775

size_t interfaces_hooks_size = 0;

1776

1293

1777

1294

bool gnutls_initialized = false;

1778

1295

bool gpgme_initialized = false;

1840

1357

.group = 2 },

1841

1358

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

1842

1359

.arg = "SECONDS",

1843

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

1844

.group = 2 },

1845

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

1846

.arg = "DIR",

1847

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

1360

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

1848

1361

.group = 2 },

1849

1362

/*

1850

1363

* These reproduce what we would get without ARGP_NO_HELP

1869

1382

connect_to = arg;

1870

1383

break;

1871

1384

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

1872

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1873

(int)',');

1874

if(ret_errno != 0){

1875

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

1876

}

1385

interface = arg;

1877

1386

break;

1878

1387

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

1879

1388

seckey = arg;

1908

1417

argp_error(state, "Bad retry interval");

1909

1418

}

1910

1419

break;

1911

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

1912

hookdir = arg;

1913

break;

1914

1420

/*

1915

1421

* These reproduce what we would get without ARGP_NO_HELP

1916

1422

*/

1922

1428

argp_state_help(state, state->out_stream,

1923

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1924

1430

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

1925

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

1431

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

1926

1432

exit(argp_err_exit_status);

1927

1433

break;

1928

1434

default:

1955

1461

{

1956

1462

/* Work around Debian bug #633582:

1957

1463

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

1464

struct stat st;

1958

1465

1959

1466

/* Re-raise priviliges */

1960

if(raise_privileges() == 0){

1961

struct stat st;

1962

1963

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

1964

int seckey_fd = open(seckey, O_RDONLY);

1965

if(seckey_fd == -1){

1966

perror_plus("open");

1967

} else {

1968

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

1969

if(ret == -1){

1970

perror_plus("fstat");

1971

} else {

1972

if(S_ISREG(st.st_mode)

1973

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

1974

ret = fchown(seckey_fd, uid, gid);

1975

if(ret == -1){

1976

perror_plus("fchown");

1977

}

1978

}

1979

}

1980

TEMP_FAILURE_RETRY(close(seckey_fd));

1981

}

1982

}

1983

1984

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

1985

int pubkey_fd = open(pubkey, O_RDONLY);

1986

if(pubkey_fd == -1){

1987

perror_plus("open");

1988

} else {

1989

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

1990

if(ret == -1){

1991

perror_plus("fstat");

1992

} else {

1993

if(S_ISREG(st.st_mode)

1994

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

1995

ret = fchown(pubkey_fd, uid, gid);

1996

if(ret == -1){

1997

perror_plus("fchown");

1998

}

1999

}

2000

}

2001

TEMP_FAILURE_RETRY(close(pubkey_fd));

2002

}

2003

}

2004

2005

/* Lower privileges */

2006

errno = 0;

2007

ret = seteuid(uid);

2008

if(ret == -1){

2009

perror_plus("seteuid");

2010

}

2011

}

2012

}

2013

2014

/* Remove empty interface names */

2015

{

2016

char *interface = NULL;

2017

while((interface = argz_next(interfaces, interfaces_size,

2018

interface))){

2019

if(if_nametoindex(interface) == 0){

2020

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2021

fprintf_plus(stderr, "Not using nonexisting interface"

2022

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

2023

}

2024

argz_delete(&interfaces, &interfaces_size, interface);

2025

interface = NULL;

2026

}

2027

}

2028

}

2029

2030

/* Run network hooks */

2031

{

2032

2033

if(interfaces != NULL){

2034

interfaces_hooks = malloc(interfaces_size);

2035

if(interfaces_hooks == NULL){

2036

perror_plus("malloc");

2037

goto end;

2038

}

2039

memcpy(interfaces_hooks, interfaces, interfaces_size);

2040

interfaces_hooks_size = interfaces_size;

2041

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2042

(int)',');

2043

}

2044

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

2045

interfaces_hooks : "", delay)){

2046

goto end;

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

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

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

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

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

2047

1518

}

2048

1519

}

2049

1520

2050

1521

if(not debug){

2051

1522

avahi_set_log_function(empty_log);

2052

1523

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

2053

1549

2054

1550

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

2055

1551

from the signal handler */

2056

1552

/* Initialize the pseudo-RNG for Avahi */

2057

1553

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

2058

simple_poll = avahi_simple_poll_new();

2059

if(simple_poll == NULL){

2060

fprintf_plus(stderr,

2061

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

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

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

2062

1557

exitcode = EX_UNAVAILABLE;

2063

1558

goto end;

2064

1559

}

2126

1621

}

2127

1622

}

2128

1623

2129

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

2130

if(interfaces == NULL){

2131

struct dirent **direntries;

2132

/* Look for any good interfaces */

2133

ret = scandir(sys_class_net, &direntries, good_interface,

2134

alphasort);

2135

if(ret >= 1){

2136

/* Add all found interfaces to interfaces list */

2137

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

2138

ret_errno = argz_add(&interfaces, &interfaces_size,

2139

direntries[i]->d_name);

2140

if(ret_errno != 0){

2141

perror_plus("argz_add");

2142

continue;

2143

}

2144

if(debug){

2145

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

2146

direntries[i]->d_name);

2147

}

2148

}

2149

free(direntries);

1624

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

1709

}

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

break;

1729

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

2150

1760

} else {

2151

free(direntries);

2152

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

2153

exitcode = EXIT_FAILURE;

2154

goto end;

2155

}

2156

}

2157

2158

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

2159

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

2160

if(debug){

2161

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

2162

interfaces);

2163

}

2164

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2165

}

2166

2167

/* Bring up interfaces which are down */

2168

if(not (argz_count(interfaces, interfaces_size) == 1

2169

and strcmp(interfaces, "none") == 0)){

2170

char *interface = NULL;

2171

while((interface = argz_next(interfaces, interfaces_size,

2172

interface))){

2173

bool interface_was_up = interface_is_up(interface);

2174

ret = bring_up_interface(interface, delay);

2175

if(not interface_was_up){

2176

if(ret != 0){

2177

errno = ret;

2178

perror_plus("Failed to bring up interface");

2179

} else {

2180

ret_errno = argz_add(&interfaces_to_take_down,

2181

&interfaces_to_take_down_size,

2182

interface);

2183

}

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

2184

1765

}

2185

1766

}

2186

free(interfaces);

2187

interfaces = NULL;

2188

interfaces_size = 0;

2189

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

2190

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

2191

}

2192

1767

}

2193

1768

2194

1769

if(quit_now){

2195

1770

goto end;

2196

1771

}

2197

1772

2198

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

1773

ret = init_gnutls_global(pubkey, seckey);

2199

1774

if(ret == -1){

2200

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

1775

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

2201

1776

exitcode = EX_UNAVAILABLE;

2202

1777

goto end;

2203

1778

} else {

2218

1793

goto end;

2219

1794

}

2220

1795

2221

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

2222

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

1796

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

1797

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

2223

1798

exitcode = EX_UNAVAILABLE;

2224

1799

goto end;

2225

1800

} else {

2234

1809

/* Connect directly, do not use Zeroconf */

2235

1810

/* (Mainly meant for debugging) */

2236

1811

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

2237

2238

1812

if(address == NULL){

2239

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

1813

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

2240

1814

exitcode = EX_USAGE;

2241

1815

goto end;

2242

1816

}

2245

1819

goto end;

2246

1820

}

2247

1821

2248

in_port_t port;

1822

uint16_t port;

2249

1823

errno = 0;

2250

1824

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

2251

1825

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

2252

or tmpmax != (in_port_t)tmpmax){

2253

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2254

1828

exitcode = EX_USAGE;

2255

1829

goto end;

2256

1830

}

2259

1833

goto end;

2260

1834

}

2261

1835

2262

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

2263

1837

*address = '\0';

2264

1838

/* Colon in address indicates IPv6 */

2265

1839

int af;

2281

1855

}

2282

1856

2283

1857

while(not quit_now){

2284

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

2285

&mc);

1858

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

2286

1859

if(quit_now or ret == 0){

2287

1860

break;

2288

1861

}

2289

1862

if(debug){

2290

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

2291

(int)retry_interval);

1863

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

1864

(int)retry_interval);

2292

1865

}

2293

1866

sleep((int)retry_interval);

2294

1867

}

2296

1869

if (not quit_now){

2297

1870

exitcode = EXIT_SUCCESS;

2298

1871

}

2299

1872

2300

1873

goto end;

2301

1874

}

2302

1875

2314

1887

config.publish_domain = 0;

2315

1888

2316

1889

/* Allocate a new server */

2317

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2318

&config, NULL, NULL, &ret_errno);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2319

1893

2320

1894

/* Free the Avahi configuration data */

2321

1895

avahi_server_config_free(&config);

2323

1897

2324

1898

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

2325

1899

if(mc.server == NULL){

2326

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

2327

avahi_strerror(ret_errno));

1900

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

1901

avahi_strerror(error));

2328

1902

exitcode = EX_UNAVAILABLE;

2329

1903

goto end;

2330

1904

}

2336

1910

/* Create the Avahi service browser */

2337

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

2338

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2339

NULL, 0, browse_callback,

2340

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

2341

1914

if(sb == NULL){

2342

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

2343

avahi_strerror(avahi_server_errno(mc.server)));

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2344

1917

exitcode = EX_UNAVAILABLE;

2345

1918

goto end;

2346

1919

}

2352

1925

/* Run the main loop */

2353

1926

2354

1927

if(debug){

2355

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

1928

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

2356

1929

}

2357

1930

2358

ret = avahi_loop_with_timeout(simple_poll,

2359

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

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2360

1933

if(debug){

2361

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

2362

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

1934

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

1935

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

2363

1936

}

2364

1937

2365

1938

end:

2366

1939

2367

1940

if(debug){

2368

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

1941

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

2369

1942

}

2370

1943

2371

1944

/* Cleanup things */

2375

1948

if(mc.server != NULL)

2376

1949

avahi_server_free(mc.server);

2377

1950

2378

if(simple_poll != NULL)

2379

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2380

1953

2381

1954

if(gnutls_initialized){

2382

1955

gnutls_certificate_free_credentials(mc.cred);

2387

1960

if(gpgme_initialized){

2388

1961

gpgme_release(mc.ctx);

2389

1962

}

2390

1963

2391

1964

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

2392

1965

has seen */

2393

1966

if(mc.current_server != NULL){

2399

1972

}

2400

1973

}

2401

1974

2402

/* Re-raise priviliges */

2403

{

2404

raise_privileges();

2405

2406

/* Run network hooks */

2407

run_network_hooks("stop", interfaces_hooks != NULL ?

2408

interfaces_hooks : "", delay);

2409

2410

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

2411

{

2412

char *interface = NULL;

2413

while((interface=argz_next(interfaces_to_take_down,

2414

interfaces_to_take_down_size,

2415

interface))){

2416

ret_errno = take_down_interface(interface);

2417

if(ret_errno != 0){

2418

errno = ret_errno;

2419

perror_plus("Failed to take down interface");

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2420

1992

}

2421

1993

}

2422

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

2423

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

2424

" down\n");

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2425

2003

}

2426

2004

}

2427

2428

lower_privileges_permanently();

2429

2005

}

2430

2006

2431

free(interfaces_to_take_down);

2432

free(interfaces_hooks);

2433

2434

2007

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

2435

2008

if(tempdir_created){

2436

2009

struct dirent **direntries = NULL;

2449

2022

}

2450

2023

ret = remove(fullname);

2451

2024

if(ret == -1){

2452

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

2453

strerror(errno));

2025

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

2026

strerror(errno));

2454

2027

}

2455

2028

free(fullname);

2456

2029

}