/mandos/trunk : revision 1232

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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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* published by the Free Software Foundation, either version 3 of the

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* License, or (at your option) any later version.

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*

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* This program is distributed in the hope that it will be useful, but

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*

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* This file is part of Mandos.

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*

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* Mandos is free software: you can redistribute it and/or modify it

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* under the terms of the GNU General Public License as published by

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* the Free Software Foundation, either version 3 of the License, or

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* (at your option) any later version.

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*

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* Mandos is distributed in the hope that it will be useful, but

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

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* General Public License for more details.

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*

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* You should have received a copy of the GNU General Public License

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* along with this program. If not, see

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

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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */

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

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stdout, ferror(), remove() */

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stdout, ferror() */

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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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#include <stdbool.h> /* bool, false, true */

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#include <string.h> /* memset(), strcmp(), strlen(),

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strerror(), asprintf(), strcpy() */

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#include <string.h> /* strcmp(), strlen(), strerror(),

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asprintf(), strncpy(), strsignal()

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*/

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#include <sys/ioctl.h> /* ioctl */

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#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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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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inet_pton(), connect(),

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getnameinfo() */

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

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#include <dirent.h> /* opendir(), struct dirent, readdir()

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

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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program_invocation_short_name */

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

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#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,

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

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setgid(), pause(), _exit(),

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unlinkat(), lstat(), symlink() */

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

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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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argp_state, struct argp,

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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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#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

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#if GNUTLS_VERSION_NUMBER < 0x030600

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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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#elif GNUTLS_VERSION_NUMBER >= 0x030606

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#include <gnutls/x509.h> /* gnutls_pkcs_encrypt_flags_t,

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GNUTLS_PKCS_PLAIN,

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GNUTLS_PKCS_NULL_PASSWORD */

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#endif

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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 TLS_PRIVKEY "tls-privkey.pem"

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#define TLS_PUBKEY "tls-pubkey.pem"

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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 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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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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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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* 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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__attribute__((nonnull, warn_unused_result))

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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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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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char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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}

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

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__attribute__((nonnull, warn_unused_result))

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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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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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free(new_server);

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return false;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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free((char *)(new_server->ip));

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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

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} else {

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

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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;

237

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(*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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if(ret == -1){

241

perror_plus("clock_gettime");

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return false;

243

}

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return true;

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}

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

286

int old_errno = errno;

287

int ret = 0;

288

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

294

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

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

298

int old_errno = errno;

299

int ret = raise_privileges();

300

if(ret != 0){

301

errno = old_errno;

302

return ret;

303

}

304

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

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ret = errno;

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}

307

errno = old_errno;

308

return ret;

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}

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311

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

312

__attribute__((warn_unused_result))

313

int lower_privileges(void){

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int old_errno = errno;

315

int ret = 0;

316

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

317

ret = errno;

318

}

319

errno = old_errno;

320

return ret;

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}

322

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/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

325

int lower_privileges_permanently(void){

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int old_errno = errno;

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int ret = 0;

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

329

ret = errno;

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}

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errno = old_errno;

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return ret;

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}

334

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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){

338

__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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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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bool import_key(const char *filename){

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bool import_key(const char * const filename){

259

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int ret;

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int fd;

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gpgme_data_t pgp_data;

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return false;

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358

}

268

359

360

/* Workaround for systems without a real-time clock; see also

361

Debian bug #894495: <https://bugs.debian.org/894495> */

362

do {

363

{

364

time_t currtime = time(NULL);

365

if(currtime != (time_t)-1){

366

struct tm tm;

367

if(gmtime_r(&currtime, &tm) == NULL) {

368

perror_plus("gmtime_r");

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break;

370

}

371

if(tm.tm_year != 70 or tm.tm_mon != 0){

372

break;

373

}

374

if(debug){

375

fprintf_plus(stderr, "System clock is January 1970");

376

}

377

} else {

378

if(debug){

379

fprintf_plus(stderr, "System clock is invalid");

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

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"Setting system clock to key file mtime");

398

}

399

if(clock_settime(CLOCK_REALTIME, &keystat.st_mtim) != 0){

400

perror_plus("clock_settime");

401

}

402

ret = lower_privileges();

403

if(ret != 0){

404

errno = ret;

405

perror_plus("Failed to lower privileges");

406

}

407

} while(false);

408

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

270

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if(rc != GPG_ERR_NO_ERROR){

271

411

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;

281

421

}

422

{

423

gpgme_import_result_t import_result

424

= gpgme_op_import_result(mc->ctx);

425

if((import_result->imported < 1

426

or import_result->not_imported > 0)

427

and import_result->unchanged == 0){

428

fprintf_plus(stderr, "bad gpgme_op_import_results:\n");

429

fprintf_plus(stderr,

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"The total number of considered keys: %d\n",

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import_result->considered);

432

fprintf_plus(stderr,

433

"The number of keys without user ID: %d\n",

434

import_result->no_user_id);

435

fprintf_plus(stderr,

436

"The total number of imported keys: %d\n",

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import_result->imported);

438

fprintf_plus(stderr, "The number of imported RSA keys: %d\n",

439

import_result->imported_rsa);

440

fprintf_plus(stderr, "The number of unchanged keys: %d\n",

441

import_result->unchanged);

442

fprintf_plus(stderr, "The number of new user IDs: %d\n",

443

import_result->new_user_ids);

444

fprintf_plus(stderr, "The number of new sub keys: %d\n",

445

import_result->new_sub_keys);

446

fprintf_plus(stderr, "The number of new signatures: %d\n",

447

import_result->new_signatures);

448

fprintf_plus(stderr, "The number of new revocations: %d\n",

449

import_result->new_revocations);

450

fprintf_plus(stderr,

451

"The total number of secret keys read: %d\n",

452

import_result->secret_read);

453

fprintf_plus(stderr,

454

"The number of imported secret keys: %d\n",

455

import_result->secret_imported);

456

fprintf_plus(stderr,

457

"The number of unchanged secret keys: %d\n",

458

import_result->secret_unchanged);

459

fprintf_plus(stderr, "The number of keys not imported: %d\n",

460

import_result->not_imported);

461

for(gpgme_import_status_t import_status

462

= import_result->imports;

463

import_status != NULL;

464

import_status = import_status->next){

465

fprintf_plus(stderr, "Import status for key: %s\n",

466

import_status->fpr);

467

if(import_status->result != GPG_ERR_NO_ERROR){

468

fprintf_plus(stderr, "Import result: %s: %s\n",

469

gpgme_strsource(import_status->result),

470

gpgme_strerror(import_status->result));

471

}

472

fprintf_plus(stderr, "Key status:\n");

473

fprintf_plus(stderr,

474

import_status->status & GPGME_IMPORT_NEW

475

? "The key was new.\n"

476

: "The key was not new.\n");

477

fprintf_plus(stderr,

478

import_status->status & GPGME_IMPORT_UID

479

? "The key contained new user IDs.\n"

480

: "The key did not contain new user IDs.\n");

481

fprintf_plus(stderr,

482

import_status->status & GPGME_IMPORT_SIG

483

? "The key contained new signatures.\n"

484

: "The key did not contain new signatures.\n");

485

fprintf_plus(stderr,

486

import_status->status & GPGME_IMPORT_SUBKEY

487

? "The key contained new sub keys.\n"

488

: "The key did not contain new sub keys.\n");

489

fprintf_plus(stderr,

490

import_status->status & GPGME_IMPORT_SECRET

491

? "The key contained a secret key.\n"

492

: "The key did not contain a secret key.\n");

493

}

494

return false;

495

}

496

}

282

497

283

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

498

ret = close(fd);

284

499

if(ret == -1){

285

500

perror_plus("close");

286

501

}

325

540

/* Create new GPGME "context" */

326

541

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

327

542

if(rc != GPG_ERR_NO_ERROR){

328

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

329

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

330

gpgme_strerror(rc));

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

331

545

return false;

332

546

}

333

547

342

556

* Decrypt OpenPGP data.

343

557

* Returns -1 on error

344

558

*/

559

__attribute__((nonnull, warn_unused_result))

345

560

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

561

size_t crypto_size,

347

562

char **plaintext,

368

583

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

369

584

rc = gpgme_data_new(&dh_plain);

370

585

if(rc != GPG_ERR_NO_ERROR){

371

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

372

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

586

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

373

587

gpgme_strsource(rc), gpgme_strerror(rc));

374

588

gpgme_data_release(dh_crypto);

375

589

return -1;

388

602

if(result == NULL){

389

603

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

390

604

} else {

391

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

392

result->unsupported_algorithm);

393

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

394

result->wrong_key_usage);

605

if(result->unsupported_algorithm != NULL) {

606

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

607

result->unsupported_algorithm);

608

}

609

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

610

result->wrong_key_usage ? "Yes" : "No");

395

611

if(result->file_name != NULL){

396

612

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

397

613

}

398

gpgme_recipient_t recipient;

399

recipient = result->recipients;

400

while(recipient != NULL){

614

615

for(gpgme_recipient_t r = result->recipients; r != NULL;

616

r = r->next){

401

617

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);

618

gpgme_pubkey_algo_name(r->pubkey_algo));

619

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

405

620

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

408

recipient = recipient->next;

621

r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");

409

622

}

410

623

}

411

624

}

467

680

return plaintext_length;

468

681

}

469

682

470

static const char * safer_gnutls_strerror(int value){

683

__attribute__((warn_unused_result, const))

684

static const char *safe_string(const char *str){

685

if(str == NULL)

686

return "(unknown)";

687

return str;

688

}

689

690

__attribute__((warn_unused_result))

691

static const char *safer_gnutls_strerror(int value){

471

692

const char *ret = gnutls_strerror(value);

472

if(ret == NULL)

473

ret = "(unknown)";

474

return ret;

693

return safe_string(ret);

475

694

}

476

695

477

696

/* GnuTLS log function callback */

697

__attribute__((nonnull))

478

698

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

479

699

const char* string){

480

700

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

481

701

}

482

702

703

__attribute__((nonnull(1, 2, 4), warn_unused_result))

483

704

static int init_gnutls_global(const char *pubkeyfilename,

484

705

const char *seckeyfilename,

706

const char *dhparamsfilename,

485

707

mandos_context *mc){

486

708

int ret;

487

709

489

711

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

490

712

}

491

713

492

ret = gnutls_global_init();

493

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

496

return -1;

497

}

498

499

714

if(debug){

500

715

/* "Use a log level over 10 to enable all debugging options."

501

716

* - GnuTLS manual

509

724

if(ret != GNUTLS_E_SUCCESS){

510

725

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

511

726

safer_gnutls_strerror(ret));

512

gnutls_global_deinit();

513

727

return -1;

514

728

}

515

729

516

730

if(debug){

517

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

518

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

731

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

732

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

519

733

pubkeyfilename,

520

734

seckeyfilename);

521

735

}

522

736

737

#if GNUTLS_VERSION_NUMBER >= 0x030606

738

ret = gnutls_certificate_set_rawpk_key_file

739

(mc->cred, pubkeyfilename, seckeyfilename,

740

GNUTLS_X509_FMT_PEM, /* format */

741

NULL, /* pass */

742

/* key_usage */

743

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

744

NULL, /* names */

745

0, /* names_length */

746

/* privkey_flags */

747

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

748

0); /* pkcs11_flags */

749

#elif GNUTLS_VERSION_NUMBER < 0x030600

523

750

ret = gnutls_certificate_set_openpgp_key_file

524

751

(mc->cred, pubkeyfilename, seckeyfilename,

525

752

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

755

#endif

526

756

if(ret != GNUTLS_E_SUCCESS){

527

757

fprintf_plus(stderr,

528

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

758

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

529

759

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

530

760

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

531

761

safer_gnutls_strerror(ret));

540

770

safer_gnutls_strerror(ret));

541

771

goto globalfail;

542

772

}

543

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

544

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

547

goto globalfail;

548

}

549

550

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

773

/* If a Diffie-Hellman parameters file was given, try to use it */

774

if(dhparamsfilename != NULL){

775

gnutls_datum_t params = { .data = NULL, .size = 0 };

776

do {

777

int dhpfile = open(dhparamsfilename, O_RDONLY);

778

if(dhpfile == -1){

779

perror_plus("open");

780

dhparamsfilename = NULL;

781

break;

782

}

783

size_t params_capacity = 0;

784

while(true){

785

params_capacity = incbuffer((char **)&params.data,

786

(size_t)params.size,

787

(size_t)params_capacity);

788

if(params_capacity == 0){

789

perror_plus("incbuffer");

790

free(params.data);

791

params.data = NULL;

792

dhparamsfilename = NULL;

793

break;

794

}

795

ssize_t bytes_read = read(dhpfile,

796

params.data + params.size,

797

BUFFER_SIZE);

798

/* EOF */

799

if(bytes_read == 0){

800

break;

801

}

802

/* check bytes_read for failure */

803

if(bytes_read < 0){

804

perror_plus("read");

805

free(params.data);

806

params.data = NULL;

807

dhparamsfilename = NULL;

808

break;

809

}

810

params.size += (unsigned int)bytes_read;

811

}

812

ret = close(dhpfile);

813

if(ret == -1){

814

perror_plus("close");

815

}

816

if(params.data == NULL){

817

dhparamsfilename = NULL;

818

}

819

if(dhparamsfilename == NULL){

820

break;

821

}

822

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

823

GNUTLS_X509_FMT_PEM);

824

if(ret != GNUTLS_E_SUCCESS){

825

fprintf_plus(stderr, "Failed to parse DH parameters in file"

826

" \"%s\": %s\n", dhparamsfilename,

827

safer_gnutls_strerror(ret));

828

dhparamsfilename = NULL;

829

}

830

free(params.data);

831

} while(false);

832

}

833

if(dhparamsfilename == NULL){

834

if(mc->dh_bits == 0){

835

#if GNUTLS_VERSION_NUMBER < 0x030600

836

/* Find out the optimal number of DH bits */

837

/* Try to read the private key file */

838

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

839

do {

840

int secfile = open(seckeyfilename, O_RDONLY);

841

if(secfile == -1){

842

perror_plus("open");

843

break;

844

}

845

size_t buffer_capacity = 0;

846

while(true){

847

buffer_capacity = incbuffer((char **)&buffer.data,

848

(size_t)buffer.size,

849

(size_t)buffer_capacity);

850

if(buffer_capacity == 0){

851

perror_plus("incbuffer");

852

free(buffer.data);

853

buffer.data = NULL;

854

break;

855

}

856

ssize_t bytes_read = read(secfile,

857

buffer.data + buffer.size,

858

BUFFER_SIZE);

859

/* EOF */

860

if(bytes_read == 0){

861

break;

862

}

863

/* check bytes_read for failure */

864

if(bytes_read < 0){

865

perror_plus("read");

866

free(buffer.data);

867

buffer.data = NULL;

868

break;

869

}

870

buffer.size += (unsigned int)bytes_read;

871

}

872

close(secfile);

873

} while(false);

874

/* If successful, use buffer to parse private key */

875

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

876

if(buffer.data != NULL){

877

{

878

gnutls_openpgp_privkey_t privkey = NULL;

879

ret = gnutls_openpgp_privkey_init(&privkey);

880

if(ret != GNUTLS_E_SUCCESS){

881

fprintf_plus(stderr, "Error initializing OpenPGP key"

882

" structure: %s",

883

safer_gnutls_strerror(ret));

884

free(buffer.data);

885

buffer.data = NULL;

886

} else {

887

ret = gnutls_openpgp_privkey_import

888

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

889

if(ret != GNUTLS_E_SUCCESS){

890

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

891

safer_gnutls_strerror(ret));

892

privkey = NULL;

893

}

894

free(buffer.data);

895

buffer.data = NULL;

896

if(privkey != NULL){

897

/* Use private key to suggest an appropriate

898

sec_param */

899

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

900

gnutls_openpgp_privkey_deinit(privkey);

901

if(debug){

902

fprintf_plus(stderr, "This OpenPGP key implies using"

903

" a GnuTLS security parameter \"%s\".\n",

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)));

906

}

907

}

908

}

909

}

910

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

911

/* Err on the side of caution */

912

sec_param = GNUTLS_SEC_PARAM_ULTRA;

913

if(debug){

914

fprintf_plus(stderr, "Falling back to security parameter"

915

" \"%s\"\n",

916

safe_string(gnutls_sec_param_get_name

917

(sec_param)));

918

}

919

}

920

}

921

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

922

if(uret != 0){

923

mc->dh_bits = uret;

924

if(debug){

925

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

926

" implies %u DH bits; using that.\n",

927

safe_string(gnutls_sec_param_get_name

928

(sec_param)),

929

mc->dh_bits);

930

}

931

} else {

932

fprintf_plus(stderr, "Failed to get implied number of DH"

933

" bits for security parameter \"%s\"): %s\n",

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)),

936

safer_gnutls_strerror(ret));

937

goto globalfail;

938

}

939

#endif

940

} else { /* dh_bits != 0 */

941

if(debug){

942

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

943

mc->dh_bits);

944

}

945

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

946

if(ret != GNUTLS_E_SUCCESS){

947

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"

948

" bits): %s\n", mc->dh_bits,

949

safer_gnutls_strerror(ret));

950

goto globalfail;

951

}

952

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

953

}

954

}

551

955

552

956

return 0;

553

957

554

958

globalfail:

555

959

556

960

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_global_deinit();

558

961

gnutls_dh_params_deinit(mc->dh_params);

559

962

return -1;

560

963

}

561

964

965

__attribute__((nonnull, warn_unused_result))

562

966

static int init_gnutls_session(gnutls_session_t *session,

563

967

mandos_context *mc){

564

968

int ret;

565

969

/* GnuTLS session creation */

566

970

do {

567

ret = gnutls_init(session, GNUTLS_SERVER);

971

ret = gnutls_init(session, (GNUTLS_SERVER

972

#if GNUTLS_VERSION_NUMBER >= 0x030506

973

| GNUTLS_NO_TICKETS

974

#endif

975

#if GNUTLS_VERSION_NUMBER >= 0x030606

976

| GNUTLS_ENABLE_RAWPK

977

#endif

978

));

568

979

if(quit_now){

569

980

return -1;

570

981

}

611

1022

/* ignore client certificate if any. */

612

1023

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

1024

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

615

616

1025

return 0;

617

1026

}

618

1027

620

1029

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

621

1030

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

622

1031

1032

/* Helper function to add_local_route() and delete_local_route() */

1033

__attribute__((nonnull, warn_unused_result))

1034

static bool add_delete_local_route(const bool add,

1035

const char *address,

1036

AvahiIfIndex if_index){

1037

int ret;

1038

char helper[] = "mandos-client-iprouteadddel";

1039

char add_arg[] = "add";

1040

char delete_arg[] = "delete";

1041

char debug_flag[] = "--debug";

1042

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1043

if(pluginhelperdir == NULL){

1044

if(debug){

1045

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1046

" variable not set; cannot run helper\n");

1047

}

1048

return false;

1049

}

1050

1051

char interface[IF_NAMESIZE];

1052

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

1053

perror_plus("if_indextoname");

1054

return false;

1055

}

1056

1057

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

1058

if(devnull == -1){

1059

perror_plus("open(\"/dev/null\", O_RDONLY)");

1060

return false;

1061

}

1062

pid_t pid = fork();

1063

if(pid == 0){

1064

/* Child */

1065

/* Raise privileges */

1066

errno = raise_privileges_permanently();

1067

if(errno != 0){

1068

perror_plus("Failed to raise privileges");

1069

/* _exit(EX_NOPERM); */

1070

} else {

1071

/* Set group */

1072

errno = 0;

1073

ret = setgid(0);

1074

if(ret == -1){

1075

perror_plus("setgid");

1076

close(devnull);

1077

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

close(devnull);

1085

_exit(EX_NOPERM);

1086

}

1087

}

1088

ret = dup2(devnull, STDIN_FILENO);

1089

if(ret == -1){

1090

perror_plus("dup2(devnull, STDIN_FILENO)");

1091

close(devnull);

1092

_exit(EX_OSERR);

1093

}

1094

ret = close(devnull);

1095

if(ret == -1){

1096

perror_plus("close");

1097

}

1098

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1099

if(ret == -1){

1100

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

1101

_exit(EX_OSERR);

1102

}

1103

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

1104

O_RDONLY

1105

| O_DIRECTORY

1106

| O_PATH

1107

| O_CLOEXEC));

1108

if(helperdir_fd == -1){

1109

perror_plus("open");

1110

_exit(EX_UNAVAILABLE);

1111

}

1112

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

1113

helper, O_RDONLY));

1114

if(helper_fd == -1){

1115

perror_plus("openat");

1116

close(helperdir_fd);

1117

_exit(EX_UNAVAILABLE);

1118

}

1119

close(helperdir_fd);

1120

#ifdef __GNUC__

1121

#pragma GCC diagnostic push

1122

#pragma GCC diagnostic ignored "-Wcast-qual"

1123

#endif

1124

if(fexecve(helper_fd, (char *const [])

1125

{ helper, add ? add_arg : delete_arg, (char *)address,

1126

interface, debug ? debug_flag : NULL, NULL },

1127

environ) == -1){

1128

#ifdef __GNUC__

1129

#pragma GCC diagnostic pop

1130

#endif

1131

perror_plus("fexecve");

1132

_exit(EXIT_FAILURE);

1133

}

1134

}

1135

if(pid == -1){

1136

perror_plus("fork");

1137

close(devnull);

1138

return false;

1139

}

1140

ret = close(devnull);

1141

if(ret == -1){

1142

perror_plus("close");

1143

}

1144

int status;

1145

pid_t pret = -1;

1146

errno = 0;

1147

do {

1148

pret = waitpid(pid, &status, 0);

1149

if(pret == -1 and errno == EINTR and quit_now){

1150

int errno_raising = 0;

1151

if((errno = raise_privileges()) != 0){

1152

errno_raising = errno;

1153

perror_plus("Failed to raise privileges in order to"

1154

" kill helper program");

1155

}

1156

if(kill(pid, SIGTERM) == -1){

1157

perror_plus("kill");

1158

}

1159

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

1160

perror_plus("Failed to lower privileges after killing"

1161

" helper program");

1162

}

1163

return false;

1164

}

1165

} while(pret == -1 and errno == EINTR);

1166

if(pret == -1){

1167

perror_plus("waitpid");

1168

return false;

1169

}

1170

if(WIFEXITED(status)){

1171

if(WEXITSTATUS(status) != 0){

1172

fprintf_plus(stderr, "Error: iprouteadddel exited"

1173

" with status %d\n", WEXITSTATUS(status));

1174

return false;

1175

}

1176

return true;

1177

}

1178

if(WIFSIGNALED(status)){

1179

fprintf_plus(stderr, "Error: iprouteadddel died by"

1180

" signal %d\n", WTERMSIG(status));

1181

return false;

1182

}

1183

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

1184

return false;

1185

}

1186

1187

__attribute__((nonnull, warn_unused_result))

1188

static bool add_local_route(const char *address,

1189

AvahiIfIndex if_index){

1190

if(debug){

1191

fprintf_plus(stderr, "Adding route to %s\n", address);

1192

}

1193

return add_delete_local_route(true, address, if_index);

1194

}

1195

1196

__attribute__((nonnull, warn_unused_result))

1197

static bool delete_local_route(const char *address,

1198

AvahiIfIndex if_index){

1199

if(debug){

1200

fprintf_plus(stderr, "Removing route to %s\n", address);

1201

}

1202

return add_delete_local_route(false, address, if_index);

1203

}

1204

623

1205

/* Called when a Mandos server is found */

1206

__attribute__((nonnull, warn_unused_result))

624

1207

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

625

1208

AvahiIfIndex if_index,

626

1209

int af, mandos_context *mc){

627

1210

int ret, tcp_sd = -1;

628

1211

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1212

struct sockaddr_storage to;

633

1213

char *buffer = NULL;

634

1214

char *decrypted_buffer = NULL;

635

1215

size_t buffer_length = 0;

638

1218

int retval = -1;

639

1219

gnutls_session_t session;

640

1220

int pf; /* Protocol family */

1221

bool route_added = false;

641

1222

642

1223

errno = 0;

643

1224

665

1246

bool match = false;

666

1247

{

667

1248

char *interface = NULL;

668

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

669

interface))){

1249

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

1250

mc->interfaces_size,

1251

interface))){

670

1252

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

671

1253

match = true;

672

1254

break;

701

1283

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

702

1284

}

703

1285

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

1286

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

705

1287

if(tcp_sd < 0){

706

1288

int e = errno;

707

1289

perror_plus("socket");

714

1296

goto mandos_end;

715

1297

}

716

1298

717

memset(&to, 0, sizeof(to));

718

1299

if(af == AF_INET6){

719

to.in6.sin6_family = (sa_family_t)af;

720

ret = inet_pton(af, ip, &to.in6.sin6_addr);

1300

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1301

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1302

ret = inet_pton(af, ip, &to6->sin6_addr);

721

1303

} else { /* IPv4 */

722

to.in.sin_family = (sa_family_t)af;

723

ret = inet_pton(af, ip, &to.in.sin_addr);

1304

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1305

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1306

ret = inet_pton(af, ip, &to4->sin_addr);

724

1307

}

725

1308

if(ret < 0 ){

726

1309

int e = errno;

735

1318

goto mandos_end;

736

1319

}

737

1320

if(af == AF_INET6){

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

743

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

744

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

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

1321

((struct sockaddr_in6 *)&to)->sin6_port = htons(port);

1322

if(IN6_IS_ADDR_LINKLOCAL

1323

(&((struct sockaddr_in6 *)&to)->sin6_addr)){

748

1324

if(if_index == AVAHI_IF_UNSPEC){

749

1325

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

750

1326

" incomplete without a network interface\n");

752

1328

goto mandos_end;

753

1329

}

754

1330

/* Set the network interface number as scope */

755

to.in6.sin6_scope_id = (uint32_t)if_index;

1331

((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;

756

1332

}

757

1333

} else {

758

to.in.sin_port = htons(port);

1334

((struct sockaddr_in *)&to)->sin_port = htons(port);

759

1335

}

760

1336

761

1337

if(quit_now){

778

1354

}

779

1355

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

780

1356

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

781

const char *pcret;

782

if(af == AF_INET6){

783

pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,

784

sizeof(addrstr));

785

} else {

786

pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,

787

sizeof(addrstr));

788

}

789

if(pcret == NULL){

790

perror_plus("inet_ntop");

791

} else {

792

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

793

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

794

}

795

}

796

}

797

798

if(quit_now){

799

errno = EINTR;

800

goto mandos_end;

801

}

802

803

if(af == AF_INET6){

804

ret = connect(tcp_sd, &to.in6, sizeof(to));

805

} else {

806

ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */

807

}

808

if(ret < 0){

809

if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){

810

int e = errno;

811

perror_plus("connect");

812

errno = e;

813

}

814

goto mandos_end;

815

}

816

817

if(quit_now){

818

errno = EINTR;

819

goto mandos_end;

1357

if(af == AF_INET6){

1358

ret = getnameinfo((struct sockaddr *)&to,

1359

sizeof(struct sockaddr_in6),

1360

addrstr, sizeof(addrstr), NULL, 0,

1361

NI_NUMERICHOST);

1362

} else {

1363

ret = getnameinfo((struct sockaddr *)&to,

1364

sizeof(struct sockaddr_in),

1365

addrstr, sizeof(addrstr), NULL, 0,

1366

NI_NUMERICHOST);

1367

}

1368

if(ret == EAI_SYSTEM){

1369

perror_plus("getnameinfo");

1370

} else if(ret != 0) {

1371

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

1372

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

1373

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

1374

}

1375

}

1376

1377

if(quit_now){

1378

errno = EINTR;

1379

goto mandos_end;

1380

}

1381

1382

while(true){

1383

if(af == AF_INET6){

1384

ret = connect(tcp_sd, (struct sockaddr *)&to,

1385

sizeof(struct sockaddr_in6));

1386

} else {

1387

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

1388

sizeof(struct sockaddr_in));

1389

}

1390

if(ret < 0){

1391

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1392

and if_index != AVAHI_IF_UNSPEC

1393

and connect_to == NULL

1394

and not route_added and

1395

((af == AF_INET6 and not

1396

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1397

&to)->sin6_addr)))

1398

or (af == AF_INET and

1399

/* Not a a IPv4LL address */

1400

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1401

& 0xFFFF0000L) != 0xA9FE0000L))){

1402

/* Work around Avahi bug - Avahi does not announce link-local

1403

addresses if it has a global address, so local hosts with

1404

*only* a link-local address (e.g. Mandos clients) cannot

1405

connect to a Mandos server announced by Avahi on a server

1406

host with a global address. Work around this by retrying

1407

with an explicit route added with the server's address.

1408

1409

Avahi bug reference:

1410

https://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1411

https://bugs.debian.org/587961

1412

*/

1413

if(debug){

1414

fprintf_plus(stderr, "Mandos server unreachable, trying"

1415

" direct route\n");

1416

}

1417

int e = errno;

1418

route_added = add_local_route(ip, if_index);

1419

if(route_added){

1420

continue;

1421

}

1422

errno = e;

1423

}

1424

if(errno != ECONNREFUSED or debug){

1425

int e = errno;

1426

perror_plus("connect");

1427

errno = e;

1428

}

1429

goto mandos_end;

1430

}

1431

1432

if(quit_now){

1433

errno = EINTR;

1434

goto mandos_end;

1435

}

1436

break;

820

1437

}

821

1438

822

1439

const char *out = mandos_protocol_version;

976

1593

&decrypted_buffer, mc);

977

1594

if(decrypted_buffer_size >= 0){

978

1595

1596

clearerr(stdout);

979

1597

written = 0;

980

1598

while(written < (size_t) decrypted_buffer_size){

981

1599

if(quit_now){

997

1615

}

998

1616

written += (size_t)ret;

999

1617

}

1618

ret = fflush(stdout);

1619

if(ret != 0){

1620

int e = errno;

1621

if(debug){

1622

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

1623

strerror(errno));

1624

}

1625

errno = e;

1626

goto mandos_end;

1627

}

1000

1628

retval = 0;

1001

1629

}

1002

1630

}

1005

1633

1006

1634

mandos_end:

1007

1635

{

1636

if(route_added){

1637

if(not delete_local_route(ip, if_index)){

1638

fprintf_plus(stderr, "Failed to delete local route to %s on"

1639

" interface %d", ip, if_index);

1640

}

1641

}

1008

1642

int e = errno;

1009

1643

free(decrypted_buffer);

1010

1644

free(buffer);

1011

1645

if(tcp_sd >= 0){

1012

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

1646

ret = close(tcp_sd);

1013

1647

}

1014

1648

if(ret == -1){

1015

1649

if(e == 0){

1040

1674

AVAHI_GCC_UNUSED AvahiStringList *txt,

1041

1675

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1042

1676

flags,

1043

void* mc){

1677

void *mc){

1044

1678

if(r == NULL){

1045

1679

return;

1046

1680

}

1049

1683

timed out */

1050

1684

1051

1685

if(quit_now){

1686

avahi_s_service_resolver_free(r);

1052

1687

return;

1053

1688

}

1054

1689

1099

1734

const char *domain,

1100

1735

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1101

1736

flags,

1102

void* mc){

1737

void *mc){

1103

1738

if(b == NULL){

1104

1739

return;

1105

1740

}

1165

1800

errno = old_errno;

1166

1801

}

1167

1802

1803

__attribute__((nonnull, warn_unused_result))

1168

1804

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

1169

1805

int ret;

1170

error_t ret_errno;

1806

int old_errno;

1171

1807

1172

1808

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

1173

1809

if(s < 0){

1174

ret_errno = errno;

1810

old_errno = errno;

1175

1811

perror_plus("socket");

1176

errno = ret_errno;

1812

errno = old_errno;

1177

1813

return false;

1178

1814

}

1179

strcpy(ifr->ifr_name, ifname);

1815

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1816

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1180

1817

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1181

1818

if(ret == -1){

1182

1819

if(debug){

1183

ret_errno = errno;

1820

old_errno = errno;

1184

1821

perror_plus("ioctl SIOCGIFFLAGS");

1185

errno = ret_errno;

1822

errno = old_errno;

1823

}

1824

if((close(s) == -1) and debug){

1825

old_errno = errno;

1826

perror_plus("close");

1827

errno = old_errno;

1186

1828

}

1187

1829

return false;

1188

1830

}

1831

if((close(s) == -1) and debug){

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1189

1836

return true;

1190

1837

}

1191

1838

1839

__attribute__((nonnull, warn_unused_result))

1192

1840

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

1193

1841

1194

1842

/* Reject the loopback device */

1236

1884

* corresponds to an acceptable network device.

1237

1885

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

1238

1886

*/

1887

__attribute__((nonnull, warn_unused_result))

1239

1888

int good_interface(const struct dirent *if_entry){

1240

1889

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

1241

1890

return 0;

1259

1908

/*

1260

1909

* This function determines if a network interface is up.

1261

1910

*/

1911

__attribute__((nonnull, warn_unused_result))

1262

1912

bool interface_is_up(const char *interface){

1263

1913

struct ifreq ifr;

1264

1914

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

1275

1925

/*

1276

1926

* This function determines if a network interface is running

1277

1927

*/

1928

__attribute__((nonnull, warn_unused_result))

1278

1929

bool interface_is_running(const char *interface){

1279

1930

struct ifreq ifr;

1280

1931

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

1288

1939

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

1289

1940

}

1290

1941

1942

__attribute__((nonnull, pure, warn_unused_result))

1291

1943

int notdotentries(const struct dirent *direntry){

1292

1944

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

1293

1945

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

1300

1952

}

1301

1953

1302

1954

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

1955

__attribute__((nonnull, warn_unused_result))

1303

1956

int runnable_hook(const struct dirent *direntry){

1304

1957

int ret;

1305

1958

size_t sret;

1313

1966

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

1314

1967

"abcdefghijklmnopqrstuvwxyz"

1315

1968

"0123456789"

1316

"_-");

1969

"_.-");

1317

1970

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

1318

1971

/* Contains non-allowed characters */

1319

1972

if(debug){

1323

1976

return 0;

1324

1977

}

1325

1978

1326

char *fullname = NULL;

1327

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

1328

if(ret < 0){

1329

perror_plus("asprintf");

1330

return 0;

1331

}

1332

1333

ret = stat(fullname, &st);

1979

ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);

1334

1980

if(ret == -1){

1335

1981

if(debug){

1336

1982

perror_plus("Could not stat hook");

1360

2006

return 1;

1361

2007

}

1362

2008

2009

__attribute__((nonnull, warn_unused_result))

1363

2010

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

2011

mandos_context *mc){

1365

2012

int ret;

1369

2016

1370

2017

while(true){

1371

2018

if(mc->current_server == NULL){

1372

if (debug){

2019

if(debug){

1373

2020

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

1374

2021

" No timeout!\n");

1375

2022

}

1376

2023

ret = avahi_simple_poll_iterate(s, -1);

1377

2024

} else {

1378

if (debug){

2025

if(debug){

1379

2026

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

1380

2027

" it, or wait\n");

1381

2028

}

1398

2045

- ((intmax_t)waited_time.tv_sec * 1000))

1399

2046

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

1400

2047

1401

if (debug){

2048

if(debug){

1402

2049

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

1403

2050

block_time);

1404

2051

}

1426

2073

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

1427

2074

}

1428

2075

if(ret != 0){

1429

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

2076

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

1430

2077

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

1431

2078

}

1432

2079

}

1433

2080

}

1434

2081

}

1435

2082

1436

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

1437

error_t raise_privileges(void){

1438

error_t old_errno = errno;

1439

error_t ret_errno = 0;

1440

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

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1443

}

1444

errno = old_errno;

1445

return ret_errno;

1446

}

1447

1448

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

1449

error_t raise_privileges_permanently(void){

1450

error_t old_errno = errno;

1451

error_t ret_errno = raise_privileges();

1452

if(ret_errno != 0){

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

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

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1459

}

1460

errno = old_errno;

1461

return ret_errno;

1462

}

1463

1464

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

1465

error_t lower_privileges(void){

1466

error_t old_errno = errno;

1467

error_t ret_errno = 0;

1468

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

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1471

}

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

1476

/* Lower privileges permanently */

1477

error_t lower_privileges_permanently(void){

1478

error_t old_errno = errno;

1479

error_t ret_errno = 0;

1480

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

1481

ret_errno = errno;

1482

perror_plus("setuid");

1483

}

1484

errno = old_errno;

1485

return ret_errno;

1486

}

1487

1488

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

2083

__attribute__((nonnull))

2084

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

1489

2085

const float delay){

1490

struct dirent **direntries;

2086

struct dirent **direntries = NULL;

2087

if(hookdir_fd == -1){

2088

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2089

| O_CLOEXEC);

2090

if(hookdir_fd == -1){

2091

if(errno == ENOENT){

2092

if(debug){

2093

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

2094

" found\n", hookdir);

2095

}

2096

} else {

2097

perror_plus("open");

2098

}

2099

return;

2100

}

2101

}

2102

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

2103

if(devnull == -1){

2104

perror_plus("open(\"/dev/null\", O_RDONLY)");

2105

return;

2106

}

2107

int numhooks = scandirat(hookdir_fd, ".", &direntries,

2108

runnable_hook, alphasort);

2109

if(numhooks == -1){

2110

perror_plus("scandir");

2111

close(devnull);

2112

return;

2113

}

1491

2114

struct dirent *direntry;

1492

2115

int ret;

1493

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

1494

alphasort);

1495

if(numhooks == -1){

1496

if(errno == ENOENT){

1497

if(debug){

1498

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

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

2116

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

2117

direntry = direntries[i];

2118

if(debug){

2119

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

2120

direntry->d_name);

1503

2121

}

1504

} else {

1505

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

1506

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

1507

direntry = direntries[i];

1508

char *fullname = NULL;

1509

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

1510

if(ret < 0){

2122

pid_t hook_pid = fork();

2123

if(hook_pid == 0){

2124

/* Child */

2125

/* Raise privileges */

2126

errno = raise_privileges_permanently();

2127

if(errno != 0){

2128

perror_plus("Failed to raise privileges");

2129

_exit(EX_NOPERM);

2130

}

2131

/* Set group */

2132

errno = 0;

2133

ret = setgid(0);

2134

if(ret == -1){

2135

perror_plus("setgid");

2136

_exit(EX_NOPERM);

2137

}

2138

/* Reset supplementary groups */

2139

errno = 0;

2140

ret = setgroups(0, NULL);

2141

if(ret == -1){

2142

perror_plus("setgroups");

2143

_exit(EX_NOPERM);

2144

}

2145

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

2146

if(ret == -1){

2147

perror_plus("setenv");

2148

_exit(EX_OSERR);

2149

}

2150

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

2151

if(ret == -1){

2152

perror_plus("setenv");

2153

_exit(EX_OSERR);

2154

}

2155

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

2156

if(ret == -1){

2157

perror_plus("setenv");

2158

_exit(EX_OSERR);

2159

}

2160

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

2161

if(ret == -1){

2162

perror_plus("setenv");

2163

_exit(EX_OSERR);

2164

}

2165

char *delaystring;

2166

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

2167

if(ret == -1){

1511

2168

perror_plus("asprintf");

1512

continue;

1513

}

1514

if(debug){

1515

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

1516

direntry->d_name);

1517

}

1518

pid_t hook_pid = fork();

1519

if(hook_pid == 0){

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1535

dup2(devnull, STDIN_FILENO);

1536

close(devnull);

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1538

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

1539

if(ret == -1){

1540

perror_plus("setenv");

1541

_exit(EX_OSERR);

1542

}

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

char *delaystring;

1559

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

1560

if(ret == -1){

1561

perror_plus("asprintf");

1562

_exit(EX_OSERR);

1563

}

1564

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

1565

if(ret == -1){

1566

free(delaystring);

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

if(ret == -1){

1570

2173

free(delaystring);

1571

if(connect_to != NULL){

1572

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

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

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

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

2174

perror_plus("setenv");

2175

_exit(EX_OSERR);

2176

}

2177

free(delaystring);

2178

if(connect_to != NULL){

2179

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

2180

if(ret == -1){

2181

perror_plus("setenv");

2182

_exit(EX_OSERR);

2183

}

2184

}

2185

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

2186

direntry->d_name,

2187

O_RDONLY));

2188

if(hook_fd == -1){

2189

perror_plus("openat");

2190

_exit(EXIT_FAILURE);

2191

}

2192

if(close(hookdir_fd) == -1){

2193

perror_plus("close");

2194

_exit(EXIT_FAILURE);

2195

}

2196

ret = dup2(devnull, STDIN_FILENO);

2197

if(ret == -1){

2198

perror_plus("dup2(devnull, STDIN_FILENO)");

2199

_exit(EX_OSERR);

2200

}

2201

ret = close(devnull);

2202

if(ret == -1){

2203

perror_plus("close");

2204

_exit(EX_OSERR);

2205

}

2206

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2207

if(ret == -1){

2208

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

2209

_exit(EX_OSERR);

2210

}

2211

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

2212

environ) == -1){

2213

perror_plus("fexecve");

2214

_exit(EXIT_FAILURE);

2215

}

2216

} else {

2217

if(hook_pid == -1){

2218

perror_plus("fork");

2219

free(direntry);

2220

continue;

2221

}

2222

int status;

2223

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

2224

perror_plus("waitpid");

2225

free(direntry);

2226

continue;

2227

}

2228

if(WIFEXITED(status)){

2229

if(WEXITSTATUS(status) != 0){

2230

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

2231

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

2232

WEXITSTATUS(status));

2233

free(direntry);

2234

continue;

2235

}

2236

} else if(WIFSIGNALED(status)){

2237

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

2238

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

2239

WTERMSIG(status));

2240

free(direntry);

2241

continue;

1582

2242

} else {

1583

int status;

1584

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

1585

perror_plus("waitpid");

1586

free(fullname);

1587

continue;

1588

}

1589

if(WIFEXITED(status)){

1590

if(WEXITSTATUS(status) != 0){

1591

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

1592

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

1593

WEXITSTATUS(status));

1594

free(fullname);

1595

continue;

1596

}

1597

} else if(WIFSIGNALED(status)){

1598

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

1599

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

1600

WTERMSIG(status));

1601

free(fullname);

1602

continue;

1603

} else {

1604

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

1605

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

1606

free(fullname);

1607

continue;

1608

}

1609

}

1610

free(fullname);

1611

if(debug){

1612

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

1613

direntry->d_name);

1614

}

1615

}

1616

close(devnull);

1617

}

1618

return true;

2243

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

2244

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

2245

free(direntry);

2246

continue;

2247

}

2248

}

2249

if(debug){

2250

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

2251

direntry->d_name);

2252

}

2253

free(direntry);

2254

}

2255

free(direntries);

2256

if(close(hookdir_fd) == -1){

2257

perror_plus("close");

2258

} else {

2259

hookdir_fd = -1;

2260

}

2261

close(devnull);

1619

2262

}

1620

2263

1621

error_t bring_up_interface(const char *const interface,

1622

const float delay){

1623

int sd = -1;

1624

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

2264

__attribute__((nonnull, warn_unused_result))

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

2268

int ret;

1627

2269

struct ifreq network;

1628

2270

unsigned int if_index = if_nametoindex(interface);

1629

2271

if(if_index == 0){

1638

2280

}

1639

2281

1640

2282

if(not interface_is_up(interface)){

1641

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

2283

int ret_errno = 0;

2284

int ioctl_errno = 0;

2285

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

1642

2286

ret_errno = errno;

1643

2287

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

1644

2288

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

2289

errno = old_errno;

1645

2290

return ret_errno;

1646

2291

}

1647

network.ifr_flags |= IFF_UP;

2292

network.ifr_flags |= IFF_UP; /* set flag */

1648

2293

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

2294

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

2295

if(sd == -1){

1651

2296

ret_errno = errno;

1652

2297

perror_plus("socket");

1653

2298

errno = old_errno;

1654

2299

return ret_errno;

1655

2300

}

1656

2301

1657

2302

if(quit_now){

1658

close(sd);

2303

ret = close(sd);

2304

if(ret == -1){

2305

perror_plus("close");

2306

}

1659

2307

errno = old_errno;

1660

2308

return EINTR;

1661

2309

}

1665

2313

interface);

1666

2314

}

1667

2315

1668

/* Raise priviliges */

1669

raise_privileges();

2316

/* Raise privileges */

2317

ret_errno = raise_privileges();

2318

if(ret_errno != 0){

2319

errno = ret_errno;

2320

perror_plus("Failed to raise privileges");

2321

}

1670

2322

1671

2323

#ifdef __linux__

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

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

1674

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

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

2324

int ret_linux;

2325

bool restore_loglevel = false;

2326

if(ret_errno == 0){

2327

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2328

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

2329

ret_linux = klogctl(8, NULL, 5);

2330

if(ret_linux == -1){

2331

perror_plus("klogctl");

2332

} else {

2333

restore_loglevel = true;

2334

}

1679

2335

}

1680

2336

#endif /* __linux__ */

1681

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

1682

ret_errno = errno;

2337

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

2338

ioctl_errno = errno;

1683

2339

#ifdef __linux__

1684

2340

if(restore_loglevel){

1685

2341

ret_linux = klogctl(7, NULL, 0);

1689

2345

}

1690

2346

#endif /* __linux__ */

1691

2347

1692

/* Lower privileges */

1693

lower_privileges();

2348

/* If raise_privileges() succeeded above */

2349

if(ret_errno == 0){

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

1694

2357

1695

2358

/* Close the socket */

1696

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

2359

ret = close(sd);

1697

2360

if(ret == -1){

1698

2361

perror_plus("close");

1699

2362

}

1700

2363

1701

2364

if(ret_setflags == -1){

1702

errno = ret_errno;

2365

errno = ioctl_errno;

1703

2366

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

2367

errno = old_errno;

1705

return ret_errno;

2368

return ioctl_errno;

1706

2369

}

1707

2370

} else if(debug){

1708

2371

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

1711

2374

1712

2375

/* Sleep checking until interface is running.

1713

2376

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

1714

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

2377

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

1715

2378

if(interface_is_running(interface)){

1716

2379

break;

1717

2380

}

1726

2389

return 0;

1727

2390

}

1728

2391

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

2392

__attribute__((nonnull, warn_unused_result))

2393

int take_down_interface(const char *const interface){

2394

int old_errno = errno;

1734

2395

struct ifreq network;

1735

2396

unsigned int if_index = if_nametoindex(interface);

1736

2397

if(if_index == 0){

1739

2400

return ENXIO;

1740

2401

}

1741

2402

if(interface_is_up(interface)){

2403

int ret_errno = 0;

2404

int ioctl_errno = 0;

1742

2405

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

1743

2406

ret_errno = errno;

1744

2407

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

1745

2408

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

2409

errno = old_errno;

1746

2410

return ret_errno;

1747

2411

}

1748

2412

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

1749

2413

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

2414

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

2415

if(sd == -1){

1752

2416

ret_errno = errno;

1753

2417

perror_plus("socket");

1754

2418

errno = old_errno;

1760

2424

interface);

1761

2425

}

1762

2426

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

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

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

2427

/* Raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

}

2433

2434

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

2435

ioctl_errno = errno;

2436

2437

/* If raise_privileges() succeeded above */

2438

if(ret_errno == 0){

2439

/* Lower privileges */

2440

ret_errno = lower_privileges();

2441

if(ret_errno != 0){

2442

errno = ret_errno;

2443

perror_plus("Failed to lower privileges");

2444

}

2445

}

1771

2446

1772

2447

/* Close the socket */

1773

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

2448

int ret = close(sd);

1774

2449

if(ret == -1){

1775

2450

perror_plus("close");

1776

2451

}

1777

2452

1778

2453

if(ret_setflags == -1){

1779

errno = ret_errno;

2454

errno = ioctl_errno;

1780

2455

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

2456

errno = old_errno;

1782

return ret_errno;

2457

return ioctl_errno;

1783

2458

}

1784

2459

} else if(debug){

1785

2460

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

1791

2466

}

1792

2467

1793

2468

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

1794

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

1795

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

1796

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

1797

.interfaces = NULL, .interfaces_size = 0 };

2469

mandos_context mc = { .server = NULL, .dh_bits = 0,

2470

#if GNUTLS_VERSION_NUMBER >= 0x030606

2471

.priority = "SECURE128:!CTYPE-X.509"

2472

":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"

2473

":%PROFILE_ULTRA",

2474

#elif GNUTLS_VERSION_NUMBER < 0x030600

2475

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

2476

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2477

#else

2478

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

2479

#endif

2480

.current_server = NULL, .interfaces = NULL,

2481

.interfaces_size = 0 };

1798

2482

AvahiSServiceBrowser *sb = NULL;

1799

2483

error_t ret_errno;

1800

2484

int ret;

1803

2487

int exitcode = EXIT_SUCCESS;

1804

2488

char *interfaces_to_take_down = NULL;

1805

2489

size_t interfaces_to_take_down_size = 0;

1806

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

1807

bool tempdir_created = false;

2490

char run_tempdir[] = "/run/tmp/mandosXXXXXX";

2491

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

2492

char *tempdir = NULL;

1808

2493

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1809

2494

const char *seckey = PATHDIR "/" SECKEY;

1810

2495

const char *pubkey = PATHDIR "/" PUBKEY;

2496

#if GNUTLS_VERSION_NUMBER >= 0x030606

2497

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2498

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2499

#endif

2500

const char *dh_params_file = NULL;

1811

2501

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1813

2502

1814

2503

bool gnutls_initialized = false;

1815

2504

bool gpgme_initialized = false;

1861

2550

{ .name = "pubkey", .key = 'p',

1862

2551

.arg = "FILE",

1863

2552

.doc = "OpenPGP public key file base name",

1864

.group = 2 },

2553

.group = 1 },

2554

{ .name = "tls-privkey", .key = 't',

2555

.arg = "FILE",

2556

#if GNUTLS_VERSION_NUMBER >= 0x030606

2557

.doc = "TLS private key file base name",

2558

#else

2559

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2560

#endif

2561

.group = 1 },

2562

{ .name = "tls-pubkey", .key = 'T',

2563

.arg = "FILE",

2564

#if GNUTLS_VERSION_NUMBER >= 0x030606

2565

.doc = "TLS public key file base name",

2566

#else

2567

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2568

#endif

2569

.group = 1 },

1865

2570

{ .name = "dh-bits", .key = 129,

1866

2571

.arg = "BITS",

1867

2572

.doc = "Bit length of the prime number used in the"

1868

2573

" Diffie-Hellman key exchange",

1869

2574

.group = 2 },

2575

{ .name = "dh-params", .key = 134,

2576

.arg = "FILE",

2577

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2578

" for the Diffie-Hellman key exchange",

2579

.group = 2 },

1870

2580

{ .name = "priority", .key = 130,

1871

2581

.arg = "STRING",

1872

2582

.doc = "GnuTLS priority string for the TLS handshake",

1918

2628

case 'p': /* --pubkey */

1919

2629

pubkey = arg;

1920

2630

break;

2631

case 't': /* --tls-privkey */

2632

#if GNUTLS_VERSION_NUMBER >= 0x030606

2633

tls_privkey = arg;

2634

#endif

2635

break;

2636

case 'T': /* --tls-pubkey */

2637

#if GNUTLS_VERSION_NUMBER >= 0x030606

2638

tls_pubkey = arg;

2639

#endif

2640

break;

1921

2641

case 129: /* --dh-bits */

1922

2642

errno = 0;

1923

2643

tmpmax = strtoimax(arg, &tmp, 10);

1927

2647

}

1928

2648

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

1929

2649

break;

2650

case 134: /* --dh-params */

2651

dh_params_file = arg;

2652

break;

1930

2653

case 130: /* --priority */

1931

2654

mc.priority = arg;

1932

2655

break;

1955

2678

argp_state_help(state, state->out_stream,

1956

2679

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1957

2680

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

1958

2682

case -3: /* --usage */

1959

2683

argp_state_help(state, state->out_stream,

1960

2684

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

1961

2686

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

1962

2687

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

1963

2688

exit(argp_err_exit_status);

1972

2697

.args_doc = "",

1973

2698

.doc = "Mandos client -- Get and decrypt"

1974

2699

" passwords from a Mandos server" };

1975

ret = argp_parse(&argp, argc, argv,

1976

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1977

switch(ret){

2700

ret_errno = argp_parse(&argp, argc, argv,

2701

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2702

switch(ret_errno){

1978

2703

case 0:

1979

2704

break;

1980

2705

case ENOMEM:

1981

2706

default:

1982

errno = ret;

2707

errno = ret_errno;

1983

2708

perror_plus("argp_parse");

1984

2709

exitcode = EX_OSERR;

1985

2710

goto end;

1988

2713

goto end;

1989

2714

}

1990

2715

}

1991

2716

1992

2717

{

1993

/* Work around Debian bug #633582:

1994

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

1995

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2718

/* Re-raise privileges */

2719

ret = raise_privileges();

2720

if(ret != 0){

2721

errno = ret;

2722

perror_plus("Failed to raise privileges");

2723

} else {

1998

2724

struct stat st;

1999

2725

2726

/* Work around Debian bug #633582:

2727

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

2728

2000

2729

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

2001

2730

int seckey_fd = open(seckey, O_RDONLY);

2002

2731

if(seckey_fd == -1){

2014

2743

}

2015

2744

}

2016

2745

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2746

close(seckey_fd);

2018

2747

}

2019

2748

}

2020

2749

2021

2750

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

2022

2751

int pubkey_fd = open(pubkey, O_RDONLY);

2023

2752

if(pubkey_fd == -1){

2035

2764

}

2036

2765

}

2037

2766

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

2767

close(pubkey_fd);

2768

}

2769

}

2770

2771

if(dh_params_file != NULL

2772

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2773

int dhparams_fd = open(dh_params_file, O_RDONLY);

2774

if(dhparams_fd == -1){

2775

perror_plus("open");

2776

} else {

2777

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

2778

if(ret == -1){

2779

perror_plus("fstat");

2780

} else {

2781

if(S_ISREG(st.st_mode)

2782

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

2783

ret = fchown(dhparams_fd, uid, gid);

2784

if(ret == -1){

2785

perror_plus("fchown");

2786

}

2787

}

2788

}

2789

close(dhparams_fd);

2790

}

2791

}

2792

2793

/* Work around Debian bug #981302

2794

<https://bugs.debian.org/981302> */

2795

if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){

2796

ret = symlink("/proc/self/fd", "/dev/fd");

2797

if(ret == -1){

2798

perror_plus("Failed to create /dev/fd symlink");

2799

}

2800

}

2801

2042

2802

/* Lower privileges */

2043

lower_privileges();

2803

ret = lower_privileges();

2804

if(ret != 0){

2805

errno = ret;

2806

perror_plus("Failed to lower privileges");

2807

}

2044

2808

}

2045

2809

}

2046

2810

2070

2834

goto end;

2071

2835

}

2072

2836

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

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

2076

}

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2837

argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');

2838

}

2839

run_network_hooks("start", interfaces_hooks != NULL ?

2840

interfaces_hooks : "", delay);

2081

2841

}

2082

2842

2083

2843

if(not debug){

2161

2921

2162

2922

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

2163

2923

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2924

struct dirent **direntries = NULL;

2165

2925

/* Look for any good interfaces */

2166

2926

ret = scandir(sys_class_net, &direntries, good_interface,

2167

2927

alphasort);

2171

2931

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

2172

2932

direntries[i]->d_name);

2173

2933

if(ret_errno != 0){

2934

errno = ret_errno;

2174

2935

perror_plus("argz_add");

2936

free(direntries[i]);

2175

2937

continue;

2176

2938

}

2177

2939

if(debug){

2178

2940

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

2179

2941

direntries[i]->d_name);

2180

2942

}

2943

free(direntries[i]);

2181

2944

}

2182

2945

free(direntries);

2183

2946

} else {

2184

free(direntries);

2947

if(ret == 0){

2948

free(direntries);

2949

}

2185

2950

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

2186

2951

exitcode = EXIT_FAILURE;

2187

2952

goto end;

2210

2975

break;

2211

2976

}

2212

2977

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2978

errno = bring_up_interface(interface, delay);

2214

2979

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2217

perror_plus("Failed to bring up interface");

2980

if(errno != 0){

2981

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2982

" %s\n", interface, strerror(errno));

2218

2983

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2984

errno = argz_add(&interfaces_to_take_down,

2985

&interfaces_to_take_down_size,

2986

interface);

2987

if(errno != 0){

2988

perror_plus("argz_add");

2989

}

2222

2990

}

2223

2991

}

2224

2992

}

2240

3008

goto end;

2241

3009

}

2242

3010

2243

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

3011

#if GNUTLS_VERSION_NUMBER >= 0x030606

3012

ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);

3013

#elif GNUTLS_VERSION_NUMBER < 0x030600

3014

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

3015

#else

3016

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

3017

#endif

2244

3018

if(ret == -1){

2245

3019

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

2246

3020

exitcode = EX_UNAVAILABLE;

2253

3027

goto end;

2254

3028

}

2255

3029

2256

if(mkdtemp(tempdir) == NULL){

3030

/* Try /run/tmp before /tmp */

3031

tempdir = mkdtemp(run_tempdir);

3032

if(tempdir == NULL and errno == ENOENT){

3033

if(debug){

3034

fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",

3035

run_tempdir, old_tempdir);

3036

}

3037

tempdir = mkdtemp(old_tempdir);

3038

}

3039

if(tempdir == NULL){

2257

3040

perror_plus("mkdtemp");

2258

3041

goto end;

2259

3042

}

2260

tempdir_created = true;

2261

3043

2262

3044

if(quit_now){

2263

3045

goto end;

2338

3120

sleep((unsigned int)retry_interval);

2339

3121

}

2340

3122

2341

if (not quit_now){

3123

if(not quit_now){

2342

3124

exitcode = EXIT_SUCCESS;

2343

3125

}

2344

3126

2360

3142

2361

3143

/* Allocate a new server */

2362

3144

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2363

&config, NULL, NULL, &ret_errno);

3145

&config, NULL, NULL, &ret);

2364

3146

2365

3147

/* Free the Avahi configuration data */

2366

3148

avahi_server_config_free(&config);

2369

3151

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

2370

3152

if(mc.server == NULL){

2371

3153

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

2372

avahi_strerror(ret_errno));

3154

avahi_strerror(ret));

2373

3155

exitcode = EX_UNAVAILABLE;

2374

3156

goto end;

2375

3157

}

2399

3181

if(debug){

2400

3182

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

2401

3183

}

2402

3184

2403

3185

ret = avahi_loop_with_timeout(simple_poll,

2404

3186

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

2405

3187

if(debug){

2410

3192

end:

2411

3193

2412

3194

if(debug){

2413

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

3195

if(signal_received){

3196

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

3197

argv[0], signal_received,

3198

strsignal(signal_received));

3199

} else {

3200

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

3201

}

2414

3202

}

2415

3203

2416

3204

/* Cleanup things */

2427

3215

2428

3216

if(gnutls_initialized){

2429

3217

gnutls_certificate_free_credentials(mc.cred);

2430

gnutls_global_deinit();

2431

3218

gnutls_dh_params_deinit(mc.dh_params);

2432

3219

}

2433

3220

2441

3228

mc.current_server->prev->next = NULL;

2442

3229

while(mc.current_server != NULL){

2443

3230

server *next = mc.current_server->next;

3231

#ifdef __GNUC__

3232

#pragma GCC diagnostic push

3233

#pragma GCC diagnostic ignored "-Wcast-qual"

3234

#endif

3235

free((char *)(mc.current_server->ip));

3236

#ifdef __GNUC__

3237

#pragma GCC diagnostic pop

3238

#endif

2444

3239

free(mc.current_server);

2445

3240

mc.current_server = next;

2446

3241

}

2447

3242

}

2448

3243

2449

/* Re-raise priviliges */

3244

/* Re-raise privileges */

2450

3245

{

2451

raise_privileges();

2452

2453

/* Run network hooks */

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2456

2457

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

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

2467

}

2468

}

2469

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

2470

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

2471

" down\n");

2472

}

2473

}

2474

2475

lower_privileges_permanently();

3246

ret = raise_privileges();

3247

if(ret != 0){

3248

errno = ret;

3249

perror_plus("Failed to raise privileges");

3250

} else {

3251

3252

/* Run network hooks */

3253

run_network_hooks("stop", interfaces_hooks != NULL ?

3254

interfaces_hooks : "", delay);

3255

3256

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

3257

{

3258

char *interface = NULL;

3259

while((interface = argz_next(interfaces_to_take_down,

3260

interfaces_to_take_down_size,

3261

interface))){

3262

ret = take_down_interface(interface);

3263

if(ret != 0){

3264

errno = ret;

3265

perror_plus("Failed to take down interface");

3266

}

3267

}

3268

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

3269

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

3270

" down\n");

3271

}

3272

}

3273

}

3274

3275

ret = lower_privileges_permanently();

3276

if(ret != 0){

3277

errno = ret;

3278

perror_plus("Failed to lower privileges permanently");

3279

}

2476

3280

}

2477

3281

2478

3282

free(interfaces_to_take_down);

2479

3283

free(interfaces_hooks);

2480

3284

3285

void clean_dir_at(int base, const char * const dirname,

3286

uintmax_t level){

3287

struct dirent **direntries = NULL;

3288

int dret;

3289

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3290

O_RDONLY

3291

| O_NOFOLLOW

3292

| O_DIRECTORY

3293

| O_PATH));

3294

if(dir_fd == -1){

3295

perror_plus("open");

3296

return;

3297

}

3298

int numentries = scandirat(dir_fd, ".", &direntries,

3299

notdotentries, alphasort);

3300

if(numentries >= 0){

3301

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

3302

if(debug){

3303

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3304

dirname, direntries[i]->d_name);

3305

}

3306

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3307

if(dret == -1){

3308

if(errno == EISDIR){

3309

dret = unlinkat(dir_fd, direntries[i]->d_name,

3310

AT_REMOVEDIR);

3311

}

3312

if((dret == -1) and (errno == ENOTEMPTY)

3313

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3314

== 0) and (level == 0)){

3315

/* Recurse only in this special case */

3316

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3317

dret = 0;

3318

}

3319

if((dret == -1) and (errno != ENOENT)){

3320

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3321

direntries[i]->d_name, strerror(errno));

3322

}

3323

}

3324

free(direntries[i]);

3325

}

3326

3327

/* need to clean even if 0 because man page doesn't specify */

3328

free(direntries);

3329

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3330

if(dret == -1 and errno != ENOENT){

3331

perror_plus("rmdir");

3332

}

3333

} else {

3334

perror_plus("scandirat");

3335

}

3336

close(dir_fd);

3337

}

3338

2481

3339

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

2482

if(tempdir_created){

2483

struct dirent **direntries = NULL;

2484

struct dirent *direntry = NULL;

2485

int numentries = scandir(tempdir, &direntries, notdotentries,

2486

alphasort);

2487

if (numentries > 0){

2488

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

2489

direntry = direntries[i];

2490

char *fullname = NULL;

2491

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

2492

direntry->d_name);

2493

if(ret < 0){

2494

perror_plus("asprintf");

2495

continue;

2496

}

2497

ret = remove(fullname);

2498

if(ret == -1){

2499

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

2500

strerror(errno));

2501

}

2502

free(fullname);

2503

}

2504

}

2505

2506

/* need to clean even if 0 because man page doesn't specify */

2507

free(direntries);

2508

if (numentries == -1){

2509

perror_plus("scandir");

2510

}

2511

ret = rmdir(tempdir);

2512

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

2513

perror_plus("rmdir");

2514

}

3340

if(tempdir != NULL){

3341

clean_dir_at(-1, tempdir, 0);

2515

3342

}

2516

3343

2517

3344

if(quit_now){