/mandos/trunk : revision 1214

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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() */

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

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}

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/*

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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;

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(*current_server)->prev = new_server;

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}

239

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

240

if(ret == -1){

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perror_plus("clock_gettime");

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return false;

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}

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return true;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges(void){

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int old_errno = errno;

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int ret = 0;

288

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

289

ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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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){

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errno = old_errno;

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return ret;

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}

304

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

305

ret = errno;

306

}

307

errno = old_errno;

308

return ret;

309

}

310

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

312

__attribute__((warn_unused_result))

313

int lower_privileges(void){

314

int old_errno = errno;

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int ret = 0;

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if(seteuid(uid) == -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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}

322

323

/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

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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){

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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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}

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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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__attribute__((nonnull, warn_unused_result))

339

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){

252

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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.

257

348

*/

258

bool import_key(const char *filename){

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bool import_key(const char * const filename){

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int ret;

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int fd;

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352

gpgme_data_t pgp_data;

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return false;

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358

}

268

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

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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");

369

break;

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}

371

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

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break;

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}

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if(debug){

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

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}

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} else {

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if(debug){

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

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}

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}

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}

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struct stat keystat;

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ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

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break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

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break;

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}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

time_t keytime = keystat.st_mtim.tv_sec;

400

if(stime(&keytime) != 0){

401

perror_plus("stime");

402

}

403

ret = lower_privileges();

404

if(ret != 0){

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errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

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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

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

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420

gpgme_strsource(rc), gpgme_strerror(rc));

280

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return false;

281

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}

423

{

424

gpgme_import_result_t import_result

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= gpgme_op_import_result(mc->ctx);

426

if((import_result->imported < 1

427

or import_result->not_imported > 0)

428

and import_result->unchanged == 0){

429

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

430

fprintf_plus(stderr,

431

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

432

import_result->considered);

433

fprintf_plus(stderr,

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

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import_result->no_user_id);

436

fprintf_plus(stderr,

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

438

import_result->imported);

439

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

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import_result->imported_rsa);

441

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

442

import_result->unchanged);

443

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

444

import_result->new_user_ids);

445

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

446

import_result->new_sub_keys);

447

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

448

import_result->new_signatures);

449

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

450

import_result->new_revocations);

451

fprintf_plus(stderr,

452

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

453

import_result->secret_read);

454

fprintf_plus(stderr,

455

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

456

import_result->secret_imported);

457

fprintf_plus(stderr,

458

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

459

import_result->secret_unchanged);

460

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

461

import_result->not_imported);

462

for(gpgme_import_status_t import_status

463

= import_result->imports;

464

import_status != NULL;

465

import_status = import_status->next){

466

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

467

import_status->fpr);

468

if(import_status->result != GPG_ERR_NO_ERROR){

469

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

470

gpgme_strsource(import_status->result),

471

gpgme_strerror(import_status->result));

472

}

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_NEW

476

? "The key was new.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_UID

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SIG

484

? "The key contained new signatures.\n"

485

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

486

fprintf_plus(stderr,

487

import_status->status & GPGME_IMPORT_SUBKEY

488

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

489

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

490

fprintf_plus(stderr,

491

import_status->status & GPGME_IMPORT_SECRET

492

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

493

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

494

}

495

return false;

496

}

497

}

282

498

283

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

499

ret = close(fd);

284

500

if(ret == -1){

285

501

perror_plus("close");

286

502

}

325

541

/* Create new GPGME "context" */

326

542

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

327

543

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));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

331

546

return false;

332

547

}

333

548

342

557

* Decrypt OpenPGP data.

343

558

* Returns -1 on error

344

559

*/

560

__attribute__((nonnull, warn_unused_result))

345

561

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

562

size_t crypto_size,

347

563

char **plaintext,

368

584

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

369

585

rc = gpgme_data_new(&dh_plain);

370

586

if(rc != GPG_ERR_NO_ERROR){

371

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

372

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

587

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

373

588

gpgme_strsource(rc), gpgme_strerror(rc));

374

589

gpgme_data_release(dh_crypto);

375

590

return -1;

388

603

if(result == NULL){

389

604

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

390

605

} 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);

606

if(result->unsupported_algorithm != NULL) {

607

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

608

result->unsupported_algorithm);

609

}

610

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

611

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

395

612

if(result->file_name != NULL){

396

613

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

397

614

}

398

gpgme_recipient_t recipient;

399

recipient = result->recipients;

400

while(recipient != NULL){

615

616

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

617

r = r->next){

401

618

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);

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

405

621

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

408

recipient = recipient->next;

622

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

409

623

}

410

624

}

411

625

}

467

681

return plaintext_length;

468

682

}

469

683

470

static const char * safer_gnutls_strerror(int value){

684

__attribute__((warn_unused_result, const))

685

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

686

if(str == NULL)

687

return "(unknown)";

688

return str;

689

}

690

691

__attribute__((warn_unused_result))

692

static const char *safer_gnutls_strerror(int value){

471

693

const char *ret = gnutls_strerror(value);

472

if(ret == NULL)

473

ret = "(unknown)";

474

return ret;

694

return safe_string(ret);

475

695

}

476

696

477

697

/* GnuTLS log function callback */

698

__attribute__((nonnull))

478

699

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

479

700

const char* string){

480

701

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

481

702

}

482

703

704

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

483

705

static int init_gnutls_global(const char *pubkeyfilename,

484

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

485

708

mandos_context *mc){

486

709

int ret;

487

710

489

712

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

490

713

}

491

714

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

715

if(debug){

500

716

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

501

717

* - GnuTLS manual

509

725

if(ret != GNUTLS_E_SUCCESS){

510

726

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

511

727

safer_gnutls_strerror(ret));

512

gnutls_global_deinit();

513

728

return -1;

514

729

}

515

730

516

731

if(debug){

517

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

518

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

732

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

733

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

519

734

pubkeyfilename,

520

735

seckeyfilename);

521

736

}

522

737

738

#if GNUTLS_VERSION_NUMBER >= 0x030606

739

ret = gnutls_certificate_set_rawpk_key_file

740

(mc->cred, pubkeyfilename, seckeyfilename,

741

GNUTLS_X509_FMT_PEM, /* format */

742

NULL, /* pass */

743

/* key_usage */

744

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

745

NULL, /* names */

746

0, /* names_length */

747

/* privkey_flags */

748

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

749

0); /* pkcs11_flags */

750

#elif GNUTLS_VERSION_NUMBER < 0x030600

523

751

ret = gnutls_certificate_set_openpgp_key_file

524

752

(mc->cred, pubkeyfilename, seckeyfilename,

525

753

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

526

757

if(ret != GNUTLS_E_SUCCESS){

527

758

fprintf_plus(stderr,

528

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

759

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

529

760

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

530

761

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

531

762

safer_gnutls_strerror(ret));

540

771

safer_gnutls_strerror(ret));

541

772

goto globalfail;

542

773

}

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);

774

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

775

if(dhparamsfilename != NULL){

776

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

777

do {

778

int dhpfile = open(dhparamsfilename, O_RDONLY);

779

if(dhpfile == -1){

780

perror_plus("open");

781

dhparamsfilename = NULL;

782

break;

783

}

784

size_t params_capacity = 0;

785

while(true){

786

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

787

(size_t)params.size,

788

(size_t)params_capacity);

789

if(params_capacity == 0){

790

perror_plus("incbuffer");

791

free(params.data);

792

params.data = NULL;

793

dhparamsfilename = NULL;

794

break;

795

}

796

ssize_t bytes_read = read(dhpfile,

797

params.data + params.size,

798

BUFFER_SIZE);

799

/* EOF */

800

if(bytes_read == 0){

801

break;

802

}

803

/* check bytes_read for failure */

804

if(bytes_read < 0){

805

perror_plus("read");

806

free(params.data);

807

params.data = NULL;

808

dhparamsfilename = NULL;

809

break;

810

}

811

params.size += (unsigned int)bytes_read;

812

}

813

ret = close(dhpfile);

814

if(ret == -1){

815

perror_plus("close");

816

}

817

if(params.data == NULL){

818

dhparamsfilename = NULL;

819

}

820

if(dhparamsfilename == NULL){

821

break;

822

}

823

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

824

GNUTLS_X509_FMT_PEM);

825

if(ret != GNUTLS_E_SUCCESS){

826

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

827

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

828

safer_gnutls_strerror(ret));

829

dhparamsfilename = NULL;

830

}

831

free(params.data);

832

} while(false);

833

}

834

if(dhparamsfilename == NULL){

835

if(mc->dh_bits == 0){

836

#if GNUTLS_VERSION_NUMBER < 0x030600

837

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

838

/* Try to read the private key file */

839

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

840

do {

841

int secfile = open(seckeyfilename, O_RDONLY);

842

if(secfile == -1){

843

perror_plus("open");

844

break;

845

}

846

size_t buffer_capacity = 0;

847

while(true){

848

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

849

(size_t)buffer.size,

850

(size_t)buffer_capacity);

851

if(buffer_capacity == 0){

852

perror_plus("incbuffer");

853

free(buffer.data);

854

buffer.data = NULL;

855

break;

856

}

857

ssize_t bytes_read = read(secfile,

858

buffer.data + buffer.size,

859

BUFFER_SIZE);

860

/* EOF */

861

if(bytes_read == 0){

862

break;

863

}

864

/* check bytes_read for failure */

865

if(bytes_read < 0){

866

perror_plus("read");

867

free(buffer.data);

868

buffer.data = NULL;

869

break;

870

}

871

buffer.size += (unsigned int)bytes_read;

872

}

873

close(secfile);

874

} while(false);

875

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

876

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

877

if(buffer.data != NULL){

878

{

879

gnutls_openpgp_privkey_t privkey = NULL;

880

ret = gnutls_openpgp_privkey_init(&privkey);

881

if(ret != GNUTLS_E_SUCCESS){

882

fprintf_plus(stderr, "Error initializing OpenPGP key"

883

" structure: %s",

884

safer_gnutls_strerror(ret));

885

free(buffer.data);

886

buffer.data = NULL;

887

} else {

888

ret = gnutls_openpgp_privkey_import

889

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

890

if(ret != GNUTLS_E_SUCCESS){

891

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

892

safer_gnutls_strerror(ret));

893

privkey = NULL;

894

}

895

free(buffer.data);

896

buffer.data = NULL;

897

if(privkey != NULL){

898

/* Use private key to suggest an appropriate

899

sec_param */

900

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

901

gnutls_openpgp_privkey_deinit(privkey);

902

if(debug){

903

fprintf_plus(stderr, "This OpenPGP key implies using"

904

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

905

safe_string(gnutls_sec_param_get_name

906

(sec_param)));

907

}

908

}

909

}

910

}

911

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

912

/* Err on the side of caution */

913

sec_param = GNUTLS_SEC_PARAM_ULTRA;

914

if(debug){

915

fprintf_plus(stderr, "Falling back to security parameter"

916

" \"%s\"\n",

917

safe_string(gnutls_sec_param_get_name

918

(sec_param)));

919

}

920

}

921

}

922

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

923

if(uret != 0){

924

mc->dh_bits = uret;

925

if(debug){

926

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

927

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

928

safe_string(gnutls_sec_param_get_name

929

(sec_param)),

930

mc->dh_bits);

931

}

932

} else {

933

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

934

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

935

safe_string(gnutls_sec_param_get_name

936

(sec_param)),

937

safer_gnutls_strerror(ret));

938

goto globalfail;

939

}

940

#endif

941

} else { /* dh_bits != 0 */

942

if(debug){

943

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

944

mc->dh_bits);

945

}

946

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

947

if(ret != GNUTLS_E_SUCCESS){

948

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

949

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

950

safer_gnutls_strerror(ret));

951

goto globalfail;

952

}

953

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

954

}

955

}

551

956

552

957

return 0;

553

958

554

959

globalfail:

555

960

556

961

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_global_deinit();

558

962

gnutls_dh_params_deinit(mc->dh_params);

559

963

return -1;

560

964

}

561

965

966

__attribute__((nonnull, warn_unused_result))

562

967

static int init_gnutls_session(gnutls_session_t *session,

563

968

mandos_context *mc){

564

969

int ret;

565

970

/* GnuTLS session creation */

566

971

do {

567

ret = gnutls_init(session, GNUTLS_SERVER);

972

ret = gnutls_init(session, (GNUTLS_SERVER

973

#if GNUTLS_VERSION_NUMBER >= 0x030506

974

| GNUTLS_NO_TICKETS

975

#endif

976

#if GNUTLS_VERSION_NUMBER >= 0x030606

977

| GNUTLS_ENABLE_RAWPK

978

#endif

979

));

568

980

if(quit_now){

569

981

return -1;

570

982

}

611

1023

/* ignore client certificate if any. */

612

1024

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

1025

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

615

616

1026

return 0;

617

1027

}

618

1028

620

1030

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

621

1031

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

622

1032

1033

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

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool add_delete_local_route(const bool add,

1036

const char *address,

1037

AvahiIfIndex if_index){

1038

int ret;

1039

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

1040

char add_arg[] = "add";

1041

char delete_arg[] = "delete";

1042

char debug_flag[] = "--debug";

1043

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1044

if(pluginhelperdir == NULL){

1045

if(debug){

1046

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1047

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

1048

}

1049

return false;

1050

}

1051

1052

char interface[IF_NAMESIZE];

1053

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

1054

perror_plus("if_indextoname");

1055

return false;

1056

}

1057

1058

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

1059

if(devnull == -1){

1060

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

1061

return false;

1062

}

1063

pid_t pid = fork();

1064

if(pid == 0){

1065

/* Child */

1066

/* Raise privileges */

1067

errno = raise_privileges_permanently();

1068

if(errno != 0){

1069

perror_plus("Failed to raise privileges");

1070

/* _exit(EX_NOPERM); */

1071

} else {

1072

/* Set group */

1073

errno = 0;

1074

ret = setgid(0);

1075

if(ret == -1){

1076

perror_plus("setgid");

1077

close(devnull);

1078

_exit(EX_NOPERM);

1079

}

1080

/* Reset supplementary groups */

1081

errno = 0;

1082

ret = setgroups(0, NULL);

1083

if(ret == -1){

1084

perror_plus("setgroups");

1085

close(devnull);

1086

_exit(EX_NOPERM);

1087

}

1088

}

1089

ret = dup2(devnull, STDIN_FILENO);

1090

if(ret == -1){

1091

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

1092

close(devnull);

1093

_exit(EX_OSERR);

1094

}

1095

ret = close(devnull);

1096

if(ret == -1){

1097

perror_plus("close");

1098

}

1099

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1100

if(ret == -1){

1101

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

1102

_exit(EX_OSERR);

1103

}

1104

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

1105

O_RDONLY

1106

| O_DIRECTORY

1107

| O_PATH

1108

| O_CLOEXEC));

1109

if(helperdir_fd == -1){

1110

perror_plus("open");

1111

_exit(EX_UNAVAILABLE);

1112

}

1113

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

1114

helper, O_RDONLY));

1115

if(helper_fd == -1){

1116

perror_plus("openat");

1117

close(helperdir_fd);

1118

_exit(EX_UNAVAILABLE);

1119

}

1120

close(helperdir_fd);

1121

#ifdef __GNUC__

1122

#pragma GCC diagnostic push

1123

#pragma GCC diagnostic ignored "-Wcast-qual"

1124

#endif

1125

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

1126

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

1127

interface, debug ? debug_flag : NULL, NULL },

1128

environ) == -1){

1129

#ifdef __GNUC__

1130

#pragma GCC diagnostic pop

1131

#endif

1132

perror_plus("fexecve");

1133

_exit(EXIT_FAILURE);

1134

}

1135

}

1136

if(pid == -1){

1137

perror_plus("fork");

1138

close(devnull);

1139

return false;

1140

}

1141

ret = close(devnull);

1142

if(ret == -1){

1143

perror_plus("close");

1144

}

1145

int status;

1146

pid_t pret = -1;

1147

errno = 0;

1148

do {

1149

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

1150

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

1151

int errno_raising = 0;

1152

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

1153

errno_raising = errno;

1154

perror_plus("Failed to raise privileges in order to"

1155

" kill helper program");

1156

}

1157

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

1158

perror_plus("kill");

1159

}

1160

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

1161

perror_plus("Failed to lower privileges after killing"

1162

" helper program");

1163

}

1164

return false;

1165

}

1166

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

1167

if(pret == -1){

1168

perror_plus("waitpid");

1169

return false;

1170

}

1171

if(WIFEXITED(status)){

1172

if(WEXITSTATUS(status) != 0){

1173

fprintf_plus(stderr, "Error: iprouteadddel exited"

1174

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

1175

return false;

1176

}

1177

return true;

1178

}

1179

if(WIFSIGNALED(status)){

1180

fprintf_plus(stderr, "Error: iprouteadddel died by"

1181

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

1182

return false;

1183

}

1184

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

1185

return false;

1186

}

1187

1188

__attribute__((nonnull, warn_unused_result))

1189

static bool add_local_route(const char *address,

1190

AvahiIfIndex if_index){

1191

if(debug){

1192

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

1193

}

1194

return add_delete_local_route(true, address, if_index);

1195

}

1196

1197

__attribute__((nonnull, warn_unused_result))

1198

static bool delete_local_route(const char *address,

1199

AvahiIfIndex if_index){

1200

if(debug){

1201

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

1202

}

1203

return add_delete_local_route(false, address, if_index);

1204

}

1205

623

1206

/* Called when a Mandos server is found */

1207

__attribute__((nonnull, warn_unused_result))

624

1208

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

625

1209

AvahiIfIndex if_index,

626

1210

int af, mandos_context *mc){

627

1211

int ret, tcp_sd = -1;

628

1212

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1213

struct sockaddr_storage to;

633

1214

char *buffer = NULL;

634

1215

char *decrypted_buffer = NULL;

635

1216

size_t buffer_length = 0;

638

1219

int retval = -1;

639

1220

gnutls_session_t session;

640

1221

int pf; /* Protocol family */

1222

bool route_added = false;

641

1223

642

1224

errno = 0;

643

1225

665

1247

bool match = false;

666

1248

{

667

1249

char *interface = NULL;

668

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

669

interface))){

1250

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

1251

mc->interfaces_size,

1252

interface))){

670

1253

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

671

1254

match = true;

672

1255

break;

701

1284

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

702

1285

}

703

1286

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

1287

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

705

1288

if(tcp_sd < 0){

706

1289

int e = errno;

707

1290

perror_plus("socket");

714

1297

goto mandos_end;

715

1298

}

716

1299

717

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

718

1300

if(af == AF_INET6){

719

to.in6.sin6_family = (sa_family_t)af;

720

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

1301

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

1302

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

1303

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

721

1304

} else { /* IPv4 */

722

to.in.sin_family = (sa_family_t)af;

723

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

1305

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

1306

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

1307

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

724

1308

}

725

1309

if(ret < 0 ){

726

1310

int e = errno;

735

1319

goto mandos_end;

736

1320

}

737

1321

if(af == AF_INET6){

738

to.in6.sin6_port = htons(port);

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

740

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

741

-Wunreachable-code*/

1322

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

1323

if(IN6_IS_ADDR_LINKLOCAL

1324

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

742

1325

if(if_index == AVAHI_IF_UNSPEC){

743

1326

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

744

1327

" incomplete without a network interface\n");

746

1329

goto mandos_end;

747

1330

}

748

1331

/* Set the network interface number as scope */

749

to.in6.sin6_scope_id = (uint32_t)if_index;

1332

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

750

1333

}

751

1334

} else {

752

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

753

-Wconversion and

754

-Wunreachable-code */

1335

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

755

1336

}

756

1337

757

1338

if(quit_now){

774

1355

}

775

1356

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

776

1357

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

777

const char *pcret;

778

if(af == AF_INET6){

779

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

780

sizeof(addrstr));

781

} else {

782

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

783

sizeof(addrstr));

784

}

785

if(pcret == NULL){

786

perror_plus("inet_ntop");

787

} else {

788

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

789

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

790

}

791

}

792

}

793

794

if(quit_now){

795

errno = EINTR;

796

goto mandos_end;

797

}

798

799

if(af == AF_INET6){

800

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

801

} else {

802

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

803

}

804

if(ret < 0){

805

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

806

int e = errno;

807

perror_plus("connect");

808

errno = e;

809

}

810

goto mandos_end;

811

}

812

813

if(quit_now){

814

errno = EINTR;

815

goto mandos_end;

1358

if(af == AF_INET6){

1359

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

1360

sizeof(struct sockaddr_in6),

1361

addrstr, sizeof(addrstr), NULL, 0,

1362

NI_NUMERICHOST);

1363

} else {

1364

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

1365

sizeof(struct sockaddr_in),

1366

addrstr, sizeof(addrstr), NULL, 0,

1367

NI_NUMERICHOST);

1368

}

1369

if(ret == EAI_SYSTEM){

1370

perror_plus("getnameinfo");

1371

} else if(ret != 0) {

1372

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

1373

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

1374

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

1375

}

1376

}

1377

1378

if(quit_now){

1379

errno = EINTR;

1380

goto mandos_end;

1381

}

1382

1383

while(true){

1384

if(af == AF_INET6){

1385

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

1386

sizeof(struct sockaddr_in6));

1387

} else {

1388

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

1389

sizeof(struct sockaddr_in));

1390

}

1391

if(ret < 0){

1392

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

1393

and if_index != AVAHI_IF_UNSPEC

1394

and connect_to == NULL

1395

and not route_added and

1396

((af == AF_INET6 and not

1397

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1398

&to)->sin6_addr)))

1399

or (af == AF_INET and

1400

/* Not a a IPv4LL address */

1401

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

1402

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

1403

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

1404

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

1405

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

1406

connect to a Mandos server announced by Avahi on a server

1407

host with a global address. Work around this by retrying

1408

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

1409

1410

Avahi bug reference:

1411

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

1412

https://bugs.debian.org/587961

1413

*/

1414

if(debug){

1415

fprintf_plus(stderr, "Mandos server unreachable, trying"

1416

" direct route\n");

1417

}

1418

int e = errno;

1419

route_added = add_local_route(ip, if_index);

1420

if(route_added){

1421

continue;

1422

}

1423

errno = e;

1424

}

1425

if(errno != ECONNREFUSED or debug){

1426

int e = errno;

1427

perror_plus("connect");

1428

errno = e;

1429

}

1430

goto mandos_end;

1431

}

1432

1433

if(quit_now){

1434

errno = EINTR;

1435

goto mandos_end;

1436

}

1437

break;

816

1438

}

817

1439

818

1440

const char *out = mandos_protocol_version;

972

1594

&decrypted_buffer, mc);

973

1595

if(decrypted_buffer_size >= 0){

974

1596

1597

clearerr(stdout);

975

1598

written = 0;

976

1599

while(written < (size_t) decrypted_buffer_size){

977

1600

if(quit_now){

993

1616

}

994

1617

written += (size_t)ret;

995

1618

}

1619

ret = fflush(stdout);

1620

if(ret != 0){

1621

int e = errno;

1622

if(debug){

1623

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

1624

strerror(errno));

1625

}

1626

errno = e;

1627

goto mandos_end;

1628

}

996

1629

retval = 0;

997

1630

}

998

1631

}

1001

1634

1002

1635

mandos_end:

1003

1636

{

1637

if(route_added){

1638

if(not delete_local_route(ip, if_index)){

1639

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

1640

" interface %d", ip, if_index);

1641

}

1642

}

1004

1643

int e = errno;

1005

1644

free(decrypted_buffer);

1006

1645

free(buffer);

1007

1646

if(tcp_sd >= 0){

1008

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

1647

ret = close(tcp_sd);

1009

1648

}

1010

1649

if(ret == -1){

1011

1650

if(e == 0){

1036

1675

AVAHI_GCC_UNUSED AvahiStringList *txt,

1037

1676

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1038

1677

flags,

1039

void* mc){

1678

void *mc){

1040

1679

if(r == NULL){

1041

1680

return;

1042

1681

}

1045

1684

timed out */

1046

1685

1047

1686

if(quit_now){

1687

avahi_s_service_resolver_free(r);

1048

1688

return;

1049

1689

}

1050

1690

1095

1735

const char *domain,

1096

1736

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1097

1737

flags,

1098

void* mc){

1738

void *mc){

1099

1739

if(b == NULL){

1100

1740

return;

1101

1741

}

1161

1801

errno = old_errno;

1162

1802

}

1163

1803

1804

__attribute__((nonnull, warn_unused_result))

1164

1805

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

1165

1806

int ret;

1166

error_t ret_errno;

1807

int old_errno;

1167

1808

1168

1809

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

1169

1810

if(s < 0){

1170

ret_errno = errno;

1811

old_errno = errno;

1171

1812

perror_plus("socket");

1172

errno = ret_errno;

1813

errno = old_errno;

1173

1814

return false;

1174

1815

}

1175

strcpy(ifr->ifr_name, ifname);

1816

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

1817

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

1176

1818

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1177

1819

if(ret == -1){

1178

1820

if(debug){

1179

ret_errno = errno;

1821

old_errno = errno;

1180

1822

perror_plus("ioctl SIOCGIFFLAGS");

1181

errno = ret_errno;

1823

errno = old_errno;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1182

1829

}

1183

1830

return false;

1184

1831

}

1832

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

1833

old_errno = errno;

1834

perror_plus("close");

1835

errno = old_errno;

1836

}

1185

1837

return true;

1186

1838

}

1187

1839

1840

__attribute__((nonnull, warn_unused_result))

1188

1841

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

1189

1842

1190

1843

/* Reject the loopback device */

1232

1885

* corresponds to an acceptable network device.

1233

1886

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

1234

1887

*/

1888

__attribute__((nonnull, warn_unused_result))

1235

1889

int good_interface(const struct dirent *if_entry){

1236

1890

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

1237

1891

return 0;

1255

1909

/*

1256

1910

* This function determines if a network interface is up.

1257

1911

*/

1912

__attribute__((nonnull, warn_unused_result))

1258

1913

bool interface_is_up(const char *interface){

1259

1914

struct ifreq ifr;

1260

1915

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

1271

1926

/*

1272

1927

* This function determines if a network interface is running

1273

1928

*/

1929

__attribute__((nonnull, warn_unused_result))

1274

1930

bool interface_is_running(const char *interface){

1275

1931

struct ifreq ifr;

1276

1932

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

1284

1940

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

1285

1941

}

1286

1942

1943

__attribute__((nonnull, pure, warn_unused_result))

1287

1944

int notdotentries(const struct dirent *direntry){

1288

1945

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

1289

1946

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

1296

1953

}

1297

1954

1298

1955

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

1956

__attribute__((nonnull, warn_unused_result))

1299

1957

int runnable_hook(const struct dirent *direntry){

1300

1958

int ret;

1301

1959

size_t sret;

1309

1967

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

1310

1968

"abcdefghijklmnopqrstuvwxyz"

1311

1969

"0123456789"

1312

"_-");

1970

"_.-");

1313

1971

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

1314

1972

/* Contains non-allowed characters */

1315

1973

if(debug){

1319

1977

return 0;

1320

1978

}

1321

1979

1322

char *fullname = NULL;

1323

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

1324

if(ret < 0){

1325

perror_plus("asprintf");

1326

return 0;

1327

}

1328

1329

ret = stat(fullname, &st);

1980

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

1330

1981

if(ret == -1){

1331

1982

if(debug){

1332

1983

perror_plus("Could not stat hook");

1356

2007

return 1;

1357

2008

}

1358

2009

2010

__attribute__((nonnull, warn_unused_result))

1359

2011

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

2012

mandos_context *mc){

1361

2013

int ret;

1365

2017

1366

2018

while(true){

1367

2019

if(mc->current_server == NULL){

1368

if (debug){

2020

if(debug){

1369

2021

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

1370

2022

" No timeout!\n");

1371

2023

}

1372

2024

ret = avahi_simple_poll_iterate(s, -1);

1373

2025

} else {

1374

if (debug){

2026

if(debug){

1375

2027

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

1376

2028

" it, or wait\n");

1377

2029

}

1394

2046

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

1395

2047

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

1396

2048

1397

if (debug){

2049

if(debug){

1398

2050

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

1399

2051

block_time);

1400

2052

}

1422

2074

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

1423

2075

}

1424

2076

if(ret != 0){

1425

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

2077

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

1426

2078

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

1427

2079

}

1428

2080

}

1429

2081

}

1430

2082

}

1431

2083

1432

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

1433

error_t raise_privileges(void){

1434

error_t old_errno = errno;

1435

error_t ret_errno = 0;

1436

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

1437

ret_errno = errno;

1438

perror_plus("seteuid");

1439

}

1440

errno = old_errno;

1441

return ret_errno;

1442

}

1443

1444

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

1445

error_t raise_privileges_permanently(void){

1446

error_t old_errno = errno;

1447

error_t ret_errno = raise_privileges();

1448

if(ret_errno != 0){

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

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

1453

ret_errno = errno;

1454

perror_plus("seteuid");

1455

}

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

1460

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

1461

error_t lower_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

/* Lower privileges permanently */

1473

error_t lower_privileges_permanently(void){

1474

error_t old_errno = errno;

1475

error_t ret_errno = 0;

1476

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

1477

ret_errno = errno;

1478

perror_plus("setuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

2084

__attribute__((nonnull))

2085

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

1485

2086

const float delay){

1486

struct dirent **direntries;

2087

struct dirent **direntries = NULL;

2088

if(hookdir_fd == -1){

2089

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2090

| O_CLOEXEC);

2091

if(hookdir_fd == -1){

2092

if(errno == ENOENT){

2093

if(debug){

2094

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

2095

" found\n", hookdir);

2096

}

2097

} else {

2098

perror_plus("open");

2099

}

2100

return;

2101

}

2102

}

2103

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

2104

if(devnull == -1){

2105

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

2106

return;

2107

}

2108

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

2109

runnable_hook, alphasort);

2110

if(numhooks == -1){

2111

perror_plus("scandir");

2112

close(devnull);

2113

return;

2114

}

1487

2115

struct dirent *direntry;

1488

2116

int ret;

1489

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

1490

alphasort);

1491

if(numhooks == -1){

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

2117

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

2118

direntry = direntries[i];

2119

if(debug){

2120

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

2121

direntry->d_name);

1499

2122

}

1500

} else {

1501

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

1502

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

1503

direntry = direntries[i];

1504

char *fullname = NULL;

1505

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

1506

if(ret < 0){

2123

pid_t hook_pid = fork();

2124

if(hook_pid == 0){

2125

/* Child */

2126

/* Raise privileges */

2127

errno = raise_privileges_permanently();

2128

if(errno != 0){

2129

perror_plus("Failed to raise privileges");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Set group */

2133

errno = 0;

2134

ret = setgid(0);

2135

if(ret == -1){

2136

perror_plus("setgid");

2137

_exit(EX_NOPERM);

2138

}

2139

/* Reset supplementary groups */

2140

errno = 0;

2141

ret = setgroups(0, NULL);

2142

if(ret == -1){

2143

perror_plus("setgroups");

2144

_exit(EX_NOPERM);

2145

}

2146

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

2147

if(ret == -1){

2148

perror_plus("setenv");

2149

_exit(EX_OSERR);

2150

}

2151

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

2152

if(ret == -1){

2153

perror_plus("setenv");

2154

_exit(EX_OSERR);

2155

}

2156

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

2157

if(ret == -1){

2158

perror_plus("setenv");

2159

_exit(EX_OSERR);

2160

}

2161

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

2162

if(ret == -1){

2163

perror_plus("setenv");

2164

_exit(EX_OSERR);

2165

}

2166

char *delaystring;

2167

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

2168

if(ret == -1){

1507

2169

perror_plus("asprintf");

1508

continue;

1509

}

1510

if(debug){

1511

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

1512

direntry->d_name);

1513

}

1514

pid_t hook_pid = fork();

1515

if(hook_pid == 0){

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1531

dup2(devnull, STDIN_FILENO);

1532

close(devnull);

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

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

1540

if(ret == -1){

1541

perror_plus("setenv");

1542

_exit(EX_OSERR);

1543

}

1544

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

1545

if(ret == -1){

1546

perror_plus("setenv");

1547

_exit(EX_OSERR);

1548

}

1549

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

1550

if(ret == -1){

1551

perror_plus("setenv");

1552

_exit(EX_OSERR);

1553

}

1554

char *delaystring;

1555

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

1556

if(ret == -1){

1557

perror_plus("asprintf");

1558

_exit(EX_OSERR);

1559

}

1560

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

1561

if(ret == -1){

1562

free(delaystring);

1563

perror_plus("setenv");

1564

_exit(EX_OSERR);

1565

}

2170

_exit(EX_OSERR);

2171

}

2172

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

2173

if(ret == -1){

1566

2174

free(delaystring);

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

free(delaystring);

2179

if(connect_to != NULL){

2180

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

2181

if(ret == -1){

2182

perror_plus("setenv");

2183

_exit(EX_OSERR);

2184

}

2185

}

2186

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

2187

direntry->d_name,

2188

O_RDONLY));

2189

if(hook_fd == -1){

2190

perror_plus("openat");

2191

_exit(EXIT_FAILURE);

2192

}

2193

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

2194

perror_plus("close");

2195

_exit(EXIT_FAILURE);

2196

}

2197

ret = dup2(devnull, STDIN_FILENO);

2198

if(ret == -1){

2199

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

2200

_exit(EX_OSERR);

2201

}

2202

ret = close(devnull);

2203

if(ret == -1){

2204

perror_plus("close");

2205

_exit(EX_OSERR);

2206

}

2207

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2208

if(ret == -1){

2209

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

2210

_exit(EX_OSERR);

2211

}

2212

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

2213

environ) == -1){

2214

perror_plus("fexecve");

2215

_exit(EXIT_FAILURE);

2216

}

2217

} else {

2218

if(hook_pid == -1){

2219

perror_plus("fork");

2220

free(direntry);

2221

continue;

2222

}

2223

int status;

2224

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

2225

perror_plus("waitpid");

2226

free(direntry);

2227

continue;

2228

}

2229

if(WIFEXITED(status)){

2230

if(WEXITSTATUS(status) != 0){

2231

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

2232

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

2233

WEXITSTATUS(status));

2234

free(direntry);

2235

continue;

2236

}

2237

} else if(WIFSIGNALED(status)){

2238

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

2239

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

2240

WTERMSIG(status));

2241

free(direntry);

2242

continue;

1578

2243

} else {

1579

int status;

1580

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

1581

perror_plus("waitpid");

1582

free(fullname);

1583

continue;

1584

}

1585

if(WIFEXITED(status)){

1586

if(WEXITSTATUS(status) != 0){

1587

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

1588

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

1589

WEXITSTATUS(status));

1590

free(fullname);

1591

continue;

1592

}

1593

} else if(WIFSIGNALED(status)){

1594

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

1595

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

1596

WTERMSIG(status));

1597

free(fullname);

1598

continue;

1599

} else {

1600

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

1601

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

1602

free(fullname);

1603

continue;

1604

}

1605

}

1606

free(fullname);

1607

if(debug){

1608

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

1609

direntry->d_name);

1610

}

1611

}

1612

close(devnull);

1613

}

1614

return true;

2244

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

2245

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

2246

free(direntry);

2247

continue;

2248

}

2249

}

2250

if(debug){

2251

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

2252

direntry->d_name);

2253

}

2254

free(direntry);

2255

}

2256

free(direntries);

2257

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

2258

perror_plus("close");

2259

} else {

2260

hookdir_fd = -1;

2261

}

2262

close(devnull);

1615

2263

}

1616

2264

1617

error_t bring_up_interface(const char *const interface,

1618

const float delay){

1619

int sd = -1;

1620

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

2265

__attribute__((nonnull, warn_unused_result))

2266

int bring_up_interface(const char *const interface,

2267

const float delay){

2268

int old_errno = errno;

2269

int ret;

1623

2270

struct ifreq network;

1624

2271

unsigned int if_index = if_nametoindex(interface);

1625

2272

if(if_index == 0){

1634

2281

}

1635

2282

1636

2283

if(not interface_is_up(interface)){

1637

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

2284

int ret_errno = 0;

2285

int ioctl_errno = 0;

2286

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

1638

2287

ret_errno = errno;

1639

2288

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

1640

2289

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

2290

errno = old_errno;

1641

2291

return ret_errno;

1642

2292

}

1643

network.ifr_flags |= IFF_UP;

2293

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

1644

2294

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

2295

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

2296

if(sd == -1){

1647

2297

ret_errno = errno;

1648

2298

perror_plus("socket");

1649

2299

errno = old_errno;

1650

2300

return ret_errno;

1651

2301

}

1652

2302

1653

2303

if(quit_now){

1654

close(sd);

2304

ret = close(sd);

2305

if(ret == -1){

2306

perror_plus("close");

2307

}

1655

2308

errno = old_errno;

1656

2309

return EINTR;

1657

2310

}

1661

2314

interface);

1662

2315

}

1663

2316

1664

/* Raise priviliges */

1665

raise_privileges();

2317

/* Raise privileges */

2318

ret_errno = raise_privileges();

2319

if(ret_errno != 0){

2320

errno = ret_errno;

2321

perror_plus("Failed to raise privileges");

2322

}

1666

2323

1667

2324

#ifdef __linux__

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

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

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

2325

int ret_linux;

2326

bool restore_loglevel = false;

2327

if(ret_errno == 0){

2328

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2329

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

2330

ret_linux = klogctl(8, NULL, 5);

2331

if(ret_linux == -1){

2332

perror_plus("klogctl");

2333

} else {

2334

restore_loglevel = true;

2335

}

1675

2336

}

1676

2337

#endif /* __linux__ */

1677

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

1678

ret_errno = errno;

2338

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

2339

ioctl_errno = errno;

1679

2340

#ifdef __linux__

1680

2341

if(restore_loglevel){

1681

2342

ret_linux = klogctl(7, NULL, 0);

1685

2346

}

1686

2347

#endif /* __linux__ */

1687

2348

1688

/* Lower privileges */

1689

lower_privileges();

2349

/* If raise_privileges() succeeded above */

2350

if(ret_errno == 0){

2351

/* Lower privileges */

2352

ret_errno = lower_privileges();

2353

if(ret_errno != 0){

2354

errno = ret_errno;

2355

perror_plus("Failed to lower privileges");

2356

}

2357

}

1690

2358

1691

2359

/* Close the socket */

1692

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

2360

ret = close(sd);

1693

2361

if(ret == -1){

1694

2362

perror_plus("close");

1695

2363

}

1696

2364

1697

2365

if(ret_setflags == -1){

1698

errno = ret_errno;

2366

errno = ioctl_errno;

1699

2367

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1700

2368

errno = old_errno;

1701

return ret_errno;

2369

return ioctl_errno;

1702

2370

}

1703

2371

} else if(debug){

1704

2372

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

1707

2375

1708

2376

/* Sleep checking until interface is running.

1709

2377

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

1710

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

2378

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

1711

2379

if(interface_is_running(interface)){

1712

2380

break;

1713

2381

}

1722

2390

return 0;

1723

2391

}

1724

2392

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

2393

__attribute__((nonnull, warn_unused_result))

2394

int take_down_interface(const char *const interface){

2395

int old_errno = errno;

1730

2396

struct ifreq network;

1731

2397

unsigned int if_index = if_nametoindex(interface);

1732

2398

if(if_index == 0){

1735

2401

return ENXIO;

1736

2402

}

1737

2403

if(interface_is_up(interface)){

2404

int ret_errno = 0;

2405

int ioctl_errno = 0;

1738

2406

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

1739

2407

ret_errno = errno;

1740

2408

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

1741

2409

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

2410

errno = old_errno;

1742

2411

return ret_errno;

1743

2412

}

1744

2413

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

1745

2414

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

2415

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

2416

if(sd == -1){

1748

2417

ret_errno = errno;

1749

2418

perror_plus("socket");

1750

2419

errno = old_errno;

1756

2425

interface);

1757

2426

}

1758

2427

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

2428

/* Raise privileges */

2429

ret_errno = raise_privileges();

2430

if(ret_errno != 0){

2431

errno = ret_errno;

2432

perror_plus("Failed to raise privileges");

2433

}

2434

2435

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

2436

ioctl_errno = errno;

2437

2438

/* If raise_privileges() succeeded above */

2439

if(ret_errno == 0){

2440

/* Lower privileges */

2441

ret_errno = lower_privileges();

2442

if(ret_errno != 0){

2443

errno = ret_errno;

2444

perror_plus("Failed to lower privileges");

2445

}

2446

}

1767

2447

1768

2448

/* Close the socket */

1769

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

2449

int ret = close(sd);

1770

2450

if(ret == -1){

1771

2451

perror_plus("close");

1772

2452

}

1773

2453

1774

2454

if(ret_setflags == -1){

1775

errno = ret_errno;

2455

errno = ioctl_errno;

1776

2456

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1777

2457

errno = old_errno;

1778

return ret_errno;

2458

return ioctl_errno;

1779

2459

}

1780

2460

} else if(debug){

1781

2461

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

1787

2467

}

1788

2468

1789

2469

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

1790

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

1791

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

1792

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

1793

.interfaces = NULL, .interfaces_size = 0 };

2470

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

2471

#if GNUTLS_VERSION_NUMBER >= 0x030606

2472

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

2473

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

2474

":%PROFILE_ULTRA",

2475

#elif GNUTLS_VERSION_NUMBER < 0x030600

2476

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

2477

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

2478

#else

2479

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

2480

#endif

2481

.current_server = NULL, .interfaces = NULL,

2482

.interfaces_size = 0 };

1794

2483

AvahiSServiceBrowser *sb = NULL;

1795

2484

error_t ret_errno;

1796

2485

int ret;

1799

2488

int exitcode = EXIT_SUCCESS;

1800

2489

char *interfaces_to_take_down = NULL;

1801

2490

size_t interfaces_to_take_down_size = 0;

1802

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

1803

bool tempdir_created = false;

2491

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

2492

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

2493

char *tempdir = NULL;

1804

2494

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1805

2495

const char *seckey = PATHDIR "/" SECKEY;

1806

2496

const char *pubkey = PATHDIR "/" PUBKEY;

2497

#if GNUTLS_VERSION_NUMBER >= 0x030606

2498

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2499

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2500

#endif

2501

const char *dh_params_file = NULL;

1807

2502

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1809

2503

1810

2504

bool gnutls_initialized = false;

1811

2505

bool gpgme_initialized = false;

1857

2551

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

1858

2552

.arg = "FILE",

1859

2553

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

1860

.group = 2 },

2554

.group = 1 },

2555

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

2556

.arg = "FILE",

2557

#if GNUTLS_VERSION_NUMBER >= 0x030606

2558

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

2559

#else

2560

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

2561

#endif

2562

.group = 1 },

2563

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

2564

.arg = "FILE",

2565

#if GNUTLS_VERSION_NUMBER >= 0x030606

2566

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

2567

#else

2568

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

2569

#endif

2570

.group = 1 },

1861

2571

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

1862

2572

.arg = "BITS",

1863

2573

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

1864

2574

" Diffie-Hellman key exchange",

1865

2575

.group = 2 },

2576

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

2577

.arg = "FILE",

2578

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

2579

" for the Diffie-Hellman key exchange",

2580

.group = 2 },

1866

2581

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

1867

2582

.arg = "STRING",

1868

2583

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

1914

2629

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

1915

2630

pubkey = arg;

1916

2631

break;

2632

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

2633

#if GNUTLS_VERSION_NUMBER >= 0x030606

2634

tls_privkey = arg;

2635

#endif

2636

break;

2637

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

2638

#if GNUTLS_VERSION_NUMBER >= 0x030606

2639

tls_pubkey = arg;

2640

#endif

2641

break;

1917

2642

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

1918

2643

errno = 0;

1919

2644

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

1923

2648

}

1924

2649

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

1925

2650

break;

2651

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

2652

dh_params_file = arg;

2653

break;

1926

2654

case 130: /* --priority */

1927

2655

mc.priority = arg;

1928

2656

break;

1951

2679

argp_state_help(state, state->out_stream,

1952

2680

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1953

2681

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2682

__builtin_unreachable();

1954

2683

case -3: /* --usage */

1955

2684

argp_state_help(state, state->out_stream,

1956

2685

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2686

__builtin_unreachable();

1957

2687

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

1958

2688

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

1959

2689

exit(argp_err_exit_status);

1968

2698

.args_doc = "",

1969

2699

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

1970

2700

" passwords from a Mandos server" };

1971

ret = argp_parse(&argp, argc, argv,

1972

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1973

switch(ret){

2701

ret_errno = argp_parse(&argp, argc, argv,

2702

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2703

switch(ret_errno){

1974

2704

case 0:

1975

2705

break;

1976

2706

case ENOMEM:

1977

2707

default:

1978

errno = ret;

2708

errno = ret_errno;

1979

2709

perror_plus("argp_parse");

1980

2710

exitcode = EX_OSERR;

1981

2711

goto end;

1984

2714

goto end;

1985

2715

}

1986

2716

}

1987

2717

1988

2718

{

1989

2719

/* Work around Debian bug #633582:

1990

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

2720

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

1991

2721

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2722

/* Re-raise privileges */

2723

ret = raise_privileges();

2724

if(ret != 0){

2725

errno = ret;

2726

perror_plus("Failed to raise privileges");

2727

} else {

1994

2728

struct stat st;

1995

2729

1996

2730

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

2010

2744

}

2011

2745

}

2012

2746

}

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2747

close(seckey_fd);

2014

2748

}

2015

2749

}

2016

2750

2017

2751

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

2018

2752

int pubkey_fd = open(pubkey, O_RDONLY);

2019

2753

if(pubkey_fd == -1){

2031

2765

}

2032

2766

}

2033

2767

}

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2768

close(pubkey_fd);

2769

}

2770

}

2771

2772

if(dh_params_file != NULL

2773

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

2774

int dhparams_fd = open(dh_params_file, O_RDONLY);

2775

if(dhparams_fd == -1){

2776

perror_plus("open");

2777

} else {

2778

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

2779

if(ret == -1){

2780

perror_plus("fstat");

2781

} else {

2782

if(S_ISREG(st.st_mode)

2783

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

2784

ret = fchown(dhparams_fd, uid, gid);

2785

if(ret == -1){

2786

perror_plus("fchown");

2787

}

2788

}

2789

}

2790

close(dhparams_fd);

2791

}

2792

}

2793

2038

2794

/* Lower privileges */

2039

lower_privileges();

2795

ret = lower_privileges();

2796

if(ret != 0){

2797

errno = ret;

2798

perror_plus("Failed to lower privileges");

2799

}

2040

2800

}

2041

2801

}

2042

2802

2066

2826

goto end;

2067

2827

}

2068

2828

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

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

2072

}

2073

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

2074

interfaces_hooks : "", delay)){

2075

goto end;

2076

}

2829

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

2830

}

2831

run_network_hooks("start", interfaces_hooks != NULL ?

2832

interfaces_hooks : "", delay);

2077

2833

}

2078

2834

2079

2835

if(not debug){

2157

2913

2158

2914

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

2159

2915

if(mc.interfaces == NULL){

2160

struct dirent **direntries;

2916

struct dirent **direntries = NULL;

2161

2917

/* Look for any good interfaces */

2162

2918

ret = scandir(sys_class_net, &direntries, good_interface,

2163

2919

alphasort);

2167

2923

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

2168

2924

direntries[i]->d_name);

2169

2925

if(ret_errno != 0){

2926

errno = ret_errno;

2170

2927

perror_plus("argz_add");

2928

free(direntries[i]);

2171

2929

continue;

2172

2930

}

2173

2931

if(debug){

2174

2932

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

2175

2933

direntries[i]->d_name);

2176

2934

}

2935

free(direntries[i]);

2177

2936

}

2178

2937

free(direntries);

2179

2938

} else {

2180

free(direntries);

2939

if(ret == 0){

2940

free(direntries);

2941

}

2181

2942

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

2182

2943

exitcode = EXIT_FAILURE;

2183

2944

goto end;

2206

2967

break;

2207

2968

}

2208

2969

bool interface_was_up = interface_is_up(interface);

2209

ret = bring_up_interface(interface, delay);

2970

errno = bring_up_interface(interface, delay);

2210

2971

if(not interface_was_up){

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2972

if(errno != 0){

2973

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

2974

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

2214

2975

} else {

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2976

errno = argz_add(&interfaces_to_take_down,

2977

&interfaces_to_take_down_size,

2978

interface);

2979

if(errno != 0){

2980

perror_plus("argz_add");

2981

}

2218

2982

}

2219

2983

}

2220

2984

}

2236

3000

goto end;

2237

3001

}

2238

3002

2239

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

3003

#if GNUTLS_VERSION_NUMBER >= 0x030606

3004

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

3005

#elif GNUTLS_VERSION_NUMBER < 0x030600

3006

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

3007

#else

3008

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

3009

#endif

2240

3010

if(ret == -1){

2241

3011

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

2242

3012

exitcode = EX_UNAVAILABLE;

2249

3019

goto end;

2250

3020

}

2251

3021

2252

if(mkdtemp(tempdir) == NULL){

3022

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

3023

tempdir = mkdtemp(run_tempdir);

3024

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

3025

if(debug){

3026

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

3027

run_tempdir, old_tempdir);

3028

}

3029

tempdir = mkdtemp(old_tempdir);

3030

}

3031

if(tempdir == NULL){

2253

3032

perror_plus("mkdtemp");

2254

3033

goto end;

2255

3034

}

2256

tempdir_created = true;

2257

3035

2258

3036

if(quit_now){

2259

3037

goto end;

2331

3109

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

2332

3110

(int)retry_interval);

2333

3111

}

2334

sleep((int)retry_interval);

3112

sleep((unsigned int)retry_interval);

2335

3113

}

2336

3114

2337

if (not quit_now){

3115

if(not quit_now){

2338

3116

exitcode = EXIT_SUCCESS;

2339

3117

}

2340

3118

2356

3134

2357

3135

/* Allocate a new server */

2358

3136

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2359

&config, NULL, NULL, &ret_errno);

3137

&config, NULL, NULL, &ret);

2360

3138

2361

3139

/* Free the Avahi configuration data */

2362

3140

avahi_server_config_free(&config);

2365

3143

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

2366

3144

if(mc.server == NULL){

2367

3145

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

2368

avahi_strerror(ret_errno));

3146

avahi_strerror(ret));

2369

3147

exitcode = EX_UNAVAILABLE;

2370

3148

goto end;

2371

3149

}

2395

3173

if(debug){

2396

3174

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

2397

3175

}

2398

3176

2399

3177

ret = avahi_loop_with_timeout(simple_poll,

2400

3178

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

2401

3179

if(debug){

2406

3184

end:

2407

3185

2408

3186

if(debug){

2409

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

3187

if(signal_received){

3188

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

3189

argv[0], signal_received,

3190

strsignal(signal_received));

3191

} else {

3192

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

3193

}

2410

3194

}

2411

3195

2412

3196

/* Cleanup things */

2423

3207

2424

3208

if(gnutls_initialized){

2425

3209

gnutls_certificate_free_credentials(mc.cred);

2426

gnutls_global_deinit();

2427

3210

gnutls_dh_params_deinit(mc.dh_params);

2428

3211

}

2429

3212

2437

3220

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

2438

3221

while(mc.current_server != NULL){

2439

3222

server *next = mc.current_server->next;

3223

#ifdef __GNUC__

3224

#pragma GCC diagnostic push

3225

#pragma GCC diagnostic ignored "-Wcast-qual"

3226

#endif

3227

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

3228

#ifdef __GNUC__

3229

#pragma GCC diagnostic pop

3230

#endif

2440

3231

free(mc.current_server);

2441

3232

mc.current_server = next;

2442

3233

}

2443

3234

}

2444

3235

2445

/* Re-raise priviliges */

3236

/* Re-raise privileges */

2446

3237

{

2447

raise_privileges();

2448

2449

/* Run network hooks */

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2452

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

2463

}

2464

}

2465

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

2466

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

2467

" down\n");

2468

}

2469

}

2470

2471

lower_privileges_permanently();

3238

ret = raise_privileges();

3239

if(ret != 0){

3240

errno = ret;

3241

perror_plus("Failed to raise privileges");

3242

} else {

3243

3244

/* Run network hooks */

3245

run_network_hooks("stop", interfaces_hooks != NULL ?

3246

interfaces_hooks : "", delay);

3247

3248

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

3249

{

3250

char *interface = NULL;

3251

while((interface = argz_next(interfaces_to_take_down,

3252

interfaces_to_take_down_size,

3253

interface))){

3254

ret = take_down_interface(interface);

3255

if(ret != 0){

3256

errno = ret;

3257

perror_plus("Failed to take down interface");

3258

}

3259

}

3260

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

3261

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

3262

" down\n");

3263

}

3264

}

3265

}

3266

3267

ret = lower_privileges_permanently();

3268

if(ret != 0){

3269

errno = ret;

3270

perror_plus("Failed to lower privileges permanently");

3271

}

2472

3272

}

2473

3273

2474

3274

free(interfaces_to_take_down);

2475

3275

free(interfaces_hooks);

2476

3276

3277

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

3278

uintmax_t level){

3279

struct dirent **direntries = NULL;

3280

int dret;

3281

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

3282

O_RDONLY

3283

| O_NOFOLLOW

3284

| O_DIRECTORY

3285

| O_PATH));

3286

if(dir_fd == -1){

3287

perror_plus("open");

3288

return;

3289

}

3290

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

3291

notdotentries, alphasort);

3292

if(numentries >= 0){

3293

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

3294

if(debug){

3295

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

3296

dirname, direntries[i]->d_name);

3297

}

3298

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

3299

if(dret == -1){

3300

if(errno == EISDIR){

3301

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

3302

AT_REMOVEDIR);

3303

}

3304

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

3305

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

3306

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

3307

/* Recurse only in this special case */

3308

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

3309

dret = 0;

3310

}

3311

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

3312

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

3313

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

3314

}

3315

}

3316

free(direntries[i]);

3317

}

3318

3319

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

3320

free(direntries);

3321

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3322

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

3323

perror_plus("rmdir");

3324

}

3325

} else {

3326

perror_plus("scandirat");

3327

}

3328

close(dir_fd);

3329

}

3330

2477

3331

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

2478

if(tempdir_created){

2479

struct dirent **direntries = NULL;

2480

struct dirent *direntry = NULL;

2481

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

2482

alphasort);

2483

if (numentries > 0){

2484

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

2485

direntry = direntries[i];

2486

char *fullname = NULL;

2487

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

2488

direntry->d_name);

2489

if(ret < 0){

2490

perror_plus("asprintf");

2491

continue;

2492

}

2493

ret = remove(fullname);

2494

if(ret == -1){

2495

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

2496

strerror(errno));

2497

}

2498

free(fullname);

2499

}

2500

}

2501

2502

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

2503

free(direntries);

2504

if (numentries == -1){

2505

perror_plus("scandir");

2506

}

2507

ret = rmdir(tempdir);

2508

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

2509

perror_plus("rmdir");

2510

}

3332

if(tempdir != NULL){

3333

clean_dir_at(-1, tempdir, 0);

2511

3334

}

2512

3335

2513

3336

if(quit_now){