/mandos/trunk : revision 666

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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 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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*

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

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* along with this program. If not, see

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

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*

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

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*/

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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 /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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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() */

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stdout, ferror(), remove() */

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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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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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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program_invocation_short_name */

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

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#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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unlinkat() */

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

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

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

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

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

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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), nonnull))

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

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

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va_list ap;

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va_start (ap, format);

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* 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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}

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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 };

249

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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 */

275

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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;

279

243

}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return false;

248

}

280

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return true;

281

250

}

282

251

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

286

int old_errno = errno;

287

int ret = 0;

288

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

289

ret = errno;

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}

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errno = old_errno;

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return ret;

293

}

294

295

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

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

298

int old_errno = errno;

299

int ret = raise_privileges();

300

if(ret != 0){

301

errno = old_errno;

302

return ret;

303

}

304

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

310

311

/* 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;

316

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

317

ret = errno;

318

}

319

errno = old_errno;

320

return ret;

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}

322

323

/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

325

int lower_privileges_permanently(void){

326

int old_errno = errno;

327

int ret = 0;

328

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

329

ret = errno;

330

}

331

errno = old_errno;

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return ret;

333

}

334

335

252

/*

336

253

* Initialize GPGME.

337

254

*/

338

__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){

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

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const char *tempdir, mandos_context *mc){

343

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gpgme_error_t rc;

344

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gpgme_engine_info_t engine_info;

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259

346

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/*

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

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*/

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bool import_key(const char * const filename){

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bool import_key(const char *filename){

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int ret;

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int fd;

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gpgme_data_t pgp_data;

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return false;

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}

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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);

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

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struct tm tm;

367

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

368

perror_plus("gmtime_r");

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break;

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}

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

372

break;

373

}

374

if(debug){

375

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

376

}

377

} else {

378

if(debug){

379

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

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

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

400

perror_plus("clock_settime");

401

}

402

ret = lower_privileges();

403

if(ret != 0){

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errno = ret;

405

perror_plus("Failed to lower privileges");

406

}

407

} while(false);

408

409

274

rc = gpgme_data_new_from_fd(&pgp_data, fd);

410

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if(rc != GPG_ERR_NO_ERROR){

411

276

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

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gpgme_strsource(rc), gpgme_strerror(rc));

420

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return false;

421

286

}

422

{

423

gpgme_import_result_t import_result

424

= gpgme_op_import_result(mc->ctx);

425

if((import_result->imported < 1

426

or import_result->not_imported > 0)

427

and import_result->unchanged == 0){

428

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

429

fprintf_plus(stderr,

430

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

431

import_result->considered);

432

fprintf_plus(stderr,

433

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

434

import_result->no_user_id);

435

fprintf_plus(stderr,

436

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

437

import_result->imported);

438

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

439

import_result->imported_rsa);

440

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

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import_result->unchanged);

442

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

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import_result->new_user_ids);

444

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

445

import_result->new_sub_keys);

446

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

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import_result->new_signatures);

448

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

449

import_result->new_revocations);

450

fprintf_plus(stderr,

451

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

452

import_result->secret_read);

453

fprintf_plus(stderr,

454

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

455

import_result->secret_imported);

456

fprintf_plus(stderr,

457

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

458

import_result->secret_unchanged);

459

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

460

import_result->not_imported);

461

for(gpgme_import_status_t import_status

462

= import_result->imports;

463

import_status != NULL;

464

import_status = import_status->next){

465

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

466

import_status->fpr);

467

if(import_status->result != GPG_ERR_NO_ERROR){

468

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

469

gpgme_strsource(import_status->result),

470

gpgme_strerror(import_status->result));

471

}

472

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

473

fprintf_plus(stderr,

474

import_status->status & GPGME_IMPORT_NEW

475

? "The key was new.\n"

476

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

477

fprintf_plus(stderr,

478

import_status->status & GPGME_IMPORT_UID

479

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

480

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

481

fprintf_plus(stderr,

482

import_status->status & GPGME_IMPORT_SIG

483

? "The key contained new signatures.\n"

484

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

485

fprintf_plus(stderr,

486

import_status->status & GPGME_IMPORT_SUBKEY

487

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

488

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

489

fprintf_plus(stderr,

490

import_status->status & GPGME_IMPORT_SECRET

491

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

492

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

493

}

494

return false;

495

}

496

}

497

287

498

ret = close(fd);

288

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

499

289

if(ret == -1){

500

290

perror_plus("close");

501

291

}

540

330

/* Create new GPGME "context" */

541

331

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

542

332

if(rc != GPG_ERR_NO_ERROR){

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

333

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

334

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

335

gpgme_strerror(rc));

545

336

return false;

546

337

}

547

338

556

347

* Decrypt OpenPGP data.

557

348

* Returns -1 on error

558

349

*/

559

__attribute__((nonnull, warn_unused_result))

560

350

static ssize_t pgp_packet_decrypt(const char *cryptotext,

561

351

size_t crypto_size,

562

352

char **plaintext,

583

373

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

584

374

rc = gpgme_data_new(&dh_plain);

585

375

if(rc != GPG_ERR_NO_ERROR){

586

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

376

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

377

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

587

378

gpgme_strsource(rc), gpgme_strerror(rc));

588

379

gpgme_data_release(dh_crypto);

589

380

return -1;

602

393

if(result == NULL){

603

394

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

604

395

} else {

605

if(result->unsupported_algorithm != NULL) {

606

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

607

result->unsupported_algorithm);

608

}

609

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

610

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

396

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

397

result->unsupported_algorithm);

398

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

399

result->wrong_key_usage);

611

400

if(result->file_name != NULL){

612

401

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

613

402

}

614

615

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

616

r = r->next){

403

gpgme_recipient_t recipient;

404

recipient = result->recipients;

405

while(recipient != NULL){

617

406

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

618

gpgme_pubkey_algo_name(r->pubkey_algo));

619

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

407

gpgme_pubkey_algo_name

408

(recipient->pubkey_algo));

409

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

620

410

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

621

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

411

recipient->status == GPG_ERR_NO_SECKEY

412

? "No" : "Yes");

413

recipient = recipient->next;

622

414

}

623

415

}

624

416

}

680

472

return plaintext_length;

681

473

}

682

474

683

__attribute__((warn_unused_result, const))

684

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

685

if(str == NULL)

686

return "(unknown)";

687

return str;

688

}

689

690

__attribute__((warn_unused_result))

691

static const char *safer_gnutls_strerror(int value){

475

static const char * safer_gnutls_strerror(int value){

692

476

const char *ret = gnutls_strerror(value);

693

return safe_string(ret);

477

if(ret == NULL)

478

ret = "(unknown)";

479

return ret;

694

480

}

695

481

696

482

/* GnuTLS log function callback */

697

__attribute__((nonnull))

698

483

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

699

484

const char* string){

700

485

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

701

486

}

702

487

703

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

704

488

static int init_gnutls_global(const char *pubkeyfilename,

705

489

const char *seckeyfilename,

706

const char *dhparamsfilename,

707

490

mandos_context *mc){

708

491

int ret;

709

492

711

494

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

712

495

}

713

496

497

ret = gnutls_global_init();

498

if(ret != GNUTLS_E_SUCCESS){

499

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

500

safer_gnutls_strerror(ret));

501

return -1;

502

}

503

714

504

if(debug){

715

505

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

716

506

* - GnuTLS manual

724

514

if(ret != GNUTLS_E_SUCCESS){

725

515

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

726

516

safer_gnutls_strerror(ret));

517

gnutls_global_deinit();

727

518

return -1;

728

519

}

729

520

730

521

if(debug){

731

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

732

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

522

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

523

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

733

524

pubkeyfilename,

734

525

seckeyfilename);

735

526

}

736

527

737

#if GNUTLS_VERSION_NUMBER >= 0x030606

738

ret = gnutls_certificate_set_rawpk_key_file

739

(mc->cred, pubkeyfilename, seckeyfilename,

740

GNUTLS_X509_FMT_PEM, /* format */

741

NULL, /* pass */

742

/* key_usage */

743

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

744

NULL, /* names */

745

0, /* names_length */

746

/* privkey_flags */

747

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

748

0); /* pkcs11_flags */

749

#elif GNUTLS_VERSION_NUMBER < 0x030600

750

528

ret = gnutls_certificate_set_openpgp_key_file

751

529

(mc->cred, pubkeyfilename, seckeyfilename,

752

530

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

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

755

#endif

756

531

if(ret != GNUTLS_E_SUCCESS){

757

532

fprintf_plus(stderr,

758

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

533

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

759

534

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

760

535

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

761

536

safer_gnutls_strerror(ret));

770

545

safer_gnutls_strerror(ret));

771

546

goto globalfail;

772

547

}

773

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

774

if(dhparamsfilename != NULL){

775

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

776

do {

777

int dhpfile = open(dhparamsfilename, O_RDONLY);

778

if(dhpfile == -1){

779

perror_plus("open");

780

dhparamsfilename = NULL;

781

break;

782

}

783

size_t params_capacity = 0;

784

while(true){

785

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

786

(size_t)params.size,

787

(size_t)params_capacity);

788

if(params_capacity == 0){

789

perror_plus("incbuffer");

790

free(params.data);

791

params.data = NULL;

792

dhparamsfilename = NULL;

793

break;

794

}

795

ssize_t bytes_read = read(dhpfile,

796

params.data + params.size,

797

BUFFER_SIZE);

798

/* EOF */

799

if(bytes_read == 0){

800

break;

801

}

802

/* check bytes_read for failure */

803

if(bytes_read < 0){

804

perror_plus("read");

805

free(params.data);

806

params.data = NULL;

807

dhparamsfilename = NULL;

808

break;

809

}

810

params.size += (unsigned int)bytes_read;

811

}

812

ret = close(dhpfile);

813

if(ret == -1){

814

perror_plus("close");

815

}

816

if(params.data == NULL){

817

dhparamsfilename = NULL;

818

}

819

if(dhparamsfilename == NULL){

820

break;

821

}

822

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

823

GNUTLS_X509_FMT_PEM);

824

if(ret != GNUTLS_E_SUCCESS){

825

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

826

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

827

safer_gnutls_strerror(ret));

828

dhparamsfilename = NULL;

829

}

830

free(params.data);

831

} while(false);

832

}

833

if(dhparamsfilename == NULL){

834

if(mc->dh_bits == 0){

835

#if GNUTLS_VERSION_NUMBER < 0x030600

836

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

837

/* Try to read the private key file */

838

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

839

do {

840

int secfile = open(seckeyfilename, O_RDONLY);

841

if(secfile == -1){

842

perror_plus("open");

843

break;

844

}

845

size_t buffer_capacity = 0;

846

while(true){

847

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

848

(size_t)buffer.size,

849

(size_t)buffer_capacity);

850

if(buffer_capacity == 0){

851

perror_plus("incbuffer");

852

free(buffer.data);

853

buffer.data = NULL;

854

break;

855

}

856

ssize_t bytes_read = read(secfile,

857

buffer.data + buffer.size,

858

BUFFER_SIZE);

859

/* EOF */

860

if(bytes_read == 0){

861

break;

862

}

863

/* check bytes_read for failure */

864

if(bytes_read < 0){

865

perror_plus("read");

866

free(buffer.data);

867

buffer.data = NULL;

868

break;

869

}

870

buffer.size += (unsigned int)bytes_read;

871

}

872

close(secfile);

873

} while(false);

874

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

875

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

876

if(buffer.data != NULL){

877

{

878

gnutls_openpgp_privkey_t privkey = NULL;

879

ret = gnutls_openpgp_privkey_init(&privkey);

880

if(ret != GNUTLS_E_SUCCESS){

881

fprintf_plus(stderr, "Error initializing OpenPGP key"

882

" structure: %s",

883

safer_gnutls_strerror(ret));

884

free(buffer.data);

885

buffer.data = NULL;

886

} else {

887

ret = gnutls_openpgp_privkey_import

888

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

889

if(ret != GNUTLS_E_SUCCESS){

890

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

891

safer_gnutls_strerror(ret));

892

privkey = NULL;

893

}

894

free(buffer.data);

895

buffer.data = NULL;

896

if(privkey != NULL){

897

/* Use private key to suggest an appropriate

898

sec_param */

899

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

900

gnutls_openpgp_privkey_deinit(privkey);

901

if(debug){

902

fprintf_plus(stderr, "This OpenPGP key implies using"

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)));

906

}

907

}

908

}

909

}

910

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

911

/* Err on the side of caution */

912

sec_param = GNUTLS_SEC_PARAM_ULTRA;

913

if(debug){

914

fprintf_plus(stderr, "Falling back to security parameter"

915

" \"%s\"\n",

916

safe_string(gnutls_sec_param_get_name

917

(sec_param)));

918

}

919

}

920

}

921

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

922

if(uret != 0){

923

mc->dh_bits = uret;

924

if(debug){

925

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

926

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

927

safe_string(gnutls_sec_param_get_name

928

(sec_param)),

929

mc->dh_bits);

930

}

931

} else {

932

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

933

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

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)),

936

safer_gnutls_strerror(ret));

937

goto globalfail;

938

}

939

#endif

940

} else { /* dh_bits != 0 */

941

if(debug){

942

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

943

mc->dh_bits);

944

}

945

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

946

if(ret != GNUTLS_E_SUCCESS){

947

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

948

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

949

safer_gnutls_strerror(ret));

950

goto globalfail;

951

}

952

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

953

}

954

}

548

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

549

if(ret != GNUTLS_E_SUCCESS){

550

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

551

safer_gnutls_strerror(ret));

552

goto globalfail;

553

}

554

555

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

955

556

956

557

return 0;

957

558

958

559

globalfail:

959

560

960

561

gnutls_certificate_free_credentials(mc->cred);

562

gnutls_global_deinit();

961

563

gnutls_dh_params_deinit(mc->dh_params);

962

564

return -1;

963

565

}

964

566

965

__attribute__((nonnull, warn_unused_result))

966

567

static int init_gnutls_session(gnutls_session_t *session,

967

568

mandos_context *mc){

968

569

int ret;

969

570

/* GnuTLS session creation */

970

571

do {

971

ret = gnutls_init(session, (GNUTLS_SERVER

972

#if GNUTLS_VERSION_NUMBER >= 0x030506

973

| GNUTLS_NO_TICKETS

974

#endif

975

#if GNUTLS_VERSION_NUMBER >= 0x030606

976

| GNUTLS_ENABLE_RAWPK

977

#endif

978

));

572

ret = gnutls_init(session, GNUTLS_SERVER);

979

573

if(quit_now){

980

574

return -1;

981

575

}

1022

616

/* ignore client certificate if any. */

1023

617

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1024

618

619

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

620

1025

621

return 0;

1026

622

}

1027

623

1029

625

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

1030

626

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

1031

627

1032

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

1033

__attribute__((nonnull, warn_unused_result))

1034

static bool add_delete_local_route(const bool add,

1035

const char *address,

1036

AvahiIfIndex if_index){

1037

int ret;

1038

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

1039

char add_arg[] = "add";

1040

char delete_arg[] = "delete";

1041

char debug_flag[] = "--debug";

1042

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1043

if(pluginhelperdir == NULL){

1044

if(debug){

1045

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1046

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

1047

}

1048

return false;

1049

}

1050

1051

char interface[IF_NAMESIZE];

1052

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

1053

perror_plus("if_indextoname");

1054

return false;

1055

}

1056

1057

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

1058

if(devnull == -1){

1059

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

1060

return false;

1061

}

1062

pid_t pid = fork();

1063

if(pid == 0){

1064

/* Child */

1065

/* Raise privileges */

1066

errno = raise_privileges_permanently();

1067

if(errno != 0){

1068

perror_plus("Failed to raise privileges");

1069

/* _exit(EX_NOPERM); */

1070

} else {

1071

/* Set group */

1072

errno = 0;

1073

ret = setgid(0);

1074

if(ret == -1){

1075

perror_plus("setgid");

1076

close(devnull);

1077

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

close(devnull);

1085

_exit(EX_NOPERM);

1086

}

1087

}

1088

ret = dup2(devnull, STDIN_FILENO);

1089

if(ret == -1){

1090

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

1091

close(devnull);

1092

_exit(EX_OSERR);

1093

}

1094

ret = close(devnull);

1095

if(ret == -1){

1096

perror_plus("close");

1097

}

1098

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1099

if(ret == -1){

1100

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

1101

_exit(EX_OSERR);

1102

}

1103

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

1104

O_RDONLY

1105

| O_DIRECTORY

1106

| O_PATH

1107

| O_CLOEXEC));

1108

if(helperdir_fd == -1){

1109

perror_plus("open");

1110

_exit(EX_UNAVAILABLE);

1111

}

1112

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

1113

helper, O_RDONLY));

1114

if(helper_fd == -1){

1115

perror_plus("openat");

1116

close(helperdir_fd);

1117

_exit(EX_UNAVAILABLE);

1118

}

1119

close(helperdir_fd);

1120

#ifdef __GNUC__

1121

#pragma GCC diagnostic push

1122

#pragma GCC diagnostic ignored "-Wcast-qual"

1123

#endif

1124

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

1125

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

1126

interface, debug ? debug_flag : NULL, NULL },

1127

environ) == -1){

1128

#ifdef __GNUC__

1129

#pragma GCC diagnostic pop

1130

#endif

1131

perror_plus("fexecve");

1132

_exit(EXIT_FAILURE);

1133

}

1134

}

1135

if(pid == -1){

1136

perror_plus("fork");

1137

close(devnull);

1138

return false;

1139

}

1140

ret = close(devnull);

1141

if(ret == -1){

1142

perror_plus("close");

1143

}

1144

int status;

1145

pid_t pret = -1;

1146

errno = 0;

1147

do {

1148

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

1149

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

1150

int errno_raising = 0;

1151

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

1152

errno_raising = errno;

1153

perror_plus("Failed to raise privileges in order to"

1154

" kill helper program");

1155

}

1156

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

1157

perror_plus("kill");

1158

}

1159

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

1160

perror_plus("Failed to lower privileges after killing"

1161

" helper program");

1162

}

1163

return false;

1164

}

1165

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

1166

if(pret == -1){

1167

perror_plus("waitpid");

1168

return false;

1169

}

1170

if(WIFEXITED(status)){

1171

if(WEXITSTATUS(status) != 0){

1172

fprintf_plus(stderr, "Error: iprouteadddel exited"

1173

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

1174

return false;

1175

}

1176

return true;

1177

}

1178

if(WIFSIGNALED(status)){

1179

fprintf_plus(stderr, "Error: iprouteadddel died by"

1180

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

1181

return false;

1182

}

1183

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

1184

return false;

1185

}

1186

1187

__attribute__((nonnull, warn_unused_result))

1188

static bool add_local_route(const char *address,

1189

AvahiIfIndex if_index){

1190

if(debug){

1191

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

1192

}

1193

return add_delete_local_route(true, address, if_index);

1194

}

1195

1196

__attribute__((nonnull, warn_unused_result))

1197

static bool delete_local_route(const char *address,

1198

AvahiIfIndex if_index){

1199

if(debug){

1200

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

1201

}

1202

return add_delete_local_route(false, address, if_index);

1203

}

1204

1205

628

/* Called when a Mandos server is found */

1206

__attribute__((nonnull, warn_unused_result))

1207

629

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

1208

630

AvahiIfIndex if_index,

1209

631

int af, mandos_context *mc){

1210

632

int ret, tcp_sd = -1;

1211

633

ssize_t sret;

1212

struct sockaddr_storage to;

634

union {

635

struct sockaddr_in in;

636

struct sockaddr_in6 in6;

637

} to;

1213

638

char *buffer = NULL;

1214

639

char *decrypted_buffer = NULL;

1215

640

size_t buffer_length = 0;

1218

643

int retval = -1;

1219

644

gnutls_session_t session;

1220

645

int pf; /* Protocol family */

1221

bool route_added = false;

1222

646

1223

647

errno = 0;

1224

648

1246

670

bool match = false;

1247

671

{

1248

672

char *interface = NULL;

1249

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

1250

mc->interfaces_size,

1251

interface))){

673

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

674

interface))){

1252

675

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

1253

676

match = true;

1254

677

break;

1283

706

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

1284

707

}

1285

708

1286

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

709

tcp_sd = socket(pf, SOCK_STREAM, 0);

1287

710

if(tcp_sd < 0){

1288

711

int e = errno;

1289

712

perror_plus("socket");

1296

719

goto mandos_end;

1297

720

}

1298

721

722

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

1299

723

if(af == AF_INET6){

1300

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

1301

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

1302

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

724

to.in6.sin6_family = (sa_family_t)af;

725

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

1303

726

} else { /* IPv4 */

1304

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

1305

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

1306

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

727

to.in.sin_family = (sa_family_t)af;

728

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

1307

729

}

1308

730

if(ret < 0 ){

1309

731

int e = errno;

1318

740

goto mandos_end;

1319

741

}

1320

742

if(af == AF_INET6){

1321

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

1322

if(IN6_IS_ADDR_LINKLOCAL

1323

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

743

to.in6.sin6_port = htons(port);

744

#ifdef __GNUC__

745

#pragma GCC diagnostic push

746

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

747

#endif

748

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

749

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

750

#ifdef __GNUC__

751

#pragma GCC diagnostic pop

752

#endif

1324

753

if(if_index == AVAHI_IF_UNSPEC){

1325

754

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

1326

755

" incomplete without a network interface\n");

1328

757

goto mandos_end;

1329

758

}

1330

759

/* Set the network interface number as scope */

1331

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

760

to.in6.sin6_scope_id = (uint32_t)if_index;

1332

761

}

1333

762

} else {

1334

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

763

to.in.sin_port = htons(port);

1335

764

}

1336

765

1337

766

if(quit_now){

1354

783

}

1355

784

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1356

785

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1357

if(af == AF_INET6){

1358

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

1359

sizeof(struct sockaddr_in6),

1360

addrstr, sizeof(addrstr), NULL, 0,

1361

NI_NUMERICHOST);

1362

} else {

1363

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

1364

sizeof(struct sockaddr_in),

1365

addrstr, sizeof(addrstr), NULL, 0,

1366

NI_NUMERICHOST);

1367

}

1368

if(ret == EAI_SYSTEM){

1369

perror_plus("getnameinfo");

1370

} else if(ret != 0) {

1371

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

1372

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

1373

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

1374

}

1375

}

1376

1377

if(quit_now){

1378

errno = EINTR;

1379

goto mandos_end;

1380

}

1381

1382

while(true){

1383

if(af == AF_INET6){

1384

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

1385

sizeof(struct sockaddr_in6));

1386

} else {

1387

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

1388

sizeof(struct sockaddr_in));

1389

}

1390

if(ret < 0){

1391

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

1392

and if_index != AVAHI_IF_UNSPEC

1393

and connect_to == NULL

1394

and not route_added and

1395

((af == AF_INET6 and not

1396

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1397

&to)->sin6_addr)))

1398

or (af == AF_INET and

1399

/* Not a a IPv4LL address */

1400

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

1401

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

1402

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

1403

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

1404

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

1405

connect to a Mandos server announced by Avahi on a server

1406

host with a global address. Work around this by retrying

1407

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

1408

1409

Avahi bug reference:

1410

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

1411

https://bugs.debian.org/587961

1412

*/

1413

if(debug){

1414

fprintf_plus(stderr, "Mandos server unreachable, trying"

1415

" direct route\n");

1416

}

1417

int e = errno;

1418

route_added = add_local_route(ip, if_index);

1419

if(route_added){

1420

continue;

1421

}

1422

errno = e;

1423

}

1424

if(errno != ECONNREFUSED or debug){

1425

int e = errno;

1426

perror_plus("connect");

1427

errno = e;

1428

}

1429

goto mandos_end;

1430

}

1431

1432

if(quit_now){

1433

errno = EINTR;

1434

goto mandos_end;

1435

}

1436

break;

786

const char *pcret;

787

if(af == AF_INET6){

788

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

789

sizeof(addrstr));

790

} else {

791

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

792

sizeof(addrstr));

793

}

794

if(pcret == NULL){

795

perror_plus("inet_ntop");

796

} else {

797

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

798

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

799

}

800

}

801

}

802

803

if(quit_now){

804

errno = EINTR;

805

goto mandos_end;

806

}

807

808

if(af == AF_INET6){

809

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

810

} else {

811

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

812

}

813

if(ret < 0){

814

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

815

int e = errno;

816

perror_plus("connect");

817

errno = e;

818

}

819

goto mandos_end;

820

}

821

822

if(quit_now){

823

errno = EINTR;

824

goto mandos_end;

1437

825

}

1438

826

1439

827

const char *out = mandos_protocol_version;

1593

981

&decrypted_buffer, mc);

1594

982

if(decrypted_buffer_size >= 0){

1595

983

1596

clearerr(stdout);

1597

984

written = 0;

1598

985

while(written < (size_t) decrypted_buffer_size){

1599

986

if(quit_now){

1615

1002

}

1616

1003

written += (size_t)ret;

1617

1004

}

1618

ret = fflush(stdout);

1619

if(ret != 0){

1620

int e = errno;

1621

if(debug){

1622

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

1623

strerror(errno));

1624

}

1625

errno = e;

1626

goto mandos_end;

1627

}

1628

1005

retval = 0;

1629

1006

}

1630

1007

}

1633

1010

1634

1011

mandos_end:

1635

1012

{

1636

if(route_added){

1637

if(not delete_local_route(ip, if_index)){

1638

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

1639

" interface %d", ip, if_index);

1640

}

1641

}

1642

1013

int e = errno;

1643

1014

free(decrypted_buffer);

1644

1015

free(buffer);

1645

1016

if(tcp_sd >= 0){

1646

ret = close(tcp_sd);

1017

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

1647

1018

}

1648

1019

if(ret == -1){

1649

1020

if(e == 0){

1674

1045

AVAHI_GCC_UNUSED AvahiStringList *txt,

1675

1046

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1676

1047

flags,

1677

void *mc){

1048

void* mc){

1678

1049

if(r == NULL){

1679

1050

return;

1680

1051

}

1683

1054

timed out */

1684

1055

1685

1056

if(quit_now){

1686

avahi_s_service_resolver_free(r);

1687

1057

return;

1688

1058

}

1689

1059

1734

1104

const char *domain,

1735

1105

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1736

1106

flags,

1737

void *mc){

1107

void* mc){

1738

1108

if(b == NULL){

1739

1109

return;

1740

1110

}

1800

1170

errno = old_errno;

1801

1171

}

1802

1172

1803

__attribute__((nonnull, warn_unused_result))

1804

1173

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

1805

1174

int ret;

1806

int old_errno;

1175

error_t ret_errno;

1807

1176

1808

1177

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

1809

1178

if(s < 0){

1810

old_errno = errno;

1179

ret_errno = errno;

1811

1180

perror_plus("socket");

1812

errno = old_errno;

1181

errno = ret_errno;

1813

1182

return false;

1814

1183

}

1815

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

1816

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

1184

strcpy(ifr->ifr_name, ifname);

1817

1185

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1818

1186

if(ret == -1){

1819

1187

if(debug){

1820

old_errno = errno;

1188

ret_errno = errno;

1821

1189

perror_plus("ioctl SIOCGIFFLAGS");

1822

errno = old_errno;

1823

}

1824

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

1825

old_errno = errno;

1826

perror_plus("close");

1827

errno = old_errno;

1190

errno = ret_errno;

1828

1191

}

1829

1192

return false;

1830

1193

}

1831

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

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1836

1194

return true;

1837

1195

}

1838

1196

1839

__attribute__((nonnull, warn_unused_result))

1840

1197

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

1841

1198

1842

1199

/* Reject the loopback device */

1884

1241

* corresponds to an acceptable network device.

1885

1242

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

1886

1243

*/

1887

__attribute__((nonnull, warn_unused_result))

1888

1244

int good_interface(const struct dirent *if_entry){

1889

1245

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

1890

1246

return 0;

1908

1264

/*

1909

1265

* This function determines if a network interface is up.

1910

1266

*/

1911

__attribute__((nonnull, warn_unused_result))

1912

1267

bool interface_is_up(const char *interface){

1913

1268

struct ifreq ifr;

1914

1269

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

1925

1280

/*

1926

1281

* This function determines if a network interface is running

1927

1282

*/

1928

__attribute__((nonnull, warn_unused_result))

1929

1283

bool interface_is_running(const char *interface){

1930

1284

struct ifreq ifr;

1931

1285

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

1939

1293

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

1940

1294

}

1941

1295

1942

__attribute__((nonnull, pure, warn_unused_result))

1943

1296

int notdotentries(const struct dirent *direntry){

1944

1297

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

1945

1298

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

1952

1305

}

1953

1306

1954

1307

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

1955

__attribute__((nonnull, warn_unused_result))

1956

1308

int runnable_hook(const struct dirent *direntry){

1957

1309

int ret;

1958

1310

size_t sret;

1966

1318

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

1967

1319

"abcdefghijklmnopqrstuvwxyz"

1968

1320

"0123456789"

1969

"_.-");

1321

"_-");

1970

1322

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

1971

1323

/* Contains non-allowed characters */

1972

1324

if(debug){

1976

1328

return 0;

1977

1329

}

1978

1330

1979

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

1331

char *fullname = NULL;

1332

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

1333

if(ret < 0){

1334

perror_plus("asprintf");

1335

return 0;

1336

}

1337

1338

ret = stat(fullname, &st);

1980

1339

if(ret == -1){

1981

1340

if(debug){

1982

1341

perror_plus("Could not stat hook");

2006

1365

return 1;

2007

1366

}

2008

1367

2009

__attribute__((nonnull, warn_unused_result))

2010

1368

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2011

1369

mandos_context *mc){

2012

1370

int ret;

2016

1374

2017

1375

while(true){

2018

1376

if(mc->current_server == NULL){

2019

if(debug){

1377

if (debug){

2020

1378

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

2021

1379

" No timeout!\n");

2022

1380

}

2023

1381

ret = avahi_simple_poll_iterate(s, -1);

2024

1382

} else {

2025

if(debug){

1383

if (debug){

2026

1384

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

2027

1385

" it, or wait\n");

2028

1386

}

2045

1403

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

2046

1404

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

2047

1405

2048

if(debug){

1406

if (debug){

2049

1407

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

2050

1408

block_time);

2051

1409

}

2073

1431

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

2074

1432

}

2075

1433

if(ret != 0){

2076

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

1434

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

2077

1435

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

2078

1436

}

2079

1437

}

2080

1438

}

2081

1439

}

2082

1440

2083

__attribute__((nonnull))

2084

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

1441

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

1442

error_t raise_privileges(void){

1443

error_t old_errno = errno;

1444

error_t ret_errno = 0;

1445

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

1446

ret_errno = errno;

1447

perror_plus("seteuid");

1448

}

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

1453

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

1454

error_t raise_privileges_permanently(void){

1455

error_t old_errno = errno;

1456

error_t ret_errno = raise_privileges();

1457

if(ret_errno != 0){

1458

errno = old_errno;

1459

return ret_errno;

1460

}

1461

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

1462

ret_errno = errno;

1463

perror_plus("seteuid");

1464

}

1465

errno = old_errno;

1466

return ret_errno;

1467

}

1468

1469

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

1470

error_t lower_privileges(void){

1471

error_t old_errno = errno;

1472

error_t ret_errno = 0;

1473

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

1474

ret_errno = errno;

1475

perror_plus("seteuid");

1476

}

1477

errno = old_errno;

1478

return ret_errno;

1479

}

1480

1481

/* Lower privileges permanently */

1482

error_t lower_privileges_permanently(void){

1483

error_t old_errno = errno;

1484

error_t ret_errno = 0;

1485

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

1486

ret_errno = errno;

1487

perror_plus("setuid");

1488

}

1489

errno = old_errno;

1490

return ret_errno;

1491

}

1492

1493

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

2085

1494

const float delay){

2086

struct dirent **direntries = NULL;

2087

if(hookdir_fd == -1){

2088

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2089

| O_CLOEXEC);

2090

if(hookdir_fd == -1){

2091

if(errno == ENOENT){

2092

if(debug){

2093

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

2094

" found\n", hookdir);

2095

}

2096

} else {

2097

perror_plus("open");

2098

}

2099

return;

2100

}

2101

}

2102

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

2103

if(devnull == -1){

2104

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

2105

return;

2106

}

2107

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

2108

runnable_hook, alphasort);

1495

struct dirent **direntries;

1496

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

1497

alphasort);

2109

1498

if(numhooks == -1){

2110

perror_plus("scandir");

2111

close(devnull);

2112

return;

2113

}

2114

struct dirent *direntry;

2115

int ret;

2116

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

2117

direntry = direntries[i];

2118

if(debug){

2119

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

2120

direntry->d_name);

1499

if(errno == ENOENT){

1500

if(debug){

1501

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

1502

" found\n", hookdir);

1503

}

1504

} else {

1505

perror_plus("scandir");

2121

1506

}

2122

pid_t hook_pid = fork();

2123

if(hook_pid == 0){

2124

/* Child */

2125

/* Raise privileges */

2126

errno = raise_privileges_permanently();

2127

if(errno != 0){

2128

perror_plus("Failed to raise privileges");

2129

_exit(EX_NOPERM);

2130

}

2131

/* Set group */

2132

errno = 0;

2133

ret = setgid(0);

2134

if(ret == -1){

2135

perror_plus("setgid");

2136

_exit(EX_NOPERM);

2137

}

2138

/* Reset supplementary groups */

2139

errno = 0;

2140

ret = setgroups(0, NULL);

2141

if(ret == -1){

2142

perror_plus("setgroups");

2143

_exit(EX_NOPERM);

2144

}

2145

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

2146

if(ret == -1){

2147

perror_plus("setenv");

2148

_exit(EX_OSERR);

2149

}

2150

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

2151

if(ret == -1){

2152

perror_plus("setenv");

2153

_exit(EX_OSERR);

2154

}

2155

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

2156

if(ret == -1){

2157

perror_plus("setenv");

2158

_exit(EX_OSERR);

2159

}

2160

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

2161

if(ret == -1){

2162

perror_plus("setenv");

2163

_exit(EX_OSERR);

2164

}

2165

char *delaystring;

2166

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

2167

if(ret == -1){

1507

} else {

1508

struct dirent *direntry;

1509

int ret;

1510

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

1511

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

1512

direntry = direntries[i];

1513

char *fullname = NULL;

1514

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

1515

if(ret < 0){

2168

1516

perror_plus("asprintf");

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

if(ret == -1){

1517

continue;

1518

}

1519

if(debug){

1520

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

1521

direntry->d_name);

1522

}

1523

pid_t hook_pid = fork();

1524

if(hook_pid == 0){

1525

/* Child */

1526

/* Raise privileges */

1527

raise_privileges_permanently();

1528

/* Set group */

1529

errno = 0;

1530

ret = setgid(0);

1531

if(ret == -1){

1532

perror_plus("setgid");

1533

}

1534

/* Reset supplementary groups */

1535

errno = 0;

1536

ret = setgroups(0, NULL);

1537

if(ret == -1){

1538

perror_plus("setgroups");

1539

}

1540

dup2(devnull, STDIN_FILENO);

1541

close(devnull);

1542

dup2(STDERR_FILENO, STDOUT_FILENO);

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

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

1559

if(ret == -1){

1560

perror_plus("setenv");

1561

_exit(EX_OSERR);

1562

}

1563

char *delaystring;

1564

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

1565

if(ret == -1){

1566

perror_plus("asprintf");

1567

_exit(EX_OSERR);

1568

}

1569

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

1570

if(ret == -1){

1571

free(delaystring);

1572

perror_plus("setenv");

1573

_exit(EX_OSERR);

1574

}

2173

1575

free(delaystring);

2174

perror_plus("setenv");

2175

_exit(EX_OSERR);

2176

}

2177

free(delaystring);

2178

if(connect_to != NULL){

2179

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

2180

if(ret == -1){

2181

perror_plus("setenv");

2182

_exit(EX_OSERR);

2183

}

2184

}

2185

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

2186

direntry->d_name,

2187

O_RDONLY));

2188

if(hook_fd == -1){

2189

perror_plus("openat");

2190

_exit(EXIT_FAILURE);

2191

}

2192

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

2193

perror_plus("close");

2194

_exit(EXIT_FAILURE);

2195

}

2196

ret = dup2(devnull, STDIN_FILENO);

2197

if(ret == -1){

2198

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

2199

_exit(EX_OSERR);

2200

}

2201

ret = close(devnull);

2202

if(ret == -1){

2203

perror_plus("close");

2204

_exit(EX_OSERR);

2205

}

2206

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2207

if(ret == -1){

2208

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

2209

_exit(EX_OSERR);

2210

}

2211

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

2212

environ) == -1){

2213

perror_plus("fexecve");

2214

_exit(EXIT_FAILURE);

2215

}

2216

} else {

2217

if(hook_pid == -1){

2218

perror_plus("fork");

2219

free(direntry);

2220

continue;

2221

}

2222

int status;

2223

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

2224

perror_plus("waitpid");

2225

free(direntry);

2226

continue;

2227

}

2228

if(WIFEXITED(status)){

2229

if(WEXITSTATUS(status) != 0){

2230

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

2231

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

2232

WEXITSTATUS(status));

2233

free(direntry);

2234

continue;

2235

}

2236

} else if(WIFSIGNALED(status)){

2237

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

2238

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

2239

WTERMSIG(status));

2240

free(direntry);

2241

continue;

1576

if(connect_to != NULL){

1577

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

1578

if(ret == -1){

1579

perror_plus("setenv");

1580

_exit(EX_OSERR);

1581

}

1582

}

1583

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

1584

perror_plus("execl");

1585

_exit(EXIT_FAILURE);

1586

}

2242

1587

} else {

2243

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

2244

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

2245

free(direntry);

2246

continue;

2247

}

2248

}

2249

if(debug){

2250

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

2251

direntry->d_name);

2252

}

2253

free(direntry);

2254

}

2255

free(direntries);

2256

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

2257

perror_plus("close");

2258

} else {

2259

hookdir_fd = -1;

2260

}

2261

close(devnull);

1588

int status;

1589

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

1590

perror_plus("waitpid");

1591

free(fullname);

1592

continue;

1593

}

1594

if(WIFEXITED(status)){

1595

if(WEXITSTATUS(status) != 0){

1596

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

1597

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

1598

WEXITSTATUS(status));

1599

free(fullname);

1600

continue;

1601

}

1602

} else if(WIFSIGNALED(status)){

1603

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

1604

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

1605

WTERMSIG(status));

1606

free(fullname);

1607

continue;

1608

} else {

1609

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

1610

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

1611

free(fullname);

1612

continue;

1613

}

1614

}

1615

free(fullname);

1616

if(debug){

1617

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

1618

direntry->d_name);

1619

}

1620

}

1621

close(devnull);

1622

}

1623

return true;

2262

1624

}

2263

1625

2264

__attribute__((nonnull, warn_unused_result))

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

2268

int ret;

1626

error_t bring_up_interface(const char *const interface,

1627

const float delay){

1628

int sd = -1;

1629

error_t old_errno = errno;

1630

error_t ret_errno = 0;

1631

int ret, ret_setflags;

2269

1632

struct ifreq network;

2270

1633

unsigned int if_index = if_nametoindex(interface);

2271

1634

if(if_index == 0){

2280

1643

}

2281

1644

2282

1645

if(not interface_is_up(interface)){

2283

int ret_errno = 0;

2284

int ioctl_errno = 0;

2285

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

1646

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

2286

1647

ret_errno = errno;

2287

1648

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

2288

1649

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

2289

errno = old_errno;

2290

1650

return ret_errno;

2291

1651

}

2292

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

1652

network.ifr_flags |= IFF_UP;

2293

1653

2294

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

2295

if(sd == -1){

1654

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1655

if(sd < 0){

2296

1656

ret_errno = errno;

2297

1657

perror_plus("socket");

2298

1658

errno = old_errno;

2299

1659

return ret_errno;

2300

1660

}

2301

1661

2302

1662

if(quit_now){

2303

ret = close(sd);

2304

if(ret == -1){

2305

perror_plus("close");

2306

}

1663

close(sd);

2307

1664

errno = old_errno;

2308

1665

return EINTR;

2309

1666

}

2313

1670

interface);

2314

1671

}

2315

1672

2316

/* Raise privileges */

2317

ret_errno = raise_privileges();

2318

if(ret_errno != 0){

2319

errno = ret_errno;

2320

perror_plus("Failed to raise privileges");

2321

}

1673

/* Raise priviliges */

1674

raise_privileges();

2322

1675

2323

1676

#ifdef __linux__

2324

int ret_linux;

2325

bool restore_loglevel = false;

2326

if(ret_errno == 0){

2327

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2328

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

2329

ret_linux = klogctl(8, NULL, 5);

2330

if(ret_linux == -1){

2331

perror_plus("klogctl");

2332

} else {

2333

restore_loglevel = true;

2334

}

1677

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1678

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

1679

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

1680

bool restore_loglevel = true;

1681

if(ret_linux == -1){

1682

restore_loglevel = false;

1683

perror_plus("klogctl");

2335

1684

}

2336

1685

#endif /* __linux__ */

2337

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

2338

ioctl_errno = errno;

1686

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

1687

ret_errno = errno;

2339

1688

#ifdef __linux__

2340

1689

if(restore_loglevel){

2341

1690

ret_linux = klogctl(7, NULL, 0);

2345

1694

}

2346

1695

#endif /* __linux__ */

2347

1696

2348

/* If raise_privileges() succeeded above */

2349

if(ret_errno == 0){

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

1697

/* Lower privileges */

1698

lower_privileges();

2357

1699

2358

1700

/* Close the socket */

2359

ret = close(sd);

1701

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

2360

1702

if(ret == -1){

2361

1703

perror_plus("close");

2362

1704

}

2363

1705

2364

1706

if(ret_setflags == -1){

2365

errno = ioctl_errno;

1707

errno = ret_errno;

2366

1708

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2367

1709

errno = old_errno;

2368

return ioctl_errno;

1710

return ret_errno;

2369

1711

}

2370

1712

} else if(debug){

2371

1713

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

2374

1716

2375

1717

/* Sleep checking until interface is running.

2376

1718

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

2377

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

1719

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

2378

1720

if(interface_is_running(interface)){

2379

1721

break;

2380

1722

}

2389

1731

return 0;

2390

1732

}

2391

1733

2392

__attribute__((nonnull, warn_unused_result))

2393

int take_down_interface(const char *const interface){

2394

int old_errno = errno;

1734

error_t take_down_interface(const char *const interface){

1735

error_t old_errno = errno;

2395

1736

struct ifreq network;

2396

1737

unsigned int if_index = if_nametoindex(interface);

2397

1738

if(if_index == 0){

2400

1741

return ENXIO;

2401

1742

}

2402

1743

if(interface_is_up(interface)){

2403

int ret_errno = 0;

2404

int ioctl_errno = 0;

1744

error_t ret_errno = 0;

2405

1745

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

2406

1746

ret_errno = errno;

2407

1747

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

2408

1748

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

2409

errno = old_errno;

2410

1749

return ret_errno;

2411

1750

}

2412

1751

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

2413

1752

2414

1753

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

2415

if(sd == -1){

1754

if(sd < 0){

2416

1755

ret_errno = errno;

2417

1756

perror_plus("socket");

2418

1757

errno = old_errno;

2424

1763

interface);

2425

1764

}

2426

1765

2427

/* Raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

}

1766

/* Raise priviliges */

1767

raise_privileges();

2433

1768

2434

1769

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

2435

ioctl_errno = errno;

1770

ret_errno = errno;

2436

1771

2437

/* If raise_privileges() succeeded above */

2438

if(ret_errno == 0){

2439

/* Lower privileges */

2440

ret_errno = lower_privileges();

2441

if(ret_errno != 0){

2442

errno = ret_errno;

2443

perror_plus("Failed to lower privileges");

2444

}

2445

}

1772

/* Lower privileges */

1773

lower_privileges();

2446

1774

2447

1775

/* Close the socket */

2448

int ret = close(sd);

1776

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

2449

1777

if(ret == -1){

2450

1778

perror_plus("close");

2451

1779

}

2452

1780

2453

1781

if(ret_setflags == -1){

2454

errno = ioctl_errno;

1782

errno = ret_errno;

2455

1783

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2456

1784

errno = old_errno;

2457

return ioctl_errno;

1785

return ret_errno;

2458

1786

}

2459

1787

} else if(debug){

2460

1788

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

2466

1794

}

2467

1795

2468

1796

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

2469

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

2470

#if GNUTLS_VERSION_NUMBER >= 0x030606

2471

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

2472

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

2473

":%PROFILE_ULTRA",

2474

#elif GNUTLS_VERSION_NUMBER < 0x030600

2475

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

2476

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

2477

#else

2478

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

2479

#endif

2480

.current_server = NULL, .interfaces = NULL,

2481

.interfaces_size = 0 };

1797

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

1798

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

1799

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

1800

.interfaces = NULL, .interfaces_size = 0 };

2482

1801

AvahiSServiceBrowser *sb = NULL;

2483

1802

error_t ret_errno;

2484

1803

int ret;

2487

1806

int exitcode = EXIT_SUCCESS;

2488

1807

char *interfaces_to_take_down = NULL;

2489

1808

size_t interfaces_to_take_down_size = 0;

2490

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

2491

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

2492

char *tempdir = NULL;

1809

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

1810

bool tempdir_created = false;

2493

1811

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2494

1812

const char *seckey = PATHDIR "/" SECKEY;

2495

1813

const char *pubkey = PATHDIR "/" PUBKEY;

2496

#if GNUTLS_VERSION_NUMBER >= 0x030606

2497

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2498

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2499

#endif

2500

const char *dh_params_file = NULL;

2501

1814

char *interfaces_hooks = NULL;

2502

1815

2503

1816

bool gnutls_initialized = false;

2550

1863

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

2551

1864

.arg = "FILE",

2552

1865

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

2553

.group = 1 },

2554

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

2555

.arg = "FILE",

2556

#if GNUTLS_VERSION_NUMBER >= 0x030606

2557

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

2558

#else

2559

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

2560

#endif

2561

.group = 1 },

2562

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

2563

.arg = "FILE",

2564

#if GNUTLS_VERSION_NUMBER >= 0x030606

2565

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

2566

#else

2567

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

2568

#endif

2569

.group = 1 },

1866

.group = 2 },

2570

1867

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

2571

1868

.arg = "BITS",

2572

1869

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

2573

1870

" Diffie-Hellman key exchange",

2574

1871

.group = 2 },

2575

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

2576

.arg = "FILE",

2577

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

2578

" for the Diffie-Hellman key exchange",

2579

.group = 2 },

2580

1872

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

2581

1873

.arg = "STRING",

2582

1874

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

2628

1920

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

2629

1921

pubkey = arg;

2630

1922

break;

2631

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

2632

#if GNUTLS_VERSION_NUMBER >= 0x030606

2633

tls_privkey = arg;

2634

#endif

2635

break;

2636

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

2637

#if GNUTLS_VERSION_NUMBER >= 0x030606

2638

tls_pubkey = arg;

2639

#endif

2640

break;

2641

1923

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

2642

1924

errno = 0;

2643

1925

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

2647

1929

}

2648

1930

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

2649

1931

break;

2650

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

2651

dh_params_file = arg;

2652

break;

2653

1932

case 130: /* --priority */

2654

1933

mc.priority = arg;

2655

1934

break;

2678

1957

argp_state_help(state, state->out_stream,

2679

1958

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2680

1959

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

2682

1960

case -3: /* --usage */

2683

1961

argp_state_help(state, state->out_stream,

2684

1962

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

2686

1963

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

2687

1964

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

2688

1965

exit(argp_err_exit_status);

2697

1974

.args_doc = "",

2698

1975

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

2699

1976

" passwords from a Mandos server" };

2700

ret_errno = argp_parse(&argp, argc, argv,

2701

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2702

switch(ret_errno){

1977

ret = argp_parse(&argp, argc, argv,

1978

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1979

switch(ret){

2703

1980

case 0:

2704

1981

break;

2705

1982

case ENOMEM:

2706

1983

default:

2707

errno = ret_errno;

1984

errno = ret;

2708

1985

perror_plus("argp_parse");

2709

1986

exitcode = EX_OSERR;

2710

1987

goto end;

2713

1990

goto end;

2714

1991

}

2715

1992

}

2716

1993

2717

1994

{

2718

1995

/* Work around Debian bug #633582:

2719

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

1996

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

2720

1997

2721

/* Re-raise privileges */

2722

ret = raise_privileges();

2723

if(ret != 0){

2724

errno = ret;

2725

perror_plus("Failed to raise privileges");

2726

} else {

1998

/* Re-raise priviliges */

1999

if(raise_privileges() == 0){

2727

2000

struct stat st;

2728

2001

2729

2002

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

2743

2016

}

2744

2017

}

2745

2018

}

2746

close(seckey_fd);

2019

TEMP_FAILURE_RETRY(close(seckey_fd));

2747

2020

}

2748

2021

}

2749

2022

2750

2023

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

2751

2024

int pubkey_fd = open(pubkey, O_RDONLY);

2752

2025

if(pubkey_fd == -1){

2764

2037

}

2765

2038

}

2766

2039

}

2767

close(pubkey_fd);

2768

}

2769

}

2770

2771

if(dh_params_file != NULL

2772

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

2773

int dhparams_fd = open(dh_params_file, O_RDONLY);

2774

if(dhparams_fd == -1){

2775

perror_plus("open");

2776

} else {

2777

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

2778

if(ret == -1){

2779

perror_plus("fstat");

2780

} else {

2781

if(S_ISREG(st.st_mode)

2782

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

2783

ret = fchown(dhparams_fd, uid, gid);

2784

if(ret == -1){

2785

perror_plus("fchown");

2786

}

2787

}

2788

}

2789

close(dhparams_fd);

2790

}

2791

}

2792

2040

TEMP_FAILURE_RETRY(close(pubkey_fd));

2041

}

2042

}

2043

2793

2044

/* Lower privileges */

2794

ret = lower_privileges();

2795

if(ret != 0){

2796

errno = ret;

2797

perror_plus("Failed to lower privileges");

2798

}

2045

lower_privileges();

2799

2046

}

2800

2047

}

2801

2048

2827

2074

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

2828

2075

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

2829

2076

}

2830

run_network_hooks("start", interfaces_hooks != NULL ?

2831

interfaces_hooks : "", delay);

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2832

2081

}

2833

2082

2834

2083

if(not debug){

2912

2161

2913

2162

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

2914

2163

if(mc.interfaces == NULL){

2915

struct dirent **direntries = NULL;

2164

struct dirent **direntries;

2916

2165

/* Look for any good interfaces */

2917

2166

ret = scandir(sys_class_net, &direntries, good_interface,

2918

2167

alphasort);

2924

2173

if(ret_errno != 0){

2925

2174

errno = ret_errno;

2926

2175

perror_plus("argz_add");

2927

free(direntries[i]);

2928

2176

continue;

2929

2177

}

2930

2178

if(debug){

2931

2179

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

2932

2180

direntries[i]->d_name);

2933

2181

}

2934

free(direntries[i]);

2935

2182

}

2936

2183

free(direntries);

2937

2184

} else {

2938

if(ret == 0){

2939

free(direntries);

2940

}

2185

free(direntries);

2941

2186

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

2942

2187

exitcode = EXIT_FAILURE;

2943

2188

goto end;

2966

2211

break;

2967

2212

}

2968

2213

bool interface_was_up = interface_is_up(interface);

2969

errno = bring_up_interface(interface, delay);

2214

ret = bring_up_interface(interface, delay);

2970

2215

if(not interface_was_up){

2971

if(errno != 0){

2972

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

2973

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

2216

if(ret != 0){

2217

errno = ret;

2218

perror_plus("Failed to bring up interface");

2974

2219

} else {

2975

errno = argz_add(&interfaces_to_take_down,

2976

&interfaces_to_take_down_size,

2977

interface);

2978

if(errno != 0){

2220

ret_errno = argz_add(&interfaces_to_take_down,

2221

&interfaces_to_take_down_size,

2222

interface);

2223

if(ret_errno != 0){

2224

errno = ret_errno;

2979

2225

perror_plus("argz_add");

2980

2226

}

2981

2227

}

2999

2245

goto end;

3000

2246

}

3001

2247

3002

#if GNUTLS_VERSION_NUMBER >= 0x030606

3003

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

3004

#elif GNUTLS_VERSION_NUMBER < 0x030600

3005

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

3006

#else

3007

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

3008

#endif

2248

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

3009

2249

if(ret == -1){

3010

2250

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

3011

2251

exitcode = EX_UNAVAILABLE;

3018

2258

goto end;

3019

2259

}

3020

2260

3021

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

3022

tempdir = mkdtemp(run_tempdir);

3023

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

3024

if(debug){

3025

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

3026

run_tempdir, old_tempdir);

3027

}

3028

tempdir = mkdtemp(old_tempdir);

3029

}

3030

if(tempdir == NULL){

2261

if(mkdtemp(tempdir) == NULL){

3031

2262

perror_plus("mkdtemp");

3032

2263

goto end;

3033

2264

}

2265

tempdir_created = true;

3034

2266

3035

2267

if(quit_now){

3036

2268

goto end;

3111

2343

sleep((unsigned int)retry_interval);

3112

2344

}

3113

2345

3114

if(not quit_now){

2346

if (not quit_now){

3115

2347

exitcode = EXIT_SUCCESS;

3116

2348

}

3117

2349

3133

2365

3134

2366

/* Allocate a new server */

3135

2367

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3136

&config, NULL, NULL, &ret);

2368

&config, NULL, NULL, &ret_errno);

3137

2369

3138

2370

/* Free the Avahi configuration data */

3139

2371

avahi_server_config_free(&config);

3142

2374

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

3143

2375

if(mc.server == NULL){

3144

2376

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

3145

avahi_strerror(ret));

2377

avahi_strerror(ret_errno));

3146

2378

exitcode = EX_UNAVAILABLE;

3147

2379

goto end;

3148

2380

}

3172

2404

if(debug){

3173

2405

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

3174

2406

}

3175

2407

3176

2408

ret = avahi_loop_with_timeout(simple_poll,

3177

2409

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

3178

2410

if(debug){

3183

2415

end:

3184

2416

3185

2417

if(debug){

3186

if(signal_received){

3187

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

3188

argv[0], signal_received,

3189

strsignal(signal_received));

3190

} else {

3191

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

3192

}

2418

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

3193

2419

}

3194

2420

3195

2421

/* Cleanup things */

3206

2432

3207

2433

if(gnutls_initialized){

3208

2434

gnutls_certificate_free_credentials(mc.cred);

2435

gnutls_global_deinit();

3209

2436

gnutls_dh_params_deinit(mc.dh_params);

3210

2437

}

3211

2438

3219

2446

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

3220

2447

while(mc.current_server != NULL){

3221

2448

server *next = mc.current_server->next;

3222

#ifdef __GNUC__

3223

#pragma GCC diagnostic push

3224

#pragma GCC diagnostic ignored "-Wcast-qual"

3225

#endif

3226

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

3227

#ifdef __GNUC__

3228

#pragma GCC diagnostic pop

3229

#endif

3230

2449

free(mc.current_server);

3231

2450

mc.current_server = next;

3232

2451

}

3233

2452

}

3234

2453

3235

/* Re-raise privileges */

2454

/* Re-raise priviliges */

3236

2455

{

3237

ret = raise_privileges();

3238

if(ret != 0){

3239

errno = ret;

3240

perror_plus("Failed to raise privileges");

3241

} else {

3242

3243

/* Run network hooks */

3244

run_network_hooks("stop", interfaces_hooks != NULL ?

3245

interfaces_hooks : "", delay);

3246

3247

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

3248

{

3249

char *interface = NULL;

3250

while((interface = argz_next(interfaces_to_take_down,

3251

interfaces_to_take_down_size,

3252

interface))){

3253

ret = take_down_interface(interface);

3254

if(ret != 0){

3255

errno = ret;

3256

perror_plus("Failed to take down interface");

3257

}

3258

}

3259

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

3260

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

3261

" down\n");

3262

}

3263

}

3264

}

3265

3266

ret = lower_privileges_permanently();

3267

if(ret != 0){

3268

errno = ret;

3269

perror_plus("Failed to lower privileges permanently");

3270

}

2456

raise_privileges();

2457

2458

/* Run network hooks */

2459

run_network_hooks("stop", interfaces_hooks != NULL ?

2460

interfaces_hooks : "", delay);

2461

2462

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

2463

{

2464

char *interface = NULL;

2465

while((interface=argz_next(interfaces_to_take_down,

2466

interfaces_to_take_down_size,

2467

interface))){

2468

ret_errno = take_down_interface(interface);

2469

if(ret_errno != 0){

2470

errno = ret_errno;

2471

perror_plus("Failed to take down interface");

2472

}

2473

}

2474

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

2475

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

2476

" down\n");

2477

}

2478

}

2479

2480

lower_privileges_permanently();

3271

2481

}

3272

2482

3273

2483

free(interfaces_to_take_down);

3274

2484

free(interfaces_hooks);

3275

2485

3276

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

3277

uintmax_t level){

2486

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

2487

if(tempdir_created){

3278

2488

struct dirent **direntries = NULL;

3279

int dret;

3280

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

3281

O_RDONLY

3282

| O_NOFOLLOW

3283

| O_DIRECTORY

3284

| O_PATH));

3285

if(dir_fd == -1){

3286

perror_plus("open");

3287

return;

3288

}

3289

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

3290

notdotentries, alphasort);

3291

if(numentries >= 0){

2489

struct dirent *direntry = NULL;

2490

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

2491

alphasort);

2492

if (numentries > 0){

3292

2493

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

3293

if(debug){

3294

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

3295

dirname, direntries[i]->d_name);

3296

}

3297

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

3298

if(dret == -1){

3299

if(errno == EISDIR){

3300

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

3301

AT_REMOVEDIR);

3302

}

3303

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

3304

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

3305

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

3306

/* Recurse only in this special case */

3307

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

3308

dret = 0;

3309

}

3310

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

3311

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

3312

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

3313

}

3314

}

3315

free(direntries[i]);

3316

}

3317

3318

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

3319

free(direntries);

3320

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3321

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

3322

perror_plus("rmdir");

3323

}

3324

} else {

3325

perror_plus("scandirat");

3326

}

3327

close(dir_fd);

3328

}

3329

3330

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

3331

if(tempdir != NULL){

3332

clean_dir_at(-1, tempdir, 0);

2494

direntry = direntries[i];

2495

char *fullname = NULL;

2496

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

2497

direntry->d_name);

2498

if(ret < 0){

2499

perror_plus("asprintf");

2500

continue;

2501

}

2502

ret = remove(fullname);

2503

if(ret == -1){

2504

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

2505

strerror(errno));

2506

}

2507

free(fullname);

2508

}

2509

}

2510

2511

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

2512

free(direntries);

2513

if (numentries == -1){

2514

perror_plus("scandir");

2515

}

2516

ret = rmdir(tempdir);

2517

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

2518

perror_plus("rmdir");

2519

}

3333

2520

}

3334

2521

3335

2522

if(quit_now){