/mandos/release : revision 237.7.672

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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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#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() */

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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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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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123

gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

126

#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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145

#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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162

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perror(print_text);

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}

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

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

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

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va_list ap;

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va_start (ap, format);

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* bytes. "buffer_capacity" is how much is currently allocated,

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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}

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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__

263

#pragma GCC diagnostic pop

264

#endif

265

free(new_server);

238

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return false;

239

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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;

248

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

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new_server->prev->next = new_server;

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return true;

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}

254

282

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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;

290

}

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errno = old_errno;

292

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){

305

ret = errno;

306

}

307

errno = old_errno;

308

return ret;

309

}

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;

315

int ret = 0;

316

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

317

ret = errno;

318

}

319

errno = old_errno;

320

return ret;

321

}

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;

332

return ret;

333

}

334

255

335

/*

256

336

* Initialize GPGME.

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337

*/

258

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

259

const char *tempdir, mandos_context *mc){

338

__attribute__((nonnull, warn_unused_result))

339

static bool init_gpgme(const char * const seckey,

340

const char * const pubkey,

341

const char * const tempdir,

342

mandos_context *mc){

260

343

gpgme_error_t rc;

261

344

gpgme_engine_info_t engine_info;

262

345

263

346

/*

264

347

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

265

348

*/

266

bool import_key(const char *filename){

349

bool import_key(const char * const filename){

267

350

int ret;

268

351

int fd;

269

352

gpgme_data_t pgp_data;

274

357

return false;

275

358

}

276

359

360

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

361

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

362

do {

363

{

364

time_t currtime = time(NULL);

365

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

366

struct tm tm;

367

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

368

perror_plus("gmtime_r");

369

break;

370

}

371

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

372

break;

373

}

374

if(debug){

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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

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){

405

errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

277

410

rc = gpgme_data_new_from_fd(&pgp_data, fd);

278

411

if(rc != GPG_ERR_NO_ERROR){

279

412

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

287

420

gpgme_strsource(rc), gpgme_strerror(rc));

288

421

return false;

289

422

}

423

{

424

gpgme_import_result_t import_result

425

= 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,

434

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

435

import_result->no_user_id);

436

fprintf_plus(stderr,

437

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

438

import_result->imported);

439

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

440

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

}

290

498

291

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

499

ret = close(fd);

292

500

if(ret == -1){

293

501

perror_plus("close");

294

502

}

333

541

/* Create new GPGME "context" */

334

542

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

335

543

if(rc != GPG_ERR_NO_ERROR){

336

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

337

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

338

gpgme_strerror(rc));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

339

546

return false;

340

547

}

341

548

350

557

* Decrypt OpenPGP data.

351

558

* Returns -1 on error

352

559

*/

560

__attribute__((nonnull, warn_unused_result))

353

561

static ssize_t pgp_packet_decrypt(const char *cryptotext,

354

562

size_t crypto_size,

355

563

char **plaintext,

376

584

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

377

585

rc = gpgme_data_new(&dh_plain);

378

586

if(rc != GPG_ERR_NO_ERROR){

379

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

380

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

587

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

381

588

gpgme_strsource(rc), gpgme_strerror(rc));

382

589

gpgme_data_release(dh_crypto);

383

590

return -1;

396

603

if(result == NULL){

397

604

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

398

605

} else {

399

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

400

result->unsupported_algorithm);

401

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

402

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");

403

612

if(result->file_name != NULL){

404

613

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

405

614

}

406

gpgme_recipient_t recipient;

407

recipient = result->recipients;

408

while(recipient != NULL){

615

616

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

617

r = r->next){

409

618

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

410

gpgme_pubkey_algo_name

411

(recipient->pubkey_algo));

412

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);

413

621

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

414

recipient->status == GPG_ERR_NO_SECKEY

415

? "No" : "Yes");

416

recipient = recipient->next;

622

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

417

623

}

418

624

}

419

625

}

475

681

return plaintext_length;

476

682

}

477

683

478

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){

479

693

const char *ret = gnutls_strerror(value);

480

if(ret == NULL)

481

ret = "(unknown)";

482

return ret;

694

return safe_string(ret);

483

695

}

484

696

485

697

/* GnuTLS log function callback */

698

__attribute__((nonnull))

486

699

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

487

700

const char* string){

488

701

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

489

702

}

490

703

704

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

491

705

static int init_gnutls_global(const char *pubkeyfilename,

492

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

493

708

mandos_context *mc){

494

709

int ret;

495

710

497

712

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

498

713

}

499

714

500

ret = gnutls_global_init();

501

if(ret != GNUTLS_E_SUCCESS){

502

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

503

safer_gnutls_strerror(ret));

504

return -1;

505

}

506

507

715

if(debug){

508

716

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

509

717

* - GnuTLS manual

517

725

if(ret != GNUTLS_E_SUCCESS){

518

726

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

519

727

safer_gnutls_strerror(ret));

520

gnutls_global_deinit();

521

728

return -1;

522

729

}

523

730

524

731

if(debug){

525

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

526

" 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",

527

734

pubkeyfilename,

528

735

seckeyfilename);

529

736

}

530

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

531

751

ret = gnutls_certificate_set_openpgp_key_file

532

752

(mc->cred, pubkeyfilename, seckeyfilename,

533

753

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

534

757

if(ret != GNUTLS_E_SUCCESS){

535

758

fprintf_plus(stderr,

536

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

759

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

537

760

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

538

761

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

539

762

safer_gnutls_strerror(ret));

548

771

safer_gnutls_strerror(ret));

549

772

goto globalfail;

550

773

}

551

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

552

if(ret != GNUTLS_E_SUCCESS){

553

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

554

safer_gnutls_strerror(ret));

555

goto globalfail;

556

}

557

558

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

}

559

956

560

957

return 0;

561

958

562

959

globalfail:

563

960

564

961

gnutls_certificate_free_credentials(mc->cred);

565

gnutls_global_deinit();

566

962

gnutls_dh_params_deinit(mc->dh_params);

567

963

return -1;

568

964

}

569

965

966

__attribute__((nonnull, warn_unused_result))

570

967

static int init_gnutls_session(gnutls_session_t *session,

571

968

mandos_context *mc){

572

969

int ret;

573

970

/* GnuTLS session creation */

574

971

do {

575

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

));

576

980

if(quit_now){

577

981

return -1;

578

982

}

619

1023

/* ignore client certificate if any. */

620

1024

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

621

1025

622

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

623

624

1026

return 0;

625

1027

}

626

1028

628

1030

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

629

1031

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

630

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

_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

_exit(EX_NOPERM);

1085

}

1086

}

1087

ret = dup2(devnull, STDIN_FILENO);

1088

if(ret == -1){

1089

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

1090

_exit(EX_OSERR);

1091

}

1092

ret = close(devnull);

1093

if(ret == -1){

1094

perror_plus("close");

1095

_exit(EX_OSERR);

1096

}

1097

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1098

if(ret == -1){

1099

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

1100

_exit(EX_OSERR);

1101

}

1102

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

1103

O_RDONLY

1104

| O_DIRECTORY

1105

| O_PATH

1106

| O_CLOEXEC));

1107

if(helperdir_fd == -1){

1108

perror_plus("open");

1109

_exit(EX_UNAVAILABLE);

1110

}

1111

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

1112

helper, O_RDONLY));

1113

if(helper_fd == -1){

1114

perror_plus("openat");

1115

close(helperdir_fd);

1116

_exit(EX_UNAVAILABLE);

1117

}

1118

close(helperdir_fd);

1119

#ifdef __GNUC__

1120

#pragma GCC diagnostic push

1121

#pragma GCC diagnostic ignored "-Wcast-qual"

1122

#endif

1123

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

1124

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

1125

interface, debug ? debug_flag : NULL, NULL },

1126

environ) == -1){

1127

#ifdef __GNUC__

1128

#pragma GCC diagnostic pop

1129

#endif

1130

perror_plus("fexecve");

1131

_exit(EXIT_FAILURE);

1132

}

1133

}

1134

if(pid == -1){

1135

perror_plus("fork");

1136

return false;

1137

}

1138

int status;

1139

pid_t pret = -1;

1140

errno = 0;

1141

do {

1142

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

1143

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

1144

int errno_raising = 0;

1145

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

1146

errno_raising = errno;

1147

perror_plus("Failed to raise privileges in order to"

1148

" kill helper program");

1149

}

1150

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

1151

perror_plus("kill");

1152

}

1153

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

1154

perror_plus("Failed to lower privileges after killing"

1155

" helper program");

1156

}

1157

return false;

1158

}

1159

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

1160

if(pret == -1){

1161

perror_plus("waitpid");

1162

return false;

1163

}

1164

if(WIFEXITED(status)){

1165

if(WEXITSTATUS(status) != 0){

1166

fprintf_plus(stderr, "Error: iprouteadddel exited"

1167

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

1168

return false;

1169

}

1170

return true;

1171

}

1172

if(WIFSIGNALED(status)){

1173

fprintf_plus(stderr, "Error: iprouteadddel died by"

1174

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

1175

return false;

1176

}

1177

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

1178

return false;

1179

}

1180

1181

__attribute__((nonnull, warn_unused_result))

1182

static bool add_local_route(const char *address,

1183

AvahiIfIndex if_index){

1184

if(debug){

1185

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

1186

}

1187

return add_delete_local_route(true, address, if_index);

1188

}

1189

1190

__attribute__((nonnull, warn_unused_result))

1191

static bool delete_local_route(const char *address,

1192

AvahiIfIndex if_index){

1193

if(debug){

1194

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

1195

}

1196

return add_delete_local_route(false, address, if_index);

1197

}

1198

631

1199

/* Called when a Mandos server is found */

1200

__attribute__((nonnull, warn_unused_result))

632

1201

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

633

1202

AvahiIfIndex if_index,

634

1203

int af, mandos_context *mc){

635

1204

int ret, tcp_sd = -1;

636

1205

ssize_t sret;

637

union {

638

struct sockaddr_in in;

639

struct sockaddr_in6 in6;

640

} to;

1206

struct sockaddr_storage to;

641

1207

char *buffer = NULL;

642

1208

char *decrypted_buffer = NULL;

643

1209

size_t buffer_length = 0;

646

1212

int retval = -1;

647

1213

gnutls_session_t session;

648

1214

int pf; /* Protocol family */

1215

bool route_added = false;

649

1216

650

1217

errno = 0;

651

1218

673

1240

bool match = false;

674

1241

{

675

1242

char *interface = NULL;

676

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

677

interface))){

1243

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

1244

mc->interfaces_size,

1245

interface))){

678

1246

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

679

1247

match = true;

680

1248

break;

709

1277

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

710

1278

}

711

1279

712

tcp_sd = socket(pf, SOCK_STREAM, 0);

1280

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

713

1281

if(tcp_sd < 0){

714

1282

int e = errno;

715

1283

perror_plus("socket");

722

1290

goto mandos_end;

723

1291

}

724

1292

725

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

726

1293

if(af == AF_INET6){

727

to.in6.sin6_family = (sa_family_t)af;

728

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

1294

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

1295

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

1296

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

729

1297

} else { /* IPv4 */

730

to.in.sin_family = (sa_family_t)af;

731

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

1298

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

1299

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

1300

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

732

1301

}

733

1302

if(ret < 0 ){

734

1303

int e = errno;

743

1312

goto mandos_end;

744

1313

}

745

1314

if(af == AF_INET6){

746

to.in6.sin6_port = htons(port);

747

#ifdef __GNUC__

748

#pragma GCC diagnostic push

749

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

750

#endif

751

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

752

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

753

#ifdef __GNUC__

754

#pragma GCC diagnostic pop

755

#endif

1315

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

1316

if(IN6_IS_ADDR_LINKLOCAL

1317

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

756

1318

if(if_index == AVAHI_IF_UNSPEC){

757

1319

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

758

1320

" incomplete without a network interface\n");

760

1322

goto mandos_end;

761

1323

}

762

1324

/* Set the network interface number as scope */

763

to.in6.sin6_scope_id = (uint32_t)if_index;

1325

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

764

1326

}

765

1327

} else {

766

to.in.sin_port = htons(port);

1328

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

767

1329

}

768

1330

769

1331

if(quit_now){

787

1349

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

788

1350

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

789

1351

if(af == AF_INET6){

790

ret = getnameinfo((struct sockaddr *)&(to.in6), sizeof(to.in6),

1352

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

1353

sizeof(struct sockaddr_in6),

791

1354

addrstr, sizeof(addrstr), NULL, 0,

792

1355

NI_NUMERICHOST);

793

1356

} else {

794

ret = getnameinfo((struct sockaddr *)&(to.in), sizeof(to.in),

1357

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

1358

sizeof(struct sockaddr_in),

795

1359

addrstr, sizeof(addrstr), NULL, 0,

796

1360

NI_NUMERICHOST);

797

1361

}

809

1373

goto mandos_end;

810

1374

}

811

1375

812

if(af == AF_INET6){

813

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

814

} else {

815

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

816

}

817

if(ret < 0){

818

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

819

int e = errno;

820

perror_plus("connect");

821

errno = e;

822

}

823

goto mandos_end;

824

}

825

826

if(quit_now){

827

errno = EINTR;

828

goto mandos_end;

1376

while(true){

1377

if(af == AF_INET6){

1378

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

1379

sizeof(struct sockaddr_in6));

1380

} else {

1381

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

1382

sizeof(struct sockaddr_in));

1383

}

1384

if(ret < 0){

1385

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

1386

and if_index != AVAHI_IF_UNSPEC

1387

and connect_to == NULL

1388

and not route_added and

1389

((af == AF_INET6 and not

1390

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1391

&to)->sin6_addr)))

1392

or (af == AF_INET and

1393

/* Not a a IPv4LL address */

1394

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

1395

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

1396

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

1397

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

1398

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

1399

connect to a Mandos server announced by Avahi on a server

1400

host with a global address. Work around this by retrying

1401

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

1402

1403

Avahi bug reference:

1404

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

1405

https://bugs.debian.org/587961

1406

*/

1407

if(debug){

1408

fprintf_plus(stderr, "Mandos server unreachable, trying"

1409

" direct route\n");

1410

}

1411

int e = errno;

1412

route_added = add_local_route(ip, if_index);

1413

if(route_added){

1414

continue;

1415

}

1416

errno = e;

1417

}

1418

if(errno != ECONNREFUSED or debug){

1419

int e = errno;

1420

perror_plus("connect");

1421

errno = e;

1422

}

1423

goto mandos_end;

1424

}

1425

1426

if(quit_now){

1427

errno = EINTR;

1428

goto mandos_end;

1429

}

1430

break;

829

1431

}

830

1432

831

1433

const char *out = mandos_protocol_version;

985

1587

&decrypted_buffer, mc);

986

1588

if(decrypted_buffer_size >= 0){

987

1589

1590

clearerr(stdout);

988

1591

written = 0;

989

1592

while(written < (size_t) decrypted_buffer_size){

990

1593

if(quit_now){

1006

1609

}

1007

1610

written += (size_t)ret;

1008

1611

}

1612

ret = fflush(stdout);

1613

if(ret != 0){

1614

int e = errno;

1615

if(debug){

1616

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

1617

strerror(errno));

1618

}

1619

errno = e;

1620

goto mandos_end;

1621

}

1009

1622

retval = 0;

1010

1623

}

1011

1624

}

1014

1627

1015

1628

mandos_end:

1016

1629

{

1630

if(route_added){

1631

if(not delete_local_route(ip, if_index)){

1632

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

1633

" interface %d", ip, if_index);

1634

}

1635

}

1017

1636

int e = errno;

1018

1637

free(decrypted_buffer);

1019

1638

free(buffer);

1020

1639

if(tcp_sd >= 0){

1021

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

1640

ret = close(tcp_sd);

1022

1641

}

1023

1642

if(ret == -1){

1024

1643

if(e == 0){

1049

1668

AVAHI_GCC_UNUSED AvahiStringList *txt,

1050

1669

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1051

1670

flags,

1052

void* mc){

1671

void *mc){

1053

1672

if(r == NULL){

1054

1673

return;

1055

1674

}

1058

1677

timed out */

1059

1678

1060

1679

if(quit_now){

1680

avahi_s_service_resolver_free(r);

1061

1681

return;

1062

1682

}

1063

1683

1108

1728

const char *domain,

1109

1729

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1110

1730

flags,

1111

void* mc){

1731

void *mc){

1112

1732

if(b == NULL){

1113

1733

return;

1114

1734

}

1174

1794

errno = old_errno;

1175

1795

}

1176

1796

1797

__attribute__((nonnull, warn_unused_result))

1177

1798

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

1178

1799

int ret;

1179

error_t ret_errno;

1800

int old_errno;

1180

1801

1181

1802

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

1182

1803

if(s < 0){

1183

ret_errno = errno;

1804

old_errno = errno;

1184

1805

perror_plus("socket");

1185

errno = ret_errno;

1806

errno = old_errno;

1186

1807

return false;

1187

1808

}

1188

strcpy(ifr->ifr_name, ifname);

1809

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

1810

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

1189

1811

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1190

1812

if(ret == -1){

1191

1813

if(debug){

1192

ret_errno = errno;

1814

old_errno = errno;

1193

1815

perror_plus("ioctl SIOCGIFFLAGS");

1194

errno = ret_errno;

1816

errno = old_errno;

1817

}

1818

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

1819

old_errno = errno;

1820

perror_plus("close");

1821

errno = old_errno;

1195

1822

}

1196

1823

return false;

1197

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1829

}

1198

1830

return true;

1199

1831

}

1200

1832

1833

__attribute__((nonnull, warn_unused_result))

1201

1834

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

1202

1835

1203

1836

/* Reject the loopback device */

1245

1878

* corresponds to an acceptable network device.

1246

1879

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

1247

1880

*/

1881

__attribute__((nonnull, warn_unused_result))

1248

1882

int good_interface(const struct dirent *if_entry){

1249

1883

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

1250

1884

return 0;

1268

1902

/*

1269

1903

* This function determines if a network interface is up.

1270

1904

*/

1905

__attribute__((nonnull, warn_unused_result))

1271

1906

bool interface_is_up(const char *interface){

1272

1907

struct ifreq ifr;

1273

1908

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

1284

1919

/*

1285

1920

* This function determines if a network interface is running

1286

1921

*/

1922

__attribute__((nonnull, warn_unused_result))

1287

1923

bool interface_is_running(const char *interface){

1288

1924

struct ifreq ifr;

1289

1925

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

1297

1933

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

1298

1934

}

1299

1935

1936

__attribute__((nonnull, pure, warn_unused_result))

1300

1937

int notdotentries(const struct dirent *direntry){

1301

1938

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

1302

1939

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

1309

1946

}

1310

1947

1311

1948

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

1949

__attribute__((nonnull, warn_unused_result))

1312

1950

int runnable_hook(const struct dirent *direntry){

1313

1951

int ret;

1314

1952

size_t sret;

1322

1960

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

1323

1961

"abcdefghijklmnopqrstuvwxyz"

1324

1962

"0123456789"

1325

"_-");

1963

"_.-");

1326

1964

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

1327

1965

/* Contains non-allowed characters */

1328

1966

if(debug){

1332

1970

return 0;

1333

1971

}

1334

1972

1335

char *fullname = NULL;

1336

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

1337

if(ret < 0){

1338

perror_plus("asprintf");

1339

return 0;

1340

}

1341

1342

ret = stat(fullname, &st);

1973

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

1343

1974

if(ret == -1){

1344

1975

if(debug){

1345

1976

perror_plus("Could not stat hook");

1369

2000

return 1;

1370

2001

}

1371

2002

2003

__attribute__((nonnull, warn_unused_result))

1372

2004

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1373

2005

mandos_context *mc){

1374

2006

int ret;

1378

2010

1379

2011

while(true){

1380

2012

if(mc->current_server == NULL){

1381

if (debug){

2013

if(debug){

1382

2014

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

1383

2015

" No timeout!\n");

1384

2016

}

1385

2017

ret = avahi_simple_poll_iterate(s, -1);

1386

2018

} else {

1387

if (debug){

2019

if(debug){

1388

2020

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

1389

2021

" it, or wait\n");

1390

2022

}

1407

2039

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

1408

2040

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

1409

2041

1410

if (debug){

2042

if(debug){

1411

2043

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

1412

2044

block_time);

1413

2045

}

1435

2067

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

1436

2068

}

1437

2069

if(ret != 0){

1438

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

2070

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

1439

2071

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

1440

2072

}

1441

2073

}

1442

2074

}

1443

2075

}

1444

2076

1445

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

1446

error_t raise_privileges(void){

1447

error_t old_errno = errno;

1448

error_t ret_errno = 0;

1449

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

1450

ret_errno = errno;

1451

perror_plus("seteuid");

1452

}

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

1457

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

1458

error_t raise_privileges_permanently(void){

1459

error_t old_errno = errno;

1460

error_t ret_errno = raise_privileges();

1461

if(ret_errno != 0){

1462

errno = old_errno;

1463

return ret_errno;

1464

}

1465

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

1466

ret_errno = errno;

1467

perror_plus("seteuid");

1468

}

1469

errno = old_errno;

1470

return ret_errno;

1471

}

1472

1473

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

1474

error_t lower_privileges(void){

1475

error_t old_errno = errno;

1476

error_t ret_errno = 0;

1477

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

1478

ret_errno = errno;

1479

perror_plus("seteuid");

1480

}

1481

errno = old_errno;

1482

return ret_errno;

1483

}

1484

1485

/* Lower privileges permanently */

1486

error_t lower_privileges_permanently(void){

1487

error_t old_errno = errno;

1488

error_t ret_errno = 0;

1489

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

1490

ret_errno = errno;

1491

perror_plus("setuid");

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

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

2077

__attribute__((nonnull))

2078

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

1498

2079

const float delay){

1499

struct dirent **direntries;

1500

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

1501

alphasort);

2080

struct dirent **direntries = NULL;

2081

if(hookdir_fd == -1){

2082

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2083

| O_CLOEXEC);

2084

if(hookdir_fd == -1){

2085

if(errno == ENOENT){

2086

if(debug){

2087

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

2088

" found\n", hookdir);

2089

}

2090

} else {

2091

perror_plus("open");

2092

}

2093

return;

2094

}

2095

}

2096

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

2097

if(devnull == -1){

2098

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

2099

return;

2100

}

2101

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

2102

runnable_hook, alphasort);

1502

2103

if(numhooks == -1){

1503

if(errno == ENOENT){

1504

if(debug){

1505

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

1506

" found\n", hookdir);

1507

}

1508

} else {

1509

perror_plus("scandir");

2104

perror_plus("scandir");

2105

close(devnull);

2106

return;

2107

}

2108

struct dirent *direntry;

2109

int ret;

2110

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

2111

direntry = direntries[i];

2112

if(debug){

2113

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

2114

direntry->d_name);

1510

2115

}

1511

} else {

1512

struct dirent *direntry;

1513

int ret;

1514

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

1515

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

1516

direntry = direntries[i];

1517

char *fullname = NULL;

1518

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

1519

if(ret < 0){

2116

pid_t hook_pid = fork();

2117

if(hook_pid == 0){

2118

/* Child */

2119

/* Raise privileges */

2120

errno = raise_privileges_permanently();

2121

if(errno != 0){

2122

perror_plus("Failed to raise privileges");

2123

_exit(EX_NOPERM);

2124

}

2125

/* Set group */

2126

errno = 0;

2127

ret = setgid(0);

2128

if(ret == -1){

2129

perror_plus("setgid");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Reset supplementary groups */

2133

errno = 0;

2134

ret = setgroups(0, NULL);

2135

if(ret == -1){

2136

perror_plus("setgroups");

2137

_exit(EX_NOPERM);

2138

}

2139

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

2140

if(ret == -1){

2141

perror_plus("setenv");

2142

_exit(EX_OSERR);

2143

}

2144

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

2145

if(ret == -1){

2146

perror_plus("setenv");

2147

_exit(EX_OSERR);

2148

}

2149

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

2150

if(ret == -1){

2151

perror_plus("setenv");

2152

_exit(EX_OSERR);

2153

}

2154

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

2155

if(ret == -1){

2156

perror_plus("setenv");

2157

_exit(EX_OSERR);

2158

}

2159

char *delaystring;

2160

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

2161

if(ret == -1){

1520

2162

perror_plus("asprintf");

1521

continue;

1522

}

1523

if(debug){

1524

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

1525

direntry->d_name);

1526

}

1527

pid_t hook_pid = fork();

1528

if(hook_pid == 0){

1529

/* Child */

1530

/* Raise privileges */

1531

raise_privileges_permanently();

1532

/* Set group */

1533

errno = 0;

1534

ret = setgid(0);

1535

if(ret == -1){

1536

perror_plus("setgid");

1537

}

1538

/* Reset supplementary groups */

1539

errno = 0;

1540

ret = setgroups(0, NULL);

1541

if(ret == -1){

1542

perror_plus("setgroups");

1543

}

1544

dup2(devnull, STDIN_FILENO);

1545

close(devnull);

1546

dup2(STDERR_FILENO, STDOUT_FILENO);

1547

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

1548

if(ret == -1){

1549

perror_plus("setenv");

1550

_exit(EX_OSERR);

1551

}

1552

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

1553

if(ret == -1){

1554

perror_plus("setenv");

1555

_exit(EX_OSERR);

1556

}

1557

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

1558

if(ret == -1){

1559

perror_plus("setenv");

1560

_exit(EX_OSERR);

1561

}

1562

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

1563

if(ret == -1){

1564

perror_plus("setenv");

1565

_exit(EX_OSERR);

1566

}

1567

char *delaystring;

1568

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

1569

if(ret == -1){

1570

perror_plus("asprintf");

1571

_exit(EX_OSERR);

1572

}

1573

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

1574

if(ret == -1){

1575

free(delaystring);

1576

perror_plus("setenv");

1577

_exit(EX_OSERR);

1578

}

2163

_exit(EX_OSERR);

2164

}

2165

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

2166

if(ret == -1){

1579

2167

free(delaystring);

1580

if(connect_to != NULL){

1581

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

1582

if(ret == -1){

1583

perror_plus("setenv");

1584

_exit(EX_OSERR);

1585

}

1586

}

1587

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

1588

perror_plus("execl");

1589

_exit(EXIT_FAILURE);

1590

}

2168

perror_plus("setenv");

2169

_exit(EX_OSERR);

2170

}

2171

free(delaystring);

2172

if(connect_to != NULL){

2173

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

2174

if(ret == -1){

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

}

2179

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

2180

direntry->d_name,

2181

O_RDONLY));

2182

if(hook_fd == -1){

2183

perror_plus("openat");

2184

_exit(EXIT_FAILURE);

2185

}

2186

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

2187

perror_plus("close");

2188

_exit(EXIT_FAILURE);

2189

}

2190

ret = dup2(devnull, STDIN_FILENO);

2191

if(ret == -1){

2192

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

2193

_exit(EX_OSERR);

2194

}

2195

ret = close(devnull);

2196

if(ret == -1){

2197

perror_plus("close");

2198

_exit(EX_OSERR);

2199

}

2200

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2201

if(ret == -1){

2202

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

2203

_exit(EX_OSERR);

2204

}

2205

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

2206

environ) == -1){

2207

perror_plus("fexecve");

2208

_exit(EXIT_FAILURE);

2209

}

2210

} else {

2211

if(hook_pid == -1){

2212

perror_plus("fork");

2213

free(direntry);

2214

continue;

2215

}

2216

int status;

2217

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

2218

perror_plus("waitpid");

2219

free(direntry);

2220

continue;

2221

}

2222

if(WIFEXITED(status)){

2223

if(WEXITSTATUS(status) != 0){

2224

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

2225

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

2226

WEXITSTATUS(status));

2227

free(direntry);

2228

continue;

2229

}

2230

} else if(WIFSIGNALED(status)){

2231

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

2232

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

2233

WTERMSIG(status));

2234

free(direntry);

2235

continue;

1591

2236

} else {

1592

int status;

1593

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

1594

perror_plus("waitpid");

1595

free(fullname);

1596

continue;

1597

}

1598

if(WIFEXITED(status)){

1599

if(WEXITSTATUS(status) != 0){

1600

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

1601

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

1602

WEXITSTATUS(status));

1603

free(fullname);

1604

continue;

1605

}

1606

} else if(WIFSIGNALED(status)){

1607

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

1608

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

1609

WTERMSIG(status));

1610

free(fullname);

1611

continue;

1612

} else {

1613

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

1614

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

1615

free(fullname);

1616

continue;

1617

}

1618

}

1619

free(fullname);

1620

if(debug){

1621

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

1622

direntry->d_name);

1623

}

1624

}

1625

close(devnull);

1626

}

1627

return true;

2237

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

2238

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

2239

free(direntry);

2240

continue;

2241

}

2242

}

2243

if(debug){

2244

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

2245

direntry->d_name);

2246

}

2247

free(direntry);

2248

}

2249

free(direntries);

2250

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

2251

perror_plus("close");

2252

} else {

2253

hookdir_fd = -1;

2254

}

2255

close(devnull);

1628

2256

}

1629

2257

1630

error_t bring_up_interface(const char *const interface,

1631

const float delay){

1632

int sd = -1;

1633

error_t old_errno = errno;

1634

error_t ret_errno = 0;

1635

int ret, ret_setflags;

2258

__attribute__((nonnull, warn_unused_result))

2259

int bring_up_interface(const char *const interface,

2260

const float delay){

2261

int old_errno = errno;

2262

int ret;

1636

2263

struct ifreq network;

1637

2264

unsigned int if_index = if_nametoindex(interface);

1638

2265

if(if_index == 0){

1647

2274

}

1648

2275

1649

2276

if(not interface_is_up(interface)){

1650

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

2277

int ret_errno = 0;

2278

int ioctl_errno = 0;

2279

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

1651

2280

ret_errno = errno;

1652

2281

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

1653

2282

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

2283

errno = old_errno;

1654

2284

return ret_errno;

1655

2285

}

1656

network.ifr_flags |= IFF_UP;

2286

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

1657

2287

1658

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1659

if(sd < 0){

2288

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

2289

if(sd == -1){

1660

2290

ret_errno = errno;

1661

2291

perror_plus("socket");

1662

2292

errno = old_errno;

1663

2293

return ret_errno;

1664

2294

}

1665

2295

1666

2296

if(quit_now){

1667

close(sd);

2297

ret = close(sd);

2298

if(ret == -1){

2299

perror_plus("close");

2300

}

1668

2301

errno = old_errno;

1669

2302

return EINTR;

1670

2303

}

1674

2307

interface);

1675

2308

}

1676

2309

1677

/* Raise priviliges */

1678

raise_privileges();

2310

/* Raise privileges */

2311

ret_errno = raise_privileges();

2312

if(ret_errno != 0){

2313

errno = ret_errno;

2314

perror_plus("Failed to raise privileges");

2315

}

1679

2316

1680

2317

#ifdef __linux__

1681

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1682

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

1683

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

1684

bool restore_loglevel = true;

1685

if(ret_linux == -1){

1686

restore_loglevel = false;

1687

perror_plus("klogctl");

2318

int ret_linux;

2319

bool restore_loglevel = false;

2320

if(ret_errno == 0){

2321

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2322

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

2323

ret_linux = klogctl(8, NULL, 5);

2324

if(ret_linux == -1){

2325

perror_plus("klogctl");

2326

} else {

2327

restore_loglevel = true;

2328

}

1688

2329

}

1689

2330

#endif /* __linux__ */

1690

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

1691

ret_errno = errno;

2331

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

2332

ioctl_errno = errno;

1692

2333

#ifdef __linux__

1693

2334

if(restore_loglevel){

1694

2335

ret_linux = klogctl(7, NULL, 0);

1698

2339

}

1699

2340

#endif /* __linux__ */

1700

2341

1701

/* Lower privileges */

1702

lower_privileges();

2342

/* If raise_privileges() succeeded above */

2343

if(ret_errno == 0){

2344

/* Lower privileges */

2345

ret_errno = lower_privileges();

2346

if(ret_errno != 0){

2347

errno = ret_errno;

2348

perror_plus("Failed to lower privileges");

2349

}

2350

}

1703

2351

1704

2352

/* Close the socket */

1705

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

2353

ret = close(sd);

1706

2354

if(ret == -1){

1707

2355

perror_plus("close");

1708

2356

}

1709

2357

1710

2358

if(ret_setflags == -1){

1711

errno = ret_errno;

2359

errno = ioctl_errno;

1712

2360

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1713

2361

errno = old_errno;

1714

return ret_errno;

2362

return ioctl_errno;

1715

2363

}

1716

2364

} else if(debug){

1717

2365

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

1720

2368

1721

2369

/* Sleep checking until interface is running.

1722

2370

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

1723

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

2371

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

1724

2372

if(interface_is_running(interface)){

1725

2373

break;

1726

2374

}

1735

2383

return 0;

1736

2384

}

1737

2385

1738

error_t take_down_interface(const char *const interface){

1739

error_t old_errno = errno;

2386

__attribute__((nonnull, warn_unused_result))

2387

int take_down_interface(const char *const interface){

2388

int old_errno = errno;

1740

2389

struct ifreq network;

1741

2390

unsigned int if_index = if_nametoindex(interface);

1742

2391

if(if_index == 0){

1745

2394

return ENXIO;

1746

2395

}

1747

2396

if(interface_is_up(interface)){

1748

error_t ret_errno = 0;

2397

int ret_errno = 0;

2398

int ioctl_errno = 0;

1749

2399

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

1750

2400

ret_errno = errno;

1751

2401

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

1752

2402

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

2403

errno = old_errno;

1753

2404

return ret_errno;

1754

2405

}

1755

2406

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

1756

2407

1757

2408

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

1758

if(sd < 0){

2409

if(sd == -1){

1759

2410

ret_errno = errno;

1760

2411

perror_plus("socket");

1761

2412

errno = old_errno;

1767

2418

interface);

1768

2419

}

1769

2420

1770

/* Raise priviliges */

1771

raise_privileges();

2421

/* Raise privileges */

2422

ret_errno = raise_privileges();

2423

if(ret_errno != 0){

2424

errno = ret_errno;

2425

perror_plus("Failed to raise privileges");

2426

}

1772

2427

1773

2428

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

1774

ret_errno = errno;

2429

ioctl_errno = errno;

1775

2430

1776

/* Lower privileges */

1777

lower_privileges();

2431

/* If raise_privileges() succeeded above */

2432

if(ret_errno == 0){

2433

/* Lower privileges */

2434

ret_errno = lower_privileges();

2435

if(ret_errno != 0){

2436

errno = ret_errno;

2437

perror_plus("Failed to lower privileges");

2438

}

2439

}

1778

2440

1779

2441

/* Close the socket */

1780

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

2442

int ret = close(sd);

1781

2443

if(ret == -1){

1782

2444

perror_plus("close");

1783

2445

}

1784

2446

1785

2447

if(ret_setflags == -1){

1786

errno = ret_errno;

2448

errno = ioctl_errno;

1787

2449

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1788

2450

errno = old_errno;

1789

return ret_errno;

2451

return ioctl_errno;

1790

2452

}

1791

2453

} else if(debug){

1792

2454

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

1798

2460

}

1799

2461

1800

2462

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

1801

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

1802

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

1803

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

1804

.interfaces = NULL, .interfaces_size = 0 };

2463

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

2464

#if GNUTLS_VERSION_NUMBER >= 0x030606

2465

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

2466

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

2467

":%PROFILE_ULTRA",

2468

#elif GNUTLS_VERSION_NUMBER < 0x030600

2469

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

2470

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

2471

#else

2472

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

2473

#endif

2474

.current_server = NULL, .interfaces = NULL,

2475

.interfaces_size = 0 };

1805

2476

AvahiSServiceBrowser *sb = NULL;

1806

2477

error_t ret_errno;

1807

2478

int ret;

1810

2481

int exitcode = EXIT_SUCCESS;

1811

2482

char *interfaces_to_take_down = NULL;

1812

2483

size_t interfaces_to_take_down_size = 0;

1813

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

1814

bool tempdir_created = false;

2484

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

2485

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

2486

char *tempdir = NULL;

1815

2487

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1816

2488

const char *seckey = PATHDIR "/" SECKEY;

1817

2489

const char *pubkey = PATHDIR "/" PUBKEY;

2490

#if GNUTLS_VERSION_NUMBER >= 0x030606

2491

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2492

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2493

#endif

2494

const char *dh_params_file = NULL;

1818

2495

char *interfaces_hooks = NULL;

1819

2496

1820

2497

bool gnutls_initialized = false;

1867

2544

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

1868

2545

.arg = "FILE",

1869

2546

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

1870

.group = 2 },

2547

.group = 1 },

2548

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

2549

.arg = "FILE",

2550

#if GNUTLS_VERSION_NUMBER >= 0x030606

2551

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

2552

#else

2553

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

2554

#endif

2555

.group = 1 },

2556

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

2557

.arg = "FILE",

2558

#if GNUTLS_VERSION_NUMBER >= 0x030606

2559

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

2560

#else

2561

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

2562

#endif

2563

.group = 1 },

1871

2564

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

1872

2565

.arg = "BITS",

1873

2566

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

1874

2567

" Diffie-Hellman key exchange",

1875

2568

.group = 2 },

2569

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

2570

.arg = "FILE",

2571

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

2572

" for the Diffie-Hellman key exchange",

2573

.group = 2 },

1876

2574

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

1877

2575

.arg = "STRING",

1878

2576

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

1924

2622

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

1925

2623

pubkey = arg;

1926

2624

break;

2625

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

2626

#if GNUTLS_VERSION_NUMBER >= 0x030606

2627

tls_privkey = arg;

2628

#endif

2629

break;

2630

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

2631

#if GNUTLS_VERSION_NUMBER >= 0x030606

2632

tls_pubkey = arg;

2633

#endif

2634

break;

1927

2635

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

1928

2636

errno = 0;

1929

2637

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

1933

2641

}

1934

2642

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

1935

2643

break;

2644

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

2645

dh_params_file = arg;

2646

break;

1936

2647

case 130: /* --priority */

1937

2648

mc.priority = arg;

1938

2649

break;

1961

2672

argp_state_help(state, state->out_stream,

1962

2673

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1963

2674

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2675

__builtin_unreachable();

1964

2676

case -3: /* --usage */

1965

2677

argp_state_help(state, state->out_stream,

1966

2678

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2679

__builtin_unreachable();

1967

2680

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

1968

2681

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

1969

2682

exit(argp_err_exit_status);

1978

2691

.args_doc = "",

1979

2692

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

1980

2693

" passwords from a Mandos server" };

1981

ret = argp_parse(&argp, argc, argv,

1982

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1983

switch(ret){

2694

ret_errno = argp_parse(&argp, argc, argv,

2695

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2696

switch(ret_errno){

1984

2697

case 0:

1985

2698

break;

1986

2699

case ENOMEM:

1987

2700

default:

1988

errno = ret;

2701

errno = ret_errno;

1989

2702

perror_plus("argp_parse");

1990

2703

exitcode = EX_OSERR;

1991

2704

goto end;

1994

2707

goto end;

1995

2708

}

1996

2709

}

1997

2710

1998

2711

{

1999

2712

/* Work around Debian bug #633582:

2000

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

2713

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

2001

2714

2002

/* Re-raise priviliges */

2003

if(raise_privileges() == 0){

2715

/* Re-raise privileges */

2716

ret = raise_privileges();

2717

if(ret != 0){

2718

errno = ret;

2719

perror_plus("Failed to raise privileges");

2720

} else {

2004

2721

struct stat st;

2005

2722

2006

2723

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

2020

2737

}

2021

2738

}

2022

2739

}

2023

TEMP_FAILURE_RETRY(close(seckey_fd));

2740

close(seckey_fd);

2024

2741

}

2025

2742

}

2026

2743

2027

2744

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

2028

2745

int pubkey_fd = open(pubkey, O_RDONLY);

2029

2746

if(pubkey_fd == -1){

2041

2758

}

2042

2759

}

2043

2760

}

2044

TEMP_FAILURE_RETRY(close(pubkey_fd));

2045

}

2046

}

2047

2761

close(pubkey_fd);

2762

}

2763

}

2764

2765

if(dh_params_file != NULL

2766

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

2767

int dhparams_fd = open(dh_params_file, O_RDONLY);

2768

if(dhparams_fd == -1){

2769

perror_plus("open");

2770

} else {

2771

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

2772

if(ret == -1){

2773

perror_plus("fstat");

2774

} else {

2775

if(S_ISREG(st.st_mode)

2776

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

2777

ret = fchown(dhparams_fd, uid, gid);

2778

if(ret == -1){

2779

perror_plus("fchown");

2780

}

2781

}

2782

}

2783

close(dhparams_fd);

2784

}

2785

}

2786

2048

2787

/* Lower privileges */

2049

lower_privileges();

2788

ret = lower_privileges();

2789

if(ret != 0){

2790

errno = ret;

2791

perror_plus("Failed to lower privileges");

2792

}

2050

2793

}

2051

2794

}

2052

2795

2078

2821

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

2079

2822

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

2080

2823

}

2081

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

2082

interfaces_hooks : "", delay)){

2083

goto end;

2084

}

2824

run_network_hooks("start", interfaces_hooks != NULL ?

2825

interfaces_hooks : "", delay);

2085

2826

}

2086

2827

2087

2828

if(not debug){

2165

2906

2166

2907

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

2167

2908

if(mc.interfaces == NULL){

2168

struct dirent **direntries;

2909

struct dirent **direntries = NULL;

2169

2910

/* Look for any good interfaces */

2170

2911

ret = scandir(sys_class_net, &direntries, good_interface,

2171

2912

alphasort);

2177

2918

if(ret_errno != 0){

2178

2919

errno = ret_errno;

2179

2920

perror_plus("argz_add");

2921

free(direntries[i]);

2180

2922

continue;

2181

2923

}

2182

2924

if(debug){

2183

2925

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

2184

2926

direntries[i]->d_name);

2185

2927

}

2928

free(direntries[i]);

2186

2929

}

2187

2930

free(direntries);

2188

2931

} else {

2189

free(direntries);

2932

if(ret == 0){

2933

free(direntries);

2934

}

2190

2935

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

2191

2936

exitcode = EXIT_FAILURE;

2192

2937

goto end;

2215

2960

break;

2216

2961

}

2217

2962

bool interface_was_up = interface_is_up(interface);

2218

ret = bring_up_interface(interface, delay);

2963

errno = bring_up_interface(interface, delay);

2219

2964

if(not interface_was_up){

2220

if(ret != 0){

2221

errno = ret;

2222

perror_plus("Failed to bring up interface");

2965

if(errno != 0){

2966

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

2967

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

2223

2968

} else {

2224

ret_errno = argz_add(&interfaces_to_take_down,

2225

&interfaces_to_take_down_size,

2226

interface);

2227

if(ret_errno != 0){

2228

errno = ret_errno;

2969

errno = argz_add(&interfaces_to_take_down,

2970

&interfaces_to_take_down_size,

2971

interface);

2972

if(errno != 0){

2229

2973

perror_plus("argz_add");

2230

2974

}

2231

2975

}

2249

2993

goto end;

2250

2994

}

2251

2995

2252

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

2996

#if GNUTLS_VERSION_NUMBER >= 0x030606

2997

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

2998

#elif GNUTLS_VERSION_NUMBER < 0x030600

2999

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

3000

#else

3001

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

3002

#endif

2253

3003

if(ret == -1){

2254

3004

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

2255

3005

exitcode = EX_UNAVAILABLE;

2262

3012

goto end;

2263

3013

}

2264

3014

2265

if(mkdtemp(tempdir) == NULL){

3015

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

3016

tempdir = mkdtemp(run_tempdir);

3017

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

3018

if(debug){

3019

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

3020

run_tempdir, old_tempdir);

3021

}

3022

tempdir = mkdtemp(old_tempdir);

3023

}

3024

if(tempdir == NULL){

2266

3025

perror_plus("mkdtemp");

2267

3026

goto end;

2268

3027

}

2269

tempdir_created = true;

2270

3028

2271

3029

if(quit_now){

2272

3030

goto end;

2347

3105

sleep((unsigned int)retry_interval);

2348

3106

}

2349

3107

2350

if (not quit_now){

3108

if(not quit_now){

2351

3109

exitcode = EXIT_SUCCESS;

2352

3110

}

2353

3111

2369

3127

2370

3128

/* Allocate a new server */

2371

3129

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2372

&config, NULL, NULL, &ret_errno);

3130

&config, NULL, NULL, &ret);

2373

3131

2374

3132

/* Free the Avahi configuration data */

2375

3133

avahi_server_config_free(&config);

2378

3136

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

2379

3137

if(mc.server == NULL){

2380

3138

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

2381

avahi_strerror(ret_errno));

3139

avahi_strerror(ret));

2382

3140

exitcode = EX_UNAVAILABLE;

2383

3141

goto end;

2384

3142

}

2408

3166

if(debug){

2409

3167

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

2410

3168

}

2411

3169

2412

3170

ret = avahi_loop_with_timeout(simple_poll,

2413

3171

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

2414

3172

if(debug){

2419

3177

end:

2420

3178

2421

3179

if(debug){

2422

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

3180

if(signal_received){

3181

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

3182

argv[0], signal_received,

3183

strsignal(signal_received));

3184

} else {

3185

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

3186

}

2423

3187

}

2424

3188

2425

3189

/* Cleanup things */

2436

3200

2437

3201

if(gnutls_initialized){

2438

3202

gnutls_certificate_free_credentials(mc.cred);

2439

gnutls_global_deinit();

2440

3203

gnutls_dh_params_deinit(mc.dh_params);

2441

3204

}

2442

3205

2450

3213

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

2451

3214

while(mc.current_server != NULL){

2452

3215

server *next = mc.current_server->next;

3216

#ifdef __GNUC__

3217

#pragma GCC diagnostic push

3218

#pragma GCC diagnostic ignored "-Wcast-qual"

3219

#endif

3220

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

3221

#ifdef __GNUC__

3222

#pragma GCC diagnostic pop

3223

#endif

2453

3224

free(mc.current_server);

2454

3225

mc.current_server = next;

2455

3226

}

2456

3227

}

2457

3228

2458

/* Re-raise priviliges */

3229

/* Re-raise privileges */

2459

3230

{

2460

raise_privileges();

2461

2462

/* Run network hooks */

2463

run_network_hooks("stop", interfaces_hooks != NULL ?

2464

interfaces_hooks : "", delay);

2465

2466

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

2467

{

2468

char *interface = NULL;

2469

while((interface=argz_next(interfaces_to_take_down,

2470

interfaces_to_take_down_size,

2471

interface))){

2472

ret_errno = take_down_interface(interface);

2473

if(ret_errno != 0){

2474

errno = ret_errno;

2475

perror_plus("Failed to take down interface");

2476

}

2477

}

2478

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

2479

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

2480

" down\n");

2481

}

2482

}

2483

2484

lower_privileges_permanently();

3231

ret = raise_privileges();

3232

if(ret != 0){

3233

errno = ret;

3234

perror_plus("Failed to raise privileges");

3235

} else {

3236

3237

/* Run network hooks */

3238

run_network_hooks("stop", interfaces_hooks != NULL ?

3239

interfaces_hooks : "", delay);

3240

3241

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

3242

{

3243

char *interface = NULL;

3244

while((interface = argz_next(interfaces_to_take_down,

3245

interfaces_to_take_down_size,

3246

interface))){

3247

ret = take_down_interface(interface);

3248

if(ret != 0){

3249

errno = ret;

3250

perror_plus("Failed to take down interface");

3251

}

3252

}

3253

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

3254

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

3255

" down\n");

3256

}

3257

}

3258

}

3259

3260

ret = lower_privileges_permanently();

3261

if(ret != 0){

3262

errno = ret;

3263

perror_plus("Failed to lower privileges permanently");

3264

}

2485

3265

}

2486

3266

2487

3267

free(interfaces_to_take_down);

2488

3268

free(interfaces_hooks);

2489

3269

3270

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

3271

uintmax_t level){

3272

struct dirent **direntries = NULL;

3273

int dret;

3274

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

3275

O_RDONLY

3276

| O_NOFOLLOW

3277

| O_DIRECTORY

3278

| O_PATH));

3279

if(dir_fd == -1){

3280

perror_plus("open");

3281

return;

3282

}

3283

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

3284

notdotentries, alphasort);

3285

if(numentries >= 0){

3286

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

3287

if(debug){

3288

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

3289

dirname, direntries[i]->d_name);

3290

}

3291

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

3292

if(dret == -1){

3293

if(errno == EISDIR){

3294

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

3295

AT_REMOVEDIR);

3296

}

3297

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

3298

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

3299

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

3300

/* Recurse only in this special case */

3301

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

3302

dret = 0;

3303

}

3304

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

3305

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

3306

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

3307

}

3308

}

3309

free(direntries[i]);

3310

}

3311

3312

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

3313

free(direntries);

3314

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3315

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

3316

perror_plus("rmdir");

3317

}

3318

} else {

3319

perror_plus("scandirat");

3320

}

3321

close(dir_fd);

3322

}

3323

2490

3324

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

2491

if(tempdir_created){

2492

struct dirent **direntries = NULL;

2493

struct dirent *direntry = NULL;

2494

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

2495

alphasort);

2496

if (numentries > 0){

2497

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

2498

direntry = direntries[i];

2499

char *fullname = NULL;

2500

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

2501

direntry->d_name);

2502

if(ret < 0){

2503

perror_plus("asprintf");

2504

continue;

2505

}

2506

ret = remove(fullname);

2507

if(ret == -1){

2508

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

2509

strerror(errno));

2510

}

2511

free(fullname);

2512

}

2513

}

2514

2515

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

2516

free(direntries);

2517

if (numentries == -1){

2518

perror_plus("scandir");

2519

}

2520

ret = rmdir(tempdir);

2521

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

2522

perror_plus("rmdir");

2523

}

3325

if(tempdir != NULL){

3326

clean_dir_at(-1, tempdir, 0);

2524

3327

}

2525

3328

2526

3329

if(quit_now){