/mandos/trunk : revision 618

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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 */

50

#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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61

*/

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

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63

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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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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184

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

207

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* "buffer_length" is how much is already used.

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197

*/

209

__attribute__((nonnull, warn_unused_result))

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198

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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}

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

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__attribute__((nonnull, warn_unused_result))

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211

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

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int af, server **current_server){

231

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int ret;

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222

.af = af };

241

223

if(new_server->ip == NULL){

242

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perror_plus("strdup");

243

free(new_server);

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return false;

245

}

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

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#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

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

254

#ifdef __GNUC__

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#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

225

return false;

259

226

}

260

227

/* Special case of first server */

262

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new_server->next = new_server;

263

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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 */

267

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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;

270

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(*current_server)->prev = new_server;

271

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

272

244

return true;

273

245

}

274

246

275

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

276

__attribute__((warn_unused_result))

277

int raise_privileges(void){

278

int old_errno = errno;

279

int ret = 0;

280

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

281

ret = errno;

282

}

283

errno = old_errno;

284

return ret;

285

}

286

287

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

288

__attribute__((warn_unused_result))

289

int raise_privileges_permanently(void){

290

int old_errno = errno;

291

int ret = raise_privileges();

292

if(ret != 0){

293

errno = old_errno;

294

return ret;

295

}

296

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

297

ret = errno;

298

}

299

errno = old_errno;

300

return ret;

301

}

302

303

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

304

__attribute__((warn_unused_result))

305

int lower_privileges(void){

306

int old_errno = errno;

307

int ret = 0;

308

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

309

ret = errno;

310

}

311

errno = old_errno;

312

return ret;

313

}

314

315

/* Lower privileges permanently */

316

__attribute__((warn_unused_result))

317

int lower_privileges_permanently(void){

318

int old_errno = errno;

319

int ret = 0;

320

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

321

ret = errno;

322

}

323

errno = old_errno;

324

return ret;

325

}

326

327

247

/*

328

248

* Initialize GPGME.

329

249

*/

330

__attribute__((nonnull, warn_unused_result))

331

static bool init_gpgme(const char * const seckey,

332

const char * const pubkey,

333

const char * const tempdir,

334

mandos_context *mc){

250

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

251

const char *tempdir, mandos_context *mc){

335

252

gpgme_error_t rc;

336

253

gpgme_engine_info_t engine_info;

337

254

338

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/*

339

256

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

340

257

*/

341

bool import_key(const char * const filename){

258

bool import_key(const char *filename){

342

259

int ret;

343

260

int fd;

344

261

gpgme_data_t pgp_data;

349

266

return false;

350

267

}

351

268

352

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

353

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

354

do {

355

{

356

time_t currtime = time(NULL);

357

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

358

struct tm tm;

359

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

360

perror_plus("gmtime_r");

361

break;

362

}

363

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

364

break;

365

}

366

if(debug){

367

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

368

}

369

} else {

370

if(debug){

371

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

372

}

373

}

374

}

375

struct stat keystat;

376

ret = fstat(fd, &keystat);

377

if(ret != 0){

378

perror_plus("fstat");

379

break;

380

}

381

ret = raise_privileges();

382

if(ret != 0){

383

errno = ret;

384

perror_plus("Failed to raise privileges");

385

break;

386

}

387

if(debug){

388

fprintf_plus(stderr,

389

"Setting system clock to key file mtime");

390

}

391

time_t keytime = keystat.st_mtim.tv_sec;

392

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

393

perror_plus("stime");

394

}

395

ret = lower_privileges();

396

if(ret != 0){

397

errno = ret;

398

perror_plus("Failed to lower privileges");

399

}

400

} while(false);

401

402

269

rc = gpgme_data_new_from_fd(&pgp_data, fd);

403

270

if(rc != GPG_ERR_NO_ERROR){

404

271

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

412

279

gpgme_strsource(rc), gpgme_strerror(rc));

413

280

return false;

414

281

}

415

{

416

gpgme_import_result_t import_result

417

= gpgme_op_import_result(mc->ctx);

418

if((import_result->imported < 1

419

or import_result->not_imported > 0)

420

and import_result->unchanged == 0){

421

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

422

fprintf_plus(stderr,

423

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

424

import_result->considered);

425

fprintf_plus(stderr,

426

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

427

import_result->no_user_id);

428

fprintf_plus(stderr,

429

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

430

import_result->imported);

431

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

432

import_result->imported_rsa);

433

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

434

import_result->unchanged);

435

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

436

import_result->new_user_ids);

437

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

438

import_result->new_sub_keys);

439

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

440

import_result->new_signatures);

441

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

442

import_result->new_revocations);

443

fprintf_plus(stderr,

444

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

445

import_result->secret_read);

446

fprintf_plus(stderr,

447

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

448

import_result->secret_imported);

449

fprintf_plus(stderr,

450

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

451

import_result->secret_unchanged);

452

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

453

import_result->not_imported);

454

for(gpgme_import_status_t import_status

455

= import_result->imports;

456

import_status != NULL;

457

import_status = import_status->next){

458

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

459

import_status->fpr);

460

if(import_status->result != GPG_ERR_NO_ERROR){

461

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

462

gpgme_strsource(import_status->result),

463

gpgme_strerror(import_status->result));

464

}

465

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

466

fprintf_plus(stderr,

467

import_status->status & GPGME_IMPORT_NEW

468

? "The key was new.\n"

469

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

470

fprintf_plus(stderr,

471

import_status->status & GPGME_IMPORT_UID

472

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

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_SIG

476

? "The key contained new signatures.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_SUBKEY

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SECRET

484

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

485

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

486

}

487

return false;

488

}

489

}

490

282

491

ret = close(fd);

283

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

492

284

if(ret == -1){

493

285

perror_plus("close");

494

286

}

533

325

/* Create new GPGME "context" */

534

326

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

535

327

if(rc != GPG_ERR_NO_ERROR){

536

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

537

gpgme_strsource(rc), gpgme_strerror(rc));

328

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

329

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

330

gpgme_strerror(rc));

538

331

return false;

539

332

}

540

333

549

342

* Decrypt OpenPGP data.

550

343

* Returns -1 on error

551

344

*/

552

__attribute__((nonnull, warn_unused_result))

553

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

554

346

size_t crypto_size,

555

347

char **plaintext,

576

368

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

577

369

rc = gpgme_data_new(&dh_plain);

578

370

if(rc != GPG_ERR_NO_ERROR){

579

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

371

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

372

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

580

373

gpgme_strsource(rc), gpgme_strerror(rc));

581

374

gpgme_data_release(dh_crypto);

582

375

return -1;

595

388

if(result == NULL){

596

389

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

597

390

} else {

598

if(result->unsupported_algorithm != NULL) {

599

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

600

result->unsupported_algorithm);

601

}

602

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

603

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

391

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

392

result->unsupported_algorithm);

393

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

394

result->wrong_key_usage);

604

395

if(result->file_name != NULL){

605

396

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

606

397

}

607

608

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

609

r = r->next){

398

gpgme_recipient_t recipient;

399

recipient = result->recipients;

400

while(recipient != NULL){

610

401

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

611

gpgme_pubkey_algo_name(r->pubkey_algo));

612

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

402

gpgme_pubkey_algo_name

403

(recipient->pubkey_algo));

404

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

613

405

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

614

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

408

recipient = recipient->next;

615

409

}

616

410

}

617

411

}

673

467

return plaintext_length;

674

468

}

675

469

676

__attribute__((warn_unused_result, const))

677

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

678

if(str == NULL)

679

return "(unknown)";

680

return str;

681

}

682

683

__attribute__((warn_unused_result))

684

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

685

471

const char *ret = gnutls_strerror(value);

686

return safe_string(ret);

472

if(ret == NULL)

473

ret = "(unknown)";

474

return ret;

687

475

}

688

476

689

477

/* GnuTLS log function callback */

690

__attribute__((nonnull))

691

478

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

692

479

const char* string){

693

480

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

694

481

}

695

482

696

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

697

483

static int init_gnutls_global(const char *pubkeyfilename,

698

484

const char *seckeyfilename,

699

const char *dhparamsfilename,

700

485

mandos_context *mc){

701

486

int ret;

702

unsigned int uret;

703

487

704

488

if(debug){

705

489

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

706

490

}

707

491

492

ret = gnutls_global_init();

493

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

496

return -1;

497

}

498

708

499

if(debug){

709

500

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

710

501

* - GnuTLS manual

718

509

if(ret != GNUTLS_E_SUCCESS){

719

510

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

720

511

safer_gnutls_strerror(ret));

512

gnutls_global_deinit();

721

513

return -1;

722

514

}

723

515

748

540

safer_gnutls_strerror(ret));

749

541

goto globalfail;

750

542

}

751

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

752

if(dhparamsfilename != NULL){

753

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

754

do {

755

int dhpfile = open(dhparamsfilename, O_RDONLY);

756

if(dhpfile == -1){

757

perror_plus("open");

758

dhparamsfilename = NULL;

759

break;

760

}

761

size_t params_capacity = 0;

762

while(true){

763

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

764

(size_t)params.size,

765

(size_t)params_capacity);

766

if(params_capacity == 0){

767

perror_plus("incbuffer");

768

free(params.data);

769

params.data = NULL;

770

dhparamsfilename = NULL;

771

break;

772

}

773

ssize_t bytes_read = read(dhpfile,

774

params.data + params.size,

775

BUFFER_SIZE);

776

/* EOF */

777

if(bytes_read == 0){

778

break;

779

}

780

/* check bytes_read for failure */

781

if(bytes_read < 0){

782

perror_plus("read");

783

free(params.data);

784

params.data = NULL;

785

dhparamsfilename = NULL;

786

break;

787

}

788

params.size += (unsigned int)bytes_read;

789

}

790

ret = close(dhpfile);

791

if(ret == -1){

792

perror_plus("close");

793

}

794

if(params.data == NULL){

795

dhparamsfilename = NULL;

796

}

797

if(dhparamsfilename == NULL){

798

break;

799

}

800

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

801

GNUTLS_X509_FMT_PEM);

802

if(ret != GNUTLS_E_SUCCESS){

803

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

804

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

805

safer_gnutls_strerror(ret));

806

dhparamsfilename = NULL;

807

}

808

free(params.data);

809

} while(false);

810

}

811

if(dhparamsfilename == NULL){

812

if(mc->dh_bits == 0){

813

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

814

/* Try to read the private key file */

815

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

816

do {

817

int secfile = open(seckeyfilename, O_RDONLY);

818

if(secfile == -1){

819

perror_plus("open");

820

break;

821

}

822

size_t buffer_capacity = 0;

823

while(true){

824

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

825

(size_t)buffer.size,

826

(size_t)buffer_capacity);

827

if(buffer_capacity == 0){

828

perror_plus("incbuffer");

829

free(buffer.data);

830

buffer.data = NULL;

831

break;

832

}

833

ssize_t bytes_read = read(secfile,

834

buffer.data + buffer.size,

835

BUFFER_SIZE);

836

/* EOF */

837

if(bytes_read == 0){

838

break;

839

}

840

/* check bytes_read for failure */

841

if(bytes_read < 0){

842

perror_plus("read");

843

free(buffer.data);

844

buffer.data = NULL;

845

break;

846

}

847

buffer.size += (unsigned int)bytes_read;

848

}

849

close(secfile);

850

} while(false);

851

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

852

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

853

if(buffer.data != NULL){

854

{

855

gnutls_openpgp_privkey_t privkey = NULL;

856

ret = gnutls_openpgp_privkey_init(&privkey);

857

if(ret != GNUTLS_E_SUCCESS){

858

fprintf_plus(stderr, "Error initializing OpenPGP key"

859

" structure: %s",

860

safer_gnutls_strerror(ret));

861

free(buffer.data);

862

buffer.data = NULL;

863

} else {

864

ret = gnutls_openpgp_privkey_import

865

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

866

if(ret != GNUTLS_E_SUCCESS){

867

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

868

safer_gnutls_strerror(ret));

869

privkey = NULL;

870

}

871

free(buffer.data);

872

buffer.data = NULL;

873

if(privkey != NULL){

874

/* Use private key to suggest an appropriate

875

sec_param */

876

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

877

gnutls_openpgp_privkey_deinit(privkey);

878

if(debug){

879

fprintf_plus(stderr, "This OpenPGP key implies using"

880

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

881

safe_string(gnutls_sec_param_get_name

882

(sec_param)));

883

}

884

}

885

}

886

}

887

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

888

/* Err on the side of caution */

889

sec_param = GNUTLS_SEC_PARAM_ULTRA;

890

if(debug){

891

fprintf_plus(stderr, "Falling back to security parameter"

892

" \"%s\"\n",

893

safe_string(gnutls_sec_param_get_name

894

(sec_param)));

895

}

896

}

897

}

898

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

899

if(uret != 0){

900

mc->dh_bits = uret;

901

if(debug){

902

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

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)),

906

mc->dh_bits);

907

}

908

} else {

909

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

910

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

911

safe_string(gnutls_sec_param_get_name

912

(sec_param)),

913

safer_gnutls_strerror(ret));

914

goto globalfail;

915

}

916

} else if(debug){

917

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

918

mc->dh_bits);

919

}

920

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

921

if(ret != GNUTLS_E_SUCCESS){

922

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

923

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

924

safer_gnutls_strerror(ret));

925

goto globalfail;

926

}

927

}

543

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

544

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

547

goto globalfail;

548

}

549

928

550

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

929

551

930

552

return 0;

932

554

globalfail:

933

555

934

556

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_global_deinit();

935

558

gnutls_dh_params_deinit(mc->dh_params);

936

559

return -1;

937

560

}

938

561

939

__attribute__((nonnull, warn_unused_result))

940

562

static int init_gnutls_session(gnutls_session_t *session,

941

563

mandos_context *mc){

942

564

int ret;

989

611

/* ignore client certificate if any. */

990

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

991

613

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

615

992

616

return 0;

993

617

}

994

618

996

620

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

997

621

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

998

622

999

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

1000

__attribute__((nonnull, warn_unused_result))

1001

static bool add_delete_local_route(const bool add,

1002

const char *address,

1003

AvahiIfIndex if_index){

1004

int ret;

1005

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

1006

char add_arg[] = "add";

1007

char delete_arg[] = "delete";

1008

char debug_flag[] = "--debug";

1009

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1010

if(pluginhelperdir == NULL){

1011

if(debug){

1012

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1013

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

1014

}

1015

return false;

1016

}

1017

1018

char interface[IF_NAMESIZE];

1019

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

1020

perror_plus("if_indextoname");

1021

return false;

1022

}

1023

1024

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

1025

if(devnull == -1){

1026

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

1027

return false;

1028

}

1029

pid_t pid = fork();

1030

if(pid == 0){

1031

/* Child */

1032

/* Raise privileges */

1033

errno = raise_privileges_permanently();

1034

if(errno != 0){

1035

perror_plus("Failed to raise privileges");

1036

/* _exit(EX_NOPERM); */

1037

} else {

1038

/* Set group */

1039

errno = 0;

1040

ret = setgid(0);

1041

if(ret == -1){

1042

perror_plus("setgid");

1043

_exit(EX_NOPERM);

1044

}

1045

/* Reset supplementary groups */

1046

errno = 0;

1047

ret = setgroups(0, NULL);

1048

if(ret == -1){

1049

perror_plus("setgroups");

1050

_exit(EX_NOPERM);

1051

}

1052

}

1053

ret = dup2(devnull, STDIN_FILENO);

1054

if(ret == -1){

1055

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

1056

_exit(EX_OSERR);

1057

}

1058

ret = close(devnull);

1059

if(ret == -1){

1060

perror_plus("close");

1061

_exit(EX_OSERR);

1062

}

1063

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1064

if(ret == -1){

1065

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

1066

_exit(EX_OSERR);

1067

}

1068

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

1069

O_RDONLY

1070

| O_DIRECTORY

1071

| O_PATH

1072

| O_CLOEXEC));

1073

if(helperdir_fd == -1){

1074

perror_plus("open");

1075

_exit(EX_UNAVAILABLE);

1076

}

1077

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

1078

helper, O_RDONLY));

1079

if(helper_fd == -1){

1080

perror_plus("openat");

1081

close(helperdir_fd);

1082

_exit(EX_UNAVAILABLE);

1083

}

1084

close(helperdir_fd);

1085

#ifdef __GNUC__

1086

#pragma GCC diagnostic push

1087

#pragma GCC diagnostic ignored "-Wcast-qual"

1088

#endif

1089

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

1090

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

1091

interface, debug ? debug_flag : NULL, NULL },

1092

environ) == -1){

1093

#ifdef __GNUC__

1094

#pragma GCC diagnostic pop

1095

#endif

1096

perror_plus("fexecve");

1097

_exit(EXIT_FAILURE);

1098

}

1099

}

1100

if(pid == -1){

1101

perror_plus("fork");

1102

return false;

1103

}

1104

int status;

1105

pid_t pret = -1;

1106

errno = 0;

1107

do {

1108

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

1109

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

1110

int errno_raising = 0;

1111

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

1112

errno_raising = errno;

1113

perror_plus("Failed to raise privileges in order to"

1114

" kill helper program");

1115

}

1116

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

1117

perror_plus("kill");

1118

}

1119

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

1120

perror_plus("Failed to lower privileges after killing"

1121

" helper program");

1122

}

1123

return false;

1124

}

1125

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

1126

if(pret == -1){

1127

perror_plus("waitpid");

1128

return false;

1129

}

1130

if(WIFEXITED(status)){

1131

if(WEXITSTATUS(status) != 0){

1132

fprintf_plus(stderr, "Error: iprouteadddel exited"

1133

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

1134

return false;

1135

}

1136

return true;

1137

}

1138

if(WIFSIGNALED(status)){

1139

fprintf_plus(stderr, "Error: iprouteadddel died by"

1140

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

1141

return false;

1142

}

1143

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

1144

return false;

1145

}

1146

1147

__attribute__((nonnull, warn_unused_result))

1148

static bool add_local_route(const char *address,

1149

AvahiIfIndex if_index){

1150

if(debug){

1151

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

1152

}

1153

return add_delete_local_route(true, address, if_index);

1154

}

1155

1156

__attribute__((nonnull, warn_unused_result))

1157

static bool delete_local_route(const char *address,

1158

AvahiIfIndex if_index){

1159

if(debug){

1160

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

1161

}

1162

return add_delete_local_route(false, address, if_index);

1163

}

1164

1165

623

/* Called when a Mandos server is found */

1166

__attribute__((nonnull, warn_unused_result))

1167

624

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

1168

625

AvahiIfIndex if_index,

1169

626

int af, mandos_context *mc){

1170

627

int ret, tcp_sd = -1;

1171

628

ssize_t sret;

1172

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1173

633

char *buffer = NULL;

1174

634

char *decrypted_buffer = NULL;

1175

635

size_t buffer_length = 0;

1178

638

int retval = -1;

1179

639

gnutls_session_t session;

1180

640

int pf; /* Protocol family */

1181

bool route_added = false;

1182

641

1183

642

errno = 0;

1184

643

1206

665

bool match = false;

1207

666

{

1208

667

char *interface = NULL;

1209

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

1210

mc->interfaces_size,

1211

interface))){

668

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

669

interface))){

1212

670

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

1213

671

match = true;

1214

672

break;

1243

701

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

1244

702

}

1245

703

1246

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

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

1247

705

if(tcp_sd < 0){

1248

706

int e = errno;

1249

707

perror_plus("socket");

1256

714

goto mandos_end;

1257

715

}

1258

716

717

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

1259

718

if(af == AF_INET6){

1260

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

1261

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

1262

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

719

to.in6.sin6_family = (sa_family_t)af;

720

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

1263

721

} else { /* IPv4 */

1264

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

1265

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

1266

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

722

to.in.sin_family = (sa_family_t)af;

723

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

1267

724

}

1268

725

if(ret < 0 ){

1269

726

int e = errno;

1278

735

goto mandos_end;

1279

736

}

1280

737

if(af == AF_INET6){

1281

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

1282

if(IN6_IS_ADDR_LINKLOCAL

1283

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

738

to.in6.sin6_port = htons(port);

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

740

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

741

-Wunreachable-code*/

1284

742

if(if_index == AVAHI_IF_UNSPEC){

1285

743

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

1286

744

" incomplete without a network interface\n");

1288

746

goto mandos_end;

1289

747

}

1290

748

/* Set the network interface number as scope */

1291

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

749

to.in6.sin6_scope_id = (uint32_t)if_index;

1292

750

}

1293

751

} else {

1294

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

752

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

753

-Wconversion and

754

-Wunreachable-code */

1295

755

}

1296

756

1297

757

if(quit_now){

1314

774

}

1315

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1316

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1317

if(af == AF_INET6){

1318

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

1319

sizeof(struct sockaddr_in6),

1320

addrstr, sizeof(addrstr), NULL, 0,

1321

NI_NUMERICHOST);

1322

} else {

1323

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

1324

sizeof(struct sockaddr_in),

1325

addrstr, sizeof(addrstr), NULL, 0,

1326

NI_NUMERICHOST);

1327

}

1328

if(ret == EAI_SYSTEM){

1329

perror_plus("getnameinfo");

1330

} else if(ret != 0) {

1331

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

1332

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

1333

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

1334

}

1335

}

1336

1337

if(quit_now){

1338

errno = EINTR;

1339

goto mandos_end;

1340

}

1341

1342

while(true){

1343

if(af == AF_INET6){

1344

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

1345

sizeof(struct sockaddr_in6));

1346

} else {

1347

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

1348

sizeof(struct sockaddr_in));

1349

}

1350

if(ret < 0){

1351

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

1352

and if_index != AVAHI_IF_UNSPEC

1353

and connect_to == NULL

1354

and not route_added and

1355

((af == AF_INET6 and not

1356

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1357

&to)->sin6_addr)))

1358

or (af == AF_INET and

1359

/* Not a a IPv4LL address */

1360

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

1361

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

1362

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

1363

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

1364

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

1365

connect to a Mandos server announced by Avahi on a server

1366

host with a global address. Work around this by retrying

1367

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

1368

1369

Avahi bug reference:

1370

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

1371

https://bugs.debian.org/587961

1372

*/

1373

if(debug){

1374

fprintf_plus(stderr, "Mandos server unreachable, trying"

1375

" direct route\n");

1376

}

1377

int e = errno;

1378

route_added = add_local_route(ip, if_index);

1379

if(route_added){

1380

continue;

1381

}

1382

errno = e;

1383

}

1384

if(errno != ECONNREFUSED or debug){

1385

int e = errno;

1386

perror_plus("connect");

1387

errno = e;

1388

}

1389

goto mandos_end;

1390

}

1391

1392

if(quit_now){

1393

errno = EINTR;

1394

goto mandos_end;

1395

}

1396

break;

777

const char *pcret;

778

if(af == AF_INET6){

779

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

780

sizeof(addrstr));

781

} else {

782

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

783

sizeof(addrstr));

784

}

785

if(pcret == NULL){

786

perror_plus("inet_ntop");

787

} else {

788

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

789

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

790

}

791

}

792

}

793

794

if(quit_now){

795

errno = EINTR;

796

goto mandos_end;

797

}

798

799

if(af == AF_INET6){

800

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

801

} else {

802

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

803

}

804

if(ret < 0){

805

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

806

int e = errno;

807

perror_plus("connect");

808

errno = e;

809

}

810

goto mandos_end;

811

}

812

813

if(quit_now){

814

errno = EINTR;

815

goto mandos_end;

1397

816

}

1398

817

1399

818

const char *out = mandos_protocol_version;

1553

972

&decrypted_buffer, mc);

1554

973

if(decrypted_buffer_size >= 0){

1555

974

1556

clearerr(stdout);

1557

975

written = 0;

1558

976

while(written < (size_t) decrypted_buffer_size){

1559

977

if(quit_now){

1575

993

}

1576

994

written += (size_t)ret;

1577

995

}

1578

ret = fflush(stdout);

1579

if(ret != 0){

1580

int e = errno;

1581

if(debug){

1582

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

1583

strerror(errno));

1584

}

1585

errno = e;

1586

goto mandos_end;

1587

}

1588

996

retval = 0;

1589

997

}

1590

998

}

1593

1001

1594

1002

mandos_end:

1595

1003

{

1596

if(route_added){

1597

if(not delete_local_route(ip, if_index)){

1598

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

1599

" interface %d", ip, if_index);

1600

}

1601

}

1602

1004

int e = errno;

1603

1005

free(decrypted_buffer);

1604

1006

free(buffer);

1605

1007

if(tcp_sd >= 0){

1606

ret = close(tcp_sd);

1008

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

1607

1009

}

1608

1010

if(ret == -1){

1609

1011

if(e == 0){

1634

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

1635

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1636

1038

flags,

1637

void *mc){

1039

void* mc){

1638

1040

if(r == NULL){

1639

1041

return;

1640

1042

}

1643

1045

timed out */

1644

1046

1645

1047

if(quit_now){

1646

avahi_s_service_resolver_free(r);

1647

1048

return;

1648

1049

}

1649

1050

1694

1095

const char *domain,

1695

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1696

1097

flags,

1697

void *mc){

1098

void* mc){

1698

1099

if(b == NULL){

1699

1100

return;

1700

1101

}

1760

1161

errno = old_errno;

1761

1162

}

1762

1163

1763

__attribute__((nonnull, warn_unused_result))

1764

1164

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

1765

1165

int ret;

1766

int old_errno;

1166

error_t ret_errno;

1767

1167

1768

1168

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

1769

1169

if(s < 0){

1770

old_errno = errno;

1170

ret_errno = errno;

1771

1171

perror_plus("socket");

1772

errno = old_errno;

1172

errno = ret_errno;

1773

1173

return false;

1774

1174

}

1775

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

1776

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

1175

strcpy(ifr->ifr_name, ifname);

1777

1176

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1778

1177

if(ret == -1){

1779

1178

if(debug){

1780

old_errno = errno;

1179

ret_errno = errno;

1781

1180

perror_plus("ioctl SIOCGIFFLAGS");

1782

errno = old_errno;

1783

}

1784

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

1785

old_errno = errno;

1786

perror_plus("close");

1787

errno = old_errno;

1181

errno = ret_errno;

1788

1182

}

1789

1183

return false;

1790

1184

}

1791

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

1792

old_errno = errno;

1793

perror_plus("close");

1794

errno = old_errno;

1795

}

1796

1185

return true;

1797

1186

}

1798

1187

1799

__attribute__((nonnull, warn_unused_result))

1800

1188

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

1801

1189

1802

1190

/* Reject the loopback device */

1844

1232

* corresponds to an acceptable network device.

1845

1233

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

1846

1234

*/

1847

__attribute__((nonnull, warn_unused_result))

1848

1235

int good_interface(const struct dirent *if_entry){

1849

1236

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

1850

1237

return 0;

1868

1255

/*

1869

1256

* This function determines if a network interface is up.

1870

1257

*/

1871

__attribute__((nonnull, warn_unused_result))

1872

1258

bool interface_is_up(const char *interface){

1873

1259

struct ifreq ifr;

1874

1260

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

1885

1271

/*

1886

1272

* This function determines if a network interface is running

1887

1273

*/

1888

__attribute__((nonnull, warn_unused_result))

1889

1274

bool interface_is_running(const char *interface){

1890

1275

struct ifreq ifr;

1891

1276

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

1899

1284

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

1900

1285

}

1901

1286

1902

__attribute__((nonnull, pure, warn_unused_result))

1903

1287

int notdotentries(const struct dirent *direntry){

1904

1288

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

1905

1289

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

1912

1296

}

1913

1297

1914

1298

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

1915

__attribute__((nonnull, warn_unused_result))

1916

1299

int runnable_hook(const struct dirent *direntry){

1917

1300

int ret;

1918

1301

size_t sret;

1926

1309

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

1927

1310

"abcdefghijklmnopqrstuvwxyz"

1928

1311

"0123456789"

1929

"_.-");

1312

"_-");

1930

1313

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

1931

1314

/* Contains non-allowed characters */

1932

1315

if(debug){

1936

1319

return 0;

1937

1320

}

1938

1321

1939

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

1322

char *fullname = NULL;

1323

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

1324

if(ret < 0){

1325

perror_plus("asprintf");

1326

return 0;

1327

}

1328

1329

ret = stat(fullname, &st);

1940

1330

if(ret == -1){

1941

1331

if(debug){

1942

1332

perror_plus("Could not stat hook");

1966

1356

return 1;

1967

1357

}

1968

1358

1969

__attribute__((nonnull, warn_unused_result))

1970

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1971

1360

mandos_context *mc){

1972

1361

int ret;

1976

1365

1977

1366

while(true){

1978

1367

if(mc->current_server == NULL){

1979

if(debug){

1368

if (debug){

1980

1369

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

1981

1370

" No timeout!\n");

1982

1371

}

1983

1372

ret = avahi_simple_poll_iterate(s, -1);

1984

1373

} else {

1985

if(debug){

1374

if (debug){

1986

1375

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

1987

1376

" it, or wait\n");

1988

1377

}

2005

1394

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

2006

1395

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

2007

1396

2008

if(debug){

1397

if (debug){

2009

1398

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

2010

1399

block_time);

2011

1400

}

2033

1422

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

2034

1423

}

2035

1424

if(ret != 0){

2036

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

1425

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

2037

1426

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

2038

1427

}

2039

1428

}

2040

1429

}

2041

1430

}

2042

1431

2043

__attribute__((nonnull))

2044

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

1432

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

1433

error_t raise_privileges(void){

1434

error_t old_errno = errno;

1435

error_t ret_errno = 0;

1436

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

1437

ret_errno = errno;

1438

perror_plus("seteuid");

1439

}

1440

errno = old_errno;

1441

return ret_errno;

1442

}

1443

1444

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

1445

error_t raise_privileges_permanently(void){

1446

error_t old_errno = errno;

1447

error_t ret_errno = raise_privileges();

1448

if(ret_errno != 0){

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

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

1453

ret_errno = errno;

1454

perror_plus("seteuid");

1455

}

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

1460

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

1461

error_t lower_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

/* Lower privileges permanently */

1473

error_t lower_privileges_permanently(void){

1474

error_t old_errno = errno;

1475

error_t ret_errno = 0;

1476

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

1477

ret_errno = errno;

1478

perror_plus("setuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

2045

1485

const float delay){

2046

struct dirent **direntries = NULL;

2047

if(hookdir_fd == -1){

2048

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2049

| O_CLOEXEC);

2050

if(hookdir_fd == -1){

2051

if(errno == ENOENT){

2052

if(debug){

2053

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

2054

" found\n", hookdir);

2055

}

2056

} else {

2057

perror_plus("open");

2058

}

2059

return;

2060

}

2061

}

2062

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

2063

if(devnull == -1){

2064

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

2065

return;

2066

}

2067

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

2068

runnable_hook, alphasort);

1486

struct dirent **direntries;

1487

struct dirent *direntry;

1488

int ret;

1489

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

1490

alphasort);

2069

1491

if(numhooks == -1){

2070

perror_plus("scandir");

2071

close(devnull);

2072

return;

2073

}

2074

struct dirent *direntry;

2075

int ret;

2076

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

2077

direntry = direntries[i];

2078

if(debug){

2079

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

2080

direntry->d_name);

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

2081

1499

}

2082

pid_t hook_pid = fork();

2083

if(hook_pid == 0){

2084

/* Child */

2085

/* Raise privileges */

2086

errno = raise_privileges_permanently();

2087

if(errno != 0){

2088

perror_plus("Failed to raise privileges");

2089

_exit(EX_NOPERM);

2090

}

2091

/* Set group */

2092

errno = 0;

2093

ret = setgid(0);

2094

if(ret == -1){

2095

perror_plus("setgid");

2096

_exit(EX_NOPERM);

2097

}

2098

/* Reset supplementary groups */

2099

errno = 0;

2100

ret = setgroups(0, NULL);

2101

if(ret == -1){

2102

perror_plus("setgroups");

2103

_exit(EX_NOPERM);

2104

}

2105

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

2106

if(ret == -1){

2107

perror_plus("setenv");

2108

_exit(EX_OSERR);

2109

}

2110

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

2111

if(ret == -1){

2112

perror_plus("setenv");

2113

_exit(EX_OSERR);

2114

}

2115

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

2116

if(ret == -1){

2117

perror_plus("setenv");

2118

_exit(EX_OSERR);

2119

}

2120

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

2121

if(ret == -1){

2122

perror_plus("setenv");

2123

_exit(EX_OSERR);

2124

}

2125

char *delaystring;

2126

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

2127

if(ret == -1){

1500

} else {

1501

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

1502

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

1503

direntry = direntries[i];

1504

char *fullname = NULL;

1505

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

1506

if(ret < 0){

2128

1507

perror_plus("asprintf");

2129

_exit(EX_OSERR);

2130

}

2131

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

2132

if(ret == -1){

1508

continue;

1509

}

1510

if(debug){

1511

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

1512

direntry->d_name);

1513

}

1514

pid_t hook_pid = fork();

1515

if(hook_pid == 0){

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1531

dup2(devnull, STDIN_FILENO);

1532

close(devnull);

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

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

1540

if(ret == -1){

1541

perror_plus("setenv");

1542

_exit(EX_OSERR);

1543

}

1544

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

1545

if(ret == -1){

1546

perror_plus("setenv");

1547

_exit(EX_OSERR);

1548

}

1549

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

1550

if(ret == -1){

1551

perror_plus("setenv");

1552

_exit(EX_OSERR);

1553

}

1554

char *delaystring;

1555

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

1556

if(ret == -1){

1557

perror_plus("asprintf");

1558

_exit(EX_OSERR);

1559

}

1560

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

1561

if(ret == -1){

1562

free(delaystring);

1563

perror_plus("setenv");

1564

_exit(EX_OSERR);

1565

}

2133

1566

free(delaystring);

2134

perror_plus("setenv");

2135

_exit(EX_OSERR);

2136

}

2137

free(delaystring);

2138

if(connect_to != NULL){

2139

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

2140

if(ret == -1){

2141

perror_plus("setenv");

2142

_exit(EX_OSERR);

2143

}

2144

}

2145

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

2146

direntry->d_name,

2147

O_RDONLY));

2148

if(hook_fd == -1){

2149

perror_plus("openat");

2150

_exit(EXIT_FAILURE);

2151

}

2152

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

2153

perror_plus("close");

2154

_exit(EXIT_FAILURE);

2155

}

2156

ret = dup2(devnull, STDIN_FILENO);

2157

if(ret == -1){

2158

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

2159

_exit(EX_OSERR);

2160

}

2161

ret = close(devnull);

2162

if(ret == -1){

2163

perror_plus("close");

2164

_exit(EX_OSERR);

2165

}

2166

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2167

if(ret == -1){

2168

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

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

environ) == -1){

2173

perror_plus("fexecve");

2174

_exit(EXIT_FAILURE);

2175

}

2176

} else {

2177

if(hook_pid == -1){

2178

perror_plus("fork");

2179

free(direntry);

2180

continue;

2181

}

2182

int status;

2183

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

2184

perror_plus("waitpid");

2185

free(direntry);

2186

continue;

2187

}

2188

if(WIFEXITED(status)){

2189

if(WEXITSTATUS(status) != 0){

2190

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

2191

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

2192

WEXITSTATUS(status));

2193

free(direntry);

2194

continue;

2195

}

2196

} else if(WIFSIGNALED(status)){

2197

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

2198

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

2199

WTERMSIG(status));

2200

free(direntry);

2201

continue;

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

2202

1578

} else {

2203

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

2204

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

2205

free(direntry);

2206

continue;

2207

}

2208

}

2209

if(debug){

2210

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

2211

direntry->d_name);

2212

}

2213

free(direntry);

2214

}

2215

free(direntries);

2216

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

2217

perror_plus("close");

2218

} else {

2219

hookdir_fd = -1;

2220

}

2221

close(devnull);

1579

int status;

1580

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

1581

perror_plus("waitpid");

1582

free(fullname);

1583

continue;

1584

}

1585

if(WIFEXITED(status)){

1586

if(WEXITSTATUS(status) != 0){

1587

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

1588

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

1589

WEXITSTATUS(status));

1590

free(fullname);

1591

continue;

1592

}

1593

} else if(WIFSIGNALED(status)){

1594

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

1595

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

1596

WTERMSIG(status));

1597

free(fullname);

1598

continue;

1599

} else {

1600

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

1601

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

1602

free(fullname);

1603

continue;

1604

}

1605

}

1606

free(fullname);

1607

if(debug){

1608

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

1609

direntry->d_name);

1610

}

1611

}

1612

close(devnull);

1613

}

1614

return true;

2222

1615

}

2223

1616

2224

__attribute__((nonnull, warn_unused_result))

2225

int bring_up_interface(const char *const interface,

2226

const float delay){

2227

int old_errno = errno;

2228

int ret;

1617

error_t bring_up_interface(const char *const interface,

1618

const float delay){

1619

int sd = -1;

1620

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

2229

1623

struct ifreq network;

2230

1624

unsigned int if_index = if_nametoindex(interface);

2231

1625

if(if_index == 0){

2240

1634

}

2241

1635

2242

1636

if(not interface_is_up(interface)){

2243

int ret_errno = 0;

2244

int ioctl_errno = 0;

2245

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

1637

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

2246

1638

ret_errno = errno;

2247

1639

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

2248

1640

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

2249

errno = old_errno;

2250

1641

return ret_errno;

2251

1642

}

2252

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

1643

network.ifr_flags |= IFF_UP;

2253

1644

2254

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

2255

if(sd == -1){

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

2256

1647

ret_errno = errno;

2257

1648

perror_plus("socket");

2258

1649

errno = old_errno;

2259

1650

return ret_errno;

2260

1651

}

2261

1652

2262

1653

if(quit_now){

2263

ret = close(sd);

2264

if(ret == -1){

2265

perror_plus("close");

2266

}

1654

close(sd);

2267

1655

errno = old_errno;

2268

1656

return EINTR;

2269

1657

}

2273

1661

interface);

2274

1662

}

2275

1663

2276

/* Raise privileges */

2277

ret_errno = raise_privileges();

2278

if(ret_errno != 0){

2279

errno = ret_errno;

2280

perror_plus("Failed to raise privileges");

2281

}

1664

/* Raise priviliges */

1665

raise_privileges();

2282

1666

2283

1667

#ifdef __linux__

2284

int ret_linux;

2285

bool restore_loglevel = false;

2286

if(ret_errno == 0){

2287

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2288

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

2289

ret_linux = klogctl(8, NULL, 5);

2290

if(ret_linux == -1){

2291

perror_plus("klogctl");

2292

} else {

2293

restore_loglevel = true;

2294

}

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

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

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

2295

1675

}

2296

1676

#endif /* __linux__ */

2297

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

2298

ioctl_errno = errno;

1677

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

1678

ret_errno = errno;

2299

1679

#ifdef __linux__

2300

1680

if(restore_loglevel){

2301

1681

ret_linux = klogctl(7, NULL, 0);

2305

1685

}

2306

1686

#endif /* __linux__ */

2307

1687

2308

/* If raise_privileges() succeeded above */

2309

if(ret_errno == 0){

2310

/* Lower privileges */

2311

ret_errno = lower_privileges();

2312

if(ret_errno != 0){

2313

errno = ret_errno;

2314

perror_plus("Failed to lower privileges");

2315

}

2316

}

1688

/* Lower privileges */

1689

lower_privileges();

2317

1690

2318

1691

/* Close the socket */

2319

ret = close(sd);

1692

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

2320

1693

if(ret == -1){

2321

1694

perror_plus("close");

2322

1695

}

2323

1696

2324

1697

if(ret_setflags == -1){

2325

errno = ioctl_errno;

1698

errno = ret_errno;

2326

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2327

1700

errno = old_errno;

2328

return ioctl_errno;

1701

return ret_errno;

2329

1702

}

2330

1703

} else if(debug){

2331

1704

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

2334

1707

2335

1708

/* Sleep checking until interface is running.

2336

1709

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

2337

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

1710

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

2338

1711

if(interface_is_running(interface)){

2339

1712

break;

2340

1713

}

2349

1722

return 0;

2350

1723

}

2351

1724

2352

__attribute__((nonnull, warn_unused_result))

2353

int take_down_interface(const char *const interface){

2354

int old_errno = errno;

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

2355

1730

struct ifreq network;

2356

1731

unsigned int if_index = if_nametoindex(interface);

2357

1732

if(if_index == 0){

2360

1735

return ENXIO;

2361

1736

}

2362

1737

if(interface_is_up(interface)){

2363

int ret_errno = 0;

2364

int ioctl_errno = 0;

2365

1738

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

2366

1739

ret_errno = errno;

2367

1740

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

2368

1741

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

2369

errno = old_errno;

2370

1742

return ret_errno;

2371

1743

}

2372

1744

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

2373

1745

2374

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

2375

if(sd == -1){

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

2376

1748

ret_errno = errno;

2377

1749

perror_plus("socket");

2378

1750

errno = old_errno;

2384

1756

interface);

2385

1757

}

2386

1758

2387

/* Raise privileges */

2388

ret_errno = raise_privileges();

2389

if(ret_errno != 0){

2390

errno = ret_errno;

2391

perror_plus("Failed to raise privileges");

2392

}

2393

2394

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

2395

ioctl_errno = errno;

2396

2397

/* If raise_privileges() succeeded above */

2398

if(ret_errno == 0){

2399

/* Lower privileges */

2400

ret_errno = lower_privileges();

2401

if(ret_errno != 0){

2402

errno = ret_errno;

2403

perror_plus("Failed to lower privileges");

2404

}

2405

}

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

2406

1767

2407

1768

/* Close the socket */

2408

int ret = close(sd);

1769

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

2409

1770

if(ret == -1){

2410

1771

perror_plus("close");

2411

1772

}

2412

1773

2413

1774

if(ret_setflags == -1){

2414

errno = ioctl_errno;

1775

errno = ret_errno;

2415

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2416

1777

errno = old_errno;

2417

return ioctl_errno;

1778

return ret_errno;

2418

1779

}

2419

1780

} else if(debug){

2420

1781

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

2426

1787

}

2427

1788

2428

1789

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

2429

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

2430

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

2431

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

2432

.current_server = NULL, .interfaces = NULL,

2433

.interfaces_size = 0 };

1790

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

1791

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

1792

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

1793

.interfaces = NULL, .interfaces_size = 0 };

2434

1794

AvahiSServiceBrowser *sb = NULL;

2435

1795

error_t ret_errno;

2436

1796

int ret;

2439

1799

int exitcode = EXIT_SUCCESS;

2440

1800

char *interfaces_to_take_down = NULL;

2441

1801

size_t interfaces_to_take_down_size = 0;

2442

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

2443

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

2444

char *tempdir = NULL;

1802

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

1803

bool tempdir_created = false;

2445

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2446

1805

const char *seckey = PATHDIR "/" SECKEY;

2447

1806

const char *pubkey = PATHDIR "/" PUBKEY;

2448

const char *dh_params_file = NULL;

2449

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

2450

1809

2451

1810

bool gnutls_initialized = false;

2452

1811

bool gpgme_initialized = false;

2504

1863

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

2505

1864

" Diffie-Hellman key exchange",

2506

1865

.group = 2 },

2507

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

2508

.arg = "FILE",

2509

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

2510

" for the Diffie-Hellman key exchange",

2511

.group = 2 },

2512

1866

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

2513

1867

.arg = "STRING",

2514

1868

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

2569

1923

}

2570

1924

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

2571

1925

break;

2572

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

2573

dh_params_file = arg;

2574

break;

2575

1926

case 130: /* --priority */

2576

1927

mc.priority = arg;

2577

1928

break;

2617

1968

.args_doc = "",

2618

1969

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

2619

1970

" passwords from a Mandos server" };

2620

ret_errno = argp_parse(&argp, argc, argv,

2621

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2622

switch(ret_errno){

1971

ret = argp_parse(&argp, argc, argv,

1972

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1973

switch(ret){

2623

1974

case 0:

2624

1975

break;

2625

1976

case ENOMEM:

2626

1977

default:

2627

errno = ret_errno;

1978

errno = ret;

2628

1979

perror_plus("argp_parse");

2629

1980

exitcode = EX_OSERR;

2630

1981

goto end;

2633

1984

goto end;

2634

1985

}

2635

1986

}

2636

1987

2637

1988

{

2638

1989

/* Work around Debian bug #633582:

2639

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

1990

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

2640

1991

2641

/* Re-raise privileges */

2642

ret = raise_privileges();

2643

if(ret != 0){

2644

errno = ret;

2645

perror_plus("Failed to raise privileges");

2646

} else {

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2647

1994

struct stat st;

2648

1995

2649

1996

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

2663

2010

}

2664

2011

}

2665

2012

}

2666

close(seckey_fd);

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2667

2014

}

2668

2015

}

2669

2016

2670

2017

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

2671

2018

int pubkey_fd = open(pubkey, O_RDONLY);

2672

2019

if(pubkey_fd == -1){

2684

2031

}

2685

2032

}

2686

2033

}

2687

close(pubkey_fd);

2688

}

2689

}

2690

2691

if(dh_params_file != NULL

2692

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

2693

int dhparams_fd = open(dh_params_file, O_RDONLY);

2694

if(dhparams_fd == -1){

2695

perror_plus("open");

2696

} else {

2697

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

2698

if(ret == -1){

2699

perror_plus("fstat");

2700

} else {

2701

if(S_ISREG(st.st_mode)

2702

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

2703

ret = fchown(dhparams_fd, uid, gid);

2704

if(ret == -1){

2705

perror_plus("fchown");

2706

}

2707

}

2708

}

2709

close(dhparams_fd);

2710

}

2711

}

2712

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2713

2038

/* Lower privileges */

2714

ret = lower_privileges();

2715

if(ret != 0){

2716

errno = ret;

2717

perror_plus("Failed to lower privileges");

2718

}

2039

lower_privileges();

2719

2040

}

2720

2041

}

2721

2042

2745

2066

goto end;

2746

2067

}

2747

2068

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

2748

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

2749

}

2750

run_network_hooks("start", interfaces_hooks != NULL ?

2751

interfaces_hooks : "", delay);

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

2072

}

2073

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

2074

interfaces_hooks : "", delay)){

2075

goto end;

2076

}

2752

2077

}

2753

2078

2754

2079

if(not debug){

2832

2157

2833

2158

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

2834

2159

if(mc.interfaces == NULL){

2835

struct dirent **direntries = NULL;

2160

struct dirent **direntries;

2836

2161

/* Look for any good interfaces */

2837

2162

ret = scandir(sys_class_net, &direntries, good_interface,

2838

2163

alphasort);

2842

2167

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

2843

2168

direntries[i]->d_name);

2844

2169

if(ret_errno != 0){

2845

errno = ret_errno;

2846

2170

perror_plus("argz_add");

2847

free(direntries[i]);

2848

2171

continue;

2849

2172

}

2850

2173

if(debug){

2851

2174

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

2852

2175

direntries[i]->d_name);

2853

2176

}

2854

free(direntries[i]);

2855

2177

}

2856

2178

free(direntries);

2857

2179

} else {

2858

if(ret == 0){

2859

free(direntries);

2860

}

2180

free(direntries);

2861

2181

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

2862

2182

exitcode = EXIT_FAILURE;

2863

2183

goto end;

2886

2206

break;

2887

2207

}

2888

2208

bool interface_was_up = interface_is_up(interface);

2889

errno = bring_up_interface(interface, delay);

2209

ret = bring_up_interface(interface, delay);

2890

2210

if(not interface_was_up){

2891

if(errno != 0){

2892

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

2893

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

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2894

2214

} else {

2895

errno = argz_add(&interfaces_to_take_down,

2896

&interfaces_to_take_down_size,

2897

interface);

2898

if(errno != 0){

2899

perror_plus("argz_add");

2900

}

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2901

2218

}

2902

2219

}

2903

2220

}

2919

2236

goto end;

2920

2237

}

2921

2238

2922

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

2239

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

2923

2240

if(ret == -1){

2924

2241

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

2925

2242

exitcode = EX_UNAVAILABLE;

2932

2249

goto end;

2933

2250

}

2934

2251

2935

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

2936

tempdir = mkdtemp(run_tempdir);

2937

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

2938

if(debug){

2939

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

2940

run_tempdir, old_tempdir);

2941

}

2942

tempdir = mkdtemp(old_tempdir);

2943

}

2944

if(tempdir == NULL){

2252

if(mkdtemp(tempdir) == NULL){

2945

2253

perror_plus("mkdtemp");

2946

2254

goto end;

2947

2255

}

2256

tempdir_created = true;

2948

2257

2949

2258

if(quit_now){

2950

2259

goto end;

3022

2331

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

3023

2332

(int)retry_interval);

3024

2333

}

3025

sleep((unsigned int)retry_interval);

2334

sleep((int)retry_interval);

3026

2335

}

3027

2336

3028

if(not quit_now){

2337

if (not quit_now){

3029

2338

exitcode = EXIT_SUCCESS;

3030

2339

}

3031

2340

3047

2356

3048

2357

/* Allocate a new server */

3049

2358

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3050

&config, NULL, NULL, &ret);

2359

&config, NULL, NULL, &ret_errno);

3051

2360

3052

2361

/* Free the Avahi configuration data */

3053

2362

avahi_server_config_free(&config);

3056

2365

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

3057

2366

if(mc.server == NULL){

3058

2367

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

3059

avahi_strerror(ret));

2368

avahi_strerror(ret_errno));

3060

2369

exitcode = EX_UNAVAILABLE;

3061

2370

goto end;

3062

2371

}

3086

2395

if(debug){

3087

2396

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

3088

2397

}

3089

2398

3090

2399

ret = avahi_loop_with_timeout(simple_poll,

3091

2400

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

3092

2401

if(debug){

3097

2406

end:

3098

2407

3099

2408

if(debug){

3100

if(signal_received){

3101

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

3102

argv[0], signal_received,

3103

strsignal(signal_received));

3104

} else {

3105

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

3106

}

2409

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

3107

2410

}

3108

2411

3109

2412

/* Cleanup things */

3120

2423

3121

2424

if(gnutls_initialized){

3122

2425

gnutls_certificate_free_credentials(mc.cred);

2426

gnutls_global_deinit();

3123

2427

gnutls_dh_params_deinit(mc.dh_params);

3124

2428

}

3125

2429

3133

2437

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

3134

2438

while(mc.current_server != NULL){

3135

2439

server *next = mc.current_server->next;

3136

#ifdef __GNUC__

3137

#pragma GCC diagnostic push

3138

#pragma GCC diagnostic ignored "-Wcast-qual"

3139

#endif

3140

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

3141

#ifdef __GNUC__

3142

#pragma GCC diagnostic pop

3143

#endif

3144

2440

free(mc.current_server);

3145

2441

mc.current_server = next;

3146

2442

}

3147

2443

}

3148

2444

3149

/* Re-raise privileges */

2445

/* Re-raise priviliges */

3150

2446

{

3151

ret = raise_privileges();

3152

if(ret != 0){

3153

errno = ret;

3154

perror_plus("Failed to raise privileges");

3155

} else {

3156

3157

/* Run network hooks */

3158

run_network_hooks("stop", interfaces_hooks != NULL ?

3159

interfaces_hooks : "", delay);

3160

3161

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

3162

{

3163

char *interface = NULL;

3164

while((interface = argz_next(interfaces_to_take_down,

3165

interfaces_to_take_down_size,

3166

interface))){

3167

ret = take_down_interface(interface);

3168

if(ret != 0){

3169

errno = ret;

3170

perror_plus("Failed to take down interface");

3171

}

3172

}

3173

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

3174

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

3175

" down\n");

3176

}

3177

}

3178

}

3179

3180

ret = lower_privileges_permanently();

3181

if(ret != 0){

3182

errno = ret;

3183

perror_plus("Failed to lower privileges permanently");

3184

}

2447

raise_privileges();

2448

2449

/* Run network hooks */

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2452

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

2463

}

2464

}

2465

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

2466

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

2467

" down\n");

2468

}

2469

}

2470

2471

lower_privileges_permanently();

3185

2472

}

3186

2473

3187

2474

free(interfaces_to_take_down);

3188

2475

free(interfaces_hooks);

3189

2476

3190

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

3191

uintmax_t level){

2477

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

2478

if(tempdir_created){

3192

2479

struct dirent **direntries = NULL;

3193

int dret;

3194

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

3195

O_RDONLY

3196

| O_NOFOLLOW

3197

| O_DIRECTORY

3198

| O_PATH));

3199

if(dir_fd == -1){

3200

perror_plus("open");

3201

return;

3202

}

3203

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

3204

notdotentries, alphasort);

3205

if(numentries >= 0){

2480

struct dirent *direntry = NULL;

2481

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

2482

alphasort);

2483

if (numentries > 0){

3206

2484

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

3207

if(debug){

3208

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

3209

dirname, direntries[i]->d_name);

3210

}

3211

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

3212

if(dret == -1){

3213

if(errno == EISDIR){

3214

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

3215

AT_REMOVEDIR);

3216

}

3217

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

3218

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

3219

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

3220

/* Recurse only in this special case */

3221

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

3222

dret = 0;

3223

}

3224

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

3225

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

3226

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

3227

}

3228

}

3229

free(direntries[i]);

3230

}

3231

3232

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

3233

free(direntries);

3234

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3235

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

3236

perror_plus("rmdir");

3237

}

3238

} else {

3239

perror_plus("scandirat");

3240

}

3241

close(dir_fd);

3242

}

3243

3244

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

3245

if(tempdir != NULL){

3246

clean_dir_at(-1, tempdir, 0);

2485

direntry = direntries[i];

2486

char *fullname = NULL;

2487

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

2488

direntry->d_name);

2489

if(ret < 0){

2490

perror_plus("asprintf");

2491

continue;

2492

}

2493

ret = remove(fullname);

2494

if(ret == -1){

2495

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

2496

strerror(errno));

2497

}

2498

free(fullname);

2499

}

2500

}

2501

2502

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

2503

free(direntries);

2504

if (numentries == -1){

2505

perror_plus("scandir");

2506

}

2507

ret = rmdir(tempdir);

2508

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

2509

perror_plus("rmdir");

2510

}

3247

2511

}

3248

2512

3249

2513

if(quit_now){