/mandos/release : revision 237.7.152

9

* "browse_callback", and parts of "main".

10

*

11

* Everything else is

12

13

14

*

15

* This file is part of Mandos.

16

*

17

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

18

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

19

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

20

* (at your option) any later version.

21

*

22

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

12

13

14

*

15

* This program is free software: you can redistribute it and/or

16

* modify it under the terms of the GNU General Public License as

17

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

18

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

19

*

20

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

23

21

* WITHOUT ANY WARRANTY; without even the implied warranty of

24

22

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

25

23

* General Public License for more details.

26

24

*

27

25

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

28

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

26

* along with this program. If not, see

27

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

29

28

*

30

29

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

31

30

*/

33

32

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

34

33

#ifndef _LARGEFILE_SOURCE

35

34

#define _LARGEFILE_SOURCE

36

#endif /* not _LARGEFILE_SOURCE */

35

#endif

37

36

#ifndef _FILE_OFFSET_BITS

38

37

#define _FILE_OFFSET_BITS 64

39

#endif /* not _FILE_OFFSET_BITS */

38

#endif

40

39

41

40

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

42

41

43

42

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

44

stdout, ferror() */

43

stdout, ferror(), remove() */

45

44

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

46

45

#include <stddef.h> /* NULL, size_t, ssize_t */

47

46

#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),

48

47

strtof(), abort() */

49

48

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

50

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

51

asprintf(), strncpy(), strsignal()

52

*/

49

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

50

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

53

51

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

54

52

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

55

53

sockaddr_in6, PF_INET6,

57

55

opendir(), DIR */

58

56

#include <sys/stat.h> /* open(), S_ISREG */

59

57

#include <sys/socket.h> /* socket(), struct sockaddr_in6,

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

58

inet_pton(), connect() */

59

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

63

60

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

64

61

*/

65

62

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

66

63

strtoimax() */

67

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

68

EAI_SYSTEM, ENETUNREACH,

69

EHOSTUNREACH, ECONNREFUSED, EPROTO,

70

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

71

ENOTEMPTY,

64

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

72

65

program_invocation_short_name */

73

66

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

74

67

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

79

72

*/

80

73

#include <unistd.h> /* close(), SEEK_SET, off_t, write(),

81

74

getuid(), getgid(), seteuid(),

82

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

83

unlinkat() */

84

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

75

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

76

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

85

77

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

86

78

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

87

79

argp_state, struct argp,

99

91

argz_delete(), argz_append(),

100

92

argz_stringify(), argz_add(),

101

93

argz_count() */

102

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

103

EAI_SYSTEM, gai_strerror() */

104

94

105

95

#ifdef __linux__

106

96

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

148

138

static const char sys_class_net[] = "/sys/class/net";

149

139

char *connect_to = NULL;

150

140

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

152

141

uid_t uid = 65534;

153

142

gid_t gid = 65534;

154

143

191

180

perror(print_text);

192

181

}

193

182

194

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

183

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

195

184

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

196

185

va_list ap;

197

186

va_start (ap, format);

198

187

199

188

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

200

189

program_invocation_short_name));

201

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

190

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

202

191

}

203

192

204

193

/*

206

195

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

207

196

* "buffer_length" is how much is already used.

208

197

*/

209

__attribute__((nonnull, warn_unused_result))

210

198

size_t incbuffer(char **buffer, size_t buffer_length,

211

199

size_t buffer_capacity){

212

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

213

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

214

if(new_buf == NULL){

215

int old_errno = errno;

216

free(*buffer);

217

errno = old_errno;

218

*buffer = NULL;

201

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

202

if(buffer == NULL){

219

203

return 0;

220

204

}

221

*buffer = new_buf;

222

205

buffer_capacity += BUFFER_SIZE;

223

206

}

224

207

return buffer_capacity;

225

208

}

226

209

227

210

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

228

__attribute__((nonnull, warn_unused_result))

229

211

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

230

212

int af, server **current_server){

231

213

int ret;

240

222

.af = af };

241

223

if(new_server->ip == NULL){

242

224

perror_plus("strdup");

243

free(new_server);

244

return false;

245

}

246

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

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

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

225

return false;

259

226

}

260

227

/* Special case of first server */

262

229

new_server->next = new_server;

263

230

new_server->prev = new_server;

264

231

*current_server = new_server;

232

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

265

233

} else {

266

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

267

234

new_server->next = *current_server;

268

235

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

269

236

new_server->prev->next = new_server;

270

237

(*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

255

/*

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

1200

659

return -1;

1201

660

}

1202

661

1203

/* If the interface is specified and we have a list of interfaces */

1204

662

if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){

1205

663

/* Check if the interface is one of the interfaces we are using */

1206

664

bool match = false;

1207

665

{

1208

666

char *interface = NULL;

1209

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

1210

mc->interfaces_size,

1211

interface))){

667

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

668

interface))){

1212

669

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

1213

670

match = true;

1214

671

break;

1216

673

}

1217

674

}

1218

675

if(not match){

1219

/* This interface does not match any in the list, so we don't

1220

connect to the server */

1221

676

if(debug){

1222

677

char interface[IF_NAMESIZE];

1223

678

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

1243

698

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

1244

699

}

1245

700

1246

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

701

tcp_sd = socket(pf, SOCK_STREAM, 0);

1247

702

if(tcp_sd < 0){

1248

703

int e = errno;

1249

704

perror_plus("socket");

1256

711

goto mandos_end;

1257

712

}

1258

713

714

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

1259

715

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);

716

to.in6.sin6_family = (sa_family_t)af;

717

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

1263

718

} 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);

719

to.in.sin_family = (sa_family_t)af;

720

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

1267

721

}

1268

722

if(ret < 0 ){

1269

723

int e = errno;

1278

732

goto mandos_end;

1279

733

}

1280

734

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)){

735

to.in6.sin6_port = htons(port);

736

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

737

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

738

-Wunreachable-code*/

1284

739

if(if_index == AVAHI_IF_UNSPEC){

1285

740

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

1286

741

" incomplete without a network interface\n");

1288

743

goto mandos_end;

1289

744

}

1290

745

/* Set the network interface number as scope */

1291

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

746

to.in6.sin6_scope_id = (uint32_t)if_index;

1292

747

}

1293

748

} else {

1294

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

749

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

750

-Wconversion and

751

-Wunreachable-code */

1295

752

}

1296

753

1297

754

if(quit_now){

1314

771

}

1315

772

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1316

773

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;

774

const char *pcret;

775

if(af == AF_INET6){

776

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

777

sizeof(addrstr));

778

} else {

779

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

780

sizeof(addrstr));

781

}

782

if(pcret == NULL){

783

perror_plus("inet_ntop");

784

} else {

785

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

786

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

787

}

788

}

789

}

790

791

if(quit_now){

792

errno = EINTR;

793

goto mandos_end;

794

}

795

796

if(af == AF_INET6){

797

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

798

} else {

799

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

800

}

801

if(ret < 0){

802

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

803

int e = errno;

804

perror_plus("connect");

805

errno = e;

806

}

807

goto mandos_end;

808

}

809

810

if(quit_now){

811

errno = EINTR;

812

goto mandos_end;

1397

813

}

1398

814

1399

815

const char *out = mandos_protocol_version;

1553

969

&decrypted_buffer, mc);

1554

970

if(decrypted_buffer_size >= 0){

1555

971

1556

clearerr(stdout);

1557

972

written = 0;

1558

973

while(written < (size_t) decrypted_buffer_size){

1559

974

if(quit_now){

1575

990

}

1576

991

written += (size_t)ret;

1577

992

}

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

993

retval = 0;

1589

994

}

1590

995

}

1593

998

1594

999

mandos_end:

1595

1000

{

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

1001

int e = errno;

1603

1002

free(decrypted_buffer);

1604

1003

free(buffer);

1605

1004

if(tcp_sd >= 0){

1606

ret = close(tcp_sd);

1005

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

1607

1006

}

1608

1007

if(ret == -1){

1609

1008

if(e == 0){

1634

1033

AVAHI_GCC_UNUSED AvahiStringList *txt,

1635

1034

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1636

1035

flags,

1637

void *mc){

1036

void* mc){

1638

1037

if(r == NULL){

1639

1038

return;

1640

1039

}

1643

1042

timed out */

1644

1043

1645

1044

if(quit_now){

1646

avahi_s_service_resolver_free(r);

1647

1045

return;

1648

1046

}

1649

1047

1694

1092

const char *domain,

1695

1093

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1696

1094

flags,

1697

void *mc){

1095

void* mc){

1698

1096

if(b == NULL){

1699

1097

return;

1700

1098

}

1760

1158

errno = old_errno;

1761

1159

}

1762

1160

1763

__attribute__((nonnull, warn_unused_result))

1764

1161

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

1765

1162

int ret;

1766

int old_errno;

1163

error_t ret_errno;

1767

1164

1768

1165

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

1769

1166

if(s < 0){

1770

old_errno = errno;

1167

ret_errno = errno;

1771

1168

perror_plus("socket");

1772

errno = old_errno;

1169

errno = ret_errno;

1773

1170

return false;

1774

1171

}

1775

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

1776

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

1172

strcpy(ifr->ifr_name, ifname);

1777

1173

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1778

1174

if(ret == -1){

1779

1175

if(debug){

1780

old_errno = errno;

1176

ret_errno = errno;

1781

1177

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;

1178

errno = ret_errno;

1788

1179

}

1789

1180

return false;

1790

1181

}

1791

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

1792

old_errno = errno;

1793

perror_plus("close");

1794

errno = old_errno;

1795

}

1796

1182

return true;

1797

1183

}

1798

1184

1799

__attribute__((nonnull, warn_unused_result))

1800

1185

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

1801

1186

1802

1187

/* Reject the loopback device */

1844

1229

* corresponds to an acceptable network device.

1845

1230

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

1846

1231

*/

1847

__attribute__((nonnull, warn_unused_result))

1848

1232

int good_interface(const struct dirent *if_entry){

1849

1233

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

1850

1234

return 0;

1868

1252

/*

1869

1253

* This function determines if a network interface is up.

1870

1254

*/

1871

__attribute__((nonnull, warn_unused_result))

1872

1255

bool interface_is_up(const char *interface){

1873

1256

struct ifreq ifr;

1874

1257

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

1885

1268

/*

1886

1269

* This function determines if a network interface is running

1887

1270

*/

1888

__attribute__((nonnull, warn_unused_result))

1889

1271

bool interface_is_running(const char *interface){

1890

1272

struct ifreq ifr;

1891

1273

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

1899

1281

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

1900

1282

}

1901

1283

1902

__attribute__((nonnull, pure, warn_unused_result))

1903

1284

int notdotentries(const struct dirent *direntry){

1904

1285

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

1905

1286

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

1912

1293

}

1913

1294

1914

1295

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

1915

__attribute__((nonnull, warn_unused_result))

1916

1296

int runnable_hook(const struct dirent *direntry){

1917

1297

int ret;

1918

1298

size_t sret;

1926

1306

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

1927

1307

"abcdefghijklmnopqrstuvwxyz"

1928

1308

"0123456789"

1929

"_.-");

1309

"_-");

1930

1310

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

1931

1311

/* Contains non-allowed characters */

1932

1312

if(debug){

1936

1316

return 0;

1937

1317

}

1938

1318

1939

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

1319

char *fullname = NULL;

1320

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

1321

if(ret < 0){

1322

perror_plus("asprintf");

1323

return 0;

1324

}

1325

1326

ret = stat(fullname, &st);

1940

1327

if(ret == -1){

1941

1328

if(debug){

1942

1329

perror_plus("Could not stat hook");

1966

1353

return 1;

1967

1354

}

1968

1355

1969

__attribute__((nonnull, warn_unused_result))

1970

1356

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1971

1357

mandos_context *mc){

1972

1358

int ret;

1976

1362

1977

1363

while(true){

1978

1364

if(mc->current_server == NULL){

1979

if(debug){

1365

if (debug){

1980

1366

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

1981

1367

" No timeout!\n");

1982

1368

}

1983

1369

ret = avahi_simple_poll_iterate(s, -1);

1984

1370

} else {

1985

if(debug){

1371

if (debug){

1986

1372

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

1987

1373

" it, or wait\n");

1988

1374

}

2005

1391

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

2006

1392

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

2007

1393

2008

if(debug){

1394

if (debug){

2009

1395

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

2010

1396

block_time);

2011

1397

}

2033

1419

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

2034

1420

}

2035

1421

if(ret != 0){

2036

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

1422

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

2037

1423

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

2038

1424

}

2039

1425

}

2040

1426

}

2041

1427

}

2042

1428

2043

__attribute__((nonnull))

2044

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

1429

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

1430

error_t raise_privileges(void){

1431

error_t old_errno = errno;

1432

error_t ret_errno = 0;

1433

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

1434

ret_errno = errno;

1435

perror_plus("seteuid");

1436

}

1437

errno = old_errno;

1438

return ret_errno;

1439

}

1440

1441

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

1442

error_t raise_privileges_permanently(void){

1443

error_t old_errno = errno;

1444

error_t ret_errno = raise_privileges();

1445

if(ret_errno != 0){

1446

errno = old_errno;

1447

return ret_errno;

1448

}

1449

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

1450

ret_errno = errno;

1451

perror_plus("seteuid");

1452

}

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

1457

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

1458

error_t lower_privileges(void){

1459

error_t old_errno = errno;

1460

error_t ret_errno = 0;

1461

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

1462

ret_errno = errno;

1463

perror_plus("seteuid");

1464

}

1465

errno = old_errno;

1466

return ret_errno;

1467

}

1468

1469

/* Lower privileges permanently */

1470

error_t lower_privileges_permanently(void){

1471

error_t old_errno = errno;

1472

error_t ret_errno = 0;

1473

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

1474

ret_errno = errno;

1475

perror_plus("setuid");

1476

}

1477

errno = old_errno;

1478

return ret_errno;

1479

}

1480

1481

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

2045

1482

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);

1483

struct dirent **direntries;

1484

struct dirent *direntry;

1485

int ret;

1486

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

1487

alphasort);

2069

1488

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);

1489

if(errno == ENOENT){

1490

if(debug){

1491

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

1492

" found\n", hookdir);

1493

}

1494

} else {

1495

perror_plus("scandir");

2081

1496

}

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){

1497

} else {

1498

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

1499

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

1500

direntry = direntries[i];

1501

char *fullname = NULL;

1502

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

1503

if(ret < 0){

2128

1504

perror_plus("asprintf");

2129

_exit(EX_OSERR);

2130

}

2131

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

2132

if(ret == -1){

1505

continue;

1506

}

1507

if(debug){

1508

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

1509

direntry->d_name);

1510

}

1511

pid_t hook_pid = fork();

1512

if(hook_pid == 0){

1513

/* Child */

1514

/* Raise privileges */

1515

raise_privileges_permanently();

1516

/* Set group */

1517

errno = 0;

1518

ret = setgid(0);

1519

if(ret == -1){

1520

perror_plus("setgid");

1521

}

1522

/* Reset supplementary groups */

1523

errno = 0;

1524

ret = setgroups(0, NULL);

1525

if(ret == -1){

1526

perror_plus("setgroups");

1527

}

1528

dup2(devnull, STDIN_FILENO);

1529

close(devnull);

1530

dup2(STDERR_FILENO, STDOUT_FILENO);

1531

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

1532

if(ret == -1){

1533

perror_plus("setenv");

1534

_exit(EX_OSERR);

1535

}

1536

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

1537

if(ret == -1){

1538

perror_plus("setenv");

1539

_exit(EX_OSERR);

1540

}

1541

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

1542

if(ret == -1){

1543

perror_plus("setenv");

1544

_exit(EX_OSERR);

1545

}

1546

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

1547

if(ret == -1){

1548

perror_plus("setenv");

1549

_exit(EX_OSERR);

1550

}

1551

char *delaystring;

1552

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

1553

if(ret == -1){

1554

perror_plus("asprintf");

1555

_exit(EX_OSERR);

1556

}

1557

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

1558

if(ret == -1){

1559

free(delaystring);

1560

perror_plus("setenv");

1561

_exit(EX_OSERR);

1562

}

2133

1563

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;

1564

if(connect_to != NULL){

1565

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

1566

if(ret == -1){

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1570

}

1571

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

1572

perror_plus("execl");

1573

_exit(EXIT_FAILURE);

1574

}

2202

1575

} 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);

1576

int status;

1577

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

1578

perror_plus("waitpid");

1579

free(fullname);

1580

continue;

1581

}

1582

if(WIFEXITED(status)){

1583

if(WEXITSTATUS(status) != 0){

1584

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

1585

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

1586

WEXITSTATUS(status));

1587

free(fullname);

1588

continue;

1589

}

1590

} else if(WIFSIGNALED(status)){

1591

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

1592

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

1593

WTERMSIG(status));

1594

free(fullname);

1595

continue;

1596

} else {

1597

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

1598

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

1599

free(fullname);

1600

continue;

1601

}

1602

}

1603

free(fullname);

1604

if(debug){

1605

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

1606

direntry->d_name);

1607

}

1608

}

1609

close(devnull);

1610

}

1611

return true;

2222

1612

}

2223

1613

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;

1614

error_t bring_up_interface(const char *const interface,

1615

const float delay){

1616

int sd = -1;

1617

error_t old_errno = errno;

1618

error_t ret_errno = 0;

1619

int ret, ret_setflags;

2229

1620

struct ifreq network;

2230

1621

unsigned int if_index = if_nametoindex(interface);

2231

1622

if(if_index == 0){

2240

1631

}

2241

1632

2242

1633

if(not interface_is_up(interface)){

2243

int ret_errno = 0;

2244

int ioctl_errno = 0;

2245

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

1634

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

2246

1635

ret_errno = errno;

2247

1636

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

2248

1637

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

2249

errno = old_errno;

2250

1638

return ret_errno;

2251

1639

}

2252

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

1640

network.ifr_flags |= IFF_UP;

2253

1641

2254

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

2255

if(sd == -1){

1642

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1643

if(sd < 0){

2256

1644

ret_errno = errno;

2257

1645

perror_plus("socket");

2258

1646

errno = old_errno;

2259

1647

return ret_errno;

2260

1648

}

2261

1649

2262

1650

if(quit_now){

2263

ret = close(sd);

2264

if(ret == -1){

2265

perror_plus("close");

2266

}

1651

close(sd);

2267

1652

errno = old_errno;

2268

1653

return EINTR;

2269

1654

}

2273

1658

interface);

2274

1659

}

2275

1660

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

}

1661

/* Raise priviliges */

1662

raise_privileges();

2282

1663

2283

1664

#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

}

1665

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1666

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

1667

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

1668

bool restore_loglevel = true;

1669

if(ret_linux == -1){

1670

restore_loglevel = false;

1671

perror_plus("klogctl");

2295

1672

}

2296

1673

#endif /* __linux__ */

2297

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

2298

ioctl_errno = errno;

1674

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

1675

ret_errno = errno;

2299

1676

#ifdef __linux__

2300

1677

if(restore_loglevel){

2301

1678

ret_linux = klogctl(7, NULL, 0);

2305

1682

}

2306

1683

#endif /* __linux__ */

2307

1684

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

}

1685

/* Lower privileges */

1686

lower_privileges();

2317

1687

2318

1688

/* Close the socket */

2319

ret = close(sd);

1689

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

2320

1690

if(ret == -1){

2321

1691

perror_plus("close");

2322

1692

}

2323

1693

2324

1694

if(ret_setflags == -1){

2325

errno = ioctl_errno;

1695

errno = ret_errno;

2326

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2327

1697

errno = old_errno;

2328

return ioctl_errno;

1698

return ret_errno;

2329

1699

}

2330

1700

} else if(debug){

2331

1701

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

2334

1704

2335

1705

/* Sleep checking until interface is running.

2336

1706

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

2337

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

1707

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

2338

1708

if(interface_is_running(interface)){

2339

1709

break;

2340

1710

}

2349

1719

return 0;

2350

1720

}

2351

1721

2352

__attribute__((nonnull, warn_unused_result))

2353

int take_down_interface(const char *const interface){

2354

int old_errno = errno;

1722

error_t take_down_interface(const char *const interface){

1723

int sd = -1;

1724

error_t old_errno = errno;

1725

error_t ret_errno = 0;

1726

int ret, ret_setflags;

2355

1727

struct ifreq network;

2356

1728

unsigned int if_index = if_nametoindex(interface);

2357

1729

if(if_index == 0){

2360

1732

return ENXIO;

2361

1733

}

2362

1734

if(interface_is_up(interface)){

2363

int ret_errno = 0;

2364

int ioctl_errno = 0;

2365

1735

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

2366

1736

ret_errno = errno;

2367

1737

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

2368

1738

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

2369

errno = old_errno;

2370

1739

return ret_errno;

2371

1740

}

2372

1741

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

2373

1742

2374

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

2375

if(sd == -1){

1743

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1744

if(sd < 0){

2376

1745

ret_errno = errno;

2377

1746

perror_plus("socket");

2378

1747

errno = old_errno;

2384

1753

interface);

2385

1754

}

2386

1755

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

}

1756

/* Raise priviliges */

1757

raise_privileges();

1758

1759

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

1760

ret_errno = errno;

1761

1762

/* Lower privileges */

1763

lower_privileges();

2406

1764

2407

1765

/* Close the socket */

2408

int ret = close(sd);

1766

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

2409

1767

if(ret == -1){

2410

1768

perror_plus("close");

2411

1769

}

2412

1770

2413

1771

if(ret_setflags == -1){

2414

errno = ioctl_errno;

1772

errno = ret_errno;

2415

1773

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2416

1774

errno = old_errno;

2417

return ioctl_errno;

1775

return ret_errno;

2418

1776

}

2419

1777

} else if(debug){

2420

1778

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

2426

1784

}

2427

1785

2428

1786

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 };

1787

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

1788

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

1789

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

1790

.interfaces = NULL, .interfaces_size = 0 };

2434

1791

AvahiSServiceBrowser *sb = NULL;

2435

1792

error_t ret_errno;

2436

1793

int ret;

2439

1796

int exitcode = EXIT_SUCCESS;

2440

1797

char *interfaces_to_take_down = NULL;

2441

1798

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;

1799

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

1800

bool tempdir_created = false;

2445

1801

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2446

1802

const char *seckey = PATHDIR "/" SECKEY;

2447

1803

const char *pubkey = PATHDIR "/" PUBKEY;

2448

const char *dh_params_file = NULL;

2449

1804

char *interfaces_hooks = NULL;

1805

size_t interfaces_hooks_size = 0;

2450

1806

2451

1807

bool gnutls_initialized = false;

2452

1808

bool gpgme_initialized = false;

2504

1860

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

2505

1861

" Diffie-Hellman key exchange",

2506

1862

.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

1863

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

2513

1864

.arg = "STRING",

2514

1865

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

2569

1920

}

2570

1921

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

2571

1922

break;

2572

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

2573

dh_params_file = arg;

2574

break;

2575

1923

case 130: /* --priority */

2576

1924

mc.priority = arg;

2577

1925

break;

2617

1965

.args_doc = "",

2618

1966

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

2619

1967

" 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){

1968

ret = argp_parse(&argp, argc, argv,

1969

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1970

switch(ret){

2623

1971

case 0:

2624

1972

break;

2625

1973

case ENOMEM:

2626

1974

default:

2627

errno = ret_errno;

1975

errno = ret;

2628

1976

perror_plus("argp_parse");

2629

1977

exitcode = EX_OSERR;

2630

1978

goto end;

2633

1981

goto end;

2634

1982

}

2635

1983

}

2636

1984

2637

1985

{

2638

1986

/* Work around Debian bug #633582:

2639

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

1987

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

2640

1988

2641

/* Re-raise privileges */

2642

ret = raise_privileges();

2643

if(ret != 0){

2644

errno = ret;

2645

perror_plus("Failed to raise privileges");

2646

} else {

1989

/* Re-raise priviliges */

1990

if(raise_privileges() == 0){

2647

1991

struct stat st;

2648

1992

2649

1993

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

2663

2007

}

2664

2008

}

2665

2009

}

2666

close(seckey_fd);

2010

TEMP_FAILURE_RETRY(close(seckey_fd));

2667

2011

}

2668

2012

}

2669

2013

2670

2014

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

2671

2015

int pubkey_fd = open(pubkey, O_RDONLY);

2672

2016

if(pubkey_fd == -1){

2684

2028

}

2685

2029

}

2686

2030

}

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

2031

TEMP_FAILURE_RETRY(close(pubkey_fd));

2032

}

2033

}

2034

2713

2035

/* Lower privileges */

2714

ret = lower_privileges();

2715

if(ret != 0){

2716

errno = ret;

2717

perror_plus("Failed to lower privileges");

2718

}

2036

lower_privileges();

2719

2037

}

2720

2038

}

2721

2039

2745

2063

goto end;

2746

2064

}

2747

2065

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);

2066

interfaces_hooks_size = mc.interfaces_size;

2067

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2068

(int)',');

2069

}

2070

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

2071

interfaces_hooks : "", delay)){

2072

goto end;

2073

}

2752

2074

}

2753

2075

2754

2076

if(not debug){

2832

2154

2833

2155

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

2834

2156

if(mc.interfaces == NULL){

2835

struct dirent **direntries = NULL;

2157

struct dirent **direntries;

2836

2158

/* Look for any good interfaces */

2837

2159

ret = scandir(sys_class_net, &direntries, good_interface,

2838

2160

alphasort);

2842

2164

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

2843

2165

direntries[i]->d_name);

2844

2166

if(ret_errno != 0){

2845

errno = ret_errno;

2846

2167

perror_plus("argz_add");

2847

free(direntries[i]);

2848

2168

continue;

2849

2169

}

2850

2170

if(debug){

2851

2171

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

2852

2172

direntries[i]->d_name);

2853

2173

}

2854

free(direntries[i]);

2855

2174

}

2856

2175

free(direntries);

2857

2176

} else {

2858

if(ret == 0){

2859

free(direntries);

2860

}

2177

free(direntries);

2861

2178

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

2862

2179

exitcode = EXIT_FAILURE;

2863

2180

goto end;

2864

2181

}

2865

2182

}

2866

2183

2867

/* Bring up interfaces which are down, and remove any "none"s */

2184

/* Bring up interfaces which are down */

2868

2185

{

2869

2186

char *interface = NULL;

2870

2187

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2886

2203

break;

2887

2204

}

2888

2205

bool interface_was_up = interface_is_up(interface);

2889

errno = bring_up_interface(interface, delay);

2206

ret = bring_up_interface(interface, delay);

2890

2207

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));

2208

if(ret != 0){

2209

errno = ret;

2210

perror_plus("Failed to bring up interface");

2894

2211

} 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

}

2212

ret_errno = argz_add(&interfaces_to_take_down,

2213

&interfaces_to_take_down_size,

2214

interface);

2901

2215

}

2902

2216

}

2903

2217

}

2919

2233

goto end;

2920

2234

}

2921

2235

2922

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

2236

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

2923

2237

if(ret == -1){

2924

2238

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

2925

2239

exitcode = EX_UNAVAILABLE;

2932

2246

goto end;

2933

2247

}

2934

2248

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){

2249

if(mkdtemp(tempdir) == NULL){

2945

2250

perror_plus("mkdtemp");

2946

2251

goto end;

2947

2252

}

2253

tempdir_created = true;

2948

2254

2949

2255

if(quit_now){

2950

2256

goto end;

3022

2328

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

3023

2329

(int)retry_interval);

3024

2330

}

3025

sleep((unsigned int)retry_interval);

2331

sleep((int)retry_interval);

3026

2332

}

3027

2333

3028

if(not quit_now){

2334

if (not quit_now){

3029

2335

exitcode = EXIT_SUCCESS;

3030

2336

}

3031

2337

3047

2353

3048

2354

/* Allocate a new server */

3049

2355

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3050

&config, NULL, NULL, &ret);

2356

&config, NULL, NULL, &ret_errno);

3051

2357

3052

2358

/* Free the Avahi configuration data */

3053

2359

avahi_server_config_free(&config);

3056

2362

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

3057

2363

if(mc.server == NULL){

3058

2364

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

3059

avahi_strerror(ret));

2365

avahi_strerror(ret_errno));

3060

2366

exitcode = EX_UNAVAILABLE;

3061

2367

goto end;

3062

2368

}

3086

2392

if(debug){

3087

2393

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

3088

2394

}

3089

2395

3090

2396

ret = avahi_loop_with_timeout(simple_poll,

3091

2397

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

3092

2398

if(debug){

3097

2403

end:

3098

2404

3099

2405

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

}

2406

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

3107

2407

}

3108

2408

3109

2409

/* Cleanup things */

3120

2420

3121

2421

if(gnutls_initialized){

3122

2422

gnutls_certificate_free_credentials(mc.cred);

2423

gnutls_global_deinit();

3123

2424

gnutls_dh_params_deinit(mc.dh_params);

3124

2425

}

3125

2426

3133

2434

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

3134

2435

while(mc.current_server != NULL){

3135

2436

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

2437

free(mc.current_server);

3145

2438

mc.current_server = next;

3146

2439

}

3147

2440

}

3148

2441

3149

/* Re-raise privileges */

2442

/* Re-raise priviliges */

3150

2443

{

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

}

2444

raise_privileges();

2445

2446

/* Run network hooks */

2447

run_network_hooks("stop", interfaces_hooks != NULL ?

2448

interfaces_hooks : "", delay);

2449

2450

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

2451

{

2452

char *interface = NULL;

2453

while((interface=argz_next(interfaces_to_take_down,

2454

interfaces_to_take_down_size,

2455

interface))){

2456

ret_errno = take_down_interface(interface);

2457

if(ret_errno != 0){

2458

errno = ret_errno;

2459

perror_plus("Failed to take down interface");

2460

}

2461

}

2462

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

2463

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

2464

" down\n");

2465

}

2466

}

2467

2468

lower_privileges_permanently();

3185

2469

}

3186

2470

3187

2471

free(interfaces_to_take_down);

3188

2472

free(interfaces_hooks);

3189

2473

3190

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

3191

uintmax_t level){

2474

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

2475

if(tempdir_created){

3192

2476

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){

2477

struct dirent *direntry = NULL;

2478

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

2479

alphasort);

2480

if (numentries > 0){

3206

2481

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);

2482

direntry = direntries[i];

2483

char *fullname = NULL;

2484

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

2485

direntry->d_name);

2486

if(ret < 0){

2487

perror_plus("asprintf");

2488

continue;

2489

}

2490

ret = remove(fullname);

2491

if(ret == -1){

2492

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

2493

strerror(errno));

2494

}

2495

free(fullname);

2496

}

2497

}

2498

2499

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

2500

free(direntries);

2501

if (numentries == -1){

2502

perror_plus("scandir");

2503

}

2504

ret = rmdir(tempdir);

2505

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

2506

perror_plus("rmdir");

2507

}

3247

2508

}

3248

2509

3249

2510

if(quit_now){