/mandos/release : revision 237.7.166

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

247

/*

276

248

* Initialize GPGME.

277

249

*/

278

__attribute__((nonnull, warn_unused_result))

279

static bool init_gpgme(const char * const seckey,

280

const char * const pubkey,

281

const char * const tempdir,

282

mandos_context *mc){

250

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

251

const char *tempdir, mandos_context *mc){

283

252

gpgme_error_t rc;

284

253

gpgme_engine_info_t engine_info;

285

254

286

255

/*

287

256

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

288

257

*/

289

bool import_key(const char * const filename){

258

bool import_key(const char *filename){

290

259

int ret;

291

260

int fd;

292

261

gpgme_data_t pgp_data;

310

279

gpgme_strsource(rc), gpgme_strerror(rc));

311

280

return false;

312

281

}

313

{

314

gpgme_import_result_t import_result

315

= gpgme_op_import_result(mc->ctx);

316

if((import_result->imported < 1

317

or import_result->not_imported > 0)

318

and import_result->unchanged == 0){

319

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

320

fprintf_plus(stderr,

321

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

322

import_result->considered);

323

fprintf_plus(stderr,

324

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

325

import_result->no_user_id);

326

fprintf_plus(stderr,

327

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

328

import_result->imported);

329

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

330

import_result->imported_rsa);

331

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

332

import_result->unchanged);

333

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

334

import_result->new_user_ids);

335

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

336

import_result->new_sub_keys);

337

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

338

import_result->new_signatures);

339

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

340

import_result->new_revocations);

341

fprintf_plus(stderr,

342

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

343

import_result->secret_read);

344

fprintf_plus(stderr,

345

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

346

import_result->secret_imported);

347

fprintf_plus(stderr,

348

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

349

import_result->secret_unchanged);

350

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

351

import_result->not_imported);

352

for(gpgme_import_status_t import_status

353

= import_result->imports;

354

import_status != NULL;

355

import_status = import_status->next){

356

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

357

import_status->fpr);

358

if(import_status->result != GPG_ERR_NO_ERROR){

359

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

360

gpgme_strsource(import_status->result),

361

gpgme_strerror(import_status->result));

362

}

363

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

364

fprintf_plus(stderr,

365

import_status->status & GPGME_IMPORT_NEW

366

? "The key was new.\n"

367

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

368

fprintf_plus(stderr,

369

import_status->status & GPGME_IMPORT_UID

370

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

371

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

372

fprintf_plus(stderr,

373

import_status->status & GPGME_IMPORT_SIG

374

? "The key contained new signatures.\n"

375

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

376

fprintf_plus(stderr,

377

import_status->status & GPGME_IMPORT_SUBKEY

378

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

379

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

380

fprintf_plus(stderr,

381

import_status->status & GPGME_IMPORT_SECRET

382

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

383

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

384

}

385

return false;

386

}

387

}

388

282

389

ret = close(fd);

283

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

390

284

if(ret == -1){

391

285

perror_plus("close");

392

286

}

431

325

/* Create new GPGME "context" */

432

326

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

433

327

if(rc != GPG_ERR_NO_ERROR){

434

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

435

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));

436

331

return false;

437

332

}

438

333

447

342

* Decrypt OpenPGP data.

448

343

* Returns -1 on error

449

344

*/

450

__attribute__((nonnull, warn_unused_result))

451

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

452

346

size_t crypto_size,

453

347

char **plaintext,

474

368

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

475

369

rc = gpgme_data_new(&dh_plain);

476

370

if(rc != GPG_ERR_NO_ERROR){

477

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",

478

373

gpgme_strsource(rc), gpgme_strerror(rc));

479

374

gpgme_data_release(dh_crypto);

480

375

return -1;

493

388

if(result == NULL){

494

389

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

495

390

} else {

496

if(result->unsupported_algorithm != NULL) {

497

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

498

result->unsupported_algorithm);

499

}

500

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

501

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);

502

395

if(result->file_name != NULL){

503

396

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

504

397

}

505

506

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

507

r = r->next){

398

gpgme_recipient_t recipient;

399

recipient = result->recipients;

400

while(recipient != NULL){

508

401

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

509

gpgme_pubkey_algo_name(r->pubkey_algo));

510

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);

511

405

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

512

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

408

recipient = recipient->next;

513

409

}

514

410

}

515

411

}

571

467

return plaintext_length;

572

468

}

573

469

574

__attribute__((warn_unused_result, const))

575

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

576

if(str == NULL)

577

return "(unknown)";

578

return str;

579

}

580

581

__attribute__((warn_unused_result))

582

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

583

471

const char *ret = gnutls_strerror(value);

584

return safe_string(ret);

472

if(ret == NULL)

473

ret = "(unknown)";

474

return ret;

585

475

}

586

476

587

477

/* GnuTLS log function callback */

588

__attribute__((nonnull))

589

478

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

590

479

const char* string){

591

480

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

592

481

}

593

482

594

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

595

483

static int init_gnutls_global(const char *pubkeyfilename,

596

484

const char *seckeyfilename,

597

const char *dhparamsfilename,

598

485

mandos_context *mc){

599

486

int ret;

600

unsigned int uret;

601

487

602

488

if(debug){

603

489

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

604

490

}

605

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

606

499

if(debug){

607

500

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

608

501

* - GnuTLS manual

616

509

if(ret != GNUTLS_E_SUCCESS){

617

510

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

618

511

safer_gnutls_strerror(ret));

512

gnutls_global_deinit();

619

513

return -1;

620

514

}

621

515

646

540

safer_gnutls_strerror(ret));

647

541

goto globalfail;

648

542

}

649

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

650

if(dhparamsfilename != NULL){

651

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

652

do {

653

int dhpfile = open(dhparamsfilename, O_RDONLY);

654

if(dhpfile == -1){

655

perror_plus("open");

656

dhparamsfilename = NULL;

657

break;

658

}

659

size_t params_capacity = 0;

660

while(true){

661

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

662

(size_t)params.size,

663

(size_t)params_capacity);

664

if(params_capacity == 0){

665

perror_plus("incbuffer");

666

free(params.data);

667

params.data = NULL;

668

dhparamsfilename = NULL;

669

break;

670

}

671

ssize_t bytes_read = read(dhpfile,

672

params.data + params.size,

673

BUFFER_SIZE);

674

/* EOF */

675

if(bytes_read == 0){

676

break;

677

}

678

/* check bytes_read for failure */

679

if(bytes_read < 0){

680

perror_plus("read");

681

free(params.data);

682

params.data = NULL;

683

dhparamsfilename = NULL;

684

break;

685

}

686

params.size += (unsigned int)bytes_read;

687

}

688

ret = close(dhpfile);

689

if(ret == -1){

690

perror_plus("close");

691

}

692

if(params.data == NULL){

693

dhparamsfilename = NULL;

694

}

695

if(dhparamsfilename == NULL){

696

break;

697

}

698

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

699

GNUTLS_X509_FMT_PEM);

700

if(ret != GNUTLS_E_SUCCESS){

701

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

702

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

703

safer_gnutls_strerror(ret));

704

dhparamsfilename = NULL;

705

}

706

free(params.data);

707

} while(false);

708

}

709

if(dhparamsfilename == NULL){

710

if(mc->dh_bits == 0){

711

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

712

/* Try to read the private key file */

713

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

714

do {

715

int secfile = open(seckeyfilename, O_RDONLY);

716

if(secfile == -1){

717

perror_plus("open");

718

break;

719

}

720

size_t buffer_capacity = 0;

721

while(true){

722

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

723

(size_t)buffer.size,

724

(size_t)buffer_capacity);

725

if(buffer_capacity == 0){

726

perror_plus("incbuffer");

727

free(buffer.data);

728

buffer.data = NULL;

729

break;

730

}

731

ssize_t bytes_read = read(secfile,

732

buffer.data + buffer.size,

733

BUFFER_SIZE);

734

/* EOF */

735

if(bytes_read == 0){

736

break;

737

}

738

/* check bytes_read for failure */

739

if(bytes_read < 0){

740

perror_plus("read");

741

free(buffer.data);

742

buffer.data = NULL;

743

break;

744

}

745

buffer.size += (unsigned int)bytes_read;

746

}

747

close(secfile);

748

} while(false);

749

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

750

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

751

if(buffer.data != NULL){

752

{

753

gnutls_openpgp_privkey_t privkey = NULL;

754

ret = gnutls_openpgp_privkey_init(&privkey);

755

if(ret != GNUTLS_E_SUCCESS){

756

fprintf_plus(stderr, "Error initializing OpenPGP key"

757

" structure: %s",

758

safer_gnutls_strerror(ret));

759

free(buffer.data);

760

buffer.data = NULL;

761

} else {

762

ret = gnutls_openpgp_privkey_import

763

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

764

if(ret != GNUTLS_E_SUCCESS){

765

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

766

safer_gnutls_strerror(ret));

767

privkey = NULL;

768

}

769

free(buffer.data);

770

buffer.data = NULL;

771

if(privkey != NULL){

772

/* Use private key to suggest an appropriate

773

sec_param */

774

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

775

gnutls_openpgp_privkey_deinit(privkey);

776

if(debug){

777

fprintf_plus(stderr, "This OpenPGP key implies using"

778

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

779

safe_string(gnutls_sec_param_get_name

780

(sec_param)));

781

}

782

}

783

}

784

}

785

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

786

/* Err on the side of caution */

787

sec_param = GNUTLS_SEC_PARAM_ULTRA;

788

if(debug){

789

fprintf_plus(stderr, "Falling back to security parameter"

790

" \"%s\"\n",

791

safe_string(gnutls_sec_param_get_name

792

(sec_param)));

793

}

794

}

795

}

796

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

797

if(uret != 0){

798

mc->dh_bits = uret;

799

if(debug){

800

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

801

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

802

safe_string(gnutls_sec_param_get_name

803

(sec_param)),

804

mc->dh_bits);

805

}

806

} else {

807

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

808

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

809

safe_string(gnutls_sec_param_get_name

810

(sec_param)),

811

safer_gnutls_strerror(ret));

812

goto globalfail;

813

}

814

} else if(debug){

815

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

816

mc->dh_bits);

817

}

818

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

819

if(ret != GNUTLS_E_SUCCESS){

820

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

821

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

822

safer_gnutls_strerror(ret));

823

goto globalfail;

824

}

825

}

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

826

550

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

827

551

828

552

return 0;

830

554

globalfail:

831

555

832

556

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_global_deinit();

833

558

gnutls_dh_params_deinit(mc->dh_params);

834

559

return -1;

835

560

}

836

561

837

__attribute__((nonnull, warn_unused_result))

838

562

static int init_gnutls_session(gnutls_session_t *session,

839

563

mandos_context *mc){

840

564

int ret;

887

611

/* ignore client certificate if any. */

888

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

889

613

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

615

890

616

return 0;

891

617

}

892

618

894

620

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

895

621

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

896

622

897

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

898

__attribute__((warn_unused_result))

899

int raise_privileges(void){

900

int old_errno = errno;

901

int ret = 0;

902

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

903

ret = errno;

904

}

905

errno = old_errno;

906

return ret;

907

}

908

909

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

910

__attribute__((warn_unused_result))

911

int raise_privileges_permanently(void){

912

int old_errno = errno;

913

int ret = raise_privileges();

914

if(ret != 0){

915

errno = old_errno;

916

return ret;

917

}

918

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

919

ret = errno;

920

}

921

errno = old_errno;

922

return ret;

923

}

924

925

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

926

__attribute__((warn_unused_result))

927

int lower_privileges(void){

928

int old_errno = errno;

929

int ret = 0;

930

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

931

ret = errno;

932

}

933

errno = old_errno;

934

return ret;

935

}

936

937

/* Lower privileges permanently */

938

__attribute__((warn_unused_result))

939

int lower_privileges_permanently(void){

940

int old_errno = errno;

941

int ret = 0;

942

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

943

ret = errno;

944

}

945

errno = old_errno;

946

return ret;

947

}

948

949

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

950

__attribute__((nonnull, warn_unused_result))

951

static bool add_delete_local_route(const bool add,

952

const char *address,

953

AvahiIfIndex if_index){

954

int ret;

955

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

956

char add_arg[] = "add";

957

char delete_arg[] = "delete";

958

char debug_flag[] = "--debug";

959

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

960

if(pluginhelperdir == NULL){

961

if(debug){

962

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

963

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

964

}

965

return false;

966

}

967

968

char interface[IF_NAMESIZE];

969

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

970

perror_plus("if_indextoname");

971

return false;

972

}

973

974

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

975

if(devnull == -1){

976

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

977

return false;

978

}

979

pid_t pid = fork();

980

if(pid == 0){

981

/* Child */

982

/* Raise privileges */

983

errno = raise_privileges_permanently();

984

if(errno != 0){

985

perror_plus("Failed to raise privileges");

986

/* _exit(EX_NOPERM); */

987

} else {

988

/* Set group */

989

errno = 0;

990

ret = setgid(0);

991

if(ret == -1){

992

perror_plus("setgid");

993

_exit(EX_NOPERM);

994

}

995

/* Reset supplementary groups */

996

errno = 0;

997

ret = setgroups(0, NULL);

998

if(ret == -1){

999

perror_plus("setgroups");

1000

_exit(EX_NOPERM);

1001

}

1002

}

1003

ret = dup2(devnull, STDIN_FILENO);

1004

if(ret == -1){

1005

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

1006

_exit(EX_OSERR);

1007

}

1008

ret = close(devnull);

1009

if(ret == -1){

1010

perror_plus("close");

1011

_exit(EX_OSERR);

1012

}

1013

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1014

if(ret == -1){

1015

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

1016

_exit(EX_OSERR);

1017

}

1018

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

1019

O_RDONLY

1020

| O_DIRECTORY

1021

| O_PATH

1022

| O_CLOEXEC));

1023

if(helperdir_fd == -1){

1024

perror_plus("open");

1025

_exit(EX_UNAVAILABLE);

1026

}

1027

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

1028

helper, O_RDONLY));

1029

if(helper_fd == -1){

1030

perror_plus("openat");

1031

close(helperdir_fd);

1032

_exit(EX_UNAVAILABLE);

1033

}

1034

close(helperdir_fd);

1035

#ifdef __GNUC__

1036

#pragma GCC diagnostic push

1037

#pragma GCC diagnostic ignored "-Wcast-qual"

1038

#endif

1039

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

1040

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

1041

interface, debug ? debug_flag : NULL, NULL },

1042

environ) == -1){

1043

#ifdef __GNUC__

1044

#pragma GCC diagnostic pop

1045

#endif

1046

perror_plus("fexecve");

1047

_exit(EXIT_FAILURE);

1048

}

1049

}

1050

if(pid == -1){

1051

perror_plus("fork");

1052

return false;

1053

}

1054

int status;

1055

pid_t pret = -1;

1056

errno = 0;

1057

do {

1058

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

1059

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

1060

int errno_raising = 0;

1061

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

1062

errno_raising = errno;

1063

perror_plus("Failed to raise privileges in order to"

1064

" kill helper program");

1065

}

1066

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

1067

perror_plus("kill");

1068

}

1069

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

1070

perror_plus("Failed to lower privileges after killing"

1071

" helper program");

1072

}

1073

return false;

1074

}

1075

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

1076

if(pret == -1){

1077

perror_plus("waitpid");

1078

return false;

1079

}

1080

if(WIFEXITED(status)){

1081

if(WEXITSTATUS(status) != 0){

1082

fprintf_plus(stderr, "Error: iprouteadddel exited"

1083

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

1084

return false;

1085

}

1086

return true;

1087

}

1088

if(WIFSIGNALED(status)){

1089

fprintf_plus(stderr, "Error: iprouteadddel died by"

1090

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

1091

return false;

1092

}

1093

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

1094

return false;

1095

}

1096

1097

__attribute__((nonnull, warn_unused_result))

1098

static bool add_local_route(const char *address,

1099

AvahiIfIndex if_index){

1100

if(debug){

1101

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

1102

}

1103

return add_delete_local_route(true, address, if_index);

1104

}

1105

1106

__attribute__((nonnull, warn_unused_result))

1107

static bool delete_local_route(const char *address,

1108

AvahiIfIndex if_index){

1109

if(debug){

1110

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

1111

}

1112

return add_delete_local_route(false, address, if_index);

1113

}

1114

1115

623

/* Called when a Mandos server is found */

1116

__attribute__((nonnull, warn_unused_result))

1117

624

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

1118

625

AvahiIfIndex if_index,

1119

626

int af, mandos_context *mc){

1120

627

int ret, tcp_sd = -1;

1121

628

ssize_t sret;

1122

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1123

633

char *buffer = NULL;

1124

634

char *decrypted_buffer = NULL;

1125

635

size_t buffer_length = 0;

1128

638

int retval = -1;

1129

639

gnutls_session_t session;

1130

640

int pf; /* Protocol family */

1131

bool route_added = false;

1132

641

1133

642

errno = 0;

1134

643

1156

665

bool match = false;

1157

666

{

1158

667

char *interface = NULL;

1159

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

1160

mc->interfaces_size,

1161

interface))){

668

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

669

interface))){

1162

670

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

1163

671

match = true;

1164

672

break;

1193

701

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

1194

702

}

1195

703

1196

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

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

1197

705

if(tcp_sd < 0){

1198

706

int e = errno;

1199

707

perror_plus("socket");

1206

714

goto mandos_end;

1207

715

}

1208

716

717

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

1209

718

if(af == AF_INET6){

1210

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

1211

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

1212

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);

1213

721

} else { /* IPv4 */

1214

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

1215

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

1216

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);

1217

724

}

1218

725

if(ret < 0 ){

1219

726

int e = errno;

1228

735

goto mandos_end;

1229

736

}

1230

737

if(af == AF_INET6){

1231

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

1232

if(IN6_IS_ADDR_LINKLOCAL

1233

(&((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*/

1234

742

if(if_index == AVAHI_IF_UNSPEC){

1235

743

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

1236

744

" incomplete without a network interface\n");

1238

746

goto mandos_end;

1239

747

}

1240

748

/* Set the network interface number as scope */

1241

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

749

to.in6.sin6_scope_id = (uint32_t)if_index;

1242

750

}

1243

751

} else {

1244

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

752

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

753

-Wconversion and

754

-Wunreachable-code */

1245

755

}

1246

756

1247

757

if(quit_now){

1264

774

}

1265

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1266

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1267

if(af == AF_INET6){

1268

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

1269

sizeof(struct sockaddr_in6),

1270

addrstr, sizeof(addrstr), NULL, 0,

1271

NI_NUMERICHOST);

1272

} else {

1273

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

1274

sizeof(struct sockaddr_in),

1275

addrstr, sizeof(addrstr), NULL, 0,

1276

NI_NUMERICHOST);

1277

}

1278

if(ret == EAI_SYSTEM){

1279

perror_plus("getnameinfo");

1280

} else if(ret != 0) {

1281

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

1282

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

1283

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

1284

}

1285

}

1286

1287

if(quit_now){

1288

errno = EINTR;

1289

goto mandos_end;

1290

}

1291

1292

while(true){

1293

if(af == AF_INET6){

1294

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

1295

sizeof(struct sockaddr_in6));

1296

} else {

1297

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

1298

sizeof(struct sockaddr_in));

1299

}

1300

if(ret < 0){

1301

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

1302

and if_index != AVAHI_IF_UNSPEC

1303

and connect_to == NULL

1304

and not route_added and

1305

((af == AF_INET6 and not

1306

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1307

&to)->sin6_addr)))

1308

or (af == AF_INET and

1309

/* Not a a IPv4LL address */

1310

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

1311

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

1312

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

1313

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

1314

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

1315

connect to a Mandos server announced by Avahi on a server

1316

host with a global address. Work around this by retrying

1317

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

1318

1319

Avahi bug reference:

1320

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

1321

https://bugs.debian.org/587961

1322

*/

1323

if(debug){

1324

fprintf_plus(stderr, "Mandos server unreachable, trying"

1325

" direct route\n");

1326

}

1327

int e = errno;

1328

route_added = add_local_route(ip, if_index);

1329

if(route_added){

1330

continue;

1331

}

1332

errno = e;

1333

}

1334

if(errno != ECONNREFUSED or debug){

1335

int e = errno;

1336

perror_plus("connect");

1337

errno = e;

1338

}

1339

goto mandos_end;

1340

}

1341

1342

if(quit_now){

1343

errno = EINTR;

1344

goto mandos_end;

1345

}

1346

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;

1347

816

}

1348

817

1349

818

const char *out = mandos_protocol_version;

1503

972

&decrypted_buffer, mc);

1504

973

if(decrypted_buffer_size >= 0){

1505

974

1506

clearerr(stdout);

1507

975

written = 0;

1508

976

while(written < (size_t) decrypted_buffer_size){

1509

977

if(quit_now){

1525

993

}

1526

994

written += (size_t)ret;

1527

995

}

1528

ret = fflush(stdout);

1529

if(ret != 0){

1530

int e = errno;

1531

if(debug){

1532

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

1533

strerror(errno));

1534

}

1535

errno = e;

1536

goto mandos_end;

1537

}

1538

996

retval = 0;

1539

997

}

1540

998

}

1543

1001

1544

1002

mandos_end:

1545

1003

{

1546

if(route_added){

1547

if(not delete_local_route(ip, if_index)){

1548

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

1549

" interface %d", ip, if_index);

1550

}

1551

}

1552

1004

int e = errno;

1553

1005

free(decrypted_buffer);

1554

1006

free(buffer);

1555

1007

if(tcp_sd >= 0){

1556

ret = close(tcp_sd);

1008

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

1557

1009

}

1558

1010

if(ret == -1){

1559

1011

if(e == 0){

1584

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

1585

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1586

1038

flags,

1587

void *mc){

1039

void* mc){

1588

1040

if(r == NULL){

1589

1041

return;

1590

1042

}

1593

1045

timed out */

1594

1046

1595

1047

if(quit_now){

1596

avahi_s_service_resolver_free(r);

1597

1048

return;

1598

1049

}

1599

1050

1644

1095

const char *domain,

1645

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1646

1097

flags,

1647

void *mc){

1098

void* mc){

1648

1099

if(b == NULL){

1649

1100

return;

1650

1101

}

1710

1161

errno = old_errno;

1711

1162

}

1712

1163

1713

__attribute__((nonnull, warn_unused_result))

1714

1164

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

1715

1165

int ret;

1716

int old_errno;

1166

error_t ret_errno;

1717

1167

1718

1168

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

1719

1169

if(s < 0){

1720

old_errno = errno;

1170

ret_errno = errno;

1721

1171

perror_plus("socket");

1722

errno = old_errno;

1172

errno = ret_errno;

1723

1173

return false;

1724

1174

}

1725

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

1726

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

1175

strcpy(ifr->ifr_name, ifname);

1727

1176

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1728

1177

if(ret == -1){

1729

1178

if(debug){

1730

old_errno = errno;

1179

ret_errno = errno;

1731

1180

perror_plus("ioctl SIOCGIFFLAGS");

1732

errno = old_errno;

1733

}

1734

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

1735

old_errno = errno;

1736

perror_plus("close");

1737

errno = old_errno;

1181

errno = ret_errno;

1738

1182

}

1739

1183

return false;

1740

1184

}

1741

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

1742

old_errno = errno;

1743

perror_plus("close");

1744

errno = old_errno;

1745

}

1746

1185

return true;

1747

1186

}

1748

1187

1749

__attribute__((nonnull, warn_unused_result))

1750

1188

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

1751

1189

1752

1190

/* Reject the loopback device */

1794

1232

* corresponds to an acceptable network device.

1795

1233

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

1796

1234

*/

1797

__attribute__((nonnull, warn_unused_result))

1798

1235

int good_interface(const struct dirent *if_entry){

1799

1236

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

1800

1237

return 0;

1818

1255

/*

1819

1256

* This function determines if a network interface is up.

1820

1257

*/

1821

__attribute__((nonnull, warn_unused_result))

1822

1258

bool interface_is_up(const char *interface){

1823

1259

struct ifreq ifr;

1824

1260

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

1835

1271

/*

1836

1272

* This function determines if a network interface is running

1837

1273

*/

1838

__attribute__((nonnull, warn_unused_result))

1839

1274

bool interface_is_running(const char *interface){

1840

1275

struct ifreq ifr;

1841

1276

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

1849

1284

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

1850

1285

}

1851

1286

1852

__attribute__((nonnull, pure, warn_unused_result))

1853

1287

int notdotentries(const struct dirent *direntry){

1854

1288

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

1855

1289

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

1862

1296

}

1863

1297

1864

1298

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

1865

__attribute__((nonnull, warn_unused_result))

1866

1299

int runnable_hook(const struct dirent *direntry){

1867

1300

int ret;

1868

1301

size_t sret;

1876

1309

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

1877

1310

"abcdefghijklmnopqrstuvwxyz"

1878

1311

"0123456789"

1879

"_.-");

1312

"_-");

1880

1313

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

1881

1314

/* Contains non-allowed characters */

1882

1315

if(debug){

1886

1319

return 0;

1887

1320

}

1888

1321

1889

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);

1890

1330

if(ret == -1){

1891

1331

if(debug){

1892

1332

perror_plus("Could not stat hook");

1916

1356

return 1;

1917

1357

}

1918

1358

1919

__attribute__((nonnull, warn_unused_result))

1920

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1921

1360

mandos_context *mc){

1922

1361

int ret;

1926

1365

1927

1366

while(true){

1928

1367

if(mc->current_server == NULL){

1929

if(debug){

1368

if (debug){

1930

1369

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

1931

1370

" No timeout!\n");

1932

1371

}

1933

1372

ret = avahi_simple_poll_iterate(s, -1);

1934

1373

} else {

1935

if(debug){

1374

if (debug){

1936

1375

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

1937

1376

" it, or wait\n");

1938

1377

}

1955

1394

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

1956

1395

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

1957

1396

1958

if(debug){

1397

if (debug){

1959

1398

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

1960

1399

block_time);

1961

1400

}

1983

1422

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

1984

1423

}

1985

1424

if(ret != 0){

1986

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

1425

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

1987

1426

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

1988

1427

}

1989

1428

}

1990

1429

}

1991

1430

}

1992

1431

1993

__attribute__((nonnull))

1994

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,

1995

1485

const float delay){

1996

struct dirent **direntries = NULL;

1997

if(hookdir_fd == -1){

1998

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1999

| O_CLOEXEC);

2000

if(hookdir_fd == -1){

2001

if(errno == ENOENT){

2002

if(debug){

2003

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

2004

" found\n", hookdir);

2005

}

2006

} else {

2007

perror_plus("open");

2008

}

2009

return;

2010

}

2011

}

2012

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

2013

if(devnull == -1){

2014

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

2015

return;

2016

}

2017

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

2018

runnable_hook, alphasort);

1486

struct dirent **direntries;

1487

struct dirent *direntry;

1488

int ret;

1489

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

1490

alphasort);

2019

1491

if(numhooks == -1){

2020

perror_plus("scandir");

2021

close(devnull);

2022

return;

2023

}

2024

struct dirent *direntry;

2025

int ret;

2026

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

2027

direntry = direntries[i];

2028

if(debug){

2029

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

2030

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");

2031

1499

}

2032

pid_t hook_pid = fork();

2033

if(hook_pid == 0){

2034

/* Child */

2035

/* Raise privileges */

2036

errno = raise_privileges_permanently();

2037

if(errno != 0){

2038

perror_plus("Failed to raise privileges");

2039

_exit(EX_NOPERM);

2040

}

2041

/* Set group */

2042

errno = 0;

2043

ret = setgid(0);

2044

if(ret == -1){

2045

perror_plus("setgid");

2046

_exit(EX_NOPERM);

2047

}

2048

/* Reset supplementary groups */

2049

errno = 0;

2050

ret = setgroups(0, NULL);

2051

if(ret == -1){

2052

perror_plus("setgroups");

2053

_exit(EX_NOPERM);

2054

}

2055

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

2056

if(ret == -1){

2057

perror_plus("setenv");

2058

_exit(EX_OSERR);

2059

}

2060

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

2061

if(ret == -1){

2062

perror_plus("setenv");

2063

_exit(EX_OSERR);

2064

}

2065

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

2066

if(ret == -1){

2067

perror_plus("setenv");

2068

_exit(EX_OSERR);

2069

}

2070

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

2071

if(ret == -1){

2072

perror_plus("setenv");

2073

_exit(EX_OSERR);

2074

}

2075

char *delaystring;

2076

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

2077

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){

2078

1507

perror_plus("asprintf");

2079

_exit(EX_OSERR);

2080

}

2081

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

2082

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

}

2083

1566

free(delaystring);

2084

perror_plus("setenv");

2085

_exit(EX_OSERR);

2086

}

2087

free(delaystring);

2088

if(connect_to != NULL){

2089

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

2090

if(ret == -1){

2091

perror_plus("setenv");

2092

_exit(EX_OSERR);

2093

}

2094

}

2095

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

2096

direntry->d_name,

2097

O_RDONLY));

2098

if(hook_fd == -1){

2099

perror_plus("openat");

2100

_exit(EXIT_FAILURE);

2101

}

2102

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

2103

perror_plus("close");

2104

_exit(EXIT_FAILURE);

2105

}

2106

ret = dup2(devnull, STDIN_FILENO);

2107

if(ret == -1){

2108

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

2109

_exit(EX_OSERR);

2110

}

2111

ret = close(devnull);

2112

if(ret == -1){

2113

perror_plus("close");

2114

_exit(EX_OSERR);

2115

}

2116

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2117

if(ret == -1){

2118

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

2119

_exit(EX_OSERR);

2120

}

2121

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

2122

environ) == -1){

2123

perror_plus("fexecve");

2124

_exit(EXIT_FAILURE);

2125

}

2126

} else {

2127

if(hook_pid == -1){

2128

perror_plus("fork");

2129

free(direntry);

2130

continue;

2131

}

2132

int status;

2133

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

2134

perror_plus("waitpid");

2135

free(direntry);

2136

continue;

2137

}

2138

if(WIFEXITED(status)){

2139

if(WEXITSTATUS(status) != 0){

2140

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

2141

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

2142

WEXITSTATUS(status));

2143

free(direntry);

2144

continue;

2145

}

2146

} else if(WIFSIGNALED(status)){

2147

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

2148

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

2149

WTERMSIG(status));

2150

free(direntry);

2151

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

}

2152

1578

} else {

2153

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

2154

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

2155

free(direntry);

2156

continue;

2157

}

2158

}

2159

if(debug){

2160

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

2161

direntry->d_name);

2162

}

2163

free(direntry);

2164

}

2165

free(direntries);

2166

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

2167

perror_plus("close");

2168

} else {

2169

hookdir_fd = -1;

2170

}

2171

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;

2172

1615

}

2173

1616

2174

__attribute__((nonnull, warn_unused_result))

2175

int bring_up_interface(const char *const interface,

2176

const float delay){

2177

int old_errno = errno;

2178

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;

2179

1623

struct ifreq network;

2180

1624

unsigned int if_index = if_nametoindex(interface);

2181

1625

if(if_index == 0){

2190

1634

}

2191

1635

2192

1636

if(not interface_is_up(interface)){

2193

int ret_errno = 0;

2194

int ioctl_errno = 0;

2195

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

1637

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

2196

1638

ret_errno = errno;

2197

1639

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

2198

1640

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

2199

errno = old_errno;

2200

1641

return ret_errno;

2201

1642

}

2202

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

1643

network.ifr_flags |= IFF_UP;

2203

1644

2204

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

2205

if(sd == -1){

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

2206

1647

ret_errno = errno;

2207

1648

perror_plus("socket");

2208

1649

errno = old_errno;

2209

1650

return ret_errno;

2210

1651

}

2211

1652

2212

1653

if(quit_now){

2213

ret = close(sd);

2214

if(ret == -1){

2215

perror_plus("close");

2216

}

1654

close(sd);

2217

1655

errno = old_errno;

2218

1656

return EINTR;

2219

1657

}

2223

1661

interface);

2224

1662

}

2225

1663

2226

/* Raise privileges */

2227

ret_errno = raise_privileges();

2228

if(ret_errno != 0){

2229

errno = ret_errno;

2230

perror_plus("Failed to raise privileges");

2231

}

1664

/* Raise priviliges */

1665

raise_privileges();

2232

1666

2233

1667

#ifdef __linux__

2234

int ret_linux;

2235

bool restore_loglevel = false;

2236

if(ret_errno == 0){

2237

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2238

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

2239

ret_linux = klogctl(8, NULL, 5);

2240

if(ret_linux == -1){

2241

perror_plus("klogctl");

2242

} else {

2243

restore_loglevel = true;

2244

}

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");

2245

1675

}

2246

1676

#endif /* __linux__ */

2247

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

2248

ioctl_errno = errno;

1677

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

1678

ret_errno = errno;

2249

1679

#ifdef __linux__

2250

1680

if(restore_loglevel){

2251

1681

ret_linux = klogctl(7, NULL, 0);

2255

1685

}

2256

1686

#endif /* __linux__ */

2257

1687

2258

/* If raise_privileges() succeeded above */

2259

if(ret_errno == 0){

2260

/* Lower privileges */

2261

ret_errno = lower_privileges();

2262

if(ret_errno != 0){

2263

errno = ret_errno;

2264

perror_plus("Failed to lower privileges");

2265

}

2266

}

1688

/* Lower privileges */

1689

lower_privileges();

2267

1690

2268

1691

/* Close the socket */

2269

ret = close(sd);

1692

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

2270

1693

if(ret == -1){

2271

1694

perror_plus("close");

2272

1695

}

2273

1696

2274

1697

if(ret_setflags == -1){

2275

errno = ioctl_errno;

1698

errno = ret_errno;

2276

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2277

1700

errno = old_errno;

2278

return ioctl_errno;

1701

return ret_errno;

2279

1702

}

2280

1703

} else if(debug){

2281

1704

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

2284

1707

2285

1708

/* Sleep checking until interface is running.

2286

1709

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

2287

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

1710

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

2288

1711

if(interface_is_running(interface)){

2289

1712

break;

2290

1713

}

2299

1722

return 0;

2300

1723

}

2301

1724

2302

__attribute__((nonnull, warn_unused_result))

2303

int take_down_interface(const char *const interface){

2304

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;

2305

1730

struct ifreq network;

2306

1731

unsigned int if_index = if_nametoindex(interface);

2307

1732

if(if_index == 0){

2310

1735

return ENXIO;

2311

1736

}

2312

1737

if(interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

1738

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

2316

1739

ret_errno = errno;

2317

1740

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

2318

1741

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

2319

errno = old_errno;

2320

1742

return ret_errno;

2321

1743

}

2322

1744

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

2323

1745

2324

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

2325

if(sd == -1){

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

2326

1748

ret_errno = errno;

2327

1749

perror_plus("socket");

2328

1750

errno = old_errno;

2334

1756

interface);

2335

1757

}

2336

1758

2337

/* Raise privileges */

2338

ret_errno = raise_privileges();

2339

if(ret_errno != 0){

2340

errno = ret_errno;

2341

perror_plus("Failed to raise privileges");

2342

}

2343

2344

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

2345

ioctl_errno = errno;

2346

2347

/* If raise_privileges() succeeded above */

2348

if(ret_errno == 0){

2349

/* Lower privileges */

2350

ret_errno = lower_privileges();

2351

if(ret_errno != 0){

2352

errno = ret_errno;

2353

perror_plus("Failed to lower privileges");

2354

}

2355

}

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();

2356

1767

2357

1768

/* Close the socket */

2358

int ret = close(sd);

1769

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

2359

1770

if(ret == -1){

2360

1771

perror_plus("close");

2361

1772

}

2362

1773

2363

1774

if(ret_setflags == -1){

2364

errno = ioctl_errno;

1775

errno = ret_errno;

2365

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2366

1777

errno = old_errno;

2367

return ioctl_errno;

1778

return ret_errno;

2368

1779

}

2369

1780

} else if(debug){

2370

1781

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

2376

1787

}

2377

1788

2378

1789

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

2379

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

2380

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

2381

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

2382

.current_server = NULL, .interfaces = NULL,

2383

.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 };

2384

1794

AvahiSServiceBrowser *sb = NULL;

2385

1795

error_t ret_errno;

2386

1796

int ret;

2389

1799

int exitcode = EXIT_SUCCESS;

2390

1800

char *interfaces_to_take_down = NULL;

2391

1801

size_t interfaces_to_take_down_size = 0;

2392

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

2393

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

2394

char *tempdir = NULL;

1802

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

1803

bool tempdir_created = false;

2395

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2396

1805

const char *seckey = PATHDIR "/" SECKEY;

2397

1806

const char *pubkey = PATHDIR "/" PUBKEY;

2398

const char *dh_params_file = NULL;

2399

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

2400

1809

2401

1810

bool gnutls_initialized = false;

2402

1811

bool gpgme_initialized = false;

2454

1863

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

2455

1864

" Diffie-Hellman key exchange",

2456

1865

.group = 2 },

2457

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

2458

.arg = "FILE",

2459

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

2460

" for the Diffie-Hellman key exchange",

2461

.group = 2 },

2462

1866

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

2463

1867

.arg = "STRING",

2464

1868

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

2519

1923

}

2520

1924

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

2521

1925

break;

2522

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

2523

dh_params_file = arg;

2524

break;

2525

1926

case 130: /* --priority */

2526

1927

mc.priority = arg;

2527

1928

break;

2567

1968

.args_doc = "",

2568

1969

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

2569

1970

" passwords from a Mandos server" };

2570

ret_errno = argp_parse(&argp, argc, argv,

2571

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2572

switch(ret_errno){

1971

ret = argp_parse(&argp, argc, argv,

1972

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1973

switch(ret){

2573

1974

case 0:

2574

1975

break;

2575

1976

case ENOMEM:

2576

1977

default:

2577

errno = ret_errno;

1978

errno = ret;

2578

1979

perror_plus("argp_parse");

2579

1980

exitcode = EX_OSERR;

2580

1981

goto end;

2583

1984

goto end;

2584

1985

}

2585

1986

}

2586

1987

2587

1988

{

2588

1989

/* Work around Debian bug #633582:

2589

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

1990

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

2590

1991

2591

/* Re-raise privileges */

2592

ret = raise_privileges();

2593

if(ret != 0){

2594

errno = ret;

2595

perror_plus("Failed to raise privileges");

2596

} else {

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2597

1994

struct stat st;

2598

1995

2599

1996

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

2613

2010

}

2614

2011

}

2615

2012

}

2616

close(seckey_fd);

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2617

2014

}

2618

2015

}

2619

2016

2620

2017

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

2621

2018

int pubkey_fd = open(pubkey, O_RDONLY);

2622

2019

if(pubkey_fd == -1){

2634

2031

}

2635

2032

}

2636

2033

}

2637

close(pubkey_fd);

2638

}

2639

}

2640

2641

if(dh_params_file != NULL

2642

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

2643

int dhparams_fd = open(dh_params_file, O_RDONLY);

2644

if(dhparams_fd == -1){

2645

perror_plus("open");

2646

} else {

2647

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

2648

if(ret == -1){

2649

perror_plus("fstat");

2650

} else {

2651

if(S_ISREG(st.st_mode)

2652

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

2653

ret = fchown(dhparams_fd, uid, gid);

2654

if(ret == -1){

2655

perror_plus("fchown");

2656

}

2657

}

2658

}

2659

close(dhparams_fd);

2660

}

2661

}

2662

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2663

2038

/* Lower privileges */

2664

ret = lower_privileges();

2665

if(ret != 0){

2666

errno = ret;

2667

perror_plus("Failed to lower privileges");

2668

}

2039

lower_privileges();

2669

2040

}

2670

2041

}

2671

2042

2695

2066

goto end;

2696

2067

}

2697

2068

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

2698

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

2699

}

2700

run_network_hooks("start", interfaces_hooks != NULL ?

2701

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

}

2702

2077

}

2703

2078

2704

2079

if(not debug){

2782

2157

2783

2158

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

2784

2159

if(mc.interfaces == NULL){

2785

struct dirent **direntries = NULL;

2160

struct dirent **direntries;

2786

2161

/* Look for any good interfaces */

2787

2162

ret = scandir(sys_class_net, &direntries, good_interface,

2788

2163

alphasort);

2792

2167

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

2793

2168

direntries[i]->d_name);

2794

2169

if(ret_errno != 0){

2795

errno = ret_errno;

2796

2170

perror_plus("argz_add");

2797

free(direntries[i]);

2798

2171

continue;

2799

2172

}

2800

2173

if(debug){

2801

2174

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

2802

2175

direntries[i]->d_name);

2803

2176

}

2804

free(direntries[i]);

2805

2177

}

2806

2178

free(direntries);

2807

2179

} else {

2808

if(ret == 0){

2809

free(direntries);

2810

}

2180

free(direntries);

2811

2181

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

2812

2182

exitcode = EXIT_FAILURE;

2813

2183

goto end;

2836

2206

break;

2837

2207

}

2838

2208

bool interface_was_up = interface_is_up(interface);

2839

errno = bring_up_interface(interface, delay);

2209

ret = bring_up_interface(interface, delay);

2840

2210

if(not interface_was_up){

2841

if(errno != 0){

2842

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

2843

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

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2844

2214

} else {

2845

errno = argz_add(&interfaces_to_take_down,

2846

&interfaces_to_take_down_size,

2847

interface);

2848

if(errno != 0){

2849

perror_plus("argz_add");

2850

}

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2851

2218

}

2852

2219

}

2853

2220

}

2869

2236

goto end;

2870

2237

}

2871

2238

2872

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

2239

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

2873

2240

if(ret == -1){

2874

2241

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

2875

2242

exitcode = EX_UNAVAILABLE;

2882

2249

goto end;

2883

2250

}

2884

2251

2885

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

2886

tempdir = mkdtemp(run_tempdir);

2887

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

2888

if(debug){

2889

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

2890

run_tempdir, old_tempdir);

2891

}

2892

tempdir = mkdtemp(old_tempdir);

2893

}

2894

if(tempdir == NULL){

2252

if(mkdtemp(tempdir) == NULL){

2895

2253

perror_plus("mkdtemp");

2896

2254

goto end;

2897

2255

}

2256

tempdir_created = true;

2898

2257

2899

2258

if(quit_now){

2900

2259

goto end;

2972

2331

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

2973

2332

(int)retry_interval);

2974

2333

}

2975

sleep((unsigned int)retry_interval);

2334

sleep((int)retry_interval);

2976

2335

}

2977

2336

2978

if(not quit_now){

2337

if (not quit_now){

2979

2338

exitcode = EXIT_SUCCESS;

2980

2339

}

2981

2340

2997

2356

2998

2357

/* Allocate a new server */

2999

2358

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3000

&config, NULL, NULL, &ret);

2359

&config, NULL, NULL, &ret_errno);

3001

2360

3002

2361

/* Free the Avahi configuration data */

3003

2362

avahi_server_config_free(&config);

3006

2365

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

3007

2366

if(mc.server == NULL){

3008

2367

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

3009

avahi_strerror(ret));

2368

avahi_strerror(ret_errno));

3010

2369

exitcode = EX_UNAVAILABLE;

3011

2370

goto end;

3012

2371

}

3036

2395

if(debug){

3037

2396

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

3038

2397

}

3039

2398

3040

2399

ret = avahi_loop_with_timeout(simple_poll,

3041

2400

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

3042

2401

if(debug){

3047

2406

end:

3048

2407

3049

2408

if(debug){

3050

if(signal_received){

3051

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

3052

argv[0], signal_received,

3053

strsignal(signal_received));

3054

} else {

3055

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

3056

}

2409

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

3057

2410

}

3058

2411

3059

2412

/* Cleanup things */

3070

2423

3071

2424

if(gnutls_initialized){

3072

2425

gnutls_certificate_free_credentials(mc.cred);

2426

gnutls_global_deinit();

3073

2427

gnutls_dh_params_deinit(mc.dh_params);

3074

2428

}

3075

2429

3083

2437

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

3084

2438

while(mc.current_server != NULL){

3085

2439

server *next = mc.current_server->next;

3086

#ifdef __GNUC__

3087

#pragma GCC diagnostic push

3088

#pragma GCC diagnostic ignored "-Wcast-qual"

3089

#endif

3090

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

3091

#ifdef __GNUC__

3092

#pragma GCC diagnostic pop

3093

#endif

3094

2440

free(mc.current_server);

3095

2441

mc.current_server = next;

3096

2442

}

3097

2443

}

3098

2444

3099

/* Re-raise privileges */

2445

/* Re-raise priviliges */

3100

2446

{

3101

ret = raise_privileges();

3102

if(ret != 0){

3103

errno = ret;

3104

perror_plus("Failed to raise privileges");

3105

} else {

3106

3107

/* Run network hooks */

3108

run_network_hooks("stop", interfaces_hooks != NULL ?

3109

interfaces_hooks : "", delay);

3110

3111

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

3112

{

3113

char *interface = NULL;

3114

while((interface = argz_next(interfaces_to_take_down,

3115

interfaces_to_take_down_size,

3116

interface))){

3117

ret = take_down_interface(interface);

3118

if(ret != 0){

3119

errno = ret;

3120

perror_plus("Failed to take down interface");

3121

}

3122

}

3123

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

3124

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

3125

" down\n");

3126

}

3127

}

3128

}

3129

3130

ret = lower_privileges_permanently();

3131

if(ret != 0){

3132

errno = ret;

3133

perror_plus("Failed to lower privileges permanently");

3134

}

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();

3135

2472

}

3136

2473

3137

2474

free(interfaces_to_take_down);

3138

2475

free(interfaces_hooks);

3139

2476

3140

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

3141

uintmax_t level){

2477

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

2478

if(tempdir_created){

3142

2479

struct dirent **direntries = NULL;

3143

int dret;

3144

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

3145

O_RDONLY

3146

| O_NOFOLLOW

3147

| O_DIRECTORY

3148

| O_PATH));

3149

if(dir_fd == -1){

3150

perror_plus("open");

3151

return;

3152

}

3153

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

3154

notdotentries, alphasort);

3155

if(numentries >= 0){

2480

struct dirent *direntry = NULL;

2481

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

2482

alphasort);

2483

if (numentries > 0){

3156

2484

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

3157

if(debug){

3158

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

3159

dirname, direntries[i]->d_name);

3160

}

3161

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

3162

if(dret == -1){

3163

if(errno == EISDIR){

3164

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

3165

AT_REMOVEDIR);

3166

}

3167

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

3168

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

3169

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

3170

/* Recurse only in this special case */

3171

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

3172

dret = 0;

3173

}

3174

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

3175

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

3176

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

3177

}

3178

}

3179

free(direntries[i]);

3180

}

3181

3182

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

3183

free(direntries);

3184

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3185

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

3186

perror_plus("rmdir");

3187

}

3188

} else {

3189

perror_plus("scandirat");

3190

}

3191

close(dir_fd);

3192

}

3193

3194

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

3195

if(tempdir != NULL){

3196

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

}

3197

2511

}

3198

2512

3199

2513

if(quit_now){