/mandos/trunk : revision 710

9

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

10

*

11

* Everything else is

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13

14

*

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* This file is part of Mandos.

16

*

17

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

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

19

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

20

* (at your option) any later version.

21

*

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

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*

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

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

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

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*

20

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

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21

* WITHOUT ANY WARRANTY; without even the implied warranty of

24

22

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

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23

* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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28

*

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29

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

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30

*/

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,

59

57

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

60

58

inet_pton(), connect(),

61

59

getnameinfo() */

62

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

60

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

63

61

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

64

62

*/

65

63

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

66

64

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,

65

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

72

66

program_invocation_short_name */

73

67

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

74

68

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

246

240

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

247

241

if(ret == -1){

248

242

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

243

free(new_server->ip);

257

244

free(new_server);

258

245

return false;

259

246

}

272

259

return true;

273

260

}

274

261

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

262

/*

328

263

* Initialize GPGME.

329

264

*/

349

284

return false;

350

285

}

351

286

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

287

rc = gpgme_data_new_from_fd(&pgp_data, fd);

403

288

if(rc != GPG_ERR_NO_ERROR){

404

289

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

412

297

gpgme_strsource(rc), gpgme_strerror(rc));

413

298

return false;

414

299

}

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

300

491

ret = close(fd);

301

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

492

302

if(ret == -1){

493

303

perror_plus("close");

494

304

}

533

343

/* Create new GPGME "context" */

534

344

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

535

345

if(rc != GPG_ERR_NO_ERROR){

536

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

537

gpgme_strsource(rc), gpgme_strerror(rc));

346

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

347

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

348

gpgme_strerror(rc));

538

349

return false;

539

350

}

540

351

576

387

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

577

388

rc = gpgme_data_new(&dh_plain);

578

389

if(rc != GPG_ERR_NO_ERROR){

579

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

390

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

391

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

580

392

gpgme_strsource(rc), gpgme_strerror(rc));

581

393

gpgme_data_release(dh_crypto);

582

394

return -1;

595

407

if(result == NULL){

596

408

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

597

409

} 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");

410

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

411

result->unsupported_algorithm);

412

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

413

result->wrong_key_usage);

604

414

if(result->file_name != NULL){

605

415

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

606

416

}

607

608

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

609

r = r->next){

417

gpgme_recipient_t recipient;

418

recipient = result->recipients;

419

while(recipient != NULL){

610

420

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);

421

gpgme_pubkey_algo_name

422

(recipient->pubkey_algo));

423

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

613

424

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

614

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

425

recipient->status == GPG_ERR_NO_SECKEY

426

? "No" : "Yes");

427

recipient = recipient->next;

615

428

}

616

429

}

617

430

}

673

486

return plaintext_length;

674

487

}

675

488

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

489

__attribute__((warn_unused_result))

684

490

static const char *safer_gnutls_strerror(int value){

685

491

const char *ret = gnutls_strerror(value);

686

return safe_string(ret);

492

if(ret == NULL)

493

ret = "(unknown)";

494

return ret;

687

495

}

688

496

689

497

/* GnuTLS log function callback */

693

501

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

694

502

}

695

503

696

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

504

__attribute__((nonnull, warn_unused_result))

697

505

static int init_gnutls_global(const char *pubkeyfilename,

698

506

const char *seckeyfilename,

699

const char *dhparamsfilename,

700

507

mandos_context *mc){

701

508

int ret;

702

unsigned int uret;

703

509

704

510

if(debug){

705

511

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

706

512

}

707

513

514

ret = gnutls_global_init();

515

if(ret != GNUTLS_E_SUCCESS){

516

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

517

safer_gnutls_strerror(ret));

518

return -1;

519

}

520

708

521

if(debug){

709

522

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

710

523

* - GnuTLS manual

718

531

if(ret != GNUTLS_E_SUCCESS){

719

532

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

720

533

safer_gnutls_strerror(ret));

534

gnutls_global_deinit();

721

535

return -1;

722

536

}

723

537

748

562

safer_gnutls_strerror(ret));

749

563

goto globalfail;

750

564

}

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

}

565

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

566

if(ret != GNUTLS_E_SUCCESS){

567

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

568

safer_gnutls_strerror(ret));

569

goto globalfail;

570

}

571

928

572

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

929

573

930

574

return 0;

932

576

globalfail:

933

577

934

578

gnutls_certificate_free_credentials(mc->cred);

579

gnutls_global_deinit();

935

580

gnutls_dh_params_deinit(mc->dh_params);

936

581

return -1;

937

582

}

989

634

/* ignore client certificate if any. */

990

635

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

991

636

637

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

638

992

639

return 0;

993

640

}

994

641

996

643

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

997

644

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

998

645

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

646

/* Called when a Mandos server is found */

1166

647

__attribute__((nonnull, warn_unused_result))

1167

648

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

1178

659

int retval = -1;

1179

660

gnutls_session_t session;

1180

661

int pf; /* Protocol family */

1181

bool route_added = false;

1182

662

1183

663

errno = 0;

1184

664

1206

686

bool match = false;

1207

687

{

1208

688

char *interface = NULL;

1209

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

1210

mc->interfaces_size,

1211

interface))){

689

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

690

interface))){

1212

691

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

1213

692

match = true;

1214

693

break;

1243

722

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

1244

723

}

1245

724

1246

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

725

tcp_sd = socket(pf, SOCK_STREAM, 0);

1247

726

if(tcp_sd < 0){

1248

727

int e = errno;

1249

728

perror_plus("socket");

1256

735

goto mandos_end;

1257

736

}

1258

737

738

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

1259

739

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);

740

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

741

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

1263

742

} 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);

743

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

744

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

1267

745

}

1268

746

if(ret < 0 ){

1269

747

int e = errno;

1339

817

goto mandos_end;

1340

818

}

1341

819

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;

820

if(af == AF_INET6){

821

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

822

sizeof(struct sockaddr_in6));

823

} else {

824

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

825

sizeof(struct sockaddr_in));

826

}

827

if(ret < 0){

828

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

829

int e = errno;

830

perror_plus("connect");

831

errno = e;

832

}

833

goto mandos_end;

834

}

835

836

if(quit_now){

837

errno = EINTR;

838

goto mandos_end;

1397

839

}

1398

840

1399

841

const char *out = mandos_protocol_version;

1553

995

&decrypted_buffer, mc);

1554

996

if(decrypted_buffer_size >= 0){

1555

997

1556

clearerr(stdout);

1557

998

written = 0;

1558

999

while(written < (size_t) decrypted_buffer_size){

1559

1000

if(quit_now){

1575

1016

}

1576

1017

written += (size_t)ret;

1577

1018

}

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

1019

retval = 0;

1589

1020

}

1590

1021

}

1593

1024

1594

1025

mandos_end:

1595

1026

{

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

1027

int e = errno;

1603

1028

free(decrypted_buffer);

1604

1029

free(buffer);

1605

1030

if(tcp_sd >= 0){

1606

ret = close(tcp_sd);

1031

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

1607

1032

}

1608

1033

if(ret == -1){

1609

1034

if(e == 0){

1621

1046

return retval;

1622

1047

}

1623

1048

1049

__attribute__((nonnull))

1624

1050

static void resolve_callback(AvahiSServiceResolver *r,

1625

1051

AvahiIfIndex interface,

1626

1052

AvahiProtocol proto,

1643

1069

timed out */

1644

1070

1645

1071

if(quit_now){

1646

avahi_s_service_resolver_free(r);

1647

1072

return;

1648

1073

}

1649

1074

1763

1188

__attribute__((nonnull, warn_unused_result))

1764

1189

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

1765

1190

int ret;

1766

int old_errno;

1191

error_t ret_errno;

1767

1192

1768

1193

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

1769

1194

if(s < 0){

1770

old_errno = errno;

1195

ret_errno = errno;

1771

1196

perror_plus("socket");

1772

errno = old_errno;

1197

errno = ret_errno;

1773

1198

return false;

1774

1199

}

1775

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

1776

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

1200

strcpy(ifr->ifr_name, ifname);

1777

1201

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1778

1202

if(ret == -1){

1779

1203

if(debug){

1780

old_errno = errno;

1204

ret_errno = errno;

1781

1205

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;

1206

errno = ret_errno;

1788

1207

}

1789

1208

return false;

1790

1209

}

1791

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

1792

old_errno = errno;

1793

perror_plus("close");

1794

errno = old_errno;

1795

}

1796

1210

return true;

1797

1211

}

1798

1212

2040

1454

}

2041

1455

}

2042

1456

1457

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

1458

__attribute__((warn_unused_result))

1459

error_t raise_privileges(void){

1460

error_t old_errno = errno;

1461

error_t ret_errno = 0;

1462

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

1463

ret_errno = errno;

1464

}

1465

errno = old_errno;

1466

return ret_errno;

1467

}

1468

1469

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

1470

__attribute__((warn_unused_result))

1471

error_t raise_privileges_permanently(void){

1472

error_t old_errno = errno;

1473

error_t ret_errno = raise_privileges();

1474

if(ret_errno != 0){

1475

errno = old_errno;

1476

return ret_errno;

1477

}

1478

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

1479

ret_errno = errno;

1480

}

1481

errno = old_errno;

1482

return ret_errno;

1483

}

1484

1485

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

1486

__attribute__((warn_unused_result))

1487

error_t lower_privileges(void){

1488

error_t old_errno = errno;

1489

error_t ret_errno = 0;

1490

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

1491

ret_errno = errno;

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

error_t lower_privileges_permanently(void){

1500

error_t old_errno = errno;

1501

error_t ret_errno = 0;

1502

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

1503

ret_errno = errno;

1504

}

1505

errno = old_errno;

1506

return ret_errno;

1507

}

1508

2043

1509

__attribute__((nonnull))

2044

1510

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

2045

1511

const float delay){

2046

1512

struct dirent **direntries = NULL;

2047

1513

if(hookdir_fd == -1){

2048

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2049

| O_CLOEXEC);

1514

hookdir_fd = open(hookdir, O_RDONLY);

2050

1515

if(hookdir_fd == -1){

2051

1516

if(errno == ENOENT){

2052

1517

if(debug){

2059

1524

return;

2060

1525

}

2061

1526

}

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

}

1527

#ifdef __GLIBC__

1528

#if __GLIBC_PREREQ(2, 15)

2067

1529

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

2068

1530

runnable_hook, alphasort);

1531

#else /* not __GLIBC_PREREQ(2, 15) */

1532

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

1533

alphasort);

1534

#endif /* not __GLIBC_PREREQ(2, 15) */

1535

#else /* not __GLIBC__ */

1536

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

1537

alphasort);

1538

#endif /* not __GLIBC__ */

2069

1539

if(numhooks == -1){

2070

1540

perror_plus("scandir");

2071

close(devnull);

2072

1541

return;

2073

1542

}

2074

1543

struct dirent *direntry;

2075

1544

int ret;

1545

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

2076

1546

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

2077

1547

direntry = direntries[i];

2078

1548

if(debug){

2102

1572

perror_plus("setgroups");

2103

1573

_exit(EX_NOPERM);

2104

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

2105

1590

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

2106

1591

if(ret == -1){

2107

1592

perror_plus("setenv");

2142

1627

_exit(EX_OSERR);

2143

1628

}

2144

1629

}

2145

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

2146

direntry->d_name,

2147

O_RDONLY));

1630

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

2148

1631

if(hook_fd == -1){

2149

1632

perror_plus("openat");

2150

1633

_exit(EXIT_FAILURE);

2151

1634

}

2152

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

1635

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

2153

1636

perror_plus("close");

2154

1637

_exit(EXIT_FAILURE);

2155

1638

}

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

1639

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

2172

1640

environ) == -1){

2173

1641

perror_plus("fexecve");

2174

1642

_exit(EXIT_FAILURE);

2175

1643

}

2176

1644

} else {

2177

if(hook_pid == -1){

2178

perror_plus("fork");

2179

free(direntry);

2180

continue;

2181

}

2182

1645

int status;

2183

1646

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

2184

1647

perror_plus("waitpid");

2185

free(direntry);

2186

1648

continue;

2187

1649

}

2188

1650

if(WIFEXITED(status)){

2190

1652

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

2191

1653

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

2192

1654

WEXITSTATUS(status));

2193

free(direntry);

2194

1655

continue;

2195

1656

}

2196

1657

} else if(WIFSIGNALED(status)){

2197

1658

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

2198

1659

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

2199

1660

WTERMSIG(status));

2200

free(direntry);

2201

1661

continue;

2202

1662

} else {

2203

1663

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

2204

1664

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

2205

free(direntry);

2206

1665

continue;

2207

1666

}

2208

1667

}

2210

1669

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

2211

1670

direntry->d_name);

2212

1671

}

2213

free(direntry);

2214

1672

}

2215

1673

free(direntries);

2216

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

1674

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

2217

1675

perror_plus("close");

2218

1676

} else {

2219

1677

hookdir_fd = -1;

2222

1680

}

2223

1681

2224

1682

__attribute__((nonnull, warn_unused_result))

2225

int bring_up_interface(const char *const interface,

2226

const float delay){

2227

int old_errno = errno;

1683

error_t bring_up_interface(const char *const interface,

1684

const float delay){

1685

error_t old_errno = errno;

2228

1686

int ret;

2229

1687

struct ifreq network;

2230

1688

unsigned int if_index = if_nametoindex(interface);

2240

1698

}

2241

1699

2242

1700

if(not interface_is_up(interface)){

2243

int ret_errno = 0;

2244

int ioctl_errno = 0;

1701

error_t ret_errno = 0, ioctl_errno = 0;

2245

1702

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

2246

1703

ret_errno = errno;

2247

1704

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

2260

1717

}

2261

1718

2262

1719

if(quit_now){

2263

ret = close(sd);

1720

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

2264

1721

if(ret == -1){

2265

1722

perror_plus("close");

2266

1723

}

2316

1773

}

2317

1774

2318

1775

/* Close the socket */

2319

ret = close(sd);

1776

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

2320

1777

if(ret == -1){

2321

1778

perror_plus("close");

2322

1779

}

2334

1791

2335

1792

/* Sleep checking until interface is running.

2336

1793

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

2337

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

1794

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

2338

1795

if(interface_is_running(interface)){

2339

1796

break;

2340

1797

}

2350

1807

}

2351

1808

2352

1809

__attribute__((nonnull, warn_unused_result))

2353

int take_down_interface(const char *const interface){

2354

int old_errno = errno;

1810

error_t take_down_interface(const char *const interface){

1811

error_t old_errno = errno;

2355

1812

struct ifreq network;

2356

1813

unsigned int if_index = if_nametoindex(interface);

2357

1814

if(if_index == 0){

2360

1817

return ENXIO;

2361

1818

}

2362

1819

if(interface_is_up(interface)){

2363

int ret_errno = 0;

2364

int ioctl_errno = 0;

1820

error_t ret_errno = 0, ioctl_errno = 0;

2365

1821

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

2366

1822

ret_errno = errno;

2367

1823

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

2405

1861

}

2406

1862

2407

1863

/* Close the socket */

2408

int ret = close(sd);

1864

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

2409

1865

if(ret == -1){

2410

1866

perror_plus("close");

2411

1867

}

2426

1882

}

2427

1883

2428

1884

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 };

1885

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

1886

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

1887

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

1888

.interfaces = NULL, .interfaces_size = 0 };

2434

1889

AvahiSServiceBrowser *sb = NULL;

2435

1890

error_t ret_errno;

2436

1891

int ret;

2445

1900

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2446

1901

const char *seckey = PATHDIR "/" SECKEY;

2447

1902

const char *pubkey = PATHDIR "/" PUBKEY;

2448

const char *dh_params_file = NULL;

2449

1903

char *interfaces_hooks = NULL;

2450

1904

2451

1905

bool gnutls_initialized = false;

2504

1958

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

2505

1959

" Diffie-Hellman key exchange",

2506

1960

.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

1961

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

2513

1962

.arg = "STRING",

2514

1963

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

2569

2018

}

2570

2019

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

2571

2020

break;

2572

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

2573

dh_params_file = arg;

2574

break;

2575

2021

case 130: /* --priority */

2576

2022

mc.priority = arg;

2577

2023

break;

2617

2063

.args_doc = "",

2618

2064

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

2619

2065

" 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){

2066

ret = argp_parse(&argp, argc, argv,

2067

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2068

switch(ret){

2623

2069

case 0:

2624

2070

break;

2625

2071

case ENOMEM:

2626

2072

default:

2627

errno = ret_errno;

2073

errno = ret;

2628

2074

perror_plus("argp_parse");

2629

2075

exitcode = EX_OSERR;

2630

2076

goto end;

2633

2079

goto end;

2634

2080

}

2635

2081

}

2636

2082

2637

2083

{

2638

2084

/* Work around Debian bug #633582:

2639

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

2085

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

2640

2086

2641

2087

/* Re-raise privileges */

2642

ret = raise_privileges();

2643

if(ret != 0){

2644

errno = ret;

2088

ret_errno = raise_privileges();

2089

if(ret_errno != 0){

2090

errno = ret_errno;

2645

2091

perror_plus("Failed to raise privileges");

2646

2092

} else {

2647

2093

struct stat st;

2663

2109

}

2664

2110

}

2665

2111

}

2666

close(seckey_fd);

2112

TEMP_FAILURE_RETRY(close(seckey_fd));

2667

2113

}

2668

2114

}

2669

2115

2670

2116

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

2671

2117

int pubkey_fd = open(pubkey, O_RDONLY);

2672

2118

if(pubkey_fd == -1){

2684

2130

}

2685

2131

}

2686

2132

}

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

2133

TEMP_FAILURE_RETRY(close(pubkey_fd));

2134

}

2135

}

2136

2713

2137

/* Lower privileges */

2714

ret = lower_privileges();

2715

if(ret != 0){

2716

errno = ret;

2138

ret_errno = lower_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2717

2141

perror_plus("Failed to lower privileges");

2718

2142

}

2719

2143

}

2844

2268

if(ret_errno != 0){

2845

2269

errno = ret_errno;

2846

2270

perror_plus("argz_add");

2847

free(direntries[i]);

2848

2271

continue;

2849

2272

}

2850

2273

if(debug){

2851

2274

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

2852

2275

direntries[i]->d_name);

2853

2276

}

2854

free(direntries[i]);

2855

2277

}

2856

2278

free(direntries);

2857

2279

} else {

2889

2311

errno = bring_up_interface(interface, delay);

2890

2312

if(not interface_was_up){

2891

2313

if(errno != 0){

2892

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

2893

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

2314

perror_plus("Failed to bring up interface");

2894

2315

} else {

2895

2316

errno = argz_add(&interfaces_to_take_down,

2896

2317

&interfaces_to_take_down_size,

2919

2340

goto end;

2920

2341

}

2921

2342

2922

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

2343

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

2923

2344

if(ret == -1){

2924

2345

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

2925

2346

exitcode = EX_UNAVAILABLE;

3047

2468

3048

2469

/* Allocate a new server */

3049

2470

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3050

&config, NULL, NULL, &ret);

2471

&config, NULL, NULL, &ret_errno);

3051

2472

3052

2473

/* Free the Avahi configuration data */

3053

2474

avahi_server_config_free(&config);

3056

2477

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

3057

2478

if(mc.server == NULL){

3058

2479

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

3059

avahi_strerror(ret));

2480

avahi_strerror(ret_errno));

3060

2481

exitcode = EX_UNAVAILABLE;

3061

2482

goto end;

3062

2483

}

3097

2518

end:

3098

2519

3099

2520

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

}

2521

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

3107

2522

}

3108

2523

3109

2524

/* Cleanup things */

3120

2535

3121

2536

if(gnutls_initialized){

3122

2537

gnutls_certificate_free_credentials(mc.cred);

2538

gnutls_global_deinit();

3123

2539

gnutls_dh_params_deinit(mc.dh_params);

3124

2540

}

3125

2541

3133

2549

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

3134

2550

while(mc.current_server != NULL){

3135

2551

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

2552

free(mc.current_server);

3145

2553

mc.current_server = next;

3146

2554

}

3148

2556

3149

2557

/* Re-raise privileges */

3150

2558

{

3151

ret = raise_privileges();

3152

if(ret != 0){

3153

errno = ret;

2559

ret_errno = raise_privileges();

2560

if(ret_errno != 0){

2561

errno = ret_errno;

3154

2562

perror_plus("Failed to raise privileges");

3155

2563

} else {

3156

2564

3161

2569

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

3162

2570

{

3163

2571

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;

2572

while((interface=argz_next(interfaces_to_take_down,

2573

interfaces_to_take_down_size,

2574

interface))){

2575

ret_errno = take_down_interface(interface);

2576

if(ret_errno != 0){

2577

errno = ret_errno;

3170

2578

perror_plus("Failed to take down interface");

3171

2579

}

3172

2580

}

3177

2585

}

3178

2586

}

3179

2587

3180

ret = lower_privileges_permanently();

3181

if(ret != 0){

3182

errno = ret;

2588

ret_errno = lower_privileges_permanently();

2589

if(ret_errno != 0){

2590

errno = ret_errno;

3183

2591

perror_plus("Failed to lower privileges permanently");

3184

2592

}

3185

2593

}

3187

2595

free(interfaces_to_take_down);

3188

2596

free(interfaces_hooks);

3189

2597

3190

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

3191

uintmax_t level){

3192

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){

3206

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

2598

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

3245

2599

if(tempdir != NULL){

3246

clean_dir_at(-1, tempdir, 0);

2600

struct dirent **direntries = NULL;

2601

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |

2602

O_NOFOLLOW));

2603

if(tempdir_fd == -1){

2604

perror_plus("open");

2605

} else {

2606

#ifdef __GLIBC__

2607

#if __GLIBC_PREREQ(2, 15)

2608

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

2609

notdotentries, alphasort);

2610

#else /* not __GLIBC_PREREQ(2, 15) */

2611

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

2612

alphasort);

2613

#endif /* not __GLIBC_PREREQ(2, 15) */

2614

#else /* not __GLIBC__ */

2615

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

2616

alphasort);

2617

#endif /* not __GLIBC__ */

2618

if(numentries >= 0){

2619

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

2620

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2621

if(ret == -1){

2622

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2623

" \"%s\", 0): %s\n", tempdir,

2624

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

2625

}

2626

}

2627

2628

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

2629

free(direntries);

2630

if(numentries == -1){

2631

perror_plus("scandir");

2632

}

2633

ret = rmdir(tempdir);

2634

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

2635

perror_plus("rmdir");

2636

}

2637

}

2638

TEMP_FAILURE_RETRY(close(tempdir_fd));

2639

}

3247

2640

}

3248

2641

3249

2642

if(quit_now){