/mandos/trunk : revision 237.4.55

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.

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*

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/>.

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28

*

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29

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

31

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,

123

117

gnutls_*

124

118

init_gnutls_session(),

125

119

GNUTLS_* */

126

#if GNUTLS_VERSION_NUMBER < 0x030600

127

120

#include <gnutls/openpgp.h>

128

121

/* gnutls_certificate_set_openpgp_key_file(),

129

122

GNUTLS_OPENPGP_FMT_BASE64 */

130

#elif GNUTLS_VERSION_NUMBER >= 0x030606

131

#include <gnutls/x509.h> /* gnutls_pkcs_encrypt_flags_t,

132

GNUTLS_PKCS_PLAIN,

133

GNUTLS_PKCS_NULL_PASSWORD */

134

#endif

135

123

136

124

/* GPGME */

137

125

#include <gpgme.h> /* All GPGME types, constants and

145

133

#define PATHDIR "/conf/conf.d/mandos"

146

134

#define SECKEY "seckey.txt"

147

135

#define PUBKEY "pubkey.txt"

148

#define TLS_PRIVKEY "tls-privkey.pem"

149

#define TLS_PUBKEY "tls-pubkey.pem"

150

136

#define HOOKDIR "/lib/mandos/network-hooks.d"

151

137

152

138

bool debug = false;

280

266

return true;

281

267

}

282

268

283

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

286

int old_errno = errno;

287

int ret = 0;

288

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

289

ret = errno;

290

}

291

errno = old_errno;

292

return ret;

293

}

294

295

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

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

298

int old_errno = errno;

299

int ret = raise_privileges();

300

if(ret != 0){

301

errno = old_errno;

302

return ret;

303

}

304

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

305

ret = errno;

306

}

307

errno = old_errno;

308

return ret;

309

}

310

311

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

312

__attribute__((warn_unused_result))

313

int lower_privileges(void){

314

int old_errno = errno;

315

int ret = 0;

316

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

317

ret = errno;

318

}

319

errno = old_errno;

320

return ret;

321

}

322

323

/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

325

int lower_privileges_permanently(void){

326

int old_errno = errno;

327

int ret = 0;

328

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

329

ret = errno;

330

}

331

errno = old_errno;

332

return ret;

333

}

334

335

269

/*

336

270

* Initialize GPGME.

337

271

*/

357

291

return false;

358

292

}

359

293

360

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

361

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

362

do {

363

{

364

time_t currtime = time(NULL);

365

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

366

struct tm tm;

367

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

368

perror_plus("gmtime_r");

369

break;

370

}

371

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

372

break;

373

}

374

if(debug){

375

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

376

}

377

} else {

378

if(debug){

379

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

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

time_t keytime = keystat.st_mtim.tv_sec;

400

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

401

perror_plus("stime");

402

}

403

ret = lower_privileges();

404

if(ret != 0){

405

errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

410

294

rc = gpgme_data_new_from_fd(&pgp_data, fd);

411

295

if(rc != GPG_ERR_NO_ERROR){

412

296

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

420

304

gpgme_strsource(rc), gpgme_strerror(rc));

421

305

return false;

422

306

}

423

{

424

gpgme_import_result_t import_result

425

= gpgme_op_import_result(mc->ctx);

426

if((import_result->imported < 1

427

or import_result->not_imported > 0)

428

and import_result->unchanged == 0){

429

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

430

fprintf_plus(stderr,

431

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

432

import_result->considered);

433

fprintf_plus(stderr,

434

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

435

import_result->no_user_id);

436

fprintf_plus(stderr,

437

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

438

import_result->imported);

439

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

440

import_result->imported_rsa);

441

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

442

import_result->unchanged);

443

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

444

import_result->new_user_ids);

445

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

446

import_result->new_sub_keys);

447

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

448

import_result->new_signatures);

449

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

450

import_result->new_revocations);

451

fprintf_plus(stderr,

452

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

453

import_result->secret_read);

454

fprintf_plus(stderr,

455

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

456

import_result->secret_imported);

457

fprintf_plus(stderr,

458

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

459

import_result->secret_unchanged);

460

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

461

import_result->not_imported);

462

for(gpgme_import_status_t import_status

463

= import_result->imports;

464

import_status != NULL;

465

import_status = import_status->next){

466

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

467

import_status->fpr);

468

if(import_status->result != GPG_ERR_NO_ERROR){

469

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

470

gpgme_strsource(import_status->result),

471

gpgme_strerror(import_status->result));

472

}

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_NEW

476

? "The key was new.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_UID

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SIG

484

? "The key contained new signatures.\n"

485

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

486

fprintf_plus(stderr,

487

import_status->status & GPGME_IMPORT_SUBKEY

488

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

489

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

490

fprintf_plus(stderr,

491

import_status->status & GPGME_IMPORT_SECRET

492

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

493

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

494

}

495

return false;

496

}

497

}

498

307

499

ret = close(fd);

308

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

500

309

if(ret == -1){

501

310

perror_plus("close");

502

311

}

541

350

/* Create new GPGME "context" */

542

351

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

543

352

if(rc != GPG_ERR_NO_ERROR){

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

353

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

354

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

355

gpgme_strerror(rc));

546

356

return false;

547

357

}

548

358

584

394

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

585

395

rc = gpgme_data_new(&dh_plain);

586

396

if(rc != GPG_ERR_NO_ERROR){

587

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

397

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

398

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

588

399

gpgme_strsource(rc), gpgme_strerror(rc));

589

400

gpgme_data_release(dh_crypto);

590

401

return -1;

603

414

if(result == NULL){

604

415

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

605

416

} else {

606

if(result->unsupported_algorithm != NULL) {

607

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

608

result->unsupported_algorithm);

609

}

610

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

611

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

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

612

421

if(result->file_name != NULL){

613

422

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

614

423

}

615

616

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

617

r = r->next){

424

gpgme_recipient_t recipient;

425

recipient = result->recipients;

426

while(recipient != NULL){

618

427

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

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

621

431

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

622

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

434

recipient = recipient->next;

623

435

}

624

436

}

625

437

}

681

493

return plaintext_length;

682

494

}

683

495

684

__attribute__((warn_unused_result, const))

685

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

686

if(str == NULL)

687

return "(unknown)";

688

return str;

689

}

690

691

496

__attribute__((warn_unused_result))

692

497

static const char *safer_gnutls_strerror(int value){

693

498

const char *ret = gnutls_strerror(value);

694

return safe_string(ret);

499

if(ret == NULL)

500

ret = "(unknown)";

501

return ret;

695

502

}

696

503

697

504

/* GnuTLS log function callback */

701

508

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

702

509

}

703

510

704

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

511

__attribute__((nonnull, warn_unused_result))

705

512

static int init_gnutls_global(const char *pubkeyfilename,

706

513

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

514

mandos_context *mc){

709

515

int ret;

710

516

712

518

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

713

519

}

714

520

521

ret = gnutls_global_init();

522

if(ret != GNUTLS_E_SUCCESS){

523

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

524

safer_gnutls_strerror(ret));

525

return -1;

526

}

527

715

528

if(debug){

716

529

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

717

530

* - GnuTLS manual

725

538

if(ret != GNUTLS_E_SUCCESS){

726

539

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

727

540

safer_gnutls_strerror(ret));

541

gnutls_global_deinit();

728

542

return -1;

729

543

}

730

544

731

545

if(debug){

732

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

733

" private key %s as GnuTLS credentials\n",

546

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

547

" secret key %s as GnuTLS credentials\n",

734

548

pubkeyfilename,

735

549

seckeyfilename);

736

550

}

737

551

738

#if GNUTLS_VERSION_NUMBER >= 0x030606

739

ret = gnutls_certificate_set_rawpk_key_file

740

(mc->cred, pubkeyfilename, seckeyfilename,

741

GNUTLS_X509_FMT_PEM, /* format */

742

NULL, /* pass */

743

/* key_usage */

744

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

745

NULL, /* names */

746

0, /* names_length */

747

/* privkey_flags */

748

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

749

0); /* pkcs11_flags */

750

#elif GNUTLS_VERSION_NUMBER < 0x030600

751

552

ret = gnutls_certificate_set_openpgp_key_file

752

553

(mc->cred, pubkeyfilename, seckeyfilename,

753

554

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

757

555

if(ret != GNUTLS_E_SUCCESS){

758

556

fprintf_plus(stderr,

759

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

557

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

760

558

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

761

559

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

762

560

safer_gnutls_strerror(ret));

771

569

safer_gnutls_strerror(ret));

772

570

goto globalfail;

773

571

}

774

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

775

if(dhparamsfilename != NULL){

776

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

777

do {

778

int dhpfile = open(dhparamsfilename, O_RDONLY);

779

if(dhpfile == -1){

780

perror_plus("open");

781

dhparamsfilename = NULL;

782

break;

783

}

784

size_t params_capacity = 0;

785

while(true){

786

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

787

(size_t)params.size,

788

(size_t)params_capacity);

789

if(params_capacity == 0){

790

perror_plus("incbuffer");

791

free(params.data);

792

params.data = NULL;

793

dhparamsfilename = NULL;

794

break;

795

}

796

ssize_t bytes_read = read(dhpfile,

797

params.data + params.size,

798

BUFFER_SIZE);

799

/* EOF */

800

if(bytes_read == 0){

801

break;

802

}

803

/* check bytes_read for failure */

804

if(bytes_read < 0){

805

perror_plus("read");

806

free(params.data);

807

params.data = NULL;

808

dhparamsfilename = NULL;

809

break;

810

}

811

params.size += (unsigned int)bytes_read;

812

}

813

ret = close(dhpfile);

814

if(ret == -1){

815

perror_plus("close");

816

}

817

if(params.data == NULL){

818

dhparamsfilename = NULL;

819

}

820

if(dhparamsfilename == NULL){

821

break;

822

}

823

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

824

GNUTLS_X509_FMT_PEM);

825

if(ret != GNUTLS_E_SUCCESS){

826

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

827

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

828

safer_gnutls_strerror(ret));

829

dhparamsfilename = NULL;

830

}

831

free(params.data);

832

} while(false);

833

}

834

if(dhparamsfilename == NULL){

835

if(mc->dh_bits == 0){

836

#if GNUTLS_VERSION_NUMBER < 0x030600

837

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

838

/* Try to read the private key file */

839

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

840

do {

841

int secfile = open(seckeyfilename, O_RDONLY);

842

if(secfile == -1){

843

perror_plus("open");

844

break;

845

}

846

size_t buffer_capacity = 0;

847

while(true){

848

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

849

(size_t)buffer.size,

850

(size_t)buffer_capacity);

851

if(buffer_capacity == 0){

852

perror_plus("incbuffer");

853

free(buffer.data);

854

buffer.data = NULL;

855

break;

856

}

857

ssize_t bytes_read = read(secfile,

858

buffer.data + buffer.size,

859

BUFFER_SIZE);

860

/* EOF */

861

if(bytes_read == 0){

862

break;

863

}

864

/* check bytes_read for failure */

865

if(bytes_read < 0){

866

perror_plus("read");

867

free(buffer.data);

868

buffer.data = NULL;

869

break;

870

}

871

buffer.size += (unsigned int)bytes_read;

872

}

873

close(secfile);

874

} while(false);

875

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

876

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

877

if(buffer.data != NULL){

878

{

879

gnutls_openpgp_privkey_t privkey = NULL;

880

ret = gnutls_openpgp_privkey_init(&privkey);

881

if(ret != GNUTLS_E_SUCCESS){

882

fprintf_plus(stderr, "Error initializing OpenPGP key"

883

" structure: %s",

884

safer_gnutls_strerror(ret));

885

free(buffer.data);

886

buffer.data = NULL;

887

} else {

888

ret = gnutls_openpgp_privkey_import

889

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

890

if(ret != GNUTLS_E_SUCCESS){

891

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

892

safer_gnutls_strerror(ret));

893

privkey = NULL;

894

}

895

free(buffer.data);

896

buffer.data = NULL;

897

if(privkey != NULL){

898

/* Use private key to suggest an appropriate

899

sec_param */

900

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

901

gnutls_openpgp_privkey_deinit(privkey);

902

if(debug){

903

fprintf_plus(stderr, "This OpenPGP key implies using"

904

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

905

safe_string(gnutls_sec_param_get_name

906

(sec_param)));

907

}

908

}

909

}

910

}

911

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

912

/* Err on the side of caution */

913

sec_param = GNUTLS_SEC_PARAM_ULTRA;

914

if(debug){

915

fprintf_plus(stderr, "Falling back to security parameter"

916

" \"%s\"\n",

917

safe_string(gnutls_sec_param_get_name

918

(sec_param)));

919

}

920

}

921

}

922

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

923

if(uret != 0){

924

mc->dh_bits = uret;

925

if(debug){

926

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

927

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

928

safe_string(gnutls_sec_param_get_name

929

(sec_param)),

930

mc->dh_bits);

931

}

932

} else {

933

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

934

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

935

safe_string(gnutls_sec_param_get_name

936

(sec_param)),

937

safer_gnutls_strerror(ret));

938

goto globalfail;

939

}

940

#endif

941

} else { /* dh_bits != 0 */

942

if(debug){

943

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

944

mc->dh_bits);

945

}

946

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

947

if(ret != GNUTLS_E_SUCCESS){

948

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

949

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

950

safer_gnutls_strerror(ret));

951

goto globalfail;

952

}

953

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

954

}

955

}

572

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

573

if(ret != GNUTLS_E_SUCCESS){

574

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

575

safer_gnutls_strerror(ret));

576

goto globalfail;

577

}

578

579

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

956

580

957

581

return 0;

958

582

959

583

globalfail:

960

584

961

585

gnutls_certificate_free_credentials(mc->cred);

586

gnutls_global_deinit();

962

587

gnutls_dh_params_deinit(mc->dh_params);

963

588

return -1;

964

589

}

969

594

int ret;

970

595

/* GnuTLS session creation */

971

596

do {

972

ret = gnutls_init(session, (GNUTLS_SERVER

973

#if GNUTLS_VERSION_NUMBER >= 0x030506

974

| GNUTLS_NO_TICKETS

975

#endif

976

#if GNUTLS_VERSION_NUMBER >= 0x030606

977

| GNUTLS_ENABLE_RAWPK

978

#endif

979

));

597

ret = gnutls_init(session, GNUTLS_SERVER);

980

598

if(quit_now){

981

599

return -1;

982

600

}

1023

641

/* ignore client certificate if any. */

1024

642

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1025

643

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

645

1026

646

return 0;

1027

647

}

1028

648

1030

650

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

1031

651

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

1032

652

1033

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

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool add_delete_local_route(const bool add,

1036

const char *address,

1037

AvahiIfIndex if_index){

1038

int ret;

1039

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

1040

char add_arg[] = "add";

1041

char delete_arg[] = "delete";

1042

char debug_flag[] = "--debug";

1043

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1044

if(pluginhelperdir == NULL){

1045

if(debug){

1046

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1047

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

1048

}

1049

return false;

1050

}

1051

1052

char interface[IF_NAMESIZE];

1053

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

1054

perror_plus("if_indextoname");

1055

return false;

1056

}

1057

1058

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

1059

if(devnull == -1){

1060

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

1061

return false;

1062

}

1063

pid_t pid = fork();

1064

if(pid == 0){

1065

/* Child */

1066

/* Raise privileges */

1067

errno = raise_privileges_permanently();

1068

if(errno != 0){

1069

perror_plus("Failed to raise privileges");

1070

/* _exit(EX_NOPERM); */

1071

} else {

1072

/* Set group */

1073

errno = 0;

1074

ret = setgid(0);

1075

if(ret == -1){

1076

perror_plus("setgid");

1077

close(devnull);

1078

_exit(EX_NOPERM);

1079

}

1080

/* Reset supplementary groups */

1081

errno = 0;

1082

ret = setgroups(0, NULL);

1083

if(ret == -1){

1084

perror_plus("setgroups");

1085

close(devnull);

1086

_exit(EX_NOPERM);

1087

}

1088

}

1089

ret = dup2(devnull, STDIN_FILENO);

1090

if(ret == -1){

1091

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

1092

close(devnull);

1093

_exit(EX_OSERR);

1094

}

1095

ret = close(devnull);

1096

if(ret == -1){

1097

perror_plus("close");

1098

}

1099

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1100

if(ret == -1){

1101

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

1102

_exit(EX_OSERR);

1103

}

1104

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

1105

O_RDONLY

1106

| O_DIRECTORY

1107

| O_PATH

1108

| O_CLOEXEC));

1109

if(helperdir_fd == -1){

1110

perror_plus("open");

1111

_exit(EX_UNAVAILABLE);

1112

}

1113

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

1114

helper, O_RDONLY));

1115

if(helper_fd == -1){

1116

perror_plus("openat");

1117

close(helperdir_fd);

1118

_exit(EX_UNAVAILABLE);

1119

}

1120

close(helperdir_fd);

1121

#ifdef __GNUC__

1122

#pragma GCC diagnostic push

1123

#pragma GCC diagnostic ignored "-Wcast-qual"

1124

#endif

1125

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

1126

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

1127

interface, debug ? debug_flag : NULL, NULL },

1128

environ) == -1){

1129

#ifdef __GNUC__

1130

#pragma GCC diagnostic pop

1131

#endif

1132

perror_plus("fexecve");

1133

_exit(EXIT_FAILURE);

1134

}

1135

}

1136

if(pid == -1){

1137

perror_plus("fork");

1138

close(devnull);

1139

return false;

1140

}

1141

ret = close(devnull);

1142

if(ret == -1){

1143

perror_plus("close");

1144

}

1145

int status;

1146

pid_t pret = -1;

1147

errno = 0;

1148

do {

1149

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

1150

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

1151

int errno_raising = 0;

1152

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

1153

errno_raising = errno;

1154

perror_plus("Failed to raise privileges in order to"

1155

" kill helper program");

1156

}

1157

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

1158

perror_plus("kill");

1159

}

1160

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

1161

perror_plus("Failed to lower privileges after killing"

1162

" helper program");

1163

}

1164

return false;

1165

}

1166

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

1167

if(pret == -1){

1168

perror_plus("waitpid");

1169

return false;

1170

}

1171

if(WIFEXITED(status)){

1172

if(WEXITSTATUS(status) != 0){

1173

fprintf_plus(stderr, "Error: iprouteadddel exited"

1174

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

1175

return false;

1176

}

1177

return true;

1178

}

1179

if(WIFSIGNALED(status)){

1180

fprintf_plus(stderr, "Error: iprouteadddel died by"

1181

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

1182

return false;

1183

}

1184

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

1185

return false;

1186

}

1187

1188

__attribute__((nonnull, warn_unused_result))

1189

static bool add_local_route(const char *address,

1190

AvahiIfIndex if_index){

1191

if(debug){

1192

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

1193

}

1194

return add_delete_local_route(true, address, if_index);

1195

}

1196

1197

__attribute__((nonnull, warn_unused_result))

1198

static bool delete_local_route(const char *address,

1199

AvahiIfIndex if_index){

1200

if(debug){

1201

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

1202

}

1203

return add_delete_local_route(false, address, if_index);

1204

}

1205

1206

653

/* Called when a Mandos server is found */

1207

654

__attribute__((nonnull, warn_unused_result))

1208

655

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

1219

666

int retval = -1;

1220

667

gnutls_session_t session;

1221

668

int pf; /* Protocol family */

1222

bool route_added = false;

1223

669

1224

670

errno = 0;

1225

671

1247

693

bool match = false;

1248

694

{

1249

695

char *interface = NULL;

1250

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

1251

mc->interfaces_size,

1252

interface))){

696

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

697

interface))){

1253

698

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

1254

699

match = true;

1255

700

break;

1284

729

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

1285

730

}

1286

731

1287

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

732

tcp_sd = socket(pf, SOCK_STREAM, 0);

1288

733

if(tcp_sd < 0){

1289

734

int e = errno;

1290

735

perror_plus("socket");

1297

742

goto mandos_end;

1298

743

}

1299

744

745

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

1300

746

if(af == AF_INET6){

1301

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

1302

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

1303

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

747

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

748

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

1304

749

} else { /* IPv4 */

1305

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

1306

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

1307

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

750

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

751

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

1308

752

}

1309

753

if(ret < 0 ){

1310

754

int e = errno;

1380

824

goto mandos_end;

1381

825

}

1382

826

1383

while(true){

1384

if(af == AF_INET6){

1385

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

1386

sizeof(struct sockaddr_in6));

1387

} else {

1388

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

1389

sizeof(struct sockaddr_in));

1390

}

1391

if(ret < 0){

1392

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

1393

and if_index != AVAHI_IF_UNSPEC

1394

and connect_to == NULL

1395

and not route_added and

1396

((af == AF_INET6 and not

1397

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1398

&to)->sin6_addr)))

1399

or (af == AF_INET and

1400

/* Not a a IPv4LL address */

1401

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

1402

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

1403

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

1404

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

1405

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

1406

connect to a Mandos server announced by Avahi on a server

1407

host with a global address. Work around this by retrying

1408

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

1409

1410

Avahi bug reference:

1411

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

1412

https://bugs.debian.org/587961

1413

*/

1414

if(debug){

1415

fprintf_plus(stderr, "Mandos server unreachable, trying"

1416

" direct route\n");

1417

}

1418

int e = errno;

1419

route_added = add_local_route(ip, if_index);

1420

if(route_added){

1421

continue;

1422

}

1423

errno = e;

1424

}

1425

if(errno != ECONNREFUSED or debug){

1426

int e = errno;

1427

perror_plus("connect");

1428

errno = e;

1429

}

1430

goto mandos_end;

1431

}

1432

1433

if(quit_now){

1434

errno = EINTR;

1435

goto mandos_end;

1436

}

1437

break;

827

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

830

} else {

831

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

832

sizeof(struct sockaddr_in));

833

}

834

if(ret < 0){

835

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

836

int e = errno;

837

perror_plus("connect");

838

errno = e;

839

}

840

goto mandos_end;

841

}

842

843

if(quit_now){

844

errno = EINTR;

845

goto mandos_end;

1438

846

}

1439

847

1440

848

const char *out = mandos_protocol_version;

1594

1002

&decrypted_buffer, mc);

1595

1003

if(decrypted_buffer_size >= 0){

1596

1004

1597

clearerr(stdout);

1598

1005

written = 0;

1599

1006

while(written < (size_t) decrypted_buffer_size){

1600

1007

if(quit_now){

1616

1023

}

1617

1024

written += (size_t)ret;

1618

1025

}

1619

ret = fflush(stdout);

1620

if(ret != 0){

1621

int e = errno;

1622

if(debug){

1623

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

1624

strerror(errno));

1625

}

1626

errno = e;

1627

goto mandos_end;

1628

}

1629

1026

retval = 0;

1630

1027

}

1631

1028

}

1634

1031

1635

1032

mandos_end:

1636

1033

{

1637

if(route_added){

1638

if(not delete_local_route(ip, if_index)){

1639

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

1640

" interface %d", ip, if_index);

1641

}

1642

}

1643

1034

int e = errno;

1644

1035

free(decrypted_buffer);

1645

1036

free(buffer);

1646

1037

if(tcp_sd >= 0){

1647

ret = close(tcp_sd);

1038

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

1648

1039

}

1649

1040

if(ret == -1){

1650

1041

if(e == 0){

1662

1053

return retval;

1663

1054

}

1664

1055

1056

__attribute__((nonnull))

1665

1057

static void resolve_callback(AvahiSServiceResolver *r,

1666

1058

AvahiIfIndex interface,

1667

1059

AvahiProtocol proto,

1804

1196

__attribute__((nonnull, warn_unused_result))

1805

1197

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

1806

1198

int ret;

1807

int old_errno;

1199

error_t ret_errno;

1808

1200

1809

1201

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

1810

1202

if(s < 0){

1811

old_errno = errno;

1203

ret_errno = errno;

1812

1204

perror_plus("socket");

1813

errno = old_errno;

1205

errno = ret_errno;

1814

1206

return false;

1815

1207

}

1816

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

1817

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

1208

strcpy(ifr->ifr_name, ifname);

1818

1209

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1819

1210

if(ret == -1){

1820

1211

if(debug){

1821

old_errno = errno;

1212

ret_errno = errno;

1822

1213

perror_plus("ioctl SIOCGIFFLAGS");

1823

errno = old_errno;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1214

errno = ret_errno;

1829

1215

}

1830

1216

return false;

1831

1217

}

1832

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

1833

old_errno = errno;

1834

perror_plus("close");

1835

errno = old_errno;

1836

}

1837

1218

return true;

1838

1219

}

1839

1220

2081

1462

}

2082

1463

}

2083

1464

1465

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

1466

__attribute__((warn_unused_result))

1467

error_t raise_privileges(void){

1468

error_t old_errno = errno;

1469

error_t ret_errno = 0;

1470

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

1471

ret_errno = errno;

1472

}

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

1477

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

1478

__attribute__((warn_unused_result))

1479

error_t raise_privileges_permanently(void){

1480

error_t old_errno = errno;

1481

error_t ret_errno = raise_privileges();

1482

if(ret_errno != 0){

1483

errno = old_errno;

1484

return ret_errno;

1485

}

1486

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

1487

ret_errno = errno;

1488

}

1489

errno = old_errno;

1490

return ret_errno;

1491

}

1492

1493

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

1494

__attribute__((warn_unused_result))

1495

error_t lower_privileges(void){

1496

error_t old_errno = errno;

1497

error_t ret_errno = 0;

1498

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

1499

ret_errno = errno;

1500

}

1501

errno = old_errno;

1502

return ret_errno;

1503

}

1504

1505

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1507

error_t lower_privileges_permanently(void){

1508

error_t old_errno = errno;

1509

error_t ret_errno = 0;

1510

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

1511

ret_errno = errno;

1512

}

1513

errno = old_errno;

1514

return ret_errno;

1515

}

1516

2084

1517

__attribute__((nonnull))

2085

1518

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

2086

1519

const float delay){

2087

1520

struct dirent **direntries = NULL;

2088

1521

if(hookdir_fd == -1){

2089

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2090

| O_CLOEXEC);

1522

hookdir_fd = open(hookdir, O_RDONLY);

2091

1523

if(hookdir_fd == -1){

2092

1524

if(errno == ENOENT){

2093

1525

if(debug){

2100

1532

return;

2101

1533

}

2102

1534

}

2103

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

2104

if(devnull == -1){

2105

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

2106

return;

2107

}

1535

#ifdef __GLIBC__

1536

#if __GLIBC_PREREQ(2, 15)

2108

1537

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

2109

1538

runnable_hook, alphasort);

1539

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

1540

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

1541

alphasort);

1542

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

1543

#else /* not __GLIBC__ */

1544

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

1545

alphasort);

1546

#endif /* not __GLIBC__ */

2110

1547

if(numhooks == -1){

2111

1548

perror_plus("scandir");

2112

close(devnull);

2113

1549

return;

2114

1550

}

2115

1551

struct dirent *direntry;

2116

1552

int ret;

1553

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

2117

1554

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

2118

1555

direntry = direntries[i];

2119

1556

if(debug){

2143

1580

perror_plus("setgroups");

2144

1581

_exit(EX_NOPERM);

2145

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

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

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

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

1596

_exit(EX_OSERR);

1597

}

2146

1598

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

2147

1599

if(ret == -1){

2148

1600

perror_plus("setenv");

2183

1635

_exit(EX_OSERR);

2184

1636

}

2185

1637

}

2186

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

2187

direntry->d_name,

2188

O_RDONLY));

1638

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

2189

1639

if(hook_fd == -1){

2190

1640

perror_plus("openat");

2191

1641

_exit(EXIT_FAILURE);

2192

1642

}

2193

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

1643

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

2194

1644

perror_plus("close");

2195

1645

_exit(EXIT_FAILURE);

2196

1646

}

2197

ret = dup2(devnull, STDIN_FILENO);

2198

if(ret == -1){

2199

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

2200

_exit(EX_OSERR);

2201

}

2202

ret = close(devnull);

2203

if(ret == -1){

2204

perror_plus("close");

2205

_exit(EX_OSERR);

2206

}

2207

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2208

if(ret == -1){

2209

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

2210

_exit(EX_OSERR);

2211

}

2212

1647

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

2213

1648

environ) == -1){

2214

1649

perror_plus("fexecve");

2254

1689

free(direntry);

2255

1690

}

2256

1691

free(direntries);

2257

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

1692

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

2258

1693

perror_plus("close");

2259

1694

} else {

2260

1695

hookdir_fd = -1;

2263

1698

}

2264

1699

2265

1700

__attribute__((nonnull, warn_unused_result))

2266

int bring_up_interface(const char *const interface,

2267

const float delay){

2268

int old_errno = errno;

1701

error_t bring_up_interface(const char *const interface,

1702

const float delay){

1703

error_t old_errno = errno;

2269

1704

int ret;

2270

1705

struct ifreq network;

2271

1706

unsigned int if_index = if_nametoindex(interface);

2281

1716

}

2282

1717

2283

1718

if(not interface_is_up(interface)){

2284

int ret_errno = 0;

2285

int ioctl_errno = 0;

1719

error_t ret_errno = 0, ioctl_errno = 0;

2286

1720

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

2287

1721

ret_errno = errno;

2288

1722

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

2301

1735

}

2302

1736

2303

1737

if(quit_now){

2304

ret = close(sd);

1738

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

2305

1739

if(ret == -1){

2306

1740

perror_plus("close");

2307

1741

}

2357

1791

}

2358

1792

2359

1793

/* Close the socket */

2360

ret = close(sd);

1794

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

2361

1795

if(ret == -1){

2362

1796

perror_plus("close");

2363

1797

}

2375

1809

2376

1810

/* Sleep checking until interface is running.

2377

1811

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

2378

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

1812

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

2379

1813

if(interface_is_running(interface)){

2380

1814

break;

2381

1815

}

2391

1825

}

2392

1826

2393

1827

__attribute__((nonnull, warn_unused_result))

2394

int take_down_interface(const char *const interface){

2395

int old_errno = errno;

1828

error_t take_down_interface(const char *const interface){

1829

error_t old_errno = errno;

2396

1830

struct ifreq network;

2397

1831

unsigned int if_index = if_nametoindex(interface);

2398

1832

if(if_index == 0){

2401

1835

return ENXIO;

2402

1836

}

2403

1837

if(interface_is_up(interface)){

2404

int ret_errno = 0;

2405

int ioctl_errno = 0;

1838

error_t ret_errno = 0, ioctl_errno = 0;

2406

1839

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

2407

1840

ret_errno = errno;

2408

1841

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

2446

1879

}

2447

1880

2448

1881

/* Close the socket */

2449

int ret = close(sd);

1882

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

2450

1883

if(ret == -1){

2451

1884

perror_plus("close");

2452

1885

}

2467

1900

}

2468

1901

2469

1902

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

2470

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

2471

#if GNUTLS_VERSION_NUMBER >= 0x030606

2472

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

2473

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

2474

":%PROFILE_ULTRA",

2475

#elif GNUTLS_VERSION_NUMBER < 0x030600

2476

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

2477

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

2478

#else

2479

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

2480

#endif

2481

.current_server = NULL, .interfaces = NULL,

2482

.interfaces_size = 0 };

1903

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

1904

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

1905

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

1906

.interfaces = NULL, .interfaces_size = 0 };

2483

1907

AvahiSServiceBrowser *sb = NULL;

2484

1908

error_t ret_errno;

2485

1909

int ret;

2494

1918

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2495

1919

const char *seckey = PATHDIR "/" SECKEY;

2496

1920

const char *pubkey = PATHDIR "/" PUBKEY;

2497

#if GNUTLS_VERSION_NUMBER >= 0x030606

2498

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2499

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2500

#endif

2501

const char *dh_params_file = NULL;

2502

1921

char *interfaces_hooks = NULL;

2503

1922

2504

1923

bool gnutls_initialized = false;

2551

1970

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

2552

1971

.arg = "FILE",

2553

1972

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

2554

.group = 1 },

2555

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

2556

.arg = "FILE",

2557

#if GNUTLS_VERSION_NUMBER >= 0x030606

2558

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

2559

#else

2560

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

2561

#endif

2562

.group = 1 },

2563

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

2564

.arg = "FILE",

2565

#if GNUTLS_VERSION_NUMBER >= 0x030606

2566

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

2567

#else

2568

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

2569

#endif

2570

.group = 1 },

1973

.group = 2 },

2571

1974

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

2572

1975

.arg = "BITS",

2573

1976

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

2574

1977

" Diffie-Hellman key exchange",

2575

1978

.group = 2 },

2576

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

2577

.arg = "FILE",

2578

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

2579

" for the Diffie-Hellman key exchange",

2580

.group = 2 },

2581

1979

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

2582

1980

.arg = "STRING",

2583

1981

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

2629

2027

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

2630

2028

pubkey = arg;

2631

2029

break;

2632

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

2633

#if GNUTLS_VERSION_NUMBER >= 0x030606

2634

tls_privkey = arg;

2635

#endif

2636

break;

2637

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

2638

#if GNUTLS_VERSION_NUMBER >= 0x030606

2639

tls_pubkey = arg;

2640

#endif

2641

break;

2642

2030

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

2643

2031

errno = 0;

2644

2032

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

2648

2036

}

2649

2037

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

2650

2038

break;

2651

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

2652

dh_params_file = arg;

2653

break;

2654

2039

case 130: /* --priority */

2655

2040

mc.priority = arg;

2656

2041

break;

2679

2064

argp_state_help(state, state->out_stream,

2680

2065

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2681

2066

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2682

__builtin_unreachable();

2683

2067

case -3: /* --usage */

2684

2068

argp_state_help(state, state->out_stream,

2685

2069

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2686

__builtin_unreachable();

2687

2070

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

2688

2071

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

2689

2072

exit(argp_err_exit_status);

2698

2081

.args_doc = "",

2699

2082

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

2700

2083

" passwords from a Mandos server" };

2701

ret_errno = argp_parse(&argp, argc, argv,

2702

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2703

switch(ret_errno){

2084

ret = argp_parse(&argp, argc, argv,

2085

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2086

switch(ret){

2704

2087

case 0:

2705

2088

break;

2706

2089

case ENOMEM:

2707

2090

default:

2708

errno = ret_errno;

2091

errno = ret;

2709

2092

perror_plus("argp_parse");

2710

2093

exitcode = EX_OSERR;

2711

2094

goto end;

2714

2097

goto end;

2715

2098

}

2716

2099

}

2717

2100

2718

2101

{

2719

2102

/* Work around Debian bug #633582:

2720

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

2103

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

2721

2104

2722

2105

/* Re-raise privileges */

2723

ret = raise_privileges();

2724

if(ret != 0){

2725

errno = ret;

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2726

2109

perror_plus("Failed to raise privileges");

2727

2110

} else {

2728

2111

struct stat st;

2744

2127

}

2745

2128

}

2746

2129

}

2747

close(seckey_fd);

2130

TEMP_FAILURE_RETRY(close(seckey_fd));

2748

2131

}

2749

2132

}

2750

2133

2751

2134

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

2752

2135

int pubkey_fd = open(pubkey, O_RDONLY);

2753

2136

if(pubkey_fd == -1){

2765

2148

}

2766

2149

}

2767

2150

}

2768

close(pubkey_fd);

2769

}

2770

}

2771

2772

if(dh_params_file != NULL

2773

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

2774

int dhparams_fd = open(dh_params_file, O_RDONLY);

2775

if(dhparams_fd == -1){

2776

perror_plus("open");

2777

} else {

2778

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

2779

if(ret == -1){

2780

perror_plus("fstat");

2781

} else {

2782

if(S_ISREG(st.st_mode)

2783

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

2784

ret = fchown(dhparams_fd, uid, gid);

2785

if(ret == -1){

2786

perror_plus("fchown");

2787

}

2788

}

2789

}

2790

close(dhparams_fd);

2791

}

2792

}

2793

2151

TEMP_FAILURE_RETRY(close(pubkey_fd));

2152

}

2153

}

2154

2794

2155

/* Lower privileges */

2795

ret = lower_privileges();

2796

if(ret != 0){

2797

errno = ret;

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2798

2159

perror_plus("Failed to lower privileges");

2799

2160

}

2800

2161

}

2970

2331

errno = bring_up_interface(interface, delay);

2971

2332

if(not interface_was_up){

2972

2333

if(errno != 0){

2973

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

2974

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

2334

perror_plus("Failed to bring up interface");

2975

2335

} else {

2976

2336

errno = argz_add(&interfaces_to_take_down,

2977

2337

&interfaces_to_take_down_size,

3000

2360

goto end;

3001

2361

}

3002

2362

3003

#if GNUTLS_VERSION_NUMBER >= 0x030606

3004

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

3005

#elif GNUTLS_VERSION_NUMBER < 0x030600

3006

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

3007

#else

3008

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

3009

#endif

2363

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

3010

2364

if(ret == -1){

3011

2365

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

3012

2366

exitcode = EX_UNAVAILABLE;

3134

2488

3135

2489

/* Allocate a new server */

3136

2490

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3137

&config, NULL, NULL, &ret);

2491

&config, NULL, NULL, &ret_errno);

3138

2492

3139

2493

/* Free the Avahi configuration data */

3140

2494

avahi_server_config_free(&config);

3143

2497

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

3144

2498

if(mc.server == NULL){

3145

2499

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

3146

avahi_strerror(ret));

2500

avahi_strerror(ret_errno));

3147

2501

exitcode = EX_UNAVAILABLE;

3148

2502

goto end;

3149

2503

}

3184

2538

end:

3185

2539

3186

2540

if(debug){

3187

if(signal_received){

3188

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

3189

argv[0], signal_received,

3190

strsignal(signal_received));

3191

} else {

3192

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

3193

}

2541

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

3194

2542

}

3195

2543

3196

2544

/* Cleanup things */

3207

2555

3208

2556

if(gnutls_initialized){

3209

2557

gnutls_certificate_free_credentials(mc.cred);

2558

gnutls_global_deinit();

3210

2559

gnutls_dh_params_deinit(mc.dh_params);

3211

2560

}

3212

2561

3235

2584

3236

2585

/* Re-raise privileges */

3237

2586

{

3238

ret = raise_privileges();

3239

if(ret != 0){

3240

errno = ret;

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

3241

2590

perror_plus("Failed to raise privileges");

3242

2591

} else {

3243

2592

3248

2597

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

3249

2598

{

3250

2599

char *interface = NULL;

3251

while((interface = argz_next(interfaces_to_take_down,

3252

interfaces_to_take_down_size,

3253

interface))){

3254

ret = take_down_interface(interface);

3255

if(ret != 0){

3256

errno = ret;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

3257

2606

perror_plus("Failed to take down interface");

3258

2607

}

3259

2608

}

3264

2613

}

3265

2614

}

3266

2615

3267

ret = lower_privileges_permanently();

3268

if(ret != 0){

3269

errno = ret;

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

3270

2619

perror_plus("Failed to lower privileges permanently");

3271

2620

}

3272

2621

}

3274

2623

free(interfaces_to_take_down);

3275

2624

free(interfaces_hooks);

3276

2625

3277

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

3278

uintmax_t level){

3279

struct dirent **direntries = NULL;

3280

int dret;

3281

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

3282

O_RDONLY

3283

| O_NOFOLLOW

3284

| O_DIRECTORY

3285

| O_PATH));

3286

if(dir_fd == -1){

3287

perror_plus("open");

3288

return;

3289

}

3290

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

3291

notdotentries, alphasort);

3292

if(numentries >= 0){

3293

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

3294

if(debug){

3295

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

3296

dirname, direntries[i]->d_name);

3297

}

3298

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

3299

if(dret == -1){

3300

if(errno == EISDIR){

3301

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

3302

AT_REMOVEDIR);

3303

}

3304

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

3305

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

3306

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

3307

/* Recurse only in this special case */

3308

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

3309

dret = 0;

3310

}

3311

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

3312

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

3313

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

3314

}

3315

}

3316

free(direntries[i]);

3317

}

3318

3319

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

3320

free(direntries);

3321

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3322

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

3323

perror_plus("rmdir");

3324

}

3325

} else {

3326

perror_plus("scandirat");

3327

}

3328

close(dir_fd);

3329

}

3330

3331

2626

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

3332

2627

if(tempdir != NULL){

3333

clean_dir_at(-1, tempdir, 0);

2628

struct dirent **direntries = NULL;

2629

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

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

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

2639

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

2640

alphasort);

2641

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

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

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

2649

if(ret == -1){

2650

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

2651

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

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

2666

}

2667

TEMP_FAILURE_RETRY(close(tempdir_fd));

2668

}

3334

2669

}

3335

2670

3336

2671

if(quit_now){