/mandos/release : revision 237.7.498

9

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

10

*

11

* Everything else is

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13

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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

17

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

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

19

*

20

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

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13

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*

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.

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*

22

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

22

24

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

23

25

* General Public License for more details.

24

26

*

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27

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

26

* along with this program. If not, see

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

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

28

29

*

29

30

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

30

31

*/

46

47

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

47

48

strtof(), abort() */

48

49

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

49

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

50

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

50

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

51

asprintf(), strncpy(), strsignal()

52

*/

51

53

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

52

54

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

53

55

sockaddr_in6, PF_INET6,

57

59

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

58

60

inet_pton(), connect(),

59

61

getnameinfo() */

60

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

62

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

61

63

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

62

64

*/

63

65

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

64

66

strtoimax() */

65

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

67

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

68

EAI_SYSTEM, ENETUNREACH,

69

EHOSTUNREACH, ECONNREFUSED, EPROTO,

70

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

71

ENOTEMPTY,

66

72

program_invocation_short_name */

67

73

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

68

74

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

234

240

.af = af };

235

241

if(new_server->ip == NULL){

236

242

perror_plus("strdup");

243

free(new_server);

237

244

return false;

238

245

}

239

246

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

240

247

if(ret == -1){

241

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

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

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

242

258

return false;

243

259

}

244

260

/* Special case of first server */

294

310

gpgme_strsource(rc), gpgme_strerror(rc));

295

311

return false;

296

312

}

313

{

314

gpgme_import_result_t import_result

315

= gpgme_op_import_result(mc->ctx);

316

if((import_result->imported < 1

317

or import_result->not_imported > 0)

318

and import_result->unchanged == 0){

319

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

320

fprintf_plus(stderr,

321

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

322

import_result->considered);

323

fprintf_plus(stderr,

324

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

325

import_result->no_user_id);

326

fprintf_plus(stderr,

327

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

328

import_result->imported);

329

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

330

import_result->imported_rsa);

331

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

332

import_result->unchanged);

333

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

334

import_result->new_user_ids);

335

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

336

import_result->new_sub_keys);

337

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

338

import_result->new_signatures);

339

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

340

import_result->new_revocations);

341

fprintf_plus(stderr,

342

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

343

import_result->secret_read);

344

fprintf_plus(stderr,

345

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

346

import_result->secret_imported);

347

fprintf_plus(stderr,

348

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

349

import_result->secret_unchanged);

350

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

351

import_result->not_imported);

352

for(gpgme_import_status_t import_status

353

= import_result->imports;

354

import_status != NULL;

355

import_status = import_status->next){

356

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

357

import_status->fpr);

358

if(import_status->result != GPG_ERR_NO_ERROR){

359

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

360

gpgme_strsource(import_status->result),

361

gpgme_strerror(import_status->result));

362

}

363

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

364

fprintf_plus(stderr,

365

import_status->status & GPGME_IMPORT_NEW

366

? "The key was new.\n"

367

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

368

fprintf_plus(stderr,

369

import_status->status & GPGME_IMPORT_UID

370

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

371

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

372

fprintf_plus(stderr,

373

import_status->status & GPGME_IMPORT_SIG

374

? "The key contained new signatures.\n"

375

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

376

fprintf_plus(stderr,

377

import_status->status & GPGME_IMPORT_SUBKEY

378

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

379

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

380

fprintf_plus(stderr,

381

import_status->status & GPGME_IMPORT_SECRET

382

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

383

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

384

}

385

return false;

386

}

387

}

297

388

298

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

389

ret = close(fd);

299

390

if(ret == -1){

300

391

perror_plus("close");

301

392

}

340

431

/* Create new GPGME "context" */

341

432

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

342

433

if(rc != GPG_ERR_NO_ERROR){

343

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

344

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

345

gpgme_strerror(rc));

434

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

435

gpgme_strsource(rc), gpgme_strerror(rc));

346

436

return false;

347

437

}

348

438

384

474

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

385

475

rc = gpgme_data_new(&dh_plain);

386

476

if(rc != GPG_ERR_NO_ERROR){

387

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

388

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

477

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

389

478

gpgme_strsource(rc), gpgme_strerror(rc));

390

479

gpgme_data_release(dh_crypto);

391

480

return -1;

404

493

if(result == NULL){

405

494

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

406

495

} else {

407

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

408

result->unsupported_algorithm);

409

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

410

result->wrong_key_usage);

496

if(result->unsupported_algorithm != NULL) {

497

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

498

result->unsupported_algorithm);

499

}

500

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

501

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

411

502

if(result->file_name != NULL){

412

503

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

413

504

}

414

gpgme_recipient_t recipient;

415

recipient = result->recipients;

416

while(recipient != NULL){

505

506

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

507

r = r->next){

417

508

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

418

gpgme_pubkey_algo_name

419

(recipient->pubkey_algo));

420

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

509

gpgme_pubkey_algo_name(r->pubkey_algo));

510

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

421

511

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

422

recipient->status == GPG_ERR_NO_SECKEY

423

? "No" : "Yes");

424

recipient = recipient->next;

512

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

425

513

}

426

514

}

427

515

}

483

571

return plaintext_length;

484

572

}

485

573

574

__attribute__((warn_unused_result, const))

575

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

576

if(str == NULL)

577

return "(unknown)";

578

return str;

579

}

580

486

581

__attribute__((warn_unused_result))

487

582

static const char *safer_gnutls_strerror(int value){

488

583

const char *ret = gnutls_strerror(value);

489

if(ret == NULL)

490

ret = "(unknown)";

491

return ret;

584

return safe_string(ret);

492

585

}

493

586

494

587

/* GnuTLS log function callback */

498

591

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

499

592

}

500

593

501

__attribute__((nonnull, warn_unused_result))

594

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

502

595

static int init_gnutls_global(const char *pubkeyfilename,

503

596

const char *seckeyfilename,

597

const char *dhparamsfilename,

504

598

mandos_context *mc){

505

599

int ret;

600

unsigned int uret;

506

601

507

602

if(debug){

508

603

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

509

604

}

510

605

511

ret = gnutls_global_init();

512

if(ret != GNUTLS_E_SUCCESS){

513

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

514

safer_gnutls_strerror(ret));

515

return -1;

516

}

517

518

606

if(debug){

519

607

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

520

608

* - GnuTLS manual

528

616

if(ret != GNUTLS_E_SUCCESS){

529

617

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

530

618

safer_gnutls_strerror(ret));

531

gnutls_global_deinit();

532

619

return -1;

533

620

}

534

621

559

646

safer_gnutls_strerror(ret));

560

647

goto globalfail;

561

648

}

562

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

563

if(ret != GNUTLS_E_SUCCESS){

564

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

565

safer_gnutls_strerror(ret));

566

goto globalfail;

567

}

568

649

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

650

if(dhparamsfilename != NULL){

651

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

652

do {

653

int dhpfile = open(dhparamsfilename, O_RDONLY);

654

if(dhpfile == -1){

655

perror_plus("open");

656

dhparamsfilename = NULL;

657

break;

658

}

659

size_t params_capacity = 0;

660

while(true){

661

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

662

(size_t)params.size,

663

(size_t)params_capacity);

664

if(params_capacity == 0){

665

perror_plus("incbuffer");

666

free(params.data);

667

params.data = NULL;

668

dhparamsfilename = NULL;

669

break;

670

}

671

ssize_t bytes_read = read(dhpfile,

672

params.data + params.size,

673

BUFFER_SIZE);

674

/* EOF */

675

if(bytes_read == 0){

676

break;

677

}

678

/* check bytes_read for failure */

679

if(bytes_read < 0){

680

perror_plus("read");

681

free(params.data);

682

params.data = NULL;

683

dhparamsfilename = NULL;

684

break;

685

}

686

params.size += (unsigned int)bytes_read;

687

}

688

ret = close(dhpfile);

689

if(ret == -1){

690

perror_plus("close");

691

}

692

if(params.data == NULL){

693

dhparamsfilename = NULL;

694

}

695

if(dhparamsfilename == NULL){

696

break;

697

}

698

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

699

GNUTLS_X509_FMT_PEM);

700

if(ret != GNUTLS_E_SUCCESS){

701

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

702

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

703

safer_gnutls_strerror(ret));

704

dhparamsfilename = NULL;

705

}

706

free(params.data);

707

} while(false);

708

}

709

if(dhparamsfilename == NULL){

710

if(mc->dh_bits == 0){

711

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

712

/* Try to read the private key file */

713

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

714

do {

715

int secfile = open(seckeyfilename, O_RDONLY);

716

if(secfile == -1){

717

perror_plus("open");

718

break;

719

}

720

size_t buffer_capacity = 0;

721

while(true){

722

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

723

(size_t)buffer.size,

724

(size_t)buffer_capacity);

725

if(buffer_capacity == 0){

726

perror_plus("incbuffer");

727

free(buffer.data);

728

buffer.data = NULL;

729

break;

730

}

731

ssize_t bytes_read = read(secfile,

732

buffer.data + buffer.size,

733

BUFFER_SIZE);

734

/* EOF */

735

if(bytes_read == 0){

736

break;

737

}

738

/* check bytes_read for failure */

739

if(bytes_read < 0){

740

perror_plus("read");

741

free(buffer.data);

742

buffer.data = NULL;

743

break;

744

}

745

buffer.size += (unsigned int)bytes_read;

746

}

747

close(secfile);

748

} while(false);

749

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

750

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

751

if(buffer.data != NULL){

752

{

753

gnutls_openpgp_privkey_t privkey = NULL;

754

ret = gnutls_openpgp_privkey_init(&privkey);

755

if(ret != GNUTLS_E_SUCCESS){

756

fprintf_plus(stderr, "Error initializing OpenPGP key"

757

" structure: %s",

758

safer_gnutls_strerror(ret));

759

free(buffer.data);

760

buffer.data = NULL;

761

} else {

762

ret = gnutls_openpgp_privkey_import

763

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

764

if(ret != GNUTLS_E_SUCCESS){

765

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

766

safer_gnutls_strerror(ret));

767

privkey = NULL;

768

}

769

free(buffer.data);

770

buffer.data = NULL;

771

if(privkey != NULL){

772

/* Use private key to suggest an appropriate

773

sec_param */

774

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

775

gnutls_openpgp_privkey_deinit(privkey);

776

if(debug){

777

fprintf_plus(stderr, "This OpenPGP key implies using"

778

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

779

safe_string(gnutls_sec_param_get_name

780

(sec_param)));

781

}

782

}

783

}

784

}

785

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

786

/* Err on the side of caution */

787

sec_param = GNUTLS_SEC_PARAM_ULTRA;

788

if(debug){

789

fprintf_plus(stderr, "Falling back to security parameter"

790

" \"%s\"\n",

791

safe_string(gnutls_sec_param_get_name

792

(sec_param)));

793

}

794

}

795

}

796

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

797

if(uret != 0){

798

mc->dh_bits = uret;

799

if(debug){

800

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

801

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

802

safe_string(gnutls_sec_param_get_name

803

(sec_param)),

804

mc->dh_bits);

805

}

806

} else {

807

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

808

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

809

safe_string(gnutls_sec_param_get_name

810

(sec_param)),

811

safer_gnutls_strerror(ret));

812

goto globalfail;

813

}

814

} else if(debug){

815

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

816

mc->dh_bits);

817

}

818

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

819

if(ret != GNUTLS_E_SUCCESS){

820

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

821

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

822

safer_gnutls_strerror(ret));

823

goto globalfail;

824

}

825

}

569

826

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

570

827

571

828

return 0;

573

830

globalfail:

574

831

575

832

gnutls_certificate_free_credentials(mc->cred);

576

gnutls_global_deinit();

577

833

gnutls_dh_params_deinit(mc->dh_params);

578

834

return -1;

579

835

}

631

887

/* ignore client certificate if any. */

632

888

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

633

889

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

635

636

890

return 0;

637

891

}

638

892

640

894

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

641

895

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

642

896

897

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

898

__attribute__((warn_unused_result))

899

int raise_privileges(void){

900

int old_errno = errno;

901

int ret = 0;

902

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

903

ret = errno;

904

}

905

errno = old_errno;

906

return ret;

907

}

908

909

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

910

__attribute__((warn_unused_result))

911

int raise_privileges_permanently(void){

912

int old_errno = errno;

913

int ret = raise_privileges();

914

if(ret != 0){

915

errno = old_errno;

916

return ret;

917

}

918

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

919

ret = errno;

920

}

921

errno = old_errno;

922

return ret;

923

}

924

925

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

926

__attribute__((warn_unused_result))

927

int lower_privileges(void){

928

int old_errno = errno;

929

int ret = 0;

930

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

931

ret = errno;

932

}

933

errno = old_errno;

934

return ret;

935

}

936

937

/* Lower privileges permanently */

938

__attribute__((warn_unused_result))

939

int lower_privileges_permanently(void){

940

int old_errno = errno;

941

int ret = 0;

942

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

943

ret = errno;

944

}

945

errno = old_errno;

946

return ret;

947

}

948

949

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

950

__attribute__((nonnull, warn_unused_result))

951

static bool add_delete_local_route(const bool add,

952

const char *address,

953

AvahiIfIndex if_index){

954

int ret;

955

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

956

char add_arg[] = "add";

957

char delete_arg[] = "delete";

958

char debug_flag[] = "--debug";

959

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

960

if(pluginhelperdir == NULL){

961

if(debug){

962

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

963

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

964

}

965

return false;

966

}

967

968

char interface[IF_NAMESIZE];

969

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

970

perror_plus("if_indextoname");

971

return false;

972

}

973

974

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

975

if(devnull == -1){

976

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

977

return false;

978

}

979

pid_t pid = fork();

980

if(pid == 0){

981

/* Child */

982

/* Raise privileges */

983

errno = raise_privileges_permanently();

984

if(errno != 0){

985

perror_plus("Failed to raise privileges");

986

/* _exit(EX_NOPERM); */

987

} else {

988

/* Set group */

989

errno = 0;

990

ret = setgid(0);

991

if(ret == -1){

992

perror_plus("setgid");

993

_exit(EX_NOPERM);

994

}

995

/* Reset supplementary groups */

996

errno = 0;

997

ret = setgroups(0, NULL);

998

if(ret == -1){

999

perror_plus("setgroups");

1000

_exit(EX_NOPERM);

1001

}

1002

}

1003

ret = dup2(devnull, STDIN_FILENO);

1004

if(ret == -1){

1005

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

1006

_exit(EX_OSERR);

1007

}

1008

ret = close(devnull);

1009

if(ret == -1){

1010

perror_plus("close");

1011

_exit(EX_OSERR);

1012

}

1013

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1014

if(ret == -1){

1015

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

1016

_exit(EX_OSERR);

1017

}

1018

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

1019

O_RDONLY

1020

| O_DIRECTORY

1021

| O_PATH

1022

| O_CLOEXEC));

1023

if(helperdir_fd == -1){

1024

perror_plus("open");

1025

_exit(EX_UNAVAILABLE);

1026

}

1027

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

1028

helper, O_RDONLY));

1029

if(helper_fd == -1){

1030

perror_plus("openat");

1031

close(helperdir_fd);

1032

_exit(EX_UNAVAILABLE);

1033

}

1034

close(helperdir_fd);

1035

#ifdef __GNUC__

1036

#pragma GCC diagnostic push

1037

#pragma GCC diagnostic ignored "-Wcast-qual"

1038

#endif

1039

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

1040

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

1041

interface, debug ? debug_flag : NULL, NULL },

1042

environ) == -1){

1043

#ifdef __GNUC__

1044

#pragma GCC diagnostic pop

1045

#endif

1046

perror_plus("fexecve");

1047

_exit(EXIT_FAILURE);

1048

}

1049

}

1050

if(pid == -1){

1051

perror_plus("fork");

1052

return false;

1053

}

1054

int status;

1055

pid_t pret = -1;

1056

errno = 0;

1057

do {

1058

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

1059

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

1060

int errno_raising = 0;

1061

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

1062

errno_raising = errno;

1063

perror_plus("Failed to raise privileges in order to"

1064

" kill helper program");

1065

}

1066

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

1067

perror_plus("kill");

1068

}

1069

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

1070

perror_plus("Failed to lower privileges after killing"

1071

" helper program");

1072

}

1073

return false;

1074

}

1075

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

1076

if(pret == -1){

1077

perror_plus("waitpid");

1078

return false;

1079

}

1080

if(WIFEXITED(status)){

1081

if(WEXITSTATUS(status) != 0){

1082

fprintf_plus(stderr, "Error: iprouteadddel exited"

1083

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

1084

return false;

1085

}

1086

return true;

1087

}

1088

if(WIFSIGNALED(status)){

1089

fprintf_plus(stderr, "Error: iprouteadddel died by"

1090

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

1091

return false;

1092

}

1093

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

1094

return false;

1095

}

1096

1097

__attribute__((nonnull, warn_unused_result))

1098

static bool add_local_route(const char *address,

1099

AvahiIfIndex if_index){

1100

if(debug){

1101

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

1102

}

1103

return add_delete_local_route(true, address, if_index);

1104

}

1105

1106

__attribute__((nonnull, warn_unused_result))

1107

static bool delete_local_route(const char *address,

1108

AvahiIfIndex if_index){

1109

if(debug){

1110

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

1111

}

1112

return add_delete_local_route(false, address, if_index);

1113

}

1114

643

1115

/* Called when a Mandos server is found */

644

1116

__attribute__((nonnull, warn_unused_result))

645

1117

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

656

1128

int retval = -1;

657

1129

gnutls_session_t session;

658

1130

int pf; /* Protocol family */

1131

bool route_added = false;

659

1132

660

1133

errno = 0;

661

1134

683

1156

bool match = false;

684

1157

{

685

1158

char *interface = NULL;

686

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

687

interface))){

1159

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

1160

mc->interfaces_size,

1161

interface))){

688

1162

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

689

1163

match = true;

690

1164

break;

719

1193

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

720

1194

}

721

1195

722

tcp_sd = socket(pf, SOCK_STREAM, 0);

1196

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

723

1197

if(tcp_sd < 0){

724

1198

int e = errno;

725

1199

perror_plus("socket");

732

1206

goto mandos_end;

733

1207

}

734

1208

735

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

736

1209

if(af == AF_INET6){

737

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

738

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

1210

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

1211

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

1212

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

739

1213

} else { /* IPv4 */

740

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

741

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

1214

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

1215

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

1216

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

742

1217

}

743

1218

if(ret < 0 ){

744

1219

int e = errno;

814

1289

goto mandos_end;

815

1290

}

816

1291

817

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

820

} else {

821

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

822

sizeof(struct sockaddr_in));

823

}

824

if(ret < 0){

825

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

826

int e = errno;

827

perror_plus("connect");

828

errno = e;

829

}

830

goto mandos_end;

831

}

832

833

if(quit_now){

834

errno = EINTR;

835

goto mandos_end;

1292

while(true){

1293

if(af == AF_INET6){

1294

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

1295

sizeof(struct sockaddr_in6));

1296

} else {

1297

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

1298

sizeof(struct sockaddr_in));

1299

}

1300

if(ret < 0){

1301

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

1302

and if_index != AVAHI_IF_UNSPEC

1303

and connect_to == NULL

1304

and not route_added and

1305

((af == AF_INET6 and not

1306

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1307

&to)->sin6_addr)))

1308

or (af == AF_INET and

1309

/* Not a a IPv4LL address */

1310

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

1311

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

1312

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

1313

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

1314

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

1315

connect to a Mandos server announced by Avahi on a server

1316

host with a global address. Work around this by retrying

1317

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

1318

1319

Avahi bug reference:

1320

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

1321

https://bugs.debian.org/587961

1322

*/

1323

if(debug){

1324

fprintf_plus(stderr, "Mandos server unreachable, trying"

1325

" direct route\n");

1326

}

1327

int e = errno;

1328

route_added = add_local_route(ip, if_index);

1329

if(route_added){

1330

continue;

1331

}

1332

errno = e;

1333

}

1334

if(errno != ECONNREFUSED or debug){

1335

int e = errno;

1336

perror_plus("connect");

1337

errno = e;

1338

}

1339

goto mandos_end;

1340

}

1341

1342

if(quit_now){

1343

errno = EINTR;

1344

goto mandos_end;

1345

}

1346

break;

836

1347

}

837

1348

838

1349

const char *out = mandos_protocol_version;

992

1503

&decrypted_buffer, mc);

993

1504

if(decrypted_buffer_size >= 0){

994

1505

1506

clearerr(stdout);

995

1507

written = 0;

996

1508

while(written < (size_t) decrypted_buffer_size){

997

1509

if(quit_now){

1013

1525

}

1014

1526

written += (size_t)ret;

1015

1527

}

1528

ret = fflush(stdout);

1529

if(ret != 0){

1530

int e = errno;

1531

if(debug){

1532

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

1533

strerror(errno));

1534

}

1535

errno = e;

1536

goto mandos_end;

1537

}

1016

1538

retval = 0;

1017

1539

}

1018

1540

}

1021

1543

1022

1544

mandos_end:

1023

1545

{

1546

if(route_added){

1547

if(not delete_local_route(ip, if_index)){

1548

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

1549

" interface %d", ip, if_index);

1550

}

1551

}

1024

1552

int e = errno;

1025

1553

free(decrypted_buffer);

1026

1554

free(buffer);

1027

1555

if(tcp_sd >= 0){

1028

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

1556

ret = close(tcp_sd);

1029

1557

}

1030

1558

if(ret == -1){

1031

1559

if(e == 0){

1043

1571

return retval;

1044

1572

}

1045

1573

1046

__attribute__((nonnull))

1047

1574

static void resolve_callback(AvahiSServiceResolver *r,

1048

1575

AvahiIfIndex interface,

1049

1576

AvahiProtocol proto,

1066

1593

timed out */

1067

1594

1068

1595

if(quit_now){

1596

avahi_s_service_resolver_free(r);

1069

1597

return;

1070

1598

}

1071

1599

1185

1713

__attribute__((nonnull, warn_unused_result))

1186

1714

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

1187

1715

int ret;

1188

error_t ret_errno;

1716

int old_errno;

1189

1717

1190

1718

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

1191

1719

if(s < 0){

1192

ret_errno = errno;

1720

old_errno = errno;

1193

1721

perror_plus("socket");

1194

errno = ret_errno;

1722

errno = old_errno;

1195

1723

return false;

1196

1724

}

1197

strcpy(ifr->ifr_name, ifname);

1725

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

1726

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

1198

1727

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1199

1728

if(ret == -1){

1200

1729

if(debug){

1201

ret_errno = errno;

1730

old_errno = errno;

1202

1731

perror_plus("ioctl SIOCGIFFLAGS");

1203

errno = ret_errno;

1732

errno = old_errno;

1733

}

1734

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

1735

old_errno = errno;

1736

perror_plus("close");

1737

errno = old_errno;

1204

1738

}

1205

1739

return false;

1206

1740

}

1741

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

1742

old_errno = errno;

1743

perror_plus("close");

1744

errno = old_errno;

1745

}

1207

1746

return true;

1208

1747

}

1209

1748

1451

1990

}

1452

1991

}

1453

1992

1454

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

1455

__attribute__((warn_unused_result))

1456

error_t raise_privileges(void){

1457

error_t old_errno = errno;

1458

error_t ret_errno = 0;

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

__attribute__((warn_unused_result))

1469

error_t raise_privileges_permanently(void){

1470

error_t old_errno = errno;

1471

error_t ret_errno = raise_privileges();

1472

if(ret_errno != 0){

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

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

1477

ret_errno = errno;

1478

perror_plus("seteuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

__attribute__((warn_unused_result))

1486

error_t lower_privileges(void){

1487

error_t old_errno = errno;

1488

error_t ret_errno = 0;

1489

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

1490

ret_errno = errno;

1491

perror_plus("seteuid");

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

perror_plus("setuid");

1505

}

1506

errno = old_errno;

1507

return ret_errno;

1508

}

1509

1510

#ifndef O_CLOEXEC

1511

/*

1512

* Based on the example in the GNU LibC manual chapter 13.13 "File

1513

* Descriptor Flags".

1514

| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |

1515

*/

1516

__attribute__((warn_unused_result))

1517

static int set_cloexec_flag(int fd){

1518

int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));

1519

/* If reading the flags failed, return error indication now. */

1520

if(ret < 0){

1521

return ret;

1522

}

1523

/* Store modified flag word in the descriptor. */

1524

return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,

1525

ret | FD_CLOEXEC));

1526

}

1527

#endif /* not O_CLOEXEC */

1528

1529

1993

__attribute__((nonnull))

1530

1994

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

1531

1995

const float delay){

1532

struct dirent **direntries;

1996

struct dirent **direntries = NULL;

1533

1997

if(hookdir_fd == -1){

1534

hookdir_fd = open(hookdir, O_RDONLY |

1535

#ifdef O_CLOEXEC

1536

O_CLOEXEC

1537

#else /* not O_CLOEXEC */

1538

0

1539

#endif /* not O_CLOEXEC */

1540

);

1998

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1999

| O_CLOEXEC);

1541

2000

if(hookdir_fd == -1){

1542

2001

if(errno == ENOENT){

1543

2002

if(debug){

1549

2008

}

1550

2009

return;

1551

2010

}

1552

#ifndef O_CLOEXEC

1553

if(set_cloexec_flag(hookdir_fd) < 0){

1554

perror_plus("set_cloexec_flag");

1555

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

1556

perror_plus("close");

1557

} else {

1558

hookdir_fd = -1;

1559

}

1560

return;

1561

}

1562

#endif /* not O_CLOEXEC */

1563

}

1564

#ifdef __GLIBC__

1565

#if __GLIBC_PREREQ(2, 15)

2011

}

2012

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

2013

if(devnull == -1){

2014

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

2015

return;

2016

}

1566

2017

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

1567

2018

runnable_hook, alphasort);

1568

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

1569

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

1570

alphasort);

1571

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

1572

#else /* not __GLIBC__ */

1573

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

1574

alphasort);

1575

#endif /* not __GLIBC__ */

1576

2019

if(numhooks == -1){

1577

2020

perror_plus("scandir");

2021

close(devnull);

1578

2022

return;

1579

2023

}

1580

2024

struct dirent *direntry;

1581

2025

int ret;

1582

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

1583

2026

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

1584

2027

direntry = direntries[i];

1585

2028

if(debug){

1590

2033

if(hook_pid == 0){

1591

2034

/* Child */

1592

2035

/* Raise privileges */

1593

if(raise_privileges_permanently() != 0){

2036

errno = raise_privileges_permanently();

2037

if(errno != 0){

1594

2038

perror_plus("Failed to raise privileges");

1595

2039

_exit(EX_NOPERM);

1596

2040

}

1608

2052

perror_plus("setgroups");

1609

2053

_exit(EX_NOPERM);

1610

2054

}

1611

ret = dup2(devnull, STDIN_FILENO);

1612

if(ret == -1){

1613

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

1614

_exit(EX_OSERR);

1615

}

1616

ret = close(devnull);

1617

if(ret == -1){

1618

perror_plus("close");

1619

_exit(EX_OSERR);

1620

}

1621

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1622

if(ret == -1){

1623

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

1624

_exit(EX_OSERR);

1625

}

1626

2055

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

1627

2056

if(ret == -1){

1628

2057

perror_plus("setenv");

1663

2092

_exit(EX_OSERR);

1664

2093

}

1665

2094

}

1666

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

1667

{ direntry->d_name, NULL }, environ) == -1){

2095

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

2096

direntry->d_name,

2097

O_RDONLY));

2098

if(hook_fd == -1){

2099

perror_plus("openat");

2100

_exit(EXIT_FAILURE);

2101

}

2102

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

2103

perror_plus("close");

2104

_exit(EXIT_FAILURE);

2105

}

2106

ret = dup2(devnull, STDIN_FILENO);

2107

if(ret == -1){

2108

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

2109

_exit(EX_OSERR);

2110

}

2111

ret = close(devnull);

2112

if(ret == -1){

2113

perror_plus("close");

2114

_exit(EX_OSERR);

2115

}

2116

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2117

if(ret == -1){

2118

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

2119

_exit(EX_OSERR);

2120

}

2121

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

2122

environ) == -1){

1668

2123

perror_plus("fexecve");

1669

2124

_exit(EXIT_FAILURE);

1670

2125

}

1671

2126

} else {

2127

if(hook_pid == -1){

2128

perror_plus("fork");

2129

free(direntry);

2130

continue;

2131

}

1672

2132

int status;

1673

2133

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

1674

2134

perror_plus("waitpid");

2135

free(direntry);

1675

2136

continue;

1676

2137

}

1677

2138

if(WIFEXITED(status)){

1679

2140

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

1680

2141

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

1681

2142

WEXITSTATUS(status));

2143

free(direntry);

1682

2144

continue;

1683

2145

}

1684

2146

} else if(WIFSIGNALED(status)){

1685

2147

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

1686

2148

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

1687

2149

WTERMSIG(status));

2150

free(direntry);

1688

2151

continue;

1689

2152

} else {

1690

2153

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

1691

2154

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

2155

free(direntry);

1692

2156

continue;

1693

2157

}

1694

2158

}

1696

2160

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

1697

2161

direntry->d_name);

1698

2162

}

2163

free(direntry);

1699

2164

}

1700

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

2165

free(direntries);

2166

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

1701

2167

perror_plus("close");

1702

2168

} else {

1703

2169

hookdir_fd = -1;

1706

2172

}

1707

2173

1708

2174

__attribute__((nonnull, warn_unused_result))

1709

error_t bring_up_interface(const char *const interface,

1710

const float delay){

1711

error_t old_errno = errno;

2175

int bring_up_interface(const char *const interface,

2176

const float delay){

2177

int old_errno = errno;

1712

2178

int ret;

1713

2179

struct ifreq network;

1714

2180

unsigned int if_index = if_nametoindex(interface);

1724

2190

}

1725

2191

1726

2192

if(not interface_is_up(interface)){

1727

error_t ret_errno = 0, ioctl_errno = 0;

2193

int ret_errno = 0;

2194

int ioctl_errno = 0;

1728

2195

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

1729

2196

ret_errno = errno;

1730

2197

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

1743

2210

}

1744

2211

1745

2212

if(quit_now){

1746

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

2213

ret = close(sd);

1747

2214

if(ret == -1){

1748

2215

perror_plus("close");

1749

2216

}

1759

2226

/* Raise privileges */

1760

2227

ret_errno = raise_privileges();

1761

2228

if(ret_errno != 0){

2229

errno = ret_errno;

1762

2230

perror_plus("Failed to raise privileges");

1763

2231

}

1764

2232

1798

2266

}

1799

2267

1800

2268

/* Close the socket */

1801

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

2269

ret = close(sd);

1802

2270

if(ret == -1){

1803

2271

perror_plus("close");

1804

2272

}

1816

2284

1817

2285

/* Sleep checking until interface is running.

1818

2286

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

1819

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

2287

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

1820

2288

if(interface_is_running(interface)){

1821

2289

break;

1822

2290

}

1832

2300

}

1833

2301

1834

2302

__attribute__((nonnull, warn_unused_result))

1835

error_t take_down_interface(const char *const interface){

1836

error_t old_errno = errno;

2303

int take_down_interface(const char *const interface){

2304

int old_errno = errno;

1837

2305

struct ifreq network;

1838

2306

unsigned int if_index = if_nametoindex(interface);

1839

2307

if(if_index == 0){

1842

2310

return ENXIO;

1843

2311

}

1844

2312

if(interface_is_up(interface)){

1845

error_t ret_errno = 0, ioctl_errno = 0;

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

1846

2315

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

1847

2316

ret_errno = errno;

1848

2317

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

1868

2337

/* Raise privileges */

1869

2338

ret_errno = raise_privileges();

1870

2339

if(ret_errno != 0){

2340

errno = ret_errno;

1871

2341

perror_plus("Failed to raise privileges");

1872

2342

}

1873

2343

1885

2355

}

1886

2356

1887

2357

/* Close the socket */

1888

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

2358

int ret = close(sd);

1889

2359

if(ret == -1){

1890

2360

perror_plus("close");

1891

2361

}

1906

2376

}

1907

2377

1908

2378

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

1909

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

1910

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

1911

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

1912

.interfaces = NULL, .interfaces_size = 0 };

2379

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

2380

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

2381

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

2382

.current_server = NULL, .interfaces = NULL,

2383

.interfaces_size = 0 };

1913

2384

AvahiSServiceBrowser *sb = NULL;

1914

2385

error_t ret_errno;

1915

2386

int ret;

1924

2395

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1925

2396

const char *seckey = PATHDIR "/" SECKEY;

1926

2397

const char *pubkey = PATHDIR "/" PUBKEY;

2398

const char *dh_params_file = NULL;

1927

2399

char *interfaces_hooks = NULL;

1928

2400

1929

2401

bool gnutls_initialized = false;

1982

2454

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

1983

2455

" Diffie-Hellman key exchange",

1984

2456

.group = 2 },

2457

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

2458

.arg = "FILE",

2459

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

2460

" for the Diffie-Hellman key exchange",

2461

.group = 2 },

1985

2462

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

1986

2463

.arg = "STRING",

1987

2464

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

2042

2519

}

2043

2520

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

2044

2521

break;

2522

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

2523

dh_params_file = arg;

2524

break;

2045

2525

case 130: /* --priority */

2046

2526

mc.priority = arg;

2047

2527

break;

2087

2567

.args_doc = "",

2088

2568

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

2089

2569

" passwords from a Mandos server" };

2090

ret = argp_parse(&argp, argc, argv,

2091

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2092

switch(ret){

2570

ret_errno = argp_parse(&argp, argc, argv,

2571

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2572

switch(ret_errno){

2093

2573

case 0:

2094

2574

break;

2095

2575

case ENOMEM:

2096

2576

default:

2097

errno = ret;

2577

errno = ret_errno;

2098

2578

perror_plus("argp_parse");

2099

2579

exitcode = EX_OSERR;

2100

2580

goto end;

2103

2583

goto end;

2104

2584

}

2105

2585

}

2106

2586

2107

2587

{

2108

2588

/* Work around Debian bug #633582:

2109

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

2589

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

2110

2590

2111

2591

/* Re-raise privileges */

2112

ret_errno = raise_privileges();

2113

if(ret_errno != 0){

2114

errno = ret_errno;

2592

ret = raise_privileges();

2593

if(ret != 0){

2594

errno = ret;

2115

2595

perror_plus("Failed to raise privileges");

2116

2596

} else {

2117

2597

struct stat st;

2133

2613

}

2134

2614

}

2135

2615

}

2136

TEMP_FAILURE_RETRY(close(seckey_fd));

2616

close(seckey_fd);

2137

2617

}

2138

2618

}

2139

2619

2140

2620

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

2141

2621

int pubkey_fd = open(pubkey, O_RDONLY);

2142

2622

if(pubkey_fd == -1){

2154

2634

}

2155

2635

}

2156

2636

}

2157

TEMP_FAILURE_RETRY(close(pubkey_fd));

2158

}

2159

}

2160

2637

close(pubkey_fd);

2638

}

2639

}

2640

2641

if(dh_params_file != NULL

2642

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

2643

int dhparams_fd = open(dh_params_file, O_RDONLY);

2644

if(dhparams_fd == -1){

2645

perror_plus("open");

2646

} else {

2647

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

2648

if(ret == -1){

2649

perror_plus("fstat");

2650

} else {

2651

if(S_ISREG(st.st_mode)

2652

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

2653

ret = fchown(dhparams_fd, uid, gid);

2654

if(ret == -1){

2655

perror_plus("fchown");

2656

}

2657

}

2658

}

2659

close(dhparams_fd);

2660

}

2661

}

2662

2161

2663

/* Lower privileges */

2162

ret_errno = lower_privileges();

2163

if(ret_errno != 0){

2164

errno = ret_errno;

2664

ret = lower_privileges();

2665

if(ret != 0){

2666

errno = ret;

2165

2667

perror_plus("Failed to lower privileges");

2166

2668

}

2167

2669

}

2280

2782

2281

2783

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

2282

2784

if(mc.interfaces == NULL){

2283

struct dirent **direntries;

2785

struct dirent **direntries = NULL;

2284

2786

/* Look for any good interfaces */

2285

2787

ret = scandir(sys_class_net, &direntries, good_interface,

2286

2788

alphasort);

2292

2794

if(ret_errno != 0){

2293

2795

errno = ret_errno;

2294

2796

perror_plus("argz_add");

2797

free(direntries[i]);

2295

2798

continue;

2296

2799

}

2297

2800

if(debug){

2298

2801

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

2299

2802

direntries[i]->d_name);

2300

2803

}

2804

free(direntries[i]);

2301

2805

}

2302

2806

free(direntries);

2303

2807

} else {

2304

free(direntries);

2808

if(ret == 0){

2809

free(direntries);

2810

}

2305

2811

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

2306

2812

exitcode = EXIT_FAILURE;

2307

2813

goto end;

2333

2839

errno = bring_up_interface(interface, delay);

2334

2840

if(not interface_was_up){

2335

2841

if(errno != 0){

2336

perror_plus("Failed to bring up interface");

2842

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

2843

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

2337

2844

} else {

2338

2845

errno = argz_add(&interfaces_to_take_down,

2339

2846

&interfaces_to_take_down_size,

2362

2869

goto end;

2363

2870

}

2364

2871

2365

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

2872

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

2366

2873

if(ret == -1){

2367

2874

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

2368

2875

exitcode = EX_UNAVAILABLE;

2490

2997

2491

2998

/* Allocate a new server */

2492

2999

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2493

&config, NULL, NULL, &ret_errno);

3000

&config, NULL, NULL, &ret);

2494

3001

2495

3002

/* Free the Avahi configuration data */

2496

3003

avahi_server_config_free(&config);

2499

3006

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

2500

3007

if(mc.server == NULL){

2501

3008

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

2502

avahi_strerror(ret_errno));

3009

avahi_strerror(ret));

2503

3010

exitcode = EX_UNAVAILABLE;

2504

3011

goto end;

2505

3012

}

2540

3047

end:

2541

3048

2542

3049

if(debug){

2543

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

3050

if(signal_received){

3051

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

3052

argv[0], signal_received,

3053

strsignal(signal_received));

3054

} else {

3055

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

3056

}

2544

3057

}

2545

3058

2546

3059

/* Cleanup things */

2557

3070

2558

3071

if(gnutls_initialized){

2559

3072

gnutls_certificate_free_credentials(mc.cred);

2560

gnutls_global_deinit();

2561

3073

gnutls_dh_params_deinit(mc.dh_params);

2562

3074

}

2563

3075

2571

3083

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

2572

3084

while(mc.current_server != NULL){

2573

3085

server *next = mc.current_server->next;

3086

#ifdef __GNUC__

3087

#pragma GCC diagnostic push

3088

#pragma GCC diagnostic ignored "-Wcast-qual"

3089

#endif

3090

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

3091

#ifdef __GNUC__

3092

#pragma GCC diagnostic pop

3093

#endif

2574

3094

free(mc.current_server);

2575

3095

mc.current_server = next;

2576

3096

}

2578

3098

2579

3099

/* Re-raise privileges */

2580

3100

{

2581

ret_errno = raise_privileges();

2582

if(ret_errno != 0){

3101

ret = raise_privileges();

3102

if(ret != 0){

3103

errno = ret;

2583

3104

perror_plus("Failed to raise privileges");

2584

3105

} else {

2585

3106

2590

3111

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

2591

3112

{

2592

3113

char *interface = NULL;

2593

while((interface=argz_next(interfaces_to_take_down,

2594

interfaces_to_take_down_size,

2595

interface))){

2596

ret_errno = take_down_interface(interface);

2597

if(ret_errno != 0){

2598

errno = ret_errno;

3114

while((interface = argz_next(interfaces_to_take_down,

3115

interfaces_to_take_down_size,

3116

interface))){

3117

ret = take_down_interface(interface);

3118

if(ret != 0){

3119

errno = ret;

2599

3120

perror_plus("Failed to take down interface");

2600

3121

}

2601

3122

}

2606

3127

}

2607

3128

}

2608

3129

2609

ret_errno = lower_privileges_permanently();

2610

if(ret_errno != 0){

3130

ret = lower_privileges_permanently();

3131

if(ret != 0){

3132

errno = ret;

2611

3133

perror_plus("Failed to lower privileges permanently");

2612

3134

}

2613

3135

}

2615

3137

free(interfaces_to_take_down);

2616

3138

free(interfaces_hooks);

2617

3139

3140

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

3141

uintmax_t level){

3142

struct dirent **direntries = NULL;

3143

int dret;

3144

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

3145

O_RDONLY

3146

| O_NOFOLLOW

3147

| O_DIRECTORY

3148

| O_PATH));

3149

if(dir_fd == -1){

3150

perror_plus("open");

3151

return;

3152

}

3153

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

3154

notdotentries, alphasort);

3155

if(numentries >= 0){

3156

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

3157

if(debug){

3158

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

3159

dirname, direntries[i]->d_name);

3160

}

3161

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

3162

if(dret == -1){

3163

if(errno == EISDIR){

3164

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

3165

AT_REMOVEDIR);

3166

}

3167

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

3168

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

3169

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

3170

/* Recurse only in this special case */

3171

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

3172

dret = 0;

3173

}

3174

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

3175

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

3176

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

3177

}

3178

}

3179

free(direntries[i]);

3180

}

3181

3182

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

3183

free(direntries);

3184

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3185

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

3186

perror_plus("rmdir");

3187

}

3188

} else {

3189

perror_plus("scandirat");

3190

}

3191

close(dir_fd);

3192

}

3193

2618

3194

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

2619

3195

if(tempdir != NULL){

2620

struct dirent **direntries = NULL;

2621

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

2622

if(tempdir_fd == -1){

2623

perror_plus("open");

2624

} else {

2625

#ifdef __GLIBC__

2626

#if __GLIBC_PREREQ(2, 15)

2627

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

2628

notdotentries, alphasort);

2629

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

2630

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

2631

alphasort);

2632

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

2633

#else /* not __GLIBC__ */

2634

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

2635

alphasort);

2636

#endif /* not __GLIBC__ */

2637

if(numentries > 0){

2638

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

2639

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

2640

if(ret == -1){

2641

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

2642

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

2643

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

2644

}

2645

}

2646

2647

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

2648

free(direntries);

2649

if(numentries == -1){

2650

perror_plus("scandir");

2651

}

2652

ret = rmdir(tempdir);

2653

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

2654

perror_plus("rmdir");

2655

}

2656

}

2657

TEMP_FAILURE_RETRY(close(tempdir_fd));

2658

}

3196

clean_dir_at(-1, tempdir, 0);

2659

3197

}

2660

3198

2661

3199

if(quit_now){