/mandos/release : revision 237.7.779

9

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

10

*

11

* Everything else is

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13

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*

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* 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.

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*

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* 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

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* (at your option) any later version.

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*

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* 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/>.

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29

*

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30

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

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31

*/

46

47

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

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48

strtof(), abort() */

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49

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

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

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

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

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asprintf(), strncpy(), strsignal()

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*/

51

53

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

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54

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

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sockaddr_in6, PF_INET6,

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59

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

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inet_pton(), connect(),

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61

getnameinfo() */

60

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

62

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

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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,

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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,

74

80

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

75

81

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

76

82

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

77

unlinkat() */

83

unlinkat(), lstat(), symlink() */

78

84

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

79

85

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

80

86

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

117

123

gnutls_*

118

124

init_gnutls_session(),

119

125

GNUTLS_* */

126

#if GNUTLS_VERSION_NUMBER < 0x030600

120

127

#include <gnutls/openpgp.h>

121

128

/* gnutls_certificate_set_openpgp_key_file(),

122

129

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

123

135

124

136

/* GPGME */

125

137

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

133

145

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

134

146

#define SECKEY "seckey.txt"

135

147

#define PUBKEY "pubkey.txt"

148

#define TLS_PRIVKEY "tls-privkey.pem"

149

#define TLS_PUBKEY "tls-pubkey.pem"

136

150

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

137

151

138

152

bool debug = false;

266

280

return true;

267

281

}

268

282

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

269

335

/*

270

336

* Initialize GPGME.

271

337

*/

291

357

return false;

292

358

}

293

359

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

if(clock_settime(CLOCK_REALTIME, &keystat.st_mtim) != 0){

400

perror_plus("clock_settime");

401

}

402

ret = lower_privileges();

403

if(ret != 0){

404

errno = ret;

405

perror_plus("Failed to lower privileges");

406

}

407

} while(false);

408

294

409

rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

410

if(rc != GPG_ERR_NO_ERROR){

296

411

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

304

419

gpgme_strsource(rc), gpgme_strerror(rc));

305

420

return false;

306

421

}

422

{

423

gpgme_import_result_t import_result

424

= gpgme_op_import_result(mc->ctx);

425

if((import_result->imported < 1

426

or import_result->not_imported > 0)

427

and import_result->unchanged == 0){

428

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

429

fprintf_plus(stderr,

430

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

431

import_result->considered);

432

fprintf_plus(stderr,

433

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

434

import_result->no_user_id);

435

fprintf_plus(stderr,

436

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

437

import_result->imported);

438

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

439

import_result->imported_rsa);

440

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

441

import_result->unchanged);

442

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

443

import_result->new_user_ids);

444

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

445

import_result->new_sub_keys);

446

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

447

import_result->new_signatures);

448

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

449

import_result->new_revocations);

450

fprintf_plus(stderr,

451

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

452

import_result->secret_read);

453

fprintf_plus(stderr,

454

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

455

import_result->secret_imported);

456

fprintf_plus(stderr,

457

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

458

import_result->secret_unchanged);

459

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

460

import_result->not_imported);

461

for(gpgme_import_status_t import_status

462

= import_result->imports;

463

import_status != NULL;

464

import_status = import_status->next){

465

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

466

import_status->fpr);

467

if(import_status->result != GPG_ERR_NO_ERROR){

468

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

469

gpgme_strsource(import_status->result),

470

gpgme_strerror(import_status->result));

471

}

472

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

473

fprintf_plus(stderr,

474

import_status->status & GPGME_IMPORT_NEW

475

? "The key was new.\n"

476

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

477

fprintf_plus(stderr,

478

import_status->status & GPGME_IMPORT_UID

479

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

480

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

481

fprintf_plus(stderr,

482

import_status->status & GPGME_IMPORT_SIG

483

? "The key contained new signatures.\n"

484

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

485

fprintf_plus(stderr,

486

import_status->status & GPGME_IMPORT_SUBKEY

487

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

488

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

489

fprintf_plus(stderr,

490

import_status->status & GPGME_IMPORT_SECRET

491

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

492

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

493

}

494

return false;

495

}

496

}

307

497

308

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

498

ret = close(fd);

309

499

if(ret == -1){

310

500

perror_plus("close");

311

501

}

350

540

/* Create new GPGME "context" */

351

541

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

352

542

if(rc != GPG_ERR_NO_ERROR){

353

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

354

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

355

gpgme_strerror(rc));

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

356

545

return false;

357

546

}

358

547

394

583

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

395

584

rc = gpgme_data_new(&dh_plain);

396

585

if(rc != GPG_ERR_NO_ERROR){

397

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

398

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

586

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

399

587

gpgme_strsource(rc), gpgme_strerror(rc));

400

588

gpgme_data_release(dh_crypto);

401

589

return -1;

414

602

if(result == NULL){

415

603

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

416

604

} else {

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);

605

if(result->unsupported_algorithm != NULL) {

606

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

607

result->unsupported_algorithm);

608

}

609

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

610

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

421

611

if(result->file_name != NULL){

422

612

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

423

613

}

424

gpgme_recipient_t recipient;

425

recipient = result->recipients;

426

while(recipient != NULL){

614

615

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

616

r = r->next){

427

617

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

618

gpgme_pubkey_algo_name(r->pubkey_algo));

619

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

431

620

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

434

recipient = recipient->next;

621

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

435

622

}

436

623

}

437

624

}

513

700

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

514

701

}

515

702

516

__attribute__((nonnull, warn_unused_result))

703

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

517

704

static int init_gnutls_global(const char *pubkeyfilename,

518

705

const char *seckeyfilename,

706

const char *dhparamsfilename,

519

707

mandos_context *mc){

520

708

int ret;

521

unsigned int uret;

522

709

523

710

if(debug){

524

711

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

525

712

}

526

713

527

ret = gnutls_global_init();

528

if(ret != GNUTLS_E_SUCCESS){

529

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

530

safer_gnutls_strerror(ret));

531

return -1;

532

}

533

534

714

if(debug){

535

715

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

536

716

* - GnuTLS manual

544

724

if(ret != GNUTLS_E_SUCCESS){

545

725

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

546

726

safer_gnutls_strerror(ret));

547

gnutls_global_deinit();

548

727

return -1;

549

728

}

550

729

551

730

if(debug){

552

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

553

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

731

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

732

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

554

733

pubkeyfilename,

555

734

seckeyfilename);

556

735

}

557

736

737

#if GNUTLS_VERSION_NUMBER >= 0x030606

738

ret = gnutls_certificate_set_rawpk_key_file

739

(mc->cred, pubkeyfilename, seckeyfilename,

740

GNUTLS_X509_FMT_PEM, /* format */

741

NULL, /* pass */

742

/* key_usage */

743

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

744

NULL, /* names */

745

0, /* names_length */

746

/* privkey_flags */

747

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

748

0); /* pkcs11_flags */

749

#elif GNUTLS_VERSION_NUMBER < 0x030600

558

750

ret = gnutls_certificate_set_openpgp_key_file

559

751

(mc->cred, pubkeyfilename, seckeyfilename,

560

752

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

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

755

#endif

561

756

if(ret != GNUTLS_E_SUCCESS){

562

757

fprintf_plus(stderr,

563

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

758

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

564

759

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

565

760

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

566

761

safer_gnutls_strerror(ret));

575

770

safer_gnutls_strerror(ret));

576

771

goto globalfail;

577

772

}

578

if(mc->dh_bits == 0){

579

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

580

/* Try to read the private key file */

581

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

582

{

583

int secfile = open(seckeyfilename, O_RDONLY);

584

size_t buffer_capacity = 0;

773

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

774

if(dhparamsfilename != NULL){

775

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

776

do {

777

int dhpfile = open(dhparamsfilename, O_RDONLY);

778

if(dhpfile == -1){

779

perror_plus("open");

780

dhparamsfilename = NULL;

781

break;

782

}

783

size_t params_capacity = 0;

585

784

while(true){

586

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

587

(size_t)buffer.size,

588

(size_t)buffer_capacity);

589

if(buffer_capacity == 0){

785

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

786

(size_t)params.size,

787

(size_t)params_capacity);

788

if(params_capacity == 0){

590

789

perror_plus("incbuffer");

591

free(buffer.data);

592

buffer.data = NULL;

790

free(params.data);

791

params.data = NULL;

792

dhparamsfilename = NULL;

593

793

break;

594

794

}

595

ssize_t bytes_read = read(secfile, buffer.data + buffer.size,

795

ssize_t bytes_read = read(dhpfile,

796

params.data + params.size,

596

797

BUFFER_SIZE);

597

798

/* EOF */

598

799

if(bytes_read == 0){

601

802

/* check bytes_read for failure */

602

803

if(bytes_read < 0){

603

804

perror_plus("read");

604

free(buffer.data);

605

buffer.data = NULL;

606

break;

607

}

608

buffer.size += (unsigned int)bytes_read;

609

}

610

close(secfile);

611

}

612

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

613

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

614

if(buffer.data != NULL){

615

{

616

gnutls_openpgp_privkey_t privkey = NULL;

617

ret = gnutls_openpgp_privkey_init(&privkey);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Error initializing OpenPGP key"

620

" structure: %s", safer_gnutls_strerror(ret));

621

free(buffer.data);

622

buffer.data = NULL;

623

} else {

624

ret = gnutls_openpgp_privkey_import(privkey, &buffer,

625

GNUTLS_OPENPGP_FMT_BASE64,

626

"", 0);

805

free(params.data);

806

params.data = NULL;

807

dhparamsfilename = NULL;

808

break;

809

}

810

params.size += (unsigned int)bytes_read;

811

}

812

ret = close(dhpfile);

813

if(ret == -1){

814

perror_plus("close");

815

}

816

if(params.data == NULL){

817

dhparamsfilename = NULL;

818

}

819

if(dhparamsfilename == NULL){

820

break;

821

}

822

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

823

GNUTLS_X509_FMT_PEM);

824

if(ret != GNUTLS_E_SUCCESS){

825

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

826

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

827

safer_gnutls_strerror(ret));

828

dhparamsfilename = NULL;

829

}

830

free(params.data);

831

} while(false);

832

}

833

if(dhparamsfilename == NULL){

834

if(mc->dh_bits == 0){

835

#if GNUTLS_VERSION_NUMBER < 0x030600

836

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

837

/* Try to read the private key file */

838

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

839

do {

840

int secfile = open(seckeyfilename, O_RDONLY);

841

if(secfile == -1){

842

perror_plus("open");

843

break;

844

}

845

size_t buffer_capacity = 0;

846

while(true){

847

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

848

(size_t)buffer.size,

849

(size_t)buffer_capacity);

850

if(buffer_capacity == 0){

851

perror_plus("incbuffer");

852

free(buffer.data);

853

buffer.data = NULL;

854

break;

855

}

856

ssize_t bytes_read = read(secfile,

857

buffer.data + buffer.size,

858

BUFFER_SIZE);

859

/* EOF */

860

if(bytes_read == 0){

861

break;

862

}

863

/* check bytes_read for failure */

864

if(bytes_read < 0){

865

perror_plus("read");

866

free(buffer.data);

867

buffer.data = NULL;

868

break;

869

}

870

buffer.size += (unsigned int)bytes_read;

871

}

872

close(secfile);

873

} while(false);

874

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

875

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

876

if(buffer.data != NULL){

877

{

878

gnutls_openpgp_privkey_t privkey = NULL;

879

ret = gnutls_openpgp_privkey_init(&privkey);

627

880

if(ret != GNUTLS_E_SUCCESS){

628

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

881

fprintf_plus(stderr, "Error initializing OpenPGP key"

882

" structure: %s",

629

883

safer_gnutls_strerror(ret));

630

privkey = NULL;

884

free(buffer.data);

885

buffer.data = NULL;

886

} else {

887

ret = gnutls_openpgp_privkey_import

888

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

889

if(ret != GNUTLS_E_SUCCESS){

890

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

891

safer_gnutls_strerror(ret));

892

privkey = NULL;

893

}

894

free(buffer.data);

895

buffer.data = NULL;

896

if(privkey != NULL){

897

/* Use private key to suggest an appropriate

898

sec_param */

899

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

900

gnutls_openpgp_privkey_deinit(privkey);

901

if(debug){

902

fprintf_plus(stderr, "This OpenPGP key implies using"

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)));

906

}

907

}

631

908

}

632

free(buffer.data);

633

buffer.data = NULL;

634

if(privkey != NULL){

635

/* Use private key to suggest an appropriate sec_param */

636

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

637

gnutls_openpgp_privkey_deinit(privkey);

638

if(debug){

639

fprintf_plus(stderr, "This OpenPGP key implies using a"

640

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

641

safe_string(gnutls_sec_param_get_name

642

(sec_param)));

643

}

909

}

910

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

911

/* Err on the side of caution */

912

sec_param = GNUTLS_SEC_PARAM_ULTRA;

913

if(debug){

914

fprintf_plus(stderr, "Falling back to security parameter"

915

" \"%s\"\n",

916

safe_string(gnutls_sec_param_get_name

917

(sec_param)));

644

918

}

645

919

}

646

920

}

647

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

648

/* Err on the side of caution */

649

sec_param = GNUTLS_SEC_PARAM_ULTRA;

921

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

922

if(uret != 0){

923

mc->dh_bits = uret;

650

924

if(debug){

651

fprintf_plus(stderr, "Falling back to security parameter"

652

" \"%s\"\n",

925

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

926

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

653

927

safe_string(gnutls_sec_param_get_name

654

(sec_param)));

928

(sec_param)),

929

mc->dh_bits);

655

930

}

656

}

657

}

658

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

659

if(uret != 0){

660

mc->dh_bits = uret;

661

if(debug){

662

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

663

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

931

} else {

932

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

933

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

664

934

safe_string(gnutls_sec_param_get_name

665

935

(sec_param)),

936

safer_gnutls_strerror(ret));

937

goto globalfail;

938

}

939

#endif

940

} else { /* dh_bits != 0 */

941

if(debug){

942

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

666

943

mc->dh_bits);

667

944

}

668

} else {

669

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

670

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

671

safe_string(gnutls_sec_param_get_name(sec_param)),

672

safer_gnutls_strerror(ret));

673

goto globalfail;

945

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

946

if(ret != GNUTLS_E_SUCCESS){

947

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

948

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

949

safer_gnutls_strerror(ret));

950

goto globalfail;

951

}

952

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

674

953

}

675

} else if(debug){

676

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

677

mc->dh_bits);

678

}

679

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

680

if(ret != GNUTLS_E_SUCCESS){

681

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

682

" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));

683

goto globalfail;

684

}

685

686

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

954

}

687

955

688

956

return 0;

689

957

690

958

globalfail:

691

959

692

960

gnutls_certificate_free_credentials(mc->cred);

693

gnutls_global_deinit();

694

961

gnutls_dh_params_deinit(mc->dh_params);

695

962

return -1;

696

963

}

701

968

int ret;

702

969

/* GnuTLS session creation */

703

970

do {

704

ret = gnutls_init(session, GNUTLS_SERVER);

971

ret = gnutls_init(session, (GNUTLS_SERVER

972

#if GNUTLS_VERSION_NUMBER >= 0x030506

973

| GNUTLS_NO_TICKETS

974

#endif

975

#if GNUTLS_VERSION_NUMBER >= 0x030606

976

| GNUTLS_ENABLE_RAWPK

977

#endif

978

));

705

979

if(quit_now){

706

980

return -1;

707

981

}

748

1022

/* ignore client certificate if any. */

749

1023

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

750

1024

751

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

752

753

1025

return 0;

754

1026

}

755

1027

757

1029

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

758

1030

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

759

1031

1032

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

1033

__attribute__((nonnull, warn_unused_result))

1034

static bool add_delete_local_route(const bool add,

1035

const char *address,

1036

AvahiIfIndex if_index){

1037

int ret;

1038

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

1039

char add_arg[] = "add";

1040

char delete_arg[] = "delete";

1041

char debug_flag[] = "--debug";

1042

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1043

if(pluginhelperdir == NULL){

1044

if(debug){

1045

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1046

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

1047

}

1048

return false;

1049

}

1050

1051

char interface[IF_NAMESIZE];

1052

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

1053

perror_plus("if_indextoname");

1054

return false;

1055

}

1056

1057

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

1058

if(devnull == -1){

1059

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

1060

return false;

1061

}

1062

pid_t pid = fork();

1063

if(pid == 0){

1064

/* Child */

1065

/* Raise privileges */

1066

errno = raise_privileges_permanently();

1067

if(errno != 0){

1068

perror_plus("Failed to raise privileges");

1069

/* _exit(EX_NOPERM); */

1070

} else {

1071

/* Set group */

1072

errno = 0;

1073

ret = setgid(0);

1074

if(ret == -1){

1075

perror_plus("setgid");

1076

close(devnull);

1077

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

close(devnull);

1085

_exit(EX_NOPERM);

1086

}

1087

}

1088

ret = dup2(devnull, STDIN_FILENO);

1089

if(ret == -1){

1090

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

1091

close(devnull);

1092

_exit(EX_OSERR);

1093

}

1094

ret = close(devnull);

1095

if(ret == -1){

1096

perror_plus("close");

1097

}

1098

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1099

if(ret == -1){

1100

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

1101

_exit(EX_OSERR);

1102

}

1103

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

1104

O_RDONLY

1105

| O_DIRECTORY

1106

| O_PATH

1107

| O_CLOEXEC));

1108

if(helperdir_fd == -1){

1109

perror_plus("open");

1110

_exit(EX_UNAVAILABLE);

1111

}

1112

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

1113

helper, O_RDONLY));

1114

if(helper_fd == -1){

1115

perror_plus("openat");

1116

close(helperdir_fd);

1117

_exit(EX_UNAVAILABLE);

1118

}

1119

close(helperdir_fd);

1120

#ifdef __GNUC__

1121

#pragma GCC diagnostic push

1122

#pragma GCC diagnostic ignored "-Wcast-qual"

1123

#endif

1124

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

1125

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

1126

interface, debug ? debug_flag : NULL, NULL },

1127

environ) == -1){

1128

#ifdef __GNUC__

1129

#pragma GCC diagnostic pop

1130

#endif

1131

perror_plus("fexecve");

1132

_exit(EXIT_FAILURE);

1133

}

1134

}

1135

if(pid == -1){

1136

perror_plus("fork");

1137

close(devnull);

1138

return false;

1139

}

1140

ret = close(devnull);

1141

if(ret == -1){

1142

perror_plus("close");

1143

}

1144

int status;

1145

pid_t pret = -1;

1146

errno = 0;

1147

do {

1148

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

1149

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

1150

int errno_raising = 0;

1151

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

1152

errno_raising = errno;

1153

perror_plus("Failed to raise privileges in order to"

1154

" kill helper program");

1155

}

1156

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

1157

perror_plus("kill");

1158

}

1159

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

1160

perror_plus("Failed to lower privileges after killing"

1161

" helper program");

1162

}

1163

return false;

1164

}

1165

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

1166

if(pret == -1){

1167

perror_plus("waitpid");

1168

return false;

1169

}

1170

if(WIFEXITED(status)){

1171

if(WEXITSTATUS(status) != 0){

1172

fprintf_plus(stderr, "Error: iprouteadddel exited"

1173

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

1174

return false;

1175

}

1176

return true;

1177

}

1178

if(WIFSIGNALED(status)){

1179

fprintf_plus(stderr, "Error: iprouteadddel died by"

1180

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

1181

return false;

1182

}

1183

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

1184

return false;

1185

}

1186

1187

__attribute__((nonnull, warn_unused_result))

1188

static bool add_local_route(const char *address,

1189

AvahiIfIndex if_index){

1190

if(debug){

1191

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

1192

}

1193

return add_delete_local_route(true, address, if_index);

1194

}

1195

1196

__attribute__((nonnull, warn_unused_result))

1197

static bool delete_local_route(const char *address,

1198

AvahiIfIndex if_index){

1199

if(debug){

1200

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

1201

}

1202

return add_delete_local_route(false, address, if_index);

1203

}

1204

760

1205

/* Called when a Mandos server is found */

761

1206

__attribute__((nonnull, warn_unused_result))

762

1207

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

773

1218

int retval = -1;

774

1219

gnutls_session_t session;

775

1220

int pf; /* Protocol family */

1221

bool route_added = false;

776

1222

777

1223

errno = 0;

778

1224

800

1246

bool match = false;

801

1247

{

802

1248

char *interface = NULL;

803

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

804

interface))){

1249

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

1250

mc->interfaces_size,

1251

interface))){

805

1252

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

806

1253

match = true;

807

1254

break;

836

1283

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

837

1284

}

838

1285

839

tcp_sd = socket(pf, SOCK_STREAM, 0);

1286

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

840

1287

if(tcp_sd < 0){

841

1288

int e = errno;

842

1289

perror_plus("socket");

849

1296

goto mandos_end;

850

1297

}

851

1298

852

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

853

1299

if(af == AF_INET6){

854

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

855

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

1300

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

1301

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

1302

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

856

1303

} else { /* IPv4 */

857

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

858

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

1304

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

1305

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

1306

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

859

1307

}

860

1308

if(ret < 0 ){

861

1309

int e = errno;

931

1379

goto mandos_end;

932

1380

}

933

1381

934

if(af == AF_INET6){

935

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

936

sizeof(struct sockaddr_in6));

937

} else {

938

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

939

sizeof(struct sockaddr_in));

940

}

941

if(ret < 0){

942

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

943

int e = errno;

944

perror_plus("connect");

945

errno = e;

946

}

947

goto mandos_end;

948

}

949

950

if(quit_now){

951

errno = EINTR;

952

goto mandos_end;

1382

while(true){

1383

if(af == AF_INET6){

1384

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

1385

sizeof(struct sockaddr_in6));

1386

} else {

1387

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

1388

sizeof(struct sockaddr_in));

1389

}

1390

if(ret < 0){

1391

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

1392

and if_index != AVAHI_IF_UNSPEC

1393

and connect_to == NULL

1394

and not route_added and

1395

((af == AF_INET6 and not

1396

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1397

&to)->sin6_addr)))

1398

or (af == AF_INET and

1399

/* Not a a IPv4LL address */

1400

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

1401

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

1402

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

1403

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

1404

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

1405

connect to a Mandos server announced by Avahi on a server

1406

host with a global address. Work around this by retrying

1407

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

1408

1409

Avahi bug reference:

1410

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

1411

https://bugs.debian.org/587961

1412

*/

1413

if(debug){

1414

fprintf_plus(stderr, "Mandos server unreachable, trying"

1415

" direct route\n");

1416

}

1417

int e = errno;

1418

route_added = add_local_route(ip, if_index);

1419

if(route_added){

1420

continue;

1421

}

1422

errno = e;

1423

}

1424

if(errno != ECONNREFUSED or debug){

1425

int e = errno;

1426

perror_plus("connect");

1427

errno = e;

1428

}

1429

goto mandos_end;

1430

}

1431

1432

if(quit_now){

1433

errno = EINTR;

1434

goto mandos_end;

1435

}

1436

break;

953

1437

}

954

1438

955

1439

const char *out = mandos_protocol_version;

1109

1593

&decrypted_buffer, mc);

1110

1594

if(decrypted_buffer_size >= 0){

1111

1595

1596

clearerr(stdout);

1112

1597

written = 0;

1113

1598

while(written < (size_t) decrypted_buffer_size){

1114

1599

if(quit_now){

1130

1615

}

1131

1616

written += (size_t)ret;

1132

1617

}

1618

ret = fflush(stdout);

1619

if(ret != 0){

1620

int e = errno;

1621

if(debug){

1622

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

1623

strerror(errno));

1624

}

1625

errno = e;

1626

goto mandos_end;

1627

}

1133

1628

retval = 0;

1134

1629

}

1135

1630

}

1138

1633

1139

1634

mandos_end:

1140

1635

{

1636

if(route_added){

1637

if(not delete_local_route(ip, if_index)){

1638

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

1639

" interface %d", ip, if_index);

1640

}

1641

}

1141

1642

int e = errno;

1142

1643

free(decrypted_buffer);

1143

1644

free(buffer);

1144

1645

if(tcp_sd >= 0){

1145

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

1646

ret = close(tcp_sd);

1146

1647

}

1147

1648

if(ret == -1){

1148

1649

if(e == 0){

1160

1661

return retval;

1161

1662

}

1162

1663

1163

__attribute__((nonnull))

1164

1664

static void resolve_callback(AvahiSServiceResolver *r,

1165

1665

AvahiIfIndex interface,

1166

1666

AvahiProtocol proto,

1303

1803

__attribute__((nonnull, warn_unused_result))

1304

1804

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

1305

1805

int ret;

1306

error_t ret_errno;

1806

int old_errno;

1307

1807

1308

1808

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

1309

1809

if(s < 0){

1310

ret_errno = errno;

1810

old_errno = errno;

1311

1811

perror_plus("socket");

1312

errno = ret_errno;

1812

errno = old_errno;

1313

1813

return false;

1314

1814

}

1315

strcpy(ifr->ifr_name, ifname);

1815

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

1816

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

1316

1817

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1317

1818

if(ret == -1){

1318

1819

if(debug){

1319

ret_errno = errno;

1820

old_errno = errno;

1320

1821

perror_plus("ioctl SIOCGIFFLAGS");

1321

errno = ret_errno;

1822

errno = old_errno;

1823

}

1824

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

1825

old_errno = errno;

1826

perror_plus("close");

1827

errno = old_errno;

1322

1828

}

1323

1829

return false;

1324

1830

}

1831

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

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1325

1836

return true;

1326

1837

}

1327

1838

1569

2080

}

1570

2081

}

1571

2082

1572

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

1573

__attribute__((warn_unused_result))

1574

error_t raise_privileges(void){

1575

error_t old_errno = errno;

1576

error_t ret_errno = 0;

1577

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

1578

ret_errno = errno;

1579

}

1580

errno = old_errno;

1581

return ret_errno;

1582

}

1583

1584

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

1585

__attribute__((warn_unused_result))

1586

error_t raise_privileges_permanently(void){

1587

error_t old_errno = errno;

1588

error_t ret_errno = raise_privileges();

1589

if(ret_errno != 0){

1590

errno = old_errno;

1591

return ret_errno;

1592

}

1593

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

1594

ret_errno = errno;

1595

}

1596

errno = old_errno;

1597

return ret_errno;

1598

}

1599

1600

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

1601

__attribute__((warn_unused_result))

1602

error_t lower_privileges(void){

1603

error_t old_errno = errno;

1604

error_t ret_errno = 0;

1605

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

1606

ret_errno = errno;

1607

}

1608

errno = old_errno;

1609

return ret_errno;

1610

}

1611

1612

/* Lower privileges permanently */

1613

__attribute__((warn_unused_result))

1614

error_t lower_privileges_permanently(void){

1615

error_t old_errno = errno;

1616

error_t ret_errno = 0;

1617

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

1618

ret_errno = errno;

1619

}

1620

errno = old_errno;

1621

return ret_errno;

1622

}

1623

1624

2083

__attribute__((nonnull))

1625

2084

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

1626

2085

const float delay){

1627

2086

struct dirent **direntries = NULL;

1628

2087

if(hookdir_fd == -1){

1629

hookdir_fd = open(hookdir, O_RDONLY);

2088

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2089

| O_CLOEXEC);

1630

2090

if(hookdir_fd == -1){

1631

2091

if(errno == ENOENT){

1632

2092

if(debug){

1639

2099

return;

1640

2100

}

1641

2101

}

1642

#ifdef __GLIBC__

1643

#if __GLIBC_PREREQ(2, 15)

2102

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

2103

if(devnull == -1){

2104

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

2105

return;

2106

}

1644

2107

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

1645

2108

runnable_hook, alphasort);

1646

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

1647

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

1648

alphasort);

1649

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

1650

#else /* not __GLIBC__ */

1651

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

1652

alphasort);

1653

#endif /* not __GLIBC__ */

1654

2109

if(numhooks == -1){

1655

2110

perror_plus("scandir");

2111

close(devnull);

1656

2112

return;

1657

2113

}

1658

2114

struct dirent *direntry;

1659

2115

int ret;

1660

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

1661

2116

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

1662

2117

direntry = direntries[i];

1663

2118

if(debug){

1687

2142

perror_plus("setgroups");

1688

2143

_exit(EX_NOPERM);

1689

2144

}

1690

ret = dup2(devnull, STDIN_FILENO);

1691

if(ret == -1){

1692

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

1693

_exit(EX_OSERR);

1694

}

1695

ret = close(devnull);

1696

if(ret == -1){

1697

perror_plus("close");

1698

_exit(EX_OSERR);

1699

}

1700

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1701

if(ret == -1){

1702

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

1703

_exit(EX_OSERR);

1704

}

1705

2145

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

1706

2146

if(ret == -1){

1707

2147

perror_plus("setenv");

1742

2182

_exit(EX_OSERR);

1743

2183

}

1744

2184

}

1745

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

2185

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

2186

direntry->d_name,

2187

O_RDONLY));

1746

2188

if(hook_fd == -1){

1747

2189

perror_plus("openat");

1748

2190

_exit(EXIT_FAILURE);

1749

2191

}

1750

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

2192

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

1751

2193

perror_plus("close");

1752

2194

_exit(EXIT_FAILURE);

1753

2195

}

2196

ret = dup2(devnull, STDIN_FILENO);

2197

if(ret == -1){

2198

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

2199

_exit(EX_OSERR);

2200

}

2201

ret = close(devnull);

2202

if(ret == -1){

2203

perror_plus("close");

2204

_exit(EX_OSERR);

2205

}

2206

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2207

if(ret == -1){

2208

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

2209

_exit(EX_OSERR);

2210

}

1754

2211

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

1755

2212

environ) == -1){

1756

2213

perror_plus("fexecve");

1796

2253

free(direntry);

1797

2254

}

1798

2255

free(direntries);

1799

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

2256

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

1800

2257

perror_plus("close");

1801

2258

} else {

1802

2259

hookdir_fd = -1;

1805

2262

}

1806

2263

1807

2264

__attribute__((nonnull, warn_unused_result))

1808

error_t bring_up_interface(const char *const interface,

1809

const float delay){

1810

error_t old_errno = errno;

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

1811

2268

int ret;

1812

2269

struct ifreq network;

1813

2270

unsigned int if_index = if_nametoindex(interface);

1823

2280

}

1824

2281

1825

2282

if(not interface_is_up(interface)){

1826

error_t ret_errno = 0, ioctl_errno = 0;

2283

int ret_errno = 0;

2284

int ioctl_errno = 0;

1827

2285

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

1828

2286

ret_errno = errno;

1829

2287

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

1842

2300

}

1843

2301

1844

2302

if(quit_now){

1845

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

2303

ret = close(sd);

1846

2304

if(ret == -1){

1847

2305

perror_plus("close");

1848

2306

}

1898

2356

}

1899

2357

1900

2358

/* Close the socket */

1901

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

2359

ret = close(sd);

1902

2360

if(ret == -1){

1903

2361

perror_plus("close");

1904

2362

}

1916

2374

1917

2375

/* Sleep checking until interface is running.

1918

2376

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

1919

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

2377

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

1920

2378

if(interface_is_running(interface)){

1921

2379

break;

1922

2380

}

1932

2390

}

1933

2391

1934

2392

__attribute__((nonnull, warn_unused_result))

1935

error_t take_down_interface(const char *const interface){

1936

error_t old_errno = errno;

2393

int take_down_interface(const char *const interface){

2394

int old_errno = errno;

1937

2395

struct ifreq network;

1938

2396

unsigned int if_index = if_nametoindex(interface);

1939

2397

if(if_index == 0){

1942

2400

return ENXIO;

1943

2401

}

1944

2402

if(interface_is_up(interface)){

1945

error_t ret_errno = 0, ioctl_errno = 0;

2403

int ret_errno = 0;

2404

int ioctl_errno = 0;

1946

2405

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

1947

2406

ret_errno = errno;

1948

2407

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

1986

2445

}

1987

2446

1988

2447

/* Close the socket */

1989

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

2448

int ret = close(sd);

1990

2449

if(ret == -1){

1991

2450

perror_plus("close");

1992

2451

}

2008

2467

2009

2468

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

2010

2469

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

2011

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

2012

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

2013

.interfaces = NULL, .interfaces_size = 0 };

2470

#if GNUTLS_VERSION_NUMBER >= 0x030606

2471

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

2472

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

2473

":%PROFILE_ULTRA",

2474

#elif GNUTLS_VERSION_NUMBER < 0x030600

2475

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

2476

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

2477

#else

2478

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

2479

#endif

2480

.current_server = NULL, .interfaces = NULL,

2481

.interfaces_size = 0 };

2014

2482

AvahiSServiceBrowser *sb = NULL;

2015

2483

error_t ret_errno;

2016

2484

int ret;

2025

2493

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2026

2494

const char *seckey = PATHDIR "/" SECKEY;

2027

2495

const char *pubkey = PATHDIR "/" PUBKEY;

2496

#if GNUTLS_VERSION_NUMBER >= 0x030606

2497

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2498

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2499

#endif

2500

const char *dh_params_file = NULL;

2028

2501

char *interfaces_hooks = NULL;

2029

2502

2030

2503

bool gnutls_initialized = false;

2077

2550

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

2078

2551

.arg = "FILE",

2079

2552

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

2080

.group = 2 },

2553

.group = 1 },

2554

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

2555

.arg = "FILE",

2556

#if GNUTLS_VERSION_NUMBER >= 0x030606

2557

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

2558

#else

2559

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

2560

#endif

2561

.group = 1 },

2562

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

2563

.arg = "FILE",

2564

#if GNUTLS_VERSION_NUMBER >= 0x030606

2565

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

2566

#else

2567

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

2568

#endif

2569

.group = 1 },

2081

2570

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

2082

2571

.arg = "BITS",

2083

2572

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

2084

2573

" Diffie-Hellman key exchange",

2085

2574

.group = 2 },

2575

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

2576

.arg = "FILE",

2577

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

2578

" for the Diffie-Hellman key exchange",

2579

.group = 2 },

2086

2580

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

2087

2581

.arg = "STRING",

2088

2582

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

2134

2628

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

2135

2629

pubkey = arg;

2136

2630

break;

2631

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

2632

#if GNUTLS_VERSION_NUMBER >= 0x030606

2633

tls_privkey = arg;

2634

#endif

2635

break;

2636

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

2637

#if GNUTLS_VERSION_NUMBER >= 0x030606

2638

tls_pubkey = arg;

2639

#endif

2640

break;

2137

2641

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

2138

2642

errno = 0;

2139

2643

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

2143

2647

}

2144

2648

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

2145

2649

break;

2650

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

2651

dh_params_file = arg;

2652

break;

2146

2653

case 130: /* --priority */

2147

2654

mc.priority = arg;

2148

2655

break;

2171

2678

argp_state_help(state, state->out_stream,

2172

2679

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2173

2680

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

2174

2682

case -3: /* --usage */

2175

2683

argp_state_help(state, state->out_stream,

2176

2684

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

2177

2686

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

2178

2687

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

2179

2688

exit(argp_err_exit_status);

2188

2697

.args_doc = "",

2189

2698

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

2190

2699

" passwords from a Mandos server" };

2191

ret = argp_parse(&argp, argc, argv,

2192

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2193

switch(ret){

2700

ret_errno = argp_parse(&argp, argc, argv,

2701

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2702

switch(ret_errno){

2194

2703

case 0:

2195

2704

break;

2196

2705

case ENOMEM:

2197

2706

default:

2198

errno = ret;

2707

errno = ret_errno;

2199

2708

perror_plus("argp_parse");

2200

2709

exitcode = EX_OSERR;

2201

2710

goto end;

2204

2713

goto end;

2205

2714

}

2206

2715

}

2207

2716

2208

2717

{

2209

/* Work around Debian bug #633582:

2210

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

2211

2212

2718

/* Re-raise privileges */

2213

ret_errno = raise_privileges();

2214

if(ret_errno != 0){

2215

errno = ret_errno;

2719

ret = raise_privileges();

2720

if(ret != 0){

2721

errno = ret;

2216

2722

perror_plus("Failed to raise privileges");

2217

2723

} else {

2218

2724

struct stat st;

2219

2725

2726

/* Work around Debian bug #633582:

2727

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

2728

2220

2729

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

2221

2730

int seckey_fd = open(seckey, O_RDONLY);

2222

2731

if(seckey_fd == -1){

2234

2743

}

2235

2744

}

2236

2745

}

2237

TEMP_FAILURE_RETRY(close(seckey_fd));

2746

close(seckey_fd);

2238

2747

}

2239

2748

}

2240

2749

2241

2750

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

2242

2751

int pubkey_fd = open(pubkey, O_RDONLY);

2243

2752

if(pubkey_fd == -1){

2255

2764

}

2256

2765

}

2257

2766

}

2258

TEMP_FAILURE_RETRY(close(pubkey_fd));

2259

}

2260

}

2261

2767

close(pubkey_fd);

2768

}

2769

}

2770

2771

if(dh_params_file != NULL

2772

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

2773

int dhparams_fd = open(dh_params_file, O_RDONLY);

2774

if(dhparams_fd == -1){

2775

perror_plus("open");

2776

} else {

2777

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

2778

if(ret == -1){

2779

perror_plus("fstat");

2780

} else {

2781

if(S_ISREG(st.st_mode)

2782

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

2783

ret = fchown(dhparams_fd, uid, gid);

2784

if(ret == -1){

2785

perror_plus("fchown");

2786

}

2787

}

2788

}

2789

close(dhparams_fd);

2790

}

2791

}

2792

2793

/* Work around Debian bug #981302

2794

<https://bugs.debian.org/981302> */

2795

if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){

2796

ret = symlink("/proc/self/fd", "/dev/fd");

2797

if(ret == -1){

2798

perror_plus("Failed to create /dev/fd symlink");

2799

}

2800

}

2801

2262

2802

/* Lower privileges */

2263

ret_errno = lower_privileges();

2264

if(ret_errno != 0){

2265

errno = ret_errno;

2803

ret = lower_privileges();

2804

if(ret != 0){

2805

errno = ret;

2266

2806

perror_plus("Failed to lower privileges");

2267

2807

}

2268

2808

}

2438

2978

errno = bring_up_interface(interface, delay);

2439

2979

if(not interface_was_up){

2440

2980

if(errno != 0){

2441

perror_plus("Failed to bring up interface");

2981

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

2982

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

2442

2983

} else {

2443

2984

errno = argz_add(&interfaces_to_take_down,

2444

2985

&interfaces_to_take_down_size,

2467

3008

goto end;

2468

3009

}

2469

3010

2470

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

3011

#if GNUTLS_VERSION_NUMBER >= 0x030606

3012

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

3013

#elif GNUTLS_VERSION_NUMBER < 0x030600

3014

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

3015

#else

3016

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

3017

#endif

2471

3018

if(ret == -1){

2472

3019

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

2473

3020

exitcode = EX_UNAVAILABLE;

2595

3142

2596

3143

/* Allocate a new server */

2597

3144

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2598

&config, NULL, NULL, &ret_errno);

3145

&config, NULL, NULL, &ret);

2599

3146

2600

3147

/* Free the Avahi configuration data */

2601

3148

avahi_server_config_free(&config);

2604

3151

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

2605

3152

if(mc.server == NULL){

2606

3153

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

2607

avahi_strerror(ret_errno));

3154

avahi_strerror(ret));

2608

3155

exitcode = EX_UNAVAILABLE;

2609

3156

goto end;

2610

3157

}

2645

3192

end:

2646

3193

2647

3194

if(debug){

2648

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

3195

if(signal_received){

3196

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

3197

argv[0], signal_received,

3198

strsignal(signal_received));

3199

} else {

3200

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

3201

}

2649

3202

}

2650

3203

2651

3204

/* Cleanup things */

2662

3215

2663

3216

if(gnutls_initialized){

2664

3217

gnutls_certificate_free_credentials(mc.cred);

2665

gnutls_global_deinit();

2666

3218

gnutls_dh_params_deinit(mc.dh_params);

2667

3219

}

2668

3220

2691

3243

2692

3244

/* Re-raise privileges */

2693

3245

{

2694

ret_errno = raise_privileges();

2695

if(ret_errno != 0){

2696

errno = ret_errno;

3246

ret = raise_privileges();

3247

if(ret != 0){

3248

errno = ret;

2697

3249

perror_plus("Failed to raise privileges");

2698

3250

} else {

2699

3251

2704

3256

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

2705

3257

{

2706

3258

char *interface = NULL;

2707

while((interface=argz_next(interfaces_to_take_down,

2708

interfaces_to_take_down_size,

2709

interface))){

2710

ret_errno = take_down_interface(interface);

2711

if(ret_errno != 0){

2712

errno = ret_errno;

3259

while((interface = argz_next(interfaces_to_take_down,

3260

interfaces_to_take_down_size,

3261

interface))){

3262

ret = take_down_interface(interface);

3263

if(ret != 0){

3264

errno = ret;

2713

3265

perror_plus("Failed to take down interface");

2714

3266

}

2715

3267

}

2720

3272

}

2721

3273

}

2722

3274

2723

ret_errno = lower_privileges_permanently();

2724

if(ret_errno != 0){

2725

errno = ret_errno;

3275

ret = lower_privileges_permanently();

3276

if(ret != 0){

3277

errno = ret;

2726

3278

perror_plus("Failed to lower privileges permanently");

2727

3279

}

2728

3280

}

2730

3282

free(interfaces_to_take_down);

2731

3283

free(interfaces_hooks);

2732

3284

3285

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

3286

uintmax_t level){

3287

struct dirent **direntries = NULL;

3288

int dret;

3289

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

3290

O_RDONLY

3291

| O_NOFOLLOW

3292

| O_DIRECTORY

3293

| O_PATH));

3294

if(dir_fd == -1){

3295

perror_plus("open");

3296

return;

3297

}

3298

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

3299

notdotentries, alphasort);

3300

if(numentries >= 0){

3301

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

3302

if(debug){

3303

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

3304

dirname, direntries[i]->d_name);

3305

}

3306

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

3307

if(dret == -1){

3308

if(errno == EISDIR){

3309

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

3310

AT_REMOVEDIR);

3311

}

3312

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

3313

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

3314

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

3315

/* Recurse only in this special case */

3316

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

3317

dret = 0;

3318

}

3319

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

3320

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

3321

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

3322

}

3323

}

3324

free(direntries[i]);

3325

}

3326

3327

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

3328

free(direntries);

3329

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3330

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

3331

perror_plus("rmdir");

3332

}

3333

} else {

3334

perror_plus("scandirat");

3335

}

3336

close(dir_fd);

3337

}

3338

2733

3339

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

2734

3340

if(tempdir != NULL){

2735

struct dirent **direntries = NULL;

2736

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

2737

O_NOFOLLOW));

2738

if(tempdir_fd == -1){

2739

perror_plus("open");

2740

} else {

2741

#ifdef __GLIBC__

2742

#if __GLIBC_PREREQ(2, 15)

2743

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

2744

notdotentries, alphasort);

2745

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

2746

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

2747

alphasort);

2748

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

2749

#else /* not __GLIBC__ */

2750

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

2751

alphasort);

2752

#endif /* not __GLIBC__ */

2753

if(numentries >= 0){

2754

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

2755

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

2756

if(ret == -1){

2757

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

2758

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

2759

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

2760

}

2761

free(direntries[i]);

2762

}

2763

2764

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

2765

free(direntries);

2766

if(numentries == -1){

2767

perror_plus("scandir");

2768

}

2769

ret = rmdir(tempdir);

2770

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

2771

perror_plus("rmdir");

2772

}

2773

}

2774

TEMP_FAILURE_RETRY(close(tempdir_fd));

2775

}

3341

clean_dir_at(-1, tempdir, 0);

2776

3342

}

2777

3343

2778

3344

if(quit_now){