/mandos/release : revision 68

34

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

36

37

#include <stdio.h>

38

#include <assert.h>

39

#include <stdlib.h>

40

#include <time.h>

41

#include <net/if.h> /* if_nametoindex */

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

43

SIOCSIFFLAGS */

37

#include <stdio.h> /* fprintf(), stderr, fwrite(), stdout,

38

ferror() */

39

#include <stdint.h> /* uint16_t, uint32_t */

40

#include <stddef.h> /* NULL, size_t, ssize_t */

41

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

42

srand() */

43

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

44

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

45

strerror(), memcpy(), strcpy() */

46

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

47

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

48

sockaddr_in6, PF_INET6,

49

SOCK_STREAM, INET6_ADDRSTRLEN,

50

uid_t, gid_t */

51

#include <inttypes.h> /* PRIu16 */

52

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

53

struct in6_addr, inet_pton(),

54

connect() */

55

#include <assert.h> /* assert() */

56

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

57

#include <time.h> /* time() */

44

58

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

45

SIOCSIFFLAGS */

59

SIOCSIFFLAGS, if_indextoname(),

60

if_nametoindex(), IF_NAMESIZE */

61

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

62

getuid(), getgid(), setuid(),

63

setgid() */

64

#include <netinet/in.h>

65

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

66

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

67

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

68

argp_state, struct argp,

69

argp_parse(), ARGP_KEY_ARG,

70

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

46

71

72

/* Avahi */

73

/* All Avahi types, constants and functions

74

Avahi*, avahi_*,

75

AVAHI_* */

47

76

#include <avahi-core/core.h>

48

77

#include <avahi-core/lookup.h>

49

78

#include <avahi-core/log.h>

51

80

#include <avahi-common/malloc.h>

52

81

#include <avahi-common/error.h>

53

82

54

/* Mandos client part */

55

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

56

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

57

struct in6_addr, inet_pton() */

58

#include <gnutls/gnutls.h> /* All GnuTLS stuff */

59

#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */

83

/* GnuTLS */

84

#include <gnutls/gnutls.h> /* All GnuTLS types, constants and functions

85

gnutls_*

86

init_gnutls_session(),

87

GNUTLS_* */

88

#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),

89

GNUTLS_OPENPGP_FMT_BASE64 */

60

90

61

#include <unistd.h> /* close() */

62

#include <netinet/in.h>

63

#include <stdbool.h> /* true */

64

#include <string.h> /* memset */

65

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

66

#include <iso646.h> /* not */

67

#include <net/if.h> /* IF_NAMESIZE */

68

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

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struct argp_state, struct argp,

70

argp_parse() */

71

91

/* GPGME */

72

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

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#include <gpgme.h>

92

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

93

gpgme_*

94

GPGME_PROTOCOL_OpenPGP,

95

GPG_ERR_NO_* */

74

96

75

97

#define BUFFER_SIZE 256

76

98

77

99

bool debug = false;

78

const char *keydir = "/conf/conf.d/mandos";

79

const char *argp_program_version = "mandosclient 0.9";

100

static const char *keydir = "/conf/conf.d/mandos";

101

static const char mandos_protocol_version[] = "1";

102

const char *argp_program_version = "password-request 1.0";

80

103

const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

81

const char mandos_protocol_version[] = "1";

82

104

83

/* Used for passing in values through all the callback functions */

105

/* Used for passing in values through the Avahi callback functions */

84

106

typedef struct {

85

107

AvahiSimplePoll *simple_poll;

86

108

AvahiServer *server;

90

112

const char *priority;

91

113

} mandos_context;

92

114

115

/*

116

* Make room in "buffer" for at least BUFFER_SIZE additional bytes.

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* "buffer_capacity" is how much is currently allocated,

118

* "buffer_length" is how much is already used.

119

*/

93

120

size_t adjustbuffer(char **buffer, size_t buffer_length,

94

121

size_t buffer_capacity){

95

122

if (buffer_length + BUFFER_SIZE > buffer_capacity){

200

227

} else {

201

228

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

202

229

result->unsupported_algorithm);

203

fprintf(stderr, "Wrong key usage: %d\n",

230

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

204

231

result->wrong_key_usage);

205

232

if(result->file_name != NULL){

206

233

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

230

257

231

258

*plaintext = NULL;

232

259

while(true){

233

plaintext_capacity = adjustbuffer(plaintext, (size_t)plaintext_length,

260

plaintext_capacity = adjustbuffer(plaintext,

261

(size_t)plaintext_length,

234

262

plaintext_capacity);

235

263

if (plaintext_capacity == 0){

236

264

perror("adjustbuffer");

292

320

if(debug){

293

321

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

294

322

}

295

296

if ((ret = gnutls_global_init ())

297

!= GNUTLS_E_SUCCESS) {

323

324

ret = gnutls_global_init();

325

if (ret != GNUTLS_E_SUCCESS) {

298

326

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

299

327

safer_gnutls_strerror(ret));

300

328

return -1;

309

337

}

310

338

311

339

/* OpenPGP credentials */

312

if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))

313

!= GNUTLS_E_SUCCESS) {

340

gnutls_certificate_allocate_credentials(&mc->cred);

341

if (ret != GNUTLS_E_SUCCESS){

314

342

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

315

343

safer_gnutls_strerror(ret));

344

gnutls_global_deinit ();

316

345

return -1;

317

346

}

318

347

330

359

" '%s')\n", ret, pubkeyfile, seckeyfile);

331

360

fprintf(stdout, "The GnuTLS error is: %s\n",

332

361

safer_gnutls_strerror(ret));

333

return -1;

362

goto globalfail;

334

363

}

335

364

336

365

/* GnuTLS server initialization */

338

367

if (ret != GNUTLS_E_SUCCESS) {

339

368

fprintf (stderr, "Error in GnuTLS DH parameter initialization:"

340

369

" %s\n", safer_gnutls_strerror(ret));

341

return -1;

370

goto globalfail;

342

371

}

343

372

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

344

373

if (ret != GNUTLS_E_SUCCESS) {

345

374

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

346

375

safer_gnutls_strerror(ret));

347

return -1;

376

goto globalfail;

348

377

}

349

378

350

379

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

351

380

352

381

return 0;

382

383

globalfail:

384

385

gnutls_certificate_free_credentials(mc->cred);

386

gnutls_global_deinit();

387

return -1;

388

353

389

}

354

390

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static int init_gnutls_session(mandos_context *mc, gnutls_session_t *session){

391

static int init_gnutls_session(mandos_context *mc,

392

gnutls_session_t *session){

356

393

int ret;

357

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/* GnuTLS session creation */

358

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ret = gnutls_init(session, GNUTLS_SERVER);

368

405

fprintf(stderr, "Syntax error at: %s\n", err);

369

406

fprintf(stderr, "GnuTLS error: %s\n",

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safer_gnutls_strerror(ret));

408

gnutls_deinit (*session);

371

409

return -1;

372

410

}

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411

}

377

415

if (ret != GNUTLS_E_SUCCESS) {

378

416

fprintf(stderr, "Error setting GnuTLS credentials: %s\n",

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safer_gnutls_strerror(ret));

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gnutls_deinit (*session);

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return -1;

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420

}

382

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398

437

AvahiIfIndex if_index,

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438

mandos_context *mc){

400

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int ret, tcp_sd;

401

struct sockaddr_in6 to;

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union { struct sockaddr in; struct sockaddr_in6 in6; } to;

402

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char *buffer = NULL;

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442

char *decrypted_buffer;

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size_t buffer_length = 0;

408

447

int retval = 0;

409

448

char interface[IF_NAMESIZE];

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449

gnutls_session_t session;

411

gnutls_dh_params_t dh_params;

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413

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ret = init_gnutls_session (mc, &session);

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if (ret != 0){

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454

}

417

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if(debug){

419

fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",

420

ip, port);

457

fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16

458

"\n", ip, port);

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459

}

422

460

423

461

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

435

473

}

436

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437

475

memset(&to,0,sizeof(to)); /* Spurious warning */

438

to.sin6_family = AF_INET6;

476

to.in6.sin6_family = AF_INET6;

439

477

/* It would be nice to have a way to detect if we were passed an

440

478

IPv4 address here. Now we assume an IPv6 address. */

441

ret = inet_pton(AF_INET6, ip, &to.sin6_addr);

479

ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);

442

480

if (ret < 0 ){

443

481

perror("inet_pton");

444

482

return -1;

447

485

fprintf(stderr, "Bad address: %s\n", ip);

448

486

return -1;

449

487

}

450

to.sin6_port = htons(port); /* Spurious warning */

488

to.in6.sin6_port = htons(port); /* Spurious warning */

451

489

452

to.sin6_scope_id = (uint32_t)if_index;

490

to.in6.sin6_scope_id = (uint32_t)if_index;

453

491

454

492

if(debug){

455

fprintf(stderr, "Connection to: %s, port %d\n", ip, port);

493

fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,

494

port);

456

495

char addrstr[INET6_ADDRSTRLEN] = "";

457

if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr,

496

if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,

458

497

sizeof(addrstr)) == NULL){

459

498

perror("inet_ntop");

460

499

} else {

464

503

}

465

504

}

466

505

467

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

506

ret = connect(tcp_sd, &to.in, sizeof(to));

468

507

if (ret < 0){

469

508

perror("connect");

470

509

return -1;

499

538

}

500

539

501

540

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

502

503

ret = gnutls_handshake (session);

541

542

do{

543

ret = gnutls_handshake (session);

544

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

504

545

505

546

if (ret != GNUTLS_E_SUCCESS){

506

547

if(debug){

519

560

}

520

561

521

562

while(true){

522

buffer_capacity = adjustbuffer(&buffer, buffer_length, buffer_capacity);

563

buffer_capacity = adjustbuffer(&buffer, buffer_length,

564

buffer_capacity);

523

565

if (buffer_capacity == 0){

524

566

perror("adjustbuffer");

525

567

retval = -1;

537

579

case GNUTLS_E_AGAIN:

538

580

break;

539

581

case GNUTLS_E_REHANDSHAKE:

540

ret = gnutls_handshake (session);

582

do{

583

ret = gnutls_handshake (session);

584

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

541

585

if (ret < 0){

542

586

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

543

587

gnutls_perror (ret);

596

640

free(buffer);

597

641

close(tcp_sd);

598

642

gnutls_deinit (session);

599

gnutls_certificate_free_credentials (mc->cred);

600

gnutls_global_deinit ();

601

643

return retval;

602

644

}

603

645

634

676

char ip[AVAHI_ADDRESS_STR_MAX];

635

677

avahi_address_snprint(ip, sizeof(ip), address);

636

678

if(debug){

637

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"

638

" port %d\n", name, host_name, ip, interface, port);

679

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"

680

PRIu16 ") on port %d\n", name, host_name, ip,

681

interface, port);

639

682

}

640

683

int ret = start_mandos_communication(ip, port, interface, mc);

641

684

if (ret == 0){

734

777

const char *seckeyfile = "seckey.txt";

735

778

mandos_context mc = { .simple_poll = NULL, .server = NULL,

736

779

.dh_bits = 1024, .priority = "SECURE256"};

780

bool gnutls_initalized = false;

737

781

738

782

{

739

783

struct argp_option options[] = {

741

785

.doc = "Debug mode", .group = 3 },

742

786

{ .name = "connect", .key = 'c',

743

787

.arg = "IP",

744

.doc = "Connect directly to a sepcified mandos server", .group = 1 },

788

.doc = "Connect directly to a sepcified mandos server",

789

.group = 1 },

745

790

{ .name = "interface", .key = 'i',

746

791

.arg = "INTERFACE",

747

.doc = "Interface that Avahi will conntect through", .group = 1 },

792

.doc = "Interface that Avahi will conntect through",

793

.group = 1 },

748

794

{ .name = "keydir", .key = 'd',

749

795

.arg = "KEYDIR",

750

.doc = "Directory where the openpgp keyring is", .group = 1 },

796

.doc = "Directory where the openpgp keyring is",

797

.group = 1 },

751

798

{ .name = "seckey", .key = 's',

752

799

.arg = "SECKEY",

753

.doc = "Secret openpgp key for gnutls authentication", .group = 1 },

800

.doc = "Secret openpgp key for gnutls authentication",

801

.group = 1 },

754

802

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

755

803

.arg = "PUBKEY",

756

.doc = "Public openpgp key for gnutls authentication", .group = 2 },

804

.doc = "Public openpgp key for gnutls authentication",

805

.group = 2 },

757

806

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

758

807

.arg = "BITS",

759

.doc = "dh-bits to use in gnutls communication", .group = 2 },

808

.doc = "dh-bits to use in gnutls communication",

809

.group = 2 },

760

810

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

761

811

.arg = "PRIORITY",

762

812

.doc = "GNUTLS priority", .group = 1 },

764

814

};

765

815

766

816

767

error_t parse_opt (int key, char *arg, struct argp_state *state) {

768

/* Get the INPUT argument from `argp_parse', which we know is a

769

pointer to our plugin list pointer. */

817

error_t parse_opt (int key, char *arg,

818

struct argp_state *state) {

819

/* Get the INPUT argument from `argp_parse', which we know is

820

a pointer to our plugin list pointer. */

770

821

switch (key) {

771

822

case 128:

772

823

debug = true;

810

861

811

862

struct argp argp = { .options = options, .parser = parse_opt,

812

863

.args_doc = "",

813

.doc = "Mandos client -- Get and decrypt passwords from mandos server" };

814

argp_parse (&argp, argc, argv, 0, 0, NULL);

864

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

865

" passwords from mandos server" };

866

ret = argp_parse (&argp, argc, argv, 0, 0, NULL);

867

if (ret == ARGP_ERR_UNKNOWN){

868

fprintf(stderr, "Unknown error while parsing arguments\n");

869

exitcode = EXIT_FAILURE;

870

goto end;

871

}

815

872

}

816

873

817

874

pubkeyfile = combinepath(keydir, pubkeyfile);

824

881

seckeyfile = combinepath(keydir, seckeyfile);

825

882

if (seckeyfile == NULL){

826

883

perror("combinepath");

884

exitcode = EXIT_FAILURE;

827

885

goto end;

828

886

}

829

887

830

888

ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);

831

889

if (ret == -1){

832

fprintf(stderr, "init_gnutls_global\n");

890

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

891

exitcode = EXIT_FAILURE;

833

892

goto end;

834

}

835

893

} else {

894

gnutls_initalized = true;

895

}

896

897

/* If the interface is down, bring it up */

898

{

899

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

900

if(sd < 0) {

901

perror("socket");

902

exitcode = EXIT_FAILURE;

903

goto end;

904

}

905

strcpy(network.ifr_name, interface); /* Spurious warning */

906

ret = ioctl(sd, SIOCGIFFLAGS, &network);

907

if(ret == -1){

908

perror("ioctl SIOCGIFFLAGS");

909

exitcode = EXIT_FAILURE;

910

goto end;

911

}

912

if((network.ifr_flags & IFF_UP) == 0){

913

network.ifr_flags |= IFF_UP;

914

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

915

if(ret == -1){

916

perror("ioctl SIOCSIFFLAGS");

917

exitcode = EXIT_FAILURE;

918

goto end;

919

}

920

}

921

close(sd);

922

}

923

836

924

uid = getuid();

837

925

gid = getgid();

838

926

839

927

ret = setuid(uid);

840

928

if (ret == -1){

841

929

perror("setuid");

879

967

goto end;

880

968

}

881

969

882

/* If the interface is down, bring it up */

883

{

884

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

885

if(sd < 0) {

886

perror("socket");

887

exitcode = EXIT_FAILURE;

888

goto end;

889

}

890

strcpy(network.ifr_name, interface); /* Spurious warning */

891

ret = ioctl(sd, SIOCGIFFLAGS, &network);

892

if(ret == -1){

893

perror("ioctl SIOCGIFFLAGS");

894

exitcode = EXIT_FAILURE;

895

goto end;

896

}

897

if((network.ifr_flags & IFF_UP) == 0){

898

network.ifr_flags |= IFF_UP;

899

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

900

if(ret == -1){

901

perror("ioctl SIOCSIFFLAGS");

902

exitcode = EXIT_FAILURE;

903

goto end;

904

}

905

}

906

close(sd);

907

}

908

909

970

if (not debug){

910

971

avahi_set_log_function(empty_log);

911

972

}

985

1046

avahi_simple_poll_free(mc.simple_poll);

986

1047

free(pubkeyfile);

987

1048

free(seckeyfile);

1049

1050

if (gnutls_initalized){

1051

gnutls_certificate_free_credentials(mc.cred);

1052

gnutls_global_deinit ();

1053

}

988

1054

989

1055

return exitcode;

990

1056

}