/mandos/release : revision 88

32

#define _LARGEFILE_SOURCE

33

#define _FILE_OFFSET_BITS 64

34

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */

36

37

#include <stdio.h>

38

#include <assert.h>

39

#include <stdlib.h>

40

#include <time.h>

41

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

42

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

43

SIOCSIFFLAGS */

37

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

38

stdout, 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(), asprintf(), 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

85

functions:

86

gnutls_*

87

init_gnutls_session(),

88

GNUTLS_* */

89

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

90

GNUTLS_OPENPGP_FMT_BASE64 */

60

91

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,

69

struct argp_state, struct argp,

70

argp_parse() */

71

92

/* GPGME */

72

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

73

#include <gpgme.h>

93

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

94

functions:

95

gpgme_*

96

GPGME_PROTOCOL_OpenPGP,

97

GPG_ERR_NO_* */

74

98

75

99

#define BUFFER_SIZE 256

76

100

77

101

bool debug = false;

78

102

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

79

const char *argp_program_version = "mandosclient 0.9";

103

static const char mandos_protocol_version[] = "1";

104

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

80

105

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

81

static const char mandos_protocol_version[] = "1";

82

106

83

107

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

84

108

typedef struct {

90

114

const char *priority;

91

115

} mandos_context;

92

116

93

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

117

/*

118

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

94

119

* "buffer_capacity" is how much is currently allocated,

95

* "buffer_length" is how much is already used. */

120

* "buffer_length" is how much is already used.

121

*/

96

122

size_t adjustbuffer(char **buffer, size_t buffer_length,

97

123

size_t buffer_capacity){

98

124

if (buffer_length + BUFFER_SIZE > buffer_capacity){

203

229

} else {

204

230

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

205

231

result->unsupported_algorithm);

206

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

232

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

207

233

result->wrong_key_usage);

208

234

if(result->file_name != NULL){

209

235

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

276

302

}

277

303

278

304

static const char * safer_gnutls_strerror (int value) {

279

const char *ret = gnutls_strerror (value);

305

const char *ret = gnutls_strerror (value); /* Spurious warning */

280

306

if (ret == NULL)

281

307

ret = "(unknown)";

282

308

return ret;

289

315

}

290

316

291

317

static int init_gnutls_global(mandos_context *mc,

292

const char *pubkeyfile,

293

const char *seckeyfile){

318

const char *pubkeyfilename,

319

const char *seckeyfilename){

294

320

int ret;

295

321

296

322

if(debug){

297

323

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

298

324

}

299

300

if ((ret = gnutls_global_init ())

301

!= GNUTLS_E_SUCCESS) {

325

326

ret = gnutls_global_init();

327

if (ret != GNUTLS_E_SUCCESS) {

302

328

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

303

329

safer_gnutls_strerror(ret));

304

330

return -1;

313

339

}

314

340

315

341

/* OpenPGP credentials */

316

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

317

!= GNUTLS_E_SUCCESS) {

318

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

342

gnutls_certificate_allocate_credentials(&mc->cred);

343

if (ret != GNUTLS_E_SUCCESS){

344

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

345

warning */

319

346

safer_gnutls_strerror(ret));

347

gnutls_global_deinit ();

320

348

return -1;

321

349

}

322

350

323

351

if(debug){

324

352

fprintf(stderr, "Attempting to use OpenPGP certificate %s"

325

" and keyfile %s as GnuTLS credentials\n", pubkeyfile,

326

seckeyfile);

353

" and keyfile %s as GnuTLS credentials\n", pubkeyfilename,

354

seckeyfilename);

327

355

}

328

356

329

357

ret = gnutls_certificate_set_openpgp_key_file

330

(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);

358

(mc->cred, pubkeyfilename, seckeyfilename,

359

GNUTLS_OPENPGP_FMT_BASE64);

331

360

if (ret != GNUTLS_E_SUCCESS) {

332

361

fprintf(stderr,

333

362

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

334

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

363

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

335

364

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

336

365

safer_gnutls_strerror(ret));

337

return -1;

366

goto globalfail;

338

367

}

339

368

340

369

/* GnuTLS server initialization */

342

371

if (ret != GNUTLS_E_SUCCESS) {

343

372

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

344

373

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

345

return -1;

374

goto globalfail;

346

375

}

347

376

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

348

377

if (ret != GNUTLS_E_SUCCESS) {

349

378

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

350

379

safer_gnutls_strerror(ret));

351

return -1;

380

goto globalfail;

352

381

}

353

382

354

383

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

355

384

356

385

return 0;

386

387

globalfail:

388

389

gnutls_certificate_free_credentials(mc->cred);

390

gnutls_global_deinit();

391

return -1;

392

357

393

}

358

394

359

395

static int init_gnutls_session(mandos_context *mc,

373

409

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

374

410

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

375

411

safer_gnutls_strerror(ret));

412

gnutls_deinit (*session);

376

413

return -1;

377

414

}

378

415

}

382

419

if (ret != GNUTLS_E_SUCCESS) {

383

420

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

384

421

safer_gnutls_strerror(ret));

422

gnutls_deinit (*session);

385

423

return -1;

386

424

}

387

425

420

458

}

421

459

422

460

if(debug){

423

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

424

ip, port);

461

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

462

"\n", ip, port);

425

463

}

426

464

427

465

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

438

476

fprintf(stderr, "Binding to interface %s\n", interface);

439

477

}

440

478

441

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

479

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

442

480

to.in6.sin6_family = AF_INET6;

443

481

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

444

482

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

451

489

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

452

490

return -1;

453

491

}

454

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

492

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

455

493

456

494

to.in6.sin6_scope_id = (uint32_t)if_index;

457

495

458

496

if(debug){

459

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

497

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

498

port);

460

499

char addrstr[INET6_ADDRSTRLEN] = "";

461

500

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

462

501

sizeof(addrstr)) == NULL){

503

542

}

504

543

505

544

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

506

507

ret = gnutls_handshake (session);

545

546

do{

547

ret = gnutls_handshake (session);

548

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

508

549

509

550

if (ret != GNUTLS_E_SUCCESS){

510

551

if(debug){

542

583

case GNUTLS_E_AGAIN:

543

584

break;

544

585

case GNUTLS_E_REHANDSHAKE:

545

ret = gnutls_handshake (session);

586

do{

587

ret = gnutls_handshake (session);

588

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

546

589

if (ret < 0){

547

590

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

548

591

gnutls_perror (ret);

601

644

free(buffer);

602

645

close(tcp_sd);

603

646

gnutls_deinit (session);

604

gnutls_certificate_free_credentials (mc->cred);

605

gnutls_global_deinit ();

606

647

return retval;

607

648

}

608

649

621

662

flags,

622

663

void* userdata) {

623

664

mandos_context *mc = userdata;

624

assert(r); /* Spurious warning */

665

assert(r);

625

666

626

667

/* Called whenever a service has been resolved successfully or

627

668

timed out */

639

680

char ip[AVAHI_ADDRESS_STR_MAX];

640

681

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

641

682

if(debug){

642

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

643

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

683

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

684

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

685

interface, port);

644

686

}

645

687

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

646

688

if (ret == 0){

647

exit(EXIT_SUCCESS);

689

avahi_simple_poll_quit(mc->simple_poll);

648

690

}

649

691

}

650

692

}

662

704

flags,

663

705

void* userdata) {

664

706

mandos_context *mc = userdata;

665

assert(b); /* Spurious warning */

707

assert(b);

666

708

667

709

/* Called whenever a new services becomes available on the LAN or

668

710

is removed from the LAN */

704

746

705

747

/* Combines file name and path and returns the malloced new

706

748

string. some sane checks could/should be added */

707

static const char *combinepath(const char *first, const char *second){

708

size_t f_len = strlen(first);

709

size_t s_len = strlen(second);

710

char *tmp = malloc(f_len + s_len + 2);

711

if (tmp == NULL){

749

static char *combinepath(const char *first, const char *second){

750

char *tmp;

751

int ret = asprintf(&tmp, "%s/%s", first, second);

752

if(ret < 0){

712

753

return NULL;

713

754

}

714

if(f_len > 0){

715

memcpy(tmp, first, f_len); /* Spurious warning */

716

}

717

tmp[f_len] = '/';

718

if(s_len > 0){

719

memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */

720

}

721

tmp[f_len + 1 + s_len] = '\0';

722

755

return tmp;

723

756

}

724

757

735

768

gid_t gid;

736

769

char *connect_to = NULL;

737

770

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

738

const char *pubkeyfile = "pubkey.txt";

739

const char *seckeyfile = "seckey.txt";

771

char *pubkeyfilename = NULL;

772

char *seckeyfilename = NULL;

773

const char *pubkeyname = "pubkey.txt";

774

const char *seckeyname = "seckey.txt";

740

775

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

741

776

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

777

bool gnutls_initalized = false;

742

778

743

779

{

744

780

struct argp_option options[] = {

793

829

keydir = arg;

794

830

break;

795

831

case 's':

796

seckeyfile = arg;

832

seckeyname = arg;

797

833

break;

798

834

case 'p':

799

pubkeyfile = arg;

835

pubkeyname = arg;

800

836

break;

801

837

case 129:

802

838

errno = 0;

811

847

break;

812

848

case ARGP_KEY_ARG:

813

849

argp_usage (state);

850

case ARGP_KEY_END:

814

851

break;

815

case ARGP_KEY_END:

816

break;

817

852

default:

818

853

return ARGP_ERR_UNKNOWN;

819

854

}

824

859

.args_doc = "",

825

860

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

826

861

" passwords from mandos server" };

827

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

862

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

863

if (ret == ARGP_ERR_UNKNOWN){

864

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

865

exitcode = EXIT_FAILURE;

866

goto end;

867

}

828

868

}

829

869

830

pubkeyfile = combinepath(keydir, pubkeyfile);

831

if (pubkeyfile == NULL){

870

pubkeyfilename = combinepath(keydir, pubkeyname);

871

if (pubkeyfilename == NULL){

832

872

perror("combinepath");

833

873

exitcode = EXIT_FAILURE;

834

874

goto end;

835

875

}

836

876

837

seckeyfile = combinepath(keydir, seckeyfile);

838

if (seckeyfile == NULL){

877

seckeyfilename = combinepath(keydir, seckeyname);

878

if (seckeyfilename == NULL){

839

879

perror("combinepath");

880

exitcode = EXIT_FAILURE;

840

881

goto end;

841

882

}

842

883

843

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

884

ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);

844

885

if (ret == -1){

845

fprintf(stderr, "init_gnutls_global\n");

886

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

887

exitcode = EXIT_FAILURE;

846

888

goto end;

847

}

848

889

} else {

890

gnutls_initalized = true;

891

}

892

893

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

894

{

895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

896

if(sd < 0) {

897

perror("socket");

898

exitcode = EXIT_FAILURE;

899

goto end;

900

}

901

strcpy(network.ifr_name, interface);

902

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

903

if(ret == -1){

904

perror("ioctl SIOCGIFFLAGS");

905

exitcode = EXIT_FAILURE;

906

goto end;

907

}

908

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

909

network.ifr_flags |= IFF_UP;

910

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

911

if(ret == -1){

912

perror("ioctl SIOCSIFFLAGS");

913

exitcode = EXIT_FAILURE;

914

goto end;

915

}

916

}

917

close(sd);

918

}

919

849

920

uid = getuid();

850

921

gid = getgid();

851

922

852

923

ret = setuid(uid);

853

924

if (ret == -1){

854

925

perror("setuid");

892

963

goto end;

893

964

}

894

965

895

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

896

{

897

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

898

if(sd < 0) {

899

perror("socket");

900

exitcode = EXIT_FAILURE;

901

goto end;

902

}

903

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

904

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

905

if(ret == -1){

906

perror("ioctl SIOCGIFFLAGS");

907

exitcode = EXIT_FAILURE;

908

goto end;

909

}

910

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

911

network.ifr_flags |= IFF_UP;

912

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

913

if(ret == -1){

914

perror("ioctl SIOCSIFFLAGS");

915

exitcode = EXIT_FAILURE;

916

goto end;

917

}

918

}

919

close(sd);

920

}

921

922

966

if (not debug){

923

967

avahi_set_log_function(empty_log);

924

968

}

996

1040

997

1041

if (mc.simple_poll != NULL)

998

1042

avahi_simple_poll_free(mc.simple_poll);

999

free(pubkeyfile);

1000

free(seckeyfile);

1043

free(pubkeyfilename);

1044

free(seckeyfilename);

1045

1046

if (gnutls_initalized){

1047

gnutls_certificate_free_credentials(mc.cred);

1048

gnutls_global_deinit ();

1049

}

1001

1050

1002

1051

return exitcode;

1003

1052

}