/mandos/trunk : revision 24.1.19

32

#define _LARGEFILE_SOURCE

33

#define _FILE_OFFSET_BITS 64

34

35

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

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

36

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() */

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 */

58

44

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

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 */

45

SIOCSIFFLAGS */

71

46

72

/* Avahi */

73

/* All Avahi types, constants and functions

74

Avahi*, avahi_*,

75

AVAHI_* */

76

47

#include <avahi-core/core.h>

77

48

#include <avahi-core/lookup.h>

78

49

#include <avahi-core/log.h>

80

51

#include <avahi-common/malloc.h>

81

52

#include <avahi-common/error.h>

82

53

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 */

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 */

91

60

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() */

92

71

/* GPGME */

93

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

94

functions:

95

gpgme_*

96

GPGME_PROTOCOL_OpenPGP,

97

GPG_ERR_NO_* */

72

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

73

#include <gpgme.h>

98

74

99

75

#define BUFFER_SIZE 256

100

76

101

77

bool debug = false;

102

78

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

103

79

static const char mandos_protocol_version[] = "1";

104

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

80

const char *argp_program_version = "mandosclient 0.9";

105

81

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

106

82

107

83

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

214

190

fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",

215

191

gpgme_strsource(rc), gpgme_strerror(rc));

216

192

plaintext_length = -1;

217

if (debug){

218

gpgme_decrypt_result_t result;

219

result = gpgme_op_decrypt_result(ctx);

220

if (result == NULL){

221

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

222

} else {

223

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

224

result->unsupported_algorithm);

225

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

226

result->wrong_key_usage);

227

if(result->file_name != NULL){

228

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

229

}

230

gpgme_recipient_t recipient;

231

recipient = result->recipients;

232

if(recipient){

233

while(recipient != NULL){

234

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

235

gpgme_pubkey_algo_name(recipient->pubkey_algo));

236

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

237

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

238

recipient->status == GPG_ERR_NO_SECKEY

239

? "No" : "Yes");

240

recipient = recipient->next;

241

}

242

}

243

}

244

}

245

193

goto decrypt_end;

246

194

}

247

195

249

197

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

250

198

}

251

199

200

if (debug){

201

gpgme_decrypt_result_t result;

202

result = gpgme_op_decrypt_result(ctx);

203

if (result == NULL){

204

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

205

} else {

206

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

207

result->unsupported_algorithm);

208

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

209

result->wrong_key_usage);

210

if(result->file_name != NULL){

211

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

212

}

213

gpgme_recipient_t recipient;

214

recipient = result->recipients;

215

if(recipient){

216

while(recipient != NULL){

217

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

218

gpgme_pubkey_algo_name(recipient->pubkey_algo));

219

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

220

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

221

recipient->status == GPG_ERR_NO_SECKEY

222

? "No" : "Yes");

223

recipient = recipient->next;

224

}

225

}

226

}

227

}

228

252

229

/* Seek back to the beginning of the GPGME plaintext data buffer */

253

230

if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){

254

231

perror("pgpme_data_seek");

301

278

}

302

279

303

280

static const char * safer_gnutls_strerror (int value) {

304

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

281

const char *ret = gnutls_strerror (value);

305

282

if (ret == NULL)

306

283

ret = "(unknown)";

307

284

return ret;

314

291

}

315

292

316

293

static int init_gnutls_global(mandos_context *mc,

317

const char *pubkeyfilename,

318

const char *seckeyfilename){

294

const char *pubkeyfile,

295

const char *seckeyfile){

319

296

int ret;

320

297

321

298

if(debug){

322

299

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

323

300

}

324

325

ret = gnutls_global_init();

326

if (ret != GNUTLS_E_SUCCESS) {

301

302

if ((ret = gnutls_global_init ())

303

!= GNUTLS_E_SUCCESS) {

327

304

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

328

305

safer_gnutls_strerror(ret));

329

306

return -1;

338

315

}

339

316

340

317

/* OpenPGP credentials */

341

gnutls_certificate_allocate_credentials(&mc->cred);

342

if (ret != GNUTLS_E_SUCCESS){

343

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

344

warning */

318

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

319

!= GNUTLS_E_SUCCESS) {

320

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

345

321

safer_gnutls_strerror(ret));

346

gnutls_global_deinit ();

347

322

return -1;

348

323

}

349

324

350

325

if(debug){

351

326

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

352

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

353

seckeyfilename);

327

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

328

seckeyfile);

354

329

}

355

330

356

331

ret = gnutls_certificate_set_openpgp_key_file

357

(mc->cred, pubkeyfilename, seckeyfilename,

358

GNUTLS_OPENPGP_FMT_BASE64);

332

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

359

333

if (ret != GNUTLS_E_SUCCESS) {

360

334

fprintf(stderr,

361

335

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

362

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

336

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

363

337

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

364

338

safer_gnutls_strerror(ret));

365

goto globalfail;

339

return -1;

366

340

}

367

341

368

342

/* GnuTLS server initialization */

370

344

if (ret != GNUTLS_E_SUCCESS) {

371

345

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

372

346

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

373

goto globalfail;

347

return -1;

374

348

}

375

349

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

376

350

if (ret != GNUTLS_E_SUCCESS) {

377

351

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

378

352

safer_gnutls_strerror(ret));

379

goto globalfail;

353

return -1;

380

354

}

381

355

382

356

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

383

357

384

358

return 0;

385

386

globalfail:

387

388

gnutls_certificate_free_credentials(mc->cred);

389

gnutls_global_deinit();

390

return -1;

391

392

359

}

393

360

394

361

static int init_gnutls_session(mandos_context *mc,

408

375

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

409

376

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

410

377

safer_gnutls_strerror(ret));

411

gnutls_deinit (*session);

412

378

return -1;

413

379

}

414

380

}

418

384

if (ret != GNUTLS_E_SUCCESS) {

419

385

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

420

386

safer_gnutls_strerror(ret));

421

gnutls_deinit (*session);

422

387

return -1;

423

388

}

424

389

457

422

}

458

423

459

424

if(debug){

460

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

461

"\n", ip, port);

425

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

426

ip, port);

462

427

}

463

428

464

429

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

475

440

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

476

441

}

477

442

478

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

443

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

479

444

to.in6.sin6_family = AF_INET6;

480

445

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

481

446

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

488

453

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

489

454

return -1;

490

455

}

491

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

456

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

492

457

493

458

to.in6.sin6_scope_id = (uint32_t)if_index;

494

459

495

460

if(debug){

496

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

497

port);

461

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

498

462

char addrstr[INET6_ADDRSTRLEN] = "";

499

463

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

500

464

sizeof(addrstr)) == NULL){

541

505

}

542

506

543

507

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

544

545

do{

546

ret = gnutls_handshake (session);

547

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

508

509

ret = gnutls_handshake (session);

548

510

549

511

if (ret != GNUTLS_E_SUCCESS){

550

512

if(debug){

582

544

case GNUTLS_E_AGAIN:

583

545

break;

584

546

case GNUTLS_E_REHANDSHAKE:

585

do{

586

ret = gnutls_handshake (session);

587

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

547

ret = gnutls_handshake (session);

588

548

if (ret < 0){

589

549

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

590

550

gnutls_perror (ret);

635

595

} else {

636

596

retval = -1;

637

597

}

638

} else {

639

retval = -1;

640

598

}

641

599

642

600

/* Shutdown procedure */

645

603

free(buffer);

646

604

close(tcp_sd);

647

605

gnutls_deinit (session);

606

gnutls_certificate_free_credentials (mc->cred);

607

gnutls_global_deinit ();

648

608

return retval;

649

609

}

650

610

663

623

flags,

664

624

void* userdata) {

665

625

mandos_context *mc = userdata;

666

assert(r);

626

assert(r); /* Spurious warning */

667

627

668

628

/* Called whenever a service has been resolved successfully or

669

629

timed out */

681

641

char ip[AVAHI_ADDRESS_STR_MAX];

682

642

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

683

643

if(debug){

684

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

685

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

686

interface, port);

644

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

645

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

687

646

}

688

647

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

689

648

if (ret == 0){

690

avahi_simple_poll_quit(mc->simple_poll);

649

exit(EXIT_SUCCESS);

691

650

}

692

651

}

693

652

}

705

664

flags,

706

665

void* userdata) {

707

666

mandos_context *mc = userdata;

708

assert(b);

667

assert(b); /* Spurious warning */

709

668

710

669

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

711

670

is removed from the LAN */

747

706

748

707

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

749

708

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

750

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

751

char *tmp;

752

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

753

if(ret < 0){

709

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

710

size_t f_len = strlen(first);

711

size_t s_len = strlen(second);

712

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

713

if (tmp == NULL){

754

714

return NULL;

755

715

}

716

if(f_len > 0){

717

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

718

}

719

tmp[f_len] = '/';

720

if(s_len > 0){

721

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

722

}

723

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

756

724

return tmp;

757

725

}

758

726

769

737

gid_t gid;

770

738

char *connect_to = NULL;

771

739

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

772

char *pubkeyfilename = NULL;

773

char *seckeyfilename = NULL;

774

const char *pubkeyname = "pubkey.txt";

775

const char *seckeyname = "seckey.txt";

740

const char *pubkeyfile = "pubkey.txt";

741

const char *seckeyfile = "seckey.txt";

776

742

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

777

743

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

778

bool gnutls_initalized = false;

779

744

780

745

{

781

746

struct argp_option options[] = {

830

795

keydir = arg;

831

796

break;

832

797

case 's':

833

seckeyname = arg;

798

seckeyfile = arg;

834

799

break;

835

800

case 'p':

836

pubkeyname = arg;

801

pubkeyfile = arg;

837

802

break;

838

803

case 129:

839

804

errno = 0;

848

813

break;

849

814

case ARGP_KEY_ARG:

850

815

argp_usage (state);

851

case ARGP_KEY_END:

852

816

break;

817

case ARGP_KEY_END:

818

break;

853

819

default:

854

820

return ARGP_ERR_UNKNOWN;

855

821

}

860

826

.args_doc = "",

861

827

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

862

828

" passwords from mandos server" };

863

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

864

if (ret == ARGP_ERR_UNKNOWN){

865

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

866

exitcode = EXIT_FAILURE;

867

goto end;

868

}

829

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

869

830

}

870

831

871

pubkeyfilename = combinepath(keydir, pubkeyname);

872

if (pubkeyfilename == NULL){

832

pubkeyfile = combinepath(keydir, pubkeyfile);

833

if (pubkeyfile == NULL){

873

834

perror("combinepath");

874

835

exitcode = EXIT_FAILURE;

875

836

goto end;

876

837

}

877

838

878

seckeyfilename = combinepath(keydir, seckeyname);

879

if (seckeyfilename == NULL){

839

seckeyfile = combinepath(keydir, seckeyfile);

840

if (seckeyfile == NULL){

880

841

perror("combinepath");

881

exitcode = EXIT_FAILURE;

882

842

goto end;

883

843

}

884

844

885

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

845

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

886

846

if (ret == -1){

887

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

888

exitcode = EXIT_FAILURE;

847

fprintf(stderr, "init_gnutls_global\n");

889

848

goto end;

890

} else {

891

gnutls_initalized = true;

892

}

893

894

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

895

{

896

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

897

if(sd < 0) {

898

perror("socket");

899

exitcode = EXIT_FAILURE;

900

goto end;

901

}

902

strcpy(network.ifr_name, interface);

903

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

904

if(ret == -1){

905

perror("ioctl SIOCGIFFLAGS");

906

exitcode = EXIT_FAILURE;

907

goto end;

908

}

909

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

910

network.ifr_flags |= IFF_UP;

911

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

912

if(ret == -1){

913

perror("ioctl SIOCSIFFLAGS");

914

exitcode = EXIT_FAILURE;

915

goto end;

916

}

917

}

918

close(sd);

919

}

920

849

}

850

921

851

uid = getuid();

922

852

gid = getgid();

923

853

924

854

ret = setuid(uid);

925

855

if (ret == -1){

926

856

perror("setuid");

964

894

goto end;

965

895

}

966

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

967

924

if (not debug){

968

925

avahi_set_log_function(empty_log);

969

926

}

1041

998

1042

999

if (mc.simple_poll != NULL)

1043

1000

avahi_simple_poll_free(mc.simple_poll);

1044

free(pubkeyfilename);

1045

free(seckeyfilename);

1046

1047

if (gnutls_initalized){

1048

gnutls_certificate_free_credentials(mc.cred);

1049

gnutls_global_deinit ();

1050

}

1001

free(pubkeyfile);

1002

free(seckeyfile);

1051

1003

1052

1004

return exitcode;

1053

1005

}