/mandos/trunk : revision 100

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

103

static const char mandos_protocol_version[] = "1";

80

const char *argp_program_version = "mandosclient 0.9";

104

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

81

105

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

82

106

83

107

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

190

214

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

191

215

gpgme_strsource(rc), gpgme_strerror(rc));

192

216

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

}

193

245

goto decrypt_end;

194

246

}

195

247

197

249

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

198

250

}

199

251

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

229

252

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

230

253

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

231

254

perror("pgpme_data_seek");

278

301

}

279

302

280

303

static const char * safer_gnutls_strerror (int value) {

281

const char *ret = gnutls_strerror (value);

304

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

282

305

if (ret == NULL)

283

306

ret = "(unknown)";

284

307

return ret;

291

314

}

292

315

293

316

static int init_gnutls_global(mandos_context *mc,

294

const char *pubkeyfile,

295

const char *seckeyfile){

317

const char *pubkeyfilename,

318

const char *seckeyfilename){

296

319

int ret;

297

320

298

321

if(debug){

299

322

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

300

323

}

301

302

if ((ret = gnutls_global_init ())

303

!= GNUTLS_E_SUCCESS) {

324

325

ret = gnutls_global_init();

326

if (ret != GNUTLS_E_SUCCESS) {

304

327

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

305

328

safer_gnutls_strerror(ret));

306

329

return -1;

315

338

}

316

339

317

340

/* OpenPGP credentials */

318

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

319

!= GNUTLS_E_SUCCESS) {

320

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

341

gnutls_certificate_allocate_credentials(&mc->cred);

342

if (ret != GNUTLS_E_SUCCESS){

343

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

344

warning */

321

345

safer_gnutls_strerror(ret));

322

346

gnutls_global_deinit ();

323

347

return -1;

325

349

326

350

if(debug){

327

351

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

328

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

329

seckeyfile);

352

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

353

seckeyfilename);

330

354

}

331

355

332

356

ret = gnutls_certificate_set_openpgp_key_file

333

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

357

(mc->cred, pubkeyfilename, seckeyfilename,

358

GNUTLS_OPENPGP_FMT_BASE64);

334

359

if (ret != GNUTLS_E_SUCCESS) {

335

360

fprintf(stderr,

336

361

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

337

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

362

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

338

363

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

339

364

safer_gnutls_strerror(ret));

340

365

goto globalfail;

360

385

361

386

globalfail:

362

387

363

gnutls_certificate_free_credentials (mc->cred);

364

gnutls_global_deinit ();

388

gnutls_certificate_free_credentials(mc->cred);

389

gnutls_global_deinit();

365

390

return -1;

366

391

367

392

}

432

457

}

433

458

434

459

if(debug){

435

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

436

ip, port);

460

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

461

"\n", ip, port);

437

462

}

438

463

439

464

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

450

475

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

451

476

}

452

477

453

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

478

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

454

479

to.in6.sin6_family = AF_INET6;

455

480

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

456

481

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

463

488

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

464

489

return -1;

465

490

}

466

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

491

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

467

492

468

493

to.in6.sin6_scope_id = (uint32_t)if_index;

469

494

470

495

if(debug){

471

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

496

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

497

port);

472

498

char addrstr[INET6_ADDRSTRLEN] = "";

473

499

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

474

500

sizeof(addrstr)) == NULL){

515

541

}

516

542

517

543

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

518

519

ret = gnutls_handshake (session);

544

545

do{

546

ret = gnutls_handshake (session);

547

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

520

548

521

549

if (ret != GNUTLS_E_SUCCESS){

522

550

if(debug){

554

582

case GNUTLS_E_AGAIN:

555

583

break;

556

584

case GNUTLS_E_REHANDSHAKE:

557

ret = gnutls_handshake (session);

585

do{

586

ret = gnutls_handshake (session);

587

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

558

588

if (ret < 0){

559

589

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

560

590

gnutls_perror (ret);

605

635

} else {

606

636

retval = -1;

607

637

}

638

} else {

639

retval = -1;

608

640

}

609

641

610

642

/* Shutdown procedure */

631

663

flags,

632

664

void* userdata) {

633

665

mandos_context *mc = userdata;

634

assert(r); /* Spurious warning */

666

assert(r);

635

667

636

668

/* Called whenever a service has been resolved successfully or

637

669

timed out */

649

681

char ip[AVAHI_ADDRESS_STR_MAX];

650

682

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

651

683

if(debug){

652

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

653

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

684

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

685

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

686

interface, port);

654

687

}

655

688

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

656

689

if (ret == 0){

657

exit(EXIT_SUCCESS);

690

avahi_simple_poll_quit(mc->simple_poll);

658

691

}

659

692

}

660

693

}

672

705

flags,

673

706

void* userdata) {

674

707

mandos_context *mc = userdata;

675

assert(b); /* Spurious warning */

708

assert(b);

676

709

677

710

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

678

711

is removed from the LAN */

714

747

715

748

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

716

749

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

717

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

718

size_t f_len = strlen(first);

719

size_t s_len = strlen(second);

720

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

721

if (tmp == NULL){

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){

722

754

return NULL;

723

755

}

724

if(f_len > 0){

725

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

726

}

727

tmp[f_len] = '/';

728

if(s_len > 0){

729

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

730

}

731

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

732

756

return tmp;

733

757

}

734

758

745

769

gid_t gid;

746

770

char *connect_to = NULL;

747

771

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

748

const char *pubkeyfile = "pubkey.txt";

749

const char *seckeyfile = "seckey.txt";

772

char *pubkeyfilename = NULL;

773

char *seckeyfilename = NULL;

774

const char *pubkeyname = "pubkey.txt";

775

const char *seckeyname = "seckey.txt";

750

776

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

751

777

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

752

778

bool gnutls_initalized = false;

804

830

keydir = arg;

805

831

break;

806

832

case 's':

807

seckeyfile = arg;

833

seckeyname = arg;

808

834

break;

809

835

case 'p':

810

pubkeyfile = arg;

836

pubkeyname = arg;

811

837

break;

812

838

case 129:

813

839

errno = 0;

822

848

break;

823

849

case ARGP_KEY_ARG:

824

850

argp_usage (state);

851

case ARGP_KEY_END:

825

852

break;

826

case ARGP_KEY_END:

827

break;

828

853

default:

829

854

return ARGP_ERR_UNKNOWN;

830

855

}

835

860

.args_doc = "",

836

861

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

837

862

" passwords from mandos server" };

838

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

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

}

839

869

}

840

870

841

pubkeyfile = combinepath(keydir, pubkeyfile);

842

if (pubkeyfile == NULL){

871

pubkeyfilename = combinepath(keydir, pubkeyname);

872

if (pubkeyfilename == NULL){

843

873

perror("combinepath");

844

874

exitcode = EXIT_FAILURE;

845

875

goto end;

846

876

}

847

877

848

seckeyfile = combinepath(keydir, seckeyfile);

849

if (seckeyfile == NULL){

878

seckeyfilename = combinepath(keydir, seckeyname);

879

if (seckeyfilename == NULL){

850

880

perror("combinepath");

881

exitcode = EXIT_FAILURE;

851

882

goto end;

852

883

}

853

884

854

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

885

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

855

886

if (ret == -1){

856

fprintf(stderr, "init_gnutls_global\n");

887

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

888

exitcode = EXIT_FAILURE;

857

889

goto end;

858

890

} else {

859

891

gnutls_initalized = true;

860

892

}

861

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

862

921

uid = getuid();

863

922

gid = getgid();

864

923

865

924

ret = setuid(uid);

866

925

if (ret == -1){

867

926

perror("setuid");

905

964

goto end;

906

965

}

907

966

908

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

909

{

910

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

911

if(sd < 0) {

912

perror("socket");

913

exitcode = EXIT_FAILURE;

914

goto end;

915

}

916

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

917

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

918

if(ret == -1){

919

perror("ioctl SIOCGIFFLAGS");

920

exitcode = EXIT_FAILURE;

921

goto end;

922

}

923

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

924

network.ifr_flags |= IFF_UP;

925

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

926

if(ret == -1){

927

perror("ioctl SIOCSIFFLAGS");

928

exitcode = EXIT_FAILURE;

929

goto end;

930

}

931

}

932

close(sd);

933

}

934

935

967

if (not debug){

936

968

avahi_set_log_function(empty_log);

937

969

}

1009

1041

1010

1042

if (mc.simple_poll != NULL)

1011

1043

avahi_simple_poll_free(mc.simple_poll);

1012

free(pubkeyfile);

1013

free(seckeyfile);

1044

free(pubkeyfilename);

1045

free(seckeyfilename);

1014

1046

1015

1047

if (gnutls_initalized){

1016

gnutls_certificate_free_credentials (mc.cred);

1048

gnutls_certificate_free_credentials(mc.cred);

1017

1049

gnutls_global_deinit ();

1018

1050

}

1019

1051