/mandos/trunk : revision 154

1

/* -*- coding: utf-8 -*- */

2

/*

3

* Mandos-client - get and decrypt data from a Mandos server

3

* Mandos client - get and decrypt data from a Mandos server

4

*

5

* This program is partly derived from an example program for an Avahi

6

* service browser, downloaded from

9

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

10

*

11

* Everything else is

12

13

12

14

13

*

15

14

* This program is free software: you can redistribute it and/or

16

15

* modify it under the terms of the GNU General Public License as

36

35

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

37

36

38

37

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

39

stdout, ferror(), sscanf(),

40

remove() */

38

stdout, ferror() */

41

39

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

42

40

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

43

41

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

49

47

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

50

48

sockaddr_in6, PF_INET6,

51

49

SOCK_STREAM, INET6_ADDRSTRLEN,

52

uid_t, gid_t, open(), opendir(),

53

DIR */

50

uid_t, gid_t, open(), opendir(), DIR */

54

51

#include <sys/stat.h> /* open() */

55

52

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

56

53

struct in6_addr, inet_pton(),

57

54

connect() */

58

55

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

59

#include <dirent.h> /* opendir(), struct dirent, readdir()

60

*/

61

#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */

56

#include <dirent.h> /* opendir(), struct dirent, readdir() */

57

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

62

58

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

63

59

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

64

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

60

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

65

61

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

66

62

SIOCSIFFLAGS, if_indextoname(),

67

63

if_nametoindex(), IF_NAMESIZE */

70

66

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

71

67

setgid() */

72

68

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

73

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

69

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

74

70

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

75

71

argp_state, struct argp,

76

72

argp_parse(), ARGP_KEY_ARG,

77

73

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

78

#include <sys/klog.h> /* klogctl() */

79

74

80

75

/* Avahi */

81

76

/* All Avahi types, constants and functions

94

89

gnutls_*

95

90

init_gnutls_session(),

96

91

GNUTLS_* */

97

#include <gnutls/openpgp.h>

98

/* gnutls_certificate_set_openpgp_key_file(),

92

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

99

93

GNUTLS_OPENPGP_FMT_BASE64 */

100

94

101

95

/* GPGME */

107

101

108

102

#define BUFFER_SIZE 256

109

103

104

/*

105

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

106

*/

107

110

108

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

111

109

#define SECKEY "seckey.txt"

112

#define PUBKEY "pubkey.txt"

110

#define PUBKEY "pupkey.txt"

113

111

114

112

bool debug = false;

115

113

static const char mandos_protocol_version[] = "1";

116

const char *argp_program_version = "mandos-client " VERSION;

114

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

117

115

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

118

116

119

117

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

134

132

*/

135

133

size_t adjustbuffer(char **buffer, size_t buffer_length,

136

134

size_t buffer_capacity){

137

if(buffer_length + BUFFER_SIZE > buffer_capacity){

135

if (buffer_length + BUFFER_SIZE > buffer_capacity){

138

136

*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

139

if(buffer == NULL){

137

if (buffer == NULL){

140

138

return 0;

141

139

}

142

140

buffer_capacity += BUFFER_SIZE;

152

150

int ret;

153

151

gpgme_error_t rc;

154

152

gpgme_engine_info_t engine_info;

155

153

156

154

157

155

/*

158

* Helper function to insert pub and seckey to the engine keyring.

156

* Helper function to insert pub and seckey to the enigne keyring.

159

157

*/

160

158

bool import_key(const char *filename){

161

159

int fd;

162

160

gpgme_data_t pgp_data;

163

161

164

fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

162

fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

165

163

if(fd == -1){

166

164

perror("open");

167

165

return false;

168

166

}

169

167

170

168

rc = gpgme_data_new_from_fd(&pgp_data, fd);

171

if(rc != GPG_ERR_NO_ERROR){

169

if (rc != GPG_ERR_NO_ERROR){

172

170

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

173

171

gpgme_strsource(rc), gpgme_strerror(rc));

174

172

return false;

175

173

}

176

174

177

175

rc = gpgme_op_import(mc->ctx, pgp_data);

178

if(rc != GPG_ERR_NO_ERROR){

176

if (rc != GPG_ERR_NO_ERROR){

179

177

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

180

178

gpgme_strsource(rc), gpgme_strerror(rc));

181

179

return false;

182

180

}

183

184

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

181

182

ret = TEMP_FAILURE_RETRY(close(fd));

185

183

if(ret == -1){

186

184

perror("close");

187

185

}

189

187

return true;

190

188

}

191

189

192

if(debug){

190

if (debug){

193

191

fprintf(stderr, "Initialize gpgme\n");

194

192

}

195

193

196

194

/* Init GPGME */

197

195

gpgme_check_version(NULL);

198

196

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

199

if(rc != GPG_ERR_NO_ERROR){

197

if (rc != GPG_ERR_NO_ERROR){

200

198

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

201

199

gpgme_strsource(rc), gpgme_strerror(rc));

202

200

return false;

203

201

}

204

202

205

203

/* Set GPGME home directory for the OpenPGP engine only */

206

rc = gpgme_get_engine_info(&engine_info);

207

if(rc != GPG_ERR_NO_ERROR){

204

rc = gpgme_get_engine_info (&engine_info);

205

if (rc != GPG_ERR_NO_ERROR){

208

206

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

209

207

gpgme_strsource(rc), gpgme_strerror(rc));

210

208

return false;

221

219

fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);

222

220

return false;

223

221

}

224

222

225

223

/* Create new GPGME "context" */

226

224

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

227

if(rc != GPG_ERR_NO_ERROR){

225

if (rc != GPG_ERR_NO_ERROR){

228

226

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

229

227

gpgme_strsource(rc), gpgme_strerror(rc));

230

228

return false;

231

229

}

232

230

233

if(not import_key(pubkey) or not import_key(seckey)){

231

if (not import_key(pubkey) or not import_key(seckey)){

234

232

return false;

235

233

}

236

234

241

239

* Decrypt OpenPGP data.

242

240

* Returns -1 on error

243

241

*/

244

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

245

const char *cryptotext,

246

size_t crypto_size,

247

char **plaintext){

242

static ssize_t pgp_packet_decrypt (const mandos_context *mc,

243

const char *cryptotext,

244

size_t crypto_size,

245

char **plaintext){

248

246

gpgme_data_t dh_crypto, dh_plain;

249

247

gpgme_error_t rc;

250

248

ssize_t ret;

251

249

size_t plaintext_capacity = 0;

252

250

ssize_t plaintext_length = 0;

253

251

254

if(debug){

252

if (debug){

255

253

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

256

254

}

257

255

258

256

/* Create new GPGME data buffer from memory cryptotext */

259

257

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

260

258

0);

261

if(rc != GPG_ERR_NO_ERROR){

259

if (rc != GPG_ERR_NO_ERROR){

262

260

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

263

261

gpgme_strsource(rc), gpgme_strerror(rc));

264

262

return -1;

266

264

267

265

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

268

266

rc = gpgme_data_new(&dh_plain);

269

if(rc != GPG_ERR_NO_ERROR){

267

if (rc != GPG_ERR_NO_ERROR){

270

268

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

271

269

gpgme_strsource(rc), gpgme_strerror(rc));

272

270

gpgme_data_release(dh_crypto);

276

274

/* Decrypt data from the cryptotext data buffer to the plaintext

277

275

data buffer */

278

276

rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);

279

if(rc != GPG_ERR_NO_ERROR){

277

if (rc != GPG_ERR_NO_ERROR){

280

278

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

281

279

gpgme_strsource(rc), gpgme_strerror(rc));

282

280

plaintext_length = -1;

283

if(debug){

281

if (debug){

284

282

gpgme_decrypt_result_t result;

285

283

result = gpgme_op_decrypt_result(mc->ctx);

286

if(result == NULL){

284

if (result == NULL){

287

285

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

288

286

} else {

289

287

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

316

314

}

317

315

318

316

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

319

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

320

perror("gpgme_data_seek");

317

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

318

perror("pgpme_data_seek");

321

319

plaintext_length = -1;

322

320

goto decrypt_end;

323

321

}

327

325

plaintext_capacity = adjustbuffer(plaintext,

328

326

(size_t)plaintext_length,

329

327

plaintext_capacity);

330

if(plaintext_capacity == 0){

328

if (plaintext_capacity == 0){

331

329

perror("adjustbuffer");

332

330

plaintext_length = -1;

333

331

goto decrypt_end;

336

334

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

337

335

BUFFER_SIZE);

338

336

/* Print the data, if any */

339

if(ret == 0){

337

if (ret == 0){

340

338

/* EOF */

341

339

break;

342

340

}

366

364

return plaintext_length;

367

365

}

368

366

369

static const char * safer_gnutls_strerror(int value) {

370

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

371

-Wunreachable-code */

372

if(ret == NULL)

367

static const char * safer_gnutls_strerror (int value) {

368

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

369

if (ret == NULL)

373

370

ret = "(unknown)";

374

371

return ret;

375

372

}

390

387

}

391

388

392

389

ret = gnutls_global_init();

393

if(ret != GNUTLS_E_SUCCESS) {

394

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

395

safer_gnutls_strerror(ret));

390

if (ret != GNUTLS_E_SUCCESS) {

391

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

392

safer_gnutls_strerror(ret));

396

393

return -1;

397

394

}

398

395

399

if(debug){

396

if (debug){

400

397

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

401

398

* - GnuTLS manual

402

399

*/

406

403

407

404

/* OpenPGP credentials */

408

405

gnutls_certificate_allocate_credentials(&mc->cred);

409

if(ret != GNUTLS_E_SUCCESS){

410

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

411

* from

412

* -Wunreachable-code

413

*/

414

safer_gnutls_strerror(ret));

415

gnutls_global_deinit();

406

if (ret != GNUTLS_E_SUCCESS){

407

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

408

warning */

409

safer_gnutls_strerror(ret));

410

gnutls_global_deinit ();

416

411

return -1;

417

412

}

418

413

425

420

ret = gnutls_certificate_set_openpgp_key_file

426

421

(mc->cred, pubkeyfilename, seckeyfilename,

427

422

GNUTLS_OPENPGP_FMT_BASE64);

428

if(ret != GNUTLS_E_SUCCESS) {

423

if (ret != GNUTLS_E_SUCCESS) {

429

424

fprintf(stderr,

430

425

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

431

426

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

436

431

437

432

/* GnuTLS server initialization */

438

433

ret = gnutls_dh_params_init(&mc->dh_params);

439

if(ret != GNUTLS_E_SUCCESS) {

440

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

441

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

434

if (ret != GNUTLS_E_SUCCESS) {

435

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

436

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

442

437

goto globalfail;

443

438

}

444

439

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

445

if(ret != GNUTLS_E_SUCCESS) {

446

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

447

safer_gnutls_strerror(ret));

440

if (ret != GNUTLS_E_SUCCESS) {

441

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

442

safer_gnutls_strerror(ret));

448

443

goto globalfail;

449

444

}

450

445

456

451

457

452

gnutls_certificate_free_credentials(mc->cred);

458

453

gnutls_global_deinit();

459

gnutls_dh_params_deinit(mc->dh_params);

460

454

return -1;

461

455

}

462

456

465

459

int ret;

466

460

/* GnuTLS session creation */

467

461

ret = gnutls_init(session, GNUTLS_SERVER);

468

if(ret != GNUTLS_E_SUCCESS){

462

if (ret != GNUTLS_E_SUCCESS){

469

463

fprintf(stderr, "Error in GnuTLS session initialization: %s\n",

470

464

safer_gnutls_strerror(ret));

471

465

}

473

467

{

474

468

const char *err;

475

469

ret = gnutls_priority_set_direct(*session, mc->priority, &err);

476

if(ret != GNUTLS_E_SUCCESS) {

470

if (ret != GNUTLS_E_SUCCESS) {

477

471

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

478

472

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

479

473

safer_gnutls_strerror(ret));

480

gnutls_deinit(*session);

474

gnutls_deinit (*session);

481

475

return -1;

482

476

}

483

477

}

484

478

485

479

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

486

480

mc->cred);

487

if(ret != GNUTLS_E_SUCCESS) {

481

if (ret != GNUTLS_E_SUCCESS) {

488

482

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

489

483

safer_gnutls_strerror(ret));

490

gnutls_deinit(*session);

484

gnutls_deinit (*session);

491

485

return -1;

492

486

}

493

487

494

488

/* ignore client certificate if any. */

495

gnutls_certificate_server_set_request(*session,

496

GNUTLS_CERT_IGNORE);

489

gnutls_certificate_server_set_request (*session,

490

GNUTLS_CERT_IGNORE);

497

491

498

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

492

gnutls_dh_set_prime_bits (*session, mc->dh_bits);

499

493

500

494

return 0;

501

495

}

509

503

AvahiIfIndex if_index,

510

504

mandos_context *mc){

511

505

int ret, tcp_sd;

512

ssize_t sret;

513

506

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

514

507

char *buffer = NULL;

515

508

char *decrypted_buffer;

521

514

char interface[IF_NAMESIZE];

522

515

gnutls_session_t session;

523

516

524

ret = init_gnutls_session(mc, &session);

525

if(ret != 0){

517

ret = init_gnutls_session (mc, &session);

518

if (ret != 0){

526

519

return -1;

527

520

}

528

521

550

543

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

551

544

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

552

545

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

553

if(ret < 0 ){

546

if (ret < 0 ){

554

547

perror("inet_pton");

555

548

return -1;

556

549

}

558

551

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

559

552

return -1;

560

553

}

561

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

562

-Wconversion and

563

-Wunreachable-code */

554

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

564

555

565

556

to.in6.sin6_scope_id = (uint32_t)if_index;

566

557

579

570

}

580

571

581

572

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

582

if(ret < 0){

573

if (ret < 0){

583

574

perror("connect");

584

575

return -1;

585

576

}

586

577

587

578

const char *out = mandos_protocol_version;

588

579

written = 0;

589

while(true){

580

while (true){

590

581

size_t out_size = strlen(out);

591

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

582

ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

592

583

out_size - written));

593

if(ret == -1){

584

if (ret == -1){

594

585

perror("write");

595

586

retval = -1;

596

587

goto mandos_end;

599

590

if(written < out_size){

600

591

continue;

601

592

} else {

602

if(out == mandos_protocol_version){

593

if (out == mandos_protocol_version){

603

594

written = 0;

604

595

out = "\r\n";

605

596

} else {

612

603

fprintf(stderr, "Establishing TLS session with %s\n", ip);

613

604

}

614

605

615

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

606

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

616

607

617

608

do{

618

ret = gnutls_handshake(session);

609

ret = gnutls_handshake (session);

619

610

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

620

611

621

if(ret != GNUTLS_E_SUCCESS){

612

if (ret != GNUTLS_E_SUCCESS){

622

613

if(debug){

623

614

fprintf(stderr, "*** GnuTLS Handshake failed ***\n");

624

gnutls_perror(ret);

615

gnutls_perror (ret);

625

616

}

626

617

retval = -1;

627

618

goto mandos_end;

637

628

while(true){

638

629

buffer_capacity = adjustbuffer(&buffer, buffer_length,

639

630

buffer_capacity);

640

if(buffer_capacity == 0){

631

if (buffer_capacity == 0){

641

632

perror("adjustbuffer");

642

633

retval = -1;

643

634

goto mandos_end;

644

635

}

645

636

646

sret = gnutls_record_recv(session, buffer+buffer_length,

647

BUFFER_SIZE);

648

if(sret == 0){

637

ret = gnutls_record_recv(session, buffer+buffer_length,

638

BUFFER_SIZE);

639

if (ret == 0){

649

640

break;

650

641

}

651

if(sret < 0){

652

switch(sret){

642

if (ret < 0){

643

switch(ret){

653

644

case GNUTLS_E_INTERRUPTED:

654

645

case GNUTLS_E_AGAIN:

655

646

break;

656

647

case GNUTLS_E_REHANDSHAKE:

657

648

do{

658

ret = gnutls_handshake(session);

649

ret = gnutls_handshake (session);

659

650

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

660

if(ret < 0){

651

if (ret < 0){

661

652

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

662

gnutls_perror(ret);

653

gnutls_perror (ret);

663

654

retval = -1;

664

655

goto mandos_end;

665

656

}

668

659

fprintf(stderr, "Unknown error while reading data from"

669

660

" encrypted session with Mandos server\n");

670

661

retval = -1;

671

gnutls_bye(session, GNUTLS_SHUT_RDWR);

662

gnutls_bye (session, GNUTLS_SHUT_RDWR);

672

663

goto mandos_end;

673

664

}

674

665

} else {

675

buffer_length += (size_t) sret;

666

buffer_length += (size_t) ret;

676

667

}

677

668

}

678

669

680

671

fprintf(stderr, "Closing TLS session\n");

681

672

}

682

673

683

gnutls_bye(session, GNUTLS_SHUT_RDWR);

674

gnutls_bye (session, GNUTLS_SHUT_RDWR);

684

675

685

if(buffer_length > 0){

676

if (buffer_length > 0){

686

677

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

687

678

buffer_length,

688

679

&decrypted_buffer);

689

if(decrypted_buffer_size >= 0){

680

if (decrypted_buffer_size >= 0){

690

681

written = 0;

691

682

while(written < (size_t) decrypted_buffer_size){

692

ret = (int)fwrite(decrypted_buffer + written, 1,

693

(size_t)decrypted_buffer_size - written,

694

stdout);

683

ret = (int)fwrite (decrypted_buffer + written, 1,

684

(size_t)decrypted_buffer_size - written,

685

stdout);

695

686

if(ret == 0 and ferror(stdout)){

696

687

if(debug){

697

688

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

714

705

715

706

mandos_end:

716

707

free(buffer);

717

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

708

ret = TEMP_FAILURE_RETRY(close(tcp_sd));

718

709

if(ret == -1){

719

710

perror("close");

720

711

}

721

gnutls_deinit(session);

712

gnutls_deinit (session);

722

713

return retval;

723

714

}

724

715

742

733

/* Called whenever a service has been resolved successfully or

743

734

timed out */

744

735

745

switch(event) {

736

switch (event) {

746

737

default:

747

738

case AVAHI_RESOLVER_FAILURE:

748

739

fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"

756

747

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

757

748

if(debug){

758

749

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

759

PRIdMAX ") on port %" PRIu16 "\n", name, host_name,

760

ip, (intmax_t)interface, port);

750

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

751

interface, port);

761

752

}

762

753

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

763

if(ret == 0){

754

if (ret == 0){

764

755

avahi_simple_poll_quit(mc->simple_poll);

765

756

}

766

757

}

784

775

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

785

776

is removed from the LAN */

786

777

787

switch(event) {

778

switch (event) {

788

779

default:

789

780

case AVAHI_BROWSER_FAILURE:

790

781

799

790

the callback function is called the Avahi server will free the

800

791

resolver for us. */

801

792

802

if(!(avahi_s_service_resolver_new(mc->server, interface,

793

if (!(avahi_s_service_resolver_new(mc->server, interface,

803

794

protocol, name, type, domain,

804

795

AVAHI_PROTO_INET6, 0,

805

796

resolve_callback, mc)))

823

814

AvahiSServiceBrowser *sb = NULL;

824

815

int error;

825

816

int ret;

826

intmax_t tmpmax;

827

int numchars;

828

817

int exitcode = EXIT_SUCCESS;

829

818

const char *interface = "eth0";

830

819

struct ifreq network;

833

822

gid_t gid;

834

823

char *connect_to = NULL;

835

824

char tempdir[] = "/tmp/mandosXXXXXX";

836

bool tempdir_created = false;

837

825

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

838

826

const char *seckey = PATHDIR "/" SECKEY;

839

827

const char *pubkey = PATHDIR "/" PUBKEY;

841

829

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

842

830

.dh_bits = 1024, .priority = "SECURE256"

843

831

":!CTYPE-X.509:+CTYPE-OPENPGP" };

844

bool gnutls_initialized = false;

845

bool gpgme_initialized = false;

846

double delay = 2.5;

832

bool gnutls_initalized = false;

833

bool pgpme_initalized = false;

847

834

848

835

{

849

836

struct argp_option options[] = {

875

862

.arg = "STRING",

876

863

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

877

864

.group = 1 },

878

{ .name = "delay", .key = 131,

879

.arg = "SECONDS",

880

.doc = "Maximum delay to wait for interface startup",

881

.group = 2 },

882

865

{ .name = NULL }

883

866

};

884

867

885

error_t parse_opt(int key, char *arg,

886

struct argp_state *state) {

887

switch(key) {

868

error_t parse_opt (int key, char *arg,

869

struct argp_state *state) {

870

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

871

a pointer to our plugin list pointer. */

872

switch (key) {

888

873

case 128: /* --debug */

889

874

debug = true;

890

875

break;

901

886

pubkey = arg;

902

887

break;

903

888

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

904

ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

905

if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax

906

or arg[numchars] != '\0'){

907

fprintf(stderr, "Bad number of DH bits\n");

889

errno = 0;

890

mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);

891

if (errno){

892

perror("strtol");

908

893

exit(EXIT_FAILURE);

909

894

}

910

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

911

895

break;

912

896

case 130: /* --priority */

913

897

mc.priority = arg;

914

898

break;

915

case 131: /* --delay */

916

ret = sscanf(arg, "%lf%n", &delay, &numchars);

917

if(ret < 1 or arg[numchars] != '\0'){

918

fprintf(stderr, "Bad delay\n");

919

exit(EXIT_FAILURE);

920

}

921

break;

922

899

case ARGP_KEY_ARG:

923

argp_usage(state);

900

argp_usage (state);

924

901

case ARGP_KEY_END:

925

902

break;

926

903

default:

933

910

.args_doc = "",

934

911

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

935

912

" passwords from a Mandos server" };

936

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

937

if(ret == ARGP_ERR_UNKNOWN){

913

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

914

if (ret == ARGP_ERR_UNKNOWN){

938

915

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

939

916

exitcode = EXIT_FAILURE;

940

917

goto end;

941

918

}

942

919

}

943

920

921

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

922

if (ret == -1){

923

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

924

exitcode = EXIT_FAILURE;

925

goto end;

926

} else {

927

gnutls_initalized = true;

928

}

929

930

if(mkdtemp(tempdir) == NULL){

931

perror("mkdtemp");

932

tempdir[0] = '\0';

933

goto end;

934

}

935

936

if(not init_gpgme(&mc, pubkey, seckey, tempdir)){

937

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

938

exitcode = EXIT_FAILURE;

939

goto end;

940

} else {

941

pgpme_initalized = true;

942

}

943

944

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

945

{

946

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

947

messages to mess up the prompt */

948

ret = klogctl(8, NULL, 5);

949

if(ret == -1){

950

perror("klogctl");

951

}

952

953

946

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

954

947

if(sd < 0) {

955

948

perror("socket");

956

949

exitcode = EXIT_FAILURE;

957

ret = klogctl(7, NULL, 0);

958

if(ret == -1){

959

perror("klogctl");

960

}

961

950

goto end;

962

951

}

963

952

strcpy(network.ifr_name, interface);

964

953

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

965

954

if(ret == -1){

966

955

perror("ioctl SIOCGIFFLAGS");

967

ret = klogctl(7, NULL, 0);

968

if(ret == -1){

969

perror("klogctl");

970

}

971

956

exitcode = EXIT_FAILURE;

972

957

goto end;

973

958

}

977

962

if(ret == -1){

978

963

perror("ioctl SIOCSIFFLAGS");

979

964

exitcode = EXIT_FAILURE;

980

ret = klogctl(7, NULL, 0);

981

if(ret == -1){

982

perror("klogctl");

983

}

984

965

goto end;

985

966

}

986

967

}

987

/* sleep checking until interface is running */

988

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

989

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

990

if(ret == -1){

991

perror("ioctl SIOCGIFFLAGS");

992

} else if(network.ifr_flags & IFF_RUNNING){

993

break;

994

}

995

struct timespec sleeptime = { .tv_nsec = 250000000 };

996

nanosleep(&sleeptime, NULL);

997

}

998

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

968

ret = TEMP_FAILURE_RETRY(close(sd));

999

969

if(ret == -1){

1000

970

perror("close");

1001

971

}

1002

/* Restores kernel loglevel to default */

1003

ret = klogctl(7, NULL, 0);

1004

if(ret == -1){

1005

perror("klogctl");

1006

}

1007

972

}

1008

973

1009

974

uid = getuid();

1010

975

gid = getgid();

1011

976

977

ret = setuid(uid);

978

if (ret == -1){

979

perror("setuid");

980

}

981

1012

982

setgid(gid);

1013

if(ret == -1){

983

if (ret == -1){

1014

984

perror("setgid");

1015

985

}

1016

986

1017

ret = setuid(uid);

1018

if(ret == -1){

1019

perror("setuid");

1020

}

1021

1022

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

1023

if(ret == -1){

1024

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

1025

exitcode = EXIT_FAILURE;

1026

goto end;

1027

} else {

1028

gnutls_initialized = true;

1029

}

1030

1031

if(mkdtemp(tempdir) == NULL){

1032

perror("mkdtemp");

1033

goto end;

1034

}

1035

tempdir_created = true;

1036

1037

if(not init_gpgme(&mc, pubkey, seckey, tempdir)){

1038

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

1039

exitcode = EXIT_FAILURE;

1040

goto end;

1041

} else {

1042

gpgme_initialized = true;

1043

}

1044

1045

987

if_index = (AvahiIfIndex) if_nametoindex(interface);

1046

988

if(if_index == 0){

1047

989

fprintf(stderr, "No such interface: \"%s\"\n", interface);

1048

exitcode = EXIT_FAILURE;

1049

goto end;

990

exit(EXIT_FAILURE);

1050

991

}

1051

992

1052

993

if(connect_to != NULL){

1058

999

exitcode = EXIT_FAILURE;

1059

1000

goto end;

1060

1001

}

1061

uint16_t port;

1062

ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);

1063

if(ret < 1 or tmpmax != (uint16_t)tmpmax

1064

or address[numchars+1] != '\0'){

1065

fprintf(stderr, "Bad port number\n");

1002

errno = 0;

1003

uint16_t port = (uint16_t) strtol(address+1, NULL, 10);

1004

if(errno){

1005

perror("Bad port number");

1066

1006

exitcode = EXIT_FAILURE;

1067

1007

goto end;

1068

1008

}

1069

port = (uint16_t)tmpmax;

1070

1009

*address = '\0';

1071

1010

address = connect_to;

1072

1011

ret = start_mandos_communication(address, port, if_index, &mc);

1078

1017

goto end;

1079

1018

}

1080

1019

1081

if(not debug){

1020

if (not debug){

1082

1021

avahi_set_log_function(empty_log);

1083

1022

}

1084

1023

1087

1026

1088

1027

/* Allocate main Avahi loop object */

1089

1028

mc.simple_poll = avahi_simple_poll_new();

1090

if(mc.simple_poll == NULL) {

1029

if (mc.simple_poll == NULL) {

1091

1030

fprintf(stderr, "Avahi: Failed to create simple poll"

1092

1031

" object.\n");

1093

1032

exitcode = EXIT_FAILURE;

1113

1052

}

1114

1053

1115

1054

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

1116

if(mc.server == NULL) {

1055

if (mc.server == NULL) {

1117

1056

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

1118

1057

avahi_strerror(error));

1119

1058

exitcode = EXIT_FAILURE;

1125

1064

AVAHI_PROTO_INET6,

1126

1065

"_mandos._tcp", NULL, 0,

1127

1066

browse_callback, &mc);

1128

if(sb == NULL) {

1067

if (sb == NULL) {

1129

1068

fprintf(stderr, "Failed to create service browser: %s\n",

1130

1069

avahi_strerror(avahi_server_errno(mc.server)));

1131

1070

exitcode = EXIT_FAILURE;

1134

1073

1135

1074

/* Run the main loop */

1136

1075

1137

if(debug){

1076

if (debug){

1138

1077

fprintf(stderr, "Starting Avahi loop search\n");

1139

1078

}

1140

1079

1141

1080

avahi_simple_poll_loop(mc.simple_poll);

1142

1081

1143

1082

end:

1144

1083

1145

if(debug){

1084

if (debug){

1146

1085

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

1147

1086

}

1148

1087

1149

1088

/* Cleanup things */

1150

if(sb != NULL)

1089

if (sb != NULL)

1151

1090

avahi_s_service_browser_free(sb);

1152

1091

1153

if(mc.server != NULL)

1092

if (mc.server != NULL)

1154

1093

avahi_server_free(mc.server);

1155

1094

1156

if(mc.simple_poll != NULL)

1095

if (mc.simple_poll != NULL)

1157

1096

avahi_simple_poll_free(mc.simple_poll);

1158

1097

1159

if(gnutls_initialized){

1098

if (gnutls_initalized){

1160

1099

gnutls_certificate_free_credentials(mc.cred);

1161

gnutls_global_deinit();

1162

gnutls_dh_params_deinit(mc.dh_params);

1100

gnutls_global_deinit ();

1163

1101

}

1164

1165

if(gpgme_initialized){

1102

1103

if(pgpme_initalized){

1166

1104

gpgme_release(mc.ctx);

1167

1105

}

1168

1106

1169

1107

/* Removes the temp directory used by GPGME */

1170

if(tempdir_created){

1108

if(tempdir[0] != '\0'){

1171

1109

DIR *d;

1172

1110

struct dirent *direntry;

1173

1111

d = opendir(tempdir);

1174

1112

if(d == NULL){

1175

if(errno != ENOENT){

1176

perror("opendir");

1177

}

1113

perror("opendir");

1178

1114

} else {

1179

1115

while(true){

1180

1116

direntry = readdir(d);

1181

1117

if(direntry == NULL){

1182

1118

break;

1183

1119

}

1184

/* Skip "." and ".." */

1185

if(direntry->d_name[0] == '.'

1186

and (direntry->d_name[1] == '\0'

1187

or (direntry->d_name[1] == '.'

1188

and direntry->d_name[2] == '\0'))){

1189

continue;

1190

}

1191

char *fullname = NULL;

1192

ret = asprintf(&fullname, "%s/%s", tempdir,

1193

direntry->d_name);

1194

if(ret < 0){

1195

perror("asprintf");

1196

continue;

1197

}

1198

ret = remove(fullname);

1199

if(ret == -1){

1200

fprintf(stderr, "remove(\"%s\"): %s\n", fullname,

1201

strerror(errno));

1202

}

1203

free(fullname);

1120

if (direntry->d_type == DT_REG){

1121

char *fullname = NULL;

1122

ret = asprintf(&fullname, "%s/%s", tempdir,

1123

direntry->d_name);

1124

if(ret < 0){

1125

perror("asprintf");

1126

continue;

1127

}

1128

ret = unlink(fullname);

1129

if(ret == -1){

1130

fprintf(stderr, "unlink(\"%s\"): %s",

1131

fullname, strerror(errno));

1132

}

1133

free(fullname);

1134

}

1204

1135

}

1205

closedir(d);

1206

1136

}

1207

1137

ret = rmdir(tempdir);

1208

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

1138

if(ret == -1){

1209

1139

perror("rmdir");

1210

1140

}

1211

1141

}

1212

1142

1213

1143

return exitcode;

1214

1144

}