/mandos/release : revision 24.1.173

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

30

*/

31

32

/* Needed by GPGME, specifically gpgme_data_seek() */

33

#ifndef _LARGEFILE_SOURCE

33

34

#define _LARGEFILE_SOURCE

35

#endif

36

#ifndef _FILE_OFFSET_BITS

34

37

#define _FILE_OFFSET_BITS 64

38

#endif

35

39

36

40

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

37

41

38

42

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

39

stdout, ferror(), sscanf(),

40

remove() */

43

stdout, ferror(), remove() */

41

44

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

42

45

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

43

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

44

srand() */

45

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

46

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

47

strtof(), abort() */

48

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

46

49

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

47

50

strerror(), asprintf(), strcpy() */

48

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

51

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

49

52

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

50

53

sockaddr_in6, PF_INET6,

51

SOCK_STREAM, INET6_ADDRSTRLEN,

52

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

53

DIR */

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

54

56

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

55

57

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

56

struct in6_addr, inet_pton(),

57

connect() */

58

inet_pton(), connect() */

58

59

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

59

60

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

60

61

*/

61

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

62

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

63

strtoimax() */

62

64

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

63

65

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

64

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

66

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

65

67

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

66

68

SIOCSIFFLAGS, if_indextoname(),

67

69

if_nametoindex(), IF_NAMESIZE */

68

#include <netinet/in.h>

70

#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,

71

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

72

*/

69

73

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

70

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

71

setgid() */

74

getuid(), getgid(), seteuid(),

75

setgid(), pause() */

72

76

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

73

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

77

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

74

78

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

75

79

argp_state, struct argp,

76

80

argp_parse(), ARGP_KEY_ARG,

77

81

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

82

#include <signal.h> /* sigemptyset(), sigaddset(),

83

sigaction(), SIGTERM, sig_atomic_t,

84

raise() */

85

#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

86

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

87

78

88

#ifdef __linux__

79

89

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

80

#endif

90

#endif /* __linux__ */

81

91

82

92

/* Avahi */

83

93

/* All Avahi types, constants and functions

117

127

static const char mandos_protocol_version[] = "1";

118

128

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

119

129

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

130

static const char sys_class_net[] = "/sys/class/net";

131

char *connect_to = NULL;

120

132

121

133

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

122

134

typedef struct {

129

141

gpgme_ctx_t ctx;

130

142

} mandos_context;

131

143

144

/* global context so signal handler can reach it*/

145

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

146

.dh_bits = 1024, .priority = "SECURE256"

147

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

148

149

sig_atomic_t quit_now = 0;

150

int signal_received = 0;

151

132

152

/*

133

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

134

* "buffer_capacity" is how much is currently allocated,

153

* Make additional room in "buffer" for at least BUFFER_SIZE more

154

* bytes. "buffer_capacity" is how much is currently allocated,

135

155

* "buffer_length" is how much is already used.

136

156

*/

137

size_t adjustbuffer(char **buffer, size_t buffer_length,

157

size_t incbuffer(char **buffer, size_t buffer_length,

138

158

size_t buffer_capacity){

139

159

if(buffer_length + BUFFER_SIZE > buffer_capacity){

140

160

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

149

169

/*

150

170

* Initialize GPGME.

151

171

*/

152

static bool init_gpgme(mandos_context *mc, const char *seckey,

172

static bool init_gpgme(const char *seckey,

153

173

const char *pubkey, const char *tempdir){

154

int ret;

155

174

gpgme_error_t rc;

156

175

gpgme_engine_info_t engine_info;

157

176

160

179

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

161

180

*/

162

181

bool import_key(const char *filename){

182

int ret;

163

183

int fd;

164

184

gpgme_data_t pgp_data;

165

185

176

196

return false;

177

197

}

178

198

179

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

199

rc = gpgme_op_import(mc.ctx, pgp_data);

180

200

if(rc != GPG_ERR_NO_ERROR){

181

201

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

182

202

gpgme_strsource(rc), gpgme_strerror(rc));

192

212

}

193

213

194

214

if(debug){

195

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

215

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

196

216

}

197

217

198

218

/* Init GPGME */

225

245

}

226

246

227

247

/* Create new GPGME "context" */

228

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

248

rc = gpgme_new(&(mc.ctx));

229

249

if(rc != GPG_ERR_NO_ERROR){

230

250

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

231

251

gpgme_strsource(rc), gpgme_strerror(rc));

236

256

return false;

237

257

}

238

258

239

return true;

259

return true;

240

260

}

241

261

242

262

/*

243

263

* Decrypt OpenPGP data.

244

264

* Returns -1 on error

245

265

*/

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

266

static ssize_t pgp_packet_decrypt(const char *cryptotext,

248

267

size_t crypto_size,

249

268

char **plaintext){

250

269

gpgme_data_t dh_crypto, dh_plain;

277

296

278

297

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

279

298

data buffer */

280

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

299

rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);

281

300

if(rc != GPG_ERR_NO_ERROR){

282

301

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

283

302

gpgme_strsource(rc), gpgme_strerror(rc));

284

303

plaintext_length = -1;

285

304

if(debug){

286

305

gpgme_decrypt_result_t result;

287

result = gpgme_op_decrypt_result(mc->ctx);

306

result = gpgme_op_decrypt_result(mc.ctx);

288

307

if(result == NULL){

289

308

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

290

309

} else {

297

316

}

298

317

gpgme_recipient_t recipient;

299

318

recipient = result->recipients;

300

if(recipient){

301

while(recipient != NULL){

302

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

303

gpgme_pubkey_algo_name(recipient->pubkey_algo));

304

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

305

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

306

recipient->status == GPG_ERR_NO_SECKEY

307

? "No" : "Yes");

308

recipient = recipient->next;

309

}

319

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

326

recipient = recipient->next;

310

327

}

311

328

}

312

329

}

326

343

327

344

*plaintext = NULL;

328

345

while(true){

329

plaintext_capacity = adjustbuffer(plaintext,

346

plaintext_capacity = incbuffer(plaintext,

330

347

(size_t)plaintext_length,

331

348

plaintext_capacity);

332

349

if(plaintext_capacity == 0){

333

perror("adjustbuffer");

350

perror("incbuffer");

334

351

plaintext_length = -1;

335

352

goto decrypt_end;

336

353

}

382

399

fprintf(stderr, "GnuTLS: %s", string);

383

400

}

384

401

385

static int init_gnutls_global(mandos_context *mc,

386

const char *pubkeyfilename,

402

static int init_gnutls_global(const char *pubkeyfilename,

387

403

const char *seckeyfilename){

388

404

int ret;

389

405

407

423

}

408

424

409

425

/* OpenPGP credentials */

410

gnutls_certificate_allocate_credentials(&mc->cred);

426

gnutls_certificate_allocate_credentials(&mc.cred);

411

427

if(ret != GNUTLS_E_SUCCESS){

412

428

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

413

* from

414

* -Wunreachable-code

415

*/

429

from

430

-Wunreachable-code

431

*/

416

432

safer_gnutls_strerror(ret));

417

433

gnutls_global_deinit();

418

434

return -1;

425

441

}

426

442

427

443

ret = gnutls_certificate_set_openpgp_key_file

428

(mc->cred, pubkeyfilename, seckeyfilename,

444

(mc.cred, pubkeyfilename, seckeyfilename,

429

445

GNUTLS_OPENPGP_FMT_BASE64);

430

446

if(ret != GNUTLS_E_SUCCESS){

431

447

fprintf(stderr,

437

453

}

438

454

439

455

/* GnuTLS server initialization */

440

ret = gnutls_dh_params_init(&mc->dh_params);

456

ret = gnutls_dh_params_init(&mc.dh_params);

441

457

if(ret != GNUTLS_E_SUCCESS){

442

458

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

443

459

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

444

460

goto globalfail;

445

461

}

446

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

462

ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);

447

463

if(ret != GNUTLS_E_SUCCESS){

448

464

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

449

465

safer_gnutls_strerror(ret));

450

466

goto globalfail;

451

467

}

452

468

453

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

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

454

470

455

471

return 0;

456

472

457

473

globalfail:

458

474

459

gnutls_certificate_free_credentials(mc->cred);

475

gnutls_certificate_free_credentials(mc.cred);

460

476

gnutls_global_deinit();

461

gnutls_dh_params_deinit(mc->dh_params);

477

gnutls_dh_params_deinit(mc.dh_params);

462

478

return -1;

463

479

}

464

480

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

481

static int init_gnutls_session(gnutls_session_t *session){

467

482

int ret;

468

483

/* GnuTLS session creation */

469

ret = gnutls_init(session, GNUTLS_SERVER);

484

do {

485

ret = gnutls_init(session, GNUTLS_SERVER);

486

if(quit_now){

487

return -1;

488

}

489

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

470

490

if(ret != GNUTLS_E_SUCCESS){

471

491

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

472

492

safer_gnutls_strerror(ret));

474

494

475

495

{

476

496

const char *err;

477

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

497

do {

498

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

499

if(quit_now){

500

gnutls_deinit(*session);

501

return -1;

502

}

503

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

478

504

if(ret != GNUTLS_E_SUCCESS){

479

505

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

480

506

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

484

510

}

485

511

}

486

512

487

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

513

do {

514

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

516

if(quit_now){

517

gnutls_deinit(*session);

518

return -1;

519

}

520

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

489

521

if(ret != GNUTLS_E_SUCCESS){

490

522

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

491

523

safer_gnutls_strerror(ret));

494

526

}

495

527

496

528

/* ignore client certificate if any. */

497

gnutls_certificate_server_set_request(*session,

498

GNUTLS_CERT_IGNORE);

529

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

499

530

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

501

532

502

533

return 0;

503

534

}

509

540

/* Called when a Mandos server is found */

510

541

static int start_mandos_communication(const char *ip, uint16_t port,

511

542

AvahiIfIndex if_index,

512

mandos_context *mc){

513

int ret, tcp_sd;

543

int af){

544

int ret, tcp_sd = -1;

514

545

ssize_t sret;

515

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

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

516

550

char *buffer = NULL;

517

char *decrypted_buffer;

551

char *decrypted_buffer = NULL;

518

552

size_t buffer_length = 0;

519

553

size_t buffer_capacity = 0;

520

ssize_t decrypted_buffer_size;

521

554

size_t written;

522

int retval = 0;

523

char interface[IF_NAMESIZE];

555

int retval = -1;

524

556

gnutls_session_t session;

525

526

ret = init_gnutls_session(mc, &session);

557

int pf; /* Protocol family */

558

559

errno = 0;

560

561

if(quit_now){

562

errno = EINTR;

563

return -1;

564

}

565

566

switch(af){

567

case AF_INET6:

568

pf = PF_INET6;

569

break;

570

case AF_INET:

571

pf = PF_INET;

572

break;

573

default:

574

fprintf(stderr, "Bad address family: %d\n", af);

575

errno = EINVAL;

576

return -1;

577

}

578

579

ret = init_gnutls_session(&session);

527

580

if(ret != 0){

528

581

return -1;

529

582

}

530

583

531

584

if(debug){

532

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

585

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

533

586

"\n", ip, port);

534

587

}

535

588

536

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

537

590

if(tcp_sd < 0){

591

int e = errno;

538

592

perror("socket");

539

return -1;

593

errno = e;

594

goto mandos_end;

540

595

}

541

596

542

if(debug){

543

if(if_indextoname((unsigned int)if_index, interface) == NULL){

544

perror("if_indextoname");

545

return -1;

546

}

547

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

597

if(quit_now){

598

errno = EINTR;

599

goto mandos_end;

548

600

}

549

601

550

602

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

551

to.in6.sin6_family = AF_INET6;

552

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

553

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

554

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

603

if(af == AF_INET6){

604

to.in6.sin6_family = (sa_family_t)af;

605

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

606

} else { /* IPv4 */

607

to.in.sin_family = (sa_family_t)af;

608

ret = inet_pton(af, ip, &to.in.sin_addr);

609

}

555

610

if(ret < 0 ){

611

int e = errno;

556

612

perror("inet_pton");

557

return -1;

613

errno = e;

614

goto mandos_end;

558

615

}

559

616

if(ret == 0){

617

int e = errno;

560

618

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

561

return -1;

619

errno = e;

620

goto mandos_end;

562

621

}

563

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

622

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and

629

-Wunreachable-code*/

630

if(if_index == AVAHI_IF_UNSPEC){

631

fprintf(stderr, "An IPv6 link-local address is incomplete"

632

" without a network interface\n");

633

errno = EINVAL;

634

goto mandos_end;

635

}

636

/* Set the network interface number as scope */

637

to.in6.sin6_scope_id = (uint32_t)if_index;

638

}

639

} else {

640

to.in.sin_port = htons(port); /* Spurious warnings from

564

641

-Wconversion and

565

642

-Wunreachable-code */

643

}

566

644

567

to.in6.sin6_scope_id = (uint32_t)if_index;

645

if(quit_now){

646

errno = EINTR;

647

goto mandos_end;

648

}

568

649

569

650

if(debug){

570

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

571

port);

572

char addrstr[INET6_ADDRSTRLEN] = "";

573

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

574

sizeof(addrstr)) == NULL){

651

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

652

char interface[IF_NAMESIZE];

653

if(if_indextoname((unsigned int)if_index, interface) == NULL){

654

perror("if_indextoname");

655

} else {

656

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

657

ip, interface, port);

658

}

659

} else {

660

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

661

port);

662

}

663

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

665

const char *pcret;

666

if(af == AF_INET6){

667

pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,

668

sizeof(addrstr));

669

} else {

670

pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,

671

sizeof(addrstr));

672

}

673

if(pcret == NULL){

575

674

perror("inet_ntop");

576

675

} else {

577

676

if(strcmp(addrstr, ip) != 0){

580

679

}

581

680

}

582

681

583

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

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

687

if(af == AF_INET6){

688

ret = connect(tcp_sd, &to.in6, sizeof(to));

689

} else {

690

ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */

691

}

584

692

if(ret < 0){

585

perror("connect");

586

return -1;

693

if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){

694

int e = errno;

695

perror("connect");

696

errno = e;

697

}

698

goto mandos_end;

699

}

700

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

587

704

}

588

705

589

706

const char *out = mandos_protocol_version;

593

710

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

594

711

out_size - written));

595

712

if(ret == -1){

713

int e = errno;

596

714

perror("write");

597

retval = -1;

715

errno = e;

598

716

goto mandos_end;

599

717

}

600

718

written += (size_t)ret;

608

726

break;

609

727

}

610

728

}

729

730

if(quit_now){

731

errno = EINTR;

732

goto mandos_end;

733

}

611

734

}

612

735

613

736

if(debug){

614

737

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

615

738

}

616

739

740

if(quit_now){

741

errno = EINTR;

742

goto mandos_end;

743

}

744

745

/* Spurious warnings from -Wint-to-pointer-cast */

617

746

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

618

747

619

do{

748

if(quit_now){

749

errno = EINTR;

750

goto mandos_end;

751

}

752

753

do {

620

754

ret = gnutls_handshake(session);

755

if(quit_now){

756

errno = EINTR;

757

goto mandos_end;

758

}

621

759

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

622

760

623

761

if(ret != GNUTLS_E_SUCCESS){

625

763

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

626

764

gnutls_perror(ret);

627

765

}

628

retval = -1;

766

errno = EPROTO;

629

767

goto mandos_end;

630

768

}

631

769

632

770

/* Read OpenPGP packet that contains the wanted password */

633

771

634

772

if(debug){

635

fprintf(stderr, "Retrieving pgp encrypted password from %s\n",

773

fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",

636

774

ip);

637

775

}

638

776

639

777

while(true){

640

buffer_capacity = adjustbuffer(&buffer, buffer_length,

778

779

if(quit_now){

780

errno = EINTR;

781

goto mandos_end;

782

}

783

784

buffer_capacity = incbuffer(&buffer, buffer_length,

641

785

buffer_capacity);

642

786

if(buffer_capacity == 0){

643

perror("adjustbuffer");

644

retval = -1;

787

int e = errno;

788

perror("incbuffer");

789

errno = e;

790

goto mandos_end;

791

}

792

793

if(quit_now){

794

errno = EINTR;

645

795

goto mandos_end;

646

796

}

647

797

656

806

case GNUTLS_E_AGAIN:

657

807

break;

658

808

case GNUTLS_E_REHANDSHAKE:

659

do{

809

do {

660

810

ret = gnutls_handshake(session);

811

812

if(quit_now){

813

errno = EINTR;

814

goto mandos_end;

815

}

661

816

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

662

817

if(ret < 0){

663

818

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

664

819

gnutls_perror(ret);

665

retval = -1;

820

errno = EPROTO;

666

821

goto mandos_end;

667

822

}

668

823

break;

669

824

default:

670

825

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

671

826

" encrypted session with Mandos server\n");

672

retval = -1;

673

827

gnutls_bye(session, GNUTLS_SHUT_RDWR);

828

errno = EIO;

674

829

goto mandos_end;

675

830

}

676

831

} else {

682

837

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

683

838

}

684

839

685

gnutls_bye(session, GNUTLS_SHUT_RDWR);

840

if(quit_now){

841

errno = EINTR;

842

goto mandos_end;

843

}

844

845

do {

846

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

847

if(quit_now){

848

errno = EINTR;

849

goto mandos_end;

850

}

851

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

686

852

687

853

if(buffer_length > 0){

688

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

854

ssize_t decrypted_buffer_size;

855

decrypted_buffer_size = pgp_packet_decrypt(buffer,

689

856

buffer_length,

690

857

&decrypted_buffer);

691

858

if(decrypted_buffer_size >= 0){

859

692

860

written = 0;

693

861

while(written < (size_t) decrypted_buffer_size){

862

if(quit_now){

863

errno = EINTR;

864

goto mandos_end;

865

}

866

694

867

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

695

868

(size_t)decrypted_buffer_size - written,

696

869

stdout);

697

870

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

871

int e = errno;

698

872

if(debug){

699

873

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

700

874

strerror(errno));

701

875

}

702

retval = -1;

703

break;

876

errno = e;

877

goto mandos_end;

704

878

}

705

879

written += (size_t)ret;

706

880

}

707

free(decrypted_buffer);

708

} else {

709

retval = -1;

881

retval = 0;

710

882

}

711

} else {

712

retval = -1;

713

883

}

714

884

715

885

/* Shutdown procedure */

716

886

717

887

mandos_end:

718

free(buffer);

719

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

720

if(ret == -1){

721

perror("close");

888

{

889

int e = errno;

890

free(decrypted_buffer);

891

free(buffer);

892

if(tcp_sd >= 0){

893

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

894

}

895

if(ret == -1){

896

if(e == 0){

897

e = errno;

898

}

899

perror("close");

900

}

901

gnutls_deinit(session);

902

if(quit_now){

903

e = EINTR;

904

retval = -1;

905

}

906

errno = e;

722

907

}

723

gnutls_deinit(session);

724

908

return retval;

725

909

}

726

910

727

911

static void resolve_callback(AvahiSServiceResolver *r,

728

912

AvahiIfIndex interface,

729

AVAHI_GCC_UNUSED AvahiProtocol protocol,

913

AvahiProtocol proto,

730

914

AvahiResolverEvent event,

731

915

const char *name,

732

916

const char *type,

737

921

AVAHI_GCC_UNUSED AvahiStringList *txt,

738

922

AVAHI_GCC_UNUSED AvahiLookupResultFlags

739

923

flags,

740

void* userdata){

741

mandos_context *mc = userdata;

924

AVAHI_GCC_UNUSED void* userdata){

742

925

assert(r);

743

926

744

927

/* Called whenever a service has been resolved successfully or

745

928

timed out */

746

929

930

if(quit_now){

931

return;

932

}

933

747

934

switch(event){

748

935

default:

749

936

case AVAHI_RESOLVER_FAILURE:

750

937

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

751

938

" of type '%s' in domain '%s': %s\n", name, type, domain,

752

avahi_strerror(avahi_server_errno(mc->server)));

939

avahi_strerror(avahi_server_errno(mc.server)));

753

940

break;

754

941

755

942

case AVAHI_RESOLVER_FOUND:

761

948

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

762

949

ip, (intmax_t)interface, port);

763

950

}

764

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

951

int ret = start_mandos_communication(ip, port, interface,

952

avahi_proto_to_af(proto));

765

953

if(ret == 0){

766

avahi_simple_poll_quit(mc->simple_poll);

954

avahi_simple_poll_quit(mc.simple_poll);

767

955

}

768

956

}

769

957

}

779

967

const char *domain,

780

968

AVAHI_GCC_UNUSED AvahiLookupResultFlags

781

969

flags,

782

void* userdata){

783

mandos_context *mc = userdata;

970

AVAHI_GCC_UNUSED void* userdata){

784

971

assert(b);

785

972

786

973

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

787

974

is removed from the LAN */

788

975

976

if(quit_now){

977

return;

978

}

979

789

980

switch(event){

790

981

default:

791

982

case AVAHI_BROWSER_FAILURE:

792

983

793

984

fprintf(stderr, "(Avahi browser) %s\n",

794

avahi_strerror(avahi_server_errno(mc->server)));

795

avahi_simple_poll_quit(mc->simple_poll);

985

avahi_strerror(avahi_server_errno(mc.server)));

986

avahi_simple_poll_quit(mc.simple_poll);

796

987

return;

797

988

798

989

case AVAHI_BROWSER_NEW:

801

992

the callback function is called the Avahi server will free the

802

993

resolver for us. */

803

994

804

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

805

protocol, name, type, domain,

806

AVAHI_PROTO_INET6, 0,

807

resolve_callback, mc)))

995

if(avahi_s_service_resolver_new(mc.server, interface, protocol,

996

name, type, domain, protocol, 0,

997

resolve_callback, NULL) == NULL)

808

998

fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",

809

name, avahi_strerror(avahi_server_errno(mc->server)));

999

name, avahi_strerror(avahi_server_errno(mc.server)));

810

1000

break;

811

1001

812

1002

case AVAHI_BROWSER_REMOVE:

821

1011

}

822

1012

}

823

1013

1014

/* stop main loop after sigterm has been called */

1015

static void handle_sigterm(int sig){

1016

if(quit_now){

1017

return;

1018

}

1019

quit_now = 1;

1020

signal_received = sig;

1021

int old_errno = errno;

1022

if(mc.simple_poll != NULL){

1023

avahi_simple_poll_quit(mc.simple_poll);

1024

}

1025

errno = old_errno;

1026

}

1027

1028

/*

1029

* This function determines if a directory entry in /sys/class/net

1030

* corresponds to an acceptable network device.

1031

* (This function is passed to scandir(3) as a filter function.)

1032

*/

1033

int good_interface(const struct dirent *if_entry){

1034

ssize_t ssret;

1035

char *flagname = NULL;

1036

if(if_entry->d_name[0] == '.'){

1037

return 0;

1038

}

1039

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1040

if_entry->d_name);

1041

if(ret < 0){

1042

perror("asprintf");

1043

return 0;

1044

}

1045

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1046

if(flags_fd == -1){

1047

perror("open");

1048

free(flagname);

1049

return 0;

1050

}

1051

free(flagname);

1052

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1053

/* read line from flags_fd */

1054

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1055

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1056

flagstring[(size_t)to_read] = '\0';

1057

if(flagstring == NULL){

1058

perror("malloc");

1059

close(flags_fd);

1060

return 0;

1061

}

1062

while(to_read > 0){

1063

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1064

(size_t)to_read));

1065

if(ssret == -1){

1066

perror("read");

1067

free(flagstring);

1068

close(flags_fd);

1069

return 0;

1070

}

1071

to_read -= ssret;

1072

if(ssret == 0){

1073

break;

1074

}

1075

}

1076

close(flags_fd);

1077

intmax_t tmpmax;

1078

char *tmp;

1079

errno = 0;

1080

tmpmax = strtoimax(flagstring, &tmp, 0);

1081

if(errno != 0 or tmp == flagstring or (*tmp != '\0'

1082

and not (isspace(*tmp)))

1083

or tmpmax != (ifreq_flags)tmpmax){

1084

if(debug){

1085

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1086

flagstring, if_entry->d_name);

1087

}

1088

free(flagstring);

1089

return 0;

1090

}

1091

free(flagstring);

1092

ifreq_flags flags = (ifreq_flags)tmpmax;

1093

/* Reject the loopback device */

1094

if(flags & IFF_LOOPBACK){

1095

if(debug){

1096

fprintf(stderr, "Rejecting loopback interface \"%s\"\n",

1097

if_entry->d_name);

1098

}

1099

return 0;

1100

}

1101

/* Accept point-to-point devices only if connect_to is specified */

1102

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1103

if(debug){

1104

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1105

if_entry->d_name);

1106

}

1107

return 1;

1108

}

1109

/* Otherwise, reject non-broadcast-capable devices */

1110

if(not (flags & IFF_BROADCAST)){

1111

if(debug){

1112

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1113

if_entry->d_name);

1114

}

1115

return 0;

1116

}

1117

/* Reject non-ARP interfaces (including dummy interfaces) */

1118

if(flags & IFF_NOARP){

1119

if(debug){

1120

fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",

1121

if_entry->d_name);

1122

}

1123

return 0;

1124

}

1125

/* Accept this device */

1126

if(debug){

1127

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1128

if_entry->d_name);

1129

}

1130

return 1;

1131

}

1132

1133

int notdotentries(const struct dirent *direntry){

1134

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

1135

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

1136

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

1137

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

1138

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

1139

return 0;

1140

}

1141

return 1;

1142

}

1143

824

1144

int main(int argc, char *argv[]){

825

1145

AvahiSServiceBrowser *sb = NULL;

826

1146

int error;

827

1147

int ret;

828

1148

intmax_t tmpmax;

829

int numchars;

1149

char *tmp;

830

1150

int exitcode = EXIT_SUCCESS;

831

const char *interface = "eth0";

1151

const char *interface = "";

832

1152

struct ifreq network;

833

int sd;

1153

int sd = -1;

1154

bool take_down_interface = false;

834

1155

uid_t uid;

835

1156

gid_t gid;

836

char *connect_to = NULL;

837

1157

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

838

1158

bool tempdir_created = false;

839

1159

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

840

1160

const char *seckey = PATHDIR "/" SECKEY;

841

1161

const char *pubkey = PATHDIR "/" PUBKEY;

842

1162

843

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

844

.dh_bits = 1024, .priority = "SECURE256"

845

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

846

1163

bool gnutls_initialized = false;

847

1164

bool gpgme_initialized = false;

848

double delay = 2.5;

1165

float delay = 2.5f;

1166

1167

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1168

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1169

1170

uid = getuid();

1171

gid = getgid();

1172

1173

/* Lower any group privileges we might have, just to be safe */

1174

errno = 0;

1175

ret = setgid(gid);

1176

if(ret == -1){

1177

perror("setgid");

1178

}

1179

1180

/* Lower user privileges (temporarily) */

1181

errno = 0;

1182

ret = seteuid(uid);

1183

if(ret == -1){

1184

perror("seteuid");

1185

}

1186

1187

if(quit_now){

1188

goto end;

1189

}

849

1190

850

1191

{

851

1192

struct argp_option options[] = {

857

1198

.group = 1 },

858

1199

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

859

1200

.arg = "NAME",

860

.doc = "Interface that will be used to search for Mandos"

861

" servers",

1201

.doc = "Network interface that will be used to search for"

1202

" Mandos servers",

862

1203

.group = 1 },

863

1204

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

864

1205

.arg = "FILE",

881

1222

.arg = "SECONDS",

882

1223

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

883

1224

.group = 2 },

1225

/*

1226

* These reproduce what we would get without ARGP_NO_HELP

1227

*/

1228

{ .name = "help", .key = '?',

1229

.doc = "Give this help list", .group = -1 },

1230

{ .name = "usage", .key = -3,

1231

.doc = "Give a short usage message", .group = -1 },

1232

{ .name = "version", .key = 'V',

1233

.doc = "Print program version", .group = -1 },

884

1234

{ .name = NULL }

885

1235

};

886

1236

887

1237

error_t parse_opt(int key, char *arg,

888

1238

struct argp_state *state){

1239

errno = 0;

889

1240

switch(key){

890

1241

case 128: /* --debug */

891

1242

debug = true;

903

1254

pubkey = arg;

904

1255

break;

905

1256

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

906

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

907

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

908

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

909

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

910

exit(EXIT_FAILURE);

1257

errno = 0;

1258

tmpmax = strtoimax(arg, &tmp, 10);

1259

if(errno != 0 or tmp == arg or *tmp != '\0'

1260

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1261

argp_error(state, "Bad number of DH bits");

911

1262

}

912

1263

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

913

1264

break;

915

1266

mc.priority = arg;

916

1267

break;

917

1268

case 131: /* --delay */

918

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

919

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

920

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

921

exit(EXIT_FAILURE);

1269

errno = 0;

1270

delay = strtof(arg, &tmp);

1271

if(errno != 0 or tmp == arg or *tmp != '\0'){

1272

argp_error(state, "Bad delay");

922

1273

}

923

1274

break;

924

case ARGP_KEY_ARG:

925

argp_usage(state);

926

case ARGP_KEY_END:

1275

/*

1276

* These reproduce what we would get without ARGP_NO_HELP

1277

*/

1278

case '?': /* --help */

1279

argp_state_help(state, state->out_stream,

1280

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1281

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1282

case -3: /* --usage */

1283

argp_state_help(state, state->out_stream,

1284

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1285

case 'V': /* --version */

1286

fprintf(state->out_stream, "%s\n", argp_program_version);

1287

exit(argp_err_exit_status);

927

1288

break;

928

1289

default:

929

1290

return ARGP_ERR_UNKNOWN;

930

1291

}

931

return 0;

1292

return errno;

932

1293

}

933

1294

934

1295

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

935

1296

.args_doc = "",

936

1297

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

937

1298

" passwords from a Mandos server" };

938

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

939

if(ret == ARGP_ERR_UNKNOWN){

940

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

1299

ret = argp_parse(&argp, argc, argv,

1300

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1301

switch(ret){

1302

case 0:

1303

break;

1304

case ENOMEM:

1305

default:

1306

errno = ret;

1307

perror("argp_parse");

1308

exitcode = EX_OSERR;

1309

goto end;

1310

case EINVAL:

1311

exitcode = EX_USAGE;

1312

goto end;

1313

}

1314

}

1315

1316

if(not debug){

1317

avahi_set_log_function(empty_log);

1318

}

1319

1320

if(interface[0] == '\0'){

1321

struct dirent **direntries;

1322

ret = scandir(sys_class_net, &direntries, good_interface,

1323

alphasort);

1324

if(ret >= 1){

1325

/* Pick the first good interface */

1326

interface = strdup(direntries[0]->d_name);

1327

if(debug){

1328

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

1329

}

1330

if(interface == NULL){

1331

perror("malloc");

1332

free(direntries);

1333

exitcode = EXIT_FAILURE;

1334

goto end;

1335

}

1336

free(direntries);

1337

} else {

1338

free(direntries);

1339

fprintf(stderr, "Could not find a network interface\n");

941

1340

exitcode = EXIT_FAILURE;

942

1341

goto end;

943

1342

}

944

1343

}

945

1344

1345

/* Initialize Avahi early so avahi_simple_poll_quit() can be called

1346

from the signal handler */

1347

/* Initialize the pseudo-RNG for Avahi */

1348

srand((unsigned int) time(NULL));

1349

mc.simple_poll = avahi_simple_poll_new();

1350

if(mc.simple_poll == NULL){

1351

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

1352

exitcode = EX_UNAVAILABLE;

1353

goto end;

1354

}

1355

1356

sigemptyset(&sigterm_action.sa_mask);

1357

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1358

if(ret == -1){

1359

perror("sigaddset");

1360

exitcode = EX_OSERR;

1361

goto end;

1362

}

1363

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1364

if(ret == -1){

1365

perror("sigaddset");

1366

exitcode = EX_OSERR;

1367

goto end;

1368

}

1369

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1370

if(ret == -1){

1371

perror("sigaddset");

1372

exitcode = EX_OSERR;

1373

goto end;

1374

}

1375

/* Need to check if the handler is SIG_IGN before handling:

1376

| [[info:libc:Initial Signal Actions]] |

1377

| [[info:libc:Basic Signal Handling]] |

1378

*/

1379

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1380

if(ret == -1){

1381

perror("sigaction");

1382

return EX_OSERR;

1383

}

1384

if(old_sigterm_action.sa_handler != SIG_IGN){

1385

ret = sigaction(SIGINT, &sigterm_action, NULL);

1386

if(ret == -1){

1387

perror("sigaction");

1388

exitcode = EX_OSERR;

1389

goto end;

1390

}

1391

}

1392

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1393

if(ret == -1){

1394

perror("sigaction");

1395

return EX_OSERR;

1396

}

1397

if(old_sigterm_action.sa_handler != SIG_IGN){

1398

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1399

if(ret == -1){

1400

perror("sigaction");

1401

exitcode = EX_OSERR;

1402

goto end;

1403

}

1404

}

1405

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1406

if(ret == -1){

1407

perror("sigaction");

1408

return EX_OSERR;

1409

}

1410

if(old_sigterm_action.sa_handler != SIG_IGN){

1411

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1412

if(ret == -1){

1413

perror("sigaction");

1414

exitcode = EX_OSERR;

1415

goto end;

1416

}

1417

}

1418

946

1419

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

947

{

1420

if(strcmp(interface, "none") != 0){

1421

if_index = (AvahiIfIndex) if_nametoindex(interface);

1422

if(if_index == 0){

1423

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

1424

exitcode = EX_UNAVAILABLE;

1425

goto end;

1426

}

1427

1428

if(quit_now){

1429

goto end;

1430

}

1431

1432

/* Re-raise priviliges */

1433

errno = 0;

1434

ret = seteuid(0);

1435

if(ret == -1){

1436

perror("seteuid");

1437

}

1438

948

1439

#ifdef __linux__

949

1440

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

950

messages to mess up the prompt */

1441

messages about the network interface to mess up the prompt */

951

1442

ret = klogctl(8, NULL, 5);

1443

bool restore_loglevel = true;

952

1444

if(ret == -1){

1445

restore_loglevel = false;

953

1446

perror("klogctl");

954

1447

}

955

#endif

1448

#endif /* __linux__ */

956

1449

957

1450

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

958

1451

if(sd < 0){

959

1452

perror("socket");

960

exitcode = EXIT_FAILURE;

1453

exitcode = EX_OSERR;

961

1454

#ifdef __linux__

962

ret = klogctl(7, NULL, 0);

1455

if(restore_loglevel){

1456

ret = klogctl(7, NULL, 0);

1457

if(ret == -1){

1458

perror("klogctl");

1459

}

1460

}

1461

#endif /* __linux__ */

1462

/* Lower privileges */

1463

errno = 0;

1464

ret = seteuid(uid);

963

1465

if(ret == -1){

964

perror("klogctl");

1466

perror("seteuid");

965

1467

}

966

#endif

967

1468

goto end;

968

1469

}

969

1470

strcpy(network.ifr_name, interface);

971

1472

if(ret == -1){

972

1473

perror("ioctl SIOCGIFFLAGS");

973

1474

#ifdef __linux__

974

ret = klogctl(7, NULL, 0);

1475

if(restore_loglevel){

1476

ret = klogctl(7, NULL, 0);

1477

if(ret == -1){

1478

perror("klogctl");

1479

}

1480

}

1481

#endif /* __linux__ */

1482

exitcode = EX_OSERR;

1483

/* Lower privileges */

1484

errno = 0;

1485

ret = seteuid(uid);

975

1486

if(ret == -1){

976

perror("klogctl");

1487

perror("seteuid");

977

1488

}

978

#endif

979

exitcode = EXIT_FAILURE;

980

1489

goto end;

981

1490

}

982

1491

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

983

1492

network.ifr_flags |= IFF_UP;

1493

take_down_interface = true;

984

1494

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

985

1495

if(ret == -1){

986

perror("ioctl SIOCSIFFLAGS");

987

exitcode = EXIT_FAILURE;

1496

take_down_interface = false;

1497

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1498

exitcode = EX_OSERR;

988

1499

#ifdef __linux__

989

ret = klogctl(7, NULL, 0);

1500

if(restore_loglevel){

1501

ret = klogctl(7, NULL, 0);

1502

if(ret == -1){

1503

perror("klogctl");

1504

}

1505

}

1506

#endif /* __linux__ */

1507

/* Lower privileges */

1508

errno = 0;

1509

ret = seteuid(uid);

990

1510

if(ret == -1){

991

perror("klogctl");

1511

perror("seteuid");

992

1512

}

993

#endif

994

1513

goto end;

995

1514

}

996

1515

}

1008

1527

perror("nanosleep");

1009

1528

}

1010

1529

}

1011

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

1012

if(ret == -1){

1013

perror("close");

1530

if(not take_down_interface){

1531

/* We won't need the socket anymore */

1532

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

1533

if(ret == -1){

1534

perror("close");

1535

}

1014

1536

}

1015

1537

#ifdef __linux__

1016

/* Restores kernel loglevel to default */

1017

ret = klogctl(7, NULL, 0);

1018

if(ret == -1){

1019

perror("klogctl");

1020

}

1021

#endif

1022

}

1023

1024

uid = getuid();

1025

gid = getgid();

1026

1027

setgid(gid);

1028

if(ret == -1){

1029

perror("setgid");

1030

}

1031

1032

ret = setuid(uid);

1033

if(ret == -1){

1034

perror("setuid");

1035

}

1036

1037

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

1538

if(restore_loglevel){

1539

/* Restores kernel loglevel to default */

1540

ret = klogctl(7, NULL, 0);

1541

if(ret == -1){

1542

perror("klogctl");

1543

}

1544

}

1545

#endif /* __linux__ */

1546

/* Lower privileges */

1547

errno = 0;

1548

if(take_down_interface){

1549

/* Lower privileges */

1550

ret = seteuid(uid);

1551

if(ret == -1){

1552

perror("seteuid");

1553

}

1554

} else {

1555

/* Lower privileges permanently */

1556

ret = setuid(uid);

1557

if(ret == -1){

1558

perror("setuid");

1559

}

1560

}

1561

}

1562

1563

if(quit_now){

1564

goto end;

1565

}

1566

1567

ret = init_gnutls_global(pubkey, seckey);

1038

1568

if(ret == -1){

1039

1569

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

1040

exitcode = EXIT_FAILURE;

1570

exitcode = EX_UNAVAILABLE;

1041

1571

goto end;

1042

1572

} else {

1043

1573

gnutls_initialized = true;

1044

1574

}

1045

1575

1576

if(quit_now){

1577

goto end;

1578

}

1579

1046

1580

if(mkdtemp(tempdir) == NULL){

1047

1581

perror("mkdtemp");

1048

1582

goto end;

1049

1583

}

1050

1584

tempdir_created = true;

1051

1585

1052

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

1586

if(quit_now){

1587

goto end;

1588

}

1589

1590

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

1053

1591

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

1054

exitcode = EXIT_FAILURE;

1592

exitcode = EX_UNAVAILABLE;

1055

1593

goto end;

1056

1594

} else {

1057

1595

gpgme_initialized = true;

1058

1596

}

1059

1597

1060

if_index = (AvahiIfIndex) if_nametoindex(interface);

1061

if(if_index == 0){

1062

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

1063

exitcode = EXIT_FAILURE;

1598

if(quit_now){

1064

1599

goto end;

1065

1600

}

1066

1601

1070

1605

char *address = strrchr(connect_to, ':');

1071

1606

if(address == NULL){

1072

1607

fprintf(stderr, "No colon in address\n");

1073

exitcode = EXIT_FAILURE;

1074

goto end;

1075

}

1608

exitcode = EX_USAGE;

1609

goto end;

1610

}

1611

1612

if(quit_now){

1613

goto end;

1614

}

1615

1076

1616

uint16_t port;

1077

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

1078

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

1079

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

1617

errno = 0;

1618

tmpmax = strtoimax(address+1, &tmp, 10);

1619

if(errno != 0 or tmp == address+1 or *tmp != '\0'

1620

or tmpmax != (uint16_t)tmpmax){

1080

1621

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

1081

exitcode = EXIT_FAILURE;

1082

goto end;

1083

}

1622

exitcode = EX_USAGE;

1623

goto end;

1624

}

1625

1626

if(quit_now){

1627

goto end;

1628

}

1629

1084

1630

port = (uint16_t)tmpmax;

1085

1631

*address = '\0';

1086

1632

address = connect_to;

1087

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

1088

if(ret < 0){

1089

exitcode = EXIT_FAILURE;

1633

/* Colon in address indicates IPv6 */

1634

int af;

1635

if(strchr(address, ':') != NULL){

1636

af = AF_INET6;

1090

1637

} else {

1638

af = AF_INET;

1639

}

1640

1641

if(quit_now){

1642

goto end;

1643

}

1644

1645

while(not quit_now){

1646

ret = start_mandos_communication(address, port, if_index, af);

1647

if(quit_now or ret == 0){

1648

break;

1649

}

1650

sleep(15);

1651

};

1652

1653

if (not quit_now){

1091

1654

exitcode = EXIT_SUCCESS;

1092

1655

}

1656

1093

1657

goto end;

1094

1658

}

1095

1659

1096

if(not debug){

1097

avahi_set_log_function(empty_log);

1098

}

1099

1100

/* Initialize the pseudo-RNG for Avahi */

1101

srand((unsigned int) time(NULL));

1102

1103

/* Allocate main Avahi loop object */

1104

mc.simple_poll = avahi_simple_poll_new();

1105

if(mc.simple_poll == NULL){

1106

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

1107

exitcode = EXIT_FAILURE;

1660

if(quit_now){

1108

1661

goto end;

1109

1662

}

1110

1663

1130

1683

if(mc.server == NULL){

1131

1684

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

1132

1685

avahi_strerror(error));

1133

exitcode = EXIT_FAILURE;

1686

exitcode = EX_UNAVAILABLE;

1687

goto end;

1688

}

1689

1690

if(quit_now){

1134

1691

goto end;

1135

1692

}

1136

1693

1137

1694

/* Create the Avahi service browser */

1138

1695

sb = avahi_s_service_browser_new(mc.server, if_index,

1139

AVAHI_PROTO_INET6, "_mandos._tcp",

1140

NULL, 0, browse_callback, &mc);

1696

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1697

NULL, 0, browse_callback, NULL);

1141

1698

if(sb == NULL){

1142

1699

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

1143

1700

avahi_strerror(avahi_server_errno(mc.server)));

1144

exitcode = EXIT_FAILURE;

1701

exitcode = EX_UNAVAILABLE;

1702

goto end;

1703

}

1704

1705

if(quit_now){

1145

1706

goto end;

1146

1707

}

1147

1708

1179

1740

gpgme_release(mc.ctx);

1180

1741

}

1181

1742

1182

/* Removes the temp directory used by GPGME */

1743

/* Take down the network interface */

1744

if(take_down_interface){

1745

/* Re-raise priviliges */

1746

errno = 0;

1747

ret = seteuid(0);

1748

if(ret == -1){

1749

perror("seteuid");

1750

}

1751

if(geteuid() == 0){

1752

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

1753

if(ret == -1){

1754

perror("ioctl SIOCGIFFLAGS");

1755

} else if(network.ifr_flags & IFF_UP) {

1756

network.ifr_flags &= ~(short)IFF_UP; /* clear flag */

1757

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

1758

if(ret == -1){

1759

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1760

}

1761

}

1762

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

1763

if(ret == -1){

1764

perror("close");

1765

}

1766

/* Lower privileges permanently */

1767

errno = 0;

1768

ret = setuid(uid);

1769

if(ret == -1){

1770

perror("setuid");

1771

}

1772

}

1773

}

1774

1775

/* Removes the GPGME temp directory and all files inside */

1183

1776

if(tempdir_created){

1184

DIR *d;

1185

struct dirent *direntry;

1186

d = opendir(tempdir);

1187

if(d == NULL){

1188

if(errno != ENOENT){

1189

perror("opendir");

1190

}

1191

} else {

1192

while(true){

1193

direntry = readdir(d);

1194

if(direntry == NULL){

1195

break;

1196

}

1197

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

1198

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

1199

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

1200

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

1201

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

1202

continue;

1203

}

1777

struct dirent **direntries = NULL;

1778

struct dirent *direntry = NULL;

1779

ret = scandir(tempdir, &direntries, notdotentries, alphasort);

1780

if (ret > 0){

1781

for(int i = 0; i < ret; i++){

1782

direntry = direntries[i];

1204

1783

char *fullname = NULL;

1205

1784

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

1206

1785

direntry->d_name);

1215

1794

}

1216

1795

free(fullname);

1217

1796

}

1218

closedir(d);

1797

}

1798

1799

/* need to be cleaned even if ret == 0 because man page dont specify */

1800

free(direntries);

1801

if (ret == -1){

1802

perror("scandir");

1219

1803

}

1220

1804

ret = rmdir(tempdir);

1221

1805

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

1223

1807

}

1224

1808

}

1225

1809

1810

if(quit_now){

1811

sigemptyset(&old_sigterm_action.sa_mask);

1812

old_sigterm_action.sa_handler = SIG_DFL;

1813

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1814

&old_sigterm_action,

1815

NULL));

1816

if(ret == -1){

1817

perror("sigaction");

1818

}

1819

do {

1820

ret = raise(signal_received);

1821

} while(ret != 0 and errno == EINTR);

1822

if(ret != 0){

1823

perror("raise");

1824

abort();

1825

}

1826

TEMP_FAILURE_RETRY(pause());

1827

}

1828

1226

1829

return exitcode;

1227

1830

}