/mandos/trunk : revision 24.1.139

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

46

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

44

srand() */

45

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

47

srand(), strtof() */

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

66

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

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

74

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

71

75

setgid() */

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

78

86

#ifdef __linux__

79

87

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

80

#endif

88

#endif /* __linux__ */

81

89

82

90

/* Avahi */

83

91

/* All Avahi types, constants and functions

129

137

gpgme_ctx_t ctx;

130

138

} mandos_context;

131

139

140

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

141

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

142

.dh_bits = 1024, .priority = "SECURE256"

143

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

144

132

145

/*

133

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

134

* "buffer_capacity" is how much is currently allocated,

146

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

147

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

135

148

* "buffer_length" is how much is already used.

136

149

*/

137

size_t adjustbuffer(char **buffer, size_t buffer_length,

150

size_t incbuffer(char **buffer, size_t buffer_length,

138

151

size_t buffer_capacity){

139

152

if(buffer_length + BUFFER_SIZE > buffer_capacity){

140

153

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

149

162

/*

150

163

* Initialize GPGME.

151

164

*/

152

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

165

static bool init_gpgme(const char *seckey,

153

166

const char *pubkey, const char *tempdir){

154

167

int ret;

155

168

gpgme_error_t rc;

176

189

return false;

177

190

}

178

191

179

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

192

rc = gpgme_op_import(mc.ctx, pgp_data);

180

193

if(rc != GPG_ERR_NO_ERROR){

181

194

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

182

195

gpgme_strsource(rc), gpgme_strerror(rc));

192

205

}

193

206

194

207

if(debug){

195

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

208

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

196

209

}

197

210

198

211

/* Init GPGME */

225

238

}

226

239

227

240

/* Create new GPGME "context" */

228

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

241

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

229

242

if(rc != GPG_ERR_NO_ERROR){

230

243

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

231

244

gpgme_strsource(rc), gpgme_strerror(rc));

236

249

return false;

237

250

}

238

251

239

return true;

252

return true;

240

253

}

241

254

242

255

/*

243

256

* Decrypt OpenPGP data.

244

257

* Returns -1 on error

245

258

*/

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

259

static ssize_t pgp_packet_decrypt(const char *cryptotext,

248

260

size_t crypto_size,

249

261

char **plaintext){

250

262

gpgme_data_t dh_crypto, dh_plain;

277

289

278

290

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

279

291

data buffer */

280

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

292

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

281

293

if(rc != GPG_ERR_NO_ERROR){

282

294

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

283

295

gpgme_strsource(rc), gpgme_strerror(rc));

284

296

plaintext_length = -1;

285

297

if(debug){

286

298

gpgme_decrypt_result_t result;

287

result = gpgme_op_decrypt_result(mc->ctx);

299

result = gpgme_op_decrypt_result(mc.ctx);

288

300

if(result == NULL){

289

301

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

290

302

} else {

297

309

}

298

310

gpgme_recipient_t recipient;

299

311

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

}

312

while(recipient != NULL){

313

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

314

gpgme_pubkey_algo_name(recipient->pubkey_algo));

315

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

316

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

317

recipient->status == GPG_ERR_NO_SECKEY

318

? "No" : "Yes");

319

recipient = recipient->next;

310

320

}

311

321

}

312

322

}

326

336

327

337

*plaintext = NULL;

328

338

while(true){

329

plaintext_capacity = adjustbuffer(plaintext,

339

plaintext_capacity = incbuffer(plaintext,

330

340

(size_t)plaintext_length,

331

341

plaintext_capacity);

332

342

if(plaintext_capacity == 0){

333

perror("adjustbuffer");

343

perror("incbuffer");

334

344

plaintext_length = -1;

335

345

goto decrypt_end;

336

346

}

382

392

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

383

393

}

384

394

385

static int init_gnutls_global(mandos_context *mc,

386

const char *pubkeyfilename,

395

static int init_gnutls_global(const char *pubkeyfilename,

387

396

const char *seckeyfilename){

388

397

int ret;

389

398

407

416

}

408

417

409

418

/* OpenPGP credentials */

410

gnutls_certificate_allocate_credentials(&mc->cred);

419

gnutls_certificate_allocate_credentials(&mc.cred);

411

420

if(ret != GNUTLS_E_SUCCESS){

412

421

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

413

* from

414

* -Wunreachable-code

415

*/

422

from

423

-Wunreachable-code

424

*/

416

425

safer_gnutls_strerror(ret));

417

426

gnutls_global_deinit();

418

427

return -1;

425

434

}

426

435

427

436

ret = gnutls_certificate_set_openpgp_key_file

428

(mc->cred, pubkeyfilename, seckeyfilename,

437

(mc.cred, pubkeyfilename, seckeyfilename,

429

438

GNUTLS_OPENPGP_FMT_BASE64);

430

439

if(ret != GNUTLS_E_SUCCESS){

431

440

fprintf(stderr,

437

446

}

438

447

439

448

/* GnuTLS server initialization */

440

ret = gnutls_dh_params_init(&mc->dh_params);

449

ret = gnutls_dh_params_init(&mc.dh_params);

441

450

if(ret != GNUTLS_E_SUCCESS){

442

451

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

443

452

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

444

453

goto globalfail;

445

454

}

446

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

455

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

447

456

if(ret != GNUTLS_E_SUCCESS){

448

457

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

449

458

safer_gnutls_strerror(ret));

450

459

goto globalfail;

451

460

}

452

461

453

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

462

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

454

463

455

464

return 0;

456

465

457

466

globalfail:

458

467

459

gnutls_certificate_free_credentials(mc->cred);

468

gnutls_certificate_free_credentials(mc.cred);

460

469

gnutls_global_deinit();

461

gnutls_dh_params_deinit(mc->dh_params);

470

gnutls_dh_params_deinit(mc.dh_params);

462

471

return -1;

463

472

}

464

473

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

474

static int init_gnutls_session(gnutls_session_t *session){

467

475

int ret;

468

476

/* GnuTLS session creation */

469

477

ret = gnutls_init(session, GNUTLS_SERVER);

474

482

475

483

{

476

484

const char *err;

477

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

485

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

478

486

if(ret != GNUTLS_E_SUCCESS){

479

487

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

480

488

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

485

493

}

486

494

487

495

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

496

mc.cred);

489

497

if(ret != GNUTLS_E_SUCCESS){

490

498

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

491

499

safer_gnutls_strerror(ret));

497

505

gnutls_certificate_server_set_request(*session,

498

506

GNUTLS_CERT_IGNORE);

499

507

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

508

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

501

509

502

510

return 0;

503

511

}

506

514

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

507

515

__attribute__((unused)) const char *txt){}

508

516

517

sig_atomic_t quit_now = 0;

518

int signal_received = 0;

519

509

520

/* Called when a Mandos server is found */

510

521

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

511

522

AvahiIfIndex if_index,

512

mandos_context *mc){

513

int ret, tcp_sd;

523

int af){

524

int ret, tcp_sd = -1;

514

525

ssize_t sret;

515

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

526

union {

527

struct sockaddr_in in;

528

struct sockaddr_in6 in6;

529

} to;

516

530

char *buffer = NULL;

517

531

char *decrypted_buffer;

518

532

size_t buffer_length = 0;

520

534

ssize_t decrypted_buffer_size;

521

535

size_t written;

522

536

int retval = 0;

523

char interface[IF_NAMESIZE];

524

537

gnutls_session_t session;

525

526

ret = init_gnutls_session(mc, &session);

538

int pf; /* Protocol family */

539

540

if(quit_now){

541

return -1;

542

}

543

544

switch(af){

545

case AF_INET6:

546

pf = PF_INET6;

547

break;

548

case AF_INET:

549

pf = PF_INET;

550

break;

551

default:

552

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

553

return -1;

554

}

555

556

ret = init_gnutls_session(&session);

527

557

if(ret != 0){

528

558

return -1;

529

559

}

530

560

531

561

if(debug){

532

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

562

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

533

563

"\n", ip, port);

534

564

}

535

565

536

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

566

tcp_sd = socket(pf, SOCK_STREAM, 0);

537

567

if(tcp_sd < 0){

538

568

perror("socket");

539

return -1;

569

retval = -1;

570

goto mandos_end;

540

571

}

541

572

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);

573

if(quit_now){

574

goto mandos_end;

548

575

}

549

576

550

577

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);

578

if(af == AF_INET6){

579

to.in6.sin6_family = (sa_family_t)af;

580

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

581

} else { /* IPv4 */

582

to.in.sin_family = (sa_family_t)af;

583

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

584

}

555

585

if(ret < 0 ){

556

586

perror("inet_pton");

557

return -1;

587

retval = -1;

588

goto mandos_end;

558

589

}

559

590

if(ret == 0){

560

591

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

561

return -1;

592

retval = -1;

593

goto mandos_end;

562

594

}

563

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

595

if(af == AF_INET6){

596

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

597

-Wconversion and

598

-Wunreachable-code */

599

600

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

601

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

602

-Wunreachable-code*/

603

if(if_index == AVAHI_IF_UNSPEC){

604

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

605

" without a network interface\n");

606

retval = -1;

607

goto mandos_end;

608

}

609

/* Set the network interface number as scope */

610

to.in6.sin6_scope_id = (uint32_t)if_index;

611

}

612

} else {

613

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

564

614

-Wconversion and

565

615

-Wunreachable-code */

616

}

566

617

567

to.in6.sin6_scope_id = (uint32_t)if_index;

618

if(quit_now){

619

goto mandos_end;

620

}

568

621

569

622

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){

623

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

624

char interface[IF_NAMESIZE];

625

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

626

perror("if_indextoname");

627

} else {

628

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

629

ip, interface, port);

630

}

631

} else {

632

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

633

port);

634

}

635

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

636

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

637

const char *pcret;

638

if(af == AF_INET6){

639

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

640

sizeof(addrstr));

641

} else {

642

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

643

sizeof(addrstr));

644

}

645

if(pcret == NULL){

575

646

perror("inet_ntop");

576

647

} else {

577

648

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

580

651

}

581

652

}

582

653

583

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

654

if(quit_now){

655

goto mandos_end;

656

}

657

658

if(af == AF_INET6){

659

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

660

} else {

661

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

662

}

584

663

if(ret < 0){

585

664

perror("connect");

586

return -1;

665

retval = -1;

666

goto mandos_end;

667

}

668

669

if(quit_now){

670

goto mandos_end;

587

671

}

588

672

589

673

const char *out = mandos_protocol_version;

608

692

break;

609

693

}

610

694

}

695

696

if(quit_now){

697

goto mandos_end;

698

}

611

699

}

612

700

613

701

if(debug){

614

702

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

615

703

}

616

704

705

if(quit_now){

706

goto mandos_end;

707

}

708

617

709

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

618

710

711

if(quit_now){

712

goto mandos_end;

713

}

714

619

715

do{

620

716

ret = gnutls_handshake(session);

717

if(quit_now){

718

goto mandos_end;

719

}

621

720

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

622

721

623

722

if(ret != GNUTLS_E_SUCCESS){

632

731

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

633

732

634

733

if(debug){

635

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

734

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

636

735

ip);

637

736

}

638

737

639

738

while(true){

640

buffer_capacity = adjustbuffer(&buffer, buffer_length,

739

740

if(quit_now){

741

goto mandos_end;

742

}

743

744

buffer_capacity = incbuffer(&buffer, buffer_length,

641

745

buffer_capacity);

642

746

if(buffer_capacity == 0){

643

perror("adjustbuffer");

747

perror("incbuffer");

644

748

retval = -1;

645

749

goto mandos_end;

646

750

}

647

751

752

if(quit_now){

753

goto mandos_end;

754

}

755

648

756

sret = gnutls_record_recv(session, buffer+buffer_length,

649

757

BUFFER_SIZE);

650

758

if(sret == 0){

658

766

case GNUTLS_E_REHANDSHAKE:

659

767

do{

660

768

ret = gnutls_handshake(session);

769

770

if(quit_now){

771

goto mandos_end;

772

}

661

773

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

662

774

if(ret < 0){

663

775

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

682

794

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

683

795

}

684

796

797

if(quit_now){

798

goto mandos_end;

799

}

800

685

801

gnutls_bye(session, GNUTLS_SHUT_RDWR);

686

802

803

if(quit_now){

804

goto mandos_end;

805

}

806

687

807

if(buffer_length > 0){

688

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

808

decrypted_buffer_size = pgp_packet_decrypt(buffer,

689

809

buffer_length,

690

810

&decrypted_buffer);

691

811

if(decrypted_buffer_size >= 0){

692

812

written = 0;

693

813

while(written < (size_t) decrypted_buffer_size){

814

if(quit_now){

815

goto mandos_end;

816

}

817

694

818

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

695

819

(size_t)decrypted_buffer_size - written,

696

820

stdout);

716

840

717

841

mandos_end:

718

842

free(buffer);

719

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

843

if(tcp_sd >= 0){

844

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

845

}

720

846

if(ret == -1){

721

847

perror("close");

722

848

}

723

849

gnutls_deinit(session);

850

if(quit_now){

851

retval = -1;

852

}

724

853

return retval;

725

854

}

726

855

727

856

static void resolve_callback(AvahiSServiceResolver *r,

728

857

AvahiIfIndex interface,

729

AVAHI_GCC_UNUSED AvahiProtocol protocol,

858

AvahiProtocol proto,

730

859

AvahiResolverEvent event,

731

860

const char *name,

732

861

const char *type,

737

866

AVAHI_GCC_UNUSED AvahiStringList *txt,

738

867

AVAHI_GCC_UNUSED AvahiLookupResultFlags

739

868

flags,

740

void* userdata){

741

mandos_context *mc = userdata;

869

AVAHI_GCC_UNUSED void* userdata){

742

870

assert(r);

743

871

744

872

/* Called whenever a service has been resolved successfully or

745

873

timed out */

746

874

875

if(quit_now){

876

return;

877

}

878

747

879

switch(event){

748

880

default:

749

881

case AVAHI_RESOLVER_FAILURE:

750

882

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

751

883

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

752

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

884

avahi_strerror(avahi_server_errno(mc.server)));

753

885

break;

754

886

755

887

case AVAHI_RESOLVER_FOUND:

761

893

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

762

894

ip, (intmax_t)interface, port);

763

895

}

764

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

896

int ret = start_mandos_communication(ip, port, interface,

897

avahi_proto_to_af(proto));

765

898

if(ret == 0){

766

avahi_simple_poll_quit(mc->simple_poll);

899

avahi_simple_poll_quit(mc.simple_poll);

767

900

}

768

901

}

769

902

}

779

912

const char *domain,

780

913

AVAHI_GCC_UNUSED AvahiLookupResultFlags

781

914

flags,

782

void* userdata){

783

mandos_context *mc = userdata;

915

AVAHI_GCC_UNUSED void* userdata){

784

916

assert(b);

785

917

786

918

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

787

919

is removed from the LAN */

788

920

921

if(quit_now){

922

return;

923

}

924

789

925

switch(event){

790

926

default:

791

927

case AVAHI_BROWSER_FAILURE:

792

928

793

929

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

794

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

795

avahi_simple_poll_quit(mc->simple_poll);

930

avahi_strerror(avahi_server_errno(mc.server)));

931

avahi_simple_poll_quit(mc.simple_poll);

796

932

return;

797

933

798

934

case AVAHI_BROWSER_NEW:

801

937

the callback function is called the Avahi server will free the

802

938

resolver for us. */

803

939

804

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

805

protocol, name, type, domain,

806

AVAHI_PROTO_INET6, 0,

807

resolve_callback, mc)))

940

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

941

name, type, domain, protocol, 0,

942

resolve_callback, NULL) == NULL)

808

943

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

809

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

944

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

810

945

break;

811

946

812

947

case AVAHI_BROWSER_REMOVE:

821

956

}

822

957

}

823

958

959

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

960

static void handle_sigterm(int sig){

961

if(quit_now){

962

return;

963

}

964

quit_now = 1;

965

signal_received = sig;

966

int old_errno = errno;

967

if(mc.simple_poll != NULL){

968

avahi_simple_poll_quit(mc.simple_poll);

969

}

970

errno = old_errno;

971

}

972

824

973

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

825

974

AvahiSServiceBrowser *sb = NULL;

826

975

int error;

827

976

int ret;

828

977

intmax_t tmpmax;

829

int numchars;

978

char *tmp;

830

979

int exitcode = EXIT_SUCCESS;

831

980

const char *interface = "eth0";

832

981

struct ifreq network;

833

int sd;

982

int sd = -1;

983

bool take_down_interface = false;

834

984

uid_t uid;

835

985

gid_t gid;

836

986

char *connect_to = NULL;

840

990

const char *seckey = PATHDIR "/" SECKEY;

841

991

const char *pubkey = PATHDIR "/" PUBKEY;

842

992

843

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

844

.dh_bits = 1024, .priority = "SECURE256"

845

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

846

993

bool gnutls_initialized = false;

847

994

bool gpgme_initialized = false;

848

double delay = 2.5;

995

float delay = 2.5f;

996

997

struct sigaction old_sigterm_action;

998

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

849

999

850

1000

{

851

1001

struct argp_option options[] = {

857

1007

.group = 1 },

858

1008

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

859

1009

.arg = "NAME",

860

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

861

" servers",

1010

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

1011

" Mandos servers",

862

1012

.group = 1 },

863

1013

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

864

1014

.arg = "FILE",

903

1053

pubkey = arg;

904

1054

break;

905

1055

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'){

1056

errno = 0;

1057

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

1058

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

1059

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

909

1060

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

910

1061

exit(EXIT_FAILURE);

911

1062

}

915

1066

mc.priority = arg;

916

1067

break;

917

1068

case 131: /* --delay */

918

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

919

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

1069

errno = 0;

1070

delay = strtof(arg, &tmp);

1071

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

920

1072

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

921

1073

exit(EXIT_FAILURE);

922

1074

}

943

1095

}

944

1096

}

945

1097

1098

if(not debug){

1099

avahi_set_log_function(empty_log);

1100

}

1101

1102

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

1103

from the signal handler */

1104

/* Initialize the pseudo-RNG for Avahi */

1105

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

1106

mc.simple_poll = avahi_simple_poll_new();

1107

if(mc.simple_poll == NULL){

1108

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

1109

exitcode = EXIT_FAILURE;

1110

goto end;

1111

}

1112

1113

sigemptyset(&sigterm_action.sa_mask);

1114

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

1115

if(ret == -1){

1116

perror("sigaddset");

1117

exitcode = EXIT_FAILURE;

1118

goto end;

1119

}

1120

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

1121

if(ret == -1){

1122

perror("sigaddset");

1123

exitcode = EXIT_FAILURE;

1124

goto end;

1125

}

1126

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

1127

if(ret == -1){

1128

perror("sigaddset");

1129

exitcode = EXIT_FAILURE;

1130

goto end;

1131

}

1132

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

1133

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

1134

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

1135

*/

1136

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

1137

if(ret == -1){

1138

perror("sigaction");

1139

return EXIT_FAILURE;

1140

}

1141

if(old_sigterm_action.sa_handler != SIG_IGN){

1142

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

1143

if(ret == -1){

1144

perror("sigaction");

1145

exitcode = EXIT_FAILURE;

1146

goto end;

1147

}

1148

}

1149

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

1150

if(ret == -1){

1151

perror("sigaction");

1152

return EXIT_FAILURE;

1153

}

1154

if(old_sigterm_action.sa_handler != SIG_IGN){

1155

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

1156

if(ret == -1){

1157

perror("sigaction");

1158

exitcode = EXIT_FAILURE;

1159

goto end;

1160

}

1161

}

1162

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

1163

if(ret == -1){

1164

perror("sigaction");

1165

return EXIT_FAILURE;

1166

}

1167

if(old_sigterm_action.sa_handler != SIG_IGN){

1168

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

1169

if(ret == -1){

1170

perror("sigaction");

1171

exitcode = EXIT_FAILURE;

1172

goto end;

1173

}

1174

}

1175

946

1176

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

947

{

1177

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

1178

if_index = (AvahiIfIndex) if_nametoindex(interface);

1179

if(if_index == 0){

1180

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

1181

exitcode = EXIT_FAILURE;

1182

goto end;

1183

}

1184

1185

if(quit_now){

1186

goto end;

1187

}

1188

948

1189

#ifdef __linux__

949

1190

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

950

1191

messages to mess up the prompt */

951

1192

ret = klogctl(8, NULL, 5);

1193

bool restore_loglevel = true;

952

1194

if(ret == -1){

1195

restore_loglevel = false;

953

1196

perror("klogctl");

954

1197

}

955

#endif

1198

#endif /* __linux__ */

956

1199

957

1200

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

958

1201

if(sd < 0){

959

1202

perror("socket");

960

1203

exitcode = EXIT_FAILURE;

961

1204

#ifdef __linux__

962

ret = klogctl(7, NULL, 0);

963

if(ret == -1){

964

perror("klogctl");

1205

if(restore_loglevel){

1206

ret = klogctl(7, NULL, 0);

1207

if(ret == -1){

1208

perror("klogctl");

1209

}

965

1210

}

966

#endif

1211

#endif /* __linux__ */

967

1212

goto end;

968

1213

}

969

1214

strcpy(network.ifr_name, interface);

971

1216

if(ret == -1){

972

1217

perror("ioctl SIOCGIFFLAGS");

973

1218

#ifdef __linux__

974

ret = klogctl(7, NULL, 0);

975

if(ret == -1){

976

perror("klogctl");

1219

if(restore_loglevel){

1220

ret = klogctl(7, NULL, 0);

1221

if(ret == -1){

1222

perror("klogctl");

1223

}

977

1224

}

978

#endif

1225

#endif /* __linux__ */

979

1226

exitcode = EXIT_FAILURE;

980

1227

goto end;

981

1228

}

982

1229

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

983

1230

network.ifr_flags |= IFF_UP;

1231

take_down_interface = true;

984

1232

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

985

1233

if(ret == -1){

1234

take_down_interface = false;

986

1235

perror("ioctl SIOCSIFFLAGS");

987

1236

exitcode = EXIT_FAILURE;

988

1237

#ifdef __linux__

989

ret = klogctl(7, NULL, 0);

990

if(ret == -1){

991

perror("klogctl");

1238

if(restore_loglevel){

1239

ret = klogctl(7, NULL, 0);

1240

if(ret == -1){

1241

perror("klogctl");

1242

}

992

1243

}

993

#endif

1244

#endif /* __linux__ */

994

1245

goto end;

995

1246

}

996

1247

}

1008

1259

perror("nanosleep");

1009

1260

}

1010

1261

}

1011

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

1012

if(ret == -1){

1013

perror("close");

1262

if(not take_down_interface){

1263

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

1264

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

1265

if(ret == -1){

1266

perror("close");

1267

}

1014

1268

}

1015

1269

#ifdef __linux__

1016

/* Restores kernel loglevel to default */

1017

ret = klogctl(7, NULL, 0);

1018

if(ret == -1){

1019

perror("klogctl");

1270

if(restore_loglevel){

1271

/* Restores kernel loglevel to default */

1272

ret = klogctl(7, NULL, 0);

1273

if(ret == -1){

1274

perror("klogctl");

1275

}

1020

1276

}

1021

#endif

1277

#endif /* __linux__ */

1278

}

1279

1280

if(quit_now){

1281

goto end;

1022

1282

}

1023

1283

1024

1284

uid = getuid();

1025

1285

gid = getgid();

1026

1286

1287

errno = 0;

1027

1288

setgid(gid);

1028

1289

if(ret == -1){

1029

1290

perror("setgid");

1034

1295

perror("setuid");

1035

1296

}

1036

1297

1037

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

1298

if(quit_now){

1299

goto end;

1300

}

1301

1302

ret = init_gnutls_global(pubkey, seckey);

1038

1303

if(ret == -1){

1039

1304

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

1040

1305

exitcode = EXIT_FAILURE;

1043

1308

gnutls_initialized = true;

1044

1309

}

1045

1310

1311

if(quit_now){

1312

goto end;

1313

}

1314

1315

tempdir_created = true;

1046

1316

if(mkdtemp(tempdir) == NULL){

1317

tempdir_created = false;

1047

1318

perror("mkdtemp");

1048

1319

goto end;

1049

1320

}

1050

tempdir_created = true;

1051

1052

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

1321

1322

if(quit_now){

1323

goto end;

1324

}

1325

1326

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

1053

1327

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

1054

1328

exitcode = EXIT_FAILURE;

1055

1329

goto end;

1057

1331

gpgme_initialized = true;

1058

1332

}

1059

1333

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;

1334

if(quit_now){

1064

1335

goto end;

1065

1336

}

1066

1337

1073

1344

exitcode = EXIT_FAILURE;

1074

1345

goto end;

1075

1346

}

1347

1348

if(quit_now){

1349

goto end;

1350

}

1351

1076

1352

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'){

1353

errno = 0;

1354

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

1355

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

1356

or tmpmax != (uint16_t)tmpmax){

1080

1357

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

1081

1358

exitcode = EXIT_FAILURE;

1082

1359

goto end;

1083

1360

}

1361

1362

if(quit_now){

1363

goto end;

1364

}

1365

1084

1366

port = (uint16_t)tmpmax;

1085

1367

*address = '\0';

1086

1368

address = connect_to;

1087

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

1369

/* Colon in address indicates IPv6 */

1370

int af;

1371

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

1372

af = AF_INET6;

1373

} else {

1374

af = AF_INET;

1375

}

1376

1377

if(quit_now){

1378

goto end;

1379

}

1380

1381

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

1088

1382

if(ret < 0){

1089

1383

exitcode = EXIT_FAILURE;

1090

1384

} else {

1093

1387

goto end;

1094

1388

}

1095

1389

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;

1390

if(quit_now){

1108

1391

goto end;

1109

1392

}

1110

1393

1134

1417

goto end;

1135

1418

}

1136

1419

1420

if(quit_now){

1421

goto end;

1422

}

1423

1137

1424

/* Create the Avahi service browser */

1138

1425

sb = avahi_s_service_browser_new(mc.server, if_index,

1139

AVAHI_PROTO_INET6, "_mandos._tcp",

1140

NULL, 0, browse_callback, &mc);

1426

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1427

NULL, 0, browse_callback, NULL);

1141

1428

if(sb == NULL){

1142

1429

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

1143

1430

avahi_strerror(avahi_server_errno(mc.server)));

1145

1432

goto end;

1146

1433

}

1147

1434

1435

if(quit_now){

1436

goto end;

1437

}

1438

1148

1439

/* Run the main loop */

1149

1440

1150

1441

if(debug){

1179

1470

gpgme_release(mc.ctx);

1180

1471

}

1181

1472

1473

/* Take down the network interface */

1474

if(take_down_interface){

1475

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

1476

if(ret == -1){

1477

perror("ioctl SIOCGIFFLAGS");

1478

} else if(network.ifr_flags & IFF_UP) {

1479

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

1480

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

1481

if(ret == -1){

1482

perror("ioctl SIOCSIFFLAGS");

1483

}

1484

}

1485

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

1486

if(ret == -1){

1487

perror("close");

1488

}

1489

}

1490

1182

1491

/* Removes the temp directory used by GPGME */

1183

1492

if(tempdir_created){

1184

1493

DIR *d;

1223

1532

}

1224

1533

}

1225

1534

1535

if(quit_now){

1536

sigemptyset(&old_sigterm_action.sa_mask);

1537

old_sigterm_action.sa_handler = SIG_DFL;

1538

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

1539

if(ret == -1){

1540

perror("sigaction");

1541

}

1542

raise(signal_received);

1543

}

1544

1226

1545

return exitcode;

1227

1546

}