/mandos/release : revision 24.1.174

9

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

10

*

11

* Everything else is

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13

12

13

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*

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() */

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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 */

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45

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

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

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srand() */

46

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

47

strtof(), abort() */

45

48

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

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49

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

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50

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

56

59

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

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60

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

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61

*/

59

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

62

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

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strtoimax() */

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64

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

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

62

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

65

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

66

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

63

67

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

64

68

SIOCSIFFLAGS, if_indextoname(),

65

69

if_nametoindex(), IF_NAMESIZE */

67

71

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

68

72

*/

69

73

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

70

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

71

setgid() */

74

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

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setgid(), pause() */

72

76

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

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77

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

74

78

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

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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(),

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sigaction(), SIGTERM, sig_atomic_t,

84

raise() */

85

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

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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";

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char *connect_to = NULL;

132

133

/* Doubly linked list that need to be circular linked when ever used */

134

typedef struct server{

135

const char *ip;

136

uint16_t port;

137

AvahiIfIndex if_index;

138

int af;

139

struct timespec last_seen;

140

struct server *next;

141

struct server *prev;

142

} server;

120

143

121

144

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

122

145

typedef struct {

127

150

gnutls_dh_params_t dh_params;

128

151

const char *priority;

129

152

gpgme_ctx_t ctx;

153

server *current_server;

130

154

} mandos_context;

131

155

156

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

157

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

158

.dh_bits = 1024, .priority = "SECURE256"

159

":!CTYPE-X.509:+CTYPE-OPENPGP", .current_server = NULL };

160

161

sig_atomic_t quit_now = 0;

162

int signal_received = 0;

163

164

/* Function to use when printing errors */

165

void perror_plus(const char *print_text){

166

fprintf(stderr, "Mandos plugin %s: ", program_invocation_short_name);

167

perror(print_text);

168

}

169

132

170

/*

133

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

134

* "buffer_capacity" is how much is currently allocated,

171

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

172

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

135

173

* "buffer_length" is how much is already used.

136

174

*/

137

size_t adjustbuffer(char **buffer, size_t buffer_length,

175

size_t incbuffer(char **buffer, size_t buffer_length,

138

176

size_t buffer_capacity){

139

177

if(buffer_length + BUFFER_SIZE > buffer_capacity){

140

178

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

146

184

return buffer_capacity;

147

185

}

148

186

187

int add_server(const char *ip, uint16_t port,

188

AvahiIfIndex if_index,

189

int af){

190

int ret;

191

server *new_server = malloc(sizeof(server));

192

if(new_server == NULL){

193

perror_plus("malloc");

194

return -1;

195

}

196

*new_server = (server){ .ip = strdup(ip),

197

.port = port,

198

.if_index = if_index,

199

.af = af };

200

if(new_server->ip == NULL){

201

perror_plus("strdup");

202

return -1;

203

}

204

/* uniqe case of first server */

205

if (mc.current_server == NULL){

206

new_server->next = new_server;

207

new_server->prev = new_server;

208

mc.current_server = new_server;

209

/* Placing the new server last in the list */

210

} else {

211

new_server->next = mc.current_server;

212

new_server->prev = mc.current_server->prev;

213

new_server->prev->next = new_server;

214

mc.current_server->prev = new_server;

215

}

216

ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);

217

if(ret == -1){

218

perror_plus("clock_gettime");

219

return -1;

220

}

221

return 0;

222

}

223

149

224

/*

150

225

* Initialize GPGME.

151

226

*/

152

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

227

static bool init_gpgme(const char *seckey,

153

228

const char *pubkey, const char *tempdir){

154

int ret;

155

229

gpgme_error_t rc;

156

230

gpgme_engine_info_t engine_info;

157

231

160

234

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

161

235

*/

162

236

bool import_key(const char *filename){

237

int ret;

163

238

int fd;

164

239

gpgme_data_t pgp_data;

165

240

166

241

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

167

242

if(fd == -1){

168

perror("open");

243

perror_plus("open");

169

244

return false;

170

245

}

171

246

176

251

return false;

177

252

}

178

253

179

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

254

rc = gpgme_op_import(mc.ctx, pgp_data);

180

255

if(rc != GPG_ERR_NO_ERROR){

181

256

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

182

257

gpgme_strsource(rc), gpgme_strerror(rc));

185

260

186

261

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

187

262

if(ret == -1){

188

perror("close");

263

perror_plus("close");

189

264

}

190

265

gpgme_data_release(pgp_data);

191

266

return true;

192

267

}

193

268

194

269

if(debug){

195

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

270

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

196

271

}

197

272

198

273

/* Init GPGME */

225

300

}

226

301

227

302

/* Create new GPGME "context" */

228

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

303

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

229

304

if(rc != GPG_ERR_NO_ERROR){

230

305

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

231

306

gpgme_strsource(rc), gpgme_strerror(rc));

236

311

return false;

237

312

}

238

313

239

return true;

314

return true;

240

315

}

241

316

242

317

/*

243

318

* Decrypt OpenPGP data.

244

319

* Returns -1 on error

245

320

*/

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

321

static ssize_t pgp_packet_decrypt(const char *cryptotext,

248

322

size_t crypto_size,

249

323

char **plaintext){

250

324

gpgme_data_t dh_crypto, dh_plain;

277

351

278

352

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

279

353

data buffer */

280

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

354

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

281

355

if(rc != GPG_ERR_NO_ERROR){

282

356

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

283

357

gpgme_strsource(rc), gpgme_strerror(rc));

284

358

plaintext_length = -1;

285

359

if(debug){

286

360

gpgme_decrypt_result_t result;

287

result = gpgme_op_decrypt_result(mc->ctx);

361

result = gpgme_op_decrypt_result(mc.ctx);

288

362

if(result == NULL){

289

363

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

290

364

} else {

297

371

}

298

372

gpgme_recipient_t recipient;

299

373

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

}

374

while(recipient != NULL){

375

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

376

gpgme_pubkey_algo_name(recipient->pubkey_algo));

377

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

378

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

379

recipient->status == GPG_ERR_NO_SECKEY

380

? "No" : "Yes");

381

recipient = recipient->next;

310

382

}

311

383

}

312

384

}

319

391

320

392

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

321

393

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

322

perror("gpgme_data_seek");

394

perror_plus("gpgme_data_seek");

323

395

plaintext_length = -1;

324

396

goto decrypt_end;

325

397

}

326

398

327

399

*plaintext = NULL;

328

400

while(true){

329

plaintext_capacity = adjustbuffer(plaintext,

401

plaintext_capacity = incbuffer(plaintext,

330

402

(size_t)plaintext_length,

331

403

plaintext_capacity);

332

404

if(plaintext_capacity == 0){

333

perror("adjustbuffer");

405

perror_plus("incbuffer");

334

406

plaintext_length = -1;

335

407

goto decrypt_end;

336

408

}

343

415

break;

344

416

}

345

417

if(ret < 0){

346

perror("gpgme_data_read");

418

perror_plus("gpgme_data_read");

347

419

plaintext_length = -1;

348

420

goto decrypt_end;

349

421

}

382

454

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

383

455

}

384

456

385

static int init_gnutls_global(mandos_context *mc,

386

const char *pubkeyfilename,

457

static int init_gnutls_global(const char *pubkeyfilename,

387

458

const char *seckeyfilename){

388

459

int ret;

389

460

407

478

}

408

479

409

480

/* OpenPGP credentials */

410

gnutls_certificate_allocate_credentials(&mc->cred);

481

gnutls_certificate_allocate_credentials(&mc.cred);

411

482

if(ret != GNUTLS_E_SUCCESS){

412

483

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

413

484

from

425

496

}

426

497

427

498

ret = gnutls_certificate_set_openpgp_key_file

428

(mc->cred, pubkeyfilename, seckeyfilename,

499

(mc.cred, pubkeyfilename, seckeyfilename,

429

500

GNUTLS_OPENPGP_FMT_BASE64);

430

501

if(ret != GNUTLS_E_SUCCESS){

431

502

fprintf(stderr,

437

508

}

438

509

439

510

/* GnuTLS server initialization */

440

ret = gnutls_dh_params_init(&mc->dh_params);

511

ret = gnutls_dh_params_init(&mc.dh_params);

441

512

if(ret != GNUTLS_E_SUCCESS){

442

513

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

443

514

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

444

515

goto globalfail;

445

516

}

446

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

517

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

447

518

if(ret != GNUTLS_E_SUCCESS){

448

519

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

449

520

safer_gnutls_strerror(ret));

450

521

goto globalfail;

451

522

}

452

523

453

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

524

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

454

525

455

526

return 0;

456

527

457

528

globalfail:

458

529

459

gnutls_certificate_free_credentials(mc->cred);

530

gnutls_certificate_free_credentials(mc.cred);

460

531

gnutls_global_deinit();

461

gnutls_dh_params_deinit(mc->dh_params);

532

gnutls_dh_params_deinit(mc.dh_params);

462

533

return -1;

463

534

}

464

535

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

536

static int init_gnutls_session(gnutls_session_t *session){

467

537

int ret;

468

538

/* GnuTLS session creation */

469

ret = gnutls_init(session, GNUTLS_SERVER);

539

do {

540

ret = gnutls_init(session, GNUTLS_SERVER);

541

if(quit_now){

542

return -1;

543

}

544

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

470

545

if(ret != GNUTLS_E_SUCCESS){

471

546

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

472

547

safer_gnutls_strerror(ret));

474

549

475

550

{

476

551

const char *err;

477

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

552

do {

553

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

554

if(quit_now){

555

gnutls_deinit(*session);

556

return -1;

557

}

558

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

478

559

if(ret != GNUTLS_E_SUCCESS){

479

560

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

480

561

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

484

565

}

485

566

}

486

567

487

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

568

do {

569

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

570

mc.cred);

571

if(quit_now){

572

gnutls_deinit(*session);

573

return -1;

574

}

575

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

489

576

if(ret != GNUTLS_E_SUCCESS){

490

577

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

491

578

safer_gnutls_strerror(ret));

494

581

}

495

582

496

583

/* ignore client certificate if any. */

497

gnutls_certificate_server_set_request(*session,

498

GNUTLS_CERT_IGNORE);

584

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

499

585

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

586

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

501

587

502

588

return 0;

503

589

}

509

595

/* Called when a Mandos server is found */

510

596

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

511

597

AvahiIfIndex if_index,

512

mandos_context *mc, int af){

513

int ret, tcp_sd;

598

int af){

599

int ret, tcp_sd = -1;

514

600

ssize_t sret;

515

601

union {

516

602

struct sockaddr_in in;

517

603

struct sockaddr_in6 in6;

518

604

} to;

519

605

char *buffer = NULL;

520

char *decrypted_buffer;

606

char *decrypted_buffer = NULL;

521

607

size_t buffer_length = 0;

522

608

size_t buffer_capacity = 0;

523

ssize_t decrypted_buffer_size;

524

609

size_t written;

525

int retval = 0;

610

int retval = -1;

526

611

gnutls_session_t session;

527

612

int pf; /* Protocol family */

528

613

614

errno = 0;

615

616

if(quit_now){

617

errno = EINTR;

618

return -1;

619

}

620

529

621

switch(af){

530

622

case AF_INET6:

531

623

pf = PF_INET6;

535

627

break;

536

628

default:

537

629

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

630

errno = EINVAL;

538

631

return -1;

539

632

}

540

633

541

ret = init_gnutls_session(mc, &session);

634

ret = init_gnutls_session(&session);

542

635

if(ret != 0){

543

636

return -1;

544

637

}

550

643

551

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

552

645

if(tcp_sd < 0){

553

perror("socket");

554

return -1;

646

int e = errno;

647

perror_plus("socket");

648

errno = e;

649

goto mandos_end;

650

}

651

652

if(quit_now){

653

errno = EINTR;

654

goto mandos_end;

555

655

}

556

656

557

657

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

558

658

if(af == AF_INET6){

559

to.in6.sin6_family = (uint16_t)af;

659

to.in6.sin6_family = (sa_family_t)af;

560

660

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

561

661

} else { /* IPv4 */

562

662

to.in.sin_family = (sa_family_t)af;

563

663

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

564

664

}

565

665

if(ret < 0 ){

566

perror("inet_pton");

567

return -1;

666

int e = errno;

667

perror_plus("inet_pton");

668

errno = e;

669

goto mandos_end;

568

670

}

569

671

if(ret == 0){

672

int e = errno;

570

673

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

571

return -1;

674

errno = e;

675

goto mandos_end;

572

676

}

573

677

if(af == AF_INET6){

574

678

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

581

685

if(if_index == AVAHI_IF_UNSPEC){

582

686

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

583

687

" without a network interface\n");

584

return -1;

688

errno = EINVAL;

689

goto mandos_end;

585

690

}

586

691

/* Set the network interface number as scope */

587

692

to.in6.sin6_scope_id = (uint32_t)if_index;

592

697

-Wunreachable-code */

593

698

}

594

699

700

if(quit_now){

701

errno = EINTR;

702

goto mandos_end;

703

}

704

595

705

if(debug){

596

706

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

597

707

char interface[IF_NAMESIZE];

598

708

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

599

perror("if_indextoname");

709

perror_plus("if_indextoname");

600

710

} else {

601

711

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

602

712

ip, interface, port);

616

726

sizeof(addrstr));

617

727

}

618

728

if(pcret == NULL){

619

perror("inet_ntop");

729

perror_plus("inet_ntop");

620

730

} else {

621

731

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

622

732

fprintf(stderr, "Canonical address form: %s\n", addrstr);

624

734

}

625

735

}

626

736

737

if(quit_now){

738

errno = EINTR;

739

goto mandos_end;

740

}

741

627

742

if(af == AF_INET6){

628

743

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

629

744

} else {

630

745

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

631

746

}

632

747

if(ret < 0){

633

perror("connect");

634

return -1;

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

753

goto mandos_end;

754

}

755

756

if(quit_now){

757

errno = EINTR;

758

goto mandos_end;

635

759

}

636

760

637

761

const char *out = mandos_protocol_version;

641

765

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

642

766

out_size - written));

643

767

if(ret == -1){

644

perror("write");

645

retval = -1;

768

int e = errno;

769

perror_plus("write");

770

errno = e;

646

771

goto mandos_end;

647

772

}

648

773

written += (size_t)ret;

656

781

break;

657

782

}

658

783

}

784

785

if(quit_now){

786

errno = EINTR;

787

goto mandos_end;

788

}

659

789

}

660

790

661

791

if(debug){

662

792

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

663

793

}

664

794

795

if(quit_now){

796

errno = EINTR;

797

goto mandos_end;

798

}

799

800

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

665

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

666

802

667

do{

803

if(quit_now){

804

errno = EINTR;

805

goto mandos_end;

806

}

807

808

do {

668

809

ret = gnutls_handshake(session);

810

if(quit_now){

811

errno = EINTR;

812

goto mandos_end;

813

}

669

814

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

670

815

671

816

if(ret != GNUTLS_E_SUCCESS){

673

818

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

674

819

gnutls_perror(ret);

675

820

}

676

retval = -1;

821

errno = EPROTO;

677

822

goto mandos_end;

678

823

}

679

824

685

830

}

686

831

687

832

while(true){

688

buffer_capacity = adjustbuffer(&buffer, buffer_length,

833

834

if(quit_now){

835

errno = EINTR;

836

goto mandos_end;

837

}

838

839

buffer_capacity = incbuffer(&buffer, buffer_length,

689

840

buffer_capacity);

690

841

if(buffer_capacity == 0){

691

perror("adjustbuffer");

692

retval = -1;

842

int e = errno;

843

perror_plus("incbuffer");

844

errno = e;

845

goto mandos_end;

846

}

847

848

if(quit_now){

849

errno = EINTR;

693

850

goto mandos_end;

694

851

}

695

852

704

861

case GNUTLS_E_AGAIN:

705

862

break;

706

863

case GNUTLS_E_REHANDSHAKE:

707

do{

864

do {

708

865

ret = gnutls_handshake(session);

866

867

if(quit_now){

868

errno = EINTR;

869

goto mandos_end;

870

}

709

871

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

710

872

if(ret < 0){

711

873

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

712

874

gnutls_perror(ret);

713

retval = -1;

875

errno = EPROTO;

714

876

goto mandos_end;

715

877

}

716

878

break;

717

879

default:

718

880

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

719

881

" encrypted session with Mandos server\n");

720

retval = -1;

721

882

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

errno = EIO;

722

884

goto mandos_end;

723

885

}

724

886

} else {

730

892

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

731

893

}

732

894

733

gnutls_bye(session, GNUTLS_SHUT_RDWR);

895

if(quit_now){

896

errno = EINTR;

897

goto mandos_end;

898

}

899

900

do {

901

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

902

if(quit_now){

903

errno = EINTR;

904

goto mandos_end;

905

}

906

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

734

907

735

908

if(buffer_length > 0){

736

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

909

ssize_t decrypted_buffer_size;

910

decrypted_buffer_size = pgp_packet_decrypt(buffer,

737

911

buffer_length,

738

912

&decrypted_buffer);

739

913

if(decrypted_buffer_size >= 0){

914

740

915

written = 0;

741

916

while(written < (size_t) decrypted_buffer_size){

917

if(quit_now){

918

errno = EINTR;

919

goto mandos_end;

920

}

921

742

922

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

743

923

(size_t)decrypted_buffer_size - written,

744

924

stdout);

745

925

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

926

int e = errno;

746

927

if(debug){

747

928

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

748

929

strerror(errno));

749

930

}

750

retval = -1;

751

break;

931

errno = e;

932

goto mandos_end;

752

933

}

753

934

written += (size_t)ret;

754

935

}

755

free(decrypted_buffer);

756

} else {

757

retval = -1;

936

retval = 0;

758

937

}

759

} else {

760

retval = -1;

761

938

}

762

939

763

940

/* Shutdown procedure */

764

941

765

942

mandos_end:

766

free(buffer);

767

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

768

if(ret == -1){

769

perror("close");

943

{

944

int e = errno;

945

free(decrypted_buffer);

946

free(buffer);

947

if(tcp_sd >= 0){

948

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

949

}

950

if(ret == -1){

951

if(e == 0){

952

e = errno;

953

}

954

perror_plus("close");

955

}

956

gnutls_deinit(session);

957

errno = e;

958

if(quit_now){

959

errno = EINTR;

960

retval = -1;

961

}

770

962

}

771

gnutls_deinit(session);

772

963

return retval;

773

964

}

774

965

785

976

AVAHI_GCC_UNUSED AvahiStringList *txt,

786

977

AVAHI_GCC_UNUSED AvahiLookupResultFlags

787

978

flags,

788

void* userdata){

789

mandos_context *mc = userdata;

979

AVAHI_GCC_UNUSED void* userdata){

790

980

assert(r);

791

981

792

982

/* Called whenever a service has been resolved successfully or

793

983

timed out */

794

984

985

if(quit_now){

986

return;

987

}

988

795

989

switch(event){

796

990

default:

797

991

case AVAHI_RESOLVER_FAILURE:

798

992

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

799

993

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

800

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

994

avahi_strerror(avahi_server_errno(mc.server)));

801

995

break;

802

996

803

997

case AVAHI_RESOLVER_FOUND:

809

1003

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

810

1004

ip, (intmax_t)interface, port);

811

1005

}

812

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

1006

int ret = start_mandos_communication(ip, port, interface,

813

1007

avahi_proto_to_af(proto));

814

1008

if(ret == 0){

815

avahi_simple_poll_quit(mc->simple_poll);

1009

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

816

1013

}

817

1014

}

818

1015

}

828

1025

const char *domain,

829

1026

AVAHI_GCC_UNUSED AvahiLookupResultFlags

830

1027

flags,

831

void* userdata){

832

mandos_context *mc = userdata;

1028

AVAHI_GCC_UNUSED void* userdata){

833

1029

assert(b);

834

1030

835

1031

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

836

1032

is removed from the LAN */

837

1033

1034

if(quit_now){

1035

return;

1036

}

1037

838

1038

switch(event){

839

1039

default:

840

1040

case AVAHI_BROWSER_FAILURE:

841

1041

842

1042

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

843

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

844

avahi_simple_poll_quit(mc->simple_poll);

1043

avahi_strerror(avahi_server_errno(mc.server)));

1044

avahi_simple_poll_quit(mc.simple_poll);

845

1045

return;

846

1046

847

1047

case AVAHI_BROWSER_NEW:

850

1050

the callback function is called the Avahi server will free the

851

1051

resolver for us. */

852

1052

853

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

854

protocol, name, type, domain,

855

AVAHI_PROTO_INET6, 0,

856

resolve_callback, mc)))

1053

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

1054

name, type, domain, protocol, 0,

1055

resolve_callback, NULL) == NULL)

857

1056

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

858

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

1057

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

859

1058

break;

860

1059

861

1060

case AVAHI_BROWSER_REMOVE:

870

1069

}

871

1070

}

872

1071

1072

/* Signal handler that stops main loop after sigterm has been called */

1073

static void handle_sigterm(int sig){

1074

if(quit_now){

1075

return;

1076

}

1077

quit_now = 1;

1078

signal_received = sig;

1079

int old_errno = errno;

1080

/* set main loop to exit */

1081

if(mc.simple_poll != NULL){

1082

avahi_simple_poll_quit(mc.simple_poll);

1083

}

1084

errno = old_errno;

1085

}

1086

1087

/*

1088

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

1089

* corresponds to an acceptable network device.

1090

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

1091

*/

1092

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1188

}

1189

return 1;

1190

}

1191

1192

int notdotentries(const struct dirent *direntry){

1193

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

1194

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

1195

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

1196

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

1197

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

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1204

int ret;

1205

struct timespec now;

1206

struct timespec waited_time;

1207

intmax_t block_time;

1208

1209

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

fprintf(stderr, "Wait until first server is found. No timeout!\n");

1213

}

1214

ret = avahi_simple_poll_iterate(s, -1);

1215

} else {

1216

if (debug){

1217

fprintf(stderr, "Check current_server if we should run it, or wait\n");

1218

}

1219

/* the current time */

1220

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1221

if(ret == -1){

1222

perror_plus("clock_gettime");

1223

return -1;

1224

}

1225

/* Calculating in ms how long time between now and server

1226

who we visted longest time ago. Now - last seen. */

1227

waited_time.tv_sec = now.tv_sec - mc.current_server->last_seen.tv_sec;

1228

waited_time.tv_nsec = now.tv_nsec - mc.current_server->last_seen.tv_nsec;

1229

/* total time is 10s/10000ms. Converting to s to ms by 1000/s, and ns to ms by divind by 1000000. */

1230

block_time = (retry_interval - ((intmax_t)waited_time.tv_sec * 1000)) - ((intmax_t)waited_time.tv_nsec / 1000000);

1231

1232

if (debug){

1233

fprintf(stderr, "Blocking for %ld ms\n", block_time);

1234

}

1235

1236

if(block_time <= 0){

1237

ret = start_mandos_communication(mc.current_server->ip,

1238

mc.current_server->port,

1239

mc.current_server->if_index,

1240

mc.current_server->af);

1241

if(ret == 0){

1242

avahi_simple_poll_quit(mc.simple_poll);

1243

return 0;

1244

}

1245

ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);

1246

if(ret == -1){

1247

perror_plus("clock_gettime");

1248

return -1;

1249

}

1250

mc.current_server = mc.current_server->next;

1251

block_time = 0; /* call avahi to find new mandos servers, but dont block */

1252

}

1253

1254

ret = avahi_simple_poll_iterate(s, (int)block_time);

1255

}

1256

if(ret != 0){

1257

if (ret > 0 or errno != EINTR) {

1258

return (ret != 1) ? ret : 0;

1259

}

1260

}

1261

}

1262

}

1263

873

1264

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

874

1265

AvahiSServiceBrowser *sb = NULL;

875

1266

int error;

876

1267

int ret;

877

1268

intmax_t tmpmax;

878

int numchars;

1269

char *tmp;

879

1270

int exitcode = EXIT_SUCCESS;

880

const char *interface = "eth0";

1271

const char *interface = "";

881

1272

struct ifreq network;

882

int sd;

1273

int sd = -1;

1274

bool take_down_interface = false;

883

1275

uid_t uid;

884

1276

gid_t gid;

885

char *connect_to = NULL;

886

1277

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

887

1278

bool tempdir_created = false;

888

1279

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

889

1280

const char *seckey = PATHDIR "/" SECKEY;

890

1281

const char *pubkey = PATHDIR "/" PUBKEY;

891

1282

892

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

893

.dh_bits = 1024, .priority = "SECURE256"

894

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

895

1283

bool gnutls_initialized = false;

896

1284

bool gpgme_initialized = false;

897

double delay = 2.5;

1285

float delay = 2.5f;

1286

double retry_interval = 10; /* 10s between retrying a server and checking again*/

1287

1288

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1289

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1290

1291

uid = getuid();

1292

gid = getgid();

1293

1294

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

1295

errno = 0;

1296

ret = setgid(gid);

1297

if(ret == -1){

1298

perror_plus("setgid");

1299

}

1300

1301

/* Lower user privileges (temporarily) */

1302

errno = 0;

1303

ret = seteuid(uid);

1304

if(ret == -1){

1305

perror_plus("seteuid");

1306

}

1307

1308

if(quit_now){

1309

goto end;

1310

}

898

1311

899

1312

{

900

1313

struct argp_option options[] = {

930

1343

.arg = "SECONDS",

931

1344

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

932

1345

.group = 2 },

1346

{ .name = "retry", .key = 132,

1347

.arg = "SECONDS",

1348

.doc = "Retry interval used when denied by the mandos server",

1349

.group = 2 },

1350

/*

1351

* These reproduce what we would get without ARGP_NO_HELP

1352

*/

1353

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

1354

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

1355

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

1356

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

1357

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

1358

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

933

1359

{ .name = NULL }

934

1360

};

935

1361

936

1362

error_t parse_opt(int key, char *arg,

937

1363

struct argp_state *state){

1364

errno = 0;

938

1365

switch(key){

939

1366

case 128: /* --debug */

940

1367

debug = true;

952

1379

pubkey = arg;

953

1380

break;

954

1381

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

955

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

956

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

957

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

958

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

959

exit(EXIT_FAILURE);

1382

errno = 0;

1383

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

1384

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

1385

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

1386

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

960

1387

}

961

1388

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

962

1389

break;

964

1391

mc.priority = arg;

965

1392

break;

966

1393

case 131: /* --delay */

967

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

968

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

969

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

970

exit(EXIT_FAILURE);

1394

errno = 0;

1395

delay = strtof(arg, &tmp);

1396

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

1397

argp_error(state, "Bad delay");

1398

}

1399

case 132: /* --retry */

1400

errno = 0;

1401

retry_interval = strtod(arg, &tmp);

1402

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

1403

or (retry_interval * 1000) > INT_MAX){

1404

argp_error(state, "Bad retry interval");

971

1405

}

972

1406

break;

973

case ARGP_KEY_ARG:

974

argp_usage(state);

975

case ARGP_KEY_END:

1407

/*

1408

* These reproduce what we would get without ARGP_NO_HELP

1409

*/

1410

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

1411

argp_state_help(state, state->out_stream,

1412

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1413

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1414

case -3: /* --usage */

1415

argp_state_help(state, state->out_stream,

1416

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1417

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

1418

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

1419

exit(argp_err_exit_status);

976

1420

break;

977

1421

default:

978

1422

return ARGP_ERR_UNKNOWN;

979

1423

}

980

return 0;

1424

return errno;

981

1425

}

982

1426

983

1427

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

984

1428

.args_doc = "",

985

1429

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

986

1430

" passwords from a Mandos server" };

987

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

988

if(ret == ARGP_ERR_UNKNOWN){

989

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

1431

ret = argp_parse(&argp, argc, argv,

1432

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1433

switch(ret){

1434

case 0:

1435

break;

1436

case ENOMEM:

1437

default:

1438

errno = ret;

1439

perror_plus("argp_parse");

1440

exitcode = EX_OSERR;

1441

goto end;

1442

case EINVAL:

1443

exitcode = EX_USAGE;

1444

goto end;

1445

}

1446

}

1447

1448

if(not debug){

1449

avahi_set_log_function(empty_log);

1450

}

1451

1452

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

1453

struct dirent **direntries;

1454

ret = scandir(sys_class_net, &direntries, good_interface,

1455

alphasort);

1456

if(ret >= 1){

1457

/* Pick the first good interface */

1458

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

1459

if(debug){

1460

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

1461

}

1462

if(interface == NULL){

1463

perror_plus("malloc");

1464

free(direntries);

1465

exitcode = EXIT_FAILURE;

1466

goto end;

1467

}

1468

free(direntries);

1469

} else {

1470

free(direntries);

1471

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

990

1472

exitcode = EXIT_FAILURE;

991

1473

goto end;

992

1474

}

993

1475

}

994

1476

1477

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

1478

from the signal handler */

1479

/* Initialize the pseudo-RNG for Avahi */

1480

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

1481

mc.simple_poll = avahi_simple_poll_new();

1482

if(mc.simple_poll == NULL){

1483

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

1484

exitcode = EX_UNAVAILABLE;

1485

goto end;

1486

}

1487

1488

sigemptyset(&sigterm_action.sa_mask);

1489

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

1490

if(ret == -1){

1491

perror_plus("sigaddset");

1492

exitcode = EX_OSERR;

1493

goto end;

1494

}

1495

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

1496

if(ret == -1){

1497

perror_plus("sigaddset");

1498

exitcode = EX_OSERR;

1499

goto end;

1500

}

1501

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

1502

if(ret == -1){

1503

perror_plus("sigaddset");

1504

exitcode = EX_OSERR;

1505

goto end;

1506

}

1507

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

1508

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

1509

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

1510

*/

1511

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

1512

if(ret == -1){

1513

perror_plus("sigaction");

1514

return EX_OSERR;

1515

}

1516

if(old_sigterm_action.sa_handler != SIG_IGN){

1517

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

1518

if(ret == -1){

1519

perror_plus("sigaction");

1520

exitcode = EX_OSERR;

1521

goto end;

1522

}

1523

}

1524

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

1525

if(ret == -1){

1526

perror_plus("sigaction");

1527

return EX_OSERR;

1528

}

1529

if(old_sigterm_action.sa_handler != SIG_IGN){

1530

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

1531

if(ret == -1){

1532

perror_plus("sigaction");

1533

exitcode = EX_OSERR;

1534

goto end;

1535

}

1536

}

1537

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

1538

if(ret == -1){

1539

perror_plus("sigaction");

1540

return EX_OSERR;

1541

}

1542

if(old_sigterm_action.sa_handler != SIG_IGN){

1543

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

1544

if(ret == -1){

1545

perror_plus("sigaction");

1546

exitcode = EX_OSERR;

1547

goto end;

1548

}

1549

}

1550

995

1551

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

996

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

1552

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

1553

if_index = (AvahiIfIndex) if_nametoindex(interface);

1554

if(if_index == 0){

1555

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

1556

exitcode = EX_UNAVAILABLE;

1557

goto end;

1558

}

1559

1560

if(quit_now){

1561

goto end;

1562

}

1563

1564

/* Re-raise priviliges */

1565

errno = 0;

1566

ret = seteuid(0);

1567

if(ret == -1){

1568

perror_plus("seteuid");

1569

}

1570

997

1571

#ifdef __linux__

998

1572

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

999

messages to mess up the prompt */

1573

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

1000

1574

ret = klogctl(8, NULL, 5);

1001

1575

bool restore_loglevel = true;

1002

1576

if(ret == -1){

1003

1577

restore_loglevel = false;

1004

perror("klogctl");

1578

perror_plus("klogctl");

1005

1579

}

1006

#endif

1580

#endif /* __linux__ */

1007

1581

1008

1582

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1009

1583

if(sd < 0){

1010

perror("socket");

1011

exitcode = EXIT_FAILURE;

1584

perror_plus("socket");

1585

exitcode = EX_OSERR;

1012

1586

#ifdef __linux__

1013

1587

if(restore_loglevel){

1014

1588

ret = klogctl(7, NULL, 0);

1015

1589

if(ret == -1){

1016

perror("klogctl");

1590

perror_plus("klogctl");

1017

1591

}

1018

1592

}

1019

#endif

1593

#endif /* __linux__ */

1594

/* Lower privileges */

1595

errno = 0;

1596

ret = seteuid(uid);

1597

if(ret == -1){

1598

perror_plus("seteuid");

1599

}

1020

1600

goto end;

1021

1601

}

1022

1602

strcpy(network.ifr_name, interface);

1023

1603

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

1024

1604

if(ret == -1){

1025

perror("ioctl SIOCGIFFLAGS");

1605

perror_plus("ioctl SIOCGIFFLAGS");

1026

1606

#ifdef __linux__

1027

1607

if(restore_loglevel){

1028

1608

ret = klogctl(7, NULL, 0);

1029

1609

if(ret == -1){

1030

perror("klogctl");

1610

perror_plus("klogctl");

1031

1611

}

1032

1612

}

1033

#endif

1034

exitcode = EXIT_FAILURE;

1613

#endif /* __linux__ */

1614

exitcode = EX_OSERR;

1615

/* Lower privileges */

1616

errno = 0;

1617

ret = seteuid(uid);

1618

if(ret == -1){

1619

perror_plus("seteuid");

1620

}

1035

1621

goto end;

1036

1622

}

1037

1623

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

1038

1624

network.ifr_flags |= IFF_UP;

1625

take_down_interface = true;

1039

1626

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

1040

1627

if(ret == -1){

1041

perror("ioctl SIOCSIFFLAGS");

1042

exitcode = EXIT_FAILURE;

1628

take_down_interface = false;

1629

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1630

exitcode = EX_OSERR;

1043

1631

#ifdef __linux__

1044

1632

if(restore_loglevel){

1045

1633

ret = klogctl(7, NULL, 0);

1046

1634

if(ret == -1){

1047

perror("klogctl");

1635

perror_plus("klogctl");

1048

1636

}

1049

1637

}

1050

#endif

1638

#endif /* __linux__ */

1639

/* Lower privileges */

1640

errno = 0;

1641

ret = seteuid(uid);

1642

if(ret == -1){

1643

perror_plus("seteuid");

1644

}

1051

1645

goto end;

1052

1646

}

1053

1647

}

1054

/* sleep checking until interface is running */

1648

/* sleep checking until interface is running. Check every 0.25s, up to total time of delay */

1055

1649

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

1056

1650

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

1057

1651

if(ret == -1){

1058

perror("ioctl SIOCGIFFLAGS");

1652

perror_plus("ioctl SIOCGIFFLAGS");

1059

1653

} else if(network.ifr_flags & IFF_RUNNING){

1060

1654

break;

1061

1655

}

1062

1656

struct timespec sleeptime = { .tv_nsec = 250000000 };

1063

1657

ret = nanosleep(&sleeptime, NULL);

1064

1658

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

1065

perror("nanosleep");

1659

perror_plus("nanosleep");

1066

1660

}

1067

1661

}

1068

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

1069

if(ret == -1){

1070

perror("close");

1662

if(not take_down_interface){

1663

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

1664

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

1665

if(ret == -1){

1666

perror_plus("close");

1667

}

1071

1668

}

1072

1669

#ifdef __linux__

1073

1670

if(restore_loglevel){

1074

1671

/* Restores kernel loglevel to default */

1075

1672

ret = klogctl(7, NULL, 0);

1076

1673

if(ret == -1){

1077

perror("klogctl");

1078

}

1079

}

1080

#endif

1081

}

1082

1083

uid = getuid();

1084

gid = getgid();

1085

1086

errno = 0;

1087

setgid(gid);

1088

if(ret == -1){

1089

perror("setgid");

1090

}

1091

1092

ret = setuid(uid);

1093

if(ret == -1){

1094

perror("setuid");

1095

}

1096

1097

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

1674

perror_plus("klogctl");

1675

}

1676

}

1677

#endif /* __linux__ */

1678

/* Lower privileges */

1679

errno = 0;

1680

if(take_down_interface){

1681

/* Lower privileges */

1682

ret = seteuid(uid);

1683

if(ret == -1){

1684

perror_plus("seteuid");

1685

}

1686

} else {

1687

/* Lower privileges permanently */

1688

ret = setuid(uid);

1689

if(ret == -1){

1690

perror_plus("setuid");

1691

}

1692

}

1693

}

1694

1695

if(quit_now){

1696

goto end;

1697

}

1698

1699

ret = init_gnutls_global(pubkey, seckey);

1098

1700

if(ret == -1){

1099

1701

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

1100

exitcode = EXIT_FAILURE;

1702

exitcode = EX_UNAVAILABLE;

1101

1703

goto end;

1102

1704

} else {

1103

1705

gnutls_initialized = true;

1104

1706

}

1105

1707

1708

if(quit_now){

1709

goto end;

1710

}

1711

1106

1712

if(mkdtemp(tempdir) == NULL){

1107

perror("mkdtemp");

1713

perror_plus("mkdtemp");

1108

1714

goto end;

1109

1715

}

1110

1716

tempdir_created = true;

1111

1717

1112

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

1718

if(quit_now){

1719

goto end;

1720

}

1721

1722

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

1113

1723

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

1114

exitcode = EXIT_FAILURE;

1724

exitcode = EX_UNAVAILABLE;

1115

1725

goto end;

1116

1726

} else {

1117

1727

gpgme_initialized = true;

1118

1728

}

1119

1729

1120

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

1121

if_index = (AvahiIfIndex) if_nametoindex(interface);

1122

if(if_index == 0){

1123

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

1124

exitcode = EXIT_FAILURE;

1125

goto end;

1126

}

1730

if(quit_now){

1731

goto end;

1127

1732

}

1128

1733

1129

1734

if(connect_to != NULL){

1132

1737

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

1133

1738

if(address == NULL){

1134

1739

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

1135

exitcode = EXIT_FAILURE;

1136

goto end;

1137

}

1740

exitcode = EX_USAGE;

1741

goto end;

1742

}

1743

1744

if(quit_now){

1745

goto end;

1746

}

1747

1138

1748

uint16_t port;

1139

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

1140

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

1141

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

1749

errno = 0;

1750

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

1751

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

1752

or tmpmax != (uint16_t)tmpmax){

1142

1753

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

1143

exitcode = EXIT_FAILURE;

1144

goto end;

1145

}

1754

exitcode = EX_USAGE;

1755

goto end;

1756

}

1757

1758

if(quit_now){

1759

goto end;

1760

}

1761

1146

1762

port = (uint16_t)tmpmax;

1147

1763

*address = '\0';

1148

1764

address = connect_to;

1153

1769

} else {

1154

1770

af = AF_INET;

1155

1771

}

1156

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

1157

af);

1158

if(ret < 0){

1159

exitcode = EXIT_FAILURE;

1160

} else {

1772

1773

if(quit_now){

1774

goto end;

1775

}

1776

1777

while(not quit_now){

1778

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

1779

if(quit_now or ret == 0){

1780

break;

1781

}

1782

sleep((int)retry_interval or 1);

1783

};

1784

1785

if (not quit_now){

1161

1786

exitcode = EXIT_SUCCESS;

1162

1787

}

1788

1163

1789

goto end;

1164

1790

}

1165

1791

1166

if(not debug){

1167

avahi_set_log_function(empty_log);

1168

}

1169

1170

/* Initialize the pseudo-RNG for Avahi */

1171

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

1172

1173

/* Allocate main Avahi loop object */

1174

mc.simple_poll = avahi_simple_poll_new();

1175

if(mc.simple_poll == NULL){

1176

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

1177

exitcode = EXIT_FAILURE;

1792

if(quit_now){

1178

1793

goto end;

1179

1794

}

1180

1795

1200

1815

if(mc.server == NULL){

1201

1816

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

1202

1817

avahi_strerror(error));

1203

exitcode = EXIT_FAILURE;

1818

exitcode = EX_UNAVAILABLE;

1819

goto end;

1820

}

1821

1822

if(quit_now){

1204

1823

goto end;

1205

1824

}

1206

1825

1207

1826

/* Create the Avahi service browser */

1208

1827

sb = avahi_s_service_browser_new(mc.server, if_index,

1209

AVAHI_PROTO_INET6, "_mandos._tcp",

1210

NULL, 0, browse_callback, &mc);

1828

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1829

NULL, 0, browse_callback, NULL);

1211

1830

if(sb == NULL){

1212

1831

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

1213

1832

avahi_strerror(avahi_server_errno(mc.server)));

1214

exitcode = EXIT_FAILURE;

1833

exitcode = EX_UNAVAILABLE;

1834

goto end;

1835

}

1836

1837

if(quit_now){

1215

1838

goto end;

1216

1839

}

1217

1840

1220

1843

if(debug){

1221

1844

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

1222

1845

}

1223

1224

avahi_simple_poll_loop(mc.simple_poll);

1846

1847

ret = avahi_loop_with_timeout(mc.simple_poll, (int)(retry_interval * 1000));

1848

if(debug){

1849

fprintf(stderr, "avahi_loop_with_timeout exited %s\n",

1850

(ret == 0) ? "successfully" : "with error");

1851

}

1225

1852

1226

1853

end:

1227

1854

1248

1875

if(gpgme_initialized){

1249

1876

gpgme_release(mc.ctx);

1250

1877

}

1251

1252

/* Removes the temp directory used by GPGME */

1878

1879

/* cleans up the circular linked list of mandos servers the client has seen */

1880

if(mc.current_server != NULL){

1881

mc.current_server->prev->next = NULL;

1882

while(mc.current_server != NULL){

1883

server *next = mc.current_server->next;

1884

free(mc.current_server);

1885

mc.current_server = next;

1886

}

1887

}

1888

1889

/* Take down the network interface */

1890

if(take_down_interface){

1891

/* Re-raise priviliges */

1892

errno = 0;

1893

ret = seteuid(0);

1894

if(ret == -1){

1895

perror_plus("seteuid");

1896

}

1897

if(geteuid() == 0){

1898

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

1899

if(ret == -1){

1900

perror_plus("ioctl SIOCGIFFLAGS");

1901

} else if(network.ifr_flags & IFF_UP) {

1902

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

1903

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

1904

if(ret == -1){

1905

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1906

}

1907

}

1908

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

1909

if(ret == -1){

1910

perror_plus("close");

1911

}

1912

/* Lower privileges permanently */

1913

errno = 0;

1914

ret = setuid(uid);

1915

if(ret == -1){

1916

perror_plus("setuid");

1917

}

1918

}

1919

}

1920

1921

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

1253

1922

if(tempdir_created){

1254

DIR *d;

1255

struct dirent *direntry;

1256

d = opendir(tempdir);

1257

if(d == NULL){

1258

if(errno != ENOENT){

1259

perror("opendir");

1260

}

1261

} else {

1262

while(true){

1263

direntry = readdir(d);

1264

if(direntry == NULL){

1265

break;

1266

}

1267

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

1268

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

1269

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

1270

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

1271

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

1272

continue;

1273

}

1923

struct dirent **direntries = NULL;

1924

struct dirent *direntry = NULL;

1925

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

1926

if (ret > 0){

1927

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

1928

direntry = direntries[i];

1274

1929

char *fullname = NULL;

1275

1930

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

1276

1931

direntry->d_name);

1277

1932

if(ret < 0){

1278

perror("asprintf");

1933

perror_plus("asprintf");

1279

1934

continue;

1280

1935

}

1281

1936

ret = remove(fullname);

1285

1940

}

1286

1941

free(fullname);

1287

1942

}

1288

closedir(d);

1943

}

1944

1945

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

1946

free(direntries);

1947

if (ret == -1){

1948

perror_plus("scandir");

1289

1949

}

1290

1950

ret = rmdir(tempdir);

1291

1951

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

1292

perror("rmdir");

1293

}

1952

perror_plus("rmdir");

1953

}

1954

}

1955

1956

if(quit_now){

1957

sigemptyset(&old_sigterm_action.sa_mask);

1958

old_sigterm_action.sa_handler = SIG_DFL;

1959

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1960

&old_sigterm_action,

1961

NULL));

1962

if(ret == -1){

1963

perror_plus("sigaction");

1964

}

1965

do {

1966

ret = raise(signal_received);

1967

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

1968

if(ret != 0){

1969

perror_plus("raise");

1970

abort();

1971

}

1972

TEMP_FAILURE_RETRY(pause());

1294

1973

}

1295

1974

1296

1975

return exitcode;