/mandos/release : revision 237.7.486

9

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

10

*

11

* Everything else is

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

17

* published by the Free Software Foundation, either version 3 of the

18

* License, or (at your option) any later version.

19

*

20

* This program is distributed in the hope that it will be useful, but

12

13

14

*

15

* This file is part of Mandos.

16

*

17

* Mandos is free software: you can redistribute it and/or modify it

18

* under the terms of the GNU General Public License as published by

19

* the Free Software Foundation, either version 3 of the License, or

20

* (at your option) any later version.

21

*

22

* Mandos is distributed in the hope that it will be useful, but

21

23

* WITHOUT ANY WARRANTY; without even the implied warranty of

22

24

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

23

25

* General Public License for more details.

24

26

*

25

27

* You should have received a copy of the GNU General Public License

26

* along with this program. If not, see

27

* <http://www.gnu.org/licenses/>.

28

* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

28

29

*

29

30

* Contact the authors at <mandos@recompile.se>.

30

31

*/

32

33

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

33

34

#ifndef _LARGEFILE_SOURCE

34

35

#define _LARGEFILE_SOURCE

35

#endif

36

#endif /* not _LARGEFILE_SOURCE */

36

37

#ifndef _FILE_OFFSET_BITS

37

38

#define _FILE_OFFSET_BITS 64

38

#endif

39

#endif /* not _FILE_OFFSET_BITS */

39

40

41

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

41

42

43

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

43

stdout, ferror(), remove() */

44

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

44

stdout, ferror() */

45

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

45

46

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

46

47

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

47

48

strtof(), abort() */

48

49

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

49

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

50

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

50

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

51

asprintf(), strncpy(), strsignal()

52

*/

51

53

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

52

54

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

53

55

sockaddr_in6, PF_INET6,

55

57

opendir(), DIR */

56

58

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

57

59

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

58

inet_pton(), connect() */

59

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

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

60

63

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

61

64

*/

62

65

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

63

66

strtoimax() */

64

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

65

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

67

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

68

EAI_SYSTEM, ENETUNREACH,

69

EHOSTUNREACH, ECONNREFUSED, EPROTO,

70

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

71

ENOTEMPTY,

66

72

program_invocation_short_name */

67

73

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

68

74

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

73

79

*/

74

80

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

75

81

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

76

setgid(), pause() */

77

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

82

setgid(), pause(), _exit(),

83

unlinkat() */

84

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

78

85

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

79

86

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

80

87

argp_state, struct argp,

87

94

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

95

#include <sys/wait.h> /* waitpid(), WIFEXITED(),

89

96

WEXITSTATUS(), WTERMSIG() */

97

#include <grp.h> /* setgroups() */

98

#include <argz.h> /* argz_add_sep(), argz_next(),

99

argz_delete(), argz_append(),

100

argz_stringify(), argz_add(),

101

argz_count() */

102

#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,

103

EAI_SYSTEM, gai_strerror() */

90

104

91

105

#ifdef __linux__

92

106

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

134

148

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

135

149

char *connect_to = NULL;

136

150

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

152

uid_t uid = 65534;

153

gid_t gid = 65534;

137

154

138

155

/* Doubly linked list that need to be circularly linked when used */

139

156

typedef struct server{

140

157

const char *ip;

141

uint16_t port;

158

in_port_t port;

142

159

AvahiIfIndex if_index;

143

160

int af;

144

161

struct timespec last_seen;

148

165

149

166

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

150

167

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

168

AvahiServer *server;

153

169

gnutls_certificate_credentials_t cred;

154

170

unsigned int dh_bits;

156

172

const char *priority;

157

173

gpgme_ctx_t ctx;

158

174

server *current_server;

175

char *interfaces;

176

size_t interfaces_size;

159

177

} mandos_context;

160

178

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

":!CTYPE-X.509:+CTYPE-OPENPGP",

165

.current_server = NULL };

179

/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

166

181

167

182

sig_atomic_t quit_now = 0;

168

183

int signal_received = 0;

169

184

170

185

/* Function to use when printing errors */

171

186

void perror_plus(const char *print_text){

187

int e = errno;

172

188

fprintf(stderr, "Mandos plugin %s: ",

173

189

program_invocation_short_name);

190

errno = e;

174

191

perror(print_text);

175

192

}

176

193

194

__attribute__((format (gnu_printf, 2, 3), nonnull))

177

195

int fprintf_plus(FILE *stream, const char *format, ...){

178

196

va_list ap;

179

197

va_start (ap, format);

180

198

181

199

TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",

182

200

program_invocation_short_name));

183

return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

201

return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

184

202

}

185

203

186

204

/*

188

206

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

189

207

* "buffer_length" is how much is already used.

190

208

*/

209

__attribute__((nonnull, warn_unused_result))

191

210

size_t incbuffer(char **buffer, size_t buffer_length,

192

211

size_t buffer_capacity){

193

212

if(buffer_length + BUFFER_SIZE > buffer_capacity){

194

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

195

if(buffer == NULL){

213

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

214

if(new_buf == NULL){

215

int old_errno = errno;

216

free(*buffer);

217

errno = old_errno;

218

*buffer = NULL;

196

219

return 0;

197

220

}

221

*buffer = new_buf;

198

222

buffer_capacity += BUFFER_SIZE;

199

223

}

200

224

return buffer_capacity;

201

225

}

202

226

203

227

/* Add server to set of servers to retry periodically */

204

int add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,

205

int af){

228

__attribute__((nonnull, warn_unused_result))

229

bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,

230

int af, server **current_server){

206

231

int ret;

207

232

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

208

233

if(new_server == NULL){

209

234

perror_plus("malloc");

210

return -1;

235

return false;

211

236

}

212

237

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

213

238

.port = port,

215

240

.af = af };

216

241

if(new_server->ip == NULL){

217

242

perror_plus("strdup");

218

return -1;

243

free(new_server);

244

return false;

245

}

246

ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

free((char *)(new_server->ip));

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

return false;

219

259

}

220

260

/* Special case of first server */

221

if (mc.current_server == NULL){

261

if(*current_server == NULL){

222

262

new_server->next = new_server;

223

263

new_server->prev = new_server;

224

mc.current_server = new_server;

225

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

264

*current_server = new_server;

226

265

} else {

227

new_server->next = mc.current_server;

228

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

266

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

267

new_server->next = *current_server;

268

new_server->prev = (*current_server)->prev;

229

269

new_server->prev->next = new_server;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

270

(*current_server)->prev = new_server;

271

}

272

return true;

238

273

}

239

274

240

275

/*

241

276

* Initialize GPGME.

242

277

*/

243

static bool init_gpgme(const char *seckey, const char *pubkey,

244

const char *tempdir){

278

__attribute__((nonnull, warn_unused_result))

279

static bool init_gpgme(const char * const seckey,

280

const char * const pubkey,

281

const char * const tempdir,

282

mandos_context *mc){

245

283

gpgme_error_t rc;

246

284

gpgme_engine_info_t engine_info;

247

285

248

249

286

/*

250

287

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

251

288

*/

252

bool import_key(const char *filename){

289

bool import_key(const char * const filename){

253

290

int ret;

254

291

int fd;

255

292

gpgme_data_t pgp_data;

267

304

return false;

268

305

}

269

306

270

rc = gpgme_op_import(mc.ctx, pgp_data);

307

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

271

308

if(rc != GPG_ERR_NO_ERROR){

272

309

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

273

310

gpgme_strsource(rc), gpgme_strerror(rc));

274

311

return false;

275

312

}

276

313

277

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

314

ret = close(fd);

278

315

if(ret == -1){

279

316

perror_plus("close");

280

317

}

317

354

}

318

355

319

356

/* Create new GPGME "context" */

320

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

357

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

321

358

if(rc != GPG_ERR_NO_ERROR){

322

359

fprintf_plus(stderr, "Mandos plugin mandos-client: "

323

360

"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),

336

373

* Decrypt OpenPGP data.

337

374

* Returns -1 on error

338

375

*/

376

__attribute__((nonnull, warn_unused_result))

339

377

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

378

size_t crypto_size,

341

char **plaintext){

379

char **plaintext,

380

mandos_context *mc){

342

381

gpgme_data_t dh_crypto, dh_plain;

343

382

gpgme_error_t rc;

344

383

ssize_t ret;

370

409

371

410

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

372

411

data buffer */

373

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

412

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

374

413

if(rc != GPG_ERR_NO_ERROR){

375

414

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

376

415

gpgme_strsource(rc), gpgme_strerror(rc));

377

416

plaintext_length = -1;

378

417

if(debug){

379

418

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

419

result = gpgme_op_decrypt_result(mc->ctx);

381

420

if(result == NULL){

382

421

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

383

422

} else {

460

499

return plaintext_length;

461

500

}

462

501

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

466

if(ret == NULL)

467

ret = "(unknown)";

468

return ret;

502

__attribute__((warn_unused_result, const))

503

static const char *safe_string(const char *str){

504

if(str == NULL)

505

return "(unknown)";

506

return str;

507

}

508

509

__attribute__((warn_unused_result))

510

static const char *safer_gnutls_strerror(int value){

511

const char *ret = gnutls_strerror(value);

512

return safe_string(ret);

469

513

}

470

514

471

515

/* GnuTLS log function callback */

516

__attribute__((nonnull))

472

517

static void debuggnutls(__attribute__((unused)) int level,

473

518

const char* string){

474

519

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

475

520

}

476

521

522

__attribute__((nonnull(1, 2, 4), warn_unused_result))

477

523

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

526

mandos_context *mc){

479

527

int ret;

528

unsigned int uret;

480

529

481

530

if(debug){

482

531

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

483

532

}

484

533

485

ret = gnutls_global_init();

486

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

489

return -1;

490

}

491

492

534

if(debug){

493

535

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

494

536

* - GnuTLS manual

498

540

}

499

541

500

542

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

544

if(ret != GNUTLS_E_SUCCESS){

503

545

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

504

546

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

506

547

return -1;

507

548

}

508

549

514

555

}

515

556

516

557

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

558

(mc->cred, pubkeyfilename, seckeyfilename,

518

559

GNUTLS_OPENPGP_FMT_BASE64);

519

560

if(ret != GNUTLS_E_SUCCESS){

520

561

fprintf_plus(stderr,

526

567

}

527

568

528

569

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

570

ret = gnutls_dh_params_init(&mc->dh_params);

530

571

if(ret != GNUTLS_E_SUCCESS){

531

572

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

573

" initialization: %s\n",

533

574

safer_gnutls_strerror(ret));

534

575

goto globalfail;

535

576

}

536

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

537

if(ret != GNUTLS_E_SUCCESS){

538

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

539

safer_gnutls_strerror(ret));

540

goto globalfail;

541

}

542

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

577

/* If a Diffie-Hellman parameters file was given, try to use it */

578

if(dhparamsfilename != NULL){

579

gnutls_datum_t params = { .data = NULL, .size = 0 };

580

do {

581

int dhpfile = open(dhparamsfilename, O_RDONLY);

582

if(dhpfile == -1){

583

perror_plus("open");

584

dhparamsfilename = NULL;

585

break;

586

}

587

size_t params_capacity = 0;

588

while(true){

589

params_capacity = incbuffer((char **)&params.data,

590

(size_t)params.size,

591

(size_t)params_capacity);

592

if(params_capacity == 0){

593

perror_plus("incbuffer");

594

free(params.data);

595

params.data = NULL;

596

dhparamsfilename = NULL;

597

break;

598

}

599

ssize_t bytes_read = read(dhpfile,

600

params.data + params.size,

601

BUFFER_SIZE);

602

/* EOF */

603

if(bytes_read == 0){

604

break;

605

}

606

/* check bytes_read for failure */

607

if(bytes_read < 0){

608

perror_plus("read");

609

free(params.data);

610

params.data = NULL;

611

dhparamsfilename = NULL;

612

break;

613

}

614

params.size += (unsigned int)bytes_read;

615

}

616

if(params.data == NULL){

617

dhparamsfilename = NULL;

618

}

619

if(dhparamsfilename == NULL){

620

break;

621

}

622

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

623

GNUTLS_X509_FMT_PEM);

624

if(ret != GNUTLS_E_SUCCESS){

625

fprintf_plus(stderr, "Failed to parse DH parameters in file"

626

" \"%s\": %s\n", dhparamsfilename,

627

safer_gnutls_strerror(ret));

628

dhparamsfilename = NULL;

629

}

630

free(params.data);

631

} while(false);

632

}

633

if(dhparamsfilename == NULL){

634

if(mc->dh_bits == 0){

635

/* Find out the optimal number of DH bits */

636

/* Try to read the private key file */

637

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

638

do {

639

int secfile = open(seckeyfilename, O_RDONLY);

640

if(secfile == -1){

641

perror_plus("open");

642

break;

643

}

644

size_t buffer_capacity = 0;

645

while(true){

646

buffer_capacity = incbuffer((char **)&buffer.data,

647

(size_t)buffer.size,

648

(size_t)buffer_capacity);

649

if(buffer_capacity == 0){

650

perror_plus("incbuffer");

651

free(buffer.data);

652

buffer.data = NULL;

653

break;

654

}

655

ssize_t bytes_read = read(secfile,

656

buffer.data + buffer.size,

657

BUFFER_SIZE);

658

/* EOF */

659

if(bytes_read == 0){

660

break;

661

}

662

/* check bytes_read for failure */

663

if(bytes_read < 0){

664

perror_plus("read");

665

free(buffer.data);

666

buffer.data = NULL;

667

break;

668

}

669

buffer.size += (unsigned int)bytes_read;

670

}

671

close(secfile);

672

} while(false);

673

/* If successful, use buffer to parse private key */

674

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

675

if(buffer.data != NULL){

676

{

677

gnutls_openpgp_privkey_t privkey = NULL;

678

ret = gnutls_openpgp_privkey_init(&privkey);

679

if(ret != GNUTLS_E_SUCCESS){

680

fprintf_plus(stderr, "Error initializing OpenPGP key"

681

" structure: %s",

682

safer_gnutls_strerror(ret));

683

free(buffer.data);

684

buffer.data = NULL;

685

} else {

686

ret = gnutls_openpgp_privkey_import

687

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

688

if(ret != GNUTLS_E_SUCCESS){

689

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

690

safer_gnutls_strerror(ret));

691

privkey = NULL;

692

}

693

free(buffer.data);

694

buffer.data = NULL;

695

if(privkey != NULL){

696

/* Use private key to suggest an appropriate

697

sec_param */

698

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

699

gnutls_openpgp_privkey_deinit(privkey);

700

if(debug){

701

fprintf_plus(stderr, "This OpenPGP key implies using"

702

" a GnuTLS security parameter \"%s\".\n",

703

safe_string(gnutls_sec_param_get_name

704

(sec_param)));

705

}

706

}

707

}

708

}

709

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

710

/* Err on the side of caution */

711

sec_param = GNUTLS_SEC_PARAM_ULTRA;

712

if(debug){

713

fprintf_plus(stderr, "Falling back to security parameter"

714

" \"%s\"\n",

715

safe_string(gnutls_sec_param_get_name

716

(sec_param)));

717

}

718

}

719

}

720

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

721

if(uret != 0){

722

mc->dh_bits = uret;

723

if(debug){

724

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

725

" implies %u DH bits; using that.\n",

726

safe_string(gnutls_sec_param_get_name

727

(sec_param)),

728

mc->dh_bits);

729

}

730

} else {

731

fprintf_plus(stderr, "Failed to get implied number of DH"

732

" bits for security parameter \"%s\"): %s\n",

733

safe_string(gnutls_sec_param_get_name

734

(sec_param)),

735

safer_gnutls_strerror(ret));

736

goto globalfail;

737

}

738

} else if(debug){

739

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

740

mc->dh_bits);

741

}

742

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

743

if(ret != GNUTLS_E_SUCCESS){

744

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"

745

" bits): %s\n", mc->dh_bits,

746

safer_gnutls_strerror(ret));

747

goto globalfail;

748

}

749

}

750

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

544

751

545

752

return 0;

546

753

547

754

globalfail:

548

755

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

756

gnutls_certificate_free_credentials(mc->cred);

757

gnutls_dh_params_deinit(mc->dh_params);

552

758

return -1;

553

759

}

554

760

555

static int init_gnutls_session(gnutls_session_t *session){

761

__attribute__((nonnull, warn_unused_result))

762

static int init_gnutls_session(gnutls_session_t *session,

763

mandos_context *mc){

556

764

int ret;

557

765

/* GnuTLS session creation */

558

766

do {

570

778

{

571

779

const char *err;

572

780

do {

573

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

781

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

574

782

if(quit_now){

575

783

gnutls_deinit(*session);

576

784

return -1;

587

795

588

796

do {

589

797

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

798

mc->cred);

591

799

if(quit_now){

592

800

gnutls_deinit(*session);

593

801

return -1;

603

811

/* ignore client certificate if any. */

604

812

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

813

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

814

return 0;

609

815

}

610

816

612

818

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

613

819

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

614

820

821

/* Set effective uid to 0, return errno */

822

__attribute__((warn_unused_result))

823

int raise_privileges(void){

824

int old_errno = errno;

825

int ret = 0;

826

if(seteuid(0) == -1){

827

ret = errno;

828

}

829

errno = old_errno;

830

return ret;

831

}

832

833

/* Set effective and real user ID to 0. Return errno. */

834

__attribute__((warn_unused_result))

835

int raise_privileges_permanently(void){

836

int old_errno = errno;

837

int ret = raise_privileges();

838

if(ret != 0){

839

errno = old_errno;

840

return ret;

841

}

842

if(setuid(0) == -1){

843

ret = errno;

844

}

845

errno = old_errno;

846

return ret;

847

}

848

849

/* Set effective user ID to unprivileged saved user ID */

850

__attribute__((warn_unused_result))

851

int lower_privileges(void){

852

int old_errno = errno;

853

int ret = 0;

854

if(seteuid(uid) == -1){

855

ret = errno;

856

}

857

errno = old_errno;

858

return ret;

859

}

860

861

/* Lower privileges permanently */

862

__attribute__((warn_unused_result))

863

int lower_privileges_permanently(void){

864

int old_errno = errno;

865

int ret = 0;

866

if(setuid(uid) == -1){

867

ret = errno;

868

}

869

errno = old_errno;

870

return ret;

871

}

872

873

/* Helper function to add_local_route() and delete_local_route() */

874

__attribute__((nonnull, warn_unused_result))

875

static bool add_delete_local_route(const bool add,

876

const char *address,

877

AvahiIfIndex if_index){

878

int ret;

879

char helper[] = "mandos-client-iprouteadddel";

880

char add_arg[] = "add";

881

char delete_arg[] = "delete";

882

char debug_flag[] = "--debug";

883

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

884

if(pluginhelperdir == NULL){

885

if(debug){

886

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

887

" variable not set; cannot run helper\n");

888

}

889

return false;

890

}

891

892

char interface[IF_NAMESIZE];

893

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

894

perror_plus("if_indextoname");

895

return false;

896

}

897

898

int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));

899

if(devnull == -1){

900

perror_plus("open(\"/dev/null\", O_RDONLY)");

901

return false;

902

}

903

pid_t pid = fork();

904

if(pid == 0){

905

/* Child */

906

/* Raise privileges */

907

errno = raise_privileges_permanently();

908

if(errno != 0){

909

perror_plus("Failed to raise privileges");

910

/* _exit(EX_NOPERM); */

911

} else {

912

/* Set group */

913

errno = 0;

914

ret = setgid(0);

915

if(ret == -1){

916

perror_plus("setgid");

917

_exit(EX_NOPERM);

918

}

919

/* Reset supplementary groups */

920

errno = 0;

921

ret = setgroups(0, NULL);

922

if(ret == -1){

923

perror_plus("setgroups");

924

_exit(EX_NOPERM);

925

}

926

}

927

ret = dup2(devnull, STDIN_FILENO);

928

if(ret == -1){

929

perror_plus("dup2(devnull, STDIN_FILENO)");

930

_exit(EX_OSERR);

931

}

932

ret = close(devnull);

933

if(ret == -1){

934

perror_plus("close");

935

_exit(EX_OSERR);

936

}

937

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

938

if(ret == -1){

939

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

940

_exit(EX_OSERR);

941

}

942

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

943

O_RDONLY

944

| O_DIRECTORY

945

| O_PATH

946

| O_CLOEXEC));

947

if(helperdir_fd == -1){

948

perror_plus("open");

949

_exit(EX_UNAVAILABLE);

950

}

951

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

952

helper, O_RDONLY));

953

if(helper_fd == -1){

954

perror_plus("openat");

955

close(helperdir_fd);

956

_exit(EX_UNAVAILABLE);

957

}

958

close(helperdir_fd);

959

#ifdef __GNUC__

960

#pragma GCC diagnostic push

961

#pragma GCC diagnostic ignored "-Wcast-qual"

962

#endif

963

if(fexecve(helper_fd, (char *const [])

964

{ helper, add ? add_arg : delete_arg, (char *)address,

965

interface, debug ? debug_flag : NULL, NULL },

966

environ) == -1){

967

#ifdef __GNUC__

968

#pragma GCC diagnostic pop

969

#endif

970

perror_plus("fexecve");

971

_exit(EXIT_FAILURE);

972

}

973

}

974

if(pid == -1){

975

perror_plus("fork");

976

return false;

977

}

978

int status;

979

pid_t pret = -1;

980

errno = 0;

981

do {

982

pret = waitpid(pid, &status, 0);

983

if(pret == -1 and errno == EINTR and quit_now){

984

int errno_raising = 0;

985

if((errno = raise_privileges()) != 0){

986

errno_raising = errno;

987

perror_plus("Failed to raise privileges in order to"

988

" kill helper program");

989

}

990

if(kill(pid, SIGTERM) == -1){

991

perror_plus("kill");

992

}

993

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

994

perror_plus("Failed to lower privileges after killing"

995

" helper program");

996

}

997

return false;

998

}

999

} while(pret == -1 and errno == EINTR);

1000

if(pret == -1){

1001

perror_plus("waitpid");

1002

return false;

1003

}

1004

if(WIFEXITED(status)){

1005

if(WEXITSTATUS(status) != 0){

1006

fprintf_plus(stderr, "Error: iprouteadddel exited"

1007

" with status %d\n", WEXITSTATUS(status));

1008

return false;

1009

}

1010

return true;

1011

}

1012

if(WIFSIGNALED(status)){

1013

fprintf_plus(stderr, "Error: iprouteadddel died by"

1014

" signal %d\n", WTERMSIG(status));

1015

return false;

1016

}

1017

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

1018

return false;

1019

}

1020

1021

__attribute__((nonnull, warn_unused_result))

1022

static bool add_local_route(const char *address,

1023

AvahiIfIndex if_index){

1024

if(debug){

1025

fprintf_plus(stderr, "Adding route to %s\n", address);

1026

}

1027

return add_delete_local_route(true, address, if_index);

1028

}

1029

1030

__attribute__((nonnull, warn_unused_result))

1031

static bool delete_local_route(const char *address,

1032

AvahiIfIndex if_index){

1033

if(debug){

1034

fprintf_plus(stderr, "Removing route to %s\n", address);

1035

}

1036

return add_delete_local_route(false, address, if_index);

1037

}

1038

615

1039

/* Called when a Mandos server is found */

616

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

1040

__attribute__((nonnull, warn_unused_result))

1041

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

617

1042

AvahiIfIndex if_index,

618

int af){

1043

int af, mandos_context *mc){

619

1044

int ret, tcp_sd = -1;

620

1045

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1046

struct sockaddr_storage to;

625

1047

char *buffer = NULL;

626

1048

char *decrypted_buffer = NULL;

627

1049

size_t buffer_length = 0;

630

1052

int retval = -1;

631

1053

gnutls_session_t session;

632

1054

int pf; /* Protocol family */

1055

bool route_added = false;

633

1056

634

1057

errno = 0;

635

1058

651

1074

return -1;

652

1075

}

653

1076

654

ret = init_gnutls_session(&session);

1077

/* If the interface is specified and we have a list of interfaces */

1078

if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){

1079

/* Check if the interface is one of the interfaces we are using */

1080

bool match = false;

1081

{

1082

char *interface = NULL;

1083

while((interface = argz_next(mc->interfaces,

1084

mc->interfaces_size,

1085

interface))){

1086

if(if_nametoindex(interface) == (unsigned int)if_index){

1087

match = true;

1088

break;

1089

}

1090

}

1091

}

1092

if(not match){

1093

/* This interface does not match any in the list, so we don't

1094

connect to the server */

1095

if(debug){

1096

char interface[IF_NAMESIZE];

1097

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

1098

perror_plus("if_indextoname");

1099

} else {

1100

fprintf_plus(stderr, "Skipping server on non-used interface"

1101

" \"%s\"\n",

1102

if_indextoname((unsigned int)if_index,

1103

interface));

1104

}

1105

}

1106

return -1;

1107

}

1108

}

1109

1110

ret = init_gnutls_session(&session, mc);

655

1111

if(ret != 0){

656

1112

return -1;

657

1113

}

658

1114

659

1115

if(debug){

660

1116

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

661

PRIu16 "\n", ip, port);

1117

PRIuMAX "\n", ip, (uintmax_t)port);

662

1118

}

663

1119

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1120

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

665

1121

if(tcp_sd < 0){

666

1122

int e = errno;

667

1123

perror_plus("socket");

674

1130

goto mandos_end;

675

1131

}

676

1132

677

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

678

1133

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1134

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1135

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1136

ret = inet_pton(af, ip, &to6->sin6_addr);

681

1137

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

1138

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1139

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1140

ret = inet_pton(af, ip, &to4->sin_addr);

684

1141

}

685

1142

if(ret < 0 ){

686

1143

int e = errno;

695

1152

goto mandos_end;

696

1153

}

697

1154

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

1155

((struct sockaddr_in6 *)&to)->sin6_port = htons(port);

1156

if(IN6_IS_ADDR_LINKLOCAL

1157

(&((struct sockaddr_in6 *)&to)->sin6_addr)){

705

1158

if(if_index == AVAHI_IF_UNSPEC){

706

1159

fprintf_plus(stderr, "An IPv6 link-local address is"

707

1160

" incomplete without a network interface\n");

709

1162

goto mandos_end;

710

1163

}

711

1164

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1165

((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;

713

1166

}

714

1167

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1168

((struct sockaddr_in *)&to)->sin_port = htons(port);

718

1169

}

719

1170

720

1171

if(quit_now){

728

1179

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

729

1180

perror_plus("if_indextoname");

730

1181

} else {

731

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16

732

"\n", ip, interface, port);

1182

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX

1183

"\n", ip, interface, (uintmax_t)port);

733

1184

}

734

1185

} else {

735

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

736

ip, port);

1186

fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",

1187

ip, (uintmax_t)port);

737

1188

}

738

1189

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1190

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

741

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

744

} else {

745

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

746

sizeof(addrstr));

747

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

754

}

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

760

}

761

762

if(af == AF_INET6){

763

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

764

} else {

765

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

766

}

767

if(ret < 0){

768

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

769

int e = errno;

770

perror_plus("connect");

771

errno = e;

772

}

773

goto mandos_end;

774

}

775

776

if(quit_now){

777

errno = EINTR;

778

goto mandos_end;

1191

if(af == AF_INET6){

1192

ret = getnameinfo((struct sockaddr *)&to,

1193

sizeof(struct sockaddr_in6),

1194

addrstr, sizeof(addrstr), NULL, 0,

1195

NI_NUMERICHOST);

1196

} else {

1197

ret = getnameinfo((struct sockaddr *)&to,

1198

sizeof(struct sockaddr_in),

1199

addrstr, sizeof(addrstr), NULL, 0,

1200

NI_NUMERICHOST);

1201

}

1202

if(ret == EAI_SYSTEM){

1203

perror_plus("getnameinfo");

1204

} else if(ret != 0) {

1205

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

1206

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

1207

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

1208

}

1209

}

1210

1211

if(quit_now){

1212

errno = EINTR;

1213

goto mandos_end;

1214

}

1215

1216

while(true){

1217

if(af == AF_INET6){

1218

ret = connect(tcp_sd, (struct sockaddr *)&to,

1219

sizeof(struct sockaddr_in6));

1220

} else {

1221

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

1222

sizeof(struct sockaddr_in));

1223

}

1224

if(ret < 0){

1225

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1226

and if_index != AVAHI_IF_UNSPEC

1227

and connect_to == NULL

1228

and not route_added and

1229

((af == AF_INET6 and not

1230

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1231

&to)->sin6_addr)))

1232

or (af == AF_INET and

1233

/* Not a a IPv4LL address */

1234

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1235

& 0xFFFF0000L) != 0xA9FE0000L))){

1236

/* Work around Avahi bug - Avahi does not announce link-local

1237

addresses if it has a global address, so local hosts with

1238

*only* a link-local address (e.g. Mandos clients) cannot

1239

connect to a Mandos server announced by Avahi on a server

1240

host with a global address. Work around this by retrying

1241

with an explicit route added with the server's address.

1242

1243

Avahi bug reference:

1244

https://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1245

https://bugs.debian.org/587961

1246

*/

1247

if(debug){

1248

fprintf_plus(stderr, "Mandos server unreachable, trying"

1249

" direct route\n");

1250

}

1251

int e = errno;

1252

route_added = add_local_route(ip, if_index);

1253

if(route_added){

1254

continue;

1255

}

1256

errno = e;

1257

}

1258

if(errno != ECONNREFUSED or debug){

1259

int e = errno;

1260

perror_plus("connect");

1261

errno = e;

1262

}

1263

goto mandos_end;

1264

}

1265

1266

if(quit_now){

1267

errno = EINTR;

1268

goto mandos_end;

1269

}

1270

break;

779

1271

}

780

1272

781

1273

const char *out = mandos_protocol_version;

817

1309

goto mandos_end;

818

1310

}

819

1311

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1312

/* This casting via intptr_t is to eliminate warning about casting

1313

an int to a pointer type. This is exactly how the GnuTLS Guile

1314

function "set-session-transport-fd!" does it. */

1315

gnutls_transport_set_ptr(session,

1316

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

1317

823

1318

if(quit_now){

824

1319

errno = EINTR;

929

1424

if(buffer_length > 0){

930

1425

ssize_t decrypted_buffer_size;

931

1426

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1427

&decrypted_buffer, mc);

933

1428

if(decrypted_buffer_size >= 0){

934

1429

1430

clearerr(stdout);

935

1431

written = 0;

936

1432

while(written < (size_t) decrypted_buffer_size){

937

1433

if(quit_now){

953

1449

}

954

1450

written += (size_t)ret;

955

1451

}

1452

ret = fflush(stdout);

1453

if(ret != 0){

1454

int e = errno;

1455

if(debug){

1456

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

1457

strerror(errno));

1458

}

1459

errno = e;

1460

goto mandos_end;

1461

}

956

1462

retval = 0;

957

1463

}

958

1464

}

961

1467

962

1468

mandos_end:

963

1469

{

1470

if(route_added){

1471

if(not delete_local_route(ip, if_index)){

1472

fprintf_plus(stderr, "Failed to delete local route to %s on"

1473

" interface %d", ip, if_index);

1474

}

1475

}

964

1476

int e = errno;

965

1477

free(decrypted_buffer);

966

1478

free(buffer);

967

1479

if(tcp_sd >= 0){

968

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

1480

ret = close(tcp_sd);

969

1481

}

970

1482

if(ret == -1){

971

1483

if(e == 0){

996

1508

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1509

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1510

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1511

void *mc){

1512

if(r == NULL){

1513

return;

1514

}

1001

1515

1002

1516

/* Called whenever a service has been resolved successfully or

1003

1517

timed out */

1004

1518

1005

1519

if(quit_now){

1520

avahi_s_service_resolver_free(r);

1006

1521

return;

1007

1522

}

1008

1523

1012

1527

fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "

1013

1528

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

1014

1529

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1530

avahi_strerror(avahi_server_errno

1531

(((mandos_context*)mc)->server)));

1016

1532

break;

1017

1533

1018

1534

case AVAHI_RESOLVER_FOUND:

1024

1540

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

1025

1541

host_name, ip, (intmax_t)interface, port);

1026

1542

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1543

int ret = start_mandos_communication(ip, (in_port_t)port,

1544

interface,

1545

avahi_proto_to_af(proto),

1546

mc);

1029

1547

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1548

avahi_simple_poll_quit(simple_poll);

1031

1549

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1550

if(not add_server(ip, (in_port_t)port, interface,

1551

avahi_proto_to_af(proto),

1552

&((mandos_context*)mc)->current_server)){

1553

fprintf_plus(stderr, "Failed to add server \"%s\" to server"

1554

" list\n", name);

1555

}

1034

1556

}

1035

1557

}

1036

1558

}

1046

1568

const char *domain,

1047

1569

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1570

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1571

void *mc){

1572

if(b == NULL){

1573

return;

1574

}

1051

1575

1052

1576

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

1053

1577

is removed from the LAN */

1061

1585

case AVAHI_BROWSER_FAILURE:

1062

1586

1063

1587

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1588

avahi_strerror(avahi_server_errno

1589

(((mandos_context*)mc)->server)));

1590

avahi_simple_poll_quit(simple_poll);

1066

1591

return;

1067

1592

1068

1593

case AVAHI_BROWSER_NEW:

1071

1596

the callback function is called the Avahi server will free the

1072

1597

resolver for us. */

1073

1598

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1599

if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,

1600

interface, protocol, name, type,

1601

domain, protocol, 0,

1602

resolve_callback, mc) == NULL)

1077

1603

fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"

1078

1604

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1605

avahi_strerror(avahi_server_errno

1606

(((mandos_context*)mc)->server)));

1080

1607

break;

1081

1608

1082

1609

case AVAHI_BROWSER_REMOVE:

1101

1628

signal_received = sig;

1102

1629

int old_errno = errno;

1103

1630

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1631

if(simple_poll != NULL){

1632

avahi_simple_poll_quit(simple_poll);

1106

1633

}

1107

1634

errno = old_errno;

1108

1635

}

1109

1636

1637

__attribute__((nonnull, warn_unused_result))

1110

1638

bool get_flags(const char *ifname, struct ifreq *ifr){

1111

1639

int ret;

1640

int old_errno;

1112

1641

1113

1642

int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1114

1643

if(s < 0){

1644

old_errno = errno;

1115

1645

perror_plus("socket");

1646

errno = old_errno;

1116

1647

return false;

1117

1648

}

1118

strcpy(ifr->ifr_name, ifname);

1649

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1650

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1119

1651

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1652

if(ret == -1){

1121

1653

if(debug){

1654

old_errno = errno;

1122

1655

perror_plus("ioctl SIOCGIFFLAGS");

1656

errno = old_errno;

1123

1657

}

1124

1658

return false;

1125

1659

}

1126

1660

return true;

1127

1661

}

1128

1662

1663

__attribute__((nonnull, warn_unused_result))

1129

1664

bool good_flags(const char *ifname, const struct ifreq *ifr){

1130

1665

1131

1666

/* Reject the loopback device */

1173

1708

* corresponds to an acceptable network device.

1174

1709

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

1175

1710

*/

1711

__attribute__((nonnull, warn_unused_result))

1176

1712

int good_interface(const struct dirent *if_entry){

1177

1713

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

1178

1714

return 0;

1194

1730

}

1195

1731

1196

1732

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

if(not get_flags(if_entry->d_name, &ifr)){

1208

if(debug){

1209

fprintf_plus(stderr, "Failed to get flags for interface "

1210

"\"%s\"\n", if_entry->d_name);

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

if(not (ifr.ifr_flags & IFF_UP)){

1217

if(debug){

1218

fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

if(not (ifr.ifr_flags & IFF_RUNNING)){

1226

if(debug){

1227

fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

if(not good_flags(if_entry->d_name, &ifr)){

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1733

* This function determines if a network interface is up.

1734

*/

1735

__attribute__((nonnull, warn_unused_result))

1736

bool interface_is_up(const char *interface){

1737

struct ifreq ifr;

1738

if(not get_flags(interface, &ifr)){

1739

if(debug){

1740

fprintf_plus(stderr, "Failed to get flags for interface "

1741

"\"%s\"\n", interface);

1742

}

1743

return false;

1744

}

1745

1746

return (bool)(ifr.ifr_flags & IFF_UP);

1747

}

1748

1749

/*

1750

* This function determines if a network interface is running

1751

*/

1752

__attribute__((nonnull, warn_unused_result))

1753

bool interface_is_running(const char *interface){

1754

struct ifreq ifr;

1755

if(not get_flags(interface, &ifr)){

1756

if(debug){

1757

fprintf_plus(stderr, "Failed to get flags for interface "

1758

"\"%s\"\n", interface);

1759

}

1760

return false;

1761

}

1762

1763

return (bool)(ifr.ifr_flags & IFF_RUNNING);

1764

}

1765

1766

__attribute__((nonnull, pure, warn_unused_result))

1239

1767

int notdotentries(const struct dirent *direntry){

1240

1768

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

1241

1769

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

1248

1776

}

1249

1777

1250

1778

/* Is this directory entry a runnable program? */

1779

__attribute__((nonnull, warn_unused_result))

1251

1780

int runnable_hook(const struct dirent *direntry){

1252

1781

int ret;

1253

1782

size_t sret;

1261

1790

sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

1262

1791

"abcdefghijklmnopqrstuvwxyz"

1263

1792

"0123456789"

1264

"_-");

1793

"_.-");

1265

1794

if((direntry->d_name)[sret] != '\0'){

1266

1795

/* Contains non-allowed characters */

1267

1796

if(debug){

1271

1800

return 0;

1272

1801

}

1273

1802

1274

char *fullname = NULL;

1275

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1803

ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);

1282

1804

if(ret == -1){

1283

1805

if(debug){

1284

1806

perror_plus("Could not stat hook");

1301

1823

}

1302

1824

return 0;

1303

1825

}

1826

if(debug){

1827

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1828

direntry->d_name);

1829

}

1304

1830

return 1;

1305

1831

}

1306

1832

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1833

__attribute__((nonnull, warn_unused_result))

1834

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1835

mandos_context *mc){

1308

1836

int ret;

1309

1837

struct timespec now;

1310

1838

struct timespec waited_time;

1311

1839

intmax_t block_time;

1312

1840

1313

1841

while(true){

1314

if(mc.current_server == NULL){

1315

if (debug){

1842

if(mc->current_server == NULL){

1843

if(debug){

1316

1844

fprintf_plus(stderr, "Wait until first server is found."

1317

1845

" No timeout!\n");

1318

1846

}

1319

1847

ret = avahi_simple_poll_iterate(s, -1);

1320

1848

} else {

1321

if (debug){

1849

if(debug){

1322

1850

fprintf_plus(stderr, "Check current_server if we should run"

1323

1851

" it, or wait\n");

1324

1852

}

1331

1859

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

1332

1860

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

1333

1861

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

1862

- mc->current_server->last_seen.tv_sec);

1335

1863

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

1864

- mc->current_server->last_seen.tv_nsec);

1337

1865

/* total time is 10s/10,000ms.

1338

1866

Converting to s from ms by dividing by 1,000,

1339

1867

and ns to ms by dividing by 1,000,000. */

1341

1869

- ((intmax_t)waited_time.tv_sec * 1000))

1342

1870

- ((intmax_t)waited_time.tv_nsec / 1000000));

1343

1871

1344

if (debug){

1872

if(debug){

1345

1873

fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",

1346

1874

block_time);

1347

1875

}

1348

1876

1349

1877

if(block_time <= 0){

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

1878

ret = start_mandos_communication(mc->current_server->ip,

1879

mc->current_server->port,

1880

mc->current_server->if_index,

1881

mc->current_server->af, mc);

1354

1882

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

1883

avahi_simple_poll_quit(s);

1356

1884

return 0;

1357

1885

}

1358

1886

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

1887

&mc->current_server->last_seen);

1360

1888

if(ret == -1){

1361

1889

perror_plus("clock_gettime");

1362

1890

return -1;

1363

1891

}

1364

mc.current_server = mc.current_server->next;

1892

mc->current_server = mc->current_server->next;

1365

1893

block_time = 0; /* Call avahi to find new Mandos

1366

1894

servers, but don't block */

1367

1895

}

1369

1897

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

1370

1898

}

1371

1899

if(ret != 0){

1372

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

1900

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

1373

1901

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

1374

1902

}

1375

1903

}

1376

1904

}

1377

1905

}

1378

1906

1379

bool run_network_hooks(const char *mode, const char *interface,

1907

__attribute__((nonnull))

1908

void run_network_hooks(const char *mode, const char *interface,

1380

1909

const float delay){

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1385

alphasort);

1910

struct dirent **direntries = NULL;

1911

if(hookdir_fd == -1){

1912

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1913

| O_CLOEXEC);

1914

if(hookdir_fd == -1){

1915

if(errno == ENOENT){

1916

if(debug){

1917

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1918

" found\n", hookdir);

1919

}

1920

} else {

1921

perror_plus("open");

1922

}

1923

return;

1924

}

1925

}

1926

int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));

1927

if(devnull == -1){

1928

perror_plus("open(\"/dev/null\", O_RDONLY)");

1929

return;

1930

}

1931

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1932

runnable_hook, alphasort);

1386

1933

if(numhooks == -1){

1387

1934

perror_plus("scandir");

1388

} else {

1389

int devnull = open("/dev/null", O_RDONLY);

1390

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

1391

direntry = direntries[0];

1392

char *fullname = NULL;

1393

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1394

if(ret < 0){

1935

close(devnull);

1936

return;

1937

}

1938

struct dirent *direntry;

1939

int ret;

1940

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

1941

direntry = direntries[i];

1942

if(debug){

1943

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1944

direntry->d_name);

1945

}

1946

pid_t hook_pid = fork();

1947

if(hook_pid == 0){

1948

/* Child */

1949

/* Raise privileges */

1950

errno = raise_privileges_permanently();

1951

if(errno != 0){

1952

perror_plus("Failed to raise privileges");

1953

_exit(EX_NOPERM);

1954

}

1955

/* Set group */

1956

errno = 0;

1957

ret = setgid(0);

1958

if(ret == -1){

1959

perror_plus("setgid");

1960

_exit(EX_NOPERM);

1961

}

1962

/* Reset supplementary groups */

1963

errno = 0;

1964

ret = setgroups(0, NULL);

1965

if(ret == -1){

1966

perror_plus("setgroups");

1967

_exit(EX_NOPERM);

1968

}

1969

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1970

if(ret == -1){

1971

perror_plus("setenv");

1972

_exit(EX_OSERR);

1973

}

1974

ret = setenv("DEVICE", interface, 1);

1975

if(ret == -1){

1976

perror_plus("setenv");

1977

_exit(EX_OSERR);

1978

}

1979

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1980

if(ret == -1){

1981

perror_plus("setenv");

1982

_exit(EX_OSERR);

1983

}

1984

ret = setenv("MODE", mode, 1);

1985

if(ret == -1){

1986

perror_plus("setenv");

1987

_exit(EX_OSERR);

1988

}

1989

char *delaystring;

1990

ret = asprintf(&delaystring, "%f", (double)delay);

1991

if(ret == -1){

1395

1992

perror_plus("asprintf");

1396

continue;

1993

_exit(EX_OSERR);

1397

1994

}

1398

pid_t hook_pid = fork();

1399

if(hook_pid == 0){

1400

/* Child */

1401

dup2(devnull, STDIN_FILENO);

1402

close(devnull);

1403

dup2(STDERR_FILENO, STDOUT_FILENO);

1404

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1405

if(ret == -1){

1406

perror_plus("setenv");

1407

return false;

1408

}

1409

ret = setenv("DEVICE", interface, 1);

1410

if(ret == -1){

1411

perror_plus("setenv");

1412

return false;

1413

}

1414

ret = setenv("VERBOSE", debug ? "1" : "0", 1);

1415

if(ret == -1){

1416

perror_plus("setenv");

1417

return false;

1418

}

1419

ret = setenv("MODE", mode, 1);

1420

if(ret == -1){

1421

perror_plus("setenv");

1422

return false;

1423

}

1424

char *delaystring;

1425

ret = asprintf(&delaystring, "%f", delay);

1426

if(ret == -1){

1427

perror_plus("asprintf");

1428

return false;

1429

}

1430

ret = setenv("DELAY", delaystring, 1);

1431

if(ret == -1){

1432

free(delaystring);

1433

perror_plus("setenv");

1434

return false;

1435

}

1995

ret = setenv("DELAY", delaystring, 1);

1996

if(ret == -1){

1436

1997

free(delaystring);

1437

ret = execl(fullname, direntry->d_name, mode, NULL);

1438

perror_plus("execl");

1439

} else {

1440

int status;

1441

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1442

perror_plus("waitpid");

1443

free(fullname);

1444

continue;

1445

}

1446

if(WIFEXITED(status)){

1447

if(WEXITSTATUS(status) != 0){

1448

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1449

" with status %d\n", direntry->d_name,

1450

WEXITSTATUS(status));

1451

free(fullname);

1452

continue;

1453

}

1454

} else if(WIFSIGNALED(status)){

1455

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1456

" signal %d\n", direntry->d_name,

1457

WTERMSIG(status));

1458

free(fullname);

1459

continue;

1460

} else {

1461

fprintf_plus(stderr, "Warning: network hook \"%s\""

1462

" crashed\n", direntry->d_name);

1463

free(fullname);

1464

continue;

1465

}

1466

}

1467

free(fullname);

1468

if(quit_now){

1469

break;

1470

}

1471

}

1472

close(devnull);

1473

}

1474

return true;

1998

perror_plus("setenv");

1999

_exit(EX_OSERR);

2000

}

2001

free(delaystring);

2002

if(connect_to != NULL){

2003

ret = setenv("CONNECT", connect_to, 1);

2004

if(ret == -1){

2005

perror_plus("setenv");

2006

_exit(EX_OSERR);

2007

}

2008

}

2009

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

2010

direntry->d_name,

2011

O_RDONLY));

2012

if(hook_fd == -1){

2013

perror_plus("openat");

2014

_exit(EXIT_FAILURE);

2015

}

2016

if(close(hookdir_fd) == -1){

2017

perror_plus("close");

2018

_exit(EXIT_FAILURE);

2019

}

2020

ret = dup2(devnull, STDIN_FILENO);

2021

if(ret == -1){

2022

perror_plus("dup2(devnull, STDIN_FILENO)");

2023

_exit(EX_OSERR);

2024

}

2025

ret = close(devnull);

2026

if(ret == -1){

2027

perror_plus("close");

2028

_exit(EX_OSERR);

2029

}

2030

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2031

if(ret == -1){

2032

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

2033

_exit(EX_OSERR);

2034

}

2035

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

2036

environ) == -1){

2037

perror_plus("fexecve");

2038

_exit(EXIT_FAILURE);

2039

}

2040

} else {

2041

if(hook_pid == -1){

2042

perror_plus("fork");

2043

free(direntry);

2044

continue;

2045

}

2046

int status;

2047

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

2048

perror_plus("waitpid");

2049

free(direntry);

2050

continue;

2051

}

2052

if(WIFEXITED(status)){

2053

if(WEXITSTATUS(status) != 0){

2054

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

2055

" with status %d\n", direntry->d_name,

2056

WEXITSTATUS(status));

2057

free(direntry);

2058

continue;

2059

}

2060

} else if(WIFSIGNALED(status)){

2061

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

2062

" signal %d\n", direntry->d_name,

2063

WTERMSIG(status));

2064

free(direntry);

2065

continue;

2066

} else {

2067

fprintf_plus(stderr, "Warning: network hook \"%s\""

2068

" crashed\n", direntry->d_name);

2069

free(direntry);

2070

continue;

2071

}

2072

}

2073

if(debug){

2074

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

2075

direntry->d_name);

2076

}

2077

free(direntry);

2078

}

2079

free(direntries);

2080

if(close(hookdir_fd) == -1){

2081

perror_plus("close");

2082

} else {

2083

hookdir_fd = -1;

2084

}

2085

close(devnull);

2086

}

2087

2088

__attribute__((nonnull, warn_unused_result))

2089

int bring_up_interface(const char *const interface,

2090

const float delay){

2091

int old_errno = errno;

2092

int ret;

2093

struct ifreq network;

2094

unsigned int if_index = if_nametoindex(interface);

2095

if(if_index == 0){

2096

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

2097

errno = old_errno;

2098

return ENXIO;

2099

}

2100

2101

if(quit_now){

2102

errno = old_errno;

2103

return EINTR;

2104

}

2105

2106

if(not interface_is_up(interface)){

2107

int ret_errno = 0;

2108

int ioctl_errno = 0;

2109

if(not get_flags(interface, &network)){

2110

ret_errno = errno;

2111

fprintf_plus(stderr, "Failed to get flags for interface "

2112

"\"%s\"\n", interface);

2113

errno = old_errno;

2114

return ret_errno;

2115

}

2116

network.ifr_flags |= IFF_UP; /* set flag */

2117

2118

int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

2119

if(sd == -1){

2120

ret_errno = errno;

2121

perror_plus("socket");

2122

errno = old_errno;

2123

return ret_errno;

2124

}

2125

2126

if(quit_now){

2127

ret = close(sd);

2128

if(ret == -1){

2129

perror_plus("close");

2130

}

2131

errno = old_errno;

2132

return EINTR;

2133

}

2134

2135

if(debug){

2136

fprintf_plus(stderr, "Bringing up interface \"%s\"\n",

2137

interface);

2138

}

2139

2140

/* Raise privileges */

2141

ret_errno = raise_privileges();

2142

if(ret_errno != 0){

2143

errno = ret_errno;

2144

perror_plus("Failed to raise privileges");

2145

}

2146

2147

#ifdef __linux__

2148

int ret_linux;

2149

bool restore_loglevel = false;

2150

if(ret_errno == 0){

2151

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2152

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

2153

ret_linux = klogctl(8, NULL, 5);

2154

if(ret_linux == -1){

2155

perror_plus("klogctl");

2156

} else {

2157

restore_loglevel = true;

2158

}

2159

}

2160

#endif /* __linux__ */

2161

int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

2162

ioctl_errno = errno;

2163

#ifdef __linux__

2164

if(restore_loglevel){

2165

ret_linux = klogctl(7, NULL, 0);

2166

if(ret_linux == -1){

2167

perror_plus("klogctl");

2168

}

2169

}

2170

#endif /* __linux__ */

2171

2172

/* If raise_privileges() succeeded above */

2173

if(ret_errno == 0){

2174

/* Lower privileges */

2175

ret_errno = lower_privileges();

2176

if(ret_errno != 0){

2177

errno = ret_errno;

2178

perror_plus("Failed to lower privileges");

2179

}

2180

}

2181

2182

/* Close the socket */

2183

ret = close(sd);

2184

if(ret == -1){

2185

perror_plus("close");

2186

}

2187

2188

if(ret_setflags == -1){

2189

errno = ioctl_errno;

2190

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2191

errno = old_errno;

2192

return ioctl_errno;

2193

}

2194

} else if(debug){

2195

fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",

2196

interface);

2197

}

2198

2199

/* Sleep checking until interface is running.

2200

Check every 0.25s, up to total time of delay */

2201

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

2202

if(interface_is_running(interface)){

2203

break;

2204

}

2205

struct timespec sleeptime = { .tv_nsec = 250000000 };

2206

ret = nanosleep(&sleeptime, NULL);

2207

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

2208

perror_plus("nanosleep");

2209

}

2210

}

2211

2212

errno = old_errno;

2213

return 0;

2214

}

2215

2216

__attribute__((nonnull, warn_unused_result))

2217

int take_down_interface(const char *const interface){

2218

int old_errno = errno;

2219

struct ifreq network;

2220

unsigned int if_index = if_nametoindex(interface);

2221

if(if_index == 0){

2222

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

2223

errno = old_errno;

2224

return ENXIO;

2225

}

2226

if(interface_is_up(interface)){

2227

int ret_errno = 0;

2228

int ioctl_errno = 0;

2229

if(not get_flags(interface, &network) and debug){

2230

ret_errno = errno;

2231

fprintf_plus(stderr, "Failed to get flags for interface "

2232

"\"%s\"\n", interface);

2233

errno = old_errno;

2234

return ret_errno;

2235

}

2236

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

2237

2238

int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

2239

if(sd == -1){

2240

ret_errno = errno;

2241

perror_plus("socket");

2242

errno = old_errno;

2243

return ret_errno;

2244

}

2245

2246

if(debug){

2247

fprintf_plus(stderr, "Taking down interface \"%s\"\n",

2248

interface);

2249

}

2250

2251

/* Raise privileges */

2252

ret_errno = raise_privileges();

2253

if(ret_errno != 0){

2254

errno = ret_errno;

2255

perror_plus("Failed to raise privileges");

2256

}

2257

2258

int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

2259

ioctl_errno = errno;

2260

2261

/* If raise_privileges() succeeded above */

2262

if(ret_errno == 0){

2263

/* Lower privileges */

2264

ret_errno = lower_privileges();

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2267

perror_plus("Failed to lower privileges");

2268

}

2269

}

2270

2271

/* Close the socket */

2272

int ret = close(sd);

2273

if(ret == -1){

2274

perror_plus("close");

2275

}

2276

2277

if(ret_setflags == -1){

2278

errno = ioctl_errno;

2279

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2280

errno = old_errno;

2281

return ioctl_errno;

2282

}

2283

} else if(debug){

2284

fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",

2285

interface);

2286

}

2287

2288

errno = old_errno;

2289

return 0;

1475

2290

}

1476

2291

1477

2292

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

2293

mandos_context mc = { .server = NULL, .dh_bits = 0,

2294

.priority = "SECURE256:!CTYPE-X.509"

2295

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2296

.current_server = NULL, .interfaces = NULL,

2297

.interfaces_size = 0 };

1478

2298

AvahiSServiceBrowser *sb = NULL;

1479

int error;

2299

error_t ret_errno;

1480

2300

int ret;

1481

2301

intmax_t tmpmax;

1482

2302

char *tmp;

1483

2303

int exitcode = EXIT_SUCCESS;

1484

const char *interface = "";

1485

struct ifreq network;

1486

int sd = -1;

1487

bool take_down_interface = false;

1488

uid_t uid;

1489

gid_t gid;

1490

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

1491

bool tempdir_created = false;

2304

char *interfaces_to_take_down = NULL;

2305

size_t interfaces_to_take_down_size = 0;

2306

char run_tempdir[] = "/run/tmp/mandosXXXXXX";

2307

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

2308

char *tempdir = NULL;

1492

2309

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1493

2310

const char *seckey = PATHDIR "/" SECKEY;

1494

2311

const char *pubkey = PATHDIR "/" PUBKEY;

2312

const char *dh_params_file = NULL;

2313

char *interfaces_hooks = NULL;

1495

2314

1496

2315

bool gnutls_initialized = false;

1497

2316

bool gpgme_initialized = false;

1549

2368

.doc = "Bit length of the prime number used in the"

1550

2369

" Diffie-Hellman key exchange",

1551

2370

.group = 2 },

2371

{ .name = "dh-params", .key = 134,

2372

.arg = "FILE",

2373

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2374

" for the Diffie-Hellman key exchange",

2375

.group = 2 },

1552

2376

{ .name = "priority", .key = 130,

1553

2377

.arg = "STRING",

1554

2378

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

1559

2383

.group = 2 },

1560

2384

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

1561

2385

.arg = "SECONDS",

1562

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

2386

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

1563

2387

.group = 2 },

1564

2388

{ .name = "network-hook-dir", .key = 133,

1565

2389

.arg = "DIR",

1588

2412

connect_to = arg;

1589

2413

break;

1590

2414

case 'i': /* --interface */

1591

interface = arg;

2415

ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,

2416

arg, (int)',');

2417

if(ret_errno != 0){

2418

argp_error(state, "%s", strerror(ret_errno));

2419

}

1592

2420

break;

1593

2421

case 's': /* --seckey */

1594

2422

seckey = arg;

1605

2433

}

1606

2434

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

1607

2435

break;

2436

case 134: /* --dh-params */

2437

dh_params_file = arg;

2438

break;

1608

2439

case 130: /* --priority */

1609

2440

mc.priority = arg;

1610

2441

break;

1637

2468

argp_state_help(state, state->out_stream,

1638

2469

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1639

2470

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

1640

fprintf_plus(state->out_stream,

1641

"Mandos plugin mandos-client: ");

1642

2471

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

1643

2472

exit(argp_err_exit_status);

1644

2473

break;

1652

2481

.args_doc = "",

1653

2482

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

1654

2483

" passwords from a Mandos server" };

1655

ret = argp_parse(&argp, argc, argv,

1656

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1657

switch(ret){

2484

ret_errno = argp_parse(&argp, argc, argv,

2485

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2486

switch(ret_errno){

1658

2487

case 0:

1659

2488

break;

1660

2489

case ENOMEM:

1661

2490

default:

1662

errno = ret;

2491

errno = ret_errno;

1663

2492

perror_plus("argp_parse");

1664

2493

exitcode = EX_OSERR;

1665

2494

goto end;

1668

2497

goto end;

1669

2498

}

1670

2499

}

1671

2500

1672

2501

{

1673

2502

/* Work around Debian bug #633582:

1674

<http://bugs.debian.org/633582> */

1675

struct stat st;

1676

1677

/* Re-raise priviliges */

1678

errno = 0;

1679

ret = seteuid(0);

1680

if(ret == -1){

1681

perror_plus("seteuid");

1682

}

1683

1684

if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){

1685

int seckey_fd = open(seckey, O_RDONLY);

1686

if(seckey_fd == -1){

1687

perror_plus("open");

1688

} else {

1689

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

1690

if(ret == -1){

1691

perror_plus("fstat");

1692

} else {

1693

if(S_ISREG(st.st_mode)

1694

and st.st_uid == 0 and st.st_gid == 0){

1695

ret = fchown(seckey_fd, uid, gid);

1696

if(ret == -1){

1697

perror_plus("fchown");

1698

}

1699

}

1700

}

1701

TEMP_FAILURE_RETRY(close(seckey_fd));

1702

}

1703

}

1704

1705

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

1706

int pubkey_fd = open(pubkey, O_RDONLY);

1707

if(pubkey_fd == -1){

1708

perror_plus("open");

1709

} else {

1710

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

1711

if(ret == -1){

1712

perror_plus("fstat");

1713

} else {

1714

if(S_ISREG(st.st_mode)

1715

and st.st_uid == 0 and st.st_gid == 0){

1716

ret = fchown(pubkey_fd, uid, gid);

1717

if(ret == -1){

1718

perror_plus("fchown");

1719

}

1720

}

1721

}

1722

TEMP_FAILURE_RETRY(close(pubkey_fd));

1723

}

1724

}

1725

1726

/* Lower privileges */

1727

errno = 0;

1728

ret = seteuid(uid);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2503

<https://bugs.debian.org/633582> */

2504

2505

/* Re-raise privileges */

2506

ret = raise_privileges();

2507

if(ret != 0){

2508

errno = ret;

2509

perror_plus("Failed to raise privileges");

2510

} else {

2511

struct stat st;

2512

2513

if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){

2514

int seckey_fd = open(seckey, O_RDONLY);

2515

if(seckey_fd == -1){

2516

perror_plus("open");

2517

} else {

2518

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

2519

if(ret == -1){

2520

perror_plus("fstat");

2521

} else {

2522

if(S_ISREG(st.st_mode)

2523

and st.st_uid == 0 and st.st_gid == 0){

2524

ret = fchown(seckey_fd, uid, gid);

2525

if(ret == -1){

2526

perror_plus("fchown");

2527

}

2528

}

2529

}

2530

close(seckey_fd);

2531

}

2532

}

2533

2534

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

2535

int pubkey_fd = open(pubkey, O_RDONLY);

2536

if(pubkey_fd == -1){

2537

perror_plus("open");

2538

} else {

2539

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

2540

if(ret == -1){

2541

perror_plus("fstat");

2542

} else {

2543

if(S_ISREG(st.st_mode)

2544

and st.st_uid == 0 and st.st_gid == 0){

2545

ret = fchown(pubkey_fd, uid, gid);

2546

if(ret == -1){

2547

perror_plus("fchown");

2548

}

2549

}

2550

}

2551

close(pubkey_fd);

2552

}

2553

}

2554

2555

if(dh_params_file != NULL

2556

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2557

int dhparams_fd = open(dh_params_file, O_RDONLY);

2558

if(dhparams_fd == -1){

2559

perror_plus("open");

2560

} else {

2561

ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));

2562

if(ret == -1){

2563

perror_plus("fstat");

2564

} else {

2565

if(S_ISREG(st.st_mode)

2566

and st.st_uid == 0 and st.st_gid == 0){

2567

ret = fchown(dhparams_fd, uid, gid);

2568

if(ret == -1){

2569

perror_plus("fchown");

2570

}

2571

}

2572

}

2573

close(dhparams_fd);

2574

}

2575

}

2576

2577

/* Lower privileges */

2578

ret = lower_privileges();

2579

if(ret != 0){

2580

errno = ret;

2581

perror_plus("Failed to lower privileges");

2582

}

2583

}

2584

}

2585

2586

/* Remove invalid interface names (except "none") */

2587

{

2588

char *interface = NULL;

2589

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2590

interface))){

2591

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

2592

and if_nametoindex(interface) == 0){

2593

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

2594

fprintf_plus(stderr, "Not using nonexisting interface"

2595

" \"%s\"\n", interface);

2596

}

2597

argz_delete(&mc.interfaces, &mc.interfaces_size, interface);

2598

interface = NULL;

2599

}

1731

2600

}

1732

2601

}

1733

2602

1734

2603

/* Run network hooks */

1735

2604

{

1736

/* Re-raise priviliges */

1737

errno = 0;

1738

ret = seteuid(0);

1739

if(ret == -1){

1740

perror_plus("seteuid");

1741

}

1742

if(not run_network_hooks("start", interface, delay)){

1743

goto end;

1744

}

1745

/* Lower privileges */

1746

errno = 0;

1747

ret = seteuid(uid);

1748

if(ret == -1){

1749

perror_plus("seteuid");

1750

}

2605

if(mc.interfaces != NULL){

2606

interfaces_hooks = malloc(mc.interfaces_size);

2607

if(interfaces_hooks == NULL){

2608

perror_plus("malloc");

2609

goto end;

2610

}

2611

memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);

2612

argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');

2613

}

2614

run_network_hooks("start", interfaces_hooks != NULL ?

2615

interfaces_hooks : "", delay);

1751

2616

}

1752

2617

1753

2618

if(not debug){

1754

2619

avahi_set_log_function(empty_log);

1755

2620

}

1756

2621

1757

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

1758

struct dirent **direntries;

1759

/* First look for interfaces that are up */

1760

ret = scandir(sys_class_net, &direntries, up_interface,

1761

alphasort);

1762

if(ret == 0){

1763

/* No up interfaces, look for any good interfaces */

1764

free(direntries);

1765

ret = scandir(sys_class_net, &direntries, good_interface,

1766

alphasort);

1767

}

1768

if(ret >= 1){

1769

/* Pick the first interface returned */

1770

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

1771

if(debug){

1772

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

1773

}

1774

if(interface == NULL){

1775

perror_plus("malloc");

1776

free(direntries);

1777

exitcode = EXIT_FAILURE;

1778

goto end;

1779

}

1780

free(direntries);

1781

} else {

1782

free(direntries);

1783

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

1784

exitcode = EXIT_FAILURE;

1785

goto end;

1786

}

1787

}

1788

1789

2622

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

1790

2623

from the signal handler */

1791

2624

/* Initialize the pseudo-RNG for Avahi */

1792

2625

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

1793

mc.simple_poll = avahi_simple_poll_new();

1794

if(mc.simple_poll == NULL){

2626

simple_poll = avahi_simple_poll_new();

2627

if(simple_poll == NULL){

1795

2628

fprintf_plus(stderr,

1796

2629

"Avahi: Failed to create simple poll object.\n");

1797

2630

exitcode = EX_UNAVAILABLE;

1861

2694

}

1862

2695

}

1863

2696

1864

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

1865

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

1866

if_index = (AvahiIfIndex) if_nametoindex(interface);

1867

if(if_index == 0){

1868

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

1869

exitcode = EX_UNAVAILABLE;

1870

goto end;

1871

}

1872

1873

if(quit_now){

1874

goto end;

1875

}

1876

1877

/* Re-raise priviliges */

1878

errno = 0;

1879

ret = seteuid(0);

1880

if(ret == -1){

1881

perror_plus("seteuid");

1882

}

1883

1884

#ifdef __linux__

1885

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1886

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

1887

ret = klogctl(8, NULL, 5);

1888

bool restore_loglevel = true;

1889

if(ret == -1){

1890

restore_loglevel = false;

1891

perror_plus("klogctl");

1892

}

1893

#endif /* __linux__ */

1894

1895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1896

if(sd < 0){

1897

perror_plus("socket");

1898

exitcode = EX_OSERR;

1899

#ifdef __linux__

1900

if(restore_loglevel){

1901

ret = klogctl(7, NULL, 0);

1902

if(ret == -1){

1903

perror_plus("klogctl");

1904

}

1905

}

1906

#endif /* __linux__ */

1907

/* Lower privileges */

1908

errno = 0;

1909

ret = seteuid(uid);

1910

if(ret == -1){

1911

perror_plus("seteuid");

1912

}

1913

goto end;

1914

}

1915

strcpy(network.ifr_name, interface);

1916

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

1917

if(ret == -1){

1918

perror_plus("ioctl SIOCGIFFLAGS");

1919

#ifdef __linux__

1920

if(restore_loglevel){

1921

ret = klogctl(7, NULL, 0);

1922

if(ret == -1){

1923

perror_plus("klogctl");

1924

}

1925

}

1926

#endif /* __linux__ */

1927

exitcode = EX_OSERR;

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

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

1937

network.ifr_flags |= IFF_UP;

1938

take_down_interface = true;

1939

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

1940

if(ret == -1){

1941

take_down_interface = false;

1942

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1943

exitcode = EX_OSERR;

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

2697

/* If no interfaces were specified, make a list */

2698

if(mc.interfaces == NULL){

2699

struct dirent **direntries = NULL;

2700

/* Look for any good interfaces */

2701

ret = scandir(sys_class_net, &direntries, good_interface,

2702

alphasort);

2703

if(ret >= 1){

2704

/* Add all found interfaces to interfaces list */

2705

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

2706

ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,

2707

direntries[i]->d_name);

2708

if(ret_errno != 0){

2709

errno = ret_errno;

2710

perror_plus("argz_add");

2711

free(direntries[i]);

2712

continue;

2713

}

2714

if(debug){

2715

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2716

direntries[i]->d_name);

2717

}

2718

free(direntries[i]);

2719

}

2720

free(direntries);

2721

} else {

2722

if(ret == 0){

2723

free(direntries);

2724

}

2725

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

2726

exitcode = EXIT_FAILURE;

2727

goto end;

2728

}

2729

}

2730

2731

/* Bring up interfaces which are down, and remove any "none"s */

2732

{

2733

char *interface = NULL;

2734

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2735

interface))){

2736

/* If interface name is "none", stop bringing up interfaces.

2737

Also remove all instances of "none" from the list */

2738

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

2739

argz_delete(&mc.interfaces, &mc.interfaces_size,

2740

interface);

2741

interface = NULL;

2742

while((interface = argz_next(mc.interfaces,

2743

mc.interfaces_size, interface))){

2744

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

2745

argz_delete(&mc.interfaces, &mc.interfaces_size,

2746

interface);

2747

interface = NULL;

1949

2748

}

1950

2749

}

1951

#endif /* __linux__ */

1952

/* Lower privileges */

1953

errno = 0;

1954

ret = seteuid(uid);

1955

if(ret == -1){

1956

perror_plus("seteuid");

1957

}

1958

goto end;

1959

}

1960

}

1961

/* Sleep checking until interface is running.

1962

Check every 0.25s, up to total time of delay */

1963

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

1964

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

1965

if(ret == -1){

1966

perror_plus("ioctl SIOCGIFFLAGS");

1967

} else if(network.ifr_flags & IFF_RUNNING){

1968

2750

break;

1969

2751

}

1970

struct timespec sleeptime = { .tv_nsec = 250000000 };

1971

ret = nanosleep(&sleeptime, NULL);

1972

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

1973

perror_plus("nanosleep");

1974

}

1975

}

1976

if(not take_down_interface){

1977

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

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

}

1983

#ifdef __linux__

1984

if(restore_loglevel){

1985

/* Restores kernel loglevel to default */

1986

ret = klogctl(7, NULL, 0);

1987

if(ret == -1){

1988

perror_plus("klogctl");

1989

}

1990

}

1991

#endif /* __linux__ */

1992

/* Lower privileges */

1993

errno = 0;

1994

/* Lower privileges */

1995

ret = seteuid(uid);

1996

if(ret == -1){

1997

perror_plus("seteuid");

1998

}

2752

bool interface_was_up = interface_is_up(interface);

2753

errno = bring_up_interface(interface, delay);

2754

if(not interface_was_up){

2755

if(errno != 0){

2756

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2757

" %s\n", interface, strerror(errno));

2758

} else {

2759

errno = argz_add(&interfaces_to_take_down,

2760

&interfaces_to_take_down_size,

2761

interface);

2762

if(errno != 0){

2763

perror_plus("argz_add");

2764

}

2765

}

2766

}

2767

}

2768

if(debug and (interfaces_to_take_down == NULL)){

2769

fprintf_plus(stderr, "No interfaces were brought up\n");

2770

}

2771

}

2772

2773

/* If we only got one interface, explicitly use only that one */

2774

if(argz_count(mc.interfaces, mc.interfaces_size) == 1){

2775

if(debug){

2776

fprintf_plus(stderr, "Using only interface \"%s\"\n",

2777

mc.interfaces);

2778

}

2779

if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);

1999

2780

}

2000

2781

2001

2782

if(quit_now){

2002

2783

goto end;

2003

2784

}

2004

2785

2005

ret = init_gnutls_global(pubkey, seckey);

2786

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

2006

2787

if(ret == -1){

2007

2788

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

2008

2789

exitcode = EX_UNAVAILABLE;

2015

2796

goto end;

2016

2797

}

2017

2798

2018

if(mkdtemp(tempdir) == NULL){

2799

/* Try /run/tmp before /tmp */

2800

tempdir = mkdtemp(run_tempdir);

2801

if(tempdir == NULL and errno == ENOENT){

2802

if(debug){

2803

fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",

2804

run_tempdir, old_tempdir);

2805

}

2806

tempdir = mkdtemp(old_tempdir);

2807

}

2808

if(tempdir == NULL){

2019

2809

perror_plus("mkdtemp");

2020

2810

goto end;

2021

2811

}

2022

tempdir_created = true;

2023

2812

2024

2813

if(quit_now){

2025

2814

goto end;

2026

2815

}

2027

2816

2028

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

2817

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

2029

2818

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

2030

2819

exitcode = EX_UNAVAILABLE;

2031

2820

goto end;

2041

2830

/* Connect directly, do not use Zeroconf */

2042

2831

/* (Mainly meant for debugging) */

2043

2832

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

2833

2044

2834

if(address == NULL){

2045

2835

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

2046

2836

exitcode = EX_USAGE;

2051

2841

goto end;

2052

2842

}

2053

2843

2054

uint16_t port;

2844

in_port_t port;

2055

2845

errno = 0;

2056

2846

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

2057

2847

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

2058

or tmpmax != (uint16_t)tmpmax){

2848

or tmpmax != (in_port_t)tmpmax){

2059

2849

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

2060

2850

exitcode = EX_USAGE;

2061

2851

goto end;

2062

2852

}

2063

2853

2064

2854

if(quit_now){

2065

2855

goto end;

2066

2856

}

2067

2857

2068

port = (uint16_t)tmpmax;

2858

port = (in_port_t)tmpmax;

2069

2859

*address = '\0';

2070

2860

/* Colon in address indicates IPv6 */

2071

2861

int af;

2087

2877

}

2088

2878

2089

2879

while(not quit_now){

2090

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

2880

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

2881

&mc);

2091

2882

if(quit_now or ret == 0){

2092

2883

break;

2093

2884

}

2095

2886

fprintf_plus(stderr, "Retrying in %d seconds\n",

2096

2887

(int)retry_interval);

2097

2888

}

2098

sleep((int)retry_interval);

2889

sleep((unsigned int)retry_interval);

2099

2890

}

2100

2891

2101

if (not quit_now){

2892

if(not quit_now){

2102

2893

exitcode = EXIT_SUCCESS;

2103

2894

}

2104

2895

2119

2910

config.publish_domain = 0;

2120

2911

2121

2912

/* Allocate a new server */

2122

mc.server = avahi_server_new(avahi_simple_poll_get

2123

(mc.simple_poll), &config, NULL,

2124

NULL, &error);

2913

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2914

&config, NULL, NULL, &ret);

2125

2915

2126

2916

/* Free the Avahi configuration data */

2127

2917

avahi_server_config_free(&config);

2130

2920

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

2131

2921

if(mc.server == NULL){

2132

2922

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

2133

avahi_strerror(error));

2923

avahi_strerror(ret));

2134

2924

exitcode = EX_UNAVAILABLE;

2135

2925

goto end;

2136

2926

}

2142

2932

/* Create the Avahi service browser */

2143

2933

sb = avahi_s_service_browser_new(mc.server, if_index,

2144

2934

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2145

NULL, 0, browse_callback, NULL);

2935

NULL, 0, browse_callback,

2936

(void *)&mc);

2146

2937

if(sb == NULL){

2147

2938

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

2148

2939

avahi_strerror(avahi_server_errno(mc.server)));

2159

2950

if(debug){

2160

2951

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

2161

2952

}

2162

2163

ret = avahi_loop_with_timeout(mc.simple_poll,

2164

(int)(retry_interval * 1000));

2953

2954

ret = avahi_loop_with_timeout(simple_poll,

2955

(int)(retry_interval * 1000), &mc);

2165

2956

if(debug){

2166

2957

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

2167

2958

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

2170

2961

end:

2171

2962

2172

2963

if(debug){

2173

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

2964

if(signal_received){

2965

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

2966

argv[0], signal_received,

2967

strsignal(signal_received));

2968

} else {

2969

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

2970

}

2174

2971

}

2175

2972

2176

2973

/* Cleanup things */

2974

free(mc.interfaces);

2975

2177

2976

if(sb != NULL)

2178

2977

avahi_s_service_browser_free(sb);

2179

2978

2180

2979

if(mc.server != NULL)

2181

2980

avahi_server_free(mc.server);

2182

2981

2183

if(mc.simple_poll != NULL)

2184

avahi_simple_poll_free(mc.simple_poll);

2982

if(simple_poll != NULL)

2983

avahi_simple_poll_free(simple_poll);

2185

2984

2186

2985

if(gnutls_initialized){

2187

2986

gnutls_certificate_free_credentials(mc.cred);

2188

gnutls_global_deinit();

2189

2987

gnutls_dh_params_deinit(mc.dh_params);

2190

2988

}

2191

2989

2192

2990

if(gpgme_initialized){

2193

2991

gpgme_release(mc.ctx);

2194

2992

}

2195

2993

2196

2994

/* Cleans up the circular linked list of Mandos servers the client

2197

2995

has seen */

2198

2996

if(mc.current_server != NULL){

2199

2997

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

2200

2998

while(mc.current_server != NULL){

2201

2999

server *next = mc.current_server->next;

3000

#ifdef __GNUC__

3001

#pragma GCC diagnostic push

3002

#pragma GCC diagnostic ignored "-Wcast-qual"

3003

#endif

3004

free((char *)(mc.current_server->ip));

3005

#ifdef __GNUC__

3006

#pragma GCC diagnostic pop

3007

#endif

2202

3008

free(mc.current_server);

2203

3009

mc.current_server = next;

2204

3010

}

2205

3011

}

2206

3012

2207

/* Re-raise priviliges */

3013

/* Re-raise privileges */

2208

3014

{

2209

errno = 0;

2210

ret = seteuid(0);

2211

if(ret == -1){

2212

perror_plus("seteuid");

2213

}

2214

/* Run network hooks */

2215

if(not run_network_hooks("stop", interface, delay)){

2216

goto end;

3015

ret = raise_privileges();

3016

if(ret != 0){

3017

errno = ret;

3018

perror_plus("Failed to raise privileges");

3019

} else {

3020

3021

/* Run network hooks */

3022

run_network_hooks("stop", interfaces_hooks != NULL ?

3023

interfaces_hooks : "", delay);

3024

3025

/* Take down the network interfaces which were brought up */

3026

{

3027

char *interface = NULL;

3028

while((interface = argz_next(interfaces_to_take_down,

3029

interfaces_to_take_down_size,

3030

interface))){

3031

ret = take_down_interface(interface);

3032

if(ret != 0){

3033

errno = ret;

3034

perror_plus("Failed to take down interface");

3035

}

3036

}

3037

if(debug and (interfaces_to_take_down == NULL)){

3038

fprintf_plus(stderr, "No interfaces needed to be taken"

3039

" down\n");

3040

}

3041

}

2217

3042

}

2218

3043

2219

/* Take down the network interface */

2220

if(take_down_interface and geteuid() == 0){

2221

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

2222

if(ret == -1){

2223

perror_plus("ioctl SIOCGIFFLAGS");

2224

} else if(network.ifr_flags & IFF_UP){

2225

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

2226

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

2227

if(ret == -1){

2228

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2229

}

2230

}

2231

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

2232

if(ret == -1){

2233

perror_plus("close");

2234

}

3044

ret = lower_privileges_permanently();

3045

if(ret != 0){

3046

errno = ret;

3047

perror_plus("Failed to lower privileges permanently");

2235

3048

}

2236

3049

}

2237

/* Lower privileges permanently */

2238

errno = 0;

2239

ret = setuid(uid);

2240

if(ret == -1){

2241

perror_plus("setuid");

3050

3051

free(interfaces_to_take_down);

3052

free(interfaces_hooks);

3053

3054

void clean_dir_at(int base, const char * const dirname,

3055

uintmax_t level){

3056

struct dirent **direntries = NULL;

3057

int dret;

3058

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3059

O_RDONLY

3060

| O_NOFOLLOW

3061

| O_DIRECTORY

3062

| O_PATH));

3063

if(dir_fd == -1){

3064

perror_plus("open");

3065

return;

3066

}

3067

int numentries = scandirat(dir_fd, ".", &direntries,

3068

notdotentries, alphasort);

3069

if(numentries >= 0){

3070

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

3071

if(debug){

3072

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3073

dirname, direntries[i]->d_name);

3074

}

3075

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3076

if(dret == -1){

3077

if(errno == EISDIR){

3078

dret = unlinkat(dir_fd, direntries[i]->d_name,

3079

AT_REMOVEDIR);

3080

}

3081

if((dret == -1) and (errno == ENOTEMPTY)

3082

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3083

== 0) and (level == 0)){

3084

/* Recurse only in this special case */

3085

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3086

dret = 0;

3087

}

3088

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

3089

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3090

direntries[i]->d_name, strerror(errno));

3091

}

3092

}

3093

free(direntries[i]);

3094

}

3095

3096

/* need to clean even if 0 because man page doesn't specify */

3097

free(direntries);

3098

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3099

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

3100

perror_plus("rmdir");

3101

}

3102

} else {

3103

perror_plus("scandirat");

3104

}

3105

close(dir_fd);

2242

3106

}

2243

3107

2244

3108

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

2245

if(tempdir_created){

2246

struct dirent **direntries = NULL;

2247

struct dirent *direntry = NULL;

2248

int numentries = scandir(tempdir, &direntries, notdotentries,

2249

alphasort);

2250

if (numentries > 0){

2251

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

2252

direntry = direntries[i];

2253

char *fullname = NULL;

2254

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

2255

direntry->d_name);

2256

if(ret < 0){

2257

perror_plus("asprintf");

2258

continue;

2259

}

2260

ret = remove(fullname);

2261

if(ret == -1){

2262

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

2263

strerror(errno));

2264

}

2265

free(fullname);

2266

}

2267

}

2268

2269

/* need to clean even if 0 because man page doesn't specify */

2270

free(direntries);

2271

if (numentries == -1){

2272

perror_plus("scandir");

2273

}

2274

ret = rmdir(tempdir);

2275

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

2276

perror_plus("rmdir");

2277

}

3109

if(tempdir != NULL){

3110

clean_dir_at(-1, tempdir, 0);

2278

3111

}

2279

3112

2280

3113

if(quit_now){