/mandos/release : revision 237.7.478

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

10

*

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* Everything else is

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*

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

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

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

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

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*

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

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13

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*

15

* This file is part of Mandos.

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*

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

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

19

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

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* (at your option) any later version.

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*

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

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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

*

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27

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

26

* along with this program. If not, see

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

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

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29

*

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30

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

30

31

*/

32

33

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

33

34

#ifndef _LARGEFILE_SOURCE

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35

#define _LARGEFILE_SOURCE

35

#endif

36

#endif /* not _LARGEFILE_SOURCE */

36

37

#ifndef _FILE_OFFSET_BITS

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38

#define _FILE_OFFSET_BITS 64

38

#endif

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#endif /* not _FILE_OFFSET_BITS */

39

40

41

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

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42

43

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

43

stdout, ferror(), remove() */

44

stdout, ferror() */

44

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(),

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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,

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EAI_SYSTEM, ENETUNREACH,

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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(), _exit() */

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,

88

95

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

89

96

WEXITSTATUS(), WTERMSIG() */

90

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() */

91

104

92

105

#ifdef __linux__

93

106

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

135

148

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

136

149

char *connect_to = NULL;

137

150

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

138

152

uid_t uid = 65534;

139

153

gid_t gid = 65534;

140

154

141

155

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

142

156

typedef struct server{

143

157

const char *ip;

144

uint16_t port;

158

in_port_t port;

145

159

AvahiIfIndex if_index;

146

160

int af;

147

161

struct timespec last_seen;

151

165

152

166

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

153

167

typedef struct {

154

AvahiSimplePoll *simple_poll;

155

168

AvahiServer *server;

156

169

gnutls_certificate_credentials_t cred;

157

170

unsigned int dh_bits;

159

172

const char *priority;

160

173

gpgme_ctx_t ctx;

161

174

server *current_server;

175

char *interfaces;

176

size_t interfaces_size;

162

177

} mandos_context;

163

178

164

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

165

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

166

.dh_bits = 1024, .priority = "SECURE256"

167

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

168

.current_server = NULL };

179

/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

169

181

170

182

sig_atomic_t quit_now = 0;

171

183

int signal_received = 0;

179

191

perror(print_text);

180

192

}

181

193

182

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

194

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

183

195

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

184

196

va_list ap;

185

197

va_start (ap, format);

186

198

187

199

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

188

200

program_invocation_short_name));

189

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

201

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

190

202

}

191

203

192

204

/*

194

206

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

195

207

* "buffer_length" is how much is already used.

196

208

*/

209

__attribute__((nonnull, warn_unused_result))

197

210

size_t incbuffer(char **buffer, size_t buffer_length,

198

211

size_t buffer_capacity){

199

212

if(buffer_length + BUFFER_SIZE > buffer_capacity){

200

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

201

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;

202

219

return 0;

203

220

}

221

*buffer = new_buf;

204

222

buffer_capacity += BUFFER_SIZE;

205

223

}

206

224

return buffer_capacity;

207

225

}

208

226

209

227

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

210

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

211

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){

212

231

int ret;

213

232

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

214

233

if(new_server == NULL){

221

240

.af = af };

222

241

if(new_server->ip == NULL){

223

242

perror_plus("strdup");

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);

224

258

return false;

225

259

}

226

260

/* Special case of first server */

227

if (mc.current_server == NULL){

261

if(*current_server == NULL){

228

262

new_server->next = new_server;

229

263

new_server->prev = new_server;

230

mc.current_server = new_server;

231

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

264

*current_server = new_server;

232

265

} else {

233

new_server->next = mc.current_server;

234

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;

235

269

new_server->prev->next = new_server;

236

mc.current_server->prev = new_server;

237

}

238

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

239

if(ret == -1){

240

perror_plus("clock_gettime");

241

return false;

270

(*current_server)->prev = new_server;

242

271

}

243

272

return true;

244

273

}

246

275

/*

247

276

* Initialize GPGME.

248

277

*/

249

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

250

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){

251

283

gpgme_error_t rc;

252

284

gpgme_engine_info_t engine_info;

253

285

254

255

286

/*

256

287

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

257

288

*/

258

bool import_key(const char *filename){

289

bool import_key(const char * const filename){

259

290

int ret;

260

291

int fd;

261

292

gpgme_data_t pgp_data;

273

304

return false;

274

305

}

275

306

276

rc = gpgme_op_import(mc.ctx, pgp_data);

307

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

277

308

if(rc != GPG_ERR_NO_ERROR){

278

309

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

279

310

gpgme_strsource(rc), gpgme_strerror(rc));

280

311

return false;

281

312

}

282

313

283

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

314

ret = close(fd);

284

315

if(ret == -1){

285

316

perror_plus("close");

286

317

}

323

354

}

324

355

325

356

/* Create new GPGME "context" */

326

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

357

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

327

358

if(rc != GPG_ERR_NO_ERROR){

328

359

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

329

360

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

342

373

* Decrypt OpenPGP data.

343

374

* Returns -1 on error

344

375

*/

376

__attribute__((nonnull, warn_unused_result))

345

377

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

378

size_t crypto_size,

347

char **plaintext){

379

char **plaintext,

380

mandos_context *mc){

348

381

gpgme_data_t dh_crypto, dh_plain;

349

382

gpgme_error_t rc;

350

383

ssize_t ret;

376

409

377

410

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

378

411

data buffer */

379

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

412

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

380

413

if(rc != GPG_ERR_NO_ERROR){

381

414

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

382

415

gpgme_strsource(rc), gpgme_strerror(rc));

383

416

plaintext_length = -1;

384

417

if(debug){

385

418

gpgme_decrypt_result_t result;

386

result = gpgme_op_decrypt_result(mc.ctx);

419

result = gpgme_op_decrypt_result(mc->ctx);

387

420

if(result == NULL){

388

421

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

389

422

} else {

466

499

return plaintext_length;

467

500

}

468

501

469

static const char * safer_gnutls_strerror(int value){

470

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

471

-Wunreachable-code */

472

if(ret == NULL)

473

ret = "(unknown)";

474

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);

475

513

}

476

514

477

515

/* GnuTLS log function callback */

516

__attribute__((nonnull))

478

517

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

479

518

const char* string){

480

519

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

481

520

}

482

521

522

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

483

523

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename){

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

526

mandos_context *mc){

485

527

int ret;

528

unsigned int uret;

486

529

487

530

if(debug){

488

531

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

489

532

}

490

533

491

ret = gnutls_global_init();

492

if(ret != GNUTLS_E_SUCCESS){

493

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

494

safer_gnutls_strerror(ret));

495

return -1;

496

}

497

498

534

if(debug){

499

535

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

500

536

* - GnuTLS manual

504

540

}

505

541

506

542

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

508

544

if(ret != GNUTLS_E_SUCCESS){

509

545

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

510

546

safer_gnutls_strerror(ret));

511

gnutls_global_deinit();

512

547

return -1;

513

548

}

514

549

520

555

}

521

556

522

557

ret = gnutls_certificate_set_openpgp_key_file

523

(mc.cred, pubkeyfilename, seckeyfilename,

558

(mc->cred, pubkeyfilename, seckeyfilename,

524

559

GNUTLS_OPENPGP_FMT_BASE64);

525

560

if(ret != GNUTLS_E_SUCCESS){

526

561

fprintf_plus(stderr,

532

567

}

533

568

534

569

/* GnuTLS server initialization */

535

ret = gnutls_dh_params_init(&mc.dh_params);

570

ret = gnutls_dh_params_init(&mc->dh_params);

536

571

if(ret != GNUTLS_E_SUCCESS){

537

572

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

573

" initialization: %s\n",

539

574

safer_gnutls_strerror(ret));

540

575

goto globalfail;

541

576

}

542

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

543

if(ret != GNUTLS_E_SUCCESS){

544

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

545

safer_gnutls_strerror(ret));

546

goto globalfail;

547

}

548

549

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);

550

751

551

752

return 0;

552

753

553

754

globalfail:

554

755

555

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

756

gnutls_certificate_free_credentials(mc->cred);

757

gnutls_dh_params_deinit(mc->dh_params);

558

758

return -1;

559

759

}

560

760

561

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){

562

764

int ret;

563

765

/* GnuTLS session creation */

564

766

do {

576

778

{

577

779

const char *err;

578

780

do {

579

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

781

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

580

782

if(quit_now){

581

783

gnutls_deinit(*session);

582

784

return -1;

593

795

594

796

do {

595

797

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

798

mc->cred);

597

799

if(quit_now){

598

800

gnutls_deinit(*session);

599

801

return -1;

609

811

/* ignore client certificate if any. */

610

812

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

813

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

613

614

814

return 0;

615

815

}

616

816

618

818

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

619

819

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

620

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

621

1039

/* Called when a Mandos server is found */

622

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,

623

1042

AvahiIfIndex if_index,

624

int af){

1043

int af, mandos_context *mc){

625

1044

int ret, tcp_sd = -1;

626

1045

ssize_t sret;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

1046

struct sockaddr_storage to;

631

1047

char *buffer = NULL;

632

1048

char *decrypted_buffer = NULL;

633

1049

size_t buffer_length = 0;

636

1052

int retval = -1;

637

1053

gnutls_session_t session;

638

1054

int pf; /* Protocol family */

1055

bool route_added = false;

639

1056

640

1057

errno = 0;

641

1058

657

1074

return -1;

658

1075

}

659

1076

660

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);

661

1111

if(ret != 0){

662

1112

return -1;

663

1113

}

664

1114

665

1115

if(debug){

666

1116

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

667

PRIu16 "\n", ip, port);

1117

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

668

1118

}

669

1119

670

tcp_sd = socket(pf, SOCK_STREAM, 0);

1120

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

671

1121

if(tcp_sd < 0){

672

1122

int e = errno;

673

1123

perror_plus("socket");

680

1130

goto mandos_end;

681

1131

}

682

1132

683

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

684

1133

if(af == AF_INET6){

685

to.in6.sin6_family = (sa_family_t)af;

686

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);

687

1137

} else { /* IPv4 */

688

to.in.sin_family = (sa_family_t)af;

689

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);

690

1141

}

691

1142

if(ret < 0 ){

692

1143

int e = errno;

701

1152

goto mandos_end;

702

1153

}

703

1154

if(af == AF_INET6){

704

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

705

-Wconversion and

706

-Wunreachable-code */

707

708

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

709

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

710

-Wunreachable-code*/

1155

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

1156

if(IN6_IS_ADDR_LINKLOCAL

1157

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

711

1158

if(if_index == AVAHI_IF_UNSPEC){

712

1159

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

713

1160

" incomplete without a network interface\n");

715

1162

goto mandos_end;

716

1163

}

717

1164

/* Set the network interface number as scope */

718

to.in6.sin6_scope_id = (uint32_t)if_index;

1165

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

719

1166

}

720

1167

} else {

721

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

722

-Wconversion and

723

-Wunreachable-code */

1168

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

724

1169

}

725

1170

726

1171

if(quit_now){

734

1179

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

735

1180

perror_plus("if_indextoname");

736

1181

} else {

737

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

738

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

1182

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

1183

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

739

1184

}

740

1185

} else {

741

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

742

ip, port);

1186

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

1187

ip, (uintmax_t)port);

743

1188

}

744

1189

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

745

1190

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

746

const char *pcret;

747

if(af == AF_INET6){

748

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

749

sizeof(addrstr));

750

} else {

751

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

752

sizeof(addrstr));

753

}

754

if(pcret == NULL){

755

perror_plus("inet_ntop");

756

} else {

757

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

758

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

759

}

760

}

761

}

762

763

if(quit_now){

764

errno = EINTR;

765

goto mandos_end;

766

}

767

768

if(af == AF_INET6){

769

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

770

} else {

771

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

772

}

773

if(ret < 0){

774

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

775

int e = errno;

776

perror_plus("connect");

777

errno = e;

778

}

779

goto mandos_end;

780

}

781

782

if(quit_now){

783

errno = EINTR;

784

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;

785

1271

}

786

1272

787

1273

const char *out = mandos_protocol_version;

938

1424

if(buffer_length > 0){

939

1425

ssize_t decrypted_buffer_size;

940

1426

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

941

&decrypted_buffer);

1427

&decrypted_buffer, mc);

942

1428

if(decrypted_buffer_size >= 0){

943

1429

1430

clearerr(stdout);

944

1431

written = 0;

945

1432

while(written < (size_t) decrypted_buffer_size){

946

1433

if(quit_now){

962

1449

}

963

1450

written += (size_t)ret;

964

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

}

965

1462

retval = 0;

966

1463

}

967

1464

}

970

1467

971

1468

mandos_end:

972

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

}

973

1476

int e = errno;

974

1477

free(decrypted_buffer);

975

1478

free(buffer);

976

1479

if(tcp_sd >= 0){

977

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

1480

ret = close(tcp_sd);

978

1481

}

979

1482

if(ret == -1){

980

1483

if(e == 0){

1005

1508

AVAHI_GCC_UNUSED AvahiStringList *txt,

1006

1509

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1007

1510

flags,

1008

AVAHI_GCC_UNUSED void* userdata){

1009

assert(r);

1511

void *mc){

1512

if(r == NULL){

1513

return;

1514

}

1010

1515

1011

1516

/* Called whenever a service has been resolved successfully or

1012

1517

timed out */

1013

1518

1014

1519

if(quit_now){

1520

avahi_s_service_resolver_free(r);

1015

1521

return;

1016

1522

}

1017

1523

1021

1527

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

1022

1528

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

1023

1529

domain,

1024

avahi_strerror(avahi_server_errno(mc.server)));

1530

avahi_strerror(avahi_server_errno

1531

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

1025

1532

break;

1026

1533

1027

1534

case AVAHI_RESOLVER_FOUND:

1033

1540

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

1034

1541

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

1035

1542

}

1036

int ret = start_mandos_communication(ip, port, interface,

1037

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);

1038

1547

if(ret == 0){

1039

avahi_simple_poll_quit(mc.simple_poll);

1548

avahi_simple_poll_quit(simple_poll);

1040

1549

} else {

1041

if(not add_server(ip, port, interface,

1042

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)){

1043

1553

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

1044

1554

" list\n", name);

1045

1555

}

1058

1568

const char *domain,

1059

1569

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1570

flags,

1061

AVAHI_GCC_UNUSED void* userdata){

1062

assert(b);

1571

void *mc){

1572

if(b == NULL){

1573

return;

1574

}

1063

1575

1064

1576

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

1065

1577

is removed from the LAN */

1073

1585

case AVAHI_BROWSER_FAILURE:

1074

1586

1075

1587

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

1076

avahi_strerror(avahi_server_errno(mc.server)));

1077

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);

1078

1591

return;

1079

1592

1080

1593

case AVAHI_BROWSER_NEW:

1083

1596

the callback function is called the Avahi server will free the

1084

1597

resolver for us. */

1085

1598

1086

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

1087

name, type, domain, protocol, 0,

1088

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)

1089

1603

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

1090

1604

" %s\n", name,

1091

avahi_strerror(avahi_server_errno(mc.server)));

1605

avahi_strerror(avahi_server_errno

1606

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

1092

1607

break;

1093

1608

1094

1609

case AVAHI_BROWSER_REMOVE:

1113

1628

signal_received = sig;

1114

1629

int old_errno = errno;

1115

1630

/* set main loop to exit */

1116

if(mc.simple_poll != NULL){

1117

avahi_simple_poll_quit(mc.simple_poll);

1631

if(simple_poll != NULL){

1632

avahi_simple_poll_quit(simple_poll);

1118

1633

}

1119

1634

errno = old_errno;

1120

1635

}

1121

1636

1637

__attribute__((nonnull, warn_unused_result))

1122

1638

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

1123

1639

int ret;

1640

int old_errno;

1124

1641

1125

1642

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

1126

1643

if(s < 0){

1644

old_errno = errno;

1127

1645

perror_plus("socket");

1646

errno = old_errno;

1128

1647

return false;

1129

1648

}

1130

strcpy(ifr->ifr_name, ifname);

1649

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

1650

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

1131

1651

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1132

1652

if(ret == -1){

1133

1653

if(debug){

1654

old_errno = errno;

1134

1655

perror_plus("ioctl SIOCGIFFLAGS");

1656

errno = old_errno;

1135

1657

}

1136

1658

return false;

1137

1659

}

1138

1660

return true;

1139

1661

}

1140

1662

1663

__attribute__((nonnull, warn_unused_result))

1141

1664

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

1142

1665

1143

1666

/* Reject the loopback device */

1185

1708

* corresponds to an acceptable network device.

1186

1709

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

1187

1710

*/

1711

__attribute__((nonnull, warn_unused_result))

1188

1712

int good_interface(const struct dirent *if_entry){

1189

1713

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

1190

1714

return 0;

1206

1730

}

1207

1731

1208

1732

/*

1209

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

1210

* corresponds to an acceptable network device which is up.

1211

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

1212

*/

1213

int up_interface(const struct dirent *if_entry){

1214

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

1215

return 0;

1216

}

1217

1218

struct ifreq ifr;

1219

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

1220

if(debug){

1221

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

1222

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

1223

}

1224

return 0;

1225

}

1226

1227

/* Reject down interfaces */

1228

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

1229

if(debug){

1230

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

1231

if_entry->d_name);

1232

}

1233

return 0;

1234

}

1235

1236

/* Reject non-running interfaces */

1237

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

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

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

1246

return 0;

1247

}

1248

return 1;

1249

}

1250

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))

1251

1767

int notdotentries(const struct dirent *direntry){

1252

1768

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

1253

1769

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

1260

1776

}

1261

1777

1262

1778

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

1779

__attribute__((nonnull, warn_unused_result))

1263

1780

int runnable_hook(const struct dirent *direntry){

1264

1781

int ret;

1265

1782

size_t sret;

1273

1790

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

1274

1791

"abcdefghijklmnopqrstuvwxyz"

1275

1792

"0123456789"

1276

"_-");

1793

"_.-");

1277

1794

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

1278

1795

/* Contains non-allowed characters */

1279

1796

if(debug){

1283

1800

return 0;

1284

1801

}

1285

1802

1286

char *fullname = NULL;

1287

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

1288

if(ret < 0){

1289

perror_plus("asprintf");

1290

return 0;

1291

}

1292

1293

ret = stat(fullname, &st);

1803

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

1294

1804

if(ret == -1){

1295

1805

if(debug){

1296

1806

perror_plus("Could not stat hook");

1320

1830

return 1;

1321

1831

}

1322

1832

1323

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){

1324

1836

int ret;

1325

1837

struct timespec now;

1326

1838

struct timespec waited_time;

1327

1839

intmax_t block_time;

1328

1840

1329

1841

while(true){

1330

if(mc.current_server == NULL){

1331

if (debug){

1842

if(mc->current_server == NULL){

1843

if(debug){

1332

1844

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

1333

1845

" No timeout!\n");

1334

1846

}

1335

1847

ret = avahi_simple_poll_iterate(s, -1);

1336

1848

} else {

1337

if (debug){

1849

if(debug){

1338

1850

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

1339

1851

" it, or wait\n");

1340

1852

}

1347

1859

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

1348

1860

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

1349

1861

waited_time.tv_sec = (now.tv_sec

1350

- mc.current_server->last_seen.tv_sec);

1862

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

1351

1863

waited_time.tv_nsec = (now.tv_nsec

1352

- mc.current_server->last_seen.tv_nsec);

1864

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

1353

1865

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

1354

1866

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

1355

1867

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

1357

1869

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

1358

1870

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

1359

1871

1360

if (debug){

1872

if(debug){

1361

1873

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

1362

1874

block_time);

1363

1875

}

1364

1876

1365

1877

if(block_time <= 0){

1366

ret = start_mandos_communication(mc.current_server->ip,

1367

mc.current_server->port,

1368

mc.current_server->if_index,

1369

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);

1370

1882

if(ret == 0){

1371

avahi_simple_poll_quit(mc.simple_poll);

1883

avahi_simple_poll_quit(s);

1372

1884

return 0;

1373

1885

}

1374

1886

ret = clock_gettime(CLOCK_MONOTONIC,

1375

&mc.current_server->last_seen);

1887

&mc->current_server->last_seen);

1376

1888

if(ret == -1){

1377

1889

perror_plus("clock_gettime");

1378

1890

return -1;

1379

1891

}

1380

mc.current_server = mc.current_server->next;

1892

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

1381

1893

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

1382

1894

servers, but don't block */

1383

1895

}

1385

1897

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

1386

1898

}

1387

1899

if(ret != 0){

1388

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

1900

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

1389

1901

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

1390

1902

}

1391

1903

}

1392

1904

}

1393

1905

}

1394

1906

1395

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

1396

int raise_privileges(void){

1397

int old_errno = errno;

1398

int ret_errno = 0;

1399

errno = 0;

1400

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

1401

perror_plus("seteuid");

1402

}

1403

ret_errno = errno;

1404

errno = old_errno;

1405

return ret_errno;

1406

}

1407

1408

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

1409

int raise_privileges_permanently(void){

1410

int old_errno = errno;

1411

int ret_errno = raise_privileges();

1412

if(ret_errno != 0){

1413

errno = old_errno;

1414

return ret_errno;

1415

}

1416

errno = 0;

1417

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

1418

perror_plus("seteuid");

1419

}

1420

ret_errno = errno;

1421

errno = old_errno;

1422

return ret_errno;

1423

}

1424

1425

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

1426

int lower_privileges(void){

1427

int old_errno = errno;

1428

int ret_errno = 0;

1429

errno = 0;

1430

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

1431

perror_plus("seteuid");

1432

}

1433

ret_errno = errno;

1434

errno = old_errno;

1435

return ret_errno;

1436

}

1437

1438

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

1907

__attribute__((nonnull))

1908

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

1439

1909

const float delay){

1440

struct dirent **direntries;

1441

struct dirent *direntry;

1442

int ret;

1443

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

1444

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

1927

runnable_hook, alphasort);

1445

1928

if(numhooks == -1){

1446

1929

perror_plus("scandir");

1447

} else {

1448

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

1449

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

1450

direntry = direntries[i];

1451

char *fullname = NULL;

1452

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

1453

if(ret < 0){

1930

return;

1931

}

1932

struct dirent *direntry;

1933

int ret;

1934

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

1935

if(devnull == -1){

1936

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

1937

return;

1938

}

1939

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

1940

direntry = direntries[i];

1941

if(debug){

1942

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

1943

direntry->d_name);

1944

}

1945

pid_t hook_pid = fork();

1946

if(hook_pid == 0){

1947

/* Child */

1948

/* Raise privileges */

1949

errno = raise_privileges_permanently();

1950

if(errno != 0){

1951

perror_plus("Failed to raise privileges");

1952

_exit(EX_NOPERM);

1953

}

1954

/* Set group */

1955

errno = 0;

1956

ret = setgid(0);

1957

if(ret == -1){

1958

perror_plus("setgid");

1959

_exit(EX_NOPERM);

1960

}

1961

/* Reset supplementary groups */

1962

errno = 0;

1963

ret = setgroups(0, NULL);

1964

if(ret == -1){

1965

perror_plus("setgroups");

1966

_exit(EX_NOPERM);

1967

}

1968

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

1969

if(ret == -1){

1970

perror_plus("setenv");

1971

_exit(EX_OSERR);

1972

}

1973

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

1974

if(ret == -1){

1975

perror_plus("setenv");

1976

_exit(EX_OSERR);

1977

}

1978

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

1979

if(ret == -1){

1980

perror_plus("setenv");

1981

_exit(EX_OSERR);

1982

}

1983

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

1984

if(ret == -1){

1985

perror_plus("setenv");

1986

_exit(EX_OSERR);

1987

}

1988

char *delaystring;

1989

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

1990

if(ret == -1){

1454

1991

perror_plus("asprintf");

1455

continue;

1456

}

1457

if(debug){

1458

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

1459

direntry->d_name);

1460

}

1461

pid_t hook_pid = fork();

1462

if(hook_pid == 0){

1463

/* Child */

1464

/* Raise privileges */

1465

raise_privileges_permanently();

1466

/* Set group */

1467

errno = 0;

1468

ret = setgid(0);

1469

if(ret == -1){

1470

perror_plus("setgid");

1471

}

1472

/* Reset supplementary groups */

1473

errno = 0;

1474

ret = setgroups(0, NULL);

1475

if(ret == -1){

1476

perror_plus("setgroups");

1477

}

1478

dup2(devnull, STDIN_FILENO);

1479

close(devnull);

1480

dup2(STDERR_FILENO, STDOUT_FILENO);

1481

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

1482

if(ret == -1){

1483

perror_plus("setenv");

1484

_exit(EX_OSERR);

1485

}

1486

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

1487

if(ret == -1){

1488

perror_plus("setenv");

1489

_exit(EX_OSERR);

1490

}

1491

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

1492

if(ret == -1){

1493

perror_plus("setenv");

1494

_exit(EX_OSERR);

1495

}

1496

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

1497

if(ret == -1){

1498

perror_plus("setenv");

1499

_exit(EX_OSERR);

1500

}

1501

char *delaystring;

1502

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

1503

if(ret == -1){

1504

perror_plus("asprintf");

1505

_exit(EX_OSERR);

1506

}

1507

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

1508

if(ret == -1){

1509

free(delaystring);

1510

perror_plus("setenv");

1511

_exit(EX_OSERR);

1512

}

1992

_exit(EX_OSERR);

1993

}

1994

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

1995

if(ret == -1){

1513

1996

free(delaystring);

1514

if(connect_to != NULL){

1515

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

1516

if(ret == -1){

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

}

1521

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1522

perror_plus("execl");

1523

_exit(EXIT_FAILURE);

1524

}

1997

perror_plus("setenv");

1998

_exit(EX_OSERR);

1999

}

2000

free(delaystring);

2001

if(connect_to != NULL){

2002

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

2003

if(ret == -1){

2004

perror_plus("setenv");

2005

_exit(EX_OSERR);

2006

}

2007

}

2008

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

2009

direntry->d_name,

2010

O_RDONLY));

2011

if(hook_fd == -1){

2012

perror_plus("openat");

2013

_exit(EXIT_FAILURE);

2014

}

2015

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

2016

perror_plus("close");

2017

_exit(EXIT_FAILURE);

2018

}

2019

ret = dup2(devnull, STDIN_FILENO);

2020

if(ret == -1){

2021

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

2022

_exit(EX_OSERR);

2023

}

2024

ret = close(devnull);

2025

if(ret == -1){

2026

perror_plus("close");

2027

_exit(EX_OSERR);

2028

}

2029

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2030

if(ret == -1){

2031

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

2032

_exit(EX_OSERR);

2033

}

2034

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

2035

environ) == -1){

2036

perror_plus("fexecve");

2037

_exit(EXIT_FAILURE);

2038

}

2039

} else {

2040

if(hook_pid == -1){

2041

perror_plus("fork");

2042

free(direntry);

2043

continue;

2044

}

2045

int status;

2046

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

2047

perror_plus("waitpid");

2048

free(direntry);

2049

continue;

2050

}

2051

if(WIFEXITED(status)){

2052

if(WEXITSTATUS(status) != 0){

2053

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

2054

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

2055

WEXITSTATUS(status));

2056

free(direntry);

2057

continue;

2058

}

2059

} else if(WIFSIGNALED(status)){

2060

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

2061

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

2062

WTERMSIG(status));

2063

free(direntry);

2064

continue;

1525

2065

} else {

1526

int status;

1527

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

1528

perror_plus("waitpid");

1529

free(fullname);

1530

continue;

1531

}

1532

if(WIFEXITED(status)){

1533

if(WEXITSTATUS(status) != 0){

1534

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

1535

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

1536

WEXITSTATUS(status));

1537

free(fullname);

1538

continue;

1539

}

1540

} else if(WIFSIGNALED(status)){

1541

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

1542

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

1543

WTERMSIG(status));

1544

free(fullname);

1545

continue;

1546

} else {

1547

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

1548

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

1549

free(fullname);

1550

continue;

1551

}

1552

}

1553

free(fullname);

1554

if(debug){

1555

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

1556

direntry->d_name);

1557

}

1558

}

1559

close(devnull);

1560

}

1561

return true;

2066

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

2067

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

2068

free(direntry);

2069

continue;

2070

}

2071

}

2072

if(debug){

2073

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

2074

direntry->d_name);

2075

}

2076

free(direntry);

2077

}

2078

free(direntries);

2079

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

2080

perror_plus("close");

2081

} else {

2082

hookdir_fd = -1;

2083

}

2084

close(devnull);

1562

2085

}

1563

2086

1564

int bring_up_interface(const char * const interface, const float delay){

1565

int sd = -1;

2087

__attribute__((nonnull, warn_unused_result))

2088

int bring_up_interface(const char *const interface,

2089

const float delay){

1566

2090

int old_errno = errno;

1567

int ret_errno = 0;

1568

2091

int ret;

1569

2092

struct ifreq network;

1570

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

2093

unsigned int if_index = if_nametoindex(interface);

1571

2094

if(if_index == 0){

1572

2095

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

1573

2096

errno = old_errno;

1579

2102

return EINTR;

1580

2103

}

1581

2104

1582

/* Re-raise priviliges */

1583

raise_privileges();

1584

1585

#ifdef __linux__

1586

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1587

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

1588

ret = klogctl(8, NULL, 5);

1589

bool restore_loglevel = true;

1590

if(ret == -1){

1591

restore_loglevel = false;

1592

perror_plus("klogctl");

1593

}

1594

#endif /* __linux__ */

1595

1596

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1597

if(sd < 0){

1598

ret_errno = errno;

1599

perror_plus("socket");

1600

#ifdef __linux__

1601

if(restore_loglevel){

1602

ret = klogctl(7, NULL, 0);

1603

if(ret == -1){

1604

perror_plus("klogctl");

1605

}

1606

}

1607

#endif /* __linux__ */

1608

/* Lower privileges */

1609

lower_privileges();

1610

errno = old_errno;

1611

return ret_errno;

1612

}

1613

strcpy(network.ifr_name, interface);

1614

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

1615

if(ret == -1){

1616

ret_errno = errno;

1617

perror_plus("ioctl SIOCGIFFLAGS");

1618

#ifdef __linux__

1619

if(restore_loglevel){

1620

ret = klogctl(7, NULL, 0);

1621

if(ret == -1){

1622

perror_plus("klogctl");

1623

}

1624

}

1625

#endif /* __linux__ */

1626

/* Lower privileges */

1627

lower_privileges();

1628

errno = old_errno;

1629

return ret_errno;

1630

}

1631

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

1632

network.ifr_flags |= IFF_UP;

1633

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

2105

if(not interface_is_up(interface)){

2106

int ret_errno = 0;

2107

int ioctl_errno = 0;

2108

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

2109

ret_errno = errno;

2110

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

2111

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

2112

errno = old_errno;

2113

return ret_errno;

2114

}

2115

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

2116

2117

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

2118

if(sd == -1){

2119

ret_errno = errno;

2120

perror_plus("socket");

2121

errno = old_errno;

2122

return ret_errno;

2123

}

2124

2125

if(quit_now){

2126

ret = close(sd);

2127

if(ret == -1){

2128

perror_plus("close");

2129

}

2130

errno = old_errno;

2131

return EINTR;

2132

}

2133

2134

if(debug){

2135

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

2136

interface);

2137

}

2138

2139

/* Raise privileges */

2140

ret_errno = raise_privileges();

2141

if(ret_errno != 0){

2142

errno = ret_errno;

2143

perror_plus("Failed to raise privileges");

2144

}

2145

2146

#ifdef __linux__

2147

int ret_linux;

2148

bool restore_loglevel = false;

2149

if(ret_errno == 0){

2150

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2151

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

2152

ret_linux = klogctl(8, NULL, 5);

2153

if(ret_linux == -1){

2154

perror_plus("klogctl");

2155

} else {

2156

restore_loglevel = true;

2157

}

2158

}

2159

#endif /* __linux__ */

2160

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

2161

ioctl_errno = errno;

2162

#ifdef __linux__

2163

if(restore_loglevel){

2164

ret_linux = klogctl(7, NULL, 0);

2165

if(ret_linux == -1){

2166

perror_plus("klogctl");

2167

}

2168

}

2169

#endif /* __linux__ */

2170

2171

/* If raise_privileges() succeeded above */

2172

if(ret_errno == 0){

2173

/* Lower privileges */

2174

ret_errno = lower_privileges();

2175

if(ret_errno != 0){

2176

errno = ret_errno;

2177

perror_plus("Failed to lower privileges");

2178

}

2179

}

2180

2181

/* Close the socket */

2182

ret = close(sd);

1634

2183

if(ret == -1){

1635

ret_errno = errno;

2184

perror_plus("close");

2185

}

2186

2187

if(ret_setflags == -1){

2188

errno = ioctl_errno;

1636

2189

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1637

#ifdef __linux__

1638

if(restore_loglevel){

1639

ret = klogctl(7, NULL, 0);

1640

if(ret == -1){

1641

perror_plus("klogctl");

1642

}

1643

}

1644

#endif /* __linux__ */

1645

/* Lower privileges */

1646

lower_privileges();

1647

2190

errno = old_errno;

1648

return ret_errno;

2191

return ioctl_errno;

1649

2192

}

2193

} else if(debug){

2194

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

2195

interface);

1650

2196

}

2197

1651

2198

/* Sleep checking until interface is running.

1652

2199

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

1653

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

1654

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

1655

if(ret == -1){

1656

perror_plus("ioctl SIOCGIFFLAGS");

1657

} else if(network.ifr_flags & IFF_RUNNING){

2200

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

2201

if(interface_is_running(interface)){

1658

2202

break;

1659

2203

}

1660

2204

struct timespec sleeptime = { .tv_nsec = 250000000 };

1663

2207

perror_plus("nanosleep");

1664

2208

}

1665

2209

}

1666

/* Close the socket */

1667

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

1668

if(ret == -1){

1669

perror_plus("close");

2210

2211

errno = old_errno;

2212

return 0;

2213

}

2214

2215

__attribute__((nonnull, warn_unused_result))

2216

int take_down_interface(const char *const interface){

2217

int old_errno = errno;

2218

struct ifreq network;

2219

unsigned int if_index = if_nametoindex(interface);

2220

if(if_index == 0){

2221

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

2222

errno = old_errno;

2223

return ENXIO;

1670

2224

}

1671

#ifdef __linux__

1672

if(restore_loglevel){

1673

/* Restores kernel loglevel to default */

1674

ret = klogctl(7, NULL, 0);

2225

if(interface_is_up(interface)){

2226

int ret_errno = 0;

2227

int ioctl_errno = 0;

2228

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

2229

ret_errno = errno;

2230

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

2231

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

2232

errno = old_errno;

2233

return ret_errno;

2234

}

2235

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

2236

2237

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

2238

if(sd == -1){

2239

ret_errno = errno;

2240

perror_plus("socket");

2241

errno = old_errno;

2242

return ret_errno;

2243

}

2244

2245

if(debug){

2246

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

2247

interface);

2248

}

2249

2250

/* Raise privileges */

2251

ret_errno = raise_privileges();

2252

if(ret_errno != 0){

2253

errno = ret_errno;

2254

perror_plus("Failed to raise privileges");

2255

}

2256

2257

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

2258

ioctl_errno = errno;

2259

2260

/* If raise_privileges() succeeded above */

2261

if(ret_errno == 0){

2262

/* Lower privileges */

2263

ret_errno = lower_privileges();

2264

if(ret_errno != 0){

2265

errno = ret_errno;

2266

perror_plus("Failed to lower privileges");

2267

}

2268

}

2269

2270

/* Close the socket */

2271

int ret = close(sd);

1675

2272

if(ret == -1){

1676

perror_plus("klogctl");

1677

}

2273

perror_plus("close");

2274

}

2275

2276

if(ret_setflags == -1){

2277

errno = ioctl_errno;

2278

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2279

errno = old_errno;

2280

return ioctl_errno;

2281

}

2282

} else if(debug){

2283

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

2284

interface);

1678

2285

}

1679

#endif /* __linux__ */

1680

/* Lower privileges */

1681

lower_privileges();

2286

1682

2287

errno = old_errno;

1683

2288

return 0;

1684

2289

}

1685

2290

1686

2291

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

2292

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

2293

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

2294

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

2295

.current_server = NULL, .interfaces = NULL,

2296

.interfaces_size = 0 };

1687

2297

AvahiSServiceBrowser *sb = NULL;

1688

int error;

2298

error_t ret_errno;

1689

2299

int ret;

1690

2300

intmax_t tmpmax;

1691

2301

char *tmp;

1692

2302

int exitcode = EXIT_SUCCESS;

1693

const char *interface = "";

1694

struct ifreq network;

1695

int sd = -1;

1696

bool take_down_interface = false;

1697

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

1698

bool tempdir_created = false;

2303

char *interfaces_to_take_down = NULL;

2304

size_t interfaces_to_take_down_size = 0;

2305

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

2306

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

2307

char *tempdir = NULL;

1699

2308

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1700

2309

const char *seckey = PATHDIR "/" SECKEY;

1701

2310

const char *pubkey = PATHDIR "/" PUBKEY;

2311

const char *dh_params_file = NULL;

2312

char *interfaces_hooks = NULL;

1702

2313

1703

2314

bool gnutls_initialized = false;

1704

2315

bool gpgme_initialized = false;

1756

2367

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

1757

2368

" Diffie-Hellman key exchange",

1758

2369

.group = 2 },

2370

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

2371

.arg = "FILE",

2372

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

2373

" for the Diffie-Hellman key exchange",

2374

.group = 2 },

1759

2375

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

1760

2376

.arg = "STRING",

1761

2377

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

1795

2411

connect_to = arg;

1796

2412

break;

1797

2413

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

1798

interface = arg;

2414

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

2415

arg, (int)',');

2416

if(ret_errno != 0){

2417

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

2418

}

1799

2419

break;

1800

2420

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

1801

2421

seckey = arg;

1812

2432

}

1813

2433

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

1814

2434

break;

2435

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

2436

dh_params_file = arg;

2437

break;

1815

2438

case 130: /* --priority */

1816

2439

mc.priority = arg;

1817

2440

break;

1857

2480

.args_doc = "",

1858

2481

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

1859

2482

" passwords from a Mandos server" };

1860

ret = argp_parse(&argp, argc, argv,

1861

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1862

switch(ret){

2483

ret_errno = argp_parse(&argp, argc, argv,

2484

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2485

switch(ret_errno){

1863

2486

case 0:

1864

2487

break;

1865

2488

case ENOMEM:

1866

2489

default:

1867

errno = ret;

2490

errno = ret_errno;

1868

2491

perror_plus("argp_parse");

1869

2492

exitcode = EX_OSERR;

1870

2493

goto end;

1873

2496

goto end;

1874

2497

}

1875

2498

}

1876

2499

1877

2500

{

1878

2501

/* Work around Debian bug #633582:

1879

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

2502

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

1880

2503

1881

/* Re-raise priviliges */

1882

if(raise_privileges() == 0){

2504

/* Re-raise privileges */

2505

ret = raise_privileges();

2506

if(ret != 0){

2507

errno = ret;

2508

perror_plus("Failed to raise privileges");

2509

} else {

1883

2510

struct stat st;

1884

2511

1885

2512

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

1899

2526

}

1900

2527

}

1901

2528

}

1902

TEMP_FAILURE_RETRY(close(seckey_fd));

2529

close(seckey_fd);

1903

2530

}

1904

2531

}

1905

2532

1906

2533

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

1907

2534

int pubkey_fd = open(pubkey, O_RDONLY);

1908

2535

if(pubkey_fd == -1){

1920

2547

}

1921

2548

}

1922

2549

}

1923

TEMP_FAILURE_RETRY(close(pubkey_fd));

1924

}

1925

}

1926

2550

close(pubkey_fd);

2551

}

2552

}

2553

2554

if(dh_params_file != NULL

2555

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

2556

int dhparams_fd = open(dh_params_file, O_RDONLY);

2557

if(dhparams_fd == -1){

2558

perror_plus("open");

2559

} else {

2560

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

2561

if(ret == -1){

2562

perror_plus("fstat");

2563

} else {

2564

if(S_ISREG(st.st_mode)

2565

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

2566

ret = fchown(dhparams_fd, uid, gid);

2567

if(ret == -1){

2568

perror_plus("fchown");

2569

}

2570

}

2571

}

2572

close(dhparams_fd);

2573

}

2574

}

2575

1927

2576

/* Lower privileges */

1928

errno = 0;

1929

ret = seteuid(uid);

1930

if(ret == -1){

1931

perror_plus("seteuid");

2577

ret = lower_privileges();

2578

if(ret != 0){

2579

errno = ret;

2580

perror_plus("Failed to lower privileges");

2581

}

2582

}

2583

}

2584

2585

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

2586

{

2587

char *interface = NULL;

2588

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

2589

interface))){

2590

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

2591

and if_nametoindex(interface) == 0){

2592

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

2593

fprintf_plus(stderr, "Not using nonexisting interface"

2594

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

2595

}

2596

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

2597

interface = NULL;

1932

2598

}

1933

2599

}

1934

2600

}

1935

2601

1936

2602

/* Run network hooks */

1937

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

1938

goto end;

2603

{

2604

if(mc.interfaces != NULL){

2605

interfaces_hooks = malloc(mc.interfaces_size);

2606

if(interfaces_hooks == NULL){

2607

perror_plus("malloc");

2608

goto end;

2609

}

2610

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

2611

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

2612

}

2613

run_network_hooks("start", interfaces_hooks != NULL ?

2614

interfaces_hooks : "", delay);

1939

2615

}

1940

2616

1941

2617

if(not debug){

1942

2618

avahi_set_log_function(empty_log);

1943

2619

}

1944

2620

1945

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

1946

struct dirent **direntries;

1947

/* First look for interfaces that are up */

1948

ret = scandir(sys_class_net, &direntries, up_interface,

1949

alphasort);

1950

if(ret == 0){

1951

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

1952

free(direntries);

1953

ret = scandir(sys_class_net, &direntries, good_interface,

1954

alphasort);

1955

}

1956

if(ret >= 1){

1957

/* Pick the first interface returned */

1958

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

1959

if(debug){

1960

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

1961

}

1962

if(interface == NULL){

1963

perror_plus("malloc");

1964

free(direntries);

1965

exitcode = EXIT_FAILURE;

1966

goto end;

1967

}

1968

free(direntries);

1969

} else {

1970

free(direntries);

1971

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

1972

exitcode = EXIT_FAILURE;

1973

goto end;

1974

}

1975

}

1976

1977

2621

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

1978

2622

from the signal handler */

1979

2623

/* Initialize the pseudo-RNG for Avahi */

1980

2624

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

1981

mc.simple_poll = avahi_simple_poll_new();

1982

if(mc.simple_poll == NULL){

2625

simple_poll = avahi_simple_poll_new();

2626

if(simple_poll == NULL){

1983

2627

fprintf_plus(stderr,

1984

2628

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

1985

2629

exitcode = EX_UNAVAILABLE;

2049

2693

}

2050

2694

}

2051

2695

2052

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

2053

if((interface[0] != '\0') and (strcmp(interface, "none") != 0)){

2054

ret = bring_up_interface(interface, delay);

2055

if(ret != 0){

2056

errno = ret;

2057

perror_plus("Failed to bring up interface");

2058

}

2696

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

2697

if(mc.interfaces == NULL){

2698

struct dirent **direntries = NULL;

2699

/* Look for any good interfaces */

2700

ret = scandir(sys_class_net, &direntries, good_interface,

2701

alphasort);

2702

if(ret >= 1){

2703

/* Add all found interfaces to interfaces list */

2704

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

2705

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

2706

direntries[i]->d_name);

2707

if(ret_errno != 0){

2708

errno = ret_errno;

2709

perror_plus("argz_add");

2710

free(direntries[i]);

2711

continue;

2712

}

2713

if(debug){

2714

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

2715

direntries[i]->d_name);

2716

}

2717

free(direntries[i]);

2718

}

2719

free(direntries);

2720

} else {

2721

if(ret == 0){

2722

free(direntries);

2723

}

2724

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

2725

exitcode = EXIT_FAILURE;

2726

goto end;

2727

}

2728

}

2729

2730

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

2731

{

2732

char *interface = NULL;

2733

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

2734

interface))){

2735

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

2736

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

2737

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

2738

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

2739

interface);

2740

interface = NULL;

2741

while((interface = argz_next(mc.interfaces,

2742

mc.interfaces_size, interface))){

2743

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

2744

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

2745

interface);

2746

interface = NULL;

2747

}

2748

}

2749

break;

2750

}

2751

bool interface_was_up = interface_is_up(interface);

2752

errno = bring_up_interface(interface, delay);

2753

if(not interface_was_up){

2754

if(errno != 0){

2755

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

2756

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

2757

} else {

2758

errno = argz_add(&interfaces_to_take_down,

2759

&interfaces_to_take_down_size,

2760

interface);

2761

if(errno != 0){

2762

perror_plus("argz_add");

2763

}

2764

}

2765

}

2766

}

2767

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

2768

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

2769

}

2770

}

2771

2772

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

2773

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

2774

if(debug){

2775

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

2776

mc.interfaces);

2777

}

2778

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

2059

2779

}

2060

2780

2061

2781

if(quit_now){

2062

2782

goto end;

2063

2783

}

2064

2784

2065

ret = init_gnutls_global(pubkey, seckey);

2785

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

2066

2786

if(ret == -1){

2067

2787

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

2068

2788

exitcode = EX_UNAVAILABLE;

2075

2795

goto end;

2076

2796

}

2077

2797

2078

if(mkdtemp(tempdir) == NULL){

2798

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

2799

tempdir = mkdtemp(run_tempdir);

2800

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

2801

if(debug){

2802

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

2803

run_tempdir, old_tempdir);

2804

}

2805

tempdir = mkdtemp(old_tempdir);

2806

}

2807

if(tempdir == NULL){

2079

2808

perror_plus("mkdtemp");

2080

2809

goto end;

2081

2810

}

2082

tempdir_created = true;

2083

2811

2084

2812

if(quit_now){

2085

2813

goto end;

2086

2814

}

2087

2815

2088

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

2816

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

2089

2817

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

2090

2818

exitcode = EX_UNAVAILABLE;

2091

2819

goto end;

2112

2840

goto end;

2113

2841

}

2114

2842

2115

uint16_t port;

2843

in_port_t port;

2116

2844

errno = 0;

2117

2845

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

2118

2846

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

2119

or tmpmax != (uint16_t)tmpmax){

2847

or tmpmax != (in_port_t)tmpmax){

2120

2848

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

2121

2849

exitcode = EX_USAGE;

2122

2850

goto end;

2123

2851

}

2124

2852

2125

2853

if(quit_now){

2126

2854

goto end;

2127

2855

}

2128

2856

2129

port = (uint16_t)tmpmax;

2857

port = (in_port_t)tmpmax;

2130

2858

*address = '\0';

2131

2859

/* Colon in address indicates IPv6 */

2132

2860

int af;

2148

2876

}

2149

2877

2150

2878

while(not quit_now){

2151

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

2879

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

2880

&mc);

2152

2881

if(quit_now or ret == 0){

2153

2882

break;

2154

2883

}

2156

2885

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

2157

2886

(int)retry_interval);

2158

2887

}

2159

sleep((int)retry_interval);

2888

sleep((unsigned int)retry_interval);

2160

2889

}

2161

2890

2162

if (not quit_now){

2891

if(not quit_now){

2163

2892

exitcode = EXIT_SUCCESS;

2164

2893

}

2165

2894

2180

2909

config.publish_domain = 0;

2181

2910

2182

2911

/* Allocate a new server */

2183

mc.server = avahi_server_new(avahi_simple_poll_get

2184

(mc.simple_poll), &config, NULL,

2185

NULL, &error);

2912

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2913

&config, NULL, NULL, &ret);

2186

2914

2187

2915

/* Free the Avahi configuration data */

2188

2916

avahi_server_config_free(&config);

2191

2919

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

2192

2920

if(mc.server == NULL){

2193

2921

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

2194

avahi_strerror(error));

2922

avahi_strerror(ret));

2195

2923

exitcode = EX_UNAVAILABLE;

2196

2924

goto end;

2197

2925

}

2203

2931

/* Create the Avahi service browser */

2204

2932

sb = avahi_s_service_browser_new(mc.server, if_index,

2205

2933

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2206

NULL, 0, browse_callback, NULL);

2934

NULL, 0, browse_callback,

2935

(void *)&mc);

2207

2936

if(sb == NULL){

2208

2937

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

2209

2938

avahi_strerror(avahi_server_errno(mc.server)));

2220

2949

if(debug){

2221

2950

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

2222

2951

}

2223

2224

ret = avahi_loop_with_timeout(mc.simple_poll,

2225

(int)(retry_interval * 1000));

2952

2953

ret = avahi_loop_with_timeout(simple_poll,

2954

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

2226

2955

if(debug){

2227

2956

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

2228

2957

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

2231

2960

end:

2232

2961

2233

2962

if(debug){

2234

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

2963

if(signal_received){

2964

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

2965

argv[0], signal_received,

2966

strsignal(signal_received));

2967

} else {

2968

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

2969

}

2235

2970

}

2236

2971

2237

2972

/* Cleanup things */

2973

free(mc.interfaces);

2974

2238

2975

if(sb != NULL)

2239

2976

avahi_s_service_browser_free(sb);

2240

2977

2241

2978

if(mc.server != NULL)

2242

2979

avahi_server_free(mc.server);

2243

2980

2244

if(mc.simple_poll != NULL)

2245

avahi_simple_poll_free(mc.simple_poll);

2981

if(simple_poll != NULL)

2982

avahi_simple_poll_free(simple_poll);

2246

2983

2247

2984

if(gnutls_initialized){

2248

2985

gnutls_certificate_free_credentials(mc.cred);

2249

gnutls_global_deinit();

2250

2986

gnutls_dh_params_deinit(mc.dh_params);

2251

2987

}

2252

2988

2260

2996

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

2261

2997

while(mc.current_server != NULL){

2262

2998

server *next = mc.current_server->next;

2999

#ifdef __GNUC__

3000

#pragma GCC diagnostic push

3001

#pragma GCC diagnostic ignored "-Wcast-qual"

3002

#endif

3003

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

3004

#ifdef __GNUC__

3005

#pragma GCC diagnostic pop

3006

#endif

2263

3007

free(mc.current_server);

2264

3008

mc.current_server = next;

2265

3009

}

2266

3010

}

2267

3011

2268

/* Run network hooks */

2269

run_network_hooks("stop", interface, delay);

2270

2271

/* Re-raise priviliges */

3012

/* Re-raise privileges */

2272

3013

{

2273

raise_privileges();

3014

ret = raise_privileges();

3015

if(ret != 0){

3016

errno = ret;

3017

perror_plus("Failed to raise privileges");

3018

} else {

3019

3020

/* Run network hooks */

3021

run_network_hooks("stop", interfaces_hooks != NULL ?

3022

interfaces_hooks : "", delay);

3023

3024

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

3025

{

3026

char *interface = NULL;

3027

while((interface = argz_next(interfaces_to_take_down,

3028

interfaces_to_take_down_size,

3029

interface))){

3030

ret = take_down_interface(interface);

3031

if(ret != 0){

3032

errno = ret;

3033

perror_plus("Failed to take down interface");

3034

}

3035

}

3036

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

3037

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

3038

" down\n");

3039

}

3040

}

3041

}

2274

3042

2275

/* Take down the network interface */

2276

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

2277

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

2278

if(ret == -1){

2279

perror_plus("ioctl SIOCGIFFLAGS");

2280

} else if(network.ifr_flags & IFF_UP){

2281

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

2282

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

2283

if(ret == -1){

2284

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2285

}

2286

}

2287

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

2288

if(ret == -1){

2289

perror_plus("close");

2290

}

3043

ret = lower_privileges_permanently();

3044

if(ret != 0){

3045

errno = ret;

3046

perror_plus("Failed to lower privileges permanently");

2291

3047

}

2292

3048

}

2293

/* Lower privileges permanently */

2294

errno = 0;

2295

ret = setuid(uid);

2296

if(ret == -1){

2297

perror_plus("setuid");

3049

3050

free(interfaces_to_take_down);

3051

free(interfaces_hooks);

3052

3053

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

3054

uintmax_t level){

3055

struct dirent **direntries = NULL;

3056

int dret;

3057

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

3058

O_RDONLY

3059

| O_NOFOLLOW

3060

| O_DIRECTORY

3061

| O_PATH));

3062

if(dir_fd == -1){

3063

perror_plus("open");

3064

}

3065

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

3066

notdotentries, alphasort);

3067

if(numentries >= 0){

3068

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

3069

if(debug){

3070

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

3071

dirname, direntries[i]->d_name);

3072

}

3073

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

3074

if(dret == -1){

3075

if(errno == EISDIR){

3076

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

3077

AT_REMOVEDIR);

3078

}

3079

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

3080

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

3081

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

3082

/* Recurse only in this special case */

3083

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

3084

dret = 0;

3085

}

3086

if(dret == -1){

3087

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

3088

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

3089

}

3090

}

3091

free(direntries[i]);

3092

}

3093

3094

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

3095

free(direntries);

3096

if(numentries == -1){

3097

perror_plus("scandirat");

3098

}

3099

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3100

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

3101

perror_plus("rmdir");

3102

}

3103

} else {

3104

perror_plus("scandirat");

3105

}

3106

close(dir_fd);

2298

3107

}

2299

3108

2300

3109

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

2301

if(tempdir_created){

2302

struct dirent **direntries = NULL;

2303

struct dirent *direntry = NULL;

2304

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

2305

alphasort);

2306

if (numentries > 0){

2307

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

2308

direntry = direntries[i];

2309

char *fullname = NULL;

2310

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

2311

direntry->d_name);

2312

if(ret < 0){

2313

perror_plus("asprintf");

2314

continue;

2315

}

2316

ret = remove(fullname);

2317

if(ret == -1){

2318

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

2319

strerror(errno));

2320

}

2321

free(fullname);

2322

}

2323

}

2324

2325

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

2326

free(direntries);

2327

if (numentries == -1){

2328

perror_plus("scandir");

2329

}

2330

ret = rmdir(tempdir);

2331

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

2332

perror_plus("rmdir");

2333

}

3110

if(tempdir != NULL){

3111

clean_dir_at(-1, tempdir, 0);

2334

3112

}

2335

3113

2336

3114

if(quit_now){