/mandos/release : revision 237.7.489

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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

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* 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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* WITHOUT ANY WARRANTY; without even the implied warranty of

22

24

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

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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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*

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

30

31

*/

32

33

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

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34

#ifndef _LARGEFILE_SOURCE

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35

#define _LARGEFILE_SOURCE

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#endif

36

#endif /* not _LARGEFILE_SOURCE */

36

37

#ifndef _FILE_OFFSET_BITS

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38

#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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40

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

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42

43

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

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stdout, ferror(), remove() */

44

stdout, ferror() */

44

45

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

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

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#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() */

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74

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

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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

ret = close(dhpfile);

617

if(ret == -1){

618

perror_plus("close");

619

}

620

if(params.data == NULL){

621

dhparamsfilename = NULL;

622

}

623

if(dhparamsfilename == NULL){

624

break;

625

}

626

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

627

GNUTLS_X509_FMT_PEM);

628

if(ret != GNUTLS_E_SUCCESS){

629

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

630

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

631

safer_gnutls_strerror(ret));

632

dhparamsfilename = NULL;

633

}

634

free(params.data);

635

} while(false);

636

}

637

if(dhparamsfilename == NULL){

638

if(mc->dh_bits == 0){

639

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

640

/* Try to read the private key file */

641

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

642

do {

643

int secfile = open(seckeyfilename, O_RDONLY);

644

if(secfile == -1){

645

perror_plus("open");

646

break;

647

}

648

size_t buffer_capacity = 0;

649

while(true){

650

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

651

(size_t)buffer.size,

652

(size_t)buffer_capacity);

653

if(buffer_capacity == 0){

654

perror_plus("incbuffer");

655

free(buffer.data);

656

buffer.data = NULL;

657

break;

658

}

659

ssize_t bytes_read = read(secfile,

660

buffer.data + buffer.size,

661

BUFFER_SIZE);

662

/* EOF */

663

if(bytes_read == 0){

664

break;

665

}

666

/* check bytes_read for failure */

667

if(bytes_read < 0){

668

perror_plus("read");

669

free(buffer.data);

670

buffer.data = NULL;

671

break;

672

}

673

buffer.size += (unsigned int)bytes_read;

674

}

675

close(secfile);

676

} while(false);

677

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

678

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

679

if(buffer.data != NULL){

680

{

681

gnutls_openpgp_privkey_t privkey = NULL;

682

ret = gnutls_openpgp_privkey_init(&privkey);

683

if(ret != GNUTLS_E_SUCCESS){

684

fprintf_plus(stderr, "Error initializing OpenPGP key"

685

" structure: %s",

686

safer_gnutls_strerror(ret));

687

free(buffer.data);

688

buffer.data = NULL;

689

} else {

690

ret = gnutls_openpgp_privkey_import

691

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

692

if(ret != GNUTLS_E_SUCCESS){

693

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

694

safer_gnutls_strerror(ret));

695

privkey = NULL;

696

}

697

free(buffer.data);

698

buffer.data = NULL;

699

if(privkey != NULL){

700

/* Use private key to suggest an appropriate

701

sec_param */

702

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

703

gnutls_openpgp_privkey_deinit(privkey);

704

if(debug){

705

fprintf_plus(stderr, "This OpenPGP key implies using"

706

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

707

safe_string(gnutls_sec_param_get_name

708

(sec_param)));

709

}

710

}

711

}

712

}

713

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

714

/* Err on the side of caution */

715

sec_param = GNUTLS_SEC_PARAM_ULTRA;

716

if(debug){

717

fprintf_plus(stderr, "Falling back to security parameter"

718

" \"%s\"\n",

719

safe_string(gnutls_sec_param_get_name

720

(sec_param)));

721

}

722

}

723

}

724

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

725

if(uret != 0){

726

mc->dh_bits = uret;

727

if(debug){

728

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

729

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

730

safe_string(gnutls_sec_param_get_name

731

(sec_param)),

732

mc->dh_bits);

733

}

734

} else {

735

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

736

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

737

safe_string(gnutls_sec_param_get_name

738

(sec_param)),

739

safer_gnutls_strerror(ret));

740

goto globalfail;

741

}

742

} else if(debug){

743

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

744

mc->dh_bits);

745

}

746

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

747

if(ret != GNUTLS_E_SUCCESS){

748

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

749

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

750

safer_gnutls_strerror(ret));

751

goto globalfail;

752

}

753

}

754

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

550

755

551

756

return 0;

552

757

553

758

globalfail:

554

759

555

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

760

gnutls_certificate_free_credentials(mc->cred);

761

gnutls_dh_params_deinit(mc->dh_params);

558

762

return -1;

559

763

}

560

764

561

static int init_gnutls_session(gnutls_session_t *session){

765

__attribute__((nonnull, warn_unused_result))

766

static int init_gnutls_session(gnutls_session_t *session,

767

mandos_context *mc){

562

768

int ret;

563

769

/* GnuTLS session creation */

564

770

do {

576

782

{

577

783

const char *err;

578

784

do {

579

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

785

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

580

786

if(quit_now){

581

787

gnutls_deinit(*session);

582

788

return -1;

593

799

594

800

do {

595

801

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

802

mc->cred);

597

803

if(quit_now){

598

804

gnutls_deinit(*session);

599

805

return -1;

609

815

/* ignore client certificate if any. */

610

816

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

817

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

613

614

818

return 0;

615

819

}

616

820

618

822

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

619

823

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

620

824

825

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

826

__attribute__((warn_unused_result))

827

int raise_privileges(void){

828

int old_errno = errno;

829

int ret = 0;

830

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

831

ret = errno;

832

}

833

errno = old_errno;

834

return ret;

835

}

836

837

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

838

__attribute__((warn_unused_result))

839

int raise_privileges_permanently(void){

840

int old_errno = errno;

841

int ret = raise_privileges();

842

if(ret != 0){

843

errno = old_errno;

844

return ret;

845

}

846

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

847

ret = errno;

848

}

849

errno = old_errno;

850

return ret;

851

}

852

853

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

854

__attribute__((warn_unused_result))

855

int lower_privileges(void){

856

int old_errno = errno;

857

int ret = 0;

858

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

859

ret = errno;

860

}

861

errno = old_errno;

862

return ret;

863

}

864

865

/* Lower privileges permanently */

866

__attribute__((warn_unused_result))

867

int lower_privileges_permanently(void){

868

int old_errno = errno;

869

int ret = 0;

870

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

871

ret = errno;

872

}

873

errno = old_errno;

874

return ret;

875

}

876

877

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

878

__attribute__((nonnull, warn_unused_result))

879

static bool add_delete_local_route(const bool add,

880

const char *address,

881

AvahiIfIndex if_index){

882

int ret;

883

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

884

char add_arg[] = "add";

885

char delete_arg[] = "delete";

886

char debug_flag[] = "--debug";

887

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

888

if(pluginhelperdir == NULL){

889

if(debug){

890

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

891

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

892

}

893

return false;

894

}

895

896

char interface[IF_NAMESIZE];

897

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

898

perror_plus("if_indextoname");

899

return false;

900

}

901

902

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

903

if(devnull == -1){

904

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

905

return false;

906

}

907

pid_t pid = fork();

908

if(pid == 0){

909

/* Child */

910

/* Raise privileges */

911

errno = raise_privileges_permanently();

912

if(errno != 0){

913

perror_plus("Failed to raise privileges");

914

/* _exit(EX_NOPERM); */

915

} else {

916

/* Set group */

917

errno = 0;

918

ret = setgid(0);

919

if(ret == -1){

920

perror_plus("setgid");

921

_exit(EX_NOPERM);

922

}

923

/* Reset supplementary groups */

924

errno = 0;

925

ret = setgroups(0, NULL);

926

if(ret == -1){

927

perror_plus("setgroups");

928

_exit(EX_NOPERM);

929

}

930

}

931

ret = dup2(devnull, STDIN_FILENO);

932

if(ret == -1){

933

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

934

_exit(EX_OSERR);

935

}

936

ret = close(devnull);

937

if(ret == -1){

938

perror_plus("close");

939

_exit(EX_OSERR);

940

}

941

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

942

if(ret == -1){

943

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

944

_exit(EX_OSERR);

945

}

946

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

947

O_RDONLY

948

| O_DIRECTORY

949

| O_PATH

950

| O_CLOEXEC));

951

if(helperdir_fd == -1){

952

perror_plus("open");

953

_exit(EX_UNAVAILABLE);

954

}

955

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

956

helper, O_RDONLY));

957

if(helper_fd == -1){

958

perror_plus("openat");

959

close(helperdir_fd);

960

_exit(EX_UNAVAILABLE);

961

}

962

close(helperdir_fd);

963

#ifdef __GNUC__

964

#pragma GCC diagnostic push

965

#pragma GCC diagnostic ignored "-Wcast-qual"

966

#endif

967

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

968

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

969

interface, debug ? debug_flag : NULL, NULL },

970

environ) == -1){

971

#ifdef __GNUC__

972

#pragma GCC diagnostic pop

973

#endif

974

perror_plus("fexecve");

975

_exit(EXIT_FAILURE);

976

}

977

}

978

if(pid == -1){

979

perror_plus("fork");

980

return false;

981

}

982

int status;

983

pid_t pret = -1;

984

errno = 0;

985

do {

986

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

987

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

988

int errno_raising = 0;

989

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

990

errno_raising = errno;

991

perror_plus("Failed to raise privileges in order to"

992

" kill helper program");

993

}

994

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

995

perror_plus("kill");

996

}

997

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

998

perror_plus("Failed to lower privileges after killing"

999

" helper program");

1000

}

1001

return false;

1002

}

1003

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

1004

if(pret == -1){

1005

perror_plus("waitpid");

1006

return false;

1007

}

1008

if(WIFEXITED(status)){

1009

if(WEXITSTATUS(status) != 0){

1010

fprintf_plus(stderr, "Error: iprouteadddel exited"

1011

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

1012

return false;

1013

}

1014

return true;

1015

}

1016

if(WIFSIGNALED(status)){

1017

fprintf_plus(stderr, "Error: iprouteadddel died by"

1018

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

1019

return false;

1020

}

1021

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

1022

return false;

1023

}

1024

1025

__attribute__((nonnull, warn_unused_result))

1026

static bool add_local_route(const char *address,

1027

AvahiIfIndex if_index){

1028

if(debug){

1029

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

1030

}

1031

return add_delete_local_route(true, address, if_index);

1032

}

1033

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool delete_local_route(const char *address,

1036

AvahiIfIndex if_index){

1037

if(debug){

1038

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

1039

}

1040

return add_delete_local_route(false, address, if_index);

1041

}

1042

621

1043

/* Called when a Mandos server is found */

622

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

1044

__attribute__((nonnull, warn_unused_result))

1045

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

623

1046

AvahiIfIndex if_index,

624

int af){

1047

int af, mandos_context *mc){

625

1048

int ret, tcp_sd = -1;

626

1049

ssize_t sret;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

1050

struct sockaddr_storage to;

631

1051

char *buffer = NULL;

632

1052

char *decrypted_buffer = NULL;

633

1053

size_t buffer_length = 0;

636

1056

int retval = -1;

637

1057

gnutls_session_t session;

638

1058

int pf; /* Protocol family */

1059

bool route_added = false;

639

1060

640

1061

errno = 0;

641

1062

657

1078

return -1;

658

1079

}

659

1080

660

ret = init_gnutls_session(&session);

1081

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

1082

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

1083

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

1084

bool match = false;

1085

{

1086

char *interface = NULL;

1087

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

1088

mc->interfaces_size,

1089

interface))){

1090

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

1091

match = true;

1092

break;

1093

}

1094

}

1095

}

1096

if(not match){

1097

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

1098

connect to the server */

1099

if(debug){

1100

char interface[IF_NAMESIZE];

1101

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

1102

perror_plus("if_indextoname");

1103

} else {

1104

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

1105

" \"%s\"\n",

1106

if_indextoname((unsigned int)if_index,

1107

interface));

1108

}

1109

}

1110

return -1;

1111

}

1112

}

1113

1114

ret = init_gnutls_session(&session, mc);

661

1115

if(ret != 0){

662

1116

return -1;

663

1117

}

664

1118

665

1119

if(debug){

666

1120

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

667

PRIu16 "\n", ip, port);

1121

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

668

1122

}

669

1123

670

tcp_sd = socket(pf, SOCK_STREAM, 0);

1124

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

671

1125

if(tcp_sd < 0){

672

1126

int e = errno;

673

1127

perror_plus("socket");

680

1134

goto mandos_end;

681

1135

}

682

1136

683

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

684

1137

if(af == AF_INET6){

685

to.in6.sin6_family = (sa_family_t)af;

686

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

1138

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

1139

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

1140

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

687

1141

} else { /* IPv4 */

688

to.in.sin_family = (sa_family_t)af;

689

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

1142

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

1143

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

1144

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

690

1145

}

691

1146

if(ret < 0 ){

692

1147

int e = errno;

701

1156

goto mandos_end;

702

1157

}

703

1158

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*/

1159

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

1160

if(IN6_IS_ADDR_LINKLOCAL

1161

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

711

1162

if(if_index == AVAHI_IF_UNSPEC){

712

1163

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

713

1164

" incomplete without a network interface\n");

715

1166

goto mandos_end;

716

1167

}

717

1168

/* Set the network interface number as scope */

718

to.in6.sin6_scope_id = (uint32_t)if_index;

1169

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

719

1170

}

720

1171

} else {

721

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

722

-Wconversion and

723

-Wunreachable-code */

1172

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

724

1173

}

725

1174

726

1175

if(quit_now){

734

1183

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

735

1184

perror_plus("if_indextoname");

736

1185

} else {

737

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

738

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

1186

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

1187

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

739

1188

}

740

1189

} else {

741

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

742

ip, port);

1190

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

1191

ip, (uintmax_t)port);

743

1192

}

744

1193

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

745

1194

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;

1195

if(af == AF_INET6){

1196

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

1197

sizeof(struct sockaddr_in6),

1198

addrstr, sizeof(addrstr), NULL, 0,

1199

NI_NUMERICHOST);

1200

} else {

1201

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

1202

sizeof(struct sockaddr_in),

1203

addrstr, sizeof(addrstr), NULL, 0,

1204

NI_NUMERICHOST);

1205

}

1206

if(ret == EAI_SYSTEM){

1207

perror_plus("getnameinfo");

1208

} else if(ret != 0) {

1209

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

1210

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

1211

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

1212

}

1213

}

1214

1215

if(quit_now){

1216

errno = EINTR;

1217

goto mandos_end;

1218

}

1219

1220

while(true){

1221

if(af == AF_INET6){

1222

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

1223

sizeof(struct sockaddr_in6));

1224

} else {

1225

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

1226

sizeof(struct sockaddr_in));

1227

}

1228

if(ret < 0){

1229

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

1230

and if_index != AVAHI_IF_UNSPEC

1231

and connect_to == NULL

1232

and not route_added and

1233

((af == AF_INET6 and not

1234

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1235

&to)->sin6_addr)))

1236

or (af == AF_INET and

1237

/* Not a a IPv4LL address */

1238

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

1239

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

1240

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

1241

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

1242

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

1243

connect to a Mandos server announced by Avahi on a server

1244

host with a global address. Work around this by retrying

1245

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

1246

1247

Avahi bug reference:

1248

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

1249

https://bugs.debian.org/587961

1250

*/

1251

if(debug){

1252

fprintf_plus(stderr, "Mandos server unreachable, trying"

1253

" direct route\n");

1254

}

1255

int e = errno;

1256

route_added = add_local_route(ip, if_index);

1257

if(route_added){

1258

continue;

1259

}

1260

errno = e;

1261

}

1262

if(errno != ECONNREFUSED or debug){

1263

int e = errno;

1264

perror_plus("connect");

1265

errno = e;

1266

}

1267

goto mandos_end;

1268

}

1269

1270

if(quit_now){

1271

errno = EINTR;

1272

goto mandos_end;

1273

}

1274

break;

785

1275

}

786

1276

787

1277

const char *out = mandos_protocol_version;

938

1428

if(buffer_length > 0){

939

1429

ssize_t decrypted_buffer_size;

940

1430

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

941

&decrypted_buffer);

1431

&decrypted_buffer, mc);

942

1432

if(decrypted_buffer_size >= 0){

943

1433

1434

clearerr(stdout);

944

1435

written = 0;

945

1436

while(written < (size_t) decrypted_buffer_size){

946

1437

if(quit_now){

962

1453

}

963

1454

written += (size_t)ret;

964

1455

}

1456

ret = fflush(stdout);

1457

if(ret != 0){

1458

int e = errno;

1459

if(debug){

1460

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

1461

strerror(errno));

1462

}

1463

errno = e;

1464

goto mandos_end;

1465

}

965

1466

retval = 0;

966

1467

}

967

1468

}

970

1471

971

1472

mandos_end:

972

1473

{

1474

if(route_added){

1475

if(not delete_local_route(ip, if_index)){

1476

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

1477

" interface %d", ip, if_index);

1478

}

1479

}

973

1480

int e = errno;

974

1481

free(decrypted_buffer);

975

1482

free(buffer);

976

1483

if(tcp_sd >= 0){

977

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

1484

ret = close(tcp_sd);

978

1485

}

979

1486

if(ret == -1){

980

1487

if(e == 0){

1005

1512

AVAHI_GCC_UNUSED AvahiStringList *txt,

1006

1513

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1007

1514

flags,

1008

AVAHI_GCC_UNUSED void* userdata){

1009

assert(r);

1515

void *mc){

1516

if(r == NULL){

1517

return;

1518

}

1010

1519

1011

1520

/* Called whenever a service has been resolved successfully or

1012

1521

timed out */

1013

1522

1014

1523

if(quit_now){

1524

avahi_s_service_resolver_free(r);

1015

1525

return;

1016

1526

}

1017

1527

1021

1531

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

1022

1532

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

1023

1533

domain,

1024

avahi_strerror(avahi_server_errno(mc.server)));

1534

avahi_strerror(avahi_server_errno

1535

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

1025

1536

break;

1026

1537

1027

1538

case AVAHI_RESOLVER_FOUND:

1033

1544

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

1034

1545

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

1035

1546

}

1036

int ret = start_mandos_communication(ip, port, interface,

1037

avahi_proto_to_af(proto));

1547

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

1548

interface,

1549

avahi_proto_to_af(proto),

1550

mc);

1038

1551

if(ret == 0){

1039

avahi_simple_poll_quit(mc.simple_poll);

1552

avahi_simple_poll_quit(simple_poll);

1040

1553

} else {

1041

if(not add_server(ip, port, interface,

1042

avahi_proto_to_af(proto))){

1554

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

1555

avahi_proto_to_af(proto),

1556

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

1043

1557

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

1044

1558

" list\n", name);

1045

1559

}

1058

1572

const char *domain,

1059

1573

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1574

flags,

1061

AVAHI_GCC_UNUSED void* userdata){

1062

assert(b);

1575

void *mc){

1576

if(b == NULL){

1577

return;

1578

}

1063

1579

1064

1580

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

1065

1581

is removed from the LAN */

1073

1589

case AVAHI_BROWSER_FAILURE:

1074

1590

1075

1591

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

1076

avahi_strerror(avahi_server_errno(mc.server)));

1077

avahi_simple_poll_quit(mc.simple_poll);

1592

avahi_strerror(avahi_server_errno

1593

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

1594

avahi_simple_poll_quit(simple_poll);

1078

1595

return;

1079

1596

1080

1597

case AVAHI_BROWSER_NEW:

1083

1600

the callback function is called the Avahi server will free the

1084

1601

resolver for us. */

1085

1602

1086

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

1087

name, type, domain, protocol, 0,

1088

resolve_callback, NULL) == NULL)

1603

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

1604

interface, protocol, name, type,

1605

domain, protocol, 0,

1606

resolve_callback, mc) == NULL)

1089

1607

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

1090

1608

" %s\n", name,

1091

avahi_strerror(avahi_server_errno(mc.server)));

1609

avahi_strerror(avahi_server_errno

1610

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

1092

1611

break;

1093

1612

1094

1613

case AVAHI_BROWSER_REMOVE:

1113

1632

signal_received = sig;

1114

1633

int old_errno = errno;

1115

1634

/* set main loop to exit */

1116

if(mc.simple_poll != NULL){

1117

avahi_simple_poll_quit(mc.simple_poll);

1635

if(simple_poll != NULL){

1636

avahi_simple_poll_quit(simple_poll);

1118

1637

}

1119

1638

errno = old_errno;

1120

1639

}

1121

1640

1641

__attribute__((nonnull, warn_unused_result))

1122

1642

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

1123

1643

int ret;

1644

int old_errno;

1124

1645

1125

1646

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

1126

1647

if(s < 0){

1648

old_errno = errno;

1127

1649

perror_plus("socket");

1650

errno = old_errno;

1128

1651

return false;

1129

1652

}

1130

strcpy(ifr->ifr_name, ifname);

1653

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

1654

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

1131

1655

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1132

1656

if(ret == -1){

1133

1657

if(debug){

1658

old_errno = errno;

1134

1659

perror_plus("ioctl SIOCGIFFLAGS");

1660

errno = old_errno;

1661

}

1662

if((close(s) == -1) and debug){

1663

old_errno = errno;

1664

perror_plus("close");

1665

errno = old_errno;

1135

1666

}

1136

1667

return false;

1137

1668

}

1669

if((close(s) == -1) and debug){

1670

old_errno = errno;

1671

perror_plus("close");

1672

errno = old_errno;

1673

}

1138

1674

return true;

1139

1675

}

1140

1676

1677

__attribute__((nonnull, warn_unused_result))

1141

1678

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

1142

1679

1143

1680

/* Reject the loopback device */

1185

1722

* corresponds to an acceptable network device.

1186

1723

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

1187

1724

*/

1725

__attribute__((nonnull, warn_unused_result))

1188

1726

int good_interface(const struct dirent *if_entry){

1189

1727

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

1190

1728

return 0;

1206

1744

}

1207

1745

1208

1746

/*

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

1747

* This function determines if a network interface is up.

1748

*/

1749

__attribute__((nonnull, warn_unused_result))

1750

bool interface_is_up(const char *interface){

1751

struct ifreq ifr;

1752

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

1753

if(debug){

1754

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

1755

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

1756

}

1757

return false;

1758

}

1759

1760

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

1761

}

1762

1763

/*

1764

* This function determines if a network interface is running

1765

*/

1766

__attribute__((nonnull, warn_unused_result))

1767

bool interface_is_running(const char *interface){

1768

struct ifreq ifr;

1769

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

1770

if(debug){

1771

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

1772

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

1773

}

1774

return false;

1775

}

1776

1777

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

1778

}

1779

1780

__attribute__((nonnull, pure, warn_unused_result))

1251

1781

int notdotentries(const struct dirent *direntry){

1252

1782

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

1253

1783

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

1260

1790

}

1261

1791

1262

1792

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

1793

__attribute__((nonnull, warn_unused_result))

1263

1794

int runnable_hook(const struct dirent *direntry){

1264

1795

int ret;

1265

1796

size_t sret;

1273

1804

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

1274

1805

"abcdefghijklmnopqrstuvwxyz"

1275

1806

"0123456789"

1276

"_-");

1807

"_.-");

1277

1808

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

1278

1809

/* Contains non-allowed characters */

1279

1810

if(debug){

1283

1814

return 0;

1284

1815

}

1285

1816

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);

1817

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

1294

1818

if(ret == -1){

1295

1819

if(debug){

1296

1820

perror_plus("Could not stat hook");

1320

1844

return 1;

1321

1845

}

1322

1846

1323

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1847

__attribute__((nonnull, warn_unused_result))

1848

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1849

mandos_context *mc){

1324

1850

int ret;

1325

1851

struct timespec now;

1326

1852

struct timespec waited_time;

1327

1853

intmax_t block_time;

1328

1854

1329

1855

while(true){

1330

if(mc.current_server == NULL){

1331

if (debug){

1856

if(mc->current_server == NULL){

1857

if(debug){

1332

1858

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

1333

1859

" No timeout!\n");

1334

1860

}

1335

1861

ret = avahi_simple_poll_iterate(s, -1);

1336

1862

} else {

1337

if (debug){

1863

if(debug){

1338

1864

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

1339

1865

" it, or wait\n");

1340

1866

}

1347

1873

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

1348

1874

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

1349

1875

waited_time.tv_sec = (now.tv_sec

1350

- mc.current_server->last_seen.tv_sec);

1876

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

1351

1877

waited_time.tv_nsec = (now.tv_nsec

1352

- mc.current_server->last_seen.tv_nsec);

1878

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

1353

1879

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

1354

1880

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

1355

1881

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

1357

1883

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

1358

1884

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

1359

1885

1360

if (debug){

1886

if(debug){

1361

1887

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

1362

1888

block_time);

1363

1889

}

1364

1890

1365

1891

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);

1892

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

1893

mc->current_server->port,

1894

mc->current_server->if_index,

1895

mc->current_server->af, mc);

1370

1896

if(ret == 0){

1371

avahi_simple_poll_quit(mc.simple_poll);

1897

avahi_simple_poll_quit(s);

1372

1898

return 0;

1373

1899

}

1374

1900

ret = clock_gettime(CLOCK_MONOTONIC,

1375

&mc.current_server->last_seen);

1901

&mc->current_server->last_seen);

1376

1902

if(ret == -1){

1377

1903

perror_plus("clock_gettime");

1378

1904

return -1;

1379

1905

}

1380

mc.current_server = mc.current_server->next;

1906

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

1381

1907

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

1382

1908

servers, but don't block */

1383

1909

}

1385

1911

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

1386

1912

}

1387

1913

if(ret != 0){

1388

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

1914

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

1389

1915

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

1390

1916

}

1391

1917

}

1392

1918

}

1393

1919

}

1394

1920

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,

1921

__attribute__((nonnull))

1922

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

1439

1923

const float delay){

1440

struct dirent **direntries;

1441

struct dirent *direntry;

1442

int ret;

1443

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

1444

alphasort);

1924

struct dirent **direntries = NULL;

1925

if(hookdir_fd == -1){

1926

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1927

| O_CLOEXEC);

1928

if(hookdir_fd == -1){

1929

if(errno == ENOENT){

1930

if(debug){

1931

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

1932

" found\n", hookdir);

1933

}

1934

} else {

1935

perror_plus("open");

1936

}

1937

return;

1938

}

1939

}

1940

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

1941

if(devnull == -1){

1942

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

1943

return;

1944

}

1945

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

1946

runnable_hook, alphasort);

1445

1947

if(numhooks == -1){

1446

1948

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){

1949

close(devnull);

1950

return;

1951

}

1952

struct dirent *direntry;

1953

int ret;

1954

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

1955

direntry = direntries[i];

1956

if(debug){

1957

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

1958

direntry->d_name);

1959

}

1960

pid_t hook_pid = fork();

1961

if(hook_pid == 0){

1962

/* Child */

1963

/* Raise privileges */

1964

errno = raise_privileges_permanently();

1965

if(errno != 0){

1966

perror_plus("Failed to raise privileges");

1967

_exit(EX_NOPERM);

1968

}

1969

/* Set group */

1970

errno = 0;

1971

ret = setgid(0);

1972

if(ret == -1){

1973

perror_plus("setgid");

1974

_exit(EX_NOPERM);

1975

}

1976

/* Reset supplementary groups */

1977

errno = 0;

1978

ret = setgroups(0, NULL);

1979

if(ret == -1){

1980

perror_plus("setgroups");

1981

_exit(EX_NOPERM);

1982

}

1983

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

1984

if(ret == -1){

1985

perror_plus("setenv");

1986

_exit(EX_OSERR);

1987

}

1988

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

1989

if(ret == -1){

1990

perror_plus("setenv");

1991

_exit(EX_OSERR);

1992

}

1993

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

1994

if(ret == -1){

1995

perror_plus("setenv");

1996

_exit(EX_OSERR);

1997

}

1998

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

1999

if(ret == -1){

2000

perror_plus("setenv");

2001

_exit(EX_OSERR);

2002

}

2003

char *delaystring;

2004

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

2005

if(ret == -1){

1454

2006

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

}

2007

_exit(EX_OSERR);

2008

}

2009

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

2010

if(ret == -1){

1513

2011

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

}

2012

perror_plus("setenv");

2013

_exit(EX_OSERR);

2014

}

2015

free(delaystring);

2016

if(connect_to != NULL){

2017

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

2018

if(ret == -1){

2019

perror_plus("setenv");

2020

_exit(EX_OSERR);

2021

}

2022

}

2023

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

2024

direntry->d_name,

2025

O_RDONLY));

2026

if(hook_fd == -1){

2027

perror_plus("openat");

2028

_exit(EXIT_FAILURE);

2029

}

2030

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

2031

perror_plus("close");

2032

_exit(EXIT_FAILURE);

2033

}

2034

ret = dup2(devnull, STDIN_FILENO);

2035

if(ret == -1){

2036

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

2037

_exit(EX_OSERR);

2038

}

2039

ret = close(devnull);

2040

if(ret == -1){

2041

perror_plus("close");

2042

_exit(EX_OSERR);

2043

}

2044

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2045

if(ret == -1){

2046

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

2047

_exit(EX_OSERR);

2048

}

2049

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

2050

environ) == -1){

2051

perror_plus("fexecve");

2052

_exit(EXIT_FAILURE);

2053

}

2054

} else {

2055

if(hook_pid == -1){

2056

perror_plus("fork");

2057

free(direntry);

2058

continue;

2059

}

2060

int status;

2061

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

2062

perror_plus("waitpid");

2063

free(direntry);

2064

continue;

2065

}

2066

if(WIFEXITED(status)){

2067

if(WEXITSTATUS(status) != 0){

2068

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

2069

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

2070

WEXITSTATUS(status));

2071

free(direntry);

2072

continue;

2073

}

2074

} else if(WIFSIGNALED(status)){

2075

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

2076

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

2077

WTERMSIG(status));

2078

free(direntry);

2079

continue;

1525

2080

} 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;

2081

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

2082

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

2083

free(direntry);

2084

continue;

2085

}

2086

}

2087

if(debug){

2088

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

2089

direntry->d_name);

2090

}

2091

free(direntry);

2092

}

2093

free(direntries);

2094

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

2095

perror_plus("close");

2096

} else {

2097

hookdir_fd = -1;

2098

}

2099

close(devnull);

1562

2100

}

1563

2101

1564

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

1565

int sd = -1;

2102

__attribute__((nonnull, warn_unused_result))

2103

int bring_up_interface(const char *const interface,

2104

const float delay){

1566

2105

int old_errno = errno;

1567

int ret_errno = 0;

1568

2106

int ret;

1569

2107

struct ifreq network;

1570

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

2108

unsigned int if_index = if_nametoindex(interface);

1571

2109

if(if_index == 0){

1572

2110

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

1573

2111

errno = old_errno;

1579

2117

return EINTR;

1580

2118

}

1581

2119

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);

2120

if(not interface_is_up(interface)){

2121

int ret_errno = 0;

2122

int ioctl_errno = 0;

2123

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

2124

ret_errno = errno;

2125

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

2126

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

2127

errno = old_errno;

2128

return ret_errno;

2129

}

2130

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

2131

2132

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

2133

if(sd == -1){

2134

ret_errno = errno;

2135

perror_plus("socket");

2136

errno = old_errno;

2137

return ret_errno;

2138

}

2139

2140

if(quit_now){

2141

ret = close(sd);

2142

if(ret == -1){

2143

perror_plus("close");

2144

}

2145

errno = old_errno;

2146

return EINTR;

2147

}

2148

2149

if(debug){

2150

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

2151

interface);

2152

}

2153

2154

/* Raise privileges */

2155

ret_errno = raise_privileges();

2156

if(ret_errno != 0){

2157

errno = ret_errno;

2158

perror_plus("Failed to raise privileges");

2159

}

2160

2161

#ifdef __linux__

2162

int ret_linux;

2163

bool restore_loglevel = false;

2164

if(ret_errno == 0){

2165

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2166

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

2167

ret_linux = klogctl(8, NULL, 5);

2168

if(ret_linux == -1){

2169

perror_plus("klogctl");

2170

} else {

2171

restore_loglevel = true;

2172

}

2173

}

2174

#endif /* __linux__ */

2175

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

2176

ioctl_errno = errno;

2177

#ifdef __linux__

2178

if(restore_loglevel){

2179

ret_linux = klogctl(7, NULL, 0);

2180

if(ret_linux == -1){

2181

perror_plus("klogctl");

2182

}

2183

}

2184

#endif /* __linux__ */

2185

2186

/* If raise_privileges() succeeded above */

2187

if(ret_errno == 0){

2188

/* Lower privileges */

2189

ret_errno = lower_privileges();

2190

if(ret_errno != 0){

2191

errno = ret_errno;

2192

perror_plus("Failed to lower privileges");

2193

}

2194

}

2195

2196

/* Close the socket */

2197

ret = close(sd);

1634

2198

if(ret == -1){

1635

ret_errno = errno;

2199

perror_plus("close");

2200

}

2201

2202

if(ret_setflags == -1){

2203

errno = ioctl_errno;

1636

2204

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

2205

errno = old_errno;

1648

return ret_errno;

2206

return ioctl_errno;

1649

2207

}

2208

} else if(debug){

2209

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

2210

interface);

1650

2211

}

2212

1651

2213

/* Sleep checking until interface is running.

1652

2214

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){

2215

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

2216

if(interface_is_running(interface)){

1658

2217

break;

1659

2218

}

1660

2219

struct timespec sleeptime = { .tv_nsec = 250000000 };

1663

2222

perror_plus("nanosleep");

1664

2223

}

1665

2224

}

1666

/* Close the socket */

1667

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

1668

if(ret == -1){

1669

perror_plus("close");

2225

2226

errno = old_errno;

2227

return 0;

2228

}

2229

2230

__attribute__((nonnull, warn_unused_result))

2231

int take_down_interface(const char *const interface){

2232

int old_errno = errno;

2233

struct ifreq network;

2234

unsigned int if_index = if_nametoindex(interface);

2235

if(if_index == 0){

2236

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

2237

errno = old_errno;

2238

return ENXIO;

1670

2239

}

1671

#ifdef __linux__

1672

if(restore_loglevel){

1673

/* Restores kernel loglevel to default */

1674

ret = klogctl(7, NULL, 0);

2240

if(interface_is_up(interface)){

2241

int ret_errno = 0;

2242

int ioctl_errno = 0;

2243

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

2244

ret_errno = errno;

2245

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

2246

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

2247

errno = old_errno;

2248

return ret_errno;

2249

}

2250

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

2251

2252

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

2253

if(sd == -1){

2254

ret_errno = errno;

2255

perror_plus("socket");

2256

errno = old_errno;

2257

return ret_errno;

2258

}

2259

2260

if(debug){

2261

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

2262

interface);

2263

}

2264

2265

/* Raise privileges */

2266

ret_errno = raise_privileges();

2267

if(ret_errno != 0){

2268

errno = ret_errno;

2269

perror_plus("Failed to raise privileges");

2270

}

2271

2272

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

2273

ioctl_errno = errno;

2274

2275

/* If raise_privileges() succeeded above */

2276

if(ret_errno == 0){

2277

/* Lower privileges */

2278

ret_errno = lower_privileges();

2279

if(ret_errno != 0){

2280

errno = ret_errno;

2281

perror_plus("Failed to lower privileges");

2282

}

2283

}

2284

2285

/* Close the socket */

2286

int ret = close(sd);

1675

2287

if(ret == -1){

1676

perror_plus("klogctl");

1677

}

2288

perror_plus("close");

2289

}

2290

2291

if(ret_setflags == -1){

2292

errno = ioctl_errno;

2293

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2294

errno = old_errno;

2295

return ioctl_errno;

2296

}

2297

} else if(debug){

2298

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

2299

interface);

1678

2300

}

1679

#endif /* __linux__ */

1680

/* Lower privileges */

1681

lower_privileges();

2301

1682

2302

errno = old_errno;

1683

2303

return 0;

1684

2304

}

1685

2305

1686

2306

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

2307

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

2308

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

2309

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

2310

.current_server = NULL, .interfaces = NULL,

2311

.interfaces_size = 0 };

1687

2312

AvahiSServiceBrowser *sb = NULL;

1688

int error;

2313

error_t ret_errno;

1689

2314

int ret;

1690

2315

intmax_t tmpmax;

1691

2316

char *tmp;

1692

2317

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;

2318

char *interfaces_to_take_down = NULL;

2319

size_t interfaces_to_take_down_size = 0;

2320

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

2321

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

2322

char *tempdir = NULL;

1699

2323

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1700

2324

const char *seckey = PATHDIR "/" SECKEY;

1701

2325

const char *pubkey = PATHDIR "/" PUBKEY;

2326

const char *dh_params_file = NULL;

2327

char *interfaces_hooks = NULL;

1702

2328

1703

2329

bool gnutls_initialized = false;

1704

2330

bool gpgme_initialized = false;

1756

2382

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

1757

2383

" Diffie-Hellman key exchange",

1758

2384

.group = 2 },

2385

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

2386

.arg = "FILE",

2387

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

2388

" for the Diffie-Hellman key exchange",

2389

.group = 2 },

1759

2390

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

1760

2391

.arg = "STRING",

1761

2392

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

1795

2426

connect_to = arg;

1796

2427

break;

1797

2428

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

1798

interface = arg;

2429

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

2430

arg, (int)',');

2431

if(ret_errno != 0){

2432

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

2433

}

1799

2434

break;

1800

2435

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

1801

2436

seckey = arg;

1812

2447

}

1813

2448

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

1814

2449

break;

2450

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

2451

dh_params_file = arg;

2452

break;

1815

2453

case 130: /* --priority */

1816

2454

mc.priority = arg;

1817

2455

break;

1857

2495

.args_doc = "",

1858

2496

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

1859

2497

" passwords from a Mandos server" };

1860

ret = argp_parse(&argp, argc, argv,

1861

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1862

switch(ret){

2498

ret_errno = argp_parse(&argp, argc, argv,

2499

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2500

switch(ret_errno){

1863

2501

case 0:

1864

2502

break;

1865

2503

case ENOMEM:

1866

2504

default:

1867

errno = ret;

2505

errno = ret_errno;

1868

2506

perror_plus("argp_parse");

1869

2507

exitcode = EX_OSERR;

1870

2508

goto end;

1873

2511

goto end;

1874

2512

}

1875

2513

}

1876

2514

1877

2515

{

1878

2516

/* Work around Debian bug #633582:

1879

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

2517

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

1880

2518

1881

/* Re-raise priviliges */

1882

if(raise_privileges() == 0){

2519

/* Re-raise privileges */

2520

ret = raise_privileges();

2521

if(ret != 0){

2522

errno = ret;

2523

perror_plus("Failed to raise privileges");

2524

} else {

1883

2525

struct stat st;

1884

2526

1885

2527

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

1899

2541

}

1900

2542

}

1901

2543

}

1902

TEMP_FAILURE_RETRY(close(seckey_fd));

2544

close(seckey_fd);

1903

2545

}

1904

2546

}

1905

2547

1906

2548

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

1907

2549

int pubkey_fd = open(pubkey, O_RDONLY);

1908

2550

if(pubkey_fd == -1){

1920

2562

}

1921

2563

}

1922

2564

}

1923

TEMP_FAILURE_RETRY(close(pubkey_fd));

1924

}

1925

}

1926

2565

close(pubkey_fd);

2566

}

2567

}

2568

2569

if(dh_params_file != NULL

2570

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

2571

int dhparams_fd = open(dh_params_file, O_RDONLY);

2572

if(dhparams_fd == -1){

2573

perror_plus("open");

2574

} else {

2575

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

2576

if(ret == -1){

2577

perror_plus("fstat");

2578

} else {

2579

if(S_ISREG(st.st_mode)

2580

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

2581

ret = fchown(dhparams_fd, uid, gid);

2582

if(ret == -1){

2583

perror_plus("fchown");

2584

}

2585

}

2586

}

2587

close(dhparams_fd);

2588

}

2589

}

2590

1927

2591

/* Lower privileges */

1928

errno = 0;

1929

ret = seteuid(uid);

1930

if(ret == -1){

1931

perror_plus("seteuid");

2592

ret = lower_privileges();

2593

if(ret != 0){

2594

errno = ret;

2595

perror_plus("Failed to lower privileges");

2596

}

2597

}

2598

}

2599

2600

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

2601

{

2602

char *interface = NULL;

2603

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

2604

interface))){

2605

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

2606

and if_nametoindex(interface) == 0){

2607

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

2608

fprintf_plus(stderr, "Not using nonexisting interface"

2609

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

2610

}

2611

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

2612

interface = NULL;

1932

2613

}

1933

2614

}

1934

2615

}

1935

2616

1936

2617

/* Run network hooks */

1937

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

1938

goto end;

2618

{

2619

if(mc.interfaces != NULL){

2620

interfaces_hooks = malloc(mc.interfaces_size);

2621

if(interfaces_hooks == NULL){

2622

perror_plus("malloc");

2623

goto end;

2624

}

2625

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

2626

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

2627

}

2628

run_network_hooks("start", interfaces_hooks != NULL ?

2629

interfaces_hooks : "", delay);

1939

2630

}

1940

2631

1941

2632

if(not debug){

1942

2633

avahi_set_log_function(empty_log);

1943

2634

}

1944

2635

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

2636

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

1978

2637

from the signal handler */

1979

2638

/* Initialize the pseudo-RNG for Avahi */

1980

2639

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

1981

mc.simple_poll = avahi_simple_poll_new();

1982

if(mc.simple_poll == NULL){

2640

simple_poll = avahi_simple_poll_new();

2641

if(simple_poll == NULL){

1983

2642

fprintf_plus(stderr,

1984

2643

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

1985

2644

exitcode = EX_UNAVAILABLE;

2049

2708

}

2050

2709

}

2051

2710

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

}

2711

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

2712

if(mc.interfaces == NULL){

2713

struct dirent **direntries = NULL;

2714

/* Look for any good interfaces */

2715

ret = scandir(sys_class_net, &direntries, good_interface,

2716

alphasort);

2717

if(ret >= 1){

2718

/* Add all found interfaces to interfaces list */

2719

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

2720

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

2721

direntries[i]->d_name);

2722

if(ret_errno != 0){

2723

errno = ret_errno;

2724

perror_plus("argz_add");

2725

free(direntries[i]);

2726

continue;

2727

}

2728

if(debug){

2729

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

2730

direntries[i]->d_name);

2731

}

2732

free(direntries[i]);

2733

}

2734

free(direntries);

2735

} else {

2736

if(ret == 0){

2737

free(direntries);

2738

}

2739

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

2740

exitcode = EXIT_FAILURE;

2741

goto end;

2742

}

2743

}

2744

2745

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

2746

{

2747

char *interface = NULL;

2748

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

2749

interface))){

2750

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

2751

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

2752

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

2753

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

2754

interface);

2755

interface = NULL;

2756

while((interface = argz_next(mc.interfaces,

2757

mc.interfaces_size, interface))){

2758

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

2759

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

2760

interface);

2761

interface = NULL;

2762

}

2763

}

2764

break;

2765

}

2766

bool interface_was_up = interface_is_up(interface);

2767

errno = bring_up_interface(interface, delay);

2768

if(not interface_was_up){

2769

if(errno != 0){

2770

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

2771

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

2772

} else {

2773

errno = argz_add(&interfaces_to_take_down,

2774

&interfaces_to_take_down_size,

2775

interface);

2776

if(errno != 0){

2777

perror_plus("argz_add");

2778

}

2779

}

2780

}

2781

}

2782

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

2783

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

2784

}

2785

}

2786

2787

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

2788

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

2789

if(debug){

2790

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

2791

mc.interfaces);

2792

}

2793

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

2059

2794

}

2060

2795

2061

2796

if(quit_now){

2062

2797

goto end;

2063

2798

}

2064

2799

2065

ret = init_gnutls_global(pubkey, seckey);

2800

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

2066

2801

if(ret == -1){

2067

2802

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

2068

2803

exitcode = EX_UNAVAILABLE;

2075

2810

goto end;

2076

2811

}

2077

2812

2078

if(mkdtemp(tempdir) == NULL){

2813

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

2814

tempdir = mkdtemp(run_tempdir);

2815

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

2816

if(debug){

2817

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

2818

run_tempdir, old_tempdir);

2819

}

2820

tempdir = mkdtemp(old_tempdir);

2821

}

2822

if(tempdir == NULL){

2079

2823

perror_plus("mkdtemp");

2080

2824

goto end;

2081

2825

}

2082

tempdir_created = true;

2083

2826

2084

2827

if(quit_now){

2085

2828

goto end;

2086

2829

}

2087

2830

2088

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

2831

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

2089

2832

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

2090

2833

exitcode = EX_UNAVAILABLE;

2091

2834

goto end;

2112

2855

goto end;

2113

2856

}

2114

2857

2115

uint16_t port;

2858

in_port_t port;

2116

2859

errno = 0;

2117

2860

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

2118

2861

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

2119

or tmpmax != (uint16_t)tmpmax){

2862

or tmpmax != (in_port_t)tmpmax){

2120

2863

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

2121

2864

exitcode = EX_USAGE;

2122

2865

goto end;

2123

2866

}

2124

2867

2125

2868

if(quit_now){

2126

2869

goto end;

2127

2870

}

2128

2871

2129

port = (uint16_t)tmpmax;

2872

port = (in_port_t)tmpmax;

2130

2873

*address = '\0';

2131

2874

/* Colon in address indicates IPv6 */

2132

2875

int af;

2148

2891

}

2149

2892

2150

2893

while(not quit_now){

2151

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

2894

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

2895

&mc);

2152

2896

if(quit_now or ret == 0){

2153

2897

break;

2154

2898

}

2156

2900

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

2157

2901

(int)retry_interval);

2158

2902

}

2159

sleep((int)retry_interval);

2903

sleep((unsigned int)retry_interval);

2160

2904

}

2161

2905

2162

if (not quit_now){

2906

if(not quit_now){

2163

2907

exitcode = EXIT_SUCCESS;

2164

2908

}

2165

2909

2180

2924

config.publish_domain = 0;

2181

2925

2182

2926

/* Allocate a new server */

2183

mc.server = avahi_server_new(avahi_simple_poll_get

2184

(mc.simple_poll), &config, NULL,

2185

NULL, &error);

2927

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2928

&config, NULL, NULL, &ret);

2186

2929

2187

2930

/* Free the Avahi configuration data */

2188

2931

avahi_server_config_free(&config);

2191

2934

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

2192

2935

if(mc.server == NULL){

2193

2936

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

2194

avahi_strerror(error));

2937

avahi_strerror(ret));

2195

2938

exitcode = EX_UNAVAILABLE;

2196

2939

goto end;

2197

2940

}

2203

2946

/* Create the Avahi service browser */

2204

2947

sb = avahi_s_service_browser_new(mc.server, if_index,

2205

2948

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2206

NULL, 0, browse_callback, NULL);

2949

NULL, 0, browse_callback,

2950

(void *)&mc);

2207

2951

if(sb == NULL){

2208

2952

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

2209

2953

avahi_strerror(avahi_server_errno(mc.server)));

2220

2964

if(debug){

2221

2965

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

2222

2966

}

2223

2224

ret = avahi_loop_with_timeout(mc.simple_poll,

2225

(int)(retry_interval * 1000));

2967

2968

ret = avahi_loop_with_timeout(simple_poll,

2969

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

2226

2970

if(debug){

2227

2971

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

2228

2972

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

2231

2975

end:

2232

2976

2233

2977

if(debug){

2234

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

2978

if(signal_received){

2979

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

2980

argv[0], signal_received,

2981

strsignal(signal_received));

2982

} else {

2983

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

2984

}

2235

2985

}

2236

2986

2237

2987

/* Cleanup things */

2988

free(mc.interfaces);

2989

2238

2990

if(sb != NULL)

2239

2991

avahi_s_service_browser_free(sb);

2240

2992

2241

2993

if(mc.server != NULL)

2242

2994

avahi_server_free(mc.server);

2243

2995

2244

if(mc.simple_poll != NULL)

2245

avahi_simple_poll_free(mc.simple_poll);

2996

if(simple_poll != NULL)

2997

avahi_simple_poll_free(simple_poll);

2246

2998

2247

2999

if(gnutls_initialized){

2248

3000

gnutls_certificate_free_credentials(mc.cred);

2249

gnutls_global_deinit();

2250

3001

gnutls_dh_params_deinit(mc.dh_params);

2251

3002

}

2252

3003

2260

3011

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

2261

3012

while(mc.current_server != NULL){

2262

3013

server *next = mc.current_server->next;

3014

#ifdef __GNUC__

3015

#pragma GCC diagnostic push

3016

#pragma GCC diagnostic ignored "-Wcast-qual"

3017

#endif

3018

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

3019

#ifdef __GNUC__

3020

#pragma GCC diagnostic pop

3021

#endif

2263

3022

free(mc.current_server);

2264

3023

mc.current_server = next;

2265

3024

}

2266

3025

}

2267

3026

2268

/* Run network hooks */

2269

run_network_hooks("stop", interface, delay);

2270

2271

/* Re-raise priviliges */

3027

/* Re-raise privileges */

2272

3028

{

2273

raise_privileges();

3029

ret = raise_privileges();

3030

if(ret != 0){

3031

errno = ret;

3032

perror_plus("Failed to raise privileges");

3033

} else {

3034

3035

/* Run network hooks */

3036

run_network_hooks("stop", interfaces_hooks != NULL ?

3037

interfaces_hooks : "", delay);

3038

3039

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

3040

{

3041

char *interface = NULL;

3042

while((interface = argz_next(interfaces_to_take_down,

3043

interfaces_to_take_down_size,

3044

interface))){

3045

ret = take_down_interface(interface);

3046

if(ret != 0){

3047

errno = ret;

3048

perror_plus("Failed to take down interface");

3049

}

3050

}

3051

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

3052

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

3053

" down\n");

3054

}

3055

}

3056

}

2274

3057

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

}

3058

ret = lower_privileges_permanently();

3059

if(ret != 0){

3060

errno = ret;

3061

perror_plus("Failed to lower privileges permanently");

2291

3062

}

2292

3063

}

2293

/* Lower privileges permanently */

2294

errno = 0;

2295

ret = setuid(uid);

2296

if(ret == -1){

2297

perror_plus("setuid");

3064

3065

free(interfaces_to_take_down);

3066

free(interfaces_hooks);

3067

3068

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

3069

uintmax_t level){

3070

struct dirent **direntries = NULL;

3071

int dret;

3072

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

3073

O_RDONLY

3074

| O_NOFOLLOW

3075

| O_DIRECTORY

3076

| O_PATH));

3077

if(dir_fd == -1){

3078

perror_plus("open");

3079

return;

3080

}

3081

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

3082

notdotentries, alphasort);

3083

if(numentries >= 0){

3084

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

3085

if(debug){

3086

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

3087

dirname, direntries[i]->d_name);

3088

}

3089

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

3090

if(dret == -1){

3091

if(errno == EISDIR){

3092

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

3093

AT_REMOVEDIR);

3094

}

3095

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

3096

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

3097

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

3098

/* Recurse only in this special case */

3099

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

3100

dret = 0;

3101

}

3102

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

3103

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

3104

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

3105

}

3106

}

3107

free(direntries[i]);

3108

}

3109

3110

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

3111

free(direntries);

3112

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3113

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

3114

perror_plus("rmdir");

3115

}

3116

} else {

3117

perror_plus("scandirat");

3118

}

3119

close(dir_fd);

2298

3120

}

2299

3121

2300

3122

/* 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

}

3123

if(tempdir != NULL){

3124

clean_dir_at(-1, tempdir, 0);

2334

3125

}

2335

3126

2336

3127

if(quit_now){