/mandos/release : revision 237.7.104

9

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

10

*

11

* Everything else is

12

13

14

*

15

* This file is part of Mandos.

16

*

17

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

18

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

19

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

20

* (at your option) any later version.

21

*

22

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

12

13

14

*

15

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

16

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

17

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

18

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

19

*

20

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

23

21

* WITHOUT ANY WARRANTY; without even the implied warranty of

24

22

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

25

23

* General Public License for more details.

26

24

*

27

25

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

28

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

26

* along with this program. If not, see

27

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

29

28

*

30

29

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

31

30

*/

33

32

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

34

33

#ifndef _LARGEFILE_SOURCE

35

34

#define _LARGEFILE_SOURCE

36

#endif /* not _LARGEFILE_SOURCE */

35

#endif

37

36

#ifndef _FILE_OFFSET_BITS

38

37

#define _FILE_OFFSET_BITS 64

39

#endif /* not _FILE_OFFSET_BITS */

38

#endif

40

39

41

40

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

42

41

43

42

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

44

stdout, ferror() */

45

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

43

stdout, ferror(), remove() */

44

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

46

45

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

47

46

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

48

47

strtof(), abort() */

49

48

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

50

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

51

asprintf(), strncpy(), strsignal()

52

*/

49

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

50

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

53

51

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

54

52

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

55

53

sockaddr_in6, PF_INET6,

57

55

opendir(), DIR */

58

56

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

59

57

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

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

58

inet_pton(), connect() */

59

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

63

60

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

64

61

*/

65

62

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

66

63

strtoimax() */

67

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

68

EAI_SYSTEM, ENETUNREACH,

69

EHOSTUNREACH, ECONNREFUSED, EPROTO,

70

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

71

ENOTEMPTY,

64

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

65

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

72

66

program_invocation_short_name */

73

67

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

74

68

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

79

73

*/

80

74

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

81

75

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

82

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

83

unlinkat() */

84

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

76

setgid(), pause(), _exit() */

77

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

85

78

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

86

79

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

87

80

argp_state, struct argp,

95

88

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

96

89

WEXITSTATUS(), WTERMSIG() */

97

90

#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() */

104

91

105

92

#ifdef __linux__

106

93

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

123

110

gnutls_*

124

111

init_gnutls_session(),

125

112

GNUTLS_* */

126

#if GNUTLS_VERSION_NUMBER < 0x030600

127

113

#include <gnutls/openpgp.h>

128

114

/* gnutls_certificate_set_openpgp_key_file(),

129

115

GNUTLS_OPENPGP_FMT_BASE64 */

130

#elif GNUTLS_VERSION_NUMBER >= 0x030606

131

#include <gnutls/x509.h> /* gnutls_pkcs_encrypt_flags_t,

132

GNUTLS_PKCS_PLAIN,

133

GNUTLS_PKCS_NULL_PASSWORD */

134

#endif

135

116

136

117

/* GPGME */

137

118

#include <gpgme.h> /* All GPGME types, constants and

145

126

#define PATHDIR "/conf/conf.d/mandos"

146

127

#define SECKEY "seckey.txt"

147

128

#define PUBKEY "pubkey.txt"

148

#define TLS_PRIVKEY "tls-privkey.pem"

149

#define TLS_PUBKEY "tls-pubkey.pem"

150

129

#define HOOKDIR "/lib/mandos/network-hooks.d"

151

130

152

131

bool debug = false;

156

135

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

157

136

char *connect_to = NULL;

158

137

const char *hookdir = HOOKDIR;

159

int hookdir_fd = -1;

160

uid_t uid = 65534;

161

gid_t gid = 65534;

162

138

163

139

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

164

140

typedef struct server{

165

141

const char *ip;

166

in_port_t port;

142

uint16_t port;

167

143

AvahiIfIndex if_index;

168

144

int af;

169

145

struct timespec last_seen;

173

149

174

150

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

175

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

176

153

AvahiServer *server;

177

154

gnutls_certificate_credentials_t cred;

178

155

unsigned int dh_bits;

180

157

const char *priority;

181

158

gpgme_ctx_t ctx;

182

159

server *current_server;

183

char *interfaces;

184

size_t interfaces_size;

185

160

} mandos_context;

186

161

187

/* global so signal handler can reach it*/

188

AvahiSimplePoll *simple_poll;

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

189

167

190

168

sig_atomic_t quit_now = 0;

191

169

int signal_received = 0;

199

177

perror(print_text);

200

178

}

201

179

202

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

180

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

203

181

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

204

182

va_list ap;

205

183

va_start (ap, format);

206

184

207

185

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

208

186

program_invocation_short_name));

209

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

187

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

210

188

}

211

189

212

190

/*

214

192

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

215

193

* "buffer_length" is how much is already used.

216

194

*/

217

__attribute__((nonnull, warn_unused_result))

218

195

size_t incbuffer(char **buffer, size_t buffer_length,

219

196

size_t buffer_capacity){

220

197

if(buffer_length + BUFFER_SIZE > buffer_capacity){

221

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

222

if(new_buf == NULL){

223

int old_errno = errno;

224

free(*buffer);

225

errno = old_errno;

226

*buffer = NULL;

198

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

199

if(buffer == NULL){

227

200

return 0;

228

201

}

229

*buffer = new_buf;

230

202

buffer_capacity += BUFFER_SIZE;

231

203

}

232

204

return buffer_capacity;

233

205

}

234

206

235

207

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

236

__attribute__((nonnull, warn_unused_result))

237

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

238

int af, server **current_server){

208

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

209

int af){

239

210

int ret;

240

211

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

241

212

if(new_server == NULL){

248

219

.af = af };

249

220

if(new_server->ip == NULL){

250

221

perror_plus("strdup");

251

free(new_server);

252

return false;

253

}

254

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

255

if(ret == -1){

256

perror_plus("clock_gettime");

257

#ifdef __GNUC__

258

#pragma GCC diagnostic push

259

#pragma GCC diagnostic ignored "-Wcast-qual"

260

#endif

261

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

262

#ifdef __GNUC__

263

#pragma GCC diagnostic pop

264

#endif

265

free(new_server);

266

222

return false;

267

223

}

268

224

/* Special case of first server */

269

if(*current_server == NULL){

225

if (mc.current_server == NULL){

270

226

new_server->next = new_server;

271

227

new_server->prev = new_server;

272

*current_server = new_server;

228

mc.current_server = new_server;

229

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

273

230

} else {

274

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

275

new_server->next = *current_server;

276

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

231

new_server->next = mc.current_server;

232

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

277

233

new_server->prev->next = new_server;

278

(*current_server)->prev = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

279

240

}

280

241

return true;

281

242

}

282

243

283

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

286

int old_errno = errno;

287

int ret = 0;

288

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

289

ret = errno;

290

}

291

errno = old_errno;

292

return ret;

293

}

294

295

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

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

298

int old_errno = errno;

299

int ret = raise_privileges();

300

if(ret != 0){

301

errno = old_errno;

302

return ret;

303

}

304

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

305

ret = errno;

306

}

307

errno = old_errno;

308

return ret;

309

}

310

311

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

312

__attribute__((warn_unused_result))

313

int lower_privileges(void){

314

int old_errno = errno;

315

int ret = 0;

316

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

317

ret = errno;

318

}

319

errno = old_errno;

320

return ret;

321

}

322

323

/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

325

int lower_privileges_permanently(void){

326

int old_errno = errno;

327

int ret = 0;

328

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

329

ret = errno;

330

}

331

errno = old_errno;

332

return ret;

333

}

334

335

244

/*

336

245

* Initialize GPGME.

337

246

*/

338

__attribute__((nonnull, warn_unused_result))

339

static bool init_gpgme(const char * const seckey,

340

const char * const pubkey,

341

const char * const tempdir,

342

mandos_context *mc){

247

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

248

const char *tempdir){

343

249

gpgme_error_t rc;

344

250

gpgme_engine_info_t engine_info;

345

251

252

346

253

/*

347

254

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

348

255

*/

349

bool import_key(const char * const filename){

256

bool import_key(const char *filename){

350

257

int ret;

351

258

int fd;

352

259

gpgme_data_t pgp_data;

357

264

return false;

358

265

}

359

266

360

/* Workaround for systems without a real-time clock; see also

361

Debian bug #894495: <https://bugs.debian.org/894495> */

362

do {

363

{

364

time_t currtime = time(NULL);

365

if(currtime != (time_t)-1){

366

struct tm tm;

367

if(gmtime_r(&currtime, &tm) == NULL) {

368

perror_plus("gmtime_r");

369

break;

370

}

371

if(tm.tm_year != 70 or tm.tm_mon != 0){

372

break;

373

}

374

if(debug){

375

fprintf_plus(stderr, "System clock is January 1970");

376

}

377

} else {

378

if(debug){

379

fprintf_plus(stderr, "System clock is invalid");

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

time_t keytime = keystat.st_mtim.tv_sec;

400

if(stime(&keytime) != 0){

401

perror_plus("stime");

402

}

403

ret = lower_privileges();

404

if(ret != 0){

405

errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

410

267

rc = gpgme_data_new_from_fd(&pgp_data, fd);

411

268

if(rc != GPG_ERR_NO_ERROR){

412

269

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

414

271

return false;

415

272

}

416

273

417

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

274

rc = gpgme_op_import(mc.ctx, pgp_data);

418

275

if(rc != GPG_ERR_NO_ERROR){

419

276

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

420

277

gpgme_strsource(rc), gpgme_strerror(rc));

421

278

return false;

422

279

}

423

{

424

gpgme_import_result_t import_result

425

= gpgme_op_import_result(mc->ctx);

426

if((import_result->imported < 1

427

or import_result->not_imported > 0)

428

and import_result->unchanged == 0){

429

fprintf_plus(stderr, "bad gpgme_op_import_results:\n");

430

fprintf_plus(stderr,

431

"The total number of considered keys: %d\n",

432

import_result->considered);

433

fprintf_plus(stderr,

434

"The number of keys without user ID: %d\n",

435

import_result->no_user_id);

436

fprintf_plus(stderr,

437

"The total number of imported keys: %d\n",

438

import_result->imported);

439

fprintf_plus(stderr, "The number of imported RSA keys: %d\n",

440

import_result->imported_rsa);

441

fprintf_plus(stderr, "The number of unchanged keys: %d\n",

442

import_result->unchanged);

443

fprintf_plus(stderr, "The number of new user IDs: %d\n",

444

import_result->new_user_ids);

445

fprintf_plus(stderr, "The number of new sub keys: %d\n",

446

import_result->new_sub_keys);

447

fprintf_plus(stderr, "The number of new signatures: %d\n",

448

import_result->new_signatures);

449

fprintf_plus(stderr, "The number of new revocations: %d\n",

450

import_result->new_revocations);

451

fprintf_plus(stderr,

452

"The total number of secret keys read: %d\n",

453

import_result->secret_read);

454

fprintf_plus(stderr,

455

"The number of imported secret keys: %d\n",

456

import_result->secret_imported);

457

fprintf_plus(stderr,

458

"The number of unchanged secret keys: %d\n",

459

import_result->secret_unchanged);

460

fprintf_plus(stderr, "The number of keys not imported: %d\n",

461

import_result->not_imported);

462

for(gpgme_import_status_t import_status

463

= import_result->imports;

464

import_status != NULL;

465

import_status = import_status->next){

466

fprintf_plus(stderr, "Import status for key: %s\n",

467

import_status->fpr);

468

if(import_status->result != GPG_ERR_NO_ERROR){

469

fprintf_plus(stderr, "Import result: %s: %s\n",

470

gpgme_strsource(import_status->result),

471

gpgme_strerror(import_status->result));

472

}

473

fprintf_plus(stderr, "Key status:\n");

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_NEW

476

? "The key was new.\n"

477

: "The key was not new.\n");

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_UID

480

? "The key contained new user IDs.\n"

481

: "The key did not contain new user IDs.\n");

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SIG

484

? "The key contained new signatures.\n"

485

: "The key did not contain new signatures.\n");

486

fprintf_plus(stderr,

487

import_status->status & GPGME_IMPORT_SUBKEY

488

? "The key contained new sub keys.\n"

489

: "The key did not contain new sub keys.\n");

490

fprintf_plus(stderr,

491

import_status->status & GPGME_IMPORT_SECRET

492

? "The key contained a secret key.\n"

493

: "The key did not contain a secret key.\n");

494

}

495

return false;

496

}

497

}

498

280

499

ret = close(fd);

281

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

500

282

if(ret == -1){

501

283

perror_plus("close");

502

284

}

539

321

}

540

322

541

323

/* Create new GPGME "context" */

542

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

324

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

543

325

if(rc != GPG_ERR_NO_ERROR){

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

326

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

327

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

328

gpgme_strerror(rc));

546

329

return false;

547

330

}

548

331

557

340

* Decrypt OpenPGP data.

558

341

* Returns -1 on error

559

342

*/

560

__attribute__((nonnull, warn_unused_result))

561

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

562

344

size_t crypto_size,

563

char **plaintext,

564

mandos_context *mc){

345

char **plaintext){

565

346

gpgme_data_t dh_crypto, dh_plain;

566

347

gpgme_error_t rc;

567

348

ssize_t ret;

584

365

/* Create new empty GPGME data buffer for the plaintext */

585

366

rc = gpgme_data_new(&dh_plain);

586

367

if(rc != GPG_ERR_NO_ERROR){

587

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

368

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

369

"bad gpgme_data_new: %s: %s\n",

588

370

gpgme_strsource(rc), gpgme_strerror(rc));

589

371

gpgme_data_release(dh_crypto);

590

372

return -1;

592

374

593

375

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

594

376

data buffer */

595

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

377

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

596

378

if(rc != GPG_ERR_NO_ERROR){

597

379

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

598

380

gpgme_strsource(rc), gpgme_strerror(rc));

599

381

plaintext_length = -1;

600

382

if(debug){

601

383

gpgme_decrypt_result_t result;

602

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

603

385

if(result == NULL){

604

386

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

605

387

} else {

606

if(result->unsupported_algorithm != NULL) {

607

fprintf_plus(stderr, "Unsupported algorithm: %s\n",

608

result->unsupported_algorithm);

609

}

610

fprintf_plus(stderr, "Wrong key usage: %s\n",

611

result->wrong_key_usage ? "Yes" : "No");

388

fprintf_plus(stderr, "Unsupported algorithm: %s\n",

389

result->unsupported_algorithm);

390

fprintf_plus(stderr, "Wrong key usage: %u\n",

391

result->wrong_key_usage);

612

392

if(result->file_name != NULL){

613

393

fprintf_plus(stderr, "File name: %s\n", result->file_name);

614

394

}

615

616

for(gpgme_recipient_t r = result->recipients; r != NULL;

617

r = r->next){

395

gpgme_recipient_t recipient;

396

recipient = result->recipients;

397

while(recipient != NULL){

618

398

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

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

621

402

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

622

r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

405

recipient = recipient->next;

623

406

}

624

407

}

625

408

}

681

464

return plaintext_length;

682

465

}

683

466

684

__attribute__((warn_unused_result, const))

685

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

686

if(str == NULL)

687

return "(unknown)";

688

return str;

689

}

690

691

__attribute__((warn_unused_result))

692

static const char *safer_gnutls_strerror(int value){

693

const char *ret = gnutls_strerror(value);

694

return safe_string(ret);

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

470

if(ret == NULL)

471

ret = "(unknown)";

472

return ret;

695

473

}

696

474

697

475

/* GnuTLS log function callback */

698

__attribute__((nonnull))

699

476

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

700

477

const char* string){

701

478

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

702

479

}

703

480

704

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

705

481

static int init_gnutls_global(const char *pubkeyfilename,

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

mandos_context *mc){

482

const char *seckeyfilename){

709

483

int ret;

710

484

711

485

if(debug){

712

486

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

713

487

}

714

488

489

ret = gnutls_global_init();

490

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

493

return -1;

494

}

495

715

496

if(debug){

716

497

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

717

498

* - GnuTLS manual

721

502

}

722

503

723

504

/* OpenPGP credentials */

724

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

725

506

if(ret != GNUTLS_E_SUCCESS){

726

507

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

727

508

safer_gnutls_strerror(ret));

509

gnutls_global_deinit();

728

510

return -1;

729

511

}

730

512

731

513

if(debug){

732

fprintf_plus(stderr, "Attempting to use public key %s and"

733

" private key %s as GnuTLS credentials\n",

514

fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"

515

" secret key %s as GnuTLS credentials\n",

734

516

pubkeyfilename,

735

517

seckeyfilename);

736

518

}

737

519

738

#if GNUTLS_VERSION_NUMBER >= 0x030606

739

ret = gnutls_certificate_set_rawpk_key_file

740

(mc->cred, pubkeyfilename, seckeyfilename,

741

GNUTLS_X509_FMT_PEM, /* format */

742

NULL, /* pass */

743

/* key_usage */

744

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

745

NULL, /* names */

746

0, /* names_length */

747

/* privkey_flags */

748

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

749

0); /* pkcs11_flags */

750

#elif GNUTLS_VERSION_NUMBER < 0x030600

751

520

ret = gnutls_certificate_set_openpgp_key_file

752

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

753

522

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

756

#endif

757

523

if(ret != GNUTLS_E_SUCCESS){

758

524

fprintf_plus(stderr,

759

"Error[%d] while reading the key pair ('%s',"

525

"Error[%d] while reading the OpenPGP key pair ('%s',"

760

526

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

761

527

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

762

528

safer_gnutls_strerror(ret));

764

530

}

765

531

766

532

/* GnuTLS server initialization */

767

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

768

534

if(ret != GNUTLS_E_SUCCESS){

769

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

770

536

" initialization: %s\n",

771

537

safer_gnutls_strerror(ret));

772

538

goto globalfail;

773

539

}

774

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

775

if(dhparamsfilename != NULL){

776

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

777

do {

778

int dhpfile = open(dhparamsfilename, O_RDONLY);

779

if(dhpfile == -1){

780

perror_plus("open");

781

dhparamsfilename = NULL;

782

break;

783

}

784

size_t params_capacity = 0;

785

while(true){

786

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

787

(size_t)params.size,

788

(size_t)params_capacity);

789

if(params_capacity == 0){

790

perror_plus("incbuffer");

791

free(params.data);

792

params.data = NULL;

793

dhparamsfilename = NULL;

794

break;

795

}

796

ssize_t bytes_read = read(dhpfile,

797

params.data + params.size,

798

BUFFER_SIZE);

799

/* EOF */

800

if(bytes_read == 0){

801

break;

802

}

803

/* check bytes_read for failure */

804

if(bytes_read < 0){

805

perror_plus("read");

806

free(params.data);

807

params.data = NULL;

808

dhparamsfilename = NULL;

809

break;

810

}

811

params.size += (unsigned int)bytes_read;

812

}

813

ret = close(dhpfile);

814

if(ret == -1){

815

perror_plus("close");

816

}

817

if(params.data == NULL){

818

dhparamsfilename = NULL;

819

}

820

if(dhparamsfilename == NULL){

821

break;

822

}

823

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

824

GNUTLS_X509_FMT_PEM);

825

if(ret != GNUTLS_E_SUCCESS){

826

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

827

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

828

safer_gnutls_strerror(ret));

829

dhparamsfilename = NULL;

830

}

831

free(params.data);

832

} while(false);

833

}

834

if(dhparamsfilename == NULL){

835

if(mc->dh_bits == 0){

836

#if GNUTLS_VERSION_NUMBER < 0x030600

837

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

838

/* Try to read the private key file */

839

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

840

do {

841

int secfile = open(seckeyfilename, O_RDONLY);

842

if(secfile == -1){

843

perror_plus("open");

844

break;

845

}

846

size_t buffer_capacity = 0;

847

while(true){

848

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

849

(size_t)buffer.size,

850

(size_t)buffer_capacity);

851

if(buffer_capacity == 0){

852

perror_plus("incbuffer");

853

free(buffer.data);

854

buffer.data = NULL;

855

break;

856

}

857

ssize_t bytes_read = read(secfile,

858

buffer.data + buffer.size,

859

BUFFER_SIZE);

860

/* EOF */

861

if(bytes_read == 0){

862

break;

863

}

864

/* check bytes_read for failure */

865

if(bytes_read < 0){

866

perror_plus("read");

867

free(buffer.data);

868

buffer.data = NULL;

869

break;

870

}

871

buffer.size += (unsigned int)bytes_read;

872

}

873

close(secfile);

874

} while(false);

875

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

876

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

877

if(buffer.data != NULL){

878

{

879

gnutls_openpgp_privkey_t privkey = NULL;

880

ret = gnutls_openpgp_privkey_init(&privkey);

881

if(ret != GNUTLS_E_SUCCESS){

882

fprintf_plus(stderr, "Error initializing OpenPGP key"

883

" structure: %s",

884

safer_gnutls_strerror(ret));

885

free(buffer.data);

886

buffer.data = NULL;

887

} else {

888

ret = gnutls_openpgp_privkey_import

889

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

890

if(ret != GNUTLS_E_SUCCESS){

891

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

892

safer_gnutls_strerror(ret));

893

privkey = NULL;

894

}

895

free(buffer.data);

896

buffer.data = NULL;

897

if(privkey != NULL){

898

/* Use private key to suggest an appropriate

899

sec_param */

900

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

901

gnutls_openpgp_privkey_deinit(privkey);

902

if(debug){

903

fprintf_plus(stderr, "This OpenPGP key implies using"

904

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

905

safe_string(gnutls_sec_param_get_name

906

(sec_param)));

907

}

908

}

909

}

910

}

911

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

912

/* Err on the side of caution */

913

sec_param = GNUTLS_SEC_PARAM_ULTRA;

914

if(debug){

915

fprintf_plus(stderr, "Falling back to security parameter"

916

" \"%s\"\n",

917

safe_string(gnutls_sec_param_get_name

918

(sec_param)));

919

}

920

}

921

}

922

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

923

if(uret != 0){

924

mc->dh_bits = uret;

925

if(debug){

926

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

927

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

928

safe_string(gnutls_sec_param_get_name

929

(sec_param)),

930

mc->dh_bits);

931

}

932

} else {

933

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

934

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

935

safe_string(gnutls_sec_param_get_name

936

(sec_param)),

937

safer_gnutls_strerror(ret));

938

goto globalfail;

939

}

940

#endif

941

} else { /* dh_bits != 0 */

942

if(debug){

943

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

944

mc->dh_bits);

945

}

946

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

947

if(ret != GNUTLS_E_SUCCESS){

948

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

949

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

950

safer_gnutls_strerror(ret));

951

goto globalfail;

952

}

953

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

954

}

955

}

540

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

541

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

544

goto globalfail;

545

}

546

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

956

548

957

549

return 0;

958

550

959

551

globalfail:

960

552

961

gnutls_certificate_free_credentials(mc->cred);

962

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_certificate_free_credentials(mc.cred);

554

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

963

556

return -1;

964

557

}

965

558

966

__attribute__((nonnull, warn_unused_result))

967

static int init_gnutls_session(gnutls_session_t *session,

968

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

969

560

int ret;

970

561

/* GnuTLS session creation */

971

562

do {

972

ret = gnutls_init(session, (GNUTLS_SERVER

973

#if GNUTLS_VERSION_NUMBER >= 0x030506

974

| GNUTLS_NO_TICKETS

975

#endif

976

#if GNUTLS_VERSION_NUMBER >= 0x030606

977

| GNUTLS_ENABLE_RAWPK

978

#endif

979

));

563

ret = gnutls_init(session, GNUTLS_SERVER);

980

564

if(quit_now){

981

565

return -1;

982

566

}

990

574

{

991

575

const char *err;

992

576

do {

993

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

577

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

994

578

if(quit_now){

995

579

gnutls_deinit(*session);

996

580

return -1;

1007

591

1008

592

do {

1009

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1010

mc->cred);

594

mc.cred);

1011

595

if(quit_now){

1012

596

gnutls_deinit(*session);

1013

597

return -1;

1023

607

/* ignore client certificate if any. */

1024

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1025

609

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

611

1026

612

return 0;

1027

613

}

1028

614

1030

616

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

1031

617

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

1032

618

1033

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

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool add_delete_local_route(const bool add,

1036

const char *address,

1037

AvahiIfIndex if_index){

1038

int ret;

1039

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

1040

char add_arg[] = "add";

1041

char delete_arg[] = "delete";

1042

char debug_flag[] = "--debug";

1043

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1044

if(pluginhelperdir == NULL){

1045

if(debug){

1046

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1047

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

1048

}

1049

return false;

1050

}

1051

1052

char interface[IF_NAMESIZE];

1053

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

1054

perror_plus("if_indextoname");

1055

return false;

1056

}

1057

1058

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

1059

if(devnull == -1){

1060

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

1061

return false;

1062

}

1063

pid_t pid = fork();

1064

if(pid == 0){

1065

/* Child */

1066

/* Raise privileges */

1067

errno = raise_privileges_permanently();

1068

if(errno != 0){

1069

perror_plus("Failed to raise privileges");

1070

/* _exit(EX_NOPERM); */

1071

} else {

1072

/* Set group */

1073

errno = 0;

1074

ret = setgid(0);

1075

if(ret == -1){

1076

perror_plus("setgid");

1077

close(devnull);

1078

_exit(EX_NOPERM);

1079

}

1080

/* Reset supplementary groups */

1081

errno = 0;

1082

ret = setgroups(0, NULL);

1083

if(ret == -1){

1084

perror_plus("setgroups");

1085

close(devnull);

1086

_exit(EX_NOPERM);

1087

}

1088

}

1089

ret = dup2(devnull, STDIN_FILENO);

1090

if(ret == -1){

1091

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

1092

close(devnull);

1093

_exit(EX_OSERR);

1094

}

1095

ret = close(devnull);

1096

if(ret == -1){

1097

perror_plus("close");

1098

}

1099

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1100

if(ret == -1){

1101

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

1102

_exit(EX_OSERR);

1103

}

1104

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

1105

O_RDONLY

1106

| O_DIRECTORY

1107

| O_PATH

1108

| O_CLOEXEC));

1109

if(helperdir_fd == -1){

1110

perror_plus("open");

1111

_exit(EX_UNAVAILABLE);

1112

}

1113

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

1114

helper, O_RDONLY));

1115

if(helper_fd == -1){

1116

perror_plus("openat");

1117

close(helperdir_fd);

1118

_exit(EX_UNAVAILABLE);

1119

}

1120

close(helperdir_fd);

1121

#ifdef __GNUC__

1122

#pragma GCC diagnostic push

1123

#pragma GCC diagnostic ignored "-Wcast-qual"

1124

#endif

1125

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

1126

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

1127

interface, debug ? debug_flag : NULL, NULL },

1128

environ) == -1){

1129

#ifdef __GNUC__

1130

#pragma GCC diagnostic pop

1131

#endif

1132

perror_plus("fexecve");

1133

_exit(EXIT_FAILURE);

1134

}

1135

}

1136

if(pid == -1){

1137

perror_plus("fork");

1138

close(devnull);

1139

return false;

1140

}

1141

ret = close(devnull);

1142

if(ret == -1){

1143

perror_plus("close");

1144

}

1145

int status;

1146

pid_t pret = -1;

1147

errno = 0;

1148

do {

1149

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

1150

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

1151

int errno_raising = 0;

1152

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

1153

errno_raising = errno;

1154

perror_plus("Failed to raise privileges in order to"

1155

" kill helper program");

1156

}

1157

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

1158

perror_plus("kill");

1159

}

1160

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

1161

perror_plus("Failed to lower privileges after killing"

1162

" helper program");

1163

}

1164

return false;

1165

}

1166

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

1167

if(pret == -1){

1168

perror_plus("waitpid");

1169

return false;

1170

}

1171

if(WIFEXITED(status)){

1172

if(WEXITSTATUS(status) != 0){

1173

fprintf_plus(stderr, "Error: iprouteadddel exited"

1174

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

1175

return false;

1176

}

1177

return true;

1178

}

1179

if(WIFSIGNALED(status)){

1180

fprintf_plus(stderr, "Error: iprouteadddel died by"

1181

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

1182

return false;

1183

}

1184

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

1185

return false;

1186

}

1187

1188

__attribute__((nonnull, warn_unused_result))

1189

static bool add_local_route(const char *address,

1190

AvahiIfIndex if_index){

1191

if(debug){

1192

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

1193

}

1194

return add_delete_local_route(true, address, if_index);

1195

}

1196

1197

__attribute__((nonnull, warn_unused_result))

1198

static bool delete_local_route(const char *address,

1199

AvahiIfIndex if_index){

1200

if(debug){

1201

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

1202

}

1203

return add_delete_local_route(false, address, if_index);

1204

}

1205

1206

619

/* Called when a Mandos server is found */

1207

__attribute__((nonnull, warn_unused_result))

1208

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

620

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

1209

621

AvahiIfIndex if_index,

1210

int af, mandos_context *mc){

622

int af){

1211

623

int ret, tcp_sd = -1;

1212

624

ssize_t sret;

1213

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

1214

629

char *buffer = NULL;

1215

630

char *decrypted_buffer = NULL;

1216

631

size_t buffer_length = 0;

1219

634

int retval = -1;

1220

635

gnutls_session_t session;

1221

636

int pf; /* Protocol family */

1222

bool route_added = false;

1223

637

1224

638

errno = 0;

1225

639

1241

655

return -1;

1242

656

}

1243

657

1244

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

1245

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

1246

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

1247

bool match = false;

1248

{

1249

char *interface = NULL;

1250

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

1251

mc->interfaces_size,

1252

interface))){

1253

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

1254

match = true;

1255

break;

1256

}

1257

}

1258

}

1259

if(not match){

1260

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

1261

connect to the server */

1262

if(debug){

1263

char interface[IF_NAMESIZE];

1264

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

1265

perror_plus("if_indextoname");

1266

} else {

1267

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

1268

" \"%s\"\n",

1269

if_indextoname((unsigned int)if_index,

1270

interface));

1271

}

1272

}

1273

return -1;

1274

}

1275

}

1276

1277

ret = init_gnutls_session(&session, mc);

658

ret = init_gnutls_session(&session);

1278

659

if(ret != 0){

1279

660

return -1;

1280

661

}

1281

662

1282

663

if(debug){

1283

664

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

1284

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

665

PRIu16 "\n", ip, port);

1285

666

}

1286

667

1287

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

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

1288

669

if(tcp_sd < 0){

1289

670

int e = errno;

1290

671

perror_plus("socket");

1297

678

goto mandos_end;

1298

679

}

1299

680

681

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

1300

682

if(af == AF_INET6){

1301

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

1302

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

1303

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

683

to.in6.sin6_family = (sa_family_t)af;

684

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

1304

685

} else { /* IPv4 */

1305

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

1306

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

1307

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

686

to.in.sin_family = (sa_family_t)af;

687

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

1308

688

}

1309

689

if(ret < 0 ){

1310

690

int e = errno;

1319

699

goto mandos_end;

1320

700

}

1321

701

if(af == AF_INET6){

1322

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

1323

if(IN6_IS_ADDR_LINKLOCAL

1324

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

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

1325

709

if(if_index == AVAHI_IF_UNSPEC){

1326

710

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

1327

711

" incomplete without a network interface\n");

1329

713

goto mandos_end;

1330

714

}

1331

715

/* Set the network interface number as scope */

1332

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

1333

717

}

1334

718

} else {

1335

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

1336

722

}

1337

723

1338

724

if(quit_now){

1346

732

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

1347

733

perror_plus("if_indextoname");

1348

734

} else {

1349

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

1350

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

735

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

736

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

1351

737

}

1352

738

} else {

1353

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

1354

ip, (uintmax_t)port);

739

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

740

ip, port);

1355

741

}

1356

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1357

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1358

if(af == AF_INET6){

1359

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

1360

sizeof(struct sockaddr_in6),

1361

addrstr, sizeof(addrstr), NULL, 0,

1362

NI_NUMERICHOST);

1363

} else {

1364

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

1365

sizeof(struct sockaddr_in),

1366

addrstr, sizeof(addrstr), NULL, 0,

1367

NI_NUMERICHOST);

1368

}

1369

if(ret == EAI_SYSTEM){

1370

perror_plus("getnameinfo");

1371

} else if(ret != 0) {

1372

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

1373

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

1374

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

1375

}

1376

}

1377

1378

if(quit_now){

1379

errno = EINTR;

1380

goto mandos_end;

1381

}

1382

1383

while(true){

1384

if(af == AF_INET6){

1385

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

1386

sizeof(struct sockaddr_in6));

1387

} else {

1388

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

1389

sizeof(struct sockaddr_in));

1390

}

1391

if(ret < 0){

1392

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

1393

and if_index != AVAHI_IF_UNSPEC

1394

and connect_to == NULL

1395

and not route_added and

1396

((af == AF_INET6 and not

1397

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1398

&to)->sin6_addr)))

1399

or (af == AF_INET and

1400

/* Not a a IPv4LL address */

1401

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

1402

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

1403

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

1404

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

1405

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

1406

connect to a Mandos server announced by Avahi on a server

1407

host with a global address. Work around this by retrying

1408

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

1409

1410

Avahi bug reference:

1411

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

1412

https://bugs.debian.org/587961

1413

*/

1414

if(debug){

1415

fprintf_plus(stderr, "Mandos server unreachable, trying"

1416

" direct route\n");

1417

}

1418

int e = errno;

1419

route_added = add_local_route(ip, if_index);

1420

if(route_added){

1421

continue;

1422

}

1423

errno = e;

1424

}

1425

if(errno != ECONNREFUSED or debug){

1426

int e = errno;

1427

perror_plus("connect");

1428

errno = e;

1429

}

1430

goto mandos_end;

1431

}

1432

1433

if(quit_now){

1434

errno = EINTR;

1435

goto mandos_end;

1436

}

1437

break;

744

const char *pcret;

745

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

748

} else {

749

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

750

sizeof(addrstr));

751

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

758

}

759

}

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

if(af == AF_INET6){

767

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

768

} else {

769

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

770

}

771

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

1438

783

}

1439

784

1440

785

const char *out = mandos_protocol_version;

1476

821

goto mandos_end;

1477

822

}

1478

823

1479

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

1480

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

1481

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

1482

gnutls_transport_set_ptr(session,

1483

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1484

826

1485

827

if(quit_now){

1486

828

errno = EINTR;

1591

933

if(buffer_length > 0){

1592

934

ssize_t decrypted_buffer_size;

1593

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1594

&decrypted_buffer, mc);

936

&decrypted_buffer);

1595

937

if(decrypted_buffer_size >= 0){

1596

938

1597

clearerr(stdout);

1598

939

written = 0;

1599

940

while(written < (size_t) decrypted_buffer_size){

1600

941

if(quit_now){

1616

957

}

1617

958

written += (size_t)ret;

1618

959

}

1619

ret = fflush(stdout);

1620

if(ret != 0){

1621

int e = errno;

1622

if(debug){

1623

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

1624

strerror(errno));

1625

}

1626

errno = e;

1627

goto mandos_end;

1628

}

1629

960

retval = 0;

1630

961

}

1631

962

}

1634

965

1635

966

mandos_end:

1636

967

{

1637

if(route_added){

1638

if(not delete_local_route(ip, if_index)){

1639

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

1640

" interface %d", ip, if_index);

1641

}

1642

}

1643

968

int e = errno;

1644

969

free(decrypted_buffer);

1645

970

free(buffer);

1646

971

if(tcp_sd >= 0){

1647

ret = close(tcp_sd);

972

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

1648

973

}

1649

974

if(ret == -1){

1650

975

if(e == 0){

1675

1000

AVAHI_GCC_UNUSED AvahiStringList *txt,

1676

1001

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1677

1002

flags,

1678

void *mc){

1679

if(r == NULL){

1680

return;

1681

}

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1682

1005

1683

1006

/* Called whenever a service has been resolved successfully or

1684

1007

timed out */

1685

1008

1686

1009

if(quit_now){

1687

avahi_s_service_resolver_free(r);

1688

1010

return;

1689

1011

}

1690

1012

1694

1016

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

1695

1017

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

1696

1018

domain,

1697

avahi_strerror(avahi_server_errno

1698

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

1019

avahi_strerror(avahi_server_errno(mc.server)));

1699

1020

break;

1700

1021

1701

1022

case AVAHI_RESOLVER_FOUND:

1707

1028

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

1708

1029

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

1709

1030

}

1710

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

1711

interface,

1712

avahi_proto_to_af(proto),

1713

mc);

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1714

1033

if(ret == 0){

1715

avahi_simple_poll_quit(simple_poll);

1034

avahi_simple_poll_quit(mc.simple_poll);

1716

1035

} else {

1717

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

1718

avahi_proto_to_af(proto),

1719

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

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1720

1038

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

1721

1039

" list\n", name);

1722

1040

}

1735

1053

const char *domain,

1736

1054

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1737

1055

flags,

1738

void *mc){

1739

if(b == NULL){

1740

return;

1741

}

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1742

1058

1743

1059

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

1744

1060

is removed from the LAN */

1752

1068

case AVAHI_BROWSER_FAILURE:

1753

1069

1754

1070

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

1755

avahi_strerror(avahi_server_errno

1756

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

1757

avahi_simple_poll_quit(simple_poll);

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1758

1073

return;

1759

1074

1760

1075

case AVAHI_BROWSER_NEW:

1763

1078

the callback function is called the Avahi server will free the

1764

1079

resolver for us. */

1765

1080

1766

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

1767

interface, protocol, name, type,

1768

domain, protocol, 0,

1769

resolve_callback, mc) == NULL)

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1770

1084

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

1771

1085

" %s\n", name,

1772

avahi_strerror(avahi_server_errno

1773

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

1086

avahi_strerror(avahi_server_errno(mc.server)));

1774

1087

break;

1775

1088

1776

1089

case AVAHI_BROWSER_REMOVE:

1795

1108

signal_received = sig;

1796

1109

int old_errno = errno;

1797

1110

/* set main loop to exit */

1798

if(simple_poll != NULL){

1799

avahi_simple_poll_quit(simple_poll);

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1800

1113

}

1801

1114

errno = old_errno;

1802

1115

}

1803

1116

1804

__attribute__((nonnull, warn_unused_result))

1805

1117

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

1806

1118

int ret;

1807

int old_errno;

1808

1119

1809

1120

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

1810

1121

if(s < 0){

1811

old_errno = errno;

1812

1122

perror_plus("socket");

1813

errno = old_errno;

1814

1123

return false;

1815

1124

}

1816

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

1817

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

1125

strcpy(ifr->ifr_name, ifname);

1818

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1819

1127

if(ret == -1){

1820

1128

if(debug){

1821

old_errno = errno;

1822

1129

perror_plus("ioctl SIOCGIFFLAGS");

1823

errno = old_errno;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1829

1130

}

1830

1131

return false;

1831

1132

}

1832

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

1833

old_errno = errno;

1834

perror_plus("close");

1835

errno = old_errno;

1836

}

1837

1133

return true;

1838

1134

}

1839

1135

1840

__attribute__((nonnull, warn_unused_result))

1841

1136

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

1842

1137

1843

1138

/* Reject the loopback device */

1885

1180

* corresponds to an acceptable network device.

1886

1181

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

1887

1182

*/

1888

__attribute__((nonnull, warn_unused_result))

1889

1183

int good_interface(const struct dirent *if_entry){

1890

1184

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

1891

1185

return 0;

1907

1201

}

1908

1202

1909

1203

/*

1910

* This function determines if a network interface is up.

1911

*/

1912

__attribute__((nonnull, warn_unused_result))

1913

bool interface_is_up(const char *interface){

1914

struct ifreq ifr;

1915

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

1916

if(debug){

1917

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

1918

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

1919

}

1920

return false;

1921

}

1922

1923

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

1924

}

1925

1926

/*

1927

* This function determines if a network interface is running

1928

*/

1929

__attribute__((nonnull, warn_unused_result))

1930

bool interface_is_running(const char *interface){

1931

struct ifreq ifr;

1932

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

1933

if(debug){

1934

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

1935

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

1936

}

1937

return false;

1938

}

1939

1940

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

1941

}

1942

1943

__attribute__((nonnull, pure, warn_unused_result))

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1944

1246

int notdotentries(const struct dirent *direntry){

1945

1247

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

1946

1248

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

1953

1255

}

1954

1256

1955

1257

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

1956

__attribute__((nonnull, warn_unused_result))

1957

1258

int runnable_hook(const struct dirent *direntry){

1958

1259

int ret;

1959

1260

size_t sret;

1967

1268

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

1968

1269

"abcdefghijklmnopqrstuvwxyz"

1969

1270

"0123456789"

1970

"_.-");

1271

"_-");

1971

1272

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

1972

1273

/* Contains non-allowed characters */

1973

1274

if(debug){

1977

1278

return 0;

1978

1279

}

1979

1280

1980

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

1281

char *fullname = NULL;

1282

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

1283

if(ret < 0){

1284

perror_plus("asprintf");

1285

return 0;

1286

}

1287

1288

ret = stat(fullname, &st);

1981

1289

if(ret == -1){

1982

1290

if(debug){

1983

1291

perror_plus("Could not stat hook");

2007

1315

return 1;

2008

1316

}

2009

1317

2010

__attribute__((nonnull, warn_unused_result))

2011

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2012

mandos_context *mc){

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2013

1319

int ret;

2014

1320

struct timespec now;

2015

1321

struct timespec waited_time;

2016

1322

intmax_t block_time;

2017

1323

2018

1324

while(true){

2019

if(mc->current_server == NULL){

2020

if(debug){

1325

if(mc.current_server == NULL){

1326

if (debug){

2021

1327

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

2022

1328

" No timeout!\n");

2023

1329

}

2024

1330

ret = avahi_simple_poll_iterate(s, -1);

2025

1331

} else {

2026

if(debug){

1332

if (debug){

2027

1333

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

2028

1334

" it, or wait\n");

2029

1335

}

2036

1342

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

2037

1343

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

2038

1344

waited_time.tv_sec = (now.tv_sec

2039

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

1345

- mc.current_server->last_seen.tv_sec);

2040

1346

waited_time.tv_nsec = (now.tv_nsec

2041

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

1347

- mc.current_server->last_seen.tv_nsec);

2042

1348

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

2043

1349

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

2044

1350

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

2046

1352

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

2047

1353

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

2048

1354

2049

if(debug){

1355

if (debug){

2050

1356

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

2051

1357

block_time);

2052

1358

}

2053

1359

2054

1360

if(block_time <= 0){

2055

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

2056

mc->current_server->port,

2057

mc->current_server->if_index,

2058

mc->current_server->af, mc);

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

2059

1365

if(ret == 0){

2060

avahi_simple_poll_quit(s);

1366

avahi_simple_poll_quit(mc.simple_poll);

2061

1367

return 0;

2062

1368

}

2063

1369

ret = clock_gettime(CLOCK_MONOTONIC,

2064

&mc->current_server->last_seen);

1370

&mc.current_server->last_seen);

2065

1371

if(ret == -1){

2066

1372

perror_plus("clock_gettime");

2067

1373

return -1;

2068

1374

}

2069

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

1375

mc.current_server = mc.current_server->next;

2070

1376

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

2071

1377

servers, but don't block */

2072

1378

}

2074

1380

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

2075

1381

}

2076

1382

if(ret != 0){

2077

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

1383

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

2078

1384

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

2079

1385

}

2080

1386

}

2081

1387

}

2082

1388

}

2083

1389

2084

__attribute__((nonnull))

2085

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

1390

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

2086

1391

const float delay){

2087

struct dirent **direntries = NULL;

2088

if(hookdir_fd == -1){

2089

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2090

| O_CLOEXEC);

2091

if(hookdir_fd == -1){

2092

if(errno == ENOENT){

2093

if(debug){

2094

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

2095

" found\n", hookdir);

2096

}

2097

} else {

2098

perror_plus("open");

2099

}

2100

return;

2101

}

2102

}

2103

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

2104

if(devnull == -1){

2105

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

2106

return;

2107

}

2108

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

2109

runnable_hook, alphasort);

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

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

1396

alphasort);

2110

1397

if(numhooks == -1){

2111

1398

perror_plus("scandir");

2112

close(devnull);

2113

return;

2114

}

2115

struct dirent *direntry;

2116

int ret;

2117

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

2118

direntry = direntries[i];

2119

if(debug){

2120

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

2121

direntry->d_name);

2122

}

2123

pid_t hook_pid = fork();

2124

if(hook_pid == 0){

2125

/* Child */

2126

/* Raise privileges */

2127

errno = raise_privileges_permanently();

2128

if(errno != 0){

2129

perror_plus("Failed to raise privileges");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Set group */

2133

errno = 0;

2134

ret = setgid(0);

2135

if(ret == -1){

2136

perror_plus("setgid");

2137

_exit(EX_NOPERM);

2138

}

2139

/* Reset supplementary groups */

2140

errno = 0;

2141

ret = setgroups(0, NULL);

2142

if(ret == -1){

2143

perror_plus("setgroups");

2144

_exit(EX_NOPERM);

2145

}

2146

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

2147

if(ret == -1){

2148

perror_plus("setenv");

2149

_exit(EX_OSERR);

2150

}

2151

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

2152

if(ret == -1){

2153

perror_plus("setenv");

2154

_exit(EX_OSERR);

2155

}

2156

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

2157

if(ret == -1){

2158

perror_plus("setenv");

2159

_exit(EX_OSERR);

2160

}

2161

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

2162

if(ret == -1){

2163

perror_plus("setenv");

2164

_exit(EX_OSERR);

2165

}

2166

char *delaystring;

2167

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

2168

if(ret == -1){

1399

} else {

1400

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

1401

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

1402

direntry = direntries[i];

1403

char *fullname = NULL;

1404

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

1405

if(ret < 0){

2169

1406

perror_plus("asprintf");

2170

_exit(EX_OSERR);

2171

}

2172

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

2173

if(ret == -1){

1407

continue;

1408

}

1409

if(debug){

1410

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

1411

direntry->d_name);

1412

}

1413

pid_t hook_pid = fork();

1414

if(hook_pid == 0){

1415

/* Child */

1416

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1428

/* Set group */

1429

errno = 0;

1430

ret = setgid(0);

1431

if(ret == -1){

1432

perror_plus("setgid");

1433

}

1434

/* Reset supplementary groups */

1435

errno = 0;

1436

ret = setgroups(0, NULL);

1437

if(ret == -1){

1438

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1443

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

1444

if(ret == -1){

1445

perror_plus("setenv");

1446

_exit(EX_OSERR);

1447

}

1448

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

1449

if(ret == -1){

1450

perror_plus("setenv");

1451

_exit(EX_OSERR);

1452

}

1453

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

1454

if(ret == -1){

1455

perror_plus("setenv");

1456

_exit(EX_OSERR);

1457

}

1458

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

1459

if(ret == -1){

1460

perror_plus("setenv");

1461

_exit(EX_OSERR);

1462

}

1463

char *delaystring;

1464

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

1465

if(ret == -1){

1466

perror_plus("asprintf");

1467

_exit(EX_OSERR);

1468

}

1469

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

1470

if(ret == -1){

1471

free(delaystring);

1472

perror_plus("setenv");

1473

_exit(EX_OSERR);

1474

}

2174

1475

free(delaystring);

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

free(delaystring);

2179

if(connect_to != NULL){

2180

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

2181

if(ret == -1){

2182

perror_plus("setenv");

2183

_exit(EX_OSERR);

2184

}

2185

}

2186

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

2187

direntry->d_name,

2188

O_RDONLY));

2189

if(hook_fd == -1){

2190

perror_plus("openat");

2191

_exit(EXIT_FAILURE);

2192

}

2193

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

2194

perror_plus("close");

2195

_exit(EXIT_FAILURE);

2196

}

2197

ret = dup2(devnull, STDIN_FILENO);

2198

if(ret == -1){

2199

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

2200

_exit(EX_OSERR);

2201

}

2202

ret = close(devnull);

2203

if(ret == -1){

2204

perror_plus("close");

2205

_exit(EX_OSERR);

2206

}

2207

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2208

if(ret == -1){

2209

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

2210

_exit(EX_OSERR);

2211

}

2212

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

2213

environ) == -1){

2214

perror_plus("fexecve");

2215

_exit(EXIT_FAILURE);

2216

}

2217

} else {

2218

if(hook_pid == -1){

2219

perror_plus("fork");

2220

free(direntry);

2221

continue;

2222

}

2223

int status;

2224

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

2225

perror_plus("waitpid");

2226

free(direntry);

2227

continue;

2228

}

2229

if(WIFEXITED(status)){

2230

if(WEXITSTATUS(status) != 0){

2231

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

2232

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

2233

WEXITSTATUS(status));

2234

free(direntry);

2235

continue;

2236

}

2237

} else if(WIFSIGNALED(status)){

2238

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

2239

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

2240

WTERMSIG(status));

2241

free(direntry);

2242

continue;

2243

} else {

2244

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

2245

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

2246

free(direntry);

2247

continue;

2248

}

2249

}

2250

if(debug){

2251

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

2252

direntry->d_name);

2253

}

2254

free(direntry);

2255

}

2256

free(direntries);

2257

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

2258

perror_plus("close");

2259

} else {

2260

hookdir_fd = -1;

2261

}

2262

close(devnull);

2263

}

2264

2265

__attribute__((nonnull, warn_unused_result))

2266

int bring_up_interface(const char *const interface,

2267

const float delay){

2268

int old_errno = errno;

2269

int ret;

2270

struct ifreq network;

2271

unsigned int if_index = if_nametoindex(interface);

2272

if(if_index == 0){

2273

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

2274

errno = old_errno;

2275

return ENXIO;

2276

}

2277

2278

if(quit_now){

2279

errno = old_errno;

2280

return EINTR;

2281

}

2282

2283

if(not interface_is_up(interface)){

2284

int ret_errno = 0;

2285

int ioctl_errno = 0;

2286

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

2287

ret_errno = errno;

2288

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

2289

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

2290

errno = old_errno;

2291

return ret_errno;

2292

}

2293

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

2294

2295

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

2296

if(sd == -1){

2297

ret_errno = errno;

2298

perror_plus("socket");

2299

errno = old_errno;

2300

return ret_errno;

2301

}

2302

2303

if(quit_now){

2304

ret = close(sd);

2305

if(ret == -1){

2306

perror_plus("close");

2307

}

2308

errno = old_errno;

2309

return EINTR;

2310

}

2311

2312

if(debug){

2313

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

2314

interface);

2315

}

2316

2317

/* Raise privileges */

2318

ret_errno = raise_privileges();

2319

if(ret_errno != 0){

2320

errno = ret_errno;

2321

perror_plus("Failed to raise privileges");

2322

}

2323

2324

#ifdef __linux__

2325

int ret_linux;

2326

bool restore_loglevel = false;

2327

if(ret_errno == 0){

2328

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2329

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

2330

ret_linux = klogctl(8, NULL, 5);

2331

if(ret_linux == -1){

2332

perror_plus("klogctl");

2333

} else {

2334

restore_loglevel = true;

2335

}

2336

}

2337

#endif /* __linux__ */

2338

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

2339

ioctl_errno = errno;

2340

#ifdef __linux__

2341

if(restore_loglevel){

2342

ret_linux = klogctl(7, NULL, 0);

2343

if(ret_linux == -1){

2344

perror_plus("klogctl");

2345

}

2346

}

2347

#endif /* __linux__ */

2348

2349

/* If raise_privileges() succeeded above */

2350

if(ret_errno == 0){

2351

/* Lower privileges */

2352

ret_errno = lower_privileges();

2353

if(ret_errno != 0){

2354

errno = ret_errno;

2355

perror_plus("Failed to lower privileges");

2356

}

2357

}

2358

2359

/* Close the socket */

2360

ret = close(sd);

2361

if(ret == -1){

2362

perror_plus("close");

2363

}

2364

2365

if(ret_setflags == -1){

2366

errno = ioctl_errno;

2367

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2368

errno = old_errno;

2369

return ioctl_errno;

2370

}

2371

} else if(debug){

2372

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

2373

interface);

2374

}

2375

2376

/* Sleep checking until interface is running.

2377

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

2378

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

2379

if(interface_is_running(interface)){

2380

break;

2381

}

2382

struct timespec sleeptime = { .tv_nsec = 250000000 };

2383

ret = nanosleep(&sleeptime, NULL);

2384

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

2385

perror_plus("nanosleep");

2386

}

2387

}

2388

2389

errno = old_errno;

2390

return 0;

2391

}

2392

2393

__attribute__((nonnull, warn_unused_result))

2394

int take_down_interface(const char *const interface){

2395

int old_errno = errno;

2396

struct ifreq network;

2397

unsigned int if_index = if_nametoindex(interface);

2398

if(if_index == 0){

2399

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

2400

errno = old_errno;

2401

return ENXIO;

2402

}

2403

if(interface_is_up(interface)){

2404

int ret_errno = 0;

2405

int ioctl_errno = 0;

2406

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

2407

ret_errno = errno;

2408

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

2409

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

2410

errno = old_errno;

2411

return ret_errno;

2412

}

2413

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

2414

2415

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

2416

if(sd == -1){

2417

ret_errno = errno;

2418

perror_plus("socket");

2419

errno = old_errno;

2420

return ret_errno;

2421

}

2422

2423

if(debug){

2424

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

2425

interface);

2426

}

2427

2428

/* Raise privileges */

2429

ret_errno = raise_privileges();

2430

if(ret_errno != 0){

2431

errno = ret_errno;

2432

perror_plus("Failed to raise privileges");

2433

}

2434

2435

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

2436

ioctl_errno = errno;

2437

2438

/* If raise_privileges() succeeded above */

2439

if(ret_errno == 0){

2440

/* Lower privileges */

2441

ret_errno = lower_privileges();

2442

if(ret_errno != 0){

2443

errno = ret_errno;

2444

perror_plus("Failed to lower privileges");

2445

}

2446

}

2447

2448

/* Close the socket */

2449

int ret = close(sd);

2450

if(ret == -1){

2451

perror_plus("close");

2452

}

2453

2454

if(ret_setflags == -1){

2455

errno = ioctl_errno;

2456

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2457

errno = old_errno;

2458

return ioctl_errno;

2459

}

2460

} else if(debug){

2461

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

2462

interface);

2463

}

2464

2465

errno = old_errno;

2466

return 0;

1476

if(connect_to != NULL){

1477

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

1478

if(ret == -1){

1479

perror_plus("setenv");

1480

_exit(EX_OSERR);

1481

}

1482

}

1483

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

1484

perror_plus("execl");

1485

_exit(EXIT_FAILURE);

1486

}

1487

} else {

1488

int status;

1489

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

1490

perror_plus("waitpid");

1491

free(fullname);

1492

continue;

1493

}

1494

if(WIFEXITED(status)){

1495

if(WEXITSTATUS(status) != 0){

1496

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

1497

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

1498

WEXITSTATUS(status));

1499

free(fullname);

1500

continue;

1501

}

1502

} else if(WIFSIGNALED(status)){

1503

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

1504

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

1505

WTERMSIG(status));

1506

free(fullname);

1507

continue;

1508

} else {

1509

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

1510

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

1511

free(fullname);

1512

continue;

1513

}

1514

}

1515

free(fullname);

1516

if(debug){

1517

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

1518

direntry->d_name);

1519

}

1520

}

1521

close(devnull);

1522

}

1523

return true;

2467

1524

}

2468

1525

2469

1526

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

2470

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

2471

#if GNUTLS_VERSION_NUMBER >= 0x030606

2472

.priority = "SECURE128:!CTYPE-X.509"

2473

":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"

2474

":%PROFILE_ULTRA",

2475

#elif GNUTLS_VERSION_NUMBER < 0x030600

2476

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

2477

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

2478

#else

2479

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

2480

#endif

2481

.current_server = NULL, .interfaces = NULL,

2482

.interfaces_size = 0 };

2483

1527

AvahiSServiceBrowser *sb = NULL;

2484

error_t ret_errno;

1528

int error;

2485

1529

int ret;

2486

1530

intmax_t tmpmax;

2487

1531

char *tmp;

2488

1532

int exitcode = EXIT_SUCCESS;

2489

char *interfaces_to_take_down = NULL;

2490

size_t interfaces_to_take_down_size = 0;

2491

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

2492

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

2493

char *tempdir = NULL;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1539

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

1540

bool tempdir_created = false;

2494

1541

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2495

1542

const char *seckey = PATHDIR "/" SECKEY;

2496

1543

const char *pubkey = PATHDIR "/" PUBKEY;

2497

#if GNUTLS_VERSION_NUMBER >= 0x030606

2498

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2499

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2500

#endif

2501

const char *dh_params_file = NULL;

2502

char *interfaces_hooks = NULL;

2503

1544

2504

1545

bool gnutls_initialized = false;

2505

1546

bool gpgme_initialized = false;

2551

1592

{ .name = "pubkey", .key = 'p',

2552

1593

.arg = "FILE",

2553

1594

.doc = "OpenPGP public key file base name",

2554

.group = 1 },

2555

{ .name = "tls-privkey", .key = 't',

2556

.arg = "FILE",

2557

#if GNUTLS_VERSION_NUMBER >= 0x030606

2558

.doc = "TLS private key file base name",

2559

#else

2560

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2561

#endif

2562

.group = 1 },

2563

{ .name = "tls-pubkey", .key = 'T',

2564

.arg = "FILE",

2565

#if GNUTLS_VERSION_NUMBER >= 0x030606

2566

.doc = "TLS public key file base name",

2567

#else

2568

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2569

#endif

2570

.group = 1 },

1595

.group = 2 },

2571

1596

{ .name = "dh-bits", .key = 129,

2572

1597

.arg = "BITS",

2573

1598

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

2574

1599

" Diffie-Hellman key exchange",

2575

1600

.group = 2 },

2576

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

2577

.arg = "FILE",

2578

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

2579

" for the Diffie-Hellman key exchange",

2580

.group = 2 },

2581

1601

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

2582

1602

.arg = "STRING",

2583

1603

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

2617

1637

connect_to = arg;

2618

1638

break;

2619

1639

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

2620

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

2621

arg, (int)',');

2622

if(ret_errno != 0){

2623

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

2624

}

1640

interface = arg;

2625

1641

break;

2626

1642

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

2627

1643

seckey = arg;

2629

1645

case 'p': /* --pubkey */

2630

1646

pubkey = arg;

2631

1647

break;

2632

case 't': /* --tls-privkey */

2633

#if GNUTLS_VERSION_NUMBER >= 0x030606

2634

tls_privkey = arg;

2635

#endif

2636

break;

2637

case 'T': /* --tls-pubkey */

2638

#if GNUTLS_VERSION_NUMBER >= 0x030606

2639

tls_pubkey = arg;

2640

#endif

2641

break;

2642

1648

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

2643

1649

errno = 0;

2644

1650

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

2648

1654

}

2649

1655

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

2650

1656

break;

2651

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

2652

dh_params_file = arg;

2653

break;

2654

1657

case 130: /* --priority */

2655

1658

mc.priority = arg;

2656

1659

break;

2679

1682

argp_state_help(state, state->out_stream,

2680

1683

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2681

1684

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2682

__builtin_unreachable();

2683

1685

case -3: /* --usage */

2684

1686

argp_state_help(state, state->out_stream,

2685

1687

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2686

__builtin_unreachable();

2687

1688

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

2688

1689

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

2689

1690

exit(argp_err_exit_status);

2698

1699

.args_doc = "",

2699

1700

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

2700

1701

" passwords from a Mandos server" };

2701

ret_errno = argp_parse(&argp, argc, argv,

2702

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2703

switch(ret_errno){

1702

ret = argp_parse(&argp, argc, argv,

1703

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1704

switch(ret){

2704

1705

case 0:

2705

1706

break;

2706

1707

case ENOMEM:

2707

1708

default:

2708

errno = ret_errno;

1709

errno = ret;

2709

1710

perror_plus("argp_parse");

2710

1711

exitcode = EX_OSERR;

2711

1712

goto end;

2714

1715

goto end;

2715

1716

}

2716

1717

}

2717

1718

2718

1719

{

2719

1720

/* Work around Debian bug #633582:

2720

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

1721

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

2721

1722

2722

/* Re-raise privileges */

2723

ret = raise_privileges();

2724

if(ret != 0){

2725

errno = ret;

2726

perror_plus("Failed to raise privileges");

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

2727

1728

} else {

2728

1729

struct stat st;

2729

1730

2744

1745

}

2745

1746

}

2746

1747

}

2747

close(seckey_fd);

1748

TEMP_FAILURE_RETRY(close(seckey_fd));

2748

1749

}

2749

1750

}

2750

1751

2751

1752

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

2752

1753

int pubkey_fd = open(pubkey, O_RDONLY);

2753

1754

if(pubkey_fd == -1){

2765

1766

}

2766

1767

}

2767

1768

}

2768

close(pubkey_fd);

2769

}

2770

}

2771

2772

if(dh_params_file != NULL

2773

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

2774

int dhparams_fd = open(dh_params_file, O_RDONLY);

2775

if(dhparams_fd == -1){

2776

perror_plus("open");

2777

} else {

2778

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

2779

if(ret == -1){

2780

perror_plus("fstat");

2781

} else {

2782

if(S_ISREG(st.st_mode)

2783

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

2784

ret = fchown(dhparams_fd, uid, gid);

2785

if(ret == -1){

2786

perror_plus("fchown");

2787

}

2788

}

2789

}

2790

close(dhparams_fd);

2791

}

2792

}

2793

1769

TEMP_FAILURE_RETRY(close(pubkey_fd));

1770

}

1771

}

1772

2794

1773

/* Lower privileges */

2795

ret = lower_privileges();

2796

if(ret != 0){

2797

errno = ret;

2798

perror_plus("Failed to lower privileges");

2799

}

2800

}

2801

}

2802

2803

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

2804

{

2805

char *interface = NULL;

2806

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

2807

interface))){

2808

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

2809

and if_nametoindex(interface) == 0){

2810

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

2811

fprintf_plus(stderr, "Not using nonexisting interface"

2812

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

2813

}

2814

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

2815

interface = NULL;

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

2816

1778

}

2817

1779

}

2818

1780

}

2819

1781

2820

1782

/* Run network hooks */

2821

{

2822

if(mc.interfaces != NULL){

2823

interfaces_hooks = malloc(mc.interfaces_size);

2824

if(interfaces_hooks == NULL){

2825

perror_plus("malloc");

2826

goto end;

2827

}

2828

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

2829

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

2830

}

2831

run_network_hooks("start", interfaces_hooks != NULL ?

2832

interfaces_hooks : "", delay);

1783

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

1784

goto end;

2833

1785

}

2834

1786

2835

1787

if(not debug){

2836

1788

avahi_set_log_function(empty_log);

2837

1789

}

2838

1790

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

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

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

2839

1823

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

2840

1824

from the signal handler */

2841

1825

/* Initialize the pseudo-RNG for Avahi */

2842

1826

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

2843

simple_poll = avahi_simple_poll_new();

2844

if(simple_poll == NULL){

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2845

1829

fprintf_plus(stderr,

2846

1830

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

2847

1831

exitcode = EX_UNAVAILABLE;

2911

1895

}

2912

1896

}

2913

1897

2914

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

2915

if(mc.interfaces == NULL){

2916

struct dirent **direntries = NULL;

2917

/* Look for any good interfaces */

2918

ret = scandir(sys_class_net, &direntries, good_interface,

2919

alphasort);

2920

if(ret >= 1){

2921

/* Add all found interfaces to interfaces list */

2922

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

2923

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

2924

direntries[i]->d_name);

2925

if(ret_errno != 0){

2926

errno = ret_errno;

2927

perror_plus("argz_add");

2928

free(direntries[i]);

2929

continue;

2930

}

2931

if(debug){

2932

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

2933

direntries[i]->d_name);

2934

}

2935

free(direntries[i]);

2936

}

2937

free(direntries);

2938

} else {

2939

if(ret == 0){

2940

free(direntries);

2941

}

2942

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

2943

exitcode = EXIT_FAILURE;

2944

goto end;

2945

}

2946

}

2947

2948

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

2949

{

2950

char *interface = NULL;

2951

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

2952

interface))){

2953

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

2954

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

2955

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

2956

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

2957

interface);

2958

interface = NULL;

2959

while((interface = argz_next(mc.interfaces,

2960

mc.interfaces_size, interface))){

2961

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

2962

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

2963

interface);

2964

interface = NULL;

1898

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

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

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

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

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

2965

1983

}

2966

1984

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

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

1997

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

1998

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

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2967

2002

break;

2968

2003

}

2969

bool interface_was_up = interface_is_up(interface);

2970

errno = bring_up_interface(interface, delay);

2971

if(not interface_was_up){

2972

if(errno != 0){

2973

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

2974

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

2975

} else {

2976

errno = argz_add(&interfaces_to_take_down,

2977

&interfaces_to_take_down_size,

2978

interface);

2979

if(errno != 0){

2980

perror_plus("argz_add");

2981

}

2982

}

2983

}

2984

}

2985

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

2986

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

2987

}

2988

}

2989

2990

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

2991

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

2992

if(debug){

2993

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

2994

mc.interfaces);

2995

}

2996

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

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2997

2033

}

2998

2034

2999

2035

if(quit_now){

3000

2036

goto end;

3001

2037

}

3002

2038

3003

#if GNUTLS_VERSION_NUMBER >= 0x030606

3004

ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);

3005

#elif GNUTLS_VERSION_NUMBER < 0x030600

3006

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

3007

#else

3008

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

3009

#endif

2039

ret = init_gnutls_global(pubkey, seckey);

3010

2040

if(ret == -1){

3011

2041

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

3012

2042

exitcode = EX_UNAVAILABLE;

3019

2049

goto end;

3020

2050

}

3021

2051

3022

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

3023

tempdir = mkdtemp(run_tempdir);

3024

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

3025

if(debug){

3026

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

3027

run_tempdir, old_tempdir);

3028

}

3029

tempdir = mkdtemp(old_tempdir);

3030

}

3031

if(tempdir == NULL){

2052

if(mkdtemp(tempdir) == NULL){

3032

2053

perror_plus("mkdtemp");

3033

2054

goto end;

3034

2055

}

2056

tempdir_created = true;

3035

2057

3036

2058

if(quit_now){

3037

2059

goto end;

3038

2060

}

3039

2061

3040

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

2062

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

3041

2063

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

3042

2064

exitcode = EX_UNAVAILABLE;

3043

2065

goto end;

3053

2075

/* Connect directly, do not use Zeroconf */

3054

2076

/* (Mainly meant for debugging) */

3055

2077

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

3056

3057

2078

if(address == NULL){

3058

2079

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

3059

2080

exitcode = EX_USAGE;

3064

2085

goto end;

3065

2086

}

3066

2087

3067

in_port_t port;

2088

uint16_t port;

3068

2089

errno = 0;

3069

2090

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

3070

2091

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

3071

or tmpmax != (in_port_t)tmpmax){

2092

or tmpmax != (uint16_t)tmpmax){

3072

2093

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

3073

2094

exitcode = EX_USAGE;

3074

2095

goto end;

3075

2096

}

3076

2097

3077

2098

if(quit_now){

3078

2099

goto end;

3079

2100

}

3080

2101

3081

port = (in_port_t)tmpmax;

2102

port = (uint16_t)tmpmax;

3082

2103

*address = '\0';

3083

2104

/* Colon in address indicates IPv6 */

3084

2105

int af;

3100

2121

}

3101

2122

3102

2123

while(not quit_now){

3103

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

3104

&mc);

2124

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

3105

2125

if(quit_now or ret == 0){

3106

2126

break;

3107

2127

}

3109

2129

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

3110

2130

(int)retry_interval);

3111

2131

}

3112

sleep((unsigned int)retry_interval);

2132

sleep((int)retry_interval);

3113

2133

}

3114

2134

3115

if(not quit_now){

2135

if (not quit_now){

3116

2136

exitcode = EXIT_SUCCESS;

3117

2137

}

3118

2138

3133

2153

config.publish_domain = 0;

3134

2154

3135

2155

/* Allocate a new server */

3136

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3137

&config, NULL, NULL, &ret);

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

3138

2159

3139

2160

/* Free the Avahi configuration data */

3140

2161

avahi_server_config_free(&config);

3143

2164

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

3144

2165

if(mc.server == NULL){

3145

2166

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

3146

avahi_strerror(ret));

2167

avahi_strerror(error));

3147

2168

exitcode = EX_UNAVAILABLE;

3148

2169

goto end;

3149

2170

}

3155

2176

/* Create the Avahi service browser */

3156

2177

sb = avahi_s_service_browser_new(mc.server, if_index,

3157

2178

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3158

NULL, 0, browse_callback,

3159

(void *)&mc);

2179

NULL, 0, browse_callback, NULL);

3160

2180

if(sb == NULL){

3161

2181

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

3162

2182

avahi_strerror(avahi_server_errno(mc.server)));

3173

2193

if(debug){

3174

2194

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

3175

2195

}

3176

3177

ret = avahi_loop_with_timeout(simple_poll,

3178

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

2196

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

3179

2199

if(debug){

3180

2200

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

3181

2201

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

3184

2204

end:

3185

2205

3186

2206

if(debug){

3187

if(signal_received){

3188

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

3189

argv[0], signal_received,

3190

strsignal(signal_received));

3191

} else {

3192

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

3193

}

2207

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

3194

2208

}

3195

2209

3196

2210

/* Cleanup things */

3197

free(mc.interfaces);

3198

3199

2211

if(sb != NULL)

3200

2212

avahi_s_service_browser_free(sb);

3201

2213

3202

2214

if(mc.server != NULL)

3203

2215

avahi_server_free(mc.server);

3204

2216

3205

if(simple_poll != NULL)

3206

avahi_simple_poll_free(simple_poll);

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

3207

2219

3208

2220

if(gnutls_initialized){

3209

2221

gnutls_certificate_free_credentials(mc.cred);

2222

gnutls_global_deinit();

3210

2223

gnutls_dh_params_deinit(mc.dh_params);

3211

2224

}

3212

2225

3220

2233

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

3221

2234

while(mc.current_server != NULL){

3222

2235

server *next = mc.current_server->next;

3223

#ifdef __GNUC__

3224

#pragma GCC diagnostic push

3225

#pragma GCC diagnostic ignored "-Wcast-qual"

3226

#endif

3227

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

3228

#ifdef __GNUC__

3229

#pragma GCC diagnostic pop

3230

#endif

3231

2236

free(mc.current_server);

3232

2237

mc.current_server = next;

3233

2238

}

3234

2239

}

3235

2240

3236

/* Re-raise privileges */

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

3237

2245

{

3238

ret = raise_privileges();

3239

if(ret != 0){

3240

errno = ret;

3241

perror_plus("Failed to raise privileges");

3242

} else {

3243

3244

/* Run network hooks */

3245

run_network_hooks("stop", interfaces_hooks != NULL ?

3246

interfaces_hooks : "", delay);

3247

3248

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

3249

{

3250

char *interface = NULL;

3251

while((interface = argz_next(interfaces_to_take_down,

3252

interfaces_to_take_down_size,

3253

interface))){

3254

ret = take_down_interface(interface);

3255

if(ret != 0){

3256

errno = ret;

3257

perror_plus("Failed to take down interface");

3258

}

3259

}

3260

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

3261

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

3262

" down\n");

3263

}

3264

}

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

3265

2250

}

3266

2251

3267

ret = lower_privileges_permanently();

3268

if(ret != 0){

3269

errno = ret;

3270

perror_plus("Failed to lower privileges permanently");

2252

/* Take down the network interface */

2253

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

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

3271

2268

}

3272

2269

}

3273

3274

free(interfaces_to_take_down);

3275

free(interfaces_hooks);

3276

3277

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

3278

uintmax_t level){

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2276

2277

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

2278

if(tempdir_created){

3279

2279

struct dirent **direntries = NULL;

3280

int dret;

3281

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

3282

O_RDONLY

3283

| O_NOFOLLOW

3284

| O_DIRECTORY

3285

| O_PATH));

3286

if(dir_fd == -1){

3287

perror_plus("open");

3288

return;

3289

}

3290

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

3291

notdotentries, alphasort);

3292

if(numentries >= 0){

2280

struct dirent *direntry = NULL;

2281

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

2282

alphasort);

2283

if (numentries > 0){

3293

2284

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

3294

if(debug){

3295

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

3296

dirname, direntries[i]->d_name);

3297

}

3298

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

3299

if(dret == -1){

3300

if(errno == EISDIR){

3301

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

3302

AT_REMOVEDIR);

3303

}

3304

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

3305

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

3306

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

3307

/* Recurse only in this special case */

3308

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

3309

dret = 0;

3310

}

3311

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

3312

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

3313

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

3314

}

3315

}

3316

free(direntries[i]);

3317

}

3318

3319

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

3320

free(direntries);

3321

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3322

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

3323

perror_plus("rmdir");

3324

}

3325

} else {

3326

perror_plus("scandirat");

3327

}

3328

close(dir_fd);

3329

}

3330

3331

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

3332

if(tempdir != NULL){

3333

clean_dir_at(-1, tempdir, 0);

2285

direntry = direntries[i];

2286

char *fullname = NULL;

2287

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

2288

direntry->d_name);

2289

if(ret < 0){

2290

perror_plus("asprintf");

2291

continue;

2292

}

2293

ret = remove(fullname);

2294

if(ret == -1){

2295

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

2296

strerror(errno));

2297

}

2298

free(fullname);

2299

}

2300

}

2301

2302

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

2303

free(direntries);

2304

if (numentries == -1){

2305

perror_plus("scandir");

2306

}

2307

ret = rmdir(tempdir);

2308

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

2309

perror_plus("rmdir");

2310

}

3334

2311

}

3335

2312

3336

2313

if(quit_now){