/mandos/release : revision 237.7.703

9

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

10

*

11

* Everything else is

12

13

14

*

15

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

16

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

17

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

18

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

19

*

20

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

12

13

14

*

15

* This file is part of Mandos.

16

*

17

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

18

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

19

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

20

* (at your option) any later version.

21

*

22

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

21

23

* WITHOUT ANY WARRANTY; without even the implied warranty of

22

24

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

23

25

* General Public License for more details.

24

26

*

25

27

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

26

* along with this program. If not, see

27

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

28

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

28

29

*

29

* Contact the authors at <mandos@fukt.bsnet.se>.

30

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

30

31

*/

31

32

33

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

33

34

#ifndef _LARGEFILE_SOURCE

34

35

#define _LARGEFILE_SOURCE

35

#endif

36

#endif /* not _LARGEFILE_SOURCE */

36

37

#ifndef _FILE_OFFSET_BITS

37

38

#define _FILE_OFFSET_BITS 64

38

#endif

39

#endif /* not _FILE_OFFSET_BITS */

39

40

41

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

41

42

43

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

43

stdout, ferror(), remove() */

44

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

44

stdout, ferror() */

45

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

45

46

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

46

47

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

47

48

strtof(), abort() */

48

49

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

49

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

50

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

50

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

51

asprintf(), strncpy(), strsignal()

52

*/

51

53

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

52

54

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

53

55

sockaddr_in6, PF_INET6,

54

56

SOCK_STREAM, uid_t, gid_t, open(),

55

57

opendir(), DIR */

56

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

58

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

57

59

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

58

inet_pton(), connect() */

59

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

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

60

63

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

61

64

*/

62

65

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

63

66

strtoimax() */

64

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

65

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

67

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

68

EAI_SYSTEM, ENETUNREACH,

69

EHOSTUNREACH, ECONNREFUSED, EPROTO,

70

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

71

ENOTEMPTY,

72

program_invocation_short_name */

66

73

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

67

74

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

68

75

SIOCSIFFLAGS, if_indextoname(),

72

79

*/

73

80

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

74

81

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

75

setgid(), pause() */

76

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

82

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

83

unlinkat() */

84

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

77

85

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

78

86

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

79

87

argp_state, struct argp,

84

92

raise() */

85

93

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

86

94

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

95

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

96

WEXITSTATUS(), WTERMSIG() */

97

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

98

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

99

argz_delete(), argz_append(),

100

argz_stringify(), argz_add(),

101

argz_count() */

102

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

103

EAI_SYSTEM, gai_strerror() */

87

104

88

105

#ifdef __linux__

89

106

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

106

123

gnutls_*

107

124

init_gnutls_session(),

108

125

GNUTLS_* */

126

#if GNUTLS_VERSION_NUMBER < 0x030600

109

127

#include <gnutls/openpgp.h>

110

/* gnutls_certificate_set_openpgp_key_file(),

111

GNUTLS_OPENPGP_FMT_BASE64 */

128

/* gnutls_certificate_set_openpgp_key_file(),

129

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

112

135

113

136

/* GPGME */

114

137

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

122

145

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

123

146

#define SECKEY "seckey.txt"

124

147

#define PUBKEY "pubkey.txt"

148

#define TLS_PRIVKEY "tls-privkey.pem"

149

#define TLS_PUBKEY "tls-pubkey.pem"

150

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

125

151

126

152

bool debug = false;

127

153

static const char mandos_protocol_version[] = "1";

128

154

const char *argp_program_version = "mandos-client " VERSION;

129

const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

155

const char *argp_program_bug_address = "<mandos@recompile.se>";

130

156

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

131

157

char *connect_to = NULL;

158

const char *hookdir = HOOKDIR;

159

int hookdir_fd = -1;

160

uid_t uid = 65534;

161

gid_t gid = 65534;

132

162

133

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

163

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

134

164

typedef struct server{

135

165

const char *ip;

136

uint16_t port;

166

in_port_t port;

137

167

AvahiIfIndex if_index;

138

168

int af;

139

169

struct timespec last_seen;

143

173

144

174

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

145

175

typedef struct {

146

AvahiSimplePoll *simple_poll;

147

176

AvahiServer *server;

148

177

gnutls_certificate_credentials_t cred;

149

178

unsigned int dh_bits;

151

180

const char *priority;

152

181

gpgme_ctx_t ctx;

153

182

server *current_server;

183

char *interfaces;

184

size_t interfaces_size;

154

185

} mandos_context;

155

186

156

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

157

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

158

.dh_bits = 1024, .priority = "SECURE256"

159

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

187

/* global so signal handler can reach it*/

188

AvahiSimplePoll *simple_poll;

160

189

161

190

sig_atomic_t quit_now = 0;

162

191

int signal_received = 0;

163

192

164

193

/* Function to use when printing errors */

165

194

void perror_plus(const char *print_text){

166

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

195

int e = errno;

196

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

197

program_invocation_short_name);

198

errno = e;

167

199

perror(print_text);

168

200

}

169

201

202

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

203

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

204

va_list ap;

205

va_start (ap, format);

206

207

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

208

program_invocation_short_name));

209

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

210

}

211

170

212

/*

171

213

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

172

214

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

173

215

* "buffer_length" is how much is already used.

174

216

*/

217

__attribute__((nonnull, warn_unused_result))

175

218

size_t incbuffer(char **buffer, size_t buffer_length,

176

size_t buffer_capacity){

219

size_t buffer_capacity){

177

220

if(buffer_length + BUFFER_SIZE > buffer_capacity){

178

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

179

if(buffer == NULL){

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;

180

227

return 0;

181

228

}

229

*buffer = new_buf;

182

230

buffer_capacity += BUFFER_SIZE;

183

231

}

184

232

return buffer_capacity;

185

233

}

186

234

187

int add_server(const char *ip, uint16_t port,

188

AvahiIfIndex if_index,

189

int af){

235

/* 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){

190

239

int ret;

191

240

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

192

241

if(new_server == NULL){

193

242

perror_plus("malloc");

194

return -1;

243

return false;

195

244

}

196

245

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

197

.port = port,

198

.if_index = if_index,

199

.af = af };

246

.port = port,

247

.if_index = if_index,

248

.af = af };

200

249

if(new_server->ip == NULL){

201

250

perror_plus("strdup");

202

return -1;

203

}

204

/* uniqe case of first server */

205

if (mc.current_server == NULL){

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

return false;

267

}

268

/* Special case of first server */

269

if(*current_server == NULL){

206

270

new_server->next = new_server;

207

271

new_server->prev = new_server;

208

mc.current_server = new_server;

209

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

272

*current_server = new_server;

210

273

} else {

211

new_server->next = mc.current_server;

212

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

274

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

275

new_server->next = *current_server;

276

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

213

277

new_server->prev->next = new_server;

214

mc.current_server->prev = new_server;

215

}

216

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

217

if(ret == -1){

218

perror_plus("clock_gettime");

219

return -1;

220

}

221

return 0;

278

(*current_server)->prev = new_server;

279

}

280

return true;

281

}

282

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;

222

333

}

223

334

224

335

/*

225

336

* Initialize GPGME.

226

337

*/

227

static bool init_gpgme(const char *seckey,

228

const char *pubkey, const char *tempdir){

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){

229

343

gpgme_error_t rc;

230

344

gpgme_engine_info_t engine_info;

231

345

232

233

346

/*

234

347

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

235

348

*/

236

bool import_key(const char *filename){

349

bool import_key(const char * const filename){

237

350

int ret;

238

351

int fd;

239

352

gpgme_data_t pgp_data;

244

357

return false;

245

358

}

246

359

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

247

410

rc = gpgme_data_new_from_fd(&pgp_data, fd);

248

411

if(rc != GPG_ERR_NO_ERROR){

249

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

250

gpgme_strsource(rc), gpgme_strerror(rc));

412

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

413

gpgme_strsource(rc), gpgme_strerror(rc));

251

414

return false;

252

415

}

253

416

254

rc = gpgme_op_import(mc.ctx, pgp_data);

417

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

255

418

if(rc != GPG_ERR_NO_ERROR){

256

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

257

gpgme_strsource(rc), gpgme_strerror(rc));

419

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

420

gpgme_strsource(rc), gpgme_strerror(rc));

258

421

return false;

259

422

}

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

}

260

498

261

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

499

ret = close(fd);

262

500

if(ret == -1){

263

501

perror_plus("close");

264

502

}

267

505

}

268

506

269

507

if(debug){

270

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

508

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

271

509

}

272

510

273

511

/* Init GPGME */

274

512

gpgme_check_version(NULL);

275

513

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

276

514

if(rc != GPG_ERR_NO_ERROR){

277

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

278

gpgme_strsource(rc), gpgme_strerror(rc));

515

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

516

gpgme_strsource(rc), gpgme_strerror(rc));

279

517

return false;

280

518

}

281

519

282

/* Set GPGME home directory for the OpenPGP engine only */

520

/* Set GPGME home directory for the OpenPGP engine only */

283

521

rc = gpgme_get_engine_info(&engine_info);

284

522

if(rc != GPG_ERR_NO_ERROR){

285

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

286

gpgme_strsource(rc), gpgme_strerror(rc));

523

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

524

gpgme_strsource(rc), gpgme_strerror(rc));

287

525

return false;

288

526

}

289

527

while(engine_info != NULL){

295

533

engine_info = engine_info->next;

296

534

}

297

535

if(engine_info == NULL){

298

fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);

536

fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",

537

tempdir);

299

538

return false;

300

539

}

301

540

302

541

/* Create new GPGME "context" */

303

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

542

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

304

543

if(rc != GPG_ERR_NO_ERROR){

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

307

546

return false;

308

547

}

309

548

318

557

* Decrypt OpenPGP data.

319

558

* Returns -1 on error

320

559

*/

560

__attribute__((nonnull, warn_unused_result))

321

561

static ssize_t pgp_packet_decrypt(const char *cryptotext,

322

562

size_t crypto_size,

323

char **plaintext){

563

char **plaintext,

564

mandos_context *mc){

324

565

gpgme_data_t dh_crypto, dh_plain;

325

566

gpgme_error_t rc;

326

567

ssize_t ret;

328

569

ssize_t plaintext_length = 0;

329

570

330

571

if(debug){

331

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

572

fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");

332

573

}

333

574

334

575

/* Create new GPGME data buffer from memory cryptotext */

335

576

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

336

577

0);

337

578

if(rc != GPG_ERR_NO_ERROR){

338

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

339

gpgme_strsource(rc), gpgme_strerror(rc));

579

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

580

gpgme_strsource(rc), gpgme_strerror(rc));

340

581

return -1;

341

582

}

342

583

343

584

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

344

585

rc = gpgme_data_new(&dh_plain);

345

586

if(rc != GPG_ERR_NO_ERROR){

346

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

347

gpgme_strsource(rc), gpgme_strerror(rc));

587

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

588

gpgme_strsource(rc), gpgme_strerror(rc));

348

589

gpgme_data_release(dh_crypto);

349

590

return -1;

350

591

}

351

592

352

593

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

353

594

data buffer */

354

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

595

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

355

596

if(rc != GPG_ERR_NO_ERROR){

356

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

357

gpgme_strsource(rc), gpgme_strerror(rc));

597

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

598

gpgme_strsource(rc), gpgme_strerror(rc));

358

599

plaintext_length = -1;

359

600

if(debug){

360

601

gpgme_decrypt_result_t result;

361

result = gpgme_op_decrypt_result(mc.ctx);

602

result = gpgme_op_decrypt_result(mc->ctx);

362

603

if(result == NULL){

363

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

604

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

364

605

} else {

365

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

366

result->unsupported_algorithm);

367

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

368

result->wrong_key_usage);

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");

369

612

if(result->file_name != NULL){

370

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

613

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

371

614

}

372

gpgme_recipient_t recipient;

373

recipient = result->recipients;

374

while(recipient != NULL){

375

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

376

gpgme_pubkey_algo_name(recipient->pubkey_algo));

377

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

378

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

379

recipient->status == GPG_ERR_NO_SECKEY

380

? "No" : "Yes");

381

recipient = recipient->next;

615

616

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

617

r = r->next){

618

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);

621

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

622

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

382

623

}

383

624

}

384

625

}

386

627

}

387

628

388

629

if(debug){

389

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

630

fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");

390

631

}

391

632

392

633

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

399

640

*plaintext = NULL;

400

641

while(true){

401

642

plaintext_capacity = incbuffer(plaintext,

402

(size_t)plaintext_length,

403

plaintext_capacity);

643

(size_t)plaintext_length,

644

plaintext_capacity);

404

645

if(plaintext_capacity == 0){

405

perror_plus("incbuffer");

406

plaintext_length = -1;

407

goto decrypt_end;

646

perror_plus("incbuffer");

647

plaintext_length = -1;

648

goto decrypt_end;

408

649

}

409

650

410

651

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

423

664

}

424

665

425

666

if(debug){

426

fprintf(stderr, "Decrypted password is: ");

667

fprintf_plus(stderr, "Decrypted password is: ");

427

668

for(ssize_t i = 0; i < plaintext_length; i++){

428

669

fprintf(stderr, "%02hhX ", (*plaintext)[i]);

429

670

}

440

681

return plaintext_length;

441

682

}

442

683

443

static const char * safer_gnutls_strerror(int value){

444

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

445

-Wunreachable-code */

446

if(ret == NULL)

447

ret = "(unknown)";

448

return ret;

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);

449

695

}

450

696

451

697

/* GnuTLS log function callback */

698

__attribute__((nonnull))

452

699

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

453

700

const char* string){

454

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

701

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

455

702

}

456

703

704

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

457

705

static int init_gnutls_global(const char *pubkeyfilename,

458

const char *seckeyfilename){

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

mandos_context *mc){

459

709

int ret;

460

710

461

711

if(debug){

462

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

463

}

464

465

ret = gnutls_global_init();

466

if(ret != GNUTLS_E_SUCCESS){

467

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

468

safer_gnutls_strerror(ret));

469

return -1;

712

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

470

713

}

471

714

472

715

if(debug){

478

721

}

479

722

480

723

/* OpenPGP credentials */

481

gnutls_certificate_allocate_credentials(&mc.cred);

724

ret = gnutls_certificate_allocate_credentials(&mc->cred);

482

725

if(ret != GNUTLS_E_SUCCESS){

483

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

484

from

485

-Wunreachable-code

486

*/

487

safer_gnutls_strerror(ret));

488

gnutls_global_deinit();

726

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

727

safer_gnutls_strerror(ret));

489

728

return -1;

490

729

}

491

730

492

731

if(debug){

493

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

494

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

495

seckeyfilename);

732

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

733

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

734

pubkeyfilename,

735

seckeyfilename);

496

736

}

497

737

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

498

751

ret = gnutls_certificate_set_openpgp_key_file

499

(mc.cred, pubkeyfilename, seckeyfilename,

752

(mc->cred, pubkeyfilename, seckeyfilename,

500

753

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

501

757

if(ret != GNUTLS_E_SUCCESS){

502

fprintf(stderr,

503

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

504

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

505

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

506

safer_gnutls_strerror(ret));

758

fprintf_plus(stderr,

759

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

760

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

761

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

762

safer_gnutls_strerror(ret));

507

763

goto globalfail;

508

764

}

509

765

510

766

/* GnuTLS server initialization */

511

ret = gnutls_dh_params_init(&mc.dh_params);

512

if(ret != GNUTLS_E_SUCCESS){

513

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

514

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

515

goto globalfail;

516

}

517

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

518

if(ret != GNUTLS_E_SUCCESS){

519

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

520

safer_gnutls_strerror(ret));

521

goto globalfail;

522

}

523

524

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

767

ret = gnutls_dh_params_init(&mc->dh_params);

768

if(ret != GNUTLS_E_SUCCESS){

769

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

770

" initialization: %s\n",

771

safer_gnutls_strerror(ret));

772

goto globalfail;

773

}

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

}

525

956

526

957

return 0;

527

958

528

959

globalfail:

529

960

530

gnutls_certificate_free_credentials(mc.cred);

531

gnutls_global_deinit();

532

gnutls_dh_params_deinit(mc.dh_params);

961

gnutls_certificate_free_credentials(mc->cred);

962

gnutls_dh_params_deinit(mc->dh_params);

533

963

return -1;

534

964

}

535

965

536

static int init_gnutls_session(gnutls_session_t *session){

966

__attribute__((nonnull, warn_unused_result))

967

static int init_gnutls_session(gnutls_session_t *session,

968

mandos_context *mc){

537

969

int ret;

538

970

/* GnuTLS session creation */

539

971

do {

540

ret = gnutls_init(session, GNUTLS_SERVER);

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

));

541

980

if(quit_now){

542

981

return -1;

543

982

}

544

983

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

545

984

if(ret != GNUTLS_E_SUCCESS){

546

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

547

safer_gnutls_strerror(ret));

985

fprintf_plus(stderr,

986

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

987

safer_gnutls_strerror(ret));

548

988

}

549

989

550

990

{

551

991

const char *err;

552

992

do {

553

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

993

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

554

994

if(quit_now){

555

995

gnutls_deinit(*session);

556

996

return -1;

557

997

}

558

998

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

559

999

if(ret != GNUTLS_E_SUCCESS){

560

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

561

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

562

safer_gnutls_strerror(ret));

1000

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

1001

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

1002

safer_gnutls_strerror(ret));

563

1003

gnutls_deinit(*session);

564

1004

return -1;

565

1005

}

567

1007

568

1008

do {

569

1009

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

570

mc.cred);

1010

mc->cred);

571

1011

if(quit_now){

572

1012

gnutls_deinit(*session);

573

1013

return -1;

574

1014

}

575

1015

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

576

1016

if(ret != GNUTLS_E_SUCCESS){

577

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

578

safer_gnutls_strerror(ret));

1017

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

1018

safer_gnutls_strerror(ret));

579

1019

gnutls_deinit(*session);

580

1020

return -1;

581

1021

}

583

1023

/* ignore client certificate if any. */

584

1024

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

585

1025

586

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

587

588

1026

return 0;

589

1027

}

590

1028

592

1030

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

593

1031

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

594

1032

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

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

_exit(EX_NOPERM);

1085

}

1086

}

1087

ret = dup2(devnull, STDIN_FILENO);

1088

if(ret == -1){

1089

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

1090

_exit(EX_OSERR);

1091

}

1092

ret = close(devnull);

1093

if(ret == -1){

1094

perror_plus("close");

1095

_exit(EX_OSERR);

1096

}

1097

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1098

if(ret == -1){

1099

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

1100

_exit(EX_OSERR);

1101

}

1102

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

1103

O_RDONLY

1104

| O_DIRECTORY

1105

| O_PATH

1106

| O_CLOEXEC));

1107

if(helperdir_fd == -1){

1108

perror_plus("open");

1109

_exit(EX_UNAVAILABLE);

1110

}

1111

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

1112

helper, O_RDONLY));

1113

if(helper_fd == -1){

1114

perror_plus("openat");

1115

close(helperdir_fd);

1116

_exit(EX_UNAVAILABLE);

1117

}

1118

close(helperdir_fd);

1119

#ifdef __GNUC__

1120

#pragma GCC diagnostic push

1121

#pragma GCC diagnostic ignored "-Wcast-qual"

1122

#endif

1123

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

1124

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

1125

interface, debug ? debug_flag : NULL, NULL },

1126

environ) == -1){

1127

#ifdef __GNUC__

1128

#pragma GCC diagnostic pop

1129

#endif

1130

perror_plus("fexecve");

1131

_exit(EXIT_FAILURE);

1132

}

1133

}

1134

if(pid == -1){

1135

perror_plus("fork");

1136

return false;

1137

}

1138

int status;

1139

pid_t pret = -1;

1140

errno = 0;

1141

do {

1142

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

1143

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

1144

int errno_raising = 0;

1145

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

1146

errno_raising = errno;

1147

perror_plus("Failed to raise privileges in order to"

1148

" kill helper program");

1149

}

1150

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

1151

perror_plus("kill");

1152

}

1153

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

1154

perror_plus("Failed to lower privileges after killing"

1155

" helper program");

1156

}

1157

return false;

1158

}

1159

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

1160

if(pret == -1){

1161

perror_plus("waitpid");

1162

return false;

1163

}

1164

if(WIFEXITED(status)){

1165

if(WEXITSTATUS(status) != 0){

1166

fprintf_plus(stderr, "Error: iprouteadddel exited"

1167

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

1168

return false;

1169

}

1170

return true;

1171

}

1172

if(WIFSIGNALED(status)){

1173

fprintf_plus(stderr, "Error: iprouteadddel died by"

1174

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

1175

return false;

1176

}

1177

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

1178

return false;

1179

}

1180

1181

__attribute__((nonnull, warn_unused_result))

1182

static bool add_local_route(const char *address,

1183

AvahiIfIndex if_index){

1184

if(debug){

1185

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

1186

}

1187

return add_delete_local_route(true, address, if_index);

1188

}

1189

1190

__attribute__((nonnull, warn_unused_result))

1191

static bool delete_local_route(const char *address,

1192

AvahiIfIndex if_index){

1193

if(debug){

1194

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

1195

}

1196

return add_delete_local_route(false, address, if_index);

1197

}

1198

595

1199

/* Called when a Mandos server is found */

596

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

1200

__attribute__((nonnull, warn_unused_result))

1201

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

597

1202

AvahiIfIndex if_index,

598

int af){

1203

int af, mandos_context *mc){

599

1204

int ret, tcp_sd = -1;

600

1205

ssize_t sret;

601

union {

602

struct sockaddr_in in;

603

struct sockaddr_in6 in6;

604

} to;

1206

struct sockaddr_storage to;

605

1207

char *buffer = NULL;

606

1208

char *decrypted_buffer = NULL;

607

1209

size_t buffer_length = 0;

610

1212

int retval = -1;

611

1213

gnutls_session_t session;

612

1214

int pf; /* Protocol family */

1215

bool route_added = false;

613

1216

614

1217

errno = 0;

615

1218

626

1229

pf = PF_INET;

627

1230

break;

628

1231

default:

629

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

1232

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

630

1233

errno = EINVAL;

631

1234

return -1;

632

1235

}

633

1236

634

ret = init_gnutls_session(&session);

1237

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

1238

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

1239

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

1240

bool match = false;

1241

{

1242

char *interface = NULL;

1243

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

1244

mc->interfaces_size,

1245

interface))){

1246

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

1247

match = true;

1248

break;

1249

}

1250

}

1251

}

1252

if(not match){

1253

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

1254

connect to the server */

1255

if(debug){

1256

char interface[IF_NAMESIZE];

1257

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

1258

perror_plus("if_indextoname");

1259

} else {

1260

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

1261

" \"%s\"\n",

1262

if_indextoname((unsigned int)if_index,

1263

interface));

1264

}

1265

}

1266

return -1;

1267

}

1268

}

1269

1270

ret = init_gnutls_session(&session, mc);

635

1271

if(ret != 0){

636

1272

return -1;

637

1273

}

638

1274

639

1275

if(debug){

640

fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16

641

"\n", ip, port);

1276

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

1277

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

642

1278

}

643

1279

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

1280

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

645

1281

if(tcp_sd < 0){

646

1282

int e = errno;

647

1283

perror_plus("socket");

654

1290

goto mandos_end;

655

1291

}

656

1292

657

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

658

1293

if(af == AF_INET6){

659

to.in6.sin6_family = (sa_family_t)af;

660

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

1294

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

1295

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

1296

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

661

1297

} else { /* IPv4 */

662

to.in.sin_family = (sa_family_t)af;

663

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

1298

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

1299

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

1300

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

664

1301

}

665

1302

if(ret < 0 ){

666

1303

int e = errno;

670

1307

}

671

1308

if(ret == 0){

672

1309

int e = errno;

673

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

1310

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

674

1311

errno = e;

675

1312

goto mandos_end;

676

1313

}

677

1314

if(af == AF_INET6){

678

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

679

-Wconversion and

680

-Wunreachable-code */

681

682

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

683

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

684

-Wunreachable-code*/

1315

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

1316

if(IN6_IS_ADDR_LINKLOCAL

1317

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

685

1318

if(if_index == AVAHI_IF_UNSPEC){

686

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

687

" without a network interface\n");

1319

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

1320

" incomplete without a network interface\n");

688

1321

errno = EINVAL;

689

1322

goto mandos_end;

690

1323

}

691

1324

/* Set the network interface number as scope */

692

to.in6.sin6_scope_id = (uint32_t)if_index;

1325

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

693

1326

}

694

1327

} else {

695

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

696

-Wconversion and

697

-Wunreachable-code */

1328

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

698

1329

}

699

1330

700

1331

if(quit_now){

708

1339

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

709

1340

perror_plus("if_indextoname");

710

1341

} else {

711

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

712

ip, interface, port);

1342

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

1343

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

713

1344

}

714

1345

} else {

715

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

716

port);

1346

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

1347

ip, (uintmax_t)port);

717

1348

}

718

1349

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

719

1350

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

720

const char *pcret;

721

if(af == AF_INET6){

722

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

723

sizeof(addrstr));

724

} else {

725

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

726

sizeof(addrstr));

727

}

728

if(pcret == NULL){

729

perror_plus("inet_ntop");

730

} else {

731

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

732

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

733

}

734

}

735

}

736

737

if(quit_now){

738

errno = EINTR;

739

goto mandos_end;

740

}

741

742

if(af == AF_INET6){

743

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

744

} else {

745

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

746

}

747

if(ret < 0){

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

753

goto mandos_end;

754

}

755

756

if(quit_now){

757

errno = EINTR;

758

goto mandos_end;

1351

if(af == AF_INET6){

1352

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

1353

sizeof(struct sockaddr_in6),

1354

addrstr, sizeof(addrstr), NULL, 0,

1355

NI_NUMERICHOST);

1356

} else {

1357

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

1358

sizeof(struct sockaddr_in),

1359

addrstr, sizeof(addrstr), NULL, 0,

1360

NI_NUMERICHOST);

1361

}

1362

if(ret == EAI_SYSTEM){

1363

perror_plus("getnameinfo");

1364

} else if(ret != 0) {

1365

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

1366

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

1367

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

1368

}

1369

}

1370

1371

if(quit_now){

1372

errno = EINTR;

1373

goto mandos_end;

1374

}

1375

1376

while(true){

1377

if(af == AF_INET6){

1378

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

1379

sizeof(struct sockaddr_in6));

1380

} else {

1381

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

1382

sizeof(struct sockaddr_in));

1383

}

1384

if(ret < 0){

1385

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

1386

and if_index != AVAHI_IF_UNSPEC

1387

and connect_to == NULL

1388

and not route_added and

1389

((af == AF_INET6 and not

1390

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1391

&to)->sin6_addr)))

1392

or (af == AF_INET and

1393

/* Not a a IPv4LL address */

1394

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

1395

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

1396

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

1397

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

1398

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

1399

connect to a Mandos server announced by Avahi on a server

1400

host with a global address. Work around this by retrying

1401

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

1402

1403

Avahi bug reference:

1404

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

1405

https://bugs.debian.org/587961

1406

*/

1407

if(debug){

1408

fprintf_plus(stderr, "Mandos server unreachable, trying"

1409

" direct route\n");

1410

}

1411

int e = errno;

1412

route_added = add_local_route(ip, if_index);

1413

if(route_added){

1414

continue;

1415

}

1416

errno = e;

1417

}

1418

if(errno != ECONNREFUSED or debug){

1419

int e = errno;

1420

perror_plus("connect");

1421

errno = e;

1422

}

1423

goto mandos_end;

1424

}

1425

1426

if(quit_now){

1427

errno = EINTR;

1428

goto mandos_end;

1429

}

1430

break;

759

1431

}

760

1432

761

1433

const char *out = mandos_protocol_version;

763

1435

while(true){

764

1436

size_t out_size = strlen(out);

765

1437

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

766

out_size - written));

1438

out_size - written));

767

1439

if(ret == -1){

768

1440

int e = errno;

769

1441

perror_plus("write");

789

1461

}

790

1462

791

1463

if(debug){

792

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

1464

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

793

1465

}

794

1466

795

1467

if(quit_now){

796

1468

errno = EINTR;

797

1469

goto mandos_end;

798

1470

}

799

800

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

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1471

1472

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

1473

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

1474

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

1475

gnutls_transport_set_ptr(session,

1476

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

802

1477

803

1478

if(quit_now){

804

1479

errno = EINTR;

815

1490

816

1491

if(ret != GNUTLS_E_SUCCESS){

817

1492

if(debug){

818

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

1493

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

819

1494

gnutls_perror(ret);

820

1495

}

821

1496

errno = EPROTO;

825

1500

/* Read OpenPGP packet that contains the wanted password */

826

1501

827

1502

if(debug){

828

fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",

829

ip);

1503

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1504

" %s\n", ip);

830

1505

}

831

1506

832

1507

while(true){

837

1512

}

838

1513

839

1514

buffer_capacity = incbuffer(&buffer, buffer_length,

840

buffer_capacity);

1515

buffer_capacity);

841

1516

if(buffer_capacity == 0){

842

1517

int e = errno;

843

1518

perror_plus("incbuffer");

870

1545

}

871

1546

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

872

1547

if(ret < 0){

873

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

1548

fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "

1549

"***\n");

874

1550

gnutls_perror(ret);

875

1551

errno = EPROTO;

876

1552

goto mandos_end;

877

1553

}

878

1554

break;

879

1555

default:

880

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

881

" encrypted session with Mandos server\n");

1556

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

1557

" encrypted session with Mandos server\n");

882

1558

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

1559

errno = EIO;

884

1560

goto mandos_end;

889

1565

}

890

1566

891

1567

if(debug){

892

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

1568

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

893

1569

}

894

1570

895

1571

if(quit_now){

907

1583

908

1584

if(buffer_length > 0){

909

1585

ssize_t decrypted_buffer_size;

910

decrypted_buffer_size = pgp_packet_decrypt(buffer,

911

buffer_length,

912

&decrypted_buffer);

1586

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1587

&decrypted_buffer, mc);

913

1588

if(decrypted_buffer_size >= 0){

914

1589

1590

clearerr(stdout);

915

1591

written = 0;

916

1592

while(written < (size_t) decrypted_buffer_size){

917

1593

if(quit_now){

925

1601

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

926

1602

int e = errno;

927

1603

if(debug){

928

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

929

strerror(errno));

1604

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

1605

strerror(errno));

930

1606

}

931

1607

errno = e;

932

1608

goto mandos_end;

933

1609

}

934

1610

written += (size_t)ret;

935

1611

}

1612

ret = fflush(stdout);

1613

if(ret != 0){

1614

int e = errno;

1615

if(debug){

1616

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

1617

strerror(errno));

1618

}

1619

errno = e;

1620

goto mandos_end;

1621

}

936

1622

retval = 0;

937

1623

}

938

1624

}

941

1627

942

1628

mandos_end:

943

1629

{

1630

if(route_added){

1631

if(not delete_local_route(ip, if_index)){

1632

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

1633

" interface %d", ip, if_index);

1634

}

1635

}

944

1636

int e = errno;

945

1637

free(decrypted_buffer);

946

1638

free(buffer);

947

1639

if(tcp_sd >= 0){

948

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

1640

ret = close(tcp_sd);

949

1641

}

950

1642

if(ret == -1){

951

1643

if(e == 0){

976

1668

AVAHI_GCC_UNUSED AvahiStringList *txt,

977

1669

AVAHI_GCC_UNUSED AvahiLookupResultFlags

978

1670

flags,

979

AVAHI_GCC_UNUSED void* userdata){

980

assert(r);

1671

void *mc){

1672

if(r == NULL){

1673

return;

1674

}

981

1675

982

1676

/* Called whenever a service has been resolved successfully or

983

1677

timed out */

984

1678

985

1679

if(quit_now){

1680

avahi_s_service_resolver_free(r);

986

1681

return;

987

1682

}

988

1683

989

1684

switch(event){

990

1685

default:

991

1686

case AVAHI_RESOLVER_FAILURE:

992

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

993

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

994

avahi_strerror(avahi_server_errno(mc.server)));

1687

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

1688

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

1689

domain,

1690

avahi_strerror(avahi_server_errno

1691

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

995

1692

break;

996

1693

997

1694

case AVAHI_RESOLVER_FOUND:

999

1696

char ip[AVAHI_ADDRESS_STR_MAX];

1000

1697

avahi_address_snprint(ip, sizeof(ip), address);

1001

1698

if(debug){

1002

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"

1003

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

1004

ip, (intmax_t)interface, port);

1699

fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"

1700

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

1701

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

1005

1702

}

1006

int ret = start_mandos_communication(ip, port, interface,

1007

avahi_proto_to_af(proto));

1703

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

1704

interface,

1705

avahi_proto_to_af(proto),

1706

mc);

1008

1707

if(ret == 0){

1009

avahi_simple_poll_quit(mc.simple_poll);

1708

avahi_simple_poll_quit(simple_poll);

1010

1709

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

1710

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

1711

avahi_proto_to_af(proto),

1712

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

1713

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

1714

" list\n", name);

1715

}

1013

1716

}

1014

1717

}

1015

1718

}

1025

1728

const char *domain,

1026

1729

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1027

1730

flags,

1028

AVAHI_GCC_UNUSED void* userdata){

1029

assert(b);

1731

void *mc){

1732

if(b == NULL){

1733

return;

1734

}

1030

1735

1031

1736

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

1032

1737

is removed from the LAN */

1039

1744

default:

1040

1745

case AVAHI_BROWSER_FAILURE:

1041

1746

1042

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

1043

avahi_strerror(avahi_server_errno(mc.server)));

1044

avahi_simple_poll_quit(mc.simple_poll);

1747

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

1748

avahi_strerror(avahi_server_errno

1749

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

1750

avahi_simple_poll_quit(simple_poll);

1045

1751

return;

1046

1752

1047

1753

case AVAHI_BROWSER_NEW:

1050

1756

the callback function is called the Avahi server will free the

1051

1757

resolver for us. */

1052

1758

1053

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

1054

name, type, domain, protocol, 0,

1055

resolve_callback, NULL) == NULL)

1056

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

1057

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

1759

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

1760

interface, protocol, name, type,

1761

domain, protocol, 0,

1762

resolve_callback, mc) == NULL)

1763

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

1764

" %s\n", name,

1765

avahi_strerror(avahi_server_errno

1766

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

1058

1767

break;

1059

1768

1060

1769

case AVAHI_BROWSER_REMOVE:

1063

1772

case AVAHI_BROWSER_ALL_FOR_NOW:

1064

1773

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1065

1774

if(debug){

1066

fprintf(stderr, "No Mandos server found, still searching...\n");

1775

fprintf_plus(stderr, "No Mandos server found, still"

1776

" searching...\n");

1067

1777

}

1068

1778

break;

1069

1779

}

1070

1780

}

1071

1781

1072

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

1782

/* Signal handler that stops main loop after SIGTERM */

1073

1783

static void handle_sigterm(int sig){

1074

1784

if(quit_now){

1075

1785

return;

1078

1788

signal_received = sig;

1079

1789

int old_errno = errno;

1080

1790

/* set main loop to exit */

1081

if(mc.simple_poll != NULL){

1082

avahi_simple_poll_quit(mc.simple_poll);

1791

if(simple_poll != NULL){

1792

avahi_simple_poll_quit(simple_poll);

1083

1793

}

1084

1794

errno = old_errno;

1085

1795

}

1086

1796

1797

__attribute__((nonnull, warn_unused_result))

1798

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

1799

int ret;

1800

int old_errno;

1801

1802

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

1803

if(s < 0){

1804

old_errno = errno;

1805

perror_plus("socket");

1806

errno = old_errno;

1807

return false;

1808

}

1809

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

1810

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

1811

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1812

if(ret == -1){

1813

if(debug){

1814

old_errno = errno;

1815

perror_plus("ioctl SIOCGIFFLAGS");

1816

errno = old_errno;

1817

}

1818

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

1819

old_errno = errno;

1820

perror_plus("close");

1821

errno = old_errno;

1822

}

1823

return false;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1829

}

1830

return true;

1831

}

1832

1833

__attribute__((nonnull, warn_unused_result))

1834

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

1835

1836

/* Reject the loopback device */

1837

if(ifr->ifr_flags & IFF_LOOPBACK){

1838

if(debug){

1839

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

1840

ifname);

1841

}

1842

return false;

1843

}

1844

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

1845

if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){

1846

if(debug){

1847

fprintf_plus(stderr, "Accepting point-to-point interface"

1848

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

1849

}

1850

return true;

1851

}

1852

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

1853

if(not (ifr->ifr_flags & IFF_BROADCAST)){

1854

if(debug){

1855

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1856

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

1857

}

1858

return false;

1859

}

1860

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

1861

if(ifr->ifr_flags & IFF_NOARP){

1862

if(debug){

1863

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

1864

ifname);

1865

}

1866

return false;

1867

}

1868

1869

/* Accept this device */

1870

if(debug){

1871

fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);

1872

}

1873

return true;

1874

}

1875

1087

1876

/*

1088

1877

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

1089

1878

* corresponds to an acceptable network device.

1090

1879

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

1091

1880

*/

1881

__attribute__((nonnull, warn_unused_result))

1092

1882

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

1883

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

1096

1884

return 0;

1097

1885

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1886

1887

struct ifreq ifr;

1888

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

1889

if(debug){

1890

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

1891

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

1892

}

1893

return 0;

1894

}

1895

1896

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

1897

return 0;

1188

1898

}

1189

1899

return 1;

1190

1900

}

1191

1901

1902

/*

1903

* This function determines if a network interface is up.

1904

*/

1905

__attribute__((nonnull, warn_unused_result))

1906

bool interface_is_up(const char *interface){

1907

struct ifreq ifr;

1908

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

1909

if(debug){

1910

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

1911

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

1912

}

1913

return false;

1914

}

1915

1916

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

1917

}

1918

1919

/*

1920

* This function determines if a network interface is running

1921

*/

1922

__attribute__((nonnull, warn_unused_result))

1923

bool interface_is_running(const char *interface){

1924

struct ifreq ifr;

1925

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

1926

if(debug){

1927

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

1928

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

1929

}

1930

return false;

1931

}

1932

1933

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

1934

}

1935

1936

__attribute__((nonnull, pure, warn_unused_result))

1192

1937

int notdotentries(const struct dirent *direntry){

1193

1938

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

1194

1939

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

1200

1945

return 1;

1201

1946

}

1202

1947

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1948

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

1949

__attribute__((nonnull, warn_unused_result))

1950

int runnable_hook(const struct dirent *direntry){

1951

int ret;

1952

size_t sret;

1953

struct stat st;

1954

1955

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

1956

/* Empty name? */

1957

return 0;

1958

}

1959

1960

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

1961

"abcdefghijklmnopqrstuvwxyz"

1962

"0123456789"

1963

"_.-");

1964

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

1965

/* Contains non-allowed characters */

1966

if(debug){

1967

fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",

1968

direntry->d_name);

1969

}

1970

return 0;

1971

}

1972

1973

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

1974

if(ret == -1){

1975

if(debug){

1976

perror_plus("Could not stat hook");

1977

}

1978

return 0;

1979

}

1980

if(not (S_ISREG(st.st_mode))){

1981

/* Not a regular file */

1982

if(debug){

1983

fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",

1984

direntry->d_name);

1985

}

1986

return 0;

1987

}

1988

if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){

1989

/* Not executable */

1990

if(debug){

1991

fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",

1992

direntry->d_name);

1993

}

1994

return 0;

1995

}

1996

if(debug){

1997

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

1998

direntry->d_name);

1999

}

2000

return 1;

2001

}

2002

2003

__attribute__((nonnull, warn_unused_result))

2004

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2005

mandos_context *mc){

1204

2006

int ret;

1205

2007

struct timespec now;

1206

2008

struct timespec waited_time;

1207

2009

intmax_t block_time;

1208

2010

1209

2011

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

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

2012

if(mc->current_server == NULL){

2013

if(debug){

2014

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

2015

" No timeout!\n");

1213

2016

}

1214

2017

ret = avahi_simple_poll_iterate(s, -1);

1215

2018

} else {

1216

if (debug){

1217

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

2019

if(debug){

2020

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

2021

" it, or wait\n");

1218

2022

}

1219

2023

/* the current time */

1220

2024

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1224

2028

}

1225

2029

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

1226

2030

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

1227

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

1228

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

1229

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

1230

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

1231

1232

if (debug){

1233

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

2031

waited_time.tv_sec = (now.tv_sec

2032

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

2033

waited_time.tv_nsec = (now.tv_nsec

2034

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

2035

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

2036

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

2037

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

2038

block_time = ((retry_interval

2039

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

2040

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

2041

2042

if(debug){

2043

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

2044

block_time);

1234

2045

}

1235

2046

1236

2047

if(block_time <= 0){

1237

ret = start_mandos_communication(mc.current_server->ip,

1238

mc.current_server->port,

1239

mc.current_server->if_index,

1240

mc.current_server->af);

2048

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

2049

mc->current_server->port,

2050

mc->current_server->if_index,

2051

mc->current_server->af, mc);

1241

2052

if(ret == 0){

1242

avahi_simple_poll_quit(mc.simple_poll);

2053

avahi_simple_poll_quit(s);

1243

2054

return 0;

1244

2055

}

1245

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

2056

ret = clock_gettime(CLOCK_MONOTONIC,

2057

&mc->current_server->last_seen);

1246

2058

if(ret == -1){

1247

2059

perror_plus("clock_gettime");

1248

2060

return -1;

1249

2061

}

1250

mc.current_server = mc.current_server->next;

1251

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

2062

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

2063

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

2064

servers, but don't block */

1252

2065

}

1253

2066

1254

2067

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

1255

2068

}

1256

2069

if(ret != 0){

1257

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

2070

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

1258

2071

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

1259

2072

}

1260

2073

}

1261

2074

}

1262

2075

}

1263

2076

2077

__attribute__((nonnull))

2078

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

2079

const float delay){

2080

struct dirent **direntries = NULL;

2081

if(hookdir_fd == -1){

2082

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2083

| O_CLOEXEC);

2084

if(hookdir_fd == -1){

2085

if(errno == ENOENT){

2086

if(debug){

2087

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

2088

" found\n", hookdir);

2089

}

2090

} else {

2091

perror_plus("open");

2092

}

2093

return;

2094

}

2095

}

2096

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

2097

if(devnull == -1){

2098

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

2099

return;

2100

}

2101

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

2102

runnable_hook, alphasort);

2103

if(numhooks == -1){

2104

perror_plus("scandir");

2105

close(devnull);

2106

return;

2107

}

2108

struct dirent *direntry;

2109

int ret;

2110

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

2111

direntry = direntries[i];

2112

if(debug){

2113

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

2114

direntry->d_name);

2115

}

2116

pid_t hook_pid = fork();

2117

if(hook_pid == 0){

2118

/* Child */

2119

/* Raise privileges */

2120

errno = raise_privileges_permanently();

2121

if(errno != 0){

2122

perror_plus("Failed to raise privileges");

2123

_exit(EX_NOPERM);

2124

}

2125

/* Set group */

2126

errno = 0;

2127

ret = setgid(0);

2128

if(ret == -1){

2129

perror_plus("setgid");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Reset supplementary groups */

2133

errno = 0;

2134

ret = setgroups(0, NULL);

2135

if(ret == -1){

2136

perror_plus("setgroups");

2137

_exit(EX_NOPERM);

2138

}

2139

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

2140

if(ret == -1){

2141

perror_plus("setenv");

2142

_exit(EX_OSERR);

2143

}

2144

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

2145

if(ret == -1){

2146

perror_plus("setenv");

2147

_exit(EX_OSERR);

2148

}

2149

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

2150

if(ret == -1){

2151

perror_plus("setenv");

2152

_exit(EX_OSERR);

2153

}

2154

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

2155

if(ret == -1){

2156

perror_plus("setenv");

2157

_exit(EX_OSERR);

2158

}

2159

char *delaystring;

2160

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

2161

if(ret == -1){

2162

perror_plus("asprintf");

2163

_exit(EX_OSERR);

2164

}

2165

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

2166

if(ret == -1){

2167

free(delaystring);

2168

perror_plus("setenv");

2169

_exit(EX_OSERR);

2170

}

2171

free(delaystring);

2172

if(connect_to != NULL){

2173

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

2174

if(ret == -1){

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

}

2179

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

2180

direntry->d_name,

2181

O_RDONLY));

2182

if(hook_fd == -1){

2183

perror_plus("openat");

2184

_exit(EXIT_FAILURE);

2185

}

2186

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

2187

perror_plus("close");

2188

_exit(EXIT_FAILURE);

2189

}

2190

ret = dup2(devnull, STDIN_FILENO);

2191

if(ret == -1){

2192

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

2193

_exit(EX_OSERR);

2194

}

2195

ret = close(devnull);

2196

if(ret == -1){

2197

perror_plus("close");

2198

_exit(EX_OSERR);

2199

}

2200

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2201

if(ret == -1){

2202

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

2203

_exit(EX_OSERR);

2204

}

2205

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

2206

environ) == -1){

2207

perror_plus("fexecve");

2208

_exit(EXIT_FAILURE);

2209

}

2210

} else {

2211

if(hook_pid == -1){

2212

perror_plus("fork");

2213

free(direntry);

2214

continue;

2215

}

2216

int status;

2217

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

2218

perror_plus("waitpid");

2219

free(direntry);

2220

continue;

2221

}

2222

if(WIFEXITED(status)){

2223

if(WEXITSTATUS(status) != 0){

2224

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

2225

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

2226

WEXITSTATUS(status));

2227

free(direntry);

2228

continue;

2229

}

2230

} else if(WIFSIGNALED(status)){

2231

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

2232

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

2233

WTERMSIG(status));

2234

free(direntry);

2235

continue;

2236

} else {

2237

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

2238

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

2239

free(direntry);

2240

continue;

2241

}

2242

}

2243

if(debug){

2244

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

2245

direntry->d_name);

2246

}

2247

free(direntry);

2248

}

2249

free(direntries);

2250

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

2251

perror_plus("close");

2252

} else {

2253

hookdir_fd = -1;

2254

}

2255

close(devnull);

2256

}

2257

2258

__attribute__((nonnull, warn_unused_result))

2259

int bring_up_interface(const char *const interface,

2260

const float delay){

2261

int old_errno = errno;

2262

int ret;

2263

struct ifreq network;

2264

unsigned int if_index = if_nametoindex(interface);

2265

if(if_index == 0){

2266

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

2267

errno = old_errno;

2268

return ENXIO;

2269

}

2270

2271

if(quit_now){

2272

errno = old_errno;

2273

return EINTR;

2274

}

2275

2276

if(not interface_is_up(interface)){

2277

int ret_errno = 0;

2278

int ioctl_errno = 0;

2279

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

2280

ret_errno = errno;

2281

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

2282

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

2283

errno = old_errno;

2284

return ret_errno;

2285

}

2286

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

2287

2288

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

2289

if(sd == -1){

2290

ret_errno = errno;

2291

perror_plus("socket");

2292

errno = old_errno;

2293

return ret_errno;

2294

}

2295

2296

if(quit_now){

2297

ret = close(sd);

2298

if(ret == -1){

2299

perror_plus("close");

2300

}

2301

errno = old_errno;

2302

return EINTR;

2303

}

2304

2305

if(debug){

2306

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

2307

interface);

2308

}

2309

2310

/* Raise privileges */

2311

ret_errno = raise_privileges();

2312

if(ret_errno != 0){

2313

errno = ret_errno;

2314

perror_plus("Failed to raise privileges");

2315

}

2316

2317

#ifdef __linux__

2318

int ret_linux;

2319

bool restore_loglevel = false;

2320

if(ret_errno == 0){

2321

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2322

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

2323

ret_linux = klogctl(8, NULL, 5);

2324

if(ret_linux == -1){

2325

perror_plus("klogctl");

2326

} else {

2327

restore_loglevel = true;

2328

}

2329

}

2330

#endif /* __linux__ */

2331

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

2332

ioctl_errno = errno;

2333

#ifdef __linux__

2334

if(restore_loglevel){

2335

ret_linux = klogctl(7, NULL, 0);

2336

if(ret_linux == -1){

2337

perror_plus("klogctl");

2338

}

2339

}

2340

#endif /* __linux__ */

2341

2342

/* If raise_privileges() succeeded above */

2343

if(ret_errno == 0){

2344

/* Lower privileges */

2345

ret_errno = lower_privileges();

2346

if(ret_errno != 0){

2347

errno = ret_errno;

2348

perror_plus("Failed to lower privileges");

2349

}

2350

}

2351

2352

/* Close the socket */

2353

ret = close(sd);

2354

if(ret == -1){

2355

perror_plus("close");

2356

}

2357

2358

if(ret_setflags == -1){

2359

errno = ioctl_errno;

2360

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2361

errno = old_errno;

2362

return ioctl_errno;

2363

}

2364

} else if(debug){

2365

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

2366

interface);

2367

}

2368

2369

/* Sleep checking until interface is running.

2370

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

2371

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

2372

if(interface_is_running(interface)){

2373

break;

2374

}

2375

struct timespec sleeptime = { .tv_nsec = 250000000 };

2376

ret = nanosleep(&sleeptime, NULL);

2377

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

2378

perror_plus("nanosleep");

2379

}

2380

}

2381

2382

errno = old_errno;

2383

return 0;

2384

}

2385

2386

__attribute__((nonnull, warn_unused_result))

2387

int take_down_interface(const char *const interface){

2388

int old_errno = errno;

2389

struct ifreq network;

2390

unsigned int if_index = if_nametoindex(interface);

2391

if(if_index == 0){

2392

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

2393

errno = old_errno;

2394

return ENXIO;

2395

}

2396

if(interface_is_up(interface)){

2397

int ret_errno = 0;

2398

int ioctl_errno = 0;

2399

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

2400

ret_errno = errno;

2401

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

2402

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

2403

errno = old_errno;

2404

return ret_errno;

2405

}

2406

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

2407

2408

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

2409

if(sd == -1){

2410

ret_errno = errno;

2411

perror_plus("socket");

2412

errno = old_errno;

2413

return ret_errno;

2414

}

2415

2416

if(debug){

2417

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

2418

interface);

2419

}

2420

2421

/* Raise privileges */

2422

ret_errno = raise_privileges();

2423

if(ret_errno != 0){

2424

errno = ret_errno;

2425

perror_plus("Failed to raise privileges");

2426

}

2427

2428

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

2429

ioctl_errno = errno;

2430

2431

/* If raise_privileges() succeeded above */

2432

if(ret_errno == 0){

2433

/* Lower privileges */

2434

ret_errno = lower_privileges();

2435

if(ret_errno != 0){

2436

errno = ret_errno;

2437

perror_plus("Failed to lower privileges");

2438

}

2439

}

2440

2441

/* Close the socket */

2442

int ret = close(sd);

2443

if(ret == -1){

2444

perror_plus("close");

2445

}

2446

2447

if(ret_setflags == -1){

2448

errno = ioctl_errno;

2449

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2450

errno = old_errno;

2451

return ioctl_errno;

2452

}

2453

} else if(debug){

2454

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

2455

interface);

2456

}

2457

2458

errno = old_errno;

2459

return 0;

2460

}

2461

1264

2462

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

2463

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

2464

#if GNUTLS_VERSION_NUMBER >= 0x030606

2465

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

2466

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

2467

":%PROFILE_ULTRA",

2468

#elif GNUTLS_VERSION_NUMBER < 0x030600

2469

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

2470

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

2471

#else

2472

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

2473

#endif

2474

.current_server = NULL, .interfaces = NULL,

2475

.interfaces_size = 0 };

1265

2476

AvahiSServiceBrowser *sb = NULL;

1266

int error;

2477

error_t ret_errno;

1267

2478

int ret;

1268

2479

intmax_t tmpmax;

1269

2480

char *tmp;

1270

2481

int exitcode = EXIT_SUCCESS;

1271

const char *interface = "";

1272

struct ifreq network;

1273

int sd = -1;

1274

bool take_down_interface = false;

1275

uid_t uid;

1276

gid_t gid;

1277

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

1278

bool tempdir_created = false;

2482

char *interfaces_to_take_down = NULL;

2483

size_t interfaces_to_take_down_size = 0;

2484

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

2485

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

2486

char *tempdir = NULL;

1279

2487

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1280

2488

const char *seckey = PATHDIR "/" SECKEY;

1281

2489

const char *pubkey = PATHDIR "/" PUBKEY;

2490

#if GNUTLS_VERSION_NUMBER >= 0x030606

2491

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2492

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2493

#endif

2494

const char *dh_params_file = NULL;

2495

char *interfaces_hooks = NULL;

1282

2496

1283

2497

bool gnutls_initialized = false;

1284

2498

bool gpgme_initialized = false;

1285

2499

float delay = 2.5f;

1286

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

2500

double retry_interval = 10; /* 10s between trying a server and

2501

retrying the same server again */

1287

2502

1288

2503

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1289

2504

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1329

2544

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

1330

2545

.arg = "FILE",

1331

2546

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

1332

.group = 2 },

2547

.group = 1 },

2548

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

2549

.arg = "FILE",

2550

#if GNUTLS_VERSION_NUMBER >= 0x030606

2551

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

2552

#else

2553

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

2554

#endif

2555

.group = 1 },

2556

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

2557

.arg = "FILE",

2558

#if GNUTLS_VERSION_NUMBER >= 0x030606

2559

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

2560

#else

2561

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

2562

#endif

2563

.group = 1 },

1333

2564

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

1334

2565

.arg = "BITS",

1335

2566

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

1336

2567

" Diffie-Hellman key exchange",

1337

2568

.group = 2 },

2569

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

2570

.arg = "FILE",

2571

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

2572

" for the Diffie-Hellman key exchange",

2573

.group = 2 },

1338

2574

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

1339

2575

.arg = "STRING",

1340

2576

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

1345

2581

.group = 2 },

1346

2582

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

1347

2583

.arg = "SECONDS",

1348

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

2584

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

2585

.group = 2 },

2586

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

2587

.arg = "DIR",

2588

.doc = "Directory where network hooks are located",

1349

2589

.group = 2 },

1350

2590

/*

1351

2591

* These reproduce what we would get without ARGP_NO_HELP

1370

2610

connect_to = arg;

1371

2611

break;

1372

2612

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

1373

interface = arg;

2613

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

2614

arg, (int)',');

2615

if(ret_errno != 0){

2616

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

2617

}

1374

2618

break;

1375

2619

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

1376

2620

seckey = arg;

1378

2622

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

1379

2623

pubkey = arg;

1380

2624

break;

2625

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

2626

#if GNUTLS_VERSION_NUMBER >= 0x030606

2627

tls_privkey = arg;

2628

#endif

2629

break;

2630

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

2631

#if GNUTLS_VERSION_NUMBER >= 0x030606

2632

tls_pubkey = arg;

2633

#endif

2634

break;

1381

2635

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

1382

2636

errno = 0;

1383

2637

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

1387

2641

}

1388

2642

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

1389

2643

break;

2644

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

2645

dh_params_file = arg;

2646

break;

1390

2647

case 130: /* --priority */

1391

2648

mc.priority = arg;

1392

2649

break;

1400

2657

errno = 0;

1401

2658

retry_interval = strtod(arg, &tmp);

1402

2659

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

1403

or (retry_interval * 1000) > INT_MAX){

2660

or (retry_interval * 1000) > INT_MAX

2661

or retry_interval < 0){

1404

2662

argp_error(state, "Bad retry interval");

1405

2663

}

1406

2664

break;

2665

case 133: /* --network-hook-dir */

2666

hookdir = arg;

2667

break;

1407

2668

/*

1408

2669

* These reproduce what we would get without ARGP_NO_HELP

1409

2670

*/

1411

2672

argp_state_help(state, state->out_stream,

1412

2673

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1413

2674

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2675

__builtin_unreachable();

1414

2676

case -3: /* --usage */

1415

2677

argp_state_help(state, state->out_stream,

1416

2678

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2679

__builtin_unreachable();

1417

2680

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

1418

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

2681

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

1419

2682

exit(argp_err_exit_status);

1420

2683

break;

1421

2684

default:

1428

2691

.args_doc = "",

1429

2692

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

1430

2693

" passwords from a Mandos server" };

1431

ret = argp_parse(&argp, argc, argv,

1432

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1433

switch(ret){

2694

ret_errno = argp_parse(&argp, argc, argv,

2695

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2696

switch(ret_errno){

1434

2697

case 0:

1435

2698

break;

1436

2699

case ENOMEM:

1437

2700

default:

1438

errno = ret;

2701

errno = ret_errno;

1439

2702

perror_plus("argp_parse");

1440

2703

exitcode = EX_OSERR;

1441

2704

goto end;

1445

2708

}

1446

2709

}

1447

2710

2711

{

2712

/* Work around Debian bug #633582:

2713

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

2714

2715

/* Re-raise privileges */

2716

ret = raise_privileges();

2717

if(ret != 0){

2718

errno = ret;

2719

perror_plus("Failed to raise privileges");

2720

} else {

2721

struct stat st;

2722

2723

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

2724

int seckey_fd = open(seckey, O_RDONLY);

2725

if(seckey_fd == -1){

2726

perror_plus("open");

2727

} else {

2728

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

2729

if(ret == -1){

2730

perror_plus("fstat");

2731

} else {

2732

if(S_ISREG(st.st_mode)

2733

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

2734

ret = fchown(seckey_fd, uid, gid);

2735

if(ret == -1){

2736

perror_plus("fchown");

2737

}

2738

}

2739

}

2740

close(seckey_fd);

2741

}

2742

}

2743

2744

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

2745

int pubkey_fd = open(pubkey, O_RDONLY);

2746

if(pubkey_fd == -1){

2747

perror_plus("open");

2748

} else {

2749

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

2750

if(ret == -1){

2751

perror_plus("fstat");

2752

} else {

2753

if(S_ISREG(st.st_mode)

2754

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

2755

ret = fchown(pubkey_fd, uid, gid);

2756

if(ret == -1){

2757

perror_plus("fchown");

2758

}

2759

}

2760

}

2761

close(pubkey_fd);

2762

}

2763

}

2764

2765

if(dh_params_file != NULL

2766

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

2767

int dhparams_fd = open(dh_params_file, O_RDONLY);

2768

if(dhparams_fd == -1){

2769

perror_plus("open");

2770

} else {

2771

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

2772

if(ret == -1){

2773

perror_plus("fstat");

2774

} else {

2775

if(S_ISREG(st.st_mode)

2776

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

2777

ret = fchown(dhparams_fd, uid, gid);

2778

if(ret == -1){

2779

perror_plus("fchown");

2780

}

2781

}

2782

}

2783

close(dhparams_fd);

2784

}

2785

}

2786

2787

/* Lower privileges */

2788

ret = lower_privileges();

2789

if(ret != 0){

2790

errno = ret;

2791

perror_plus("Failed to lower privileges");

2792

}

2793

}

2794

}

2795

2796

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

2797

{

2798

char *interface = NULL;

2799

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

2800

interface))){

2801

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

2802

and if_nametoindex(interface) == 0){

2803

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

2804

fprintf_plus(stderr, "Not using nonexisting interface"

2805

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

2806

}

2807

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

2808

interface = NULL;

2809

}

2810

}

2811

}

2812

2813

/* Run network hooks */

2814

{

2815

if(mc.interfaces != NULL){

2816

interfaces_hooks = malloc(mc.interfaces_size);

2817

if(interfaces_hooks == NULL){

2818

perror_plus("malloc");

2819

goto end;

2820

}

2821

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

2822

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

2823

}

2824

run_network_hooks("start", interfaces_hooks != NULL ?

2825

interfaces_hooks : "", delay);

2826

}

2827

1448

2828

if(not debug){

1449

2829

avahi_set_log_function(empty_log);

1450

2830

}

1451

1452

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

1453

struct dirent **direntries;

1454

ret = scandir(sys_class_net, &direntries, good_interface,

1455

alphasort);

1456

if(ret >= 1){

1457

/* Pick the first good interface */

1458

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

1459

if(debug){

1460

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

1461

}

1462

if(interface == NULL){

1463

perror_plus("malloc");

1464

free(direntries);

1465

exitcode = EXIT_FAILURE;

1466

goto end;

1467

}

1468

free(direntries);

1469

} else {

1470

free(direntries);

1471

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

1472

exitcode = EXIT_FAILURE;

1473

goto end;

1474

}

1475

}

1476

2831

1477

2832

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

1478

2833

from the signal handler */

1479

2834

/* Initialize the pseudo-RNG for Avahi */

1480

2835

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

1481

mc.simple_poll = avahi_simple_poll_new();

1482

if(mc.simple_poll == NULL){

1483

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

2836

simple_poll = avahi_simple_poll_new();

2837

if(simple_poll == NULL){

2838

fprintf_plus(stderr,

2839

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

1484

2840

exitcode = EX_UNAVAILABLE;

1485

2841

goto end;

1486

2842

}

1548

2904

}

1549

2905

}

1550

2906

1551

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

1552

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

1553

if_index = (AvahiIfIndex) if_nametoindex(interface);

1554

if(if_index == 0){

1555

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

1556

exitcode = EX_UNAVAILABLE;

1557

goto end;

1558

}

1559

1560

if(quit_now){

1561

goto end;

1562

}

1563

1564

/* Re-raise priviliges */

1565

errno = 0;

1566

ret = seteuid(0);

1567

if(ret == -1){

1568

perror_plus("seteuid");

1569

}

1570

1571

#ifdef __linux__

1572

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1573

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

1574

ret = klogctl(8, NULL, 5);

1575

bool restore_loglevel = true;

1576

if(ret == -1){

1577

restore_loglevel = false;

1578

perror_plus("klogctl");

1579

}

1580

#endif /* __linux__ */

1581

1582

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1583

if(sd < 0){

1584

perror_plus("socket");

1585

exitcode = EX_OSERR;

1586

#ifdef __linux__

1587

if(restore_loglevel){

1588

ret = klogctl(7, NULL, 0);

1589

if(ret == -1){

1590

perror_plus("klogctl");

1591

}

1592

}

1593

#endif /* __linux__ */

1594

/* Lower privileges */

1595

errno = 0;

1596

ret = seteuid(uid);

1597

if(ret == -1){

1598

perror_plus("seteuid");

1599

}

1600

goto end;

1601

}

1602

strcpy(network.ifr_name, interface);

1603

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

1604

if(ret == -1){

1605

perror_plus("ioctl SIOCGIFFLAGS");

1606

#ifdef __linux__

1607

if(restore_loglevel){

1608

ret = klogctl(7, NULL, 0);

1609

if(ret == -1){

1610

perror_plus("klogctl");

1611

}

1612

}

1613

#endif /* __linux__ */

1614

exitcode = EX_OSERR;

1615

/* Lower privileges */

1616

errno = 0;

1617

ret = seteuid(uid);

1618

if(ret == -1){

1619

perror_plus("seteuid");

1620

}

1621

goto end;

1622

}

1623

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

1624

network.ifr_flags |= IFF_UP;

1625

take_down_interface = true;

1626

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

1627

if(ret == -1){

1628

take_down_interface = false;

1629

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1630

exitcode = EX_OSERR;

1631

#ifdef __linux__

1632

if(restore_loglevel){

1633

ret = klogctl(7, NULL, 0);

1634

if(ret == -1){

1635

perror_plus("klogctl");

2907

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

2908

if(mc.interfaces == NULL){

2909

struct dirent **direntries = NULL;

2910

/* Look for any good interfaces */

2911

ret = scandir(sys_class_net, &direntries, good_interface,

2912

alphasort);

2913

if(ret >= 1){

2914

/* Add all found interfaces to interfaces list */

2915

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

2916

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

2917

direntries[i]->d_name);

2918

if(ret_errno != 0){

2919

errno = ret_errno;

2920

perror_plus("argz_add");

2921

free(direntries[i]);

2922

continue;

2923

}

2924

if(debug){

2925

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

2926

direntries[i]->d_name);

2927

}

2928

free(direntries[i]);

2929

}

2930

free(direntries);

2931

} else {

2932

if(ret == 0){

2933

free(direntries);

2934

}

2935

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

2936

exitcode = EXIT_FAILURE;

2937

goto end;

2938

}

2939

}

2940

2941

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

2942

{

2943

char *interface = NULL;

2944

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

2945

interface))){

2946

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

2947

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

2948

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

2949

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

2950

interface);

2951

interface = NULL;

2952

while((interface = argz_next(mc.interfaces,

2953

mc.interfaces_size, interface))){

2954

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

2955

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

2956

interface);

2957

interface = NULL;

1636

2958

}

1637

2959

}

1638

#endif /* __linux__ */

1639

/* Lower privileges */

1640

errno = 0;

1641

ret = seteuid(uid);

1642

if(ret == -1){

1643

perror_plus("seteuid");

1644

}

1645

goto end;

1646

}

1647

}

1648

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

1649

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

1650

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

1651

if(ret == -1){

1652

perror_plus("ioctl SIOCGIFFLAGS");

1653

} else if(network.ifr_flags & IFF_RUNNING){

1654

2960

break;

1655

2961

}

1656

struct timespec sleeptime = { .tv_nsec = 250000000 };

1657

ret = nanosleep(&sleeptime, NULL);

1658

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

1659

perror_plus("nanosleep");

1660

}

1661

}

1662

if(not take_down_interface){

1663

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

1664

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

1665

if(ret == -1){

1666

perror_plus("close");

1667

}

1668

}

1669

#ifdef __linux__

1670

if(restore_loglevel){

1671

/* Restores kernel loglevel to default */

1672

ret = klogctl(7, NULL, 0);

1673

if(ret == -1){

1674

perror_plus("klogctl");

1675

}

1676

}

1677

#endif /* __linux__ */

1678

/* Lower privileges */

1679

errno = 0;

1680

if(take_down_interface){

1681

/* Lower privileges */

1682

ret = seteuid(uid);

1683

if(ret == -1){

1684

perror_plus("seteuid");

1685

}

1686

} else {

1687

/* Lower privileges permanently */

1688

ret = setuid(uid);

1689

if(ret == -1){

1690

perror_plus("setuid");

1691

}

1692

}

2962

bool interface_was_up = interface_is_up(interface);

2963

errno = bring_up_interface(interface, delay);

2964

if(not interface_was_up){

2965

if(errno != 0){

2966

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

2967

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

2968

} else {

2969

errno = argz_add(&interfaces_to_take_down,

2970

&interfaces_to_take_down_size,

2971

interface);

2972

if(errno != 0){

2973

perror_plus("argz_add");

2974

}

2975

}

2976

}

2977

}

2978

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

2979

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

2980

}

2981

}

2982

2983

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

2984

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

2985

if(debug){

2986

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

2987

mc.interfaces);

2988

}

2989

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

1693

2990

}

1694

2991

1695

2992

if(quit_now){

1696

2993

goto end;

1697

2994

}

1698

2995

1699

ret = init_gnutls_global(pubkey, seckey);

2996

#if GNUTLS_VERSION_NUMBER >= 0x030606

2997

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

2998

#elif GNUTLS_VERSION_NUMBER < 0x030600

2999

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

3000

#else

3001

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

3002

#endif

1700

3003

if(ret == -1){

1701

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

3004

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

1702

3005

exitcode = EX_UNAVAILABLE;

1703

3006

goto end;

1704

3007

} else {

1709

3012

goto end;

1710

3013

}

1711

3014

1712

if(mkdtemp(tempdir) == NULL){

3015

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

3016

tempdir = mkdtemp(run_tempdir);

3017

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

3018

if(debug){

3019

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

3020

run_tempdir, old_tempdir);

3021

}

3022

tempdir = mkdtemp(old_tempdir);

3023

}

3024

if(tempdir == NULL){

1713

3025

perror_plus("mkdtemp");

1714

3026

goto end;

1715

3027

}

1716

tempdir_created = true;

1717

3028

1718

3029

if(quit_now){

1719

3030

goto end;

1720

3031

}

1721

3032

1722

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

1723

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

3033

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

3034

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

1724

3035

exitcode = EX_UNAVAILABLE;

1725

3036

goto end;

1726

3037

} else {

1735

3046

/* Connect directly, do not use Zeroconf */

1736

3047

/* (Mainly meant for debugging) */

1737

3048

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

3049

1738

3050

if(address == NULL){

1739

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

3051

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

1740

3052

exitcode = EX_USAGE;

1741

3053

goto end;

1742

3054

}

1745

3057

goto end;

1746

3058

}

1747

3059

1748

uint16_t port;

3060

in_port_t port;

1749

3061

errno = 0;

1750

3062

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

1751

3063

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

1752

or tmpmax != (uint16_t)tmpmax){

1753

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

3064

or tmpmax != (in_port_t)tmpmax){

3065

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

1754

3066

exitcode = EX_USAGE;

1755

3067

goto end;

1756

3068

}

1757

3069

1758

3070

if(quit_now){

1759

3071

goto end;

1760

3072

}

1761

3073

1762

port = (uint16_t)tmpmax;

3074

port = (in_port_t)tmpmax;

1763

3075

*address = '\0';

1764

address = connect_to;

1765

3076

/* Colon in address indicates IPv6 */

1766

3077

int af;

1767

if(strchr(address, ':') != NULL){

3078

if(strchr(connect_to, ':') != NULL){

1768

3079

af = AF_INET6;

3080

/* Accept [] around IPv6 address - see RFC 5952 */

3081

if(connect_to[0] == '[' and address[-1] == ']')

3082

{

3083

connect_to++;

3084

address[-1] = '\0';

3085

}

1769

3086

} else {

1770

3087

af = AF_INET;

1771

3088

}

3089

address = connect_to;

1772

3090

1773

3091

if(quit_now){

1774

3092

goto end;

1775

3093

}

1776

3094

1777

3095

while(not quit_now){

1778

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

3096

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

3097

&mc);

1779

3098

if(quit_now or ret == 0){

1780

3099

break;

1781

3100

}

1782

sleep((int)retry_interval or 1);

1783

};

1784

1785

if (not quit_now){

3101

if(debug){

3102

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

3103

(int)retry_interval);

3104

}

3105

sleep((unsigned int)retry_interval);

3106

}

3107

3108

if(not quit_now){

1786

3109

exitcode = EXIT_SUCCESS;

1787

3110

}

1788

3111

1789

3112

goto end;

1790

3113

}

1791

3114

1803

3126

config.publish_domain = 0;

1804

3127

1805

3128

/* Allocate a new server */

1806

mc.server = avahi_server_new(avahi_simple_poll_get

1807

(mc.simple_poll), &config, NULL,

1808

NULL, &error);

3129

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3130

&config, NULL, NULL, &ret);

1809

3131

1810

3132

/* Free the Avahi configuration data */

1811

3133

avahi_server_config_free(&config);

1813

3135

1814

3136

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

1815

3137

if(mc.server == NULL){

1816

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

1817

avahi_strerror(error));

3138

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

3139

avahi_strerror(ret));

1818

3140

exitcode = EX_UNAVAILABLE;

1819

3141

goto end;

1820

3142

}

1826

3148

/* Create the Avahi service browser */

1827

3149

sb = avahi_s_service_browser_new(mc.server, if_index,

1828

3150

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1829

NULL, 0, browse_callback, NULL);

3151

NULL, 0, browse_callback,

3152

(void *)&mc);

1830

3153

if(sb == NULL){

1831

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

1832

avahi_strerror(avahi_server_errno(mc.server)));

3154

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

3155

avahi_strerror(avahi_server_errno(mc.server)));

1833

3156

exitcode = EX_UNAVAILABLE;

1834

3157

goto end;

1835

3158

}

1841

3164

/* Run the main loop */

1842

3165

1843

3166

if(debug){

1844

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

3167

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

1845

3168

}

1846

1847

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

3169

3170

ret = avahi_loop_with_timeout(simple_poll,

3171

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

1848

3172

if(debug){

1849

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

1850

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

3173

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

3174

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

1851

3175

}

1852

3176

1853

3177

end:

1854

3178

1855

3179

if(debug){

1856

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

3180

if(signal_received){

3181

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

3182

argv[0], signal_received,

3183

strsignal(signal_received));

3184

} else {

3185

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

3186

}

1857

3187

}

1858

3188

1859

3189

/* Cleanup things */

3190

free(mc.interfaces);

3191

1860

3192

if(sb != NULL)

1861

3193

avahi_s_service_browser_free(sb);

1862

3194

1863

3195

if(mc.server != NULL)

1864

3196

avahi_server_free(mc.server);

1865

3197

1866

if(mc.simple_poll != NULL)

1867

avahi_simple_poll_free(mc.simple_poll);

3198

if(simple_poll != NULL)

3199

avahi_simple_poll_free(simple_poll);

1868

3200

1869

3201

if(gnutls_initialized){

1870

3202

gnutls_certificate_free_credentials(mc.cred);

1871

gnutls_global_deinit();

1872

3203

gnutls_dh_params_deinit(mc.dh_params);

1873

3204

}

1874

3205

1875

3206

if(gpgme_initialized){

1876

3207

gpgme_release(mc.ctx);

1877

3208

}

1878

1879

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

3209

3210

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

3211

has seen */

1880

3212

if(mc.current_server != NULL){

1881

3213

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

1882

3214

while(mc.current_server != NULL){

1883

3215

server *next = mc.current_server->next;

3216

#ifdef __GNUC__

3217

#pragma GCC diagnostic push

3218

#pragma GCC diagnostic ignored "-Wcast-qual"

3219

#endif

3220

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

3221

#ifdef __GNUC__

3222

#pragma GCC diagnostic pop

3223

#endif

1884

3224

free(mc.current_server);

1885

3225

mc.current_server = next;

1886

3226

}

1887

3227

}

1888

3228

1889

/* Take down the network interface */

1890

if(take_down_interface){

1891

/* Re-raise priviliges */

1892

errno = 0;

1893

ret = seteuid(0);

1894

if(ret == -1){

1895

perror_plus("seteuid");

1896

}

1897

if(geteuid() == 0){

1898

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

1899

if(ret == -1){

1900

perror_plus("ioctl SIOCGIFFLAGS");

1901

} else if(network.ifr_flags & IFF_UP) {

1902

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

1903

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

1904

if(ret == -1){

1905

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1906

}

1907

}

1908

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

1909

if(ret == -1){

1910

perror_plus("close");

1911

}

1912

/* Lower privileges permanently */

1913

errno = 0;

1914

ret = setuid(uid);

1915

if(ret == -1){

1916

perror_plus("setuid");

1917

}

1918

}

3229

/* Re-raise privileges */

3230

{

3231

ret = raise_privileges();

3232

if(ret != 0){

3233

errno = ret;

3234

perror_plus("Failed to raise privileges");

3235

} else {

3236

3237

/* Run network hooks */

3238

run_network_hooks("stop", interfaces_hooks != NULL ?

3239

interfaces_hooks : "", delay);

3240

3241

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

3242

{

3243

char *interface = NULL;

3244

while((interface = argz_next(interfaces_to_take_down,

3245

interfaces_to_take_down_size,

3246

interface))){

3247

ret = take_down_interface(interface);

3248

if(ret != 0){

3249

errno = ret;

3250

perror_plus("Failed to take down interface");

3251

}

3252

}

3253

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

3254

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

3255

" down\n");

3256

}

3257

}

3258

}

3259

3260

ret = lower_privileges_permanently();

3261

if(ret != 0){

3262

errno = ret;

3263

perror_plus("Failed to lower privileges permanently");

3264

}

3265

}

3266

3267

free(interfaces_to_take_down);

3268

free(interfaces_hooks);

3269

3270

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

3271

uintmax_t level){

3272

struct dirent **direntries = NULL;

3273

int dret;

3274

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

3275

O_RDONLY

3276

| O_NOFOLLOW

3277

| O_DIRECTORY

3278

| O_PATH));

3279

if(dir_fd == -1){

3280

perror_plus("open");

3281

return;

3282

}

3283

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

3284

notdotentries, alphasort);

3285

if(numentries >= 0){

3286

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

3287

if(debug){

3288

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

3289

dirname, direntries[i]->d_name);

3290

}

3291

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

3292

if(dret == -1){

3293

if(errno == EISDIR){

3294

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

3295

AT_REMOVEDIR);

3296

}

3297

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

3298

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

3299

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

3300

/* Recurse only in this special case */

3301

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

3302

dret = 0;

3303

}

3304

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

3305

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

3306

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

3307

}

3308

}

3309

free(direntries[i]);

3310

}

3311

3312

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

3313

free(direntries);

3314

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3315

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

3316

perror_plus("rmdir");

3317

}

3318

} else {

3319

perror_plus("scandirat");

3320

}

3321

close(dir_fd);

1919

3322

}

1920

3323

1921

3324

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

1922

if(tempdir_created){

1923

struct dirent **direntries = NULL;

1924

struct dirent *direntry = NULL;

1925

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

1926

if (ret > 0){

1927

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

1928

direntry = direntries[i];

1929

char *fullname = NULL;

1930

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

1931

direntry->d_name);

1932

if(ret < 0){

1933

perror_plus("asprintf");

1934

continue;

1935

}

1936

ret = remove(fullname);

1937

if(ret == -1){

1938

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

1939

strerror(errno));

1940

}

1941

free(fullname);

1942

}

1943

}

1944

1945

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

1946

free(direntries);

1947

if (ret == -1){

1948

perror_plus("scandir");

1949

}

1950

ret = rmdir(tempdir);

1951

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

1952

perror_plus("rmdir");

1953

}

3325

if(tempdir != NULL){

3326

clean_dir_at(-1, tempdir, 0);

1954

3327

}

1955

3328

1956

3329

if(quit_now){