/mandos/release : revision 237.7.498

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 */

66

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

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 */

73

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

67

74

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

68

75

SIOCSIFFLAGS, if_indextoname(),

69

76

if_nametoindex(), IF_NAMESIZE */

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() */

107

124

init_gnutls_session(),

108

125

GNUTLS_* */

109

126

#include <gnutls/openpgp.h>

110

/* gnutls_certificate_set_openpgp_key_file(),

111

GNUTLS_OPENPGP_FMT_BASE64 */

127

/* gnutls_certificate_set_openpgp_key_file(),

128

GNUTLS_OPENPGP_FMT_BASE64 */

112

129

113

130

/* GPGME */

114

131

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

122

139

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

123

140

#define SECKEY "seckey.txt"

124

141

#define PUBKEY "pubkey.txt"

142

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

125

143

126

144

bool debug = false;

127

145

static const char mandos_protocol_version[] = "1";

128

146

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

129

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

147

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

130

148

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

131

149

char *connect_to = NULL;

150

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

152

uid_t uid = 65534;

153

gid_t gid = 65534;

154

155

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

156

typedef struct server{

157

const char *ip;

158

in_port_t port;

159

AvahiIfIndex if_index;

160

int af;

161

struct timespec last_seen;

162

struct server *next;

163

struct server *prev;

164

} server;

132

165

133

166

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

134

167

typedef struct {

135

AvahiSimplePoll *simple_poll;

136

168

AvahiServer *server;

137

169

gnutls_certificate_credentials_t cred;

138

170

unsigned int dh_bits;

139

171

gnutls_dh_params_t dh_params;

140

172

const char *priority;

141

173

gpgme_ctx_t ctx;

174

server *current_server;

175

char *interfaces;

176

size_t interfaces_size;

142

177

} mandos_context;

143

178

144

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

145

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

146

.dh_bits = 1024, .priority = "SECURE256"

147

":!CTYPE-X.509:+CTYPE-OPENPGP" };

179

/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

148

181

149

182

sig_atomic_t quit_now = 0;

150

183

int signal_received = 0;

151

184

185

/* Function to use when printing errors */

186

void perror_plus(const char *print_text){

187

int e = errno;

188

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

189

program_invocation_short_name);

190

errno = e;

191

perror(print_text);

192

}

193

194

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

195

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

196

va_list ap;

197

va_start (ap, format);

198

199

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

200

program_invocation_short_name));

201

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

202

}

203

152

204

/*

153

205

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

154

206

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

155

207

* "buffer_length" is how much is already used.

156

208

*/

209

__attribute__((nonnull, warn_unused_result))

157

210

size_t incbuffer(char **buffer, size_t buffer_length,

158

size_t buffer_capacity){

211

size_t buffer_capacity){

159

212

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

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

161

if(buffer == NULL){

213

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

214

if(new_buf == NULL){

215

int old_errno = errno;

216

free(*buffer);

217

errno = old_errno;

218

*buffer = NULL;

162

219

return 0;

163

220

}

221

*buffer = new_buf;

164

222

buffer_capacity += BUFFER_SIZE;

165

223

}

166

224

return buffer_capacity;

167

225

}

168

226

227

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

228

__attribute__((nonnull, warn_unused_result))

229

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

230

int af, server **current_server){

231

int ret;

232

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

233

if(new_server == NULL){

234

perror_plus("malloc");

235

return false;

236

}

237

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

238

.port = port,

239

.if_index = if_index,

240

.af = af };

241

if(new_server->ip == NULL){

242

perror_plus("strdup");

243

free(new_server);

244

return false;

245

}

246

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

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

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

return false;

259

}

260

/* Special case of first server */

261

if(*current_server == NULL){

262

new_server->next = new_server;

263

new_server->prev = new_server;

264

*current_server = new_server;

265

} else {

266

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

267

new_server->next = *current_server;

268

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

269

new_server->prev->next = new_server;

270

(*current_server)->prev = new_server;

271

}

272

return true;

273

}

274

169

275

/*

170

276

* Initialize GPGME.

171

277

*/

172

static bool init_gpgme(const char *seckey,

173

const char *pubkey, const char *tempdir){

278

__attribute__((nonnull, warn_unused_result))

279

static bool init_gpgme(const char * const seckey,

280

const char * const pubkey,

281

const char * const tempdir,

282

mandos_context *mc){

174

283

gpgme_error_t rc;

175

284

gpgme_engine_info_t engine_info;

176

285

177

178

286

/*

179

287

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

180

288

*/

181

bool import_key(const char *filename){

289

bool import_key(const char * const filename){

182

290

int ret;

183

291

int fd;

184

292

gpgme_data_t pgp_data;

185

293

186

294

fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

187

295

if(fd == -1){

188

perror("open");

296

perror_plus("open");

189

297

return false;

190

298

}

191

299

192

300

rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

301

if(rc != GPG_ERR_NO_ERROR){

194

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

195

gpgme_strsource(rc), gpgme_strerror(rc));

302

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

303

gpgme_strsource(rc), gpgme_strerror(rc));

196

304

return false;

197

305

}

198

306

199

rc = gpgme_op_import(mc.ctx, pgp_data);

307

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

200

308

if(rc != GPG_ERR_NO_ERROR){

201

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

202

gpgme_strsource(rc), gpgme_strerror(rc));

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

203

311

return false;

204

312

}

313

{

314

gpgme_import_result_t import_result

315

= gpgme_op_import_result(mc->ctx);

316

if((import_result->imported < 1

317

or import_result->not_imported > 0)

318

and import_result->unchanged == 0){

319

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

320

fprintf_plus(stderr,

321

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

322

import_result->considered);

323

fprintf_plus(stderr,

324

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

325

import_result->no_user_id);

326

fprintf_plus(stderr,

327

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

328

import_result->imported);

329

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

330

import_result->imported_rsa);

331

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

332

import_result->unchanged);

333

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

334

import_result->new_user_ids);

335

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

336

import_result->new_sub_keys);

337

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

338

import_result->new_signatures);

339

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

340

import_result->new_revocations);

341

fprintf_plus(stderr,

342

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

343

import_result->secret_read);

344

fprintf_plus(stderr,

345

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

346

import_result->secret_imported);

347

fprintf_plus(stderr,

348

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

349

import_result->secret_unchanged);

350

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

351

import_result->not_imported);

352

for(gpgme_import_status_t import_status

353

= import_result->imports;

354

import_status != NULL;

355

import_status = import_status->next){

356

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

357

import_status->fpr);

358

if(import_status->result != GPG_ERR_NO_ERROR){

359

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

360

gpgme_strsource(import_status->result),

361

gpgme_strerror(import_status->result));

362

}

363

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

364

fprintf_plus(stderr,

365

import_status->status & GPGME_IMPORT_NEW

366

? "The key was new.\n"

367

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

368

fprintf_plus(stderr,

369

import_status->status & GPGME_IMPORT_UID

370

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

371

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

372

fprintf_plus(stderr,

373

import_status->status & GPGME_IMPORT_SIG

374

? "The key contained new signatures.\n"

375

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

376

fprintf_plus(stderr,

377

import_status->status & GPGME_IMPORT_SUBKEY

378

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

379

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

380

fprintf_plus(stderr,

381

import_status->status & GPGME_IMPORT_SECRET

382

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

383

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

384

}

385

return false;

386

}

387

}

205

388

206

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

389

ret = close(fd);

207

390

if(ret == -1){

208

perror("close");

391

perror_plus("close");

209

392

}

210

393

gpgme_data_release(pgp_data);

211

394

return true;

212

395

}

213

396

214

397

if(debug){

215

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

398

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

216

399

}

217

400

218

401

/* Init GPGME */

219

402

gpgme_check_version(NULL);

220

403

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

221

404

if(rc != GPG_ERR_NO_ERROR){

222

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

223

gpgme_strsource(rc), gpgme_strerror(rc));

405

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

406

gpgme_strsource(rc), gpgme_strerror(rc));

224

407

return false;

225

408

}

226

409

227

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

410

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

228

411

rc = gpgme_get_engine_info(&engine_info);

229

412

if(rc != GPG_ERR_NO_ERROR){

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

413

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

414

gpgme_strsource(rc), gpgme_strerror(rc));

232

415

return false;

233

416

}

234

417

while(engine_info != NULL){

240

423

engine_info = engine_info->next;

241

424

}

242

425

if(engine_info == NULL){

243

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

426

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

427

tempdir);

244

428

return false;

245

429

}

246

430

247

431

/* Create new GPGME "context" */

248

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

432

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

249

433

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

434

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

435

gpgme_strsource(rc), gpgme_strerror(rc));

252

436

return false;

253

437

}

254

438

263

447

* Decrypt OpenPGP data.

264

448

* Returns -1 on error

265

449

*/

450

__attribute__((nonnull, warn_unused_result))

266

451

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

452

size_t crypto_size,

268

char **plaintext){

453

char **plaintext,

454

mandos_context *mc){

269

455

gpgme_data_t dh_crypto, dh_plain;

270

456

gpgme_error_t rc;

271

457

ssize_t ret;

273

459

ssize_t plaintext_length = 0;

274

460

275

461

if(debug){

276

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

462

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

277

463

}

278

464

279

465

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

280

466

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

467

0);

282

468

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

469

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

470

gpgme_strsource(rc), gpgme_strerror(rc));

285

471

return -1;

286

472

}

287

473

288

474

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

289

475

rc = gpgme_data_new(&dh_plain);

290

476

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

477

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

478

gpgme_strsource(rc), gpgme_strerror(rc));

293

479

gpgme_data_release(dh_crypto);

294

480

return -1;

295

481

}

296

482

297

483

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

298

484

data buffer */

299

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

485

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

300

486

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

487

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

488

gpgme_strsource(rc), gpgme_strerror(rc));

303

489

plaintext_length = -1;

304

490

if(debug){

305

491

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

492

result = gpgme_op_decrypt_result(mc->ctx);

307

493

if(result == NULL){

308

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

494

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

309

495

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

496

if(result->unsupported_algorithm != NULL) {

497

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

498

result->unsupported_algorithm);

499

}

500

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

501

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

314

502

if(result->file_name != NULL){

315

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

503

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

316

504

}

317

gpgme_recipient_t recipient;

318

recipient = result->recipients;

319

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

326

recipient = recipient->next;

505

506

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

507

r = r->next){

508

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

509

gpgme_pubkey_algo_name(r->pubkey_algo));

510

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

511

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

512

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

327

513

}

328

514

}

329

515

}

331

517

}

332

518

333

519

if(debug){

334

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

520

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

335

521

}

336

522

337

523

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

338

524

if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){

339

perror("gpgme_data_seek");

525

perror_plus("gpgme_data_seek");

340

526

plaintext_length = -1;

341

527

goto decrypt_end;

342

528

}

344

530

*plaintext = NULL;

345

531

while(true){

346

532

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

533

(size_t)plaintext_length,

534

plaintext_capacity);

349

535

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

536

perror_plus("incbuffer");

537

plaintext_length = -1;

538

goto decrypt_end;

353

539

}

354

540

355

541

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

546

break;

361

547

}

362

548

if(ret < 0){

363

perror("gpgme_data_read");

549

perror_plus("gpgme_data_read");

364

550

plaintext_length = -1;

365

551

goto decrypt_end;

366

552

}

368

554

}

369

555

370

556

if(debug){

371

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

557

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

372

558

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

373

559

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

374

560

}

385

571

return plaintext_length;

386

572

}

387

573

388

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

391

if(ret == NULL)

392

ret = "(unknown)";

393

return ret;

574

__attribute__((warn_unused_result, const))

575

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

576

if(str == NULL)

577

return "(unknown)";

578

return str;

579

}

580

581

__attribute__((warn_unused_result))

582

static const char *safer_gnutls_strerror(int value){

583

const char *ret = gnutls_strerror(value);

584

return safe_string(ret);

394

585

}

395

586

396

587

/* GnuTLS log function callback */

588

__attribute__((nonnull))

397

589

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

398

590

const char* string){

399

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

591

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

400

592

}

401

593

594

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

402

595

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

596

const char *seckeyfilename,

597

const char *dhparamsfilename,

598

mandos_context *mc){

404

599

int ret;

600

unsigned int uret;

405

601

406

602

if(debug){

407

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

408

}

409

410

ret = gnutls_global_init();

411

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

414

return -1;

603

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

415

604

}

416

605

417

606

if(debug){

423

612

}

424

613

425

614

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

615

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

616

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

433

gnutls_global_deinit();

617

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

618

safer_gnutls_strerror(ret));

434

619

return -1;

435

620

}

436

621

437

622

if(debug){

438

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

439

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

440

seckeyfilename);

623

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

624

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

625

pubkeyfilename,

626

seckeyfilename);

441

627

}

442

628

443

629

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

630

(mc->cred, pubkeyfilename, seckeyfilename,

445

631

GNUTLS_OPENPGP_FMT_BASE64);

446

632

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

633

fprintf_plus(stderr,

634

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

635

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

636

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

637

safer_gnutls_strerror(ret));

452

638

goto globalfail;

453

639

}

454

640

455

641

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

457

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

460

goto globalfail;

461

}

462

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

463

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

466

goto globalfail;

467

}

468

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

642

ret = gnutls_dh_params_init(&mc->dh_params);

643

if(ret != GNUTLS_E_SUCCESS){

644

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

645

" initialization: %s\n",

646

safer_gnutls_strerror(ret));

647

goto globalfail;

648

}

649

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

650

if(dhparamsfilename != NULL){

651

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

652

do {

653

int dhpfile = open(dhparamsfilename, O_RDONLY);

654

if(dhpfile == -1){

655

perror_plus("open");

656

dhparamsfilename = NULL;

657

break;

658

}

659

size_t params_capacity = 0;

660

while(true){

661

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

662

(size_t)params.size,

663

(size_t)params_capacity);

664

if(params_capacity == 0){

665

perror_plus("incbuffer");

666

free(params.data);

667

params.data = NULL;

668

dhparamsfilename = NULL;

669

break;

670

}

671

ssize_t bytes_read = read(dhpfile,

672

params.data + params.size,

673

BUFFER_SIZE);

674

/* EOF */

675

if(bytes_read == 0){

676

break;

677

}

678

/* check bytes_read for failure */

679

if(bytes_read < 0){

680

perror_plus("read");

681

free(params.data);

682

params.data = NULL;

683

dhparamsfilename = NULL;

684

break;

685

}

686

params.size += (unsigned int)bytes_read;

687

}

688

ret = close(dhpfile);

689

if(ret == -1){

690

perror_plus("close");

691

}

692

if(params.data == NULL){

693

dhparamsfilename = NULL;

694

}

695

if(dhparamsfilename == NULL){

696

break;

697

}

698

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

699

GNUTLS_X509_FMT_PEM);

700

if(ret != GNUTLS_E_SUCCESS){

701

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

702

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

703

safer_gnutls_strerror(ret));

704

dhparamsfilename = NULL;

705

}

706

free(params.data);

707

} while(false);

708

}

709

if(dhparamsfilename == NULL){

710

if(mc->dh_bits == 0){

711

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

712

/* Try to read the private key file */

713

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

714

do {

715

int secfile = open(seckeyfilename, O_RDONLY);

716

if(secfile == -1){

717

perror_plus("open");

718

break;

719

}

720

size_t buffer_capacity = 0;

721

while(true){

722

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

723

(size_t)buffer.size,

724

(size_t)buffer_capacity);

725

if(buffer_capacity == 0){

726

perror_plus("incbuffer");

727

free(buffer.data);

728

buffer.data = NULL;

729

break;

730

}

731

ssize_t bytes_read = read(secfile,

732

buffer.data + buffer.size,

733

BUFFER_SIZE);

734

/* EOF */

735

if(bytes_read == 0){

736

break;

737

}

738

/* check bytes_read for failure */

739

if(bytes_read < 0){

740

perror_plus("read");

741

free(buffer.data);

742

buffer.data = NULL;

743

break;

744

}

745

buffer.size += (unsigned int)bytes_read;

746

}

747

close(secfile);

748

} while(false);

749

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

750

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

751

if(buffer.data != NULL){

752

{

753

gnutls_openpgp_privkey_t privkey = NULL;

754

ret = gnutls_openpgp_privkey_init(&privkey);

755

if(ret != GNUTLS_E_SUCCESS){

756

fprintf_plus(stderr, "Error initializing OpenPGP key"

757

" structure: %s",

758

safer_gnutls_strerror(ret));

759

free(buffer.data);

760

buffer.data = NULL;

761

} else {

762

ret = gnutls_openpgp_privkey_import

763

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

764

if(ret != GNUTLS_E_SUCCESS){

765

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

766

safer_gnutls_strerror(ret));

767

privkey = NULL;

768

}

769

free(buffer.data);

770

buffer.data = NULL;

771

if(privkey != NULL){

772

/* Use private key to suggest an appropriate

773

sec_param */

774

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

775

gnutls_openpgp_privkey_deinit(privkey);

776

if(debug){

777

fprintf_plus(stderr, "This OpenPGP key implies using"

778

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

779

safe_string(gnutls_sec_param_get_name

780

(sec_param)));

781

}

782

}

783

}

784

}

785

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

786

/* Err on the side of caution */

787

sec_param = GNUTLS_SEC_PARAM_ULTRA;

788

if(debug){

789

fprintf_plus(stderr, "Falling back to security parameter"

790

" \"%s\"\n",

791

safe_string(gnutls_sec_param_get_name

792

(sec_param)));

793

}

794

}

795

}

796

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

797

if(uret != 0){

798

mc->dh_bits = uret;

799

if(debug){

800

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

801

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

802

safe_string(gnutls_sec_param_get_name

803

(sec_param)),

804

mc->dh_bits);

805

}

806

} else {

807

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

808

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

809

safe_string(gnutls_sec_param_get_name

810

(sec_param)),

811

safer_gnutls_strerror(ret));

812

goto globalfail;

813

}

814

} else if(debug){

815

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

816

mc->dh_bits);

817

}

818

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

819

if(ret != GNUTLS_E_SUCCESS){

820

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

821

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

822

safer_gnutls_strerror(ret));

823

goto globalfail;

824

}

825

}

826

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

470

827

471

828

return 0;

472

829

473

830

globalfail:

474

831

475

gnutls_certificate_free_credentials(mc.cred);

476

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

832

gnutls_certificate_free_credentials(mc->cred);

833

gnutls_dh_params_deinit(mc->dh_params);

478

834

return -1;

479

835

}

480

836

481

static int init_gnutls_session(gnutls_session_t *session){

837

__attribute__((nonnull, warn_unused_result))

838

static int init_gnutls_session(gnutls_session_t *session,

839

mandos_context *mc){

482

840

int ret;

483

841

/* GnuTLS session creation */

484

842

do {

488

846

}

489

847

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

490

848

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

849

fprintf_plus(stderr,

850

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

851

safer_gnutls_strerror(ret));

493

852

}

494

853

495

854

{

496

855

const char *err;

497

856

do {

498

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

857

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

499

858

if(quit_now){

500

859

gnutls_deinit(*session);

501

860

return -1;

502

861

}

503

862

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

504

863

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

864

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

865

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

866

safer_gnutls_strerror(ret));

508

867

gnutls_deinit(*session);

509

868

return -1;

510

869

}

512

871

513

872

do {

514

873

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

874

mc->cred);

516

875

if(quit_now){

517

876

gnutls_deinit(*session);

518

877

return -1;

519

878

}

520

879

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

521

880

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

881

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

882

safer_gnutls_strerror(ret));

524

883

gnutls_deinit(*session);

525

884

return -1;

526

885

}

528

887

/* ignore client certificate if any. */

529

888

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

889

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

532

533

890

return 0;

534

891

}

535

892

537

894

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

538

895

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

539

896

897

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

898

__attribute__((warn_unused_result))

899

int raise_privileges(void){

900

int old_errno = errno;

901

int ret = 0;

902

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

903

ret = errno;

904

}

905

errno = old_errno;

906

return ret;

907

}

908

909

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

910

__attribute__((warn_unused_result))

911

int raise_privileges_permanently(void){

912

int old_errno = errno;

913

int ret = raise_privileges();

914

if(ret != 0){

915

errno = old_errno;

916

return ret;

917

}

918

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

919

ret = errno;

920

}

921

errno = old_errno;

922

return ret;

923

}

924

925

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

926

__attribute__((warn_unused_result))

927

int lower_privileges(void){

928

int old_errno = errno;

929

int ret = 0;

930

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

931

ret = errno;

932

}

933

errno = old_errno;

934

return ret;

935

}

936

937

/* Lower privileges permanently */

938

__attribute__((warn_unused_result))

939

int lower_privileges_permanently(void){

940

int old_errno = errno;

941

int ret = 0;

942

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

943

ret = errno;

944

}

945

errno = old_errno;

946

return ret;

947

}

948

949

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

950

__attribute__((nonnull, warn_unused_result))

951

static bool add_delete_local_route(const bool add,

952

const char *address,

953

AvahiIfIndex if_index){

954

int ret;

955

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

956

char add_arg[] = "add";

957

char delete_arg[] = "delete";

958

char debug_flag[] = "--debug";

959

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

960

if(pluginhelperdir == NULL){

961

if(debug){

962

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

963

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

964

}

965

return false;

966

}

967

968

char interface[IF_NAMESIZE];

969

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

970

perror_plus("if_indextoname");

971

return false;

972

}

973

974

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

975

if(devnull == -1){

976

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

977

return false;

978

}

979

pid_t pid = fork();

980

if(pid == 0){

981

/* Child */

982

/* Raise privileges */

983

errno = raise_privileges_permanently();

984

if(errno != 0){

985

perror_plus("Failed to raise privileges");

986

/* _exit(EX_NOPERM); */

987

} else {

988

/* Set group */

989

errno = 0;

990

ret = setgid(0);

991

if(ret == -1){

992

perror_plus("setgid");

993

_exit(EX_NOPERM);

994

}

995

/* Reset supplementary groups */

996

errno = 0;

997

ret = setgroups(0, NULL);

998

if(ret == -1){

999

perror_plus("setgroups");

1000

_exit(EX_NOPERM);

1001

}

1002

}

1003

ret = dup2(devnull, STDIN_FILENO);

1004

if(ret == -1){

1005

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

1006

_exit(EX_OSERR);

1007

}

1008

ret = close(devnull);

1009

if(ret == -1){

1010

perror_plus("close");

1011

_exit(EX_OSERR);

1012

}

1013

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1014

if(ret == -1){

1015

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

1016

_exit(EX_OSERR);

1017

}

1018

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

1019

O_RDONLY

1020

| O_DIRECTORY

1021

| O_PATH

1022

| O_CLOEXEC));

1023

if(helperdir_fd == -1){

1024

perror_plus("open");

1025

_exit(EX_UNAVAILABLE);

1026

}

1027

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

1028

helper, O_RDONLY));

1029

if(helper_fd == -1){

1030

perror_plus("openat");

1031

close(helperdir_fd);

1032

_exit(EX_UNAVAILABLE);

1033

}

1034

close(helperdir_fd);

1035

#ifdef __GNUC__

1036

#pragma GCC diagnostic push

1037

#pragma GCC diagnostic ignored "-Wcast-qual"

1038

#endif

1039

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

1040

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

1041

interface, debug ? debug_flag : NULL, NULL },

1042

environ) == -1){

1043

#ifdef __GNUC__

1044

#pragma GCC diagnostic pop

1045

#endif

1046

perror_plus("fexecve");

1047

_exit(EXIT_FAILURE);

1048

}

1049

}

1050

if(pid == -1){

1051

perror_plus("fork");

1052

return false;

1053

}

1054

int status;

1055

pid_t pret = -1;

1056

errno = 0;

1057

do {

1058

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

1059

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

1060

int errno_raising = 0;

1061

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

1062

errno_raising = errno;

1063

perror_plus("Failed to raise privileges in order to"

1064

" kill helper program");

1065

}

1066

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

1067

perror_plus("kill");

1068

}

1069

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

1070

perror_plus("Failed to lower privileges after killing"

1071

" helper program");

1072

}

1073

return false;

1074

}

1075

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

1076

if(pret == -1){

1077

perror_plus("waitpid");

1078

return false;

1079

}

1080

if(WIFEXITED(status)){

1081

if(WEXITSTATUS(status) != 0){

1082

fprintf_plus(stderr, "Error: iprouteadddel exited"

1083

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

1084

return false;

1085

}

1086

return true;

1087

}

1088

if(WIFSIGNALED(status)){

1089

fprintf_plus(stderr, "Error: iprouteadddel died by"

1090

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

1091

return false;

1092

}

1093

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

1094

return false;

1095

}

1096

1097

__attribute__((nonnull, warn_unused_result))

1098

static bool add_local_route(const char *address,

1099

AvahiIfIndex if_index){

1100

if(debug){

1101

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

1102

}

1103

return add_delete_local_route(true, address, if_index);

1104

}

1105

1106

__attribute__((nonnull, warn_unused_result))

1107

static bool delete_local_route(const char *address,

1108

AvahiIfIndex if_index){

1109

if(debug){

1110

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

1111

}

1112

return add_delete_local_route(false, address, if_index);

1113

}

1114

540

1115

/* Called when a Mandos server is found */

541

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

1116

__attribute__((nonnull, warn_unused_result))

1117

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

542

1118

AvahiIfIndex if_index,

543

int af){

1119

int af, mandos_context *mc){

544

1120

int ret, tcp_sd = -1;

545

1121

ssize_t sret;

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

1122

struct sockaddr_storage to;

550

1123

char *buffer = NULL;

551

1124

char *decrypted_buffer = NULL;

552

1125

size_t buffer_length = 0;

555

1128

int retval = -1;

556

1129

gnutls_session_t session;

557

1130

int pf; /* Protocol family */

1131

bool route_added = false;

558

1132

559

1133

errno = 0;

560

1134

571

1145

pf = PF_INET;

572

1146

break;

573

1147

default:

574

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

1148

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

575

1149

errno = EINVAL;

576

1150

return -1;

577

1151

}

578

1152

579

ret = init_gnutls_session(&session);

1153

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

1154

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

1155

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

1156

bool match = false;

1157

{

1158

char *interface = NULL;

1159

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

1160

mc->interfaces_size,

1161

interface))){

1162

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

1163

match = true;

1164

break;

1165

}

1166

}

1167

}

1168

if(not match){

1169

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

1170

connect to the server */

1171

if(debug){

1172

char interface[IF_NAMESIZE];

1173

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

1174

perror_plus("if_indextoname");

1175

} else {

1176

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

1177

" \"%s\"\n",

1178

if_indextoname((unsigned int)if_index,

1179

interface));

1180

}

1181

}

1182

return -1;

1183

}

1184

}

1185

1186

ret = init_gnutls_session(&session, mc);

580

1187

if(ret != 0){

581

1188

return -1;

582

1189

}

583

1190

584

1191

if(debug){

585

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

586

"\n", ip, port);

1192

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

1193

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

587

1194

}

588

1195

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

1196

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

590

1197

if(tcp_sd < 0){

591

1198

int e = errno;

592

perror("socket");

1199

perror_plus("socket");

593

1200

errno = e;

594

1201

goto mandos_end;

595

1202

}

599

1206

goto mandos_end;

600

1207

}

601

1208

602

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

603

1209

if(af == AF_INET6){

604

to.in6.sin6_family = (sa_family_t)af;

605

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

1210

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

1211

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

1212

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

606

1213

} else { /* IPv4 */

607

to.in.sin_family = (sa_family_t)af;

608

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

1214

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

1215

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

1216

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

609

1217

}

610

1218

if(ret < 0 ){

611

1219

int e = errno;

612

perror("inet_pton");

1220

perror_plus("inet_pton");

613

1221

errno = e;

614

1222

goto mandos_end;

615

1223

}

616

1224

if(ret == 0){

617

1225

int e = errno;

618

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

1226

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

619

1227

errno = e;

620

1228

goto mandos_end;

621

1229

}

622

1230

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

1231

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

1232

if(IN6_IS_ADDR_LINKLOCAL

1233

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

630

1234

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

1235

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

1236

" incomplete without a network interface\n");

633

1237

errno = EINVAL;

634

1238

goto mandos_end;

635

1239

}

636

1240

/* Set the network interface number as scope */

637

to.in6.sin6_scope_id = (uint32_t)if_index;

1241

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

638

1242

}

639

1243

} else {

640

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

641

-Wconversion and

642

-Wunreachable-code */

1244

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

643

1245

}

644

1246

645

1247

if(quit_now){

651

1253

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

652

1254

char interface[IF_NAMESIZE];

653

1255

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

654

perror("if_indextoname");

1256

perror_plus("if_indextoname");

655

1257

} else {

656

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

657

ip, interface, port);

1258

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

1259

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

658

1260

}

659

1261

} else {

660

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

661

port);

1262

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

1263

ip, (uintmax_t)port);

662

1264

}

663

1265

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

1266

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

665

const char *pcret;

666

if(af == AF_INET6){

667

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

668

sizeof(addrstr));

669

} else {

670

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

671

sizeof(addrstr));

672

}

673

if(pcret == NULL){

674

perror("inet_ntop");

675

} else {

676

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

677

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

678

}

679

}

680

}

681

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

687

if(af == AF_INET6){

688

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

689

} else {

690

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

691

}

692

if(ret < 0){

693

int e = errno;

694

perror("connect");

695

errno = e;

696

goto mandos_end;

697

}

698

699

if(quit_now){

700

errno = EINTR;

701

goto mandos_end;

1267

if(af == AF_INET6){

1268

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

1269

sizeof(struct sockaddr_in6),

1270

addrstr, sizeof(addrstr), NULL, 0,

1271

NI_NUMERICHOST);

1272

} else {

1273

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

1274

sizeof(struct sockaddr_in),

1275

addrstr, sizeof(addrstr), NULL, 0,

1276

NI_NUMERICHOST);

1277

}

1278

if(ret == EAI_SYSTEM){

1279

perror_plus("getnameinfo");

1280

} else if(ret != 0) {

1281

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

1282

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

1283

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

1284

}

1285

}

1286

1287

if(quit_now){

1288

errno = EINTR;

1289

goto mandos_end;

1290

}

1291

1292

while(true){

1293

if(af == AF_INET6){

1294

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

1295

sizeof(struct sockaddr_in6));

1296

} else {

1297

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

1298

sizeof(struct sockaddr_in));

1299

}

1300

if(ret < 0){

1301

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

1302

and if_index != AVAHI_IF_UNSPEC

1303

and connect_to == NULL

1304

and not route_added and

1305

((af == AF_INET6 and not

1306

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1307

&to)->sin6_addr)))

1308

or (af == AF_INET and

1309

/* Not a a IPv4LL address */

1310

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

1311

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

1312

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

1313

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

1314

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

1315

connect to a Mandos server announced by Avahi on a server

1316

host with a global address. Work around this by retrying

1317

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

1318

1319

Avahi bug reference:

1320

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

1321

https://bugs.debian.org/587961

1322

*/

1323

if(debug){

1324

fprintf_plus(stderr, "Mandos server unreachable, trying"

1325

" direct route\n");

1326

}

1327

int e = errno;

1328

route_added = add_local_route(ip, if_index);

1329

if(route_added){

1330

continue;

1331

}

1332

errno = e;

1333

}

1334

if(errno != ECONNREFUSED or debug){

1335

int e = errno;

1336

perror_plus("connect");

1337

errno = e;

1338

}

1339

goto mandos_end;

1340

}

1341

1342

if(quit_now){

1343

errno = EINTR;

1344

goto mandos_end;

1345

}

1346

break;

702

1347

}

703

1348

704

1349

const char *out = mandos_protocol_version;

706

1351

while(true){

707

1352

size_t out_size = strlen(out);

708

1353

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

709

out_size - written));

1354

out_size - written));

710

1355

if(ret == -1){

711

1356

int e = errno;

712

perror("write");

1357

perror_plus("write");

713

1358

errno = e;

714

1359

goto mandos_end;

715

1360

}

732

1377

}

733

1378

734

1379

if(debug){

735

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

1380

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

736

1381

}

737

1382

738

1383

if(quit_now){

740

1385

goto mandos_end;

741

1386

}

742

1387

743

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1388

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

1389

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

1390

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

1391

gnutls_transport_set_ptr(session,

1392

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

744

1393

745

1394

if(quit_now){

746

1395

errno = EINTR;

757

1406

758

1407

if(ret != GNUTLS_E_SUCCESS){

759

1408

if(debug){

760

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

1409

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

761

1410

gnutls_perror(ret);

762

1411

}

763

1412

errno = EPROTO;

767

1416

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

768

1417

769

1418

if(debug){

770

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

771

ip);

1419

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1420

" %s\n", ip);

772

1421

}

773

1422

774

1423

while(true){

779

1428

}

780

1429

781

1430

buffer_capacity = incbuffer(&buffer, buffer_length,

782

buffer_capacity);

1431

buffer_capacity);

783

1432

if(buffer_capacity == 0){

784

1433

int e = errno;

785

perror("incbuffer");

1434

perror_plus("incbuffer");

786

1435

errno = e;

787

1436

goto mandos_end;

788

1437

}

812

1461

}

813

1462

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

814

1463

if(ret < 0){

815

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

1464

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

1465

"***\n");

816

1466

gnutls_perror(ret);

817

1467

errno = EPROTO;

818

1468

goto mandos_end;

819

1469

}

820

1470

break;

821

1471

default:

822

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

823

" encrypted session with Mandos server\n");

1472

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

1473

" encrypted session with Mandos server\n");

824

1474

gnutls_bye(session, GNUTLS_SHUT_RDWR);

825

1475

errno = EIO;

826

1476

goto mandos_end;

831

1481

}

832

1482

833

1483

if(debug){

834

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

1484

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

835

1485

}

836

1486

837

1487

if(quit_now){

849

1499

850

1500

if(buffer_length > 0){

851

1501

ssize_t decrypted_buffer_size;

852

decrypted_buffer_size = pgp_packet_decrypt(buffer,

853

buffer_length,

854

&decrypted_buffer);

1502

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1503

&decrypted_buffer, mc);

855

1504

if(decrypted_buffer_size >= 0){

856

1505

1506

clearerr(stdout);

857

1507

written = 0;

858

1508

while(written < (size_t) decrypted_buffer_size){

859

1509

if(quit_now){

867

1517

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

868

1518

int e = errno;

869

1519

if(debug){

870

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

871

strerror(errno));

1520

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

1521

strerror(errno));

872

1522

}

873

1523

errno = e;

874

1524

goto mandos_end;

875

1525

}

876

1526

written += (size_t)ret;

877

1527

}

1528

ret = fflush(stdout);

1529

if(ret != 0){

1530

int e = errno;

1531

if(debug){

1532

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

1533

strerror(errno));

1534

}

1535

errno = e;

1536

goto mandos_end;

1537

}

878

1538

retval = 0;

879

1539

}

880

1540

}

883

1543

884

1544

mandos_end:

885

1545

{

1546

if(route_added){

1547

if(not delete_local_route(ip, if_index)){

1548

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

1549

" interface %d", ip, if_index);

1550

}

1551

}

886

1552

int e = errno;

887

1553

free(decrypted_buffer);

888

1554

free(buffer);

889

1555

if(tcp_sd >= 0){

890

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

1556

ret = close(tcp_sd);

891

1557

}

892

1558

if(ret == -1){

893

1559

if(e == 0){

894

1560

e = errno;

895

1561

}

896

perror("close");

1562

perror_plus("close");

897

1563

}

898

1564

gnutls_deinit(session);

1565

errno = e;

899

1566

if(quit_now){

900

e = EINTR;

1567

errno = EINTR;

901

1568

retval = -1;

902

1569

}

903

errno = e;

904

1570

}

905

1571

return retval;

906

1572

}

918

1584

AVAHI_GCC_UNUSED AvahiStringList *txt,

919

1585

AVAHI_GCC_UNUSED AvahiLookupResultFlags

920

1586

flags,

921

AVAHI_GCC_UNUSED void* userdata){

922

assert(r);

1587

void *mc){

1588

if(r == NULL){

1589

return;

1590

}

923

1591

924

1592

/* Called whenever a service has been resolved successfully or

925

1593

timed out */

926

1594

927

1595

if(quit_now){

1596

avahi_s_service_resolver_free(r);

928

1597

return;

929

1598

}

930

1599

931

1600

switch(event){

932

1601

default:

933

1602

case AVAHI_RESOLVER_FAILURE:

934

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

935

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

936

avahi_strerror(avahi_server_errno(mc.server)));

1603

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

1604

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

1605

domain,

1606

avahi_strerror(avahi_server_errno

1607

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

937

1608

break;

938

1609

939

1610

case AVAHI_RESOLVER_FOUND:

941

1612

char ip[AVAHI_ADDRESS_STR_MAX];

942

1613

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

943

1614

if(debug){

944

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

945

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

946

ip, (intmax_t)interface, port);

1615

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

1616

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

1617

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

947

1618

}

948

int ret = start_mandos_communication(ip, port, interface,

949

avahi_proto_to_af(proto));

1619

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

1620

interface,

1621

avahi_proto_to_af(proto),

1622

mc);

950

1623

if(ret == 0){

951

avahi_simple_poll_quit(mc.simple_poll);

1624

avahi_simple_poll_quit(simple_poll);

1625

} else {

1626

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

1627

avahi_proto_to_af(proto),

1628

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

1629

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

1630

" list\n", name);

1631

}

952

1632

}

953

1633

}

954

1634

}

964

1644

const char *domain,

965

1645

AVAHI_GCC_UNUSED AvahiLookupResultFlags

966

1646

flags,

967

AVAHI_GCC_UNUSED void* userdata){

968

assert(b);

1647

void *mc){

1648

if(b == NULL){

1649

return;

1650

}

969

1651

970

1652

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

971

1653

is removed from the LAN */

978

1660

default:

979

1661

case AVAHI_BROWSER_FAILURE:

980

1662

981

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

982

avahi_strerror(avahi_server_errno(mc.server)));

983

avahi_simple_poll_quit(mc.simple_poll);

1663

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

1664

avahi_strerror(avahi_server_errno

1665

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

1666

avahi_simple_poll_quit(simple_poll);

984

1667

return;

985

1668

986

1669

case AVAHI_BROWSER_NEW:

989

1672

the callback function is called the Avahi server will free the

990

1673

resolver for us. */

991

1674

992

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

993

name, type, domain, protocol, 0,

994

resolve_callback, NULL) == NULL)

995

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

996

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

1675

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

1676

interface, protocol, name, type,

1677

domain, protocol, 0,

1678

resolve_callback, mc) == NULL)

1679

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

1680

" %s\n", name,

1681

avahi_strerror(avahi_server_errno

1682

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

997

1683

break;

998

1684

999

1685

case AVAHI_BROWSER_REMOVE:

1002

1688

case AVAHI_BROWSER_ALL_FOR_NOW:

1003

1689

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1004

1690

if(debug){

1005

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

1691

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

1692

" searching...\n");

1006

1693

}

1007

1694

break;

1008

1695

}

1009

1696

}

1010

1697

1011

/* stop main loop after sigterm has been called */

1698

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

1012

1699

static void handle_sigterm(int sig){

1013

1700

if(quit_now){

1014

1701

return;

1016

1703

quit_now = 1;

1017

1704

signal_received = sig;

1018

1705

int old_errno = errno;

1019

if(mc.simple_poll != NULL){

1020

avahi_simple_poll_quit(mc.simple_poll);

1706

/* set main loop to exit */

1707

if(simple_poll != NULL){

1708

avahi_simple_poll_quit(simple_poll);

1021

1709

}

1022

1710

errno = old_errno;

1023

1711

}

1024

1712

1713

__attribute__((nonnull, warn_unused_result))

1714

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

1715

int ret;

1716

int old_errno;

1717

1718

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

1719

if(s < 0){

1720

old_errno = errno;

1721

perror_plus("socket");

1722

errno = old_errno;

1723

return false;

1724

}

1725

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

1726

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

1727

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1728

if(ret == -1){

1729

if(debug){

1730

old_errno = errno;

1731

perror_plus("ioctl SIOCGIFFLAGS");

1732

errno = old_errno;

1733

}

1734

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

1735

old_errno = errno;

1736

perror_plus("close");

1737

errno = old_errno;

1738

}

1739

return false;

1740

}

1741

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

1742

old_errno = errno;

1743

perror_plus("close");

1744

errno = old_errno;

1745

}

1746

return true;

1747

}

1748

1749

__attribute__((nonnull, warn_unused_result))

1750

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

1751

1752

/* Reject the loopback device */

1753

if(ifr->ifr_flags & IFF_LOOPBACK){

1754

if(debug){

1755

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

1756

ifname);

1757

}

1758

return false;

1759

}

1760

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

1761

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

1762

if(debug){

1763

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

1764

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

1765

}

1766

return true;

1767

}

1768

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

1769

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

1770

if(debug){

1771

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1772

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

1773

}

1774

return false;

1775

}

1776

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

1777

if(ifr->ifr_flags & IFF_NOARP){

1778

if(debug){

1779

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

1780

ifname);

1781

}

1782

return false;

1783

}

1784

1785

/* Accept this device */

1786

if(debug){

1787

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

1788

}

1789

return true;

1790

}

1791

1025

1792

/*

1026

1793

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

1027

1794

* corresponds to an acceptable network device.

1028

1795

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

1029

1796

*/

1797

__attribute__((nonnull, warn_unused_result))

1030

1798

int good_interface(const struct dirent *if_entry){

1031

ssize_t ssret;

1032

char *flagname = NULL;

1033

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

1034

if_entry->d_name);

1035

if(ret < 0){

1036

perror("asprintf");

1037

return 0;

1038

}

1039

1799

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

1040

1800

return 0;

1041

1801

}

1042

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

1043

if(flags_fd == -1){

1044

perror("open");

1045

return 0;

1046

}

1047

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

1048

/* read line from flags_fd */

1049

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

1050

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

1051

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

1052

if(flagstring == NULL){

1053

perror("malloc");

1054

close(flags_fd);

1055

return 0;

1056

}

1057

while(to_read > 0){

1058

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

1059

(size_t)to_read));

1060

if(ssret == -1){

1061

perror("read");

1062

free(flagstring);

1063

close(flags_fd);

1064

return 0;

1065

}

1066

to_read -= ssret;

1067

if(ssret == 0){

1802

1803

struct ifreq ifr;

1804

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

1805

if(debug){

1806

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

1807

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

1808

}

1809

return 0;

1810

}

1811

1812

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

1813

return 0;

1814

}

1815

return 1;

1816

}

1817

1818

/*

1819

* This function determines if a network interface is up.

1820

*/

1821

__attribute__((nonnull, warn_unused_result))

1822

bool interface_is_up(const char *interface){

1823

struct ifreq ifr;

1824

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

1825

if(debug){

1826

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

1827

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

1828

}

1829

return false;

1830

}

1831

1832

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

1833

}

1834

1835

/*

1836

* This function determines if a network interface is running

1837

*/

1838

__attribute__((nonnull, warn_unused_result))

1839

bool interface_is_running(const char *interface){

1840

struct ifreq ifr;

1841

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

1842

if(debug){

1843

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

1844

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

1845

}

1846

return false;

1847

}

1848

1849

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

1850

}

1851

1852

__attribute__((nonnull, pure, warn_unused_result))

1853

int notdotentries(const struct dirent *direntry){

1854

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

1855

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

1856

and (direntry->d_name[1] == '\0'

1857

or (direntry->d_name[1] == '.'

1858

and direntry->d_name[2] == '\0'))){

1859

return 0;

1860

}

1861

return 1;

1862

}

1863

1864

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

1865

__attribute__((nonnull, warn_unused_result))

1866

int runnable_hook(const struct dirent *direntry){

1867

int ret;

1868

size_t sret;

1869

struct stat st;

1870

1871

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

1872

/* Empty name? */

1873

return 0;

1874

}

1875

1876

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

1877

"abcdefghijklmnopqrstuvwxyz"

1878

"0123456789"

1879

"_.-");

1880

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

1881

/* Contains non-allowed characters */

1882

if(debug){

1883

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

1884

direntry->d_name);

1885

}

1886

return 0;

1887

}

1888

1889

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

1890

if(ret == -1){

1891

if(debug){

1892

perror_plus("Could not stat hook");

1893

}

1894

return 0;

1895

}

1896

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

1897

/* Not a regular file */

1898

if(debug){

1899

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

1900

direntry->d_name);

1901

}

1902

return 0;

1903

}

1904

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

1905

/* Not executable */

1906

if(debug){

1907

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

1908

direntry->d_name);

1909

}

1910

return 0;

1911

}

1912

if(debug){

1913

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

1914

direntry->d_name);

1915

}

1916

return 1;

1917

}

1918

1919

__attribute__((nonnull, warn_unused_result))

1920

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1921

mandos_context *mc){

1922

int ret;

1923

struct timespec now;

1924

struct timespec waited_time;

1925

intmax_t block_time;

1926

1927

while(true){

1928

if(mc->current_server == NULL){

1929

if(debug){

1930

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

1931

" No timeout!\n");

1932

}

1933

ret = avahi_simple_poll_iterate(s, -1);

1934

} else {

1935

if(debug){

1936

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

1937

" it, or wait\n");

1938

}

1939

/* the current time */

1940

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1941

if(ret == -1){

1942

perror_plus("clock_gettime");

1943

return -1;

1944

}

1945

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

1946

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

1947

waited_time.tv_sec = (now.tv_sec

1948

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

1949

waited_time.tv_nsec = (now.tv_nsec

1950

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

1951

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

1952

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

1953

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

1954

block_time = ((retry_interval

1955

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

1956

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

1957

1958

if(debug){

1959

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

1960

block_time);

1961

}

1962

1963

if(block_time <= 0){

1964

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

1965

mc->current_server->port,

1966

mc->current_server->if_index,

1967

mc->current_server->af, mc);

1968

if(ret == 0){

1969

avahi_simple_poll_quit(s);

1970

return 0;

1971

}

1972

ret = clock_gettime(CLOCK_MONOTONIC,

1973

&mc->current_server->last_seen);

1974

if(ret == -1){

1975

perror_plus("clock_gettime");

1976

return -1;

1977

}

1978

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

1979

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

1980

servers, but don't block */

1981

}

1982

1983

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

1984

}

1985

if(ret != 0){

1986

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

1987

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

1988

}

1989

}

1990

}

1991

}

1992

1993

__attribute__((nonnull))

1994

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

1995

const float delay){

1996

struct dirent **direntries = NULL;

1997

if(hookdir_fd == -1){

1998

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1999

| O_CLOEXEC);

2000

if(hookdir_fd == -1){

2001

if(errno == ENOENT){

2002

if(debug){

2003

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

2004

" found\n", hookdir);

2005

}

2006

} else {

2007

perror_plus("open");

2008

}

2009

return;

2010

}

2011

}

2012

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

2013

if(devnull == -1){

2014

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

2015

return;

2016

}

2017

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

2018

runnable_hook, alphasort);

2019

if(numhooks == -1){

2020

perror_plus("scandir");

2021

close(devnull);

2022

return;

2023

}

2024

struct dirent *direntry;

2025

int ret;

2026

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

2027

direntry = direntries[i];

2028

if(debug){

2029

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

2030

direntry->d_name);

2031

}

2032

pid_t hook_pid = fork();

2033

if(hook_pid == 0){

2034

/* Child */

2035

/* Raise privileges */

2036

errno = raise_privileges_permanently();

2037

if(errno != 0){

2038

perror_plus("Failed to raise privileges");

2039

_exit(EX_NOPERM);

2040

}

2041

/* Set group */

2042

errno = 0;

2043

ret = setgid(0);

2044

if(ret == -1){

2045

perror_plus("setgid");

2046

_exit(EX_NOPERM);

2047

}

2048

/* Reset supplementary groups */

2049

errno = 0;

2050

ret = setgroups(0, NULL);

2051

if(ret == -1){

2052

perror_plus("setgroups");

2053

_exit(EX_NOPERM);

2054

}

2055

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

2056

if(ret == -1){

2057

perror_plus("setenv");

2058

_exit(EX_OSERR);

2059

}

2060

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

2061

if(ret == -1){

2062

perror_plus("setenv");

2063

_exit(EX_OSERR);

2064

}

2065

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

2066

if(ret == -1){

2067

perror_plus("setenv");

2068

_exit(EX_OSERR);

2069

}

2070

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

2071

if(ret == -1){

2072

perror_plus("setenv");

2073

_exit(EX_OSERR);

2074

}

2075

char *delaystring;

2076

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

2077

if(ret == -1){

2078

perror_plus("asprintf");

2079

_exit(EX_OSERR);

2080

}

2081

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

2082

if(ret == -1){

2083

free(delaystring);

2084

perror_plus("setenv");

2085

_exit(EX_OSERR);

2086

}

2087

free(delaystring);

2088

if(connect_to != NULL){

2089

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

2090

if(ret == -1){

2091

perror_plus("setenv");

2092

_exit(EX_OSERR);

2093

}

2094

}

2095

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

2096

direntry->d_name,

2097

O_RDONLY));

2098

if(hook_fd == -1){

2099

perror_plus("openat");

2100

_exit(EXIT_FAILURE);

2101

}

2102

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

2103

perror_plus("close");

2104

_exit(EXIT_FAILURE);

2105

}

2106

ret = dup2(devnull, STDIN_FILENO);

2107

if(ret == -1){

2108

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

2109

_exit(EX_OSERR);

2110

}

2111

ret = close(devnull);

2112

if(ret == -1){

2113

perror_plus("close");

2114

_exit(EX_OSERR);

2115

}

2116

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2117

if(ret == -1){

2118

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

2119

_exit(EX_OSERR);

2120

}

2121

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

2122

environ) == -1){

2123

perror_plus("fexecve");

2124

_exit(EXIT_FAILURE);

2125

}

2126

} else {

2127

if(hook_pid == -1){

2128

perror_plus("fork");

2129

free(direntry);

2130

continue;

2131

}

2132

int status;

2133

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

2134

perror_plus("waitpid");

2135

free(direntry);

2136

continue;

2137

}

2138

if(WIFEXITED(status)){

2139

if(WEXITSTATUS(status) != 0){

2140

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

2141

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

2142

WEXITSTATUS(status));

2143

free(direntry);

2144

continue;

2145

}

2146

} else if(WIFSIGNALED(status)){

2147

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

2148

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

2149

WTERMSIG(status));

2150

free(direntry);

2151

continue;

2152

} else {

2153

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

2154

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

2155

free(direntry);

2156

continue;

2157

}

2158

}

2159

if(debug){

2160

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

2161

direntry->d_name);

2162

}

2163

free(direntry);

2164

}

2165

free(direntries);

2166

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

2167

perror_plus("close");

2168

} else {

2169

hookdir_fd = -1;

2170

}

2171

close(devnull);

2172

}

2173

2174

__attribute__((nonnull, warn_unused_result))

2175

int bring_up_interface(const char *const interface,

2176

const float delay){

2177

int old_errno = errno;

2178

int ret;

2179

struct ifreq network;

2180

unsigned int if_index = if_nametoindex(interface);

2181

if(if_index == 0){

2182

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

2183

errno = old_errno;

2184

return ENXIO;

2185

}

2186

2187

if(quit_now){

2188

errno = old_errno;

2189

return EINTR;

2190

}

2191

2192

if(not interface_is_up(interface)){

2193

int ret_errno = 0;

2194

int ioctl_errno = 0;

2195

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

2196

ret_errno = errno;

2197

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

2198

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

2199

errno = old_errno;

2200

return ret_errno;

2201

}

2202

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

2203

2204

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

2205

if(sd == -1){

2206

ret_errno = errno;

2207

perror_plus("socket");

2208

errno = old_errno;

2209

return ret_errno;

2210

}

2211

2212

if(quit_now){

2213

ret = close(sd);

2214

if(ret == -1){

2215

perror_plus("close");

2216

}

2217

errno = old_errno;

2218

return EINTR;

2219

}

2220

2221

if(debug){

2222

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

2223

interface);

2224

}

2225

2226

/* Raise privileges */

2227

ret_errno = raise_privileges();

2228

if(ret_errno != 0){

2229

errno = ret_errno;

2230

perror_plus("Failed to raise privileges");

2231

}

2232

2233

#ifdef __linux__

2234

int ret_linux;

2235

bool restore_loglevel = false;

2236

if(ret_errno == 0){

2237

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2238

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

2239

ret_linux = klogctl(8, NULL, 5);

2240

if(ret_linux == -1){

2241

perror_plus("klogctl");

2242

} else {

2243

restore_loglevel = true;

2244

}

2245

}

2246

#endif /* __linux__ */

2247

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

2248

ioctl_errno = errno;

2249

#ifdef __linux__

2250

if(restore_loglevel){

2251

ret_linux = klogctl(7, NULL, 0);

2252

if(ret_linux == -1){

2253

perror_plus("klogctl");

2254

}

2255

}

2256

#endif /* __linux__ */

2257

2258

/* If raise_privileges() succeeded above */

2259

if(ret_errno == 0){

2260

/* Lower privileges */

2261

ret_errno = lower_privileges();

2262

if(ret_errno != 0){

2263

errno = ret_errno;

2264

perror_plus("Failed to lower privileges");

2265

}

2266

}

2267

2268

/* Close the socket */

2269

ret = close(sd);

2270

if(ret == -1){

2271

perror_plus("close");

2272

}

2273

2274

if(ret_setflags == -1){

2275

errno = ioctl_errno;

2276

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2277

errno = old_errno;

2278

return ioctl_errno;

2279

}

2280

} else if(debug){

2281

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

2282

interface);

2283

}

2284

2285

/* Sleep checking until interface is running.

2286

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

2287

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

2288

if(interface_is_running(interface)){

1068

2289

break;

1069

2290

}

1070

}

1071

close(flags_fd);

1072

intmax_t tmpmax;

1073

char *tmp;

1074

errno = 0;

1075

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

1076

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

1077

and not (isspace(*tmp)))

1078

or tmpmax != (ifreq_flags)tmpmax){

1079

if(debug){

1080

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

1081

flagstring, if_entry->d_name);

1082

}

1083

free(flagstring);

1084

return 0;

1085

}

1086

free(flagstring);

1087

ifreq_flags flags = (ifreq_flags)tmpmax;

1088

/* Reject the loopback device */

1089

if(flags & IFF_LOOPBACK){

1090

if(debug){

1091

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

1092

if_entry->d_name);

1093

}

1094

return 0;

1095

}

1096

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

1097

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

1098

if(debug){

1099

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

1100

if_entry->d_name);

1101

}

1102

return 1;

1103

}

1104

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

1105

if(not (flags & IFF_BROADCAST)){

1106

if(debug){

1107

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

1108

if_entry->d_name);

1109

}

1110

return 0;

1111

}

1112

/* Accept this device */

1113

if(debug){

1114

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

1115

if_entry->d_name);

1116

}

1117

return 1;

2291

struct timespec sleeptime = { .tv_nsec = 250000000 };

2292

ret = nanosleep(&sleeptime, NULL);

2293

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

2294

perror_plus("nanosleep");

2295

}

2296

}

2297

2298

errno = old_errno;

2299

return 0;

2300

}

2301

2302

__attribute__((nonnull, warn_unused_result))

2303

int take_down_interface(const char *const interface){

2304

int old_errno = errno;

2305

struct ifreq network;

2306

unsigned int if_index = if_nametoindex(interface);

2307

if(if_index == 0){

2308

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

2309

errno = old_errno;

2310

return ENXIO;

2311

}

2312

if(interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

2316

ret_errno = errno;

2317

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

2318

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

2319

errno = old_errno;

2320

return ret_errno;

2321

}

2322

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

2323

2324

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

2325

if(sd == -1){

2326

ret_errno = errno;

2327

perror_plus("socket");

2328

errno = old_errno;

2329

return ret_errno;

2330

}

2331

2332

if(debug){

2333

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

2334

interface);

2335

}

2336

2337

/* Raise privileges */

2338

ret_errno = raise_privileges();

2339

if(ret_errno != 0){

2340

errno = ret_errno;

2341

perror_plus("Failed to raise privileges");

2342

}

2343

2344

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

2345

ioctl_errno = errno;

2346

2347

/* If raise_privileges() succeeded above */

2348

if(ret_errno == 0){

2349

/* Lower privileges */

2350

ret_errno = lower_privileges();

2351

if(ret_errno != 0){

2352

errno = ret_errno;

2353

perror_plus("Failed to lower privileges");

2354

}

2355

}

2356

2357

/* Close the socket */

2358

int ret = close(sd);

2359

if(ret == -1){

2360

perror_plus("close");

2361

}

2362

2363

if(ret_setflags == -1){

2364

errno = ioctl_errno;

2365

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2366

errno = old_errno;

2367

return ioctl_errno;

2368

}

2369

} else if(debug){

2370

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

2371

interface);

2372

}

2373

2374

errno = old_errno;

2375

return 0;

1118

2376

}

1119

2377

1120

2378

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

2379

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

2380

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

2381

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

2382

.current_server = NULL, .interfaces = NULL,

2383

.interfaces_size = 0 };

1121

2384

AvahiSServiceBrowser *sb = NULL;

1122

int error;

2385

error_t ret_errno;

1123

2386

int ret;

1124

2387

intmax_t tmpmax;

1125

2388

char *tmp;

1126

2389

int exitcode = EXIT_SUCCESS;

1127

const char *interface = "";

1128

struct ifreq network;

1129

int sd = -1;

1130

bool take_down_interface = false;

1131

uid_t uid;

1132

gid_t gid;

1133

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

1134

bool tempdir_created = false;

2390

char *interfaces_to_take_down = NULL;

2391

size_t interfaces_to_take_down_size = 0;

2392

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

2393

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

2394

char *tempdir = NULL;

1135

2395

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1136

2396

const char *seckey = PATHDIR "/" SECKEY;

1137

2397

const char *pubkey = PATHDIR "/" PUBKEY;

2398

const char *dh_params_file = NULL;

2399

char *interfaces_hooks = NULL;

1138

2400

1139

2401

bool gnutls_initialized = false;

1140

2402

bool gpgme_initialized = false;

1141

2403

float delay = 2.5f;

2404

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

2405

retrying the same server again */

1142

2406

1143

2407

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1144

2408

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1150

2414

errno = 0;

1151

2415

ret = setgid(gid);

1152

2416

if(ret == -1){

1153

perror("setgid");

2417

perror_plus("setgid");

1154

2418

}

1155

2419

1156

2420

/* Lower user privileges (temporarily) */

1157

2421

errno = 0;

1158

2422

ret = seteuid(uid);

1159

2423

if(ret == -1){

1160

perror("seteuid");

2424

perror_plus("seteuid");

1161

2425

}

1162

2426

1163

2427

if(quit_now){

1190

2454

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

1191

2455

" Diffie-Hellman key exchange",

1192

2456

.group = 2 },

2457

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

2458

.arg = "FILE",

2459

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

2460

" for the Diffie-Hellman key exchange",

2461

.group = 2 },

1193

2462

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

1194

2463

.arg = "STRING",

1195

2464

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

1198

2467

.arg = "SECONDS",

1199

2468

.doc = "Maximum delay to wait for interface startup",

1200

2469

.group = 2 },

2470

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

2471

.arg = "SECONDS",

2472

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

2473

.group = 2 },

2474

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

2475

.arg = "DIR",

2476

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

2477

.group = 2 },

1201

2478

/*

1202

2479

* These reproduce what we would get without ARGP_NO_HELP

1203

2480

*/

1221

2498

connect_to = arg;

1222

2499

break;

1223

2500

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

1224

interface = arg;

2501

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

2502

arg, (int)',');

2503

if(ret_errno != 0){

2504

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

2505

}

1225

2506

break;

1226

2507

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

1227

2508

seckey = arg;

1238

2519

}

1239

2520

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

1240

2521

break;

2522

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

2523

dh_params_file = arg;

2524

break;

1241

2525

case 130: /* --priority */

1242

2526

mc.priority = arg;

1243

2527

break;

1247

2531

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

1248

2532

argp_error(state, "Bad delay");

1249

2533

}

2534

case 132: /* --retry */

2535

errno = 0;

2536

retry_interval = strtod(arg, &tmp);

2537

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

2538

or (retry_interval * 1000) > INT_MAX

2539

or retry_interval < 0){

2540

argp_error(state, "Bad retry interval");

2541

}

2542

break;

2543

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

2544

hookdir = arg;

1250

2545

break;

1251

2546

/*

1252

2547

* These reproduce what we would get without ARGP_NO_HELP

1259

2554

argp_state_help(state, state->out_stream,

1260

2555

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1261

2556

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

1262

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

2557

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

1263

2558

exit(argp_err_exit_status);

1264

2559

break;

1265

2560

default:

1272

2567

.args_doc = "",

1273

2568

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

1274

2569

" passwords from a Mandos server" };

1275

ret = argp_parse(&argp, argc, argv,

1276

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1277

switch(ret){

2570

ret_errno = argp_parse(&argp, argc, argv,

2571

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2572

switch(ret_errno){

1278

2573

case 0:

1279

2574

break;

1280

2575

case ENOMEM:

1281

2576

default:

1282

errno = ret;

1283

perror("argp_parse");

2577

errno = ret_errno;

2578

perror_plus("argp_parse");

1284

2579

exitcode = EX_OSERR;

1285

2580

goto end;

1286

2581

case EINVAL:

1289

2584

}

1290

2585

}

1291

2586

2587

{

2588

/* Work around Debian bug #633582:

2589

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

2590

2591

/* Re-raise privileges */

2592

ret = raise_privileges();

2593

if(ret != 0){

2594

errno = ret;

2595

perror_plus("Failed to raise privileges");

2596

} else {

2597

struct stat st;

2598

2599

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

2600

int seckey_fd = open(seckey, O_RDONLY);

2601

if(seckey_fd == -1){

2602

perror_plus("open");

2603

} else {

2604

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

2605

if(ret == -1){

2606

perror_plus("fstat");

2607

} else {

2608

if(S_ISREG(st.st_mode)

2609

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

2610

ret = fchown(seckey_fd, uid, gid);

2611

if(ret == -1){

2612

perror_plus("fchown");

2613

}

2614

}

2615

}

2616

close(seckey_fd);

2617

}

2618

}

2619

2620

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

2621

int pubkey_fd = open(pubkey, O_RDONLY);

2622

if(pubkey_fd == -1){

2623

perror_plus("open");

2624

} else {

2625

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

2626

if(ret == -1){

2627

perror_plus("fstat");

2628

} else {

2629

if(S_ISREG(st.st_mode)

2630

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

2631

ret = fchown(pubkey_fd, uid, gid);

2632

if(ret == -1){

2633

perror_plus("fchown");

2634

}

2635

}

2636

}

2637

close(pubkey_fd);

2638

}

2639

}

2640

2641

if(dh_params_file != NULL

2642

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

2643

int dhparams_fd = open(dh_params_file, O_RDONLY);

2644

if(dhparams_fd == -1){

2645

perror_plus("open");

2646

} else {

2647

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

2648

if(ret == -1){

2649

perror_plus("fstat");

2650

} else {

2651

if(S_ISREG(st.st_mode)

2652

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

2653

ret = fchown(dhparams_fd, uid, gid);

2654

if(ret == -1){

2655

perror_plus("fchown");

2656

}

2657

}

2658

}

2659

close(dhparams_fd);

2660

}

2661

}

2662

2663

/* Lower privileges */

2664

ret = lower_privileges();

2665

if(ret != 0){

2666

errno = ret;

2667

perror_plus("Failed to lower privileges");

2668

}

2669

}

2670

}

2671

2672

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

2673

{

2674

char *interface = NULL;

2675

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

2676

interface))){

2677

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

2678

and if_nametoindex(interface) == 0){

2679

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

2680

fprintf_plus(stderr, "Not using nonexisting interface"

2681

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

2682

}

2683

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

2684

interface = NULL;

2685

}

2686

}

2687

}

2688

2689

/* Run network hooks */

2690

{

2691

if(mc.interfaces != NULL){

2692

interfaces_hooks = malloc(mc.interfaces_size);

2693

if(interfaces_hooks == NULL){

2694

perror_plus("malloc");

2695

goto end;

2696

}

2697

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

2698

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

2699

}

2700

run_network_hooks("start", interfaces_hooks != NULL ?

2701

interfaces_hooks : "", delay);

2702

}

2703

1292

2704

if(not debug){

1293

2705

avahi_set_log_function(empty_log);

1294

2706

}

1295

1296

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

1297

struct dirent **direntries;

1298

ret = scandir(sys_class_net, &direntries, good_interface,

1299

alphasort);

1300

if(ret >= 1){

1301

/* Pick the first good interface */

1302

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

1303

if(debug){

1304

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

1305

}

1306

if(interface == NULL){

1307

perror("malloc");

1308

free(direntries);

1309

exitcode = EXIT_FAILURE;

1310

goto end;

1311

}

1312

free(direntries);

1313

} else {

1314

free(direntries);

1315

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

1316

exitcode = EXIT_FAILURE;

1317

goto end;

1318

}

1319

}

1320

2707

1321

2708

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

1322

2709

from the signal handler */

1323

2710

/* Initialize the pseudo-RNG for Avahi */

1324

2711

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

1325

mc.simple_poll = avahi_simple_poll_new();

1326

if(mc.simple_poll == NULL){

1327

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

2712

simple_poll = avahi_simple_poll_new();

2713

if(simple_poll == NULL){

2714

fprintf_plus(stderr,

2715

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

1328

2716

exitcode = EX_UNAVAILABLE;

1329

2717

goto end;

1330

2718

}

1332

2720

sigemptyset(&sigterm_action.sa_mask);

1333

2721

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1334

2722

if(ret == -1){

1335

perror("sigaddset");

2723

perror_plus("sigaddset");

1336

2724

exitcode = EX_OSERR;

1337

2725

goto end;

1338

2726

}

1339

2727

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1340

2728

if(ret == -1){

1341

perror("sigaddset");

2729

perror_plus("sigaddset");

1342

2730

exitcode = EX_OSERR;

1343

2731

goto end;

1344

2732

}

1345

2733

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1346

2734

if(ret == -1){

1347

perror("sigaddset");

2735

perror_plus("sigaddset");

1348

2736

exitcode = EX_OSERR;

1349

2737

goto end;

1350

2738

}

1354

2742

*/

1355

2743

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1356

2744

if(ret == -1){

1357

perror("sigaction");

2745

perror_plus("sigaction");

1358

2746

return EX_OSERR;

1359

2747

}

1360

2748

if(old_sigterm_action.sa_handler != SIG_IGN){

1361

2749

ret = sigaction(SIGINT, &sigterm_action, NULL);

1362

2750

if(ret == -1){

1363

perror("sigaction");

2751

perror_plus("sigaction");

1364

2752

exitcode = EX_OSERR;

1365

2753

goto end;

1366

2754

}

1367

2755

}

1368

2756

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1369

2757

if(ret == -1){

1370

perror("sigaction");

2758

perror_plus("sigaction");

1371

2759

return EX_OSERR;

1372

2760

}

1373

2761

if(old_sigterm_action.sa_handler != SIG_IGN){

1374

2762

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1375

2763

if(ret == -1){

1376

perror("sigaction");

2764

perror_plus("sigaction");

1377

2765

exitcode = EX_OSERR;

1378

2766

goto end;

1379

2767

}

1380

2768

}

1381

2769

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1382

2770

if(ret == -1){

1383

perror("sigaction");

2771

perror_plus("sigaction");

1384

2772

return EX_OSERR;

1385

2773

}

1386

2774

if(old_sigterm_action.sa_handler != SIG_IGN){

1387

2775

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1388

2776

if(ret == -1){

1389

perror("sigaction");

1390

exitcode = EX_OSERR;

1391

goto end;

1392

}

1393

}

1394

1395

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

1396

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

1397

if_index = (AvahiIfIndex) if_nametoindex(interface);

1398

if(if_index == 0){

1399

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

1400

exitcode = EX_UNAVAILABLE;

1401

goto end;

1402

}

1403

1404

if(quit_now){

1405

goto end;

1406

}

1407

1408

/* Re-raise priviliges */

1409

errno = 0;

1410

ret = seteuid(0);

1411

if(ret == -1){

1412

perror("seteuid");

1413

}

1414

1415

#ifdef __linux__

1416

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1417

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

1418

ret = klogctl(8, NULL, 5);

1419

bool restore_loglevel = true;

1420

if(ret == -1){

1421

restore_loglevel = false;

1422

perror("klogctl");

1423

}

1424

#endif /* __linux__ */

1425

1426

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1427

if(sd < 0){

1428

perror("socket");

1429

exitcode = EX_OSERR;

1430

#ifdef __linux__

1431

if(restore_loglevel){

1432

ret = klogctl(7, NULL, 0);

1433

if(ret == -1){

1434

perror("klogctl");

1435

}

1436

}

1437

#endif /* __linux__ */

1438

/* Lower privileges */

1439

errno = 0;

1440

ret = seteuid(uid);

1441

if(ret == -1){

1442

perror("seteuid");

1443

}

1444

goto end;

1445

}

1446

strcpy(network.ifr_name, interface);

1447

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

1448

if(ret == -1){

1449

perror("ioctl SIOCGIFFLAGS");

1450

#ifdef __linux__

1451

if(restore_loglevel){

1452

ret = klogctl(7, NULL, 0);

1453

if(ret == -1){

1454

perror("klogctl");

1455

}

1456

}

1457

#endif /* __linux__ */

1458

exitcode = EX_OSERR;

1459

/* Lower privileges */

1460

errno = 0;

1461

ret = seteuid(uid);

1462

if(ret == -1){

1463

perror("seteuid");

1464

}

1465

goto end;

1466

}

1467

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

1468

network.ifr_flags |= IFF_UP;

1469

take_down_interface = true;

1470

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

1471

if(ret == -1){

1472

take_down_interface = false;

1473

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1474

exitcode = EX_OSERR;

1475

#ifdef __linux__

1476

if(restore_loglevel){

1477

ret = klogctl(7, NULL, 0);

1478

if(ret == -1){

1479

perror("klogctl");

2777

perror_plus("sigaction");

2778

exitcode = EX_OSERR;

2779

goto end;

2780

}

2781

}

2782

2783

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

2784

if(mc.interfaces == NULL){

2785

struct dirent **direntries = NULL;

2786

/* Look for any good interfaces */

2787

ret = scandir(sys_class_net, &direntries, good_interface,

2788

alphasort);

2789

if(ret >= 1){

2790

/* Add all found interfaces to interfaces list */

2791

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

2792

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

2793

direntries[i]->d_name);

2794

if(ret_errno != 0){

2795

errno = ret_errno;

2796

perror_plus("argz_add");

2797

free(direntries[i]);

2798

continue;

2799

}

2800

if(debug){

2801

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

2802

direntries[i]->d_name);

2803

}

2804

free(direntries[i]);

2805

}

2806

free(direntries);

2807

} else {

2808

if(ret == 0){

2809

free(direntries);

2810

}

2811

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

2812

exitcode = EXIT_FAILURE;

2813

goto end;

2814

}

2815

}

2816

2817

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

2818

{

2819

char *interface = NULL;

2820

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

2821

interface))){

2822

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

2823

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

2824

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

2825

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

2826

interface);

2827

interface = NULL;

2828

while((interface = argz_next(mc.interfaces,

2829

mc.interfaces_size, interface))){

2830

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

2831

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

2832

interface);

2833

interface = NULL;

1480

2834

}

1481

2835

}

1482

#endif /* __linux__ */

1483

/* Lower privileges */

1484

errno = 0;

1485

ret = seteuid(uid);

1486

if(ret == -1){

1487

perror("seteuid");

1488

}

1489

goto end;

1490

}

1491

}

1492

/* sleep checking until interface is running */

1493

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

1494

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

1495

if(ret == -1){

1496

perror("ioctl SIOCGIFFLAGS");

1497

} else if(network.ifr_flags & IFF_RUNNING){

1498

2836

break;

1499

2837

}

1500

struct timespec sleeptime = { .tv_nsec = 250000000 };

1501

ret = nanosleep(&sleeptime, NULL);

1502

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

1503

perror("nanosleep");

1504

}

1505

}

1506

if(not take_down_interface){

1507

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

1508

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

1509

if(ret == -1){

1510

perror("close");

1511

}

1512

}

1513

#ifdef __linux__

1514

if(restore_loglevel){

1515

/* Restores kernel loglevel to default */

1516

ret = klogctl(7, NULL, 0);

1517

if(ret == -1){

1518

perror("klogctl");

1519

}

1520

}

1521

#endif /* __linux__ */

1522

/* Lower privileges */

1523

errno = 0;

1524

if(take_down_interface){

1525

/* Lower privileges */

1526

ret = seteuid(uid);

1527

if(ret == -1){

1528

perror("seteuid");

1529

}

1530

} else {

1531

/* Lower privileges permanently */

1532

ret = setuid(uid);

1533

if(ret == -1){

1534

perror("setuid");

1535

}

1536

}

2838

bool interface_was_up = interface_is_up(interface);

2839

errno = bring_up_interface(interface, delay);

2840

if(not interface_was_up){

2841

if(errno != 0){

2842

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

2843

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

2844

} else {

2845

errno = argz_add(&interfaces_to_take_down,

2846

&interfaces_to_take_down_size,

2847

interface);

2848

if(errno != 0){

2849

perror_plus("argz_add");

2850

}

2851

}

2852

}

2853

}

2854

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

2855

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

2856

}

2857

}

2858

2859

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

2860

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

2861

if(debug){

2862

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

2863

mc.interfaces);

2864

}

2865

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

1537

2866

}

1538

2867

1539

2868

if(quit_now){

1540

2869

goto end;

1541

2870

}

1542

2871

1543

ret = init_gnutls_global(pubkey, seckey);

2872

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

1544

2873

if(ret == -1){

1545

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

2874

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

1546

2875

exitcode = EX_UNAVAILABLE;

1547

2876

goto end;

1548

2877

} else {

1553

2882

goto end;

1554

2883

}

1555

2884

1556

tempdir_created = true;

1557

if(mkdtemp(tempdir) == NULL){

1558

tempdir_created = false;

1559

perror("mkdtemp");

2885

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

2886

tempdir = mkdtemp(run_tempdir);

2887

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

2888

if(debug){

2889

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

2890

run_tempdir, old_tempdir);

2891

}

2892

tempdir = mkdtemp(old_tempdir);

2893

}

2894

if(tempdir == NULL){

2895

perror_plus("mkdtemp");

1560

2896

goto end;

1561

2897

}

1562

2898

1564

2900

goto end;

1565

2901

}

1566

2902

1567

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

1568

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

2903

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

2904

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

1569

2905

exitcode = EX_UNAVAILABLE;

1570

2906

goto end;

1571

2907

} else {

1580

2916

/* Connect directly, do not use Zeroconf */

1581

2917

/* (Mainly meant for debugging) */

1582

2918

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

2919

1583

2920

if(address == NULL){

1584

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

2921

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

1585

2922

exitcode = EX_USAGE;

1586

2923

goto end;

1587

2924

}

1590

2927

goto end;

1591

2928

}

1592

2929

1593

uint16_t port;

2930

in_port_t port;

1594

2931

errno = 0;

1595

2932

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

1596

2933

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

1597

or tmpmax != (uint16_t)tmpmax){

1598

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

2934

or tmpmax != (in_port_t)tmpmax){

2935

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

1599

2936

exitcode = EX_USAGE;

1600

2937

goto end;

1601

2938

}

1602

2939

1603

2940

if(quit_now){

1604

2941

goto end;

1605

2942

}

1606

2943

1607

port = (uint16_t)tmpmax;

2944

port = (in_port_t)tmpmax;

1608

2945

*address = '\0';

1609

address = connect_to;

1610

2946

/* Colon in address indicates IPv6 */

1611

2947

int af;

1612

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

2948

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

1613

2949

af = AF_INET6;

2950

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

2951

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

2952

{

2953

connect_to++;

2954

address[-1] = '\0';

2955

}

1614

2956

} else {

1615

2957

af = AF_INET;

1616

2958

}

2959

address = connect_to;

1617

2960

1618

2961

if(quit_now){

1619

2962

goto end;

1620

2963

}

1621

2964

1622

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

1623

if(ret < 0){

1624

switch(errno){

1625

case ENETUNREACH:

1626

case EHOSTDOWN:

1627

case EHOSTUNREACH:

1628

exitcode = EX_NOHOST;

1629

break;

1630

case EINVAL:

1631

exitcode = EX_USAGE;

1632

break;

1633

case EIO:

1634

exitcode = EX_IOERR;

1635

break;

1636

case EPROTO:

1637

exitcode = EX_PROTOCOL;

1638

break;

1639

default:

1640

exitcode = EX_OSERR;

1641

break;

1642

}

1643

} else {

2965

while(not quit_now){

2966

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

2967

&mc);

2968

if(quit_now or ret == 0){

2969

break;

2970

}

2971

if(debug){

2972

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

2973

(int)retry_interval);

2974

}

2975

sleep((unsigned int)retry_interval);

2976

}

2977

2978

if(not quit_now){

1644

2979

exitcode = EXIT_SUCCESS;

1645

2980

}

2981

1646

2982

goto end;

1647

2983

}

1648

2984

1660

2996

config.publish_domain = 0;

1661

2997

1662

2998

/* Allocate a new server */

1663

mc.server = avahi_server_new(avahi_simple_poll_get

1664

(mc.simple_poll), &config, NULL,

1665

NULL, &error);

2999

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3000

&config, NULL, NULL, &ret);

1666

3001

1667

3002

/* Free the Avahi configuration data */

1668

3003

avahi_server_config_free(&config);

1670

3005

1671

3006

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

1672

3007

if(mc.server == NULL){

1673

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

1674

avahi_strerror(error));

3008

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

3009

avahi_strerror(ret));

1675

3010

exitcode = EX_UNAVAILABLE;

1676

3011

goto end;

1677

3012

}

1683

3018

/* Create the Avahi service browser */

1684

3019

sb = avahi_s_service_browser_new(mc.server, if_index,

1685

3020

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1686

NULL, 0, browse_callback, NULL);

3021

NULL, 0, browse_callback,

3022

(void *)&mc);

1687

3023

if(sb == NULL){

1688

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

1689

avahi_strerror(avahi_server_errno(mc.server)));

3024

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

3025

avahi_strerror(avahi_server_errno(mc.server)));

1690

3026

exitcode = EX_UNAVAILABLE;

1691

3027

goto end;

1692

3028

}

1698

3034

/* Run the main loop */

1699

3035

1700

3036

if(debug){

1701

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

3037

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

1702

3038

}

1703

3039

1704

avahi_simple_poll_loop(mc.simple_poll);

3040

ret = avahi_loop_with_timeout(simple_poll,

3041

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

3042

if(debug){

3043

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

3044

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

3045

}

1705

3046

1706

3047

end:

1707

3048

1708

3049

if(debug){

1709

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

3050

if(signal_received){

3051

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

3052

argv[0], signal_received,

3053

strsignal(signal_received));

3054

} else {

3055

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

3056

}

1710

3057

}

1711

3058

1712

3059

/* Cleanup things */

3060

free(mc.interfaces);

3061

1713

3062

if(sb != NULL)

1714

3063

avahi_s_service_browser_free(sb);

1715

3064

1716

3065

if(mc.server != NULL)

1717

3066

avahi_server_free(mc.server);

1718

3067

1719

if(mc.simple_poll != NULL)

1720

avahi_simple_poll_free(mc.simple_poll);

3068

if(simple_poll != NULL)

3069

avahi_simple_poll_free(simple_poll);

1721

3070

1722

3071

if(gnutls_initialized){

1723

3072

gnutls_certificate_free_credentials(mc.cred);

1724

gnutls_global_deinit();

1725

3073

gnutls_dh_params_deinit(mc.dh_params);

1726

3074

}

1727

3075

1729

3077

gpgme_release(mc.ctx);

1730

3078

}

1731

3079

1732

/* Take down the network interface */

1733

if(take_down_interface){

1734

/* Re-raise priviliges */

1735

errno = 0;

1736

ret = seteuid(0);

1737

if(ret == -1){

1738

perror("seteuid");

1739

}

1740

if(geteuid() == 0){

1741

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

1742

if(ret == -1){

1743

perror("ioctl SIOCGIFFLAGS");

1744

} else if(network.ifr_flags & IFF_UP) {

1745

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

1746

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

1747

if(ret == -1){

1748

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1749

}

1750

}

1751

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

1752

if(ret == -1){

1753

perror("close");

1754

}

1755

/* Lower privileges permanently */

1756

errno = 0;

1757

ret = setuid(uid);

1758

if(ret == -1){

1759

perror("setuid");

1760

}

1761

}

1762

}

1763

1764

/* Removes the temp directory used by GPGME */

1765

if(tempdir_created){

1766

DIR *d;

1767

struct dirent *direntry;

1768

d = opendir(tempdir);

1769

if(d == NULL){

1770

if(errno != ENOENT){

1771

perror("opendir");

1772

}

1773

} else {

1774

while(true){

1775

direntry = readdir(d);

1776

if(direntry == NULL){

1777

break;

1778

}

1779

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

1780

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

1781

and (direntry->d_name[1] == '\0'

1782

or (direntry->d_name[1] == '.'

1783

and direntry->d_name[2] == '\0'))){

1784

continue;

1785

}

1786

char *fullname = NULL;

1787

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

1788

direntry->d_name);

1789

if(ret < 0){

1790

perror("asprintf");

1791

continue;

1792

}

1793

ret = remove(fullname);

1794

if(ret == -1){

1795

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

1796

strerror(errno));

1797

}

1798

free(fullname);

1799

}

1800

closedir(d);

1801

}

1802

ret = rmdir(tempdir);

1803

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

1804

perror("rmdir");

1805

}

3080

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

3081

has seen */

3082

if(mc.current_server != NULL){

3083

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

3084

while(mc.current_server != NULL){

3085

server *next = mc.current_server->next;

3086

#ifdef __GNUC__

3087

#pragma GCC diagnostic push

3088

#pragma GCC diagnostic ignored "-Wcast-qual"

3089

#endif

3090

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

3091

#ifdef __GNUC__

3092

#pragma GCC diagnostic pop

3093

#endif

3094

free(mc.current_server);

3095

mc.current_server = next;

3096

}

3097

}

3098

3099

/* Re-raise privileges */

3100

{

3101

ret = raise_privileges();

3102

if(ret != 0){

3103

errno = ret;

3104

perror_plus("Failed to raise privileges");

3105

} else {

3106

3107

/* Run network hooks */

3108

run_network_hooks("stop", interfaces_hooks != NULL ?

3109

interfaces_hooks : "", delay);

3110

3111

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

3112

{

3113

char *interface = NULL;

3114

while((interface = argz_next(interfaces_to_take_down,

3115

interfaces_to_take_down_size,

3116

interface))){

3117

ret = take_down_interface(interface);

3118

if(ret != 0){

3119

errno = ret;

3120

perror_plus("Failed to take down interface");

3121

}

3122

}

3123

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

3124

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

3125

" down\n");

3126

}

3127

}

3128

}

3129

3130

ret = lower_privileges_permanently();

3131

if(ret != 0){

3132

errno = ret;

3133

perror_plus("Failed to lower privileges permanently");

3134

}

3135

}

3136

3137

free(interfaces_to_take_down);

3138

free(interfaces_hooks);

3139

3140

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

3141

uintmax_t level){

3142

struct dirent **direntries = NULL;

3143

int dret;

3144

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

3145

O_RDONLY

3146

| O_NOFOLLOW

3147

| O_DIRECTORY

3148

| O_PATH));

3149

if(dir_fd == -1){

3150

perror_plus("open");

3151

return;

3152

}

3153

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

3154

notdotentries, alphasort);

3155

if(numentries >= 0){

3156

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

3157

if(debug){

3158

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

3159

dirname, direntries[i]->d_name);

3160

}

3161

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

3162

if(dret == -1){

3163

if(errno == EISDIR){

3164

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

3165

AT_REMOVEDIR);

3166

}

3167

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

3168

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

3169

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

3170

/* Recurse only in this special case */

3171

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

3172

dret = 0;

3173

}

3174

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

3175

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

3176

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

3177

}

3178

}

3179

free(direntries[i]);

3180

}

3181

3182

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

3183

free(direntries);

3184

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3185

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

3186

perror_plus("rmdir");

3187

}

3188

} else {

3189

perror_plus("scandirat");

3190

}

3191

close(dir_fd);

3192

}

3193

3194

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

3195

if(tempdir != NULL){

3196

clean_dir_at(-1, tempdir, 0);

1806

3197

}

1807

3198

1808

3199

if(quit_now){

1812

3203

&old_sigterm_action,

1813

3204

NULL));

1814

3205

if(ret == -1){

1815

perror("sigaction");

3206

perror_plus("sigaction");

1816

3207

}

1817

3208

do {

1818

3209

ret = raise(signal_received);

1819

3210

} while(ret != 0 and errno == EINTR);

1820

3211

if(ret != 0){

1821

perror("raise");

3212

perror_plus("raise");

1822

3213

abort();

1823

3214

}

1824

3215

TEMP_FAILURE_RETRY(pause());