/mandos/trunk : revision 738.1.5

9

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

10

*

11

* Everything else is

12

13

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

26

* along with this program. If not, see

27

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

28

*

29

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

29

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

30

*/

31

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

41

42

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

43

stdout, ferror(), remove() */

44

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

43

stdout, ferror() */

44

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

45

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

46

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

47

strtof(), abort() */

53

sockaddr_in6, PF_INET6,

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

56

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

56

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

57

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

58

inet_pton(), connect() */

59

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

61

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

61

62

*/

62

63

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

63

64

strtoimax() */

64

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

65

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

66

program_invocation_short_name */

67

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

73

*/

74

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

75

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

76

setgid(), pause() */

77

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

76

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

77

unlinkat() */

78

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

78

79

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

79

80

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

80

81

argp_state, struct argp,

85

86

raise() */

86

87

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

87

88

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

89

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

90

WEXITSTATUS(), WTERMSIG() */

91

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

92

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

93

argz_delete(), argz_append(),

94

argz_stringify(), argz_add(),

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

88

98

89

99

#ifdef __linux__

90

100

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

108

118

init_gnutls_session(),

109

119

GNUTLS_* */

110

120

#include <gnutls/openpgp.h>

111

/* gnutls_certificate_set_openpgp_key_file(),

112

GNUTLS_OPENPGP_FMT_BASE64 */

121

/* gnutls_certificate_set_openpgp_key_file(),

122

GNUTLS_OPENPGP_FMT_BASE64 */

113

123

114

124

/* GPGME */

115

125

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

123

133

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

124

134

#define SECKEY "seckey.txt"

125

135

#define PUBKEY "pubkey.txt"

136

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

126

137

127

138

bool debug = false;

128

139

static const char mandos_protocol_version[] = "1";

129

140

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

130

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

141

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

131

142

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

132

143

char *connect_to = NULL;

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

133

148

134

149

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

135

150

typedef struct server{

136

151

const char *ip;

137

uint16_t port;

152

in_port_t port;

138

153

AvahiIfIndex if_index;

139

154

int af;

140

155

struct timespec last_seen;

144

159

145

160

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

146

161

typedef struct {

147

AvahiSimplePoll *simple_poll;

148

162

AvahiServer *server;

149

163

gnutls_certificate_credentials_t cred;

150

164

unsigned int dh_bits;

152

166

const char *priority;

153

167

gpgme_ctx_t ctx;

154

168

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

155

171

} mandos_context;

156

172

157

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

158

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

159

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

162

175

163

176

sig_atomic_t quit_now = 0;

164

177

int signal_received = 0;

165

178

166

179

/* Function to use when printing errors */

167

180

void perror_plus(const char *print_text){

181

int e = errno;

168

182

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

169

183

program_invocation_short_name);

184

errno = e;

170

185

perror(print_text);

171

186

}

172

187

188

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

189

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

190

va_list ap;

191

va_start (ap, format);

192

193

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

194

program_invocation_short_name));

195

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

196

}

197

173

198

/*

174

199

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

175

200

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

176

201

* "buffer_length" is how much is already used.

177

202

*/

203

__attribute__((nonnull, warn_unused_result))

178

204

size_t incbuffer(char **buffer, size_t buffer_length,

179

size_t buffer_capacity){

205

size_t buffer_capacity){

180

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

181

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

182

if(buffer == NULL){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

183

213

return 0;

184

214

}

215

*buffer = new_buf;

185

216

buffer_capacity += BUFFER_SIZE;

186

217

}

187

218

return buffer_capacity;

188

219

}

189

220

190

221

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

191

int add_server(const char *ip, uint16_t port,

192

AvahiIfIndex if_index,

193

int af){

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

194

225

int ret;

195

226

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

196

227

if(new_server == NULL){

197

228

perror_plus("malloc");

198

return -1;

229

return false;

199

230

}

200

231

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

201

.port = port,

202

.if_index = if_index,

203

.af = af };

232

.port = port,

233

.if_index = if_index,

234

.af = af };

204

235

if(new_server->ip == NULL){

205

236

perror_plus("strdup");

206

return -1;

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

207

253

}

208

254

/* Special case of first server */

209

if (mc.current_server == NULL){

255

if(*current_server == NULL){

210

256

new_server->next = new_server;

211

257

new_server->prev = new_server;

212

mc.current_server = new_server;

213

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

258

*current_server = new_server;

214

259

} else {

215

new_server->next = mc.current_server;

216

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

260

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

261

new_server->next = *current_server;

262

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

217

263

new_server->prev->next = new_server;

218

mc.current_server->prev = new_server;

219

}

220

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

221

if(ret == -1){

222

perror_plus("clock_gettime");

223

return -1;

224

}

225

return 0;

264

(*current_server)->prev = new_server;

265

}

266

return true;

226

267

}

227

268

228

269

/*

229

270

* Initialize GPGME.

230

271

*/

231

static bool init_gpgme(const char *seckey,

232

const char *pubkey, const char *tempdir){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

233

277

gpgme_error_t rc;

234

278

gpgme_engine_info_t engine_info;

235

279

236

237

280

/*

238

281

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

239

282

*/

240

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

241

284

int ret;

242

285

int fd;

243

286

gpgme_data_t pgp_data;

250

293

251

294

rc = gpgme_data_new_from_fd(&pgp_data, fd);

252

295

if(rc != GPG_ERR_NO_ERROR){

253

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

254

gpgme_strsource(rc), gpgme_strerror(rc));

296

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

297

gpgme_strsource(rc), gpgme_strerror(rc));

255

298

return false;

256

299

}

257

300

258

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

259

302

if(rc != GPG_ERR_NO_ERROR){

260

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

261

gpgme_strsource(rc), gpgme_strerror(rc));

303

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

304

gpgme_strsource(rc), gpgme_strerror(rc));

262

305

return false;

263

306

}

264

307

271

314

}

272

315

273

316

if(debug){

274

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

317

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

275

318

}

276

319

277

320

/* Init GPGME */

278

321

gpgme_check_version(NULL);

279

322

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

280

323

if(rc != GPG_ERR_NO_ERROR){

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

283

326

return false;

284

327

}

285

328

286

329

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

287

330

rc = gpgme_get_engine_info(&engine_info);

288

331

if(rc != GPG_ERR_NO_ERROR){

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

291

334

return false;

292

335

}

293

336

while(engine_info != NULL){

299

342

engine_info = engine_info->next;

300

343

}

301

344

if(engine_info == NULL){

302

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

345

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

346

tempdir);

303

347

return false;

304

348

}

305

349

306

350

/* Create new GPGME "context" */

307

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

351

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

308

352

if(rc != GPG_ERR_NO_ERROR){

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

353

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

354

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

355

gpgme_strerror(rc));

311

356

return false;

312

357

}

313

358

322

367

* Decrypt OpenPGP data.

323

368

* Returns -1 on error

324

369

*/

370

__attribute__((nonnull, warn_unused_result))

325

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

326

372

size_t crypto_size,

327

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

328

375

gpgme_data_t dh_crypto, dh_plain;

329

376

gpgme_error_t rc;

330

377

ssize_t ret;

332

379

ssize_t plaintext_length = 0;

333

380

334

381

if(debug){

335

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

382

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

336

383

}

337

384

338

385

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

339

386

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

340

387

0);

341

388

if(rc != GPG_ERR_NO_ERROR){

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

344

391

return -1;

345

392

}

346

393

347

394

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

348

395

rc = gpgme_data_new(&dh_plain);

349

396

if(rc != GPG_ERR_NO_ERROR){

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

352

400

gpgme_data_release(dh_crypto);

353

401

return -1;

354

402

}

355

403

356

404

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

357

405

data buffer */

358

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

406

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

359

407

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

362

410

plaintext_length = -1;

363

411

if(debug){

364

412

gpgme_decrypt_result_t result;

365

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

366

414

if(result == NULL){

367

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

415

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

368

416

} else {

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

373

421

if(result->file_name != NULL){

374

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

422

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

375

423

}

376

424

gpgme_recipient_t recipient;

377

425

recipient = result->recipients;

378

426

while(recipient != NULL){

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

385

434

recipient = recipient->next;

386

435

}

387

436

}

390

439

}

391

440

392

441

if(debug){

393

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

442

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

394

443

}

395

444

396

445

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

403

452

*plaintext = NULL;

404

453

while(true){

405

454

plaintext_capacity = incbuffer(plaintext,

406

(size_t)plaintext_length,

407

plaintext_capacity);

455

(size_t)plaintext_length,

456

plaintext_capacity);

408

457

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

412

461

}

413

462

414

463

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

427

476

}

428

477

429

478

if(debug){

430

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

479

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

431

480

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

432

481

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

433

482

}

444

493

return plaintext_length;

445

494

}

446

495

447

static const char * safer_gnutls_strerror(int value){

448

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

449

-Wunreachable-code */

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

450

499

if(ret == NULL)

451

500

ret = "(unknown)";

452

501

return ret;

453

502

}

454

503

455

504

/* GnuTLS log function callback */

505

__attribute__((nonnull))

456

506

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

457

507

const char* string){

458

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

508

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

459

509

}

460

510

511

__attribute__((nonnull, warn_unused_result))

461

512

static int init_gnutls_global(const char *pubkeyfilename,

462

const char *seckeyfilename){

513

const char *seckeyfilename,

514

mandos_context *mc){

463

515

int ret;

464

516

465

517

if(debug){

466

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

518

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

467

519

}

468

520

469

521

ret = gnutls_global_init();

470

522

if(ret != GNUTLS_E_SUCCESS){

471

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

472

safer_gnutls_strerror(ret));

523

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

524

safer_gnutls_strerror(ret));

473

525

return -1;

474

526

}

475

527

482

534

}

483

535

484

536

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

486

538

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

539

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

540

safer_gnutls_strerror(ret));

489

541

gnutls_global_deinit();

490

542

return -1;

491

543

}

492

544

493

545

if(debug){

494

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

495

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

496

seckeyfilename);

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

497

550

}

498

551

499

552

ret = gnutls_certificate_set_openpgp_key_file

500

(mc.cred, pubkeyfilename, seckeyfilename,

553

(mc->cred, pubkeyfilename, seckeyfilename,

501

554

GNUTLS_OPENPGP_FMT_BASE64);

502

555

if(ret != GNUTLS_E_SUCCESS){

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

508

561

goto globalfail;

509

562

}

510

563

511

564

/* GnuTLS server initialization */

512

ret = gnutls_dh_params_init(&mc.dh_params);

565

ret = gnutls_dh_params_init(&mc->dh_params);

513

566

if(ret != GNUTLS_E_SUCCESS){

514

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

515

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

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

516

570

goto globalfail;

517

571

}

518

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

572

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

519

573

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

574

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

575

safer_gnutls_strerror(ret));

522

576

goto globalfail;

523

577

}

524

578

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

579

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

526

580

527

581

return 0;

528

582

529

583

globalfail:

530

584

531

gnutls_certificate_free_credentials(mc.cred);

585

gnutls_certificate_free_credentials(mc->cred);

532

586

gnutls_global_deinit();

533

gnutls_dh_params_deinit(mc.dh_params);

587

gnutls_dh_params_deinit(mc->dh_params);

534

588

return -1;

535

589

}

536

590

537

static int init_gnutls_session(gnutls_session_t *session){

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

538

594

int ret;

539

595

/* GnuTLS session creation */

540

596

do {

544

600

}

545

601

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

546

602

if(ret != GNUTLS_E_SUCCESS){

547

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

548

safer_gnutls_strerror(ret));

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

549

606

}

550

607

551

608

{

552

609

const char *err;

553

610

do {

554

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

611

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

555

612

if(quit_now){

556

613

gnutls_deinit(*session);

557

614

return -1;

558

615

}

559

616

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

560

617

if(ret != GNUTLS_E_SUCCESS){

561

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

562

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

563

safer_gnutls_strerror(ret));

618

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

619

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

620

safer_gnutls_strerror(ret));

564

621

gnutls_deinit(*session);

565

622

return -1;

566

623

}

568

625

569

626

do {

570

627

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

571

mc.cred);

628

mc->cred);

572

629

if(quit_now){

573

630

gnutls_deinit(*session);

574

631

return -1;

575

632

}

576

633

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

577

634

if(ret != GNUTLS_E_SUCCESS){

578

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

579

safer_gnutls_strerror(ret));

635

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

636

safer_gnutls_strerror(ret));

580

637

gnutls_deinit(*session);

581

638

return -1;

582

639

}

584

641

/* ignore client certificate if any. */

585

642

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

586

643

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

588

645

589

646

return 0;

590

647

}

593

650

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

594

651

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

595

652

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char delete_arg[] = "delete";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

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

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

if(helperdir_fd == -1){

779

perror_plus("open");

780

_exit(EX_UNAVAILABLE);

781

}

782

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

783

helper, O_RDONLY));

784

if(helper_fd == -1){

785

perror_plus("openat");

786

_exit(EX_UNAVAILABLE);

787

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

789

#ifdef __GNUC__

790

#pragma GCC diagnostic push

791

#pragma GCC diagnostic ignored "-Wcast-qual"

792

#endif

793

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

794

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

795

interface, NULL }, environ) == -1){

796

#ifdef __GNUC__

797

#pragma GCC diagnostic pop

798

#endif

799

perror_plus("fexecve");

800

_exit(EXIT_FAILURE);

801

}

802

}

803

if(pid == -1){

804

perror_plus("fork");

805

return false;

806

}

807

int status;

808

pid_t pret = -1;

809

errno = 0;

810

do {

811

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

812

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

813

int errno_raising = 0;

814

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

815

errno_raising = errno;

816

perror_plus("Failed to raise privileges in order to"

817

" kill helper program");

818

}

819

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

820

perror_plus("kill");

821

}

822

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

823

perror_plus("Failed to lower privileges after killing"

824

" helper program");

825

}

826

return false;

827

}

828

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

829

if(pret == -1){

830

perror_plus("waitpid");

831

return false;

832

}

833

if(WIFEXITED(status)){

834

if(WEXITSTATUS(status) != 0){

835

fprintf_plus(stderr, "Error: iprouteadddel exited"

836

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

837

return false;

838

}

839

return true;

840

}

841

if(WIFSIGNALED(status)){

842

fprintf_plus(stderr, "Error: iprouteadddel died by"

843

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

844

return false;

845

}

846

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

847

return false;

848

}

849

850

__attribute__((nonnull, warn_unused_result))

851

static bool add_local_route(const char *address,

852

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

854

}

855

856

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

858

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

860

}

861

596

862

/* Called when a Mandos server is found */

597

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

863

__attribute__((nonnull, warn_unused_result))

864

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

598

865

AvahiIfIndex if_index,

599

int af){

866

int af, mandos_context *mc){

600

867

int ret, tcp_sd = -1;

601

868

ssize_t sret;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

869

struct sockaddr_storage to;

606

870

char *buffer = NULL;

607

871

char *decrypted_buffer = NULL;

608

872

size_t buffer_length = 0;

611

875

int retval = -1;

612

876

gnutls_session_t session;

613

877

int pf; /* Protocol family */

878

bool route_added = false;

614

879

615

880

errno = 0;

616

881

627

892

pf = PF_INET;

628

893

break;

629

894

default:

630

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

895

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

631

896

errno = EINVAL;

632

897

return -1;

633

898

}

634

899

635

ret = init_gnutls_session(&session);

900

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

901

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

902

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

903

bool match = false;

904

{

905

char *interface = NULL;

906

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

907

interface))){

908

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

909

match = true;

910

break;

911

}

912

}

913

}

914

if(not match){

915

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

916

connect to the server */

917

if(debug){

918

char interface[IF_NAMESIZE];

919

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

920

perror_plus("if_indextoname");

921

} else {

922

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

923

" \"%s\"\n",

924

if_indextoname((unsigned int)if_index,

925

interface));

926

}

927

}

928

return -1;

929

}

930

}

931

932

ret = init_gnutls_session(&session, mc);

636

933

if(ret != 0){

637

934

return -1;

638

935

}

639

936

640

937

if(debug){

641

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

642

"\n", ip, port);

938

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

939

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

643

940

}

644

941

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

942

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

646

943

if(tcp_sd < 0){

647

944

int e = errno;

648

945

perror_plus("socket");

657

954

658

955

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

659

956

if(af == AF_INET6){

660

to.in6.sin6_family = (sa_family_t)af;

661

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

957

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

958

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

662

959

} else { /* IPv4 */

663

to.in.sin_family = (sa_family_t)af;

664

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

960

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

961

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

665

962

}

666

963

if(ret < 0 ){

667

964

int e = errno;

671

968

}

672

969

if(ret == 0){

673

970

int e = errno;

674

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

971

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

675

972

errno = e;

676

973

goto mandos_end;

677

974

}

678

975

if(af == AF_INET6){

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

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

685

-Wunreachable-code*/

976

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

977

if(IN6_IS_ADDR_LINKLOCAL

978

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

686

979

if(if_index == AVAHI_IF_UNSPEC){

687

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

688

" without a network interface\n");

980

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

981

" incomplete without a network interface\n");

689

982

errno = EINVAL;

690

983

goto mandos_end;

691

984

}

692

985

/* Set the network interface number as scope */

693

to.in6.sin6_scope_id = (uint32_t)if_index;

986

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

694

987

}

695

988

} else {

696

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

697

-Wconversion and

698

-Wunreachable-code */

989

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

699

990

}

700

991

701

992

if(quit_now){

709

1000

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

710

1001

perror_plus("if_indextoname");

711

1002

} else {

712

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

713

ip, interface, port);

1003

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

1004

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

714

1005

}

715

1006

} else {

716

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

717

port);

1007

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

1008

ip, (uintmax_t)port);

718

1009

}

719

1010

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

720

1011

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

721

const char *pcret;

722

if(af == AF_INET6){

723

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

724

sizeof(addrstr));

725

} else {

726

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

727

sizeof(addrstr));

728

}

729

if(pcret == NULL){

730

perror_plus("inet_ntop");

731

} else {

732

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

733

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

734

}

735

}

736

}

737

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

743

if(af == AF_INET6){

744

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

745

} else {

746

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

747

}

748

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

754

goto mandos_end;

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

1012

if(af == AF_INET6){

1013

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

1014

sizeof(struct sockaddr_in6),

1015

addrstr, sizeof(addrstr), NULL, 0,

1016

NI_NUMERICHOST);

1017

} else {

1018

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

1019

sizeof(struct sockaddr_in),

1020

addrstr, sizeof(addrstr), NULL, 0,

1021

NI_NUMERICHOST);

1022

}

1023

if(ret == EAI_SYSTEM){

1024

perror_plus("getnameinfo");

1025

} else if(ret != 0) {

1026

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

1027

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

1028

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

1029

}

1030

}

1031

1032

if(quit_now){

1033

errno = EINTR;

1034

goto mandos_end;

1035

}

1036

1037

while(true){

1038

if(af == AF_INET6){

1039

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

1040

sizeof(struct sockaddr_in6));

1041

} else {

1042

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

1043

sizeof(struct sockaddr_in));

1044

}

1045

if(ret < 0){

1046

if(errno == ENETUNREACH

1047

and if_index != AVAHI_IF_UNSPEC

1048

and connect_to == NULL

1049

and not route_added and

1050

((af == AF_INET6 and not

1051

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1052

&to)->sin6_addr)))

1053

or (af == AF_INET and

1054

/* Not a a IPv4LL address */

1055

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

1056

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

1057

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

1058

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

1059

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

1060

connect to a Mandos server announced by Avahi on a server

1061

host with a global address. Work around this by retrying

1062

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

1063

1064

Avahi bug reference:

1065

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

1066

https://bugs.debian.org/587961

1067

*/

1068

int e = errno;

1069

route_added = add_local_route(ip, if_index);

1070

if(route_added){

1071

continue;

1072

}

1073

errno = e;

1074

}

1075

if(errno != ECONNREFUSED or debug){

1076

int e = errno;

1077

perror_plus("connect");

1078

errno = e;

1079

}

1080

goto mandos_end;

1081

}

1082

1083

if(quit_now){

1084

errno = EINTR;

1085

goto mandos_end;

1086

}

1087

break;

760

1088

}

761

1089

762

1090

const char *out = mandos_protocol_version;

764

1092

while(true){

765

1093

size_t out_size = strlen(out);

766

1094

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

767

out_size - written));

1095

out_size - written));

768

1096

if(ret == -1){

769

1097

int e = errno;

770

1098

perror_plus("write");

790

1118

}

791

1119

792

1120

if(debug){

793

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

1121

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

794

1122

}

795

1123

796

1124

if(quit_now){

798

1126

goto mandos_end;

799

1127

}

800

1128

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1129

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

1130

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

1131

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

1132

gnutls_transport_set_ptr(session,

1133

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

803

1134

804

1135

if(quit_now){

805

1136

errno = EINTR;

816

1147

817

1148

if(ret != GNUTLS_E_SUCCESS){

818

1149

if(debug){

819

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

1150

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

820

1151

gnutls_perror(ret);

821

1152

}

822

1153

errno = EPROTO;

826

1157

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

827

1158

828

1159

if(debug){

829

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

830

ip);

1160

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1161

" %s\n", ip);

831

1162

}

832

1163

833

1164

while(true){

838

1169

}

839

1170

840

1171

buffer_capacity = incbuffer(&buffer, buffer_length,

841

buffer_capacity);

1172

buffer_capacity);

842

1173

if(buffer_capacity == 0){

843

1174

int e = errno;

844

1175

perror_plus("incbuffer");

871

1202

}

872

1203

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

873

1204

if(ret < 0){

874

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

1205

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

1206

"***\n");

875

1207

gnutls_perror(ret);

876

1208

errno = EPROTO;

877

1209

goto mandos_end;

878

1210

}

879

1211

break;

880

1212

default:

881

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

882

" encrypted session with Mandos server\n");

1213

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

1214

" encrypted session with Mandos server\n");

883

1215

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

1216

errno = EIO;

885

1217

goto mandos_end;

890

1222

}

891

1223

892

1224

if(debug){

893

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

1225

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

894

1226

}

895

1227

896

1228

if(quit_now){

908

1240

909

1241

if(buffer_length > 0){

910

1242

ssize_t decrypted_buffer_size;

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

1243

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1244

&decrypted_buffer, mc);

914

1245

if(decrypted_buffer_size >= 0){

915

1246

916

1247

written = 0;

926

1257

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

927

1258

int e = errno;

928

1259

if(debug){

929

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

930

strerror(errno));

1260

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

1261

strerror(errno));

931

1262

}

932

1263

errno = e;

933

1264

goto mandos_end;

942

1273

943

1274

mandos_end:

944

1275

{

1276

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

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

1279

" interface %d", ip, if_index);

1280

}

1281

}

945

1282

int e = errno;

946

1283

free(decrypted_buffer);

947

1284

free(buffer);

964

1301

return retval;

965

1302

}

966

1303

1304

__attribute__((nonnull))

967

1305

static void resolve_callback(AvahiSServiceResolver *r,

968

1306

AvahiIfIndex interface,

969

1307

AvahiProtocol proto,

977

1315

AVAHI_GCC_UNUSED AvahiStringList *txt,

978

1316

AVAHI_GCC_UNUSED AvahiLookupResultFlags

979

1317

flags,

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1318

void *mc){

1319

if(r == NULL){

1320

return;

1321

}

982

1322

983

1323

/* Called whenever a service has been resolved successfully or

984

1324

timed out */

985

1325

986

1326

if(quit_now){

1327

avahi_s_service_resolver_free(r);

987

1328

return;

988

1329

}

989

1330

990

1331

switch(event){

991

1332

default:

992

1333

case AVAHI_RESOLVER_FAILURE:

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1334

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

1335

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

1336

domain,

1337

avahi_strerror(avahi_server_errno

1338

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

996

1339

break;

997

1340

998

1341

case AVAHI_RESOLVER_FOUND:

1000

1343

char ip[AVAHI_ADDRESS_STR_MAX];

1001

1344

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

1002

1345

if(debug){

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1346

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

1347

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

1348

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

1006

1349

}

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1350

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

1351

interface,

1352

avahi_proto_to_af(proto),

1353

mc);

1009

1354

if(ret == 0){

1010

avahi_simple_poll_quit(mc.simple_poll);

1355

avahi_simple_poll_quit(simple_poll);

1011

1356

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1357

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

1358

avahi_proto_to_af(proto),

1359

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

1360

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

1361

" list\n", name);

1362

}

1014

1363

}

1015

1364

}

1016

1365

}

1026

1375

const char *domain,

1027

1376

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1028

1377

flags,

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1378

void *mc){

1379

if(b == NULL){

1380

return;

1381

}

1031

1382

1032

1383

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

1033

1384

is removed from the LAN */

1040

1391

default:

1041

1392

case AVAHI_BROWSER_FAILURE:

1042

1393

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1394

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

1395

avahi_strerror(avahi_server_errno

1396

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

1397

avahi_simple_poll_quit(simple_poll);

1046

1398

return;

1047

1399

1048

1400

case AVAHI_BROWSER_NEW:

1051

1403

the callback function is called the Avahi server will free the

1052

1404

resolver for us. */

1053

1405

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

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

1058

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

1406

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

1407

interface, protocol, name, type,

1408

domain, protocol, 0,

1409

resolve_callback, mc) == NULL)

1410

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

1411

" %s\n", name,

1412

avahi_strerror(avahi_server_errno

1413

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

1059

1414

break;

1060

1415

1061

1416

case AVAHI_BROWSER_REMOVE:

1064

1419

case AVAHI_BROWSER_ALL_FOR_NOW:

1065

1420

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1066

1421

if(debug){

1067

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

1422

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

1423

" searching...\n");

1068

1424

}

1069

1425

break;

1070

1426

}

1079

1435

signal_received = sig;

1080

1436

int old_errno = errno;

1081

1437

/* set main loop to exit */

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1438

if(simple_poll != NULL){

1439

avahi_simple_poll_quit(simple_poll);

1084

1440

}

1085

1441

errno = old_errno;

1086

1442

}

1087

1443

1444

__attribute__((nonnull, warn_unused_result))

1445

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

1446

int ret;

1447

error_t ret_errno;

1448

1449

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

1450

if(s < 0){

1451

ret_errno = errno;

1452

perror_plus("socket");

1453

errno = ret_errno;

1454

return false;

1455

}

1456

strcpy(ifr->ifr_name, ifname);

1457

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

if(ret == -1){

1459

if(debug){

1460

ret_errno = errno;

1461

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1463

}

1464

return false;

1465

}

1466

return true;

1467

}

1468

1469

__attribute__((nonnull, warn_unused_result))

1470

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

1471

1472

/* Reject the loopback device */

1473

if(ifr->ifr_flags & IFF_LOOPBACK){

1474

if(debug){

1475

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

1476

ifname);

1477

}

1478

return false;

1479

}

1480

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

1481

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

1482

if(debug){

1483

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

1484

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

1485

}

1486

return true;

1487

}

1488

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

1489

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

1490

if(debug){

1491

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1492

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

1493

}

1494

return false;

1495

}

1496

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

1497

if(ifr->ifr_flags & IFF_NOARP){

1498

if(debug){

1499

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

1500

ifname);

1501

}

1502

return false;

1503

}

1504

1505

/* Accept this device */

1506

if(debug){

1507

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

1508

}

1509

return true;

1510

}

1511

1088

1512

/*

1089

1513

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

1090

1514

* corresponds to an acceptable network device.

1091

1515

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

1092

1516

*/

1517

__attribute__((nonnull, warn_unused_result))

1093

1518

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

1519

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

1097

1520

return 0;

1098

1521

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

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

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1153

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1155

if(debug){

1156

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

1157

if_entry->d_name);

1158

}

1159

return 0;

1160

}

1161

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

1162

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

1163

if(debug){

1164

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

1165

if_entry->d_name);

1166

}

1167

return 1;

1168

}

1169

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

1170

if(not (flags & IFF_BROADCAST)){

1171

if(debug){

1172

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

1173

if_entry->d_name);

1174

}

1175

return 0;

1176

}

1177

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

1178

if(flags & IFF_NOARP){

1179

if(debug){

1180

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

1181

if_entry->d_name);

1182

}

1183

return 0;

1184

}

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

if_entry->d_name);

1522

1523

struct ifreq ifr;

1524

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

1525

if(debug){

1526

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

1527

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

1528

}

1529

return 0;

1530

}

1531

1532

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

1533

return 0;

1189

1534

}

1190

1535

return 1;

1191

1536

}

1192

1537

1538

/*

1539

* This function determines if a network interface is up.

1540

*/

1541

__attribute__((nonnull, warn_unused_result))

1542

bool interface_is_up(const char *interface){

1543

struct ifreq ifr;

1544

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

1545

if(debug){

1546

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

1547

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

1548

}

1549

return false;

1550

}

1551

1552

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

1553

}

1554

1555

/*

1556

* This function determines if a network interface is running

1557

*/

1558

__attribute__((nonnull, warn_unused_result))

1559

bool interface_is_running(const char *interface){

1560

struct ifreq ifr;

1561

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

1562

if(debug){

1563

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

1564

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

1565

}

1566

return false;

1567

}

1568

1569

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

1570

}

1571

1572

__attribute__((nonnull, pure, warn_unused_result))

1193

1573

int notdotentries(const struct dirent *direntry){

1194

1574

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

1195

1575

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

1201

1581

return 1;

1202

1582

}

1203

1583

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1584

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

1585

__attribute__((nonnull, warn_unused_result))

1586

int runnable_hook(const struct dirent *direntry){

1587

int ret;

1588

size_t sret;

1589

struct stat st;

1590

1591

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

1592

/* Empty name? */

1593

return 0;

1594

}

1595

1596

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

1597

"abcdefghijklmnopqrstuvwxyz"

1598

"0123456789"

1599

"_.-");

1600

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

1601

/* Contains non-allowed characters */

1602

if(debug){

1603

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

1604

direntry->d_name);

1605

}

1606

return 0;

1607

}

1608

1609

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

1610

if(ret == -1){

1611

if(debug){

1612

perror_plus("Could not stat hook");

1613

}

1614

return 0;

1615

}

1616

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

1617

/* Not a regular file */

1618

if(debug){

1619

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

1620

direntry->d_name);

1621

}

1622

return 0;

1623

}

1624

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

1625

/* Not executable */

1626

if(debug){

1627

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

1628

direntry->d_name);

1629

}

1630

return 0;

1631

}

1632

if(debug){

1633

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

1634

direntry->d_name);

1635

}

1636

return 1;

1637

}

1638

1639

__attribute__((nonnull, warn_unused_result))

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1641

mandos_context *mc){

1205

1642

int ret;

1206

1643

struct timespec now;

1207

1644

struct timespec waited_time;

1208

1645

intmax_t block_time;

1209

1646

1210

1647

while(true){

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

"Wait until first server is found. No timeout!\n");

1648

if(mc->current_server == NULL){

1649

if(debug){

1650

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

1651

" No timeout!\n");

1215

1652

}

1216

1653

ret = avahi_simple_poll_iterate(s, -1);

1217

1654

} else {

1218

if (debug){

1219

fprintf(stderr, "Check current_server if we should run it,"

1220

" or wait\n");

1655

if(debug){

1656

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

1657

" it, or wait\n");

1221

1658

}

1222

1659

/* the current time */

1223

1660

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1228

1665

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

1229

1666

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

1230

1667

waited_time.tv_sec = (now.tv_sec

1231

- mc.current_server->last_seen.tv_sec);

1668

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

1232

1669

waited_time.tv_nsec = (now.tv_nsec

1233

- mc.current_server->last_seen.tv_nsec);

1670

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

1234

1671

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

1235

1672

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

1236

1673

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

1238

1675

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

1239

1676

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

1240

1677

1241

if (debug){

1242

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

1678

if(debug){

1679

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

1680

block_time);

1243

1681

}

1244

1682

1245

1683

if(block_time <= 0){

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1684

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

1685

mc->current_server->port,

1686

mc->current_server->if_index,

1687

mc->current_server->af, mc);

1250

1688

if(ret == 0){

1251

avahi_simple_poll_quit(mc.simple_poll);

1689

avahi_simple_poll_quit(s);

1252

1690

return 0;

1253

1691

}

1254

1692

ret = clock_gettime(CLOCK_MONOTONIC,

1255

&mc.current_server->last_seen);

1693

&mc->current_server->last_seen);

1256

1694

if(ret == -1){

1257

1695

perror_plus("clock_gettime");

1258

1696

return -1;

1259

1697

}

1260

mc.current_server = mc.current_server->next;

1698

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

1261

1699

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

1262

1700

servers, but don't block */

1263

1701

}

1265

1703

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

1266

1704

}

1267

1705

if(ret != 0){

1268

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

1706

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

1269

1707

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

1270

1708

}

1271

1709

}

1272

1710

}

1273

1711

}

1274

1712

1713

__attribute__((nonnull))

1714

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

1715

const float delay){

1716

struct dirent **direntries = NULL;

1717

if(hookdir_fd == -1){

1718

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1719

| O_CLOEXEC);

1720

if(hookdir_fd == -1){

1721

if(errno == ENOENT){

1722

if(debug){

1723

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

1724

" found\n", hookdir);

1725

}

1726

} else {

1727

perror_plus("open");

1728

}

1729

return;

1730

}

1731

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1734

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

1735

runnable_hook, alphasort);

1736

#else /* not __GLIBC_PREREQ(2, 15) */

1737

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

1738

alphasort);

1739

#endif /* not __GLIBC_PREREQ(2, 15) */

1740

#else /* not __GLIBC__ */

1741

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

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1744

if(numhooks == -1){

1745

perror_plus("scandir");

1746

return;

1747

}

1748

struct dirent *direntry;

1749

int ret;

1750

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

1751

if(devnull == -1){

1752

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

1753

return;

1754

}

1755

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

1756

direntry = direntries[i];

1757

if(debug){

1758

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

1759

direntry->d_name);

1760

}

1761

pid_t hook_pid = fork();

1762

if(hook_pid == 0){

1763

/* Child */

1764

/* Raise privileges */

1765

errno = raise_privileges_permanently();

1766

if(errno != 0){

1767

perror_plus("Failed to raise privileges");

1768

_exit(EX_NOPERM);

1769

}

1770

/* Set group */

1771

errno = 0;

1772

ret = setgid(0);

1773

if(ret == -1){

1774

perror_plus("setgid");

1775

_exit(EX_NOPERM);

1776

}

1777

/* Reset supplementary groups */

1778

errno = 0;

1779

ret = setgroups(0, NULL);

1780

if(ret == -1){

1781

perror_plus("setgroups");

1782

_exit(EX_NOPERM);

1783

}

1784

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

1785

if(ret == -1){

1786

perror_plus("setenv");

1787

_exit(EX_OSERR);

1788

}

1789

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

1790

if(ret == -1){

1791

perror_plus("setenv");

1792

_exit(EX_OSERR);

1793

}

1794

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

1795

if(ret == -1){

1796

perror_plus("setenv");

1797

_exit(EX_OSERR);

1798

}

1799

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

1800

if(ret == -1){

1801

perror_plus("setenv");

1802

_exit(EX_OSERR);

1803

}

1804

char *delaystring;

1805

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

1806

if(ret == -1){

1807

perror_plus("asprintf");

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

1812

free(delaystring);

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

free(delaystring);

1817

if(connect_to != NULL){

1818

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

1819

if(ret == -1){

1820

perror_plus("setenv");

1821

_exit(EX_OSERR);

1822

}

1823

}

1824

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

1825

direntry->d_name,

1826

O_RDONLY));

1827

if(hook_fd == -1){

1828

perror_plus("openat");

1829

_exit(EXIT_FAILURE);

1830

}

1831

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

1832

perror_plus("close");

1833

_exit(EXIT_FAILURE);

1834

}

1835

ret = dup2(devnull, STDIN_FILENO);

1836

if(ret == -1){

1837

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

1838

_exit(EX_OSERR);

1839

}

1840

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

1841

if(ret == -1){

1842

perror_plus("close");

1843

_exit(EX_OSERR);

1844

}

1845

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1846

if(ret == -1){

1847

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

1848

_exit(EX_OSERR);

1849

}

1850

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

1851

environ) == -1){

1852

perror_plus("fexecve");

1853

_exit(EXIT_FAILURE);

1854

}

1855

} else {

1856

if(hook_pid == -1){

1857

perror_plus("fork");

1858

free(direntry);

1859

continue;

1860

}

1861

int status;

1862

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

1863

perror_plus("waitpid");

1864

free(direntry);

1865

continue;

1866

}

1867

if(WIFEXITED(status)){

1868

if(WEXITSTATUS(status) != 0){

1869

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

1870

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

1871

WEXITSTATUS(status));

1872

free(direntry);

1873

continue;

1874

}

1875

} else if(WIFSIGNALED(status)){

1876

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

1877

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

1878

WTERMSIG(status));

1879

free(direntry);

1880

continue;

1881

} else {

1882

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

1883

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

1884

free(direntry);

1885

continue;

1886

}

1887

}

1888

if(debug){

1889

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

1890

direntry->d_name);

1891

}

1892

free(direntry);

1893

}

1894

free(direntries);

1895

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

1896

perror_plus("close");

1897

} else {

1898

hookdir_fd = -1;

1899

}

1900

close(devnull);

1901

}

1902

1903

__attribute__((nonnull, warn_unused_result))

1904

error_t bring_up_interface(const char *const interface,

1905

const float delay){

1906

error_t old_errno = errno;

1907

int ret;

1908

struct ifreq network;

1909

unsigned int if_index = if_nametoindex(interface);

1910

if(if_index == 0){

1911

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

1912

errno = old_errno;

1913

return ENXIO;

1914

}

1915

1916

if(quit_now){

1917

errno = old_errno;

1918

return EINTR;

1919

}

1920

1921

if(not interface_is_up(interface)){

1922

error_t ret_errno = 0, ioctl_errno = 0;

1923

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

1924

ret_errno = errno;

1925

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

1926

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

1927

errno = old_errno;

1928

return ret_errno;

1929

}

1930

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

1931

1932

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

1933

if(sd == -1){

1934

ret_errno = errno;

1935

perror_plus("socket");

1936

errno = old_errno;

1937

return ret_errno;

1938

}

1939

1940

if(quit_now){

1941

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

1942

if(ret == -1){

1943

perror_plus("close");

1944

}

1945

errno = old_errno;

1946

return EINTR;

1947

}

1948

1949

if(debug){

1950

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

1951

interface);

1952

}

1953

1954

/* Raise privileges */

1955

ret_errno = raise_privileges();

1956

if(ret_errno != 0){

1957

errno = ret_errno;

1958

perror_plus("Failed to raise privileges");

1959

}

1960

1961

#ifdef __linux__

1962

int ret_linux;

1963

bool restore_loglevel = false;

1964

if(ret_errno == 0){

1965

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1966

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

1967

ret_linux = klogctl(8, NULL, 5);

1968

if(ret_linux == -1){

1969

perror_plus("klogctl");

1970

} else {

1971

restore_loglevel = true;

1972

}

1973

}

1974

#endif /* __linux__ */

1975

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

1976

ioctl_errno = errno;

1977

#ifdef __linux__

1978

if(restore_loglevel){

1979

ret_linux = klogctl(7, NULL, 0);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

}

1983

}

1984

#endif /* __linux__ */

1985

1986

/* If raise_privileges() succeeded above */

1987

if(ret_errno == 0){

1988

/* Lower privileges */

1989

ret_errno = lower_privileges();

1990

if(ret_errno != 0){

1991

errno = ret_errno;

1992

perror_plus("Failed to lower privileges");

1993

}

1994

}

1995

1996

/* Close the socket */

1997

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

1998

if(ret == -1){

1999

perror_plus("close");

2000

}

2001

2002

if(ret_setflags == -1){

2003

errno = ioctl_errno;

2004

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2005

errno = old_errno;

2006

return ioctl_errno;

2007

}

2008

} else if(debug){

2009

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

2010

interface);

2011

}

2012

2013

/* Sleep checking until interface is running.

2014

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

2015

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

2016

if(interface_is_running(interface)){

2017

break;

2018

}

2019

struct timespec sleeptime = { .tv_nsec = 250000000 };

2020

ret = nanosleep(&sleeptime, NULL);

2021

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

2022

perror_plus("nanosleep");

2023

}

2024

}

2025

2026

errno = old_errno;

2027

return 0;

2028

}

2029

2030

__attribute__((nonnull, warn_unused_result))

2031

error_t take_down_interface(const char *const interface){

2032

error_t old_errno = errno;

2033

struct ifreq network;

2034

unsigned int if_index = if_nametoindex(interface);

2035

if(if_index == 0){

2036

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

2037

errno = old_errno;

2038

return ENXIO;

2039

}

2040

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

2043

ret_errno = errno;

2044

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

2045

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

2046

errno = old_errno;

2047

return ret_errno;

2048

}

2049

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

2050

2051

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

2052

if(sd == -1){

2053

ret_errno = errno;

2054

perror_plus("socket");

2055

errno = old_errno;

2056

return ret_errno;

2057

}

2058

2059

if(debug){

2060

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

2061

interface);

2062

}

2063

2064

/* Raise privileges */

2065

ret_errno = raise_privileges();

2066

if(ret_errno != 0){

2067

errno = ret_errno;

2068

perror_plus("Failed to raise privileges");

2069

}

2070

2071

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

2072

ioctl_errno = errno;

2073

2074

/* If raise_privileges() succeeded above */

2075

if(ret_errno == 0){

2076

/* Lower privileges */

2077

ret_errno = lower_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to lower privileges");

2081

}

2082

}

2083

2084

/* Close the socket */

2085

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

2086

if(ret == -1){

2087

perror_plus("close");

2088

}

2089

2090

if(ret_setflags == -1){

2091

errno = ioctl_errno;

2092

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2093

errno = old_errno;

2094

return ioctl_errno;

2095

}

2096

} else if(debug){

2097

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

2098

interface);

2099

}

2100

2101

errno = old_errno;

2102

return 0;

2103

}

2104

1275

2105

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

2106

mandos_context mc = { .server = NULL, .dh_bits = 1024,

2107

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

2108

"+CTYPE-OPENPGP", .current_server = NULL,

2109

.interfaces = NULL, .interfaces_size = 0 };

1276

2110

AvahiSServiceBrowser *sb = NULL;

1277

int error;

2111

error_t ret_errno;

1278

2112

int ret;

1279

2113

intmax_t tmpmax;

1280

2114

char *tmp;

1281

2115

int exitcode = EXIT_SUCCESS;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1288

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

1289

bool tempdir_created = false;

2116

char *interfaces_to_take_down = NULL;

2117

size_t interfaces_to_take_down_size = 0;

2118

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

2119

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

2120

char *tempdir = NULL;

1290

2121

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1291

2122

const char *seckey = PATHDIR "/" SECKEY;

1292

2123

const char *pubkey = PATHDIR "/" PUBKEY;

2124

char *interfaces_hooks = NULL;

1293

2125

1294

2126

bool gnutls_initialized = false;

1295

2127

bool gpgme_initialized = false;

1357

2189

.group = 2 },

1358

2190

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

1359

2191

.arg = "SECONDS",

1360

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

2192

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

2193

.group = 2 },

2194

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

2195

.arg = "DIR",

2196

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

1361

2197

.group = 2 },

1362

2198

/*

1363

2199

* These reproduce what we would get without ARGP_NO_HELP

1382

2218

connect_to = arg;

1383

2219

break;

1384

2220

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

1385

interface = arg;

2221

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

2222

arg, (int)',');

2223

if(ret_errno != 0){

2224

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

2225

}

1386

2226

break;

1387

2227

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

1388

2228

seckey = arg;

1417

2257

argp_error(state, "Bad retry interval");

1418

2258

}

1419

2259

break;

2260

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

2261

hookdir = arg;

2262

break;

1420

2263

/*

1421

2264

* These reproduce what we would get without ARGP_NO_HELP

1422

2265

*/

1428

2271

argp_state_help(state, state->out_stream,

1429

2272

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1430

2273

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

1431

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

2274

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

1432

2275

exit(argp_err_exit_status);

1433

2276

break;

1434

2277

default:

1457

2300

goto end;

1458

2301

}

1459

2302

}

1460

2303

1461

2304

{

1462

2305

/* Work around Debian bug #633582:

1463

2306

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

2307

2308

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2312

perror_plus("Failed to raise privileges");

2313

} else {

2314

struct stat st;

2315

2316

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

2317

int seckey_fd = open(seckey, O_RDONLY);

2318

if(seckey_fd == -1){

2319

perror_plus("open");

2320

} else {

2321

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

2322

if(ret == -1){

2323

perror_plus("fstat");

2324

} else {

2325

if(S_ISREG(st.st_mode)

2326

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

2327

ret = fchown(seckey_fd, uid, gid);

2328

if(ret == -1){

2329

perror_plus("fchown");

2330

}

2331

}

2332

}

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

2334

}

2335

}

2336

2337

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

2338

int pubkey_fd = open(pubkey, O_RDONLY);

2339

if(pubkey_fd == -1){

2340

perror_plus("open");

2341

} else {

2342

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

2343

if(ret == -1){

2344

perror_plus("fstat");

2345

} else {

2346

if(S_ISREG(st.st_mode)

2347

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

2348

ret = fchown(pubkey_fd, uid, gid);

2349

if(ret == -1){

2350

perror_plus("fchown");

2351

}

2352

}

2353

}

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2355

}

2356

}

2357

2358

/* Lower privileges */

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2362

perror_plus("Failed to lower privileges");

2363

}

2364

}

2365

}

2366

2367

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

2368

{

2369

char *interface = NULL;

2370

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

2371

interface))){

2372

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

2373

and if_nametoindex(interface) == 0){

2374

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

2375

fprintf_plus(stderr, "Not using nonexisting interface"

2376

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

2377

}

2378

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

2379

interface = NULL;

2380

}

2381

}

2382

}

2383

2384

/* Run network hooks */

2385

{

2386

if(mc.interfaces != NULL){

2387

interfaces_hooks = malloc(mc.interfaces_size);

2388

if(interfaces_hooks == NULL){

2389

perror_plus("malloc");

2390

goto end;

2391

}

2392

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

2393

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

2394

}

2395

run_network_hooks("start", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

1519

2397

}

1520

2398

1521

2399

if(not debug){

1522

2400

avahi_set_log_function(empty_log);

1523

2401

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

1549

2402

1550

2403

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

1551

2404

from the signal handler */

1552

2405

/* Initialize the pseudo-RNG for Avahi */

1553

2406

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

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

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

2407

simple_poll = avahi_simple_poll_new();

2408

if(simple_poll == NULL){

2409

fprintf_plus(stderr,

2410

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

1557

2411

exitcode = EX_UNAVAILABLE;

1558

2412

goto end;

1559

2413

}

1621

2475

}

1622

2476

}

1623

2477

1624

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

2478

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

2479

if(mc.interfaces == NULL){

2480

struct dirent **direntries = NULL;

2481

/* Look for any good interfaces */

2482

ret = scandir(sys_class_net, &direntries, good_interface,

2483

alphasort);

2484

if(ret >= 1){

2485

/* Add all found interfaces to interfaces list */

2486

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

2487

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

2488

direntries[i]->d_name);

2489

if(ret_errno != 0){

2490

errno = ret_errno;

2491

perror_plus("argz_add");

2492

free(direntries[i]);

2493

continue;

2494

}

2495

if(debug){

2496

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

2497

direntries[i]->d_name);

2498

}

2499

free(direntries[i]);

2500

}

2501

free(direntries);

2502

} else {

2503

if(ret == 0){

2504

free(direntries);

2505

}

2506

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

2507

exitcode = EXIT_FAILURE;

2508

goto end;

2509

}

2510

}

2511

2512

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

2513

{

2514

char *interface = NULL;

2515

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

2516

interface))){

2517

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

2518

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

2519

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

2520

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

2521

interface);

2522

interface = NULL;

2523

while((interface = argz_next(mc.interfaces,

2524

mc.interfaces_size, interface))){

2525

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

2526

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

2527

interface);

2528

interface = NULL;

1709

2529

}

1710

2530

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

2531

break;

1729

2532

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

2533

bool interface_was_up = interface_is_up(interface);

2534

errno = bring_up_interface(interface, delay);

2535

if(not interface_was_up){

2536

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2538

} else {

2539

errno = argz_add(&interfaces_to_take_down,

2540

&interfaces_to_take_down_size,

2541

interface);

2542

if(errno != 0){

2543

perror_plus("argz_add");

2544

}

2545

}

2546

}

2547

}

2548

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

2549

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

2550

}

2551

}

2552

2553

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

2554

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

2555

if(debug){

2556

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

2557

mc.interfaces);

2558

}

2559

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

1767

2560

}

1768

2561

1769

2562

if(quit_now){

1770

2563

goto end;

1771

2564

}

1772

2565

1773

ret = init_gnutls_global(pubkey, seckey);

2566

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

1774

2567

if(ret == -1){

1775

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

2568

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

1776

2569

exitcode = EX_UNAVAILABLE;

1777

2570

goto end;

1778

2571

} else {

1783

2576

goto end;

1784

2577

}

1785

2578

1786

if(mkdtemp(tempdir) == NULL){

2579

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

2580

tempdir = mkdtemp(run_tempdir);

2581

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

2582

if(debug){

2583

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

2584

run_tempdir, old_tempdir);

2585

}

2586

tempdir = mkdtemp(old_tempdir);

2587

}

2588

if(tempdir == NULL){

1787

2589

perror_plus("mkdtemp");

1788

2590

goto end;

1789

2591

}

1790

tempdir_created = true;

1791

2592

1792

2593

if(quit_now){

1793

2594

goto end;

1794

2595

}

1795

2596

1796

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

1797

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

2597

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

2598

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

1798

2599

exitcode = EX_UNAVAILABLE;

1799

2600

goto end;

1800

2601

} else {

1809

2610

/* Connect directly, do not use Zeroconf */

1810

2611

/* (Mainly meant for debugging) */

1811

2612

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

2613

1812

2614

if(address == NULL){

1813

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

2615

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

1814

2616

exitcode = EX_USAGE;

1815

2617

goto end;

1816

2618

}

1819

2621

goto end;

1820

2622

}

1821

2623

1822

uint16_t port;

2624

in_port_t port;

1823

2625

errno = 0;

1824

2626

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

1825

2627

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2628

or tmpmax != (in_port_t)tmpmax){

2629

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

1828

2630

exitcode = EX_USAGE;

1829

2631

goto end;

1830

2632

}

1831

2633

1832

2634

if(quit_now){

1833

2635

goto end;

1834

2636

}

1835

2637

1836

port = (uint16_t)tmpmax;

2638

port = (in_port_t)tmpmax;

1837

2639

*address = '\0';

1838

2640

/* Colon in address indicates IPv6 */

1839

2641

int af;

1855

2657

}

1856

2658

1857

2659

while(not quit_now){

1858

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

2660

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

2661

&mc);

1859

2662

if(quit_now or ret == 0){

1860

2663

break;

1861

2664

}

1862

2665

if(debug){

1863

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

1864

(int)retry_interval);

2666

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

2667

(int)retry_interval);

1865

2668

}

1866

sleep((int)retry_interval);

2669

sleep((unsigned int)retry_interval);

1867

2670

}

1868

2671

1869

if (not quit_now){

2672

if(not quit_now){

1870

2673

exitcode = EXIT_SUCCESS;

1871

2674

}

1872

2675

1873

2676

goto end;

1874

2677

}

1875

2678

1887

2690

config.publish_domain = 0;

1888

2691

1889

2692

/* Allocate a new server */

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2693

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

1893

2695

1894

2696

/* Free the Avahi configuration data */

1895

2697

avahi_server_config_free(&config);

1897

2699

1898

2700

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

1899

2701

if(mc.server == NULL){

1900

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

1901

avahi_strerror(error));

2702

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

2703

avahi_strerror(ret_errno));

1902

2704

exitcode = EX_UNAVAILABLE;

1903

2705

goto end;

1904

2706

}

1910

2712

/* Create the Avahi service browser */

1911

2713

sb = avahi_s_service_browser_new(mc.server, if_index,

1912

2714

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1913

NULL, 0, browse_callback, NULL);

2715

NULL, 0, browse_callback,

2716

(void *)&mc);

1914

2717

if(sb == NULL){

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2718

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

2719

avahi_strerror(avahi_server_errno(mc.server)));

1917

2720

exitcode = EX_UNAVAILABLE;

1918

2721

goto end;

1919

2722

}

1925

2728

/* Run the main loop */

1926

2729

1927

2730

if(debug){

1928

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

2731

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

1929

2732

}

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2733

2734

ret = avahi_loop_with_timeout(simple_poll,

2735

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

1933

2736

if(debug){

1934

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

1935

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

2737

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

2738

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

1936

2739

}

1937

2740

1938

2741

end:

1939

2742

1940

2743

if(debug){

1941

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

2744

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

1942

2745

}

1943

2746

1944

2747

/* Cleanup things */

2748

free(mc.interfaces);

2749

1945

2750

if(sb != NULL)

1946

2751

avahi_s_service_browser_free(sb);

1947

2752

1948

2753

if(mc.server != NULL)

1949

2754

avahi_server_free(mc.server);

1950

2755

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2756

if(simple_poll != NULL)

2757

avahi_simple_poll_free(simple_poll);

1953

2758

1954

2759

if(gnutls_initialized){

1955

2760

gnutls_certificate_free_credentials(mc.cred);

1960

2765

if(gpgme_initialized){

1961

2766

gpgme_release(mc.ctx);

1962

2767

}

1963

2768

1964

2769

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

1965

2770

has seen */

1966

2771

if(mc.current_server != NULL){

1967

2772

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

1968

2773

while(mc.current_server != NULL){

1969

2774

server *next = mc.current_server->next;

2775

#ifdef __GNUC__

2776

#pragma GCC diagnostic push

2777

#pragma GCC diagnostic ignored "-Wcast-qual"

2778

#endif

2779

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

2780

#ifdef __GNUC__

2781

#pragma GCC diagnostic pop

2782

#endif

1970

2783

free(mc.current_server);

1971

2784

mc.current_server = next;

1972

2785

}

1973

2786

}

1974

2787

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

2788

/* Re-raise privileges */

2789

{

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

2793

perror_plus("Failed to raise privileges");

2794

} else {

2795

2796

/* Run network hooks */

2797

run_network_hooks("stop", interfaces_hooks != NULL ?

2798

interfaces_hooks : "", delay);

2799

2800

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

2801

{

2802

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

2809

perror_plus("Failed to take down interface");

2810

}

2811

}

2812

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

2813

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

2814

" down\n");

2815

}

2816

}

1982

2817

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1992

}

1993

}

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

2818

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

perror_plus("Failed to lower privileges permanently");

2004

2823

}

2005

2824

}

2006

2825

2826

free(interfaces_to_take_down);

2827

free(interfaces_hooks);

2828

2007

2829

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

2008

if(tempdir_created){

2830

if(tempdir != NULL){

2009

2831

struct dirent **direntries = NULL;

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

direntry = direntries[i];

2016

char *fullname = NULL;

2017

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

2018

direntry->d_name);

2019

if(ret < 0){

2020

perror_plus("asprintf");

2021

continue;

2022

}

2023

ret = remove(fullname);

2024

if(ret == -1){

2025

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

2026

strerror(errno));

2027

}

2028

free(fullname);

2832

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

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

2842

notdotentries, alphasort);

2843

#else /* not __GLIBC_PREREQ(2, 15) */

2844

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

2845

alphasort);

2846

#endif /* not __GLIBC_PREREQ(2, 15) */

2847

#else /* not __GLIBC__ */

2848

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

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

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

2853

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2854

if(ret == -1){

2855

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2856

" \"%s\", 0): %s\n", tempdir,

2857

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

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

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

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

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

2869

perror_plus("rmdir");

2870

}

2029

2871

}

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

2036

}

2037

ret = rmdir(tempdir);

2038

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

2039

perror_plus("rmdir");

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

2040

2873

}

2041

2874

}

2042

2875