/mandos/release : revision 237.22.4

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() */

41

42

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

43

stdout, ferror(), remove() */

44

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

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() */

62

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

63

strtoimax() */

64

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

65

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

65

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

66

program_invocation_short_name */

66

67

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

67

68

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

68

69

SIOCSIFFLAGS, if_indextoname(),

72

73

*/

73

74

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

74

75

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

75

setgid(), pause() */

76

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

76

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

77

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

77

78

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

78

79

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

79

80

argp_state, struct argp,

84

85

raise() */

85

86

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

86

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

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

89

WEXITSTATUS(), WTERMSIG() */

90

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

91

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

92

argz_delete(), argz_append(),

93

argz_stringify(), argz_add(),

94

argz_count() */

87

95

88

96

#ifdef __linux__

89

97

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

107

115

init_gnutls_session(),

108

116

GNUTLS_* */

109

117

#include <gnutls/openpgp.h>

110

/* gnutls_certificate_set_openpgp_key_file(),

111

GNUTLS_OPENPGP_FMT_BASE64 */

118

/* gnutls_certificate_set_openpgp_key_file(),

119

GNUTLS_OPENPGP_FMT_BASE64 */

112

120

113

121

/* GPGME */

114

122

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

122

130

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

123

131

#define SECKEY "seckey.txt"

124

132

#define PUBKEY "pubkey.txt"

133

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

125

134

126

135

bool debug = false;

127

136

static const char mandos_protocol_version[] = "1";

128

137

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

129

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

138

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

130

139

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

131

140

char *connect_to = NULL;

141

const char *hookdir = HOOKDIR;

142

uid_t uid = 65534;

143

gid_t gid = 65534;

144

145

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

146

typedef struct server{

147

const char *ip;

148

uint16_t port;

149

AvahiIfIndex if_index;

150

int af;

151

struct timespec last_seen;

152

struct server *next;

153

struct server *prev;

154

} server;

132

155

133

156

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

134

157

typedef struct {

139

162

gnutls_dh_params_t dh_params;

140

163

const char *priority;

141

164

gpgme_ctx_t ctx;

165

server *current_server;

142

166

} mandos_context;

143

167

144

168

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

145

169

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

146

170

.dh_bits = 1024, .priority = "SECURE256"

147

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

171

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

172

.current_server = NULL };

148

173

149

174

sig_atomic_t quit_now = 0;

150

175

int signal_received = 0;

151

176

177

/* Function to use when printing errors */

178

void perror_plus(const char *print_text){

179

int e = errno;

180

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

181

program_invocation_short_name);

182

errno = e;

183

perror(print_text);

184

}

185

186

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

187

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

188

va_list ap;

189

va_start (ap, format);

190

191

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

192

program_invocation_short_name));

193

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

194

}

195

152

196

/*

153

197

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

154

198

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

155

199

* "buffer_length" is how much is already used.

156

200

*/

157

201

size_t incbuffer(char **buffer, size_t buffer_length,

158

size_t buffer_capacity){

202

size_t buffer_capacity){

159

203

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

204

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

161

205

if(buffer == NULL){

166

210

return buffer_capacity;

167

211

}

168

212

213

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

214

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

215

int af){

216

int ret;

217

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

218

if(new_server == NULL){

219

perror_plus("malloc");

220

return false;

221

}

222

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

223

.port = port,

224

.if_index = if_index,

225

.af = af };

226

if(new_server->ip == NULL){

227

perror_plus("strdup");

228

return false;

229

}

230

/* Special case of first server */

231

if (mc.current_server == NULL){

232

new_server->next = new_server;

233

new_server->prev = new_server;

234

mc.current_server = new_server;

235

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

236

} else {

237

new_server->next = mc.current_server;

238

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

239

new_server->prev->next = new_server;

240

mc.current_server->prev = new_server;

241

}

242

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

243

if(ret == -1){

244

perror_plus("clock_gettime");

245

return false;

246

}

247

return true;

248

}

249

169

250

/*

170

251

* Initialize GPGME.

171

252

*/

172

static bool init_gpgme(const char *seckey,

173

const char *pubkey, const char *tempdir){

253

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

254

const char *tempdir){

174

255

gpgme_error_t rc;

175

256

gpgme_engine_info_t engine_info;

176

257

185

266

186

267

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

187

268

if(fd == -1){

188

perror("open");

269

perror_plus("open");

189

270

return false;

190

271

}

191

272

192

273

rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

274

if(rc != GPG_ERR_NO_ERROR){

194

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

195

gpgme_strsource(rc), gpgme_strerror(rc));

275

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

276

gpgme_strsource(rc), gpgme_strerror(rc));

196

277

return false;

197

278

}

198

279

199

280

rc = gpgme_op_import(mc.ctx, pgp_data);

200

281

if(rc != GPG_ERR_NO_ERROR){

201

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

202

gpgme_strsource(rc), gpgme_strerror(rc));

282

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

283

gpgme_strsource(rc), gpgme_strerror(rc));

203

284

return false;

204

285

}

205

286

206

287

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

207

288

if(ret == -1){

208

perror("close");

289

perror_plus("close");

209

290

}

210

291

gpgme_data_release(pgp_data);

211

292

return true;

212

293

}

213

294

214

295

if(debug){

215

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

296

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

216

297

}

217

298

218

299

/* Init GPGME */

219

300

gpgme_check_version(NULL);

220

301

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

221

302

if(rc != GPG_ERR_NO_ERROR){

222

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

223

gpgme_strsource(rc), gpgme_strerror(rc));

303

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

304

gpgme_strsource(rc), gpgme_strerror(rc));

224

305

return false;

225

306

}

226

307

227

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

308

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

228

309

rc = gpgme_get_engine_info(&engine_info);

229

310

if(rc != GPG_ERR_NO_ERROR){

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

311

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

312

gpgme_strsource(rc), gpgme_strerror(rc));

232

313

return false;

233

314

}

234

315

while(engine_info != NULL){

240

321

engine_info = engine_info->next;

241

322

}

242

323

if(engine_info == NULL){

243

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

324

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

325

tempdir);

244

326

return false;

245

327

}

246

328

247

329

/* Create new GPGME "context" */

248

330

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

249

331

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

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

334

gpgme_strerror(rc));

252

335

return false;

253

336

}

254

337

273

356

ssize_t plaintext_length = 0;

274

357

275

358

if(debug){

276

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

359

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

277

360

}

278

361

279

362

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

280

363

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

364

0);

282

365

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

366

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

367

gpgme_strsource(rc), gpgme_strerror(rc));

285

368

return -1;

286

369

}

287

370

288

371

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

289

372

rc = gpgme_data_new(&dh_plain);

290

373

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

374

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

375

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

376

gpgme_strsource(rc), gpgme_strerror(rc));

293

377

gpgme_data_release(dh_crypto);

294

378

return -1;

295

379

}

298

382

data buffer */

299

383

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

300

384

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

385

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

386

gpgme_strsource(rc), gpgme_strerror(rc));

303

387

plaintext_length = -1;

304

388

if(debug){

305

389

gpgme_decrypt_result_t result;

306

390

result = gpgme_op_decrypt_result(mc.ctx);

307

391

if(result == NULL){

308

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

392

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

309

393

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

394

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

395

result->unsupported_algorithm);

396

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

397

result->wrong_key_usage);

314

398

if(result->file_name != NULL){

315

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

399

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

316

400

}

317

401

gpgme_recipient_t recipient;

318

402

recipient = result->recipients;

319

403

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

404

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

405

gpgme_pubkey_algo_name

406

(recipient->pubkey_algo));

407

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

408

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

409

recipient->status == GPG_ERR_NO_SECKEY

410

? "No" : "Yes");

326

411

recipient = recipient->next;

327

412

}

328

413

}

331

416

}

332

417

333

418

if(debug){

334

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

419

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

335

420

}

336

421

337

422

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

338

423

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

339

perror("gpgme_data_seek");

424

perror_plus("gpgme_data_seek");

340

425

plaintext_length = -1;

341

426

goto decrypt_end;

342

427

}

344

429

*plaintext = NULL;

345

430

while(true){

346

431

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

432

(size_t)plaintext_length,

433

plaintext_capacity);

349

434

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

435

perror_plus("incbuffer");

436

plaintext_length = -1;

437

goto decrypt_end;

353

438

}

354

439

355

440

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

445

break;

361

446

}

362

447

if(ret < 0){

363

perror("gpgme_data_read");

448

perror_plus("gpgme_data_read");

364

449

plaintext_length = -1;

365

450

goto decrypt_end;

366

451

}

368

453

}

369

454

370

455

if(debug){

371

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

456

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

372

457

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

373

458

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

374

459

}

396

481

/* GnuTLS log function callback */

397

482

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

398

483

const char* string){

399

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

484

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

400

485

}

401

486

402

487

static int init_gnutls_global(const char *pubkeyfilename,

404

489

int ret;

405

490

406

491

if(debug){

407

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

492

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

408

493

}

409

494

410

495

ret = gnutls_global_init();

411

496

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

497

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

498

safer_gnutls_strerror(ret));

414

499

return -1;

415

500

}

416

501

423

508

}

424

509

425

510

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

511

ret = gnutls_certificate_allocate_credentials(&mc.cred);

427

512

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

513

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

514

safer_gnutls_strerror(ret));

433

515

gnutls_global_deinit();

434

516

return -1;

435

517

}

436

518

437

519

if(debug){

438

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

439

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

440

seckeyfilename);

520

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

521

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

522

pubkeyfilename,

523

seckeyfilename);

441

524

}

442

525

443

526

ret = gnutls_certificate_set_openpgp_key_file

444

527

(mc.cred, pubkeyfilename, seckeyfilename,

445

528

GNUTLS_OPENPGP_FMT_BASE64);

446

529

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

530

fprintf_plus(stderr,

531

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

532

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

533

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

534

safer_gnutls_strerror(ret));

452

535

goto globalfail;

453

536

}

454

537

455

538

/* GnuTLS server initialization */

456

539

ret = gnutls_dh_params_init(&mc.dh_params);

457

540

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

541

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

542

" initialization: %s\n",

543

safer_gnutls_strerror(ret));

460

544

goto globalfail;

461

545

}

462

546

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

463

547

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

548

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

549

safer_gnutls_strerror(ret));

466

550

goto globalfail;

467

551

}

468

552

488

572

}

489

573

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

490

574

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

575

fprintf_plus(stderr,

576

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

577

safer_gnutls_strerror(ret));

493

578

}

494

579

495

580

{

502

587

}

503

588

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

504

589

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

590

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

591

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

592

safer_gnutls_strerror(ret));

508

593

gnutls_deinit(*session);

509

594

return -1;

510

595

}

519

604

}

520

605

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

521

606

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

607

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

608

safer_gnutls_strerror(ret));

524

609

gnutls_deinit(*session);

525

610

return -1;

526

611

}

571

656

pf = PF_INET;

572

657

break;

573

658

default:

574

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

659

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

575

660

errno = EINVAL;

576

661

return -1;

577

662

}

582

667

}

583

668

584

669

if(debug){

585

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

586

"\n", ip, port);

670

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

671

PRIu16 "\n", ip, port);

587

672

}

588

673

589

674

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

675

if(tcp_sd < 0){

591

676

int e = errno;

592

perror("socket");

677

perror_plus("socket");

593

678

errno = e;

594

679

goto mandos_end;

595

680

}

609

694

}

610

695

if(ret < 0 ){

611

696

int e = errno;

612

perror("inet_pton");

697

perror_plus("inet_pton");

613

698

errno = e;

614

699

goto mandos_end;

615

700

}

616

701

if(ret == 0){

617

702

int e = errno;

618

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

703

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

619

704

errno = e;

620

705

goto mandos_end;

621

706

}

626

711

627

712

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

713

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

629

-Wunreachable-code*/

714

-Wunreachable-code*/

630

715

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

716

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

717

" incomplete without a network interface\n");

633

718

errno = EINVAL;

634

719

goto mandos_end;

635

720

}

651

736

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

652

737

char interface[IF_NAMESIZE];

653

738

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

654

perror("if_indextoname");

739

perror_plus("if_indextoname");

655

740

} else {

656

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

657

ip, interface, port);

741

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

742

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

658

743

}

659

744

} else {

660

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

661

port);

745

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

746

ip, port);

662

747

}

663

748

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

749

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

671

756

sizeof(addrstr));

672

757

}

673

758

if(pcret == NULL){

674

perror("inet_ntop");

759

perror_plus("inet_ntop");

675

760

} else {

676

761

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

677

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

762

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

678

763

}

679

764

}

680

765

}

692

777

if(ret < 0){

693

778

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

694

779

int e = errno;

695

perror("connect");

780

perror_plus("connect");

696

781

errno = e;

697

782

}

698

783

goto mandos_end;

708

793

while(true){

709

794

size_t out_size = strlen(out);

710

795

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

711

out_size - written));

796

out_size - written));

712

797

if(ret == -1){

713

798

int e = errno;

714

perror("write");

799

perror_plus("write");

715

800

errno = e;

716

801

goto mandos_end;

717

802

}

734

819

}

735

820

736

821

if(debug){

737

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

822

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

738

823

}

739

824

740

825

if(quit_now){

742

827

goto mandos_end;

743

828

}

744

829

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

830

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

831

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

832

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

833

gnutls_transport_set_ptr(session,

834

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

835

747

836

if(quit_now){

748

837

errno = EINTR;

759

848

760

849

if(ret != GNUTLS_E_SUCCESS){

761

850

if(debug){

762

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

851

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

763

852

gnutls_perror(ret);

764

853

}

765

854

errno = EPROTO;

769

858

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

770

859

771

860

if(debug){

772

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

773

ip);

861

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

862

" %s\n", ip);

774

863

}

775

864

776

865

while(true){

781

870

}

782

871

783

872

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

873

buffer_capacity);

785

874

if(buffer_capacity == 0){

786

875

int e = errno;

787

perror("incbuffer");

876

perror_plus("incbuffer");

788

877

errno = e;

789

878

goto mandos_end;

790

879

}

814

903

}

815

904

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

816

905

if(ret < 0){

817

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

906

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

907

"***\n");

818

908

gnutls_perror(ret);

819

909

errno = EPROTO;

820

910

goto mandos_end;

821

911

}

822

912

break;

823

913

default:

824

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

825

" encrypted session with Mandos server\n");

914

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

915

" encrypted session with Mandos server\n");

826

916

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

917

errno = EIO;

828

918

goto mandos_end;

833

923

}

834

924

835

925

if(debug){

836

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

926

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

837

927

}

838

928

839

929

if(quit_now){

851

941

852

942

if(buffer_length > 0){

853

943

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

944

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

856

945

&decrypted_buffer);

857

946

if(decrypted_buffer_size >= 0){

858

947

869

958

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

870

959

int e = errno;

871

960

if(debug){

872

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

873

strerror(errno));

961

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

962

strerror(errno));

874

963

}

875

964

errno = e;

876

965

goto mandos_end;

895

984

if(e == 0){

896

985

e = errno;

897

986

}

898

perror("close");

987

perror_plus("close");

899

988

}

900

989

gnutls_deinit(session);

990

errno = e;

901

991

if(quit_now){

902

e = EINTR;

992

errno = EINTR;

903

993

retval = -1;

904

994

}

905

errno = e;

906

995

}

907

996

return retval;

908

997

}

933

1022

switch(event){

934

1023

default:

935

1024

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1025

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

1026

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

1027

domain,

1028

avahi_strerror(avahi_server_errno(mc.server)));

939

1029

break;

940

1030

941

1031

case AVAHI_RESOLVER_FOUND:

943

1033

char ip[AVAHI_ADDRESS_STR_MAX];

944

1034

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

945

1035

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1036

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

1037

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

1038

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

949

1039

}

950

1040

int ret = start_mandos_communication(ip, port, interface,

951

1041

avahi_proto_to_af(proto));

952

1042

if(ret == 0){

953

1043

avahi_simple_poll_quit(mc.simple_poll);

1044

} else {

1045

if(not add_server(ip, port, interface,

1046

avahi_proto_to_af(proto))){

1047

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

1048

" list\n", name);

1049

}

954

1050

}

955

1051

}

956

1052

}

980

1076

default:

981

1077

case AVAHI_BROWSER_FAILURE:

982

1078

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

1079

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

985

1081

avahi_simple_poll_quit(mc.simple_poll);

986

1082

return;

987

1083

994

1090

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

995

1091

name, type, domain, protocol, 0,

996

1092

resolve_callback, NULL) == NULL)

997

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

998

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

1093

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

1094

" %s\n", name,

1095

avahi_strerror(avahi_server_errno(mc.server)));

999

1096

break;

1000

1097

1001

1098

case AVAHI_BROWSER_REMOVE:

1004

1101

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1102

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1103

if(debug){

1007

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

1104

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

1105

" searching...\n");

1008

1106

}

1009

1107

break;

1010

1108

}

1011

1109

}

1012

1110

1013

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

1111

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

1014

1112

static void handle_sigterm(int sig){

1015

1113

if(quit_now){

1016

1114

return;

1018

1116

quit_now = 1;

1019

1117

signal_received = sig;

1020

1118

int old_errno = errno;

1119

/* set main loop to exit */

1021

1120

if(mc.simple_poll != NULL){

1022

1121

avahi_simple_poll_quit(mc.simple_poll);

1023

1122

}

1024

1123

errno = old_errno;

1025

1124

}

1026

1125

1126

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

1127

int ret;

1128

error_t ret_errno;

1129

1130

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

1131

if(s < 0){

1132

ret_errno = errno;

1133

perror_plus("socket");

1134

errno = ret_errno;

1135

return false;

1136

}

1137

strcpy(ifr->ifr_name, ifname);

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1139

if(ret == -1){

1140

if(debug){

1141

ret_errno = errno;

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1144

}

1145

return false;

1146

}

1147

return true;

1148

}

1149

1150

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

1151

1152

/* Reject the loopback device */

1153

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

ifname);

1157

}

1158

return false;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

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

1165

}

1166

return true;

1167

}

1168

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

1169

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

1170

if(debug){

1171

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1172

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

1173

}

1174

return false;

1175

}

1176

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

1177

if(ifr->ifr_flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

ifname);

1181

}

1182

return false;

1183

}

1184

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

}

1189

return true;

1190

}

1191

1027

1192

/*

1028

1193

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

1029

1194

* corresponds to an acceptable network device.

1030

1195

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

1031

1196

*/

1032

1197

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

1198

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

1042

1199

return 0;

1043

1200

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

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

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1201

1202

struct ifreq ifr;

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1208

return 0;

1209

}

1210

1211

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

1212

return 0;

1213

}

1214

return 1;

1215

}

1216

1217

/*

1218

* This function determines if a network interface is up.

1219

*/

1220

bool interface_is_up(const char *interface){

1221

struct ifreq ifr;

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return false;

1228

}

1229

1230

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

1231

}

1232

1233

/*

1234

* This function determines if a network interface is running

1235

*/

1236

bool interface_is_running(const char *interface){

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return false;

1244

}

1245

1246

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

1247

}

1248

1249

int notdotentries(const struct dirent *direntry){

1250

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

1251

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

1252

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

1253

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

1254

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

1255

return 0;

1256

}

1257

return 1;

1258

}

1259

1260

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

1261

int runnable_hook(const struct dirent *direntry){

1262

int ret;

1263

size_t sret;

1264

struct stat st;

1265

1266

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

1267

/* Empty name? */

1268

return 0;

1269

}

1270

1271

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

1272

"abcdefghijklmnopqrstuvwxyz"

1273

"0123456789"

1274

"_-");

1275

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

1276

/* Contains non-allowed characters */

1277

if(debug){

1278

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

1279

direntry->d_name);

1280

}

1281

return 0;

1282

}

1283

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1292

if(ret == -1){

1293

if(debug){

1294

perror_plus("Could not stat hook");

1295

}

1296

return 0;

1297

}

1298

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

1299

/* Not a regular file */

1300

if(debug){

1301

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

1302

direntry->d_name);

1303

}

1304

return 0;

1305

}

1306

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

1307

/* Not executable */

1308

if(debug){

1309

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

1310

direntry->d_name);

1311

}

1312

return 0;

1313

}

1314

if(debug){

1315

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

1316

direntry->d_name);

1317

}

1318

return 1;

1319

}

1320

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1322

int ret;

1323

struct timespec now;

1324

struct timespec waited_time;

1325

intmax_t block_time;

1326

1327

while(true){

1328

if(mc.current_server == NULL){

1329

if (debug){

1330

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

1331

" No timeout!\n");

1332

}

1333

ret = avahi_simple_poll_iterate(s, -1);

1334

} else {

1335

if (debug){

1336

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

1337

" it, or wait\n");

1338

}

1339

/* the current time */

1340

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1341

if(ret == -1){

1342

perror_plus("clock_gettime");

1343

return -1;

1344

}

1345

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

1346

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

1347

waited_time.tv_sec = (now.tv_sec

1348

- mc.current_server->last_seen.tv_sec);

1349

waited_time.tv_nsec = (now.tv_nsec

1350

- mc.current_server->last_seen.tv_nsec);

1351

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

1352

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

1353

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

1354

block_time = ((retry_interval

1355

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

1356

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

1357

1358

if (debug){

1359

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

1360

block_time);

1361

}

1362

1363

if(block_time <= 0){

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1368

if(ret == 0){

1369

avahi_simple_poll_quit(mc.simple_poll);

1370

return 0;

1371

}

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1373

&mc.current_server->last_seen);

1374

if(ret == -1){

1375

perror_plus("clock_gettime");

1376

return -1;

1377

}

1378

mc.current_server = mc.current_server->next;

1379

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

1380

servers, but don't block */

1381

}

1382

1383

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

1384

}

1385

if(ret != 0){

1386

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

1387

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

1388

}

1389

}

1390

}

1391

}

1392

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1445

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

1446

const float delay){

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1452

if(numhooks == -1){

1453

perror_plus("scandir");

1454

} else {

1455

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

1456

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

1457

direntry = direntries[i];

1458

char *fullname = NULL;

1459

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

1460

if(ret < 0){

1461

perror_plus("asprintf");

1462

continue;

1463

}

1464

if(debug){

1465

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

1466

direntry->d_name);

1467

}

1468

pid_t hook_pid = fork();

1469

if(hook_pid == 0){

1470

/* Child */

1471

/* Raise privileges */

1472

raise_privileges_permanently();

1473

/* Set group */

1474

errno = 0;

1475

ret = setgid(0);

1476

if(ret == -1){

1477

perror_plus("setgid");

1478

}

1479

/* Reset supplementary groups */

1480

errno = 0;

1481

ret = setgroups(0, NULL);

1482

if(ret == -1){

1483

perror_plus("setgroups");

1484

}

1485

dup2(devnull, STDIN_FILENO);

1486

close(devnull);

1487

dup2(STDERR_FILENO, STDOUT_FILENO);

1488

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

1489

if(ret == -1){

1490

perror_plus("setenv");

1491

_exit(EX_OSERR);

1492

}

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

char *delaystring;

1509

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

1510

if(ret == -1){

1511

perror_plus("asprintf");

1512

_exit(EX_OSERR);

1513

}

1514

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

1515

if(ret == -1){

1516

free(delaystring);

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

free(delaystring);

1521

if(connect_to != NULL){

1522

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

1523

if(ret == -1){

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1527

}

1528

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

1529

perror_plus("execl");

1530

_exit(EXIT_FAILURE);

1531

}

1532

} else {

1533

int status;

1534

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

1535

perror_plus("waitpid");

1536

free(fullname);

1537

continue;

1538

}

1539

if(WIFEXITED(status)){

1540

if(WEXITSTATUS(status) != 0){

1541

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

1542

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

1543

WEXITSTATUS(status));

1544

free(fullname);

1545

continue;

1546

}

1547

} else if(WIFSIGNALED(status)){

1548

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

1549

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

1550

WTERMSIG(status));

1551

free(fullname);

1552

continue;

1553

} else {

1554

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

1555

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

1556

free(fullname);

1557

continue;

1558

}

1559

}

1560

free(fullname);

1561

if(debug){

1562

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

1563

direntry->d_name);

1564

}

1565

}

1566

close(devnull);

1567

}

1568

return true;

1569

}

1570

1571

error_t bring_up_interface(const char *const interface,

1572

const float delay){

1573

int sd = -1;

1574

error_t old_errno = errno;

1575

error_t ret_errno = 0;

1576

int ret, ret_setflags;

1577

struct ifreq network;

1578

unsigned int if_index = if_nametoindex(interface);

1579

if(if_index == 0){

1580

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

1581

errno = old_errno;

1582

return ENXIO;

1583

}

1584

1585

if(quit_now){

1586

errno = old_errno;

1587

return EINTR;

1588

}

1589

1590

if(not interface_is_up(interface)){

1591

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

1592

ret_errno = errno;

1593

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

1594

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

1595

return ret_errno;

1596

}

1597

network.ifr_flags |= IFF_UP;

1598

1599

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1600

if(sd < 0){

1601

ret_errno = errno;

1602

perror_plus("socket");

1603

errno = old_errno;

1604

return ret_errno;

1605

}

1606

1607

if(quit_now){

1608

close(sd);

1609

errno = old_errno;

1610

return EINTR;

1611

}

1612

1613

if(debug){

1614

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

1615

interface);

1616

}

1617

1618

/* Raise priviliges */

1619

raise_privileges();

1620

1621

#ifdef __linux__

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

int ret_linux = klogctl(8, NULL, 5);

1625

bool restore_loglevel = true;

1626

if(ret_linux == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1629

}

1630

#endif /* __linux__ */

1631

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

1632

ret_errno = errno;

1633

#ifdef __linux__

1634

if(restore_loglevel){

1635

ret_linux = klogctl(7, NULL, 0);

1636

if(ret_linux == -1){

1637

perror_plus("klogctl");

1638

}

1639

}

1640

#endif /* __linux__ */

1641

1642

/* Lower privileges */

1643

lower_privileges();

1644

1645

/* Close the socket */

1646

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

1647

if(ret == -1){

1648

perror_plus("close");

1649

}

1650

1651

if(ret_setflags == -1){

1652

errno = ret_errno;

1653

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1654

errno = old_errno;

1655

return ret_errno;

1656

}

1657

} else if(debug){

1658

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

1659

interface);

1660

}

1661

1662

/* Sleep checking until interface is running.

1663

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

1664

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

1665

if(interface_is_running(interface)){

1070

1666

break;

1071

1667

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

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

1100

if(debug){

1101

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

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

1668

struct timespec sleeptime = { .tv_nsec = 250000000 };

1669

ret = nanosleep(&sleeptime, NULL);

1670

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

1671

perror_plus("nanosleep");

1672

}

1673

}

1674

1675

errno = old_errno;

1676

return 0;

1677

}

1678

1679

error_t take_down_interface(const char *const interface){

1680

int sd = -1;

1681

error_t old_errno = errno;

1682

error_t ret_errno = 0;

1683

int ret, ret_setflags;

1684

struct ifreq network;

1685

unsigned int if_index = if_nametoindex(interface);

1686

if(if_index == 0){

1687

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

1688

errno = old_errno;

1689

return ENXIO;

1690

}

1691

if(interface_is_up(interface)){

1692

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

1693

ret_errno = errno;

1694

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

1695

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

1696

return ret_errno;

1697

}

1698

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

1699

1700

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1701

if(sd < 0){

1702

ret_errno = errno;

1703

perror_plus("socket");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

1708

if(debug){

1709

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

1710

interface);

1711

}

1712

1713

/* Raise priviliges */

1714

raise_privileges();

1715

1716

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

1717

ret_errno = errno;

1718

1719

/* Lower privileges */

1720

lower_privileges();

1721

1722

/* Close the socket */

1723

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

1724

if(ret == -1){

1725

perror_plus("close");

1726

}

1727

1728

if(ret_setflags == -1){

1729

errno = ret_errno;

1730

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1731

errno = old_errno;

1732

return ret_errno;

1733

}

1734

} else if(debug){

1735

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

1736

interface);

1737

}

1738

1739

errno = old_errno;

1740

return 0;

1120

1741

}

1121

1742

1122

1743

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

1123

1744

AvahiSServiceBrowser *sb = NULL;

1124

int error;

1745

error_t ret_errno;

1125

1746

int ret;

1126

1747

intmax_t tmpmax;

1127

1748

char *tmp;

1128

1749

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

1130

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

1133

uid_t uid;

1134

gid_t gid;

1750

char *interfaces = NULL;

1751

size_t interfaces_size = 0;

1752

char *interfaces_to_take_down = NULL;

1753

size_t interfaces_to_take_down_size = 0;

1135

1754

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

1136

1755

bool tempdir_created = false;

1137

1756

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

1757

const char *seckey = PATHDIR "/" SECKEY;

1139

1758

const char *pubkey = PATHDIR "/" PUBKEY;

1759

char *interfaces_hooks = NULL;

1760

size_t interfaces_hooks_size = 0;

1140

1761

1141

1762

bool gnutls_initialized = false;

1142

1763

bool gpgme_initialized = false;

1143

1764

float delay = 2.5f;

1765

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

1766

retrying the same server again */

1144

1767

1145

1768

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1769

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1775

errno = 0;

1153

1776

ret = setgid(gid);

1154

1777

if(ret == -1){

1155

perror("setgid");

1778

perror_plus("setgid");

1156

1779

}

1157

1780

1158

1781

/* Lower user privileges (temporarily) */

1159

1782

errno = 0;

1160

1783

ret = seteuid(uid);

1161

1784

if(ret == -1){

1162

perror("seteuid");

1785

perror_plus("seteuid");

1163

1786

}

1164

1787

1165

1788

if(quit_now){

1200

1823

.arg = "SECONDS",

1201

1824

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

1202

1825

.group = 2 },

1826

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

1827

.arg = "SECONDS",

1828

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

1829

.group = 2 },

1830

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

1831

.arg = "DIR",

1832

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

1833

.group = 2 },

1203

1834

/*

1204

1835

* These reproduce what we would get without ARGP_NO_HELP

1205

1836

*/

1223

1854

connect_to = arg;

1224

1855

break;

1225

1856

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

1226

interface = arg;

1857

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1858

(int)',');

1859

if(ret_errno != 0){

1860

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

1861

}

1227

1862

break;

1228

1863

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

1229

1864

seckey = arg;

1249

1884

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

1250

1885

argp_error(state, "Bad delay");

1251

1886

}

1887

case 132: /* --retry */

1888

errno = 0;

1889

retry_interval = strtod(arg, &tmp);

1890

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

1891

or (retry_interval * 1000) > INT_MAX

1892

or retry_interval < 0){

1893

argp_error(state, "Bad retry interval");

1894

}

1895

break;

1896

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

1897

hookdir = arg;

1252

1898

break;

1253

1899

/*

1254

1900

* These reproduce what we would get without ARGP_NO_HELP

1261

1907

argp_state_help(state, state->out_stream,

1262

1908

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

1909

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

1264

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

1910

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

1265

1911

exit(argp_err_exit_status);

1266

1912

break;

1267

1913

default:

1282

1928

case ENOMEM:

1283

1929

default:

1284

1930

errno = ret;

1285

perror("argp_parse");

1931

perror_plus("argp_parse");

1286

1932

exitcode = EX_OSERR;

1287

1933

goto end;

1288

1934

case EINVAL:

1290

1936

goto end;

1291

1937

}

1292

1938

}

1939

1940

{

1941

/* Work around Debian bug #633582:

1942

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

1943

1944

/* Re-raise priviliges */

1945

if(raise_privileges() == 0){

1946

struct stat st;

1947

1948

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

1949

int seckey_fd = open(seckey, O_RDONLY);

1950

if(seckey_fd == -1){

1951

perror_plus("open");

1952

} else {

1953

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

1954

if(ret == -1){

1955

perror_plus("fstat");

1956

} else {

1957

if(S_ISREG(st.st_mode)

1958

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

1959

ret = fchown(seckey_fd, uid, gid);

1960

if(ret == -1){

1961

perror_plus("fchown");

1962

}

1963

}

1964

}

1965

TEMP_FAILURE_RETRY(close(seckey_fd));

1966

}

1967

}

1968

1969

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

1970

int pubkey_fd = open(pubkey, O_RDONLY);

1971

if(pubkey_fd == -1){

1972

perror_plus("open");

1973

} else {

1974

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

1975

if(ret == -1){

1976

perror_plus("fstat");

1977

} else {

1978

if(S_ISREG(st.st_mode)

1979

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

1980

ret = fchown(pubkey_fd, uid, gid);

1981

if(ret == -1){

1982

perror_plus("fchown");

1983

}

1984

}

1985

}

1986

TEMP_FAILURE_RETRY(close(pubkey_fd));

1987

}

1988

}

1989

1990

/* Lower privileges */

1991

errno = 0;

1992

ret = seteuid(uid);

1993

if(ret == -1){

1994

perror_plus("seteuid");

1995

}

1996

}

1997

}

1998

1999

/* Remove empty interface names */

2000

{

2001

char *interface = NULL;

2002

while((interface = argz_next(interfaces, interfaces_size,

2003

interface))){

2004

if(if_nametoindex(interface) == 0){

2005

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2006

fprintf_plus(stderr, "Not using nonexisting interface"

2007

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

2008

}

2009

argz_delete(&interfaces, &interfaces_size, interface);

2010

interface = NULL;

2011

}

2012

}

2013

}

2014

2015

/* Run network hooks */

2016

{

2017

ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,

2018

interfaces, interfaces_size);

2019

if(ret_errno != 0){

2020

errno = ret_errno;

2021

perror_plus("argz_append");

2022

goto end;

2023

}

2024

argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');

2025

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

2026

goto end;

2027

}

2028

}

1293

2029

1294

2030

if(not debug){

1295

2031

avahi_set_log_function(empty_log);

1296

2032

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1322

2033

1323

2034

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

1324

2035

from the signal handler */

1326

2037

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

1327

2038

mc.simple_poll = avahi_simple_poll_new();

1328

2039

if(mc.simple_poll == NULL){

1329

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

2040

fprintf_plus(stderr,

2041

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

1330

2042

exitcode = EX_UNAVAILABLE;

1331

2043

goto end;

1332

2044

}

1334

2046

sigemptyset(&sigterm_action.sa_mask);

1335

2047

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

1336

2048

if(ret == -1){

1337

perror("sigaddset");

2049

perror_plus("sigaddset");

1338

2050

exitcode = EX_OSERR;

1339

2051

goto end;

1340

2052

}

1341

2053

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

1342

2054

if(ret == -1){

1343

perror("sigaddset");

2055

perror_plus("sigaddset");

1344

2056

exitcode = EX_OSERR;

1345

2057

goto end;

1346

2058

}

1347

2059

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

1348

2060

if(ret == -1){

1349

perror("sigaddset");

2061

perror_plus("sigaddset");

1350

2062

exitcode = EX_OSERR;

1351

2063

goto end;

1352

2064

}

1356

2068

*/

1357

2069

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

1358

2070

if(ret == -1){

1359

perror("sigaction");

2071

perror_plus("sigaction");

1360

2072

return EX_OSERR;

1361

2073

}

1362

2074

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

2075

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

1364

2076

if(ret == -1){

1365

perror("sigaction");

2077

perror_plus("sigaction");

1366

2078

exitcode = EX_OSERR;

1367

2079

goto end;

1368

2080

}

1369

2081

}

1370

2082

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

1371

2083

if(ret == -1){

1372

perror("sigaction");

2084

perror_plus("sigaction");

1373

2085

return EX_OSERR;

1374

2086

}

1375

2087

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

2088

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

1377

2089

if(ret == -1){

1378

perror("sigaction");

2090

perror_plus("sigaction");

1379

2091

exitcode = EX_OSERR;

1380

2092

goto end;

1381

2093

}

1382

2094

}

1383

2095

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

1384

2096

if(ret == -1){

1385

perror("sigaction");

2097

perror_plus("sigaction");

1386

2098

return EX_OSERR;

1387

2099

}

1388

2100

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

2101

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

1390

2102

if(ret == -1){

1391

perror("sigaction");

2103

perror_plus("sigaction");

1392

2104

exitcode = EX_OSERR;

1393

2105

goto end;

1394

2106

}

1395

2107

}

1396

2108

1397

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1417

#ifdef __linux__

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

1420

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

if(ret == -1){

1423

restore_loglevel = false;

1424

perror("klogctl");

1425

}

1426

#endif /* __linux__ */

1427

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

if(sd < 0){

1430

perror("socket");

1431

exitcode = EX_OSERR;

1432

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1446

goto end;

1447

}

1448

strcpy(network.ifr_name, interface);

1449

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

1450

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1452

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1467

goto end;

1468

}

1469

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

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

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

1473

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1477

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

1482

}

1483

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1491

goto end;

1492

}

1493

}

1494

/* sleep checking until interface is running */

1495

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

1496

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

1497

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1499

} else if(network.ifr_flags & IFF_RUNNING){

1500

break;

1501

}

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

ret = nanosleep(&sleeptime, NULL);

1504

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

1505

perror("nanosleep");

1506

}

1507

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1514

}

1515

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

2109

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

2110

if(interfaces == NULL){

2111

struct dirent **direntries;

2112

/* Look for any good interfaces */

2113

ret = scandir(sys_class_net, &direntries, good_interface,

2114

alphasort);

2115

if(ret >= 1){

2116

/* Add all found interfaces to interfaces list */

2117

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

2118

ret_errno = argz_add(&interfaces, &interfaces_size,

2119

direntries[i]->d_name);

2120

if(ret_errno != 0){

2121

perror_plus("argz_add");

2122

continue;

2123

}

2124

if(debug){

2125

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

2126

direntries[i]->d_name);

2127

}

2128

}

2129

free(direntries);

1532

2130

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

2131

free(direntries);

2132

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

2133

exitcode = EXIT_FAILURE;

2134

goto end;

2135

}

2136

}

2137

2138

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

2139

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

2140

if(debug){

2141

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

2142

interfaces);

2143

}

2144

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2145

}

2146

2147

/* Bring up interfaces which are down */

2148

if(not (argz_count(interfaces, interfaces_size) == 1

2149

and strcmp(interfaces, "none") == 0)){

2150

char *interface = NULL;

2151

while((interface = argz_next(interfaces, interfaces_size,

2152

interface))){

2153

bool interface_was_up = interface_is_up(interface);

2154

ret = bring_up_interface(interface, delay);

2155

if(not interface_was_up){

2156

if(ret != 0){

2157

errno = ret;

2158

perror_plus("Failed to bring up interface");

2159

} else {

2160

ret_errno = argz_add(&interfaces_to_take_down,

2161

&interfaces_to_take_down_size,

2162

interface);

2163

}

1537

2164

}

1538

2165

}

2166

free(interfaces);

2167

interfaces = NULL;

2168

interfaces_size = 0;

2169

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

2170

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

2171

}

1539

2172

}

1540

2173

1541

2174

if(quit_now){

1544

2177

1545

2178

ret = init_gnutls_global(pubkey, seckey);

1546

2179

if(ret == -1){

1547

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

2180

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

1548

2181

exitcode = EX_UNAVAILABLE;

1549

2182

goto end;

1550

2183

} else {

1555

2188

goto end;

1556

2189

}

1557

2190

2191

if(mkdtemp(tempdir) == NULL){

2192

perror_plus("mkdtemp");

2193

goto end;

2194

}

1558

2195

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

1562

goto end;

1563

}

1564

2196

1565

2197

if(quit_now){

1566

2198

goto end;

1567

2199

}

1568

2200

1569

2201

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

1570

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

2202

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

1571

2203

exitcode = EX_UNAVAILABLE;

1572

2204

goto end;

1573

2205

} else {

1582

2214

/* Connect directly, do not use Zeroconf */

1583

2215

/* (Mainly meant for debugging) */

1584

2216

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

2217

1585

2218

if(address == NULL){

1586

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

2219

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

1587

2220

exitcode = EX_USAGE;

1588

2221

goto end;

1589

2222

}

1597

2230

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

1598

2231

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

1599

2232

or tmpmax != (uint16_t)tmpmax){

1600

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

2233

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

1601

2234

exitcode = EX_USAGE;

1602

2235

goto end;

1603

2236

}

1608

2241

1609

2242

port = (uint16_t)tmpmax;

1610

2243

*address = '\0';

1611

address = connect_to;

1612

2244

/* Colon in address indicates IPv6 */

1613

2245

int af;

1614

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

2246

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

1615

2247

af = AF_INET6;

2248

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

2249

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

2250

{

2251

connect_to++;

2252

address[-1] = '\0';

2253

}

1616

2254

} else {

1617

2255

af = AF_INET;

1618

2256

}

2257

address = connect_to;

1619

2258

1620

2259

if(quit_now){

1621

2260

goto end;

1622

2261

}

1623

2262

1624

2263

while(not quit_now){

1625

2264

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

1626

2265

if(quit_now or ret == 0){

1627

2266

break;

1628

2267

}

1629

sleep(15);

1630

};

1631

2268

if(debug){

2269

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

2270

(int)retry_interval);

2271

}

2272

sleep((int)retry_interval);

2273

}

2274

1632

2275

if (not quit_now){

1633

2276

exitcode = EXIT_SUCCESS;

1634

2277

}

1635

2278

1636

2279

goto end;

1637

2280

}

1638

2281

1652

2295

/* Allocate a new server */

1653

2296

mc.server = avahi_server_new(avahi_simple_poll_get

1654

2297

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2298

NULL, &ret_errno);

1656

2299

1657

2300

/* Free the Avahi configuration data */

1658

2301

avahi_server_config_free(&config);

1660

2303

1661

2304

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

1662

2305

if(mc.server == NULL){

1663

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

1664

avahi_strerror(error));

2306

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

2307

avahi_strerror(ret_errno));

1665

2308

exitcode = EX_UNAVAILABLE;

1666

2309

goto end;

1667

2310

}

1675

2318

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

2319

NULL, 0, browse_callback, NULL);

1677

2320

if(sb == NULL){

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2321

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

2322

avahi_strerror(avahi_server_errno(mc.server)));

1680

2323

exitcode = EX_UNAVAILABLE;

1681

2324

goto end;

1682

2325

}

1688

2331

/* Run the main loop */

1689

2332

1690

2333

if(debug){

1691

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

1692

}

1693

1694

avahi_simple_poll_loop(mc.simple_poll);

2334

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

2335

}

2336

2337

ret = avahi_loop_with_timeout(mc.simple_poll,

2338

(int)(retry_interval * 1000));

2339

if(debug){

2340

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

2341

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

2342

}

1695

2343

1696

2344

end:

1697

2345

1698

2346

if(debug){

1699

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

2347

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

1700

2348

}

1701

2349

1702

2350

/* Cleanup things */

1719

2367

gpgme_release(mc.ctx);

1720

2368

}

1721

2369

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

2370

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

2371

has seen */

2372

if(mc.current_server != NULL){

2373

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

2374

while(mc.current_server != NULL){

2375

server *next = mc.current_server->next;

2376

free(mc.current_server);

2377

mc.current_server = next;

1729

2378

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

2379

}

2380

2381

/* Re-raise priviliges */

2382

{

2383

raise_privileges();

2384

2385

/* Run network hooks */

2386

run_network_hooks("stop", interfaces_hooks, delay);

2387

2388

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

2389

{

2390

char *interface = NULL;

2391

while((interface=argz_next(interfaces_to_take_down,

2392

interfaces_to_take_down_size,

2393

interface))){

2394

ret_errno = take_down_interface(interface);

2395

if(ret_errno != 0){

2396

errno = ret_errno;

2397

perror_plus("Failed to take down interface");

1739

2398

}

1740

2399

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

2400

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

2401

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

2402

" down\n");

1750

2403

}

1751

2404

}

2405

2406

lower_privileges_permanently();

1752

2407

}

1753

2408

1754

/* Removes the temp directory used by GPGME */

2409

free(interfaces_to_take_down);

2410

free(interfaces_hooks);

2411

2412

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

1755

2413

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

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

1772

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

1773

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

1774

continue;

1775

}

2414

struct dirent **direntries = NULL;

2415

struct dirent *direntry = NULL;

2416

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

2417

alphasort);

2418

if (numentries > 0){

2419

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

2420

direntry = direntries[i];

1776

2421

char *fullname = NULL;

1777

2422

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

1778

2423

direntry->d_name);

1779

2424

if(ret < 0){

1780

perror("asprintf");

2425

perror_plus("asprintf");

1781

2426

continue;

1782

2427

}

1783

2428

ret = remove(fullname);

1784

2429

if(ret == -1){

1785

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

1786

strerror(errno));

2430

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

2431

strerror(errno));

1787

2432

}

1788

2433

free(fullname);

1789

2434

}

1790

closedir(d);

2435

}

2436

2437

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

2438

free(direntries);

2439

if (numentries == -1){

2440

perror_plus("scandir");

1791

2441

}

1792

2442

ret = rmdir(tempdir);

1793

2443

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

1794

perror("rmdir");

2444

perror_plus("rmdir");

1795

2445

}

1796

2446

}

1797

2447

1802

2452

&old_sigterm_action,

1803

2453

NULL));

1804

2454

if(ret == -1){

1805

perror("sigaction");

2455

perror_plus("sigaction");

1806

2456

}

1807

2457

do {

1808

2458

ret = raise(signal_received);

1809

2459

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

1810

2460

if(ret != 0){

1811

perror("raise");

2461

perror_plus("raise");

1812

2462

abort();

1813

2463

}

1814

2464

TEMP_FAILURE_RETRY(pause());