/mandos/trunk : revision 358

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@recompile.se>.

29

* Contact the authors at <mandos@fukt.bsnet.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, intptr_t */

44

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

45

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

46

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

47

strtof(), abort() */

46

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

47

srand(), strtof() */

48

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

49

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

50

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

53

sockaddr_in6, PF_INET6,

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

56

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

56

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

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,

66

program_invocation_short_name */

67

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

65

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

66

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

68

67

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

69

68

SIOCSIFFLAGS, if_indextoname(),

70

69

if_nametoindex(), IF_NAMESIZE */

72

71

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

73

72

*/

74

73

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

75

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

76

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

77

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

74

getuid(), getgid(), setuid(),

75

setgid() */

76

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

78

77

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

79

78

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

80

79

argp_state, struct argp,

83

82

#include <signal.h> /* sigemptyset(), sigaddset(),

84

83

sigaction(), SIGTERM, sig_atomic_t,

85

84

raise() */

86

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

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

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

89

WEXITSTATUS(), WTERMSIG() */

90

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

91

85

92

86

#ifdef __linux__

93

87

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

111

105

init_gnutls_session(),

112

106

GNUTLS_* */

113

107

#include <gnutls/openpgp.h>

114

/* gnutls_certificate_set_openpgp_key_file(),

115

GNUTLS_OPENPGP_FMT_BASE64 */

108

/* gnutls_certificate_set_openpgp_key_file(),

109

GNUTLS_OPENPGP_FMT_BASE64 */

116

110

117

111

/* GPGME */

118

112

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

126

120

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

127

121

#define SECKEY "seckey.txt"

128

122

#define PUBKEY "pubkey.txt"

129

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

130

123

131

124

bool debug = false;

132

125

static const char mandos_protocol_version[] = "1";

133

126

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

134

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

135

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

136

char *connect_to = NULL;

137

const char *hookdir = HOOKDIR;

138

139

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

140

typedef struct server{

141

const char *ip;

142

uint16_t port;

143

AvahiIfIndex if_index;

144

int af;

145

struct timespec last_seen;

146

struct server *next;

147

struct server *prev;

148

} server;

127

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

149

128

150

129

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

151

130

typedef struct {

156

135

gnutls_dh_params_t dh_params;

157

136

const char *priority;

158

137

gpgme_ctx_t ctx;

159

server *current_server;

160

138

} mandos_context;

161

139

162

140

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

163

141

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

164

142

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

167

168

sig_atomic_t quit_now = 0;

169

int signal_received = 0;

170

171

/* Function to use when printing errors */

172

void perror_plus(const char *print_text){

173

int e = errno;

174

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

175

program_invocation_short_name);

176

errno = e;

177

perror(print_text);

178

}

179

180

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

181

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

182

va_list ap;

183

va_start (ap, format);

184

185

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

186

program_invocation_short_name));

187

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

188

}

143

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

189

144

190

145

/*

191

146

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

193

148

* "buffer_length" is how much is already used.

194

149

*/

195

150

size_t incbuffer(char **buffer, size_t buffer_length,

196

size_t buffer_capacity){

151

size_t buffer_capacity){

197

152

if(buffer_length + BUFFER_SIZE > buffer_capacity){

198

153

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

199

154

if(buffer == NULL){

204

159

return buffer_capacity;

205

160

}

206

161

207

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

208

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

209

int af){

210

int ret;

211

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

212

if(new_server == NULL){

213

perror_plus("malloc");

214

return false;

215

}

216

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

217

.port = port,

218

.if_index = if_index,

219

.af = af };

220

if(new_server->ip == NULL){

221

perror_plus("strdup");

222

return false;

223

}

224

/* Special case of first server */

225

if (mc.current_server == NULL){

226

new_server->next = new_server;

227

new_server->prev = new_server;

228

mc.current_server = new_server;

229

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

230

} else {

231

new_server->next = mc.current_server;

232

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

233

new_server->prev->next = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

240

}

241

return true;

242

}

243

244

162

/*

245

163

* Initialize GPGME.

246

164

*/

247

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

248

const char *tempdir){

165

static bool init_gpgme(const char *seckey,

166

const char *pubkey, const char *tempdir){

167

int ret;

249

168

gpgme_error_t rc;

250

169

gpgme_engine_info_t engine_info;

251

170

254

173

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

255

174

*/

256

175

bool import_key(const char *filename){

257

int ret;

258

176

int fd;

259

177

gpgme_data_t pgp_data;

260

178

261

179

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

262

180

if(fd == -1){

263

perror_plus("open");

181

perror("open");

264

182

return false;

265

183

}

266

184

267

185

rc = gpgme_data_new_from_fd(&pgp_data, fd);

268

186

if(rc != GPG_ERR_NO_ERROR){

269

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

270

gpgme_strsource(rc), gpgme_strerror(rc));

187

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

188

gpgme_strsource(rc), gpgme_strerror(rc));

271

189

return false;

272

190

}

273

191

274

192

rc = gpgme_op_import(mc.ctx, pgp_data);

275

193

if(rc != GPG_ERR_NO_ERROR){

276

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

277

gpgme_strsource(rc), gpgme_strerror(rc));

194

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

195

gpgme_strsource(rc), gpgme_strerror(rc));

278

196

return false;

279

197

}

280

198

281

199

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

282

200

if(ret == -1){

283

perror_plus("close");

201

perror("close");

284

202

}

285

203

gpgme_data_release(pgp_data);

286

204

return true;

287

205

}

288

206

289

207

if(debug){

290

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

208

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

291

209

}

292

210

293

211

/* Init GPGME */

294

212

gpgme_check_version(NULL);

295

213

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

296

214

if(rc != GPG_ERR_NO_ERROR){

297

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

298

gpgme_strsource(rc), gpgme_strerror(rc));

215

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

216

gpgme_strsource(rc), gpgme_strerror(rc));

299

217

return false;

300

218

}

301

219

302

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

220

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

303

221

rc = gpgme_get_engine_info(&engine_info);

304

222

if(rc != GPG_ERR_NO_ERROR){

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

223

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

224

gpgme_strsource(rc), gpgme_strerror(rc));

307

225

return false;

308

226

}

309

227

while(engine_info != NULL){

315

233

engine_info = engine_info->next;

316

234

}

317

235

if(engine_info == NULL){

318

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

319

tempdir);

236

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

320

237

return false;

321

238

}

322

239

323

240

/* Create new GPGME "context" */

324

241

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

325

242

if(rc != GPG_ERR_NO_ERROR){

326

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

327

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

328

gpgme_strerror(rc));

243

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

244

gpgme_strsource(rc), gpgme_strerror(rc));

329

245

return false;

330

246

}

331

247

350

266

ssize_t plaintext_length = 0;

351

267

352

268

if(debug){

353

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

269

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

354

270

}

355

271

356

272

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

357

273

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

358

274

0);

359

275

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

276

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

277

gpgme_strsource(rc), gpgme_strerror(rc));

362

278

return -1;

363

279

}

364

280

365

281

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

366

282

rc = gpgme_data_new(&dh_plain);

367

283

if(rc != GPG_ERR_NO_ERROR){

368

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

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

284

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

285

gpgme_strsource(rc), gpgme_strerror(rc));

371

286

gpgme_data_release(dh_crypto);

372

287

return -1;

373

288

}

376

291

data buffer */

377

292

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

378

293

if(rc != GPG_ERR_NO_ERROR){

379

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

380

gpgme_strsource(rc), gpgme_strerror(rc));

294

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

295

gpgme_strsource(rc), gpgme_strerror(rc));

381

296

plaintext_length = -1;

382

297

if(debug){

383

298

gpgme_decrypt_result_t result;

384

299

result = gpgme_op_decrypt_result(mc.ctx);

385

300

if(result == NULL){

386

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

301

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

387

302

} else {

388

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

389

result->unsupported_algorithm);

390

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

391

result->wrong_key_usage);

303

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

304

result->unsupported_algorithm);

305

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

306

result->wrong_key_usage);

392

307

if(result->file_name != NULL){

393

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

308

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

394

309

}

395

310

gpgme_recipient_t recipient;

396

311

recipient = result->recipients;

397

312

while(recipient != NULL){

398

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

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

402

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

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

313

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

314

gpgme_pubkey_algo_name(recipient->pubkey_algo));

315

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

316

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

317

recipient->status == GPG_ERR_NO_SECKEY

318

? "No" : "Yes");

405

319

recipient = recipient->next;

406

320

}

407

321

}

410

324

}

411

325

412

326

if(debug){

413

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

327

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

414

328

}

415

329

416

330

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

417

331

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

418

perror_plus("gpgme_data_seek");

332

perror("gpgme_data_seek");

419

333

plaintext_length = -1;

420

334

goto decrypt_end;

421

335

}

423

337

*plaintext = NULL;

424

338

while(true){

425

339

plaintext_capacity = incbuffer(plaintext,

426

(size_t)plaintext_length,

427

plaintext_capacity);

340

(size_t)plaintext_length,

341

plaintext_capacity);

428

342

if(plaintext_capacity == 0){

429

perror_plus("incbuffer");

430

plaintext_length = -1;

431

goto decrypt_end;

343

perror("incbuffer");

344

plaintext_length = -1;

345

goto decrypt_end;

432

346

}

433

347

434

348

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

439

353

break;

440

354

}

441

355

if(ret < 0){

442

perror_plus("gpgme_data_read");

356

perror("gpgme_data_read");

443

357

plaintext_length = -1;

444

358

goto decrypt_end;

445

359

}

447

361

}

448

362

449

363

if(debug){

450

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

364

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

451

365

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

452

366

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

453

367

}

475

389

/* GnuTLS log function callback */

476

390

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

477

391

const char* string){

478

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

392

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

479

393

}

480

394

481

395

static int init_gnutls_global(const char *pubkeyfilename,

483

397

int ret;

484

398

485

399

if(debug){

486

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

400

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

487

401

}

488

402

489

403

ret = gnutls_global_init();

490

404

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

405

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

406

safer_gnutls_strerror(ret));

493

407

return -1;

494

408

}

495

409

502

416

}

503

417

504

418

/* OpenPGP credentials */

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

419

gnutls_certificate_allocate_credentials(&mc.cred);

506

420

if(ret != GNUTLS_E_SUCCESS){

507

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

508

safer_gnutls_strerror(ret));

421

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

422

from

423

-Wunreachable-code

424

*/

425

safer_gnutls_strerror(ret));

509

426

gnutls_global_deinit();

510

427

return -1;

511

428

}

512

429

513

430

if(debug){

514

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

515

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

516

pubkeyfilename,

517

seckeyfilename);

431

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

432

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

433

seckeyfilename);

518

434

}

519

435

520

436

ret = gnutls_certificate_set_openpgp_key_file

521

437

(mc.cred, pubkeyfilename, seckeyfilename,

522

438

GNUTLS_OPENPGP_FMT_BASE64);

523

439

if(ret != GNUTLS_E_SUCCESS){

524

fprintf_plus(stderr,

525

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

526

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

527

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

528

safer_gnutls_strerror(ret));

440

fprintf(stderr,

441

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

442

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

443

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

444

safer_gnutls_strerror(ret));

529

445

goto globalfail;

530

446

}

531

447

532

448

/* GnuTLS server initialization */

533

449

ret = gnutls_dh_params_init(&mc.dh_params);

534

450

if(ret != GNUTLS_E_SUCCESS){

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

536

" initialization: %s\n",

537

safer_gnutls_strerror(ret));

451

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

452

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

538

453

goto globalfail;

539

454

}

540

455

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

541

456

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

457

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

458

safer_gnutls_strerror(ret));

544

459

goto globalfail;

545

460

}

546

461

559

474

static int init_gnutls_session(gnutls_session_t *session){

560

475

int ret;

561

476

/* GnuTLS session creation */

562

do {

563

ret = gnutls_init(session, GNUTLS_SERVER);

564

if(quit_now){

565

return -1;

566

}

567

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

477

ret = gnutls_init(session, GNUTLS_SERVER);

568

478

if(ret != GNUTLS_E_SUCCESS){

569

fprintf_plus(stderr,

570

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

571

safer_gnutls_strerror(ret));

479

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

480

safer_gnutls_strerror(ret));

572

481

}

573

482

574

483

{

575

484

const char *err;

576

do {

577

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

578

if(quit_now){

579

gnutls_deinit(*session);

580

return -1;

581

}

582

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

485

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

583

486

if(ret != GNUTLS_E_SUCCESS){

584

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

585

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

586

safer_gnutls_strerror(ret));

487

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

488

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

489

safer_gnutls_strerror(ret));

587

490

gnutls_deinit(*session);

588

491

return -1;

589

492

}

590

493

}

591

494

592

do {

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

594

mc.cred);

595

if(quit_now){

596

gnutls_deinit(*session);

597

return -1;

598

}

599

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

495

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

496

mc.cred);

600

497

if(ret != GNUTLS_E_SUCCESS){

601

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

602

safer_gnutls_strerror(ret));

498

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

499

safer_gnutls_strerror(ret));

603

500

gnutls_deinit(*session);

604

501

return -1;

605

502

}

606

503

607

504

/* ignore client certificate if any. */

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

505

gnutls_certificate_server_set_request(*session,

506

GNUTLS_CERT_IGNORE);

609

507

610

508

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

611

509

616

514

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

617

515

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

618

516

517

sig_atomic_t quit_now = 0;

518

int signal_received = 0;

519

619

520

/* Called when a Mandos server is found */

620

521

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

621

522

AvahiIfIndex if_index,

627

528

struct sockaddr_in6 in6;

628

529

} to;

629

530

char *buffer = NULL;

630

char *decrypted_buffer = NULL;

531

char *decrypted_buffer;

631

532

size_t buffer_length = 0;

632

533

size_t buffer_capacity = 0;

534

ssize_t decrypted_buffer_size;

633

535

size_t written;

634

int retval = -1;

536

int retval = 0;

635

537

gnutls_session_t session;

636

538

int pf; /* Protocol family */

637

539

638

errno = 0;

639

640

540

if(quit_now){

641

errno = EINTR;

642

541

return -1;

643

542

}

644

543

650

549

pf = PF_INET;

651

550

break;

652

551

default:

653

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

654

errno = EINVAL;

552

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

655

553

return -1;

656

554

}

657

555

661

559

}

662

560

663

561

if(debug){

664

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

665

PRIu16 "\n", ip, port);

562

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

563

"\n", ip, port);

666

564

}

667

565

668

566

tcp_sd = socket(pf, SOCK_STREAM, 0);

669

567

if(tcp_sd < 0){

670

int e = errno;

671

perror_plus("socket");

672

errno = e;

568

perror("socket");

569

retval = -1;

673

570

goto mandos_end;

674

571

}

675

572

676

573

if(quit_now){

677

errno = EINTR;

678

574

goto mandos_end;

679

575

}

680

576

687

583

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

688

584

}

689

585

if(ret < 0 ){

690

int e = errno;

691

perror_plus("inet_pton");

692

errno = e;

586

perror("inet_pton");

587

retval = -1;

693

588

goto mandos_end;

694

589

}

695

590

if(ret == 0){

696

int e = errno;

697

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

698

errno = e;

591

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

592

retval = -1;

699

593

goto mandos_end;

700

594

}

701

595

if(af == AF_INET6){

705

599

706

600

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

601

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

708

-Wunreachable-code*/

602

-Wunreachable-code*/

709

603

if(if_index == AVAHI_IF_UNSPEC){

710

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

711

" incomplete without a network interface\n");

712

errno = EINVAL;

604

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

605

" without a network interface\n");

606

retval = -1;

713

607

goto mandos_end;

714

608

}

715

609

/* Set the network interface number as scope */

722

616

}

723

617

724

618

if(quit_now){

725

errno = EINTR;

726

619

goto mandos_end;

727

620

}

728

621

730

623

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

731

624

char interface[IF_NAMESIZE];

732

625

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

733

perror_plus("if_indextoname");

626

perror("if_indextoname");

734

627

} else {

735

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

736

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

628

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

629

ip, interface, port);

737

630

}

738

631

} else {

739

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

740

ip, port);

632

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

633

port);

741

634

}

742

635

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

743

636

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

750

643

sizeof(addrstr));

751

644

}

752

645

if(pcret == NULL){

753

perror_plus("inet_ntop");

646

perror("inet_ntop");

754

647

} else {

755

648

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

756

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

649

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

757

650

}

758

651

}

759

652

}

760

653

761

654

if(quit_now){

762

errno = EINTR;

763

655

goto mandos_end;

764

656

}

765

657

769

661

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

770

662

}

771

663

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

664

perror("connect");

665

retval = -1;

777

666

goto mandos_end;

778

667

}

779

668

780

669

if(quit_now){

781

errno = EINTR;

782

670

goto mandos_end;

783

671

}

784

672

787

675

while(true){

788

676

size_t out_size = strlen(out);

789

677

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

790

out_size - written));

678

out_size - written));

791

679

if(ret == -1){

792

int e = errno;

793

perror_plus("write");

794

errno = e;

680

perror("write");

681

retval = -1;

795

682

goto mandos_end;

796

683

}

797

684

written += (size_t)ret;

807

694

}

808

695

809

696

if(quit_now){

810

errno = EINTR;

811

697

goto mandos_end;

812

698

}

813

699

}

814

700

815

701

if(debug){

816

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

817

}

818

819

if(quit_now){

820

errno = EINTR;

821

goto mandos_end;

822

}

823

824

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

825

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

826

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

827

gnutls_transport_set_ptr(session,

828

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

829

830

if(quit_now){

831

errno = EINTR;

832

goto mandos_end;

833

}

834

835

do {

702

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

703

}

704

705

if(quit_now){

706

goto mandos_end;

707

}

708

709

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

710

711

if(quit_now){

712

goto mandos_end;

713

}

714

715

do{

836

716

ret = gnutls_handshake(session);

837

717

if(quit_now){

838

errno = EINTR;

839

718

goto mandos_end;

840

719

}

841

720

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

842

721

843

722

if(ret != GNUTLS_E_SUCCESS){

844

723

if(debug){

845

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

724

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

846

725

gnutls_perror(ret);

847

726

}

848

errno = EPROTO;

727

retval = -1;

849

728

goto mandos_end;

850

729

}

851

730

852

731

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

853

732

854

733

if(debug){

855

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

856

" %s\n", ip);

734

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

735

ip);

857

736

}

858

737

859

738

while(true){

860

739

861

740

if(quit_now){

862

errno = EINTR;

863

741

goto mandos_end;

864

742

}

865

743

866

744

buffer_capacity = incbuffer(&buffer, buffer_length,

867

buffer_capacity);

745

buffer_capacity);

868

746

if(buffer_capacity == 0){

869

int e = errno;

870

perror_plus("incbuffer");

871

errno = e;

747

perror("incbuffer");

748

retval = -1;

872

749

goto mandos_end;

873

750

}

874

751

875

752

if(quit_now){

876

errno = EINTR;

877

753

goto mandos_end;

878

754

}

879

755

888

764

case GNUTLS_E_AGAIN:

889

765

break;

890

766

case GNUTLS_E_REHANDSHAKE:

891

do {

767

do{

892

768

ret = gnutls_handshake(session);

893

769

894

770

if(quit_now){

895

errno = EINTR;

896

771

goto mandos_end;

897

772

}

898

773

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

899

774

if(ret < 0){

900

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

901

"***\n");

775

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

902

776

gnutls_perror(ret);

903

errno = EPROTO;

777

retval = -1;

904

778

goto mandos_end;

905

779

}

906

780

break;

907

781

default:

908

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

909

" encrypted session with Mandos server\n");

782

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

783

" encrypted session with Mandos server\n");

784

retval = -1;

910

785

gnutls_bye(session, GNUTLS_SHUT_RDWR);

911

errno = EIO;

912

786

goto mandos_end;

913

787

}

914

788

} else {

917

791

}

918

792

919

793

if(debug){

920

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

921

}

922

923

if(quit_now){

924

errno = EINTR;

925

goto mandos_end;

926

}

927

928

do {

929

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

930

if(quit_now){

931

errno = EINTR;

932

goto mandos_end;

933

}

934

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

794

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

795

}

796

797

if(quit_now){

798

goto mandos_end;

799

}

800

801

gnutls_bye(session, GNUTLS_SHUT_RDWR);

802

803

if(quit_now){

804

goto mandos_end;

805

}

935

806

936

807

if(buffer_length > 0){

937

ssize_t decrypted_buffer_size;

938

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

808

decrypted_buffer_size = pgp_packet_decrypt(buffer,

809

buffer_length,

939

810

&decrypted_buffer);

940

811

if(decrypted_buffer_size >= 0){

941

942

812

written = 0;

943

813

while(written < (size_t) decrypted_buffer_size){

944

814

if(quit_now){

945

errno = EINTR;

946

815

goto mandos_end;

947

816

}

948

817

950

819

(size_t)decrypted_buffer_size - written,

951

820

stdout);

952

821

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

953

int e = errno;

954

822

if(debug){

955

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

956

strerror(errno));

823

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

824

strerror(errno));

957

825

}

958

errno = e;

959

goto mandos_end;

826

retval = -1;

827

break;

960

828

}

961

829

written += (size_t)ret;

962

830

}

963

retval = 0;

831

free(decrypted_buffer);

832

} else {

833

retval = -1;

964

834

}

835

} else {

836

retval = -1;

965

837

}

966

838

967

839

/* Shutdown procedure */

968

840

969

841

mandos_end:

970

{

971

int e = errno;

972

free(decrypted_buffer);

973

free(buffer);

974

if(tcp_sd >= 0){

975

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

976

}

977

if(ret == -1){

978

if(e == 0){

979

e = errno;

980

}

981

perror_plus("close");

982

}

983

gnutls_deinit(session);

984

errno = e;

985

if(quit_now){

986

errno = EINTR;

987

retval = -1;

988

}

842

free(buffer);

843

if(tcp_sd >= 0){

844

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

845

}

846

if(ret == -1){

847

perror("close");

848

}

849

gnutls_deinit(session);

850

if(quit_now){

851

retval = -1;

989

852

}

990

853

return retval;

991

854

}

1016

879

switch(event){

1017

880

default:

1018

881

case AVAHI_RESOLVER_FAILURE:

1019

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

1020

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

1021

domain,

1022

avahi_strerror(avahi_server_errno(mc.server)));

882

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

883

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

884

avahi_strerror(avahi_server_errno(mc.server)));

1023

885

break;

1024

886

1025

887

case AVAHI_RESOLVER_FOUND:

1027

889

char ip[AVAHI_ADDRESS_STR_MAX];

1028

890

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

1029

891

if(debug){

1030

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

1031

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

1032

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

892

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

893

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

894

ip, (intmax_t)interface, port);

1033

895

}

1034

896

int ret = start_mandos_communication(ip, port, interface,

1035

897

avahi_proto_to_af(proto));

1036

898

if(ret == 0){

1037

899

avahi_simple_poll_quit(mc.simple_poll);

1038

} else {

1039

if(not add_server(ip, port, interface,

1040

avahi_proto_to_af(proto))){

1041

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

1042

" list\n", name);

1043

}

1044

900

}

1045

901

}

1046

902

}

1070

926

default:

1071

927

case AVAHI_BROWSER_FAILURE:

1072

928

1073

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

1074

avahi_strerror(avahi_server_errno(mc.server)));

929

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

930

avahi_strerror(avahi_server_errno(mc.server)));

1075

931

avahi_simple_poll_quit(mc.simple_poll);

1076

932

return;

1077

933

1084

940

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

1085

941

name, type, domain, protocol, 0,

1086

942

resolve_callback, NULL) == NULL)

1087

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

1088

" %s\n", name,

1089

avahi_strerror(avahi_server_errno(mc.server)));

943

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

944

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

1090

945

break;

1091

946

1092

947

case AVAHI_BROWSER_REMOVE:

1095

950

case AVAHI_BROWSER_ALL_FOR_NOW:

1096

951

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1097

952

if(debug){

1098

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

1099

" searching...\n");

953

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

1100

954

}

1101

955

break;

1102

956

}

1103

957

}

1104

958

1105

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

959

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

1106

960

static void handle_sigterm(int sig){

1107

961

if(quit_now){

1108

962

return;

1110

964

quit_now = 1;

1111

965

signal_received = sig;

1112

966

int old_errno = errno;

1113

/* set main loop to exit */

1114

967

if(mc.simple_poll != NULL){

1115

968

avahi_simple_poll_quit(mc.simple_poll);

1116

969

}

1117

970

errno = old_errno;

1118

971

}

1119

972

1120

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

1121

int ret;

1122

1123

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

1124

if(s < 0){

1125

perror_plus("socket");

1126

return false;

1127

}

1128

strcpy(ifr->ifr_name, ifname);

1129

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1130

if(ret == -1){

1131

if(debug){

1132

perror_plus("ioctl SIOCGIFFLAGS");

1133

}

1134

return false;

1135

}

1136

return true;

1137

}

1138

1139

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

1140

1141

/* Reject the loopback device */

1142

if(ifr->ifr_flags & IFF_LOOPBACK){

1143

if(debug){

1144

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

1145

ifname);

1146

}

1147

return false;

1148

}

1149

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

1150

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

1151

if(debug){

1152

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

1153

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

1154

}

1155

return true;

1156

}

1157

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

1158

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

1159

if(debug){

1160

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1161

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

1162

}

1163

return false;

1164

}

1165

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

1166

if(ifr->ifr_flags & IFF_NOARP){

1167

if(debug){

1168

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

1169

ifname);

1170

}

1171

return false;

1172

}

1173

1174

/* Accept this device */

1175

if(debug){

1176

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

1177

}

1178

return true;

1179

}

1180

1181

/*

1182

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

1183

* corresponds to an acceptable network device.

1184

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

1185

*/

1186

int good_interface(const struct dirent *if_entry){

1187

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

1188

return 0;

1189

}

1190

1191

struct ifreq ifr;

1192

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

1193

if(debug){

1194

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

1195

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

1196

}

1197

return 0;

1198

}

1199

1200

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

1201

return 0;

1202

}

1203

return 1;

1204

}

1205

1206

/*

1207

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

1208

* corresponds to an acceptable network device which is up.

1209

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

1210

*/

1211

int up_interface(const struct dirent *if_entry){

1212

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

1213

return 0;

1214

}

1215

1216

struct ifreq ifr;

1217

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

1218

if(debug){

1219

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

1220

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

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject down interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

/* Reject non-running interfaces */

1235

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

1236

if(debug){

1237

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

1238

if_entry->d_name);

1239

}

1240

return 0;

1241

}

1242

1243

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

1244

return 0;

1245

}

1246

return 1;

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

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

1394

const float delay){

1395

struct dirent **direntries;

1396

struct dirent *direntry;

1397

int ret;

1398

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

1399

alphasort);

1400

if(numhooks == -1){

1401

perror_plus("scandir");

1402

} else {

1403

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

1404

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

1405

direntry = direntries[i];

1406

char *fullname = NULL;

1407

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

1408

if(ret < 0){

1409

perror_plus("asprintf");

1410

continue;

1411

}

1412

if(debug){

1413

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

1414

direntry->d_name);

1415

}

1416

pid_t hook_pid = fork();

1417

if(hook_pid == 0){

1418

/* Child */

1419

/* Raise privileges */

1420

errno = 0;

1421

ret = seteuid(0);

1422

if(ret == -1){

1423

perror_plus("seteuid");

1424

}

1425

/* Raise privileges even more */

1426

errno = 0;

1427

ret = setuid(0);

1428

if(ret == -1){

1429

perror_plus("setuid");

1430

}

1431

/* Set group */

1432

errno = 0;

1433

ret = setgid(0);

1434

if(ret == -1){

1435

perror_plus("setgid");

1436

}

1437

/* Reset supplementary groups */

1438

errno = 0;

1439

ret = setgroups(0, NULL);

1440

if(ret == -1){

1441

perror_plus("setgroups");

1442

}

1443

dup2(devnull, STDIN_FILENO);

1444

close(devnull);

1445

dup2(STDERR_FILENO, STDOUT_FILENO);

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

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

1462

if(ret == -1){

1463

perror_plus("setenv");

1464

_exit(EX_OSERR);

1465

}

1466

char *delaystring;

1467

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

1468

if(ret == -1){

1469

perror_plus("asprintf");

1470

_exit(EX_OSERR);

1471

}

1472

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

1473

if(ret == -1){

1474

free(delaystring);

1475

perror_plus("setenv");

1476

_exit(EX_OSERR);

1477

}

1478

free(delaystring);

1479

if(connect_to != NULL){

1480

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

1481

if(ret == -1){

1482

perror_plus("setenv");

1483

_exit(EX_OSERR);

1484

}

1485

}

1486

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

1487

perror_plus("execl");

1488

_exit(EXIT_FAILURE);

1489

}

1490

} else {

1491

int status;

1492

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

1493

perror_plus("waitpid");

1494

free(fullname);

1495

continue;

1496

}

1497

if(WIFEXITED(status)){

1498

if(WEXITSTATUS(status) != 0){

1499

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

1500

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

1501

WEXITSTATUS(status));

1502

free(fullname);

1503

continue;

1504

}

1505

} else if(WIFSIGNALED(status)){

1506

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

1507

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

1508

WTERMSIG(status));

1509

free(fullname);

1510

continue;

1511

} else {

1512

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

1513

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

1514

free(fullname);

1515

continue;

1516

}

1517

}

1518

free(fullname);

1519

if(debug){

1520

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

1521

direntry->d_name);

1522

}

1523

}

1524

close(devnull);

1525

}

1526

return true;

1527

}

1528

1529

973

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

1530

974

AvahiSServiceBrowser *sb = NULL;

1531

975

int error;

1533

977

intmax_t tmpmax;

1534

978

char *tmp;

1535

979

int exitcode = EXIT_SUCCESS;

1536

const char *interface = "";

980

const char *interface = "eth0";

1537

981

struct ifreq network;

1538

982

int sd = -1;

1539

983

bool take_down_interface = false;

1540

984

uid_t uid;

1541

985

gid_t gid;

986

char *connect_to = NULL;

1542

987

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

1543

988

bool tempdir_created = false;

1544

989

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1548

993

bool gnutls_initialized = false;

1549

994

bool gpgme_initialized = false;

1550

995

float delay = 2.5f;

1551

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

1552

retrying the same server again */

1553

996

1554

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

997

struct sigaction old_sigterm_action;

1555

998

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1556

999

1557

uid = getuid();

1558

gid = getgid();

1559

1560

/* Lower any group privileges we might have, just to be safe */

1561

errno = 0;

1562

ret = setgid(gid);

1563

if(ret == -1){

1564

perror_plus("setgid");

1565

}

1566

1567

/* Lower user privileges (temporarily) */

1568

errno = 0;

1569

ret = seteuid(uid);

1570

if(ret == -1){

1571

perror_plus("seteuid");

1572

}

1573

1574

if(quit_now){

1575

goto end;

1576

}

1577

1578

1000

{

1579

1001

struct argp_option options[] = {

1580

1002

{ .name = "debug", .key = 128,

1609

1031

.arg = "SECONDS",

1610

1032

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

1611

1033

.group = 2 },

1612

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

1613

.arg = "SECONDS",

1614

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

1615

.group = 2 },

1616

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

1617

.arg = "DIR",

1618

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

1619

.group = 2 },

1620

/*

1621

* These reproduce what we would get without ARGP_NO_HELP

1622

*/

1623

{ .name = "help", .key = '?',

1624

.doc = "Give this help list", .group = -1 },

1625

{ .name = "usage", .key = -3,

1626

.doc = "Give a short usage message", .group = -1 },

1627

{ .name = "version", .key = 'V',

1628

.doc = "Print program version", .group = -1 },

1629

1034

{ .name = NULL }

1630

1035

};

1631

1036

1632

1037

error_t parse_opt(int key, char *arg,

1633

1038

struct argp_state *state){

1634

errno = 0;

1635

1039

switch(key){

1636

1040

case 128: /* --debug */

1637

1041

debug = true;

1653

1057

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

1654

1058

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

1655

1059

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1656

argp_error(state, "Bad number of DH bits");

1060

fprintf(stderr, "Bad number of DH bits\n");

1061

exit(EXIT_FAILURE);

1657

1062

}

1658

1063

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

1659

1064

break;

1664

1069

errno = 0;

1665

1070

delay = strtof(arg, &tmp);

1666

1071

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

1667

argp_error(state, "Bad delay");

1668

}

1669

case 132: /* --retry */

1670

errno = 0;

1671

retry_interval = strtod(arg, &tmp);

1672

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

1673

or (retry_interval * 1000) > INT_MAX

1674

or retry_interval < 0){

1675

argp_error(state, "Bad retry interval");

1676

}

1677

break;

1678

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

1679

hookdir = arg;

1680

break;

1681

/*

1682

* These reproduce what we would get without ARGP_NO_HELP

1683

*/

1684

case '?': /* --help */

1685

argp_state_help(state, state->out_stream,

1686

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1687

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1688

case -3: /* --usage */

1689

argp_state_help(state, state->out_stream,

1690

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1691

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

1692

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

1693

exit(argp_err_exit_status);

1072

fprintf(stderr, "Bad delay\n");

1073

exit(EXIT_FAILURE);

1074

}

1075

break;

1076

case ARGP_KEY_ARG:

1077

argp_usage(state);

1078

case ARGP_KEY_END:

1694

1079

break;

1695

1080

default:

1696

1081

return ARGP_ERR_UNKNOWN;

1697

1082

}

1698

return errno;

1083

return 0;

1699

1084

}

1700

1085

1701

1086

struct argp argp = { .options = options, .parser = parse_opt,

1702

1087

.args_doc = "",

1703

1088

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

1704

1089

" passwords from a Mandos server" };

1705

ret = argp_parse(&argp, argc, argv,

1706

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1707

switch(ret){

1708

case 0:

1709

break;

1710

case ENOMEM:

1711

default:

1712

errno = ret;

1713

perror_plus("argp_parse");

1714

exitcode = EX_OSERR;

1715

goto end;

1716

case EINVAL:

1717

exitcode = EX_USAGE;

1718

goto end;

1719

}

1720

}

1721

1722

{

1723

/* Work around Debian bug #633582:

1724

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

1725

1726

/* Re-raise priviliges */

1727

errno = 0;

1728

ret = seteuid(0);

1729

if(ret == -1){

1730

perror_plus("seteuid");

1731

} else {

1732

struct stat st;

1733

1734

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

1735

int seckey_fd = open(seckey, O_RDONLY);

1736

if(seckey_fd == -1){

1737

perror_plus("open");

1738

} else {

1739

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

1740

if(ret == -1){

1741

perror_plus("fstat");

1742

} else {

1743

if(S_ISREG(st.st_mode)

1744

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

1745

ret = fchown(seckey_fd, uid, gid);

1746

if(ret == -1){

1747

perror_plus("fchown");

1748

}

1749

}

1750

}

1751

TEMP_FAILURE_RETRY(close(seckey_fd));

1752

}

1753

}

1754

1755

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

1756

int pubkey_fd = open(pubkey, O_RDONLY);

1757

if(pubkey_fd == -1){

1758

perror_plus("open");

1759

} else {

1760

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

1761

if(ret == -1){

1762

perror_plus("fstat");

1763

} else {

1764

if(S_ISREG(st.st_mode)

1765

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

1766

ret = fchown(pubkey_fd, uid, gid);

1767

if(ret == -1){

1768

perror_plus("fchown");

1769

}

1770

}

1771

}

1772

TEMP_FAILURE_RETRY(close(pubkey_fd));

1773

}

1774

}

1775

1776

/* Lower privileges */

1777

errno = 0;

1778

ret = seteuid(uid);

1779

if(ret == -1){

1780

perror_plus("seteuid");

1781

}

1782

}

1783

}

1784

1785

/* Run network hooks */

1786

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

1787

goto end;

1090

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

1091

if(ret == ARGP_ERR_UNKNOWN){

1092

fprintf(stderr, "Unknown error while parsing arguments\n");

1093

exitcode = EXIT_FAILURE;

1094

goto end;

1095

}

1788

1096

}

1789

1097

1790

1098

if(not debug){

1791

1099

avahi_set_log_function(empty_log);

1792

1100

}

1793

1101

1794

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

1795

struct dirent **direntries;

1796

/* First look for interfaces that are up */

1797

ret = scandir(sys_class_net, &direntries, up_interface,

1798

alphasort);

1799

if(ret == 0){

1800

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

1801

free(direntries);

1802

ret = scandir(sys_class_net, &direntries, good_interface,

1803

alphasort);

1804

}

1805

if(ret >= 1){

1806

/* Pick the first interface returned */

1807

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

1808

if(debug){

1809

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

1810

}

1811

if(interface == NULL){

1812

perror_plus("malloc");

1813

free(direntries);

1814

exitcode = EXIT_FAILURE;

1815

goto end;

1816

}

1817

free(direntries);

1818

} else {

1819

free(direntries);

1820

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

1821

exitcode = EXIT_FAILURE;

1822

goto end;

1823

}

1824

}

1825

1826

1102

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

1827

1103

from the signal handler */

1828

1104

/* Initialize the pseudo-RNG for Avahi */

1829

1105

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

1830

1106

mc.simple_poll = avahi_simple_poll_new();

1831

1107

if(mc.simple_poll == NULL){

1832

fprintf_plus(stderr,

1833

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

1834

exitcode = EX_UNAVAILABLE;

1108

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

1109

exitcode = EXIT_FAILURE;

1835

1110

goto end;

1836

1111

}

1837

1112

1838

1113

sigemptyset(&sigterm_action.sa_mask);

1839

1114

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

1840

1115

if(ret == -1){

1841

perror_plus("sigaddset");

1842

exitcode = EX_OSERR;

1116

perror("sigaddset");

1117

exitcode = EXIT_FAILURE;

1843

1118

goto end;

1844

1119

}

1845

1120

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

1846

1121

if(ret == -1){

1847

perror_plus("sigaddset");

1848

exitcode = EX_OSERR;

1122

perror("sigaddset");

1123

exitcode = EXIT_FAILURE;

1849

1124

goto end;

1850

1125

}

1851

1126

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

1852

1127

if(ret == -1){

1853

perror_plus("sigaddset");

1854

exitcode = EX_OSERR;

1128

perror("sigaddset");

1129

exitcode = EXIT_FAILURE;

1855

1130

goto end;

1856

1131

}

1857

1132

/* Need to check if the handler is SIG_IGN before handling:

1860

1135

*/

1861

1136

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

1862

1137

if(ret == -1){

1863

perror_plus("sigaction");

1864

return EX_OSERR;

1138

perror("sigaction");

1139

return EXIT_FAILURE;

1865

1140

}

1866

1141

if(old_sigterm_action.sa_handler != SIG_IGN){

1867

1142

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

1868

1143

if(ret == -1){

1869

perror_plus("sigaction");

1870

exitcode = EX_OSERR;

1144

perror("sigaction");

1145

exitcode = EXIT_FAILURE;

1871

1146

goto end;

1872

1147

}

1873

1148

}

1874

1149

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

1875

1150

if(ret == -1){

1876

perror_plus("sigaction");

1877

return EX_OSERR;

1151

perror("sigaction");

1152

return EXIT_FAILURE;

1878

1153

}

1879

1154

if(old_sigterm_action.sa_handler != SIG_IGN){

1880

1155

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

1881

1156

if(ret == -1){

1882

perror_plus("sigaction");

1883

exitcode = EX_OSERR;

1157

perror("sigaction");

1158

exitcode = EXIT_FAILURE;

1884

1159

goto end;

1885

1160

}

1886

1161

}

1887

1162

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

1888

1163

if(ret == -1){

1889

perror_plus("sigaction");

1890

return EX_OSERR;

1164

perror("sigaction");

1165

return EXIT_FAILURE;

1891

1166

}

1892

1167

if(old_sigterm_action.sa_handler != SIG_IGN){

1893

1168

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

1894

1169

if(ret == -1){

1895

perror_plus("sigaction");

1896

exitcode = EX_OSERR;

1170

perror("sigaction");

1171

exitcode = EXIT_FAILURE;

1897

1172

goto end;

1898

1173

}

1899

1174

}

1900

1175

1901

1176

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

1902

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

1177

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

1903

1178

if_index = (AvahiIfIndex) if_nametoindex(interface);

1904

1179

if(if_index == 0){

1905

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

1906

exitcode = EX_UNAVAILABLE;

1180

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

1181

exitcode = EXIT_FAILURE;

1907

1182

goto end;

1908

1183

}

1909

1184

1911

1186

goto end;

1912

1187

}

1913

1188

1914

/* Re-raise priviliges */

1915

errno = 0;

1916

ret = seteuid(0);

1917

if(ret == -1){

1918

perror_plus("seteuid");

1919

}

1920

1921

1189

#ifdef __linux__

1922

1190

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1923

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

1191

messages to mess up the prompt */

1924

1192

ret = klogctl(8, NULL, 5);

1925

1193

bool restore_loglevel = true;

1926

1194

if(ret == -1){

1927

1195

restore_loglevel = false;

1928

perror_plus("klogctl");

1196

perror("klogctl");

1929

1197

}

1930

1198

#endif /* __linux__ */

1931

1199

1932

1200

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1933

1201

if(sd < 0){

1934

perror_plus("socket");

1935

exitcode = EX_OSERR;

1202

perror("socket");

1203

exitcode = EXIT_FAILURE;

1936

1204

#ifdef __linux__

1937

1205

if(restore_loglevel){

1938

1206

ret = klogctl(7, NULL, 0);

1939

1207

if(ret == -1){

1940

perror_plus("klogctl");

1208

perror("klogctl");

1941

1209

}

1942

1210

}

1943

1211

#endif /* __linux__ */

1944

/* Lower privileges */

1945

errno = 0;

1946

ret = seteuid(uid);

1947

if(ret == -1){

1948

perror_plus("seteuid");

1949

}

1950

1212

goto end;

1951

1213

}

1952

1214

strcpy(network.ifr_name, interface);

1953

1215

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

1954

1216

if(ret == -1){

1955

perror_plus("ioctl SIOCGIFFLAGS");

1217

perror("ioctl SIOCGIFFLAGS");

1956

1218

#ifdef __linux__

1957

1219

if(restore_loglevel){

1958

1220

ret = klogctl(7, NULL, 0);

1959

1221

if(ret == -1){

1960

perror_plus("klogctl");

1222

perror("klogctl");

1961

1223

}

1962

1224

}

1963

1225

#endif /* __linux__ */

1964

exitcode = EX_OSERR;

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1226

exitcode = EXIT_FAILURE;

1971

1227

goto end;

1972

1228

}

1973

1229

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

1976

1232

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

1977

1233

if(ret == -1){

1978

1234

take_down_interface = false;

1979

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1980

exitcode = EX_OSERR;

1235

perror("ioctl SIOCSIFFLAGS");

1236

exitcode = EXIT_FAILURE;

1981

1237

#ifdef __linux__

1982

1238

if(restore_loglevel){

1983

1239

ret = klogctl(7, NULL, 0);

1984

1240

if(ret == -1){

1985

perror_plus("klogctl");

1241

perror("klogctl");

1986

1242

}

1987

1243

}

1988

1244

#endif /* __linux__ */

1989

/* Lower privileges */

1990

errno = 0;

1991

ret = seteuid(uid);

1992

if(ret == -1){

1993

perror_plus("seteuid");

1994

}

1995

1245

goto end;

1996

1246

}

1997

1247

}

1998

/* Sleep checking until interface is running.

1999

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

1248

/* sleep checking until interface is running */

2000

1249

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

2001

1250

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

2002

1251

if(ret == -1){

2003

perror_plus("ioctl SIOCGIFFLAGS");

1252

perror("ioctl SIOCGIFFLAGS");

2004

1253

} else if(network.ifr_flags & IFF_RUNNING){

2005

1254

break;

2006

1255

}

2007

1256

struct timespec sleeptime = { .tv_nsec = 250000000 };

2008

1257

ret = nanosleep(&sleeptime, NULL);

2009

1258

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

2010

perror_plus("nanosleep");

1259

perror("nanosleep");

2011

1260

}

2012

1261

}

2013

1262

if(not take_down_interface){

2014

1263

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

2015

1264

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

2016

1265

if(ret == -1){

2017

perror_plus("close");

1266

perror("close");

2018

1267

}

2019

1268

}

2020

1269

#ifdef __linux__

2022

1271

/* Restores kernel loglevel to default */

2023

1272

ret = klogctl(7, NULL, 0);

2024

1273

if(ret == -1){

2025

perror_plus("klogctl");

1274

perror("klogctl");

2026

1275

}

2027

1276

}

2028

1277

#endif /* __linux__ */

2029

/* Lower privileges */

2030

errno = 0;

2031

/* Lower privileges */

2032

ret = seteuid(uid);

2033

if(ret == -1){

2034

perror_plus("seteuid");

2035

}

1278

}

1279

1280

if(quit_now){

1281

goto end;

1282

}

1283

1284

uid = getuid();

1285

gid = getgid();

1286

1287

errno = 0;

1288

setgid(gid);

1289

if(ret == -1){

1290

perror("setgid");

1291

}

1292

1293

ret = setuid(uid);

1294

if(ret == -1){

1295

perror("setuid");

2036

1296

}

2037

1297

2038

1298

if(quit_now){

2041

1301

2042

1302

ret = init_gnutls_global(pubkey, seckey);

2043

1303

if(ret == -1){

2044

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

2045

exitcode = EX_UNAVAILABLE;

1304

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

1305

exitcode = EXIT_FAILURE;

2046

1306

goto end;

2047

1307

} else {

2048

1308

gnutls_initialized = true;

2052

1312

goto end;

2053

1313

}

2054

1314

1315

tempdir_created = true;

2055

1316

if(mkdtemp(tempdir) == NULL){

2056

perror_plus("mkdtemp");

1317

tempdir_created = false;

1318

perror("mkdtemp");

2057

1319

goto end;

2058

1320

}

2059

tempdir_created = true;

2060

1321

2061

1322

if(quit_now){

2062

1323

goto end;

2063

1324

}

2064

1325

2065

1326

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

2066

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

2067

exitcode = EX_UNAVAILABLE;

1327

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

1328

exitcode = EXIT_FAILURE;

2068

1329

goto end;

2069

1330

} else {

2070

1331

gpgme_initialized = true;

2079

1340

/* (Mainly meant for debugging) */

2080

1341

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

2081

1342

if(address == NULL){

2082

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

2083

exitcode = EX_USAGE;

1343

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

1344

exitcode = EXIT_FAILURE;

2084

1345

goto end;

2085

1346

}

2086

1347

2093

1354

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

2094

1355

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

2095

1356

or tmpmax != (uint16_t)tmpmax){

2096

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

2097

exitcode = EX_USAGE;

1357

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

1358

exitcode = EXIT_FAILURE;

2098

1359

goto end;

2099

1360

}

2100

1361

2104

1365

2105

1366

port = (uint16_t)tmpmax;

2106

1367

*address = '\0';

1368

address = connect_to;

2107

1369

/* Colon in address indicates IPv6 */

2108

1370

int af;

2109

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

1371

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

2110

1372

af = AF_INET6;

2111

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

2112

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

2113

{

2114

connect_to++;

2115

address[-1] = '\0';

2116

}

2117

1373

} else {

2118

1374

af = AF_INET;

2119

1375

}

2120

address = connect_to;

2121

1376

2122

1377

if(quit_now){

2123

1378

goto end;

2124

1379

}

2125

1380

2126

while(not quit_now){

2127

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

2128

if(quit_now or ret == 0){

2129

break;

2130

}

2131

if(debug){

2132

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

2133

(int)retry_interval);

2134

}

2135

sleep((int)retry_interval);

2136

}

2137

2138

if (not quit_now){

1381

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

1382

if(ret < 0){

1383

exitcode = EXIT_FAILURE;

1384

} else {

2139

1385

exitcode = EXIT_SUCCESS;

2140

1386

}

2141

2142

1387

goto end;

2143

1388

}

2144

1389

2166

1411

2167

1412

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

2168

1413

if(mc.server == NULL){

2169

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

2170

avahi_strerror(error));

2171

exitcode = EX_UNAVAILABLE;

1414

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

1415

avahi_strerror(error));

1416

exitcode = EXIT_FAILURE;

2172

1417

goto end;

2173

1418

}

2174

1419

2181

1426

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2182

1427

NULL, 0, browse_callback, NULL);

2183

1428

if(sb == NULL){

2184

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

2185

avahi_strerror(avahi_server_errno(mc.server)));

2186

exitcode = EX_UNAVAILABLE;

1429

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

1430

avahi_strerror(avahi_server_errno(mc.server)));

1431

exitcode = EXIT_FAILURE;

2187

1432

goto end;

2188

1433

}

2189

1434

2194

1439

/* Run the main loop */

2195

1440

2196

1441

if(debug){

2197

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

2198

}

2199

2200

ret = avahi_loop_with_timeout(mc.simple_poll,

2201

(int)(retry_interval * 1000));

2202

if(debug){

2203

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

2204

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

2205

}

1442

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

1443

}

1444

1445

avahi_simple_poll_loop(mc.simple_poll);

2206

1446

2207

1447

end:

2208

1448

2209

1449

if(debug){

2210

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

1450

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

2211

1451

}

2212

1452

2213

1453

/* Cleanup things */

2230

1470

gpgme_release(mc.ctx);

2231

1471

}

2232

1472

2233

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

2234

has seen */

2235

if(mc.current_server != NULL){

2236

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

2237

while(mc.current_server != NULL){

2238

server *next = mc.current_server->next;

2239

free(mc.current_server);

2240

mc.current_server = next;

2241

}

2242

}

2243

2244

/* Run network hooks */

2245

run_network_hooks("stop", interface, delay);

2246

2247

/* Re-raise priviliges */

2248

{

2249

errno = 0;

2250

ret = seteuid(0);

2251

if(ret == -1){

2252

perror_plus("seteuid");

2253

}

2254

2255

/* Take down the network interface */

2256

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

2257

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

2258

if(ret == -1){

2259

perror_plus("ioctl SIOCGIFFLAGS");

2260

} else if(network.ifr_flags & IFF_UP){

2261

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

2262

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

2263

if(ret == -1){

2264

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2265

}

2266

}

2267

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

2268

if(ret == -1){

2269

perror_plus("close");

2270

}

2271

}

2272

}

2273

/* Lower privileges permanently */

2274

errno = 0;

2275

ret = setuid(uid);

2276

if(ret == -1){

2277

perror_plus("setuid");

2278

}

2279

2280

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

1473

/* Take down the network interface */

1474

if(take_down_interface){

1475

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

1476

if(ret == -1){

1477

perror("ioctl SIOCGIFFLAGS");

1478

} else if(network.ifr_flags & IFF_UP) {

1479

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

1480

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

1481

if(ret == -1){

1482

perror("ioctl SIOCSIFFLAGS");

1483

}

1484

}

1485

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

1486

if(ret == -1){

1487

perror("close");

1488

}

1489

}

1490

1491

/* Removes the temp directory used by GPGME */

2281

1492

if(tempdir_created){

2282

struct dirent **direntries = NULL;

2283

struct dirent *direntry = NULL;

2284

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

2285

alphasort);

2286

if (numentries > 0){

2287

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

2288

direntry = direntries[i];

1493

DIR *d;

1494

struct dirent *direntry;

1495

d = opendir(tempdir);

1496

if(d == NULL){

1497

if(errno != ENOENT){

1498

perror("opendir");

1499

}

1500

} else {

1501

while(true){

1502

direntry = readdir(d);

1503

if(direntry == NULL){

1504

break;

1505

}

1506

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

1507

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

1508

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

1509

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

1510

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

1511

continue;

1512

}

2289

1513

char *fullname = NULL;

2290

1514

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

2291

1515

direntry->d_name);

2292

1516

if(ret < 0){

2293

perror_plus("asprintf");

1517

perror("asprintf");

2294

1518

continue;

2295

1519

}

2296

1520

ret = remove(fullname);

2297

1521

if(ret == -1){

2298

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

2299

strerror(errno));

1522

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

1523

strerror(errno));

2300

1524

}

2301

1525

free(fullname);

2302

1526

}

2303

}

2304

2305

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

2306

free(direntries);

2307

if (numentries == -1){

2308

perror_plus("scandir");

1527

closedir(d);

2309

1528

}

2310

1529

ret = rmdir(tempdir);

2311

1530

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

2312

perror_plus("rmdir");

1531

perror("rmdir");

2313

1532

}

2314

1533

}

2315

1534

2316

1535

if(quit_now){

2317

1536

sigemptyset(&old_sigterm_action.sa_mask);

2318

1537

old_sigterm_action.sa_handler = SIG_DFL;

2319

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2320

&old_sigterm_action,

2321

NULL));

1538

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

2322

1539

if(ret == -1){

2323

perror_plus("sigaction");

2324

}

2325

do {

2326

ret = raise(signal_received);

2327

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

2328

if(ret != 0){

2329

perror_plus("raise");

2330

abort();

2331

}

2332

TEMP_FAILURE_RETRY(pause());

1540

perror("sigaction");

1541

}

1542

raise(signal_received);

2333

1543

}

2334

1544

2335

1545

return exitcode;