/mandos/release : revision 237.7.302

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

26

* along with this program. If not, see

27

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

28

*

29

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

29

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

30

*/

31

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

41

42

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

43

stdout, ferror(), remove() */

44

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

43

stdout, ferror() */

44

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

45

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

46

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

47

strtof(), abort() */

53

sockaddr_in6, PF_INET6,

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

56

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

56

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

57

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

58

inet_pton(), connect() */

59

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

61

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

61

62

*/

62

63

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

63

64

strtoimax() */

64

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

65

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

66

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

65

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

66

program_invocation_short_name */

67

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

67

68

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

68

69

SIOCSIFFLAGS, if_indextoname(),

69

70

if_nametoindex(), IF_NAMESIZE */

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

unlinkat() */

78

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

77

79

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

78

80

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

79

81

argp_state, struct argp,

84

86

raise() */

85

87

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

86

88

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

89

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

90

WEXITSTATUS(), WTERMSIG() */

91

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

92

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

93

argz_delete(), argz_append(),

94

argz_stringify(), argz_add(),

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

87

98

88

99

#ifdef __linux__

89

100

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

107

118

init_gnutls_session(),

108

119

GNUTLS_* */

109

120

#include <gnutls/openpgp.h>

110

/* gnutls_certificate_set_openpgp_key_file(),

111

GNUTLS_OPENPGP_FMT_BASE64 */

121

/* gnutls_certificate_set_openpgp_key_file(),

122

GNUTLS_OPENPGP_FMT_BASE64 */

112

123

113

124

/* GPGME */

114

125

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

122

133

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

123

134

#define SECKEY "seckey.txt"

124

135

#define PUBKEY "pubkey.txt"

136

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

125

137

126

138

bool debug = false;

127

139

static const char mandos_protocol_version[] = "1";

128

140

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

129

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

141

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

142

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

143

char *connect_to = NULL;

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

148

149

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

150

typedef struct server{

151

const char *ip;

152

in_port_t port;

153

AvahiIfIndex if_index;

154

int af;

155

struct timespec last_seen;

156

struct server *next;

157

struct server *prev;

158

} server;

130

159

131

160

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

132

161

typedef struct {

133

AvahiSimplePoll *simple_poll;

134

162

AvahiServer *server;

135

163

gnutls_certificate_credentials_t cred;

136

164

unsigned int dh_bits;

137

165

gnutls_dh_params_t dh_params;

138

166

const char *priority;

139

167

gpgme_ctx_t ctx;

168

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

140

171

} mandos_context;

141

172

142

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

143

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

144

.dh_bits = 1024, .priority = "SECURE256"

145

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

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

146

175

147

176

sig_atomic_t quit_now = 0;

148

177

int signal_received = 0;

149

178

179

/* Function to use when printing errors */

180

void perror_plus(const char *print_text){

181

int e = errno;

182

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

183

program_invocation_short_name);

184

errno = e;

185

perror(print_text);

186

}

187

188

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

189

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

190

va_list ap;

191

va_start (ap, format);

192

193

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

194

program_invocation_short_name));

195

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

196

}

197

150

198

/*

151

199

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

152

200

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

153

201

* "buffer_length" is how much is already used.

154

202

*/

203

__attribute__((nonnull, warn_unused_result))

155

204

size_t incbuffer(char **buffer, size_t buffer_length,

156

size_t buffer_capacity){

205

size_t buffer_capacity){

157

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

158

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

159

if(buffer == NULL){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

160

213

return 0;

161

214

}

215

*buffer = new_buf;

162

216

buffer_capacity += BUFFER_SIZE;

163

217

}

164

218

return buffer_capacity;

165

219

}

166

220

221

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

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

225

int ret;

226

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

227

if(new_server == NULL){

228

perror_plus("malloc");

229

return false;

230

}

231

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

232

.port = port,

233

.if_index = if_index,

234

.af = af };

235

if(new_server->ip == NULL){

236

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

253

}

254

/* Special case of first server */

255

if(*current_server == NULL){

256

new_server->next = new_server;

257

new_server->prev = new_server;

258

*current_server = new_server;

259

} else {

260

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

261

new_server->next = *current_server;

262

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

263

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

267

}

268

167

269

/*

168

270

* Initialize GPGME.

169

271

*/

170

static bool init_gpgme(const char *seckey,

171

const char *pubkey, const char *tempdir){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

172

277

gpgme_error_t rc;

173

278

gpgme_engine_info_t engine_info;

174

279

175

176

280

/*

177

281

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

178

282

*/

179

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

180

284

int ret;

181

285

int fd;

182

286

gpgme_data_t pgp_data;

183

287

184

288

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

185

289

if(fd == -1){

186

perror("open");

290

perror_plus("open");

187

291

return false;

188

292

}

189

293

190

294

rc = gpgme_data_new_from_fd(&pgp_data, fd);

191

295

if(rc != GPG_ERR_NO_ERROR){

192

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

193

gpgme_strsource(rc), gpgme_strerror(rc));

296

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

297

gpgme_strsource(rc), gpgme_strerror(rc));

194

298

return false;

195

299

}

196

300

197

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

198

302

if(rc != GPG_ERR_NO_ERROR){

199

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

200

gpgme_strsource(rc), gpgme_strerror(rc));

303

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

304

gpgme_strsource(rc), gpgme_strerror(rc));

201

305

return false;

202

306

}

203

307

204

308

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

205

309

if(ret == -1){

206

perror("close");

310

perror_plus("close");

207

311

}

208

312

gpgme_data_release(pgp_data);

209

313

return true;

210

314

}

211

315

212

316

if(debug){

213

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

317

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

214

318

}

215

319

216

320

/* Init GPGME */

217

321

gpgme_check_version(NULL);

218

322

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

219

323

if(rc != GPG_ERR_NO_ERROR){

220

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

221

gpgme_strsource(rc), gpgme_strerror(rc));

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

222

326

return false;

223

327

}

224

328

225

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

329

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

226

330

rc = gpgme_get_engine_info(&engine_info);

227

331

if(rc != GPG_ERR_NO_ERROR){

228

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

229

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

230

334

return false;

231

335

}

232

336

while(engine_info != NULL){

238

342

engine_info = engine_info->next;

239

343

}

240

344

if(engine_info == NULL){

241

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

345

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

346

tempdir);

242

347

return false;

243

348

}

244

349

245

350

/* Create new GPGME "context" */

246

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

351

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

247

352

if(rc != GPG_ERR_NO_ERROR){

248

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

249

gpgme_strsource(rc), gpgme_strerror(rc));

353

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

354

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

355

gpgme_strerror(rc));

250

356

return false;

251

357

}

252

358

261

367

* Decrypt OpenPGP data.

262

368

* Returns -1 on error

263

369

*/

370

__attribute__((nonnull, warn_unused_result))

264

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

265

372

size_t crypto_size,

266

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

267

375

gpgme_data_t dh_crypto, dh_plain;

268

376

gpgme_error_t rc;

269

377

ssize_t ret;

271

379

ssize_t plaintext_length = 0;

272

380

273

381

if(debug){

274

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

382

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

275

383

}

276

384

277

385

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

278

386

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

279

387

0);

280

388

if(rc != GPG_ERR_NO_ERROR){

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

283

391

return -1;

284

392

}

285

393

286

394

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

287

395

rc = gpgme_data_new(&dh_plain);

288

396

if(rc != GPG_ERR_NO_ERROR){

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

291

400

gpgme_data_release(dh_crypto);

292

401

return -1;

293

402

}

294

403

295

404

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

296

405

data buffer */

297

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

406

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

298

407

if(rc != GPG_ERR_NO_ERROR){

299

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

300

gpgme_strsource(rc), gpgme_strerror(rc));

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

301

410

plaintext_length = -1;

302

411

if(debug){

303

412

gpgme_decrypt_result_t result;

304

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

305

414

if(result == NULL){

306

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

415

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

307

416

} else {

308

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

309

result->unsupported_algorithm);

310

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

311

result->wrong_key_usage);

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

312

421

if(result->file_name != NULL){

313

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

422

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

314

423

}

315

424

gpgme_recipient_t recipient;

316

425

recipient = result->recipients;

317

426

while(recipient != NULL){

318

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

319

gpgme_pubkey_algo_name(recipient->pubkey_algo));

320

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

321

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

322

recipient->status == GPG_ERR_NO_SECKEY

323

? "No" : "Yes");

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

324

434

recipient = recipient->next;

325

435

}

326

436

}

329

439

}

330

440

331

441

if(debug){

332

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

442

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

333

443

}

334

444

335

445

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

336

446

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

337

perror("gpgme_data_seek");

447

perror_plus("gpgme_data_seek");

338

448

plaintext_length = -1;

339

449

goto decrypt_end;

340

450

}

342

452

*plaintext = NULL;

343

453

while(true){

344

454

plaintext_capacity = incbuffer(plaintext,

345

(size_t)plaintext_length,

346

plaintext_capacity);

455

(size_t)plaintext_length,

456

plaintext_capacity);

347

457

if(plaintext_capacity == 0){

348

perror("incbuffer");

349

plaintext_length = -1;

350

goto decrypt_end;

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

351

461

}

352

462

353

463

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

358

468

break;

359

469

}

360

470

if(ret < 0){

361

perror("gpgme_data_read");

471

perror_plus("gpgme_data_read");

362

472

plaintext_length = -1;

363

473

goto decrypt_end;

364

474

}

366

476

}

367

477

368

478

if(debug){

369

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

479

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

370

480

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

371

481

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

372

482

}

383

493

return plaintext_length;

384

494

}

385

495

386

static const char * safer_gnutls_strerror(int value){

387

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

388

-Wunreachable-code */

389

if(ret == NULL)

390

ret = "(unknown)";

391

return ret;

496

__attribute__((warn_unused_result, const))

497

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

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

__attribute__((warn_unused_result))

504

static const char *safer_gnutls_strerror(int value){

505

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

392

507

}

393

508

394

509

/* GnuTLS log function callback */

510

__attribute__((nonnull))

395

511

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

396

512

const char* string){

397

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

513

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

398

514

}

399

515

516

__attribute__((nonnull, warn_unused_result))

400

517

static int init_gnutls_global(const char *pubkeyfilename,

401

const char *seckeyfilename){

518

const char *seckeyfilename,

519

mandos_context *mc){

402

520

int ret;

521

unsigned int uret;

403

522

404

523

if(debug){

405

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

524

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

406

525

}

407

526

408

527

ret = gnutls_global_init();

409

528

if(ret != GNUTLS_E_SUCCESS){

410

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

411

safer_gnutls_strerror(ret));

529

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

530

safer_gnutls_strerror(ret));

412

531

return -1;

413

532

}

414

533

421

540

}

422

541

423

542

/* OpenPGP credentials */

424

gnutls_certificate_allocate_credentials(&mc.cred);

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

425

544

if(ret != GNUTLS_E_SUCCESS){

426

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

427

from

428

-Wunreachable-code

429

*/

430

safer_gnutls_strerror(ret));

545

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

546

safer_gnutls_strerror(ret));

431

547

gnutls_global_deinit();

432

548

return -1;

433

549

}

434

550

435

551

if(debug){

436

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

437

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

438

seckeyfilename);

552

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

553

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

554

pubkeyfilename,

555

seckeyfilename);

439

556

}

440

557

441

558

ret = gnutls_certificate_set_openpgp_key_file

442

(mc.cred, pubkeyfilename, seckeyfilename,

559

(mc->cred, pubkeyfilename, seckeyfilename,

443

560

GNUTLS_OPENPGP_FMT_BASE64);

444

561

if(ret != GNUTLS_E_SUCCESS){

445

fprintf(stderr,

446

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

447

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

448

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

449

safer_gnutls_strerror(ret));

562

fprintf_plus(stderr,

563

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

564

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

565

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

566

safer_gnutls_strerror(ret));

450

567

goto globalfail;

451

568

}

452

569

453

570

/* GnuTLS server initialization */

454

ret = gnutls_dh_params_init(&mc.dh_params);

571

ret = gnutls_dh_params_init(&mc->dh_params);

455

572

if(ret != GNUTLS_E_SUCCESS){

456

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

457

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

573

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

574

" initialization: %s\n",

575

safer_gnutls_strerror(ret));

458

576

goto globalfail;

459

577

}

460

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

578

if(mc->dh_bits == 0){

579

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

580

/* Try to read the private key file */

581

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

582

{

583

int secfile = open(seckeyfilename, O_RDONLY);

584

size_t buffer_capacity = 0;

585

while(true){

586

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

587

(size_t)buffer.size,

588

(size_t)buffer_capacity);

589

if(buffer_capacity == 0){

590

perror_plus("incbuffer");

591

free(buffer.data);

592

buffer.data = NULL;

593

break;

594

}

595

ssize_t bytes_read = read(secfile, buffer.data + buffer.size,

596

BUFFER_SIZE);

597

/* EOF */

598

if(bytes_read == 0){

599

break;

600

}

601

/* check bytes_read for failure */

602

if(bytes_read < 0){

603

perror_plus("read");

604

free(buffer.data);

605

buffer.data = NULL;

606

break;

607

}

608

buffer.size += (unsigned int)bytes_read;

609

}

610

close(secfile);

611

}

612

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

613

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

614

if(buffer.data != NULL){

615

{

616

gnutls_openpgp_privkey_t privkey = NULL;

617

ret = gnutls_openpgp_privkey_init(&privkey);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Error initializing OpenPGP key"

620

" structure: %s", safer_gnutls_strerror(ret));

621

free(buffer.data);

622

buffer.data = NULL;

623

} else {

624

ret = gnutls_openpgp_privkey_import(privkey, &buffer,

625

GNUTLS_OPENPGP_FMT_BASE64,

626

"", 0);

627

if(ret != GNUTLS_E_SUCCESS){

628

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

629

safer_gnutls_strerror(ret));

630

privkey = NULL;

631

}

632

free(buffer.data);

633

buffer.data = NULL;

634

if(privkey != NULL){

635

/* Use private key to suggest an appropriate sec_param */

636

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

637

gnutls_openpgp_privkey_deinit(privkey);

638

if(debug){

639

fprintf_plus(stderr, "This OpenPGP key implies using a"

640

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

641

safe_string(gnutls_sec_param_get_name

642

(sec_param)));

643

}

644

}

645

}

646

}

647

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

648

/* Err on the side of caution */

649

sec_param = GNUTLS_SEC_PARAM_ULTRA;

650

if(debug){

651

fprintf_plus(stderr, "Falling back to security parameter"

652

" \"%s\"\n",

653

safe_string(gnutls_sec_param_get_name

654

(sec_param)));

655

}

656

}

657

}

658

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

659

if(uret != 0){

660

mc->dh_bits = uret;

661

if(debug){

662

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

663

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

664

safe_string(gnutls_sec_param_get_name

665

(sec_param)),

666

mc->dh_bits);

667

}

668

} else {

669

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

670

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

671

safe_string(gnutls_sec_param_get_name(sec_param)),

672

safer_gnutls_strerror(ret));

673

goto globalfail;

674

}

675

} else if(debug){

676

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

677

mc->dh_bits);

678

}

679

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

461

680

if(ret != GNUTLS_E_SUCCESS){

462

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

463

safer_gnutls_strerror(ret));

681

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

682

" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));

464

683

goto globalfail;

465

684

}

466

685

467

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

686

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

468

687

469

688

return 0;

470

689

471

690

globalfail:

472

691

473

gnutls_certificate_free_credentials(mc.cred);

692

gnutls_certificate_free_credentials(mc->cred);

474

693

gnutls_global_deinit();

475

gnutls_dh_params_deinit(mc.dh_params);

694

gnutls_dh_params_deinit(mc->dh_params);

476

695

return -1;

477

696

}

478

697

479

static int init_gnutls_session(gnutls_session_t *session){

698

__attribute__((nonnull, warn_unused_result))

699

static int init_gnutls_session(gnutls_session_t *session,

700

mandos_context *mc){

480

701

int ret;

481

702

/* GnuTLS session creation */

482

703

do {

486

707

}

487

708

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

488

709

if(ret != GNUTLS_E_SUCCESS){

489

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

490

safer_gnutls_strerror(ret));

710

fprintf_plus(stderr,

711

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

712

safer_gnutls_strerror(ret));

491

713

}

492

714

493

715

{

494

716

const char *err;

495

717

do {

496

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

718

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

497

719

if(quit_now){

498

720

gnutls_deinit(*session);

499

721

return -1;

500

722

}

501

723

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

502

724

if(ret != GNUTLS_E_SUCCESS){

503

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

504

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

505

safer_gnutls_strerror(ret));

725

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

726

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

727

safer_gnutls_strerror(ret));

506

728

gnutls_deinit(*session);

507

729

return -1;

508

730

}

510

732

511

733

do {

512

734

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

513

mc.cred);

735

mc->cred);

514

736

if(quit_now){

515

737

gnutls_deinit(*session);

516

738

return -1;

517

739

}

518

740

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

519

741

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

742

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

743

safer_gnutls_strerror(ret));

522

744

gnutls_deinit(*session);

523

745

return -1;

524

746

}

526

748

/* ignore client certificate if any. */

527

749

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

528

750

529

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

751

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

530

752

531

753

return 0;

532

754

}

536

758

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

537

759

538

760

/* Called when a Mandos server is found */

539

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

761

__attribute__((nonnull, warn_unused_result))

762

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

540

763

AvahiIfIndex if_index,

541

int af){

764

int af, mandos_context *mc){

542

765

int ret, tcp_sd = -1;

543

766

ssize_t sret;

544

union {

545

struct sockaddr_in in;

546

struct sockaddr_in6 in6;

547

} to;

767

struct sockaddr_storage to;

548

768

char *buffer = NULL;

549

769

char *decrypted_buffer = NULL;

550

770

size_t buffer_length = 0;

569

789

pf = PF_INET;

570

790

break;

571

791

default:

572

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

792

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

573

793

errno = EINVAL;

574

794

return -1;

575

795

}

576

796

577

ret = init_gnutls_session(&session);

797

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

798

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

799

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

800

bool match = false;

801

{

802

char *interface = NULL;

803

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

804

interface))){

805

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

806

match = true;

807

break;

808

}

809

}

810

}

811

if(not match){

812

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

813

connect to the server */

814

if(debug){

815

char interface[IF_NAMESIZE];

816

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

817

perror_plus("if_indextoname");

818

} else {

819

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

820

" \"%s\"\n",

821

if_indextoname((unsigned int)if_index,

822

interface));

823

}

824

}

825

return -1;

826

}

827

}

828

829

ret = init_gnutls_session(&session, mc);

578

830

if(ret != 0){

579

831

return -1;

580

832

}

581

833

582

834

if(debug){

583

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

584

"\n", ip, port);

835

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

836

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

585

837

}

586

838

587

839

tcp_sd = socket(pf, SOCK_STREAM, 0);

588

840

if(tcp_sd < 0){

589

841

int e = errno;

590

perror("socket");

842

perror_plus("socket");

591

843

errno = e;

592

844

goto mandos_end;

593

845

}

599

851

600

852

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

601

853

if(af == AF_INET6){

602

to.in6.sin6_family = (sa_family_t)af;

603

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

854

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

855

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

604

856

} else { /* IPv4 */

605

to.in.sin_family = (sa_family_t)af;

606

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

857

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

858

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

607

859

}

608

860

if(ret < 0 ){

609

861

int e = errno;

610

perror("inet_pton");

862

perror_plus("inet_pton");

611

863

errno = e;

612

864

goto mandos_end;

613

865

}

614

866

if(ret == 0){

615

867

int e = errno;

616

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

868

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

617

869

errno = e;

618

870

goto mandos_end;

619

871

}

620

872

if(af == AF_INET6){

621

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

622

-Wconversion and

623

-Wunreachable-code */

624

625

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

626

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

627

-Wunreachable-code*/

873

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

874

if(IN6_IS_ADDR_LINKLOCAL

875

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

628

876

if(if_index == AVAHI_IF_UNSPEC){

629

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

630

" without a network interface\n");

877

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

878

" incomplete without a network interface\n");

631

879

errno = EINVAL;

632

880

goto mandos_end;

633

881

}

634

882

/* Set the network interface number as scope */

635

to.in6.sin6_scope_id = (uint32_t)if_index;

883

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

636

884

}

637

885

} else {

638

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

639

-Wconversion and

640

-Wunreachable-code */

886

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

641

887

}

642

888

643

889

if(quit_now){

649

895

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

650

896

char interface[IF_NAMESIZE];

651

897

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

652

perror("if_indextoname");

898

perror_plus("if_indextoname");

653

899

} else {

654

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

655

ip, interface, port);

900

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

901

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

656

902

}

657

903

} else {

658

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

659

port);

904

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

905

ip, (uintmax_t)port);

660

906

}

661

907

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

662

908

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

663

const char *pcret;

664

909

if(af == AF_INET6){

665

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

666

sizeof(addrstr));

910

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

911

sizeof(struct sockaddr_in6),

912

addrstr, sizeof(addrstr), NULL, 0,

913

NI_NUMERICHOST);

667

914

} else {

668

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

669

sizeof(addrstr));

915

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

916

sizeof(struct sockaddr_in),

917

addrstr, sizeof(addrstr), NULL, 0,

918

NI_NUMERICHOST);

670

919

}

671

if(pcret == NULL){

672

perror("inet_ntop");

673

} else {

674

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

675

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

676

}

920

if(ret == EAI_SYSTEM){

921

perror_plus("getnameinfo");

922

} else if(ret != 0) {

923

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

924

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

925

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

677

926

}

678

927

}

679

928

683

932

}

684

933

685

934

if(af == AF_INET6){

686

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

935

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

936

sizeof(struct sockaddr_in6));

687

937

} else {

688

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

938

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

939

sizeof(struct sockaddr_in));

689

940

}

690

941

if(ret < 0){

691

int e = errno;

692

perror("connect");

693

errno = e;

942

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

943

int e = errno;

944

perror_plus("connect");

945

errno = e;

946

}

694

947

goto mandos_end;

695

948

}

696

949

704

957

while(true){

705

958

size_t out_size = strlen(out);

706

959

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

707

out_size - written));

960

out_size - written));

708

961

if(ret == -1){

709

962

int e = errno;

710

perror("write");

963

perror_plus("write");

711

964

errno = e;

712

965

goto mandos_end;

713

966

}

730

983

}

731

984

732

985

if(debug){

733

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

986

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

734

987

}

735

988

736

989

if(quit_now){

738

991

goto mandos_end;

739

992

}

740

993

741

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

994

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

995

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

996

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

997

gnutls_transport_set_ptr(session,

998

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

742

999

743

1000

if(quit_now){

744

1001

errno = EINTR;

755

1012

756

1013

if(ret != GNUTLS_E_SUCCESS){

757

1014

if(debug){

758

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

1015

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

759

1016

gnutls_perror(ret);

760

1017

}

761

1018

errno = EPROTO;

765

1022

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

766

1023

767

1024

if(debug){

768

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

769

ip);

1025

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1026

" %s\n", ip);

770

1027

}

771

1028

772

1029

while(true){

777

1034

}

778

1035

779

1036

buffer_capacity = incbuffer(&buffer, buffer_length,

780

buffer_capacity);

1037

buffer_capacity);

781

1038

if(buffer_capacity == 0){

782

1039

int e = errno;

783

perror("incbuffer");

1040

perror_plus("incbuffer");

784

1041

errno = e;

785

1042

goto mandos_end;

786

1043

}

810

1067

}

811

1068

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

812

1069

if(ret < 0){

813

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

1070

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

1071

"***\n");

814

1072

gnutls_perror(ret);

815

1073

errno = EPROTO;

816

1074

goto mandos_end;

817

1075

}

818

1076

break;

819

1077

default:

820

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

821

" encrypted session with Mandos server\n");

1078

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

1079

" encrypted session with Mandos server\n");

822

1080

gnutls_bye(session, GNUTLS_SHUT_RDWR);

823

1081

errno = EIO;

824

1082

goto mandos_end;

829

1087

}

830

1088

831

1089

if(debug){

832

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

1090

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

833

1091

}

834

1092

835

1093

if(quit_now){

847

1105

848

1106

if(buffer_length > 0){

849

1107

ssize_t decrypted_buffer_size;

850

decrypted_buffer_size = pgp_packet_decrypt(buffer,

851

buffer_length,

852

&decrypted_buffer);

1108

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1109

&decrypted_buffer, mc);

853

1110

if(decrypted_buffer_size >= 0){

854

1111

855

1112

written = 0;

865

1122

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

866

1123

int e = errno;

867

1124

if(debug){

868

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

869

strerror(errno));

1125

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

1126

strerror(errno));

870

1127

}

871

1128

errno = e;

872

1129

goto mandos_end;

891

1148

if(e == 0){

892

1149

e = errno;

893

1150

}

894

perror("close");

1151

perror_plus("close");

895

1152

}

896

1153

gnutls_deinit(session);

1154

errno = e;

897

1155

if(quit_now){

898

e = EINTR;

1156

errno = EINTR;

899

1157

retval = -1;

900

1158

}

901

errno = e;

902

1159

}

903

1160

return retval;

904

1161

}

905

1162

1163

__attribute__((nonnull))

906

1164

static void resolve_callback(AvahiSServiceResolver *r,

907

1165

AvahiIfIndex interface,

908

1166

AvahiProtocol proto,

916

1174

AVAHI_GCC_UNUSED AvahiStringList *txt,

917

1175

AVAHI_GCC_UNUSED AvahiLookupResultFlags

918

1176

flags,

919

AVAHI_GCC_UNUSED void* userdata){

920

assert(r);

1177

void *mc){

1178

if(r == NULL){

1179

return;

1180

}

921

1181

922

1182

/* Called whenever a service has been resolved successfully or

923

1183

timed out */

924

1184

925

1185

if(quit_now){

1186

avahi_s_service_resolver_free(r);

926

1187

return;

927

1188

}

928

1189

929

1190

switch(event){

930

1191

default:

931

1192

case AVAHI_RESOLVER_FAILURE:

932

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

933

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

934

avahi_strerror(avahi_server_errno(mc.server)));

1193

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

1194

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

1195

domain,

1196

avahi_strerror(avahi_server_errno

1197

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

935

1198

break;

936

1199

937

1200

case AVAHI_RESOLVER_FOUND:

939

1202

char ip[AVAHI_ADDRESS_STR_MAX];

940

1203

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

941

1204

if(debug){

942

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

943

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

944

ip, (intmax_t)interface, port);

1205

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

1206

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

1207

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

945

1208

}

946

int ret = start_mandos_communication(ip, port, interface,

947

avahi_proto_to_af(proto));

1209

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

1210

interface,

1211

avahi_proto_to_af(proto),

1212

mc);

948

1213

if(ret == 0){

949

avahi_simple_poll_quit(mc.simple_poll);

1214

avahi_simple_poll_quit(simple_poll);

1215

} else {

1216

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

1217

avahi_proto_to_af(proto),

1218

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

1219

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

1220

" list\n", name);

1221

}

950

1222

}

951

1223

}

952

1224

}

962

1234

const char *domain,

963

1235

AVAHI_GCC_UNUSED AvahiLookupResultFlags

964

1236

flags,

965

AVAHI_GCC_UNUSED void* userdata){

966

assert(b);

1237

void *mc){

1238

if(b == NULL){

1239

return;

1240

}

967

1241

968

1242

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

969

1243

is removed from the LAN */

976

1250

default:

977

1251

case AVAHI_BROWSER_FAILURE:

978

1252

979

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

980

avahi_strerror(avahi_server_errno(mc.server)));

981

avahi_simple_poll_quit(mc.simple_poll);

1253

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

1254

avahi_strerror(avahi_server_errno

1255

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

1256

avahi_simple_poll_quit(simple_poll);

982

1257

return;

983

1258

984

1259

case AVAHI_BROWSER_NEW:

987

1262

the callback function is called the Avahi server will free the

988

1263

resolver for us. */

989

1264

990

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

991

name, type, domain, protocol, 0,

992

resolve_callback, NULL) == NULL)

993

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

994

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

1265

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

1266

interface, protocol, name, type,

1267

domain, protocol, 0,

1268

resolve_callback, mc) == NULL)

1269

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

1270

" %s\n", name,

1271

avahi_strerror(avahi_server_errno

1272

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

995

1273

break;

996

1274

997

1275

case AVAHI_BROWSER_REMOVE:

1000

1278

case AVAHI_BROWSER_ALL_FOR_NOW:

1001

1279

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1002

1280

if(debug){

1003

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

1281

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

1282

" searching...\n");

1004

1283

}

1005

1284

break;

1006

1285

}

1007

1286

}

1008

1287

1009

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

1288

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

1010

1289

static void handle_sigterm(int sig){

1011

1290

if(quit_now){

1012

1291

return;

1014

1293

quit_now = 1;

1015

1294

signal_received = sig;

1016

1295

int old_errno = errno;

1017

if(mc.simple_poll != NULL){

1018

avahi_simple_poll_quit(mc.simple_poll);

1019

}

1020

errno = old_errno;

1296

/* set main loop to exit */

1297

if(simple_poll != NULL){

1298

avahi_simple_poll_quit(simple_poll);

1299

}

1300

errno = old_errno;

1301

}

1302

1303

__attribute__((nonnull, warn_unused_result))

1304

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

1305

int ret;

1306

error_t ret_errno;

1307

1308

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

1309

if(s < 0){

1310

ret_errno = errno;

1311

perror_plus("socket");

1312

errno = ret_errno;

1313

return false;

1314

}

1315

strcpy(ifr->ifr_name, ifname);

1316

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1317

if(ret == -1){

1318

if(debug){

1319

ret_errno = errno;

1320

perror_plus("ioctl SIOCGIFFLAGS");

1321

errno = ret_errno;

1322

}

1323

return false;

1324

}

1325

return true;

1326

}

1327

1328

__attribute__((nonnull, warn_unused_result))

1329

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

1330

1331

/* Reject the loopback device */

1332

if(ifr->ifr_flags & IFF_LOOPBACK){

1333

if(debug){

1334

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

1335

ifname);

1336

}

1337

return false;

1338

}

1339

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

1340

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

1341

if(debug){

1342

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

1343

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

1344

}

1345

return true;

1346

}

1347

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

1348

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

1349

if(debug){

1350

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1351

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

1352

}

1353

return false;

1354

}

1355

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

1356

if(ifr->ifr_flags & IFF_NOARP){

1357

if(debug){

1358

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

1359

ifname);

1360

}

1361

return false;

1362

}

1363

1364

/* Accept this device */

1365

if(debug){

1366

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

1367

}

1368

return true;

1369

}

1370

1371

/*

1372

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

1373

* corresponds to an acceptable network device.

1374

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

1375

*/

1376

__attribute__((nonnull, warn_unused_result))

1377

int good_interface(const struct dirent *if_entry){

1378

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

1379

return 0;

1380

}

1381

1382

struct ifreq ifr;

1383

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

1384

if(debug){

1385

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

1386

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

1387

}

1388

return 0;

1389

}

1390

1391

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

1392

return 0;

1393

}

1394

return 1;

1395

}

1396

1397

/*

1398

* This function determines if a network interface is up.

1399

*/

1400

__attribute__((nonnull, warn_unused_result))

1401

bool interface_is_up(const char *interface){

1402

struct ifreq ifr;

1403

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

1404

if(debug){

1405

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

1406

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

1407

}

1408

return false;

1409

}

1410

1411

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

1412

}

1413

1414

/*

1415

* This function determines if a network interface is running

1416

*/

1417

__attribute__((nonnull, warn_unused_result))

1418

bool interface_is_running(const char *interface){

1419

struct ifreq ifr;

1420

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

1421

if(debug){

1422

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

1423

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

1424

}

1425

return false;

1426

}

1427

1428

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

1429

}

1430

1431

__attribute__((nonnull, pure, warn_unused_result))

1432

int notdotentries(const struct dirent *direntry){

1433

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

1434

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

1435

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

1436

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

1437

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

1438

return 0;

1439

}

1440

return 1;

1441

}

1442

1443

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

1444

__attribute__((nonnull, warn_unused_result))

1445

int runnable_hook(const struct dirent *direntry){

1446

int ret;

1447

size_t sret;

1448

struct stat st;

1449

1450

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

1451

/* Empty name? */

1452

return 0;

1453

}

1454

1455

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

1456

"abcdefghijklmnopqrstuvwxyz"

1457

"0123456789"

1458

"_.-");

1459

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

1460

/* Contains non-allowed characters */

1461

if(debug){

1462

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

1463

direntry->d_name);

1464

}

1465

return 0;

1466

}

1467

1468

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

1469

if(ret == -1){

1470

if(debug){

1471

perror_plus("Could not stat hook");

1472

}

1473

return 0;

1474

}

1475

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

1476

/* Not a regular file */

1477

if(debug){

1478

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

1479

direntry->d_name);

1480

}

1481

return 0;

1482

}

1483

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

1484

/* Not executable */

1485

if(debug){

1486

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

1487

direntry->d_name);

1488

}

1489

return 0;

1490

}

1491

if(debug){

1492

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

1493

direntry->d_name);

1494

}

1495

return 1;

1496

}

1497

1498

__attribute__((nonnull, warn_unused_result))

1499

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1500

mandos_context *mc){

1501

int ret;

1502

struct timespec now;

1503

struct timespec waited_time;

1504

intmax_t block_time;

1505

1506

while(true){

1507

if(mc->current_server == NULL){

1508

if(debug){

1509

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

1510

" No timeout!\n");

1511

}

1512

ret = avahi_simple_poll_iterate(s, -1);

1513

} else {

1514

if(debug){

1515

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

1516

" it, or wait\n");

1517

}

1518

/* the current time */

1519

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1520

if(ret == -1){

1521

perror_plus("clock_gettime");

1522

return -1;

1523

}

1524

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

1525

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

1526

waited_time.tv_sec = (now.tv_sec

1527

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

1528

waited_time.tv_nsec = (now.tv_nsec

1529

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

1530

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

1531

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

1532

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

1533

block_time = ((retry_interval

1534

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

1535

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

1536

1537

if(debug){

1538

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

1539

block_time);

1540

}

1541

1542

if(block_time <= 0){

1543

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

1544

mc->current_server->port,

1545

mc->current_server->if_index,

1546

mc->current_server->af, mc);

1547

if(ret == 0){

1548

avahi_simple_poll_quit(s);

1549

return 0;

1550

}

1551

ret = clock_gettime(CLOCK_MONOTONIC,

1552

&mc->current_server->last_seen);

1553

if(ret == -1){

1554

perror_plus("clock_gettime");

1555

return -1;

1556

}

1557

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

1558

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

1559

servers, but don't block */

1560

}

1561

1562

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

1563

}

1564

if(ret != 0){

1565

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

1566

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

1567

}

1568

}

1569

}

1570

}

1571

1572

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

1573

__attribute__((warn_unused_result))

1574

error_t raise_privileges(void){

1575

error_t old_errno = errno;

1576

error_t ret_errno = 0;

1577

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

1578

ret_errno = errno;

1579

}

1580

errno = old_errno;

1581

return ret_errno;

1582

}

1583

1584

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

1585

__attribute__((warn_unused_result))

1586

error_t raise_privileges_permanently(void){

1587

error_t old_errno = errno;

1588

error_t ret_errno = raise_privileges();

1589

if(ret_errno != 0){

1590

errno = old_errno;

1591

return ret_errno;

1592

}

1593

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

1594

ret_errno = errno;

1595

}

1596

errno = old_errno;

1597

return ret_errno;

1598

}

1599

1600

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

1601

__attribute__((warn_unused_result))

1602

error_t lower_privileges(void){

1603

error_t old_errno = errno;

1604

error_t ret_errno = 0;

1605

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

1606

ret_errno = errno;

1607

}

1608

errno = old_errno;

1609

return ret_errno;

1610

}

1611

1612

/* Lower privileges permanently */

1613

__attribute__((warn_unused_result))

1614

error_t lower_privileges_permanently(void){

1615

error_t old_errno = errno;

1616

error_t ret_errno = 0;

1617

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

1618

ret_errno = errno;

1619

}

1620

errno = old_errno;

1621

return ret_errno;

1622

}

1623

1624

__attribute__((nonnull))

1625

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

1626

const float delay){

1627

struct dirent **direntries = NULL;

1628

if(hookdir_fd == -1){

1629

hookdir_fd = open(hookdir, O_RDONLY);

1630

if(hookdir_fd == -1){

1631

if(errno == ENOENT){

1632

if(debug){

1633

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

1634

" found\n", hookdir);

1635

}

1636

} else {

1637

perror_plus("open");

1638

}

1639

return;

1640

}

1641

}

1642

#ifdef __GLIBC__

1643

#if __GLIBC_PREREQ(2, 15)

1644

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

1645

runnable_hook, alphasort);

1646

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

1647

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

1648

alphasort);

1649

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

1650

#else /* not __GLIBC__ */

1651

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

1652

alphasort);

1653

#endif /* not __GLIBC__ */

1654

if(numhooks == -1){

1655

perror_plus("scandir");

1656

return;

1657

}

1658

struct dirent *direntry;

1659

int ret;

1660

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

1661

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

1662

direntry = direntries[i];

1663

if(debug){

1664

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

1665

direntry->d_name);

1666

}

1667

pid_t hook_pid = fork();

1668

if(hook_pid == 0){

1669

/* Child */

1670

/* Raise privileges */

1671

errno = raise_privileges_permanently();

1672

if(errno != 0){

1673

perror_plus("Failed to raise privileges");

1674

_exit(EX_NOPERM);

1675

}

1676

/* Set group */

1677

errno = 0;

1678

ret = setgid(0);

1679

if(ret == -1){

1680

perror_plus("setgid");

1681

_exit(EX_NOPERM);

1682

}

1683

/* Reset supplementary groups */

1684

errno = 0;

1685

ret = setgroups(0, NULL);

1686

if(ret == -1){

1687

perror_plus("setgroups");

1688

_exit(EX_NOPERM);

1689

}

1690

ret = dup2(devnull, STDIN_FILENO);

1691

if(ret == -1){

1692

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

1693

_exit(EX_OSERR);

1694

}

1695

ret = close(devnull);

1696

if(ret == -1){

1697

perror_plus("close");

1698

_exit(EX_OSERR);

1699

}

1700

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1701

if(ret == -1){

1702

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

1703

_exit(EX_OSERR);

1704

}

1705

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

1706

if(ret == -1){

1707

perror_plus("setenv");

1708

_exit(EX_OSERR);

1709

}

1710

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

1711

if(ret == -1){

1712

perror_plus("setenv");

1713

_exit(EX_OSERR);

1714

}

1715

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

1716

if(ret == -1){

1717

perror_plus("setenv");

1718

_exit(EX_OSERR);

1719

}

1720

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

1721

if(ret == -1){

1722

perror_plus("setenv");

1723

_exit(EX_OSERR);

1724

}

1725

char *delaystring;

1726

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

1727

if(ret == -1){

1728

perror_plus("asprintf");

1729

_exit(EX_OSERR);

1730

}

1731

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

1732

if(ret == -1){

1733

free(delaystring);

1734

perror_plus("setenv");

1735

_exit(EX_OSERR);

1736

}

1737

free(delaystring);

1738

if(connect_to != NULL){

1739

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

1740

if(ret == -1){

1741

perror_plus("setenv");

1742

_exit(EX_OSERR);

1743

}

1744

}

1745

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1746

if(hook_fd == -1){

1747

perror_plus("openat");

1748

_exit(EXIT_FAILURE);

1749

}

1750

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

1751

perror_plus("close");

1752

_exit(EXIT_FAILURE);

1753

}

1754

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

1755

environ) == -1){

1756

perror_plus("fexecve");

1757

_exit(EXIT_FAILURE);

1758

}

1759

} else {

1760

if(hook_pid == -1){

1761

perror_plus("fork");

1762

free(direntry);

1763

continue;

1764

}

1765

int status;

1766

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

1767

perror_plus("waitpid");

1768

free(direntry);

1769

continue;

1770

}

1771

if(WIFEXITED(status)){

1772

if(WEXITSTATUS(status) != 0){

1773

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

1774

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

1775

WEXITSTATUS(status));

1776

free(direntry);

1777

continue;

1778

}

1779

} else if(WIFSIGNALED(status)){

1780

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

1781

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

1782

WTERMSIG(status));

1783

free(direntry);

1784

continue;

1785

} else {

1786

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

1787

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

1788

free(direntry);

1789

continue;

1790

}

1791

}

1792

if(debug){

1793

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

1794

direntry->d_name);

1795

}

1796

free(direntry);

1797

}

1798

free(direntries);

1799

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

1800

perror_plus("close");

1801

} else {

1802

hookdir_fd = -1;

1803

}

1804

close(devnull);

1805

}

1806

1807

__attribute__((nonnull, warn_unused_result))

1808

error_t bring_up_interface(const char *const interface,

1809

const float delay){

1810

error_t old_errno = errno;

1811

int ret;

1812

struct ifreq network;

1813

unsigned int if_index = if_nametoindex(interface);

1814

if(if_index == 0){

1815

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

1816

errno = old_errno;

1817

return ENXIO;

1818

}

1819

1820

if(quit_now){

1821

errno = old_errno;

1822

return EINTR;

1823

}

1824

1825

if(not interface_is_up(interface)){

1826

error_t ret_errno = 0, ioctl_errno = 0;

1827

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

1828

ret_errno = errno;

1829

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

1830

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

1831

errno = old_errno;

1832

return ret_errno;

1833

}

1834

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

1835

1836

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

1837

if(sd == -1){

1838

ret_errno = errno;

1839

perror_plus("socket");

1840

errno = old_errno;

1841

return ret_errno;

1842

}

1843

1844

if(quit_now){

1845

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

1846

if(ret == -1){

1847

perror_plus("close");

1848

}

1849

errno = old_errno;

1850

return EINTR;

1851

}

1852

1853

if(debug){

1854

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

1855

interface);

1856

}

1857

1858

/* Raise privileges */

1859

ret_errno = raise_privileges();

1860

if(ret_errno != 0){

1861

errno = ret_errno;

1862

perror_plus("Failed to raise privileges");

1863

}

1864

1865

#ifdef __linux__

1866

int ret_linux;

1867

bool restore_loglevel = false;

1868

if(ret_errno == 0){

1869

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1870

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

1871

ret_linux = klogctl(8, NULL, 5);

1872

if(ret_linux == -1){

1873

perror_plus("klogctl");

1874

} else {

1875

restore_loglevel = true;

1876

}

1877

}

1878

#endif /* __linux__ */

1879

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

1880

ioctl_errno = errno;

1881

#ifdef __linux__

1882

if(restore_loglevel){

1883

ret_linux = klogctl(7, NULL, 0);

1884

if(ret_linux == -1){

1885

perror_plus("klogctl");

1886

}

1887

}

1888

#endif /* __linux__ */

1889

1890

/* If raise_privileges() succeeded above */

1891

if(ret_errno == 0){

1892

/* Lower privileges */

1893

ret_errno = lower_privileges();

1894

if(ret_errno != 0){

1895

errno = ret_errno;

1896

perror_plus("Failed to lower privileges");

1897

}

1898

}

1899

1900

/* Close the socket */

1901

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

1902

if(ret == -1){

1903

perror_plus("close");

1904

}

1905

1906

if(ret_setflags == -1){

1907

errno = ioctl_errno;

1908

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1909

errno = old_errno;

1910

return ioctl_errno;

1911

}

1912

} else if(debug){

1913

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

1914

interface);

1915

}

1916

1917

/* Sleep checking until interface is running.

1918

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

1919

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

1920

if(interface_is_running(interface)){

1921

break;

1922

}

1923

struct timespec sleeptime = { .tv_nsec = 250000000 };

1924

ret = nanosleep(&sleeptime, NULL);

1925

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

1926

perror_plus("nanosleep");

1927

}

1928

}

1929

1930

errno = old_errno;

1931

return 0;

1932

}

1933

1934

__attribute__((nonnull, warn_unused_result))

1935

error_t take_down_interface(const char *const interface){

1936

error_t old_errno = errno;

1937

struct ifreq network;

1938

unsigned int if_index = if_nametoindex(interface);

1939

if(if_index == 0){

1940

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

1941

errno = old_errno;

1942

return ENXIO;

1943

}

1944

if(interface_is_up(interface)){

1945

error_t ret_errno = 0, ioctl_errno = 0;

1946

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

1947

ret_errno = errno;

1948

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

1949

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

1950

errno = old_errno;

1951

return ret_errno;

1952

}

1953

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

1954

1955

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

1956

if(sd == -1){

1957

ret_errno = errno;

1958

perror_plus("socket");

1959

errno = old_errno;

1960

return ret_errno;

1961

}

1962

1963

if(debug){

1964

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

1965

interface);

1966

}

1967

1968

/* Raise privileges */

1969

ret_errno = raise_privileges();

1970

if(ret_errno != 0){

1971

errno = ret_errno;

1972

perror_plus("Failed to raise privileges");

1973

}

1974

1975

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

1976

ioctl_errno = errno;

1977

1978

/* If raise_privileges() succeeded above */

1979

if(ret_errno == 0){

1980

/* Lower privileges */

1981

ret_errno = lower_privileges();

1982

if(ret_errno != 0){

1983

errno = ret_errno;

1984

perror_plus("Failed to lower privileges");

1985

}

1986

}

1987

1988

/* Close the socket */

1989

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

1990

if(ret == -1){

1991

perror_plus("close");

1992

}

1993

1994

if(ret_setflags == -1){

1995

errno = ioctl_errno;

1996

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1997

errno = old_errno;

1998

return ioctl_errno;

1999

}

2000

} else if(debug){

2001

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

2002

interface);

2003

}

2004

2005

errno = old_errno;

2006

return 0;

1021

2007

}

1022

2008

1023

2009

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

2010

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

2011

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

2012

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

2013

.interfaces = NULL, .interfaces_size = 0 };

1024

2014

AvahiSServiceBrowser *sb = NULL;

1025

int error;

2015

error_t ret_errno;

1026

2016

int ret;

1027

2017

intmax_t tmpmax;

1028

2018

char *tmp;

1029

2019

int exitcode = EXIT_SUCCESS;

1030

const char *interface = "eth0";

1031

struct ifreq network;

1032

int sd = -1;

1033

bool take_down_interface = false;

1034

uid_t uid;

1035

gid_t gid;

1036

char *connect_to = NULL;

1037

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

1038

bool tempdir_created = false;

2020

char *interfaces_to_take_down = NULL;

2021

size_t interfaces_to_take_down_size = 0;

2022

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

2023

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

2024

char *tempdir = NULL;

1039

2025

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1040

2026

const char *seckey = PATHDIR "/" SECKEY;

1041

2027

const char *pubkey = PATHDIR "/" PUBKEY;

2028

char *interfaces_hooks = NULL;

1042

2029

1043

2030

bool gnutls_initialized = false;

1044

2031

bool gpgme_initialized = false;

1045

2032

float delay = 2.5f;

2033

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

2034

retrying the same server again */

1046

2035

1047

2036

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1048

2037

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1054

2043

errno = 0;

1055

2044

ret = setgid(gid);

1056

2045

if(ret == -1){

1057

perror("setgid");

2046

perror_plus("setgid");

1058

2047

}

1059

2048

1060

2049

/* Lower user privileges (temporarily) */

1061

2050

errno = 0;

1062

2051

ret = seteuid(uid);

1063

2052

if(ret == -1){

1064

perror("seteuid");

2053

perror_plus("seteuid");

1065

2054

}

1066

2055

1067

2056

if(quit_now){

1102

2091

.arg = "SECONDS",

1103

2092

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

1104

2093

.group = 2 },

2094

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

2095

.arg = "SECONDS",

2096

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

2097

.group = 2 },

2098

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

2099

.arg = "DIR",

2100

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

2101

.group = 2 },

1105

2102

/*

1106

2103

* These reproduce what we would get without ARGP_NO_HELP

1107

2104

*/

1125

2122

connect_to = arg;

1126

2123

break;

1127

2124

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

1128

interface = arg;

2125

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

2126

arg, (int)',');

2127

if(ret_errno != 0){

2128

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

2129

}

1129

2130

break;

1130

2131

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

1131

2132

seckey = arg;

1151

2152

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

1152

2153

argp_error(state, "Bad delay");

1153

2154

}

2155

case 132: /* --retry */

2156

errno = 0;

2157

retry_interval = strtod(arg, &tmp);

2158

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

2159

or (retry_interval * 1000) > INT_MAX

2160

or retry_interval < 0){

2161

argp_error(state, "Bad retry interval");

2162

}

2163

break;

2164

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

2165

hookdir = arg;

1154

2166

break;

1155

2167

/*

1156

2168

* These reproduce what we would get without ARGP_NO_HELP

1163

2175

argp_state_help(state, state->out_stream,

1164

2176

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1165

2177

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

1166

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

2178

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

1167

2179

exit(argp_err_exit_status);

1168

2180

break;

1169

2181

default:

1184

2196

case ENOMEM:

1185

2197

default:

1186

2198

errno = ret;

1187

perror("argp_parse");

2199

perror_plus("argp_parse");

1188

2200

exitcode = EX_OSERR;

1189

2201

goto end;

1190

2202

case EINVAL:

1192

2204

goto end;

1193

2205

}

1194

2206

}

2207

2208

{

2209

/* Work around Debian bug #633582:

2210

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

2211

2212

/* Re-raise privileges */

2213

ret_errno = raise_privileges();

2214

if(ret_errno != 0){

2215

errno = ret_errno;

2216

perror_plus("Failed to raise privileges");

2217

} else {

2218

struct stat st;

2219

2220

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

2221

int seckey_fd = open(seckey, O_RDONLY);

2222

if(seckey_fd == -1){

2223

perror_plus("open");

2224

} else {

2225

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

2226

if(ret == -1){

2227

perror_plus("fstat");

2228

} else {

2229

if(S_ISREG(st.st_mode)

2230

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

2231

ret = fchown(seckey_fd, uid, gid);

2232

if(ret == -1){

2233

perror_plus("fchown");

2234

}

2235

}

2236

}

2237

TEMP_FAILURE_RETRY(close(seckey_fd));

2238

}

2239

}

2240

2241

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

2242

int pubkey_fd = open(pubkey, O_RDONLY);

2243

if(pubkey_fd == -1){

2244

perror_plus("open");

2245

} else {

2246

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

2247

if(ret == -1){

2248

perror_plus("fstat");

2249

} else {

2250

if(S_ISREG(st.st_mode)

2251

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

2252

ret = fchown(pubkey_fd, uid, gid);

2253

if(ret == -1){

2254

perror_plus("fchown");

2255

}

2256

}

2257

}

2258

TEMP_FAILURE_RETRY(close(pubkey_fd));

2259

}

2260

}

2261

2262

/* Lower privileges */

2263

ret_errno = lower_privileges();

2264

if(ret_errno != 0){

2265

errno = ret_errno;

2266

perror_plus("Failed to lower privileges");

2267

}

2268

}

2269

}

2270

2271

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

2272

{

2273

char *interface = NULL;

2274

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

2275

interface))){

2276

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

2277

and if_nametoindex(interface) == 0){

2278

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

2279

fprintf_plus(stderr, "Not using nonexisting interface"

2280

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

2281

}

2282

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

2283

interface = NULL;

2284

}

2285

}

2286

}

2287

2288

/* Run network hooks */

2289

{

2290

if(mc.interfaces != NULL){

2291

interfaces_hooks = malloc(mc.interfaces_size);

2292

if(interfaces_hooks == NULL){

2293

perror_plus("malloc");

2294

goto end;

2295

}

2296

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

2297

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

2298

}

2299

run_network_hooks("start", interfaces_hooks != NULL ?

2300

interfaces_hooks : "", delay);

2301

}

1195

2302

1196

2303

if(not debug){

1197

2304

avahi_set_log_function(empty_log);

1201

2308

from the signal handler */

1202

2309

/* Initialize the pseudo-RNG for Avahi */

1203

2310

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

1204

mc.simple_poll = avahi_simple_poll_new();

1205

if(mc.simple_poll == NULL){

1206

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

2311

simple_poll = avahi_simple_poll_new();

2312

if(simple_poll == NULL){

2313

fprintf_plus(stderr,

2314

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

1207

2315

exitcode = EX_UNAVAILABLE;

1208

2316

goto end;

1209

2317

}

1211

2319

sigemptyset(&sigterm_action.sa_mask);

1212

2320

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

1213

2321

if(ret == -1){

1214

perror("sigaddset");

2322

perror_plus("sigaddset");

1215

2323

exitcode = EX_OSERR;

1216

2324

goto end;

1217

2325

}

1218

2326

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

1219

2327

if(ret == -1){

1220

perror("sigaddset");

2328

perror_plus("sigaddset");

1221

2329

exitcode = EX_OSERR;

1222

2330

goto end;

1223

2331

}

1224

2332

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

1225

2333

if(ret == -1){

1226

perror("sigaddset");

2334

perror_plus("sigaddset");

1227

2335

exitcode = EX_OSERR;

1228

2336

goto end;

1229

2337

}

1233

2341

*/

1234

2342

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

1235

2343

if(ret == -1){

1236

perror("sigaction");

2344

perror_plus("sigaction");

1237

2345

return EX_OSERR;

1238

2346

}

1239

2347

if(old_sigterm_action.sa_handler != SIG_IGN){

1240

2348

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

1241

2349

if(ret == -1){

1242

perror("sigaction");

2350

perror_plus("sigaction");

1243

2351

exitcode = EX_OSERR;

1244

2352

goto end;

1245

2353

}

1246

2354

}

1247

2355

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

1248

2356

if(ret == -1){

1249

perror("sigaction");

2357

perror_plus("sigaction");

1250

2358

return EX_OSERR;

1251

2359

}

1252

2360

if(old_sigterm_action.sa_handler != SIG_IGN){

1253

2361

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

1254

2362

if(ret == -1){

1255

perror("sigaction");

2363

perror_plus("sigaction");

1256

2364

exitcode = EX_OSERR;

1257

2365

goto end;

1258

2366

}

1259

2367

}

1260

2368

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

1261

2369

if(ret == -1){

1262

perror("sigaction");

2370

perror_plus("sigaction");

1263

2371

return EX_OSERR;

1264

2372

}

1265

2373

if(old_sigterm_action.sa_handler != SIG_IGN){

1266

2374

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

1267

2375

if(ret == -1){

1268

perror("sigaction");

1269

exitcode = EX_OSERR;

1270

goto end;

1271

}

1272

}

1273

1274

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

1275

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

1276

if_index = (AvahiIfIndex) if_nametoindex(interface);

1277

if(if_index == 0){

1278

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

1279

exitcode = EX_UNAVAILABLE;

1280

goto end;

1281

}

1282

1283

if(quit_now){

1284

goto end;

1285

}

1286

1287

/* Re-raise priviliges */

1288

errno = 0;

1289

ret = seteuid(0);

1290

if(ret == -1){

1291

perror("seteuid");

1292

}

1293

1294

#ifdef __linux__

1295

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1296

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

1297

ret = klogctl(8, NULL, 5);

1298

bool restore_loglevel = true;

1299

if(ret == -1){

1300

restore_loglevel = false;

1301

perror("klogctl");

1302

}

1303

#endif /* __linux__ */

1304

1305

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1306

if(sd < 0){

1307

perror("socket");

1308

exitcode = EX_OSERR;

1309

#ifdef __linux__

1310

if(restore_loglevel){

1311

ret = klogctl(7, NULL, 0);

1312

if(ret == -1){

1313

perror("klogctl");

1314

}

1315

}

1316

#endif /* __linux__ */

1317

/* Lower privileges */

1318

errno = 0;

1319

ret = seteuid(uid);

1320

if(ret == -1){

1321

perror("seteuid");

1322

}

1323

goto end;

1324

}

1325

strcpy(network.ifr_name, interface);

1326

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

1327

if(ret == -1){

1328

perror("ioctl SIOCGIFFLAGS");

1329

#ifdef __linux__

1330

if(restore_loglevel){

1331

ret = klogctl(7, NULL, 0);

1332

if(ret == -1){

1333

perror("klogctl");

1334

}

1335

}

1336

#endif /* __linux__ */

1337

exitcode = EX_OSERR;

1338

/* Lower privileges */

1339

errno = 0;

1340

ret = seteuid(uid);

1341

if(ret == -1){

1342

perror("seteuid");

1343

}

1344

goto end;

1345

}

1346

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

1347

network.ifr_flags |= IFF_UP;

1348

take_down_interface = true;

1349

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

1350

if(ret == -1){

1351

take_down_interface = false;

1352

perror("ioctl SIOCSIFFLAGS");

1353

exitcode = EX_OSERR;

1354

#ifdef __linux__

1355

if(restore_loglevel){

1356

ret = klogctl(7, NULL, 0);

1357

if(ret == -1){

1358

perror("klogctl");

2376

perror_plus("sigaction");

2377

exitcode = EX_OSERR;

2378

goto end;

2379

}

2380

}

2381

2382

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

2383

if(mc.interfaces == NULL){

2384

struct dirent **direntries = NULL;

2385

/* Look for any good interfaces */

2386

ret = scandir(sys_class_net, &direntries, good_interface,

2387

alphasort);

2388

if(ret >= 1){

2389

/* Add all found interfaces to interfaces list */

2390

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

2391

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

2392

direntries[i]->d_name);

2393

if(ret_errno != 0){

2394

errno = ret_errno;

2395

perror_plus("argz_add");

2396

free(direntries[i]);

2397

continue;

2398

}

2399

if(debug){

2400

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

2401

direntries[i]->d_name);

2402

}

2403

free(direntries[i]);

2404

}

2405

free(direntries);

2406

} else {

2407

if(ret == 0){

2408

free(direntries);

2409

}

2410

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

2411

exitcode = EXIT_FAILURE;

2412

goto end;

2413

}

2414

}

2415

2416

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

2417

{

2418

char *interface = NULL;

2419

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

2420

interface))){

2421

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

2422

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

2423

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

2424

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

2425

interface);

2426

interface = NULL;

2427

while((interface = argz_next(mc.interfaces,

2428

mc.interfaces_size, interface))){

2429

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

2430

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

2431

interface);

2432

interface = NULL;

1359

2433

}

1360

2434

}

1361

#endif /* __linux__ */

1362

/* Lower privileges */

1363

errno = 0;

1364

ret = seteuid(uid);

1365

if(ret == -1){

1366

perror("seteuid");

1367

}

1368

goto end;

1369

}

1370

}

1371

/* sleep checking until interface is running */

1372

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

1373

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

1374

if(ret == -1){

1375

perror("ioctl SIOCGIFFLAGS");

1376

} else if(network.ifr_flags & IFF_RUNNING){

1377

2435

break;

1378

2436

}

1379

struct timespec sleeptime = { .tv_nsec = 250000000 };

1380

ret = nanosleep(&sleeptime, NULL);

1381

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

1382

perror("nanosleep");

1383

}

1384

}

1385

if(not take_down_interface){

1386

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

1387

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

1388

if(ret == -1){

1389

perror("close");

1390

}

1391

}

1392

#ifdef __linux__

1393

if(restore_loglevel){

1394

/* Restores kernel loglevel to default */

1395

ret = klogctl(7, NULL, 0);

1396

if(ret == -1){

1397

perror("klogctl");

1398

}

1399

}

1400

#endif /* __linux__ */

1401

/* Lower privileges */

1402

errno = 0;

1403

if(take_down_interface){

1404

/* Lower privileges */

1405

ret = seteuid(uid);

1406

if(ret == -1){

1407

perror("seteuid");

1408

}

1409

} else {

1410

/* Lower privileges permanently */

1411

ret = setuid(uid);

1412

if(ret == -1){

1413

perror("setuid");

1414

}

1415

}

2437

bool interface_was_up = interface_is_up(interface);

2438

errno = bring_up_interface(interface, delay);

2439

if(not interface_was_up){

2440

if(errno != 0){

2441

perror_plus("Failed to bring up interface");

2442

} else {

2443

errno = argz_add(&interfaces_to_take_down,

2444

&interfaces_to_take_down_size,

2445

interface);

2446

if(errno != 0){

2447

perror_plus("argz_add");

2448

}

2449

}

2450

}

2451

}

2452

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

2453

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

2454

}

2455

}

2456

2457

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

2458

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

2459

if(debug){

2460

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

2461

mc.interfaces);

2462

}

2463

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

1416

2464

}

1417

2465

1418

2466

if(quit_now){

1419

2467

goto end;

1420

2468

}

1421

2469

1422

ret = init_gnutls_global(pubkey, seckey);

2470

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

1423

2471

if(ret == -1){

1424

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

2472

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

1425

2473

exitcode = EX_UNAVAILABLE;

1426

2474

goto end;

1427

2475

} else {

1432

2480

goto end;

1433

2481

}

1434

2482

1435

tempdir_created = true;

1436

if(mkdtemp(tempdir) == NULL){

1437

tempdir_created = false;

1438

perror("mkdtemp");

2483

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

2484

tempdir = mkdtemp(run_tempdir);

2485

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

2486

if(debug){

2487

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

2488

run_tempdir, old_tempdir);

2489

}

2490

tempdir = mkdtemp(old_tempdir);

2491

}

2492

if(tempdir == NULL){

2493

perror_plus("mkdtemp");

1439

2494

goto end;

1440

2495

}

1441

2496

1443

2498

goto end;

1444

2499

}

1445

2500

1446

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

1447

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

2501

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

2502

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

1448

2503

exitcode = EX_UNAVAILABLE;

1449

2504

goto end;

1450

2505

} else {

1459

2514

/* Connect directly, do not use Zeroconf */

1460

2515

/* (Mainly meant for debugging) */

1461

2516

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

2517

1462

2518

if(address == NULL){

1463

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

2519

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

1464

2520

exitcode = EX_USAGE;

1465

2521

goto end;

1466

2522

}

1469

2525

goto end;

1470

2526

}

1471

2527

1472

uint16_t port;

2528

in_port_t port;

1473

2529

errno = 0;

1474

2530

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

1475

2531

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

1476

or tmpmax != (uint16_t)tmpmax){

1477

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

2532

or tmpmax != (in_port_t)tmpmax){

2533

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

1478

2534

exitcode = EX_USAGE;

1479

2535

goto end;

1480

2536

}

1481

2537

1482

2538

if(quit_now){

1483

2539

goto end;

1484

2540

}

1485

2541

1486

port = (uint16_t)tmpmax;

2542

port = (in_port_t)tmpmax;

1487

2543

*address = '\0';

1488

address = connect_to;

1489

2544

/* Colon in address indicates IPv6 */

1490

2545

int af;

1491

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

2546

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

1492

2547

af = AF_INET6;

2548

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

2549

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

2550

{

2551

connect_to++;

2552

address[-1] = '\0';

2553

}

1493

2554

} else {

1494

2555

af = AF_INET;

1495

2556

}

2557

address = connect_to;

1496

2558

1497

2559

if(quit_now){

1498

2560

goto end;

1499

2561

}

1500

2562

1501

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

1502

if(ret < 0){

1503

switch(errno){

1504

case ENETUNREACH:

1505

case EHOSTDOWN:

1506

case EHOSTUNREACH:

1507

exitcode = EX_NOHOST;

1508

break;

1509

case EINVAL:

1510

exitcode = EX_USAGE;

1511

break;

1512

case EIO:

1513

exitcode = EX_IOERR;

1514

break;

1515

case EPROTO:

1516

exitcode = EX_PROTOCOL;

1517

break;

1518

default:

1519

exitcode = EX_OSERR;

1520

break;

1521

}

1522

} else {

2563

while(not quit_now){

2564

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

2565

&mc);

2566

if(quit_now or ret == 0){

2567

break;

2568

}

2569

if(debug){

2570

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

2571

(int)retry_interval);

2572

}

2573

sleep((unsigned int)retry_interval);

2574

}

2575

2576

if(not quit_now){

1523

2577

exitcode = EXIT_SUCCESS;

1524

2578

}

2579

1525

2580

goto end;

1526

2581

}

1527

2582

1539

2594

config.publish_domain = 0;

1540

2595

1541

2596

/* Allocate a new server */

1542

mc.server = avahi_server_new(avahi_simple_poll_get

1543

(mc.simple_poll), &config, NULL,

1544

NULL, &error);

2597

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2598

&config, NULL, NULL, &ret_errno);

1545

2599

1546

2600

/* Free the Avahi configuration data */

1547

2601

avahi_server_config_free(&config);

1549

2603

1550

2604

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

1551

2605

if(mc.server == NULL){

1552

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

1553

avahi_strerror(error));

2606

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

2607

avahi_strerror(ret_errno));

1554

2608

exitcode = EX_UNAVAILABLE;

1555

2609

goto end;

1556

2610

}

1562

2616

/* Create the Avahi service browser */

1563

2617

sb = avahi_s_service_browser_new(mc.server, if_index,

1564

2618

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1565

NULL, 0, browse_callback, NULL);

2619

NULL, 0, browse_callback,

2620

(void *)&mc);

1566

2621

if(sb == NULL){

1567

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

1568

avahi_strerror(avahi_server_errno(mc.server)));

2622

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

2623

avahi_strerror(avahi_server_errno(mc.server)));

1569

2624

exitcode = EX_UNAVAILABLE;

1570

2625

goto end;

1571

2626

}

1577

2632

/* Run the main loop */

1578

2633

1579

2634

if(debug){

1580

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

2635

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

1581

2636

}

1582

2637

1583

avahi_simple_poll_loop(mc.simple_poll);

2638

ret = avahi_loop_with_timeout(simple_poll,

2639

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

2640

if(debug){

2641

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

2642

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

2643

}

1584

2644

1585

2645

end:

1586

2646

1587

2647

if(debug){

1588

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

2648

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

1589

2649

}

1590

2650

1591

2651

/* Cleanup things */

2652

free(mc.interfaces);

2653

1592

2654

if(sb != NULL)

1593

2655

avahi_s_service_browser_free(sb);

1594

2656

1595

2657

if(mc.server != NULL)

1596

2658

avahi_server_free(mc.server);

1597

2659

1598

if(mc.simple_poll != NULL)

1599

avahi_simple_poll_free(mc.simple_poll);

2660

if(simple_poll != NULL)

2661

avahi_simple_poll_free(simple_poll);

1600

2662

1601

2663

if(gnutls_initialized){

1602

2664

gnutls_certificate_free_credentials(mc.cred);

1608

2670

gpgme_release(mc.ctx);

1609

2671

}

1610

2672

1611

/* Take down the network interface */

1612

if(take_down_interface){

1613

/* Re-raise priviliges */

1614

errno = 0;

1615

ret = seteuid(0);

1616

if(ret == -1){

1617

perror("seteuid");

1618

}

1619

if(geteuid() == 0){

1620

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

1621

if(ret == -1){

1622

perror("ioctl SIOCGIFFLAGS");

1623

} else if(network.ifr_flags & IFF_UP) {

1624

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

1625

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

1626

if(ret == -1){

1627

perror("ioctl SIOCSIFFLAGS");

1628

}

1629

}

1630

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

1631

if(ret == -1){

1632

perror("close");

1633

}

1634

/* Lower privileges permanently */

1635

errno = 0;

1636

ret = setuid(uid);

1637

if(ret == -1){

1638

perror("setuid");

1639

}

1640

}

1641

}

1642

1643

/* Removes the temp directory used by GPGME */

1644

if(tempdir_created){

1645

DIR *d;

1646

struct dirent *direntry;

1647

d = opendir(tempdir);

1648

if(d == NULL){

1649

if(errno != ENOENT){

1650

perror("opendir");

1651

}

1652

} else {

1653

while(true){

1654

direntry = readdir(d);

1655

if(direntry == NULL){

1656

break;

1657

}

1658

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

1659

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

1660

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

1661

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

1662

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

1663

continue;

1664

}

1665

char *fullname = NULL;

1666

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

1667

direntry->d_name);

1668

if(ret < 0){

1669

perror("asprintf");

1670

continue;

1671

}

1672

ret = remove(fullname);

1673

if(ret == -1){

1674

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

1675

strerror(errno));

1676

}

1677

free(fullname);

1678

}

1679

closedir(d);

1680

}

1681

ret = rmdir(tempdir);

1682

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

1683

perror("rmdir");

2673

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

2674

has seen */

2675

if(mc.current_server != NULL){

2676

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

2677

while(mc.current_server != NULL){

2678

server *next = mc.current_server->next;

2679

#ifdef __GNUC__

2680

#pragma GCC diagnostic push

2681

#pragma GCC diagnostic ignored "-Wcast-qual"

2682

#endif

2683

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

2684

#ifdef __GNUC__

2685

#pragma GCC diagnostic pop

2686

#endif

2687

free(mc.current_server);

2688

mc.current_server = next;

2689

}

2690

}

2691

2692

/* Re-raise privileges */

2693

{

2694

ret_errno = raise_privileges();

2695

if(ret_errno != 0){

2696

errno = ret_errno;

2697

perror_plus("Failed to raise privileges");

2698

} else {

2699

2700

/* Run network hooks */

2701

run_network_hooks("stop", interfaces_hooks != NULL ?

2702

interfaces_hooks : "", delay);

2703

2704

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

2705

{

2706

char *interface = NULL;

2707

while((interface=argz_next(interfaces_to_take_down,

2708

interfaces_to_take_down_size,

2709

interface))){

2710

ret_errno = take_down_interface(interface);

2711

if(ret_errno != 0){

2712

errno = ret_errno;

2713

perror_plus("Failed to take down interface");

2714

}

2715

}

2716

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

2717

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

2718

" down\n");

2719

}

2720

}

2721

}

2722

2723

ret_errno = lower_privileges_permanently();

2724

if(ret_errno != 0){

2725

errno = ret_errno;

2726

perror_plus("Failed to lower privileges permanently");

2727

}

2728

}

2729

2730

free(interfaces_to_take_down);

2731

free(interfaces_hooks);

2732

2733

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

2734

if(tempdir != NULL){

2735

struct dirent **direntries = NULL;

2736

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

2737

O_NOFOLLOW));

2738

if(tempdir_fd == -1){

2739

perror_plus("open");

2740

} else {

2741

#ifdef __GLIBC__

2742

#if __GLIBC_PREREQ(2, 15)

2743

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

2744

notdotentries, alphasort);

2745

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

2746

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

2747

alphasort);

2748

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

2749

#else /* not __GLIBC__ */

2750

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

2751

alphasort);

2752

#endif /* not __GLIBC__ */

2753

if(numentries >= 0){

2754

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

2755

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

2756

if(ret == -1){

2757

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

2758

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

2759

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

2760

}

2761

free(direntries[i]);

2762

}

2763

2764

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

2765

free(direntries);

2766

if(numentries == -1){

2767

perror_plus("scandir");

2768

}

2769

ret = rmdir(tempdir);

2770

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

2771

perror_plus("rmdir");

2772

}

2773

}

2774

TEMP_FAILURE_RETRY(close(tempdir_fd));

1684

2775

}

1685

2776

}

1686

2777

1691

2782

&old_sigterm_action,

1692

2783

NULL));

1693

2784

if(ret == -1){

1694

perror("sigaction");

2785

perror_plus("sigaction");

1695

2786

}

1696

2787

do {

1697

2788

ret = raise(signal_received);

1698

2789

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

1699

2790

if(ret != 0){

1700

perror("raise");

2791

perror_plus("raise");

1701

2792

abort();

1702

2793

}

1703

2794

TEMP_FAILURE_RETRY(pause());