/mandos/trunk : revision 24.1.186

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

26

* along with this program. If not, see

27

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

28

*

29

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

29

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

30

*/

31

32

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

41

42

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

43

stdout, ferror(), remove() */

44

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

44

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

45

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

46

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

47

strtof(), abort() */

53

sockaddr_in6, PF_INET6,

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

56

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

56

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

57

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

58

inet_pton(), connect() */

59

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

61

*/

62

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

63

strtoimax() */

64

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

64

65

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

65

66

program_invocation_short_name */

66

67

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

72

73

*/

73

74

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

74

75

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

75

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

76

setgid(), pause() */

76

77

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

77

78

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

78

79

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

84

85

raise() */

85

86

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

86

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

87

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

88

WEXITSTATUS(), WTERMSIG() */

89

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

90

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

91

argz_delete(), argz_append(),

92

argz_stringify(), argz_add(),

93

argz_count() */

94

88

95

89

#ifdef __linux__

96

90

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

114

108

init_gnutls_session(),

115

109

GNUTLS_* */

116

110

#include <gnutls/openpgp.h>

117

/* gnutls_certificate_set_openpgp_key_file(),

118

GNUTLS_OPENPGP_FMT_BASE64 */

111

/* gnutls_certificate_set_openpgp_key_file(),

112

GNUTLS_OPENPGP_FMT_BASE64 */

119

113

120

114

/* GPGME */

121

115

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

129

123

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

130

124

#define SECKEY "seckey.txt"

131

125

#define PUBKEY "pubkey.txt"

132

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

133

126

134

127

bool debug = false;

135

128

static const char mandos_protocol_version[] = "1";

136

129

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

137

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

130

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

138

131

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

139

132

char *connect_to = NULL;

140

const char *hookdir = HOOKDIR;

141

uid_t uid = 65534;

142

gid_t gid = 65534;

143

133

144

134

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

145

135

typedef struct server{

146

136

const char *ip;

147

in_port_t port;

137

uint16_t port;

148

138

AvahiIfIndex if_index;

149

139

int af;

150

140

struct timespec last_seen;

154

144

155

145

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

156

146

typedef struct {

147

AvahiSimplePoll *simple_poll;

157

148

AvahiServer *server;

158

149

gnutls_certificate_credentials_t cred;

159

150

unsigned int dh_bits;

161

152

const char *priority;

162

153

gpgme_ctx_t ctx;

163

154

server *current_server;

164

char *interfaces;

165

size_t interfaces_size;

166

155

} mandos_context;

167

156

168

/* global so signal handler can reach it*/

169

AvahiSimplePoll *simple_poll;

157

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

158

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

159

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

170

162

171

163

sig_atomic_t quit_now = 0;

172

164

int signal_received = 0;

173

165

174

166

/* Function to use when printing errors */

175

167

void perror_plus(const char *print_text){

176

int e = errno;

177

168

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

178

169

program_invocation_short_name);

179

errno = e;

180

170

perror(print_text);

181

171

}

182

172

183

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

184

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

185

va_list ap;

186

va_start (ap, format);

187

188

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

189

program_invocation_short_name));

190

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

191

}

192

193

173

/*

194

174

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

195

175

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

196

176

* "buffer_length" is how much is already used.

197

177

*/

198

178

size_t incbuffer(char **buffer, size_t buffer_length,

199

size_t buffer_capacity){

179

size_t buffer_capacity){

200

180

if(buffer_length + BUFFER_SIZE > buffer_capacity){

201

181

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

202

182

if(buffer == NULL){

208

188

}

209

189

210

190

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

211

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

212

int af, server **current_server){

191

int add_server(const char *ip, uint16_t port,

192

AvahiIfIndex if_index,

193

int af){

213

194

int ret;

214

195

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

215

196

if(new_server == NULL){

216

197

perror_plus("malloc");

217

return false;

198

return -1;

218

199

}

219

200

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

220

.port = port,

221

.if_index = if_index,

222

.af = af };

201

.port = port,

202

.if_index = if_index,

203

.af = af };

223

204

if(new_server->ip == NULL){

224

205

perror_plus("strdup");

225

return false;

206

return -1;

226

207

}

227

208

/* Special case of first server */

228

if(*current_server == NULL){

209

if (mc.current_server == NULL){

229

210

new_server->next = new_server;

230

211

new_server->prev = new_server;

231

*current_server = new_server;

212

mc.current_server = new_server;

232

213

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

233

214

} else {

234

new_server->next = *current_server;

235

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

215

new_server->next = mc.current_server;

216

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

236

217

new_server->prev->next = new_server;

237

(*current_server)->prev = new_server;

218

mc.current_server->prev = new_server;

238

219

}

239

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

220

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

240

221

if(ret == -1){

241

222

perror_plus("clock_gettime");

242

return false;

223

return -1;

243

224

}

244

return true;

225

return 0;

245

226

}

246

227

247

228

/*

248

229

* Initialize GPGME.

249

230

*/

250

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

251

const char *tempdir, mandos_context *mc){

231

static bool init_gpgme(const char *seckey,

232

const char *pubkey, const char *tempdir){

252

233

gpgme_error_t rc;

253

234

gpgme_engine_info_t engine_info;

254

235

236

255

237

/*

256

238

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

257

239

*/

268

250

269

251

rc = gpgme_data_new_from_fd(&pgp_data, fd);

270

252

if(rc != GPG_ERR_NO_ERROR){

271

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

272

gpgme_strsource(rc), gpgme_strerror(rc));

253

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

254

gpgme_strsource(rc), gpgme_strerror(rc));

273

255

return false;

274

256

}

275

257

276

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

258

rc = gpgme_op_import(mc.ctx, pgp_data);

277

259

if(rc != GPG_ERR_NO_ERROR){

278

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

279

gpgme_strsource(rc), gpgme_strerror(rc));

260

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

261

gpgme_strsource(rc), gpgme_strerror(rc));

280

262

return false;

281

263

}

282

264

289

271

}

290

272

291

273

if(debug){

292

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

274

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

293

275

}

294

276

295

277

/* Init GPGME */

296

278

gpgme_check_version(NULL);

297

279

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

298

280

if(rc != GPG_ERR_NO_ERROR){

299

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

300

gpgme_strsource(rc), gpgme_strerror(rc));

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

301

283

return false;

302

284

}

303

285

304

286

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

305

287

rc = gpgme_get_engine_info(&engine_info);

306

288

if(rc != GPG_ERR_NO_ERROR){

307

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

308

gpgme_strsource(rc), gpgme_strerror(rc));

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

309

291

return false;

310

292

}

311

293

while(engine_info != NULL){

317

299

engine_info = engine_info->next;

318

300

}

319

301

if(engine_info == NULL){

320

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

321

tempdir);

302

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

322

303

return false;

323

304

}

324

305

325

306

/* Create new GPGME "context" */

326

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

307

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

327

308

if(rc != GPG_ERR_NO_ERROR){

328

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

329

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

330

gpgme_strerror(rc));

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

331

311

return false;

332

312

}

333

313

344

324

*/

345

325

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

326

size_t crypto_size,

347

char **plaintext,

348

mandos_context *mc){

327

char **plaintext){

349

328

gpgme_data_t dh_crypto, dh_plain;

350

329

gpgme_error_t rc;

351

330

ssize_t ret;

353

332

ssize_t plaintext_length = 0;

354

333

355

334

if(debug){

356

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

335

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

357

336

}

358

337

359

338

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

360

339

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

361

340

0);

362

341

if(rc != GPG_ERR_NO_ERROR){

363

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

364

gpgme_strsource(rc), gpgme_strerror(rc));

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

365

344

return -1;

366

345

}

367

346

368

347

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

369

348

rc = gpgme_data_new(&dh_plain);

370

349

if(rc != GPG_ERR_NO_ERROR){

371

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

372

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

373

gpgme_strsource(rc), gpgme_strerror(rc));

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

374

352

gpgme_data_release(dh_crypto);

375

353

return -1;

376

354

}

377

355

378

356

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

379

357

data buffer */

380

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

358

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

381

359

if(rc != GPG_ERR_NO_ERROR){

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

384

362

plaintext_length = -1;

385

363

if(debug){

386

364

gpgme_decrypt_result_t result;

387

result = gpgme_op_decrypt_result(mc->ctx);

365

result = gpgme_op_decrypt_result(mc.ctx);

388

366

if(result == NULL){

389

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

367

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

390

368

} else {

391

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

392

result->unsupported_algorithm);

393

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

394

result->wrong_key_usage);

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

395

373

if(result->file_name != NULL){

396

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

374

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

397

375

}

398

376

gpgme_recipient_t recipient;

399

377

recipient = result->recipients;

400

378

while(recipient != NULL){

401

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

402

gpgme_pubkey_algo_name

403

(recipient->pubkey_algo));

404

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

405

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

408

385

recipient = recipient->next;

409

386

}

410

387

}

413

390

}

414

391

415

392

if(debug){

416

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

393

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

417

394

}

418

395

419

396

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

426

403

*plaintext = NULL;

427

404

while(true){

428

405

plaintext_capacity = incbuffer(plaintext,

429

(size_t)plaintext_length,

430

plaintext_capacity);

406

(size_t)plaintext_length,

407

plaintext_capacity);

431

408

if(plaintext_capacity == 0){

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

435

412

}

436

413

437

414

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

450

427

}

451

428

452

429

if(debug){

453

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

430

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

454

431

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

455

432

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

456

433

}

468

445

}

469

446

470

447

static const char * safer_gnutls_strerror(int value){

471

const char *ret = gnutls_strerror(value);

448

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

449

-Wunreachable-code */

472

450

if(ret == NULL)

473

451

ret = "(unknown)";

474

452

return ret;

477

455

/* GnuTLS log function callback */

478

456

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

479

457

const char* string){

480

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

458

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

481

459

}

482

460

483

461

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename,

485

mandos_context *mc){

462

const char *seckeyfilename){

486

463

int ret;

487

464

488

465

if(debug){

489

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

466

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

490

467

}

491

468

492

469

ret = gnutls_global_init();

493

470

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

496

473

return -1;

497

474

}

498

475

505

482

}

506

483

507

484

/* OpenPGP credentials */

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

509

486

if(ret != GNUTLS_E_SUCCESS){

510

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

511

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

512

489

gnutls_global_deinit();

513

490

return -1;

514

491

}

515

492

516

493

if(debug){

517

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

518

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

519

pubkeyfilename,

520

seckeyfilename);

494

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

495

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

496

seckeyfilename);

521

497

}

522

498

523

499

ret = gnutls_certificate_set_openpgp_key_file

524

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

525

501

GNUTLS_OPENPGP_FMT_BASE64);

526

502

if(ret != GNUTLS_E_SUCCESS){

527

fprintf_plus(stderr,

528

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

529

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

530

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

531

safer_gnutls_strerror(ret));

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

532

508

goto globalfail;

533

509

}

534

510

535

511

/* GnuTLS server initialization */

536

ret = gnutls_dh_params_init(&mc->dh_params);

512

ret = gnutls_dh_params_init(&mc.dh_params);

537

513

if(ret != GNUTLS_E_SUCCESS){

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

514

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

515

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

541

516

goto globalfail;

542

517

}

543

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

518

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

544

519

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

520

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

521

safer_gnutls_strerror(ret));

547

522

goto globalfail;

548

523

}

549

524

550

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

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

551

526

552

527

return 0;

553

528

554

529

globalfail:

555

530

556

gnutls_certificate_free_credentials(mc->cred);

531

gnutls_certificate_free_credentials(mc.cred);

557

532

gnutls_global_deinit();

558

gnutls_dh_params_deinit(mc->dh_params);

533

gnutls_dh_params_deinit(mc.dh_params);

559

534

return -1;

560

535

}

561

536

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

564

538

int ret;

565

539

/* GnuTLS session creation */

566

540

do {

570

544

}

571

545

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

572

546

if(ret != GNUTLS_E_SUCCESS){

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

547

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

548

safer_gnutls_strerror(ret));

576

549

}

577

550

578

551

{

579

552

const char *err;

580

553

do {

581

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

554

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

582

555

if(quit_now){

583

556

gnutls_deinit(*session);

584

557

return -1;

585

558

}

586

559

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

587

560

if(ret != GNUTLS_E_SUCCESS){

588

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

589

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

590

safer_gnutls_strerror(ret));

561

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

562

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

563

safer_gnutls_strerror(ret));

591

564

gnutls_deinit(*session);

592

565

return -1;

593

566

}

595

568

596

569

do {

597

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

598

mc->cred);

571

mc.cred);

599

572

if(quit_now){

600

573

gnutls_deinit(*session);

601

574

return -1;

602

575

}

603

576

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

604

577

if(ret != GNUTLS_E_SUCCESS){

605

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

606

safer_gnutls_strerror(ret));

578

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

579

safer_gnutls_strerror(ret));

607

580

gnutls_deinit(*session);

608

581

return -1;

609

582

}

611

584

/* ignore client certificate if any. */

612

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

586

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

615

588

616

589

return 0;

617

590

}

621

594

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

622

595

623

596

/* Called when a Mandos server is found */

624

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

597

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

625

598

AvahiIfIndex if_index,

626

int af, mandos_context *mc){

599

int af){

627

600

int ret, tcp_sd = -1;

628

601

ssize_t sret;

629

602

union {

654

627

pf = PF_INET;

655

628

break;

656

629

default:

657

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

630

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

658

631

errno = EINVAL;

659

632

return -1;

660

633

}

661

634

662

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

663

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

664

bool match = false;

665

{

666

char *interface = NULL;

667

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

668

interface))){

669

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

670

match = true;

671

break;

672

}

673

}

674

}

675

if(not match){

676

if(debug){

677

char interface[IF_NAMESIZE];

678

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

679

perror_plus("if_indextoname");

680

} else {

681

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

682

" \"%s\"\n",

683

if_indextoname((unsigned int)if_index,

684

interface));

685

}

686

}

687

return -1;

688

}

689

}

690

691

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

692

636

if(ret != 0){

693

637

return -1;

694

638

}

695

639

696

640

if(debug){

697

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

698

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

641

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

642

"\n", ip, port);

699

643

}

700

644

701

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

727

671

}

728

672

if(ret == 0){

729

673

int e = errno;

730

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

674

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

731

675

errno = e;

732

676

goto mandos_end;

733

677

}

734

678

if(af == AF_INET6){

735

to.in6.sin6_port = htons(port);

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

736

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

737

684

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

738

-Wunreachable-code*/

685

-Wunreachable-code*/

739

686

if(if_index == AVAHI_IF_UNSPEC){

740

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

741

" incomplete without a network interface\n");

687

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

688

" without a network interface\n");

742

689

errno = EINVAL;

743

690

goto mandos_end;

744

691

}

762

709

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

763

710

perror_plus("if_indextoname");

764

711

} else {

765

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

766

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

712

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

713

ip, interface, port);

767

714

}

768

715

} else {

769

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

770

ip, (uintmax_t)port);

716

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

717

port);

771

718

}

772

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

773

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

783

730

perror_plus("inet_ntop");

784

731

} else {

785

732

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

786

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

733

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

787

734

}

788

735

}

789

736

}

817

764

while(true){

818

765

size_t out_size = strlen(out);

819

766

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

820

out_size - written));

767

out_size - written));

821

768

if(ret == -1){

822

769

int e = errno;

823

770

perror_plus("write");

843

790

}

844

791

845

792

if(debug){

846

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

793

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

847

794

}

848

795

849

796

if(quit_now){

851

798

goto mandos_end;

852

799

}

853

800

854

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

855

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

856

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

857

gnutls_transport_set_ptr(session,

858

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

859

803

860

804

if(quit_now){

861

805

errno = EINTR;

872

816

873

817

if(ret != GNUTLS_E_SUCCESS){

874

818

if(debug){

875

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

819

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

876

820

gnutls_perror(ret);

877

821

}

878

822

errno = EPROTO;

882

826

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

883

827

884

828

if(debug){

885

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

886

" %s\n", ip);

829

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

830

ip);

887

831

}

888

832

889

833

while(true){

894

838

}

895

839

896

840

buffer_capacity = incbuffer(&buffer, buffer_length,

897

buffer_capacity);

841

buffer_capacity);

898

842

if(buffer_capacity == 0){

899

843

int e = errno;

900

844

perror_plus("incbuffer");

927

871

}

928

872

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

929

873

if(ret < 0){

930

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

931

"***\n");

874

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

932

875

gnutls_perror(ret);

933

876

errno = EPROTO;

934

877

goto mandos_end;

935

878

}

936

879

break;

937

880

default:

938

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

939

" encrypted session with Mandos server\n");

881

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

882

" encrypted session with Mandos server\n");

940

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

941

884

errno = EIO;

942

885

goto mandos_end;

947

890

}

948

891

949

892

if(debug){

950

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

893

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

951

894

}

952

895

953

896

if(quit_now){

965

908

966

909

if(buffer_length > 0){

967

910

ssize_t decrypted_buffer_size;

968

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

969

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

970

914

if(decrypted_buffer_size >= 0){

971

915

972

916

written = 0;

982

926

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

983

927

int e = errno;

984

928

if(debug){

985

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

986

strerror(errno));

929

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

930

strerror(errno));

987

931

}

988

932

errno = e;

989

933

goto mandos_end;

1033

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1034

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1035

979

flags,

1036

void* mc){

1037

if(r == NULL){

1038

return;

1039

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1040

982

1041

983

/* Called whenever a service has been resolved successfully or

1042

984

timed out */

1048

990

switch(event){

1049

991

default:

1050

992

case AVAHI_RESOLVER_FAILURE:

1051

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

1052

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

1053

domain,

1054

avahi_strerror(avahi_server_errno

1055

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

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1056

996

break;

1057

997

1058

998

case AVAHI_RESOLVER_FOUND:

1060

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1061

1001

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

1062

1002

if(debug){

1063

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

1064

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

1065

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

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1066

1006

}

1067

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

1068

interface,

1069

avahi_proto_to_af(proto),

1070

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1071

1009

if(ret == 0){

1072

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1073

1011

} else {

1074

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

1075

avahi_proto_to_af(proto),

1076

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

1077

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

1078

" list\n", name);

1079

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1080

1014

}

1081

1015

}

1082

1016

}

1092

1026

const char *domain,

1093

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1094

1028

flags,

1095

void* mc){

1096

if(b == NULL){

1097

return;

1098

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1099

1031

1100

1032

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

1101

1033

is removed from the LAN */

1108

1040

default:

1109

1041

case AVAHI_BROWSER_FAILURE:

1110

1042

1111

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

1112

avahi_strerror(avahi_server_errno

1113

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

1114

avahi_simple_poll_quit(simple_poll);

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1115

1046

return;

1116

1047

1117

1048

case AVAHI_BROWSER_NEW:

1120

1051

the callback function is called the Avahi server will free the

1121

1052

resolver for us. */

1122

1053

1123

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

1124

interface, protocol, name, type,

1125

domain, protocol, 0,

1126

resolve_callback, mc) == NULL)

1127

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

1128

" %s\n", name,

1129

avahi_strerror(avahi_server_errno

1130

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

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

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

1058

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

1131

1059

break;

1132

1060

1133

1061

case AVAHI_BROWSER_REMOVE:

1136

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1137

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1138

1066

if(debug){

1139

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

1140

" searching...\n");

1067

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

1141

1068

}

1142

1069

break;

1143

1070

}

1152

1079

signal_received = sig;

1153

1080

int old_errno = errno;

1154

1081

/* set main loop to exit */

1155

if(simple_poll != NULL){

1156

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1157

1084

}

1158

1085

errno = old_errno;

1159

1086

}

1160

1087

1161

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

1162

int ret;

1163

error_t ret_errno;

1164

1165

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

1166

if(s < 0){

1167

ret_errno = errno;

1168

perror_plus("socket");

1169

errno = ret_errno;

1170

return false;

1171

}

1172

strcpy(ifr->ifr_name, ifname);

1173

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1174

if(ret == -1){

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

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

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1175

1144

if(debug){

1176

ret_errno = errno;

1177

perror_plus("ioctl SIOCGIFFLAGS");

1178

errno = ret_errno;

1145

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

1146

flagstring, if_entry->d_name);

1179

1147

}

1180

return false;

1148

free(flagstring);

1149

return 0;

1181

1150

}

1182

return true;

1183

}

1184

1185

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

1186

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1187

1153

/* Reject the loopback device */

1188

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1189

1155

if(debug){

1190

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

1191

ifname);

1156

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

1157

if_entry->d_name);

1192

1158

}

1193

return false;

1159

return 0;

1194

1160

}

1195

1161

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

1196

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

1162

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

1197

1163

if(debug){

1198

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

1199

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

1164

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

1165

if_entry->d_name);

1200

1166

}

1201

return true;

1167

return 1;

1202

1168

}

1203

1169

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

1204

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

1170

if(not (flags & IFF_BROADCAST)){

1205

1171

if(debug){

1206

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1207

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

1172

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

1173

if_entry->d_name);

1208

1174

}

1209

return false;

1175

return 0;

1210

1176

}

1211

1177

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

1212

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1213

1179

if(debug){

1214

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

1215

ifname);

1180

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

1181

if_entry->d_name);

1216

1182

}

1217

return false;

1183

return 0;

1218

1184

}

1219

1220

1185

/* Accept this device */

1221

1186

if(debug){

1222

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

1223

}

1224

return true;

1225

}

1226

1227

/*

1228

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

1229

* corresponds to an acceptable network device.

1230

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

1231

*/

1232

int good_interface(const struct dirent *if_entry){

1233

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

1234

return 0;

1235

}

1236

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return 0;

1244

}

1245

1246

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

1247

return 0;

1187

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

1188

if_entry->d_name);

1248

1189

}

1249

1190

return 1;

1250

1191

}

1251

1192

1252

/*

1253

* This function determines if a network interface is up.

1254

*/

1255

bool interface_is_up(const char *interface){

1256

struct ifreq ifr;

1257

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

1258

if(debug){

1259

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

1260

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

1261

}

1262

return false;

1263

}

1264

1265

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

1266

}

1267

1268

/*

1269

* This function determines if a network interface is running

1270

*/

1271

bool interface_is_running(const char *interface){

1272

struct ifreq ifr;

1273

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

1274

if(debug){

1275

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

1276

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

1277

}

1278

return false;

1279

}

1280

1281

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

1282

}

1283

1284

1193

int notdotentries(const struct dirent *direntry){

1285

1194

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

1286

1195

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

1292

1201

return 1;

1293

1202

}

1294

1203

1295

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

1296

int runnable_hook(const struct dirent *direntry){

1297

int ret;

1298

size_t sret;

1299

struct stat st;

1300

1301

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

1302

/* Empty name? */

1303

return 0;

1304

}

1305

1306

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

1307

"abcdefghijklmnopqrstuvwxyz"

1308

"0123456789"

1309

"_-");

1310

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

1311

/* Contains non-allowed characters */

1312

if(debug){

1313

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

1314

direntry->d_name);

1315

}

1316

return 0;

1317

}

1318

1319

char *fullname = NULL;

1320

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

1321

if(ret < 0){

1322

perror_plus("asprintf");

1323

return 0;

1324

}

1325

1326

ret = stat(fullname, &st);

1327

if(ret == -1){

1328

if(debug){

1329

perror_plus("Could not stat hook");

1330

}

1331

return 0;

1332

}

1333

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

1334

/* Not a regular file */

1335

if(debug){

1336

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

1337

direntry->d_name);

1338

}

1339

return 0;

1340

}

1341

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

1342

/* Not executable */

1343

if(debug){

1344

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

1345

direntry->d_name);

1346

}

1347

return 0;

1348

}

1349

if(debug){

1350

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

1351

direntry->d_name);

1352

}

1353

return 1;

1354

}

1355

1356

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1357

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1358

1205

int ret;

1359

1206

struct timespec now;

1360

1207

struct timespec waited_time;

1361

1208

intmax_t block_time;

1362

1209

1363

1210

while(true){

1364

if(mc->current_server == NULL){

1211

if(mc.current_server == NULL){

1365

1212

if (debug){

1366

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

1367

" No timeout!\n");

1213

fprintf(stderr,

1214

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

1368

1215

}

1369

1216

ret = avahi_simple_poll_iterate(s, -1);

1370

1217

} else {

1371

1218

if (debug){

1372

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

1373

" it, or wait\n");

1219

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

1220

" or wait\n");

1374

1221

}

1375

1222

/* the current time */

1376

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1381

1228

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

1382

1229

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

1383

1230

waited_time.tv_sec = (now.tv_sec

1384

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

1231

- mc.current_server->last_seen.tv_sec);

1385

1232

waited_time.tv_nsec = (now.tv_nsec

1386

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

1233

- mc.current_server->last_seen.tv_nsec);

1387

1234

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

1388

1235

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

1389

1236

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

1392

1239

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

1393

1240

1394

1241

if (debug){

1395

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

1396

block_time);

1242

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

1397

1243

}

1398

1244

1399

1245

if(block_time <= 0){

1400

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

1401

mc->current_server->port,

1402

mc->current_server->if_index,

1403

mc->current_server->af, mc);

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1404

1250

if(ret == 0){

1405

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

1406

1252

return 0;

1407

1253

}

1408

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1409

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

1410

1256

if(ret == -1){

1411

1257

perror_plus("clock_gettime");

1412

1258

return -1;

1413

1259

}

1414

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

1260

mc.current_server = mc.current_server->next;

1415

1261

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

1416

1262

servers, but don't block */

1417

1263

}

1419

1265

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

1420

1266

}

1421

1267

if(ret != 0){

1422

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

1268

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

1423

1269

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

1424

1270

}

1425

1271

}

1426

1272

}

1427

1273

}

1428

1274

1429

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

1430

error_t raise_privileges(void){

1431

error_t old_errno = errno;

1432

error_t ret_errno = 0;

1433

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

1434

ret_errno = errno;

1435

perror_plus("seteuid");

1436

}

1437

errno = old_errno;

1438

return ret_errno;

1439

}

1440

1441

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

1442

error_t raise_privileges_permanently(void){

1443

error_t old_errno = errno;

1444

error_t ret_errno = raise_privileges();

1445

if(ret_errno != 0){

1446

errno = old_errno;

1447

return ret_errno;

1448

}

1449

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

1450

ret_errno = errno;

1451

perror_plus("seteuid");

1452

}

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

1457

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

1458

error_t lower_privileges(void){

1459

error_t old_errno = errno;

1460

error_t ret_errno = 0;

1461

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

1462

ret_errno = errno;

1463

perror_plus("seteuid");

1464

}

1465

errno = old_errno;

1466

return ret_errno;

1467

}

1468

1469

/* Lower privileges permanently */

1470

error_t lower_privileges_permanently(void){

1471

error_t old_errno = errno;

1472

error_t ret_errno = 0;

1473

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

1474

ret_errno = errno;

1475

perror_plus("setuid");

1476

}

1477

errno = old_errno;

1478

return ret_errno;

1479

}

1480

1481

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

1482

const float delay){

1483

struct dirent **direntries;

1484

struct dirent *direntry;

1485

int ret;

1486

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

1487

alphasort);

1488

if(numhooks == -1){

1489

if(errno == ENOENT){

1490

if(debug){

1491

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

1492

" found\n", hookdir);

1493

}

1494

} else {

1495

perror_plus("scandir");

1496

}

1497

} else {

1498

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

1499

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

1500

direntry = direntries[i];

1501

char *fullname = NULL;

1502

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

1503

if(ret < 0){

1504

perror_plus("asprintf");

1505

continue;

1506

}

1507

if(debug){

1508

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

1509

direntry->d_name);

1510

}

1511

pid_t hook_pid = fork();

1512

if(hook_pid == 0){

1513

/* Child */

1514

/* Raise privileges */

1515

raise_privileges_permanently();

1516

/* Set group */

1517

errno = 0;

1518

ret = setgid(0);

1519

if(ret == -1){

1520

perror_plus("setgid");

1521

}

1522

/* Reset supplementary groups */

1523

errno = 0;

1524

ret = setgroups(0, NULL);

1525

if(ret == -1){

1526

perror_plus("setgroups");

1527

}

1528

dup2(devnull, STDIN_FILENO);

1529

close(devnull);

1530

dup2(STDERR_FILENO, STDOUT_FILENO);

1531

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

1532

if(ret == -1){

1533

perror_plus("setenv");

1534

_exit(EX_OSERR);

1535

}

1536

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

1537

if(ret == -1){

1538

perror_plus("setenv");

1539

_exit(EX_OSERR);

1540

}

1541

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

1542

if(ret == -1){

1543

perror_plus("setenv");

1544

_exit(EX_OSERR);

1545

}

1546

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

1547

if(ret == -1){

1548

perror_plus("setenv");

1549

_exit(EX_OSERR);

1550

}

1551

char *delaystring;

1552

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

1553

if(ret == -1){

1554

perror_plus("asprintf");

1555

_exit(EX_OSERR);

1556

}

1557

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

1558

if(ret == -1){

1559

free(delaystring);

1560

perror_plus("setenv");

1561

_exit(EX_OSERR);

1562

}

1563

free(delaystring);

1564

if(connect_to != NULL){

1565

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

1566

if(ret == -1){

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1570

}

1571

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

1572

perror_plus("execl");

1573

_exit(EXIT_FAILURE);

1574

}

1575

} else {

1576

int status;

1577

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

1578

perror_plus("waitpid");

1579

free(fullname);

1580

continue;

1581

}

1582

if(WIFEXITED(status)){

1583

if(WEXITSTATUS(status) != 0){

1584

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

1585

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

1586

WEXITSTATUS(status));

1587

free(fullname);

1588

continue;

1589

}

1590

} else if(WIFSIGNALED(status)){

1591

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

1592

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

1593

WTERMSIG(status));

1594

free(fullname);

1595

continue;

1596

} else {

1597

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

1598

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

1599

free(fullname);

1600

continue;

1601

}

1602

}

1603

free(fullname);

1604

if(debug){

1605

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

1606

direntry->d_name);

1607

}

1608

}

1609

close(devnull);

1610

}

1611

return true;

1612

}

1613

1614

error_t bring_up_interface(const char *const interface,

1615

const float delay){

1616

int sd = -1;

1617

error_t old_errno = errno;

1618

error_t ret_errno = 0;

1619

int ret, ret_setflags;

1620

struct ifreq network;

1621

unsigned int if_index = if_nametoindex(interface);

1622

if(if_index == 0){

1623

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

1624

errno = old_errno;

1625

return ENXIO;

1626

}

1627

1628

if(quit_now){

1629

errno = old_errno;

1630

return EINTR;

1631

}

1632

1633

if(not interface_is_up(interface)){

1634

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

1635

ret_errno = errno;

1636

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

1637

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

1638

return ret_errno;

1639

}

1640

network.ifr_flags |= IFF_UP;

1641

1642

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1643

if(sd < 0){

1644

ret_errno = errno;

1645

perror_plus("socket");

1646

errno = old_errno;

1647

return ret_errno;

1648

}

1649

1650

if(quit_now){

1651

close(sd);

1652

errno = old_errno;

1653

return EINTR;

1654

}

1655

1656

if(debug){

1657

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

1658

interface);

1659

}

1660

1661

/* Raise priviliges */

1662

raise_privileges();

1663

1664

#ifdef __linux__

1665

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1666

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

1667

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

1668

bool restore_loglevel = true;

1669

if(ret_linux == -1){

1670

restore_loglevel = false;

1671

perror_plus("klogctl");

1672

}

1673

#endif /* __linux__ */

1674

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

1675

ret_errno = errno;

1676

#ifdef __linux__

1677

if(restore_loglevel){

1678

ret_linux = klogctl(7, NULL, 0);

1679

if(ret_linux == -1){

1680

perror_plus("klogctl");

1681

}

1682

}

1683

#endif /* __linux__ */

1684

1685

/* Lower privileges */

1686

lower_privileges();

1687

1688

/* Close the socket */

1689

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

1690

if(ret == -1){

1691

perror_plus("close");

1692

}

1693

1694

if(ret_setflags == -1){

1695

errno = ret_errno;

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1697

errno = old_errno;

1698

return ret_errno;

1699

}

1700

} else if(debug){

1701

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

1702

interface);

1703

}

1704

1705

/* Sleep checking until interface is running.

1706

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

1707

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

1708

if(interface_is_running(interface)){

1709

break;

1710

}

1711

struct timespec sleeptime = { .tv_nsec = 250000000 };

1712

ret = nanosleep(&sleeptime, NULL);

1713

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

1714

perror_plus("nanosleep");

1715

}

1716

}

1717

1718

errno = old_errno;

1719

return 0;

1720

}

1721

1722

error_t take_down_interface(const char *const interface){

1723

int sd = -1;

1724

error_t old_errno = errno;

1725

error_t ret_errno = 0;

1726

int ret, ret_setflags;

1727

struct ifreq network;

1728

unsigned int if_index = if_nametoindex(interface);

1729

if(if_index == 0){

1730

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

1731

errno = old_errno;

1732

return ENXIO;

1733

}

1734

if(interface_is_up(interface)){

1735

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

1736

ret_errno = errno;

1737

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

1738

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

1739

return ret_errno;

1740

}

1741

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

1742

1743

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1744

if(sd < 0){

1745

ret_errno = errno;

1746

perror_plus("socket");

1747

errno = old_errno;

1748

return ret_errno;

1749

}

1750

1751

if(debug){

1752

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

1753

interface);

1754

}

1755

1756

/* Raise priviliges */

1757

raise_privileges();

1758

1759

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

1760

ret_errno = errno;

1761

1762

/* Lower privileges */

1763

lower_privileges();

1764

1765

/* Close the socket */

1766

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

1767

if(ret == -1){

1768

perror_plus("close");

1769

}

1770

1771

if(ret_setflags == -1){

1772

errno = ret_errno;

1773

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1774

errno = old_errno;

1775

return ret_errno;

1776

}

1777

} else if(debug){

1778

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

1779

interface);

1780

}

1781

1782

errno = old_errno;

1783

return 0;

1784

}

1785

1786

1275

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

1787

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

1788

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

1789

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

1790

.interfaces = NULL, .interfaces_size = 0 };

1791

1276

AvahiSServiceBrowser *sb = NULL;

1792

error_t ret_errno;

1277

int error;

1793

1278

int ret;

1794

1279

intmax_t tmpmax;

1795

1280

char *tmp;

1796

1281

int exitcode = EXIT_SUCCESS;

1797

char *interfaces_to_take_down = NULL;

1798

size_t interfaces_to_take_down_size = 0;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1799

1288

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

1800

1289

bool tempdir_created = false;

1801

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1802

1291

const char *seckey = PATHDIR "/" SECKEY;

1803

1292

const char *pubkey = PATHDIR "/" PUBKEY;

1804

char *interfaces_hooks = NULL;

1805

size_t interfaces_hooks_size = 0;

1806

1293

1807

1294

bool gnutls_initialized = false;

1808

1295

bool gpgme_initialized = false;

1870

1357

.group = 2 },

1871

1358

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

1872

1359

.arg = "SECONDS",

1873

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

1874

.group = 2 },

1875

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

1876

.arg = "DIR",

1877

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

1360

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

1878

1361

.group = 2 },

1879

1362

/*

1880

1363

* These reproduce what we would get without ARGP_NO_HELP

1899

1382

connect_to = arg;

1900

1383

break;

1901

1384

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

1902

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

1903

arg, (int)',');

1904

if(ret_errno != 0){

1905

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

1906

}

1385

interface = arg;

1907

1386

break;

1908

1387

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

1909

1388

seckey = arg;

1938

1417

argp_error(state, "Bad retry interval");

1939

1418

}

1940

1419

break;

1941

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

1942

hookdir = arg;

1943

break;

1944

1420

/*

1945

1421

* These reproduce what we would get without ARGP_NO_HELP

1946

1422

*/

1952

1428

argp_state_help(state, state->out_stream,

1953

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1954

1430

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

1955

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

1431

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

1956

1432

exit(argp_err_exit_status);

1957

1433

break;

1958

1434

default:

1985

1461

{

1986

1462

/* Work around Debian bug #633582:

1987

1463

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

1464

struct stat st;

1988

1465

1989

1466

/* Re-raise priviliges */

1990

if(raise_privileges() == 0){

1991

struct stat st;

1992

1993

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

1994

int seckey_fd = open(seckey, O_RDONLY);

1995

if(seckey_fd == -1){

1996

perror_plus("open");

1997

} else {

1998

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

1999

if(ret == -1){

2000

perror_plus("fstat");

2001

} else {

2002

if(S_ISREG(st.st_mode)

2003

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

2004

ret = fchown(seckey_fd, uid, gid);

2005

if(ret == -1){

2006

perror_plus("fchown");

2007

}

2008

}

2009

}

2010

TEMP_FAILURE_RETRY(close(seckey_fd));

2011

}

2012

}

2013

2014

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

2015

int pubkey_fd = open(pubkey, O_RDONLY);

2016

if(pubkey_fd == -1){

2017

perror_plus("open");

2018

} else {

2019

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

2020

if(ret == -1){

2021

perror_plus("fstat");

2022

} else {

2023

if(S_ISREG(st.st_mode)

2024

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

2025

ret = fchown(pubkey_fd, uid, gid);

2026

if(ret == -1){

2027

perror_plus("fchown");

2028

}

2029

}

2030

}

2031

TEMP_FAILURE_RETRY(close(pubkey_fd));

2032

}

2033

}

2034

2035

/* Lower privileges */

2036

lower_privileges();

2037

}

2038

}

2039

2040

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

2041

{

2042

char *interface = NULL;

2043

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

2044

interface))){

2045

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

2046

and if_nametoindex(interface) == 0){

2047

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

2048

fprintf_plus(stderr, "Not using nonexisting interface"

2049

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

2050

}

2051

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

2052

interface = NULL;

2053

}

2054

}

2055

}

2056

2057

/* Run network hooks */

2058

{

2059

if(mc.interfaces != NULL){

2060

interfaces_hooks = malloc(mc.interfaces_size);

2061

if(interfaces_hooks == NULL){

2062

perror_plus("malloc");

2063

goto end;

2064

}

2065

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

2066

interfaces_hooks_size = mc.interfaces_size;

2067

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2068

(int)',');

2069

}

2070

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2071

interfaces_hooks : "", delay)){

2072

goto end;

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

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

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

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

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

2073

1518

}

2074

1519

}

2075

1520

2076

1521

if(not debug){

2077

1522

avahi_set_log_function(empty_log);

2078

1523

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

2079

1549

2080

1550

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

2081

1551

from the signal handler */

2082

1552

/* Initialize the pseudo-RNG for Avahi */

2083

1553

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

2084

simple_poll = avahi_simple_poll_new();

2085

if(simple_poll == NULL){

2086

fprintf_plus(stderr,

2087

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

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

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

2088

1557

exitcode = EX_UNAVAILABLE;

2089

1558

goto end;

2090

1559

}

2152

1621

}

2153

1622

}

2154

1623

2155

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

2156

if(mc.interfaces == NULL){

2157

struct dirent **direntries;

2158

/* Look for any good interfaces */

2159

ret = scandir(sys_class_net, &direntries, good_interface,

2160

alphasort);

2161

if(ret >= 1){

2162

/* Add all found interfaces to interfaces list */

2163

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

2164

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

2165

direntries[i]->d_name);

2166

if(ret_errno != 0){

2167

perror_plus("argz_add");

2168

continue;

2169

}

2170

if(debug){

2171

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

2172

direntries[i]->d_name);

2173

}

2174

}

2175

free(direntries);

2176

} else {

2177

free(direntries);

2178

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

2179

exitcode = EXIT_FAILURE;

2180

goto end;

2181

}

2182

}

2183

2184

/* Bring up interfaces which are down */

2185

{

2186

char *interface = NULL;

2187

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

2188

interface))){

2189

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

2190

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

2191

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

2192

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

2193

interface);

2194

interface = NULL;

2195

while((interface = argz_next(mc.interfaces,

2196

mc.interfaces_size, interface))){

2197

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

2198

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

2199

interface);

2200

interface = NULL;

1624

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

2201

1709

}

2202

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

2203

1728

break;

2204

1729

}

2205

bool interface_was_up = interface_is_up(interface);

2206

ret = bring_up_interface(interface, delay);

2207

if(not interface_was_up){

2208

if(ret != 0){

2209

errno = ret;

2210

perror_plus("Failed to bring up interface");

2211

} else {

2212

ret_errno = argz_add(&interfaces_to_take_down,

2213

&interfaces_to_take_down_size,

2214

interface);

2215

}

2216

}

2217

}

2218

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

2219

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

2220

}

2221

}

2222

2223

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

2224

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

2225

if(debug){

2226

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

2227

mc.interfaces);

2228

}

2229

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

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

2230

1767

}

2231

1768

2232

1769

if(quit_now){

2233

1770

goto end;

2234

1771

}

2235

1772

2236

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

1773

ret = init_gnutls_global(pubkey, seckey);

2237

1774

if(ret == -1){

2238

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

1775

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

2239

1776

exitcode = EX_UNAVAILABLE;

2240

1777

goto end;

2241

1778

} else {

2256

1793

goto end;

2257

1794

}

2258

1795

2259

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

2260

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

1796

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

1797

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

2261

1798

exitcode = EX_UNAVAILABLE;

2262

1799

goto end;

2263

1800

} else {

2272

1809

/* Connect directly, do not use Zeroconf */

2273

1810

/* (Mainly meant for debugging) */

2274

1811

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

2275

2276

1812

if(address == NULL){

2277

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

1813

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

2278

1814

exitcode = EX_USAGE;

2279

1815

goto end;

2280

1816

}

2283

1819

goto end;

2284

1820

}

2285

1821

2286

in_port_t port;

1822

uint16_t port;

2287

1823

errno = 0;

2288

1824

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

2289

1825

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

2290

or tmpmax != (in_port_t)tmpmax){

2291

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2292

1828

exitcode = EX_USAGE;

2293

1829

goto end;

2294

1830

}

2295

1831

2296

1832

if(quit_now){

2297

1833

goto end;

2298

1834

}

2299

1835

2300

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

2301

1837

*address = '\0';

2302

1838

/* Colon in address indicates IPv6 */

2303

1839

int af;

2319

1855

}

2320

1856

2321

1857

while(not quit_now){

2322

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

2323

&mc);

1858

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

2324

1859

if(quit_now or ret == 0){

2325

1860

break;

2326

1861

}

2327

1862

if(debug){

2328

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

2329

(int)retry_interval);

1863

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

1864

(int)retry_interval);

2330

1865

}

2331

1866

sleep((int)retry_interval);

2332

1867

}

2334

1869

if (not quit_now){

2335

1870

exitcode = EXIT_SUCCESS;

2336

1871

}

2337

1872

2338

1873

goto end;

2339

1874

}

2340

1875

2352

1887

config.publish_domain = 0;

2353

1888

2354

1889

/* Allocate a new server */

2355

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2356

&config, NULL, NULL, &ret_errno);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2357

1893

2358

1894

/* Free the Avahi configuration data */

2359

1895

avahi_server_config_free(&config);

2361

1897

2362

1898

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

2363

1899

if(mc.server == NULL){

2364

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

2365

avahi_strerror(ret_errno));

1900

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

1901

avahi_strerror(error));

2366

1902

exitcode = EX_UNAVAILABLE;

2367

1903

goto end;

2368

1904

}

2374

1910

/* Create the Avahi service browser */

2375

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

2376

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2377

NULL, 0, browse_callback,

2378

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

2379

1914

if(sb == NULL){

2380

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

2381

avahi_strerror(avahi_server_errno(mc.server)));

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2382

1917

exitcode = EX_UNAVAILABLE;

2383

1918

goto end;

2384

1919

}

2390

1925

/* Run the main loop */

2391

1926

2392

1927

if(debug){

2393

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

1928

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

2394

1929

}

2395

1930

2396

ret = avahi_loop_with_timeout(simple_poll,

2397

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

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2398

1933

if(debug){

2399

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

2400

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

1934

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

1935

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

2401

1936

}

2402

1937

2403

1938

end:

2404

1939

2405

1940

if(debug){

2406

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

1941

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

2407

1942

}

2408

1943

2409

1944

/* Cleanup things */

2410

free(mc.interfaces);

2411

2412

1945

if(sb != NULL)

2413

1946

avahi_s_service_browser_free(sb);

2414

1947

2415

1948

if(mc.server != NULL)

2416

1949

avahi_server_free(mc.server);

2417

1950

2418

if(simple_poll != NULL)

2419

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2420

1953

2421

1954

if(gnutls_initialized){

2422

1955

gnutls_certificate_free_credentials(mc.cred);

2427

1960

if(gpgme_initialized){

2428

1961

gpgme_release(mc.ctx);

2429

1962

}

2430

1963

2431

1964

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

2432

1965

has seen */

2433

1966

if(mc.current_server != NULL){

2439

1972

}

2440

1973

}

2441

1974

2442

/* Re-raise priviliges */

2443

{

2444

raise_privileges();

2445

2446

/* Run network hooks */

2447

run_network_hooks("stop", interfaces_hooks != NULL ?

2448

interfaces_hooks : "", delay);

2449

2450

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

2451

{

2452

char *interface = NULL;

2453

while((interface=argz_next(interfaces_to_take_down,

2454

interfaces_to_take_down_size,

2455

interface))){

2456

ret_errno = take_down_interface(interface);

2457

if(ret_errno != 0){

2458

errno = ret_errno;

2459

perror_plus("Failed to take down interface");

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2460

1992

}

2461

1993

}

2462

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

2463

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

2464

" down\n");

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2465

2003

}

2466

2004

}

2467

2468

lower_privileges_permanently();

2469

2005

}

2470

2006

2471

free(interfaces_to_take_down);

2472

free(interfaces_hooks);

2473

2474

2007

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

2475

2008

if(tempdir_created){

2476

2009

struct dirent **direntries = NULL;

2489

2022

}

2490

2023

ret = remove(fullname);

2491

2024

if(ret == -1){

2492

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

2493

strerror(errno));

2025

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

2026

strerror(errno));

2494

2027

}

2495

2028

free(fullname);

2496

2029

}