/mandos/trunk : revision 369

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

26

* along with this program. If not, see

27

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

28

*

29

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

29

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

30

*/

31

32

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

41

42

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

43

stdout, ferror(), remove() */

44

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

44

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

45

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

46

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

47

strtof(), abort() */

46

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

47

srand(), strtof() */

48

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

49

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

50

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

53

sockaddr_in6, PF_INET6,

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

56

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

56

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

57

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

58

inet_pton(), connect() */

59

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

62

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

63

strtoimax() */

64

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

65

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

66

program_invocation_short_name */

67

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

65

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

66

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

68

67

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

69

68

SIOCSIFFLAGS, if_indextoname(),

70

69

if_nametoindex(), IF_NAMESIZE */

73

72

*/

74

73

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

75

74

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

76

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

77

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

75

setgid() */

76

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

78

77

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

79

78

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

80

79

argp_state, struct argp,

83

82

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

84

83

sigaction(), SIGTERM, sig_atomic_t,

85

84

raise() */

86

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

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

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

89

WEXITSTATUS(), WTERMSIG() */

90

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

91

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

92

argz_delete(), argz_append(),

93

argz_stringify(), argz_add(),

94

argz_count() */

95

85

96

86

#ifdef __linux__

97

87

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

115

105

init_gnutls_session(),

116

106

GNUTLS_* */

117

107

#include <gnutls/openpgp.h>

118

/* gnutls_certificate_set_openpgp_key_file(),

119

GNUTLS_OPENPGP_FMT_BASE64 */

108

/* gnutls_certificate_set_openpgp_key_file(),

109

GNUTLS_OPENPGP_FMT_BASE64 */

120

110

121

111

/* GPGME */

122

112

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

130

120

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

131

121

#define SECKEY "seckey.txt"

132

122

#define PUBKEY "pubkey.txt"

133

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

134

123

135

124

bool debug = false;

136

125

static const char mandos_protocol_version[] = "1";

137

126

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

138

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

139

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

140

char *connect_to = NULL;

141

const char *hookdir = HOOKDIR;

142

uid_t uid = 65534;

143

gid_t gid = 65534;

144

145

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

146

typedef struct server{

147

const char *ip;

148

uint16_t port;

149

AvahiIfIndex if_index;

150

int af;

151

struct timespec last_seen;

152

struct server *next;

153

struct server *prev;

154

} server;

127

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

155

128

156

129

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

157

130

typedef struct {

162

135

gnutls_dh_params_t dh_params;

163

136

const char *priority;

164

137

gpgme_ctx_t ctx;

165

server *current_server;

166

138

} mandos_context;

167

139

168

140

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

169

141

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

170

142

.dh_bits = 1024, .priority = "SECURE256"

171

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

172

.current_server = NULL };

173

174

sig_atomic_t quit_now = 0;

175

int signal_received = 0;

176

177

/* Function to use when printing errors */

178

void perror_plus(const char *print_text){

179

int e = errno;

180

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

181

program_invocation_short_name);

182

errno = e;

183

perror(print_text);

184

}

185

186

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

187

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

188

va_list ap;

189

va_start (ap, format);

190

191

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

192

program_invocation_short_name));

193

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

194

}

143

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

195

144

196

145

/*

197

146

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

199

148

* "buffer_length" is how much is already used.

200

149

*/

201

150

size_t incbuffer(char **buffer, size_t buffer_length,

202

size_t buffer_capacity){

151

size_t buffer_capacity){

203

152

if(buffer_length + BUFFER_SIZE > buffer_capacity){

204

153

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

205

154

if(buffer == NULL){

210

159

return buffer_capacity;

211

160

}

212

161

213

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

214

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

215

int af){

216

int ret;

217

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

218

if(new_server == NULL){

219

perror_plus("malloc");

220

return false;

221

}

222

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

223

.port = port,

224

.if_index = if_index,

225

.af = af };

226

if(new_server->ip == NULL){

227

perror_plus("strdup");

228

return false;

229

}

230

/* Special case of first server */

231

if (mc.current_server == NULL){

232

new_server->next = new_server;

233

new_server->prev = new_server;

234

mc.current_server = new_server;

235

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

236

} else {

237

new_server->next = mc.current_server;

238

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

239

new_server->prev->next = new_server;

240

mc.current_server->prev = new_server;

241

}

242

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

243

if(ret == -1){

244

perror_plus("clock_gettime");

245

return false;

246

}

247

return true;

248

}

249

250

162

/*

251

163

* Initialize GPGME.

252

164

*/

253

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

254

const char *tempdir){

165

static bool init_gpgme(const char *seckey,

166

const char *pubkey, const char *tempdir){

255

167

gpgme_error_t rc;

256

168

gpgme_engine_info_t engine_info;

257

169

266

178

267

179

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

268

180

if(fd == -1){

269

perror_plus("open");

181

perror("open");

270

182

return false;

271

183

}

272

184

273

185

rc = gpgme_data_new_from_fd(&pgp_data, fd);

274

186

if(rc != GPG_ERR_NO_ERROR){

275

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

276

gpgme_strsource(rc), gpgme_strerror(rc));

187

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

188

gpgme_strsource(rc), gpgme_strerror(rc));

277

189

return false;

278

190

}

279

191

280

192

rc = gpgme_op_import(mc.ctx, pgp_data);

281

193

if(rc != GPG_ERR_NO_ERROR){

282

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

283

gpgme_strsource(rc), gpgme_strerror(rc));

194

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

195

gpgme_strsource(rc), gpgme_strerror(rc));

284

196

return false;

285

197

}

286

198

287

199

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

288

200

if(ret == -1){

289

perror_plus("close");

201

perror("close");

290

202

}

291

203

gpgme_data_release(pgp_data);

292

204

return true;

293

205

}

294

206

295

207

if(debug){

296

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

208

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

297

209

}

298

210

299

211

/* Init GPGME */

300

212

gpgme_check_version(NULL);

301

213

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

302

214

if(rc != GPG_ERR_NO_ERROR){

303

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

304

gpgme_strsource(rc), gpgme_strerror(rc));

215

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

216

gpgme_strsource(rc), gpgme_strerror(rc));

305

217

return false;

306

218

}

307

219

308

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

220

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

309

221

rc = gpgme_get_engine_info(&engine_info);

310

222

if(rc != GPG_ERR_NO_ERROR){

311

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

312

gpgme_strsource(rc), gpgme_strerror(rc));

223

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

224

gpgme_strsource(rc), gpgme_strerror(rc));

313

225

return false;

314

226

}

315

227

while(engine_info != NULL){

321

233

engine_info = engine_info->next;

322

234

}

323

235

if(engine_info == NULL){

324

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

325

tempdir);

236

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

326

237

return false;

327

238

}

328

239

329

240

/* Create new GPGME "context" */

330

241

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

331

242

if(rc != GPG_ERR_NO_ERROR){

332

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

333

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

334

gpgme_strerror(rc));

243

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

244

gpgme_strsource(rc), gpgme_strerror(rc));

335

245

return false;

336

246

}

337

247

356

266

ssize_t plaintext_length = 0;

357

267

358

268

if(debug){

359

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

269

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

360

270

}

361

271

362

272

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

363

273

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

364

274

0);

365

275

if(rc != GPG_ERR_NO_ERROR){

366

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

367

gpgme_strsource(rc), gpgme_strerror(rc));

276

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

277

gpgme_strsource(rc), gpgme_strerror(rc));

368

278

return -1;

369

279

}

370

280

371

281

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

372

282

rc = gpgme_data_new(&dh_plain);

373

283

if(rc != GPG_ERR_NO_ERROR){

374

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

375

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

376

gpgme_strsource(rc), gpgme_strerror(rc));

284

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

285

gpgme_strsource(rc), gpgme_strerror(rc));

377

286

gpgme_data_release(dh_crypto);

378

287

return -1;

379

288

}

382

291

data buffer */

383

292

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

384

293

if(rc != GPG_ERR_NO_ERROR){

385

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

386

gpgme_strsource(rc), gpgme_strerror(rc));

294

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

295

gpgme_strsource(rc), gpgme_strerror(rc));

387

296

plaintext_length = -1;

388

297

if(debug){

389

298

gpgme_decrypt_result_t result;

390

299

result = gpgme_op_decrypt_result(mc.ctx);

391

300

if(result == NULL){

392

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

301

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

393

302

} else {

394

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

395

result->unsupported_algorithm);

396

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

397

result->wrong_key_usage);

303

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

304

result->unsupported_algorithm);

305

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

306

result->wrong_key_usage);

398

307

if(result->file_name != NULL){

399

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

308

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

400

309

}

401

310

gpgme_recipient_t recipient;

402

311

recipient = result->recipients;

403

312

while(recipient != NULL){

404

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

405

gpgme_pubkey_algo_name

406

(recipient->pubkey_algo));

407

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

408

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

409

recipient->status == GPG_ERR_NO_SECKEY

410

? "No" : "Yes");

313

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

314

gpgme_pubkey_algo_name(recipient->pubkey_algo));

315

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

316

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

317

recipient->status == GPG_ERR_NO_SECKEY

318

? "No" : "Yes");

411

319

recipient = recipient->next;

412

320

}

413

321

}

416

324

}

417

325

418

326

if(debug){

419

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

327

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

420

328

}

421

329

422

330

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

423

331

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

424

perror_plus("gpgme_data_seek");

332

perror("gpgme_data_seek");

425

333

plaintext_length = -1;

426

334

goto decrypt_end;

427

335

}

429

337

*plaintext = NULL;

430

338

while(true){

431

339

plaintext_capacity = incbuffer(plaintext,

432

(size_t)plaintext_length,

433

plaintext_capacity);

340

(size_t)plaintext_length,

341

plaintext_capacity);

434

342

if(plaintext_capacity == 0){

435

perror_plus("incbuffer");

436

plaintext_length = -1;

437

goto decrypt_end;

343

perror("incbuffer");

344

plaintext_length = -1;

345

goto decrypt_end;

438

346

}

439

347

440

348

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

445

353

break;

446

354

}

447

355

if(ret < 0){

448

perror_plus("gpgme_data_read");

356

perror("gpgme_data_read");

449

357

plaintext_length = -1;

450

358

goto decrypt_end;

451

359

}

453

361

}

454

362

455

363

if(debug){

456

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

364

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

457

365

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

458

366

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

459

367

}

481

389

/* GnuTLS log function callback */

482

390

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

483

391

const char* string){

484

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

392

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

485

393

}

486

394

487

395

static int init_gnutls_global(const char *pubkeyfilename,

489

397

int ret;

490

398

491

399

if(debug){

492

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

400

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

493

401

}

494

402

495

403

ret = gnutls_global_init();

496

404

if(ret != GNUTLS_E_SUCCESS){

497

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

498

safer_gnutls_strerror(ret));

405

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

406

safer_gnutls_strerror(ret));

499

407

return -1;

500

408

}

501

409

508

416

}

509

417

510

418

/* OpenPGP credentials */

511

ret = gnutls_certificate_allocate_credentials(&mc.cred);

419

gnutls_certificate_allocate_credentials(&mc.cred);

512

420

if(ret != GNUTLS_E_SUCCESS){

513

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

514

safer_gnutls_strerror(ret));

421

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

422

from

423

-Wunreachable-code

424

*/

425

safer_gnutls_strerror(ret));

515

426

gnutls_global_deinit();

516

427

return -1;

517

428

}

518

429

519

430

if(debug){

520

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

521

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

522

pubkeyfilename,

523

seckeyfilename);

431

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

432

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

433

seckeyfilename);

524

434

}

525

435

526

436

ret = gnutls_certificate_set_openpgp_key_file

527

437

(mc.cred, pubkeyfilename, seckeyfilename,

528

438

GNUTLS_OPENPGP_FMT_BASE64);

529

439

if(ret != GNUTLS_E_SUCCESS){

530

fprintf_plus(stderr,

531

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

532

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

533

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

534

safer_gnutls_strerror(ret));

440

fprintf(stderr,

441

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

442

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

443

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

444

safer_gnutls_strerror(ret));

535

445

goto globalfail;

536

446

}

537

447

538

448

/* GnuTLS server initialization */

539

449

ret = gnutls_dh_params_init(&mc.dh_params);

540

450

if(ret != GNUTLS_E_SUCCESS){

541

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

542

" initialization: %s\n",

543

safer_gnutls_strerror(ret));

451

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

452

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

544

453

goto globalfail;

545

454

}

546

455

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

547

456

if(ret != GNUTLS_E_SUCCESS){

548

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

549

safer_gnutls_strerror(ret));

457

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

458

safer_gnutls_strerror(ret));

550

459

goto globalfail;

551

460

}

552

461

567

476

/* GnuTLS session creation */

568

477

do {

569

478

ret = gnutls_init(session, GNUTLS_SERVER);

570

if(quit_now){

571

return -1;

572

}

573

479

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

574

480

if(ret != GNUTLS_E_SUCCESS){

575

fprintf_plus(stderr,

576

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

577

safer_gnutls_strerror(ret));

481

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

482

safer_gnutls_strerror(ret));

578

483

}

579

484

580

485

{

581

486

const char *err;

582

487

do {

583

488

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

584

if(quit_now){

585

gnutls_deinit(*session);

586

return -1;

587

}

588

489

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

589

490

if(ret != GNUTLS_E_SUCCESS){

590

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

591

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

592

safer_gnutls_strerror(ret));

491

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

492

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

493

safer_gnutls_strerror(ret));

593

494

gnutls_deinit(*session);

594

495

return -1;

595

496

}

598

499

do {

599

500

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

600

501

mc.cred);

601

if(quit_now){

602

gnutls_deinit(*session);

603

return -1;

604

}

605

502

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

606

503

if(ret != GNUTLS_E_SUCCESS){

607

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

608

safer_gnutls_strerror(ret));

504

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

505

safer_gnutls_strerror(ret));

609

506

gnutls_deinit(*session);

610

507

return -1;

611

508

}

622

519

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

623

520

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

624

521

522

sig_atomic_t quit_now = 0;

523

int signal_received = 0;

524

625

525

/* Called when a Mandos server is found */

626

526

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

627

527

AvahiIfIndex if_index,

633

533

struct sockaddr_in6 in6;

634

534

} to;

635

535

char *buffer = NULL;

636

char *decrypted_buffer = NULL;

536

char *decrypted_buffer;

637

537

size_t buffer_length = 0;

638

538

size_t buffer_capacity = 0;

639

539

size_t written;

640

int retval = -1;

540

int retval = 0;

641

541

gnutls_session_t session;

642

542

int pf; /* Protocol family */

643

543

644

errno = 0;

645

646

544

if(quit_now){

647

errno = EINTR;

648

545

return -1;

649

546

}

650

547

656

553

pf = PF_INET;

657

554

break;

658

555

default:

659

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

660

errno = EINVAL;

556

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

661

557

return -1;

662

558

}

663

559

667

563

}

668

564

669

565

if(debug){

670

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

671

PRIu16 "\n", ip, port);

566

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

567

"\n", ip, port);

672

568

}

673

569

674

570

tcp_sd = socket(pf, SOCK_STREAM, 0);

675

571

if(tcp_sd < 0){

676

int e = errno;

677

perror_plus("socket");

678

errno = e;

572

perror("socket");

573

retval = -1;

679

574

goto mandos_end;

680

575

}

681

576

682

577

if(quit_now){

683

errno = EINTR;

684

578

goto mandos_end;

685

579

}

686

580

693

587

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

694

588

}

695

589

if(ret < 0 ){

696

int e = errno;

697

perror_plus("inet_pton");

698

errno = e;

590

perror("inet_pton");

591

retval = -1;

699

592

goto mandos_end;

700

593

}

701

594

if(ret == 0){

702

int e = errno;

703

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

704

errno = e;

595

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

596

retval = -1;

705

597

goto mandos_end;

706

598

}

707

599

if(af == AF_INET6){

711

603

712

604

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

713

605

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

714

-Wunreachable-code*/

606

-Wunreachable-code*/

715

607

if(if_index == AVAHI_IF_UNSPEC){

716

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

717

" incomplete without a network interface\n");

718

errno = EINVAL;

608

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

609

" without a network interface\n");

610

retval = -1;

719

611

goto mandos_end;

720

612

}

721

613

/* Set the network interface number as scope */

728

620

}

729

621

730

622

if(quit_now){

731

errno = EINTR;

732

623

goto mandos_end;

733

624

}

734

625

736

627

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

737

628

char interface[IF_NAMESIZE];

738

629

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

739

perror_plus("if_indextoname");

630

perror("if_indextoname");

740

631

} else {

741

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

742

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

632

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

633

ip, interface, port);

743

634

}

744

635

} else {

745

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

746

ip, port);

636

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

637

port);

747

638

}

748

639

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

749

640

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

756

647

sizeof(addrstr));

757

648

}

758

649

if(pcret == NULL){

759

perror_plus("inet_ntop");

650

perror("inet_ntop");

760

651

} else {

761

652

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

762

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

653

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

763

654

}

764

655

}

765

656

}

766

657

767

658

if(quit_now){

768

errno = EINTR;

769

659

goto mandos_end;

770

660

}

771

661

775

665

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

776

666

}

777

667

if(ret < 0){

778

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

779

int e = errno;

780

perror_plus("connect");

781

errno = e;

782

}

668

perror("connect");

669

retval = -1;

783

670

goto mandos_end;

784

671

}

785

672

786

673

if(quit_now){

787

errno = EINTR;

788

674

goto mandos_end;

789

675

}

790

676

793

679

while(true){

794

680

size_t out_size = strlen(out);

795

681

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

796

out_size - written));

682

out_size - written));

797

683

if(ret == -1){

798

int e = errno;

799

perror_plus("write");

800

errno = e;

684

perror("write");

685

retval = -1;

801

686

goto mandos_end;

802

687

}

803

688

written += (size_t)ret;

813

698

}

814

699

815

700

if(quit_now){

816

errno = EINTR;

817

701

goto mandos_end;

818

702

}

819

703

}

820

704

821

705

if(debug){

822

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

706

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

823

707

}

824

708

825

709

if(quit_now){

826

errno = EINTR;

827

710

goto mandos_end;

828

711

}

829

712

830

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

831

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

832

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

833

gnutls_transport_set_ptr(session,

834

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

713

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

835

714

836

715

if(quit_now){

837

errno = EINTR;

838

716

goto mandos_end;

839

717

}

840

718

841

719

do {

842

720

ret = gnutls_handshake(session);

843

721

if(quit_now){

844

errno = EINTR;

845

722

goto mandos_end;

846

723

}

847

724

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

848

725

849

726

if(ret != GNUTLS_E_SUCCESS){

850

727

if(debug){

851

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

728

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

852

729

gnutls_perror(ret);

853

730

}

854

errno = EPROTO;

731

retval = -1;

855

732

goto mandos_end;

856

733

}

857

734

858

735

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

859

736

860

737

if(debug){

861

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

862

" %s\n", ip);

738

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

739

ip);

863

740

}

864

741

865

742

while(true){

866

743

867

744

if(quit_now){

868

errno = EINTR;

869

745

goto mandos_end;

870

746

}

871

747

872

748

buffer_capacity = incbuffer(&buffer, buffer_length,

873

buffer_capacity);

749

buffer_capacity);

874

750

if(buffer_capacity == 0){

875

int e = errno;

876

perror_plus("incbuffer");

877

errno = e;

751

perror("incbuffer");

752

retval = -1;

878

753

goto mandos_end;

879

754

}

880

755

881

756

if(quit_now){

882

errno = EINTR;

883

757

goto mandos_end;

884

758

}

885

759

898

772

ret = gnutls_handshake(session);

899

773

900

774

if(quit_now){

901

errno = EINTR;

902

775

goto mandos_end;

903

776

}

904

777

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

905

778

if(ret < 0){

906

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

907

"***\n");

779

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

908

780

gnutls_perror(ret);

909

errno = EPROTO;

781

retval = -1;

910

782

goto mandos_end;

911

783

}

912

784

break;

913

785

default:

914

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

915

" encrypted session with Mandos server\n");

786

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

787

" encrypted session with Mandos server\n");

788

retval = -1;

916

789

gnutls_bye(session, GNUTLS_SHUT_RDWR);

917

errno = EIO;

918

790

goto mandos_end;

919

791

}

920

792

} else {

923

795

}

924

796

925

797

if(debug){

926

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

927

}

928

929

if(quit_now){

930

errno = EINTR;

931

goto mandos_end;

932

}

933

934

do {

935

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

936

if(quit_now){

937

errno = EINTR;

938

goto mandos_end;

939

}

940

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

798

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

799

}

800

801

if(quit_now){

802

goto mandos_end;

803

}

804

805

gnutls_bye(session, GNUTLS_SHUT_RDWR);

806

807

if(quit_now){

808

goto mandos_end;

809

}

941

810

942

811

if(buffer_length > 0){

943

812

ssize_t decrypted_buffer_size;

944

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

813

decrypted_buffer_size = pgp_packet_decrypt(buffer,

814

buffer_length,

945

815

&decrypted_buffer);

946

816

if(decrypted_buffer_size >= 0){

947

817

948

818

written = 0;

949

819

while(written < (size_t) decrypted_buffer_size){

950

820

if(quit_now){

951

errno = EINTR;

952

821

goto mandos_end;

953

822

}

954

823

956

825

(size_t)decrypted_buffer_size - written,

957

826

stdout);

958

827

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

959

int e = errno;

960

828

if(debug){

961

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

962

strerror(errno));

829

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

830

strerror(errno));

963

831

}

964

errno = e;

965

goto mandos_end;

832

retval = -1;

833

break;

966

834

}

967

835

written += (size_t)ret;

968

836

}

969

retval = 0;

837

free(decrypted_buffer);

838

} else {

839

retval = -1;

970

840

}

841

} else {

842

retval = -1;

971

843

}

972

844

973

845

/* Shutdown procedure */

974

846

975

847

mandos_end:

976

{

977

int e = errno;

978

free(decrypted_buffer);

979

free(buffer);

980

if(tcp_sd >= 0){

981

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

982

}

983

if(ret == -1){

984

if(e == 0){

985

e = errno;

986

}

987

perror_plus("close");

988

}

989

gnutls_deinit(session);

990

errno = e;

991

if(quit_now){

992

errno = EINTR;

993

retval = -1;

994

}

848

free(buffer);

849

if(tcp_sd >= 0){

850

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

851

}

852

if(ret == -1){

853

perror("close");

854

}

855

gnutls_deinit(session);

856

if(quit_now){

857

retval = -1;

995

858

}

996

859

return retval;

997

860

}

1022

885

switch(event){

1023

886

default:

1024

887

case AVAHI_RESOLVER_FAILURE:

1025

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

1026

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

1027

domain,

1028

avahi_strerror(avahi_server_errno(mc.server)));

888

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

889

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

890

avahi_strerror(avahi_server_errno(mc.server)));

1029

891

break;

1030

892

1031

893

case AVAHI_RESOLVER_FOUND:

1033

895

char ip[AVAHI_ADDRESS_STR_MAX];

1034

896

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

1035

897

if(debug){

1036

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

1037

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

1038

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

898

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

899

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

900

ip, (intmax_t)interface, port);

1039

901

}

1040

902

int ret = start_mandos_communication(ip, port, interface,

1041

903

avahi_proto_to_af(proto));

1042

904

if(ret == 0){

1043

905

avahi_simple_poll_quit(mc.simple_poll);

1044

} else {

1045

if(not add_server(ip, port, interface,

1046

avahi_proto_to_af(proto))){

1047

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

1048

" list\n", name);

1049

}

1050

906

}

1051

907

}

1052

908

}

1076

932

default:

1077

933

case AVAHI_BROWSER_FAILURE:

1078

934

1079

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

935

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

936

avahi_strerror(avahi_server_errno(mc.server)));

1081

937

avahi_simple_poll_quit(mc.simple_poll);

1082

938

return;

1083

939

1090

946

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

1091

947

name, type, domain, protocol, 0,

1092

948

resolve_callback, NULL) == NULL)

1093

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

1094

" %s\n", name,

1095

avahi_strerror(avahi_server_errno(mc.server)));

949

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

950

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

1096

951

break;

1097

952

1098

953

case AVAHI_BROWSER_REMOVE:

1101

956

case AVAHI_BROWSER_ALL_FOR_NOW:

1102

957

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1103

958

if(debug){

1104

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

1105

" searching...\n");

959

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

1106

960

}

1107

961

break;

1108

962

}

1109

963

}

1110

964

1111

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

965

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

1112

966

static void handle_sigterm(int sig){

1113

967

if(quit_now){

1114

968

return;

1116

970

quit_now = 1;

1117

971

signal_received = sig;

1118

972

int old_errno = errno;

1119

/* set main loop to exit */

1120

973

if(mc.simple_poll != NULL){

1121

974

avahi_simple_poll_quit(mc.simple_poll);

1122

975

}

1123

976

errno = old_errno;

1124

977

}

1125

978

1126

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

1127

int ret;

1128

error_t ret_errno;

1129

1130

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

1131

if(s < 0){

1132

ret_errno = errno;

1133

perror_plus("socket");

1134

errno = ret_errno;

1135

return false;

1136

}

1137

strcpy(ifr->ifr_name, ifname);

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1139

if(ret == -1){

1140

if(debug){

1141

ret_errno = errno;

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1144

}

1145

return false;

1146

}

1147

return true;

1148

}

1149

1150

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

1151

1152

/* Reject the loopback device */

1153

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

ifname);

1157

}

1158

return false;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

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

1165

}

1166

return true;

1167

}

1168

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

1169

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

1170

if(debug){

1171

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1172

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

1173

}

1174

return false;

1175

}

1176

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

1177

if(ifr->ifr_flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

ifname);

1181

}

1182

return false;

1183

}

1184

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

}

1189

return true;

1190

}

1191

1192

/*

1193

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

1194

* corresponds to an acceptable network device.

1195

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

1196

*/

1197

int good_interface(const struct dirent *if_entry){

1198

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

1199

return 0;

1200

}

1201

1202

struct ifreq ifr;

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1208

return 0;

1209

}

1210

1211

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

1212

return 0;

1213

}

1214

return 1;

1215

}

1216

1217

/*

1218

* This function determines if a network interface is up.

1219

*/

1220

bool interface_is_up(const char *interface){

1221

struct ifreq ifr;

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return false;

1228

}

1229

1230

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

1231

}

1232

1233

/*

1234

* This function determines if a network interface is running

1235

*/

1236

bool interface_is_running(const char *interface){

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return false;

1244

}

1245

1246

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

1247

}

1248

1249

int notdotentries(const struct dirent *direntry){

1250

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

1251

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

1252

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

1253

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

1254

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

1255

return 0;

1256

}

1257

return 1;

1258

}

1259

1260

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

1261

int runnable_hook(const struct dirent *direntry){

1262

int ret;

1263

size_t sret;

1264

struct stat st;

1265

1266

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

1267

/* Empty name? */

1268

return 0;

1269

}

1270

1271

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

1272

"abcdefghijklmnopqrstuvwxyz"

1273

"0123456789"

1274

"_-");

1275

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

1276

/* Contains non-allowed characters */

1277

if(debug){

1278

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

1279

direntry->d_name);

1280

}

1281

return 0;

1282

}

1283

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1292

if(ret == -1){

1293

if(debug){

1294

perror_plus("Could not stat hook");

1295

}

1296

return 0;

1297

}

1298

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

1299

/* Not a regular file */

1300

if(debug){

1301

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

1302

direntry->d_name);

1303

}

1304

return 0;

1305

}

1306

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

1307

/* Not executable */

1308

if(debug){

1309

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

1310

direntry->d_name);

1311

}

1312

return 0;

1313

}

1314

if(debug){

1315

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

1316

direntry->d_name);

1317

}

1318

return 1;

1319

}

1320

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1322

int ret;

1323

struct timespec now;

1324

struct timespec waited_time;

1325

intmax_t block_time;

1326

1327

while(true){

1328

if(mc.current_server == NULL){

1329

if (debug){

1330

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

1331

" No timeout!\n");

1332

}

1333

ret = avahi_simple_poll_iterate(s, -1);

1334

} else {

1335

if (debug){

1336

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

1337

" it, or wait\n");

1338

}

1339

/* the current time */

1340

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1341

if(ret == -1){

1342

perror_plus("clock_gettime");

1343

return -1;

1344

}

1345

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

1346

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

1347

waited_time.tv_sec = (now.tv_sec

1348

- mc.current_server->last_seen.tv_sec);

1349

waited_time.tv_nsec = (now.tv_nsec

1350

- mc.current_server->last_seen.tv_nsec);

1351

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

1352

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

1353

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

1354

block_time = ((retry_interval

1355

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

1356

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

1357

1358

if (debug){

1359

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

1360

block_time);

1361

}

1362

1363

if(block_time <= 0){

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1368

if(ret == 0){

1369

avahi_simple_poll_quit(mc.simple_poll);

1370

return 0;

1371

}

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1373

&mc.current_server->last_seen);

1374

if(ret == -1){

1375

perror_plus("clock_gettime");

1376

return -1;

1377

}

1378

mc.current_server = mc.current_server->next;

1379

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

1380

servers, but don't block */

1381

}

1382

1383

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

1384

}

1385

if(ret != 0){

1386

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

1387

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

1388

}

1389

}

1390

}

1391

}

1392

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1445

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

1446

const float delay){

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1452

if(numhooks == -1){

1453

perror_plus("scandir");

1454

} else {

1455

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

1456

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

1457

direntry = direntries[i];

1458

char *fullname = NULL;

1459

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

1460

if(ret < 0){

1461

perror_plus("asprintf");

1462

continue;

1463

}

1464

if(debug){

1465

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

1466

direntry->d_name);

1467

}

1468

pid_t hook_pid = fork();

1469

if(hook_pid == 0){

1470

/* Child */

1471

/* Raise privileges */

1472

raise_privileges_permanently();

1473

/* Set group */

1474

errno = 0;

1475

ret = setgid(0);

1476

if(ret == -1){

1477

perror_plus("setgid");

1478

}

1479

/* Reset supplementary groups */

1480

errno = 0;

1481

ret = setgroups(0, NULL);

1482

if(ret == -1){

1483

perror_plus("setgroups");

1484

}

1485

dup2(devnull, STDIN_FILENO);

1486

close(devnull);

1487

dup2(STDERR_FILENO, STDOUT_FILENO);

1488

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

1489

if(ret == -1){

1490

perror_plus("setenv");

1491

_exit(EX_OSERR);

1492

}

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

char *delaystring;

1509

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

1510

if(ret == -1){

1511

perror_plus("asprintf");

1512

_exit(EX_OSERR);

1513

}

1514

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

1515

if(ret == -1){

1516

free(delaystring);

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

free(delaystring);

1521

if(connect_to != NULL){

1522

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

1523

if(ret == -1){

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1527

}

1528

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

1529

perror_plus("execl");

1530

_exit(EXIT_FAILURE);

1531

}

1532

} else {

1533

int status;

1534

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

1535

perror_plus("waitpid");

1536

free(fullname);

1537

continue;

1538

}

1539

if(WIFEXITED(status)){

1540

if(WEXITSTATUS(status) != 0){

1541

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

1542

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

1543

WEXITSTATUS(status));

1544

free(fullname);

1545

continue;

1546

}

1547

} else if(WIFSIGNALED(status)){

1548

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

1549

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

1550

WTERMSIG(status));

1551

free(fullname);

1552

continue;

1553

} else {

1554

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

1555

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

1556

free(fullname);

1557

continue;

1558

}

1559

}

1560

free(fullname);

1561

if(debug){

1562

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

1563

direntry->d_name);

1564

}

1565

}

1566

close(devnull);

1567

}

1568

return true;

1569

}

1570

1571

error_t bring_up_interface(const char *const interface,

1572

const float delay){

1573

int sd = -1;

1574

error_t old_errno = errno;

1575

error_t ret_errno = 0;

1576

int ret, ret_setflags;

1577

struct ifreq network;

1578

unsigned int if_index = if_nametoindex(interface);

1579

if(if_index == 0){

1580

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

1581

errno = old_errno;

1582

return ENXIO;

1583

}

1584

1585

if(quit_now){

1586

errno = old_errno;

1587

return EINTR;

1588

}

1589

1590

if(not interface_is_up(interface)){

1591

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

1592

ret_errno = errno;

1593

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

1594

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

1595

return ret_errno;

1596

}

1597

network.ifr_flags |= IFF_UP;

1598

1599

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1600

if(sd < 0){

1601

ret_errno = errno;

1602

perror_plus("socket");

1603

errno = old_errno;

1604

return ret_errno;

1605

}

1606

1607

if(quit_now){

1608

close(sd);

1609

errno = old_errno;

1610

return EINTR;

1611

}

1612

1613

if(debug){

1614

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

1615

interface);

1616

}

1617

1618

/* Raise priviliges */

1619

raise_privileges();

1620

1621

#ifdef __linux__

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

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

1625

bool restore_loglevel = true;

1626

if(ret_linux == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1629

}

1630

#endif /* __linux__ */

1631

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

1632

ret_errno = errno;

1633

#ifdef __linux__

1634

if(restore_loglevel){

1635

ret_linux = klogctl(7, NULL, 0);

1636

if(ret_linux == -1){

1637

perror_plus("klogctl");

1638

}

1639

}

1640

#endif /* __linux__ */

1641

1642

/* Lower privileges */

1643

lower_privileges();

1644

1645

/* Close the socket */

1646

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

1647

if(ret == -1){

1648

perror_plus("close");

1649

}

1650

1651

if(ret_setflags == -1){

1652

errno = ret_errno;

1653

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1654

errno = old_errno;

1655

return ret_errno;

1656

}

1657

} else if(debug){

1658

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

1659

interface);

1660

}

1661

1662

/* Sleep checking until interface is running.

1663

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

1664

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

1665

if(interface_is_running(interface)){

1666

break;

1667

}

1668

struct timespec sleeptime = { .tv_nsec = 250000000 };

1669

ret = nanosleep(&sleeptime, NULL);

1670

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

1671

perror_plus("nanosleep");

1672

}

1673

}

1674

1675

errno = old_errno;

1676

return 0;

1677

}

1678

1679

error_t take_down_interface(const char *const interface){

1680

int sd = -1;

1681

error_t old_errno = errno;

1682

error_t ret_errno = 0;

1683

int ret, ret_setflags;

1684

struct ifreq network;

1685

unsigned int if_index = if_nametoindex(interface);

1686

if(if_index == 0){

1687

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

1688

errno = old_errno;

1689

return ENXIO;

1690

}

1691

if(interface_is_up(interface)){

1692

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

1693

ret_errno = errno;

1694

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

1695

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

1696

return ret_errno;

1697

}

1698

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

1699

1700

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1701

if(sd < 0){

1702

ret_errno = errno;

1703

perror_plus("socket");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

1708

if(debug){

1709

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

1710

interface);

1711

}

1712

1713

/* Raise priviliges */

1714

raise_privileges();

1715

1716

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

1717

ret_errno = errno;

1718

1719

/* Lower privileges */

1720

lower_privileges();

1721

1722

/* Close the socket */

1723

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

1724

if(ret == -1){

1725

perror_plus("close");

1726

}

1727

1728

if(ret_setflags == -1){

1729

errno = ret_errno;

1730

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1731

errno = old_errno;

1732

return ret_errno;

1733

}

1734

} else if(debug){

1735

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

1736

interface);

1737

}

1738

1739

errno = old_errno;

1740

return 0;

1741

}

1742

1743

979

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

1744

980

AvahiSServiceBrowser *sb = NULL;

1745

error_t ret_errno;

981

int error;

1746

982

int ret;

1747

983

intmax_t tmpmax;

1748

984

char *tmp;

1749

985

int exitcode = EXIT_SUCCESS;

1750

char *interfaces = NULL;

1751

size_t interfaces_size = 0;

1752

char *interfaces_to_take_down = NULL;

1753

size_t interfaces_to_take_down_size = 0;

986

const char *interface = "eth0";

987

struct ifreq network;

988

int sd = -1;

989

bool take_down_interface = false;

990

uid_t uid;

991

gid_t gid;

992

char *connect_to = NULL;

1754

993

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

1755

994

bool tempdir_created = false;

1756

995

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1757

996

const char *seckey = PATHDIR "/" SECKEY;

1758

997

const char *pubkey = PATHDIR "/" PUBKEY;

1759

char *interfaces_hooks = NULL;

1760

size_t interfaces_hooks_size = 0;

1761

998

1762

999

bool gnutls_initialized = false;

1763

1000

bool gpgme_initialized = false;

1764

1001

float delay = 2.5f;

1765

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

1766

retrying the same server again */

1767

1002

1768

1003

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1769

1004

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1775

1010

errno = 0;

1776

1011

ret = setgid(gid);

1777

1012

if(ret == -1){

1778

perror_plus("setgid");

1013

perror("setgid");

1779

1014

}

1780

1015

1781

1016

/* Lower user privileges (temporarily) */

1782

1017

errno = 0;

1783

1018

ret = seteuid(uid);

1784

1019

if(ret == -1){

1785

perror_plus("seteuid");

1020

perror("seteuid");

1786

1021

}

1787

1022

1788

1023

if(quit_now){

1823

1058

.arg = "SECONDS",

1824

1059

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

1825

1060

.group = 2 },

1826

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

1827

.arg = "SECONDS",

1828

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

1829

.group = 2 },

1830

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

1831

.arg = "DIR",

1832

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

1833

.group = 2 },

1834

/*

1835

* These reproduce what we would get without ARGP_NO_HELP

1836

*/

1837

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

1838

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

1839

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

1840

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

1841

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

1842

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

1843

1061

{ .name = NULL }

1844

1062

};

1845

1063

1846

1064

error_t parse_opt(int key, char *arg,

1847

1065

struct argp_state *state){

1848

errno = 0;

1849

1066

switch(key){

1850

1067

case 128: /* --debug */

1851

1068

debug = true;

1854

1071

connect_to = arg;

1855

1072

break;

1856

1073

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

1857

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

1858

(int)',');

1859

if(ret_errno != 0){

1860

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

1861

}

1074

interface = arg;

1862

1075

break;

1863

1076

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

1864

1077

seckey = arg;

1871

1084

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

1872

1085

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

1873

1086

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

1874

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

1087

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

1088

exit(EXIT_FAILURE);

1875

1089

}

1876

1090

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

1877

1091

break;

1882

1096

errno = 0;

1883

1097

delay = strtof(arg, &tmp);

1884

1098

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

1885

argp_error(state, "Bad delay");

1886

}

1887

case 132: /* --retry */

1888

errno = 0;

1889

retry_interval = strtod(arg, &tmp);

1890

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

1891

or (retry_interval * 1000) > INT_MAX

1892

or retry_interval < 0){

1893

argp_error(state, "Bad retry interval");

1894

}

1895

break;

1896

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

1897

hookdir = arg;

1898

break;

1899

/*

1900

* These reproduce what we would get without ARGP_NO_HELP

1901

*/

1902

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

1903

argp_state_help(state, state->out_stream,

1904

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1905

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1906

case -3: /* --usage */

1907

argp_state_help(state, state->out_stream,

1908

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1909

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

1910

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

1911

exit(argp_err_exit_status);

1099

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

1100

exit(EXIT_FAILURE);

1101

}

1102

break;

1103

case ARGP_KEY_ARG:

1104

argp_usage(state);

1105

case ARGP_KEY_END:

1912

1106

break;

1913

1107

default:

1914

1108

return ARGP_ERR_UNKNOWN;

1915

1109

}

1916

return errno;

1110

return 0;

1917

1111

}

1918

1112

1919

1113

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

1920

1114

.args_doc = "",

1921

1115

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

1922

1116

" passwords from a Mandos server" };

1923

ret = argp_parse(&argp, argc, argv,

1924

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1925

switch(ret){

1926

case 0:

1927

break;

1928

case ENOMEM:

1929

default:

1930

errno = ret;

1931

perror_plus("argp_parse");

1932

exitcode = EX_OSERR;

1933

goto end;

1934

case EINVAL:

1935

exitcode = EX_USAGE;

1936

goto end;

1937

}

1938

}

1939

1940

{

1941

/* Work around Debian bug #633582:

1942

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

1943

1944

/* Re-raise priviliges */

1945

if(raise_privileges() == 0){

1946

struct stat st;

1947

1948

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

1949

int seckey_fd = open(seckey, O_RDONLY);

1950

if(seckey_fd == -1){

1951

perror_plus("open");

1952

} else {

1953

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

1954

if(ret == -1){

1955

perror_plus("fstat");

1956

} else {

1957

if(S_ISREG(st.st_mode)

1958

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

1959

ret = fchown(seckey_fd, uid, gid);

1960

if(ret == -1){

1961

perror_plus("fchown");

1962

}

1963

}

1964

}

1965

TEMP_FAILURE_RETRY(close(seckey_fd));

1966

}

1967

}

1968

1969

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

1970

int pubkey_fd = open(pubkey, O_RDONLY);

1971

if(pubkey_fd == -1){

1972

perror_plus("open");

1973

} else {

1974

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

1975

if(ret == -1){

1976

perror_plus("fstat");

1977

} else {

1978

if(S_ISREG(st.st_mode)

1979

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

1980

ret = fchown(pubkey_fd, uid, gid);

1981

if(ret == -1){

1982

perror_plus("fchown");

1983

}

1984

}

1985

}

1986

TEMP_FAILURE_RETRY(close(pubkey_fd));

1987

}

1988

}

1989

1990

/* Lower privileges */

1991

errno = 0;

1992

ret = seteuid(uid);

1993

if(ret == -1){

1994

perror_plus("seteuid");

1995

}

1996

}

1997

}

1998

1999

/* Remove empty interface names */

2000

{

2001

char *interface = NULL;

2002

while((interface = argz_next(interfaces, interfaces_size,

2003

interface))){

2004

if(if_nametoindex(interface) == 0){

2005

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

2006

fprintf_plus(stderr, "Not using nonexisting interface"

2007

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

2008

}

2009

argz_delete(&interfaces, &interfaces_size, interface);

2010

interface = NULL;

2011

}

2012

}

2013

}

2014

2015

/* Run network hooks */

2016

{

2017

ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,

2018

interfaces, interfaces_size);

2019

if(ret_errno != 0){

2020

errno = ret_errno;

2021

perror_plus("argz_append");

2022

goto end;

2023

}

2024

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

2025

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

1117

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

1118

if(ret == ARGP_ERR_UNKNOWN){

1119

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

1120

exitcode = EXIT_FAILURE;

2026

1121

goto end;

2027

1122

}

2028

1123

}

2037

1132

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

2038

1133

mc.simple_poll = avahi_simple_poll_new();

2039

1134

if(mc.simple_poll == NULL){

2040

fprintf_plus(stderr,

2041

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

2042

exitcode = EX_UNAVAILABLE;

1135

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

1136

exitcode = EXIT_FAILURE;

2043

1137

goto end;

2044

1138

}

2045

1139

2046

1140

sigemptyset(&sigterm_action.sa_mask);

2047

1141

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

2048

1142

if(ret == -1){

2049

perror_plus("sigaddset");

2050

exitcode = EX_OSERR;

1143

perror("sigaddset");

1144

exitcode = EXIT_FAILURE;

2051

1145

goto end;

2052

1146

}

2053

1147

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

2054

1148

if(ret == -1){

2055

perror_plus("sigaddset");

2056

exitcode = EX_OSERR;

1149

perror("sigaddset");

1150

exitcode = EXIT_FAILURE;

2057

1151

goto end;

2058

1152

}

2059

1153

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

2060

1154

if(ret == -1){

2061

perror_plus("sigaddset");

2062

exitcode = EX_OSERR;

1155

perror("sigaddset");

1156

exitcode = EXIT_FAILURE;

2063

1157

goto end;

2064

1158

}

2065

1159

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

2068

1162

*/

2069

1163

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

2070

1164

if(ret == -1){

2071

perror_plus("sigaction");

2072

return EX_OSERR;

1165

perror("sigaction");

1166

return EXIT_FAILURE;

2073

1167

}

2074

1168

if(old_sigterm_action.sa_handler != SIG_IGN){

2075

1169

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

2076

1170

if(ret == -1){

2077

perror_plus("sigaction");

2078

exitcode = EX_OSERR;

1171

perror("sigaction");

1172

exitcode = EXIT_FAILURE;

2079

1173

goto end;

2080

1174

}

2081

1175

}

2082

1176

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

2083

1177

if(ret == -1){

2084

perror_plus("sigaction");

2085

return EX_OSERR;

1178

perror("sigaction");

1179

return EXIT_FAILURE;

2086

1180

}

2087

1181

if(old_sigterm_action.sa_handler != SIG_IGN){

2088

1182

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

2089

1183

if(ret == -1){

2090

perror_plus("sigaction");

2091

exitcode = EX_OSERR;

1184

perror("sigaction");

1185

exitcode = EXIT_FAILURE;

2092

1186

goto end;

2093

1187

}

2094

1188

}

2095

1189

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

2096

1190

if(ret == -1){

2097

perror_plus("sigaction");

2098

return EX_OSERR;

1191

perror("sigaction");

1192

return EXIT_FAILURE;

2099

1193

}

2100

1194

if(old_sigterm_action.sa_handler != SIG_IGN){

2101

1195

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

2102

1196

if(ret == -1){

2103

perror_plus("sigaction");

2104

exitcode = EX_OSERR;

1197

perror("sigaction");

1198

exitcode = EXIT_FAILURE;

2105

1199

goto end;

2106

1200

}

2107

1201

}

2108

1202

2109

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

2110

if(interfaces == NULL){

2111

struct dirent **direntries;

2112

/* Look for any good interfaces */

2113

ret = scandir(sys_class_net, &direntries, good_interface,

2114

alphasort);

2115

if(ret >= 1){

2116

/* Add all found interfaces to interfaces list */

2117

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

2118

ret_errno = argz_add(&interfaces, &interfaces_size,

2119

direntries[i]->d_name);

2120

if(ret_errno != 0){

2121

perror_plus("argz_add");

2122

continue;

2123

}

2124

if(debug){

2125

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

2126

direntries[i]->d_name);

2127

}

2128

}

2129

free(direntries);

1203

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

1204

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

1205

if_index = (AvahiIfIndex) if_nametoindex(interface);

1206

if(if_index == 0){

1207

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

1208

exitcode = EXIT_FAILURE;

1209

goto end;

1210

}

1211

1212

if(quit_now){

1213

goto end;

1214

}

1215

1216

/* Re-raise priviliges */

1217

errno = 0;

1218

ret = seteuid(0);

1219

if(ret == -1){

1220

perror("seteuid");

1221

}

1222

1223

#ifdef __linux__

1224

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1225

messages to mess up the prompt */

1226

ret = klogctl(8, NULL, 5);

1227

bool restore_loglevel = true;

1228

if(ret == -1){

1229

restore_loglevel = false;

1230

perror("klogctl");

1231

}

1232

#endif /* __linux__ */

1233

1234

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1235

if(sd < 0){

1236

perror("socket");

1237

exitcode = EXIT_FAILURE;

1238

#ifdef __linux__

1239

if(restore_loglevel){

1240

ret = klogctl(7, NULL, 0);

1241

if(ret == -1){

1242

perror("klogctl");

1243

}

1244

}

1245

#endif /* __linux__ */

1246

/* Lower privileges */

1247

errno = 0;

1248

ret = seteuid(uid);

1249

if(ret == -1){

1250

perror("seteuid");

1251

}

1252

goto end;

1253

}

1254

strcpy(network.ifr_name, interface);

1255

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

1256

if(ret == -1){

1257

perror("ioctl SIOCGIFFLAGS");

1258

#ifdef __linux__

1259

if(restore_loglevel){

1260

ret = klogctl(7, NULL, 0);

1261

if(ret == -1){

1262

perror("klogctl");

1263

}

1264

}

1265

#endif /* __linux__ */

1266

exitcode = EXIT_FAILURE;

1267

/* Lower privileges */

1268

errno = 0;

1269

ret = seteuid(uid);

1270

if(ret == -1){

1271

perror("seteuid");

1272

}

1273

goto end;

1274

}

1275

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

1276

network.ifr_flags |= IFF_UP;

1277

take_down_interface = true;

1278

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

1279

if(ret == -1){

1280

take_down_interface = false;

1281

perror("ioctl SIOCSIFFLAGS");

1282

exitcode = EXIT_FAILURE;

1283

#ifdef __linux__

1284

if(restore_loglevel){

1285

ret = klogctl(7, NULL, 0);

1286

if(ret == -1){

1287

perror("klogctl");

1288

}

1289

}

1290

#endif /* __linux__ */

1291

/* Lower privileges */

1292

errno = 0;

1293

ret = seteuid(uid);

1294

if(ret == -1){

1295

perror("seteuid");

1296

}

1297

goto end;

1298

}

1299

}

1300

/* sleep checking until interface is running */

1301

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

1302

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

1303

if(ret == -1){

1304

perror("ioctl SIOCGIFFLAGS");

1305

} else if(network.ifr_flags & IFF_RUNNING){

1306

break;

1307

}

1308

struct timespec sleeptime = { .tv_nsec = 250000000 };

1309

ret = nanosleep(&sleeptime, NULL);

1310

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

1311

perror("nanosleep");

1312

}

1313

}

1314

if(not take_down_interface){

1315

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

1316

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

1317

if(ret == -1){

1318

perror("close");

1319

}

1320

}

1321

#ifdef __linux__

1322

if(restore_loglevel){

1323

/* Restores kernel loglevel to default */

1324

ret = klogctl(7, NULL, 0);

1325

if(ret == -1){

1326

perror("klogctl");

1327

}

1328

}

1329

#endif /* __linux__ */

1330

/* Lower privileges */

1331

errno = 0;

1332

if(take_down_interface){

1333

/* Lower privileges */

1334

ret = seteuid(uid);

1335

if(ret == -1){

1336

perror("seteuid");

1337

}

2130

1338

} else {

2131

free(direntries);

2132

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

2133

exitcode = EXIT_FAILURE;

2134

goto end;

2135

}

2136

}

2137

2138

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

2139

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

2140

if(debug){

2141

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

2142

interfaces);

2143

}

2144

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2145

}

2146

2147

/* Bring up interfaces which are down */

2148

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

2149

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

2150

char *interface = NULL;

2151

while((interface = argz_next(interfaces, interfaces_size,

2152

interface))){

2153

bool interface_was_up = interface_is_up(interface);

2154

ret = bring_up_interface(interface, delay);

2155

if(not interface_was_up){

2156

if(ret != 0){

2157

errno = ret;

2158

perror_plus("Failed to bring up interface");

2159

} else {

2160

ret_errno = argz_add(&interfaces_to_take_down,

2161

&interfaces_to_take_down_size,

2162

interface);

2163

}

1339

/* Lower privileges permanently */

1340

ret = setuid(uid);

1341

if(ret == -1){

1342

perror("setuid");

2164

1343

}

2165

1344

}

2166

free(interfaces);

2167

interfaces = NULL;

2168

interfaces_size = 0;

2169

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

2170

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

2171

}

2172

1345

}

2173

1346

2174

1347

if(quit_now){

2177

1350

2178

1351

ret = init_gnutls_global(pubkey, seckey);

2179

1352

if(ret == -1){

2180

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

2181

exitcode = EX_UNAVAILABLE;

1353

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

1354

exitcode = EXIT_FAILURE;

2182

1355

goto end;

2183

1356

} else {

2184

1357

gnutls_initialized = true;

2188

1361

goto end;

2189

1362

}

2190

1363

1364

tempdir_created = true;

2191

1365

if(mkdtemp(tempdir) == NULL){

2192

perror_plus("mkdtemp");

1366

tempdir_created = false;

1367

perror("mkdtemp");

2193

1368

goto end;

2194

1369

}

2195

tempdir_created = true;

2196

1370

2197

1371

if(quit_now){

2198

1372

goto end;

2199

1373

}

2200

1374

2201

1375

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

2202

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

2203

exitcode = EX_UNAVAILABLE;

1376

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

1377

exitcode = EXIT_FAILURE;

2204

1378

goto end;

2205

1379

} else {

2206

1380

gpgme_initialized = true;

2214

1388

/* Connect directly, do not use Zeroconf */

2215

1389

/* (Mainly meant for debugging) */

2216

1390

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

2217

2218

1391

if(address == NULL){

2219

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

2220

exitcode = EX_USAGE;

1392

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

1393

exitcode = EXIT_FAILURE;

2221

1394

goto end;

2222

1395

}

2223

1396

2230

1403

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

2231

1404

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

2232

1405

or tmpmax != (uint16_t)tmpmax){

2233

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

2234

exitcode = EX_USAGE;

1406

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

1407

exitcode = EXIT_FAILURE;

2235

1408

goto end;

2236

1409

}

2237

1410

2241

1414

2242

1415

port = (uint16_t)tmpmax;

2243

1416

*address = '\0';

1417

address = connect_to;

2244

1418

/* Colon in address indicates IPv6 */

2245

1419

int af;

2246

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

1420

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

2247

1421

af = AF_INET6;

2248

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

2249

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

2250

{

2251

connect_to++;

2252

address[-1] = '\0';

2253

}

2254

1422

} else {

2255

1423

af = AF_INET;

2256

1424

}

2257

address = connect_to;

2258

1425

2259

1426

if(quit_now){

2260

1427

goto end;

2261

1428

}

2262

1429

2263

while(not quit_now){

2264

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

2265

if(quit_now or ret == 0){

2266

break;

2267

}

2268

if(debug){

2269

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

2270

(int)retry_interval);

2271

}

2272

sleep((int)retry_interval);

2273

}

2274

2275

if (not quit_now){

1430

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

1431

if(ret < 0){

1432

exitcode = EXIT_FAILURE;

1433

} else {

2276

1434

exitcode = EXIT_SUCCESS;

2277

1435

}

2278

2279

1436

goto end;

2280

1437

}

2281

1438

2295

1452

/* Allocate a new server */

2296

1453

mc.server = avahi_server_new(avahi_simple_poll_get

2297

1454

(mc.simple_poll), &config, NULL,

2298

NULL, &ret_errno);

1455

NULL, &error);

2299

1456

2300

1457

/* Free the Avahi configuration data */

2301

1458

avahi_server_config_free(&config);

2303

1460

2304

1461

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

2305

1462

if(mc.server == NULL){

2306

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

2307

avahi_strerror(ret_errno));

2308

exitcode = EX_UNAVAILABLE;

1463

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

1464

avahi_strerror(error));

1465

exitcode = EXIT_FAILURE;

2309

1466

goto end;

2310

1467

}

2311

1468

2318

1475

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2319

1476

NULL, 0, browse_callback, NULL);

2320

1477

if(sb == NULL){

2321

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

2322

avahi_strerror(avahi_server_errno(mc.server)));

2323

exitcode = EX_UNAVAILABLE;

1478

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

1479

avahi_strerror(avahi_server_errno(mc.server)));

1480

exitcode = EXIT_FAILURE;

2324

1481

goto end;

2325

1482

}

2326

1483

2331

1488

/* Run the main loop */

2332

1489

2333

1490

if(debug){

2334

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

2335

}

2336

2337

ret = avahi_loop_with_timeout(mc.simple_poll,

2338

(int)(retry_interval * 1000));

2339

if(debug){

2340

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

2341

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

2342

}

1491

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

1492

}

1493

1494

avahi_simple_poll_loop(mc.simple_poll);

2343

1495

2344

1496

end:

2345

1497

2346

1498

if(debug){

2347

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

1499

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

2348

1500

}

2349

1501

2350

1502

/* Cleanup things */

2367

1519

gpgme_release(mc.ctx);

2368

1520

}

2369

1521

2370

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

2371

has seen */

2372

if(mc.current_server != NULL){

2373

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

2374

while(mc.current_server != NULL){

2375

server *next = mc.current_server->next;

2376

free(mc.current_server);

2377

mc.current_server = next;

1522

/* Take down the network interface */

1523

if(take_down_interface){

1524

/* Re-raise priviliges */

1525

errno = 0;

1526

ret = seteuid(0);

1527

if(ret == -1){

1528

perror("seteuid");

2378

1529

}

2379

}

2380

2381

/* Re-raise priviliges */

2382

{

2383

raise_privileges();

2384

2385

/* Run network hooks */

2386

run_network_hooks("stop", interfaces_hooks, delay);

2387

2388

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

2389

{

2390

char *interface = NULL;

2391

while((interface=argz_next(interfaces_to_take_down,

2392

interfaces_to_take_down_size,

2393

interface))){

2394

ret_errno = take_down_interface(interface);

2395

if(ret_errno != 0){

2396

errno = ret_errno;

2397

perror_plus("Failed to take down interface");

1530

if(geteuid() == 0){

1531

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

1532

if(ret == -1){

1533

perror("ioctl SIOCGIFFLAGS");

1534

} else if(network.ifr_flags & IFF_UP) {

1535

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

1536

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

1537

if(ret == -1){

1538

perror("ioctl SIOCSIFFLAGS");

2398

1539

}

2399

1540

}

2400

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

2401

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

2402

" down\n");

1541

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

1542

if(ret == -1){

1543

perror("close");

1544

}

1545

/* Lower privileges permanently */

1546

errno = 0;

1547

ret = setuid(uid);

1548

if(ret == -1){

1549

perror("setuid");

2403

1550

}

2404

1551

}

2405

2406

lower_privileges_permanently();

2407

1552

}

2408

1553

2409

free(interfaces_to_take_down);

2410

free(interfaces_hooks);

2411

2412

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

1554

/* Removes the temp directory used by GPGME */

2413

1555

if(tempdir_created){

2414

struct dirent **direntries = NULL;

2415

struct dirent *direntry = NULL;

2416

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

2417

alphasort);

2418

if (numentries > 0){

2419

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

2420

direntry = direntries[i];

1556

DIR *d;

1557

struct dirent *direntry;

1558

d = opendir(tempdir);

1559

if(d == NULL){

1560

if(errno != ENOENT){

1561

perror("opendir");

1562

}

1563

} else {

1564

while(true){

1565

direntry = readdir(d);

1566

if(direntry == NULL){

1567

break;

1568

}

1569

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

1570

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

1571

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

1572

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

1573

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

1574

continue;

1575

}

2421

1576

char *fullname = NULL;

2422

1577

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

2423

1578

direntry->d_name);

2424

1579

if(ret < 0){

2425

perror_plus("asprintf");

1580

perror("asprintf");

2426

1581

continue;

2427

1582

}

2428

1583

ret = remove(fullname);

2429

1584

if(ret == -1){

2430

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

2431

strerror(errno));

1585

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

1586

strerror(errno));

2432

1587

}

2433

1588

free(fullname);

2434

1589

}

2435

}

2436

2437

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

2438

free(direntries);

2439

if (numentries == -1){

2440

perror_plus("scandir");

1590

closedir(d);

2441

1591

}

2442

1592

ret = rmdir(tempdir);

2443

1593

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

2444

perror_plus("rmdir");

1594

perror("rmdir");

2445

1595

}

2446

1596

}

2447

1597

2448

1598

if(quit_now){

2449

1599

sigemptyset(&old_sigterm_action.sa_mask);

2450

1600

old_sigterm_action.sa_handler = SIG_DFL;

2451

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2452

&old_sigterm_action,

2453

NULL));

1601

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

2454

1602

if(ret == -1){

2455

perror_plus("sigaction");

2456

}

2457

do {

2458

ret = raise(signal_received);

2459

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

2460

if(ret != 0){

2461

perror_plus("raise");

2462

abort();

2463

}

2464

TEMP_FAILURE_RETRY(pause());

1603

perror("sigaction");

1604

}

1605

raise(signal_received);

2465

1606

}

2466

1607

2467

1608

return exitcode;