/mandos/trunk : revision 947

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

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*

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* Everything else is

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*

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

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

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* published by the Free Software Foundation, either version 3 of the

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* License, or (at your option) any later version.

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*

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* This program is distributed in the hope that it will be useful, but

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*

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* This file is part of Mandos.

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*

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* Mandos is free software: you can redistribute it and/or modify it

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* under the terms of the GNU General Public License as published by

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* the Free Software Foundation, either version 3 of the License, or

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* (at your option) any later version.

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*

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* Mandos is distributed in the hope that it will be useful, but

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

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* General Public License for more details.

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*

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* You should have received a copy of the GNU General Public License

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* along with this program. If not, see

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

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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

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*

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

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*/

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

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34

#ifndef _LARGEFILE_SOURCE

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35

#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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

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

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stdout, ferror(), remove() */

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stdout, ferror() */

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

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

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

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48

strtof(), abort() */

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

49

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

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

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

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asprintf(), strncpy(), strsignal()

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*/

51

53

#include <sys/ioctl.h> /* ioctl */

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54

#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

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55

sockaddr_in6, PF_INET6,

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57

opendir(), DIR */

56

58

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

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59

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

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inet_pton(), connect() */

59

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

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

60

63

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

61

64

*/

62

65

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

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66

strtoimax() */

64

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

67

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

65

72

program_invocation_short_name */

66

73

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

67

74

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

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79

*/

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80

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

74

81

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

75

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

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

82

setgid(), pause(), _exit(),

83

unlinkat() */

84

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

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85

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

78

86

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

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87

argp_state, struct argp,

91

99

argz_delete(), argz_append(),

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100

argz_stringify(), argz_add(),

93

101

argz_count() */

102

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

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EAI_SYSTEM, gai_strerror() */

94

104

95

105

#ifdef __linux__

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106

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

138

148

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

139

149

char *connect_to = NULL;

140

150

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

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152

uid_t uid = 65534;

142

153

gid_t gid = 65534;

143

154

180

191

perror(print_text);

181

192

}

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193

183

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

194

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

184

195

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

185

196

va_list ap;

186

197

va_start (ap, format);

195

206

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

196

207

* "buffer_length" is how much is already used.

197

208

*/

209

__attribute__((nonnull, warn_unused_result))

198

210

size_t incbuffer(char **buffer, size_t buffer_length,

199

211

size_t buffer_capacity){

200

212

if(buffer_length + BUFFER_SIZE > buffer_capacity){

201

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

202

if(buffer == NULL){

213

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

214

if(new_buf == NULL){

215

int old_errno = errno;

216

free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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219

return 0;

204

220

}

221

*buffer = new_buf;

205

222

buffer_capacity += BUFFER_SIZE;

206

223

}

207

224

return buffer_capacity;

208

225

}

209

226

210

227

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

228

__attribute__((nonnull, warn_unused_result))

211

229

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

212

230

int af, server **current_server){

213

231

int ret;

222

240

.af = af };

223

241

if(new_server->ip == NULL){

224

242

perror_plus("strdup");

243

free(new_server);

244

return false;

245

}

246

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

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

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

225

258

return false;

226

259

}

227

260

/* Special case of first server */

229

262

new_server->next = new_server;

230

263

new_server->prev = new_server;

231

264

*current_server = new_server;

232

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

233

265

} else {

266

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

234

267

new_server->next = *current_server;

235

268

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

236

269

new_server->prev->next = new_server;

237

270

(*current_server)->prev = new_server;

238

271

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

272

return true;

245

273

}

246

274

247

275

/*

248

276

* Initialize GPGME.

249

277

*/

250

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

251

const char *tempdir, mandos_context *mc){

278

__attribute__((nonnull, warn_unused_result))

279

static bool init_gpgme(const char * const seckey,

280

const char * const pubkey,

281

const char * const tempdir,

282

mandos_context *mc){

252

283

gpgme_error_t rc;

253

284

gpgme_engine_info_t engine_info;

254

285

255

286

/*

256

287

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

257

288

*/

258

bool import_key(const char *filename){

289

bool import_key(const char * const filename){

259

290

int ret;

260

291

int fd;

261

292

gpgme_data_t pgp_data;

279

310

gpgme_strsource(rc), gpgme_strerror(rc));

280

311

return false;

281

312

}

313

{

314

gpgme_import_result_t import_result

315

= gpgme_op_import_result(mc->ctx);

316

if((import_result->imported < 1

317

or import_result->not_imported > 0)

318

and import_result->unchanged == 0){

319

fprintf_plus(stderr, "bad gpgme_op_import_results:\n");

320

fprintf_plus(stderr,

321

"The total number of considered keys: %d\n",

322

import_result->considered);

323

fprintf_plus(stderr,

324

"The number of keys without user ID: %d\n",

325

import_result->no_user_id);

326

fprintf_plus(stderr,

327

"The total number of imported keys: %d\n",

328

import_result->imported);

329

fprintf_plus(stderr, "The number of imported RSA keys: %d\n",

330

import_result->imported_rsa);

331

fprintf_plus(stderr, "The number of unchanged keys: %d\n",

332

import_result->unchanged);

333

fprintf_plus(stderr, "The number of new user IDs: %d\n",

334

import_result->new_user_ids);

335

fprintf_plus(stderr, "The number of new sub keys: %d\n",

336

import_result->new_sub_keys);

337

fprintf_plus(stderr, "The number of new signatures: %d\n",

338

import_result->new_signatures);

339

fprintf_plus(stderr, "The number of new revocations: %d\n",

340

import_result->new_revocations);

341

fprintf_plus(stderr,

342

"The total number of secret keys read: %d\n",

343

import_result->secret_read);

344

fprintf_plus(stderr,

345

"The number of imported secret keys: %d\n",

346

import_result->secret_imported);

347

fprintf_plus(stderr,

348

"The number of unchanged secret keys: %d\n",

349

import_result->secret_unchanged);

350

fprintf_plus(stderr, "The number of keys not imported: %d\n",

351

import_result->not_imported);

352

for(gpgme_import_status_t import_status

353

= import_result->imports;

354

import_status != NULL;

355

import_status = import_status->next){

356

fprintf_plus(stderr, "Import status for key: %s\n",

357

import_status->fpr);

358

if(import_status->result != GPG_ERR_NO_ERROR){

359

fprintf_plus(stderr, "Import result: %s: %s\n",

360

gpgme_strsource(import_status->result),

361

gpgme_strerror(import_status->result));

362

}

363

fprintf_plus(stderr, "Key status:\n");

364

fprintf_plus(stderr,

365

import_status->status & GPGME_IMPORT_NEW

366

? "The key was new.\n"

367

: "The key was not new.\n");

368

fprintf_plus(stderr,

369

import_status->status & GPGME_IMPORT_UID

370

? "The key contained new user IDs.\n"

371

: "The key did not contain new user IDs.\n");

372

fprintf_plus(stderr,

373

import_status->status & GPGME_IMPORT_SIG

374

? "The key contained new signatures.\n"

375

: "The key did not contain new signatures.\n");

376

fprintf_plus(stderr,

377

import_status->status & GPGME_IMPORT_SUBKEY

378

? "The key contained new sub keys.\n"

379

: "The key did not contain new sub keys.\n");

380

fprintf_plus(stderr,

381

import_status->status & GPGME_IMPORT_SECRET

382

? "The key contained a secret key.\n"

383

: "The key did not contain a secret key.\n");

384

}

385

return false;

386

}

387

}

282

388

283

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

389

ret = close(fd);

284

390

if(ret == -1){

285

391

perror_plus("close");

286

392

}

325

431

/* Create new GPGME "context" */

326

432

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

327

433

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));

434

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

435

gpgme_strsource(rc), gpgme_strerror(rc));

331

436

return false;

332

437

}

333

438

342

447

* Decrypt OpenPGP data.

343

448

* Returns -1 on error

344

449

*/

450

__attribute__((nonnull, warn_unused_result))

345

451

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

452

size_t crypto_size,

347

453

char **plaintext,

368

474

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

369

475

rc = gpgme_data_new(&dh_plain);

370

476

if(rc != GPG_ERR_NO_ERROR){

371

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

372

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

477

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

373

478

gpgme_strsource(rc), gpgme_strerror(rc));

374

479

gpgme_data_release(dh_crypto);

375

480

return -1;

388

493

if(result == NULL){

389

494

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

390

495

} 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);

496

if(result->unsupported_algorithm != NULL) {

497

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

498

result->unsupported_algorithm);

499

}

500

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

501

result->wrong_key_usage ? "Yes" : "No");

395

502

if(result->file_name != NULL){

396

503

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

397

504

}

467

574

return plaintext_length;

468

575

}

469

576

470

static const char * safer_gnutls_strerror(int value){

577

__attribute__((warn_unused_result, const))

578

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

579

if(str == NULL)

580

return "(unknown)";

581

return str;

582

}

583

584

__attribute__((warn_unused_result))

585

static const char *safer_gnutls_strerror(int value){

471

586

const char *ret = gnutls_strerror(value);

472

if(ret == NULL)

473

ret = "(unknown)";

474

return ret;

587

return safe_string(ret);

475

588

}

476

589

477

590

/* GnuTLS log function callback */

591

__attribute__((nonnull))

478

592

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

479

593

const char* string){

480

594

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

481

595

}

482

596

597

__attribute__((nonnull(1, 2, 4), warn_unused_result))

483

598

static int init_gnutls_global(const char *pubkeyfilename,

484

599

const char *seckeyfilename,

600

const char *dhparamsfilename,

485

601

mandos_context *mc){

486

602

int ret;

603

unsigned int uret;

487

604

488

605

if(debug){

489

606

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

490

607

}

491

608

492

ret = gnutls_global_init();

493

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

496

return -1;

497

}

498

499

609

if(debug){

500

610

/* "Use a log level over 10 to enable all debugging options."

501

611

* - GnuTLS manual

509

619

if(ret != GNUTLS_E_SUCCESS){

510

620

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

511

621

safer_gnutls_strerror(ret));

512

gnutls_global_deinit();

513

622

return -1;

514

623

}

515

624

540

649

safer_gnutls_strerror(ret));

541

650

goto globalfail;

542

651

}

543

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

544

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

547

goto globalfail;

548

}

549

652

/* If a Diffie-Hellman parameters file was given, try to use it */

653

if(dhparamsfilename != NULL){

654

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

655

do {

656

int dhpfile = open(dhparamsfilename, O_RDONLY);

657

if(dhpfile == -1){

658

perror_plus("open");

659

dhparamsfilename = NULL;

660

break;

661

}

662

size_t params_capacity = 0;

663

while(true){

664

params_capacity = incbuffer((char **)&params.data,

665

(size_t)params.size,

666

(size_t)params_capacity);

667

if(params_capacity == 0){

668

perror_plus("incbuffer");

669

free(params.data);

670

params.data = NULL;

671

dhparamsfilename = NULL;

672

break;

673

}

674

ssize_t bytes_read = read(dhpfile,

675

params.data + params.size,

676

BUFFER_SIZE);

677

/* EOF */

678

if(bytes_read == 0){

679

break;

680

}

681

/* check bytes_read for failure */

682

if(bytes_read < 0){

683

perror_plus("read");

684

free(params.data);

685

params.data = NULL;

686

dhparamsfilename = NULL;

687

break;

688

}

689

params.size += (unsigned int)bytes_read;

690

}

691

ret = close(dhpfile);

692

if(ret == -1){

693

perror_plus("close");

694

}

695

if(params.data == NULL){

696

dhparamsfilename = NULL;

697

}

698

if(dhparamsfilename == NULL){

699

break;

700

}

701

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

702

GNUTLS_X509_FMT_PEM);

703

if(ret != GNUTLS_E_SUCCESS){

704

fprintf_plus(stderr, "Failed to parse DH parameters in file"

705

" \"%s\": %s\n", dhparamsfilename,

706

safer_gnutls_strerror(ret));

707

dhparamsfilename = NULL;

708

}

709

free(params.data);

710

} while(false);

711

}

712

if(dhparamsfilename == NULL){

713

if(mc->dh_bits == 0){

714

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

715

/* Try to read the private key file */

716

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

717

do {

718

int secfile = open(seckeyfilename, O_RDONLY);

719

if(secfile == -1){

720

perror_plus("open");

721

break;

722

}

723

size_t buffer_capacity = 0;

724

while(true){

725

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

726

(size_t)buffer.size,

727

(size_t)buffer_capacity);

728

if(buffer_capacity == 0){

729

perror_plus("incbuffer");

730

free(buffer.data);

731

buffer.data = NULL;

732

break;

733

}

734

ssize_t bytes_read = read(secfile,

735

buffer.data + buffer.size,

736

BUFFER_SIZE);

737

/* EOF */

738

if(bytes_read == 0){

739

break;

740

}

741

/* check bytes_read for failure */

742

if(bytes_read < 0){

743

perror_plus("read");

744

free(buffer.data);

745

buffer.data = NULL;

746

break;

747

}

748

buffer.size += (unsigned int)bytes_read;

749

}

750

close(secfile);

751

} while(false);

752

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

753

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

754

if(buffer.data != NULL){

755

{

756

gnutls_openpgp_privkey_t privkey = NULL;

757

ret = gnutls_openpgp_privkey_init(&privkey);

758

if(ret != GNUTLS_E_SUCCESS){

759

fprintf_plus(stderr, "Error initializing OpenPGP key"

760

" structure: %s",

761

safer_gnutls_strerror(ret));

762

free(buffer.data);

763

buffer.data = NULL;

764

} else {

765

ret = gnutls_openpgp_privkey_import

766

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

767

if(ret != GNUTLS_E_SUCCESS){

768

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

769

safer_gnutls_strerror(ret));

770

privkey = NULL;

771

}

772

free(buffer.data);

773

buffer.data = NULL;

774

if(privkey != NULL){

775

/* Use private key to suggest an appropriate

776

sec_param */

777

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

778

gnutls_openpgp_privkey_deinit(privkey);

779

if(debug){

780

fprintf_plus(stderr, "This OpenPGP key implies using"

781

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

782

safe_string(gnutls_sec_param_get_name

783

(sec_param)));

784

}

785

}

786

}

787

}

788

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

789

/* Err on the side of caution */

790

sec_param = GNUTLS_SEC_PARAM_ULTRA;

791

if(debug){

792

fprintf_plus(stderr, "Falling back to security parameter"

793

" \"%s\"\n",

794

safe_string(gnutls_sec_param_get_name

795

(sec_param)));

796

}

797

}

798

}

799

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

800

if(uret != 0){

801

mc->dh_bits = uret;

802

if(debug){

803

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

804

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

805

safe_string(gnutls_sec_param_get_name

806

(sec_param)),

807

mc->dh_bits);

808

}

809

} else {

810

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

811

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

812

safe_string(gnutls_sec_param_get_name

813

(sec_param)),

814

safer_gnutls_strerror(ret));

815

goto globalfail;

816

}

817

} else if(debug){

818

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

819

mc->dh_bits);

820

}

821

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

822

if(ret != GNUTLS_E_SUCCESS){

823

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

824

" bits): %s\n", mc->dh_bits,

825

safer_gnutls_strerror(ret));

826

goto globalfail;

827

}

828

}

550

829

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

551

830

552

831

return 0;

554

833

globalfail:

555

834

556

835

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_global_deinit();

558

836

gnutls_dh_params_deinit(mc->dh_params);

559

837

return -1;

560

838

}

561

839

840

__attribute__((nonnull, warn_unused_result))

562

841

static int init_gnutls_session(gnutls_session_t *session,

563

842

mandos_context *mc){

564

843

int ret;

611

890

/* ignore client certificate if any. */

612

891

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

892

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

615

616

893

return 0;

617

894

}

618

895

620

897

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

621

898

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

622

899

900

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

901

__attribute__((warn_unused_result))

902

int raise_privileges(void){

903

int old_errno = errno;

904

int ret = 0;

905

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

906

ret = errno;

907

}

908

errno = old_errno;

909

return ret;

910

}

911

912

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

913

__attribute__((warn_unused_result))

914

int raise_privileges_permanently(void){

915

int old_errno = errno;

916

int ret = raise_privileges();

917

if(ret != 0){

918

errno = old_errno;

919

return ret;

920

}

921

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

922

ret = errno;

923

}

924

errno = old_errno;

925

return ret;

926

}

927

928

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

929

__attribute__((warn_unused_result))

930

int lower_privileges(void){

931

int old_errno = errno;

932

int ret = 0;

933

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

934

ret = errno;

935

}

936

errno = old_errno;

937

return ret;

938

}

939

940

/* Lower privileges permanently */

941

__attribute__((warn_unused_result))

942

int lower_privileges_permanently(void){

943

int old_errno = errno;

944

int ret = 0;

945

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

946

ret = errno;

947

}

948

errno = old_errno;

949

return ret;

950

}

951

952

/* Helper function to add_local_route() and delete_local_route() */

953

__attribute__((nonnull, warn_unused_result))

954

static bool add_delete_local_route(const bool add,

955

const char *address,

956

AvahiIfIndex if_index){

957

int ret;

958

char helper[] = "mandos-client-iprouteadddel";

959

char add_arg[] = "add";

960

char delete_arg[] = "delete";

961

char debug_flag[] = "--debug";

962

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

963

if(pluginhelperdir == NULL){

964

if(debug){

965

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

966

" variable not set; cannot run helper\n");

967

}

968

return false;

969

}

970

971

char interface[IF_NAMESIZE];

972

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

973

perror_plus("if_indextoname");

974

return false;

975

}

976

977

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

978

if(devnull == -1){

979

perror_plus("open(\"/dev/null\", O_RDONLY)");

980

return false;

981

}

982

pid_t pid = fork();

983

if(pid == 0){

984

/* Child */

985

/* Raise privileges */

986

errno = raise_privileges_permanently();

987

if(errno != 0){

988

perror_plus("Failed to raise privileges");

989

/* _exit(EX_NOPERM); */

990

} else {

991

/* Set group */

992

errno = 0;

993

ret = setgid(0);

994

if(ret == -1){

995

perror_plus("setgid");

996

_exit(EX_NOPERM);

997

}

998

/* Reset supplementary groups */

999

errno = 0;

1000

ret = setgroups(0, NULL);

1001

if(ret == -1){

1002

perror_plus("setgroups");

1003

_exit(EX_NOPERM);

1004

}

1005

}

1006

ret = dup2(devnull, STDIN_FILENO);

1007

if(ret == -1){

1008

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

1009

_exit(EX_OSERR);

1010

}

1011

ret = close(devnull);

1012

if(ret == -1){

1013

perror_plus("close");

1014

_exit(EX_OSERR);

1015

}

1016

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1017

if(ret == -1){

1018

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

1019

_exit(EX_OSERR);

1020

}

1021

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

1022

O_RDONLY

1023

| O_DIRECTORY

1024

| O_PATH

1025

| O_CLOEXEC));

1026

if(helperdir_fd == -1){

1027

perror_plus("open");

1028

_exit(EX_UNAVAILABLE);

1029

}

1030

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

1031

helper, O_RDONLY));

1032

if(helper_fd == -1){

1033

perror_plus("openat");

1034

close(helperdir_fd);

1035

_exit(EX_UNAVAILABLE);

1036

}

1037

close(helperdir_fd);

1038

#ifdef __GNUC__

1039

#pragma GCC diagnostic push

1040

#pragma GCC diagnostic ignored "-Wcast-qual"

1041

#endif

1042

if(fexecve(helper_fd, (char *const [])

1043

{ helper, add ? add_arg : delete_arg, (char *)address,

1044

interface, debug ? debug_flag : NULL, NULL },

1045

environ) == -1){

1046

#ifdef __GNUC__

1047

#pragma GCC diagnostic pop

1048

#endif

1049

perror_plus("fexecve");

1050

_exit(EXIT_FAILURE);

1051

}

1052

}

1053

if(pid == -1){

1054

perror_plus("fork");

1055

return false;

1056

}

1057

int status;

1058

pid_t pret = -1;

1059

errno = 0;

1060

do {

1061

pret = waitpid(pid, &status, 0);

1062

if(pret == -1 and errno == EINTR and quit_now){

1063

int errno_raising = 0;

1064

if((errno = raise_privileges()) != 0){

1065

errno_raising = errno;

1066

perror_plus("Failed to raise privileges in order to"

1067

" kill helper program");

1068

}

1069

if(kill(pid, SIGTERM) == -1){

1070

perror_plus("kill");

1071

}

1072

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

1073

perror_plus("Failed to lower privileges after killing"

1074

" helper program");

1075

}

1076

return false;

1077

}

1078

} while(pret == -1 and errno == EINTR);

1079

if(pret == -1){

1080

perror_plus("waitpid");

1081

return false;

1082

}

1083

if(WIFEXITED(status)){

1084

if(WEXITSTATUS(status) != 0){

1085

fprintf_plus(stderr, "Error: iprouteadddel exited"

1086

" with status %d\n", WEXITSTATUS(status));

1087

return false;

1088

}

1089

return true;

1090

}

1091

if(WIFSIGNALED(status)){

1092

fprintf_plus(stderr, "Error: iprouteadddel died by"

1093

" signal %d\n", WTERMSIG(status));

1094

return false;

1095

}

1096

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

1097

return false;

1098

}

1099

1100

__attribute__((nonnull, warn_unused_result))

1101

static bool add_local_route(const char *address,

1102

AvahiIfIndex if_index){

1103

if(debug){

1104

fprintf_plus(stderr, "Adding route to %s\n", address);

1105

}

1106

return add_delete_local_route(true, address, if_index);

1107

}

1108

1109

__attribute__((nonnull, warn_unused_result))

1110

static bool delete_local_route(const char *address,

1111

AvahiIfIndex if_index){

1112

if(debug){

1113

fprintf_plus(stderr, "Removing route to %s\n", address);

1114

}

1115

return add_delete_local_route(false, address, if_index);

1116

}

1117

623

1118

/* Called when a Mandos server is found */

1119

__attribute__((nonnull, warn_unused_result))

624

1120

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

625

1121

AvahiIfIndex if_index,

626

1122

int af, mandos_context *mc){

627

1123

int ret, tcp_sd = -1;

628

1124

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1125

struct sockaddr_storage to;

633

1126

char *buffer = NULL;

634

1127

char *decrypted_buffer = NULL;

635

1128

size_t buffer_length = 0;

638

1131

int retval = -1;

639

1132

gnutls_session_t session;

640

1133

int pf; /* Protocol family */

1134

bool route_added = false;

641

1135

642

1136

errno = 0;

643

1137

665

1159

bool match = false;

666

1160

{

667

1161

char *interface = NULL;

668

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

669

interface))){

1162

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

1163

mc->interfaces_size,

1164

interface))){

670

1165

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

671

1166

match = true;

672

1167

break;

701

1196

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

702

1197

}

703

1198

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

1199

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

705

1200

if(tcp_sd < 0){

706

1201

int e = errno;

707

1202

perror_plus("socket");

714

1209

goto mandos_end;

715

1210

}

716

1211

717

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

718

1212

if(af == AF_INET6){

719

to.in6.sin6_family = (sa_family_t)af;

720

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

1213

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1214

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1215

ret = inet_pton(af, ip, &to6->sin6_addr);

721

1216

} else { /* IPv4 */

722

to.in.sin_family = (sa_family_t)af;

723

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

1217

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1218

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1219

ret = inet_pton(af, ip, &to4->sin_addr);

724

1220

}

725

1221

if(ret < 0 ){

726

1222

int e = errno;

735

1231

goto mandos_end;

736

1232

}

737

1233

if(af == AF_INET6){

738

to.in6.sin6_port = htons(port);

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

740

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

741

-Wunreachable-code*/

1234

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

1235

if(IN6_IS_ADDR_LINKLOCAL

1236

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

742

1237

if(if_index == AVAHI_IF_UNSPEC){

743

1238

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

744

1239

" incomplete without a network interface\n");

746

1241

goto mandos_end;

747

1242

}

748

1243

/* Set the network interface number as scope */

749

to.in6.sin6_scope_id = (uint32_t)if_index;

1244

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

750

1245

}

751

1246

} else {

752

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

753

-Wconversion and

754

-Wunreachable-code */

1247

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

755

1248

}

756

1249

757

1250

if(quit_now){

774

1267

}

775

1268

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

776

1269

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

777

const char *pcret;

778

if(af == AF_INET6){

779

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

780

sizeof(addrstr));

781

} else {

782

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

783

sizeof(addrstr));

784

}

785

if(pcret == NULL){

786

perror_plus("inet_ntop");

787

} else {

788

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

789

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

790

}

791

}

792

}

793

794

if(quit_now){

795

errno = EINTR;

796

goto mandos_end;

797

}

798

799

if(af == AF_INET6){

800

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

801

} else {

802

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

803

}

804

if(ret < 0){

805

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

806

int e = errno;

807

perror_plus("connect");

808

errno = e;

809

}

810

goto mandos_end;

811

}

812

813

if(quit_now){

814

errno = EINTR;

815

goto mandos_end;

1270

if(af == AF_INET6){

1271

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

1272

sizeof(struct sockaddr_in6),

1273

addrstr, sizeof(addrstr), NULL, 0,

1274

NI_NUMERICHOST);

1275

} else {

1276

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

1277

sizeof(struct sockaddr_in),

1278

addrstr, sizeof(addrstr), NULL, 0,

1279

NI_NUMERICHOST);

1280

}

1281

if(ret == EAI_SYSTEM){

1282

perror_plus("getnameinfo");

1283

} else if(ret != 0) {

1284

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

1285

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

1286

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

1287

}

1288

}

1289

1290

if(quit_now){

1291

errno = EINTR;

1292

goto mandos_end;

1293

}

1294

1295

while(true){

1296

if(af == AF_INET6){

1297

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

1298

sizeof(struct sockaddr_in6));

1299

} else {

1300

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

1301

sizeof(struct sockaddr_in));

1302

}

1303

if(ret < 0){

1304

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1305

and if_index != AVAHI_IF_UNSPEC

1306

and connect_to == NULL

1307

and not route_added and

1308

((af == AF_INET6 and not

1309

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1310

&to)->sin6_addr)))

1311

or (af == AF_INET and

1312

/* Not a a IPv4LL address */

1313

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1314

& 0xFFFF0000L) != 0xA9FE0000L))){

1315

/* Work around Avahi bug - Avahi does not announce link-local

1316

addresses if it has a global address, so local hosts with

1317

*only* a link-local address (e.g. Mandos clients) cannot

1318

connect to a Mandos server announced by Avahi on a server

1319

host with a global address. Work around this by retrying

1320

with an explicit route added with the server's address.

1321

1322

Avahi bug reference:

1323

https://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1324

https://bugs.debian.org/587961

1325

*/

1326

if(debug){

1327

fprintf_plus(stderr, "Mandos server unreachable, trying"

1328

" direct route\n");

1329

}

1330

int e = errno;

1331

route_added = add_local_route(ip, if_index);

1332

if(route_added){

1333

continue;

1334

}

1335

errno = e;

1336

}

1337

if(errno != ECONNREFUSED or debug){

1338

int e = errno;

1339

perror_plus("connect");

1340

errno = e;

1341

}

1342

goto mandos_end;

1343

}

1344

1345

if(quit_now){

1346

errno = EINTR;

1347

goto mandos_end;

1348

}

1349

break;

816

1350

}

817

1351

818

1352

const char *out = mandos_protocol_version;

972

1506

&decrypted_buffer, mc);

973

1507

if(decrypted_buffer_size >= 0){

974

1508

1509

clearerr(stdout);

975

1510

written = 0;

976

1511

while(written < (size_t) decrypted_buffer_size){

977

1512

if(quit_now){

993

1528

}

994

1529

written += (size_t)ret;

995

1530

}

1531

ret = fflush(stdout);

1532

if(ret != 0){

1533

int e = errno;

1534

if(debug){

1535

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

1536

strerror(errno));

1537

}

1538

errno = e;

1539

goto mandos_end;

1540

}

996

1541

retval = 0;

997

1542

}

998

1543

}

1001

1546

1002

1547

mandos_end:

1003

1548

{

1549

if(route_added){

1550

if(not delete_local_route(ip, if_index)){

1551

fprintf_plus(stderr, "Failed to delete local route to %s on"

1552

" interface %d", ip, if_index);

1553

}

1554

}

1004

1555

int e = errno;

1005

1556

free(decrypted_buffer);

1006

1557

free(buffer);

1007

1558

if(tcp_sd >= 0){

1008

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

1559

ret = close(tcp_sd);

1009

1560

}

1010

1561

if(ret == -1){

1011

1562

if(e == 0){

1036

1587

AVAHI_GCC_UNUSED AvahiStringList *txt,

1037

1588

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1038

1589

flags,

1039

void* mc){

1590

void *mc){

1040

1591

if(r == NULL){

1041

1592

return;

1042

1593

}

1045

1596

timed out */

1046

1597

1047

1598

if(quit_now){

1599

avahi_s_service_resolver_free(r);

1048

1600

return;

1049

1601

}

1050

1602

1095

1647

const char *domain,

1096

1648

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1097

1649

flags,

1098

void* mc){

1650

void *mc){

1099

1651

if(b == NULL){

1100

1652

return;

1101

1653

}

1161

1713

errno = old_errno;

1162

1714

}

1163

1715

1716

__attribute__((nonnull, warn_unused_result))

1164

1717

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

1165

1718

int ret;

1166

error_t ret_errno;

1719

int old_errno;

1167

1720

1168

1721

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

1169

1722

if(s < 0){

1170

ret_errno = errno;

1723

old_errno = errno;

1171

1724

perror_plus("socket");

1172

errno = ret_errno;

1725

errno = old_errno;

1173

1726

return false;

1174

1727

}

1175

strcpy(ifr->ifr_name, ifname);

1728

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1729

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1176

1730

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1177

1731

if(ret == -1){

1178

1732

if(debug){

1179

ret_errno = errno;

1733

old_errno = errno;

1180

1734

perror_plus("ioctl SIOCGIFFLAGS");

1181

errno = ret_errno;

1735

errno = old_errno;

1736

}

1737

if((close(s) == -1) and debug){

1738

old_errno = errno;

1739

perror_plus("close");

1740

errno = old_errno;

1182

1741

}

1183

1742

return false;

1184

1743

}

1744

if((close(s) == -1) and debug){

1745

old_errno = errno;

1746

perror_plus("close");

1747

errno = old_errno;

1748

}

1185

1749

return true;

1186

1750

}

1187

1751

1752

__attribute__((nonnull, warn_unused_result))

1188

1753

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

1189

1754

1190

1755

/* Reject the loopback device */

1232

1797

* corresponds to an acceptable network device.

1233

1798

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

1234

1799

*/

1800

__attribute__((nonnull, warn_unused_result))

1235

1801

int good_interface(const struct dirent *if_entry){

1236

1802

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

1237

1803

return 0;

1255

1821

/*

1256

1822

* This function determines if a network interface is up.

1257

1823

*/

1824

__attribute__((nonnull, warn_unused_result))

1258

1825

bool interface_is_up(const char *interface){

1259

1826

struct ifreq ifr;

1260

1827

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

1271

1838

/*

1272

1839

* This function determines if a network interface is running

1273

1840

*/

1841

__attribute__((nonnull, warn_unused_result))

1274

1842

bool interface_is_running(const char *interface){

1275

1843

struct ifreq ifr;

1276

1844

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

1284

1852

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

1285

1853

}

1286

1854

1855

__attribute__((nonnull, pure, warn_unused_result))

1287

1856

int notdotentries(const struct dirent *direntry){

1288

1857

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

1289

1858

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

1296

1865

}

1297

1866

1298

1867

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

1868

__attribute__((nonnull, warn_unused_result))

1299

1869

int runnable_hook(const struct dirent *direntry){

1300

1870

int ret;

1301

1871

size_t sret;

1309

1879

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

1310

1880

"abcdefghijklmnopqrstuvwxyz"

1311

1881

"0123456789"

1312

"_-");

1882

"_.-");

1313

1883

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

1314

1884

/* Contains non-allowed characters */

1315

1885

if(debug){

1319

1889

return 0;

1320

1890

}

1321

1891

1322

char *fullname = NULL;

1323

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

1324

if(ret < 0){

1325

perror_plus("asprintf");

1326

return 0;

1327

}

1328

1329

ret = stat(fullname, &st);

1892

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

1330

1893

if(ret == -1){

1331

1894

if(debug){

1332

1895

perror_plus("Could not stat hook");

1356

1919

return 1;

1357

1920

}

1358

1921

1922

__attribute__((nonnull, warn_unused_result))

1359

1923

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

1924

mandos_context *mc){

1361

1925

int ret;

1365

1929

1366

1930

while(true){

1367

1931

if(mc->current_server == NULL){

1368

if (debug){

1932

if(debug){

1369

1933

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

1370

1934

" No timeout!\n");

1371

1935

}

1372

1936

ret = avahi_simple_poll_iterate(s, -1);

1373

1937

} else {

1374

if (debug){

1938

if(debug){

1375

1939

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

1376

1940

" it, or wait\n");

1377

1941

}

1394

1958

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

1395

1959

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

1396

1960

1397

if (debug){

1961

if(debug){

1398

1962

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

1399

1963

block_time);

1400

1964

}

1422

1986

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

1423

1987

}

1424

1988

if(ret != 0){

1425

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

1989

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

1426

1990

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

1427

1991

}

1428

1992

}

1429

1993

}

1430

1994

}

1431

1995

1432

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

1433

error_t raise_privileges(void){

1434

error_t old_errno = errno;

1435

error_t ret_errno = 0;

1436

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

1437

ret_errno = errno;

1438

perror_plus("seteuid");

1439

}

1440

errno = old_errno;

1441

return ret_errno;

1442

}

1443

1444

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

1445

error_t raise_privileges_permanently(void){

1446

error_t old_errno = errno;

1447

error_t ret_errno = raise_privileges();

1448

if(ret_errno != 0){

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

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

1453

ret_errno = errno;

1454

perror_plus("seteuid");

1455

}

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

1460

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

1461

error_t lower_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

/* Lower privileges permanently */

1473

error_t lower_privileges_permanently(void){

1474

error_t old_errno = errno;

1475

error_t ret_errno = 0;

1476

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

1477

ret_errno = errno;

1478

perror_plus("setuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1996

__attribute__((nonnull))

1997

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

1485

1998

const float delay){

1486

struct dirent **direntries;

1999

struct dirent **direntries = NULL;

2000

if(hookdir_fd == -1){

2001

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2002

| O_CLOEXEC);

2003

if(hookdir_fd == -1){

2004

if(errno == ENOENT){

2005

if(debug){

2006

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

2007

" found\n", hookdir);

2008

}

2009

} else {

2010

perror_plus("open");

2011

}

2012

return;

2013

}

2014

}

2015

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

2016

if(devnull == -1){

2017

perror_plus("open(\"/dev/null\", O_RDONLY)");

2018

return;

2019

}

2020

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

2021

runnable_hook, alphasort);

2022

if(numhooks == -1){

2023

perror_plus("scandir");

2024

close(devnull);

2025

return;

2026

}

1487

2027

struct dirent *direntry;

1488

2028

int ret;

1489

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

1490

alphasort);

1491

if(numhooks == -1){

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

2029

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

2030

direntry = direntries[i];

2031

if(debug){

2032

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

2033

direntry->d_name);

1499

2034

}

1500

} else {

1501

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

1502

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

1503

direntry = direntries[i];

1504

char *fullname = NULL;

1505

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

1506

if(ret < 0){

2035

pid_t hook_pid = fork();

2036

if(hook_pid == 0){

2037

/* Child */

2038

/* Raise privileges */

2039

errno = raise_privileges_permanently();

2040

if(errno != 0){

2041

perror_plus("Failed to raise privileges");

2042

_exit(EX_NOPERM);

2043

}

2044

/* Set group */

2045

errno = 0;

2046

ret = setgid(0);

2047

if(ret == -1){

2048

perror_plus("setgid");

2049

_exit(EX_NOPERM);

2050

}

2051

/* Reset supplementary groups */

2052

errno = 0;

2053

ret = setgroups(0, NULL);

2054

if(ret == -1){

2055

perror_plus("setgroups");

2056

_exit(EX_NOPERM);

2057

}

2058

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

2059

if(ret == -1){

2060

perror_plus("setenv");

2061

_exit(EX_OSERR);

2062

}

2063

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

2064

if(ret == -1){

2065

perror_plus("setenv");

2066

_exit(EX_OSERR);

2067

}

2068

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

2069

if(ret == -1){

2070

perror_plus("setenv");

2071

_exit(EX_OSERR);

2072

}

2073

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

2074

if(ret == -1){

2075

perror_plus("setenv");

2076

_exit(EX_OSERR);

2077

}

2078

char *delaystring;

2079

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

2080

if(ret == -1){

1507

2081

perror_plus("asprintf");

1508

continue;

1509

}

1510

if(debug){

1511

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

1512

direntry->d_name);

1513

}

1514

pid_t hook_pid = fork();

1515

if(hook_pid == 0){

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1531

dup2(devnull, STDIN_FILENO);

1532

close(devnull);

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

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

1540

if(ret == -1){

1541

perror_plus("setenv");

1542

_exit(EX_OSERR);

1543

}

1544

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

1545

if(ret == -1){

1546

perror_plus("setenv");

1547

_exit(EX_OSERR);

1548

}

1549

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

1550

if(ret == -1){

1551

perror_plus("setenv");

1552

_exit(EX_OSERR);

1553

}

1554

char *delaystring;

1555

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

1556

if(ret == -1){

1557

perror_plus("asprintf");

1558

_exit(EX_OSERR);

1559

}

1560

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

1561

if(ret == -1){

1562

free(delaystring);

1563

perror_plus("setenv");

1564

_exit(EX_OSERR);

1565

}

2082

_exit(EX_OSERR);

2083

}

2084

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

2085

if(ret == -1){

1566

2086

free(delaystring);

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

2087

perror_plus("setenv");

2088

_exit(EX_OSERR);

2089

}

2090

free(delaystring);

2091

if(connect_to != NULL){

2092

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

2093

if(ret == -1){

2094

perror_plus("setenv");

2095

_exit(EX_OSERR);

2096

}

2097

}

2098

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

2099

direntry->d_name,

2100

O_RDONLY));

2101

if(hook_fd == -1){

2102

perror_plus("openat");

2103

_exit(EXIT_FAILURE);

2104

}

2105

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

2106

perror_plus("close");

2107

_exit(EXIT_FAILURE);

2108

}

2109

ret = dup2(devnull, STDIN_FILENO);

2110

if(ret == -1){

2111

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

2112

_exit(EX_OSERR);

2113

}

2114

ret = close(devnull);

2115

if(ret == -1){

2116

perror_plus("close");

2117

_exit(EX_OSERR);

2118

}

2119

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2120

if(ret == -1){

2121

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

2122

_exit(EX_OSERR);

2123

}

2124

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

2125

environ) == -1){

2126

perror_plus("fexecve");

2127

_exit(EXIT_FAILURE);

2128

}

2129

} else {

2130

if(hook_pid == -1){

2131

perror_plus("fork");

2132

free(direntry);

2133

continue;

2134

}

2135

int status;

2136

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

2137

perror_plus("waitpid");

2138

free(direntry);

2139

continue;

2140

}

2141

if(WIFEXITED(status)){

2142

if(WEXITSTATUS(status) != 0){

2143

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

2144

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

2145

WEXITSTATUS(status));

2146

free(direntry);

2147

continue;

2148

}

2149

} else if(WIFSIGNALED(status)){

2150

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

2151

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

2152

WTERMSIG(status));

2153

free(direntry);

2154

continue;

1578

2155

} else {

1579

int status;

1580

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

1581

perror_plus("waitpid");

1582

free(fullname);

1583

continue;

1584

}

1585

if(WIFEXITED(status)){

1586

if(WEXITSTATUS(status) != 0){

1587

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

1588

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

1589

WEXITSTATUS(status));

1590

free(fullname);

1591

continue;

1592

}

1593

} else if(WIFSIGNALED(status)){

1594

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

1595

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

1596

WTERMSIG(status));

1597

free(fullname);

1598

continue;

1599

} else {

1600

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

1601

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

1602

free(fullname);

1603

continue;

1604

}

1605

}

1606

free(fullname);

1607

if(debug){

1608

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

1609

direntry->d_name);

1610

}

1611

}

1612

close(devnull);

1613

}

1614

return true;

2156

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

2157

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

2158

free(direntry);

2159

continue;

2160

}

2161

}

2162

if(debug){

2163

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

2164

direntry->d_name);

2165

}

2166

free(direntry);

2167

}

2168

free(direntries);

2169

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

2170

perror_plus("close");

2171

} else {

2172

hookdir_fd = -1;

2173

}

2174

close(devnull);

1615

2175

}

1616

2176

1617

error_t bring_up_interface(const char *const interface,

1618

const float delay){

1619

int sd = -1;

1620

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

2177

__attribute__((nonnull, warn_unused_result))

2178

int bring_up_interface(const char *const interface,

2179

const float delay){

2180

int old_errno = errno;

2181

int ret;

1623

2182

struct ifreq network;

1624

2183

unsigned int if_index = if_nametoindex(interface);

1625

2184

if(if_index == 0){

1634

2193

}

1635

2194

1636

2195

if(not interface_is_up(interface)){

1637

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

2196

int ret_errno = 0;

2197

int ioctl_errno = 0;

2198

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

1638

2199

ret_errno = errno;

1639

2200

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

1640

2201

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

2202

errno = old_errno;

1641

2203

return ret_errno;

1642

2204

}

1643

network.ifr_flags |= IFF_UP;

2205

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

1644

2206

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

2207

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

2208

if(sd == -1){

1647

2209

ret_errno = errno;

1648

2210

perror_plus("socket");

1649

2211

errno = old_errno;

1650

2212

return ret_errno;

1651

2213

}

1652

2214

1653

2215

if(quit_now){

1654

close(sd);

2216

ret = close(sd);

2217

if(ret == -1){

2218

perror_plus("close");

2219

}

1655

2220

errno = old_errno;

1656

2221

return EINTR;

1657

2222

}

1661

2226

interface);

1662

2227

}

1663

2228

1664

/* Raise priviliges */

1665

raise_privileges();

2229

/* Raise privileges */

2230

ret_errno = raise_privileges();

2231

if(ret_errno != 0){

2232

errno = ret_errno;

2233

perror_plus("Failed to raise privileges");

2234

}

1666

2235

1667

2236

#ifdef __linux__

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

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

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

2237

int ret_linux;

2238

bool restore_loglevel = false;

2239

if(ret_errno == 0){

2240

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2241

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

2242

ret_linux = klogctl(8, NULL, 5);

2243

if(ret_linux == -1){

2244

perror_plus("klogctl");

2245

} else {

2246

restore_loglevel = true;

2247

}

1675

2248

}

1676

2249

#endif /* __linux__ */

1677

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

1678

ret_errno = errno;

2250

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

2251

ioctl_errno = errno;

1679

2252

#ifdef __linux__

1680

2253

if(restore_loglevel){

1681

2254

ret_linux = klogctl(7, NULL, 0);

1685

2258

}

1686

2259

#endif /* __linux__ */

1687

2260

1688

/* Lower privileges */

1689

lower_privileges();

2261

/* If raise_privileges() succeeded above */

2262

if(ret_errno == 0){

2263

/* Lower privileges */

2264

ret_errno = lower_privileges();

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2267

perror_plus("Failed to lower privileges");

2268

}

2269

}

1690

2270

1691

2271

/* Close the socket */

1692

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

2272

ret = close(sd);

1693

2273

if(ret == -1){

1694

2274

perror_plus("close");

1695

2275

}

1696

2276

1697

2277

if(ret_setflags == -1){

1698

errno = ret_errno;

2278

errno = ioctl_errno;

1699

2279

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1700

2280

errno = old_errno;

1701

return ret_errno;

2281

return ioctl_errno;

1702

2282

}

1703

2283

} else if(debug){

1704

2284

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

1707

2287

1708

2288

/* Sleep checking until interface is running.

1709

2289

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

1710

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

2290

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

1711

2291

if(interface_is_running(interface)){

1712

2292

break;

1713

2293

}

1722

2302

return 0;

1723

2303

}

1724

2304

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

2305

__attribute__((nonnull, warn_unused_result))

2306

int take_down_interface(const char *const interface){

2307

int old_errno = errno;

1730

2308

struct ifreq network;

1731

2309

unsigned int if_index = if_nametoindex(interface);

1732

2310

if(if_index == 0){

1735

2313

return ENXIO;

1736

2314

}

1737

2315

if(interface_is_up(interface)){

2316

int ret_errno = 0;

2317

int ioctl_errno = 0;

1738

2318

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

1739

2319

ret_errno = errno;

1740

2320

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

1741

2321

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

2322

errno = old_errno;

1742

2323

return ret_errno;

1743

2324

}

1744

2325

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

1745

2326

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

2327

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

2328

if(sd == -1){

1748

2329

ret_errno = errno;

1749

2330

perror_plus("socket");

1750

2331

errno = old_errno;

1756

2337

interface);

1757

2338

}

1758

2339

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

2340

/* Raise privileges */

2341

ret_errno = raise_privileges();

2342

if(ret_errno != 0){

2343

errno = ret_errno;

2344

perror_plus("Failed to raise privileges");

2345

}

2346

2347

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

2348

ioctl_errno = errno;

2349

2350

/* If raise_privileges() succeeded above */

2351

if(ret_errno == 0){

2352

/* Lower privileges */

2353

ret_errno = lower_privileges();

2354

if(ret_errno != 0){

2355

errno = ret_errno;

2356

perror_plus("Failed to lower privileges");

2357

}

2358

}

1767

2359

1768

2360

/* Close the socket */

1769

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

2361

int ret = close(sd);

1770

2362

if(ret == -1){

1771

2363

perror_plus("close");

1772

2364

}

1773

2365

1774

2366

if(ret_setflags == -1){

1775

errno = ret_errno;

2367

errno = ioctl_errno;

1776

2368

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1777

2369

errno = old_errno;

1778

return ret_errno;

2370

return ioctl_errno;

1779

2371

}

1780

2372

} else if(debug){

1781

2373

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

1787

2379

}

1788

2380

1789

2381

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

1790

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

1791

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

1792

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

1793

.interfaces = NULL, .interfaces_size = 0 };

2382

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

2383

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

2384

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2385

.current_server = NULL, .interfaces = NULL,

2386

.interfaces_size = 0 };

1794

2387

AvahiSServiceBrowser *sb = NULL;

1795

2388

error_t ret_errno;

1796

2389

int ret;

1799

2392

int exitcode = EXIT_SUCCESS;

1800

2393

char *interfaces_to_take_down = NULL;

1801

2394

size_t interfaces_to_take_down_size = 0;

1802

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

1803

bool tempdir_created = false;

2395

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

2396

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

2397

char *tempdir = NULL;

1804

2398

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1805

2399

const char *seckey = PATHDIR "/" SECKEY;

1806

2400

const char *pubkey = PATHDIR "/" PUBKEY;

2401

const char *dh_params_file = NULL;

1807

2402

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1809

2403

1810

2404

bool gnutls_initialized = false;

1811

2405

bool gpgme_initialized = false;

1863

2457

.doc = "Bit length of the prime number used in the"

1864

2458

" Diffie-Hellman key exchange",

1865

2459

.group = 2 },

2460

{ .name = "dh-params", .key = 134,

2461

.arg = "FILE",

2462

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2463

" for the Diffie-Hellman key exchange",

2464

.group = 2 },

1866

2465

{ .name = "priority", .key = 130,

1867

2466

.arg = "STRING",

1868

2467

.doc = "GnuTLS priority string for the TLS handshake",

1923

2522

}

1924

2523

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

1925

2524

break;

2525

case 134: /* --dh-params */

2526

dh_params_file = arg;

2527

break;

1926

2528

case 130: /* --priority */

1927

2529

mc.priority = arg;

1928

2530

break;

1968

2570

.args_doc = "",

1969

2571

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

1970

2572

" passwords from a Mandos server" };

1971

ret = argp_parse(&argp, argc, argv,

1972

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1973

switch(ret){

2573

ret_errno = argp_parse(&argp, argc, argv,

2574

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2575

switch(ret_errno){

1974

2576

case 0:

1975

2577

break;

1976

2578

case ENOMEM:

1977

2579

default:

1978

errno = ret;

2580

errno = ret_errno;

1979

2581

perror_plus("argp_parse");

1980

2582

exitcode = EX_OSERR;

1981

2583

goto end;

1984

2586

goto end;

1985

2587

}

1986

2588

}

1987

2589

1988

2590

{

1989

2591

/* Work around Debian bug #633582:

1990

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

2592

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

1991

2593

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2594

/* Re-raise privileges */

2595

ret = raise_privileges();

2596

if(ret != 0){

2597

errno = ret;

2598

perror_plus("Failed to raise privileges");

2599

} else {

1994

2600

struct stat st;

1995

2601

1996

2602

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

2010

2616

}

2011

2617

}

2012

2618

}

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2619

close(seckey_fd);

2014

2620

}

2015

2621

}

2016

2622

2017

2623

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

2018

2624

int pubkey_fd = open(pubkey, O_RDONLY);

2019

2625

if(pubkey_fd == -1){

2031

2637

}

2032

2638

}

2033

2639

}

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2640

close(pubkey_fd);

2641

}

2642

}

2643

2644

if(dh_params_file != NULL

2645

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2646

int dhparams_fd = open(dh_params_file, O_RDONLY);

2647

if(dhparams_fd == -1){

2648

perror_plus("open");

2649

} else {

2650

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

2651

if(ret == -1){

2652

perror_plus("fstat");

2653

} else {

2654

if(S_ISREG(st.st_mode)

2655

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

2656

ret = fchown(dhparams_fd, uid, gid);

2657

if(ret == -1){

2658

perror_plus("fchown");

2659

}

2660

}

2661

}

2662

close(dhparams_fd);

2663

}

2664

}

2665

2038

2666

/* Lower privileges */

2039

lower_privileges();

2667

ret = lower_privileges();

2668

if(ret != 0){

2669

errno = ret;

2670

perror_plus("Failed to lower privileges");

2671

}

2040

2672

}

2041

2673

}

2042

2674

2066

2698

goto end;

2067

2699

}

2068

2700

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

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

2072

}

2073

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

2074

interfaces_hooks : "", delay)){

2075

goto end;

2076

}

2701

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

2702

}

2703

run_network_hooks("start", interfaces_hooks != NULL ?

2704

interfaces_hooks : "", delay);

2077

2705

}

2078

2706

2079

2707

if(not debug){

2157

2785

2158

2786

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

2159

2787

if(mc.interfaces == NULL){

2160

struct dirent **direntries;

2788

struct dirent **direntries = NULL;

2161

2789

/* Look for any good interfaces */

2162

2790

ret = scandir(sys_class_net, &direntries, good_interface,

2163

2791

alphasort);

2167

2795

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

2168

2796

direntries[i]->d_name);

2169

2797

if(ret_errno != 0){

2798

errno = ret_errno;

2170

2799

perror_plus("argz_add");

2800

free(direntries[i]);

2171

2801

continue;

2172

2802

}

2173

2803

if(debug){

2174

2804

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

2175

2805

direntries[i]->d_name);

2176

2806

}

2807

free(direntries[i]);

2177

2808

}

2178

2809

free(direntries);

2179

2810

} else {

2180

free(direntries);

2811

if(ret == 0){

2812

free(direntries);

2813

}

2181

2814

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

2182

2815

exitcode = EXIT_FAILURE;

2183

2816

goto end;

2206

2839

break;

2207

2840

}

2208

2841

bool interface_was_up = interface_is_up(interface);

2209

ret = bring_up_interface(interface, delay);

2842

errno = bring_up_interface(interface, delay);

2210

2843

if(not interface_was_up){

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2844

if(errno != 0){

2845

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2846

" %s\n", interface, strerror(errno));

2214

2847

} else {

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2848

errno = argz_add(&interfaces_to_take_down,

2849

&interfaces_to_take_down_size,

2850

interface);

2851

if(errno != 0){

2852

perror_plus("argz_add");

2853

}

2218

2854

}

2219

2855

}

2220

2856

}

2236

2872

goto end;

2237

2873

}

2238

2874

2239

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

2875

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

2240

2876

if(ret == -1){

2241

2877

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

2242

2878

exitcode = EX_UNAVAILABLE;

2249

2885

goto end;

2250

2886

}

2251

2887

2252

if(mkdtemp(tempdir) == NULL){

2888

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

2889

tempdir = mkdtemp(run_tempdir);

2890

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

2891

if(debug){

2892

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

2893

run_tempdir, old_tempdir);

2894

}

2895

tempdir = mkdtemp(old_tempdir);

2896

}

2897

if(tempdir == NULL){

2253

2898

perror_plus("mkdtemp");

2254

2899

goto end;

2255

2900

}

2256

tempdir_created = true;

2257

2901

2258

2902

if(quit_now){

2259

2903

goto end;

2334

2978

sleep((unsigned int)retry_interval);

2335

2979

}

2336

2980

2337

if (not quit_now){

2981

if(not quit_now){

2338

2982

exitcode = EXIT_SUCCESS;

2339

2983

}

2340

2984

2356

3000

2357

3001

/* Allocate a new server */

2358

3002

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2359

&config, NULL, NULL, &ret_errno);

3003

&config, NULL, NULL, &ret);

2360

3004

2361

3005

/* Free the Avahi configuration data */

2362

3006

avahi_server_config_free(&config);

2365

3009

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

2366

3010

if(mc.server == NULL){

2367

3011

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

2368

avahi_strerror(ret_errno));

3012

avahi_strerror(ret));

2369

3013

exitcode = EX_UNAVAILABLE;

2370

3014

goto end;

2371

3015

}

2395

3039

if(debug){

2396

3040

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

2397

3041

}

2398

3042

2399

3043

ret = avahi_loop_with_timeout(simple_poll,

2400

3044

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

2401

3045

if(debug){

2406

3050

end:

2407

3051

2408

3052

if(debug){

2409

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

3053

if(signal_received){

3054

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

3055

argv[0], signal_received,

3056

strsignal(signal_received));

3057

} else {

3058

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

3059

}

2410

3060

}

2411

3061

2412

3062

/* Cleanup things */

2423

3073

2424

3074

if(gnutls_initialized){

2425

3075

gnutls_certificate_free_credentials(mc.cred);

2426

gnutls_global_deinit();

2427

3076

gnutls_dh_params_deinit(mc.dh_params);

2428

3077

}

2429

3078

2437

3086

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

2438

3087

while(mc.current_server != NULL){

2439

3088

server *next = mc.current_server->next;

3089

#ifdef __GNUC__

3090

#pragma GCC diagnostic push

3091

#pragma GCC diagnostic ignored "-Wcast-qual"

3092

#endif

3093

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

3094

#ifdef __GNUC__

3095

#pragma GCC diagnostic pop

3096

#endif

2440

3097

free(mc.current_server);

2441

3098

mc.current_server = next;

2442

3099

}

2443

3100

}

2444

3101

2445

/* Re-raise priviliges */

3102

/* Re-raise privileges */

2446

3103

{

2447

raise_privileges();

2448

2449

/* Run network hooks */

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2452

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

2463

}

2464

}

2465

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

2466

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

2467

" down\n");

2468

}

2469

}

2470

2471

lower_privileges_permanently();

3104

ret = raise_privileges();

3105

if(ret != 0){

3106

errno = ret;

3107

perror_plus("Failed to raise privileges");

3108

} else {

3109

3110

/* Run network hooks */

3111

run_network_hooks("stop", interfaces_hooks != NULL ?

3112

interfaces_hooks : "", delay);

3113

3114

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

3115

{

3116

char *interface = NULL;

3117

while((interface = argz_next(interfaces_to_take_down,

3118

interfaces_to_take_down_size,

3119

interface))){

3120

ret = take_down_interface(interface);

3121

if(ret != 0){

3122

errno = ret;

3123

perror_plus("Failed to take down interface");

3124

}

3125

}

3126

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

3127

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

3128

" down\n");

3129

}

3130

}

3131

}

3132

3133

ret = lower_privileges_permanently();

3134

if(ret != 0){

3135

errno = ret;

3136

perror_plus("Failed to lower privileges permanently");

3137

}

2472

3138

}

2473

3139

2474

3140

free(interfaces_to_take_down);

2475

3141

free(interfaces_hooks);

2476

3142

3143

void clean_dir_at(int base, const char * const dirname,

3144

uintmax_t level){

3145

struct dirent **direntries = NULL;

3146

int dret;

3147

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3148

O_RDONLY

3149

| O_NOFOLLOW

3150

| O_DIRECTORY

3151

| O_PATH));

3152

if(dir_fd == -1){

3153

perror_plus("open");

3154

return;

3155

}

3156

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

3157

notdotentries, alphasort);

3158

if(numentries >= 0){

3159

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

3160

if(debug){

3161

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3162

dirname, direntries[i]->d_name);

3163

}

3164

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3165

if(dret == -1){

3166

if(errno == EISDIR){

3167

dret = unlinkat(dir_fd, direntries[i]->d_name,

3168

AT_REMOVEDIR);

3169

}

3170

if((dret == -1) and (errno == ENOTEMPTY)

3171

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3172

== 0) and (level == 0)){

3173

/* Recurse only in this special case */

3174

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3175

dret = 0;

3176

}

3177

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

3178

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3179

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

3180

}

3181

}

3182

free(direntries[i]);

3183

}

3184

3185

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

3186

free(direntries);

3187

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3188

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

3189

perror_plus("rmdir");

3190

}

3191

} else {

3192

perror_plus("scandirat");

3193

}

3194

close(dir_fd);

3195

}

3196

2477

3197

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

2478

if(tempdir_created){

2479

struct dirent **direntries = NULL;

2480

struct dirent *direntry = NULL;

2481

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

2482

alphasort);

2483

if (numentries > 0){

2484

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

2485

direntry = direntries[i];

2486

char *fullname = NULL;

2487

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

2488

direntry->d_name);

2489

if(ret < 0){

2490

perror_plus("asprintf");

2491

continue;

2492

}

2493

ret = remove(fullname);

2494

if(ret == -1){

2495

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

2496

strerror(errno));

2497

}

2498

free(fullname);

2499

}

2500

}

2501

2502

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

2503

free(direntries);

2504

if (numentries == -1){

2505

perror_plus("scandir");

2506

}

2507

ret = rmdir(tempdir);

2508

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

2509

perror_plus("rmdir");

2510

}

3198

if(tempdir != NULL){

3199

clean_dir_at(-1, tempdir, 0);

2511

3200

}

2512

3201

2513

3202

if(quit_now){