/mandos/release : revision 237.7.453

9

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

10

*

11

* Everything else is

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13

12

13

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*

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

38

#endif

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#endif /* not _FILE_OFFSET_BITS */

39

40

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

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42

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

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stdout, ferror(), remove() */

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stdout, ferror() */

44

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

45

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

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

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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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*/

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52

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

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53

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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57

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

60

getnameinfo() */

61

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

60

62

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

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63

*/

62

64

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

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65

strtoimax() */

64

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

66

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

67

EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

69

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

70

ENOTEMPTY,

65

71

program_invocation_short_name */

66

72

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

67

73

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

72

78

*/

73

79

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

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80

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

75

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

76

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

81

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

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unlinkat() */

83

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

77

84

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

78

85

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

79

86

argp_state, struct argp,

91

98

argz_delete(), argz_append(),

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99

argz_stringify(), argz_add(),

93

100

argz_count() */

101

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

102

EAI_SYSTEM, gai_strerror() */

94

103

95

104

#ifdef __linux__

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105

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

138

147

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

139

148

char *connect_to = NULL;

140

149

const char *hookdir = HOOKDIR;

150

int hookdir_fd = -1;

141

151

uid_t uid = 65534;

142

152

gid_t gid = 65534;

143

153

154

164

155

165

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

156

166

typedef struct {

157

AvahiSimplePoll *simple_poll;

158

167

AvahiServer *server;

159

168

gnutls_certificate_credentials_t cred;

160

169

unsigned int dh_bits;

162

171

const char *priority;

163

172

gpgme_ctx_t ctx;

164

173

server *current_server;

174

char *interfaces;

175

size_t interfaces_size;

165

176

} mandos_context;

166

177

167

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

168

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

169

.dh_bits = 1024, .priority = "SECURE256"

170

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

171

.current_server = NULL };

178

/* global so signal handler can reach it*/

179

AvahiSimplePoll *simple_poll;

172

180

173

181

sig_atomic_t quit_now = 0;

174

182

int signal_received = 0;

182

190

perror(print_text);

183

191

}

184

192

185

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

193

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

186

194

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

187

195

va_list ap;

188

196

va_start (ap, format);

189

197

190

198

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

191

199

program_invocation_short_name));

192

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

200

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

193

201

}

194

202

195

203

/*

197

205

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

198

206

* "buffer_length" is how much is already used.

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207

*/

208

__attribute__((nonnull, warn_unused_result))

200

209

size_t incbuffer(char **buffer, size_t buffer_length,

201

210

size_t buffer_capacity){

202

211

if(buffer_length + BUFFER_SIZE > buffer_capacity){

203

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

204

if(buffer == NULL){

212

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

213

if(new_buf == NULL){

214

int old_errno = errno;

215

free(*buffer);

216

errno = old_errno;

217

*buffer = NULL;

205

218

return 0;

206

219

}

220

*buffer = new_buf;

207

221

buffer_capacity += BUFFER_SIZE;

208

222

}

209

223

return buffer_capacity;

210

224

}

211

225

212

226

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

227

__attribute__((nonnull, warn_unused_result))

213

228

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

214

int af){

229

int af, server **current_server){

215

230

int ret;

216

231

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

217

232

if(new_server == NULL){

224

239

.af = af };

225

240

if(new_server->ip == NULL){

226

241

perror_plus("strdup");

242

free(new_server);

243

return false;

244

}

245

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

246

if(ret == -1){

247

perror_plus("clock_gettime");

248

#ifdef __GNUC__

249

#pragma GCC diagnostic push

250

#pragma GCC diagnostic ignored "-Wcast-qual"

251

#endif

252

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

253

#ifdef __GNUC__

254

#pragma GCC diagnostic pop

255

#endif

256

free(new_server);

227

257

return false;

228

258

}

229

259

/* Special case of first server */

230

if (mc.current_server == NULL){

260

if(*current_server == NULL){

231

261

new_server->next = new_server;

232

262

new_server->prev = new_server;

233

mc.current_server = new_server;

234

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

263

*current_server = new_server;

235

264

} else {

236

new_server->next = mc.current_server;

237

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

265

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

266

new_server->next = *current_server;

267

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

238

268

new_server->prev->next = new_server;

239

mc.current_server->prev = new_server;

240

}

241

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

242

if(ret == -1){

243

perror_plus("clock_gettime");

244

return false;

269

(*current_server)->prev = new_server;

245

270

}

246

271

return true;

247

272

}

249

274

/*

250

275

* Initialize GPGME.

251

276

*/

252

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

253

const char *tempdir){

277

__attribute__((nonnull, warn_unused_result))

278

static bool init_gpgme(const char * const seckey,

279

const char * const pubkey,

280

const char * const tempdir,

281

mandos_context *mc){

254

282

gpgme_error_t rc;

255

283

gpgme_engine_info_t engine_info;

256

284

257

258

285

/*

259

286

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

260

287

*/

261

bool import_key(const char *filename){

288

bool import_key(const char * const filename){

262

289

int ret;

263

290

int fd;

264

291

gpgme_data_t pgp_data;

276

303

return false;

277

304

}

278

305

279

rc = gpgme_op_import(mc.ctx, pgp_data);

306

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

280

307

if(rc != GPG_ERR_NO_ERROR){

281

308

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

282

309

gpgme_strsource(rc), gpgme_strerror(rc));

283

310

return false;

284

311

}

285

312

286

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

313

ret = close(fd);

287

314

if(ret == -1){

288

315

perror_plus("close");

289

316

}

326

353

}

327

354

328

355

/* Create new GPGME "context" */

329

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

356

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

330

357

if(rc != GPG_ERR_NO_ERROR){

331

358

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

332

359

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

345

372

* Decrypt OpenPGP data.

346

373

* Returns -1 on error

347

374

*/

375

__attribute__((nonnull, warn_unused_result))

348

376

static ssize_t pgp_packet_decrypt(const char *cryptotext,

349

377

size_t crypto_size,

350

char **plaintext){

378

char **plaintext,

379

mandos_context *mc){

351

380

gpgme_data_t dh_crypto, dh_plain;

352

381

gpgme_error_t rc;

353

382

ssize_t ret;

379

408

380

409

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

381

410

data buffer */

382

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

411

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

383

412

if(rc != GPG_ERR_NO_ERROR){

384

413

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

385

414

gpgme_strsource(rc), gpgme_strerror(rc));

386

415

plaintext_length = -1;

387

416

if(debug){

388

417

gpgme_decrypt_result_t result;

389

result = gpgme_op_decrypt_result(mc.ctx);

418

result = gpgme_op_decrypt_result(mc->ctx);

390

419

if(result == NULL){

391

420

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

392

421

} else {

469

498

return plaintext_length;

470

499

}

471

500

472

static const char * safer_gnutls_strerror(int value){

501

__attribute__((warn_unused_result, const))

502

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

503

if(str == NULL)

504

return "(unknown)";

505

return str;

506

}

507

508

__attribute__((warn_unused_result))

509

static const char *safer_gnutls_strerror(int value){

473

510

const char *ret = gnutls_strerror(value);

474

if(ret == NULL)

475

ret = "(unknown)";

476

return ret;

511

return safe_string(ret);

477

512

}

478

513

479

514

/* GnuTLS log function callback */

515

__attribute__((nonnull))

480

516

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

481

517

const char* string){

482

518

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

483

519

}

484

520

521

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

485

522

static int init_gnutls_global(const char *pubkeyfilename,

486

const char *seckeyfilename){

523

const char *seckeyfilename,

524

const char *dhparamsfilename,

525

mandos_context *mc){

487

526

int ret;

527

unsigned int uret;

488

528

489

529

if(debug){

490

530

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

491

531

}

492

532

493

ret = gnutls_global_init();

494

if(ret != GNUTLS_E_SUCCESS){

495

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

496

safer_gnutls_strerror(ret));

497

return -1;

498

}

499

500

533

if(debug){

501

534

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

502

535

* - GnuTLS manual

506

539

}

507

540

508

541

/* OpenPGP credentials */

509

ret = gnutls_certificate_allocate_credentials(&mc.cred);

542

ret = gnutls_certificate_allocate_credentials(&mc->cred);

510

543

if(ret != GNUTLS_E_SUCCESS){

511

544

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

512

545

safer_gnutls_strerror(ret));

513

gnutls_global_deinit();

514

546

return -1;

515

547

}

516

548

522

554

}

523

555

524

556

ret = gnutls_certificate_set_openpgp_key_file

525

(mc.cred, pubkeyfilename, seckeyfilename,

557

(mc->cred, pubkeyfilename, seckeyfilename,

526

558

GNUTLS_OPENPGP_FMT_BASE64);

527

559

if(ret != GNUTLS_E_SUCCESS){

528

560

fprintf_plus(stderr,

534

566

}

535

567

536

568

/* GnuTLS server initialization */

537

ret = gnutls_dh_params_init(&mc.dh_params);

569

ret = gnutls_dh_params_init(&mc->dh_params);

538

570

if(ret != GNUTLS_E_SUCCESS){

539

571

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

540

572

" initialization: %s\n",

541

573

safer_gnutls_strerror(ret));

542

574

goto globalfail;

543

575

}

544

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

545

if(ret != GNUTLS_E_SUCCESS){

546

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

547

safer_gnutls_strerror(ret));

548

goto globalfail;

549

}

550

551

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

576

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

577

if(dhparamsfilename != NULL){

578

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

579

do {

580

int dhpfile = open(dhparamsfilename, O_RDONLY);

581

if(dhpfile == -1){

582

perror_plus("open");

583

dhparamsfilename = NULL;

584

break;

585

}

586

size_t params_capacity = 0;

587

while(true){

588

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

589

(size_t)params.size,

590

(size_t)params_capacity);

591

if(params_capacity == 0){

592

perror_plus("incbuffer");

593

free(params.data);

594

params.data = NULL;

595

dhparamsfilename = NULL;

596

break;

597

}

598

ssize_t bytes_read = read(dhpfile,

599

params.data + params.size,

600

BUFFER_SIZE);

601

/* EOF */

602

if(bytes_read == 0){

603

break;

604

}

605

/* check bytes_read for failure */

606

if(bytes_read < 0){

607

perror_plus("read");

608

free(params.data);

609

params.data = NULL;

610

dhparamsfilename = NULL;

611

break;

612

}

613

params.size += (unsigned int)bytes_read;

614

}

615

if(params.data == NULL){

616

dhparamsfilename = NULL;

617

}

618

if(dhparamsfilename == NULL){

619

break;

620

}

621

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

622

GNUTLS_X509_FMT_PEM);

623

if(ret != GNUTLS_E_SUCCESS){

624

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

625

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

626

safer_gnutls_strerror(ret));

627

dhparamsfilename = NULL;

628

}

629

free(params.data);

630

} while(false);

631

}

632

if(dhparamsfilename == NULL){

633

if(mc->dh_bits == 0){

634

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

635

/* Try to read the private key file */

636

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

637

do {

638

int secfile = open(seckeyfilename, O_RDONLY);

639

if(secfile == -1){

640

perror_plus("open");

641

break;

642

}

643

size_t buffer_capacity = 0;

644

while(true){

645

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

646

(size_t)buffer.size,

647

(size_t)buffer_capacity);

648

if(buffer_capacity == 0){

649

perror_plus("incbuffer");

650

free(buffer.data);

651

buffer.data = NULL;

652

break;

653

}

654

ssize_t bytes_read = read(secfile,

655

buffer.data + buffer.size,

656

BUFFER_SIZE);

657

/* EOF */

658

if(bytes_read == 0){

659

break;

660

}

661

/* check bytes_read for failure */

662

if(bytes_read < 0){

663

perror_plus("read");

664

free(buffer.data);

665

buffer.data = NULL;

666

break;

667

}

668

buffer.size += (unsigned int)bytes_read;

669

}

670

close(secfile);

671

} while(false);

672

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

673

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

674

if(buffer.data != NULL){

675

{

676

gnutls_openpgp_privkey_t privkey = NULL;

677

ret = gnutls_openpgp_privkey_init(&privkey);

678

if(ret != GNUTLS_E_SUCCESS){

679

fprintf_plus(stderr, "Error initializing OpenPGP key"

680

" structure: %s",

681

safer_gnutls_strerror(ret));

682

free(buffer.data);

683

buffer.data = NULL;

684

} else {

685

ret = gnutls_openpgp_privkey_import

686

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

687

if(ret != GNUTLS_E_SUCCESS){

688

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

689

safer_gnutls_strerror(ret));

690

privkey = NULL;

691

}

692

free(buffer.data);

693

buffer.data = NULL;

694

if(privkey != NULL){

695

/* Use private key to suggest an appropriate

696

sec_param */

697

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

698

gnutls_openpgp_privkey_deinit(privkey);

699

if(debug){

700

fprintf_plus(stderr, "This OpenPGP key implies using"

701

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

702

safe_string(gnutls_sec_param_get_name

703

(sec_param)));

704

}

705

}

706

}

707

}

708

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

709

/* Err on the side of caution */

710

sec_param = GNUTLS_SEC_PARAM_ULTRA;

711

if(debug){

712

fprintf_plus(stderr, "Falling back to security parameter"

713

" \"%s\"\n",

714

safe_string(gnutls_sec_param_get_name

715

(sec_param)));

716

}

717

}

718

}

719

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

720

if(uret != 0){

721

mc->dh_bits = uret;

722

if(debug){

723

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

724

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

725

safe_string(gnutls_sec_param_get_name

726

(sec_param)),

727

mc->dh_bits);

728

}

729

} else {

730

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

731

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

732

safe_string(gnutls_sec_param_get_name

733

(sec_param)),

734

safer_gnutls_strerror(ret));

735

goto globalfail;

736

}

737

} else if(debug){

738

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

739

mc->dh_bits);

740

}

741

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

742

if(ret != GNUTLS_E_SUCCESS){

743

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

744

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

745

safer_gnutls_strerror(ret));

746

goto globalfail;

747

}

748

}

749

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

552

750

553

751

return 0;

554

752

555

753

globalfail:

556

754

557

gnutls_certificate_free_credentials(mc.cred);

558

gnutls_global_deinit();

559

gnutls_dh_params_deinit(mc.dh_params);

755

gnutls_certificate_free_credentials(mc->cred);

756

gnutls_dh_params_deinit(mc->dh_params);

560

757

return -1;

561

758

}

562

759

563

static int init_gnutls_session(gnutls_session_t *session){

760

__attribute__((nonnull, warn_unused_result))

761

static int init_gnutls_session(gnutls_session_t *session,

762

mandos_context *mc){

564

763

int ret;

565

764

/* GnuTLS session creation */

566

765

do {

578

777

{

579

778

const char *err;

580

779

do {

581

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

780

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

582

781

if(quit_now){

583

782

gnutls_deinit(*session);

584

783

return -1;

595

794

596

795

do {

597

796

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

598

mc.cred);

797

mc->cred);

599

798

if(quit_now){

600

799

gnutls_deinit(*session);

601

800

return -1;

611

810

/* ignore client certificate if any. */

612

811

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

613

812

614

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

615

616

813

return 0;

617

814

}

618

815

620

817

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

621

818

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

622

819

820

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

821

__attribute__((warn_unused_result))

822

int raise_privileges(void){

823

int old_errno = errno;

824

int ret = 0;

825

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

826

ret = errno;

827

}

828

errno = old_errno;

829

return ret;

830

}

831

832

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

833

__attribute__((warn_unused_result))

834

int raise_privileges_permanently(void){

835

int old_errno = errno;

836

int ret = raise_privileges();

837

if(ret != 0){

838

errno = old_errno;

839

return ret;

840

}

841

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

842

ret = errno;

843

}

844

errno = old_errno;

845

return ret;

846

}

847

848

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

849

__attribute__((warn_unused_result))

850

int lower_privileges(void){

851

int old_errno = errno;

852

int ret = 0;

853

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

854

ret = errno;

855

}

856

errno = old_errno;

857

return ret;

858

}

859

860

/* Lower privileges permanently */

861

__attribute__((warn_unused_result))

862

int lower_privileges_permanently(void){

863

int old_errno = errno;

864

int ret = 0;

865

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

866

ret = errno;

867

}

868

errno = old_errno;

869

return ret;

870

}

871

872

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

873

__attribute__((nonnull, warn_unused_result))

874

static bool add_delete_local_route(const bool add,

875

const char *address,

876

AvahiIfIndex if_index){

877

int ret;

878

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

879

char add_arg[] = "add";

880

char delete_arg[] = "delete";

881

char debug_flag[] = "--debug";

882

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

883

if(pluginhelperdir == NULL){

884

if(debug){

885

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

886

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

887

}

888

return false;

889

}

890

891

char interface[IF_NAMESIZE];

892

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

893

perror_plus("if_indextoname");

894

return false;

895

}

896

897

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

898

if(devnull == -1){

899

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

900

return false;

901

}

902

pid_t pid = fork();

903

if(pid == 0){

904

/* Child */

905

/* Raise privileges */

906

errno = raise_privileges_permanently();

907

if(errno != 0){

908

perror_plus("Failed to raise privileges");

909

/* _exit(EX_NOPERM); */

910

} else {

911

/* Set group */

912

errno = 0;

913

ret = setgid(0);

914

if(ret == -1){

915

perror_plus("setgid");

916

_exit(EX_NOPERM);

917

}

918

/* Reset supplementary groups */

919

errno = 0;

920

ret = setgroups(0, NULL);

921

if(ret == -1){

922

perror_plus("setgroups");

923

_exit(EX_NOPERM);

924

}

925

}

926

ret = dup2(devnull, STDIN_FILENO);

927

if(ret == -1){

928

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

929

_exit(EX_OSERR);

930

}

931

ret = close(devnull);

932

if(ret == -1){

933

perror_plus("close");

934

_exit(EX_OSERR);

935

}

936

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

937

if(ret == -1){

938

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

939

_exit(EX_OSERR);

940

}

941

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

942

O_RDONLY

943

| O_DIRECTORY

944

| O_PATH

945

| O_CLOEXEC));

946

if(helperdir_fd == -1){

947

perror_plus("open");

948

_exit(EX_UNAVAILABLE);

949

}

950

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

951

helper, O_RDONLY));

952

if(helper_fd == -1){

953

perror_plus("openat");

954

close(helperdir_fd);

955

_exit(EX_UNAVAILABLE);

956

}

957

close(helperdir_fd);

958

#ifdef __GNUC__

959

#pragma GCC diagnostic push

960

#pragma GCC diagnostic ignored "-Wcast-qual"

961

#endif

962

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

963

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

964

interface, debug ? debug_flag : NULL, NULL },

965

environ) == -1){

966

#ifdef __GNUC__

967

#pragma GCC diagnostic pop

968

#endif

969

perror_plus("fexecve");

970

_exit(EXIT_FAILURE);

971

}

972

}

973

if(pid == -1){

974

perror_plus("fork");

975

return false;

976

}

977

int status;

978

pid_t pret = -1;

979

errno = 0;

980

do {

981

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

982

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

983

int errno_raising = 0;

984

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

985

errno_raising = errno;

986

perror_plus("Failed to raise privileges in order to"

987

" kill helper program");

988

}

989

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

990

perror_plus("kill");

991

}

992

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

993

perror_plus("Failed to lower privileges after killing"

994

" helper program");

995

}

996

return false;

997

}

998

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

999

if(pret == -1){

1000

perror_plus("waitpid");

1001

return false;

1002

}

1003

if(WIFEXITED(status)){

1004

if(WEXITSTATUS(status) != 0){

1005

fprintf_plus(stderr, "Error: iprouteadddel exited"

1006

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

1007

return false;

1008

}

1009

return true;

1010

}

1011

if(WIFSIGNALED(status)){

1012

fprintf_plus(stderr, "Error: iprouteadddel died by"

1013

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

1014

return false;

1015

}

1016

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

1017

return false;

1018

}

1019

1020

__attribute__((nonnull, warn_unused_result))

1021

static bool add_local_route(const char *address,

1022

AvahiIfIndex if_index){

1023

if(debug){

1024

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

1025

}

1026

return add_delete_local_route(true, address, if_index);

1027

}

1028

1029

__attribute__((nonnull, warn_unused_result))

1030

static bool delete_local_route(const char *address,

1031

AvahiIfIndex if_index){

1032

if(debug){

1033

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

1034

}

1035

return add_delete_local_route(false, address, if_index);

1036

}

1037

623

1038

/* Called when a Mandos server is found */

1039

__attribute__((nonnull, warn_unused_result))

624

1040

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

625

1041

AvahiIfIndex if_index,

626

int af){

1042

int af, mandos_context *mc){

627

1043

int ret, tcp_sd = -1;

628

1044

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1045

struct sockaddr_storage to;

633

1046

char *buffer = NULL;

634

1047

char *decrypted_buffer = NULL;

635

1048

size_t buffer_length = 0;

638

1051

int retval = -1;

639

1052

gnutls_session_t session;

640

1053

int pf; /* Protocol family */

1054

bool route_added = false;

641

1055

642

1056

errno = 0;

643

1057

659

1073

return -1;

660

1074

}

661

1075

662

ret = init_gnutls_session(&session);

1076

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

1077

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

1078

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

1079

bool match = false;

1080

{

1081

char *interface = NULL;

1082

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

1083

mc->interfaces_size,

1084

interface))){

1085

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

1086

match = true;

1087

break;

1088

}

1089

}

1090

}

1091

if(not match){

1092

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

1093

connect to the server */

1094

if(debug){

1095

char interface[IF_NAMESIZE];

1096

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

1097

perror_plus("if_indextoname");

1098

} else {

1099

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

1100

" \"%s\"\n",

1101

if_indextoname((unsigned int)if_index,

1102

interface));

1103

}

1104

}

1105

return -1;

1106

}

1107

}

1108

1109

ret = init_gnutls_session(&session, mc);

663

1110

if(ret != 0){

664

1111

return -1;

665

1112

}

669

1116

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

670

1117

}

671

1118

672

tcp_sd = socket(pf, SOCK_STREAM, 0);

1119

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

673

1120

if(tcp_sd < 0){

674

1121

int e = errno;

675

1122

perror_plus("socket");

682

1129

goto mandos_end;

683

1130

}

684

1131

685

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

686

1132

if(af == AF_INET6){

687

to.in6.sin6_family = (sa_family_t)af;

688

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

1133

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

1134

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

1135

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

689

1136

} else { /* IPv4 */

690

to.in.sin_family = (sa_family_t)af;

691

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

1137

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

1138

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

1139

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

692

1140

}

693

1141

if(ret < 0 ){

694

1142

int e = errno;

703

1151

goto mandos_end;

704

1152

}

705

1153

if(af == AF_INET6){

706

to.in6.sin6_port = htons(port);

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

708

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

709

-Wunreachable-code*/

1154

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

1155

if(IN6_IS_ADDR_LINKLOCAL

1156

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

710

1157

if(if_index == AVAHI_IF_UNSPEC){

711

1158

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

712

1159

" incomplete without a network interface\n");

714

1161

goto mandos_end;

715

1162

}

716

1163

/* Set the network interface number as scope */

717

to.in6.sin6_scope_id = (uint32_t)if_index;

1164

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

718

1165

}

719

1166

} else {

720

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

721

-Wconversion and

722

-Wunreachable-code */

1167

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

723

1168

}

724

1169

725

1170

if(quit_now){

742

1187

}

743

1188

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

744

1189

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

745

const char *pcret;

746

if(af == AF_INET6){

747

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

748

sizeof(addrstr));

749

} else {

750

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

751

sizeof(addrstr));

752

}

753

if(pcret == NULL){

754

perror_plus("inet_ntop");

755

} else {

756

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

757

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

758

}

759

}

760

}

761

762

if(quit_now){

763

errno = EINTR;

764

goto mandos_end;

765

}

766

767

if(af == AF_INET6){

768

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

769

} else {

770

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

771

}

772

if(ret < 0){

773

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

774

int e = errno;

775

perror_plus("connect");

776

errno = e;

777

}

778

goto mandos_end;

779

}

780

781

if(quit_now){

782

errno = EINTR;

783

goto mandos_end;

1190

if(af == AF_INET6){

1191

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

1192

sizeof(struct sockaddr_in6),

1193

addrstr, sizeof(addrstr), NULL, 0,

1194

NI_NUMERICHOST);

1195

} else {

1196

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

1197

sizeof(struct sockaddr_in),

1198

addrstr, sizeof(addrstr), NULL, 0,

1199

NI_NUMERICHOST);

1200

}

1201

if(ret == EAI_SYSTEM){

1202

perror_plus("getnameinfo");

1203

} else if(ret != 0) {

1204

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

1205

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

1206

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

1207

}

1208

}

1209

1210

if(quit_now){

1211

errno = EINTR;

1212

goto mandos_end;

1213

}

1214

1215

while(true){

1216

if(af == AF_INET6){

1217

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

1218

sizeof(struct sockaddr_in6));

1219

} else {

1220

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

1221

sizeof(struct sockaddr_in));

1222

}

1223

if(ret < 0){

1224

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

1225

and if_index != AVAHI_IF_UNSPEC

1226

and connect_to == NULL

1227

and not route_added and

1228

((af == AF_INET6 and not

1229

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1230

&to)->sin6_addr)))

1231

or (af == AF_INET and

1232

/* Not a a IPv4LL address */

1233

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

1234

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

1235

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

1236

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

1237

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

1238

connect to a Mandos server announced by Avahi on a server

1239

host with a global address. Work around this by retrying

1240

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

1241

1242

Avahi bug reference:

1243

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

1244

https://bugs.debian.org/587961

1245

*/

1246

if(debug){

1247

fprintf_plus(stderr, "Mandos server unreachable, trying"

1248

" direct route\n");

1249

}

1250

int e = errno;

1251

route_added = add_local_route(ip, if_index);

1252

if(route_added){

1253

continue;

1254

}

1255

errno = e;

1256

}

1257

if(errno != ECONNREFUSED or debug){

1258

int e = errno;

1259

perror_plus("connect");

1260

errno = e;

1261

}

1262

goto mandos_end;

1263

}

1264

1265

if(quit_now){

1266

errno = EINTR;

1267

goto mandos_end;

1268

}

1269

break;

784

1270

}

785

1271

786

1272

const char *out = mandos_protocol_version;

937

1423

if(buffer_length > 0){

938

1424

ssize_t decrypted_buffer_size;

939

1425

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

940

&decrypted_buffer);

1426

&decrypted_buffer, mc);

941

1427

if(decrypted_buffer_size >= 0){

942

1428

1429

clearerr(stdout);

943

1430

written = 0;

944

1431

while(written < (size_t) decrypted_buffer_size){

945

1432

if(quit_now){

961

1448

}

962

1449

written += (size_t)ret;

963

1450

}

1451

ret = fflush(stdout);

1452

if(ret != 0){

1453

int e = errno;

1454

if(debug){

1455

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

1456

strerror(errno));

1457

}

1458

errno = e;

1459

goto mandos_end;

1460

}

964

1461

retval = 0;

965

1462

}

966

1463

}

969

1466

970

1467

mandos_end:

971

1468

{

1469

if(route_added){

1470

if(not delete_local_route(ip, if_index)){

1471

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

1472

" interface %d", ip, if_index);

1473

}

1474

}

972

1475

int e = errno;

973

1476

free(decrypted_buffer);

974

1477

free(buffer);

975

1478

if(tcp_sd >= 0){

976

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

1479

ret = close(tcp_sd);

977

1480

}

978

1481

if(ret == -1){

979

1482

if(e == 0){

1004

1507

AVAHI_GCC_UNUSED AvahiStringList *txt,

1005

1508

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1006

1509

flags,

1007

AVAHI_GCC_UNUSED void* userdata){

1510

void *mc){

1008

1511

if(r == NULL){

1009

1512

return;

1010

1513

}

1013

1516

timed out */

1014

1517

1015

1518

if(quit_now){

1519

avahi_s_service_resolver_free(r);

1016

1520

return;

1017

1521

}

1018

1522

1022

1526

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

1023

1527

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

1024

1528

domain,

1025

avahi_strerror(avahi_server_errno(mc.server)));

1529

avahi_strerror(avahi_server_errno

1530

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

1026

1531

break;

1027

1532

1028

1533

case AVAHI_RESOLVER_FOUND:

1036

1541

}

1037

1542

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

1038

1543

interface,

1039

avahi_proto_to_af(proto));

1544

avahi_proto_to_af(proto),

1545

mc);

1040

1546

if(ret == 0){

1041

avahi_simple_poll_quit(mc.simple_poll);

1547

avahi_simple_poll_quit(simple_poll);

1042

1548

} else {

1043

1549

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

1044

avahi_proto_to_af(proto))){

1550

avahi_proto_to_af(proto),

1551

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

1045

1552

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

1046

1553

" list\n", name);

1047

1554

}

1060

1567

const char *domain,

1061

1568

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1062

1569

flags,

1063

AVAHI_GCC_UNUSED void* userdata){

1570

void *mc){

1064

1571

if(b == NULL){

1065

1572

return;

1066

1573

}

1077

1584

case AVAHI_BROWSER_FAILURE:

1078

1585

1079

1586

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

1081

avahi_simple_poll_quit(mc.simple_poll);

1587

avahi_strerror(avahi_server_errno

1588

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

1589

avahi_simple_poll_quit(simple_poll);

1082

1590

return;

1083

1591

1084

1592

case AVAHI_BROWSER_NEW:

1087

1595

the callback function is called the Avahi server will free the

1088

1596

resolver for us. */

1089

1597

1090

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

1091

name, type, domain, protocol, 0,

1092

resolve_callback, NULL) == NULL)

1598

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

1599

interface, protocol, name, type,

1600

domain, protocol, 0,

1601

resolve_callback, mc) == NULL)

1093

1602

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

1094

1603

" %s\n", name,

1095

avahi_strerror(avahi_server_errno(mc.server)));

1604

avahi_strerror(avahi_server_errno

1605

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

1096

1606

break;

1097

1607

1098

1608

case AVAHI_BROWSER_REMOVE:

1117

1627

signal_received = sig;

1118

1628

int old_errno = errno;

1119

1629

/* set main loop to exit */

1120

if(mc.simple_poll != NULL){

1121

avahi_simple_poll_quit(mc.simple_poll);

1630

if(simple_poll != NULL){

1631

avahi_simple_poll_quit(simple_poll);

1122

1632

}

1123

1633

errno = old_errno;

1124

1634

}

1125

1635

1636

__attribute__((nonnull, warn_unused_result))

1126

1637

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

1127

1638

int ret;

1128

error_t ret_errno;

1639

int old_errno;

1129

1640

1130

1641

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

1131

1642

if(s < 0){

1132

ret_errno = errno;

1643

old_errno = errno;

1133

1644

perror_plus("socket");

1134

errno = ret_errno;

1645

errno = old_errno;

1135

1646

return false;

1136

1647

}

1137

strcpy(ifr->ifr_name, ifname);

1648

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

1649

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

1138

1650

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1139

1651

if(ret == -1){

1140

1652

if(debug){

1141

ret_errno = errno;

1653

old_errno = errno;

1142

1654

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1655

errno = old_errno;

1144

1656

}

1145

1657

return false;

1146

1658

}

1147

1659

return true;

1148

1660

}

1149

1661

1662

__attribute__((nonnull, warn_unused_result))

1150

1663

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

1151

1664

1152

1665

/* Reject the loopback device */

1194

1707

* corresponds to an acceptable network device.

1195

1708

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

1196

1709

*/

1710

__attribute__((nonnull, warn_unused_result))

1197

1711

int good_interface(const struct dirent *if_entry){

1198

1712

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

1199

1713

return 0;

1217

1731

/*

1218

1732

* This function determines if a network interface is up.

1219

1733

*/

1734

__attribute__((nonnull, warn_unused_result))

1220

1735

bool interface_is_up(const char *interface){

1221

1736

struct ifreq ifr;

1222

1737

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

1233

1748

/*

1234

1749

* This function determines if a network interface is running

1235

1750

*/

1751

__attribute__((nonnull, warn_unused_result))

1236

1752

bool interface_is_running(const char *interface){

1237

1753

struct ifreq ifr;

1238

1754

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

1246

1762

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

1247

1763

}

1248

1764

1765

__attribute__((nonnull, pure, warn_unused_result))

1249

1766

int notdotentries(const struct dirent *direntry){

1250

1767

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

1251

1768

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

1258

1775

}

1259

1776

1260

1777

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

1778

__attribute__((nonnull, warn_unused_result))

1261

1779

int runnable_hook(const struct dirent *direntry){

1262

1780

int ret;

1263

1781

size_t sret;

1271

1789

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

1272

1790

"abcdefghijklmnopqrstuvwxyz"

1273

1791

"0123456789"

1274

"_-");

1792

"_.-");

1275

1793

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

1276

1794

/* Contains non-allowed characters */

1277

1795

if(debug){

1281

1799

return 0;

1282

1800

}

1283

1801

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);

1802

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

1292

1803

if(ret == -1){

1293

1804

if(debug){

1294

1805

perror_plus("Could not stat hook");

1318

1829

return 1;

1319

1830

}

1320

1831

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1832

__attribute__((nonnull, warn_unused_result))

1833

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1834

mandos_context *mc){

1322

1835

int ret;

1323

1836

struct timespec now;

1324

1837

struct timespec waited_time;

1325

1838

intmax_t block_time;

1326

1839

1327

1840

while(true){

1328

if(mc.current_server == NULL){

1329

if (debug){

1841

if(mc->current_server == NULL){

1842

if(debug){

1330

1843

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

1331

1844

" No timeout!\n");

1332

1845

}

1333

1846

ret = avahi_simple_poll_iterate(s, -1);

1334

1847

} else {

1335

if (debug){

1848

if(debug){

1336

1849

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

1337

1850

" it, or wait\n");

1338

1851

}

1345

1858

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

1346

1859

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

1347

1860

waited_time.tv_sec = (now.tv_sec

1348

- mc.current_server->last_seen.tv_sec);

1861

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

1349

1862

waited_time.tv_nsec = (now.tv_nsec

1350

- mc.current_server->last_seen.tv_nsec);

1863

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

1351

1864

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

1352

1865

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

1353

1866

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

1355

1868

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

1356

1869

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

1357

1870

1358

if (debug){

1871

if(debug){

1359

1872

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

1360

1873

block_time);

1361

1874

}

1362

1875

1363

1876

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);

1877

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

1878

mc->current_server->port,

1879

mc->current_server->if_index,

1880

mc->current_server->af, mc);

1368

1881

if(ret == 0){

1369

avahi_simple_poll_quit(mc.simple_poll);

1882

avahi_simple_poll_quit(s);

1370

1883

return 0;

1371

1884

}

1372

1885

ret = clock_gettime(CLOCK_MONOTONIC,

1373

&mc.current_server->last_seen);

1886

&mc->current_server->last_seen);

1374

1887

if(ret == -1){

1375

1888

perror_plus("clock_gettime");

1376

1889

return -1;

1377

1890

}

1378

mc.current_server = mc.current_server->next;

1891

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

1379

1892

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

1380

1893

servers, but don't block */

1381

1894

}

1383

1896

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

1384

1897

}

1385

1898

if(ret != 0){

1386

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

1899

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

1387

1900

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

1388

1901

}

1389

1902

}

1390

1903

}

1391

1904

}

1392

1905

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,

1906

__attribute__((nonnull))

1907

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

1446

1908

const float delay){

1447

struct dirent **direntries;

1909

struct dirent **direntries = NULL;

1910

if(hookdir_fd == -1){

1911

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1912

| O_CLOEXEC);

1913

if(hookdir_fd == -1){

1914

if(errno == ENOENT){

1915

if(debug){

1916

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

1917

" found\n", hookdir);

1918

}

1919

} else {

1920

perror_plus("open");

1921

}

1922

return;

1923

}

1924

}

1925

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

1926

runnable_hook, alphasort);

1927

if(numhooks == -1){

1928

perror_plus("scandir");

1929

return;

1930

}

1448

1931

struct dirent *direntry;

1449

1932

int ret;

1450

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

1451

alphasort);

1452

if(numhooks == -1){

1453

if(errno == ENOENT){

1454

if(debug){

1455

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

1456

" found\n", hookdir);

1457

}

1458

} else {

1459

perror_plus("scandir");

1933

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

1934

if(devnull == -1){

1935

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

1936

return;

1937

}

1938

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

1939

direntry = direntries[i];

1940

if(debug){

1941

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

1942

direntry->d_name);

1460

1943

}

1461

} else {

1462

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

1463

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

1464

direntry = direntries[i];

1465

char *fullname = NULL;

1466

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

1467

if(ret < 0){

1944

pid_t hook_pid = fork();

1945

if(hook_pid == 0){

1946

/* Child */

1947

/* Raise privileges */

1948

errno = raise_privileges_permanently();

1949

if(errno != 0){

1950

perror_plus("Failed to raise privileges");

1951

_exit(EX_NOPERM);

1952

}

1953

/* Set group */

1954

errno = 0;

1955

ret = setgid(0);

1956

if(ret == -1){

1957

perror_plus("setgid");

1958

_exit(EX_NOPERM);

1959

}

1960

/* Reset supplementary groups */

1961

errno = 0;

1962

ret = setgroups(0, NULL);

1963

if(ret == -1){

1964

perror_plus("setgroups");

1965

_exit(EX_NOPERM);

1966

}

1967

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

1968

if(ret == -1){

1969

perror_plus("setenv");

1970

_exit(EX_OSERR);

1971

}

1972

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

1973

if(ret == -1){

1974

perror_plus("setenv");

1975

_exit(EX_OSERR);

1976

}

1977

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

1978

if(ret == -1){

1979

perror_plus("setenv");

1980

_exit(EX_OSERR);

1981

}

1982

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

1983

if(ret == -1){

1984

perror_plus("setenv");

1985

_exit(EX_OSERR);

1986

}

1987

char *delaystring;

1988

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

1989

if(ret == -1){

1468

1990

perror_plus("asprintf");

1469

continue;

1470

}

1471

if(debug){

1472

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

1473

direntry->d_name);

1474

}

1475

pid_t hook_pid = fork();

1476

if(hook_pid == 0){

1477

/* Child */

1478

/* Raise privileges */

1479

raise_privileges_permanently();

1480

/* Set group */

1481

errno = 0;

1482

ret = setgid(0);

1483

if(ret == -1){

1484

perror_plus("setgid");

1485

}

1486

/* Reset supplementary groups */

1487

errno = 0;

1488

ret = setgroups(0, NULL);

1489

if(ret == -1){

1490

perror_plus("setgroups");

1491

}

1492

dup2(devnull, STDIN_FILENO);

1493

close(devnull);

1494

dup2(STDERR_FILENO, STDOUT_FILENO);

1495

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

1496

if(ret == -1){

1497

perror_plus("setenv");

1498

_exit(EX_OSERR);

1499

}

1500

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

1501

if(ret == -1){

1502

perror_plus("setenv");

1503

_exit(EX_OSERR);

1504

}

1505

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

1506

if(ret == -1){

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

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

1511

if(ret == -1){

1512

perror_plus("setenv");

1513

_exit(EX_OSERR);

1514

}

1515

char *delaystring;

1516

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

1517

if(ret == -1){

1518

perror_plus("asprintf");

1519

_exit(EX_OSERR);

1520

}

1521

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

1522

if(ret == -1){

1523

free(delaystring);

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1991

_exit(EX_OSERR);

1992

}

1993

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

1994

if(ret == -1){

1527

1995

free(delaystring);

1528

if(connect_to != NULL){

1529

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

1530

if(ret == -1){

1531

perror_plus("setenv");

1532

_exit(EX_OSERR);

1533

}

1534

}

1535

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

1536

perror_plus("execl");

1537

_exit(EXIT_FAILURE);

1538

}

1996

perror_plus("setenv");

1997

_exit(EX_OSERR);

1998

}

1999

free(delaystring);

2000

if(connect_to != NULL){

2001

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

2002

if(ret == -1){

2003

perror_plus("setenv");

2004

_exit(EX_OSERR);

2005

}

2006

}

2007

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

2008

direntry->d_name,

2009

O_RDONLY));

2010

if(hook_fd == -1){

2011

perror_plus("openat");

2012

_exit(EXIT_FAILURE);

2013

}

2014

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

2015

perror_plus("close");

2016

_exit(EXIT_FAILURE);

2017

}

2018

ret = dup2(devnull, STDIN_FILENO);

2019

if(ret == -1){

2020

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

2021

_exit(EX_OSERR);

2022

}

2023

ret = close(devnull);

2024

if(ret == -1){

2025

perror_plus("close");

2026

_exit(EX_OSERR);

2027

}

2028

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2029

if(ret == -1){

2030

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

2031

_exit(EX_OSERR);

2032

}

2033

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

2034

environ) == -1){

2035

perror_plus("fexecve");

2036

_exit(EXIT_FAILURE);

2037

}

2038

} else {

2039

if(hook_pid == -1){

2040

perror_plus("fork");

2041

free(direntry);

2042

continue;

2043

}

2044

int status;

2045

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

2046

perror_plus("waitpid");

2047

free(direntry);

2048

continue;

2049

}

2050

if(WIFEXITED(status)){

2051

if(WEXITSTATUS(status) != 0){

2052

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

2053

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

2054

WEXITSTATUS(status));

2055

free(direntry);

2056

continue;

2057

}

2058

} else if(WIFSIGNALED(status)){

2059

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

2060

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

2061

WTERMSIG(status));

2062

free(direntry);

2063

continue;

1539

2064

} else {

1540

int status;

1541

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

1542

perror_plus("waitpid");

1543

free(fullname);

1544

continue;

1545

}

1546

if(WIFEXITED(status)){

1547

if(WEXITSTATUS(status) != 0){

1548

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

1549

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

1550

WEXITSTATUS(status));

1551

free(fullname);

1552

continue;

1553

}

1554

} else if(WIFSIGNALED(status)){

1555

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

1556

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

1557

WTERMSIG(status));

1558

free(fullname);

1559

continue;

1560

} else {

1561

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

1562

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

1563

free(fullname);

1564

continue;

1565

}

1566

}

1567

free(fullname);

1568

if(debug){

1569

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

1570

direntry->d_name);

1571

}

1572

}

1573

close(devnull);

1574

}

1575

return true;

2065

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

2066

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

2067

free(direntry);

2068

continue;

2069

}

2070

}

2071

if(debug){

2072

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

2073

direntry->d_name);

2074

}

2075

free(direntry);

2076

}

2077

free(direntries);

2078

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

2079

perror_plus("close");

2080

} else {

2081

hookdir_fd = -1;

2082

}

2083

close(devnull);

1576

2084

}

1577

2085

1578

error_t bring_up_interface(const char *const interface,

1579

const float delay){

1580

int sd = -1;

1581

error_t old_errno = errno;

1582

error_t ret_errno = 0;

1583

int ret, ret_setflags;

2086

__attribute__((nonnull, warn_unused_result))

2087

int bring_up_interface(const char *const interface,

2088

const float delay){

2089

int old_errno = errno;

2090

int ret;

1584

2091

struct ifreq network;

1585

2092

unsigned int if_index = if_nametoindex(interface);

1586

2093

if(if_index == 0){

1595

2102

}

1596

2103

1597

2104

if(not interface_is_up(interface)){

1598

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

2105

int ret_errno = 0;

2106

int ioctl_errno = 0;

2107

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

1599

2108

ret_errno = errno;

1600

2109

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

1601

2110

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

2111

errno = old_errno;

1602

2112

return ret_errno;

1603

2113

}

1604

network.ifr_flags |= IFF_UP;

2114

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

1605

2115

1606

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1607

if(sd < 0){

2116

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

2117

if(sd == -1){

1608

2118

ret_errno = errno;

1609

2119

perror_plus("socket");

1610

2120

errno = old_errno;

1611

2121

return ret_errno;

1612

2122

}

1613

2123

1614

2124

if(quit_now){

1615

close(sd);

2125

ret = close(sd);

2126

if(ret == -1){

2127

perror_plus("close");

2128

}

1616

2129

errno = old_errno;

1617

2130

return EINTR;

1618

2131

}

1622

2135

interface);

1623

2136

}

1624

2137

1625

/* Raise priviliges */

1626

raise_privileges();

2138

/* Raise privileges */

2139

ret_errno = raise_privileges();

2140

if(ret_errno != 0){

2141

errno = ret_errno;

2142

perror_plus("Failed to raise privileges");

2143

}

1627

2144

1628

2145

#ifdef __linux__

1629

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1630

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

1631

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

1632

bool restore_loglevel = true;

1633

if(ret_linux == -1){

1634

restore_loglevel = false;

1635

perror_plus("klogctl");

2146

int ret_linux;

2147

bool restore_loglevel = false;

2148

if(ret_errno == 0){

2149

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2150

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

2151

ret_linux = klogctl(8, NULL, 5);

2152

if(ret_linux == -1){

2153

perror_plus("klogctl");

2154

} else {

2155

restore_loglevel = true;

2156

}

1636

2157

}

1637

2158

#endif /* __linux__ */

1638

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

1639

ret_errno = errno;

2159

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

2160

ioctl_errno = errno;

1640

2161

#ifdef __linux__

1641

2162

if(restore_loglevel){

1642

2163

ret_linux = klogctl(7, NULL, 0);

1646

2167

}

1647

2168

#endif /* __linux__ */

1648

2169

1649

/* Lower privileges */

1650

lower_privileges();

2170

/* If raise_privileges() succeeded above */

2171

if(ret_errno == 0){

2172

/* Lower privileges */

2173

ret_errno = lower_privileges();

2174

if(ret_errno != 0){

2175

errno = ret_errno;

2176

perror_plus("Failed to lower privileges");

2177

}

2178

}

1651

2179

1652

2180

/* Close the socket */

1653

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

2181

ret = close(sd);

1654

2182

if(ret == -1){

1655

2183

perror_plus("close");

1656

2184

}

1657

2185

1658

2186

if(ret_setflags == -1){

1659

errno = ret_errno;

2187

errno = ioctl_errno;

1660

2188

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1661

2189

errno = old_errno;

1662

return ret_errno;

2190

return ioctl_errno;

1663

2191

}

1664

2192

} else if(debug){

1665

2193

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

1668

2196

1669

2197

/* Sleep checking until interface is running.

1670

2198

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

1671

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

2199

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

1672

2200

if(interface_is_running(interface)){

1673

2201

break;

1674

2202

}

1683

2211

return 0;

1684

2212

}

1685

2213

1686

error_t take_down_interface(const char *const interface){

1687

int sd = -1;

1688

error_t old_errno = errno;

1689

error_t ret_errno = 0;

1690

int ret, ret_setflags;

2214

__attribute__((nonnull, warn_unused_result))

2215

int take_down_interface(const char *const interface){

2216

int old_errno = errno;

1691

2217

struct ifreq network;

1692

2218

unsigned int if_index = if_nametoindex(interface);

1693

2219

if(if_index == 0){

1696

2222

return ENXIO;

1697

2223

}

1698

2224

if(interface_is_up(interface)){

2225

int ret_errno = 0;

2226

int ioctl_errno = 0;

1699

2227

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

1700

2228

ret_errno = errno;

1701

2229

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

1702

2230

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

2231

errno = old_errno;

1703

2232

return ret_errno;

1704

2233

}

1705

2234

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

1706

2235

1707

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1708

if(sd < 0){

2236

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

2237

if(sd == -1){

1709

2238

ret_errno = errno;

1710

2239

perror_plus("socket");

1711

2240

errno = old_errno;

1717

2246

interface);

1718

2247

}

1719

2248

1720

/* Raise priviliges */

1721

raise_privileges();

1722

1723

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

1724

ret_errno = errno;

1725

1726

/* Lower privileges */

1727

lower_privileges();

2249

/* Raise privileges */

2250

ret_errno = raise_privileges();

2251

if(ret_errno != 0){

2252

errno = ret_errno;

2253

perror_plus("Failed to raise privileges");

2254

}

2255

2256

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

2257

ioctl_errno = errno;

2258

2259

/* If raise_privileges() succeeded above */

2260

if(ret_errno == 0){

2261

/* Lower privileges */

2262

ret_errno = lower_privileges();

2263

if(ret_errno != 0){

2264

errno = ret_errno;

2265

perror_plus("Failed to lower privileges");

2266

}

2267

}

1728

2268

1729

2269

/* Close the socket */

1730

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

2270

int ret = close(sd);

1731

2271

if(ret == -1){

1732

2272

perror_plus("close");

1733

2273

}

1734

2274

1735

2275

if(ret_setflags == -1){

1736

errno = ret_errno;

2276

errno = ioctl_errno;

1737

2277

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1738

2278

errno = old_errno;

1739

return ret_errno;

2279

return ioctl_errno;

1740

2280

}

1741

2281

} else if(debug){

1742

2282

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

1748

2288

}

1749

2289

1750

2290

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

2291

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

2292

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

2293

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

2294

.current_server = NULL, .interfaces = NULL,

2295

.interfaces_size = 0 };

1751

2296

AvahiSServiceBrowser *sb = NULL;

1752

2297

error_t ret_errno;

1753

2298

int ret;

1754

2299

intmax_t tmpmax;

1755

2300

char *tmp;

1756

2301

int exitcode = EXIT_SUCCESS;

1757

char *interfaces = NULL;

1758

size_t interfaces_size = 0;

1759

2302

char *interfaces_to_take_down = NULL;

1760

2303

size_t interfaces_to_take_down_size = 0;

1761

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

1762

bool tempdir_created = false;

2304

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

2305

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

2306

char *tempdir = NULL;

1763

2307

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1764

2308

const char *seckey = PATHDIR "/" SECKEY;

1765

2309

const char *pubkey = PATHDIR "/" PUBKEY;

2310

const char *dh_params_file = NULL;

1766

2311

char *interfaces_hooks = NULL;

1767

size_t interfaces_hooks_size = 0;

1768

2312

1769

2313

bool gnutls_initialized = false;

1770

2314

bool gpgme_initialized = false;

1822

2366

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

1823

2367

" Diffie-Hellman key exchange",

1824

2368

.group = 2 },

2369

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

2370

.arg = "FILE",

2371

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

2372

" for the Diffie-Hellman key exchange",

2373

.group = 2 },

1825

2374

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

1826

2375

.arg = "STRING",

1827

2376

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

1861

2410

connect_to = arg;

1862

2411

break;

1863

2412

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

1864

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

1865

(int)',');

2413

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

2414

arg, (int)',');

1866

2415

if(ret_errno != 0){

1867

2416

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

1868

2417

}

1882

2431

}

1883

2432

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

1884

2433

break;

2434

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

2435

dh_params_file = arg;

2436

break;

1885

2437

case 130: /* --priority */

1886

2438

mc.priority = arg;

1887

2439

break;

1927

2479

.args_doc = "",

1928

2480

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

1929

2481

" passwords from a Mandos server" };

1930

ret = argp_parse(&argp, argc, argv,

1931

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1932

switch(ret){

2482

ret_errno = argp_parse(&argp, argc, argv,

2483

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2484

switch(ret_errno){

1933

2485

case 0:

1934

2486

break;

1935

2487

case ENOMEM:

1936

2488

default:

1937

errno = ret;

2489

errno = ret_errno;

1938

2490

perror_plus("argp_parse");

1939

2491

exitcode = EX_OSERR;

1940

2492

goto end;

1943

2495

goto end;

1944

2496

}

1945

2497

}

1946

2498

1947

2499

{

1948

2500

/* Work around Debian bug #633582:

1949

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

2501

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

1950

2502

1951

/* Re-raise priviliges */

1952

if(raise_privileges() == 0){

2503

/* Re-raise privileges */

2504

ret = raise_privileges();

2505

if(ret != 0){

2506

errno = ret;

2507

perror_plus("Failed to raise privileges");

2508

} else {

1953

2509

struct stat st;

1954

2510

1955

2511

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

1969

2525

}

1970

2526

}

1971

2527

}

1972

TEMP_FAILURE_RETRY(close(seckey_fd));

2528

close(seckey_fd);

1973

2529

}

1974

2530

}

1975

2531

1976

2532

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

1977

2533

int pubkey_fd = open(pubkey, O_RDONLY);

1978

2534

if(pubkey_fd == -1){

1990

2546

}

1991

2547

}

1992

2548

}

1993

TEMP_FAILURE_RETRY(close(pubkey_fd));

1994

}

1995

}

1996

2549

close(pubkey_fd);

2550

}

2551

}

2552

2553

if(dh_params_file != NULL

2554

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

2555

int dhparams_fd = open(dh_params_file, O_RDONLY);

2556

if(dhparams_fd == -1){

2557

perror_plus("open");

2558

} else {

2559

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

2560

if(ret == -1){

2561

perror_plus("fstat");

2562

} else {

2563

if(S_ISREG(st.st_mode)

2564

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

2565

ret = fchown(dhparams_fd, uid, gid);

2566

if(ret == -1){

2567

perror_plus("fchown");

2568

}

2569

}

2570

}

2571

close(dhparams_fd);

2572

}

2573

}

2574

1997

2575

/* Lower privileges */

1998

errno = 0;

1999

ret = seteuid(uid);

2000

if(ret == -1){

2001

perror_plus("seteuid");

2576

ret = lower_privileges();

2577

if(ret != 0){

2578

errno = ret;

2579

perror_plus("Failed to lower privileges");

2002

2580

}

2003

2581

}

2004

2582

}

2005

2583

2006

/* Remove empty interface names */

2584

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

2007

2585

{

2008

2586

char *interface = NULL;

2009

while((interface = argz_next(interfaces, interfaces_size,

2587

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

2010

2588

interface))){

2011

if(if_nametoindex(interface) == 0){

2012

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

2589

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

2590

and if_nametoindex(interface) == 0){

2591

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

2013

2592

fprintf_plus(stderr, "Not using nonexisting interface"

2014

2593

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

2015

2594

}

2016

argz_delete(&interfaces, &interfaces_size, interface);

2595

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

2017

2596

interface = NULL;

2018

2597

}

2019

2598

}

2021

2600

2022

2601

/* Run network hooks */

2023

2602

{

2024

2025

if(interfaces != NULL){

2026

interfaces_hooks = malloc(interfaces_size);

2603

if(mc.interfaces != NULL){

2604

interfaces_hooks = malloc(mc.interfaces_size);

2027

2605

if(interfaces_hooks == NULL){

2028

2606

perror_plus("malloc");

2029

2607

goto end;

2030

2608

}

2031

memcpy(interfaces_hooks, interfaces, interfaces_size);

2032

interfaces_hooks_size = interfaces_size;

2033

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2034

(int)',');

2035

}

2036

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

2037

interfaces_hooks : "", delay)){

2038

goto end;

2039

}

2609

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

2610

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

2611

}

2612

run_network_hooks("start", interfaces_hooks != NULL ?

2613

interfaces_hooks : "", delay);

2040

2614

}

2041

2615

2042

2616

if(not debug){

2047

2621

from the signal handler */

2048

2622

/* Initialize the pseudo-RNG for Avahi */

2049

2623

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

2050

mc.simple_poll = avahi_simple_poll_new();

2051

if(mc.simple_poll == NULL){

2624

simple_poll = avahi_simple_poll_new();

2625

if(simple_poll == NULL){

2052

2626

fprintf_plus(stderr,

2053

2627

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

2054

2628

exitcode = EX_UNAVAILABLE;

2119

2693

}

2120

2694

2121

2695

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

2122

if(interfaces == NULL){

2123

struct dirent **direntries;

2696

if(mc.interfaces == NULL){

2697

struct dirent **direntries = NULL;

2124

2698

/* Look for any good interfaces */

2125

2699

ret = scandir(sys_class_net, &direntries, good_interface,

2126

2700

alphasort);

2127

2701

if(ret >= 1){

2128

2702

/* Add all found interfaces to interfaces list */

2129

2703

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

2130

ret_errno = argz_add(&interfaces, &interfaces_size,

2704

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

2131

2705

direntries[i]->d_name);

2132

2706

if(ret_errno != 0){

2707

errno = ret_errno;

2133

2708

perror_plus("argz_add");

2709

free(direntries[i]);

2134

2710

continue;

2135

2711

}

2136

2712

if(debug){

2137

2713

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

2138

2714

direntries[i]->d_name);

2139

2715

}

2716

free(direntries[i]);

2140

2717

}

2141

2718

free(direntries);

2142

2719

} else {

2143

free(direntries);

2720

if(ret == 0){

2721

free(direntries);

2722

}

2144

2723

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

2145

2724

exitcode = EXIT_FAILURE;

2146

2725

goto end;

2147

2726

}

2148

2727

}

2149

2728

2150

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

2151

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

2152

if(debug){

2153

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

2154

interfaces);

2155

}

2156

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2157

}

2158

2159

/* Bring up interfaces which are down */

2160

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

2161

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

2729

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

2730

{

2162

2731

char *interface = NULL;

2163

while((interface = argz_next(interfaces, interfaces_size,

2732

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

2164

2733

interface))){

2734

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

2735

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

2736

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

2737

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

2738

interface);

2739

interface = NULL;

2740

while((interface = argz_next(mc.interfaces,

2741

mc.interfaces_size, interface))){

2742

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

2743

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

2744

interface);

2745

interface = NULL;

2746

}

2747

}

2748

break;

2749

}

2165

2750

bool interface_was_up = interface_is_up(interface);

2166

ret = bring_up_interface(interface, delay);

2751

errno = bring_up_interface(interface, delay);

2167

2752

if(not interface_was_up){

2168

if(ret != 0){

2169

errno = ret;

2170

perror_plus("Failed to bring up interface");

2753

if(errno != 0){

2754

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

2755

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

2171

2756

} else {

2172

ret_errno = argz_add(&interfaces_to_take_down,

2173

&interfaces_to_take_down_size,

2174

interface);

2757

errno = argz_add(&interfaces_to_take_down,

2758

&interfaces_to_take_down_size,

2759

interface);

2760

if(errno != 0){

2761

perror_plus("argz_add");

2762

}

2175

2763

}

2176

2764

}

2177

2765

}

2178

free(interfaces);

2179

interfaces = NULL;

2180

interfaces_size = 0;

2181

2766

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

2182

2767

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

2183

2768

}

2184

2769

}

2185

2770

2771

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

2772

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

2773

if(debug){

2774

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

2775

mc.interfaces);

2776

}

2777

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

2778

}

2779

2186

2780

if(quit_now){

2187

2781

goto end;

2188

2782

}

2189

2783

2190

ret = init_gnutls_global(pubkey, seckey);

2784

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

2191

2785

if(ret == -1){

2192

2786

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

2193

2787

exitcode = EX_UNAVAILABLE;

2200

2794

goto end;

2201

2795

}

2202

2796

2203

if(mkdtemp(tempdir) == NULL){

2797

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

2798

tempdir = mkdtemp(run_tempdir);

2799

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

2800

if(debug){

2801

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

2802

run_tempdir, old_tempdir);

2803

}

2804

tempdir = mkdtemp(old_tempdir);

2805

}

2806

if(tempdir == NULL){

2204

2807

perror_plus("mkdtemp");

2205

2808

goto end;

2206

2809

}

2207

tempdir_created = true;

2208

2810

2209

2811

if(quit_now){

2210

2812

goto end;

2211

2813

}

2212

2814

2213

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

2815

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

2214

2816

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

2215

2817

exitcode = EX_UNAVAILABLE;

2216

2818

goto end;

2246

2848

exitcode = EX_USAGE;

2247

2849

goto end;

2248

2850

}

2249

2851

2250

2852

if(quit_now){

2251

2853

goto end;

2252

2854

}

2273

2875

}

2274

2876

2275

2877

while(not quit_now){

2276

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

2878

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

2879

&mc);

2277

2880

if(quit_now or ret == 0){

2278

2881

break;

2279

2882

}

2281

2884

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

2282

2885

(int)retry_interval);

2283

2886

}

2284

sleep((int)retry_interval);

2887

sleep((unsigned int)retry_interval);

2285

2888

}

2286

2889

2287

if (not quit_now){

2890

if(not quit_now){

2288

2891

exitcode = EXIT_SUCCESS;

2289

2892

}

2290

2893

2305

2908

config.publish_domain = 0;

2306

2909

2307

2910

/* Allocate a new server */

2308

mc.server = avahi_server_new(avahi_simple_poll_get

2309

(mc.simple_poll), &config, NULL,

2310

NULL, &ret_errno);

2911

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2912

&config, NULL, NULL, &ret);

2311

2913

2312

2914

/* Free the Avahi configuration data */

2313

2915

avahi_server_config_free(&config);

2316

2918

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

2317

2919

if(mc.server == NULL){

2318

2920

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

2319

avahi_strerror(ret_errno));

2921

avahi_strerror(ret));

2320

2922

exitcode = EX_UNAVAILABLE;

2321

2923

goto end;

2322

2924

}

2328

2930

/* Create the Avahi service browser */

2329

2931

sb = avahi_s_service_browser_new(mc.server, if_index,

2330

2932

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2331

NULL, 0, browse_callback, NULL);

2933

NULL, 0, browse_callback,

2934

(void *)&mc);

2332

2935

if(sb == NULL){

2333

2936

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

2334

2937

avahi_strerror(avahi_server_errno(mc.server)));

2345

2948

if(debug){

2346

2949

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

2347

2950

}

2348

2349

ret = avahi_loop_with_timeout(mc.simple_poll,

2350

(int)(retry_interval * 1000));

2951

2952

ret = avahi_loop_with_timeout(simple_poll,

2953

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

2351

2954

if(debug){

2352

2955

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

2353

2956

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

2356

2959

end:

2357

2960

2358

2961

if(debug){

2359

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

2962

if(signal_received){

2963

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

2964

argv[0], signal_received,

2965

strsignal(signal_received));

2966

} else {

2967

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

2968

}

2360

2969

}

2361

2970

2362

2971

/* Cleanup things */

2972

free(mc.interfaces);

2973

2363

2974

if(sb != NULL)

2364

2975

avahi_s_service_browser_free(sb);

2365

2976

2366

2977

if(mc.server != NULL)

2367

2978

avahi_server_free(mc.server);

2368

2979

2369

if(mc.simple_poll != NULL)

2370

avahi_simple_poll_free(mc.simple_poll);

2980

if(simple_poll != NULL)

2981

avahi_simple_poll_free(simple_poll);

2371

2982

2372

2983

if(gnutls_initialized){

2373

2984

gnutls_certificate_free_credentials(mc.cred);

2374

gnutls_global_deinit();

2375

2985

gnutls_dh_params_deinit(mc.dh_params);

2376

2986

}

2377

2987

2385

2995

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

2386

2996

while(mc.current_server != NULL){

2387

2997

server *next = mc.current_server->next;

2998

#ifdef __GNUC__

2999

#pragma GCC diagnostic push

3000

#pragma GCC diagnostic ignored "-Wcast-qual"

3001

#endif

3002

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

3003

#ifdef __GNUC__

3004

#pragma GCC diagnostic pop

3005

#endif

2388

3006

free(mc.current_server);

2389

3007

mc.current_server = next;

2390

3008

}

2391

3009

}

2392

3010

2393

/* Re-raise priviliges */

3011

/* Re-raise privileges */

2394

3012

{

2395

raise_privileges();

2396

2397

/* Run network hooks */

2398

run_network_hooks("stop", interfaces_hooks != NULL ?

2399

interfaces_hooks : "", delay);

2400

2401

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

2402

{

2403

char *interface = NULL;

2404

while((interface=argz_next(interfaces_to_take_down,

2405

interfaces_to_take_down_size,

2406

interface))){

2407

ret_errno = take_down_interface(interface);

2408

if(ret_errno != 0){

2409

errno = ret_errno;

2410

perror_plus("Failed to take down interface");

2411

}

2412

}

2413

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

2414

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

2415

" down\n");

2416

}

2417

}

2418

2419

lower_privileges_permanently();

3013

ret = raise_privileges();

3014

if(ret != 0){

3015

errno = ret;

3016

perror_plus("Failed to raise privileges");

3017

} else {

3018

3019

/* Run network hooks */

3020

run_network_hooks("stop", interfaces_hooks != NULL ?

3021

interfaces_hooks : "", delay);

3022

3023

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

3024

{

3025

char *interface = NULL;

3026

while((interface = argz_next(interfaces_to_take_down,

3027

interfaces_to_take_down_size,

3028

interface))){

3029

ret = take_down_interface(interface);

3030

if(ret != 0){

3031

errno = ret;

3032

perror_plus("Failed to take down interface");

3033

}

3034

}

3035

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

3036

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

3037

" down\n");

3038

}

3039

}

3040

}

3041

3042

ret = lower_privileges_permanently();

3043

if(ret != 0){

3044

errno = ret;

3045

perror_plus("Failed to lower privileges permanently");

3046

}

2420

3047

}

2421

3048

2422

3049

free(interfaces_to_take_down);

2423

3050

free(interfaces_hooks);

2424

3051

3052

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

3053

uintmax_t level){

3054

struct dirent **direntries = NULL;

3055

int dret;

3056

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

3057

O_RDONLY

3058

| O_NOFOLLOW

3059

| O_DIRECTORY

3060

| O_PATH));

3061

if(dir_fd == -1){

3062

perror_plus("open");

3063

}

3064

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

3065

notdotentries, alphasort);

3066

if(numentries >= 0){

3067

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

3068

if(debug){

3069

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

3070

dirname, direntries[i]->d_name);

3071

}

3072

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

3073

if(dret == -1){

3074

if(errno == EISDIR){

3075

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

3076

AT_REMOVEDIR);

3077

}

3078

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

3079

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

3080

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

3081

/* Recurse only in this special case */

3082

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

3083

dret = 0;

3084

}

3085

if(dret == -1){

3086

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

3087

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

3088

}

3089

}

3090

free(direntries[i]);

3091

}

3092

3093

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

3094

free(direntries);

3095

if(numentries == -1){

3096

perror_plus("scandirat");

3097

}

3098

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3099

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

3100

perror_plus("rmdir");

3101

}

3102

} else {

3103

perror_plus("scandirat");

3104

}

3105

close(dir_fd);

3106

}

3107

2425

3108

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

2426

if(tempdir_created){

2427

struct dirent **direntries = NULL;

2428

struct dirent *direntry = NULL;

2429

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

2430

alphasort);

2431

if (numentries > 0){

2432

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

2433

direntry = direntries[i];

2434

char *fullname = NULL;

2435

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

2436

direntry->d_name);

2437

if(ret < 0){

2438

perror_plus("asprintf");

2439

continue;

2440

}

2441

ret = remove(fullname);

2442

if(ret == -1){

2443

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

2444

strerror(errno));

2445

}

2446

free(fullname);

2447

}

2448

}

2449

2450

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

2451

free(direntries);

2452

if (numentries == -1){

2453

perror_plus("scandir");

2454

}

2455

ret = rmdir(tempdir);

2456

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

2457

perror_plus("rmdir");

2458

}

3109

if(tempdir != NULL){

3110

clean_dir_at(-1, tempdir, 0);

2459

3111

}

2460

3112

2461

3113

if(quit_now){