/mandos/release : revision 237.7.354

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

41

42

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

43

stdout, ferror(), remove() */

44

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

43

stdout, ferror() */

44

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

45

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

46

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

47

strtof(), abort() */

48

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

49

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

50

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

49

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

50

asprintf(), strncpy() */

51

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

52

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

53

sockaddr_in6, PF_INET6,

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect() */

59

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

61

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

61

62

*/

62

63

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

63

64

strtoimax() */

64

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

65

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

66

program_invocation_short_name */

67

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

73

*/

74

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

75

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

76

setgid(), pause() */

77

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

76

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

77

unlinkat() */

78

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

78

79

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

79

80

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

80

81

argp_state, struct argp,

87

88

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

89

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

89

90

WEXITSTATUS(), WTERMSIG() */

91

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

92

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

93

argz_delete(), argz_append(),

94

argz_stringify(), argz_add(),

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

90

98

91

99

#ifdef __linux__

92

100

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

134

142

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

135

143

char *connect_to = NULL;

136

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

137

148

138

149

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

139

150

typedef struct server{

140

151

const char *ip;

141

uint16_t port;

152

in_port_t port;

142

153

AvahiIfIndex if_index;

143

154

int af;

144

155

struct timespec last_seen;

148

159

149

160

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

150

161

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

162

AvahiServer *server;

153

163

gnutls_certificate_credentials_t cred;

154

164

unsigned int dh_bits;

156

166

const char *priority;

157

167

gpgme_ctx_t ctx;

158

168

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

159

171

} mandos_context;

160

172

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

166

175

167

176

sig_atomic_t quit_now = 0;

168

177

int signal_received = 0;

169

178

170

179

/* Function to use when printing errors */

171

180

void perror_plus(const char *print_text){

181

int e = errno;

172

182

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

173

183

program_invocation_short_name);

184

errno = e;

174

185

perror(print_text);

175

186

}

176

187

188

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

177

189

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

178

190

va_list ap;

179

191

va_start (ap, format);

180

192

181

193

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

182

194

program_invocation_short_name));

183

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

195

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

184

196

}

185

197

186

198

/*

188

200

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

189

201

* "buffer_length" is how much is already used.

190

202

*/

203

__attribute__((nonnull, warn_unused_result))

191

204

size_t incbuffer(char **buffer, size_t buffer_length,

192

205

size_t buffer_capacity){

193

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

194

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

195

if(buffer == NULL){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

196

213

return 0;

197

214

}

215

*buffer = new_buf;

198

216

buffer_capacity += BUFFER_SIZE;

199

217

}

200

218

return buffer_capacity;

201

219

}

202

220

203

221

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

204

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

205

int af){

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

206

225

int ret;

207

226

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

208

227

if(new_server == NULL){

209

228

perror_plus("malloc");

210

return -1;

229

return false;

211

230

}

212

231

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

213

232

.port = port,

215

234

.af = af };

216

235

if(new_server->ip == NULL){

217

236

perror_plus("strdup");

218

return -1;

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

219

253

}

220

254

/* Special case of first server */

221

if (mc.current_server == NULL){

255

if(*current_server == NULL){

222

256

new_server->next = new_server;

223

257

new_server->prev = new_server;

224

mc.current_server = new_server;

225

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

258

*current_server = new_server;

226

259

} else {

227

new_server->next = mc.current_server;

228

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

260

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

261

new_server->next = *current_server;

262

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

229

263

new_server->prev->next = new_server;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

264

(*current_server)->prev = new_server;

265

}

266

return true;

238

267

}

239

268

240

269

/*

241

270

* Initialize GPGME.

242

271

*/

243

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

244

const char *tempdir){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

245

277

gpgme_error_t rc;

246

278

gpgme_engine_info_t engine_info;

247

279

248

249

280

/*

250

281

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

251

282

*/

252

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

253

284

int ret;

254

285

int fd;

255

286

gpgme_data_t pgp_data;

267

298

return false;

268

299

}

269

300

270

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

271

302

if(rc != GPG_ERR_NO_ERROR){

272

303

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

273

304

gpgme_strsource(rc), gpgme_strerror(rc));

274

305

return false;

275

306

}

276

307

277

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

308

ret = close(fd);

278

309

if(ret == -1){

279

310

perror_plus("close");

280

311

}

317

348

}

318

349

319

350

/* Create new GPGME "context" */

320

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

351

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

321

352

if(rc != GPG_ERR_NO_ERROR){

322

353

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

323

354

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

336

367

* Decrypt OpenPGP data.

337

368

* Returns -1 on error

338

369

*/

370

__attribute__((nonnull, warn_unused_result))

339

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

372

size_t crypto_size,

341

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

342

375

gpgme_data_t dh_crypto, dh_plain;

343

376

gpgme_error_t rc;

344

377

ssize_t ret;

370

403

371

404

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

372

405

data buffer */

373

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

406

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

374

407

if(rc != GPG_ERR_NO_ERROR){

375

408

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

376

409

gpgme_strsource(rc), gpgme_strerror(rc));

377

410

plaintext_length = -1;

378

411

if(debug){

379

412

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

381

414

if(result == NULL){

382

415

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

383

416

} else {

460

493

return plaintext_length;

461

494

}

462

495

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

466

if(ret == NULL)

467

ret = "(unknown)";

468

return ret;

496

__attribute__((warn_unused_result, const))

497

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

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

__attribute__((warn_unused_result))

504

static const char *safer_gnutls_strerror(int value){

505

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

469

507

}

470

508

471

509

/* GnuTLS log function callback */

510

__attribute__((nonnull))

472

511

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

473

512

const char* string){

474

513

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

475

514

}

476

515

516

__attribute__((nonnull, warn_unused_result))

477

517

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

518

const char *seckeyfilename,

519

const char *dhparamsfilename,

520

mandos_context *mc){

479

521

int ret;

522

unsigned int uret;

480

523

481

524

if(debug){

482

525

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

498

541

}

499

542

500

543

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

544

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

545

if(ret != GNUTLS_E_SUCCESS){

503

546

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

504

547

safer_gnutls_strerror(ret));

514

557

}

515

558

516

559

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

560

(mc->cred, pubkeyfilename, seckeyfilename,

518

561

GNUTLS_OPENPGP_FMT_BASE64);

519

562

if(ret != GNUTLS_E_SUCCESS){

520

563

fprintf_plus(stderr,

526

569

}

527

570

528

571

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

572

ret = gnutls_dh_params_init(&mc->dh_params);

530

573

if(ret != GNUTLS_E_SUCCESS){

531

574

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

575

" initialization: %s\n",

533

576

safer_gnutls_strerror(ret));

534

577

goto globalfail;

535

578

}

536

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

537

if(ret != GNUTLS_E_SUCCESS){

538

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

539

safer_gnutls_strerror(ret));

540

goto globalfail;

541

}

542

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

579

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

580

if(dhparamsfilename != NULL){

581

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

582

do {

583

int dhpfile = open(dhparamsfilename, O_RDONLY);

584

if(dhpfile == -1){

585

perror_plus("open");

586

dhparamsfilename = NULL;

587

break;

588

}

589

size_t params_capacity = 0;

590

while(true){

591

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

592

(size_t)params.size,

593

(size_t)params_capacity);

594

if(params_capacity == 0){

595

perror_plus("incbuffer");

596

free(params.data);

597

params.data = NULL;

598

dhparamsfilename = NULL;

599

break;

600

}

601

ssize_t bytes_read = read(dhpfile,

602

params.data + params.size,

603

BUFFER_SIZE);

604

/* EOF */

605

if(bytes_read == 0){

606

break;

607

}

608

/* check bytes_read for failure */

609

if(bytes_read < 0){

610

perror_plus("read");

611

free(params.data);

612

params.data = NULL;

613

dhparamsfilename = NULL;

614

break;

615

}

616

params.size += (unsigned int)bytes_read;

617

}

618

if(params.data == NULL){

619

dhparamsfilename = NULL;

620

}

621

if(dhparamsfilename == NULL){

622

break;

623

}

624

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

625

GNUTLS_X509_FMT_PEM);

626

if(ret != GNUTLS_E_SUCCESS){

627

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

628

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

629

safer_gnutls_strerror(ret));

630

dhparamsfilename = NULL;

631

}

632

} while(false);

633

}

634

if(dhparamsfilename == NULL){

635

if(mc->dh_bits == 0){

636

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

637

/* Try to read the private key file */

638

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

639

do {

640

int secfile = open(seckeyfilename, O_RDONLY);

641

if(secfile == -1){

642

perror_plus("open");

643

break;

644

}

645

size_t buffer_capacity = 0;

646

while(true){

647

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

648

(size_t)buffer.size,

649

(size_t)buffer_capacity);

650

if(buffer_capacity == 0){

651

perror_plus("incbuffer");

652

free(buffer.data);

653

buffer.data = NULL;

654

break;

655

}

656

ssize_t bytes_read = read(secfile,

657

buffer.data + buffer.size,

658

BUFFER_SIZE);

659

/* EOF */

660

if(bytes_read == 0){

661

break;

662

}

663

/* check bytes_read for failure */

664

if(bytes_read < 0){

665

perror_plus("read");

666

free(buffer.data);

667

buffer.data = NULL;

668

break;

669

}

670

buffer.size += (unsigned int)bytes_read;

671

}

672

close(secfile);

673

} while(false);

674

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

675

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

676

if(buffer.data != NULL){

677

{

678

gnutls_openpgp_privkey_t privkey = NULL;

679

ret = gnutls_openpgp_privkey_init(&privkey);

680

if(ret != GNUTLS_E_SUCCESS){

681

fprintf_plus(stderr, "Error initializing OpenPGP key"

682

" structure: %s",

683

safer_gnutls_strerror(ret));

684

free(buffer.data);

685

buffer.data = NULL;

686

} else {

687

ret = gnutls_openpgp_privkey_import

688

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

689

if(ret != GNUTLS_E_SUCCESS){

690

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

691

safer_gnutls_strerror(ret));

692

privkey = NULL;

693

}

694

free(buffer.data);

695

buffer.data = NULL;

696

if(privkey != NULL){

697

/* Use private key to suggest an appropriate

698

sec_param */

699

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

700

gnutls_openpgp_privkey_deinit(privkey);

701

if(debug){

702

fprintf_plus(stderr, "This OpenPGP key implies using"

703

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

704

safe_string(gnutls_sec_param_get_name

705

(sec_param)));

706

}

707

}

708

}

709

}

710

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

711

/* Err on the side of caution */

712

sec_param = GNUTLS_SEC_PARAM_ULTRA;

713

if(debug){

714

fprintf_plus(stderr, "Falling back to security parameter"

715

" \"%s\"\n",

716

safe_string(gnutls_sec_param_get_name

717

(sec_param)));

718

}

719

}

720

}

721

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

722

if(uret != 0){

723

mc->dh_bits = uret;

724

if(debug){

725

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

726

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

727

safe_string(gnutls_sec_param_get_name

728

(sec_param)),

729

mc->dh_bits);

730

}

731

} else {

732

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

733

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

734

safe_string(gnutls_sec_param_get_name

735

(sec_param)),

736

safer_gnutls_strerror(ret));

737

goto globalfail;

738

}

739

} else if(debug){

740

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

741

mc->dh_bits);

742

}

743

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

744

if(ret != GNUTLS_E_SUCCESS){

745

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

746

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

747

safer_gnutls_strerror(ret));

748

goto globalfail;

749

}

750

}

751

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

544

752

545

753

return 0;

546

754

547

755

globalfail:

548

756

549

gnutls_certificate_free_credentials(mc.cred);

757

gnutls_certificate_free_credentials(mc->cred);

550

758

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

759

gnutls_dh_params_deinit(mc->dh_params);

552

760

return -1;

553

761

}

554

762

555

static int init_gnutls_session(gnutls_session_t *session){

763

__attribute__((nonnull, warn_unused_result))

764

static int init_gnutls_session(gnutls_session_t *session,

765

mandos_context *mc){

556

766

int ret;

557

767

/* GnuTLS session creation */

558

768

do {

570

780

{

571

781

const char *err;

572

782

do {

573

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

783

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

574

784

if(quit_now){

575

785

gnutls_deinit(*session);

576

786

return -1;

587

797

588

798

do {

589

799

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

800

mc->cred);

591

801

if(quit_now){

592

802

gnutls_deinit(*session);

593

803

return -1;

603

813

/* ignore client certificate if any. */

604

814

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

815

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

816

return 0;

609

817

}

610

818

612

820

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

613

821

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

614

822

823

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

824

__attribute__((warn_unused_result))

825

error_t raise_privileges(void){

826

error_t old_errno = errno;

827

error_t ret_errno = 0;

828

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

829

ret_errno = errno;

830

}

831

errno = old_errno;

832

return ret_errno;

833

}

834

835

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

836

__attribute__((warn_unused_result))

837

error_t raise_privileges_permanently(void){

838

error_t old_errno = errno;

839

error_t ret_errno = raise_privileges();

840

if(ret_errno != 0){

841

errno = old_errno;

842

return ret_errno;

843

}

844

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

845

ret_errno = errno;

846

}

847

errno = old_errno;

848

return ret_errno;

849

}

850

851

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

852

__attribute__((warn_unused_result))

853

error_t lower_privileges(void){

854

error_t old_errno = errno;

855

error_t ret_errno = 0;

856

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

857

ret_errno = errno;

858

}

859

errno = old_errno;

860

return ret_errno;

861

}

862

863

/* Lower privileges permanently */

864

__attribute__((warn_unused_result))

865

error_t lower_privileges_permanently(void){

866

error_t old_errno = errno;

867

error_t ret_errno = 0;

868

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

869

ret_errno = errno;

870

}

871

errno = old_errno;

872

return ret_errno;

873

}

874

875

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

876

__attribute__((nonnull, warn_unused_result))

877

static bool add_delete_local_route(const bool add,

878

const char *address,

879

AvahiIfIndex if_index){

880

int ret;

881

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

882

char add_arg[] = "add";

883

char delete_arg[] = "delete";

884

char debug_flag[] = "--debug";

885

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

886

if(pluginhelperdir == NULL){

887

if(debug){

888

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

889

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

890

}

891

return false;

892

}

893

894

char interface[IF_NAMESIZE];

895

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

896

perror_plus("if_indextoname");

897

return false;

898

}

899

900

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

901

if(devnull == -1){

902

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

903

return false;

904

}

905

pid_t pid = fork();

906

if(pid == 0){

907

/* Child */

908

/* Raise privileges */

909

errno = raise_privileges_permanently();

910

if(errno != 0){

911

perror_plus("Failed to raise privileges");

912

/* _exit(EX_NOPERM); */

913

} else {

914

/* Set group */

915

errno = 0;

916

ret = setgid(0);

917

if(ret == -1){

918

perror_plus("setgid");

919

_exit(EX_NOPERM);

920

}

921

/* Reset supplementary groups */

922

errno = 0;

923

ret = setgroups(0, NULL);

924

if(ret == -1){

925

perror_plus("setgroups");

926

_exit(EX_NOPERM);

927

}

928

}

929

ret = dup2(devnull, STDIN_FILENO);

930

if(ret == -1){

931

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

932

_exit(EX_OSERR);

933

}

934

ret = close(devnull);

935

if(ret == -1){

936

perror_plus("close");

937

_exit(EX_OSERR);

938

}

939

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

940

if(ret == -1){

941

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

942

_exit(EX_OSERR);

943

}

944

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

945

O_RDONLY

946

| O_DIRECTORY

947

| O_PATH

948

| O_CLOEXEC));

949

if(helperdir_fd == -1){

950

perror_plus("open");

951

_exit(EX_UNAVAILABLE);

952

}

953

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

954

helper, O_RDONLY));

955

if(helper_fd == -1){

956

perror_plus("openat");

957

close(helperdir_fd);

958

_exit(EX_UNAVAILABLE);

959

}

960

close(helperdir_fd);

961

#ifdef __GNUC__

962

#pragma GCC diagnostic push

963

#pragma GCC diagnostic ignored "-Wcast-qual"

964

#endif

965

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

966

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

967

interface, debug ? debug_flag : NULL, NULL },

968

environ) == -1){

969

#ifdef __GNUC__

970

#pragma GCC diagnostic pop

971

#endif

972

perror_plus("fexecve");

973

_exit(EXIT_FAILURE);

974

}

975

}

976

if(pid == -1){

977

perror_plus("fork");

978

return false;

979

}

980

int status;

981

pid_t pret = -1;

982

errno = 0;

983

do {

984

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

985

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

986

int errno_raising = 0;

987

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

988

errno_raising = errno;

989

perror_plus("Failed to raise privileges in order to"

990

" kill helper program");

991

}

992

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

993

perror_plus("kill");

994

}

995

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

996

perror_plus("Failed to lower privileges after killing"

997

" helper program");

998

}

999

return false;

1000

}

1001

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

1002

if(pret == -1){

1003

perror_plus("waitpid");

1004

return false;

1005

}

1006

if(WIFEXITED(status)){

1007

if(WEXITSTATUS(status) != 0){

1008

fprintf_plus(stderr, "Error: iprouteadddel exited"

1009

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

1010

return false;

1011

}

1012

return true;

1013

}

1014

if(WIFSIGNALED(status)){

1015

fprintf_plus(stderr, "Error: iprouteadddel died by"

1016

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

1017

return false;

1018

}

1019

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

1020

return false;

1021

}

1022

1023

__attribute__((nonnull, warn_unused_result))

1024

static bool add_local_route(const char *address,

1025

AvahiIfIndex if_index){

1026

if(debug){

1027

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

1028

}

1029

return add_delete_local_route(true, address, if_index);

1030

}

1031

1032

__attribute__((nonnull, warn_unused_result))

1033

static bool delete_local_route(const char *address,

1034

AvahiIfIndex if_index){

1035

if(debug){

1036

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

1037

}

1038

return add_delete_local_route(false, address, if_index);

1039

}

1040

615

1041

/* Called when a Mandos server is found */

616

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

1042

__attribute__((nonnull, warn_unused_result))

1043

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

617

1044

AvahiIfIndex if_index,

618

int af){

1045

int af, mandos_context *mc){

619

1046

int ret, tcp_sd = -1;

620

1047

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1048

struct sockaddr_storage to;

625

1049

char *buffer = NULL;

626

1050

char *decrypted_buffer = NULL;

627

1051

size_t buffer_length = 0;

630

1054

int retval = -1;

631

1055

gnutls_session_t session;

632

1056

int pf; /* Protocol family */

1057

bool route_added = false;

633

1058

634

1059

errno = 0;

635

1060

651

1076

return -1;

652

1077

}

653

1078

654

ret = init_gnutls_session(&session);

1079

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

1080

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

1081

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

1082

bool match = false;

1083

{

1084

char *interface = NULL;

1085

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

1086

interface))){

1087

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

1088

match = true;

1089

break;

1090

}

1091

}

1092

}

1093

if(not match){

1094

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

1095

connect to the server */

1096

if(debug){

1097

char interface[IF_NAMESIZE];

1098

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

1099

perror_plus("if_indextoname");

1100

} else {

1101

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

1102

" \"%s\"\n",

1103

if_indextoname((unsigned int)if_index,

1104

interface));

1105

}

1106

}

1107

return -1;

1108

}

1109

}

1110

1111

ret = init_gnutls_session(&session, mc);

655

1112

if(ret != 0){

656

1113

return -1;

657

1114

}

658

1115

659

1116

if(debug){

660

1117

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

661

PRIu16 "\n", ip, port);

1118

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

662

1119

}

663

1120

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1121

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

665

1122

if(tcp_sd < 0){

666

1123

int e = errno;

667

1124

perror_plus("socket");

674

1131

goto mandos_end;

675

1132

}

676

1133

677

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

678

1134

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1135

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

1136

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

1137

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

681

1138

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

1139

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

1140

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

1141

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

684

1142

}

685

1143

if(ret < 0 ){

686

1144

int e = errno;

695

1153

goto mandos_end;

696

1154

}

697

1155

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

1156

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

1157

if(IN6_IS_ADDR_LINKLOCAL

1158

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

705

1159

if(if_index == AVAHI_IF_UNSPEC){

706

1160

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

707

1161

" incomplete without a network interface\n");

709

1163

goto mandos_end;

710

1164

}

711

1165

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1166

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

713

1167

}

714

1168

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1169

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

718

1170

}

719

1171

720

1172

if(quit_now){

728

1180

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

729

1181

perror_plus("if_indextoname");

730

1182

} else {

731

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

732

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

1183

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

1184

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

733

1185

}

734

1186

} else {

735

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

736

ip, port);

1187

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

1188

ip, (uintmax_t)port);

737

1189

}

738

1190

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1191

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

741

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

744

} else {

745

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

746

sizeof(addrstr));

747

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

754

}

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

760

}

761

762

if(af == AF_INET6){

763

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

764

} else {

765

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

766

}

767

if(ret < 0){

768

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

769

int e = errno;

770

perror_plus("connect");

771

errno = e;

772

}

773

goto mandos_end;

774

}

775

776

if(quit_now){

777

errno = EINTR;

778

goto mandos_end;

1192

if(af == AF_INET6){

1193

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

1194

sizeof(struct sockaddr_in6),

1195

addrstr, sizeof(addrstr), NULL, 0,

1196

NI_NUMERICHOST);

1197

} else {

1198

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

1199

sizeof(struct sockaddr_in),

1200

addrstr, sizeof(addrstr), NULL, 0,

1201

NI_NUMERICHOST);

1202

}

1203

if(ret == EAI_SYSTEM){

1204

perror_plus("getnameinfo");

1205

} else if(ret != 0) {

1206

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

1207

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

1208

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

1209

}

1210

}

1211

1212

if(quit_now){

1213

errno = EINTR;

1214

goto mandos_end;

1215

}

1216

1217

while(true){

1218

if(af == AF_INET6){

1219

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

1220

sizeof(struct sockaddr_in6));

1221

} else {

1222

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

1223

sizeof(struct sockaddr_in));

1224

}

1225

if(ret < 0){

1226

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

1227

and if_index != AVAHI_IF_UNSPEC

1228

and connect_to == NULL

1229

and not route_added and

1230

((af == AF_INET6 and not

1231

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1232

&to)->sin6_addr)))

1233

or (af == AF_INET and

1234

/* Not a a IPv4LL address */

1235

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

1236

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

1237

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

1238

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

1239

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

1240

connect to a Mandos server announced by Avahi on a server

1241

host with a global address. Work around this by retrying

1242

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

1243

1244

Avahi bug reference:

1245

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

1246

https://bugs.debian.org/587961

1247

*/

1248

if(debug){

1249

fprintf_plus(stderr, "Mandos server unreachable, trying"

1250

" direct route\n");

1251

}

1252

int e = errno;

1253

route_added = add_local_route(ip, if_index);

1254

if(route_added){

1255

continue;

1256

}

1257

errno = e;

1258

}

1259

if(errno != ECONNREFUSED or debug){

1260

int e = errno;

1261

perror_plus("connect");

1262

errno = e;

1263

}

1264

goto mandos_end;

1265

}

1266

1267

if(quit_now){

1268

errno = EINTR;

1269

goto mandos_end;

1270

}

1271

break;

779

1272

}

780

1273

781

1274

const char *out = mandos_protocol_version;

817

1310

goto mandos_end;

818

1311

}

819

1312

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1313

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

1314

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

1315

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

1316

gnutls_transport_set_ptr(session,

1317

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

1318

823

1319

if(quit_now){

824

1320

errno = EINTR;

929

1425

if(buffer_length > 0){

930

1426

ssize_t decrypted_buffer_size;

931

1427

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1428

&decrypted_buffer, mc);

933

1429

if(decrypted_buffer_size >= 0){

934

1430

935

1431

written = 0;

961

1457

962

1458

mandos_end:

963

1459

{

1460

if(route_added){

1461

if(not delete_local_route(ip, if_index)){

1462

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

1463

" interface %d", ip, if_index);

1464

}

1465

}

964

1466

int e = errno;

965

1467

free(decrypted_buffer);

966

1468

free(buffer);

967

1469

if(tcp_sd >= 0){

968

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

1470

ret = close(tcp_sd);

969

1471

}

970

1472

if(ret == -1){

971

1473

if(e == 0){

983

1485

return retval;

984

1486

}

985

1487

1488

__attribute__((nonnull))

986

1489

static void resolve_callback(AvahiSServiceResolver *r,

987

1490

AvahiIfIndex interface,

988

1491

AvahiProtocol proto,

996

1499

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1500

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1501

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1502

void *mc){

1503

if(r == NULL){

1504

return;

1505

}

1001

1506

1002

1507

/* Called whenever a service has been resolved successfully or

1003

1508

timed out */

1004

1509

1005

1510

if(quit_now){

1511

avahi_s_service_resolver_free(r);

1006

1512

return;

1007

1513

}

1008

1514

1012

1518

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

1013

1519

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

1014

1520

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1521

avahi_strerror(avahi_server_errno

1522

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

1016

1523

break;

1017

1524

1018

1525

case AVAHI_RESOLVER_FOUND:

1024

1531

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

1025

1532

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

1026

1533

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1534

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

1535

interface,

1536

avahi_proto_to_af(proto),

1537

mc);

1029

1538

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1539

avahi_simple_poll_quit(simple_poll);

1031

1540

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1541

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

1542

avahi_proto_to_af(proto),

1543

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

1544

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

1545

" list\n", name);

1546

}

1034

1547

}

1035

1548

}

1036

1549

}

1046

1559

const char *domain,

1047

1560

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1561

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1562

void *mc){

1563

if(b == NULL){

1564

return;

1565

}

1051

1566

1052

1567

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

1053

1568

is removed from the LAN */

1061

1576

case AVAHI_BROWSER_FAILURE:

1062

1577

1063

1578

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1579

avahi_strerror(avahi_server_errno

1580

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

1581

avahi_simple_poll_quit(simple_poll);

1066

1582

return;

1067

1583

1068

1584

case AVAHI_BROWSER_NEW:

1071

1587

the callback function is called the Avahi server will free the

1072

1588

resolver for us. */

1073

1589

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1590

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

1591

interface, protocol, name, type,

1592

domain, protocol, 0,

1593

resolve_callback, mc) == NULL)

1077

1594

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

1078

1595

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1596

avahi_strerror(avahi_server_errno

1597

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

1080

1598

break;

1081

1599

1082

1600

case AVAHI_BROWSER_REMOVE:

1101

1619

signal_received = sig;

1102

1620

int old_errno = errno;

1103

1621

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1622

if(simple_poll != NULL){

1623

avahi_simple_poll_quit(simple_poll);

1106

1624

}

1107

1625

errno = old_errno;

1108

1626

}

1109

1627

1628

__attribute__((nonnull, warn_unused_result))

1110

1629

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

1111

1630

int ret;

1631

error_t ret_errno;

1112

1632

1113

1633

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

1114

1634

if(s < 0){

1635

ret_errno = errno;

1115

1636

perror_plus("socket");

1637

errno = ret_errno;

1116

1638

return false;

1117

1639

}

1118

strcpy(ifr->ifr_name, ifname);

1640

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

1641

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

1119

1642

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1643

if(ret == -1){

1121

1644

if(debug){

1645

ret_errno = errno;

1122

1646

perror_plus("ioctl SIOCGIFFLAGS");

1647

errno = ret_errno;

1123

1648

}

1124

1649

return false;

1125

1650

}

1126

1651

return true;

1127

1652

}

1128

1653

1654

__attribute__((nonnull, warn_unused_result))

1129

1655

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

1130

1656

1131

1657

/* Reject the loopback device */

1173

1699

* corresponds to an acceptable network device.

1174

1700

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

1175

1701

*/

1702

__attribute__((nonnull, warn_unused_result))

1176

1703

int good_interface(const struct dirent *if_entry){

1177

1704

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

1178

1705

return 0;

1194

1721

}

1195

1722

1196

1723

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

if(not (ifr.ifr_flags & IFF_UP)){

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

if(not (ifr.ifr_flags & IFF_RUNNING)){

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1724

* This function determines if a network interface is up.

1725

*/

1726

__attribute__((nonnull, warn_unused_result))

1727

bool interface_is_up(const char *interface){

1728

struct ifreq ifr;

1729

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

1730

if(debug){

1731

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

1732

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

1733

}

1734

return false;

1735

}

1736

1737

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

1738

}

1739

1740

/*

1741

* This function determines if a network interface is running

1742

*/

1743

__attribute__((nonnull, warn_unused_result))

1744

bool interface_is_running(const char *interface){

1745

struct ifreq ifr;

1746

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

1747

if(debug){

1748

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

1749

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

1750

}

1751

return false;

1752

}

1753

1754

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

1755

}

1756

1757

__attribute__((nonnull, pure, warn_unused_result))

1239

1758

int notdotentries(const struct dirent *direntry){

1240

1759

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

1241

1760

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

1248

1767

}

1249

1768

1250

1769

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

1770

__attribute__((nonnull, warn_unused_result))

1251

1771

int runnable_hook(const struct dirent *direntry){

1252

1772

int ret;

1253

1773

size_t sret;

1261

1781

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

1262

1782

"abcdefghijklmnopqrstuvwxyz"

1263

1783

"0123456789"

1264

"_-");

1784

"_.-");

1265

1785

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

1266

1786

/* Contains non-allowed characters */

1267

1787

if(debug){

1271

1791

return 0;

1272

1792

}

1273

1793

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1794

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

1282

1795

if(ret == -1){

1283

1796

if(debug){

1284

1797

perror_plus("Could not stat hook");

1308

1821

return 1;

1309

1822

}

1310

1823

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1824

__attribute__((nonnull, warn_unused_result))

1825

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1826

mandos_context *mc){

1312

1827

int ret;

1313

1828

struct timespec now;

1314

1829

struct timespec waited_time;

1315

1830

intmax_t block_time;

1316

1831

1317

1832

while(true){

1318

if(mc.current_server == NULL){

1319

if (debug){

1833

if(mc->current_server == NULL){

1834

if(debug){

1320

1835

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

1321

1836

" No timeout!\n");

1322

1837

}

1323

1838

ret = avahi_simple_poll_iterate(s, -1);

1324

1839

} else {

1325

if (debug){

1840

if(debug){

1326

1841

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

1327

1842

" it, or wait\n");

1328

1843

}

1335

1850

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

1336

1851

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

1337

1852

waited_time.tv_sec = (now.tv_sec

1338

- mc.current_server->last_seen.tv_sec);

1853

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

1339

1854

waited_time.tv_nsec = (now.tv_nsec

1340

- mc.current_server->last_seen.tv_nsec);

1855

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

1341

1856

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

1342

1857

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

1343

1858

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

1345

1860

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

1346

1861

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

1347

1862

1348

if (debug){

1863

if(debug){

1349

1864

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

1350

1865

block_time);

1351

1866

}

1352

1867

1353

1868

if(block_time <= 0){

1354

ret = start_mandos_communication(mc.current_server->ip,

1355

mc.current_server->port,

1356

mc.current_server->if_index,

1357

mc.current_server->af);

1869

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

1870

mc->current_server->port,

1871

mc->current_server->if_index,

1872

mc->current_server->af, mc);

1358

1873

if(ret == 0){

1359

avahi_simple_poll_quit(mc.simple_poll);

1874

avahi_simple_poll_quit(s);

1360

1875

return 0;

1361

1876

}

1362

1877

ret = clock_gettime(CLOCK_MONOTONIC,

1363

&mc.current_server->last_seen);

1878

&mc->current_server->last_seen);

1364

1879

if(ret == -1){

1365

1880

perror_plus("clock_gettime");

1366

1881

return -1;

1367

1882

}

1368

mc.current_server = mc.current_server->next;

1883

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

1369

1884

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

1370

1885

servers, but don't block */

1371

1886

}

1373

1888

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

1374

1889

}

1375

1890

if(ret != 0){

1376

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

1891

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

1377

1892

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

1378

1893

}

1379

1894

}

1380

1895

}

1381

1896

}

1382

1897

1383

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

1898

__attribute__((nonnull))

1899

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

1384

1900

const float delay){

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1901

struct dirent **direntries = NULL;

1902

if(hookdir_fd == -1){

1903

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1904

| O_CLOEXEC);

1905

if(hookdir_fd == -1){

1906

if(errno == ENOENT){

1907

if(debug){

1908

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

1909

" found\n", hookdir);

1910

}

1911

} else {

1912

perror_plus("open");

1913

}

1914

return;

1915

}

1916

}

1917

#ifdef __GLIBC__

1918

#if __GLIBC_PREREQ(2, 15)

1919

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

1920

runnable_hook, alphasort);

1921

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

1922

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

1923

alphasort);

1924

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

1925

#else /* not __GLIBC__ */

1926

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

1927

alphasort);

1928

#endif /* not __GLIBC__ */

1390

1929

if(numhooks == -1){

1391

1930

perror_plus("scandir");

1392

} else {

1393

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

1394

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

1395

direntry = direntries[i];

1396

char *fullname = NULL;

1397

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

1398

if(ret < 0){

1931

return;

1932

}

1933

struct dirent *direntry;

1934

int ret;

1935

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

1936

if(devnull == -1){

1937

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

1938

return;

1939

}

1940

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

1941

direntry = direntries[i];

1942

if(debug){

1943

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

1944

direntry->d_name);

1945

}

1946

pid_t hook_pid = fork();

1947

if(hook_pid == 0){

1948

/* Child */

1949

/* Raise privileges */

1950

errno = raise_privileges_permanently();

1951

if(errno != 0){

1952

perror_plus("Failed to raise privileges");

1953

_exit(EX_NOPERM);

1954

}

1955

/* Set group */

1956

errno = 0;

1957

ret = setgid(0);

1958

if(ret == -1){

1959

perror_plus("setgid");

1960

_exit(EX_NOPERM);

1961

}

1962

/* Reset supplementary groups */

1963

errno = 0;

1964

ret = setgroups(0, NULL);

1965

if(ret == -1){

1966

perror_plus("setgroups");

1967

_exit(EX_NOPERM);

1968

}

1969

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

1970

if(ret == -1){

1971

perror_plus("setenv");

1972

_exit(EX_OSERR);

1973

}

1974

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

1975

if(ret == -1){

1976

perror_plus("setenv");

1977

_exit(EX_OSERR);

1978

}

1979

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

1980

if(ret == -1){

1981

perror_plus("setenv");

1982

_exit(EX_OSERR);

1983

}

1984

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

1985

if(ret == -1){

1986

perror_plus("setenv");

1987

_exit(EX_OSERR);

1988

}

1989

char *delaystring;

1990

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

1991

if(ret == -1){

1399

1992

perror_plus("asprintf");

1400

continue;

1401

}

1402

if(debug){

1403

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

1404

direntry->d_name);

1405

}

1406

pid_t hook_pid = fork();

1407

if(hook_pid == 0){

1408

/* Child */

1409

dup2(devnull, STDIN_FILENO);

1410

close(devnull);

1411

dup2(STDERR_FILENO, STDOUT_FILENO);

1412

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

1413

if(ret == -1){

1414

perror_plus("setenv");

1415

return false;

1416

}

1417

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

1418

if(ret == -1){

1419

perror_plus("setenv");

1420

return false;

1421

}

1422

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

1423

if(ret == -1){

1424

perror_plus("setenv");

1425

return false;

1426

}

1427

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

1428

if(ret == -1){

1429

perror_plus("setenv");

1430

return false;

1431

}

1432

char *delaystring;

1433

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

1434

if(ret == -1){

1435

perror_plus("asprintf");

1436

return false;

1437

}

1438

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

1439

if(ret == -1){

1440

free(delaystring);

1441

perror_plus("setenv");

1442

return false;

1443

}

1993

_exit(EX_OSERR);

1994

}

1995

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

1996

if(ret == -1){

1444

1997

free(delaystring);

1445

ret = execl(fullname, direntry->d_name, mode, NULL);

1446

perror_plus("execl");

1447

} else {

1448

int status;

1449

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

1450

perror_plus("waitpid");

1451

free(fullname);

1452

continue;

1453

}

1454

if(WIFEXITED(status)){

1455

if(WEXITSTATUS(status) != 0){

1456

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

1457

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

1458

WEXITSTATUS(status));

1459

free(fullname);

1460

continue;

1461

}

1462

} else if(WIFSIGNALED(status)){

1463

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

1464

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

1465

WTERMSIG(status));

1466

free(fullname);

1467

continue;

1468

} else {

1469

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

1470

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

1471

free(fullname);

1472

continue;

1473

}

1474

}

1475

free(fullname);

1476

if(debug){

1477

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

1478

direntry->d_name);

1479

}

1480

}

1481

close(devnull);

1482

}

1483

return true;

1998

perror_plus("setenv");

1999

_exit(EX_OSERR);

2000

}

2001

free(delaystring);

2002

if(connect_to != NULL){

2003

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

2004

if(ret == -1){

2005

perror_plus("setenv");

2006

_exit(EX_OSERR);

2007

}

2008

}

2009

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

2010

direntry->d_name,

2011

O_RDONLY));

2012

if(hook_fd == -1){

2013

perror_plus("openat");

2014

_exit(EXIT_FAILURE);

2015

}

2016

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

2017

perror_plus("close");

2018

_exit(EXIT_FAILURE);

2019

}

2020

ret = dup2(devnull, STDIN_FILENO);

2021

if(ret == -1){

2022

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

2023

_exit(EX_OSERR);

2024

}

2025

ret = close(devnull);

2026

if(ret == -1){

2027

perror_plus("close");

2028

_exit(EX_OSERR);

2029

}

2030

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2031

if(ret == -1){

2032

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

2033

_exit(EX_OSERR);

2034

}

2035

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

2036

environ) == -1){

2037

perror_plus("fexecve");

2038

_exit(EXIT_FAILURE);

2039

}

2040

} else {

2041

if(hook_pid == -1){

2042

perror_plus("fork");

2043

free(direntry);

2044

continue;

2045

}

2046

int status;

2047

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

2048

perror_plus("waitpid");

2049

free(direntry);

2050

continue;

2051

}

2052

if(WIFEXITED(status)){

2053

if(WEXITSTATUS(status) != 0){

2054

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

2055

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

2056

WEXITSTATUS(status));

2057

free(direntry);

2058

continue;

2059

}

2060

} else if(WIFSIGNALED(status)){

2061

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

2062

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

2063

WTERMSIG(status));

2064

free(direntry);

2065

continue;

2066

} else {

2067

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

2068

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

2069

free(direntry);

2070

continue;

2071

}

2072

}

2073

if(debug){

2074

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

2075

direntry->d_name);

2076

}

2077

free(direntry);

2078

}

2079

free(direntries);

2080

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

2081

perror_plus("close");

2082

} else {

2083

hookdir_fd = -1;

2084

}

2085

close(devnull);

2086

}

2087

2088

__attribute__((nonnull, warn_unused_result))

2089

error_t bring_up_interface(const char *const interface,

2090

const float delay){

2091

error_t old_errno = errno;

2092

int ret;

2093

struct ifreq network;

2094

unsigned int if_index = if_nametoindex(interface);

2095

if(if_index == 0){

2096

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

2097

errno = old_errno;

2098

return ENXIO;

2099

}

2100

2101

if(quit_now){

2102

errno = old_errno;

2103

return EINTR;

2104

}

2105

2106

if(not interface_is_up(interface)){

2107

error_t ret_errno = 0, ioctl_errno = 0;

2108

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

2109

ret_errno = errno;

2110

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

2111

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

2112

errno = old_errno;

2113

return ret_errno;

2114

}

2115

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

2116

2117

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

2118

if(sd == -1){

2119

ret_errno = errno;

2120

perror_plus("socket");

2121

errno = old_errno;

2122

return ret_errno;

2123

}

2124

2125

if(quit_now){

2126

ret = close(sd);

2127

if(ret == -1){

2128

perror_plus("close");

2129

}

2130

errno = old_errno;

2131

return EINTR;

2132

}

2133

2134

if(debug){

2135

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

2136

interface);

2137

}

2138

2139

/* Raise privileges */

2140

ret_errno = raise_privileges();

2141

if(ret_errno != 0){

2142

errno = ret_errno;

2143

perror_plus("Failed to raise privileges");

2144

}

2145

2146

#ifdef __linux__

2147

int ret_linux;

2148

bool restore_loglevel = false;

2149

if(ret_errno == 0){

2150

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2151

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

2152

ret_linux = klogctl(8, NULL, 5);

2153

if(ret_linux == -1){

2154

perror_plus("klogctl");

2155

} else {

2156

restore_loglevel = true;

2157

}

2158

}

2159

#endif /* __linux__ */

2160

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

2161

ioctl_errno = errno;

2162

#ifdef __linux__

2163

if(restore_loglevel){

2164

ret_linux = klogctl(7, NULL, 0);

2165

if(ret_linux == -1){

2166

perror_plus("klogctl");

2167

}

2168

}

2169

#endif /* __linux__ */

2170

2171

/* If raise_privileges() succeeded above */

2172

if(ret_errno == 0){

2173

/* Lower privileges */

2174

ret_errno = lower_privileges();

2175

if(ret_errno != 0){

2176

errno = ret_errno;

2177

perror_plus("Failed to lower privileges");

2178

}

2179

}

2180

2181

/* Close the socket */

2182

ret = close(sd);

2183

if(ret == -1){

2184

perror_plus("close");

2185

}

2186

2187

if(ret_setflags == -1){

2188

errno = ioctl_errno;

2189

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2190

errno = old_errno;

2191

return ioctl_errno;

2192

}

2193

} else if(debug){

2194

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

2195

interface);

2196

}

2197

2198

/* Sleep checking until interface is running.

2199

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

2200

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

2201

if(interface_is_running(interface)){

2202

break;

2203

}

2204

struct timespec sleeptime = { .tv_nsec = 250000000 };

2205

ret = nanosleep(&sleeptime, NULL);

2206

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

2207

perror_plus("nanosleep");

2208

}

2209

}

2210

2211

errno = old_errno;

2212

return 0;

2213

}

2214

2215

__attribute__((nonnull, warn_unused_result))

2216

error_t take_down_interface(const char *const interface){

2217

error_t old_errno = errno;

2218

struct ifreq network;

2219

unsigned int if_index = if_nametoindex(interface);

2220

if(if_index == 0){

2221

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

2222

errno = old_errno;

2223

return ENXIO;

2224

}

2225

if(interface_is_up(interface)){

2226

error_t ret_errno = 0, ioctl_errno = 0;

2227

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

2228

ret_errno = errno;

2229

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

2230

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

2231

errno = old_errno;

2232

return ret_errno;

2233

}

2234

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

2235

2236

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

2237

if(sd == -1){

2238

ret_errno = errno;

2239

perror_plus("socket");

2240

errno = old_errno;

2241

return ret_errno;

2242

}

2243

2244

if(debug){

2245

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

2246

interface);

2247

}

2248

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

}

2268

2269

/* Close the socket */

2270

int ret = close(sd);

2271

if(ret == -1){

2272

perror_plus("close");

2273

}

2274

2275

if(ret_setflags == -1){

2276

errno = ioctl_errno;

2277

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2278

errno = old_errno;

2279

return ioctl_errno;

2280

}

2281

} else if(debug){

2282

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

2283

interface);

2284

}

2285

2286

errno = old_errno;

2287

return 0;

1484

2288

}

1485

2289

1486

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 };

1487

2296

AvahiSServiceBrowser *sb = NULL;

1488

int error;

2297

error_t ret_errno;

1489

2298

int ret;

1490

2299

intmax_t tmpmax;

1491

2300

char *tmp;

1492

2301

int exitcode = EXIT_SUCCESS;

1493

const char *interface = "";

1494

struct ifreq network;

1495

int sd = -1;

1496

bool take_down_interface = false;

1497

uid_t uid;

1498

gid_t gid;

1499

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

1500

bool tempdir_created = false;

2302

char *interfaces_to_take_down = NULL;

2303

size_t interfaces_to_take_down_size = 0;

2304

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

2305

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

2306

char *tempdir = NULL;

1501

2307

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1502

2308

const char *seckey = PATHDIR "/" SECKEY;

1503

2309

const char *pubkey = PATHDIR "/" PUBKEY;

2310

const char *dh_params_file = NULL;

2311

char *interfaces_hooks = NULL;

1504

2312

1505

2313

bool gnutls_initialized = false;

1506

2314

bool gpgme_initialized = false;

1558

2366

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

1559

2367

" Diffie-Hellman key exchange",

1560

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 },

1561

2374

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

1562

2375

.arg = "STRING",

1563

2376

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

1568

2381

.group = 2 },

1569

2382

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

1570

2383

.arg = "SECONDS",

1571

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

2384

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

1572

2385

.group = 2 },

1573

2386

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

1574

2387

.arg = "DIR",

1597

2410

connect_to = arg;

1598

2411

break;

1599

2412

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

1600

interface = arg;

2413

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

2414

arg, (int)',');

2415

if(ret_errno != 0){

2416

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

2417

}

1601

2418

break;

1602

2419

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

1603

2420

seckey = arg;

1614

2431

}

1615

2432

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

1616

2433

break;

2434

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

2435

dh_params_file = arg;

2436

break;

1617

2437

case 130: /* --priority */

1618

2438

mc.priority = arg;

1619

2439

break;

1646

2466

argp_state_help(state, state->out_stream,

1647

2467

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1648

2468

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

1651

2469

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

1652

2470

exit(argp_err_exit_status);

1653

2471

break;

1677

2495

goto end;

1678

2496

}

1679

2497

}

1680

1681

if(getuid() == 0){

2498

2499

{

1682

2500

/* Work around Debian bug #633582:

1683

2501

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

1684

struct stat st;

1685

1686

/* Re-raise priviliges */

1687

errno = 0;

1688

ret = seteuid(0);

1689

if(ret == -1){

1690

perror_plus("seteuid");

1691

}

1692

1693

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

1694

int seckey_fd = open(seckey, O_RDONLY);

1695

if(seckey_fd == -1){

1696

perror_plus("open");

1697

} else {

1698

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

1699

if(ret == -1){

1700

perror_plus("fstat");

1701

} else {

1702

if(S_ISREG(st.st_mode)

1703

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

1704

ret = fchown(seckey_fd, uid, gid);

1705

if(ret == -1){

1706

perror_plus("fchown");

1707

}

1708

}

1709

}

1710

TEMP_FAILURE_RETRY(close(seckey_fd));

1711

}

1712

}

1713

1714

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

1715

int pubkey_fd = open(pubkey, O_RDONLY);

1716

if(pubkey_fd == -1){

1717

perror_plus("open");

1718

} else {

1719

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

1720

if(ret == -1){

1721

perror_plus("fstat");

1722

} else {

1723

if(S_ISREG(st.st_mode)

1724

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

1725

ret = fchown(pubkey_fd, uid, gid);

1726

if(ret == -1){

1727

perror_plus("fchown");

1728

}

1729

}

1730

}

1731

TEMP_FAILURE_RETRY(close(pubkey_fd));

1732

}

1733

}

1734

1735

/* Lower privileges */

1736

errno = 0;

1737

ret = seteuid(uid);

1738

if(ret == -1){

1739

perror_plus("seteuid");

2502

2503

/* Re-raise privileges */

2504

ret_errno = raise_privileges();

2505

if(ret_errno != 0){

2506

errno = ret_errno;

2507

perror_plus("Failed to raise privileges");

2508

} else {

2509

struct stat st;

2510

2511

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

2512

int seckey_fd = open(seckey, O_RDONLY);

2513

if(seckey_fd == -1){

2514

perror_plus("open");

2515

} else {

2516

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

2517

if(ret == -1){

2518

perror_plus("fstat");

2519

} else {

2520

if(S_ISREG(st.st_mode)

2521

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

2522

ret = fchown(seckey_fd, uid, gid);

2523

if(ret == -1){

2524

perror_plus("fchown");

2525

}

2526

}

2527

}

2528

close(seckey_fd);

2529

}

2530

}

2531

2532

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

2533

int pubkey_fd = open(pubkey, O_RDONLY);

2534

if(pubkey_fd == -1){

2535

perror_plus("open");

2536

} else {

2537

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

2538

if(ret == -1){

2539

perror_plus("fstat");

2540

} else {

2541

if(S_ISREG(st.st_mode)

2542

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

2543

ret = fchown(pubkey_fd, uid, gid);

2544

if(ret == -1){

2545

perror_plus("fchown");

2546

}

2547

}

2548

}

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

2575

/* Lower privileges */

2576

ret_errno = lower_privileges();

2577

if(ret_errno != 0){

2578

errno = ret_errno;

2579

perror_plus("Failed to lower privileges");

2580

}

2581

}

2582

}

2583

2584

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

2585

{

2586

char *interface = NULL;

2587

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

2588

interface))){

2589

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

2590

and if_nametoindex(interface) == 0){

2591

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

2592

fprintf_plus(stderr, "Not using nonexisting interface"

2593

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

2594

}

2595

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

2596

interface = NULL;

2597

}

1740

2598

}

1741

2599

}

1742

2600

1743

2601

/* Run network hooks */

1744

2602

{

1745

if(getuid() == 0){

1746

/* Re-raise priviliges */

1747

errno = 0;

1748

ret = seteuid(0);

1749

if(ret == -1){

1750

perror_plus("seteuid");

1751

}

1752

}

1753

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

1754

goto end;

1755

}

1756

if(getuid() == 0){

1757

/* Lower privileges */

1758

errno = 0;

1759

ret = seteuid(uid);

1760

if(ret == -1){

1761

perror_plus("seteuid");

1762

}

1763

}

2603

if(mc.interfaces != NULL){

2604

interfaces_hooks = malloc(mc.interfaces_size);

2605

if(interfaces_hooks == NULL){

2606

perror_plus("malloc");

2607

goto end;

2608

}

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);

1764

2614

}

1765

2615

1766

2616

if(not debug){

1767

2617

avahi_set_log_function(empty_log);

1768

2618

}

1769

2619

1770

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

1771

struct dirent **direntries;

1772

/* First look for interfaces that are up */

1773

ret = scandir(sys_class_net, &direntries, up_interface,

1774

alphasort);

1775

if(ret == 0){

1776

/* No up interfaces, look for any good interfaces */

1777

free(direntries);

1778

ret = scandir(sys_class_net, &direntries, good_interface,

1779

alphasort);

1780

}

1781

if(ret >= 1){

1782

/* Pick the first interface returned */

1783

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

1784

if(debug){

1785

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

1786

}

1787

if(interface == NULL){

1788

perror_plus("malloc");

1789

free(direntries);

1790

exitcode = EXIT_FAILURE;

1791

goto end;

1792

}

1793

free(direntries);

1794

} else {

1795

free(direntries);

1796

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

1797

exitcode = EXIT_FAILURE;

1798

goto end;

1799

}

1800

}

1801

1802

2620

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

1803

2621

from the signal handler */

1804

2622

/* Initialize the pseudo-RNG for Avahi */

1805

2623

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

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2624

simple_poll = avahi_simple_poll_new();

2625

if(simple_poll == NULL){

1808

2626

fprintf_plus(stderr,

1809

2627

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

1810

2628

exitcode = EX_UNAVAILABLE;

1874

2692

}

1875

2693

}

1876

2694

1877

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

1878

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

1879

if_index = (AvahiIfIndex) if_nametoindex(interface);

1880

if(if_index == 0){

1881

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

1882

exitcode = EX_UNAVAILABLE;

1883

goto end;

1884

}

1885

1886

if(quit_now){

1887

goto end;

1888

}

1889

1890

/* Re-raise priviliges */

1891

errno = 0;

1892

ret = seteuid(0);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

1897

#ifdef __linux__

1898

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1899

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

1900

ret = klogctl(8, NULL, 5);

1901

bool restore_loglevel = true;

1902

if(ret == -1){

1903

restore_loglevel = false;

1904

perror_plus("klogctl");

1905

}

1906

#endif /* __linux__ */

1907

1908

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1909

if(sd < 0){

1910

perror_plus("socket");

1911

exitcode = EX_OSERR;

1912

#ifdef __linux__

1913

if(restore_loglevel){

1914

ret = klogctl(7, NULL, 0);

1915

if(ret == -1){

1916

perror_plus("klogctl");

1917

}

1918

}

1919

#endif /* __linux__ */

1920

/* Lower privileges */

1921

errno = 0;

1922

ret = seteuid(uid);

1923

if(ret == -1){

1924

perror_plus("seteuid");

1925

}

1926

goto end;

1927

}

1928

strcpy(network.ifr_name, interface);

1929

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

1930

if(ret == -1){

1931

perror_plus("ioctl SIOCGIFFLAGS");

1932

#ifdef __linux__

1933

if(restore_loglevel){

1934

ret = klogctl(7, NULL, 0);

1935

if(ret == -1){

1936

perror_plus("klogctl");

1937

}

1938

}

1939

#endif /* __linux__ */

1940

exitcode = EX_OSERR;

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

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

1950

network.ifr_flags |= IFF_UP;

1951

take_down_interface = true;

1952

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

1953

if(ret == -1){

1954

take_down_interface = false;

1955

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1956

exitcode = EX_OSERR;

1957

#ifdef __linux__

1958

if(restore_loglevel){

1959

ret = klogctl(7, NULL, 0);

1960

if(ret == -1){

1961

perror_plus("klogctl");

2695

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

2696

if(mc.interfaces == NULL){

2697

struct dirent **direntries = NULL;

2698

/* Look for any good interfaces */

2699

ret = scandir(sys_class_net, &direntries, good_interface,

2700

alphasort);

2701

if(ret >= 1){

2702

/* Add all found interfaces to interfaces list */

2703

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

2704

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

2705

direntries[i]->d_name);

2706

if(ret_errno != 0){

2707

errno = ret_errno;

2708

perror_plus("argz_add");

2709

free(direntries[i]);

2710

continue;

2711

}

2712

if(debug){

2713

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

2714

direntries[i]->d_name);

2715

}

2716

free(direntries[i]);

2717

}

2718

free(direntries);

2719

} else {

2720

if(ret == 0){

2721

free(direntries);

2722

}

2723

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

2724

exitcode = EXIT_FAILURE;

2725

goto end;

2726

}

2727

}

2728

2729

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

2730

{

2731

char *interface = NULL;

2732

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

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;

1962

2746

}

1963

2747

}

1964

#endif /* __linux__ */

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

}

1974

/* Sleep checking until interface is running.

1975

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

1976

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

1977

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

1978

if(ret == -1){

1979

perror_plus("ioctl SIOCGIFFLAGS");

1980

} else if(network.ifr_flags & IFF_RUNNING){

1981

2748

break;

1982

2749

}

1983

struct timespec sleeptime = { .tv_nsec = 250000000 };

1984

ret = nanosleep(&sleeptime, NULL);

1985

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

1986

perror_plus("nanosleep");

1987

}

1988

}

1989

if(not take_down_interface){

1990

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

1991

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

1992

if(ret == -1){

1993

perror_plus("close");

1994

}

1995

}

1996

#ifdef __linux__

1997

if(restore_loglevel){

1998

/* Restores kernel loglevel to default */

1999

ret = klogctl(7, NULL, 0);

2000

if(ret == -1){

2001

perror_plus("klogctl");

2002

}

2003

}

2004

#endif /* __linux__ */

2005

/* Lower privileges */

2006

errno = 0;

2007

/* Lower privileges */

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2011

}

2750

bool interface_was_up = interface_is_up(interface);

2751

errno = bring_up_interface(interface, delay);

2752

if(not interface_was_up){

2753

if(errno != 0){

2754

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

2755

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

2756

} else {

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

}

2763

}

2764

}

2765

}

2766

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

2767

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

2768

}

2769

}

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);

2012

2778

}

2013

2779

2014

2780

if(quit_now){

2015

2781

goto end;

2016

2782

}

2017

2783

2018

ret = init_gnutls_global(pubkey, seckey);

2784

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

2019

2785

if(ret == -1){

2020

2786

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

2021

2787

exitcode = EX_UNAVAILABLE;

2028

2794

goto end;

2029

2795

}

2030

2796

2031

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){

2032

2807

perror_plus("mkdtemp");

2033

2808

goto end;

2034

2809

}

2035

tempdir_created = true;

2036

2810

2037

2811

if(quit_now){

2038

2812

goto end;

2039

2813

}

2040

2814

2041

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

2815

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

2042

2816

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

2043

2817

exitcode = EX_UNAVAILABLE;

2044

2818

goto end;

2054

2828

/* Connect directly, do not use Zeroconf */

2055

2829

/* (Mainly meant for debugging) */

2056

2830

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

2831

2057

2832

if(address == NULL){

2058

2833

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

2059

2834

exitcode = EX_USAGE;

2064

2839

goto end;

2065

2840

}

2066

2841

2067

uint16_t port;

2842

in_port_t port;

2068

2843

errno = 0;

2069

2844

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

2070

2845

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

2071

or tmpmax != (uint16_t)tmpmax){

2846

or tmpmax != (in_port_t)tmpmax){

2072

2847

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

2073

2848

exitcode = EX_USAGE;

2074

2849

goto end;

2075

2850

}

2076

2851

2077

2852

if(quit_now){

2078

2853

goto end;

2079

2854

}

2080

2855

2081

port = (uint16_t)tmpmax;

2856

port = (in_port_t)tmpmax;

2082

2857

*address = '\0';

2083

2858

/* Colon in address indicates IPv6 */

2084

2859

int af;

2100

2875

}

2101

2876

2102

2877

while(not quit_now){

2103

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

2878

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

2879

&mc);

2104

2880

if(quit_now or ret == 0){

2105

2881

break;

2106

2882

}

2108

2884

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

2109

2885

(int)retry_interval);

2110

2886

}

2111

sleep((int)retry_interval);

2887

sleep((unsigned int)retry_interval);

2112

2888

}

2113

2889

2114

if (not quit_now){

2890

if(not quit_now){

2115

2891

exitcode = EXIT_SUCCESS;

2116

2892

}

2117

2893

2132

2908

config.publish_domain = 0;

2133

2909

2134

2910

/* Allocate a new server */

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2911

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2912

&config, NULL, NULL, &ret_errno);

2138

2913

2139

2914

/* Free the Avahi configuration data */

2140

2915

avahi_server_config_free(&config);

2143

2918

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

2144

2919

if(mc.server == NULL){

2145

2920

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

2146

avahi_strerror(error));

2921

avahi_strerror(ret_errno));

2147

2922

exitcode = EX_UNAVAILABLE;

2148

2923

goto end;

2149

2924

}

2155

2930

/* Create the Avahi service browser */

2156

2931

sb = avahi_s_service_browser_new(mc.server, if_index,

2157

2932

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2158

NULL, 0, browse_callback, NULL);

2933

NULL, 0, browse_callback,

2934

(void *)&mc);

2159

2935

if(sb == NULL){

2160

2936

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

2161

2937

avahi_strerror(avahi_server_errno(mc.server)));

2172

2948

if(debug){

2173

2949

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

2174

2950

}

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2951

2952

ret = avahi_loop_with_timeout(simple_poll,

2953

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

2178

2954

if(debug){

2179

2955

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

2180

2956

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

2187

2963

}

2188

2964

2189

2965

/* Cleanup things */

2966

free(mc.interfaces);

2967

2190

2968

if(sb != NULL)

2191

2969

avahi_s_service_browser_free(sb);

2192

2970

2193

2971

if(mc.server != NULL)

2194

2972

avahi_server_free(mc.server);

2195

2973

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

2974

if(simple_poll != NULL)

2975

avahi_simple_poll_free(simple_poll);

2198

2976

2199

2977

if(gnutls_initialized){

2200

2978

gnutls_certificate_free_credentials(mc.cred);

2212

2990

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

2213

2991

while(mc.current_server != NULL){

2214

2992

server *next = mc.current_server->next;

2993

#ifdef __GNUC__

2994

#pragma GCC diagnostic push

2995

#pragma GCC diagnostic ignored "-Wcast-qual"

2996

#endif

2997

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

2998

#ifdef __GNUC__

2999

#pragma GCC diagnostic pop

3000

#endif

2215

3001

free(mc.current_server);

2216

3002

mc.current_server = next;

2217

3003

}

2218

3004

}

2219

3005

2220

/* Re-raise priviliges */

3006

/* Re-raise privileges */

2221

3007

{

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

2227

}

2228

}

2229

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Take down the network interface */

2234

if(take_down_interface and geteuid() == 0){

2235

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

2236

if(ret == -1){

2237

perror_plus("ioctl SIOCGIFFLAGS");

2238

} else if(network.ifr_flags & IFF_UP){

2239

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

2240

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

2241

if(ret == -1){

2242

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2243

}

2244

}

2245

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

2246

if(ret == -1){

2247

perror_plus("close");

2248

}

2249

}

2250

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

2258

}

3008

ret_errno = raise_privileges();

3009

if(ret_errno != 0){

3010

errno = ret_errno;

3011

perror_plus("Failed to raise privileges");

3012

} else {

3013

3014

/* Run network hooks */

3015

run_network_hooks("stop", interfaces_hooks != NULL ?

3016

interfaces_hooks : "", delay);

3017

3018

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

3019

{

3020

char *interface = NULL;

3021

while((interface=argz_next(interfaces_to_take_down,

3022

interfaces_to_take_down_size,

3023

interface))){

3024

ret_errno = take_down_interface(interface);

3025

if(ret_errno != 0){

3026

errno = ret_errno;

3027

perror_plus("Failed to take down interface");

3028

}

3029

}

3030

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

3031

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

3032

" down\n");

3033

}

3034

}

3035

}

3036

3037

ret_errno = lower_privileges_permanently();

3038

if(ret_errno != 0){

3039

errno = ret_errno;

3040

perror_plus("Failed to lower privileges permanently");

3041

}

3042

}

3043

3044

free(interfaces_to_take_down);

3045

free(interfaces_hooks);

2259

3046

2260

3047

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

2261

if(tempdir_created){

3048

if(tempdir != NULL){

2262

3049

struct dirent **direntries = NULL;

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

2267

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

2268

direntry = direntries[i];

2269

char *fullname = NULL;

2270

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

2271

direntry->d_name);

2272

if(ret < 0){

2273

perror_plus("asprintf");

2274

continue;

2275

}

2276

ret = remove(fullname);

2277

if(ret == -1){

2278

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

2279

strerror(errno));

2280

}

2281

free(fullname);

3050

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

3051

| O_NOFOLLOW

3052

| O_DIRECTORY

3053

| O_PATH));

3054

if(tempdir_fd == -1){

3055

perror_plus("open");

3056

} else {

3057

#ifdef __GLIBC__

3058

#if __GLIBC_PREREQ(2, 15)

3059

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

3060

notdotentries, alphasort);

3061

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

3062

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

3063

alphasort);

3064

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

3065

#else /* not __GLIBC__ */

3066

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

3067

alphasort);

3068

#endif /* not __GLIBC__ */

3069

if(numentries >= 0){

3070

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

3071

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

3072

if(ret == -1){

3073

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

3074

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

3075

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

3076

}

3077

free(direntries[i]);

3078

}

3079

3080

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

3081

free(direntries);

3082

if(numentries == -1){

3083

perror_plus("scandir");

3084

}

3085

ret = rmdir(tempdir);

3086

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

3087

perror_plus("rmdir");

3088

}

2282

3089

}

2283

}

2284

2285

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

2286

free(direntries);

2287

if (numentries == -1){

2288

perror_plus("scandir");

2289

}

2290

ret = rmdir(tempdir);

2291

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

2292

perror_plus("rmdir");

3090

close(tempdir_fd);

2293

3091

}

2294

3092

}

2295

3093