/mandos/release : revision 237.7.78

9

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

10

*

11

* Everything else is

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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 /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

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42

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

43

stdout, ferror() */

44

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

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stdout, ferror(), remove() */

44

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

45

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

46

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

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strtof(), abort() */

48

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

49

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

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asprintf(), strncpy() */

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

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

51

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

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

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sockaddr_in6, PF_INET6,

55

opendir(), DIR */

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#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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getnameinfo() */

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

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inet_pton(), connect() */

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

61

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

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61

*/

63

62

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

64

63

strtoimax() */

64

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

65

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

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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(),

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

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unlinkat() */

78

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

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

77

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

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78

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

80

79

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

81

80

argp_state, struct argp,

89

88

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

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89

WEXITSTATUS(), WTERMSIG() */

91

90

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

92

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

93

argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

96

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

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EAI_SYSTEM, gai_strerror() */

98

91

99

92

#ifdef __linux__

100

93

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

142

135

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

143

136

char *connect_to = NULL;

144

137

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

148

138

149

139

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

150

140

typedef struct server{

151

141

const char *ip;

152

in_port_t port;

142

uint16_t port;

153

143

AvahiIfIndex if_index;

154

144

int af;

155

145

struct timespec last_seen;

159

149

160

150

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

161

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

162

153

AvahiServer *server;

163

154

gnutls_certificate_credentials_t cred;

164

155

unsigned int dh_bits;

166

157

const char *priority;

167

158

gpgme_ctx_t ctx;

168

159

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

160

} mandos_context;

172

161

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

175

167

176

168

sig_atomic_t quit_now = 0;

177

169

int signal_received = 0;

178

170

179

171

/* Function to use when printing errors */

180

172

void perror_plus(const char *print_text){

181

int e = errno;

182

173

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

183

174

program_invocation_short_name);

184

errno = e;

185

175

perror(print_text);

186

176

}

187

177

188

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

189

178

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

190

179

va_list ap;

191

180

va_start (ap, format);

192

181

193

182

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

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183

program_invocation_short_name));

195

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

184

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

196

185

}

197

186

198

187

/*

200

189

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

201

190

* "buffer_length" is how much is already used.

202

191

*/

203

__attribute__((nonnull, warn_unused_result))

204

192

size_t incbuffer(char **buffer, size_t buffer_length,

205

193

size_t buffer_capacity){

206

194

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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;

195

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

196

if(buffer == NULL){

213

197

return 0;

214

198

}

215

*buffer = new_buf;

216

199

buffer_capacity += BUFFER_SIZE;

217

200

}

218

201

return buffer_capacity;

219

202

}

220

203

221

204

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

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){

205

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

206

int af){

225

207

int ret;

226

208

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

227

209

if(new_server == NULL){

228

210

perror_plus("malloc");

229

return false;

211

return -1;

230

212

}

231

213

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

232

214

.port = port,

234

216

.af = af };

235

217

if(new_server->ip == NULL){

236

218

perror_plus("strdup");

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

return -1;

253

220

}

254

221

/* Special case of first server */

255

if(*current_server == NULL){

222

if (mc.current_server == NULL){

256

223

new_server->next = new_server;

257

224

new_server->prev = new_server;

258

*current_server = new_server;

225

mc.current_server = new_server;

226

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

259

227

} else {

260

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

261

new_server->next = *current_server;

262

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

228

new_server->next = mc.current_server;

229

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

263

230

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

231

mc.current_server->prev = new_server;

232

}

233

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

236

return -1;

237

}

238

return 0;

267

239

}

268

240

269

241

/*

270

242

* Initialize GPGME.

271

243

*/

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){

244

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

245

const char *tempdir){

277

246

gpgme_error_t rc;

278

247

gpgme_engine_info_t engine_info;

279

248

249

280

250

/*

281

251

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

282

252

*/

283

bool import_key(const char * const filename){

253

bool import_key(const char *filename){

284

254

int ret;

285

255

int fd;

286

256

gpgme_data_t pgp_data;

298

268

return false;

299

269

}

300

270

301

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

271

rc = gpgme_op_import(mc.ctx, pgp_data);

302

272

if(rc != GPG_ERR_NO_ERROR){

303

273

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

304

274

gpgme_strsource(rc), gpgme_strerror(rc));

305

275

return false;

306

276

}

307

277

308

ret = close(fd);

278

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

309

279

if(ret == -1){

310

280

perror_plus("close");

311

281

}

348

318

}

349

319

350

320

/* Create new GPGME "context" */

351

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

321

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

352

322

if(rc != GPG_ERR_NO_ERROR){

353

323

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

354

324

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

367

337

* Decrypt OpenPGP data.

368

338

* Returns -1 on error

369

339

*/

370

__attribute__((nonnull, warn_unused_result))

371

340

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

341

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

342

char **plaintext){

375

343

gpgme_data_t dh_crypto, dh_plain;

376

344

gpgme_error_t rc;

377

345

ssize_t ret;

403

371

404

372

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

405

373

data buffer */

406

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

374

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

407

375

if(rc != GPG_ERR_NO_ERROR){

408

376

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

409

377

gpgme_strsource(rc), gpgme_strerror(rc));

410

378

plaintext_length = -1;

411

379

if(debug){

412

380

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

381

result = gpgme_op_decrypt_result(mc.ctx);

414

382

if(result == NULL){

415

383

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

416

384

} else {

493

461

return plaintext_length;

494

462

}

495

463

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);

464

static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

467

if(ret == NULL)

468

ret = "(unknown)";

469

return ret;

507

470

}

508

471

509

472

/* GnuTLS log function callback */

510

__attribute__((nonnull))

511

473

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

512

474

const char* string){

513

475

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

514

476

}

515

477

516

__attribute__((nonnull, warn_unused_result))

517

478

static int init_gnutls_global(const char *pubkeyfilename,

518

const char *seckeyfilename,

519

const char *dhparamsfilename,

520

mandos_context *mc){

479

const char *seckeyfilename){

521

480

int ret;

522

unsigned int uret;

523

481

524

482

if(debug){

525

483

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

541

499

}

542

500

543

501

/* OpenPGP credentials */

544

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

545

503

if(ret != GNUTLS_E_SUCCESS){

546

504

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

547

505

safer_gnutls_strerror(ret));

557

515

}

558

516

559

517

ret = gnutls_certificate_set_openpgp_key_file

560

(mc->cred, pubkeyfilename, seckeyfilename,

518

(mc.cred, pubkeyfilename, seckeyfilename,

561

519

GNUTLS_OPENPGP_FMT_BASE64);

562

520

if(ret != GNUTLS_E_SUCCESS){

563

521

fprintf_plus(stderr,

569

527

}

570

528

571

529

/* GnuTLS server initialization */

572

ret = gnutls_dh_params_init(&mc->dh_params);

530

ret = gnutls_dh_params_init(&mc.dh_params);

573

531

if(ret != GNUTLS_E_SUCCESS){

574

532

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

575

533

" initialization: %s\n",

576

534

safer_gnutls_strerror(ret));

577

535

goto globalfail;

578

536

}

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);

537

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

538

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

541

goto globalfail;

542

}

543

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

752

545

753

546

return 0;

754

547

755

548

globalfail:

756

549

757

gnutls_certificate_free_credentials(mc->cred);

550

gnutls_certificate_free_credentials(mc.cred);

758

551

gnutls_global_deinit();

759

gnutls_dh_params_deinit(mc->dh_params);

552

gnutls_dh_params_deinit(mc.dh_params);

760

553

return -1;

761

554

}

762

555

763

__attribute__((nonnull, warn_unused_result))

764

static int init_gnutls_session(gnutls_session_t *session,

765

mandos_context *mc){

556

static int init_gnutls_session(gnutls_session_t *session){

766

557

int ret;

767

558

/* GnuTLS session creation */

768

559

do {

780

571

{

781

572

const char *err;

782

573

do {

783

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

574

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

784

575

if(quit_now){

785

576

gnutls_deinit(*session);

786

577

return -1;

797

588

798

589

do {

799

590

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

800

mc->cred);

591

mc.cred);

801

592

if(quit_now){

802

593

gnutls_deinit(*session);

803

594

return -1;

813

604

/* ignore client certificate if any. */

814

605

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

815

606

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

608

816

609

return 0;

817

610

}

818

611

820

613

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

821

614

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

822

615

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

1041

616

/* Called when a Mandos server is found */

1042

__attribute__((nonnull, warn_unused_result))

1043

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

617

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

1044

618

AvahiIfIndex if_index,

1045

int af, mandos_context *mc){

619

int af){

1046

620

int ret, tcp_sd = -1;

1047

621

ssize_t sret;

1048

struct sockaddr_storage to;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

1049

626

char *buffer = NULL;

1050

627

char *decrypted_buffer = NULL;

1051

628

size_t buffer_length = 0;

1054

631

int retval = -1;

1055

632

gnutls_session_t session;

1056

633

int pf; /* Protocol family */

1057

bool route_added = false;

1058

634

1059

635

errno = 0;

1060

636

1076

652

return -1;

1077

653

}

1078

654

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

ret = init_gnutls_session(&session);

1112

656

if(ret != 0){

1113

657

return -1;

1114

658

}

1115

659

1116

660

if(debug){

1117

661

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

1118

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

662

PRIu16 "\n", ip, port);

1119

663

}

1120

664

1121

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

665

tcp_sd = socket(pf, SOCK_STREAM, 0);

1122

666

if(tcp_sd < 0){

1123

667

int e = errno;

1124

668

perror_plus("socket");

1131

675

goto mandos_end;

1132

676

}

1133

677

678

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

1134

679

if(af == AF_INET6){

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);

680

to.in6.sin6_family = (sa_family_t)af;

681

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

1138

682

} else { /* IPv4 */

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);

683

to.in.sin_family = (sa_family_t)af;

684

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

1142

685

}

1143

686

if(ret < 0 ){

1144

687

int e = errno;

1153

696

goto mandos_end;

1154

697

}

1155

698

if(af == AF_INET6){

1156

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

1157

if(IN6_IS_ADDR_LINKLOCAL

1158

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

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

1159

706

if(if_index == AVAHI_IF_UNSPEC){

1160

707

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

1161

708

" incomplete without a network interface\n");

1163

710

goto mandos_end;

1164

711

}

1165

712

/* Set the network interface number as scope */

1166

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

713

to.in6.sin6_scope_id = (uint32_t)if_index;

1167

714

}

1168

715

} else {

1169

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

716

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

717

-Wconversion and

718

-Wunreachable-code */

1170

719

}

1171

720

1172

721

if(quit_now){

1180

729

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

1181

730

perror_plus("if_indextoname");

1182

731

} else {

1183

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

1184

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

732

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

733

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

1185

734

}

1186

735

} else {

1187

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

1188

ip, (uintmax_t)port);

736

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

737

ip, port);

1189

738

}

1190

739

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1191

740

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

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;

741

const char *pcret;

742

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

745

} else {

746

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

747

sizeof(addrstr));

748

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

755

}

756

}

757

758

if(quit_now){

759

errno = EINTR;

760

goto mandos_end;

761

}

762

763

if(af == AF_INET6){

764

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

765

} else {

766

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

767

}

768

if(ret < 0){

769

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

770

int e = errno;

771

perror_plus("connect");

772

errno = e;

773

}

774

goto mandos_end;

775

}

776

777

if(quit_now){

778

errno = EINTR;

779

goto mandos_end;

1272

780

}

1273

781

1274

782

const char *out = mandos_protocol_version;

1310

818

goto mandos_end;

1311

819

}

1312

820

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);

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1318

823

1319

824

if(quit_now){

1320

825

errno = EINTR;

1425

930

if(buffer_length > 0){

1426

931

ssize_t decrypted_buffer_size;

1427

932

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1428

&decrypted_buffer, mc);

933

&decrypted_buffer);

1429

934

if(decrypted_buffer_size >= 0){

1430

935

1431

936

written = 0;

1457

962

1458

963

mandos_end:

1459

964

{

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

}

1466

965

int e = errno;

1467

966

free(decrypted_buffer);

1468

967

free(buffer);

1469

968

if(tcp_sd >= 0){

1470

ret = close(tcp_sd);

969

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

1471

970

}

1472

971

if(ret == -1){

1473

972

if(e == 0){

1485

984

return retval;

1486

985

}

1487

986

1488

__attribute__((nonnull))

1489

987

static void resolve_callback(AvahiSServiceResolver *r,

1490

988

AvahiIfIndex interface,

1491

989

AvahiProtocol proto,

1499

997

AVAHI_GCC_UNUSED AvahiStringList *txt,

1500

998

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1501

999

flags,

1502

void *mc){

1503

if(r == NULL){

1504

return;

1505

}

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1506

1002

1507

1003

/* Called whenever a service has been resolved successfully or

1508

1004

timed out */

1509

1005

1510

1006

if(quit_now){

1511

avahi_s_service_resolver_free(r);

1512

1007

return;

1513

1008

}

1514

1009

1518

1013

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

1519

1014

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

1520

1015

domain,

1521

avahi_strerror(avahi_server_errno

1522

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

1016

avahi_strerror(avahi_server_errno(mc.server)));

1523

1017

break;

1524

1018

1525

1019

case AVAHI_RESOLVER_FOUND:

1531

1025

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

1532

1026

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

1533

1027

}

1534

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

1535

interface,

1536

avahi_proto_to_af(proto),

1537

mc);

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1538

1030

if(ret == 0){

1539

avahi_simple_poll_quit(simple_poll);

1031

avahi_simple_poll_quit(mc.simple_poll);

1540

1032

} else {

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

}

1033

ret = add_server(ip, port, interface,

1034

avahi_proto_to_af(proto));

1547

1035

}

1548

1036

}

1549

1037

}

1559

1047

const char *domain,

1560

1048

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1561

1049

flags,

1562

void *mc){

1563

if(b == NULL){

1564

return;

1565

}

1050

AVAHI_GCC_UNUSED void* userdata){

1051

assert(b);

1566

1052

1567

1053

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

1568

1054

is removed from the LAN */

1576

1062

case AVAHI_BROWSER_FAILURE:

1577

1063

1578

1064

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

1579

avahi_strerror(avahi_server_errno

1580

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

1581

avahi_simple_poll_quit(simple_poll);

1065

avahi_strerror(avahi_server_errno(mc.server)));

1066

avahi_simple_poll_quit(mc.simple_poll);

1582

1067

return;

1583

1068

1584

1069

case AVAHI_BROWSER_NEW:

1587

1072

the callback function is called the Avahi server will free the

1588

1073

resolver for us. */

1589

1074

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)

1075

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

1076

name, type, domain, protocol, 0,

1077

resolve_callback, NULL) == NULL)

1594

1078

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

1595

1079

" %s\n", name,

1596

avahi_strerror(avahi_server_errno

1597

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

1598

1081

break;

1599

1082

1600

1083

case AVAHI_BROWSER_REMOVE:

1619

1102

signal_received = sig;

1620

1103

int old_errno = errno;

1621

1104

/* set main loop to exit */

1622

if(simple_poll != NULL){

1623

avahi_simple_poll_quit(simple_poll);

1105

if(mc.simple_poll != NULL){

1106

avahi_simple_poll_quit(mc.simple_poll);

1624

1107

}

1625

1108

errno = old_errno;

1626

1109

}

1627

1110

1628

__attribute__((nonnull, warn_unused_result))

1629

1111

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

1630

1112

int ret;

1631

error_t ret_errno;

1632

1113

1633

1114

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

1634

1115

if(s < 0){

1635

ret_errno = errno;

1636

1116

perror_plus("socket");

1637

errno = ret_errno;

1638

1117

return false;

1639

1118

}

1640

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

1641

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

1119

strcpy(ifr->ifr_name, ifname);

1642

1120

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1643

1121

if(ret == -1){

1644

1122

if(debug){

1645

ret_errno = errno;

1646

1123

perror_plus("ioctl SIOCGIFFLAGS");

1647

errno = ret_errno;

1648

1124

}

1649

1125

return false;

1650

1126

}

1651

1127

return true;

1652

1128

}

1653

1129

1654

__attribute__((nonnull, warn_unused_result))

1655

1130

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

1656

1131

1657

1132

/* Reject the loopback device */

1699

1174

* corresponds to an acceptable network device.

1700

1175

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

1701

1176

*/

1702

__attribute__((nonnull, warn_unused_result))

1703

1177

int good_interface(const struct dirent *if_entry){

1704

1178

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

1705

1179

return 0;

1721

1195

}

1722

1196

1723

1197

/*

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))

1198

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

1199

* corresponds to an acceptable network device which is up.

1200

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

1201

*/

1202

int up_interface(const struct dirent *if_entry){

1203

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

1204

return 0;

1205

}

1206

1207

struct ifreq ifr;

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return 0;

1214

}

1215

1216

/* Reject down interfaces */

1217

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

1218

if(debug){

1219

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

1220

if_entry->d_name);

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject non-running interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

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

1235

return 0;

1236

}

1237

return 1;

1238

}

1239

1758

1240

int notdotentries(const struct dirent *direntry){

1759

1241

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

1760

1242

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

1767

1249

}

1768

1250

1769

1251

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

1770

__attribute__((nonnull, warn_unused_result))

1771

1252

int runnable_hook(const struct dirent *direntry){

1772

1253

int ret;

1773

1254

size_t sret;

1781

1262

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

1782

1263

"abcdefghijklmnopqrstuvwxyz"

1783

1264

"0123456789"

1784

"_.-");

1265

"_-");

1785

1266

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

1786

1267

/* Contains non-allowed characters */

1787

1268

if(debug){

1791

1272

return 0;

1792

1273

}

1793

1274

1794

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

1275

char *fullname = NULL;

1276

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

1277

if(ret < 0){

1278

perror_plus("asprintf");

1279

return 0;

1280

}

1281

1282

ret = stat(fullname, &st);

1795

1283

if(ret == -1){

1796

1284

if(debug){

1797

1285

perror_plus("Could not stat hook");

1821

1309

return 1;

1822

1310

}

1823

1311

1824

__attribute__((nonnull, warn_unused_result))

1825

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1826

mandos_context *mc){

1312

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1827

1313

int ret;

1828

1314

struct timespec now;

1829

1315

struct timespec waited_time;

1830

1316

intmax_t block_time;

1831

1317

1832

1318

while(true){

1833

if(mc->current_server == NULL){

1834

if(debug){

1319

if(mc.current_server == NULL){

1320

if (debug){

1835

1321

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

1836

1322

" No timeout!\n");

1837

1323

}

1838

1324

ret = avahi_simple_poll_iterate(s, -1);

1839

1325

} else {

1840

if(debug){

1326

if (debug){

1841

1327

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

1842

1328

" it, or wait\n");

1843

1329

}

1850

1336

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

1851

1337

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

1852

1338

waited_time.tv_sec = (now.tv_sec

1853

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

1339

- mc.current_server->last_seen.tv_sec);

1854

1340

waited_time.tv_nsec = (now.tv_nsec

1855

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

1341

- mc.current_server->last_seen.tv_nsec);

1856

1342

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

1857

1343

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

1858

1344

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

1860

1346

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

1861

1347

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

1862

1348

1863

if(debug){

1349

if (debug){

1864

1350

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

1865

1351

block_time);

1866

1352

}

1867

1353

1868

1354

if(block_time <= 0){

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);

1355

ret = start_mandos_communication(mc.current_server->ip,

1356

mc.current_server->port,

1357

mc.current_server->if_index,

1358

mc.current_server->af);

1873

1359

if(ret == 0){

1874

avahi_simple_poll_quit(s);

1360

avahi_simple_poll_quit(mc.simple_poll);

1875

1361

return 0;

1876

1362

}

1877

1363

ret = clock_gettime(CLOCK_MONOTONIC,

1878

&mc->current_server->last_seen);

1364

&mc.current_server->last_seen);

1879

1365

if(ret == -1){

1880

1366

perror_plus("clock_gettime");

1881

1367

return -1;

1882

1368

}

1883

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

1369

mc.current_server = mc.current_server->next;

1884

1370

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

1885

1371

servers, but don't block */

1886

1372

}

1888

1374

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

1889

1375

}

1890

1376

if(ret != 0){

1891

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

1377

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

1892

1378

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

1893

1379

}

1894

1380

}

1895

1381

}

1896

1382

}

1897

1383

1898

__attribute__((nonnull))

1899

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

1384

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

1900

1385

const float delay){

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__ */

1386

struct dirent **direntries;

1387

struct dirent *direntry;

1388

int ret;

1389

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

1390

alphasort);

1929

1391

if(numhooks == -1){

1930

1392

perror_plus("scandir");

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){

1393

} else {

1394

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

1395

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

1396

direntry = direntries[i];

1397

char *fullname = NULL;

1398

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

1399

if(ret < 0){

1992

1400

perror_plus("asprintf");

1993

_exit(EX_OSERR);

1994

}

1995

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

1996

if(ret == -1){

1401

continue;

1402

}

1403

if(debug){

1404

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

1405

direntry->d_name);

1406

}

1407

pid_t hook_pid = fork();

1408

if(hook_pid == 0){

1409

/* Child */

1410

/* Raise privileges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror_plus("seteuid");

1415

}

1416

/* Raise privileges even more */

1417

errno = 0;

1418

ret = setuid(0);

1419

if(ret == -1){

1420

perror_plus("setuid");

1421

}

1422

/* Set group */

1423

errno = 0;

1424

ret = setgid(0);

1425

if(ret == -1){

1426

perror_plus("setgid");

1427

}

1428

/* Reset supplementary groups */

1429

errno = 0;

1430

ret = setgroups(0, NULL);

1431

if(ret == -1){

1432

perror_plus("setgroups");

1433

}

1434

dup2(devnull, STDIN_FILENO);

1435

close(devnull);

1436

dup2(STDERR_FILENO, STDOUT_FILENO);

1437

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

1438

if(ret == -1){

1439

perror_plus("setenv");

1440

_exit(EX_OSERR);

1441

}

1442

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

1443

if(ret == -1){

1444

perror_plus("setenv");

1445

_exit(EX_OSERR);

1446

}

1447

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

1448

if(ret == -1){

1449

perror_plus("setenv");

1450

_exit(EX_OSERR);

1451

}

1452

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

1453

if(ret == -1){

1454

perror_plus("setenv");

1455

_exit(EX_OSERR);

1456

}

1457

char *delaystring;

1458

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

1459

if(ret == -1){

1460

perror_plus("asprintf");

1461

_exit(EX_OSERR);

1462

}

1463

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

1464

if(ret == -1){

1465

free(delaystring);

1466

perror_plus("setenv");

1467

_exit(EX_OSERR);

1468

}

1997

1469

free(delaystring);

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;

1470

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

1471

perror_plus("execl");

1472

} else {

1473

int status;

1474

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

1475

perror_plus("waitpid");

1476

free(fullname);

1477

continue;

1478

}

1479

if(WIFEXITED(status)){

1480

if(WEXITSTATUS(status) != 0){

1481

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

1482

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

1483

WEXITSTATUS(status));

1484

free(fullname);

1485

continue;

1486

}

1487

} else if(WIFSIGNALED(status)){

1488

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

1489

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

1490

WTERMSIG(status));

1491

free(fullname);

1492

continue;

1493

} else {

1494

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

1495

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

1496

free(fullname);

1497

continue;

1498

}

1499

}

1500

free(fullname);

1501

if(debug){

1502

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

1503

direntry->d_name);

1504

}

1505

}

1506

close(devnull);

1507

}

1508

return true;

2288

1509

}

2289

1510

2290

1511

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 };

2296

1512

AvahiSServiceBrowser *sb = NULL;

2297

error_t ret_errno;

1513

int error;

2298

1514

int ret;

2299

1515

intmax_t tmpmax;

2300

1516

char *tmp;

2301

1517

int exitcode = EXIT_SUCCESS;

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;

1518

const char *interface = "";

1519

struct ifreq network;

1520

int sd = -1;

1521

bool take_down_interface = false;

1522

uid_t uid;

1523

gid_t gid;

1524

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

1525

bool tempdir_created = false;

2307

1526

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2308

1527

const char *seckey = PATHDIR "/" SECKEY;

2309

1528

const char *pubkey = PATHDIR "/" PUBKEY;

2310

const char *dh_params_file = NULL;

2311

char *interfaces_hooks = NULL;

2312

1529

2313

1530

bool gnutls_initialized = false;

2314

1531

bool gpgme_initialized = false;

2366

1583

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

2367

1584

" Diffie-Hellman key exchange",

2368

1585

.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 },

2374

1586

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

2375

1587

.arg = "STRING",

2376

1588

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

2381

1593

.group = 2 },

2382

1594

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

2383

1595

.arg = "SECONDS",

2384

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

1596

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

2385

1597

.group = 2 },

2386

1598

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

2387

1599

.arg = "DIR",

2410

1622

connect_to = arg;

2411

1623

break;

2412

1624

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

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

}

1625

interface = arg;

2418

1626

break;

2419

1627

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

2420

1628

seckey = arg;

2431

1639

}

2432

1640

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

2433

1641

break;

2434

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

2435

dh_params_file = arg;

2436

break;

2437

1642

case 130: /* --priority */

2438

1643

mc.priority = arg;

2439

1644

break;

2466

1671

argp_state_help(state, state->out_stream,

2467

1672

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2468

1673

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

1674

fprintf_plus(state->out_stream,

1675

"Mandos plugin mandos-client: ");

2469

1676

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

2470

1677

exit(argp_err_exit_status);

2471

1678

break;

2495

1702

goto end;

2496

1703

}

2497

1704

}

2498

1705

2499

1706

{

2500

1707

/* Work around Debian bug #633582:

2501

1708

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

2502

1709

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");

1710

/* Re-raise priviliges */

1711

errno = 0;

1712

ret = seteuid(0);

1713

if(ret == -1){

1714

perror_plus("seteuid");

2508

1715

} else {

2509

1716

struct stat st;

2510

1717

2525

1732

}

2526

1733

}

2527

1734

}

2528

close(seckey_fd);

1735

TEMP_FAILURE_RETRY(close(seckey_fd));

2529

1736

}

2530

1737

}

2531

1738

2532

1739

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

2533

1740

int pubkey_fd = open(pubkey, O_RDONLY);

2534

1741

if(pubkey_fd == -1){

2546

1753

}

2547

1754

}

2548

1755

}

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

1756

TEMP_FAILURE_RETRY(close(pubkey_fd));

1757

}

1758

}

1759

2575

1760

/* 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;

1761

errno = 0;

1762

ret = seteuid(uid);

1763

if(ret == -1){

1764

perror_plus("seteuid");

2597

1765

}

2598

1766

}

2599

1767

}

2600

1768

2601

1769

/* Run network hooks */

2602

{

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);

1770

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

1771

goto end;

2614

1772

}

2615

1773

2616

1774

if(not debug){

2617

1775

avahi_set_log_function(empty_log);

2618

1776

}

2619

1777

1778

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

1779

struct dirent **direntries;

1780

/* First look for interfaces that are up */

1781

ret = scandir(sys_class_net, &direntries, up_interface,

1782

alphasort);

1783

if(ret == 0){

1784

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

1785

free(direntries);

1786

ret = scandir(sys_class_net, &direntries, good_interface,

1787

alphasort);

1788

}

1789

if(ret >= 1){

1790

/* Pick the first interface returned */

1791

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

1792

if(debug){

1793

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

1794

}

1795

if(interface == NULL){

1796

perror_plus("malloc");

1797

free(direntries);

1798

exitcode = EXIT_FAILURE;

1799

goto end;

1800

}

1801

free(direntries);

1802

} else {

1803

free(direntries);

1804

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

1805

exitcode = EXIT_FAILURE;

1806

goto end;

1807

}

1808

}

1809

2620

1810

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

2621

1811

from the signal handler */

2622

1812

/* Initialize the pseudo-RNG for Avahi */

2623

1813

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

2624

simple_poll = avahi_simple_poll_new();

2625

if(simple_poll == NULL){

1814

mc.simple_poll = avahi_simple_poll_new();

1815

if(mc.simple_poll == NULL){

2626

1816

fprintf_plus(stderr,

2627

1817

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

2628

1818

exitcode = EX_UNAVAILABLE;

2692

1882

}

2693

1883

}

2694

1884

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;

1885

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

1886

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

1887

if_index = (AvahiIfIndex) if_nametoindex(interface);

1888

if(if_index == 0){

1889

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

1890

exitcode = EX_UNAVAILABLE;

1891

goto end;

1892

}

1893

1894

if(quit_now){

1895

goto end;

1896

}

1897

1898

/* Re-raise priviliges */

1899

errno = 0;

1900

ret = seteuid(0);

1901

if(ret == -1){

1902

perror_plus("seteuid");

1903

}

1904

1905

#ifdef __linux__

1906

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1907

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

1908

ret = klogctl(8, NULL, 5);

1909

bool restore_loglevel = true;

1910

if(ret == -1){

1911

restore_loglevel = false;

1912

perror_plus("klogctl");

1913

}

1914

#endif /* __linux__ */

1915

1916

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1917

if(sd < 0){

1918

perror_plus("socket");

1919

exitcode = EX_OSERR;

1920

#ifdef __linux__

1921

if(restore_loglevel){

1922

ret = klogctl(7, NULL, 0);

1923

if(ret == -1){

1924

perror_plus("klogctl");

1925

}

1926

}

1927

#endif /* __linux__ */

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

strcpy(network.ifr_name, interface);

1937

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

1938

if(ret == -1){

1939

perror_plus("ioctl SIOCGIFFLAGS");

1940

#ifdef __linux__

1941

if(restore_loglevel){

1942

ret = klogctl(7, NULL, 0);

1943

if(ret == -1){

1944

perror_plus("klogctl");

1945

}

1946

}

1947

#endif /* __linux__ */

1948

exitcode = EX_OSERR;

1949

/* Lower privileges */

1950

errno = 0;

1951

ret = seteuid(uid);

1952

if(ret == -1){

1953

perror_plus("seteuid");

1954

}

1955

goto end;

1956

}

1957

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

1958

network.ifr_flags |= IFF_UP;

1959

take_down_interface = true;

1960

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

1961

if(ret == -1){

1962

take_down_interface = false;

1963

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1964

exitcode = EX_OSERR;

1965

#ifdef __linux__

1966

if(restore_loglevel){

1967

ret = klogctl(7, NULL, 0);

1968

if(ret == -1){

1969

perror_plus("klogctl");

2746

1970

}

2747

1971

}

1972

#endif /* __linux__ */

1973

/* Lower privileges */

1974

errno = 0;

1975

ret = seteuid(uid);

1976

if(ret == -1){

1977

perror_plus("seteuid");

1978

}

1979

goto end;

1980

}

1981

}

1982

/* Sleep checking until interface is running.

1983

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

1984

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

1985

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

1986

if(ret == -1){

1987

perror_plus("ioctl SIOCGIFFLAGS");

1988

} else if(network.ifr_flags & IFF_RUNNING){

2748

1989

break;

2749

1990

}

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);

1991

struct timespec sleeptime = { .tv_nsec = 250000000 };

1992

ret = nanosleep(&sleeptime, NULL);

1993

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

1994

perror_plus("nanosleep");

1995

}

1996

}

1997

if(not take_down_interface){

1998

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

1999

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

2000

if(ret == -1){

2001

perror_plus("close");

2002

}

2003

}

2004

#ifdef __linux__

2005

if(restore_loglevel){

2006

/* Restores kernel loglevel to default */

2007

ret = klogctl(7, NULL, 0);

2008

if(ret == -1){

2009

perror_plus("klogctl");

2010

}

2011

}

2012

#endif /* __linux__ */

2013

/* Lower privileges */

2014

errno = 0;

2015

/* Lower privileges */

2016

ret = seteuid(uid);

2017

if(ret == -1){

2018

perror_plus("seteuid");

2019

}

2778

2020

}

2779

2021

2780

2022

if(quit_now){

2781

2023

goto end;

2782

2024

}

2783

2025

2784

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

2026

ret = init_gnutls_global(pubkey, seckey);

2785

2027

if(ret == -1){

2786

2028

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

2787

2029

exitcode = EX_UNAVAILABLE;

2794

2036

goto end;

2795

2037

}

2796

2038

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){

2039

if(mkdtemp(tempdir) == NULL){

2807

2040

perror_plus("mkdtemp");

2808

2041

goto end;

2809

2042

}

2043

tempdir_created = true;

2810

2044

2811

2045

if(quit_now){

2812

2046

goto end;

2813

2047

}

2814

2048

2815

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

2049

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

2816

2050

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

2817

2051

exitcode = EX_UNAVAILABLE;

2818

2052

goto end;

2828

2062

/* Connect directly, do not use Zeroconf */

2829

2063

/* (Mainly meant for debugging) */

2830

2064

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

2831

2832

2065

if(address == NULL){

2833

2066

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

2834

2067

exitcode = EX_USAGE;

2839

2072

goto end;

2840

2073

}

2841

2074

2842

in_port_t port;

2075

uint16_t port;

2843

2076

errno = 0;

2844

2077

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

2845

2078

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

2846

or tmpmax != (in_port_t)tmpmax){

2079

or tmpmax != (uint16_t)tmpmax){

2847

2080

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

2848

2081

exitcode = EX_USAGE;

2849

2082

goto end;

2850

2083

}

2851

2084

2852

2085

if(quit_now){

2853

2086

goto end;

2854

2087

}

2855

2088

2856

port = (in_port_t)tmpmax;

2089

port = (uint16_t)tmpmax;

2857

2090

*address = '\0';

2858

2091

/* Colon in address indicates IPv6 */

2859

2092

int af;

2875

2108

}

2876

2109

2877

2110

while(not quit_now){

2878

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

2879

&mc);

2111

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

2880

2112

if(quit_now or ret == 0){

2881

2113

break;

2882

2114

}

2884

2116

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

2885

2117

(int)retry_interval);

2886

2118

}

2887

sleep((unsigned int)retry_interval);

2119

sleep((int)retry_interval);

2888

2120

}

2889

2121

2890

if(not quit_now){

2122

if (not quit_now){

2891

2123

exitcode = EXIT_SUCCESS;

2892

2124

}

2893

2125

2908

2140

config.publish_domain = 0;

2909

2141

2910

2142

/* Allocate a new server */

2911

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2912

&config, NULL, NULL, &ret_errno);

2143

mc.server = avahi_server_new(avahi_simple_poll_get

2144

(mc.simple_poll), &config, NULL,

2145

NULL, &error);

2913

2146

2914

2147

/* Free the Avahi configuration data */

2915

2148

avahi_server_config_free(&config);

2918

2151

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

2919

2152

if(mc.server == NULL){

2920

2153

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

2921

avahi_strerror(ret_errno));

2154

avahi_strerror(error));

2922

2155

exitcode = EX_UNAVAILABLE;

2923

2156

goto end;

2924

2157

}

2930

2163

/* Create the Avahi service browser */

2931

2164

sb = avahi_s_service_browser_new(mc.server, if_index,

2932

2165

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2933

NULL, 0, browse_callback,

2934

(void *)&mc);

2166

NULL, 0, browse_callback, NULL);

2935

2167

if(sb == NULL){

2936

2168

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

2937

2169

avahi_strerror(avahi_server_errno(mc.server)));

2948

2180

if(debug){

2949

2181

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

2950

2182

}

2951

2952

ret = avahi_loop_with_timeout(simple_poll,

2953

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

2183

2184

ret = avahi_loop_with_timeout(mc.simple_poll,

2185

(int)(retry_interval * 1000));

2954

2186

if(debug){

2955

2187

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

2956

2188

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

2963

2195

}

2964

2196

2965

2197

/* Cleanup things */

2966

free(mc.interfaces);

2967

2968

2198

if(sb != NULL)

2969

2199

avahi_s_service_browser_free(sb);

2970

2200

2971

2201

if(mc.server != NULL)

2972

2202

avahi_server_free(mc.server);

2973

2203

2974

if(simple_poll != NULL)

2975

avahi_simple_poll_free(simple_poll);

2204

if(mc.simple_poll != NULL)

2205

avahi_simple_poll_free(mc.simple_poll);

2976

2206

2977

2207

if(gnutls_initialized){

2978

2208

gnutls_certificate_free_credentials(mc.cred);

2990

2220

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

2991

2221

while(mc.current_server != NULL){

2992

2222

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

3001

2223

free(mc.current_server);

3002

2224

mc.current_server = next;

3003

2225

}

3004

2226

}

3005

2227

3006

/* Re-raise privileges */

2228

/* Run network hooks */

2229

run_network_hooks("stop", interface, delay);

2230

2231

/* Re-raise priviliges */

3007

2232

{

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

}

2233

errno = 0;

2234

ret = seteuid(0);

2235

if(ret == -1){

2236

perror_plus("seteuid");

3035

2237

}

3036

2238

3037

ret_errno = lower_privileges_permanently();

3038

if(ret_errno != 0){

3039

errno = ret_errno;

3040

perror_plus("Failed to lower privileges permanently");

2239

/* Take down the network interface */

2240

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

2241

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

2242

if(ret == -1){

2243

perror_plus("ioctl SIOCGIFFLAGS");

2244

} else if(network.ifr_flags & IFF_UP){

2245

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

2246

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

2247

if(ret == -1){

2248

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2249

}

2250

}

2251

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

2252

if(ret == -1){

2253

perror_plus("close");

2254

}

3041

2255

}

3042

2256

}

3043

3044

free(interfaces_to_take_down);

3045

free(interfaces_hooks);

2257

/* Lower privileges permanently */

2258

errno = 0;

2259

ret = setuid(uid);

2260

if(ret == -1){

2261

perror_plus("setuid");

2262

}

3046

2263

3047

2264

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

3048

if(tempdir != NULL){

2265

if(tempdir_created){

3049

2266

struct dirent **direntries = NULL;

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

}

2267

struct dirent *direntry = NULL;

2268

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

2269

alphasort);

2270

if (numentries > 0){

2271

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

2272

direntry = direntries[i];

2273

char *fullname = NULL;

2274

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

2275

direntry->d_name);

2276

if(ret < 0){

2277

perror_plus("asprintf");

2278

continue;

2279

}

2280

ret = remove(fullname);

2281

if(ret == -1){

2282

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

2283

strerror(errno));

2284

}

2285

free(fullname);

3089

2286

}

3090

close(tempdir_fd);

2287

}

2288

2289

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

2290

free(direntries);

2291

if (numentries == -1){

2292

perror_plus("scandir");

2293

}

2294

ret = rmdir(tempdir);

2295

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

2296

perror_plus("rmdir");

3091

2297

}

3092

2298

}

3093

2299