/mandos/trunk : revision 678

9

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

10

*

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* Everything else is

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13

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*

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

16

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

55

opendir(), DIR */

56

#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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inet_pton(), connect(),

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getnameinfo() */

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

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61

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

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62

*/

62

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

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strtoimax() */

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

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

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program_invocation_short_name */

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

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

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

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

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

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

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

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

130

136

131

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bool debug = false;

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138

static const char mandos_protocol_version[] = "1";

133

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

134

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

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

140

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

135

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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

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typedef struct server{

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const char *ip;

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uint16_t port;

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in_port_t port;

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AvahiIfIndex if_index;

146

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int af;

147

153

struct timespec last_seen;

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157

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

153

159

typedef struct {

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AvahiSimplePoll *simple_poll;

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160

AvahiServer *server;

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161

gnutls_certificate_credentials_t cred;

157

162

unsigned int dh_bits;

159

164

const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

168

size_t interfaces_size;

162

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} mandos_context;

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170

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

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

166

.dh_bits = 1024, .priority = "SECURE256"

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

168

.current_server = NULL };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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173

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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183

perror(print_text);

180

184

}

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185

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

186

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

183

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

184

188

va_list ap;

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va_start (ap, format);

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190

187

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

188

192

program_invocation_short_name));

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

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

190

194

}

191

195

192

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/*

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198

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

199

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

201

if(buffer == NULL){

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

206

if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

209

errno = old_errno;

210

*buffer = NULL;

202

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return 0;

203

212

}

213

*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

206

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return buffer_capacity;

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217

}

208

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

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

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int af){

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

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

214

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if(new_server == NULL){

223

234

perror_plus("strdup");

224

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return false;

225

236

}

237

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

240

return false;

241

}

226

242

/* Special case of first server */

227

if (mc.current_server == NULL){

243

if(*current_server == NULL){

228

244

new_server->next = new_server;

229

245

new_server->prev = new_server;

230

mc.current_server = new_server;

231

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

246

*current_server = new_server;

232

247

} else {

233

new_server->next = mc.current_server;

234

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

248

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

249

new_server->next = *current_server;

250

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

235

251

new_server->prev->next = new_server;

236

mc.current_server->prev = new_server;

237

}

238

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

239

if(ret == -1){

240

perror_plus("clock_gettime");

241

return false;

252

(*current_server)->prev = new_server;

242

253

}

243

254

return true;

244

255

}

246

257

/*

247

258

* Initialize GPGME.

248

259

*/

249

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

250

const char *tempdir){

260

__attribute__((nonnull, warn_unused_result))

261

static bool init_gpgme(const char * const seckey,

262

const char * const pubkey,

263

const char * const tempdir,

264

mandos_context *mc){

251

265

gpgme_error_t rc;

252

266

gpgme_engine_info_t engine_info;

253

267

254

255

268

/*

256

269

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

257

270

*/

258

bool import_key(const char *filename){

271

bool import_key(const char * const filename){

259

272

int ret;

260

273

int fd;

261

274

gpgme_data_t pgp_data;

273

286

return false;

274

287

}

275

288

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rc = gpgme_op_import(mc.ctx, pgp_data);

289

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

277

290

if(rc != GPG_ERR_NO_ERROR){

278

291

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

279

292

gpgme_strsource(rc), gpgme_strerror(rc));

323

336

}

324

337

325

338

/* Create new GPGME "context" */

326

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

339

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

327

340

if(rc != GPG_ERR_NO_ERROR){

328

341

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

329

342

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

342

355

* Decrypt OpenPGP data.

343

356

* Returns -1 on error

344

357

*/

358

__attribute__((nonnull, warn_unused_result))

345

359

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

360

size_t crypto_size,

347

char **plaintext){

361

char **plaintext,

362

mandos_context *mc){

348

363

gpgme_data_t dh_crypto, dh_plain;

349

364

gpgme_error_t rc;

350

365

ssize_t ret;

376

391

377

392

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

378

393

data buffer */

379

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

394

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

380

395

if(rc != GPG_ERR_NO_ERROR){

381

396

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

382

397

gpgme_strsource(rc), gpgme_strerror(rc));

383

398

plaintext_length = -1;

384

399

if(debug){

385

400

gpgme_decrypt_result_t result;

386

result = gpgme_op_decrypt_result(mc.ctx);

401

result = gpgme_op_decrypt_result(mc->ctx);

387

402

if(result == NULL){

388

403

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

389

404

} else {

466

481

return plaintext_length;

467

482

}

468

483

469

static const char * safer_gnutls_strerror(int value){

470

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

471

-Wunreachable-code */

484

__attribute__((warn_unused_result))

485

static const char *safer_gnutls_strerror(int value){

486

const char *ret = gnutls_strerror(value);

472

487

if(ret == NULL)

473

488

ret = "(unknown)";

474

489

return ret;

475

490

}

476

491

477

492

/* GnuTLS log function callback */

493

__attribute__((nonnull))

478

494

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

479

495

const char* string){

480

496

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

481

497

}

482

498

499

__attribute__((nonnull, warn_unused_result))

483

500

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename){

501

const char *seckeyfilename,

502

mandos_context *mc){

485

503

int ret;

486

504

487

505

if(debug){

504

522

}

505

523

506

524

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

525

ret = gnutls_certificate_allocate_credentials(&mc->cred);

508

526

if(ret != GNUTLS_E_SUCCESS){

509

527

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

510

528

safer_gnutls_strerror(ret));

520

538

}

521

539

522

540

ret = gnutls_certificate_set_openpgp_key_file

523

(mc.cred, pubkeyfilename, seckeyfilename,

541

(mc->cred, pubkeyfilename, seckeyfilename,

524

542

GNUTLS_OPENPGP_FMT_BASE64);

525

543

if(ret != GNUTLS_E_SUCCESS){

526

544

fprintf_plus(stderr,

532

550

}

533

551

534

552

/* GnuTLS server initialization */

535

ret = gnutls_dh_params_init(&mc.dh_params);

553

ret = gnutls_dh_params_init(&mc->dh_params);

536

554

if(ret != GNUTLS_E_SUCCESS){

537

555

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

556

" initialization: %s\n",

539

557

safer_gnutls_strerror(ret));

540

558

goto globalfail;

541

559

}

542

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

560

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

543

561

if(ret != GNUTLS_E_SUCCESS){

544

562

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

545

563

safer_gnutls_strerror(ret));

546

564

goto globalfail;

547

565

}

548

566

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

567

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

550

568

551

569

return 0;

552

570

553

571

globalfail:

554

572

555

gnutls_certificate_free_credentials(mc.cred);

573

gnutls_certificate_free_credentials(mc->cred);

556

574

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

575

gnutls_dh_params_deinit(mc->dh_params);

558

576

return -1;

559

577

}

560

578

561

static int init_gnutls_session(gnutls_session_t *session){

579

__attribute__((nonnull, warn_unused_result))

580

static int init_gnutls_session(gnutls_session_t *session,

581

mandos_context *mc){

562

582

int ret;

563

583

/* GnuTLS session creation */

564

584

do {

576

596

{

577

597

const char *err;

578

598

do {

579

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

599

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

580

600

if(quit_now){

581

601

gnutls_deinit(*session);

582

602

return -1;

593

613

594

614

do {

595

615

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

616

mc->cred);

597

617

if(quit_now){

598

618

gnutls_deinit(*session);

599

619

return -1;

609

629

/* ignore client certificate if any. */

610

630

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

631

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

613

633

614

634

return 0;

615

635

}

619

639

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

620

640

621

641

/* Called when a Mandos server is found */

622

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

642

__attribute__((nonnull, warn_unused_result))

643

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

623

644

AvahiIfIndex if_index,

624

int af){

645

int af, mandos_context *mc){

625

646

int ret, tcp_sd = -1;

626

647

ssize_t sret;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

648

struct sockaddr_storage to;

631

649

char *buffer = NULL;

632

650

char *decrypted_buffer = NULL;

633

651

size_t buffer_length = 0;

657

675

return -1;

658

676

}

659

677

660

ret = init_gnutls_session(&session);

678

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

679

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

680

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

681

bool match = false;

682

{

683

char *interface = NULL;

684

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

685

interface))){

686

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

687

match = true;

688

break;

689

}

690

}

691

}

692

if(not match){

693

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

694

connect to the server */

695

if(debug){

696

char interface[IF_NAMESIZE];

697

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

698

perror_plus("if_indextoname");

699

} else {

700

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

701

" \"%s\"\n",

702

if_indextoname((unsigned int)if_index,

703

interface));

704

}

705

}

706

return -1;

707

}

708

}

709

710

ret = init_gnutls_session(&session, mc);

661

711

if(ret != 0){

662

712

return -1;

663

713

}

664

714

665

715

if(debug){

666

716

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

667

PRIu16 "\n", ip, port);

717

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

668

718

}

669

719

670

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

682

732

683

733

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

684

734

if(af == AF_INET6){

685

to.in6.sin6_family = (sa_family_t)af;

686

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

735

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

736

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

687

737

} else { /* IPv4 */

688

to.in.sin_family = (sa_family_t)af;

689

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

738

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

739

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

690

740

}

691

741

if(ret < 0 ){

692

742

int e = errno;

701

751

goto mandos_end;

702

752

}

703

753

if(af == AF_INET6){

704

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

705

-Wconversion and

706

-Wunreachable-code */

707

708

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

709

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

710

-Wunreachable-code*/

754

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

755

if(IN6_IS_ADDR_LINKLOCAL

756

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

711

757

if(if_index == AVAHI_IF_UNSPEC){

712

758

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

713

759

" incomplete without a network interface\n");

715

761

goto mandos_end;

716

762

}

717

763

/* Set the network interface number as scope */

718

to.in6.sin6_scope_id = (uint32_t)if_index;

764

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

719

765

}

720

766

} else {

721

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

722

-Wconversion and

723

-Wunreachable-code */

767

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

724

768

}

725

769

726

770

if(quit_now){

734

778

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

735

779

perror_plus("if_indextoname");

736

780

} else {

737

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

738

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

781

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

782

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

739

783

}

740

784

} else {

741

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

742

ip, port);

785

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

786

ip, (uintmax_t)port);

743

787

}

744

788

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

745

789

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

746

const char *pcret;

747

790

if(af == AF_INET6){

748

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

749

sizeof(addrstr));

791

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

792

sizeof(struct sockaddr_in6),

793

addrstr, sizeof(addrstr), NULL, 0,

794

NI_NUMERICHOST);

750

795

} else {

751

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

752

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

753

800

}

754

if(pcret == NULL){

755

perror_plus("inet_ntop");

756

} else {

757

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

758

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

759

}

801

if(ret == EAI_SYSTEM){

802

perror_plus("getnameinfo");

803

} else if(ret != 0) {

804

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

805

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

806

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

760

807

}

761

808

}

762

809

766

813

}

767

814

768

815

if(af == AF_INET6){

769

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

816

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

817

sizeof(struct sockaddr_in6));

770

818

} else {

771

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

819

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

820

sizeof(struct sockaddr_in));

772

821

}

773

822

if(ret < 0){

774

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

823

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

775

824

int e = errno;

776

825

perror_plus("connect");

777

826

errno = e;

938

987

if(buffer_length > 0){

939

988

ssize_t decrypted_buffer_size;

940

989

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

941

&decrypted_buffer);

990

&decrypted_buffer, mc);

942

991

if(decrypted_buffer_size >= 0){

943

992

944

993

written = 0;

992

1041

return retval;

993

1042

}

994

1043

1044

__attribute__((nonnull))

995

1045

static void resolve_callback(AvahiSServiceResolver *r,

996

1046

AvahiIfIndex interface,

997

1047

AvahiProtocol proto,

1005

1055

AVAHI_GCC_UNUSED AvahiStringList *txt,

1006

1056

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1007

1057

flags,

1008

AVAHI_GCC_UNUSED void* userdata){

1009

assert(r);

1058

void *mc){

1059

if(r == NULL){

1060

return;

1061

}

1010

1062

1011

1063

/* Called whenever a service has been resolved successfully or

1012

1064

timed out */

1021

1073

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

1022

1074

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

1023

1075

domain,

1024

avahi_strerror(avahi_server_errno(mc.server)));

1076

avahi_strerror(avahi_server_errno

1077

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

1025

1078

break;

1026

1079

1027

1080

case AVAHI_RESOLVER_FOUND:

1033

1086

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

1034

1087

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

1035

1088

}

1036

int ret = start_mandos_communication(ip, port, interface,

1037

avahi_proto_to_af(proto));

1089

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

1090

interface,

1091

avahi_proto_to_af(proto),

1092

mc);

1038

1093

if(ret == 0){

1039

avahi_simple_poll_quit(mc.simple_poll);

1094

avahi_simple_poll_quit(simple_poll);

1040

1095

} else {

1041

if(not add_server(ip, port, interface,

1042

avahi_proto_to_af(proto))){

1096

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

1097

avahi_proto_to_af(proto),

1098

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

1043

1099

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

1044

1100

" list\n", name);

1045

1101

}

1058

1114

const char *domain,

1059

1115

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1116

flags,

1061

AVAHI_GCC_UNUSED void* userdata){

1062

assert(b);

1117

void *mc){

1118

if(b == NULL){

1119

return;

1120

}

1063

1121

1064

1122

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

1065

1123

is removed from the LAN */

1073

1131

case AVAHI_BROWSER_FAILURE:

1074

1132

1075

1133

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

1076

avahi_strerror(avahi_server_errno(mc.server)));

1077

avahi_simple_poll_quit(mc.simple_poll);

1134

avahi_strerror(avahi_server_errno

1135

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

1136

avahi_simple_poll_quit(simple_poll);

1078

1137

return;

1079

1138

1080

1139

case AVAHI_BROWSER_NEW:

1083

1142

the callback function is called the Avahi server will free the

1084

1143

resolver for us. */

1085

1144

1086

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

1087

name, type, domain, protocol, 0,

1088

resolve_callback, NULL) == NULL)

1145

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

1146

interface, protocol, name, type,

1147

domain, protocol, 0,

1148

resolve_callback, mc) == NULL)

1089

1149

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

1090

1150

" %s\n", name,

1091

avahi_strerror(avahi_server_errno(mc.server)));

1151

avahi_strerror(avahi_server_errno

1152

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

1092

1153

break;

1093

1154

1094

1155

case AVAHI_BROWSER_REMOVE:

1113

1174

signal_received = sig;

1114

1175

int old_errno = errno;

1115

1176

/* set main loop to exit */

1116

if(mc.simple_poll != NULL){

1117

avahi_simple_poll_quit(mc.simple_poll);

1177

if(simple_poll != NULL){

1178

avahi_simple_poll_quit(simple_poll);

1118

1179

}

1119

1180

errno = old_errno;

1120

1181

}

1121

1182

1183

__attribute__((nonnull, warn_unused_result))

1122

1184

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

1123

1185

int ret;

1186

error_t ret_errno;

1124

1187

1125

1188

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

1126

1189

if(s < 0){

1190

ret_errno = errno;

1127

1191

perror_plus("socket");

1192

errno = ret_errno;

1128

1193

return false;

1129

1194

}

1130

1195

strcpy(ifr->ifr_name, ifname);

1131

1196

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1132

1197

if(ret == -1){

1133

1198

if(debug){

1199

ret_errno = errno;

1134

1200

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1135

1202

}

1136

1203

return false;

1137

1204

}

1138

1205

return true;

1139

1206

}

1140

1207

1208

__attribute__((nonnull, warn_unused_result))

1141

1209

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

1142

1210

1143

1211

/* Reject the loopback device */

1185

1253

* corresponds to an acceptable network device.

1186

1254

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

1187

1255

*/

1256

__attribute__((nonnull, warn_unused_result))

1188

1257

int good_interface(const struct dirent *if_entry){

1189

1258

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

1190

1259

return 0;

1206

1275

}

1207

1276

1208

1277

/*

1209

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

1210

* corresponds to an acceptable network device which is up.

1211

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

1212

*/

1213

int up_interface(const struct dirent *if_entry){

1214

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

1215

return 0;

1216

}

1217

1218

struct ifreq ifr;

1219

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

1220

if(debug){

1221

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

1222

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

1223

}

1224

return 0;

1225

}

1226

1227

/* Reject down interfaces */

1228

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

1229

if(debug){

1230

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

1231

if_entry->d_name);

1232

}

1233

return 0;

1234

}

1235

1236

/* Reject non-running interfaces */

1237

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

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

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

1246

return 0;

1247

}

1248

return 1;

1249

}

1250

1278

* This function determines if a network interface is up.

1279

*/

1280

__attribute__((nonnull, warn_unused_result))

1281

bool interface_is_up(const char *interface){

1282

struct ifreq ifr;

1283

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

1284

if(debug){

1285

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

1286

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

1287

}

1288

return false;

1289

}

1290

1291

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

1292

}

1293

1294

/*

1295

* This function determines if a network interface is running

1296

*/

1297

__attribute__((nonnull, warn_unused_result))

1298

bool interface_is_running(const char *interface){

1299

struct ifreq ifr;

1300

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

1301

if(debug){

1302

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

1303

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

1304

}

1305

return false;

1306

}

1307

1308

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

1309

}

1310

1311

__attribute__((nonnull, pure, warn_unused_result))

1251

1312

int notdotentries(const struct dirent *direntry){

1252

1313

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

1253

1314

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

1260

1321

}

1261

1322

1262

1323

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

1324

__attribute__((nonnull, warn_unused_result))

1263

1325

int runnable_hook(const struct dirent *direntry){

1264

1326

int ret;

1265

1327

size_t sret;

1320

1382

return 1;

1321

1383

}

1322

1384

1323

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1385

__attribute__((nonnull, warn_unused_result))

1386

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1387

mandos_context *mc){

1324

1388

int ret;

1325

1389

struct timespec now;

1326

1390

struct timespec waited_time;

1327

1391

intmax_t block_time;

1328

1392

1329

1393

while(true){

1330

if(mc.current_server == NULL){

1331

if (debug){

1394

if(mc->current_server == NULL){

1395

if(debug){

1332

1396

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

1333

1397

" No timeout!\n");

1334

1398

}

1335

1399

ret = avahi_simple_poll_iterate(s, -1);

1336

1400

} else {

1337

if (debug){

1401

if(debug){

1338

1402

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

1339

1403

" it, or wait\n");

1340

1404

}

1347

1411

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

1348

1412

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

1349

1413

waited_time.tv_sec = (now.tv_sec

1350

- mc.current_server->last_seen.tv_sec);

1414

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

1351

1415

waited_time.tv_nsec = (now.tv_nsec

1352

- mc.current_server->last_seen.tv_nsec);

1416

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

1353

1417

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

1354

1418

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

1355

1419

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

1357

1421

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

1358

1422

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

1359

1423

1360

if (debug){

1424

if(debug){

1361

1425

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

1362

1426

block_time);

1363

1427

}

1364

1428

1365

1429

if(block_time <= 0){

1366

ret = start_mandos_communication(mc.current_server->ip,

1367

mc.current_server->port,

1368

mc.current_server->if_index,

1369

mc.current_server->af);

1430

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

1431

mc->current_server->port,

1432

mc->current_server->if_index,

1433

mc->current_server->af, mc);

1370

1434

if(ret == 0){

1371

avahi_simple_poll_quit(mc.simple_poll);

1435

avahi_simple_poll_quit(s);

1372

1436

return 0;

1373

1437

}

1374

1438

ret = clock_gettime(CLOCK_MONOTONIC,

1375

&mc.current_server->last_seen);

1439

&mc->current_server->last_seen);

1376

1440

if(ret == -1){

1377

1441

perror_plus("clock_gettime");

1378

1442

return -1;

1379

1443

}

1380

mc.current_server = mc.current_server->next;

1444

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

1381

1445

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

1382

1446

servers, but don't block */

1383

1447

}

1385

1449

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

1386

1450

}

1387

1451

if(ret != 0){

1388

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

1452

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

1389

1453

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

1390

1454

}

1391

1455

}

1393

1457

}

1394

1458

1395

1459

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

1396

int raise_privileges(void){

1397

int old_errno = errno;

1398

int ret_errno = 0;

1399

errno = 0;

1460

__attribute__((warn_unused_result))

1461

error_t raise_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1400

1464

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

1465

ret_errno = errno;

1401

1466

perror_plus("seteuid");

1402

1467

}

1403

ret_errno = errno;

1404

1468

errno = old_errno;

1405

1469

return ret_errno;

1406

1470

}

1407

1471

1408

1472

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

1409

int raise_privileges_permanently(void){

1410

int old_errno = errno;

1411

int ret_errno = raise_privileges();

1473

__attribute__((warn_unused_result))

1474

error_t raise_privileges_permanently(void){

1475

error_t old_errno = errno;

1476

error_t ret_errno = raise_privileges();

1412

1477

if(ret_errno != 0){

1413

1478

errno = old_errno;

1414

1479

return ret_errno;

1415

1480

}

1416

errno = 0;

1417

1481

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

1482

ret_errno = errno;

1418

1483

perror_plus("seteuid");

1419

1484

}

1420

ret_errno = errno;

1421

1485

errno = old_errno;

1422

1486

return ret_errno;

1423

1487

}

1424

1488

1425

1489

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

1426

int lower_privileges(void){

1427

int old_errno = errno;

1428

int ret_errno = 0;

1429

errno = 0;

1490

__attribute__((warn_unused_result))

1491

error_t lower_privileges(void){

1492

error_t old_errno = errno;

1493

error_t ret_errno = 0;

1430

1494

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

1495

ret_errno = errno;

1431

1496

perror_plus("seteuid");

1432

1497

}

1433

ret_errno = errno;

1434

errno = old_errno;

1435

return ret_errno;

1436

}

1437

1438

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

1498

errno = old_errno;

1499

return ret_errno;

1500

}

1501

1502

/* Lower privileges permanently */

1503

__attribute__((warn_unused_result))

1504

error_t lower_privileges_permanently(void){

1505

error_t old_errno = errno;

1506

error_t ret_errno = 0;

1507

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

1508

ret_errno = errno;

1509

perror_plus("setuid");

1510

}

1511

errno = old_errno;

1512

return ret_errno;

1513

}

1514

1515

__attribute__((nonnull))

1516

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

1439

1517

const float delay){

1440

1518

struct dirent **direntries;

1441

struct dirent *direntry;

1442

int ret;

1443

1519

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

1444

1520

alphasort);

1445

1521

if(numhooks == -1){

1446

perror_plus("scandir");

1522

if(errno == ENOENT){

1523

if(debug){

1524

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

1525

" found\n", hookdir);

1526

}

1527

} else {

1528

perror_plus("scandir");

1529

}

1447

1530

} else {

1531

struct dirent *direntry;

1532

int ret;

1448

1533

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

1449

1534

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

1450

1535

direntry = direntries[i];

1462

1547

if(hook_pid == 0){

1463

1548

/* Child */

1464

1549

/* Raise privileges */

1465

raise_privileges_permanently();

1550

if(raise_privileges_permanently() != 0){

1551

perror_plus("Failed to raise privileges");

1552

_exit(EX_NOPERM);

1553

}

1466

1554

/* Set group */

1467

1555

errno = 0;

1468

1556

ret = setgid(0);

1469

1557

if(ret == -1){

1470

1558

perror_plus("setgid");

1559

_exit(EX_NOPERM);

1471

1560

}

1472

1561

/* Reset supplementary groups */

1473

1562

errno = 0;

1474

1563

ret = setgroups(0, NULL);

1475

1564

if(ret == -1){

1476

1565

perror_plus("setgroups");

1477

}

1478

dup2(devnull, STDIN_FILENO);

1479

close(devnull);

1480

dup2(STDERR_FILENO, STDOUT_FILENO);

1566

_exit(EX_NOPERM);

1567

}

1568

ret = dup2(devnull, STDIN_FILENO);

1569

if(ret == -1){

1570

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

1571

_exit(EX_OSERR);

1572

}

1573

ret = close(devnull);

1574

if(ret == -1){

1575

perror_plus("close");

1576

_exit(EX_OSERR);

1577

}

1578

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1579

if(ret == -1){

1580

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

1581

_exit(EX_OSERR);

1582

}

1481

1583

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

1482

1584

if(ret == -1){

1483

1585

perror_plus("setenv");

1499

1601

_exit(EX_OSERR);

1500

1602

}

1501

1603

char *delaystring;

1502

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

1604

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

1503

1605

if(ret == -1){

1504

1606

perror_plus("asprintf");

1505

1607

_exit(EX_OSERR);

1558

1660

}

1559

1661

close(devnull);

1560

1662

}

1561

return true;

1562

1663

}

1563

1664

1564

int bring_up_interface(const char * const interface, const float delay){

1565

int sd = -1;

1665

__attribute__((nonnull, warn_unused_result))

1666

error_t bring_up_interface(const char *const interface,

1667

const float delay){

1668

error_t old_errno = errno;

1566

1669

int ret;

1567

1670

struct ifreq network;

1568

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

1671

unsigned int if_index = if_nametoindex(interface);

1569

1672

if(if_index == 0){

1570

1673

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

1571

return EX_UNAVAILABLE;

1674

errno = old_errno;

1675

return ENXIO;

1572

1676

}

1573

1677

1574

1678

if(quit_now){

1679

errno = old_errno;

1575

1680

return EINTR;

1576

1681

}

1577

1682

1578

/* Re-raise priviliges */

1579

raise_privileges();

1580

1581

#ifdef __linux__

1582

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1583

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

1584

ret = klogctl(8, NULL, 5);

1585

bool restore_loglevel = true;

1586

if(ret == -1){

1587

restore_loglevel = false;

1588

perror_plus("klogctl");

1589

}

1590

#endif /* __linux__ */

1591

1592

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1593

if(sd < 0){

1594

perror_plus("socket");

1595

#ifdef __linux__

1596

if(restore_loglevel){

1597

ret = klogctl(7, NULL, 0);

1598

if(ret == -1){

1599

perror_plus("klogctl");

1600

}

1601

}

1602

#endif /* __linux__ */

1603

/* Lower privileges */

1604

lower_privileges();

1605

return EX_OSERR;

1606

;

1607

}

1608

strcpy(network.ifr_name, interface);

1609

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

1610

if(ret == -1){

1611

perror_plus("ioctl SIOCGIFFLAGS");

1612

#ifdef __linux__

1613

if(restore_loglevel){

1614

ret = klogctl(7, NULL, 0);

1615

if(ret == -1){

1616

perror_plus("klogctl");

1617

}

1618

}

1619

#endif /* __linux__ */

1620

/* Lower privileges */

1621

lower_privileges();

1622

return EX_OSERR;

1623

}

1624

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

1625

network.ifr_flags |= IFF_UP;

1626

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

1683

if(not interface_is_up(interface)){

1684

error_t ret_errno = 0, ioctl_errno = 0;

1685

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

1686

ret_errno = errno;

1687

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

1688

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

1689

errno = old_errno;

1690

return ret_errno;

1691

}

1692

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

1693

1694

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

1695

if(sd == -1){

1696

ret_errno = errno;

1697

perror_plus("socket");

1698

errno = old_errno;

1699

return ret_errno;

1700

}

1701

1702

if(quit_now){

1703

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

1704

if(ret == -1){

1705

perror_plus("close");

1706

}

1707

errno = old_errno;

1708

return EINTR;

1709

}

1710

1711

if(debug){

1712

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

1713

interface);

1714

}

1715

1716

/* Raise privileges */

1717

ret_errno = raise_privileges();

1718

bool restore_loglevel = false;

1719

if(ret_errno != 0){

1720

perror_plus("Failed to raise privileges");

1721

}

1722

#ifdef __linux__

1723

int ret_linux;

1724

if(ret_errno == 0){

1725

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1726

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

1727

ret_linux = klogctl(8, NULL, 5);

1728

if(ret_linux == -1){

1729

perror_plus("klogctl");

1730

} else {

1731

restore_loglevel = true;

1732

}

1733

}

1734

#endif /* __linux__ */

1735

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

1736

ioctl_errno = errno;

1737

#ifdef __linux__

1738

if(restore_loglevel){

1739

ret_linux = klogctl(7, NULL, 0);

1740

if(ret_linux == -1){

1741

perror_plus("klogctl");

1742

}

1743

}

1744

#endif /* __linux__ */

1745

1746

/* If raise_privileges() succeeded above */

1747

if(ret_errno == 0){

1748

/* Lower privileges */

1749

ret_errno = lower_privileges();

1750

if(ret_errno != 0){

1751

errno = ret_errno;

1752

perror_plus("Failed to lower privileges");

1753

}

1754

}

1755

1756

/* Close the socket */

1757

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

1627

1758

if(ret == -1){

1759

perror_plus("close");

1760

}

1761

1762

if(ret_setflags == -1){

1763

errno = ioctl_errno;

1628

1764

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1629

#ifdef __linux__

1630

if(restore_loglevel){

1631

ret = klogctl(7, NULL, 0);

1632

if(ret == -1){

1633

perror_plus("klogctl");

1634

}

1635

}

1636

#endif /* __linux__ */

1637

/* Lower privileges */

1638

lower_privileges();

1639

return EX_OSERR;

1765

errno = old_errno;

1766

return ioctl_errno;

1640

1767

}

1768

} else if(debug){

1769

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

1770

interface);

1641

1771

}

1772

1642

1773

/* Sleep checking until interface is running.

1643

1774

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

1644

1775

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

1645

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

1646

if(ret == -1){

1647

perror_plus("ioctl SIOCGIFFLAGS");

1648

} else if(network.ifr_flags & IFF_RUNNING){

1776

if(interface_is_running(interface)){

1649

1777

break;

1650

1778

}

1651

1779

struct timespec sleeptime = { .tv_nsec = 250000000 };

1654

1782

perror_plus("nanosleep");

1655

1783

}

1656

1784

}

1657

/* Close the socket */

1658

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

1659

if(ret == -1){

1660

perror_plus("close");

1785

1786

errno = old_errno;

1787

return 0;

1788

}

1789

1790

__attribute__((nonnull, warn_unused_result))

1791

error_t take_down_interface(const char *const interface){

1792

error_t old_errno = errno;

1793

struct ifreq network;

1794

unsigned int if_index = if_nametoindex(interface);

1795

if(if_index == 0){

1796

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

1797

errno = old_errno;

1798

return ENXIO;

1661

1799

}

1662

#ifdef __linux__

1663

if(restore_loglevel){

1664

/* Restores kernel loglevel to default */

1665

ret = klogctl(7, NULL, 0);

1800

if(interface_is_up(interface)){

1801

error_t ret_errno = 0, ioctl_errno = 0;

1802

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

1803

ret_errno = errno;

1804

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

1805

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

1806

errno = old_errno;

1807

return ret_errno;

1808

}

1809

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

1810

1811

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

1812

if(sd == -1){

1813

ret_errno = errno;

1814

perror_plus("socket");

1815

errno = old_errno;

1816

return ret_errno;

1817

}

1818

1819

if(debug){

1820

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

1821

interface);

1822

}

1823

1824

/* Raise privileges */

1825

ret_errno = raise_privileges();

1826

if(ret_errno != 0){

1827

perror_plus("Failed to raise privileges");

1828

}

1829

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

1830

ioctl_errno = errno;

1831

1832

/* If raise_privileges() succeeded above */

1833

if(ret_errno == 0){

1834

/* Lower privileges */

1835

ret_errno = lower_privileges();

1836

if(ret_errno != 0){

1837

errno = ret_errno;

1838

perror_plus("Failed to lower privileges");

1839

}

1840

}

1841

1842

/* Close the socket */

1843

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

1666

1844

if(ret == -1){

1667

perror_plus("klogctl");

1668

}

1845

perror_plus("close");

1846

}

1847

1848

if(ret_setflags == -1){

1849

errno = ioctl_errno;

1850

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1851

errno = old_errno;

1852

return ioctl_errno;

1853

}

1854

} else if(debug){

1855

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

1856

interface);

1669

1857

}

1670

#endif /* __linux__ */

1671

/* Lower privileges */

1672

lower_privileges();

1673

return errno;

1858

1859

errno = old_errno;

1860

return 0;

1674

1861

}

1675

1862

1676

1863

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

1864

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

1865

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

1866

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

1867

.interfaces = NULL, .interfaces_size = 0 };

1677

1868

AvahiSServiceBrowser *sb = NULL;

1678

int error;

1869

error_t ret_errno;

1679

1870

int ret;

1680

1871

intmax_t tmpmax;

1681

1872

char *tmp;

1682

1873

int exitcode = EXIT_SUCCESS;

1683

const char *interface = "";

1684

struct ifreq network;

1685

int sd = -1;

1686

bool take_down_interface = false;

1687

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

1688

bool tempdir_created = false;

1874

char *interfaces_to_take_down = NULL;

1875

size_t interfaces_to_take_down_size = 0;

1876

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

1877

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

1878

char *tempdir = NULL;

1689

1879

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1690

1880

const char *seckey = PATHDIR "/" SECKEY;

1691

1881

const char *pubkey = PATHDIR "/" PUBKEY;

1882

char *interfaces_hooks = NULL;

1692

1883

1693

1884

bool gnutls_initialized = false;

1694

1885

bool gpgme_initialized = false;

1785

1976

connect_to = arg;

1786

1977

break;

1787

1978

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

1788

interface = arg;

1979

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

1980

arg, (int)',');

1981

if(ret_errno != 0){

1982

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

1983

}

1789

1984

break;

1790

1985

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

1791

1986

seckey = arg;

1868

2063

/* Work around Debian bug #633582:

1869

2064

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

1870

2065

1871

/* Re-raise priviliges */

1872

if(raise_privileges() == 0){

2066

/* Re-raise privileges */

2067

ret_errno = raise_privileges();

2068

if(ret_errno != 0){

2069

errno = ret_errno;

2070

perror_plus("Failed to raise privileges");

2071

} else {

1873

2072

struct stat st;

1874

2073

1875

2074

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

1915

2114

}

1916

2115

1917

2116

/* Lower privileges */

1918

errno = 0;

1919

ret = seteuid(uid);

1920

if(ret == -1){

1921

perror_plus("seteuid");

2117

ret_errno = lower_privileges();

2118

if(ret_errno != 0){

2119

errno = ret_errno;

2120

perror_plus("Failed to lower privileges");

2121

}

2122

}

2123

}

2124

2125

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

2126

{

2127

char *interface = NULL;

2128

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

2129

interface))){

2130

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

2131

and if_nametoindex(interface) == 0){

2132

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

2133

fprintf_plus(stderr, "Not using nonexisting interface"

2134

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

2135

}

2136

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

2137

interface = NULL;

1922

2138

}

1923

2139

}

1924

2140

}

1925

2141

1926

2142

/* Run network hooks */

1927

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

1928

goto end;

2143

{

2144

if(mc.interfaces != NULL){

2145

interfaces_hooks = malloc(mc.interfaces_size);

2146

if(interfaces_hooks == NULL){

2147

perror_plus("malloc");

2148

goto end;

2149

}

2150

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

2151

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

2152

}

2153

run_network_hooks("start", interfaces_hooks != NULL ?

2154

interfaces_hooks : "", delay);

1929

2155

}

1930

2156

1931

2157

if(not debug){

1932

2158

avahi_set_log_function(empty_log);

1933

2159

}

1934

2160

1935

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

1936

struct dirent **direntries;

1937

/* First look for interfaces that are up */

1938

ret = scandir(sys_class_net, &direntries, up_interface,

1939

alphasort);

1940

if(ret == 0){

1941

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

1942

free(direntries);

1943

ret = scandir(sys_class_net, &direntries, good_interface,

1944

alphasort);

1945

}

1946

if(ret >= 1){

1947

/* Pick the first interface returned */

1948

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

1949

if(debug){

1950

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

1951

}

1952

if(interface == NULL){

1953

perror_plus("malloc");

1954

free(direntries);

1955

exitcode = EXIT_FAILURE;

1956

goto end;

1957

}

1958

free(direntries);

1959

} else {

1960

free(direntries);

1961

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

1962

exitcode = EXIT_FAILURE;

1963

goto end;

1964

}

1965

}

1966

1967

2161

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

1968

2162

from the signal handler */

1969

2163

/* Initialize the pseudo-RNG for Avahi */

1970

2164

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

1971

mc.simple_poll = avahi_simple_poll_new();

1972

if(mc.simple_poll == NULL){

2165

simple_poll = avahi_simple_poll_new();

2166

if(simple_poll == NULL){

1973

2167

fprintf_plus(stderr,

1974

2168

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

1975

2169

exitcode = EX_UNAVAILABLE;

2039

2233

}

2040

2234

}

2041

2235

2042

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

2043

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

2044

ret = bring_up_interface(interface, delay);

2045

if(ret){

2046

errno = ret;

2047

perror_plus("Failed to bring up interface");

2048

}

2236

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

2237

if(mc.interfaces == NULL){

2238

struct dirent **direntries;

2239

/* Look for any good interfaces */

2240

ret = scandir(sys_class_net, &direntries, good_interface,

2241

alphasort);

2242

if(ret >= 1){

2243

/* Add all found interfaces to interfaces list */

2244

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

2245

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

2246

direntries[i]->d_name);

2247

if(ret_errno != 0){

2248

errno = ret_errno;

2249

perror_plus("argz_add");

2250

continue;

2251

}

2252

if(debug){

2253

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

2254

direntries[i]->d_name);

2255

}

2256

}

2257

free(direntries);

2258

} else {

2259

free(direntries);

2260

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

2261

exitcode = EXIT_FAILURE;

2262

goto end;

2263

}

2264

}

2265

2266

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

2267

{

2268

char *interface = NULL;

2269

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

2270

interface))){

2271

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

2272

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

2273

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

2274

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

2275

interface);

2276

interface = NULL;

2277

while((interface = argz_next(mc.interfaces,

2278

mc.interfaces_size, interface))){

2279

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

2280

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

2281

interface);

2282

interface = NULL;

2283

}

2284

}

2285

break;

2286

}

2287

bool interface_was_up = interface_is_up(interface);

2288

errno = bring_up_interface(interface, delay);

2289

if(not interface_was_up){

2290

if(errno != 0){

2291

perror_plus("Failed to bring up interface");

2292

} else {

2293

errno = argz_add(&interfaces_to_take_down,

2294

&interfaces_to_take_down_size,

2295

interface);

2296

if(errno != 0){

2297

perror_plus("argz_add");

2298

}

2299

}

2300

}

2301

}

2302

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

2303

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

2304

}

2305

}

2306

2307

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

2308

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

2309

if(debug){

2310

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

2311

mc.interfaces);

2312

}

2313

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

2049

2314

}

2050

2315

2051

2316

if(quit_now){

2052

2317

goto end;

2053

2318

}

2054

2319

2055

ret = init_gnutls_global(pubkey, seckey);

2320

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

2056

2321

if(ret == -1){

2057

2322

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

2058

2323

exitcode = EX_UNAVAILABLE;

2065

2330

goto end;

2066

2331

}

2067

2332

2068

if(mkdtemp(tempdir) == NULL){

2333

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

2334

tempdir = mkdtemp(run_tempdir);

2335

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

2336

if(debug){

2337

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

2338

run_tempdir, old_tempdir);

2339

}

2340

tempdir = mkdtemp(old_tempdir);

2341

}

2342

if(tempdir == NULL){

2069

2343

perror_plus("mkdtemp");

2070

2344

goto end;

2071

2345

}

2072

tempdir_created = true;

2073

2346

2074

2347

if(quit_now){

2075

2348

goto end;

2076

2349

}

2077

2350

2078

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

2351

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

2079

2352

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

2080

2353

exitcode = EX_UNAVAILABLE;

2081

2354

goto end;

2102

2375

goto end;

2103

2376

}

2104

2377

2105

uint16_t port;

2378

in_port_t port;

2106

2379

errno = 0;

2107

2380

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

2108

2381

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

2109

or tmpmax != (uint16_t)tmpmax){

2382

or tmpmax != (in_port_t)tmpmax){

2110

2383

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

2111

2384

exitcode = EX_USAGE;

2112

2385

goto end;

2113

2386

}

2114

2387

2115

2388

if(quit_now){

2116

2389

goto end;

2117

2390

}

2118

2391

2119

port = (uint16_t)tmpmax;

2392

port = (in_port_t)tmpmax;

2120

2393

*address = '\0';

2121

2394

/* Colon in address indicates IPv6 */

2122

2395

int af;

2138

2411

}

2139

2412

2140

2413

while(not quit_now){

2141

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

2414

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

2415

&mc);

2142

2416

if(quit_now or ret == 0){

2143

2417

break;

2144

2418

}

2146

2420

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

2147

2421

(int)retry_interval);

2148

2422

}

2149

sleep((int)retry_interval);

2423

sleep((unsigned int)retry_interval);

2150

2424

}

2151

2425

2152

if (not quit_now){

2426

if(not quit_now){

2153

2427

exitcode = EXIT_SUCCESS;

2154

2428

}

2155

2429

2170

2444

config.publish_domain = 0;

2171

2445

2172

2446

/* Allocate a new server */

2173

mc.server = avahi_server_new(avahi_simple_poll_get

2174

(mc.simple_poll), &config, NULL,

2175

NULL, &error);

2447

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2448

&config, NULL, NULL, &ret_errno);

2176

2449

2177

2450

/* Free the Avahi configuration data */

2178

2451

avahi_server_config_free(&config);

2181

2454

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

2182

2455

if(mc.server == NULL){

2183

2456

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

2184

avahi_strerror(error));

2457

avahi_strerror(ret_errno));

2185

2458

exitcode = EX_UNAVAILABLE;

2186

2459

goto end;

2187

2460

}

2193

2466

/* Create the Avahi service browser */

2194

2467

sb = avahi_s_service_browser_new(mc.server, if_index,

2195

2468

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2196

NULL, 0, browse_callback, NULL);

2469

NULL, 0, browse_callback,

2470

(void *)&mc);

2197

2471

if(sb == NULL){

2198

2472

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

2199

2473

avahi_strerror(avahi_server_errno(mc.server)));

2211

2485

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

2212

2486

}

2213

2487

2214

ret = avahi_loop_with_timeout(mc.simple_poll,

2215

(int)(retry_interval * 1000));

2488

ret = avahi_loop_with_timeout(simple_poll,

2489

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

2216

2490

if(debug){

2217

2491

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

2218

2492

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

2225

2499

}

2226

2500

2227

2501

/* Cleanup things */

2502

free(mc.interfaces);

2503

2228

2504

if(sb != NULL)

2229

2505

avahi_s_service_browser_free(sb);

2230

2506

2231

2507

if(mc.server != NULL)

2232

2508

avahi_server_free(mc.server);

2233

2509

2234

if(mc.simple_poll != NULL)

2235

avahi_simple_poll_free(mc.simple_poll);

2510

if(simple_poll != NULL)

2511

avahi_simple_poll_free(simple_poll);

2236

2512

2237

2513

if(gnutls_initialized){

2238

2514

gnutls_certificate_free_credentials(mc.cred);

2255

2531

}

2256

2532

}

2257

2533

2258

/* Run network hooks */

2259

run_network_hooks("stop", interface, delay);

2260

2261

/* Re-raise priviliges */

2534

/* Re-raise privileges */

2262

2535

{

2263

raise_privileges();

2264

2265

/* Take down the network interface */

2266

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

2267

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

2268

if(ret == -1){

2269

perror_plus("ioctl SIOCGIFFLAGS");

2270

} else if(network.ifr_flags & IFF_UP){

2271

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

2272

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

2273

if(ret == -1){

2274

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2275

}

2276

}

2277

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

2278

if(ret == -1){

2279

perror_plus("close");

2280

}

2281

}

2282

}

2283

/* Lower privileges permanently */

2284

errno = 0;

2285

ret = setuid(uid);

2286

if(ret == -1){

2287

perror_plus("setuid");

2288

}

2536

ret_errno = raise_privileges();

2537

if(ret_errno != 0){

2538

perror_plus("Failed to raise privileges");

2539

} else {

2540

2541

/* Run network hooks */

2542

run_network_hooks("stop", interfaces_hooks != NULL ?

2543

interfaces_hooks : "", delay);

2544

2545

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

2546

{

2547

char *interface = NULL;

2548

while((interface=argz_next(interfaces_to_take_down,

2549

interfaces_to_take_down_size,

2550

interface))){

2551

ret_errno = take_down_interface(interface);

2552

if(ret_errno != 0){

2553

errno = ret_errno;

2554

perror_plus("Failed to take down interface");

2555

}

2556

}

2557

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

2558

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

2559

" down\n");

2560

}

2561

}

2562

}

2563

ret_errno = lower_privileges_permanently();

2564

if(ret_errno != 0){

2565

perror_plus("Failed to lower privileges permanently");

2566

}

2567

}

2568

2569

free(interfaces_to_take_down);

2570

free(interfaces_hooks);

2289

2571

2290

2572

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

2291

if(tempdir_created){

2573

if(tempdir != NULL){

2292

2574

struct dirent **direntries = NULL;

2293

2575

struct dirent *direntry = NULL;

2294

2576

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

2295

2577

alphasort);

2296

if (numentries > 0){

2578

if(numentries > 0){

2297

2579

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

2298

2580

direntry = direntries[i];

2299

2581

char *fullname = NULL;

2314

2596

2315

2597

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

2316

2598

free(direntries);

2317

if (numentries == -1){

2599

if(numentries == -1){

2318

2600

perror_plus("scandir");

2319

2601

}

2320

2602

ret = rmdir(tempdir);