/mandos/trunk : revision 533

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* "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

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

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stdout, ferror(), remove() */

44

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

44

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

45

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

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

47

strtof(), abort() */

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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getnameinfo() */

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inet_pton(), connect() */

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59

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

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

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61

*/

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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() */

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

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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() */

95

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

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EAI_SYSTEM, gai_strerror() */

97

91

98

92

#ifdef __linux__

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93

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

141

135

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

142

136

char *connect_to = NULL;

143

137

const char *hookdir = HOOKDIR;

144

uid_t uid = 65534;

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gid_t gid = 65534;

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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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in_port_t port;

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uint16_t port;

151

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AvahiIfIndex if_index;

152

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int af;

153

145

struct timespec last_seen;

157

149

158

150

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

159

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typedef struct {

152

AvahiSimplePoll *simple_poll;

160

153

AvahiServer *server;

161

154

gnutls_certificate_credentials_t cred;

162

155

unsigned int dh_bits;

164

157

const char *priority;

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158

gpgme_ctx_t ctx;

166

159

server *current_server;

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char *interfaces;

168

size_t interfaces_size;

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160

} mandos_context;

170

161

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/* global so signal handler can reach it*/

172

AvahiSimplePoll *simple_poll;

162

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

173

167

174

168

sig_atomic_t quit_now = 0;

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int signal_received = 0;

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170

177

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/* Function to use when printing errors */

178

172

void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

185

177

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

178

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

187

179

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

188

180

va_list ap;

189

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va_start (ap, format);

190

182

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

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184

program_invocation_short_name));

193

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

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

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}

195

187

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/*

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

199

191

* "buffer_length" is how much is already used.

200

192

*/

201

__attribute__((nonnull, warn_unused_result))

202

193

size_t incbuffer(char **buffer, size_t buffer_length,

203

194

size_t buffer_capacity){

204

195

if(buffer_length + BUFFER_SIZE > buffer_capacity){

205

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

206

if(new_buf == NULL){

207

int old_errno = errno;

208

free(*buffer);

209

errno = old_errno;

210

*buffer = NULL;

196

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

197

if(buffer == NULL){

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return 0;

212

199

}

213

*buffer = new_buf;

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200

buffer_capacity += BUFFER_SIZE;

215

201

}

216

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return buffer_capacity;

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203

}

218

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

220

__attribute__((nonnull, warn_unused_result))

221

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

207

int af){

223

208

int ret;

224

209

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

225

210

if(new_server == NULL){

234

219

perror_plus("strdup");

235

220

return false;

236

221

}

237

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

240

return false;

241

}

242

222

/* Special case of first server */

243

if(*current_server == NULL){

223

if (mc.current_server == NULL){

244

224

new_server->next = new_server;

245

225

new_server->prev = new_server;

246

*current_server = new_server;

226

mc.current_server = new_server;

227

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

247

228

} else {

248

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

249

new_server->next = *current_server;

250

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

229

new_server->next = mc.current_server;

230

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

251

231

new_server->prev->next = new_server;

252

(*current_server)->prev = new_server;

232

mc.current_server->prev = new_server;

233

}

234

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

235

if(ret == -1){

236

perror_plus("clock_gettime");

237

return false;

253

238

}

254

239

return true;

255

240

}

257

242

/*

258

243

* Initialize GPGME.

259

244

*/

260

__attribute__((nonnull, warn_unused_result))

261

245

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

262

const char *tempdir, mandos_context *mc){

246

const char *tempdir){

263

247

gpgme_error_t rc;

264

248

gpgme_engine_info_t engine_info;

265

249

250

266

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/*

267

252

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

268

253

*/

284

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return false;

285

270

}

286

271

287

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

272

rc = gpgme_op_import(mc.ctx, pgp_data);

288

273

if(rc != GPG_ERR_NO_ERROR){

289

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

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gpgme_strsource(rc), gpgme_strerror(rc));

334

319

}

335

320

336

321

/* Create new GPGME "context" */

337

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

322

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

338

323

if(rc != GPG_ERR_NO_ERROR){

339

324

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

340

325

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

353

338

* Decrypt OpenPGP data.

354

339

* Returns -1 on error

355

340

*/

356

__attribute__((nonnull, warn_unused_result))

357

341

static ssize_t pgp_packet_decrypt(const char *cryptotext,

358

342

size_t crypto_size,

359

char **plaintext,

360

mandos_context *mc){

343

char **plaintext){

361

344

gpgme_data_t dh_crypto, dh_plain;

362

345

gpgme_error_t rc;

363

346

ssize_t ret;

389

372

390

373

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

391

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data buffer */

392

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

375

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

393

376

if(rc != GPG_ERR_NO_ERROR){

394

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

395

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gpgme_strsource(rc), gpgme_strerror(rc));

396

379

plaintext_length = -1;

397

380

if(debug){

398

381

gpgme_decrypt_result_t result;

399

result = gpgme_op_decrypt_result(mc->ctx);

382

result = gpgme_op_decrypt_result(mc.ctx);

400

383

if(result == NULL){

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

402

385

} else {

479

462

return plaintext_length;

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463

}

481

464

482

__attribute__((warn_unused_result))

483

static const char *safer_gnutls_strerror(int value){

484

const char *ret = gnutls_strerror(value);

465

static const char * safer_gnutls_strerror(int value){

466

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

467

-Wunreachable-code */

485

468

if(ret == NULL)

486

469

ret = "(unknown)";

487

470

return ret;

488

471

}

489

472

490

473

/* GnuTLS log function callback */

491

__attribute__((nonnull))

492

474

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

493

475

const char* string){

494

476

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

495

477

}

496

478

497

__attribute__((nonnull, warn_unused_result))

498

479

static int init_gnutls_global(const char *pubkeyfilename,

499

const char *seckeyfilename,

500

mandos_context *mc){

480

const char *seckeyfilename){

501

481

int ret;

502

482

503

483

if(debug){

520

500

}

521

501

522

502

/* OpenPGP credentials */

523

ret = gnutls_certificate_allocate_credentials(&mc->cred);

503

ret = gnutls_certificate_allocate_credentials(&mc.cred);

524

504

if(ret != GNUTLS_E_SUCCESS){

525

505

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

526

506

safer_gnutls_strerror(ret));

536

516

}

537

517

538

518

ret = gnutls_certificate_set_openpgp_key_file

539

(mc->cred, pubkeyfilename, seckeyfilename,

519

(mc.cred, pubkeyfilename, seckeyfilename,

540

520

GNUTLS_OPENPGP_FMT_BASE64);

541

521

if(ret != GNUTLS_E_SUCCESS){

542

522

fprintf_plus(stderr,

548

528

}

549

529

550

530

/* GnuTLS server initialization */

551

ret = gnutls_dh_params_init(&mc->dh_params);

531

ret = gnutls_dh_params_init(&mc.dh_params);

552

532

if(ret != GNUTLS_E_SUCCESS){

553

533

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

554

534

" initialization: %s\n",

555

535

safer_gnutls_strerror(ret));

556

536

goto globalfail;

557

537

}

558

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

538

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

559

539

if(ret != GNUTLS_E_SUCCESS){

560

540

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

561

541

safer_gnutls_strerror(ret));

562

542

goto globalfail;

563

543

}

564

544

565

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

545

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

566

546

567

547

return 0;

568

548

569

549

globalfail:

570

550

571

gnutls_certificate_free_credentials(mc->cred);

551

gnutls_certificate_free_credentials(mc.cred);

572

552

gnutls_global_deinit();

573

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_dh_params_deinit(mc.dh_params);

574

554

return -1;

575

555

}

576

556

577

__attribute__((nonnull, warn_unused_result))

578

static int init_gnutls_session(gnutls_session_t *session,

579

mandos_context *mc){

557

static int init_gnutls_session(gnutls_session_t *session){

580

558

int ret;

581

559

/* GnuTLS session creation */

582

560

do {

594

572

{

595

573

const char *err;

596

574

do {

597

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

575

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

598

576

if(quit_now){

599

577

gnutls_deinit(*session);

600

578

return -1;

611

589

612

590

do {

613

591

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

614

mc->cred);

592

mc.cred);

615

593

if(quit_now){

616

594

gnutls_deinit(*session);

617

595

return -1;

627

605

/* ignore client certificate if any. */

628

606

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

629

607

630

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

608

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

631

609

632

610

return 0;

633

611

}

637

615

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

638

616

639

617

/* Called when a Mandos server is found */

640

__attribute__((nonnull, warn_unused_result))

641

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

618

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

642

619

AvahiIfIndex if_index,

643

int af, mandos_context *mc){

620

int af){

644

621

int ret, tcp_sd = -1;

645

622

ssize_t sret;

646

struct sockaddr_storage to;

623

union {

624

struct sockaddr_in in;

625

struct sockaddr_in6 in6;

626

} to;

647

627

char *buffer = NULL;

648

628

char *decrypted_buffer = NULL;

649

629

size_t buffer_length = 0;

673

653

return -1;

674

654

}

675

655

676

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

677

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

678

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

679

bool match = false;

680

{

681

char *interface = NULL;

682

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

683

interface))){

684

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

685

match = true;

686

break;

687

}

688

}

689

}

690

if(not match){

691

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

692

connect to the server */

693

if(debug){

694

char interface[IF_NAMESIZE];

695

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

696

perror_plus("if_indextoname");

697

} else {

698

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

699

" \"%s\"\n",

700

if_indextoname((unsigned int)if_index,

701

interface));

702

}

703

}

704

return -1;

705

}

706

}

707

708

ret = init_gnutls_session(&session, mc);

656

ret = init_gnutls_session(&session);

709

657

if(ret != 0){

710

658

return -1;

711

659

}

712

660

713

661

if(debug){

714

662

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

715

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

663

PRIu16 "\n", ip, port);

716

664

}

717

665

718

666

tcp_sd = socket(pf, SOCK_STREAM, 0);

730

678

731

679

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

732

680

if(af == AF_INET6){

733

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

734

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

681

to.in6.sin6_family = (sa_family_t)af;

682

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

735

683

} else { /* IPv4 */

736

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

737

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

684

to.in.sin_family = (sa_family_t)af;

685

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

738

686

}

739

687

if(ret < 0 ){

740

688

int e = errno;

749

697

goto mandos_end;

750

698

}

751

699

if(af == AF_INET6){

752

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

753

if(IN6_IS_ADDR_LINKLOCAL

754

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

700

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

701

-Wconversion and

702

-Wunreachable-code */

703

704

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

705

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

706

-Wunreachable-code*/

755

707

if(if_index == AVAHI_IF_UNSPEC){

756

708

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

757

709

" incomplete without a network interface\n");

759

711

goto mandos_end;

760

712

}

761

713

/* Set the network interface number as scope */

762

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

714

to.in6.sin6_scope_id = (uint32_t)if_index;

763

715

}

764

716

} else {

765

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

717

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

718

-Wconversion and

719

-Wunreachable-code */

766

720

}

767

721

768

722

if(quit_now){

776

730

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

777

731

perror_plus("if_indextoname");

778

732

} else {

779

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

780

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

733

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

734

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

781

735

}

782

736

} else {

783

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

784

ip, (uintmax_t)port);

737

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

738

ip, port);

785

739

}

786

740

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

787

741

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

742

const char *pcret;

788

743

if(af == AF_INET6){

789

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

790

sizeof(struct sockaddr_in6),

791

addrstr, sizeof(addrstr), NULL, 0,

792

NI_NUMERICHOST);

744

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

745

sizeof(addrstr));

793

746

} else {

794

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

795

sizeof(struct sockaddr_in),

796

addrstr, sizeof(addrstr), NULL, 0,

797

NI_NUMERICHOST);

747

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

748

sizeof(addrstr));

798

749

}

799

if(ret == EAI_SYSTEM){

800

perror_plus("getnameinfo");

801

} else if(ret != 0) {

802

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

803

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

804

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

750

if(pcret == NULL){

751

perror_plus("inet_ntop");

752

} else {

753

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

754

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

755

}

805

756

}

806

757

}

807

758

811

762

}

812

763

813

764

if(af == AF_INET6){

814

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

815

sizeof(struct sockaddr_in6));

765

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

816

766

} else {

817

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

818

sizeof(struct sockaddr_in));

767

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

819

768

}

820

769

if(ret < 0){

821

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

770

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

822

771

int e = errno;

823

772

perror_plus("connect");

824

773

errno = e;

870

819

goto mandos_end;

871

820

}

872

821

873

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

874

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

875

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

876

gnutls_transport_set_ptr(session,

877

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

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

823

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

878

824

879

825

if(quit_now){

880

826

errno = EINTR;

985

931

if(buffer_length > 0){

986

932

ssize_t decrypted_buffer_size;

987

933

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

988

&decrypted_buffer, mc);

934

&decrypted_buffer);

989

935

if(decrypted_buffer_size >= 0){

990

936

991

937

written = 0;

1039

985

return retval;

1040

986

}

1041

987

1042

__attribute__((nonnull))

1043

988

static void resolve_callback(AvahiSServiceResolver *r,

1044

989

AvahiIfIndex interface,

1045

990

AvahiProtocol proto,

1053

998

AVAHI_GCC_UNUSED AvahiStringList *txt,

1054

999

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1055

1000

flags,

1056

void *mc){

1057

if(r == NULL){

1058

return;

1059

}

1001

AVAHI_GCC_UNUSED void* userdata){

1002

assert(r);

1060

1003

1061

1004

/* Called whenever a service has been resolved successfully or

1062

1005

timed out */

1071

1014

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

1072

1015

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

1073

1016

domain,

1074

avahi_strerror(avahi_server_errno

1075

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

1017

avahi_strerror(avahi_server_errno(mc.server)));

1076

1018

break;

1077

1019

1078

1020

case AVAHI_RESOLVER_FOUND:

1084

1026

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

1085

1027

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

1086

1028

}

1087

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

1088

interface,

1089

avahi_proto_to_af(proto),

1090

mc);

1029

int ret = start_mandos_communication(ip, port, interface,

1030

avahi_proto_to_af(proto));

1091

1031

if(ret == 0){

1092

avahi_simple_poll_quit(simple_poll);

1032

avahi_simple_poll_quit(mc.simple_poll);

1093

1033

} else {

1094

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

1095

avahi_proto_to_af(proto),

1096

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

1034

if(not add_server(ip, port, interface,

1035

avahi_proto_to_af(proto))){

1097

1036

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

1098

1037

" list\n", name);

1099

1038

}

1112

1051

const char *domain,

1113

1052

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1114

1053

flags,

1115

void *mc){

1116

if(b == NULL){

1117

return;

1118

}

1054

AVAHI_GCC_UNUSED void* userdata){

1055

assert(b);

1119

1056

1120

1057

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

1121

1058

is removed from the LAN */

1129

1066

case AVAHI_BROWSER_FAILURE:

1130

1067

1131

1068

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

1132

avahi_strerror(avahi_server_errno

1133

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

1134

avahi_simple_poll_quit(simple_poll);

1069

avahi_strerror(avahi_server_errno(mc.server)));

1070

avahi_simple_poll_quit(mc.simple_poll);

1135

1071

return;

1136

1072

1137

1073

case AVAHI_BROWSER_NEW:

1140

1076

the callback function is called the Avahi server will free the

1141

1077

resolver for us. */

1142

1078

1143

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

1144

interface, protocol, name, type,

1145

domain, protocol, 0,

1146

resolve_callback, mc) == NULL)

1079

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

1080

name, type, domain, protocol, 0,

1081

resolve_callback, NULL) == NULL)

1147

1082

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

1148

1083

" %s\n", name,

1149

avahi_strerror(avahi_server_errno

1150

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

1084

avahi_strerror(avahi_server_errno(mc.server)));

1151

1085

break;

1152

1086

1153

1087

case AVAHI_BROWSER_REMOVE:

1172

1106

signal_received = sig;

1173

1107

int old_errno = errno;

1174

1108

/* set main loop to exit */

1175

if(simple_poll != NULL){

1176

avahi_simple_poll_quit(simple_poll);

1109

if(mc.simple_poll != NULL){

1110

avahi_simple_poll_quit(mc.simple_poll);

1177

1111

}

1178

1112

errno = old_errno;

1179

1113

}

1180

1114

1181

__attribute__((nonnull, warn_unused_result))

1182

1115

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

1183

1116

int ret;

1184

error_t ret_errno;

1185

1117

1186

1118

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

1187

1119

if(s < 0){

1188

ret_errno = errno;

1189

1120

perror_plus("socket");

1190

errno = ret_errno;

1191

1121

return false;

1192

1122

}

1193

1123

strcpy(ifr->ifr_name, ifname);

1194

1124

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1195

1125

if(ret == -1){

1196

1126

if(debug){

1197

ret_errno = errno;

1198

1127

perror_plus("ioctl SIOCGIFFLAGS");

1199

errno = ret_errno;

1200

1128

}

1201

1129

return false;

1202

1130

}

1203

1131

return true;

1204

1132

}

1205

1133

1206

__attribute__((nonnull, warn_unused_result))

1207

1134

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

1208

1135

1209

1136

/* Reject the loopback device */

1251

1178

* corresponds to an acceptable network device.

1252

1179

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

1253

1180

*/

1254

__attribute__((nonnull, warn_unused_result))

1255

1181

int good_interface(const struct dirent *if_entry){

1256

1182

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

1257

1183

return 0;

1273

1199

}

1274

1200

1275

1201

/*

1276

* This function determines if a network interface is up.

1277

*/

1278

__attribute__((nonnull, warn_unused_result))

1279

bool interface_is_up(const char *interface){

1280

struct ifreq ifr;

1281

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

1282

if(debug){

1283

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

1284

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

1285

}

1286

return false;

1287

}

1288

1289

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

1290

}

1291

1292

/*

1293

* This function determines if a network interface is running

1294

*/

1295

__attribute__((nonnull, warn_unused_result))

1296

bool interface_is_running(const char *interface){

1297

struct ifreq ifr;

1298

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

1299

if(debug){

1300

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

1301

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

1302

}

1303

return false;

1304

}

1305

1306

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

1307

}

1308

1309

__attribute__((nonnull, pure, warn_unused_result))

1202

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

1203

* corresponds to an acceptable network device which is up.

1204

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

1205

*/

1206

int up_interface(const struct dirent *if_entry){

1207

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

1208

return 0;

1209

}

1210

1211

struct ifreq ifr;

1212

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

1213

if(debug){

1214

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

1215

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

1216

}

1217

return 0;

1218

}

1219

1220

/* Reject down interfaces */

1221

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

1222

if(debug){

1223

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

1224

if_entry->d_name);

1225

}

1226

return 0;

1227

}

1228

1229

/* Reject non-running interfaces */

1230

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

1231

if(debug){

1232

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

1233

if_entry->d_name);

1234

}

1235

return 0;

1236

}

1237

1238

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

1239

return 0;

1240

}

1241

return 1;

1242

}

1243

1310

1244

int notdotentries(const struct dirent *direntry){

1311

1245

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

1312

1246

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

1319

1253

}

1320

1254

1321

1255

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

1322

__attribute__((nonnull, warn_unused_result))

1323

1256

int runnable_hook(const struct dirent *direntry){

1324

1257

int ret;

1325

1258

size_t sret;

1380

1313

return 1;

1381

1314

}

1382

1315

1383

__attribute__((nonnull, warn_unused_result))

1384

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1385

mandos_context *mc){

1316

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1386

1317

int ret;

1387

1318

struct timespec now;

1388

1319

struct timespec waited_time;

1389

1320

intmax_t block_time;

1390

1321

1391

1322

while(true){

1392

if(mc->current_server == NULL){

1393

if(debug){

1323

if(mc.current_server == NULL){

1324

if (debug){

1394

1325

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

1395

1326

" No timeout!\n");

1396

1327

}

1397

1328

ret = avahi_simple_poll_iterate(s, -1);

1398

1329

} else {

1399

if(debug){

1330

if (debug){

1400

1331

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

1401

1332

" it, or wait\n");

1402

1333

}

1409

1340

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

1410

1341

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

1411

1342

waited_time.tv_sec = (now.tv_sec

1412

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

1343

- mc.current_server->last_seen.tv_sec);

1413

1344

waited_time.tv_nsec = (now.tv_nsec

1414

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

1345

- mc.current_server->last_seen.tv_nsec);

1415

1346

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

1416

1347

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

1417

1348

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

1419

1350

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

1420

1351

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

1421

1352

1422

if(debug){

1353

if (debug){

1423

1354

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

1424

1355

block_time);

1425

1356

}

1426

1357

1427

1358

if(block_time <= 0){

1428

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

1429

mc->current_server->port,

1430

mc->current_server->if_index,

1431

mc->current_server->af, mc);

1359

ret = start_mandos_communication(mc.current_server->ip,

1360

mc.current_server->port,

1361

mc.current_server->if_index,

1362

mc.current_server->af);

1432

1363

if(ret == 0){

1433

avahi_simple_poll_quit(s);

1364

avahi_simple_poll_quit(mc.simple_poll);

1434

1365

return 0;

1435

1366

}

1436

1367

ret = clock_gettime(CLOCK_MONOTONIC,

1437

&mc->current_server->last_seen);

1368

&mc.current_server->last_seen);

1438

1369

if(ret == -1){

1439

1370

perror_plus("clock_gettime");

1440

1371

return -1;

1441

1372

}

1442

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

1373

mc.current_server = mc.current_server->next;

1443

1374

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

1444

1375

servers, but don't block */

1445

1376

}

1447

1378

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

1448

1379

}

1449

1380

if(ret != 0){

1450

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

1381

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

1451

1382

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

1452

1383

}

1453

1384

}

1454

1385

}

1455

1386

}

1456

1387

1457

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

1458

__attribute__((warn_unused_result))

1459

error_t raise_privileges(void){

1460

error_t old_errno = errno;

1461

error_t ret_errno = 0;

1462

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

1463

ret_errno = errno;

1464

perror_plus("seteuid");

1465

}

1466

errno = old_errno;

1467

return ret_errno;

1468

}

1469

1470

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

1471

__attribute__((warn_unused_result))

1472

error_t raise_privileges_permanently(void){

1473

error_t old_errno = errno;

1474

error_t ret_errno = raise_privileges();

1475

if(ret_errno != 0){

1476

errno = old_errno;

1477

return ret_errno;

1478

}

1479

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

1480

ret_errno = errno;

1481

perror_plus("seteuid");

1482

}

1483

errno = old_errno;

1484

return ret_errno;

1485

}

1486

1487

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

1488

__attribute__((warn_unused_result))

1489

error_t lower_privileges(void){

1490

error_t old_errno = errno;

1491

error_t ret_errno = 0;

1492

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

1493

ret_errno = errno;

1494

perror_plus("seteuid");

1495

}

1496

errno = old_errno;

1497

return ret_errno;

1498

}

1499

1500

/* Lower privileges permanently */

1501

__attribute__((warn_unused_result))

1502

error_t lower_privileges_permanently(void){

1503

error_t old_errno = errno;

1504

error_t ret_errno = 0;

1505

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

1506

ret_errno = errno;

1507

perror_plus("setuid");

1508

}

1509

errno = old_errno;

1510

return ret_errno;

1511

}

1512

1513

__attribute__((nonnull))

1514

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

1388

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

1515

1389

const float delay){

1516

1390

struct dirent **direntries;

1391

struct dirent *direntry;

1392

int ret;

1517

1393

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

1518

1394

alphasort);

1519

1395

if(numhooks == -1){

1520

if(errno == ENOENT){

1521

if(debug){

1522

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

1523

" found\n", hookdir);

1524

}

1525

} else {

1526

perror_plus("scandir");

1527

}

1396

perror_plus("scandir");

1528

1397

} else {

1529

struct dirent *direntry;

1530

int ret;

1531

1398

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

1532

1399

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

1533

1400

direntry = direntries[i];

1545

1412

if(hook_pid == 0){

1546

1413

/* Child */

1547

1414

/* Raise privileges */

1548

if(raise_privileges_permanently() != 0){

1549

perror_plus("Failed to raise privileges");

1550

_exit(EX_NOPERM);

1415

errno = 0;

1416

ret = seteuid(0);

1417

if(ret == -1){

1418

perror_plus("seteuid");

1419

}

1420

/* Raise privileges even more */

1421

errno = 0;

1422

ret = setuid(0);

1423

if(ret == -1){

1424

perror_plus("setuid");

1551

1425

}

1552

1426

/* Set group */

1553

1427

errno = 0;

1554

1428

ret = setgid(0);

1555

1429

if(ret == -1){

1556

1430

perror_plus("setgid");

1557

_exit(EX_NOPERM);

1558

1431

}

1559

1432

/* Reset supplementary groups */

1560

1433

errno = 0;

1561

1434

ret = setgroups(0, NULL);

1562

1435

if(ret == -1){

1563

1436

perror_plus("setgroups");

1564

_exit(EX_NOPERM);

1565

}

1566

ret = dup2(devnull, STDIN_FILENO);

1567

if(ret == -1){

1568

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

1569

_exit(EX_OSERR);

1570

}

1571

ret = close(devnull);

1572

if(ret == -1){

1573

perror_plus("close");

1574

_exit(EX_OSERR);

1575

}

1576

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1577

if(ret == -1){

1578

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

1579

_exit(EX_OSERR);

1580

}

1437

}

1438

dup2(devnull, STDIN_FILENO);

1439

close(devnull);

1440

dup2(STDERR_FILENO, STDOUT_FILENO);

1581

1441

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

1582

1442

if(ret == -1){

1583

1443

perror_plus("setenv");

1588

1448

perror_plus("setenv");

1589

1449

_exit(EX_OSERR);

1590

1450

}

1591

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

1451

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

1592

1452

if(ret == -1){

1593

1453

perror_plus("setenv");

1594

1454

_exit(EX_OSERR);

1599

1459

_exit(EX_OSERR);

1600

1460

}

1601

1461

char *delaystring;

1602

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

1462

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

1603

1463

if(ret == -1){

1604

1464

perror_plus("asprintf");

1605

1465

_exit(EX_OSERR);

1611

1471

_exit(EX_OSERR);

1612

1472

}

1613

1473

free(delaystring);

1614

if(connect_to != NULL){

1615

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

1616

if(ret == -1){

1617

perror_plus("setenv");

1618

_exit(EX_OSERR);

1619

}

1620

}

1621

1474

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

1622

1475

perror_plus("execl");

1623

1476

_exit(EXIT_FAILURE);

1658

1511

}

1659

1512

close(devnull);

1660

1513

}

1661

}

1662

1663

__attribute__((nonnull, warn_unused_result))

1664

error_t bring_up_interface(const char *const interface,

1665

const float delay){

1666

error_t old_errno = errno;

1667

int ret;

1668

struct ifreq network;

1669

unsigned int if_index = if_nametoindex(interface);

1670

if(if_index == 0){

1671

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

1672

errno = old_errno;

1673

return ENXIO;

1674

}

1675

1676

if(quit_now){

1677

errno = old_errno;

1678

return EINTR;

1679

}

1680

1681

if(not interface_is_up(interface)){

1682

error_t ret_errno = 0, ioctl_errno = 0;

1683

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

1684

ret_errno = errno;

1685

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

1686

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

1687

errno = old_errno;

1688

return ret_errno;

1689

}

1690

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

1691

1692

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

1693

if(sd == -1){

1694

ret_errno = errno;

1695

perror_plus("socket");

1696

errno = old_errno;

1697

return ret_errno;

1698

}

1699

1700

if(quit_now){

1701

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

1702

if(ret == -1){

1703

perror_plus("close");

1704

}

1705

errno = old_errno;

1706

return EINTR;

1707

}

1708

1709

if(debug){

1710

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

1711

interface);

1712

}

1713

1714

/* Raise privileges */

1715

ret_errno = raise_privileges();

1716

bool restore_loglevel = false;

1717

if(ret_errno != 0){

1718

perror_plus("Failed to raise privileges");

1719

}

1720

#ifdef __linux__

1721

int ret_linux;

1722

if(ret_errno == 0){

1723

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1724

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

1725

ret_linux = klogctl(8, NULL, 5);

1726

if(ret_linux == -1){

1727

perror_plus("klogctl");

1728

} else {

1729

restore_loglevel = true;

1730

}

1731

}

1732

#endif /* __linux__ */

1733

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

1734

ioctl_errno = errno;

1735

#ifdef __linux__

1736

if(restore_loglevel){

1737

ret_linux = klogctl(7, NULL, 0);

1738

if(ret_linux == -1){

1739

perror_plus("klogctl");

1740

}

1741

}

1742

#endif /* __linux__ */

1743

1744

/* If raise_privileges() succeeded above */

1745

if(ret_errno == 0){

1746

/* Lower privileges */

1747

ret_errno = lower_privileges();

1748

if(ret_errno != 0){

1749

errno = ret_errno;

1750

perror_plus("Failed to lower privileges");

1751

}

1752

}

1753

1754

/* Close the socket */

1755

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

1756

if(ret == -1){

1757

perror_plus("close");

1758

}

1759

1760

if(ret_setflags == -1){

1761

errno = ioctl_errno;

1762

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1763

errno = old_errno;

1764

return ioctl_errno;

1765

}

1766

} else if(debug){

1767

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

1768

interface);

1769

}

1770

1771

/* Sleep checking until interface is running.

1772

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

1773

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

1774

if(interface_is_running(interface)){

1775

break;

1776

}

1777

struct timespec sleeptime = { .tv_nsec = 250000000 };

1778

ret = nanosleep(&sleeptime, NULL);

1779

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

1780

perror_plus("nanosleep");

1781

}

1782

}

1783

1784

errno = old_errno;

1785

return 0;

1786

}

1787

1788

__attribute__((nonnull, warn_unused_result))

1789

error_t take_down_interface(const char *const interface){

1790

error_t old_errno = errno;

1791

struct ifreq network;

1792

unsigned int if_index = if_nametoindex(interface);

1793

if(if_index == 0){

1794

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

1795

errno = old_errno;

1796

return ENXIO;

1797

}

1798

if(interface_is_up(interface)){

1799

error_t ret_errno = 0, ioctl_errno = 0;

1800

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

1801

ret_errno = errno;

1802

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

1803

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

1804

errno = old_errno;

1805

return ret_errno;

1806

}

1807

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

1808

1809

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

1810

if(sd == -1){

1811

ret_errno = errno;

1812

perror_plus("socket");

1813

errno = old_errno;

1814

return ret_errno;

1815

}

1816

1817

if(debug){

1818

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

1819

interface);

1820

}

1821

1822

/* Raise privileges */

1823

ret_errno = raise_privileges();

1824

if(ret_errno != 0){

1825

perror_plus("Failed to raise privileges");

1826

}

1827

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

1828

ioctl_errno = errno;

1829

1830

/* If raise_privileges() succeeded above */

1831

if(ret_errno == 0){

1832

/* Lower privileges */

1833

ret_errno = lower_privileges();

1834

if(ret_errno != 0){

1835

errno = ret_errno;

1836

perror_plus("Failed to lower privileges");

1837

}

1838

}

1839

1840

/* Close the socket */

1841

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

1842

if(ret == -1){

1843

perror_plus("close");

1844

}

1845

1846

if(ret_setflags == -1){

1847

errno = ioctl_errno;

1848

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1849

errno = old_errno;

1850

return ioctl_errno;

1851

}

1852

} else if(debug){

1853

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

1854

interface);

1855

}

1856

1857

errno = old_errno;

1858

return 0;

1514

return true;

1859

1515

}

1860

1516

1861

1517

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

1862

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

1863

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

1864

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

1865

.interfaces = NULL, .interfaces_size = 0 };

1866

1518

AvahiSServiceBrowser *sb = NULL;

1867

error_t ret_errno;

1519

int error;

1868

1520

int ret;

1869

1521

intmax_t tmpmax;

1870

1522

char *tmp;

1871

1523

int exitcode = EXIT_SUCCESS;

1872

char *interfaces_to_take_down = NULL;

1873

size_t interfaces_to_take_down_size = 0;

1524

const char *interface = "";

1525

struct ifreq network;

1526

int sd = -1;

1527

bool take_down_interface = false;

1528

uid_t uid;

1529

gid_t gid;

1874

1530

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

1875

1531

bool tempdir_created = false;

1876

1532

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1877

1533

const char *seckey = PATHDIR "/" SECKEY;

1878

1534

const char *pubkey = PATHDIR "/" PUBKEY;

1879

char *interfaces_hooks = NULL;

1880

1535

1881

1536

bool gnutls_initialized = false;

1882

1537

bool gpgme_initialized = false;

1944

1599

.group = 2 },

1945

1600

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

1946

1601

.arg = "SECONDS",

1947

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

1602

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

1948

1603

.group = 2 },

1949

1604

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

1950

1605

.arg = "DIR",

1973

1628

connect_to = arg;

1974

1629

break;

1975

1630

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

1976

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

1977

arg, (int)',');

1978

if(ret_errno != 0){

1979

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

1980

}

1631

interface = arg;

1981

1632

break;

1982

1633

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

1983

1634

seckey = arg;

2060

1711

/* Work around Debian bug #633582:

2061

1712

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

2062

1713

2063

/* Re-raise privileges */

2064

ret_errno = raise_privileges();

2065

if(ret_errno != 0){

2066

errno = ret_errno;

2067

perror_plus("Failed to raise privileges");

1714

/* Re-raise priviliges */

1715

errno = 0;

1716

ret = seteuid(0);

1717

if(ret == -1){

1718

perror_plus("seteuid");

2068

1719

} else {

2069

1720

struct stat st;

2070

1721

2111

1762

}

2112

1763

2113

1764

/* Lower privileges */

2114

ret_errno = lower_privileges();

2115

if(ret_errno != 0){

2116

errno = ret_errno;

2117

perror_plus("Failed to lower privileges");

2118

}

2119

}

2120

}

2121

2122

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

2123

{

2124

char *interface = NULL;

2125

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

2126

interface))){

2127

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

2128

and if_nametoindex(interface) == 0){

2129

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

2130

fprintf_plus(stderr, "Not using nonexisting interface"

2131

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

2132

}

2133

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

2134

interface = NULL;

1765

errno = 0;

1766

ret = seteuid(uid);

1767

if(ret == -1){

1768

perror_plus("seteuid");

2135

1769

}

2136

1770

}

2137

1771

}

2138

1772

2139

1773

/* Run network hooks */

2140

{

2141

if(mc.interfaces != NULL){

2142

interfaces_hooks = malloc(mc.interfaces_size);

2143

if(interfaces_hooks == NULL){

2144

perror_plus("malloc");

2145

goto end;

2146

}

2147

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

2148

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

2149

}

2150

run_network_hooks("start", interfaces_hooks != NULL ?

2151

interfaces_hooks : "", delay);

1774

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

1775

goto end;

2152

1776

}

2153

1777

2154

1778

if(not debug){

2155

1779

avahi_set_log_function(empty_log);

2156

1780

}

2157

1781

1782

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

1783

struct dirent **direntries;

1784

/* First look for interfaces that are up */

1785

ret = scandir(sys_class_net, &direntries, up_interface,

1786

alphasort);

1787

if(ret == 0){

1788

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

1789

free(direntries);

1790

ret = scandir(sys_class_net, &direntries, good_interface,

1791

alphasort);

1792

}

1793

if(ret >= 1){

1794

/* Pick the first interface returned */

1795

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

1796

if(debug){

1797

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

1798

}

1799

if(interface == NULL){

1800

perror_plus("malloc");

1801

free(direntries);

1802

exitcode = EXIT_FAILURE;

1803

goto end;

1804

}

1805

free(direntries);

1806

} else {

1807

free(direntries);

1808

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

1809

exitcode = EXIT_FAILURE;

1810

goto end;

1811

}

1812

}

1813

2158

1814

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

2159

1815

from the signal handler */

2160

1816

/* Initialize the pseudo-RNG for Avahi */

2161

1817

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

2162

simple_poll = avahi_simple_poll_new();

2163

if(simple_poll == NULL){

1818

mc.simple_poll = avahi_simple_poll_new();

1819

if(mc.simple_poll == NULL){

2164

1820

fprintf_plus(stderr,

2165

1821

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

2166

1822

exitcode = EX_UNAVAILABLE;

2230

1886

}

2231

1887

}

2232

1888

2233

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

2234

if(mc.interfaces == NULL){

2235

struct dirent **direntries;

2236

/* Look for any good interfaces */

2237

ret = scandir(sys_class_net, &direntries, good_interface,

2238

alphasort);

2239

if(ret >= 1){

2240

/* Add all found interfaces to interfaces list */

2241

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

2242

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

2243

direntries[i]->d_name);

2244

if(ret_errno != 0){

2245

errno = ret_errno;

2246

perror_plus("argz_add");

2247

continue;

2248

}

2249

if(debug){

2250

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

2251

direntries[i]->d_name);

2252

}

2253

}

2254

free(direntries);

2255

} else {

2256

free(direntries);

2257

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

2258

exitcode = EXIT_FAILURE;

2259

goto end;

2260

}

2261

}

2262

2263

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

2264

{

2265

char *interface = NULL;

2266

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

2267

interface))){

2268

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

2269

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

2270

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

2271

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

2272

interface);

2273

interface = NULL;

2274

while((interface = argz_next(mc.interfaces,

2275

mc.interfaces_size, interface))){

2276

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

2277

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

2278

interface);

2279

interface = NULL;

1889

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

1890

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

1891

if_index = (AvahiIfIndex) if_nametoindex(interface);

1892

if(if_index == 0){

1893

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

1894

exitcode = EX_UNAVAILABLE;

1895

goto end;

1896

}

1897

1898

if(quit_now){

1899

goto end;

1900

}

1901

1902

/* Re-raise priviliges */

1903

errno = 0;

1904

ret = seteuid(0);

1905

if(ret == -1){

1906

perror_plus("seteuid");

1907

}

1908

1909

#ifdef __linux__

1910

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1911

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

1912

ret = klogctl(8, NULL, 5);

1913

bool restore_loglevel = true;

1914

if(ret == -1){

1915

restore_loglevel = false;

1916

perror_plus("klogctl");

1917

}

1918

#endif /* __linux__ */

1919

1920

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1921

if(sd < 0){

1922

perror_plus("socket");

1923

exitcode = EX_OSERR;

1924

#ifdef __linux__

1925

if(restore_loglevel){

1926

ret = klogctl(7, NULL, 0);

1927

if(ret == -1){

1928

perror_plus("klogctl");

1929

}

1930

}

1931

#endif /* __linux__ */

1932

/* Lower privileges */

1933

errno = 0;

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

1938

goto end;

1939

}

1940

strcpy(network.ifr_name, interface);

1941

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

1942

if(ret == -1){

1943

perror_plus("ioctl SIOCGIFFLAGS");

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

1949

}

1950

}

1951

#endif /* __linux__ */

1952

exitcode = EX_OSERR;

1953

/* Lower privileges */

1954

errno = 0;

1955

ret = seteuid(uid);

1956

if(ret == -1){

1957

perror_plus("seteuid");

1958

}

1959

goto end;

1960

}

1961

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

1962

network.ifr_flags |= IFF_UP;

1963

take_down_interface = true;

1964

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

1965

if(ret == -1){

1966

take_down_interface = false;

1967

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1968

exitcode = EX_OSERR;

1969

#ifdef __linux__

1970

if(restore_loglevel){

1971

ret = klogctl(7, NULL, 0);

1972

if(ret == -1){

1973

perror_plus("klogctl");

2280

1974

}

2281

1975

}

1976

#endif /* __linux__ */

1977

/* Lower privileges */

1978

errno = 0;

1979

ret = seteuid(uid);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

goto end;

1984

}

1985

}

1986

/* Sleep checking until interface is running.

1987

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

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCGIFFLAGS");

1992

} else if(network.ifr_flags & IFF_RUNNING){

2282

1993

break;

2283

1994

}

2284

bool interface_was_up = interface_is_up(interface);

2285

errno = bring_up_interface(interface, delay);

2286

if(not interface_was_up){

2287

if(errno != 0){

2288

perror_plus("Failed to bring up interface");

2289

} else {

2290

errno = argz_add(&interfaces_to_take_down,

2291

&interfaces_to_take_down_size,

2292

interface);

2293

if(errno != 0){

2294

perror_plus("argz_add");

2295

}

2296

}

2297

}

2298

}

2299

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

2300

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

2301

}

2302

}

2303

2304

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

2305

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

2306

if(debug){

2307

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

2308

mc.interfaces);

2309

}

2310

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

1995

struct timespec sleeptime = { .tv_nsec = 250000000 };

1996

ret = nanosleep(&sleeptime, NULL);

1997

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

1998

perror_plus("nanosleep");

1999

}

2000

}

2001

if(not take_down_interface){

2002

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

2003

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

2004

if(ret == -1){

2005

perror_plus("close");

2006

}

2007

}

2008

#ifdef __linux__

2009

if(restore_loglevel){

2010

/* Restores kernel loglevel to default */

2011

ret = klogctl(7, NULL, 0);

2012

if(ret == -1){

2013

perror_plus("klogctl");

2014

}

2015

}

2016

#endif /* __linux__ */

2017

/* Lower privileges */

2018

errno = 0;

2019

/* Lower privileges */

2020

ret = seteuid(uid);

2021

if(ret == -1){

2022

perror_plus("seteuid");

2023

}

2311

2024

}

2312

2025

2313

2026

if(quit_now){

2314

2027

goto end;

2315

2028

}

2316

2029

2317

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

2030

ret = init_gnutls_global(pubkey, seckey);

2318

2031

if(ret == -1){

2319

2032

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

2320

2033

exitcode = EX_UNAVAILABLE;

2337

2050

goto end;

2338

2051

}

2339

2052

2340

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

2053

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

2341

2054

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

2342

2055

exitcode = EX_UNAVAILABLE;

2343

2056

goto end;

2353

2066

/* Connect directly, do not use Zeroconf */

2354

2067

/* (Mainly meant for debugging) */

2355

2068

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

2356

2357

2069

if(address == NULL){

2358

2070

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

2359

2071

exitcode = EX_USAGE;

2364

2076

goto end;

2365

2077

}

2366

2078

2367

in_port_t port;

2079

uint16_t port;

2368

2080

errno = 0;

2369

2081

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

2370

2082

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

2371

or tmpmax != (in_port_t)tmpmax){

2083

or tmpmax != (uint16_t)tmpmax){

2372

2084

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

2373

2085

exitcode = EX_USAGE;

2374

2086

goto end;

2375

2087

}

2376

2088

2377

2089

if(quit_now){

2378

2090

goto end;

2379

2091

}

2380

2092

2381

port = (in_port_t)tmpmax;

2093

port = (uint16_t)tmpmax;

2382

2094

*address = '\0';

2383

2095

/* Colon in address indicates IPv6 */

2384

2096

int af;

2400

2112

}

2401

2113

2402

2114

while(not quit_now){

2403

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

2404

&mc);

2115

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

2405

2116

if(quit_now or ret == 0){

2406

2117

break;

2407

2118

}

2409

2120

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

2410

2121

(int)retry_interval);

2411

2122

}

2412

sleep((unsigned int)retry_interval);

2123

sleep((int)retry_interval);

2413

2124

}

2414

2125

2415

if(not quit_now){

2126

if (not quit_now){

2416

2127

exitcode = EXIT_SUCCESS;

2417

2128

}

2418

2129

2433

2144

config.publish_domain = 0;

2434

2145

2435

2146

/* Allocate a new server */

2436

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2437

&config, NULL, NULL, &ret_errno);

2147

mc.server = avahi_server_new(avahi_simple_poll_get

2148

(mc.simple_poll), &config, NULL,

2149

NULL, &error);

2438

2150

2439

2151

/* Free the Avahi configuration data */

2440

2152

avahi_server_config_free(&config);

2443

2155

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

2444

2156

if(mc.server == NULL){

2445

2157

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

2446

avahi_strerror(ret_errno));

2158

avahi_strerror(error));

2447

2159

exitcode = EX_UNAVAILABLE;

2448

2160

goto end;

2449

2161

}

2455

2167

/* Create the Avahi service browser */

2456

2168

sb = avahi_s_service_browser_new(mc.server, if_index,

2457

2169

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2458

NULL, 0, browse_callback,

2459

(void *)&mc);

2170

NULL, 0, browse_callback, NULL);

2460

2171

if(sb == NULL){

2461

2172

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

2462

2173

avahi_strerror(avahi_server_errno(mc.server)));

2474

2185

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

2475

2186

}

2476

2187

2477

ret = avahi_loop_with_timeout(simple_poll,

2478

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

2188

ret = avahi_loop_with_timeout(mc.simple_poll,

2189

(int)(retry_interval * 1000));

2479

2190

if(debug){

2480

2191

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

2481

2192

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

2488

2199

}

2489

2200

2490

2201

/* Cleanup things */

2491

free(mc.interfaces);

2492

2493

2202

if(sb != NULL)

2494

2203

avahi_s_service_browser_free(sb);

2495

2204

2496

2205

if(mc.server != NULL)

2497

2206

avahi_server_free(mc.server);

2498

2207

2499

if(simple_poll != NULL)

2500

avahi_simple_poll_free(simple_poll);

2208

if(mc.simple_poll != NULL)

2209

avahi_simple_poll_free(mc.simple_poll);

2501

2210

2502

2211

if(gnutls_initialized){

2503

2212

gnutls_certificate_free_credentials(mc.cred);

2520

2229

}

2521

2230

}

2522

2231

2523

/* Re-raise privileges */

2232

/* Run network hooks */

2233

run_network_hooks("stop", interface, delay);

2234

2235

/* Re-raise priviliges */

2524

2236

{

2525

ret_errno = raise_privileges();

2526

if(ret_errno != 0){

2527

perror_plus("Failed to raise privileges");

2528

} else {

2529

2530

/* Run network hooks */

2531

run_network_hooks("stop", interfaces_hooks != NULL ?

2532

interfaces_hooks : "", delay);

2533

2534

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

2535

{

2536

char *interface = NULL;

2537

while((interface=argz_next(interfaces_to_take_down,

2538

interfaces_to_take_down_size,

2539

interface))){

2540

ret_errno = take_down_interface(interface);

2541

if(ret_errno != 0){

2542

errno = ret_errno;

2543

perror_plus("Failed to take down interface");

2544

}

2545

}

2546

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

2547

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

2548

" down\n");

2549

}

2550

}

2551

}

2552

ret_errno = lower_privileges_permanently();

2553

if(ret_errno != 0){

2554

perror_plus("Failed to lower privileges permanently");

2555

}

2556

}

2557

2558

free(interfaces_to_take_down);

2559

free(interfaces_hooks);

2237

errno = 0;

2238

ret = seteuid(0);

2239

if(ret == -1){

2240

perror_plus("seteuid");

2241

}

2242

2243

/* Take down the network interface */

2244

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

2245

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

2246

if(ret == -1){

2247

perror_plus("ioctl SIOCGIFFLAGS");

2248

} else if(network.ifr_flags & IFF_UP){

2249

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

2250

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

2251

if(ret == -1){

2252

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2253

}

2254

}

2255

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

2256

if(ret == -1){

2257

perror_plus("close");

2258

}

2259

}

2260

}

2261

/* Lower privileges permanently */

2262

errno = 0;

2263

ret = setuid(uid);

2264

if(ret == -1){

2265

perror_plus("setuid");

2266

}

2560

2267

2561

2268

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

2562

2269

if(tempdir_created){

2564

2271

struct dirent *direntry = NULL;

2565

2272

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

2566

2273

alphasort);

2567

if(numentries > 0){

2274

if (numentries > 0){

2568

2275

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

2569

2276

direntry = direntries[i];

2570

2277

char *fullname = NULL;

2585

2292

2586

2293

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

2587

2294

free(direntries);

2588

if(numentries == -1){

2295

if (numentries == -1){

2589

2296

perror_plus("scandir");

2590

2297

}

2591

2298

ret = rmdir(tempdir);