/mandos/trunk : revision 237.4.33

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

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*

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* Everything else is

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*

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

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* 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() */

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

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

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

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

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strtof(), abort() */

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*/

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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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*/

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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() */

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

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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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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#ifdef __linux__

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

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

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139

char *connect_to = NULL;

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140

const char *hookdir = HOOKDIR;

141

uid_t uid = 65534;

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gid_t gid = 65534;

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143

138

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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;

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149

int af;

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struct timespec last_seen;

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154

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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159

unsigned int dh_bits;

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161

const char *priority;

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162

gpgme_ctx_t ctx;

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163

server *current_server;

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char *interfaces;

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size_t interfaces_size;

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166

} mandos_context;

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/* 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 };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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170

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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173

170

174

/* Function to use when printing errors */

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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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}

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

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

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va_list ap;

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va_start (ap, format);

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208

}

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

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

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int af){

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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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213

int ret;

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214

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

208

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if(new_server == NULL){

209

216

perror_plus("malloc");

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return -1;

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return false;

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}

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

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.port = port,

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

218

return -1;

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return false;

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226

}

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/* Special case of first server */

221

if (mc.current_server == NULL){

228

if(*current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

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*current_server = new_server;

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

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} else {

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new_server->next = mc.current_server;

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

234

new_server->next = *current_server;

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

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new_server->prev->next = new_server;

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mc.current_server->prev = new_server;

237

(*current_server)->prev = new_server;

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}

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

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

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if(ret == -1){

234

241

perror_plus("clock_gettime");

235

return -1;

242

return false;

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243

}

237

return 0;

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return true;

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245

}

239

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240

247

/*

241

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* Initialize GPGME.

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*/

243

250

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

244

const char *tempdir){

251

const char *tempdir, mandos_context *mc){

245

252

gpgme_error_t rc;

246

253

gpgme_engine_info_t engine_info;

247

254

248

249

255

/*

250

256

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

251

257

*/

267

273

return false;

268

274

}

269

275

270

rc = gpgme_op_import(mc.ctx, pgp_data);

276

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

271

277

if(rc != GPG_ERR_NO_ERROR){

272

278

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

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279

gpgme_strsource(rc), gpgme_strerror(rc));

317

323

}

318

324

319

325

/* Create new GPGME "context" */

320

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

326

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

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if(rc != GPG_ERR_NO_ERROR){

322

328

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

323

329

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

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344

*/

339

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

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size_t crypto_size,

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char **plaintext){

347

char **plaintext,

348

mandos_context *mc){

342

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gpgme_data_t dh_crypto, dh_plain;

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gpgme_error_t rc;

344

351

ssize_t ret;

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

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data buffer */

373

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

380

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

374

381

if(rc != GPG_ERR_NO_ERROR){

375

382

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

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gpgme_strsource(rc), gpgme_strerror(rc));

377

384

plaintext_length = -1;

378

385

if(debug){

379

386

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

381

388

if(result == NULL){

382

389

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

383

390

} else {

461

468

}

462

469

463

470

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

466

472

if(ret == NULL)

467

473

ret = "(unknown)";

468

474

return ret;

475

481

}

476

482

477

483

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

479

486

int ret;

480

487

481

488

if(debug){

498

505

}

499

506

500

507

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

509

if(ret != GNUTLS_E_SUCCESS){

503

510

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

504

511

safer_gnutls_strerror(ret));

514

521

}

515

522

516

523

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

518

525

GNUTLS_OPENPGP_FMT_BASE64);

519

526

if(ret != GNUTLS_E_SUCCESS){

520

527

fprintf_plus(stderr,

526

533

}

527

534

528

535

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

530

537

if(ret != GNUTLS_E_SUCCESS){

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538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

539

" initialization: %s\n",

533

540

safer_gnutls_strerror(ret));

534

541

goto globalfail;

535

542

}

536

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

543

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

537

544

if(ret != GNUTLS_E_SUCCESS){

538

545

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

539

546

safer_gnutls_strerror(ret));

540

547

goto globalfail;

541

548

}

542

549

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

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

544

551

545

552

return 0;

546

553

547

554

globalfail:

548

555

549

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

550

557

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

552

559

return -1;

553

560

}

554

561

555

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

556

564

int ret;

557

565

/* GnuTLS session creation */

558

566

do {

570

578

{

571

579

const char *err;

572

580

do {

573

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

581

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

574

582

if(quit_now){

575

583

gnutls_deinit(*session);

576

584

return -1;

587

595

588

596

do {

589

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

598

mc->cred);

591

599

if(quit_now){

592

600

gnutls_deinit(*session);

593

601

return -1;

603

611

/* ignore client certificate if any. */

604

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

613

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

607

615

608

616

return 0;

609

617

}

613

621

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

614

622

615

623

/* Called when a Mandos server is found */

616

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

624

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

617

625

AvahiIfIndex if_index,

618

int af){

626

int af, mandos_context *mc){

619

627

int ret, tcp_sd = -1;

620

628

ssize_t sret;

621

629

union {

651

659

return -1;

652

660

}

653

661

654

ret = init_gnutls_session(&session);

662

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

663

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

664

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

665

bool match = false;

666

{

667

char *interface = NULL;

668

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

669

interface))){

670

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

671

match = true;

672

break;

673

}

674

}

675

}

676

if(not match){

677

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

678

connect to the server */

679

if(debug){

680

char interface[IF_NAMESIZE];

681

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

682

perror_plus("if_indextoname");

683

} else {

684

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

685

" \"%s\"\n",

686

if_indextoname((unsigned int)if_index,

687

interface));

688

}

689

}

690

return -1;

691

}

692

}

693

694

ret = init_gnutls_session(&session, mc);

655

695

if(ret != 0){

656

696

return -1;

657

697

}

658

698

659

699

if(debug){

660

700

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

661

PRIu16 "\n", ip, port);

701

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

662

702

}

663

703

664

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

695

735

goto mandos_end;

696

736

}

697

737

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

738

to.in6.sin6_port = htons(port);

702

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

740

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

704

741

-Wunreachable-code*/

728

765

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

729

766

perror_plus("if_indextoname");

730

767

} else {

731

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

732

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

768

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

769

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

733

770

}

734

771

} else {

735

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

736

ip, port);

772

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

773

ip, (uintmax_t)port);

737

774

}

738

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

817

854

goto mandos_end;

818

855

}

819

856

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

857

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

858

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

859

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

860

gnutls_transport_set_ptr(session,

861

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

862

823

863

if(quit_now){

824

864

errno = EINTR;

929

969

if(buffer_length > 0){

930

970

ssize_t decrypted_buffer_size;

931

971

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

972

&decrypted_buffer, mc);

933

973

if(decrypted_buffer_size >= 0){

934

974

935

975

written = 0;

996

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1038

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1039

void* mc){

1040

if(r == NULL){

1041

return;

1042

}

1001

1043

1002

1044

/* Called whenever a service has been resolved successfully or

1003

1045

timed out */

1012

1054

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

1013

1055

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

1014

1056

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1057

avahi_strerror(avahi_server_errno

1058

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

1016

1059

break;

1017

1060

1018

1061

case AVAHI_RESOLVER_FOUND:

1024

1067

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

1025

1068

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

1026

1069

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1070

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

1071

interface,

1072

avahi_proto_to_af(proto),

1073

mc);

1029

1074

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1075

avahi_simple_poll_quit(simple_poll);

1031

1076

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1077

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

1078

avahi_proto_to_af(proto),

1079

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

1080

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

1081

" list\n", name);

1082

}

1034

1083

}

1035

1084

}

1036

1085

}

1046

1095

const char *domain,

1047

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1097

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1098

void* mc){

1099

if(b == NULL){

1100

return;

1101

}

1051

1102

1052

1103

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

1053

1104

is removed from the LAN */

1061

1112

case AVAHI_BROWSER_FAILURE:

1062

1113

1063

1114

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1115

avahi_strerror(avahi_server_errno

1116

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

1117

avahi_simple_poll_quit(simple_poll);

1066

1118

return;

1067

1119

1068

1120

case AVAHI_BROWSER_NEW:

1071

1123

the callback function is called the Avahi server will free the

1072

1124

resolver for us. */

1073

1125

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1126

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

1127

interface, protocol, name, type,

1128

domain, protocol, 0,

1129

resolve_callback, mc) == NULL)

1077

1130

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

1078

1131

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1132

avahi_strerror(avahi_server_errno

1133

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

1080

1134

break;

1081

1135

1082

1136

case AVAHI_BROWSER_REMOVE:

1101

1155

signal_received = sig;

1102

1156

int old_errno = errno;

1103

1157

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1158

if(simple_poll != NULL){

1159

avahi_simple_poll_quit(simple_poll);

1106

1160

}

1107

1161

errno = old_errno;

1108

1162

}

1109

1163

1110

1164

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

1111

1165

int ret;

1166

error_t ret_errno;

1112

1167

1113

1168

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

1114

1169

if(s < 0){

1170

ret_errno = errno;

1115

1171

perror_plus("socket");

1172

errno = ret_errno;

1116

1173

return false;

1117

1174

}

1118

1175

strcpy(ifr->ifr_name, ifname);

1119

1176

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1177

if(ret == -1){

1121

1178

if(debug){

1179

ret_errno = errno;

1122

1180

perror_plus("ioctl SIOCGIFFLAGS");

1181

errno = ret_errno;

1123

1182

}

1124

1183

return false;

1125

1184

}

1194

1253

}

1195

1254

1196

1255

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

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

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

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

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1256

* This function determines if a network interface is up.

1257

*/

1258

bool interface_is_up(const char *interface){

1259

struct ifreq ifr;

1260

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

1261

if(debug){

1262

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

1263

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

1264

}

1265

return false;

1266

}

1267

1268

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

1269

}

1270

1271

/*

1272

* This function determines if a network interface is running

1273

*/

1274

bool interface_is_running(const char *interface){

1275

struct ifreq ifr;

1276

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

1277

if(debug){

1278

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

1279

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

1280

}

1281

return false;

1282

}

1283

1284

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

1237

1285

}

1238

1286

1239

1287

int notdotentries(const struct dirent *direntry){

1301

1349

}

1302

1350

return 0;

1303

1351

}

1352

if(debug){

1353

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1354

direntry->d_name);

1355

}

1304

1356

return 1;

1305

1357

}

1306

1358

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

mandos_context *mc){

1308

1361

int ret;

1309

1362

struct timespec now;

1310

1363

struct timespec waited_time;

1311

1364

intmax_t block_time;

1312

1365

1313

1366

while(true){

1314

if(mc.current_server == NULL){

1367

if(mc->current_server == NULL){

1315

1368

if (debug){

1316

1369

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

1317

1370

" No timeout!\n");

1331

1384

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

1332

1385

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

1333

1386

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

1387

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

1335

1388

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

1389

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

1337

1390

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

1338

1391

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

1339

1392

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

1347

1400

}

1348

1401

1349

1402

if(block_time <= 0){

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

1403

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

1404

mc->current_server->port,

1405

mc->current_server->if_index,

1406

mc->current_server->af, mc);

1354

1407

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

1408

avahi_simple_poll_quit(s);

1356

1409

return 0;

1357

1410

}

1358

1411

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

1412

&mc->current_server->last_seen);

1360

1413

if(ret == -1){

1361

1414

perror_plus("clock_gettime");

1362

1415

return -1;

1363

1416

}

1364

mc.current_server = mc.current_server->next;

1417

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

1365

1418

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

1366

1419

servers, but don't block */

1367

1420

}

1376

1429

}

1377

1430

}

1378

1431

1432

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

1433

error_t raise_privileges(void){

1434

error_t old_errno = errno;

1435

error_t ret_errno = 0;

1436

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

1437

ret_errno = errno;

1438

perror_plus("seteuid");

1439

}

1440

errno = old_errno;

1441

return ret_errno;

1442

}

1443

1444

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

1445

error_t raise_privileges_permanently(void){

1446

error_t old_errno = errno;

1447

error_t ret_errno = raise_privileges();

1448

if(ret_errno != 0){

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

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

1453

ret_errno = errno;

1454

perror_plus("seteuid");

1455

}

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

1460

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

1461

error_t lower_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

/* Lower privileges permanently */

1473

error_t lower_privileges_permanently(void){

1474

error_t old_errno = errno;

1475

error_t ret_errno = 0;

1476

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

1477

ret_errno = errno;

1478

perror_plus("setuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1379

1484

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

1380

1485

const float delay){

1381

1486

struct dirent **direntries;

1384

1489

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

1385

1490

alphasort);

1386

1491

if(numhooks == -1){

1387

perror_plus("scandir");

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

1499

}

1388

1500

} else {

1389

1501

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

1390

1502

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

1402

1514

pid_t hook_pid = fork();

1403

1515

if(hook_pid == 0){

1404

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1405

1531

dup2(devnull, STDIN_FILENO);

1406

1532

close(devnull);

1407

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1408

1534

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

1409

1535

if(ret == -1){

1410

1536

perror_plus("setenv");

1411

return false;

1537

_exit(EX_OSERR);

1412

1538

}

1413

1539

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

1414

1540

if(ret == -1){

1415

1541

perror_plus("setenv");

1416

return false;

1542

_exit(EX_OSERR);

1417

1543

}

1418

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

1544

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

1419

1545

if(ret == -1){

1420

1546

perror_plus("setenv");

1421

return false;

1547

_exit(EX_OSERR);

1422

1548

}

1423

1549

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

1424

1550

if(ret == -1){

1425

1551

perror_plus("setenv");

1426

return false;

1552

_exit(EX_OSERR);

1427

1553

}

1428

1554

char *delaystring;

1429

1555

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

1430

1556

if(ret == -1){

1431

1557

perror_plus("asprintf");

1432

return false;

1558

_exit(EX_OSERR);

1433

1559

}

1434

1560

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

1435

1561

if(ret == -1){

1436

1562

free(delaystring);

1437

1563

perror_plus("setenv");

1438

return false;

1564

_exit(EX_OSERR);

1439

1565

}

1440

1566

free(delaystring);

1441

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

1442

perror_plus("execl");

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

1443

1578

} else {

1444

1579

int status;

1445

1580

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

1469

1604

}

1470

1605

}

1471

1606

free(fullname);

1472

if(quit_now){

1473

break;

1607

if(debug){

1608

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

1609

direntry->d_name);

1474

1610

}

1475

1611

}

1476

1612

close(devnull);

1478

1614

return true;

1479

1615

}

1480

1616

1617

error_t bring_up_interface(const char *const interface,

1618

const float delay){

1619

int sd = -1;

1620

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

1623

struct ifreq network;

1624

unsigned int if_index = if_nametoindex(interface);

1625

if(if_index == 0){

1626

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

1627

errno = old_errno;

1628

return ENXIO;

1629

}

1630

1631

if(quit_now){

1632

errno = old_errno;

1633

return EINTR;

1634

}

1635

1636

if(not interface_is_up(interface)){

1637

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

1638

ret_errno = errno;

1639

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

1640

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

1641

return ret_errno;

1642

}

1643

network.ifr_flags |= IFF_UP;

1644

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

1647

ret_errno = errno;

1648

perror_plus("socket");

1649

errno = old_errno;

1650

return ret_errno;

1651

}

1652

1653

if(quit_now){

1654

close(sd);

1655

errno = old_errno;

1656

return EINTR;

1657

}

1658

1659

if(debug){

1660

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

1661

interface);

1662

}

1663

1664

/* Raise priviliges */

1665

raise_privileges();

1666

1667

#ifdef __linux__

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

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

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

1675

}

1676

#endif /* __linux__ */

1677

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

1678

ret_errno = errno;

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret_linux = klogctl(7, NULL, 0);

1682

if(ret_linux == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

1688

/* Lower privileges */

1689

lower_privileges();

1690

1691

/* Close the socket */

1692

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

1693

if(ret == -1){

1694

perror_plus("close");

1695

}

1696

1697

if(ret_setflags == -1){

1698

errno = ret_errno;

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1700

errno = old_errno;

1701

return ret_errno;

1702

}

1703

} else if(debug){

1704

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

1705

interface);

1706

}

1707

1708

/* Sleep checking until interface is running.

1709

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

1710

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

1711

if(interface_is_running(interface)){

1712

break;

1713

}

1714

struct timespec sleeptime = { .tv_nsec = 250000000 };

1715

ret = nanosleep(&sleeptime, NULL);

1716

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

1717

perror_plus("nanosleep");

1718

}

1719

}

1720

1721

errno = old_errno;

1722

return 0;

1723

}

1724

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

1730

struct ifreq network;

1731

unsigned int if_index = if_nametoindex(interface);

1732

if(if_index == 0){

1733

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

1734

errno = old_errno;

1735

return ENXIO;

1736

}

1737

if(interface_is_up(interface)){

1738

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

1739

ret_errno = errno;

1740

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

1741

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

1742

return ret_errno;

1743

}

1744

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

1745

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

1748

ret_errno = errno;

1749

perror_plus("socket");

1750

errno = old_errno;

1751

return ret_errno;

1752

}

1753

1754

if(debug){

1755

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

1756

interface);

1757

}

1758

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

1767

1768

/* Close the socket */

1769

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

1770

if(ret == -1){

1771

perror_plus("close");

1772

}

1773

1774

if(ret_setflags == -1){

1775

errno = ret_errno;

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1777

errno = old_errno;

1778

return ret_errno;

1779

}

1780

} else if(debug){

1781

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

1782

interface);

1783

}

1784

1785

errno = old_errno;

1786

return 0;

1787

}

1788

1481

1789

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

1790

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

1791

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

1792

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

1793

.interfaces = NULL, .interfaces_size = 0 };

1482

1794

AvahiSServiceBrowser *sb = NULL;

1483

int error;

1795

error_t ret_errno;

1484

1796

int ret;

1485

1797

intmax_t tmpmax;

1486

1798

char *tmp;

1487

1799

int exitcode = EXIT_SUCCESS;

1488

const char *interface = "";

1489

struct ifreq network;

1490

int sd = -1;

1491

bool take_down_interface = false;

1492

uid_t uid;

1493

gid_t gid;

1800

char *interfaces_to_take_down = NULL;

1801

size_t interfaces_to_take_down_size = 0;

1494

1802

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

1495

1803

bool tempdir_created = false;

1496

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1497

1805

const char *seckey = PATHDIR "/" SECKEY;

1498

1806

const char *pubkey = PATHDIR "/" PUBKEY;

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1499

1809

1500

1810

bool gnutls_initialized = false;

1501

1811

bool gpgme_initialized = false;

1563

1873

.group = 2 },

1564

1874

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

1565

1875

.arg = "SECONDS",

1566

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

1876

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

1567

1877

.group = 2 },

1568

1878

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

1569

1879

.arg = "DIR",

1592

1902

connect_to = arg;

1593

1903

break;

1594

1904

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

1595

interface = arg;

1905

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

1906

arg, (int)',');

1907

if(ret_errno != 0){

1908

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

1909

}

1596

1910

break;

1597

1911

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

1598

1912

seckey = arg;

1641

1955

argp_state_help(state, state->out_stream,

1642

1956

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1643

1957

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

1644

fprintf_plus(state->out_stream,

1645

"Mandos plugin mandos-client: ");

1646

1958

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

1647

1959

exit(argp_err_exit_status);

1648

1960

break;

1673

1985

}

1674

1986

}

1675

1987

1676

if(getuid() == 0){

1988

{

1677

1989

/* Work around Debian bug #633582:

1678

1990

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

1679

struct stat st;

1680

1991

1681

1992

/* Re-raise priviliges */

1682

errno = 0;

1683

ret = seteuid(0);

1684

if(ret == -1){

1685

perror_plus("seteuid");

1686

}

1687

1688

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

1689

int seckey_fd = open(seckey, O_RDONLY);

1690

if(seckey_fd == -1){

1691

perror_plus("open");

1692

} else {

1693

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

1694

if(ret == -1){

1695

perror_plus("fstat");

1696

} else {

1697

if(S_ISREG(st.st_mode)

1698

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

1699

ret = fchown(seckey_fd, uid, gid);

1700

if(ret == -1){

1701

perror_plus("fchown");

1702

}

1703

}

1704

}

1705

TEMP_FAILURE_RETRY(close(seckey_fd));

1706

}

1707

}

1708

1709

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

1710

int pubkey_fd = open(pubkey, O_RDONLY);

1711

if(pubkey_fd == -1){

1712

perror_plus("open");

1713

} else {

1714

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

1715

if(ret == -1){

1716

perror_plus("fstat");

1717

} else {

1718

if(S_ISREG(st.st_mode)

1719

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

1720

ret = fchown(pubkey_fd, uid, gid);

1721

if(ret == -1){

1722

perror_plus("fchown");

1723

}

1724

}

1725

}

1726

TEMP_FAILURE_RETRY(close(pubkey_fd));

1727

}

1728

}

1729

1730

/* Lower privileges */

1731

errno = 0;

1732

ret = seteuid(uid);

1733

if(ret == -1){

1734

perror_plus("seteuid");

1993

if(raise_privileges() == 0){

1994

struct stat st;

1995

1996

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

1997

int seckey_fd = open(seckey, O_RDONLY);

1998

if(seckey_fd == -1){

1999

perror_plus("open");

2000

} else {

2001

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

2002

if(ret == -1){

2003

perror_plus("fstat");

2004

} else {

2005

if(S_ISREG(st.st_mode)

2006

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

2007

ret = fchown(seckey_fd, uid, gid);

2008

if(ret == -1){

2009

perror_plus("fchown");

2010

}

2011

}

2012

}

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2014

}

2015

}

2016

2017

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

2018

int pubkey_fd = open(pubkey, O_RDONLY);

2019

if(pubkey_fd == -1){

2020

perror_plus("open");

2021

} else {

2022

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

2023

if(ret == -1){

2024

perror_plus("fstat");

2025

} else {

2026

if(S_ISREG(st.st_mode)

2027

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

2028

ret = fchown(pubkey_fd, uid, gid);

2029

if(ret == -1){

2030

perror_plus("fchown");

2031

}

2032

}

2033

}

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2038

/* Lower privileges */

2039

lower_privileges();

2040

}

2041

}

2042

2043

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

2044

{

2045

char *interface = NULL;

2046

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

2047

interface))){

2048

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

2049

and if_nametoindex(interface) == 0){

2050

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

2051

fprintf_plus(stderr, "Not using nonexisting interface"

2052

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

2053

}

2054

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

2055

interface = NULL;

2056

}

1735

2057

}

1736

2058

}

1737

2059

1738

2060

/* Run network hooks */

1739

2061

{

1740

if(getuid() == 0){

1741

/* Re-raise priviliges */

1742

errno = 0;

1743

ret = seteuid(0);

1744

if(ret == -1){

1745

perror_plus("seteuid");

2062

if(mc.interfaces != NULL){

2063

interfaces_hooks = malloc(mc.interfaces_size);

2064

if(interfaces_hooks == NULL){

2065

perror_plus("malloc");

2066

goto end;

1746

2067

}

2068

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

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

1747

2072

}

1748

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

2073

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

2074

interfaces_hooks : "", delay)){

1749

2075

goto end;

1750

2076

}

1751

if(getuid() == 0){

1752

/* Lower privileges */

1753

errno = 0;

1754

ret = seteuid(uid);

1755

if(ret == -1){

1756

perror_plus("seteuid");

1757

}

1758

}

1759

2077

}

1760

2078

1761

2079

if(not debug){

1762

2080

avahi_set_log_function(empty_log);

1763

2081

}

1764

2082

1765

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

1766

struct dirent **direntries;

1767

/* First look for interfaces that are up */

1768

ret = scandir(sys_class_net, &direntries, up_interface,

1769

alphasort);

1770

if(ret == 0){

1771

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

1772

free(direntries);

1773

ret = scandir(sys_class_net, &direntries, good_interface,

1774

alphasort);

1775

}

1776

if(ret >= 1){

1777

/* Pick the first interface returned */

1778

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

1779

if(debug){

1780

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

1781

}

1782

if(interface == NULL){

1783

perror_plus("malloc");

1784

free(direntries);

1785

exitcode = EXIT_FAILURE;

1786

goto end;

1787

}

1788

free(direntries);

1789

} else {

1790

free(direntries);

1791

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

1792

exitcode = EXIT_FAILURE;

1793

goto end;

1794

}

1795

}

1796

1797

2083

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

1798

2084

from the signal handler */

1799

2085

/* Initialize the pseudo-RNG for Avahi */

1800

2086

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

1801

mc.simple_poll = avahi_simple_poll_new();

1802

if(mc.simple_poll == NULL){

2087

simple_poll = avahi_simple_poll_new();

2088

if(simple_poll == NULL){

1803

2089

fprintf_plus(stderr,

1804

2090

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

1805

2091

exitcode = EX_UNAVAILABLE;

1869

2155

}

1870

2156

}

1871

2157

1872

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

1873

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

1874

if_index = (AvahiIfIndex) if_nametoindex(interface);

1875

if(if_index == 0){

1876

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

1877

exitcode = EX_UNAVAILABLE;

1878

goto end;

1879

}

1880

1881

if(quit_now){

1882

goto end;

1883

}

1884

1885

/* Re-raise priviliges */

1886

errno = 0;

1887

ret = seteuid(0);

1888

if(ret == -1){

1889

perror_plus("seteuid");

1890

}

1891

1892

#ifdef __linux__

1893

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1894

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

1895

ret = klogctl(8, NULL, 5);

1896

bool restore_loglevel = true;

1897

if(ret == -1){

1898

restore_loglevel = false;

1899

perror_plus("klogctl");

1900

}

1901

#endif /* __linux__ */

1902

1903

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1904

if(sd < 0){

1905

perror_plus("socket");

1906

exitcode = EX_OSERR;

1907

#ifdef __linux__

1908

if(restore_loglevel){

1909

ret = klogctl(7, NULL, 0);

1910

if(ret == -1){

1911

perror_plus("klogctl");

1912

}

1913

}

1914

#endif /* __linux__ */

1915

/* Lower privileges */

1916

errno = 0;

1917

ret = seteuid(uid);

1918

if(ret == -1){

1919

perror_plus("seteuid");

1920

}

1921

goto end;

1922

}

1923

strcpy(network.ifr_name, interface);

1924

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

1925

if(ret == -1){

1926

perror_plus("ioctl SIOCGIFFLAGS");

1927

#ifdef __linux__

1928

if(restore_loglevel){

1929

ret = klogctl(7, NULL, 0);

1930

if(ret == -1){

1931

perror_plus("klogctl");

1932

}

1933

}

1934

#endif /* __linux__ */

1935

exitcode = EX_OSERR;

1936

/* Lower privileges */

1937

errno = 0;

1938

ret = seteuid(uid);

1939

if(ret == -1){

1940

perror_plus("seteuid");

1941

}

1942

goto end;

1943

}

1944

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

1945

network.ifr_flags |= IFF_UP;

1946

take_down_interface = true;

1947

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

1948

if(ret == -1){

1949

take_down_interface = false;

1950

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1951

exitcode = EX_OSERR;

1952

#ifdef __linux__

1953

if(restore_loglevel){

1954

ret = klogctl(7, NULL, 0);

1955

if(ret == -1){

1956

perror_plus("klogctl");

2158

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

2159

if(mc.interfaces == NULL){

2160

struct dirent **direntries;

2161

/* Look for any good interfaces */

2162

ret = scandir(sys_class_net, &direntries, good_interface,

2163

alphasort);

2164

if(ret >= 1){

2165

/* Add all found interfaces to interfaces list */

2166

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

2167

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

2168

direntries[i]->d_name);

2169

if(ret_errno != 0){

2170

perror_plus("argz_add");

2171

continue;

2172

}

2173

if(debug){

2174

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

2175

direntries[i]->d_name);

2176

}

2177

}

2178

free(direntries);

2179

} else {

2180

free(direntries);

2181

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

2182

exitcode = EXIT_FAILURE;

2183

goto end;

2184

}

2185

}

2186

2187

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

2188

{

2189

char *interface = NULL;

2190

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

2191

interface))){

2192

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

2193

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

2194

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

2195

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

2196

interface);

2197

interface = NULL;

2198

while((interface = argz_next(mc.interfaces,

2199

mc.interfaces_size, interface))){

2200

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

2201

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

2202

interface);

2203

interface = NULL;

1957

2204

}

1958

2205

}

1959

#endif /* __linux__ */

1960

/* Lower privileges */

1961

errno = 0;

1962

ret = seteuid(uid);

1963

if(ret == -1){

1964

perror_plus("seteuid");

1965

}

1966

goto end;

1967

}

1968

}

1969

/* Sleep checking until interface is running.

1970

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

1971

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

1972

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

1973

if(ret == -1){

1974

perror_plus("ioctl SIOCGIFFLAGS");

1975

} else if(network.ifr_flags & IFF_RUNNING){

1976

2206

break;

1977

2207

}

1978

struct timespec sleeptime = { .tv_nsec = 250000000 };

1979

ret = nanosleep(&sleeptime, NULL);

1980

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

1981

perror_plus("nanosleep");

1982

}

1983

}

1984

if(not take_down_interface){

1985

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

1986

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

1987

if(ret == -1){

1988

perror_plus("close");

1989

}

1990

}

1991

#ifdef __linux__

1992

if(restore_loglevel){

1993

/* Restores kernel loglevel to default */

1994

ret = klogctl(7, NULL, 0);

1995

if(ret == -1){

1996

perror_plus("klogctl");

1997

}

1998

}

1999

#endif /* __linux__ */

2000

/* Lower privileges */

2001

errno = 0;

2002

/* Lower privileges */

2003

ret = seteuid(uid);

2004

if(ret == -1){

2005

perror_plus("seteuid");

2006

}

2208

bool interface_was_up = interface_is_up(interface);

2209

ret = bring_up_interface(interface, delay);

2210

if(not interface_was_up){

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2214

} else {

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2218

}

2219

}

2220

}

2221

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

2222

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

2223

}

2224

}

2225

2226

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

2227

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

2228

if(debug){

2229

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

2230

mc.interfaces);

2231

}

2232

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

2007

2233

}

2008

2234

2009

2235

if(quit_now){

2010

2236

goto end;

2011

2237

}

2012

2238

2013

ret = init_gnutls_global(pubkey, seckey);

2239

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

2014

2240

if(ret == -1){

2015

2241

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

2016

2242

exitcode = EX_UNAVAILABLE;

2033

2259

goto end;

2034

2260

}

2035

2261

2036

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

2262

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

2037

2263

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

2038

2264

exitcode = EX_UNAVAILABLE;

2039

2265

goto end;

2049

2275

/* Connect directly, do not use Zeroconf */

2050

2276

/* (Mainly meant for debugging) */

2051

2277

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

2278

2052

2279

if(address == NULL){

2053

2280

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

2054

2281

exitcode = EX_USAGE;

2059

2286

goto end;

2060

2287

}

2061

2288

2062

uint16_t port;

2289

in_port_t port;

2063

2290

errno = 0;

2064

2291

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

2065

2292

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

2066

or tmpmax != (uint16_t)tmpmax){

2293

or tmpmax != (in_port_t)tmpmax){

2067

2294

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

2068

2295

exitcode = EX_USAGE;

2069

2296

goto end;

2070

2297

}

2071

2298

2072

2299

if(quit_now){

2073

2300

goto end;

2074

2301

}

2075

2302

2076

port = (uint16_t)tmpmax;

2303

port = (in_port_t)tmpmax;

2077

2304

*address = '\0';

2078

2305

/* Colon in address indicates IPv6 */

2079

2306

int af;

2095

2322

}

2096

2323

2097

2324

while(not quit_now){

2098

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

2325

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

2326

&mc);

2099

2327

if(quit_now or ret == 0){

2100

2328

break;

2101

2329

}

2127

2355

config.publish_domain = 0;

2128

2356

2129

2357

/* Allocate a new server */

2130

mc.server = avahi_server_new(avahi_simple_poll_get

2131

(mc.simple_poll), &config, NULL,

2132

NULL, &error);

2358

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2359

&config, NULL, NULL, &ret_errno);

2133

2360

2134

2361

/* Free the Avahi configuration data */

2135

2362

avahi_server_config_free(&config);

2138

2365

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

2139

2366

if(mc.server == NULL){

2140

2367

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

2141

avahi_strerror(error));

2368

avahi_strerror(ret_errno));

2142

2369

exitcode = EX_UNAVAILABLE;

2143

2370

goto end;

2144

2371

}

2150

2377

/* Create the Avahi service browser */

2151

2378

sb = avahi_s_service_browser_new(mc.server, if_index,

2152

2379

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2153

NULL, 0, browse_callback, NULL);

2380

NULL, 0, browse_callback,

2381

(void *)&mc);

2154

2382

if(sb == NULL){

2155

2383

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

2156

2384

avahi_strerror(avahi_server_errno(mc.server)));

2168

2396

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

2169

2397

}

2170

2398

2171

ret = avahi_loop_with_timeout(mc.simple_poll,

2172

(int)(retry_interval * 1000));

2399

ret = avahi_loop_with_timeout(simple_poll,

2400

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

2173

2401

if(debug){

2174

2402

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

2175

2403

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

2182

2410

}

2183

2411

2184

2412

/* Cleanup things */

2413

free(mc.interfaces);

2414

2185

2415

if(sb != NULL)

2186

2416

avahi_s_service_browser_free(sb);

2187

2417

2188

2418

if(mc.server != NULL)

2189

2419

avahi_server_free(mc.server);

2190

2420

2191

if(mc.simple_poll != NULL)

2192

avahi_simple_poll_free(mc.simple_poll);

2421

if(simple_poll != NULL)

2422

avahi_simple_poll_free(simple_poll);

2193

2423

2194

2424

if(gnutls_initialized){

2195

2425

gnutls_certificate_free_credentials(mc.cred);

2200

2430

if(gpgme_initialized){

2201

2431

gpgme_release(mc.ctx);

2202

2432

}

2203

2433

2204

2434

/* Cleans up the circular linked list of Mandos servers the client

2205

2435

has seen */

2206

2436

if(mc.current_server != NULL){

2214

2444

2215

2445

/* Re-raise priviliges */

2216

2446

{

2217

if(getuid() == 0){

2218

errno = 0;

2219

ret = seteuid(0);

2220

if(ret == -1){

2221

perror_plus("seteuid");

2222

}

2223

}

2447

raise_privileges();

2448

2224

2449

/* Run network hooks */

2225

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

2226

goto end;

2227

}

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2228

2452

2229

/* Take down the network interface */

2230

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

2231

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

2232

if(ret == -1){

2233

perror_plus("ioctl SIOCGIFFLAGS");

2234

} else if(network.ifr_flags & IFF_UP){

2235

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

2236

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

2237

if(ret == -1){

2238

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

2239

2463

}

2240

2464

}

2241

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

2242

if(ret == -1){

2243

perror_plus("close");

2465

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

2466

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

2467

" down\n");

2244

2468

}

2245

2469

}

2246

}

2247

if(getuid() == 0){

2248

/* Lower privileges permanently */

2249

errno = 0;

2250

ret = setuid(uid);

2251

if(ret == -1){

2252

perror_plus("setuid");

2253

}

2254

}

2470

2471

lower_privileges_permanently();

2472

}

2473

2474

free(interfaces_to_take_down);

2475

free(interfaces_hooks);

2255

2476

2256

2477

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

2257

2478

if(tempdir_created){