/mandos/release : revision 237.7.237

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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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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 */

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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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opendir(), DIR */

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

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

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inet_pton(), connect() */

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inet_pton(), connect(),

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getnameinfo() */

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

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

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

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

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

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

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

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

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

91

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92

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#ifdef __linux__

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99

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

135

141

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

136

142

char *connect_to = NULL;

137

143

const char *hookdir = HOOKDIR;

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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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uint16_t port;

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in_port_t port;

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AvahiIfIndex if_index;

144

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int af;

145

153

struct timespec last_seen;

149

157

150

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

151

159

typedef struct {

152

AvahiSimplePoll *simple_poll;

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160

AvahiServer *server;

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161

gnutls_certificate_credentials_t cred;

155

162

unsigned int dh_bits;

157

164

const char *priority;

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165

gpgme_ctx_t ctx;

159

166

server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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170

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

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

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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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173

168

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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183

perror(print_text);

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184

}

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185

180

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

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

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187

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

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188

va_list ap;

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va_start (ap, format);

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190

185

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

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192

program_invocation_short_name));

187

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

193

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

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}

189

195

190

196

/*

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198

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

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* "buffer_length" is how much is already used.

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200

*/

201

__attribute__((nonnull, warn_unused_result))

195

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

197

204

if(buffer_length + BUFFER_SIZE > buffer_capacity){

198

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

199

if(buffer == NULL){

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;

200

211

return 0;

201

212

}

213

*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

203

215

}

204

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return buffer_capacity;

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217

}

206

218

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

208

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

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int af){

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

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

212

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if(new_server == NULL){

221

234

perror_plus("strdup");

222

235

return false;

223

236

}

237

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

240

return false;

241

}

224

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/* Special case of first server */

225

if (mc.current_server == NULL){

243

if(*current_server == NULL){

226

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new_server->next = new_server;

227

245

new_server->prev = new_server;

228

mc.current_server = new_server;

229

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

246

*current_server = new_server;

230

247

} else {

231

new_server->next = mc.current_server;

232

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

248

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

249

new_server->next = *current_server;

250

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

233

251

new_server->prev->next = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

252

(*current_server)->prev = new_server;

240

253

}

241

254

return true;

242

255

}

244

257

/*

245

258

* Initialize GPGME.

246

259

*/

247

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

248

const char *tempdir){

260

__attribute__((nonnull, warn_unused_result))

261

static bool init_gpgme(const char * const seckey,

262

const char * const pubkey,

263

const char * const tempdir,

264

mandos_context *mc){

249

265

gpgme_error_t rc;

250

266

gpgme_engine_info_t engine_info;

251

267

252

253

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/*

254

269

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

255

270

*/

256

bool import_key(const char *filename){

271

bool import_key(const char * const filename){

257

272

int ret;

258

273

int fd;

259

274

gpgme_data_t pgp_data;

271

286

return false;

272

287

}

273

288

274

rc = gpgme_op_import(mc.ctx, pgp_data);

289

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

275

290

if(rc != GPG_ERR_NO_ERROR){

276

291

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

277

292

gpgme_strsource(rc), gpgme_strerror(rc));

321

336

}

322

337

323

338

/* Create new GPGME "context" */

324

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

339

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

325

340

if(rc != GPG_ERR_NO_ERROR){

326

341

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

327

342

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

340

355

* Decrypt OpenPGP data.

341

356

* Returns -1 on error

342

357

*/

358

__attribute__((nonnull, warn_unused_result))

343

359

static ssize_t pgp_packet_decrypt(const char *cryptotext,

344

360

size_t crypto_size,

345

char **plaintext){

361

char **plaintext,

362

mandos_context *mc){

346

363

gpgme_data_t dh_crypto, dh_plain;

347

364

gpgme_error_t rc;

348

365

ssize_t ret;

374

391

375

392

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

376

393

data buffer */

377

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

394

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

378

395

if(rc != GPG_ERR_NO_ERROR){

379

396

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

380

397

gpgme_strsource(rc), gpgme_strerror(rc));

381

398

plaintext_length = -1;

382

399

if(debug){

383

400

gpgme_decrypt_result_t result;

384

result = gpgme_op_decrypt_result(mc.ctx);

401

result = gpgme_op_decrypt_result(mc->ctx);

385

402

if(result == NULL){

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403

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

387

404

} else {

464

481

return plaintext_length;

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482

}

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483

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

484

__attribute__((warn_unused_result))

485

static const char *safer_gnutls_strerror(int value){

486

const char *ret = gnutls_strerror(value);

470

487

if(ret == NULL)

471

488

ret = "(unknown)";

472

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return ret;

473

490

}

474

491

475

492

/* GnuTLS log function callback */

493

__attribute__((nonnull))

476

494

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

477

495

const char* string){

478

496

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

479

497

}

480

498

499

__attribute__((nonnull, warn_unused_result))

481

500

static int init_gnutls_global(const char *pubkeyfilename,

482

const char *seckeyfilename){

501

const char *seckeyfilename,

502

mandos_context *mc){

483

503

int ret;

484

504

485

505

if(debug){

502

522

}

503

523

504

524

/* OpenPGP credentials */

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

525

ret = gnutls_certificate_allocate_credentials(&mc->cred);

506

526

if(ret != GNUTLS_E_SUCCESS){

507

527

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

508

528

safer_gnutls_strerror(ret));

518

538

}

519

539

520

540

ret = gnutls_certificate_set_openpgp_key_file

521

(mc.cred, pubkeyfilename, seckeyfilename,

541

(mc->cred, pubkeyfilename, seckeyfilename,

522

542

GNUTLS_OPENPGP_FMT_BASE64);

523

543

if(ret != GNUTLS_E_SUCCESS){

524

544

fprintf_plus(stderr,

530

550

}

531

551

532

552

/* GnuTLS server initialization */

533

ret = gnutls_dh_params_init(&mc.dh_params);

553

ret = gnutls_dh_params_init(&mc->dh_params);

534

554

if(ret != GNUTLS_E_SUCCESS){

535

555

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

536

556

" initialization: %s\n",

537

557

safer_gnutls_strerror(ret));

538

558

goto globalfail;

539

559

}

540

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

560

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

541

561

if(ret != GNUTLS_E_SUCCESS){

542

562

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

543

563

safer_gnutls_strerror(ret));

544

564

goto globalfail;

545

565

}

546

566

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

567

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

548

568

549

569

return 0;

550

570

551

571

globalfail:

552

572

553

gnutls_certificate_free_credentials(mc.cred);

573

gnutls_certificate_free_credentials(mc->cred);

554

574

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

575

gnutls_dh_params_deinit(mc->dh_params);

556

576

return -1;

557

577

}

558

578

559

static int init_gnutls_session(gnutls_session_t *session){

579

__attribute__((nonnull, warn_unused_result))

580

static int init_gnutls_session(gnutls_session_t *session,

581

mandos_context *mc){

560

582

int ret;

561

583

/* GnuTLS session creation */

562

584

do {

574

596

{

575

597

const char *err;

576

598

do {

577

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

599

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

578

600

if(quit_now){

579

601

gnutls_deinit(*session);

580

602

return -1;

591

613

592

614

do {

593

615

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

594

mc.cred);

616

mc->cred);

595

617

if(quit_now){

596

618

gnutls_deinit(*session);

597

619

return -1;

607

629

/* ignore client certificate if any. */

608

630

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

609

631

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

611

633

612

634

return 0;

613

635

}

617

639

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

618

640

619

641

/* Called when a Mandos server is found */

620

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

642

__attribute__((nonnull, warn_unused_result))

643

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

621

644

AvahiIfIndex if_index,

622

int af){

645

int af, mandos_context *mc){

623

646

int ret, tcp_sd = -1;

624

647

ssize_t sret;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

648

struct sockaddr_storage to;

629

649

char *buffer = NULL;

630

650

char *decrypted_buffer = NULL;

631

651

size_t buffer_length = 0;

655

675

return -1;

656

676

}

657

677

658

ret = init_gnutls_session(&session);

678

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

679

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

680

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

681

bool match = false;

682

{

683

char *interface = NULL;

684

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

685

interface))){

686

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

687

match = true;

688

break;

689

}

690

}

691

}

692

if(not match){

693

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

694

connect to the server */

695

if(debug){

696

char interface[IF_NAMESIZE];

697

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

698

perror_plus("if_indextoname");

699

} else {

700

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

701

" \"%s\"\n",

702

if_indextoname((unsigned int)if_index,

703

interface));

704

}

705

}

706

return -1;

707

}

708

}

709

710

ret = init_gnutls_session(&session, mc);

659

711

if(ret != 0){

660

712

return -1;

661

713

}

662

714

663

715

if(debug){

664

716

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

665

PRIu16 "\n", ip, port);

717

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

666

718

}

667

719

668

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

680

732

681

733

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

682

734

if(af == AF_INET6){

683

to.in6.sin6_family = (sa_family_t)af;

684

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

735

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

736

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

685

737

} else { /* IPv4 */

686

to.in.sin_family = (sa_family_t)af;

687

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

738

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

739

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

688

740

}

689

741

if(ret < 0 ){

690

742

int e = errno;

699

751

goto mandos_end;

700

752

}

701

753

if(af == AF_INET6){

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

754

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

755

if(IN6_IS_ADDR_LINKLOCAL

756

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

709

757

if(if_index == AVAHI_IF_UNSPEC){

710

758

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

711

759

" incomplete without a network interface\n");

713

761

goto mandos_end;

714

762

}

715

763

/* Set the network interface number as scope */

716

to.in6.sin6_scope_id = (uint32_t)if_index;

764

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

717

765

}

718

766

} else {

719

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

720

-Wconversion and

721

-Wunreachable-code */

767

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

722

768

}

723

769

724

770

if(quit_now){

732

778

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

733

779

perror_plus("if_indextoname");

734

780

} else {

735

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

736

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

781

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

782

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

737

783

}

738

784

} else {

739

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

740

ip, port);

785

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

786

ip, (uintmax_t)port);

741

787

}

742

788

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

743

789

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

744

const char *pcret;

745

790

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

791

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

792

sizeof(struct sockaddr_in6),

793

addrstr, sizeof(addrstr), NULL, 0,

794

NI_NUMERICHOST);

748

795

} else {

749

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

750

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

751

800

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

801

if(ret == EAI_SYSTEM){

802

perror_plus("getnameinfo");

803

} else if(ret != 0) {

804

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

805

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

806

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

758

807

}

759

808

}

760

809

764

813

}

765

814

766

815

if(af == AF_INET6){

767

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

816

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

817

sizeof(struct sockaddr_in6));

768

818

} else {

769

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

819

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

820

sizeof(struct sockaddr_in));

770

821

}

771

822

if(ret < 0){

772

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

823

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

773

824

int e = errno;

774

825

perror_plus("connect");

775

826

errno = e;

821

872

goto mandos_end;

822

873

}

823

874

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

875

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

876

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

877

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

878

gnutls_transport_set_ptr(session,

879

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

826

880

827

881

if(quit_now){

828

882

errno = EINTR;

933

987

if(buffer_length > 0){

934

988

ssize_t decrypted_buffer_size;

935

989

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

936

&decrypted_buffer);

990

&decrypted_buffer, mc);

937

991

if(decrypted_buffer_size >= 0){

938

992

939

993

written = 0;

987

1041

return retval;

988

1042

}

989

1043

1044

__attribute__((nonnull))

990

1045

static void resolve_callback(AvahiSServiceResolver *r,

991

1046

AvahiIfIndex interface,

992

1047

AvahiProtocol proto,

1000

1055

AVAHI_GCC_UNUSED AvahiStringList *txt,

1001

1056

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1002

1057

flags,

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1058

void *mc){

1059

if(r == NULL){

1060

return;

1061

}

1005

1062

1006

1063

/* Called whenever a service has been resolved successfully or

1007

1064

timed out */

1016

1073

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

1017

1074

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

1018

1075

domain,

1019

avahi_strerror(avahi_server_errno(mc.server)));

1076

avahi_strerror(avahi_server_errno

1077

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

1020

1078

break;

1021

1079

1022

1080

case AVAHI_RESOLVER_FOUND:

1028

1086

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

1029

1087

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

1030

1088

}

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1089

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

1090

interface,

1091

avahi_proto_to_af(proto),

1092

mc);

1033

1093

if(ret == 0){

1034

avahi_simple_poll_quit(mc.simple_poll);

1094

avahi_simple_poll_quit(simple_poll);

1035

1095

} else {

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1096

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

1097

avahi_proto_to_af(proto),

1098

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

1038

1099

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

1039

1100

" list\n", name);

1040

1101

}

1053

1114

const char *domain,

1054

1115

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1055

1116

flags,

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1117

void *mc){

1118

if(b == NULL){

1119

return;

1120

}

1058

1121

1059

1122

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

1060

1123

is removed from the LAN */

1068

1131

case AVAHI_BROWSER_FAILURE:

1069

1132

1070

1133

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

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1134

avahi_strerror(avahi_server_errno

1135

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

1136

avahi_simple_poll_quit(simple_poll);

1073

1137

return;

1074

1138

1075

1139

case AVAHI_BROWSER_NEW:

1078

1142

the callback function is called the Avahi server will free the

1079

1143

resolver for us. */

1080

1144

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1145

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

1146

interface, protocol, name, type,

1147

domain, protocol, 0,

1148

resolve_callback, mc) == NULL)

1084

1149

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

1085

1150

" %s\n", name,

1086

avahi_strerror(avahi_server_errno(mc.server)));

1151

avahi_strerror(avahi_server_errno

1152

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

1087

1153

break;

1088

1154

1089

1155

case AVAHI_BROWSER_REMOVE:

1108

1174

signal_received = sig;

1109

1175

int old_errno = errno;

1110

1176

/* set main loop to exit */

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1177

if(simple_poll != NULL){

1178

avahi_simple_poll_quit(simple_poll);

1113

1179

}

1114

1180

errno = old_errno;

1115

1181

}

1116

1182

1183

__attribute__((nonnull, warn_unused_result))

1117

1184

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

1118

1185

int ret;

1186

error_t ret_errno;

1119

1187

1120

1188

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

1121

1189

if(s < 0){

1190

ret_errno = errno;

1122

1191

perror_plus("socket");

1192

errno = ret_errno;

1123

1193

return false;

1124

1194

}

1125

1195

strcpy(ifr->ifr_name, ifname);

1126

1196

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1127

1197

if(ret == -1){

1128

1198

if(debug){

1199

ret_errno = errno;

1129

1200

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1130

1202

}

1131

1203

return false;

1132

1204

}

1133

1205

return true;

1134

1206

}

1135

1207

1208

__attribute__((nonnull, warn_unused_result))

1136

1209

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

1137

1210

1138

1211

/* Reject the loopback device */

1180

1253

* corresponds to an acceptable network device.

1181

1254

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

1182

1255

*/

1256

__attribute__((nonnull, warn_unused_result))

1183

1257

int good_interface(const struct dirent *if_entry){

1184

1258

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

1185

1259

return 0;

1201

1275

}

1202

1276

1203

1277

/*

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1278

* This function determines if a network interface is up.

1279

*/

1280

__attribute__((nonnull, warn_unused_result))

1281

bool interface_is_up(const char *interface){

1282

struct ifreq ifr;

1283

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

1284

if(debug){

1285

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

1286

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

1287

}

1288

return false;

1289

}

1290

1291

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

1292

}

1293

1294

/*

1295

* This function determines if a network interface is running

1296

*/

1297

__attribute__((nonnull, warn_unused_result))

1298

bool interface_is_running(const char *interface){

1299

struct ifreq ifr;

1300

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

1301

if(debug){

1302

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

1303

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

1304

}

1305

return false;

1306

}

1307

1308

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

1309

}

1310

1311

__attribute__((nonnull, pure, warn_unused_result))

1246

1312

int notdotentries(const struct dirent *direntry){

1247

1313

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

1248

1314

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

1255

1321

}

1256

1322

1257

1323

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

1324

__attribute__((nonnull, warn_unused_result))

1258

1325

int runnable_hook(const struct dirent *direntry){

1259

1326

int ret;

1260

1327

size_t sret;

1268

1335

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

1269

1336

"abcdefghijklmnopqrstuvwxyz"

1270

1337

"0123456789"

1271

"_-");

1338

"_.-");

1272

1339

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

1273

1340

/* Contains non-allowed characters */

1274

1341

if(debug){

1292

1359

}

1293

1360

return 0;

1294

1361

}

1362

free(fullname);

1295

1363

if(not (S_ISREG(st.st_mode))){

1296

1364

/* Not a regular file */

1297

1365

if(debug){

1315

1383

return 1;

1316

1384

}

1317

1385

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1386

__attribute__((nonnull, warn_unused_result))

1387

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1388

mandos_context *mc){

1319

1389

int ret;

1320

1390

struct timespec now;

1321

1391

struct timespec waited_time;

1322

1392

intmax_t block_time;

1323

1393

1324

1394

while(true){

1325

if(mc.current_server == NULL){

1326

if (debug){

1395

if(mc->current_server == NULL){

1396

if(debug){

1327

1397

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

1328

1398

" No timeout!\n");

1329

1399

}

1330

1400

ret = avahi_simple_poll_iterate(s, -1);

1331

1401

} else {

1332

if (debug){

1402

if(debug){

1333

1403

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

1334

1404

" it, or wait\n");

1335

1405

}

1342

1412

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

1343

1413

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

1344

1414

waited_time.tv_sec = (now.tv_sec

1345

- mc.current_server->last_seen.tv_sec);

1415

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

1346

1416

waited_time.tv_nsec = (now.tv_nsec

1347

- mc.current_server->last_seen.tv_nsec);

1417

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

1348

1418

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

1349

1419

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

1350

1420

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

1352

1422

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

1353

1423

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

1354

1424

1355

if (debug){

1425

if(debug){

1356

1426

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

1357

1427

block_time);

1358

1428

}

1359

1429

1360

1430

if(block_time <= 0){

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

1431

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

1432

mc->current_server->port,

1433

mc->current_server->if_index,

1434

mc->current_server->af, mc);

1365

1435

if(ret == 0){

1366

avahi_simple_poll_quit(mc.simple_poll);

1436

avahi_simple_poll_quit(s);

1367

1437

return 0;

1368

1438

}

1369

1439

ret = clock_gettime(CLOCK_MONOTONIC,

1370

&mc.current_server->last_seen);

1440

&mc->current_server->last_seen);

1371

1441

if(ret == -1){

1372

1442

perror_plus("clock_gettime");

1373

1443

return -1;

1374

1444

}

1375

mc.current_server = mc.current_server->next;

1445

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

1376

1446

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

1377

1447

servers, but don't block */

1378

1448

}

1380

1450

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

1381

1451

}

1382

1452

if(ret != 0){

1383

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

1453

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

1384

1454

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

1385

1455

}

1386

1456

}

1387

1457

}

1388

1458

}

1389

1459

1390

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

1460

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

1461

__attribute__((warn_unused_result))

1462

error_t raise_privileges(void){

1463

error_t old_errno = errno;

1464

error_t ret_errno = 0;

1465

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

1466

ret_errno = errno;

1467

perror_plus("seteuid");

1468

}

1469

errno = old_errno;

1470

return ret_errno;

1471

}

1472

1473

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

1474

__attribute__((warn_unused_result))

1475

error_t raise_privileges_permanently(void){

1476

error_t old_errno = errno;

1477

error_t ret_errno = raise_privileges();

1478

if(ret_errno != 0){

1479

errno = old_errno;

1480

return ret_errno;

1481

}

1482

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

1483

ret_errno = errno;

1484

perror_plus("seteuid");

1485

}

1486

errno = old_errno;

1487

return ret_errno;

1488

}

1489

1490

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

1491

__attribute__((warn_unused_result))

1492

error_t lower_privileges(void){

1493

error_t old_errno = errno;

1494

error_t ret_errno = 0;

1495

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

1496

ret_errno = errno;

1497

perror_plus("seteuid");

1498

}

1499

errno = old_errno;

1500

return ret_errno;

1501

}

1502

1503

/* Lower privileges permanently */

1504

__attribute__((warn_unused_result))

1505

error_t lower_privileges_permanently(void){

1506

error_t old_errno = errno;

1507

error_t ret_errno = 0;

1508

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

1509

ret_errno = errno;

1510

perror_plus("setuid");

1511

}

1512

errno = old_errno;

1513

return ret_errno;

1514

}

1515

1516

__attribute__((nonnull))

1517

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

1391

1518

const float delay){

1392

1519

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

1520

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

1396

1521

alphasort);

1397

1522

if(numhooks == -1){

1398

perror_plus("scandir");

1523

if(errno == ENOENT){

1524

if(debug){

1525

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

1526

" found\n", hookdir);

1527

}

1528

} else {

1529

perror_plus("scandir");

1530

}

1399

1531

} else {

1532

struct dirent *direntry;

1533

int ret;

1400

1534

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

1401

1535

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

1402

1536

direntry = direntries[i];

1414

1548

if(hook_pid == 0){

1415

1549

/* Child */

1416

1550

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1551

if(raise_privileges_permanently() != 0){

1552

perror_plus("Failed to raise privileges");

1553

_exit(EX_NOPERM);

1427

1554

}

1428

1555

/* Set group */

1429

1556

errno = 0;

1430

1557

ret = setgid(0);

1431

1558

if(ret == -1){

1432

1559

perror_plus("setgid");

1560

_exit(EX_NOPERM);

1433

1561

}

1434

1562

/* Reset supplementary groups */

1435

1563

errno = 0;

1436

1564

ret = setgroups(0, NULL);

1437

1565

if(ret == -1){

1438

1566

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1567

_exit(EX_NOPERM);

1568

}

1569

ret = dup2(devnull, STDIN_FILENO);

1570

if(ret == -1){

1571

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

1572

_exit(EX_OSERR);

1573

}

1574

ret = close(devnull);

1575

if(ret == -1){

1576

perror_plus("close");

1577

_exit(EX_OSERR);

1578

}

1579

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1580

if(ret == -1){

1581

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

1582

_exit(EX_OSERR);

1583

}

1443

1584

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

1444

1585

if(ret == -1){

1445

1586

perror_plus("setenv");

1461

1602

_exit(EX_OSERR);

1462

1603

}

1463

1604

char *delaystring;

1464

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

1605

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

1465

1606

if(ret == -1){

1466

1607

perror_plus("asprintf");

1467

1608

_exit(EX_OSERR);

1520

1661

}

1521

1662

close(devnull);

1522

1663

}

1523

return true;

1664

}

1665

1666

__attribute__((nonnull, warn_unused_result))

1667

error_t bring_up_interface(const char *const interface,

1668

const float delay){

1669

error_t old_errno = errno;

1670

int ret;

1671

struct ifreq network;

1672

unsigned int if_index = if_nametoindex(interface);

1673

if(if_index == 0){

1674

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

1675

errno = old_errno;

1676

return ENXIO;

1677

}

1678

1679

if(quit_now){

1680

errno = old_errno;

1681

return EINTR;

1682

}

1683

1684

if(not interface_is_up(interface)){

1685

error_t ret_errno = 0, ioctl_errno = 0;

1686

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

1687

ret_errno = errno;

1688

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

1689

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

1690

errno = old_errno;

1691

return ret_errno;

1692

}

1693

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

1694

1695

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

1696

if(sd == -1){

1697

ret_errno = errno;

1698

perror_plus("socket");

1699

errno = old_errno;

1700

return ret_errno;

1701

}

1702

1703

if(quit_now){

1704

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

1705

if(ret == -1){

1706

perror_plus("close");

1707

}

1708

errno = old_errno;

1709

return EINTR;

1710

}

1711

1712

if(debug){

1713

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

1714

interface);

1715

}

1716

1717

/* Raise privileges */

1718

ret_errno = raise_privileges();

1719

if(ret_errno != 0){

1720

perror_plus("Failed to raise privileges");

1721

}

1722

1723

#ifdef __linux__

1724

int ret_linux;

1725

bool restore_loglevel = false;

1726

if(ret_errno == 0){

1727

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1728

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

1729

ret_linux = klogctl(8, NULL, 5);

1730

if(ret_linux == -1){

1731

perror_plus("klogctl");

1732

} else {

1733

restore_loglevel = true;

1734

}

1735

}

1736

#endif /* __linux__ */

1737

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

1738

ioctl_errno = errno;

1739

#ifdef __linux__

1740

if(restore_loglevel){

1741

ret_linux = klogctl(7, NULL, 0);

1742

if(ret_linux == -1){

1743

perror_plus("klogctl");

1744

}

1745

}

1746

#endif /* __linux__ */

1747

1748

/* If raise_privileges() succeeded above */

1749

if(ret_errno == 0){

1750

/* Lower privileges */

1751

ret_errno = lower_privileges();

1752

if(ret_errno != 0){

1753

errno = ret_errno;

1754

perror_plus("Failed to lower privileges");

1755

}

1756

}

1757

1758

/* Close the socket */

1759

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

1760

if(ret == -1){

1761

perror_plus("close");

1762

}

1763

1764

if(ret_setflags == -1){

1765

errno = ioctl_errno;

1766

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1767

errno = old_errno;

1768

return ioctl_errno;

1769

}

1770

} else if(debug){

1771

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

1772

interface);

1773

}

1774

1775

/* Sleep checking until interface is running.

1776

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

1777

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

1778

if(interface_is_running(interface)){

1779

break;

1780

}

1781

struct timespec sleeptime = { .tv_nsec = 250000000 };

1782

ret = nanosleep(&sleeptime, NULL);

1783

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

1784

perror_plus("nanosleep");

1785

}

1786

}

1787

1788

errno = old_errno;

1789

return 0;

1790

}

1791

1792

__attribute__((nonnull, warn_unused_result))

1793

error_t take_down_interface(const char *const interface){

1794

error_t old_errno = errno;

1795

struct ifreq network;

1796

unsigned int if_index = if_nametoindex(interface);

1797

if(if_index == 0){

1798

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

1799

errno = old_errno;

1800

return ENXIO;

1801

}

1802

if(interface_is_up(interface)){

1803

error_t ret_errno = 0, ioctl_errno = 0;

1804

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

1805

ret_errno = errno;

1806

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

1807

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

1808

errno = old_errno;

1809

return ret_errno;

1810

}

1811

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

1812

1813

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

1814

if(sd == -1){

1815

ret_errno = errno;

1816

perror_plus("socket");

1817

errno = old_errno;

1818

return ret_errno;

1819

}

1820

1821

if(debug){

1822

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

1823

interface);

1824

}

1825

1826

/* Raise privileges */

1827

ret_errno = raise_privileges();

1828

if(ret_errno != 0){

1829

perror_plus("Failed to raise privileges");

1830

}

1831

1832

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

1833

ioctl_errno = errno;

1834

1835

/* If raise_privileges() succeeded above */

1836

if(ret_errno == 0){

1837

/* Lower privileges */

1838

ret_errno = lower_privileges();

1839

if(ret_errno != 0){

1840

errno = ret_errno;

1841

perror_plus("Failed to lower privileges");

1842

}

1843

}

1844

1845

/* Close the socket */

1846

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

1847

if(ret == -1){

1848

perror_plus("close");

1849

}

1850

1851

if(ret_setflags == -1){

1852

errno = ioctl_errno;

1853

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1854

errno = old_errno;

1855

return ioctl_errno;

1856

}

1857

} else if(debug){

1858

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

1859

interface);

1860

}

1861

1862

errno = old_errno;

1863

return 0;

1524

1864

}

1525

1865

1526

1866

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

1867

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

1868

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

1869

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

1870

.interfaces = NULL, .interfaces_size = 0 };

1527

1871

AvahiSServiceBrowser *sb = NULL;

1528

int error;

1872

error_t ret_errno;

1529

1873

int ret;

1530

1874

intmax_t tmpmax;

1531

1875

char *tmp;

1532

1876

int exitcode = EXIT_SUCCESS;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1539

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

1540

bool tempdir_created = false;

1877

char *interfaces_to_take_down = NULL;

1878

size_t interfaces_to_take_down_size = 0;

1879

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

1880

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

1881

char *tempdir = NULL;

1541

1882

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1542

1883

const char *seckey = PATHDIR "/" SECKEY;

1543

1884

const char *pubkey = PATHDIR "/" PUBKEY;

1885

char *interfaces_hooks = NULL;

1544

1886

1545

1887

bool gnutls_initialized = false;

1546

1888

bool gpgme_initialized = false;

1637

1979

connect_to = arg;

1638

1980

break;

1639

1981

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

1640

interface = arg;

1982

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

1983

arg, (int)',');

1984

if(ret_errno != 0){

1985

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

1986

}

1641

1987

break;

1642

1988

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

1643

1989

seckey = arg;

1720

2066

/* Work around Debian bug #633582:

1721

2067

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

1722

2068

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

2069

/* Re-raise privileges */

2070

ret_errno = raise_privileges();

2071

if(ret_errno != 0){

2072

errno = ret_errno;

2073

perror_plus("Failed to raise privileges");

1728

2074

} else {

1729

2075

struct stat st;

1730

2076

1771

2117

}

1772

2118

1773

2119

/* Lower privileges */

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

2120

ret_errno = lower_privileges();

2121

if(ret_errno != 0){

2122

errno = ret_errno;

2123

perror_plus("Failed to lower privileges");

2124

}

2125

}

2126

}

2127

2128

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

2129

{

2130

char *interface = NULL;

2131

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

2132

interface))){

2133

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

2134

and if_nametoindex(interface) == 0){

2135

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

2136

fprintf_plus(stderr, "Not using nonexisting interface"

2137

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

2138

}

2139

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

2140

interface = NULL;

1778

2141

}

1779

2142

}

1780

2143

}

1781

2144

1782

2145

/* Run network hooks */

1783

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

1784

goto end;

2146

{

2147

if(mc.interfaces != NULL){

2148

interfaces_hooks = malloc(mc.interfaces_size);

2149

if(interfaces_hooks == NULL){

2150

perror_plus("malloc");

2151

goto end;

2152

}

2153

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

2154

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

2155

}

2156

run_network_hooks("start", interfaces_hooks != NULL ?

2157

interfaces_hooks : "", delay);

1785

2158

}

1786

2159

1787

2160

if(not debug){

1788

2161

avahi_set_log_function(empty_log);

1789

2162

}

1790

2163

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

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

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

1823

2164

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

1824

2165

from the signal handler */

1825

2166

/* Initialize the pseudo-RNG for Avahi */

1826

2167

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

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2168

simple_poll = avahi_simple_poll_new();

2169

if(simple_poll == NULL){

1829

2170

fprintf_plus(stderr,

1830

2171

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

1831

2172

exitcode = EX_UNAVAILABLE;

1895

2236

}

1896

2237

}

1897

2238

1898

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

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

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

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

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

2239

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

2240

if(mc.interfaces == NULL){

2241

struct dirent **direntries;

2242

/* Look for any good interfaces */

2243

ret = scandir(sys_class_net, &direntries, good_interface,

2244

alphasort);

2245

if(ret >= 1){

2246

/* Add all found interfaces to interfaces list */

2247

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

2248

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

2249

direntries[i]->d_name);

2250

if(ret_errno != 0){

2251

errno = ret_errno;

2252

perror_plus("argz_add");

2253

continue;

2254

}

2255

if(debug){

2256

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

2257

direntries[i]->d_name);

2258

}

2259

}

2260

free(direntries);

2261

} else {

2262

free(direntries);

2263

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

2264

exitcode = EXIT_FAILURE;

2265

goto end;

2266

}

2267

}

2268

2269

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

2270

{

2271

char *interface = NULL;

2272

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

2273

interface))){

2274

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

2275

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

2276

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

2277

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

2278

interface);

2279

interface = NULL;

2280

while((interface = argz_next(mc.interfaces,

2281

mc.interfaces_size, interface))){

2282

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

2283

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

2284

interface);

2285

interface = NULL;

1983

2286

}

1984

2287

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

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

1997

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

1998

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

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2002

2288

break;

2003

2289

}

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2290

bool interface_was_up = interface_is_up(interface);

2291

errno = bring_up_interface(interface, delay);

2292

if(not interface_was_up){

2293

if(errno != 0){

2294

perror_plus("Failed to bring up interface");

2295

} else {

2296

errno = argz_add(&interfaces_to_take_down,

2297

&interfaces_to_take_down_size,

2298

interface);

2299

if(errno != 0){

2300

perror_plus("argz_add");

2301

}

2302

}

2303

}

2304

}

2305

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

2306

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

2307

}

2308

}

2309

2310

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

2311

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

2312

if(debug){

2313

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

2314

mc.interfaces);

2315

}

2316

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

2033

2317

}

2034

2318

2035

2319

if(quit_now){

2036

2320

goto end;

2037

2321

}

2038

2322

2039

ret = init_gnutls_global(pubkey, seckey);

2323

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

2040

2324

if(ret == -1){

2041

2325

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

2042

2326

exitcode = EX_UNAVAILABLE;

2049

2333

goto end;

2050

2334

}

2051

2335

2052

if(mkdtemp(tempdir) == NULL){

2336

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

2337

tempdir = mkdtemp(run_tempdir);

2338

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

2339

if(debug){

2340

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

2341

run_tempdir, old_tempdir);

2342

}

2343

tempdir = mkdtemp(old_tempdir);

2344

}

2345

if(tempdir == NULL){

2053

2346

perror_plus("mkdtemp");

2054

2347

goto end;

2055

2348

}

2056

tempdir_created = true;

2057

2349

2058

2350

if(quit_now){

2059

2351

goto end;

2060

2352

}

2061

2353

2062

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

2354

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

2063

2355

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

2064

2356

exitcode = EX_UNAVAILABLE;

2065

2357

goto end;

2075

2367

/* Connect directly, do not use Zeroconf */

2076

2368

/* (Mainly meant for debugging) */

2077

2369

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

2370

2078

2371

if(address == NULL){

2079

2372

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

2080

2373

exitcode = EX_USAGE;

2085

2378

goto end;

2086

2379

}

2087

2380

2088

uint16_t port;

2381

in_port_t port;

2089

2382

errno = 0;

2090

2383

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

2091

2384

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

2092

or tmpmax != (uint16_t)tmpmax){

2385

or tmpmax != (in_port_t)tmpmax){

2093

2386

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

2094

2387

exitcode = EX_USAGE;

2095

2388

goto end;

2096

2389

}

2097

2390

2098

2391

if(quit_now){

2099

2392

goto end;

2100

2393

}

2101

2394

2102

port = (uint16_t)tmpmax;

2395

port = (in_port_t)tmpmax;

2103

2396

*address = '\0';

2104

2397

/* Colon in address indicates IPv6 */

2105

2398

int af;

2121

2414

}

2122

2415

2123

2416

while(not quit_now){

2124

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

2417

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

2418

&mc);

2125

2419

if(quit_now or ret == 0){

2126

2420

break;

2127

2421

}

2129

2423

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

2130

2424

(int)retry_interval);

2131

2425

}

2132

sleep((int)retry_interval);

2426

sleep((unsigned int)retry_interval);

2133

2427

}

2134

2428

2135

if (not quit_now){

2429

if(not quit_now){

2136

2430

exitcode = EXIT_SUCCESS;

2137

2431

}

2138

2432

2153

2447

config.publish_domain = 0;

2154

2448

2155

2449

/* Allocate a new server */

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

2450

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2451

&config, NULL, NULL, &ret_errno);

2159

2452

2160

2453

/* Free the Avahi configuration data */

2161

2454

avahi_server_config_free(&config);

2164

2457

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

2165

2458

if(mc.server == NULL){

2166

2459

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

2167

avahi_strerror(error));

2460

avahi_strerror(ret_errno));

2168

2461

exitcode = EX_UNAVAILABLE;

2169

2462

goto end;

2170

2463

}

2176

2469

/* Create the Avahi service browser */

2177

2470

sb = avahi_s_service_browser_new(mc.server, if_index,

2178

2471

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2179

NULL, 0, browse_callback, NULL);

2472

NULL, 0, browse_callback,

2473

(void *)&mc);

2180

2474

if(sb == NULL){

2181

2475

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

2182

2476

avahi_strerror(avahi_server_errno(mc.server)));

2193

2487

if(debug){

2194

2488

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

2195

2489

}

2196

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

2490

2491

ret = avahi_loop_with_timeout(simple_poll,

2492

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

2199

2493

if(debug){

2200

2494

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

2201

2495

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

2208

2502

}

2209

2503

2210

2504

/* Cleanup things */

2505

free(mc.interfaces);

2506

2211

2507

if(sb != NULL)

2212

2508

avahi_s_service_browser_free(sb);

2213

2509

2214

2510

if(mc.server != NULL)

2215

2511

avahi_server_free(mc.server);

2216

2512

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

2513

if(simple_poll != NULL)

2514

avahi_simple_poll_free(simple_poll);

2219

2515

2220

2516

if(gnutls_initialized){

2221

2517

gnutls_certificate_free_credentials(mc.cred);

2238

2534

}

2239

2535

}

2240

2536

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

2537

/* Re-raise privileges */

2245

2538

{

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

2539

ret_errno = raise_privileges();

2540

if(ret_errno != 0){

2541

perror_plus("Failed to raise privileges");

2542

} else {

2543

2544

/* Run network hooks */

2545

run_network_hooks("stop", interfaces_hooks != NULL ?

2546

interfaces_hooks : "", delay);

2547

2548

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

2549

{

2550

char *interface = NULL;

2551

while((interface=argz_next(interfaces_to_take_down,

2552

interfaces_to_take_down_size,

2553

interface))){

2554

ret_errno = take_down_interface(interface);

2555

if(ret_errno != 0){

2556

errno = ret_errno;

2557

perror_plus("Failed to take down interface");

2558

}

2559

}

2560

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

2561

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

2562

" down\n");

2563

}

2564

}

2250

2565

}

2251

2566

2252

/* Take down the network interface */

2253

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

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

2567

ret_errno = lower_privileges_permanently();

2568

if(ret_errno != 0){

2569

perror_plus("Failed to lower privileges permanently");

2268

2570

}

2269

2571

}

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2572

2573

free(interfaces_to_take_down);

2574

free(interfaces_hooks);

2276

2575

2277

2576

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

2278

if(tempdir_created){

2577

if(tempdir != NULL){

2279

2578

struct dirent **direntries = NULL;

2280

2579

struct dirent *direntry = NULL;

2281

2580

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

2282

2581

alphasort);

2283

if (numentries > 0){

2582

if(numentries > 0){

2284

2583

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

2285

2584

direntry = direntries[i];

2286

2585

char *fullname = NULL;

2298

2597

free(fullname);

2299

2598

}

2300

2599

}

2301

2600

2302

2601

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

2303

2602

free(direntries);

2304

if (numentries == -1){

2603

if(numentries == -1){

2305

2604

perror_plus("scandir");

2306

2605

}

2307

2606

ret = rmdir(tempdir);