/mandos/trunk : revision 748

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

10

*

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* Everything else is

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12

13

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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

32

/* Needed by GPGME, specifically gpgme_data_seek() */

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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40

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

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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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stdout, ferror() */

44

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

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inet_pton(), connect(),

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getnameinfo() */

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

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61

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

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62

*/

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63

#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() */

73

*/

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

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unlinkat() */

78

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

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

79

80

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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98

92

99

#ifdef __linux__

93

100

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

135

142

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

136

143

char *connect_to = NULL;

137

144

const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

146

uid_t uid = 65534;

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gid_t gid = 65534;

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148

139

149

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

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150

typedef struct server{

141

151

const char *ip;

142

uint16_t port;

152

in_port_t port;

143

153

AvahiIfIndex if_index;

144

154

int af;

145

155

struct timespec last_seen;

149

159

150

160

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

151

161

typedef struct {

152

AvahiSimplePoll *simple_poll;

153

162

AvahiServer *server;

154

163

gnutls_certificate_credentials_t cred;

155

164

unsigned int dh_bits;

157

166

const char *priority;

158

167

gpgme_ctx_t ctx;

159

168

server *current_server;

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char *interfaces;

170

size_t interfaces_size;

160

171

} mandos_context;

161

172

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

167

175

168

176

sig_atomic_t quit_now = 0;

169

177

int signal_received = 0;

170

178

171

179

/* Function to use when printing errors */

172

180

void perror_plus(const char *print_text){

181

int e = errno;

173

182

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

174

183

program_invocation_short_name);

184

errno = e;

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185

perror(print_text);

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186

}

177

187

188

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

178

189

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

179

190

va_list ap;

180

191

va_start (ap, format);

181

192

182

193

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

183

194

program_invocation_short_name));

184

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

195

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

185

196

}

186

197

187

198

/*

189

200

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

190

201

* "buffer_length" is how much is already used.

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202

*/

203

__attribute__((nonnull, warn_unused_result))

192

204

size_t incbuffer(char **buffer, size_t buffer_length,

193

205

size_t buffer_capacity){

194

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

195

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

196

if(buffer == NULL){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

197

213

return 0;

198

214

}

215

*buffer = new_buf;

199

216

buffer_capacity += BUFFER_SIZE;

200

217

}

201

218

return buffer_capacity;

202

219

}

203

220

204

221

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

205

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

206

int af){

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

207

225

int ret;

208

226

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

209

227

if(new_server == NULL){

210

228

perror_plus("malloc");

211

return -1;

229

return false;

212

230

}

213

231

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

214

232

.port = port,

216

234

.af = af };

217

235

if(new_server->ip == NULL){

218

236

perror_plus("strdup");

219

return -1;

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

220

253

}

221

254

/* Special case of first server */

222

if (mc.current_server == NULL){

255

if(*current_server == NULL){

223

256

new_server->next = new_server;

224

257

new_server->prev = new_server;

225

mc.current_server = new_server;

226

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

258

*current_server = new_server;

227

259

} else {

228

new_server->next = mc.current_server;

229

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

260

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

261

new_server->next = *current_server;

262

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

230

263

new_server->prev->next = new_server;

231

mc.current_server->prev = new_server;

232

}

233

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

236

return -1;

237

}

238

return 0;

264

(*current_server)->prev = new_server;

265

}

266

return true;

239

267

}

240

268

241

269

/*

242

270

* Initialize GPGME.

243

271

*/

244

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

245

const char *tempdir){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

246

277

gpgme_error_t rc;

247

278

gpgme_engine_info_t engine_info;

248

279

249

250

280

/*

251

281

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

252

282

*/

253

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

254

284

int ret;

255

285

int fd;

256

286

gpgme_data_t pgp_data;

268

298

return false;

269

299

}

270

300

271

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

272

302

if(rc != GPG_ERR_NO_ERROR){

273

303

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

274

304

gpgme_strsource(rc), gpgme_strerror(rc));

318

348

}

319

349

320

350

/* Create new GPGME "context" */

321

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

351

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

322

352

if(rc != GPG_ERR_NO_ERROR){

323

353

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

324

354

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

337

367

* Decrypt OpenPGP data.

338

368

* Returns -1 on error

339

369

*/

370

__attribute__((nonnull, warn_unused_result))

340

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

341

372

size_t crypto_size,

342

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

343

375

gpgme_data_t dh_crypto, dh_plain;

344

376

gpgme_error_t rc;

345

377

ssize_t ret;

371

403

372

404

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

373

405

data buffer */

374

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

406

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

375

407

if(rc != GPG_ERR_NO_ERROR){

376

408

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

377

409

gpgme_strsource(rc), gpgme_strerror(rc));

378

410

plaintext_length = -1;

379

411

if(debug){

380

412

gpgme_decrypt_result_t result;

381

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

382

414

if(result == NULL){

383

415

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

384

416

} else {

461

493

return plaintext_length;

462

494

}

463

495

464

static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

467

if(ret == NULL)

468

ret = "(unknown)";

469

return ret;

496

__attribute__((warn_unused_result, const))

497

static const char *safe_string(const char *str){

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

__attribute__((warn_unused_result))

504

static const char *safer_gnutls_strerror(int value){

505

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

470

507

}

471

508

472

509

/* GnuTLS log function callback */

510

__attribute__((nonnull))

473

511

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

474

512

const char* string){

475

513

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

476

514

}

477

515

516

__attribute__((nonnull, warn_unused_result))

478

517

static int init_gnutls_global(const char *pubkeyfilename,

479

const char *seckeyfilename){

518

const char *seckeyfilename,

519

mandos_context *mc){

480

520

int ret;

521

unsigned int uret;

481

522

482

523

if(debug){

483

524

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

499

540

}

500

541

501

542

/* OpenPGP credentials */

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

503

544

if(ret != GNUTLS_E_SUCCESS){

504

545

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

505

546

safer_gnutls_strerror(ret));

515

556

}

516

557

517

558

ret = gnutls_certificate_set_openpgp_key_file

518

(mc.cred, pubkeyfilename, seckeyfilename,

559

(mc->cred, pubkeyfilename, seckeyfilename,

519

560

GNUTLS_OPENPGP_FMT_BASE64);

520

561

if(ret != GNUTLS_E_SUCCESS){

521

562

fprintf_plus(stderr,

527

568

}

528

569

529

570

/* GnuTLS server initialization */

530

ret = gnutls_dh_params_init(&mc.dh_params);

571

ret = gnutls_dh_params_init(&mc->dh_params);

531

572

if(ret != GNUTLS_E_SUCCESS){

532

573

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

533

574

" initialization: %s\n",

534

575

safer_gnutls_strerror(ret));

535

576

goto globalfail;

536

577

}

537

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

578

if(mc->dh_bits == 0){

579

/* Find out the optimal number of DH bits */

580

/* Try to read the private key file */

581

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

582

{

583

int secfile = open(seckeyfilename, O_RDONLY);

584

size_t buffer_capacity = 0;

585

while(true){

586

buffer_capacity = incbuffer((char **)&buffer.data,

587

(size_t)buffer.size,

588

(size_t)buffer_capacity);

589

if(buffer_capacity == 0){

590

perror_plus("incbuffer");

591

free(buffer.data);

592

buffer.data = NULL;

593

break;

594

}

595

ssize_t bytes_read = read(secfile, buffer.data + buffer.size,

596

BUFFER_SIZE);

597

/* EOF */

598

if(bytes_read == 0){

599

break;

600

}

601

/* check bytes_read for failure */

602

if(bytes_read < 0){

603

perror_plus("read");

604

free(buffer.data);

605

buffer.data = NULL;

606

break;

607

}

608

buffer.size += (unsigned int)bytes_read;

609

}

610

close(secfile);

611

}

612

/* If successful, use buffer to parse private key */

613

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

614

if(buffer.data != NULL){

615

{

616

gnutls_openpgp_privkey_t privkey = NULL;

617

ret = gnutls_openpgp_privkey_init(&privkey);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Error initializing OpenPGP key"

620

" structure: %s", safer_gnutls_strerror(ret));

621

free(buffer.data);

622

buffer.data = NULL;

623

} else {

624

ret = gnutls_openpgp_privkey_import(privkey, &buffer,

625

GNUTLS_OPENPGP_FMT_BASE64,

626

"", 0);

627

if(ret != GNUTLS_E_SUCCESS){

628

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

629

safer_gnutls_strerror(ret));

630

privkey = NULL;

631

}

632

free(buffer.data);

633

buffer.data = NULL;

634

if(privkey != NULL){

635

/* Use private key to suggest an appropriate sec_param */

636

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

637

gnutls_openpgp_privkey_deinit(privkey);

638

if(debug){

639

fprintf_plus(stderr, "This OpenPGP key implies using a"

640

" GnuTLS security parameter \"%s\".\n",

641

safe_string(gnutls_sec_param_get_name

642

(sec_param)));

643

}

644

}

645

}

646

}

647

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

648

/* Err on the side of caution */

649

sec_param = GNUTLS_SEC_PARAM_ULTRA;

650

if(debug){

651

fprintf_plus(stderr, "Falling back to security parameter"

652

" \"%s\"\n",

653

safe_string(gnutls_sec_param_get_name

654

(sec_param)));

655

}

656

}

657

}

658

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

659

if(uret != 0){

660

mc->dh_bits = uret;

661

if(debug){

662

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

663

" implies %u DH bits; using that.\n",

664

safe_string(gnutls_sec_param_get_name

665

(sec_param)),

666

mc->dh_bits);

667

}

668

} else {

669

fprintf_plus(stderr, "Failed to get implied number of DH"

670

" bits for security parameter \"%s\"): %s\n",

671

safe_string(gnutls_sec_param_get_name(sec_param)),

672

safer_gnutls_strerror(ret));

673

goto globalfail;

674

}

675

} else if(debug){

676

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

677

mc->dh_bits);

678

}

679

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

538

680

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

681

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u bits):"

682

" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));

541

683

goto globalfail;

542

684

}

543

685

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

686

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

545

687

546

688

return 0;

547

689

548

690

globalfail:

549

691

550

gnutls_certificate_free_credentials(mc.cred);

692

gnutls_certificate_free_credentials(mc->cred);

551

693

gnutls_global_deinit();

552

gnutls_dh_params_deinit(mc.dh_params);

694

gnutls_dh_params_deinit(mc->dh_params);

553

695

return -1;

554

696

}

555

697

556

static int init_gnutls_session(gnutls_session_t *session){

698

__attribute__((nonnull, warn_unused_result))

699

static int init_gnutls_session(gnutls_session_t *session,

700

mandos_context *mc){

557

701

int ret;

558

702

/* GnuTLS session creation */

559

703

do {

571

715

{

572

716

const char *err;

573

717

do {

574

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

718

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

575

719

if(quit_now){

576

720

gnutls_deinit(*session);

577

721

return -1;

588

732

589

733

do {

590

734

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

591

mc.cred);

735

mc->cred);

592

736

if(quit_now){

593

737

gnutls_deinit(*session);

594

738

return -1;

604

748

/* ignore client certificate if any. */

605

749

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

606

750

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

751

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

608

752

609

753

return 0;

610

754

}

614

758

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

615

759

616

760

/* Called when a Mandos server is found */

617

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

761

__attribute__((nonnull, warn_unused_result))

762

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

618

763

AvahiIfIndex if_index,

619

int af){

764

int af, mandos_context *mc){

620

765

int ret, tcp_sd = -1;

621

766

ssize_t sret;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

767

struct sockaddr_storage to;

626

768

char *buffer = NULL;

627

769

char *decrypted_buffer = NULL;

628

770

size_t buffer_length = 0;

652

794

return -1;

653

795

}

654

796

655

ret = init_gnutls_session(&session);

797

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

798

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

799

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

800

bool match = false;

801

{

802

char *interface = NULL;

803

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

804

interface))){

805

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

806

match = true;

807

break;

808

}

809

}

810

}

811

if(not match){

812

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

813

connect to the server */

814

if(debug){

815

char interface[IF_NAMESIZE];

816

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

817

perror_plus("if_indextoname");

818

} else {

819

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

820

" \"%s\"\n",

821

if_indextoname((unsigned int)if_index,

822

interface));

823

}

824

}

825

return -1;

826

}

827

}

828

829

ret = init_gnutls_session(&session, mc);

656

830

if(ret != 0){

657

831

return -1;

658

832

}

659

833

660

834

if(debug){

661

835

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

662

PRIu16 "\n", ip, port);

836

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

663

837

}

664

838

665

839

tcp_sd = socket(pf, SOCK_STREAM, 0);

677

851

678

852

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

679

853

if(af == AF_INET6){

680

to.in6.sin6_family = (sa_family_t)af;

681

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

854

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

855

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

682

856

} else { /* IPv4 */

683

to.in.sin_family = (sa_family_t)af;

684

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

857

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

858

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

685

859

}

686

860

if(ret < 0 ){

687

861

int e = errno;

696

870

goto mandos_end;

697

871

}

698

872

if(af == AF_INET6){

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

873

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

874

if(IN6_IS_ADDR_LINKLOCAL

875

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

706

876

if(if_index == AVAHI_IF_UNSPEC){

707

877

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

708

878

" incomplete without a network interface\n");

710

880

goto mandos_end;

711

881

}

712

882

/* Set the network interface number as scope */

713

to.in6.sin6_scope_id = (uint32_t)if_index;

883

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

714

884

}

715

885

} else {

716

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

717

-Wconversion and

718

-Wunreachable-code */

886

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

719

887

}

720

888

721

889

if(quit_now){

729

897

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

730

898

perror_plus("if_indextoname");

731

899

} else {

732

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

733

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

900

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

901

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

734

902

}

735

903

} else {

736

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

737

ip, port);

904

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

905

ip, (uintmax_t)port);

738

906

}

739

907

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

740

908

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

741

const char *pcret;

742

909

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

910

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

911

sizeof(struct sockaddr_in6),

912

addrstr, sizeof(addrstr), NULL, 0,

913

NI_NUMERICHOST);

745

914

} else {

746

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

747

sizeof(addrstr));

915

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

916

sizeof(struct sockaddr_in),

917

addrstr, sizeof(addrstr), NULL, 0,

918

NI_NUMERICHOST);

748

919

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

920

if(ret == EAI_SYSTEM){

921

perror_plus("getnameinfo");

922

} else if(ret != 0) {

923

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

924

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

925

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

755

926

}

756

927

}

757

928

761

932

}

762

933

763

934

if(af == AF_INET6){

764

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

935

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

936

sizeof(struct sockaddr_in6));

765

937

} else {

766

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

938

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

939

sizeof(struct sockaddr_in));

767

940

}

768

941

if(ret < 0){

769

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

942

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

770

943

int e = errno;

771

944

perror_plus("connect");

772

945

errno = e;

818

991

goto mandos_end;

819

992

}

820

993

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

994

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

995

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

996

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

997

gnutls_transport_set_ptr(session,

998

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

823

999

824

1000

if(quit_now){

825

1001

errno = EINTR;

930

1106

if(buffer_length > 0){

931

1107

ssize_t decrypted_buffer_size;

932

1108

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

933

&decrypted_buffer);

1109

&decrypted_buffer, mc);

934

1110

if(decrypted_buffer_size >= 0){

935

1111

936

1112

written = 0;

984

1160

return retval;

985

1161

}

986

1162

1163

__attribute__((nonnull))

987

1164

static void resolve_callback(AvahiSServiceResolver *r,

988

1165

AvahiIfIndex interface,

989

1166

AvahiProtocol proto,

997

1174

AVAHI_GCC_UNUSED AvahiStringList *txt,

998

1175

AVAHI_GCC_UNUSED AvahiLookupResultFlags

999

1176

flags,

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1177

void *mc){

1178

if(r == NULL){

1179

return;

1180

}

1002

1181

1003

1182

/* Called whenever a service has been resolved successfully or

1004

1183

timed out */

1005

1184

1006

1185

if(quit_now){

1186

avahi_s_service_resolver_free(r);

1007

1187

return;

1008

1188

}

1009

1189

1013

1193

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

1014

1194

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

1015

1195

domain,

1016

avahi_strerror(avahi_server_errno(mc.server)));

1196

avahi_strerror(avahi_server_errno

1197

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

1017

1198

break;

1018

1199

1019

1200

case AVAHI_RESOLVER_FOUND:

1025

1206

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

1026

1207

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

1027

1208

}

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1209

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

1210

interface,

1211

avahi_proto_to_af(proto),

1212

mc);

1030

1213

if(ret == 0){

1031

avahi_simple_poll_quit(mc.simple_poll);

1214

avahi_simple_poll_quit(simple_poll);

1032

1215

} else {

1033

ret = add_server(ip, port, interface,

1034

avahi_proto_to_af(proto));

1216

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

1217

avahi_proto_to_af(proto),

1218

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

1219

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

1220

" list\n", name);

1221

}

1035

1222

}

1036

1223

}

1037

1224

}

1047

1234

const char *domain,

1048

1235

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1049

1236

flags,

1050

AVAHI_GCC_UNUSED void* userdata){

1051

assert(b);

1237

void *mc){

1238

if(b == NULL){

1239

return;

1240

}

1052

1241

1053

1242

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

1054

1243

is removed from the LAN */

1062

1251

case AVAHI_BROWSER_FAILURE:

1063

1252

1064

1253

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

1065

avahi_strerror(avahi_server_errno(mc.server)));

1066

avahi_simple_poll_quit(mc.simple_poll);

1254

avahi_strerror(avahi_server_errno

1255

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

1256

avahi_simple_poll_quit(simple_poll);

1067

1257

return;

1068

1258

1069

1259

case AVAHI_BROWSER_NEW:

1072

1262

the callback function is called the Avahi server will free the

1073

1263

resolver for us. */

1074

1264

1075

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

1076

name, type, domain, protocol, 0,

1077

resolve_callback, NULL) == NULL)

1265

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

1266

interface, protocol, name, type,

1267

domain, protocol, 0,

1268

resolve_callback, mc) == NULL)

1078

1269

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

1079

1270

" %s\n", name,

1080

avahi_strerror(avahi_server_errno(mc.server)));

1271

avahi_strerror(avahi_server_errno

1272

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

1081

1273

break;

1082

1274

1083

1275

case AVAHI_BROWSER_REMOVE:

1102

1294

signal_received = sig;

1103

1295

int old_errno = errno;

1104

1296

/* set main loop to exit */

1105

if(mc.simple_poll != NULL){

1106

avahi_simple_poll_quit(mc.simple_poll);

1297

if(simple_poll != NULL){

1298

avahi_simple_poll_quit(simple_poll);

1107

1299

}

1108

1300

errno = old_errno;

1109

1301

}

1110

1302

1303

__attribute__((nonnull, warn_unused_result))

1111

1304

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

1112

1305

int ret;

1306

error_t ret_errno;

1113

1307

1114

1308

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

1115

1309

if(s < 0){

1310

ret_errno = errno;

1116

1311

perror_plus("socket");

1312

errno = ret_errno;

1117

1313

return false;

1118

1314

}

1119

1315

strcpy(ifr->ifr_name, ifname);

1120

1316

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1121

1317

if(ret == -1){

1122

1318

if(debug){

1319

ret_errno = errno;

1123

1320

perror_plus("ioctl SIOCGIFFLAGS");

1321

errno = ret_errno;

1124

1322

}

1125

1323

return false;

1126

1324

}

1127

1325

return true;

1128

1326

}

1129

1327

1328

__attribute__((nonnull, warn_unused_result))

1130

1329

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

1131

1330

1132

1331

/* Reject the loopback device */

1174

1373

* corresponds to an acceptable network device.

1175

1374

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

1176

1375

*/

1376

__attribute__((nonnull, warn_unused_result))

1177

1377

int good_interface(const struct dirent *if_entry){

1178

1378

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

1179

1379

return 0;

1195

1395

}

1196

1396

1197

1397

/*

1198

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

1199

* corresponds to an acceptable network device which is up.

1200

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

1201

*/

1202

int up_interface(const struct dirent *if_entry){

1203

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

1204

return 0;

1205

}

1206

1207

struct ifreq ifr;

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return 0;

1214

}

1215

1216

/* Reject down interfaces */

1217

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

1218

if(debug){

1219

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

1220

if_entry->d_name);

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject non-running interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

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

1235

return 0;

1236

}

1237

return 1;

1238

}

1239

1398

* This function determines if a network interface is up.

1399

*/

1400

__attribute__((nonnull, warn_unused_result))

1401

bool interface_is_up(const char *interface){

1402

struct ifreq ifr;

1403

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

1404

if(debug){

1405

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

1406

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

1407

}

1408

return false;

1409

}

1410

1411

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

1412

}

1413

1414

/*

1415

* This function determines if a network interface is running

1416

*/

1417

__attribute__((nonnull, warn_unused_result))

1418

bool interface_is_running(const char *interface){

1419

struct ifreq ifr;

1420

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

1421

if(debug){

1422

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

1423

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

1424

}

1425

return false;

1426

}

1427

1428

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

1429

}

1430

1431

__attribute__((nonnull, pure, warn_unused_result))

1240

1432

int notdotentries(const struct dirent *direntry){

1241

1433

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

1242

1434

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

1249

1441

}

1250

1442

1251

1443

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

1444

__attribute__((nonnull, warn_unused_result))

1252

1445

int runnable_hook(const struct dirent *direntry){

1253

1446

int ret;

1254

1447

size_t sret;

1262

1455

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

1263

1456

"abcdefghijklmnopqrstuvwxyz"

1264

1457

"0123456789"

1265

"_-");

1458

"_.-");

1266

1459

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

1267

1460

/* Contains non-allowed characters */

1268

1461

if(debug){

1272

1465

return 0;

1273

1466

}

1274

1467

1275

char *fullname = NULL;

1276

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

1277

if(ret < 0){

1278

perror_plus("asprintf");

1279

return 0;

1280

}

1281

1282

ret = stat(fullname, &st);

1468

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

1283

1469

if(ret == -1){

1284

1470

if(debug){

1285

1471

perror_plus("Could not stat hook");

1309

1495

return 1;

1310

1496

}

1311

1497

1312

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1498

__attribute__((nonnull, warn_unused_result))

1499

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1500

mandos_context *mc){

1313

1501

int ret;

1314

1502

struct timespec now;

1315

1503

struct timespec waited_time;

1316

1504

intmax_t block_time;

1317

1505

1318

1506

while(true){

1319

if(mc.current_server == NULL){

1320

if (debug){

1507

if(mc->current_server == NULL){

1508

if(debug){

1321

1509

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

1322

1510

" No timeout!\n");

1323

1511

}

1324

1512

ret = avahi_simple_poll_iterate(s, -1);

1325

1513

} else {

1326

if (debug){

1514

if(debug){

1327

1515

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

1328

1516

" it, or wait\n");

1329

1517

}

1336

1524

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

1337

1525

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

1338

1526

waited_time.tv_sec = (now.tv_sec

1339

- mc.current_server->last_seen.tv_sec);

1527

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

1340

1528

waited_time.tv_nsec = (now.tv_nsec

1341

- mc.current_server->last_seen.tv_nsec);

1529

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

1342

1530

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

1343

1531

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

1344

1532

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

1346

1534

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

1347

1535

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

1348

1536

1349

if (debug){

1537

if(debug){

1350

1538

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

1351

1539

block_time);

1352

1540

}

1353

1541

1354

1542

if(block_time <= 0){

1355

ret = start_mandos_communication(mc.current_server->ip,

1356

mc.current_server->port,

1357

mc.current_server->if_index,

1358

mc.current_server->af);

1543

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

1544

mc->current_server->port,

1545

mc->current_server->if_index,

1546

mc->current_server->af, mc);

1359

1547

if(ret == 0){

1360

avahi_simple_poll_quit(mc.simple_poll);

1548

avahi_simple_poll_quit(s);

1361

1549

return 0;

1362

1550

}

1363

1551

ret = clock_gettime(CLOCK_MONOTONIC,

1364

&mc.current_server->last_seen);

1552

&mc->current_server->last_seen);

1365

1553

if(ret == -1){

1366

1554

perror_plus("clock_gettime");

1367

1555

return -1;

1368

1556

}

1369

mc.current_server = mc.current_server->next;

1557

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

1370

1558

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

1371

1559

servers, but don't block */

1372

1560

}

1374

1562

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

1375

1563

}

1376

1564

if(ret != 0){

1377

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

1565

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

1378

1566

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

1379

1567

}

1380

1568

}

1381

1569

}

1382

1570

}

1383

1571

1384

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

1572

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

1573

__attribute__((warn_unused_result))

1574

error_t raise_privileges(void){

1575

error_t old_errno = errno;

1576

error_t ret_errno = 0;

1577

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

1578

ret_errno = errno;

1579

}

1580

errno = old_errno;

1581

return ret_errno;

1582

}

1583

1584

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

1585

__attribute__((warn_unused_result))

1586

error_t raise_privileges_permanently(void){

1587

error_t old_errno = errno;

1588

error_t ret_errno = raise_privileges();

1589

if(ret_errno != 0){

1590

errno = old_errno;

1591

return ret_errno;

1592

}

1593

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

1594

ret_errno = errno;

1595

}

1596

errno = old_errno;

1597

return ret_errno;

1598

}

1599

1600

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

1601

__attribute__((warn_unused_result))

1602

error_t lower_privileges(void){

1603

error_t old_errno = errno;

1604

error_t ret_errno = 0;

1605

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

1606

ret_errno = errno;

1607

}

1608

errno = old_errno;

1609

return ret_errno;

1610

}

1611

1612

/* Lower privileges permanently */

1613

__attribute__((warn_unused_result))

1614

error_t lower_privileges_permanently(void){

1615

error_t old_errno = errno;

1616

error_t ret_errno = 0;

1617

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

1618

ret_errno = errno;

1619

}

1620

errno = old_errno;

1621

return ret_errno;

1622

}

1623

1624

__attribute__((nonnull))

1625

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

1385

1626

const float delay){

1386

struct dirent **direntries;

1387

struct dirent *direntry;

1388

int ret;

1389

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

1390

alphasort);

1627

struct dirent **direntries = NULL;

1628

if(hookdir_fd == -1){

1629

hookdir_fd = open(hookdir, O_RDONLY);

1630

if(hookdir_fd == -1){

1631

if(errno == ENOENT){

1632

if(debug){

1633

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

1634

" found\n", hookdir);

1635

}

1636

} else {

1637

perror_plus("open");

1638

}

1639

return;

1640

}

1641

}

1642

#ifdef __GLIBC__

1643

#if __GLIBC_PREREQ(2, 15)

1644

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1645

runnable_hook, alphasort);

1646

#else /* not __GLIBC_PREREQ(2, 15) */

1647

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

1648

alphasort);

1649

#endif /* not __GLIBC_PREREQ(2, 15) */

1650

#else /* not __GLIBC__ */

1651

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

1652

alphasort);

1653

#endif /* not __GLIBC__ */

1391

1654

if(numhooks == -1){

1392

1655

perror_plus("scandir");

1393

} else {

1394

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

1395

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

1396

direntry = direntries[i];

1397

char *fullname = NULL;

1398

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

1399

if(ret < 0){

1656

return;

1657

}

1658

struct dirent *direntry;

1659

int ret;

1660

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

1661

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

1662

direntry = direntries[i];

1663

if(debug){

1664

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

1665

direntry->d_name);

1666

}

1667

pid_t hook_pid = fork();

1668

if(hook_pid == 0){

1669

/* Child */

1670

/* Raise privileges */

1671

errno = raise_privileges_permanently();

1672

if(errno != 0){

1673

perror_plus("Failed to raise privileges");

1674

_exit(EX_NOPERM);

1675

}

1676

/* Set group */

1677

errno = 0;

1678

ret = setgid(0);

1679

if(ret == -1){

1680

perror_plus("setgid");

1681

_exit(EX_NOPERM);

1682

}

1683

/* Reset supplementary groups */

1684

errno = 0;

1685

ret = setgroups(0, NULL);

1686

if(ret == -1){

1687

perror_plus("setgroups");

1688

_exit(EX_NOPERM);

1689

}

1690

ret = dup2(devnull, STDIN_FILENO);

1691

if(ret == -1){

1692

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

1693

_exit(EX_OSERR);

1694

}

1695

ret = close(devnull);

1696

if(ret == -1){

1697

perror_plus("close");

1698

_exit(EX_OSERR);

1699

}

1700

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1701

if(ret == -1){

1702

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

1703

_exit(EX_OSERR);

1704

}

1705

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

1706

if(ret == -1){

1707

perror_plus("setenv");

1708

_exit(EX_OSERR);

1709

}

1710

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

1711

if(ret == -1){

1712

perror_plus("setenv");

1713

_exit(EX_OSERR);

1714

}

1715

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

1716

if(ret == -1){

1717

perror_plus("setenv");

1718

_exit(EX_OSERR);

1719

}

1720

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

1721

if(ret == -1){

1722

perror_plus("setenv");

1723

_exit(EX_OSERR);

1724

}

1725

char *delaystring;

1726

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

1727

if(ret == -1){

1400

1728

perror_plus("asprintf");

1401

continue;

1402

}

1403

if(debug){

1404

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

1405

direntry->d_name);

1406

}

1407

pid_t hook_pid = fork();

1408

if(hook_pid == 0){

1409

/* Child */

1410

/* Raise privileges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror_plus("seteuid");

1415

}

1416

/* Raise privileges even more */

1417

errno = 0;

1418

ret = setuid(0);

1419

if(ret == -1){

1420

perror_plus("setuid");

1421

}

1422

/* Set group */

1423

errno = 0;

1424

ret = setgid(0);

1425

if(ret == -1){

1426

perror_plus("setgid");

1427

}

1428

/* Reset supplementary groups */

1429

errno = 0;

1430

ret = setgroups(0, NULL);

1431

if(ret == -1){

1432

perror_plus("setgroups");

1433

}

1434

fprintf_plus(stderr, "Child: getuid() = %d\n", getuid());

1435

fprintf_plus(stderr, "Child: geteuid() = %d\n", geteuid());

1436

dup2(devnull, STDIN_FILENO);

1437

close(devnull);

1438

dup2(STDERR_FILENO, STDOUT_FILENO);

1439

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

1440

if(ret == -1){

1441

perror_plus("setenv");

1442

_exit(EX_OSERR);

1443

}

1444

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

1445

if(ret == -1){

1446

perror_plus("setenv");

1447

_exit(EX_OSERR);

1448

}

1449

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

1450

if(ret == -1){

1451

perror_plus("setenv");

1452

_exit(EX_OSERR);

1453

}

1454

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

1455

if(ret == -1){

1456

perror_plus("setenv");

1457

_exit(EX_OSERR);

1458

}

1459

char *delaystring;

1460

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

1461

if(ret == -1){

1462

perror_plus("asprintf");

1463

_exit(EX_OSERR);

1464

}

1465

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

1466

if(ret == -1){

1467

free(delaystring);

1468

perror_plus("setenv");

1469

_exit(EX_OSERR);

1470

}

1729

_exit(EX_OSERR);

1730

}

1731

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

1732

if(ret == -1){

1471

1733

free(delaystring);

1472

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

1473

perror_plus("execl");

1474

} else {

1475

int status;

1476

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

1477

perror_plus("waitpid");

1478

free(fullname);

1479

continue;

1480

}

1481

if(WIFEXITED(status)){

1482

if(WEXITSTATUS(status) != 0){

1483

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

1484

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

1485

WEXITSTATUS(status));

1486

free(fullname);

1487

continue;

1488

}

1489

} else if(WIFSIGNALED(status)){

1490

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

1491

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

1492

WTERMSIG(status));

1493

free(fullname);

1494

continue;

1495

} else {

1496

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

1497

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

1498

free(fullname);

1499

continue;

1500

}

1501

}

1502

free(fullname);

1503

if(debug){

1504

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

1505

direntry->d_name);

1506

}

1507

}

1508

close(devnull);

1509

}

1510

return true;

1734

perror_plus("setenv");

1735

_exit(EX_OSERR);

1736

}

1737

free(delaystring);

1738

if(connect_to != NULL){

1739

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

1740

if(ret == -1){

1741

perror_plus("setenv");

1742

_exit(EX_OSERR);

1743

}

1744

}

1745

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1746

if(hook_fd == -1){

1747

perror_plus("openat");

1748

_exit(EXIT_FAILURE);

1749

}

1750

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1751

perror_plus("close");

1752

_exit(EXIT_FAILURE);

1753

}

1754

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

1755

environ) == -1){

1756

perror_plus("fexecve");

1757

_exit(EXIT_FAILURE);

1758

}

1759

} else {

1760

if(hook_pid == -1){

1761

perror_plus("fork");

1762

free(direntry);

1763

continue;

1764

}

1765

int status;

1766

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

1767

perror_plus("waitpid");

1768

free(direntry);

1769

continue;

1770

}

1771

if(WIFEXITED(status)){

1772

if(WEXITSTATUS(status) != 0){

1773

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

1774

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

1775

WEXITSTATUS(status));

1776

free(direntry);

1777

continue;

1778

}

1779

} else if(WIFSIGNALED(status)){

1780

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

1781

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

1782

WTERMSIG(status));

1783

free(direntry);

1784

continue;

1785

} else {

1786

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

1787

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

1788

free(direntry);

1789

continue;

1790

}

1791

}

1792

if(debug){

1793

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

1794

direntry->d_name);

1795

}

1796

free(direntry);

1797

}

1798

free(direntries);

1799

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1800

perror_plus("close");

1801

} else {

1802

hookdir_fd = -1;

1803

}

1804

close(devnull);

1805

}

1806

1807

__attribute__((nonnull, warn_unused_result))

1808

error_t bring_up_interface(const char *const interface,

1809

const float delay){

1810

error_t old_errno = errno;

1811

int ret;

1812

struct ifreq network;

1813

unsigned int if_index = if_nametoindex(interface);

1814

if(if_index == 0){

1815

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

1816

errno = old_errno;

1817

return ENXIO;

1818

}

1819

1820

if(quit_now){

1821

errno = old_errno;

1822

return EINTR;

1823

}

1824

1825

if(not interface_is_up(interface)){

1826

error_t ret_errno = 0, ioctl_errno = 0;

1827

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

1828

ret_errno = errno;

1829

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

1830

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

1831

errno = old_errno;

1832

return ret_errno;

1833

}

1834

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

1835

1836

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

1837

if(sd == -1){

1838

ret_errno = errno;

1839

perror_plus("socket");

1840

errno = old_errno;

1841

return ret_errno;

1842

}

1843

1844

if(quit_now){

1845

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

1846

if(ret == -1){

1847

perror_plus("close");

1848

}

1849

errno = old_errno;

1850

return EINTR;

1851

}

1852

1853

if(debug){

1854

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

1855

interface);

1856

}

1857

1858

/* Raise privileges */

1859

ret_errno = raise_privileges();

1860

if(ret_errno != 0){

1861

errno = ret_errno;

1862

perror_plus("Failed to raise privileges");

1863

}

1864

1865

#ifdef __linux__

1866

int ret_linux;

1867

bool restore_loglevel = false;

1868

if(ret_errno == 0){

1869

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1870

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

1871

ret_linux = klogctl(8, NULL, 5);

1872

if(ret_linux == -1){

1873

perror_plus("klogctl");

1874

} else {

1875

restore_loglevel = true;

1876

}

1877

}

1878

#endif /* __linux__ */

1879

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

1880

ioctl_errno = errno;

1881

#ifdef __linux__

1882

if(restore_loglevel){

1883

ret_linux = klogctl(7, NULL, 0);

1884

if(ret_linux == -1){

1885

perror_plus("klogctl");

1886

}

1887

}

1888

#endif /* __linux__ */

1889

1890

/* If raise_privileges() succeeded above */

1891

if(ret_errno == 0){

1892

/* Lower privileges */

1893

ret_errno = lower_privileges();

1894

if(ret_errno != 0){

1895

errno = ret_errno;

1896

perror_plus("Failed to lower privileges");

1897

}

1898

}

1899

1900

/* Close the socket */

1901

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

1902

if(ret == -1){

1903

perror_plus("close");

1904

}

1905

1906

if(ret_setflags == -1){

1907

errno = ioctl_errno;

1908

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1909

errno = old_errno;

1910

return ioctl_errno;

1911

}

1912

} else if(debug){

1913

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

1914

interface);

1915

}

1916

1917

/* Sleep checking until interface is running.

1918

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

1919

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

1920

if(interface_is_running(interface)){

1921

break;

1922

}

1923

struct timespec sleeptime = { .tv_nsec = 250000000 };

1924

ret = nanosleep(&sleeptime, NULL);

1925

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

1926

perror_plus("nanosleep");

1927

}

1928

}

1929

1930

errno = old_errno;

1931

return 0;

1932

}

1933

1934

__attribute__((nonnull, warn_unused_result))

1935

error_t take_down_interface(const char *const interface){

1936

error_t old_errno = errno;

1937

struct ifreq network;

1938

unsigned int if_index = if_nametoindex(interface);

1939

if(if_index == 0){

1940

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

1941

errno = old_errno;

1942

return ENXIO;

1943

}

1944

if(interface_is_up(interface)){

1945

error_t ret_errno = 0, ioctl_errno = 0;

1946

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

1947

ret_errno = errno;

1948

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

1949

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

1950

errno = old_errno;

1951

return ret_errno;

1952

}

1953

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

1954

1955

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

1956

if(sd == -1){

1957

ret_errno = errno;

1958

perror_plus("socket");

1959

errno = old_errno;

1960

return ret_errno;

1961

}

1962

1963

if(debug){

1964

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

1965

interface);

1966

}

1967

1968

/* Raise privileges */

1969

ret_errno = raise_privileges();

1970

if(ret_errno != 0){

1971

errno = ret_errno;

1972

perror_plus("Failed to raise privileges");

1973

}

1974

1975

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

1976

ioctl_errno = errno;

1977

1978

/* If raise_privileges() succeeded above */

1979

if(ret_errno == 0){

1980

/* Lower privileges */

1981

ret_errno = lower_privileges();

1982

if(ret_errno != 0){

1983

errno = ret_errno;

1984

perror_plus("Failed to lower privileges");

1985

}

1986

}

1987

1988

/* Close the socket */

1989

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

1990

if(ret == -1){

1991

perror_plus("close");

1992

}

1993

1994

if(ret_setflags == -1){

1995

errno = ioctl_errno;

1996

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1997

errno = old_errno;

1998

return ioctl_errno;

1999

}

2000

} else if(debug){

2001

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

2002

interface);

2003

}

2004

2005

errno = old_errno;

2006

return 0;

1511

2007

}

1512

2008

1513

2009

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

2010

mandos_context mc = { .server = NULL, .dh_bits = 0,

2011

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

2012

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

2013

.interfaces = NULL, .interfaces_size = 0 };

1514

2014

AvahiSServiceBrowser *sb = NULL;

1515

int error;

2015

error_t ret_errno;

1516

2016

int ret;

1517

2017

intmax_t tmpmax;

1518

2018

char *tmp;

1519

2019

int exitcode = EXIT_SUCCESS;

1520

const char *interface = "";

1521

struct ifreq network;

1522

int sd = -1;

1523

bool take_down_interface = false;

1524

uid_t uid;

1525

gid_t gid;

1526

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

1527

bool tempdir_created = false;

2020

char *interfaces_to_take_down = NULL;

2021

size_t interfaces_to_take_down_size = 0;

2022

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

2023

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

2024

char *tempdir = NULL;

1528

2025

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1529

2026

const char *seckey = PATHDIR "/" SECKEY;

1530

2027

const char *pubkey = PATHDIR "/" PUBKEY;

2028

char *interfaces_hooks = NULL;

1531

2029

1532

2030

bool gnutls_initialized = false;

1533

2031

bool gpgme_initialized = false;

1595

2093

.group = 2 },

1596

2094

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

1597

2095

.arg = "SECONDS",

1598

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

2096

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

1599

2097

.group = 2 },

1600

2098

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

1601

2099

.arg = "DIR",

1624

2122

connect_to = arg;

1625

2123

break;

1626

2124

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

1627

interface = arg;

2125

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

2126

arg, (int)',');

2127

if(ret_errno != 0){

2128

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

2129

}

1628

2130

break;

1629

2131

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

1630

2132

seckey = arg;

1673

2175

argp_state_help(state, state->out_stream,

1674

2176

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1675

2177

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

1676

fprintf_plus(state->out_stream,

1677

"Mandos plugin mandos-client: ");

1678

2178

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

1679

2179

exit(argp_err_exit_status);

1680

2180

break;

1709

2209

/* Work around Debian bug #633582:

1710

2210

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

1711

2211

1712

/* Re-raise priviliges */

1713

errno = 0;

1714

ret = seteuid(0);

1715

if(ret == -1){

1716

perror_plus("seteuid");

2212

/* Re-raise privileges */

2213

ret_errno = raise_privileges();

2214

if(ret_errno != 0){

2215

errno = ret_errno;

2216

perror_plus("Failed to raise privileges");

1717

2217

} else {

1718

2218

struct stat st;

1719

2219

1760

2260

}

1761

2261

1762

2262

/* Lower privileges */

1763

errno = 0;

1764

ret = seteuid(uid);

1765

if(ret == -1){

1766

perror_plus("seteuid");

2263

ret_errno = lower_privileges();

2264

if(ret_errno != 0){

2265

errno = ret_errno;

2266

perror_plus("Failed to lower privileges");

2267

}

2268

}

2269

}

2270

2271

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

2272

{

2273

char *interface = NULL;

2274

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

2275

interface))){

2276

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

2277

and if_nametoindex(interface) == 0){

2278

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

2279

fprintf_plus(stderr, "Not using nonexisting interface"

2280

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

2281

}

2282

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

2283

interface = NULL;

1767

2284

}

1768

2285

}

1769

2286

}

1770

2287

1771

2288

/* Run network hooks */

1772

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

1773

goto end;

2289

{

2290

if(mc.interfaces != NULL){

2291

interfaces_hooks = malloc(mc.interfaces_size);

2292

if(interfaces_hooks == NULL){

2293

perror_plus("malloc");

2294

goto end;

2295

}

2296

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

2297

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

2298

}

2299

run_network_hooks("start", interfaces_hooks != NULL ?

2300

interfaces_hooks : "", delay);

1774

2301

}

1775

2302

1776

2303

if(not debug){

1777

2304

avahi_set_log_function(empty_log);

1778

2305

}

1779

2306

1780

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

1781

struct dirent **direntries;

1782

/* First look for interfaces that are up */

1783

ret = scandir(sys_class_net, &direntries, up_interface,

1784

alphasort);

1785

if(ret == 0){

1786

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

1787

free(direntries);

1788

ret = scandir(sys_class_net, &direntries, good_interface,

1789

alphasort);

1790

}

1791

if(ret >= 1){

1792

/* Pick the first interface returned */

1793

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

1794

if(debug){

1795

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

1796

}

1797

if(interface == NULL){

1798

perror_plus("malloc");

1799

free(direntries);

1800

exitcode = EXIT_FAILURE;

1801

goto end;

1802

}

1803

free(direntries);

1804

} else {

1805

free(direntries);

1806

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

1807

exitcode = EXIT_FAILURE;

1808

goto end;

1809

}

1810

}

1811

1812

2307

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

1813

2308

from the signal handler */

1814

2309

/* Initialize the pseudo-RNG for Avahi */

1815

2310

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

1816

mc.simple_poll = avahi_simple_poll_new();

1817

if(mc.simple_poll == NULL){

2311

simple_poll = avahi_simple_poll_new();

2312

if(simple_poll == NULL){

1818

2313

fprintf_plus(stderr,

1819

2314

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

1820

2315

exitcode = EX_UNAVAILABLE;

1884

2379

}

1885

2380

}

1886

2381

1887

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

1888

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

1889

if_index = (AvahiIfIndex) if_nametoindex(interface);

1890

if(if_index == 0){

1891

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

1892

exitcode = EX_UNAVAILABLE;

1893

goto end;

1894

}

1895

1896

if(quit_now){

1897

goto end;

1898

}

1899

1900

/* Re-raise priviliges */

1901

errno = 0;

1902

ret = seteuid(0);

1903

if(ret == -1){

1904

perror_plus("seteuid");

1905

}

1906

1907

#ifdef __linux__

1908

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1909

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

1910

ret = klogctl(8, NULL, 5);

1911

bool restore_loglevel = true;

1912

if(ret == -1){

1913

restore_loglevel = false;

1914

perror_plus("klogctl");

1915

}

1916

#endif /* __linux__ */

1917

1918

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1919

if(sd < 0){

1920

perror_plus("socket");

1921

exitcode = EX_OSERR;

1922

#ifdef __linux__

1923

if(restore_loglevel){

1924

ret = klogctl(7, NULL, 0);

1925

if(ret == -1){

1926

perror_plus("klogctl");

1927

}

1928

}

1929

#endif /* __linux__ */

1930

/* Lower privileges */

1931

errno = 0;

1932

ret = seteuid(uid);

1933

if(ret == -1){

1934

perror_plus("seteuid");

1935

}

1936

goto end;

1937

}

1938

strcpy(network.ifr_name, interface);

1939

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

1940

if(ret == -1){

1941

perror_plus("ioctl SIOCGIFFLAGS");

1942

#ifdef __linux__

1943

if(restore_loglevel){

1944

ret = klogctl(7, NULL, 0);

1945

if(ret == -1){

1946

perror_plus("klogctl");

1947

}

1948

}

1949

#endif /* __linux__ */

1950

exitcode = EX_OSERR;

1951

/* Lower privileges */

1952

errno = 0;

1953

ret = seteuid(uid);

1954

if(ret == -1){

1955

perror_plus("seteuid");

1956

}

1957

goto end;

1958

}

1959

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

1960

network.ifr_flags |= IFF_UP;

1961

take_down_interface = true;

1962

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

1963

if(ret == -1){

1964

take_down_interface = false;

1965

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1966

exitcode = EX_OSERR;

1967

#ifdef __linux__

1968

if(restore_loglevel){

1969

ret = klogctl(7, NULL, 0);

1970

if(ret == -1){

1971

perror_plus("klogctl");

2382

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

2383

if(mc.interfaces == NULL){

2384

struct dirent **direntries = NULL;

2385

/* Look for any good interfaces */

2386

ret = scandir(sys_class_net, &direntries, good_interface,

2387

alphasort);

2388

if(ret >= 1){

2389

/* Add all found interfaces to interfaces list */

2390

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

2391

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

2392

direntries[i]->d_name);

2393

if(ret_errno != 0){

2394

errno = ret_errno;

2395

perror_plus("argz_add");

2396

free(direntries[i]);

2397

continue;

2398

}

2399

if(debug){

2400

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

2401

direntries[i]->d_name);

2402

}

2403

free(direntries[i]);

2404

}

2405

free(direntries);

2406

} else {

2407

if(ret == 0){

2408

free(direntries);

2409

}

2410

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

2411

exitcode = EXIT_FAILURE;

2412

goto end;

2413

}

2414

}

2415

2416

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

2417

{

2418

char *interface = NULL;

2419

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

2420

interface))){

2421

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

2422

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

2423

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

2424

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

2425

interface);

2426

interface = NULL;

2427

while((interface = argz_next(mc.interfaces,

2428

mc.interfaces_size, interface))){

2429

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

2430

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

2431

interface);

2432

interface = NULL;

1972

2433

}

1973

2434

}

1974

#endif /* __linux__ */

1975

/* Lower privileges */

1976

errno = 0;

1977

ret = seteuid(uid);

1978

if(ret == -1){

1979

perror_plus("seteuid");

1980

}

1981

goto end;

1982

}

1983

}

1984

/* Sleep checking until interface is running.

1985

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

1986

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

1987

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

1988

if(ret == -1){

1989

perror_plus("ioctl SIOCGIFFLAGS");

1990

} else if(network.ifr_flags & IFF_RUNNING){

1991

2435

break;

1992

2436

}

1993

struct timespec sleeptime = { .tv_nsec = 250000000 };

1994

ret = nanosleep(&sleeptime, NULL);

1995

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

1996

perror_plus("nanosleep");

1997

}

1998

}

1999

if(not take_down_interface){

2000

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

2001

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

2002

if(ret == -1){

2003

perror_plus("close");

2004

}

2005

}

2006

#ifdef __linux__

2007

if(restore_loglevel){

2008

/* Restores kernel loglevel to default */

2009

ret = klogctl(7, NULL, 0);

2010

if(ret == -1){

2011

perror_plus("klogctl");

2012

}

2013

}

2014

#endif /* __linux__ */

2015

/* Lower privileges */

2016

errno = 0;

2017

/* Lower privileges */

2018

ret = seteuid(uid);

2019

if(ret == -1){

2020

perror_plus("seteuid");

2021

}

2437

bool interface_was_up = interface_is_up(interface);

2438

errno = bring_up_interface(interface, delay);

2439

if(not interface_was_up){

2440

if(errno != 0){

2441

perror_plus("Failed to bring up interface");

2442

} else {

2443

errno = argz_add(&interfaces_to_take_down,

2444

&interfaces_to_take_down_size,

2445

interface);

2446

if(errno != 0){

2447

perror_plus("argz_add");

2448

}

2449

}

2450

}

2451

}

2452

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

2453

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

2454

}

2455

}

2456

2457

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

2458

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

2459

if(debug){

2460

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

2461

mc.interfaces);

2462

}

2463

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

2022

2464

}

2023

2465

2024

2466

if(quit_now){

2025

2467

goto end;

2026

2468

}

2027

2469

2028

ret = init_gnutls_global(pubkey, seckey);

2470

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

2029

2471

if(ret == -1){

2030

2472

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

2031

2473

exitcode = EX_UNAVAILABLE;

2038

2480

goto end;

2039

2481

}

2040

2482

2041

if(mkdtemp(tempdir) == NULL){

2483

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

2484

tempdir = mkdtemp(run_tempdir);

2485

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

2486

if(debug){

2487

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

2488

run_tempdir, old_tempdir);

2489

}

2490

tempdir = mkdtemp(old_tempdir);

2491

}

2492

if(tempdir == NULL){

2042

2493

perror_plus("mkdtemp");

2043

2494

goto end;

2044

2495

}

2045

tempdir_created = true;

2046

2496

2047

2497

if(quit_now){

2048

2498

goto end;

2049

2499

}

2050

2500

2051

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

2501

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

2052

2502

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

2053

2503

exitcode = EX_UNAVAILABLE;

2054

2504

goto end;

2064

2514

/* Connect directly, do not use Zeroconf */

2065

2515

/* (Mainly meant for debugging) */

2066

2516

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

2517

2067

2518

if(address == NULL){

2068

2519

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

2069

2520

exitcode = EX_USAGE;

2074

2525

goto end;

2075

2526

}

2076

2527

2077

uint16_t port;

2528

in_port_t port;

2078

2529

errno = 0;

2079

2530

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

2080

2531

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

2081

or tmpmax != (uint16_t)tmpmax){

2532

or tmpmax != (in_port_t)tmpmax){

2082

2533

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

2083

2534

exitcode = EX_USAGE;

2084

2535

goto end;

2085

2536

}

2086

2537

2087

2538

if(quit_now){

2088

2539

goto end;

2089

2540

}

2090

2541

2091

port = (uint16_t)tmpmax;

2542

port = (in_port_t)tmpmax;

2092

2543

*address = '\0';

2093

2544

/* Colon in address indicates IPv6 */

2094

2545

int af;

2110

2561

}

2111

2562

2112

2563

while(not quit_now){

2113

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

2564

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

2565

&mc);

2114

2566

if(quit_now or ret == 0){

2115

2567

break;

2116

2568

}

2118

2570

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

2119

2571

(int)retry_interval);

2120

2572

}

2121

sleep((int)retry_interval);

2573

sleep((unsigned int)retry_interval);

2122

2574

}

2123

2575

2124

if (not quit_now){

2576

if(not quit_now){

2125

2577

exitcode = EXIT_SUCCESS;

2126

2578

}

2127

2579

2142

2594

config.publish_domain = 0;

2143

2595

2144

2596

/* Allocate a new server */

2145

mc.server = avahi_server_new(avahi_simple_poll_get

2146

(mc.simple_poll), &config, NULL,

2147

NULL, &error);

2597

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2598

&config, NULL, NULL, &ret_errno);

2148

2599

2149

2600

/* Free the Avahi configuration data */

2150

2601

avahi_server_config_free(&config);

2153

2604

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

2154

2605

if(mc.server == NULL){

2155

2606

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

2156

avahi_strerror(error));

2607

avahi_strerror(ret_errno));

2157

2608

exitcode = EX_UNAVAILABLE;

2158

2609

goto end;

2159

2610

}

2165

2616

/* Create the Avahi service browser */

2166

2617

sb = avahi_s_service_browser_new(mc.server, if_index,

2167

2618

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2168

NULL, 0, browse_callback, NULL);

2619

NULL, 0, browse_callback,

2620

(void *)&mc);

2169

2621

if(sb == NULL){

2170

2622

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

2171

2623

avahi_strerror(avahi_server_errno(mc.server)));

2182

2634

if(debug){

2183

2635

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

2184

2636

}

2185

2186

ret = avahi_loop_with_timeout(mc.simple_poll,

2187

(int)(retry_interval * 1000));

2637

2638

ret = avahi_loop_with_timeout(simple_poll,

2639

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

2188

2640

if(debug){

2189

2641

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

2190

2642

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

2197

2649

}

2198

2650

2199

2651

/* Cleanup things */

2652

free(mc.interfaces);

2653

2200

2654

if(sb != NULL)

2201

2655

avahi_s_service_browser_free(sb);

2202

2656

2203

2657

if(mc.server != NULL)

2204

2658

avahi_server_free(mc.server);

2205

2659

2206

if(mc.simple_poll != NULL)

2207

avahi_simple_poll_free(mc.simple_poll);

2660

if(simple_poll != NULL)

2661

avahi_simple_poll_free(simple_poll);

2208

2662

2209

2663

if(gnutls_initialized){

2210

2664

gnutls_certificate_free_credentials(mc.cred);

2222

2676

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

2223

2677

while(mc.current_server != NULL){

2224

2678

server *next = mc.current_server->next;

2679

#ifdef __GNUC__

2680

#pragma GCC diagnostic push

2681

#pragma GCC diagnostic ignored "-Wcast-qual"

2682

#endif

2683

free((char *)(mc.current_server->ip));

2684

#ifdef __GNUC__

2685

#pragma GCC diagnostic pop

2686

#endif

2225

2687

free(mc.current_server);

2226

2688

mc.current_server = next;

2227

2689

}

2228

2690

}

2229

2691

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Re-raise priviliges */

2692

/* Re-raise privileges */

2234

2693

{

2235

errno = 0;

2236

ret = seteuid(0);

2237

if(ret == -1){

2238

perror_plus("seteuid");

2694

ret_errno = raise_privileges();

2695

if(ret_errno != 0){

2696

errno = ret_errno;

2697

perror_plus("Failed to raise privileges");

2698

} else {

2699

2700

/* Run network hooks */

2701

run_network_hooks("stop", interfaces_hooks != NULL ?

2702

interfaces_hooks : "", delay);

2703

2704

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

2705

{

2706

char *interface = NULL;

2707

while((interface=argz_next(interfaces_to_take_down,

2708

interfaces_to_take_down_size,

2709

interface))){

2710

ret_errno = take_down_interface(interface);

2711

if(ret_errno != 0){

2712

errno = ret_errno;

2713

perror_plus("Failed to take down interface");

2714

}

2715

}

2716

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

2717

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

2718

" down\n");

2719

}

2720

}

2239

2721

}

2240

2722

2241

/* Take down the network interface */

2242

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

2243

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

2244

if(ret == -1){

2245

perror_plus("ioctl SIOCGIFFLAGS");

2246

} else if(network.ifr_flags & IFF_UP){

2247

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

2248

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

2249

if(ret == -1){

2250

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2251

}

2252

}

2253

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

2254

if(ret == -1){

2255

perror_plus("close");

2256

}

2723

ret_errno = lower_privileges_permanently();

2724

if(ret_errno != 0){

2725

errno = ret_errno;

2726

perror_plus("Failed to lower privileges permanently");

2257

2727

}

2258

2728

}

2259

/* Lower privileges permanently */

2260

errno = 0;

2261

ret = setuid(uid);

2262

if(ret == -1){

2263

perror_plus("setuid");

2264

}

2729

2730

free(interfaces_to_take_down);

2731

free(interfaces_hooks);

2265

2732

2266

2733

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

2267

if(tempdir_created){

2734

if(tempdir != NULL){

2268

2735

struct dirent **direntries = NULL;

2269

struct dirent *direntry = NULL;

2270

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

2271

alphasort);

2272

if (numentries > 0){

2273

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

2274

direntry = direntries[i];

2275

char *fullname = NULL;

2276

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

2277

direntry->d_name);

2278

if(ret < 0){

2279

perror_plus("asprintf");

2280

continue;

2281

}

2282

ret = remove(fullname);

2283

if(ret == -1){

2284

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

2285

strerror(errno));

2286

}

2287

free(fullname);

2736

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |

2737

O_NOFOLLOW));

2738

if(tempdir_fd == -1){

2739

perror_plus("open");

2740

} else {

2741

#ifdef __GLIBC__

2742

#if __GLIBC_PREREQ(2, 15)

2743

int numentries = scandirat(tempdir_fd, ".", &direntries,

2744

notdotentries, alphasort);

2745

#else /* not __GLIBC_PREREQ(2, 15) */

2746

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

2747

alphasort);

2748

#endif /* not __GLIBC_PREREQ(2, 15) */

2749

#else /* not __GLIBC__ */

2750

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

2751

alphasort);

2752

#endif /* not __GLIBC__ */

2753

if(numentries >= 0){

2754

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

2755

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2756

if(ret == -1){

2757

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2758

" \"%s\", 0): %s\n", tempdir,

2759

direntries[i]->d_name, strerror(errno));

2760

}

2761

free(direntries[i]);

2762

}

2763

2764

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

2765

free(direntries);

2766

if(numentries == -1){

2767

perror_plus("scandir");

2768

}

2769

ret = rmdir(tempdir);

2770

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

2771

perror_plus("rmdir");

2772

}

2288

2773

}

2289

}

2290

2291

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

2292

free(direntries);

2293

if (numentries == -1){

2294

perror_plus("scandir");

2295

}

2296

ret = rmdir(tempdir);

2297

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

2298

perror_plus("rmdir");

2774

TEMP_FAILURE_RETRY(close(tempdir_fd));

2299

2775

}

2300

2776

}

2301

2777