/mandos/trunk : revision 533

9

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

10

*

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* Everything else is

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13

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 /* not _LARGEFILE_SOURCE */

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#endif

36

#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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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() */

44

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

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stdout, ferror(), remove() */

44

#include <stdint.h> /* uint16_t, uint32_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() */

55

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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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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61

*/

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

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strtoimax() */

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

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

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program_invocation_short_name */

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

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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unlinkat() */

78

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

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

77

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

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

80

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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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88

#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() */

98

91

99

92

#ifdef __linux__

100

93

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

142

135

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

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136

char *connect_to = NULL;

144

137

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

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gid_t gid = 65534;

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138

149

139

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

150

140

typedef struct server{

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141

const char *ip;

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in_port_t port;

142

uint16_t port;

153

143

AvahiIfIndex if_index;

154

144

int af;

155

145

struct timespec last_seen;

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149

160

150

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

161

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

162

153

AvahiServer *server;

163

154

gnutls_certificate_credentials_t cred;

164

155

unsigned int dh_bits;

166

157

const char *priority;

167

158

gpgme_ctx_t ctx;

168

159

server *current_server;

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char *interfaces;

170

size_t interfaces_size;

171

160

} mandos_context;

172

161

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

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 };

175

167

176

168

sig_atomic_t quit_now = 0;

177

169

int signal_received = 0;

178

170

179

171

/* Function to use when printing errors */

180

172

void perror_plus(const char *print_text){

181

int e = errno;

182

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

183

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program_invocation_short_name);

184

errno = e;

185

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perror(print_text);

186

176

}

187

177

188

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

178

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

189

179

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

190

180

va_list ap;

191

181

va_start (ap, format);

192

182

193

183

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

194

184

program_invocation_short_name));

195

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

185

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

196

186

}

197

187

198

188

/*

200

190

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

201

191

* "buffer_length" is how much is already used.

202

192

*/

203

__attribute__((nonnull, warn_unused_result))

204

193

size_t incbuffer(char **buffer, size_t buffer_length,

205

194

size_t buffer_capacity){

206

195

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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;

196

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

197

if(buffer == NULL){

213

198

return 0;

214

199

}

215

*buffer = new_buf;

216

200

buffer_capacity += BUFFER_SIZE;

217

201

}

218

202

return buffer_capacity;

219

203

}

220

204

221

205

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

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){

206

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

207

int af){

225

208

int ret;

226

209

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

227

210

if(new_server == NULL){

234

217

.af = af };

235

218

if(new_server->ip == NULL){

236

219

perror_plus("strdup");

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

220

return false;

253

221

}

254

222

/* Special case of first server */

255

if(*current_server == NULL){

223

if (mc.current_server == NULL){

256

224

new_server->next = new_server;

257

225

new_server->prev = new_server;

258

*current_server = new_server;

226

mc.current_server = new_server;

227

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

259

228

} else {

260

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

261

new_server->next = *current_server;

262

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

229

new_server->next = mc.current_server;

230

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

263

231

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

232

mc.current_server->prev = new_server;

233

}

234

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

235

if(ret == -1){

236

perror_plus("clock_gettime");

237

return false;

265

238

}

266

239

return true;

267

240

}

269

242

/*

270

243

* Initialize GPGME.

271

244

*/

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){

245

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

246

const char *tempdir){

277

247

gpgme_error_t rc;

278

248

gpgme_engine_info_t engine_info;

279

249

250

280

251

/*

281

252

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

282

253

*/

283

bool import_key(const char * const filename){

254

bool import_key(const char *filename){

284

255

int ret;

285

256

int fd;

286

257

gpgme_data_t pgp_data;

298

269

return false;

299

270

}

300

271

301

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

272

rc = gpgme_op_import(mc.ctx, pgp_data);

302

273

if(rc != GPG_ERR_NO_ERROR){

303

274

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

304

275

gpgme_strsource(rc), gpgme_strerror(rc));

348

319

}

349

320

350

321

/* Create new GPGME "context" */

351

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

322

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

352

323

if(rc != GPG_ERR_NO_ERROR){

353

324

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

354

325

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

367

338

* Decrypt OpenPGP data.

368

339

* Returns -1 on error

369

340

*/

370

__attribute__((nonnull, warn_unused_result))

371

341

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

342

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

343

char **plaintext){

375

344

gpgme_data_t dh_crypto, dh_plain;

376

345

gpgme_error_t rc;

377

346

ssize_t ret;

403

372

404

373

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

405

374

data buffer */

406

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

375

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

407

376

if(rc != GPG_ERR_NO_ERROR){

408

377

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

409

378

gpgme_strsource(rc), gpgme_strerror(rc));

410

379

plaintext_length = -1;

411

380

if(debug){

412

381

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

382

result = gpgme_op_decrypt_result(mc.ctx);

414

383

if(result == NULL){

415

384

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

416

385

} else {

493

462

return plaintext_length;

494

463

}

495

464

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);

465

static const char * safer_gnutls_strerror(int value){

466

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

467

-Wunreachable-code */

468

if(ret == NULL)

469

ret = "(unknown)";

470

return ret;

507

471

}

508

472

509

473

/* GnuTLS log function callback */

510

__attribute__((nonnull))

511

474

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

512

475

const char* string){

513

476

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

514

477

}

515

478

516

__attribute__((nonnull, warn_unused_result))

517

479

static int init_gnutls_global(const char *pubkeyfilename,

518

const char *seckeyfilename,

519

mandos_context *mc){

480

const char *seckeyfilename){

520

481

int ret;

521

unsigned int uret;

522

482

523

483

if(debug){

524

484

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

540

500

}

541

501

542

502

/* OpenPGP credentials */

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

503

ret = gnutls_certificate_allocate_credentials(&mc.cred);

544

504

if(ret != GNUTLS_E_SUCCESS){

545

505

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

546

506

safer_gnutls_strerror(ret));

556

516

}

557

517

558

518

ret = gnutls_certificate_set_openpgp_key_file

559

(mc->cred, pubkeyfilename, seckeyfilename,

519

(mc.cred, pubkeyfilename, seckeyfilename,

560

520

GNUTLS_OPENPGP_FMT_BASE64);

561

521

if(ret != GNUTLS_E_SUCCESS){

562

522

fprintf_plus(stderr,

568

528

}

569

529

570

530

/* GnuTLS server initialization */

571

ret = gnutls_dh_params_init(&mc->dh_params);

531

ret = gnutls_dh_params_init(&mc.dh_params);

572

532

if(ret != GNUTLS_E_SUCCESS){

573

533

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

574

534

" initialization: %s\n",

575

535

safer_gnutls_strerror(ret));

576

536

goto globalfail;

577

537

}

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

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

680

539

if(ret != GNUTLS_E_SUCCESS){

681

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

682

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

540

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

541

safer_gnutls_strerror(ret));

683

542

goto globalfail;

684

543

}

685

544

686

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

545

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

687

546

688

547

return 0;

689

548

690

549

globalfail:

691

550

692

gnutls_certificate_free_credentials(mc->cred);

551

gnutls_certificate_free_credentials(mc.cred);

693

552

gnutls_global_deinit();

694

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_dh_params_deinit(mc.dh_params);

695

554

return -1;

696

555

}

697

556

698

__attribute__((nonnull, warn_unused_result))

699

static int init_gnutls_session(gnutls_session_t *session,

700

mandos_context *mc){

557

static int init_gnutls_session(gnutls_session_t *session){

701

558

int ret;

702

559

/* GnuTLS session creation */

703

560

do {

715

572

{

716

573

const char *err;

717

574

do {

718

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

575

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

719

576

if(quit_now){

720

577

gnutls_deinit(*session);

721

578

return -1;

732

589

733

590

do {

734

591

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

735

mc->cred);

592

mc.cred);

736

593

if(quit_now){

737

594

gnutls_deinit(*session);

738

595

return -1;

748

605

/* ignore client certificate if any. */

749

606

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

750

607

751

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

608

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

752

609

753

610

return 0;

754

611

}

758

615

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

759

616

760

617

/* Called when a Mandos server is found */

761

__attribute__((nonnull, warn_unused_result))

762

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

618

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

763

619

AvahiIfIndex if_index,

764

int af, mandos_context *mc){

620

int af){

765

621

int ret, tcp_sd = -1;

766

622

ssize_t sret;

767

struct sockaddr_storage to;

623

union {

624

struct sockaddr_in in;

625

struct sockaddr_in6 in6;

626

} to;

768

627

char *buffer = NULL;

769

628

char *decrypted_buffer = NULL;

770

629

size_t buffer_length = 0;

794

653

return -1;

795

654

}

796

655

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

ret = init_gnutls_session(&session);

830

657

if(ret != 0){

831

658

return -1;

832

659

}

833

660

834

661

if(debug){

835

662

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

836

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

663

PRIu16 "\n", ip, port);

837

664

}

838

665

839

666

tcp_sd = socket(pf, SOCK_STREAM, 0);

851

678

852

679

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

853

680

if(af == AF_INET6){

854

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

855

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

681

to.in6.sin6_family = (sa_family_t)af;

682

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

856

683

} else { /* IPv4 */

857

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

858

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

684

to.in.sin_family = (sa_family_t)af;

685

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

859

686

}

860

687

if(ret < 0 ){

861

688

int e = errno;

870

697

goto mandos_end;

871

698

}

872

699

if(af == AF_INET6){

873

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

874

if(IN6_IS_ADDR_LINKLOCAL

875

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

700

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

701

-Wconversion and

702

-Wunreachable-code */

703

704

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

705

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

706

-Wunreachable-code*/

876

707

if(if_index == AVAHI_IF_UNSPEC){

877

708

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

878

709

" incomplete without a network interface\n");

880

711

goto mandos_end;

881

712

}

882

713

/* Set the network interface number as scope */

883

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

714

to.in6.sin6_scope_id = (uint32_t)if_index;

884

715

}

885

716

} else {

886

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

717

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

718

-Wconversion and

719

-Wunreachable-code */

887

720

}

888

721

889

722

if(quit_now){

897

730

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

898

731

perror_plus("if_indextoname");

899

732

} else {

900

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

901

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

733

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

734

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

902

735

}

903

736

} else {

904

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

905

ip, (uintmax_t)port);

737

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

738

ip, port);

906

739

}

907

740

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

908

741

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

742

const char *pcret;

909

743

if(af == AF_INET6){

910

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

911

sizeof(struct sockaddr_in6),

912

addrstr, sizeof(addrstr), NULL, 0,

913

NI_NUMERICHOST);

744

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

745

sizeof(addrstr));

914

746

} else {

915

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

916

sizeof(struct sockaddr_in),

917

addrstr, sizeof(addrstr), NULL, 0,

918

NI_NUMERICHOST);

747

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

748

sizeof(addrstr));

919

749

}

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);

750

if(pcret == NULL){

751

perror_plus("inet_ntop");

752

} else {

753

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

754

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

755

}

926

756

}

927

757

}

928

758

932

762

}

933

763

934

764

if(af == AF_INET6){

935

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

936

sizeof(struct sockaddr_in6));

765

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

937

766

} else {

938

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

939

sizeof(struct sockaddr_in));

767

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

940

768

}

941

769

if(ret < 0){

942

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

770

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

943

771

int e = errno;

944

772

perror_plus("connect");

945

773

errno = e;

991

819

goto mandos_end;

992

820

}

993

821

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);

822

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

823

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

999

824

1000

825

if(quit_now){

1001

826

errno = EINTR;

1106

931

if(buffer_length > 0){

1107

932

ssize_t decrypted_buffer_size;

1108

933

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1109

&decrypted_buffer, mc);

934

&decrypted_buffer);

1110

935

if(decrypted_buffer_size >= 0){

1111

936

1112

937

written = 0;

1160

985

return retval;

1161

986

}

1162

987

1163

__attribute__((nonnull))

1164

988

static void resolve_callback(AvahiSServiceResolver *r,

1165

989

AvahiIfIndex interface,

1166

990

AvahiProtocol proto,

1174

998

AVAHI_GCC_UNUSED AvahiStringList *txt,

1175

999

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1176

1000

flags,

1177

void *mc){

1178

if(r == NULL){

1179

return;

1180

}

1001

AVAHI_GCC_UNUSED void* userdata){

1002

assert(r);

1181

1003

1182

1004

/* Called whenever a service has been resolved successfully or

1183

1005

timed out */

1184

1006

1185

1007

if(quit_now){

1186

avahi_s_service_resolver_free(r);

1187

1008

return;

1188

1009

}

1189

1010

1193

1014

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

1194

1015

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

1195

1016

domain,

1196

avahi_strerror(avahi_server_errno

1197

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

1017

avahi_strerror(avahi_server_errno(mc.server)));

1198

1018

break;

1199

1019

1200

1020

case AVAHI_RESOLVER_FOUND:

1206

1026

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

1207

1027

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

1208

1028

}

1209

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

1210

interface,

1211

avahi_proto_to_af(proto),

1212

mc);

1029

int ret = start_mandos_communication(ip, port, interface,

1030

avahi_proto_to_af(proto));

1213

1031

if(ret == 0){

1214

avahi_simple_poll_quit(simple_poll);

1032

avahi_simple_poll_quit(mc.simple_poll);

1215

1033

} else {

1216

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

1217

avahi_proto_to_af(proto),

1218

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

1034

if(not add_server(ip, port, interface,

1035

avahi_proto_to_af(proto))){

1219

1036

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

1220

1037

" list\n", name);

1221

1038

}

1234

1051

const char *domain,

1235

1052

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1236

1053

flags,

1237

void *mc){

1238

if(b == NULL){

1239

return;

1240

}

1054

AVAHI_GCC_UNUSED void* userdata){

1055

assert(b);

1241

1056

1242

1057

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

1243

1058

is removed from the LAN */

1251

1066

case AVAHI_BROWSER_FAILURE:

1252

1067

1253

1068

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

1254

avahi_strerror(avahi_server_errno

1255

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

1256

avahi_simple_poll_quit(simple_poll);

1069

avahi_strerror(avahi_server_errno(mc.server)));

1070

avahi_simple_poll_quit(mc.simple_poll);

1257

1071

return;

1258

1072

1259

1073

case AVAHI_BROWSER_NEW:

1262

1076

the callback function is called the Avahi server will free the

1263

1077

resolver for us. */

1264

1078

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)

1079

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

1080

name, type, domain, protocol, 0,

1081

resolve_callback, NULL) == NULL)

1269

1082

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

1270

1083

" %s\n", name,

1271

avahi_strerror(avahi_server_errno

1272

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

1084

avahi_strerror(avahi_server_errno(mc.server)));

1273

1085

break;

1274

1086

1275

1087

case AVAHI_BROWSER_REMOVE:

1294

1106

signal_received = sig;

1295

1107

int old_errno = errno;

1296

1108

/* set main loop to exit */

1297

if(simple_poll != NULL){

1298

avahi_simple_poll_quit(simple_poll);

1109

if(mc.simple_poll != NULL){

1110

avahi_simple_poll_quit(mc.simple_poll);

1299

1111

}

1300

1112

errno = old_errno;

1301

1113

}

1302

1114

1303

__attribute__((nonnull, warn_unused_result))

1304

1115

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

1305

1116

int ret;

1306

error_t ret_errno;

1307

1117

1308

1118

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

1309

1119

if(s < 0){

1310

ret_errno = errno;

1311

1120

perror_plus("socket");

1312

errno = ret_errno;

1313

1121

return false;

1314

1122

}

1315

1123

strcpy(ifr->ifr_name, ifname);

1316

1124

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1317

1125

if(ret == -1){

1318

1126

if(debug){

1319

ret_errno = errno;

1320

1127

perror_plus("ioctl SIOCGIFFLAGS");

1321

errno = ret_errno;

1322

1128

}

1323

1129

return false;

1324

1130

}

1325

1131

return true;

1326

1132

}

1327

1133

1328

__attribute__((nonnull, warn_unused_result))

1329

1134

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

1330

1135

1331

1136

/* Reject the loopback device */

1373

1178

* corresponds to an acceptable network device.

1374

1179

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

1375

1180

*/

1376

__attribute__((nonnull, warn_unused_result))

1377

1181

int good_interface(const struct dirent *if_entry){

1378

1182

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

1379

1183

return 0;

1395

1199

}

1396

1200

1397

1201

/*

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))

1202

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

1203

* corresponds to an acceptable network device which is up.

1204

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

1205

*/

1206

int up_interface(const struct dirent *if_entry){

1207

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

1208

return 0;

1209

}

1210

1211

struct ifreq ifr;

1212

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

1213

if(debug){

1214

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

1215

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

1216

}

1217

return 0;

1218

}

1219

1220

/* Reject down interfaces */

1221

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

1222

if(debug){

1223

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

1224

if_entry->d_name);

1225

}

1226

return 0;

1227

}

1228

1229

/* Reject non-running interfaces */

1230

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

1231

if(debug){

1232

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

1233

if_entry->d_name);

1234

}

1235

return 0;

1236

}

1237

1238

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

1239

return 0;

1240

}

1241

return 1;

1242

}

1243

1432

1244

int notdotentries(const struct dirent *direntry){

1433

1245

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

1434

1246

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

1441

1253

}

1442

1254

1443

1255

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

1444

__attribute__((nonnull, warn_unused_result))

1445

1256

int runnable_hook(const struct dirent *direntry){

1446

1257

int ret;

1447

1258

size_t sret;

1455

1266

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

1456

1267

"abcdefghijklmnopqrstuvwxyz"

1457

1268

"0123456789"

1458

"_.-");

1269

"_-");

1459

1270

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

1460

1271

/* Contains non-allowed characters */

1461

1272

if(debug){

1465

1276

return 0;

1466

1277

}

1467

1278

1468

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

1279

char *fullname = NULL;

1280

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

1281

if(ret < 0){

1282

perror_plus("asprintf");

1283

return 0;

1284

}

1285

1286

ret = stat(fullname, &st);

1469

1287

if(ret == -1){

1470

1288

if(debug){

1471

1289

perror_plus("Could not stat hook");

1495

1313

return 1;

1496

1314

}

1497

1315

1498

__attribute__((nonnull, warn_unused_result))

1499

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1500

mandos_context *mc){

1316

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1501

1317

int ret;

1502

1318

struct timespec now;

1503

1319

struct timespec waited_time;

1504

1320

intmax_t block_time;

1505

1321

1506

1322

while(true){

1507

if(mc->current_server == NULL){

1508

if(debug){

1323

if(mc.current_server == NULL){

1324

if (debug){

1509

1325

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

1510

1326

" No timeout!\n");

1511

1327

}

1512

1328

ret = avahi_simple_poll_iterate(s, -1);

1513

1329

} else {

1514

if(debug){

1330

if (debug){

1515

1331

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

1516

1332

" it, or wait\n");

1517

1333

}

1524

1340

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

1525

1341

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

1526

1342

waited_time.tv_sec = (now.tv_sec

1527

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

1343

- mc.current_server->last_seen.tv_sec);

1528

1344

waited_time.tv_nsec = (now.tv_nsec

1529

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

1345

- mc.current_server->last_seen.tv_nsec);

1530

1346

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

1531

1347

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

1532

1348

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

1534

1350

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

1535

1351

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

1536

1352

1537

if(debug){

1353

if (debug){

1538

1354

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

1539

1355

block_time);

1540

1356

}

1541

1357

1542

1358

if(block_time <= 0){

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

ret = start_mandos_communication(mc.current_server->ip,

1360

mc.current_server->port,

1361

mc.current_server->if_index,

1362

mc.current_server->af);

1547

1363

if(ret == 0){

1548

avahi_simple_poll_quit(s);

1364

avahi_simple_poll_quit(mc.simple_poll);

1549

1365

return 0;

1550

1366

}

1551

1367

ret = clock_gettime(CLOCK_MONOTONIC,

1552

&mc->current_server->last_seen);

1368

&mc.current_server->last_seen);

1553

1369

if(ret == -1){

1554

1370

perror_plus("clock_gettime");

1555

1371

return -1;

1556

1372

}

1557

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

1373

mc.current_server = mc.current_server->next;

1558

1374

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

1559

1375

servers, but don't block */

1560

1376

}

1562

1378

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

1563

1379

}

1564

1380

if(ret != 0){

1565

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

1381

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

1566

1382

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

1567

1383

}

1568

1384

}

1569

1385

}

1570

1386

}

1571

1387

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,

1388

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

1626

1389

const float delay){

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__ */

1390

struct dirent **direntries;

1391

struct dirent *direntry;

1392

int ret;

1393

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

1394

alphasort);

1654

1395

if(numhooks == -1){

1655

1396

perror_plus("scandir");

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){

1397

} else {

1398

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

1399

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

1400

direntry = direntries[i];

1401

char *fullname = NULL;

1402

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

1403

if(ret < 0){

1728

1404

perror_plus("asprintf");

1729

_exit(EX_OSERR);

1730

}

1731

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

1732

if(ret == -1){

1405

continue;

1406

}

1407

if(debug){

1408

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

1409

direntry->d_name);

1410

}

1411

pid_t hook_pid = fork();

1412

if(hook_pid == 0){

1413

/* Child */

1414

/* Raise privileges */

1415

errno = 0;

1416

ret = seteuid(0);

1417

if(ret == -1){

1418

perror_plus("seteuid");

1419

}

1420

/* Raise privileges even more */

1421

errno = 0;

1422

ret = setuid(0);

1423

if(ret == -1){

1424

perror_plus("setuid");

1425

}

1426

/* Set group */

1427

errno = 0;

1428

ret = setgid(0);

1429

if(ret == -1){

1430

perror_plus("setgid");

1431

}

1432

/* Reset supplementary groups */

1433

errno = 0;

1434

ret = setgroups(0, NULL);

1435

if(ret == -1){

1436

perror_plus("setgroups");

1437

}

1438

dup2(devnull, STDIN_FILENO);

1439

close(devnull);

1440

dup2(STDERR_FILENO, STDOUT_FILENO);

1441

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

1442

if(ret == -1){

1443

perror_plus("setenv");

1444

_exit(EX_OSERR);

1445

}

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

char *delaystring;

1462

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

1463

if(ret == -1){

1464

perror_plus("asprintf");

1465

_exit(EX_OSERR);

1466

}

1467

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

1468

if(ret == -1){

1469

free(delaystring);

1470

perror_plus("setenv");

1471

_exit(EX_OSERR);

1472

}

1733

1473

free(delaystring);

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;

1474

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

1475

perror_plus("execl");

1476

_exit(EXIT_FAILURE);

1477

}

1478

} else {

1479

int status;

1480

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

1481

perror_plus("waitpid");

1482

free(fullname);

1483

continue;

1484

}

1485

if(WIFEXITED(status)){

1486

if(WEXITSTATUS(status) != 0){

1487

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

1488

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

1489

WEXITSTATUS(status));

1490

free(fullname);

1491

continue;

1492

}

1493

} else if(WIFSIGNALED(status)){

1494

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

1495

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

1496

WTERMSIG(status));

1497

free(fullname);

1498

continue;

1499

} else {

1500

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

1501

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

1502

free(fullname);

1503

continue;

1504

}

1505

}

1506

free(fullname);

1507

if(debug){

1508

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

1509

direntry->d_name);

1510

}

1511

}

1512

close(devnull);

1513

}

1514

return true;

2007

1515

}

2008

1516

2009

1517

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 };

2014

1518

AvahiSServiceBrowser *sb = NULL;

2015

error_t ret_errno;

1519

int error;

2016

1520

int ret;

2017

1521

intmax_t tmpmax;

2018

1522

char *tmp;

2019

1523

int exitcode = EXIT_SUCCESS;

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;

1524

const char *interface = "";

1525

struct ifreq network;

1526

int sd = -1;

1527

bool take_down_interface = false;

1528

uid_t uid;

1529

gid_t gid;

1530

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

1531

bool tempdir_created = false;

2025

1532

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2026

1533

const char *seckey = PATHDIR "/" SECKEY;

2027

1534

const char *pubkey = PATHDIR "/" PUBKEY;

2028

char *interfaces_hooks = NULL;

2029

1535

2030

1536

bool gnutls_initialized = false;

2031

1537

bool gpgme_initialized = false;

2093

1599

.group = 2 },

2094

1600

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

2095

1601

.arg = "SECONDS",

2096

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

1602

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

2097

1603

.group = 2 },

2098

1604

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

2099

1605

.arg = "DIR",

2122

1628

connect_to = arg;

2123

1629

break;

2124

1630

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

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

}

1631

interface = arg;

2130

1632

break;

2131

1633

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

2132

1634

seckey = arg;

2209

1711

/* Work around Debian bug #633582:

2210

1712

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

2211

1713

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");

1714

/* Re-raise priviliges */

1715

errno = 0;

1716

ret = seteuid(0);

1717

if(ret == -1){

1718

perror_plus("seteuid");

2217

1719

} else {

2218

1720

struct stat st;

2219

1721

2260

1762

}

2261

1763

2262

1764

/* Lower privileges */

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;

1765

errno = 0;

1766

ret = seteuid(uid);

1767

if(ret == -1){

1768

perror_plus("seteuid");

2284

1769

}

2285

1770

}

2286

1771

}

2287

1772

2288

1773

/* Run network hooks */

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

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

1775

goto end;

2301

1776

}

2302

1777

2303

1778

if(not debug){

2304

1779

avahi_set_log_function(empty_log);

2305

1780

}

2306

1781

1782

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

1783

struct dirent **direntries;

1784

/* First look for interfaces that are up */

1785

ret = scandir(sys_class_net, &direntries, up_interface,

1786

alphasort);

1787

if(ret == 0){

1788

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

1789

free(direntries);

1790

ret = scandir(sys_class_net, &direntries, good_interface,

1791

alphasort);

1792

}

1793

if(ret >= 1){

1794

/* Pick the first interface returned */

1795

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

1796

if(debug){

1797

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

1798

}

1799

if(interface == NULL){

1800

perror_plus("malloc");

1801

free(direntries);

1802

exitcode = EXIT_FAILURE;

1803

goto end;

1804

}

1805

free(direntries);

1806

} else {

1807

free(direntries);

1808

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

1809

exitcode = EXIT_FAILURE;

1810

goto end;

1811

}

1812

}

1813

2307

1814

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

2308

1815

from the signal handler */

2309

1816

/* Initialize the pseudo-RNG for Avahi */

2310

1817

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

2311

simple_poll = avahi_simple_poll_new();

2312

if(simple_poll == NULL){

1818

mc.simple_poll = avahi_simple_poll_new();

1819

if(mc.simple_poll == NULL){

2313

1820

fprintf_plus(stderr,

2314

1821

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

2315

1822

exitcode = EX_UNAVAILABLE;

2379

1886

}

2380

1887

}

2381

1888

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;

1889

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

1890

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

1891

if_index = (AvahiIfIndex) if_nametoindex(interface);

1892

if(if_index == 0){

1893

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

1894

exitcode = EX_UNAVAILABLE;

1895

goto end;

1896

}

1897

1898

if(quit_now){

1899

goto end;

1900

}

1901

1902

/* Re-raise priviliges */

1903

errno = 0;

1904

ret = seteuid(0);

1905

if(ret == -1){

1906

perror_plus("seteuid");

1907

}

1908

1909

#ifdef __linux__

1910

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1911

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

1912

ret = klogctl(8, NULL, 5);

1913

bool restore_loglevel = true;

1914

if(ret == -1){

1915

restore_loglevel = false;

1916

perror_plus("klogctl");

1917

}

1918

#endif /* __linux__ */

1919

1920

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1921

if(sd < 0){

1922

perror_plus("socket");

1923

exitcode = EX_OSERR;

1924

#ifdef __linux__

1925

if(restore_loglevel){

1926

ret = klogctl(7, NULL, 0);

1927

if(ret == -1){

1928

perror_plus("klogctl");

1929

}

1930

}

1931

#endif /* __linux__ */

1932

/* Lower privileges */

1933

errno = 0;

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

1938

goto end;

1939

}

1940

strcpy(network.ifr_name, interface);

1941

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

1942

if(ret == -1){

1943

perror_plus("ioctl SIOCGIFFLAGS");

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

1949

}

1950

}

1951

#endif /* __linux__ */

1952

exitcode = EX_OSERR;

1953

/* Lower privileges */

1954

errno = 0;

1955

ret = seteuid(uid);

1956

if(ret == -1){

1957

perror_plus("seteuid");

1958

}

1959

goto end;

1960

}

1961

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

1962

network.ifr_flags |= IFF_UP;

1963

take_down_interface = true;

1964

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

1965

if(ret == -1){

1966

take_down_interface = false;

1967

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1968

exitcode = EX_OSERR;

1969

#ifdef __linux__

1970

if(restore_loglevel){

1971

ret = klogctl(7, NULL, 0);

1972

if(ret == -1){

1973

perror_plus("klogctl");

2433

1974

}

2434

1975

}

1976

#endif /* __linux__ */

1977

/* Lower privileges */

1978

errno = 0;

1979

ret = seteuid(uid);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

goto end;

1984

}

1985

}

1986

/* Sleep checking until interface is running.

1987

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

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCGIFFLAGS");

1992

} else if(network.ifr_flags & IFF_RUNNING){

2435

1993

break;

2436

1994

}

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);

1995

struct timespec sleeptime = { .tv_nsec = 250000000 };

1996

ret = nanosleep(&sleeptime, NULL);

1997

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

1998

perror_plus("nanosleep");

1999

}

2000

}

2001

if(not take_down_interface){

2002

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

2003

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

2004

if(ret == -1){

2005

perror_plus("close");

2006

}

2007

}

2008

#ifdef __linux__

2009

if(restore_loglevel){

2010

/* Restores kernel loglevel to default */

2011

ret = klogctl(7, NULL, 0);

2012

if(ret == -1){

2013

perror_plus("klogctl");

2014

}

2015

}

2016

#endif /* __linux__ */

2017

/* Lower privileges */

2018

errno = 0;

2019

/* Lower privileges */

2020

ret = seteuid(uid);

2021

if(ret == -1){

2022

perror_plus("seteuid");

2023

}

2464

2024

}

2465

2025

2466

2026

if(quit_now){

2467

2027

goto end;

2468

2028

}

2469

2029

2470

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

2030

ret = init_gnutls_global(pubkey, seckey);

2471

2031

if(ret == -1){

2472

2032

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

2473

2033

exitcode = EX_UNAVAILABLE;

2480

2040

goto end;

2481

2041

}

2482

2042

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){

2043

if(mkdtemp(tempdir) == NULL){

2493

2044

perror_plus("mkdtemp");

2494

2045

goto end;

2495

2046

}

2047

tempdir_created = true;

2496

2048

2497

2049

if(quit_now){

2498

2050

goto end;

2499

2051

}

2500

2052

2501

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

2053

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

2502

2054

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

2503

2055

exitcode = EX_UNAVAILABLE;

2504

2056

goto end;

2514

2066

/* Connect directly, do not use Zeroconf */

2515

2067

/* (Mainly meant for debugging) */

2516

2068

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

2517

2518

2069

if(address == NULL){

2519

2070

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

2520

2071

exitcode = EX_USAGE;

2525

2076

goto end;

2526

2077

}

2527

2078

2528

in_port_t port;

2079

uint16_t port;

2529

2080

errno = 0;

2530

2081

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

2531

2082

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

2532

or tmpmax != (in_port_t)tmpmax){

2083

or tmpmax != (uint16_t)tmpmax){

2533

2084

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

2534

2085

exitcode = EX_USAGE;

2535

2086

goto end;

2536

2087

}

2537

2088

2538

2089

if(quit_now){

2539

2090

goto end;

2540

2091

}

2541

2092

2542

port = (in_port_t)tmpmax;

2093

port = (uint16_t)tmpmax;

2543

2094

*address = '\0';

2544

2095

/* Colon in address indicates IPv6 */

2545

2096

int af;

2561

2112

}

2562

2113

2563

2114

while(not quit_now){

2564

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

2565

&mc);

2115

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

2566

2116

if(quit_now or ret == 0){

2567

2117

break;

2568

2118

}

2570

2120

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

2571

2121

(int)retry_interval);

2572

2122

}

2573

sleep((unsigned int)retry_interval);

2123

sleep((int)retry_interval);

2574

2124

}

2575

2125

2576

if(not quit_now){

2126

if (not quit_now){

2577

2127

exitcode = EXIT_SUCCESS;

2578

2128

}

2579

2129

2594

2144

config.publish_domain = 0;

2595

2145

2596

2146

/* Allocate a new server */

2597

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2598

&config, NULL, NULL, &ret_errno);

2147

mc.server = avahi_server_new(avahi_simple_poll_get

2148

(mc.simple_poll), &config, NULL,

2149

NULL, &error);

2599

2150

2600

2151

/* Free the Avahi configuration data */

2601

2152

avahi_server_config_free(&config);

2604

2155

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

2605

2156

if(mc.server == NULL){

2606

2157

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

2607

avahi_strerror(ret_errno));

2158

avahi_strerror(error));

2608

2159

exitcode = EX_UNAVAILABLE;

2609

2160

goto end;

2610

2161

}

2616

2167

/* Create the Avahi service browser */

2617

2168

sb = avahi_s_service_browser_new(mc.server, if_index,

2618

2169

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2619

NULL, 0, browse_callback,

2620

(void *)&mc);

2170

NULL, 0, browse_callback, NULL);

2621

2171

if(sb == NULL){

2622

2172

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

2623

2173

avahi_strerror(avahi_server_errno(mc.server)));

2634

2184

if(debug){

2635

2185

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

2636

2186

}

2637

2638

ret = avahi_loop_with_timeout(simple_poll,

2639

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

2187

2188

ret = avahi_loop_with_timeout(mc.simple_poll,

2189

(int)(retry_interval * 1000));

2640

2190

if(debug){

2641

2191

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

2642

2192

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

2649

2199

}

2650

2200

2651

2201

/* Cleanup things */

2652

free(mc.interfaces);

2653

2654

2202

if(sb != NULL)

2655

2203

avahi_s_service_browser_free(sb);

2656

2204

2657

2205

if(mc.server != NULL)

2658

2206

avahi_server_free(mc.server);

2659

2207

2660

if(simple_poll != NULL)

2661

avahi_simple_poll_free(simple_poll);

2208

if(mc.simple_poll != NULL)

2209

avahi_simple_poll_free(mc.simple_poll);

2662

2210

2663

2211

if(gnutls_initialized){

2664

2212

gnutls_certificate_free_credentials(mc.cred);

2676

2224

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

2677

2225

while(mc.current_server != NULL){

2678

2226

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

2687

2227

free(mc.current_server);

2688

2228

mc.current_server = next;

2689

2229

}

2690

2230

}

2691

2231

2692

/* Re-raise privileges */

2232

/* Run network hooks */

2233

run_network_hooks("stop", interface, delay);

2234

2235

/* Re-raise priviliges */

2693

2236

{

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

}

2237

errno = 0;

2238

ret = seteuid(0);

2239

if(ret == -1){

2240

perror_plus("seteuid");

2721

2241

}

2722

2242

2723

ret_errno = lower_privileges_permanently();

2724

if(ret_errno != 0){

2725

errno = ret_errno;

2726

perror_plus("Failed to lower privileges permanently");

2243

/* Take down the network interface */

2244

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

2245

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

2246

if(ret == -1){

2247

perror_plus("ioctl SIOCGIFFLAGS");

2248

} else if(network.ifr_flags & IFF_UP){

2249

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

2250

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

2251

if(ret == -1){

2252

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2253

}

2254

}

2255

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

2256

if(ret == -1){

2257

perror_plus("close");

2258

}

2727

2259

}

2728

2260

}

2729

2730

free(interfaces_to_take_down);

2731

free(interfaces_hooks);

2261

/* Lower privileges permanently */

2262

errno = 0;

2263

ret = setuid(uid);

2264

if(ret == -1){

2265

perror_plus("setuid");

2266

}

2732

2267

2733

2268

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

2734

if(tempdir != NULL){

2269

if(tempdir_created){

2735

2270

struct dirent **direntries = NULL;

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

}

2271

struct dirent *direntry = NULL;

2272

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

2273

alphasort);

2274

if (numentries > 0){

2275

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

2276

direntry = direntries[i];

2277

char *fullname = NULL;

2278

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

2279

direntry->d_name);

2280

if(ret < 0){

2281

perror_plus("asprintf");

2282

continue;

2283

}

2284

ret = remove(fullname);

2285

if(ret == -1){

2286

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

2287

strerror(errno));

2288

}

2289

free(fullname);

2773

2290

}

2774

TEMP_FAILURE_RETRY(close(tempdir_fd));

2291

}

2292

2293

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

2294

free(direntries);

2295

if (numentries == -1){

2296

perror_plus("scandir");

2297

}

2298

ret = rmdir(tempdir);

2299

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

2300

perror_plus("rmdir");

2775

2301

}

2776

2302

}

2777

2303