/mandos/release : revision 237.7.422

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

* modify it under the terms of the GNU General Public License as

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

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42

#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 */

45

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

46

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

47

strtof(), abort() */

48

#include <stdbool.h> /* bool, false, true */

49

#include <string.h> /* memset(), strcmp(), strlen(),

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strerror(), asprintf(), strcpy() */

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#include <string.h> /* strcmp(), strlen(), strerror(),

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asprintf(), strncpy(), strsignal()

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*/

51

52

#include <sys/ioctl.h> /* ioctl */

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53

#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

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sockaddr_in6, PF_INET6,

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56

opendir(), DIR */

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57

#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(),

60

getnameinfo() */

61

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

60

62

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

61

63

*/

62

64

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

63

65

strtoimax() */

64

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

65

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

66

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

67

EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

69

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

70

ENOTEMPTY,

66

71

program_invocation_short_name */

67

72

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

68

73

#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,

73

78

*/

74

79

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

75

80

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

76

setgid(), pause() */

77

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

81

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

82

unlinkat() */

83

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

78

84

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

79

85

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

80

86

argp_state, struct argp,

87

93

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

94

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

89

95

WEXITSTATUS(), WTERMSIG() */

96

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

97

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

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argz_delete(), argz_append(),

99

argz_stringify(), argz_add(),

100

argz_count() */

101

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

102

EAI_SYSTEM, gai_strerror() */

90

103

91

104

#ifdef __linux__

92

105

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

134

147

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

135

148

char *connect_to = NULL;

136

149

const char *hookdir = HOOKDIR;

150

int hookdir_fd = -1;

151

uid_t uid = 65534;

152

gid_t gid = 65534;

137

153

138

154

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

139

155

typedef struct server{

140

156

const char *ip;

141

uint16_t port;

157

in_port_t port;

142

158

AvahiIfIndex if_index;

143

159

int af;

144

160

struct timespec last_seen;

148

164

149

165

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

150

166

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

167

AvahiServer *server;

153

168

gnutls_certificate_credentials_t cred;

154

169

unsigned int dh_bits;

156

171

const char *priority;

157

172

gpgme_ctx_t ctx;

158

173

server *current_server;

174

char *interfaces;

175

size_t interfaces_size;

159

176

} mandos_context;

160

177

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

178

/* global so signal handler can reach it*/

179

AvahiSimplePoll *simple_poll;

166

180

167

181

sig_atomic_t quit_now = 0;

168

182

int signal_received = 0;

169

183

170

184

/* Function to use when printing errors */

171

185

void perror_plus(const char *print_text){

186

int e = errno;

172

187

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

173

188

program_invocation_short_name);

189

errno = e;

174

190

perror(print_text);

175

191

}

176

192

193

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

177

194

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

178

195

va_list ap;

179

196

va_start (ap, format);

180

197

181

198

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

182

199

program_invocation_short_name));

183

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

200

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

184

201

}

185

202

186

203

/*

188

205

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

189

206

* "buffer_length" is how much is already used.

190

207

*/

208

__attribute__((nonnull, warn_unused_result))

191

209

size_t incbuffer(char **buffer, size_t buffer_length,

192

210

size_t buffer_capacity){

193

211

if(buffer_length + BUFFER_SIZE > buffer_capacity){

194

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

195

if(buffer == NULL){

212

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

213

if(new_buf == NULL){

214

int old_errno = errno;

215

free(*buffer);

216

errno = old_errno;

217

*buffer = NULL;

196

218

return 0;

197

219

}

220

*buffer = new_buf;

198

221

buffer_capacity += BUFFER_SIZE;

199

222

}

200

223

return buffer_capacity;

201

224

}

202

225

203

226

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

204

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

205

int af){

227

__attribute__((nonnull, warn_unused_result))

228

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

229

int af, server **current_server){

206

230

int ret;

207

231

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

208

232

if(new_server == NULL){

209

233

perror_plus("malloc");

210

return -1;

234

return false;

211

235

}

212

236

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

213

237

.port = port,

215

239

.af = af };

216

240

if(new_server->ip == NULL){

217

241

perror_plus("strdup");

218

return -1;

242

free(new_server);

243

return false;

244

}

245

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

246

if(ret == -1){

247

perror_plus("clock_gettime");

248

#ifdef __GNUC__

249

#pragma GCC diagnostic push

250

#pragma GCC diagnostic ignored "-Wcast-qual"

251

#endif

252

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

253

#ifdef __GNUC__

254

#pragma GCC diagnostic pop

255

#endif

256

free(new_server);

257

return false;

219

258

}

220

259

/* Special case of first server */

221

if (mc.current_server == NULL){

260

if(*current_server == NULL){

222

261

new_server->next = new_server;

223

262

new_server->prev = new_server;

224

mc.current_server = new_server;

225

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

263

*current_server = new_server;

226

264

} else {

227

new_server->next = mc.current_server;

228

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

265

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

266

new_server->next = *current_server;

267

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

229

268

new_server->prev->next = new_server;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

269

(*current_server)->prev = new_server;

270

}

271

return true;

238

272

}

239

273

240

274

/*

241

275

* Initialize GPGME.

242

276

*/

243

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

244

const char *tempdir){

277

__attribute__((nonnull, warn_unused_result))

278

static bool init_gpgme(const char * const seckey,

279

const char * const pubkey,

280

const char * const tempdir,

281

mandos_context *mc){

245

282

gpgme_error_t rc;

246

283

gpgme_engine_info_t engine_info;

247

284

248

249

285

/*

250

286

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

251

287

*/

252

bool import_key(const char *filename){

288

bool import_key(const char * const filename){

253

289

int ret;

254

290

int fd;

255

291

gpgme_data_t pgp_data;

267

303

return false;

268

304

}

269

305

270

rc = gpgme_op_import(mc.ctx, pgp_data);

306

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

271

307

if(rc != GPG_ERR_NO_ERROR){

272

308

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

273

309

gpgme_strsource(rc), gpgme_strerror(rc));

274

310

return false;

275

311

}

276

312

277

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

313

ret = close(fd);

278

314

if(ret == -1){

279

315

perror_plus("close");

280

316

}

317

353

}

318

354

319

355

/* Create new GPGME "context" */

320

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

356

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

321

357

if(rc != GPG_ERR_NO_ERROR){

322

358

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

323

359

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

336

372

* Decrypt OpenPGP data.

337

373

* Returns -1 on error

338

374

*/

375

__attribute__((nonnull, warn_unused_result))

339

376

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

377

size_t crypto_size,

341

char **plaintext){

378

char **plaintext,

379

mandos_context *mc){

342

380

gpgme_data_t dh_crypto, dh_plain;

343

381

gpgme_error_t rc;

344

382

ssize_t ret;

370

408

371

409

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

372

410

data buffer */

373

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

411

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

374

412

if(rc != GPG_ERR_NO_ERROR){

375

413

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

376

414

gpgme_strsource(rc), gpgme_strerror(rc));

377

415

plaintext_length = -1;

378

416

if(debug){

379

417

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

418

result = gpgme_op_decrypt_result(mc->ctx);

381

419

if(result == NULL){

382

420

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

383

421

} else {

460

498

return plaintext_length;

461

499

}

462

500

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

466

if(ret == NULL)

467

ret = "(unknown)";

468

return ret;

501

__attribute__((warn_unused_result, const))

502

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

503

if(str == NULL)

504

return "(unknown)";

505

return str;

506

}

507

508

__attribute__((warn_unused_result))

509

static const char *safer_gnutls_strerror(int value){

510

const char *ret = gnutls_strerror(value);

511

return safe_string(ret);

469

512

}

470

513

471

514

/* GnuTLS log function callback */

515

__attribute__((nonnull))

472

516

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

473

517

const char* string){

474

518

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

475

519

}

476

520

521

__attribute__((nonnull(1, 2, 4), warn_unused_result))

477

522

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

523

const char *seckeyfilename,

524

const char *dhparamsfilename,

525

mandos_context *mc){

479

526

int ret;

527

unsigned int uret;

480

528

481

529

if(debug){

482

530

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

483

531

}

484

532

485

ret = gnutls_global_init();

486

if(ret != GNUTLS_E_SUCCESS){

487

fprintf_plus(stderr, "GnuTLS global_init: %s\n",

488

safer_gnutls_strerror(ret));

489

return -1;

490

}

491

492

533

if(debug){

493

534

/* "Use a log level over 10 to enable all debugging options."

494

535

* - GnuTLS manual

498

539

}

499

540

500

541

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

542

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

543

if(ret != GNUTLS_E_SUCCESS){

503

544

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

504

545

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

506

546

return -1;

507

547

}

508

548

514

554

}

515

555

516

556

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

557

(mc->cred, pubkeyfilename, seckeyfilename,

518

558

GNUTLS_OPENPGP_FMT_BASE64);

519

559

if(ret != GNUTLS_E_SUCCESS){

520

560

fprintf_plus(stderr,

526

566

}

527

567

528

568

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

569

ret = gnutls_dh_params_init(&mc->dh_params);

530

570

if(ret != GNUTLS_E_SUCCESS){

531

571

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

572

" initialization: %s\n",

533

573

safer_gnutls_strerror(ret));

534

574

goto globalfail;

535

575

}

536

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

537

if(ret != GNUTLS_E_SUCCESS){

538

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

539

safer_gnutls_strerror(ret));

540

goto globalfail;

541

}

542

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

576

/* If a Diffie-Hellman parameters file was given, try to use it */

577

if(dhparamsfilename != NULL){

578

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

579

do {

580

int dhpfile = open(dhparamsfilename, O_RDONLY);

581

if(dhpfile == -1){

582

perror_plus("open");

583

dhparamsfilename = NULL;

584

break;

585

}

586

size_t params_capacity = 0;

587

while(true){

588

params_capacity = incbuffer((char **)&params.data,

589

(size_t)params.size,

590

(size_t)params_capacity);

591

if(params_capacity == 0){

592

perror_plus("incbuffer");

593

free(params.data);

594

params.data = NULL;

595

dhparamsfilename = NULL;

596

break;

597

}

598

ssize_t bytes_read = read(dhpfile,

599

params.data + params.size,

600

BUFFER_SIZE);

601

/* EOF */

602

if(bytes_read == 0){

603

break;

604

}

605

/* check bytes_read for failure */

606

if(bytes_read < 0){

607

perror_plus("read");

608

free(params.data);

609

params.data = NULL;

610

dhparamsfilename = NULL;

611

break;

612

}

613

params.size += (unsigned int)bytes_read;

614

}

615

if(params.data == NULL){

616

dhparamsfilename = NULL;

617

}

618

if(dhparamsfilename == NULL){

619

break;

620

}

621

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

622

GNUTLS_X509_FMT_PEM);

623

if(ret != GNUTLS_E_SUCCESS){

624

fprintf_plus(stderr, "Failed to parse DH parameters in file"

625

" \"%s\": %s\n", dhparamsfilename,

626

safer_gnutls_strerror(ret));

627

dhparamsfilename = NULL;

628

}

629

} while(false);

630

}

631

if(dhparamsfilename == NULL){

632

if(mc->dh_bits == 0){

633

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

634

/* Try to read the private key file */

635

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

636

do {

637

int secfile = open(seckeyfilename, O_RDONLY);

638

if(secfile == -1){

639

perror_plus("open");

640

break;

641

}

642

size_t buffer_capacity = 0;

643

while(true){

644

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

645

(size_t)buffer.size,

646

(size_t)buffer_capacity);

647

if(buffer_capacity == 0){

648

perror_plus("incbuffer");

649

free(buffer.data);

650

buffer.data = NULL;

651

break;

652

}

653

ssize_t bytes_read = read(secfile,

654

buffer.data + buffer.size,

655

BUFFER_SIZE);

656

/* EOF */

657

if(bytes_read == 0){

658

break;

659

}

660

/* check bytes_read for failure */

661

if(bytes_read < 0){

662

perror_plus("read");

663

free(buffer.data);

664

buffer.data = NULL;

665

break;

666

}

667

buffer.size += (unsigned int)bytes_read;

668

}

669

close(secfile);

670

} while(false);

671

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

672

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

673

if(buffer.data != NULL){

674

{

675

gnutls_openpgp_privkey_t privkey = NULL;

676

ret = gnutls_openpgp_privkey_init(&privkey);

677

if(ret != GNUTLS_E_SUCCESS){

678

fprintf_plus(stderr, "Error initializing OpenPGP key"

679

" structure: %s",

680

safer_gnutls_strerror(ret));

681

free(buffer.data);

682

buffer.data = NULL;

683

} else {

684

ret = gnutls_openpgp_privkey_import

685

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

686

if(ret != GNUTLS_E_SUCCESS){

687

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

688

safer_gnutls_strerror(ret));

689

privkey = NULL;

690

}

691

free(buffer.data);

692

buffer.data = NULL;

693

if(privkey != NULL){

694

/* Use private key to suggest an appropriate

695

sec_param */

696

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

697

gnutls_openpgp_privkey_deinit(privkey);

698

if(debug){

699

fprintf_plus(stderr, "This OpenPGP key implies using"

700

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

701

safe_string(gnutls_sec_param_get_name

702

(sec_param)));

703

}

704

}

705

}

706

}

707

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

708

/* Err on the side of caution */

709

sec_param = GNUTLS_SEC_PARAM_ULTRA;

710

if(debug){

711

fprintf_plus(stderr, "Falling back to security parameter"

712

" \"%s\"\n",

713

safe_string(gnutls_sec_param_get_name

714

(sec_param)));

715

}

716

}

717

}

718

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

719

if(uret != 0){

720

mc->dh_bits = uret;

721

if(debug){

722

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

723

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

724

safe_string(gnutls_sec_param_get_name

725

(sec_param)),

726

mc->dh_bits);

727

}

728

} else {

729

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

730

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

731

safe_string(gnutls_sec_param_get_name

732

(sec_param)),

733

safer_gnutls_strerror(ret));

734

goto globalfail;

735

}

736

} else if(debug){

737

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

738

mc->dh_bits);

739

}

740

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

741

if(ret != GNUTLS_E_SUCCESS){

742

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

743

" bits): %s\n", mc->dh_bits,

744

safer_gnutls_strerror(ret));

745

goto globalfail;

746

}

747

}

748

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

544

749

545

750

return 0;

546

751

547

752

globalfail:

548

753

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

754

gnutls_certificate_free_credentials(mc->cred);

755

gnutls_dh_params_deinit(mc->dh_params);

552

756

return -1;

553

757

}

554

758

555

static int init_gnutls_session(gnutls_session_t *session){

759

__attribute__((nonnull, warn_unused_result))

760

static int init_gnutls_session(gnutls_session_t *session,

761

mandos_context *mc){

556

762

int ret;

557

763

/* GnuTLS session creation */

558

764

do {

570

776

{

571

777

const char *err;

572

778

do {

573

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

779

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

574

780

if(quit_now){

575

781

gnutls_deinit(*session);

576

782

return -1;

587

793

588

794

do {

589

795

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

796

mc->cred);

591

797

if(quit_now){

592

798

gnutls_deinit(*session);

593

799

return -1;

603

809

/* ignore client certificate if any. */

604

810

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

811

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

812

return 0;

609

813

}

610

814

612

816

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

613

817

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

614

818

819

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

820

__attribute__((warn_unused_result))

821

int raise_privileges(void){

822

int old_errno = errno;

823

int ret = 0;

824

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

825

ret = errno;

826

}

827

errno = old_errno;

828

return ret;

829

}

830

831

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

832

__attribute__((warn_unused_result))

833

int raise_privileges_permanently(void){

834

int old_errno = errno;

835

int ret = raise_privileges();

836

if(ret != 0){

837

errno = old_errno;

838

return ret;

839

}

840

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

841

ret = errno;

842

}

843

errno = old_errno;

844

return ret;

845

}

846

847

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

848

__attribute__((warn_unused_result))

849

int lower_privileges(void){

850

int old_errno = errno;

851

int ret = 0;

852

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

853

ret = errno;

854

}

855

errno = old_errno;

856

return ret;

857

}

858

859

/* Lower privileges permanently */

860

__attribute__((warn_unused_result))

861

int lower_privileges_permanently(void){

862

int old_errno = errno;

863

int ret = 0;

864

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

865

ret = errno;

866

}

867

errno = old_errno;

868

return ret;

869

}

870

871

/* Helper function to add_local_route() and delete_local_route() */

872

__attribute__((nonnull, warn_unused_result))

873

static bool add_delete_local_route(const bool add,

874

const char *address,

875

AvahiIfIndex if_index){

876

int ret;

877

char helper[] = "mandos-client-iprouteadddel";

878

char add_arg[] = "add";

879

char delete_arg[] = "delete";

880

char debug_flag[] = "--debug";

881

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

882

if(pluginhelperdir == NULL){

883

if(debug){

884

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

885

" variable not set; cannot run helper\n");

886

}

887

return false;

888

}

889

890

char interface[IF_NAMESIZE];

891

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

892

perror_plus("if_indextoname");

893

return false;

894

}

895

896

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

897

if(devnull == -1){

898

perror_plus("open(\"/dev/null\", O_RDONLY)");

899

return false;

900

}

901

pid_t pid = fork();

902

if(pid == 0){

903

/* Child */

904

/* Raise privileges */

905

errno = raise_privileges_permanently();

906

if(errno != 0){

907

perror_plus("Failed to raise privileges");

908

/* _exit(EX_NOPERM); */

909

} else {

910

/* Set group */

911

errno = 0;

912

ret = setgid(0);

913

if(ret == -1){

914

perror_plus("setgid");

915

_exit(EX_NOPERM);

916

}

917

/* Reset supplementary groups */

918

errno = 0;

919

ret = setgroups(0, NULL);

920

if(ret == -1){

921

perror_plus("setgroups");

922

_exit(EX_NOPERM);

923

}

924

}

925

ret = dup2(devnull, STDIN_FILENO);

926

if(ret == -1){

927

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

928

_exit(EX_OSERR);

929

}

930

ret = close(devnull);

931

if(ret == -1){

932

perror_plus("close");

933

_exit(EX_OSERR);

934

}

935

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

936

if(ret == -1){

937

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

938

_exit(EX_OSERR);

939

}

940

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

941

O_RDONLY

942

| O_DIRECTORY

943

| O_PATH

944

| O_CLOEXEC));

945

if(helperdir_fd == -1){

946

perror_plus("open");

947

_exit(EX_UNAVAILABLE);

948

}

949

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

950

helper, O_RDONLY));

951

if(helper_fd == -1){

952

perror_plus("openat");

953

close(helperdir_fd);

954

_exit(EX_UNAVAILABLE);

955

}

956

close(helperdir_fd);

957

#ifdef __GNUC__

958

#pragma GCC diagnostic push

959

#pragma GCC diagnostic ignored "-Wcast-qual"

960

#endif

961

if(fexecve(helper_fd, (char *const [])

962

{ helper, add ? add_arg : delete_arg, (char *)address,

963

interface, debug ? debug_flag : NULL, NULL },

964

environ) == -1){

965

#ifdef __GNUC__

966

#pragma GCC diagnostic pop

967

#endif

968

perror_plus("fexecve");

969

_exit(EXIT_FAILURE);

970

}

971

}

972

if(pid == -1){

973

perror_plus("fork");

974

return false;

975

}

976

int status;

977

pid_t pret = -1;

978

errno = 0;

979

do {

980

pret = waitpid(pid, &status, 0);

981

if(pret == -1 and errno == EINTR and quit_now){

982

int errno_raising = 0;

983

if((errno = raise_privileges()) != 0){

984

errno_raising = errno;

985

perror_plus("Failed to raise privileges in order to"

986

" kill helper program");

987

}

988

if(kill(pid, SIGTERM) == -1){

989

perror_plus("kill");

990

}

991

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

992

perror_plus("Failed to lower privileges after killing"

993

" helper program");

994

}

995

return false;

996

}

997

} while(pret == -1 and errno == EINTR);

998

if(pret == -1){

999

perror_plus("waitpid");

1000

return false;

1001

}

1002

if(WIFEXITED(status)){

1003

if(WEXITSTATUS(status) != 0){

1004

fprintf_plus(stderr, "Error: iprouteadddel exited"

1005

" with status %d\n", WEXITSTATUS(status));

1006

return false;

1007

}

1008

return true;

1009

}

1010

if(WIFSIGNALED(status)){

1011

fprintf_plus(stderr, "Error: iprouteadddel died by"

1012

" signal %d\n", WTERMSIG(status));

1013

return false;

1014

}

1015

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

1016

return false;

1017

}

1018

1019

__attribute__((nonnull, warn_unused_result))

1020

static bool add_local_route(const char *address,

1021

AvahiIfIndex if_index){

1022

if(debug){

1023

fprintf_plus(stderr, "Adding route to %s\n", address);

1024

}

1025

return add_delete_local_route(true, address, if_index);

1026

}

1027

1028

__attribute__((nonnull, warn_unused_result))

1029

static bool delete_local_route(const char *address,

1030

AvahiIfIndex if_index){

1031

if(debug){

1032

fprintf_plus(stderr, "Removing route to %s\n", address);

1033

}

1034

return add_delete_local_route(false, address, if_index);

1035

}

1036

615

1037

/* Called when a Mandos server is found */

616

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

1038

__attribute__((nonnull, warn_unused_result))

1039

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

617

1040

AvahiIfIndex if_index,

618

int af){

1041

int af, mandos_context *mc){

619

1042

int ret, tcp_sd = -1;

620

1043

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1044

struct sockaddr_storage to;

625

1045

char *buffer = NULL;

626

1046

char *decrypted_buffer = NULL;

627

1047

size_t buffer_length = 0;

630

1050

int retval = -1;

631

1051

gnutls_session_t session;

632

1052

int pf; /* Protocol family */

1053

bool route_added = false;

633

1054

634

1055

errno = 0;

635

1056

651

1072

return -1;

652

1073

}

653

1074

654

ret = init_gnutls_session(&session);

1075

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

1076

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

1077

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

1078

bool match = false;

1079

{

1080

char *interface = NULL;

1081

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

1082

interface))){

1083

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

1084

match = true;

1085

break;

1086

}

1087

}

1088

}

1089

if(not match){

1090

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

1091

connect to the server */

1092

if(debug){

1093

char interface[IF_NAMESIZE];

1094

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

1095

perror_plus("if_indextoname");

1096

} else {

1097

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

1098

" \"%s\"\n",

1099

if_indextoname((unsigned int)if_index,

1100

interface));

1101

}

1102

}

1103

return -1;

1104

}

1105

}

1106

1107

ret = init_gnutls_session(&session, mc);

655

1108

if(ret != 0){

656

1109

return -1;

657

1110

}

658

1111

659

1112

if(debug){

660

1113

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

661

PRIu16 "\n", ip, port);

1114

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

662

1115

}

663

1116

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1117

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

665

1118

if(tcp_sd < 0){

666

1119

int e = errno;

667

1120

perror_plus("socket");

674

1127

goto mandos_end;

675

1128

}

676

1129

677

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

678

1130

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1131

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1132

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1133

ret = inet_pton(af, ip, &to6->sin6_addr);

681

1134

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

1135

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1136

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1137

ret = inet_pton(af, ip, &to4->sin_addr);

684

1138

}

685

1139

if(ret < 0 ){

686

1140

int e = errno;

695

1149

goto mandos_end;

696

1150

}

697

1151

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

1152

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

1153

if(IN6_IS_ADDR_LINKLOCAL

1154

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

705

1155

if(if_index == AVAHI_IF_UNSPEC){

706

1156

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

707

1157

" incomplete without a network interface\n");

709

1159

goto mandos_end;

710

1160

}

711

1161

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1162

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

713

1163

}

714

1164

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1165

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

718

1166

}

719

1167

720

1168

if(quit_now){

728

1176

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

729

1177

perror_plus("if_indextoname");

730

1178

} else {

731

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

732

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

1179

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

1180

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

733

1181

}

734

1182

} else {

735

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

736

ip, port);

1183

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

1184

ip, (uintmax_t)port);

737

1185

}

738

1186

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1187

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

741

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

744

} else {

745

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

746

sizeof(addrstr));

747

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

754

}

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

760

}

761

762

if(af == AF_INET6){

763

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

764

} else {

765

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

766

}

767

if(ret < 0){

768

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

769

int e = errno;

770

perror_plus("connect");

771

errno = e;

772

}

773

goto mandos_end;

774

}

775

776

if(quit_now){

777

errno = EINTR;

778

goto mandos_end;

1188

if(af == AF_INET6){

1189

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

1190

sizeof(struct sockaddr_in6),

1191

addrstr, sizeof(addrstr), NULL, 0,

1192

NI_NUMERICHOST);

1193

} else {

1194

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

1195

sizeof(struct sockaddr_in),

1196

addrstr, sizeof(addrstr), NULL, 0,

1197

NI_NUMERICHOST);

1198

}

1199

if(ret == EAI_SYSTEM){

1200

perror_plus("getnameinfo");

1201

} else if(ret != 0) {

1202

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

1203

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

1204

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

1205

}

1206

}

1207

1208

if(quit_now){

1209

errno = EINTR;

1210

goto mandos_end;

1211

}

1212

1213

while(true){

1214

if(af == AF_INET6){

1215

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

1216

sizeof(struct sockaddr_in6));

1217

} else {

1218

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

1219

sizeof(struct sockaddr_in));

1220

}

1221

if(ret < 0){

1222

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1223

and if_index != AVAHI_IF_UNSPEC

1224

and connect_to == NULL

1225

and not route_added and

1226

((af == AF_INET6 and not

1227

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1228

&to)->sin6_addr)))

1229

or (af == AF_INET and

1230

/* Not a a IPv4LL address */

1231

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1232

& 0xFFFF0000L) != 0xA9FE0000L))){

1233

/* Work around Avahi bug - Avahi does not announce link-local

1234

addresses if it has a global address, so local hosts with

1235

*only* a link-local address (e.g. Mandos clients) cannot

1236

connect to a Mandos server announced by Avahi on a server

1237

host with a global address. Work around this by retrying

1238

with an explicit route added with the server's address.

1239

1240

Avahi bug reference:

1241

https://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1242

https://bugs.debian.org/587961

1243

*/

1244

if(debug){

1245

fprintf_plus(stderr, "Mandos server unreachable, trying"

1246

" direct route\n");

1247

}

1248

int e = errno;

1249

route_added = add_local_route(ip, if_index);

1250

if(route_added){

1251

continue;

1252

}

1253

errno = e;

1254

}

1255

if(errno != ECONNREFUSED or debug){

1256

int e = errno;

1257

perror_plus("connect");

1258

errno = e;

1259

}

1260

goto mandos_end;

1261

}

1262

1263

if(quit_now){

1264

errno = EINTR;

1265

goto mandos_end;

1266

}

1267

break;

779

1268

}

780

1269

781

1270

const char *out = mandos_protocol_version;

817

1306

goto mandos_end;

818

1307

}

819

1308

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1309

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

1310

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

1311

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

1312

gnutls_transport_set_ptr(session,

1313

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

1314

823

1315

if(quit_now){

824

1316

errno = EINTR;

929

1421

if(buffer_length > 0){

930

1422

ssize_t decrypted_buffer_size;

931

1423

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1424

&decrypted_buffer, mc);

933

1425

if(decrypted_buffer_size >= 0){

934

1426

1427

clearerr(stdout);

935

1428

written = 0;

936

1429

while(written < (size_t) decrypted_buffer_size){

937

1430

if(quit_now){

953

1446

}

954

1447

written += (size_t)ret;

955

1448

}

1449

ret = fflush(stdout);

1450

if(ret != 0){

1451

int e = errno;

1452

if(debug){

1453

fprintf_plus(stderr, "Error writing encrypted data: %s\n",

1454

strerror(errno));

1455

}

1456

errno = e;

1457

goto mandos_end;

1458

}

956

1459

retval = 0;

957

1460

}

958

1461

}

961

1464

962

1465

mandos_end:

963

1466

{

1467

if(route_added){

1468

if(not delete_local_route(ip, if_index)){

1469

fprintf_plus(stderr, "Failed to delete local route to %s on"

1470

" interface %d", ip, if_index);

1471

}

1472

}

964

1473

int e = errno;

965

1474

free(decrypted_buffer);

966

1475

free(buffer);

967

1476

if(tcp_sd >= 0){

968

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

1477

ret = close(tcp_sd);

969

1478

}

970

1479

if(ret == -1){

971

1480

if(e == 0){

983

1492

return retval;

984

1493

}

985

1494

1495

__attribute__((nonnull))

986

1496

static void resolve_callback(AvahiSServiceResolver *r,

987

1497

AvahiIfIndex interface,

988

1498

AvahiProtocol proto,

996

1506

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1507

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1508

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1509

void *mc){

1510

if(r == NULL){

1511

return;

1512

}

1001

1513

1002

1514

/* Called whenever a service has been resolved successfully or

1003

1515

timed out */

1004

1516

1005

1517

if(quit_now){

1518

avahi_s_service_resolver_free(r);

1006

1519

return;

1007

1520

}

1008

1521

1012

1525

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

1013

1526

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

1014

1527

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1528

avahi_strerror(avahi_server_errno

1529

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

1016

1530

break;

1017

1531

1018

1532

case AVAHI_RESOLVER_FOUND:

1024

1538

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

1025

1539

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

1026

1540

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1541

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

1542

interface,

1543

avahi_proto_to_af(proto),

1544

mc);

1029

1545

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1546

avahi_simple_poll_quit(simple_poll);

1031

1547

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1548

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

1549

avahi_proto_to_af(proto),

1550

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

1551

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

1552

" list\n", name);

1553

}

1034

1554

}

1035

1555

}

1036

1556

}

1046

1566

const char *domain,

1047

1567

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1568

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1569

void *mc){

1570

if(b == NULL){

1571

return;

1572

}

1051

1573

1052

1574

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

1053

1575

is removed from the LAN */

1061

1583

case AVAHI_BROWSER_FAILURE:

1062

1584

1063

1585

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1586

avahi_strerror(avahi_server_errno

1587

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

1588

avahi_simple_poll_quit(simple_poll);

1066

1589

return;

1067

1590

1068

1591

case AVAHI_BROWSER_NEW:

1071

1594

the callback function is called the Avahi server will free the

1072

1595

resolver for us. */

1073

1596

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1597

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

1598

interface, protocol, name, type,

1599

domain, protocol, 0,

1600

resolve_callback, mc) == NULL)

1077

1601

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

1078

1602

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1603

avahi_strerror(avahi_server_errno

1604

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

1080

1605

break;

1081

1606

1082

1607

case AVAHI_BROWSER_REMOVE:

1101

1626

signal_received = sig;

1102

1627

int old_errno = errno;

1103

1628

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1629

if(simple_poll != NULL){

1630

avahi_simple_poll_quit(simple_poll);

1106

1631

}

1107

1632

errno = old_errno;

1108

1633

}

1109

1634

1635

__attribute__((nonnull, warn_unused_result))

1110

1636

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

1111

1637

int ret;

1638

int old_errno;

1112

1639

1113

1640

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

1114

1641

if(s < 0){

1642

old_errno = errno;

1115

1643

perror_plus("socket");

1644

errno = old_errno;

1116

1645

return false;

1117

1646

}

1118

strcpy(ifr->ifr_name, ifname);

1647

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1648

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1119

1649

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1650

if(ret == -1){

1121

1651

if(debug){

1652

old_errno = errno;

1122

1653

perror_plus("ioctl SIOCGIFFLAGS");

1654

errno = old_errno;

1123

1655

}

1124

1656

return false;

1125

1657

}

1126

1658

return true;

1127

1659

}

1128

1660

1661

__attribute__((nonnull, warn_unused_result))

1129

1662

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

1130

1663

1131

1664

/* Reject the loopback device */

1173

1706

* corresponds to an acceptable network device.

1174

1707

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

1175

1708

*/

1709

__attribute__((nonnull, warn_unused_result))

1176

1710

int good_interface(const struct dirent *if_entry){

1177

1711

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

1178

1712

return 0;

1194

1728

}

1195

1729

1196

1730

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

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

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

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

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1731

* This function determines if a network interface is up.

1732

*/

1733

__attribute__((nonnull, warn_unused_result))

1734

bool interface_is_up(const char *interface){

1735

struct ifreq ifr;

1736

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

1737

if(debug){

1738

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

1739

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

1740

}

1741

return false;

1742

}

1743

1744

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

1745

}

1746

1747

/*

1748

* This function determines if a network interface is running

1749

*/

1750

__attribute__((nonnull, warn_unused_result))

1751

bool interface_is_running(const char *interface){

1752

struct ifreq ifr;

1753

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

1754

if(debug){

1755

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

1756

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

1757

}

1758

return false;

1759

}

1760

1761

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

1762

}

1763

1764

__attribute__((nonnull, pure, warn_unused_result))

1239

1765

int notdotentries(const struct dirent *direntry){

1240

1766

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

1241

1767

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

1248

1774

}

1249

1775

1250

1776

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

1777

__attribute__((nonnull, warn_unused_result))

1251

1778

int runnable_hook(const struct dirent *direntry){

1252

1779

int ret;

1253

1780

size_t sret;

1261

1788

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

1262

1789

"abcdefghijklmnopqrstuvwxyz"

1263

1790

"0123456789"

1264

"_-");

1791

"_.-");

1265

1792

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

1266

1793

/* Contains non-allowed characters */

1267

1794

if(debug){

1271

1798

return 0;

1272

1799

}

1273

1800

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1801

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

1282

1802

if(ret == -1){

1283

1803

if(debug){

1284

1804

perror_plus("Could not stat hook");

1308

1828

return 1;

1309

1829

}

1310

1830

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1831

__attribute__((nonnull, warn_unused_result))

1832

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1833

mandos_context *mc){

1312

1834

int ret;

1313

1835

struct timespec now;

1314

1836

struct timespec waited_time;

1315

1837

intmax_t block_time;

1316

1838

1317

1839

while(true){

1318

if(mc.current_server == NULL){

1319

if (debug){

1840

if(mc->current_server == NULL){

1841

if(debug){

1320

1842

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

1321

1843

" No timeout!\n");

1322

1844

}

1323

1845

ret = avahi_simple_poll_iterate(s, -1);

1324

1846

} else {

1325

if (debug){

1847

if(debug){

1326

1848

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

1327

1849

" it, or wait\n");

1328

1850

}

1335

1857

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

1336

1858

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

1337

1859

waited_time.tv_sec = (now.tv_sec

1338

- mc.current_server->last_seen.tv_sec);

1860

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

1339

1861

waited_time.tv_nsec = (now.tv_nsec

1340

- mc.current_server->last_seen.tv_nsec);

1862

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

1341

1863

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

1342

1864

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

1343

1865

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

1345

1867

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

1346

1868

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

1347

1869

1348

if (debug){

1870

if(debug){

1349

1871

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

1350

1872

block_time);

1351

1873

}

1352

1874

1353

1875

if(block_time <= 0){

1354

ret = start_mandos_communication(mc.current_server->ip,

1355

mc.current_server->port,

1356

mc.current_server->if_index,

1357

mc.current_server->af);

1876

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

1877

mc->current_server->port,

1878

mc->current_server->if_index,

1879

mc->current_server->af, mc);

1358

1880

if(ret == 0){

1359

avahi_simple_poll_quit(mc.simple_poll);

1881

avahi_simple_poll_quit(s);

1360

1882

return 0;

1361

1883

}

1362

1884

ret = clock_gettime(CLOCK_MONOTONIC,

1363

&mc.current_server->last_seen);

1885

&mc->current_server->last_seen);

1364

1886

if(ret == -1){

1365

1887

perror_plus("clock_gettime");

1366

1888

return -1;

1367

1889

}

1368

mc.current_server = mc.current_server->next;

1890

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

1369

1891

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

1370

1892

servers, but don't block */

1371

1893

}

1373

1895

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

1374

1896

}

1375

1897

if(ret != 0){

1376

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

1898

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

1377

1899

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

1378

1900

}

1379

1901

}

1380

1902

}

1381

1903

}

1382

1904

1383

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

1905

__attribute__((nonnull))

1906

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

1384

1907

const float delay){

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1908

struct dirent **direntries = NULL;

1909

if(hookdir_fd == -1){

1910

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1911

| O_CLOEXEC);

1912

if(hookdir_fd == -1){

1913

if(errno == ENOENT){

1914

if(debug){

1915

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

1916

" found\n", hookdir);

1917

}

1918

} else {

1919

perror_plus("open");

1920

}

1921

return;

1922

}

1923

}

1924

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

1925

runnable_hook, alphasort);

1390

1926

if(numhooks == -1){

1391

1927

perror_plus("scandir");

1392

} else {

1393

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

1394

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

1395

direntry = direntries[i];

1396

char *fullname = NULL;

1397

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

1398

if(ret < 0){

1928

return;

1929

}

1930

struct dirent *direntry;

1931

int ret;

1932

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

1933

if(devnull == -1){

1934

perror_plus("open(\"/dev/null\", O_RDONLY)");

1935

return;

1936

}

1937

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

1938

direntry = direntries[i];

1939

if(debug){

1940

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

1941

direntry->d_name);

1942

}

1943

pid_t hook_pid = fork();

1944

if(hook_pid == 0){

1945

/* Child */

1946

/* Raise privileges */

1947

errno = raise_privileges_permanently();

1948

if(errno != 0){

1949

perror_plus("Failed to raise privileges");

1950

_exit(EX_NOPERM);

1951

}

1952

/* Set group */

1953

errno = 0;

1954

ret = setgid(0);

1955

if(ret == -1){

1956

perror_plus("setgid");

1957

_exit(EX_NOPERM);

1958

}

1959

/* Reset supplementary groups */

1960

errno = 0;

1961

ret = setgroups(0, NULL);

1962

if(ret == -1){

1963

perror_plus("setgroups");

1964

_exit(EX_NOPERM);

1965

}

1966

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

1967

if(ret == -1){

1968

perror_plus("setenv");

1969

_exit(EX_OSERR);

1970

}

1971

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

1972

if(ret == -1){

1973

perror_plus("setenv");

1974

_exit(EX_OSERR);

1975

}

1976

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

1977

if(ret == -1){

1978

perror_plus("setenv");

1979

_exit(EX_OSERR);

1980

}

1981

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

1982

if(ret == -1){

1983

perror_plus("setenv");

1984

_exit(EX_OSERR);

1985

}

1986

char *delaystring;

1987

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

1988

if(ret == -1){

1399

1989

perror_plus("asprintf");

1400

continue;

1401

}

1402

if(debug){

1403

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

1404

direntry->d_name);

1405

}

1406

pid_t hook_pid = fork();

1407

if(hook_pid == 0){

1408

/* Child */

1409

dup2(devnull, STDIN_FILENO);

1410

close(devnull);

1411

dup2(STDERR_FILENO, STDOUT_FILENO);

1412

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

1413

if(ret == -1){

1414

perror_plus("setenv");

1415

return false;

1416

}

1417

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

1418

if(ret == -1){

1419

perror_plus("setenv");

1420

return false;

1421

}

1422

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

1423

if(ret == -1){

1424

perror_plus("setenv");

1425

return false;

1426

}

1427

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

1428

if(ret == -1){

1429

perror_plus("setenv");

1430

return false;

1431

}

1432

char *delaystring;

1433

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

1434

if(ret == -1){

1435

perror_plus("asprintf");

1436

return false;

1437

}

1438

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

1439

if(ret == -1){

1440

free(delaystring);

1441

perror_plus("setenv");

1442

return false;

1443

}

1990

_exit(EX_OSERR);

1991

}

1992

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

1993

if(ret == -1){

1444

1994

free(delaystring);

1445

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

1446

perror_plus("execl");

1447

} else {

1448

int status;

1449

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

1450

perror_plus("waitpid");

1451

free(fullname);

1452

continue;

1453

}

1454

if(WIFEXITED(status)){

1455

if(WEXITSTATUS(status) != 0){

1456

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

1457

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

1458

WEXITSTATUS(status));

1459

free(fullname);

1460

continue;

1461

}

1462

} else if(WIFSIGNALED(status)){

1463

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

1464

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

1465

WTERMSIG(status));

1466

free(fullname);

1467

continue;

1468

} else {

1469

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

1470

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

1471

free(fullname);

1472

continue;

1473

}

1474

}

1475

free(fullname);

1476

if(debug){

1477

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

1478

direntry->d_name);

1479

}

1480

}

1481

close(devnull);

1482

}

1483

return true;

1995

perror_plus("setenv");

1996

_exit(EX_OSERR);

1997

}

1998

free(delaystring);

1999

if(connect_to != NULL){

2000

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

2001

if(ret == -1){

2002

perror_plus("setenv");

2003

_exit(EX_OSERR);

2004

}

2005

}

2006

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

2007

direntry->d_name,

2008

O_RDONLY));

2009

if(hook_fd == -1){

2010

perror_plus("openat");

2011

_exit(EXIT_FAILURE);

2012

}

2013

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

2014

perror_plus("close");

2015

_exit(EXIT_FAILURE);

2016

}

2017

ret = dup2(devnull, STDIN_FILENO);

2018

if(ret == -1){

2019

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

2020

_exit(EX_OSERR);

2021

}

2022

ret = close(devnull);

2023

if(ret == -1){

2024

perror_plus("close");

2025

_exit(EX_OSERR);

2026

}

2027

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2028

if(ret == -1){

2029

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

2030

_exit(EX_OSERR);

2031

}

2032

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

2033

environ) == -1){

2034

perror_plus("fexecve");

2035

_exit(EXIT_FAILURE);

2036

}

2037

} else {

2038

if(hook_pid == -1){

2039

perror_plus("fork");

2040

free(direntry);

2041

continue;

2042

}

2043

int status;

2044

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

2045

perror_plus("waitpid");

2046

free(direntry);

2047

continue;

2048

}

2049

if(WIFEXITED(status)){

2050

if(WEXITSTATUS(status) != 0){

2051

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

2052

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

2053

WEXITSTATUS(status));

2054

free(direntry);

2055

continue;

2056

}

2057

} else if(WIFSIGNALED(status)){

2058

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

2059

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

2060

WTERMSIG(status));

2061

free(direntry);

2062

continue;

2063

} else {

2064

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

2065

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

2066

free(direntry);

2067

continue;

2068

}

2069

}

2070

if(debug){

2071

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

2072

direntry->d_name);

2073

}

2074

free(direntry);

2075

}

2076

free(direntries);

2077

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

2078

perror_plus("close");

2079

} else {

2080

hookdir_fd = -1;

2081

}

2082

close(devnull);

2083

}

2084

2085

__attribute__((nonnull, warn_unused_result))

2086

int bring_up_interface(const char *const interface,

2087

const float delay){

2088

int old_errno = errno;

2089

int ret;

2090

struct ifreq network;

2091

unsigned int if_index = if_nametoindex(interface);

2092

if(if_index == 0){

2093

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

2094

errno = old_errno;

2095

return ENXIO;

2096

}

2097

2098

if(quit_now){

2099

errno = old_errno;

2100

return EINTR;

2101

}

2102

2103

if(not interface_is_up(interface)){

2104

int ret_errno = 0;

2105

int ioctl_errno = 0;

2106

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

2107

ret_errno = errno;

2108

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

2109

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

2110

errno = old_errno;

2111

return ret_errno;

2112

}

2113

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

2114

2115

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

2116

if(sd == -1){

2117

ret_errno = errno;

2118

perror_plus("socket");

2119

errno = old_errno;

2120

return ret_errno;

2121

}

2122

2123

if(quit_now){

2124

ret = close(sd);

2125

if(ret == -1){

2126

perror_plus("close");

2127

}

2128

errno = old_errno;

2129

return EINTR;

2130

}

2131

2132

if(debug){

2133

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

2134

interface);

2135

}

2136

2137

/* Raise privileges */

2138

ret_errno = raise_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to raise privileges");

2142

}

2143

2144

#ifdef __linux__

2145

int ret_linux;

2146

bool restore_loglevel = false;

2147

if(ret_errno == 0){

2148

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2149

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

2150

ret_linux = klogctl(8, NULL, 5);

2151

if(ret_linux == -1){

2152

perror_plus("klogctl");

2153

} else {

2154

restore_loglevel = true;

2155

}

2156

}

2157

#endif /* __linux__ */

2158

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

2159

ioctl_errno = errno;

2160

#ifdef __linux__

2161

if(restore_loglevel){

2162

ret_linux = klogctl(7, NULL, 0);

2163

if(ret_linux == -1){

2164

perror_plus("klogctl");

2165

}

2166

}

2167

#endif /* __linux__ */

2168

2169

/* If raise_privileges() succeeded above */

2170

if(ret_errno == 0){

2171

/* Lower privileges */

2172

ret_errno = lower_privileges();

2173

if(ret_errno != 0){

2174

errno = ret_errno;

2175

perror_plus("Failed to lower privileges");

2176

}

2177

}

2178

2179

/* Close the socket */

2180

ret = close(sd);

2181

if(ret == -1){

2182

perror_plus("close");

2183

}

2184

2185

if(ret_setflags == -1){

2186

errno = ioctl_errno;

2187

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2188

errno = old_errno;

2189

return ioctl_errno;

2190

}

2191

} else if(debug){

2192

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

2193

interface);

2194

}

2195

2196

/* Sleep checking until interface is running.

2197

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

2198

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

2199

if(interface_is_running(interface)){

2200

break;

2201

}

2202

struct timespec sleeptime = { .tv_nsec = 250000000 };

2203

ret = nanosleep(&sleeptime, NULL);

2204

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

2205

perror_plus("nanosleep");

2206

}

2207

}

2208

2209

errno = old_errno;

2210

return 0;

2211

}

2212

2213

__attribute__((nonnull, warn_unused_result))

2214

int take_down_interface(const char *const interface){

2215

int old_errno = errno;

2216

struct ifreq network;

2217

unsigned int if_index = if_nametoindex(interface);

2218

if(if_index == 0){

2219

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

2220

errno = old_errno;

2221

return ENXIO;

2222

}

2223

if(interface_is_up(interface)){

2224

int ret_errno = 0;

2225

int ioctl_errno = 0;

2226

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

2227

ret_errno = errno;

2228

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

2229

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

2230

errno = old_errno;

2231

return ret_errno;

2232

}

2233

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

2234

2235

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

2236

if(sd == -1){

2237

ret_errno = errno;

2238

perror_plus("socket");

2239

errno = old_errno;

2240

return ret_errno;

2241

}

2242

2243

if(debug){

2244

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

2245

interface);

2246

}

2247

2248

/* Raise privileges */

2249

ret_errno = raise_privileges();

2250

if(ret_errno != 0){

2251

errno = ret_errno;

2252

perror_plus("Failed to raise privileges");

2253

}

2254

2255

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

2256

ioctl_errno = errno;

2257

2258

/* If raise_privileges() succeeded above */

2259

if(ret_errno == 0){

2260

/* Lower privileges */

2261

ret_errno = lower_privileges();

2262

if(ret_errno != 0){

2263

errno = ret_errno;

2264

perror_plus("Failed to lower privileges");

2265

}

2266

}

2267

2268

/* Close the socket */

2269

int ret = close(sd);

2270

if(ret == -1){

2271

perror_plus("close");

2272

}

2273

2274

if(ret_setflags == -1){

2275

errno = ioctl_errno;

2276

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2277

errno = old_errno;

2278

return ioctl_errno;

2279

}

2280

} else if(debug){

2281

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

2282

interface);

2283

}

2284

2285

errno = old_errno;

2286

return 0;

1484

2287

}

1485

2288

1486

2289

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

2290

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

2291

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

2292

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2293

.current_server = NULL, .interfaces = NULL,

2294

.interfaces_size = 0 };

1487

2295

AvahiSServiceBrowser *sb = NULL;

1488

int error;

2296

error_t ret_errno;

1489

2297

int ret;

1490

2298

intmax_t tmpmax;

1491

2299

char *tmp;

1492

2300

int exitcode = EXIT_SUCCESS;

1493

const char *interface = "";

1494

struct ifreq network;

1495

int sd = -1;

1496

bool take_down_interface = false;

1497

uid_t uid;

1498

gid_t gid;

1499

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

1500

bool tempdir_created = false;

2301

char *interfaces_to_take_down = NULL;

2302

size_t interfaces_to_take_down_size = 0;

2303

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

2304

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

2305

char *tempdir = NULL;

1501

2306

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1502

2307

const char *seckey = PATHDIR "/" SECKEY;

1503

2308

const char *pubkey = PATHDIR "/" PUBKEY;

2309

const char *dh_params_file = NULL;

2310

char *interfaces_hooks = NULL;

1504

2311

1505

2312

bool gnutls_initialized = false;

1506

2313

bool gpgme_initialized = false;

1558

2365

.doc = "Bit length of the prime number used in the"

1559

2366

" Diffie-Hellman key exchange",

1560

2367

.group = 2 },

2368

{ .name = "dh-params", .key = 134,

2369

.arg = "FILE",

2370

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2371

" for the Diffie-Hellman key exchange",

2372

.group = 2 },

1561

2373

{ .name = "priority", .key = 130,

1562

2374

.arg = "STRING",

1563

2375

.doc = "GnuTLS priority string for the TLS handshake",

1568

2380

.group = 2 },

1569

2381

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

1570

2382

.arg = "SECONDS",

1571

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

2383

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

1572

2384

.group = 2 },

1573

2385

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

1574

2386

.arg = "DIR",

1597

2409

connect_to = arg;

1598

2410

break;

1599

2411

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

1600

interface = arg;

2412

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

2413

arg, (int)',');

2414

if(ret_errno != 0){

2415

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

2416

}

1601

2417

break;

1602

2418

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

1603

2419

seckey = arg;

1614

2430

}

1615

2431

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

1616

2432

break;

2433

case 134: /* --dh-params */

2434

dh_params_file = arg;

2435

break;

1617

2436

case 130: /* --priority */

1618

2437

mc.priority = arg;

1619

2438

break;

1646

2465

argp_state_help(state, state->out_stream,

1647

2466

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1648

2467

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

1651

2468

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

1652

2469

exit(argp_err_exit_status);

1653

2470

break;

1661

2478

.args_doc = "",

1662

2479

.doc = "Mandos client -- Get and decrypt"

1663

2480

" passwords from a Mandos server" };

1664

ret = argp_parse(&argp, argc, argv,

1665

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1666

switch(ret){

2481

ret_errno = argp_parse(&argp, argc, argv,

2482

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2483

switch(ret_errno){

1667

2484

case 0:

1668

2485

break;

1669

2486

case ENOMEM:

1670

2487

default:

1671

errno = ret;

2488

errno = ret_errno;

1672

2489

perror_plus("argp_parse");

1673

2490

exitcode = EX_OSERR;

1674

2491

goto end;

1677

2494

goto end;

1678

2495

}

1679

2496

}

1680

1681

if(getuid() == 0){

2497

2498

{

1682

2499

/* Work around Debian bug #633582:

1683

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

1684

struct stat st;

1685

1686

/* Re-raise priviliges */

1687

errno = 0;

1688

ret = seteuid(0);

1689

if(ret == -1){

1690

perror_plus("seteuid");

1691

}

1692

1693

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

1694

int seckey_fd = open(seckey, O_RDONLY);

1695

if(seckey_fd == -1){

1696

perror_plus("open");

1697

} else {

1698

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

1699

if(ret == -1){

1700

perror_plus("fstat");

1701

} else {

1702

if(S_ISREG(st.st_mode)

1703

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

1704

ret = fchown(seckey_fd, uid, gid);

1705

if(ret == -1){

1706

perror_plus("fchown");

1707

}

1708

}

1709

}

1710

TEMP_FAILURE_RETRY(close(seckey_fd));

1711

}

1712

}

1713

1714

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

1715

int pubkey_fd = open(pubkey, O_RDONLY);

1716

if(pubkey_fd == -1){

1717

perror_plus("open");

1718

} else {

1719

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

1720

if(ret == -1){

1721

perror_plus("fstat");

1722

} else {

1723

if(S_ISREG(st.st_mode)

1724

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

1725

ret = fchown(pubkey_fd, uid, gid);

1726

if(ret == -1){

1727

perror_plus("fchown");

1728

}

1729

}

1730

}

1731

TEMP_FAILURE_RETRY(close(pubkey_fd));

1732

}

1733

}

1734

1735

/* Lower privileges */

1736

errno = 0;

1737

ret = seteuid(uid);

1738

if(ret == -1){

1739

perror_plus("seteuid");

2500

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

2501

2502

/* Re-raise privileges */

2503

ret = raise_privileges();

2504

if(ret != 0){

2505

errno = ret;

2506

perror_plus("Failed to raise privileges");

2507

} else {

2508

struct stat st;

2509

2510

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

2511

int seckey_fd = open(seckey, O_RDONLY);

2512

if(seckey_fd == -1){

2513

perror_plus("open");

2514

} else {

2515

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

2516

if(ret == -1){

2517

perror_plus("fstat");

2518

} else {

2519

if(S_ISREG(st.st_mode)

2520

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

2521

ret = fchown(seckey_fd, uid, gid);

2522

if(ret == -1){

2523

perror_plus("fchown");

2524

}

2525

}

2526

}

2527

close(seckey_fd);

2528

}

2529

}

2530

2531

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

2532

int pubkey_fd = open(pubkey, O_RDONLY);

2533

if(pubkey_fd == -1){

2534

perror_plus("open");

2535

} else {

2536

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

2537

if(ret == -1){

2538

perror_plus("fstat");

2539

} else {

2540

if(S_ISREG(st.st_mode)

2541

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

2542

ret = fchown(pubkey_fd, uid, gid);

2543

if(ret == -1){

2544

perror_plus("fchown");

2545

}

2546

}

2547

}

2548

close(pubkey_fd);

2549

}

2550

}

2551

2552

if(dh_params_file != NULL

2553

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2554

int dhparams_fd = open(dh_params_file, O_RDONLY);

2555

if(dhparams_fd == -1){

2556

perror_plus("open");

2557

} else {

2558

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

2559

if(ret == -1){

2560

perror_plus("fstat");

2561

} else {

2562

if(S_ISREG(st.st_mode)

2563

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

2564

ret = fchown(dhparams_fd, uid, gid);

2565

if(ret == -1){

2566

perror_plus("fchown");

2567

}

2568

}

2569

}

2570

close(dhparams_fd);

2571

}

2572

}

2573

2574

/* Lower privileges */

2575

ret = lower_privileges();

2576

if(ret != 0){

2577

errno = ret;

2578

perror_plus("Failed to lower privileges");

2579

}

2580

}

2581

}

2582

2583

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

2584

{

2585

char *interface = NULL;

2586

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

2587

interface))){

2588

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

2589

and if_nametoindex(interface) == 0){

2590

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

2591

fprintf_plus(stderr, "Not using nonexisting interface"

2592

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

2593

}

2594

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

2595

interface = NULL;

2596

}

1740

2597

}

1741

2598

}

1742

2599

1743

2600

/* Run network hooks */

1744

2601

{

1745

if(getuid() == 0){

1746

/* Re-raise priviliges */

1747

errno = 0;

1748

ret = seteuid(0);

1749

if(ret == -1){

1750

perror_plus("seteuid");

1751

}

1752

}

1753

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

1754

goto end;

1755

}

1756

if(getuid() == 0){

1757

/* Lower privileges */

1758

errno = 0;

1759

ret = seteuid(uid);

1760

if(ret == -1){

1761

perror_plus("seteuid");

1762

}

1763

}

2602

if(mc.interfaces != NULL){

2603

interfaces_hooks = malloc(mc.interfaces_size);

2604

if(interfaces_hooks == NULL){

2605

perror_plus("malloc");

2606

goto end;

2607

}

2608

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

2609

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

2610

}

2611

run_network_hooks("start", interfaces_hooks != NULL ?

2612

interfaces_hooks : "", delay);

1764

2613

}

1765

2614

1766

2615

if(not debug){

1767

2616

avahi_set_log_function(empty_log);

1768

2617

}

1769

2618

1770

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

1771

struct dirent **direntries;

1772

/* First look for interfaces that are up */

1773

ret = scandir(sys_class_net, &direntries, up_interface,

1774

alphasort);

1775

if(ret == 0){

1776

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

1777

free(direntries);

1778

ret = scandir(sys_class_net, &direntries, good_interface,

1779

alphasort);

1780

}

1781

if(ret >= 1){

1782

/* Pick the first interface returned */

1783

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

1784

if(debug){

1785

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

1786

}

1787

if(interface == NULL){

1788

perror_plus("malloc");

1789

free(direntries);

1790

exitcode = EXIT_FAILURE;

1791

goto end;

1792

}

1793

free(direntries);

1794

} else {

1795

free(direntries);

1796

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

1797

exitcode = EXIT_FAILURE;

1798

goto end;

1799

}

1800

}

1801

1802

2619

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

1803

2620

from the signal handler */

1804

2621

/* Initialize the pseudo-RNG for Avahi */

1805

2622

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

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2623

simple_poll = avahi_simple_poll_new();

2624

if(simple_poll == NULL){

1808

2625

fprintf_plus(stderr,

1809

2626

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

1810

2627

exitcode = EX_UNAVAILABLE;

1874

2691

}

1875

2692

}

1876

2693

1877

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

1878

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

1879

if_index = (AvahiIfIndex) if_nametoindex(interface);

1880

if(if_index == 0){

1881

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

1882

exitcode = EX_UNAVAILABLE;

1883

goto end;

1884

}

1885

1886

if(quit_now){

1887

goto end;

1888

}

1889

1890

/* Re-raise priviliges */

1891

errno = 0;

1892

ret = seteuid(0);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

1897

#ifdef __linux__

1898

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1899

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

1900

ret = klogctl(8, NULL, 5);

1901

bool restore_loglevel = true;

1902

if(ret == -1){

1903

restore_loglevel = false;

1904

perror_plus("klogctl");

1905

}

1906

#endif /* __linux__ */

1907

1908

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1909

if(sd < 0){

1910

perror_plus("socket");

1911

exitcode = EX_OSERR;

1912

#ifdef __linux__

1913

if(restore_loglevel){

1914

ret = klogctl(7, NULL, 0);

1915

if(ret == -1){

1916

perror_plus("klogctl");

1917

}

1918

}

1919

#endif /* __linux__ */

1920

/* Lower privileges */

1921

errno = 0;

1922

ret = seteuid(uid);

1923

if(ret == -1){

1924

perror_plus("seteuid");

1925

}

1926

goto end;

1927

}

1928

strcpy(network.ifr_name, interface);

1929

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

1930

if(ret == -1){

1931

perror_plus("ioctl SIOCGIFFLAGS");

1932

#ifdef __linux__

1933

if(restore_loglevel){

1934

ret = klogctl(7, NULL, 0);

1935

if(ret == -1){

1936

perror_plus("klogctl");

1937

}

1938

}

1939

#endif /* __linux__ */

1940

exitcode = EX_OSERR;

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

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

1950

network.ifr_flags |= IFF_UP;

1951

take_down_interface = true;

1952

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

1953

if(ret == -1){

1954

take_down_interface = false;

1955

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1956

exitcode = EX_OSERR;

1957

#ifdef __linux__

1958

if(restore_loglevel){

1959

ret = klogctl(7, NULL, 0);

1960

if(ret == -1){

1961

perror_plus("klogctl");

2694

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

2695

if(mc.interfaces == NULL){

2696

struct dirent **direntries = NULL;

2697

/* Look for any good interfaces */

2698

ret = scandir(sys_class_net, &direntries, good_interface,

2699

alphasort);

2700

if(ret >= 1){

2701

/* Add all found interfaces to interfaces list */

2702

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

2703

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

2704

direntries[i]->d_name);

2705

if(ret_errno != 0){

2706

errno = ret_errno;

2707

perror_plus("argz_add");

2708

free(direntries[i]);

2709

continue;

2710

}

2711

if(debug){

2712

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

2713

direntries[i]->d_name);

2714

}

2715

free(direntries[i]);

2716

}

2717

free(direntries);

2718

} else {

2719

if(ret == 0){

2720

free(direntries);

2721

}

2722

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

2723

exitcode = EXIT_FAILURE;

2724

goto end;

2725

}

2726

}

2727

2728

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

2729

{

2730

char *interface = NULL;

2731

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

2732

interface))){

2733

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

2734

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

2735

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

2736

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

2737

interface);

2738

interface = NULL;

2739

while((interface = argz_next(mc.interfaces,

2740

mc.interfaces_size, interface))){

2741

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

2742

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

2743

interface);

2744

interface = NULL;

1962

2745

}

1963

2746

}

1964

#endif /* __linux__ */

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

}

1974

/* Sleep checking until interface is running.

1975

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

1976

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

1977

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

1978

if(ret == -1){

1979

perror_plus("ioctl SIOCGIFFLAGS");

1980

} else if(network.ifr_flags & IFF_RUNNING){

1981

2747

break;

1982

2748

}

1983

struct timespec sleeptime = { .tv_nsec = 250000000 };

1984

ret = nanosleep(&sleeptime, NULL);

1985

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

1986

perror_plus("nanosleep");

1987

}

1988

}

1989

if(not take_down_interface){

1990

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

1991

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

1992

if(ret == -1){

1993

perror_plus("close");

1994

}

1995

}

1996

#ifdef __linux__

1997

if(restore_loglevel){

1998

/* Restores kernel loglevel to default */

1999

ret = klogctl(7, NULL, 0);

2000

if(ret == -1){

2001

perror_plus("klogctl");

2002

}

2003

}

2004

#endif /* __linux__ */

2005

/* Lower privileges */

2006

errno = 0;

2007

/* Lower privileges */

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2011

}

2749

bool interface_was_up = interface_is_up(interface);

2750

errno = bring_up_interface(interface, delay);

2751

if(not interface_was_up){

2752

if(errno != 0){

2753

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2754

" %s\n", interface, strerror(errno));

2755

} else {

2756

errno = argz_add(&interfaces_to_take_down,

2757

&interfaces_to_take_down_size,

2758

interface);

2759

if(errno != 0){

2760

perror_plus("argz_add");

2761

}

2762

}

2763

}

2764

}

2765

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

2766

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

2767

}

2768

}

2769

2770

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

2771

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

2772

if(debug){

2773

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

2774

mc.interfaces);

2775

}

2776

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

2012

2777

}

2013

2778

2014

2779

if(quit_now){

2015

2780

goto end;

2016

2781

}

2017

2782

2018

ret = init_gnutls_global(pubkey, seckey);

2783

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

2019

2784

if(ret == -1){

2020

2785

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

2021

2786

exitcode = EX_UNAVAILABLE;

2028

2793

goto end;

2029

2794

}

2030

2795

2031

if(mkdtemp(tempdir) == NULL){

2796

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

2797

tempdir = mkdtemp(run_tempdir);

2798

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

2799

if(debug){

2800

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

2801

run_tempdir, old_tempdir);

2802

}

2803

tempdir = mkdtemp(old_tempdir);

2804

}

2805

if(tempdir == NULL){

2032

2806

perror_plus("mkdtemp");

2033

2807

goto end;

2034

2808

}

2035

tempdir_created = true;

2036

2809

2037

2810

if(quit_now){

2038

2811

goto end;

2039

2812

}

2040

2813

2041

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

2814

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

2042

2815

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

2043

2816

exitcode = EX_UNAVAILABLE;

2044

2817

goto end;

2054

2827

/* Connect directly, do not use Zeroconf */

2055

2828

/* (Mainly meant for debugging) */

2056

2829

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

2830

2057

2831

if(address == NULL){

2058

2832

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

2059

2833

exitcode = EX_USAGE;

2064

2838

goto end;

2065

2839

}

2066

2840

2067

uint16_t port;

2841

in_port_t port;

2068

2842

errno = 0;

2069

2843

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

2070

2844

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

2071

or tmpmax != (uint16_t)tmpmax){

2845

or tmpmax != (in_port_t)tmpmax){

2072

2846

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

2073

2847

exitcode = EX_USAGE;

2074

2848

goto end;

2075

2849

}

2076

2850

2077

2851

if(quit_now){

2078

2852

goto end;

2079

2853

}

2080

2854

2081

port = (uint16_t)tmpmax;

2855

port = (in_port_t)tmpmax;

2082

2856

*address = '\0';

2083

2857

/* Colon in address indicates IPv6 */

2084

2858

int af;

2100

2874

}

2101

2875

2102

2876

while(not quit_now){

2103

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

2877

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

2878

&mc);

2104

2879

if(quit_now or ret == 0){

2105

2880

break;

2106

2881

}

2108

2883

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

2109

2884

(int)retry_interval);

2110

2885

}

2111

sleep((int)retry_interval);

2886

sleep((unsigned int)retry_interval);

2112

2887

}

2113

2888

2114

if (not quit_now){

2889

if(not quit_now){

2115

2890

exitcode = EXIT_SUCCESS;

2116

2891

}

2117

2892

2132

2907

config.publish_domain = 0;

2133

2908

2134

2909

/* Allocate a new server */

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2910

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2911

&config, NULL, NULL, &ret);

2138

2912

2139

2913

/* Free the Avahi configuration data */

2140

2914

avahi_server_config_free(&config);

2143

2917

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

2144

2918

if(mc.server == NULL){

2145

2919

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

2146

avahi_strerror(error));

2920

avahi_strerror(ret));

2147

2921

exitcode = EX_UNAVAILABLE;

2148

2922

goto end;

2149

2923

}

2155

2929

/* Create the Avahi service browser */

2156

2930

sb = avahi_s_service_browser_new(mc.server, if_index,

2157

2931

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2158

NULL, 0, browse_callback, NULL);

2932

NULL, 0, browse_callback,

2933

(void *)&mc);

2159

2934

if(sb == NULL){

2160

2935

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

2161

2936

avahi_strerror(avahi_server_errno(mc.server)));

2172

2947

if(debug){

2173

2948

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

2174

2949

}

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2950

2951

ret = avahi_loop_with_timeout(simple_poll,

2952

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

2178

2953

if(debug){

2179

2954

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

2180

2955

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

2183

2958

end:

2184

2959

2185

2960

if(debug){

2186

fprintf_plus(stderr, "%s exiting\n", argv[0]);

2961

if(signal_received){

2962

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

2963

argv[0], signal_received,

2964

strsignal(signal_received));

2965

} else {

2966

fprintf_plus(stderr, "%s exiting\n", argv[0]);

2967

}

2187

2968

}

2188

2969

2189

2970

/* Cleanup things */

2971

free(mc.interfaces);

2972

2190

2973

if(sb != NULL)

2191

2974

avahi_s_service_browser_free(sb);

2192

2975

2193

2976

if(mc.server != NULL)

2194

2977

avahi_server_free(mc.server);

2195

2978

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

2979

if(simple_poll != NULL)

2980

avahi_simple_poll_free(simple_poll);

2198

2981

2199

2982

if(gnutls_initialized){

2200

2983

gnutls_certificate_free_credentials(mc.cred);

2201

gnutls_global_deinit();

2202

2984

gnutls_dh_params_deinit(mc.dh_params);

2203

2985

}

2204

2986

2212

2994

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

2213

2995

while(mc.current_server != NULL){

2214

2996

server *next = mc.current_server->next;

2997

#ifdef __GNUC__

2998

#pragma GCC diagnostic push

2999

#pragma GCC diagnostic ignored "-Wcast-qual"

3000

#endif

3001

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

3002

#ifdef __GNUC__

3003

#pragma GCC diagnostic pop

3004

#endif

2215

3005

free(mc.current_server);

2216

3006

mc.current_server = next;

2217

3007

}

2218

3008

}

2219

3009

2220

/* Re-raise priviliges */

3010

/* Re-raise privileges */

2221

3011

{

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

3012

ret = raise_privileges();

3013

if(ret != 0){

3014

errno = ret;

3015

perror_plus("Failed to raise privileges");

3016

} else {

3017

3018

/* Run network hooks */

3019

run_network_hooks("stop", interfaces_hooks != NULL ?

3020

interfaces_hooks : "", delay);

3021

3022

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

3023

{

3024

char *interface = NULL;

3025

while((interface=argz_next(interfaces_to_take_down,

3026

interfaces_to_take_down_size,

3027

interface))){

3028

ret = take_down_interface(interface);

3029

if(ret != 0){

3030

errno = ret;

3031

perror_plus("Failed to take down interface");

3032

}

3033

}

3034

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

3035

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

3036

" down\n");

3037

}

2227

3038

}

2228

3039

}

2229

3040

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Take down the network interface */

2234

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

2235

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

2236

if(ret == -1){

2237

perror_plus("ioctl SIOCGIFFLAGS");

2238

} else if(network.ifr_flags & IFF_UP){

2239

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

2240

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

2241

if(ret == -1){

2242

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2243

}

2244

}

2245

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

2246

if(ret == -1){

2247

perror_plus("close");

2248

}

3041

ret = lower_privileges_permanently();

3042

if(ret != 0){

3043

errno = ret;

3044

perror_plus("Failed to lower privileges permanently");

2249

3045

}

2250

3046

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

3047

3048

free(interfaces_to_take_down);

3049

free(interfaces_hooks);

3050

3051

void clean_dir_at(int base, const char * const dirname,

3052

uintmax_t level){

3053

struct dirent **direntries = NULL;

3054

int dret;

3055

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3056

O_RDONLY

3057

| O_NOFOLLOW

3058

| O_DIRECTORY

3059

| O_PATH));

3060

if(dir_fd == -1){

3061

perror_plus("open");

3062

}

3063

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

3064

notdotentries, alphasort);

3065

if(numentries >= 0){

3066

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

3067

if(debug){

3068

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3069

dirname, direntries[i]->d_name);

3070

}

3071

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3072

if(dret == -1){

3073

if(errno == EISDIR){

3074

dret = unlinkat(dir_fd, direntries[i]->d_name,

3075

AT_REMOVEDIR);

3076

}

3077

if((dret == -1) and (errno == ENOTEMPTY)

3078

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3079

== 0) and (level == 0)){

3080

/* Recurse only in this special case */

3081

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3082

dret = 0;

3083

}

3084

if(dret == -1){

3085

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3086

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

3087

}

3088

}

3089

free(direntries[i]);

3090

}

3091

3092

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

3093

free(direntries);

3094

if(numentries == -1){

3095

perror_plus("scandirat");

3096

}

3097

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3098

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

3099

perror_plus("rmdir");

3100

}

3101

} else {

3102

perror_plus("scandirat");

3103

}

3104

close(dir_fd);

2258

3105

}

2259

3106

2260

3107

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

2261

if(tempdir_created){

2262

struct dirent **direntries = NULL;

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

2267

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

2268

direntry = direntries[i];

2269

char *fullname = NULL;

2270

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

2271

direntry->d_name);

2272

if(ret < 0){

2273

perror_plus("asprintf");

2274

continue;

2275

}

2276

ret = remove(fullname);

2277

if(ret == -1){

2278

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

2279

strerror(errno));

2280

}

2281

free(fullname);

2282

}

2283

}

2284

2285

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

2286

free(direntries);

2287

if (numentries == -1){

2288

perror_plus("scandir");

2289

}

2290

ret = rmdir(tempdir);

2291

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

2292

perror_plus("rmdir");

2293

}

3108

if(tempdir != NULL){

3109

clean_dir_at(-1, tempdir, 0);

2294

3110

}

2295

3111

2296

3112

if(quit_now){